[Elenco soci]


Governi Lapo

Professore Ordinario


Università degli Studi di Firenze
lapo.governi@unifi.it

Sito istituzionale
SCOPUS ID: 6508036265
Orcid: 0000-0002-7417-3487



Pubblicazioni scientifiche

[1] Di Angelo L., Di Stefano P., Governi L., Marzola A., Volpe Y., Can MaWR-Method for Symmetry Plane Detection be Generalized for Complex Panfacial Fractures?, Lecture Notes in Mechanical Engineering, 148-158, (2023). Abstract
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Abstract: When dealing with craniofacial impairments, restoring the morphological condition is as crucial as restoring the functional ones to avoid psychosocial disabilities for the patient. For this aim, the accurate location of the midsagittal plane is essential for performing reliable symmetry analyses and guiding effective surgery planning. To provide a fully automatic and landmark-independent approach, capable of providing a midsagittal plane for craniofacial skeleton even from anatomical models with high asymmetries, an innovative method, called MaWR-method, was developed by the authors in a previous work. This paper further investigates the MaWR-method by evaluating its capacity to produce a successful outcome even in the worst-case scenario that may be considered in maxillofacial surgery, namely panfacial fractures. In all the test cases considered in this work, the method proved robust and reliable in its original design. It provided a consistent result requiring no user involvement, even when dealing with extreme asymmetries because of extensive and complex fractures.

Keywords: Feature recognition | Mid-sagittal plane | Symmetry analysis | Symmetry plane detection

[2] Puggelli L., Carfagni M., Furferi R., Governi L., Optimizing Galvanic Process: Wet Surface Estimation for Small Metal Parts to Avoid Material Waste, Lecture Notes in Mechanical Engineering, 743-754, (2023). Abstract
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Abstract: The optimization of a galvanic process is a crucial task for many manufacturers in the field of electro-deposition industry. This is true for companies operating in the high fashion field, in which expensive materials are used and reducing material waste is crucial. In this paper, the estimation of the wet surface of small metal parts is treated. In fact, considering a single piece, the amount of material required to guarantee a desired plate thickness is directly proportional to its outer surface. Starting with a rapid overview on other methods to come up with this task, the attention in principally oriented to surface estimation by means of optical scanning. A preliminary test session has been carried out and two main issues arose. The first one is related to resolution and accuracy: due to pieces small dimensions and details, high performances are required to achieve valid results. The second and principal issue is related to the high reflectivity of pieces, even before electroplating. With the aim of avoiding the use of matting paint (which is difficult to remove), the attention has been focused on commercial solution dedicated to jewellery and dentistry fields. Three devices (based on white and blue LED structured light) have been tested on high reflective and specular pieces. From the analyses, only the one based on blue LED technology was able to retrieve high reflective surfaces without matting. Minor issues arose in case of specular surface. The device has been considered suitable for the task.

Keywords: 3D optical scanners | 3D reconstruction | Blue LED structured light | Galvanic | Reverse engineering

[3] Dalle Mura F., Governi L., Furferi R., Cervo M., Puggelli L., Towards the Development of a Device for Assessing the Pliability of Burn Scars, Frontiers in Bioengineering and Biotechnology, 10, (2022). Abstract
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Abstract: Burn injuries requires post-accident medical treatment. However, the treatment of burns does not end with first aid because scarred skin must be managed for many years, and in some circumstances, for life. The methods used to evaluate the state of a burn scar based, for instance, on Patient and Observer Scar Assessment Scale or similar ones, often lacks in univocally assessing the scarred skin’s state of health. As a result, the primary aim of this research is to design and build a prototype that can support the doctor during scar assessment, and eventually therapy, by providing objective information on the state of the lesion, particularly the value of skin pliability. The developed tool is based on the depressomassage treatment probe named LPG, currently used to treat burn scars in a number of hospitals. It consists of a non-invasive massage technique using a mechanical device to suction and mobilize scar tissue and is used as a post-operative treatment to speed up the healing process to make the mark of the scar less visible. The prototype is specifically designed to be manufactured using Additive Manufacturing and was validated comparing its performances against the ones of a certified instrument (i.e., the Romer Absolute ARM with RS1 probe). Validation was carried out by designing and developing a tool to put the RS1 probe in the same measurement conditions of the new prototype probe. Tests performed to assess the performance of the devised prototype show that the probe developed in this work is able to provide measurements with a sufficient degree of accuracy (maximum error ±0.1 mm) to be adopted for a reliable estimation of the pliability value in a hospital environment.

Keywords: 3D measurement | additive manufacturing (3D printing) | burn scars | pliability | reverse engineering

[4] Marzola A., Buonamici F., Guariento L., Governi L., Enhanced Statistical Shape Model: A Statistical-Based Tool to design Custom Orthopaedic Devices, Lecture Notes in Mechanical Engineering, 27-38, (2022). Abstract
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Abstract: Dealing with the design of personalized medical devices, mass production is not an option that can be hypothesized. Indeed, a cumbersome production process must be considered in such cases, mainly to account for a delicate design phase that needs to take into consideration, as input, an anatomy that vary each time. This article discusses the development of a statistical tool able to support the design of patient-specific devices. By expanding the classical formulation of the Statistical Shape Model (SSM) with the introduction of multiple levels of information within the same model, the authors have experimented with the concept of an “enhanced SSM”. While the traditional SSM only provides information on the variations that a class of shapes can manifest, the eSSM may include more levels of information. The article discusses two possible mathematical formulations of such statistical tool. Its application to the design of custom-made pelvic implants is discussed. Such application scenario is described starting from the generation of the eSSM for the pelvis. The features of interest considered in this paper are the centers of the acetabular regions of the pelvis, the segmentation of the anatomy in a series of semantical regions that must be considered when developing a load-bearing implant. Finally, the conclusions of this research are drawn and discussed together with possible future development of eSSMs.

Keywords: Biomedical engineering | Custom implant design | Human modelling | Pelvis | SSM | Statistical shape analysis

[5] Santarelli C., Puggelli L., Carfagni M., Governi L., Preliminary Study of a High-Fidelity Simulator for the Management of Paediatric Tracheal Pathologies, Lecture Notes in Mechanical Engineering, 773-784, (2022). Abstract
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Abstract: In the biomedical field, high-fidelity simulation plays a fundamental role for medical and surgical staff as it allows them to simulate real scenarios from everyday clinical practice. The availability of patient-specific pathological models allows doctors to simulate surgical procedures before entering the operating room, thus reducing the risks associated with surgery. Such models are also employed in medical training to enhance the experience of trainees by confronting them with possible real-life emergency scenarios. To obtain a strict correspondence between simulator and reality - both in terms of geometry and haptic feedback - important decisions must be taken from the beginning of the design phase. High fidelity is a fundamental requirement of the simulators, since the design phase of the anatomical model, for what concerns geometries and materials. In this paper, a preliminary study for the development of a paediatric tracheal simulator is presented. This study is focused on the definition of some general geometric parameters and of the material composing the simulator. Mechanical characteristics of the trachea are investigated to identify a set of materials able to reproduce a realistic haptic feedback of the simulator. Materials are chosen in relation with the technological process that will be used for the simulator manufacturing: additive manufacturing or mould casting. To test the various materials, specimens are created and submitted to the judgement of a specialized medical team. The results showed Shore 40A silicone with a 1.75 mm wall-thickness value to be the best compromise for reproducing the haptic feedback of the trachea.

Keywords: 3D printing | Airway simulation | Haptic feedback | Paediatric trachea | Soft tissue modelling

[6] Uccheddu F., Furferi R., Governi L., Carfagni M., Rgb-d-based method for measuring the angular range of hip and knee joints during home care rehabilitation, Sensors, 22(1), (2022). Abstract
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Abstract: Home-based rehabilitation is becoming a gold standard for patient who have undergone knee arthroplasty or full knee replacement, as it helps healthcare costs to be minimized. Nevertheless, there is a chance of increasing adverse health effects in case of home care, primarily due to the patients’ lack of motivation and the doctors’ difficulty in carrying out rigorous supervision. The development of devices to assess the efficient recovery of the operated joint is highly valued both for the patient, who feels encouraged to perform the proper number of activities, and for the doctor, who can track him/her remotely. Accordingly, this paper introduces an interactive approach to angular range calculation of hip and knee joints based on the use of low-cost devices which can be operated at home. First, the patient’s body posture is estimated using a 2D acquisition method. Subsequently, the 3D posture is evaluated by using the depth information coming from an RGB-D sensor. Preliminary results show that the proposed method effectively overcomes many limitations by fusing the results obtained by the state-of-the-art robust 2D pose estimation algorithms with the 3D data of depth cameras by allowing the patient to be correctly tracked during rehabilitation exercises.

Keywords: 3D model | Body tracking | Data fusion | Joints estimation | RGB-D camera

[7] Furferi R., Governi L., Pinzauti E., Profili A., Puggelli L., Volpe Y., A computational method for the investigation of burn scars topology based on 3D optical scan, Computers in Biology and Medicine, 149, (2022). Abstract
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Abstract: Burn scar treatment is a difficult subject to address since the improper therapy can have a significant impact on people's quality of life. The evaluation of medical therapy over time should be based on objective measurement of the severity of burn scars and their progression. Unfortunately, most clinical assessments of scars are still reliant on physicians' subjective exams of patients. A profitable method to overcome the limitations of subjective assessment could be to leverage 3D scanning technologies. These could be used to retrieve the surface topology of burns. Accordingly, the goal of this study is to provide an objective approach for analysing the surface topology of burn scars using 3D scanning and roughness-based evaluation. In particular, two types of ISO-compliant profile and surface filters (Gaussian and Wavelet) derived from the analysis of roughness in the mechanical sector are implemented to discriminate form from roughness of scars. Once retrieved, the roughness surface is processed to derive a set of statistical parameters describing the scar surface topology. Three case studies were used to derive these parameters (a synthetic surface, an ostrich-skin surface and a set of scars). After the surface's roughness was determined, a comparison between healthy and unhealthy skin could be established. The devised methods prove their effectiveness in correctly retrieving the main surface characteristics of a burn scar. Therefore, by using the proposed method it will be possible to evaluate the effectiveness of medical therapy by comparing the healthy and scarred skin of a single subject.

Keywords: 3D scanning | Burn scars | Gaussian filtering | Roughness | Wavelet filtering

[8] Servi M., Mussi E., Profili A., Furferi R., Volpe Y., Governi L., Buonamici F., Metrological characterization and comparison of D415, D455, L515 realsense devices in the close range, Sensors, 21(22), (2021). Abstract
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Abstract: RGB-D cameras are employed in several research fields and application scenarios. Choosing the most appropriate sensor has been made more difficult by the increasing offer of available products. Due to the novelty of RGB-D technologies, there was a lack of tools to measure and compare performances of this type of sensor from a metrological perspective. The recent ISO 10360-13:2021 represents the most advanced international standard regulating metrological characterization of coordinate measuring systems. Part 13, specifically, considers 3D optical sensors. This paper applies the methodology of ISO 10360-13 for the characterization and comparison of three RGB-D cameras produced by Intel® RealSense™ (D415, D455, L515) in the close range (100–1500 mm). ISO 10360-13 procedures, which focus on metrological performances, are integrated with additional tests to evaluate systematic errors (acquisition of flat objects, 3D reconstruction of objects). The present paper proposes an off-the-shelf comparison which considers the performance of the sensors throughout their acquisition volume. Results have exposed the strengths and weaknesses of each device. The D415 device showed better reconstruction quality on tests strictly related to the short range. The L515 device performed better on systematic depth errors; finally, the D455 device achieved better results on tests related to the standard.

Keywords: Active stereo | Depth camera | Device characterization | ISO 10360-13 | LiDAR | Performance comparison | RealSense D415 | RealSense D455 | RealSense L515 | Reverse engineering

[9] Buonamici F., Carfagni M., Furferi R., Volpe Y., Governi L., Reverse engineering by CAD template fitting: study of a fast and robust template-fitting strategy, Engineering with Computers, 37(4), 2803-2821, (2021). Abstract
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Abstract: This paper considers the fitting of a CAD template model to tessellated data as strategy to implement a reverse engineering process that aims at the reconstruction of a parametric associative CAD model. The reconstruction methodology, called Template-Based CAD Reconstruction (TCRT), has been presented and fully discussed in a previous paper Buonamici et al. (J Comput Des Eng 5:145–159, 2018). The present paper focuses on the study of a fast and robust strategy to perform the fitting of the Template CAD Model to reference data. The study explores how different optimization strategies and evaluation metrics can affect a parametric CAD-fitting methodology. Two different optimization algorithms (PSO and GA) and three formulations of the objective function are tested to find the most effective combination. Reconstruction test cases are presented and discussed in the text.

Keywords: CAD reconstruction | CAD template | Fitting | Genetic Algorithm | Particle Swarm Optimization | Reverse engineering

[10] Marzola A., Buonamici F., Furferi R., Governi L., Genitori L., Mussa F., Additive manufacturing and reverse engineering in cranioplasty: A personalized approach to minimize skin flap complications, Applied Sciences (Switzerland), 11(11), (2021). Abstract
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Abstract: Cranioplasty is a procedure performed to repair defects in the human skull bone by surgically reconstructing the shape and function of the cranium. Several complications, both intraoperative and postoperative, can affect the procedure’s outcome (e.g., inaccuracies of the reconstructed shape, infections, ulcer, necrosis). Although the design of additive manufactured implants in a preoperative stage has improved the general quality of cranioplasties, potential complications remain significant, especially in the presence of critical skin tissue conditions. In this paper, an innovative procedure to improve the chances of a positive outcome when facing critical conditions in a cranioplasty is described. The proposed approach relies on a structured planning phase articulated in a series of digital analyses and physical simulations performed on personalized medical devices that guide the surgeon in defining surgical cuts and designing the implant. The ultimate goal is to improve the chances of a positive outcome and a fast recovery for the patient. The procedure, described in extenso in the paper, was positively tested on a cranioplasty case study, which presented high risk factors.

Keywords: Additive manufacturing | Cranioplasty | Patient-specific implant | Skull reconstruction

[11] Uccheddu F., Governi L., Furferi R., Carfagni M., Home physiotherapy rehabilitation based on RGB-D sensors: a hybrid approach to the joints angular range of motion estimation, International Journal on Interactive Design and Manufacturing, 15(1), 99-102, (2021). Abstract
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Abstract: Home-based recovery is gradually being used to reduce health-care costs; however, with a shorter stay in the hospital, the risk of growing adverse clinical outcomes exists, mainly due to the lack of motivation in the patient and on the difficulties in performing a strict control by the doctors. This is particularly true for patients who went under knee arthroplasty or total knee replacement who should strictly follow the effective recovery protocols delivered by the doctors. The development of tools for measuring the functional recovery of the operated joint is therefore deemed crucial both for the patient to feel motivated in performing the right number of exercises, and for the doctor that can follow him/her up remotely. One of the most recognized methods for assessing the correctness of a series of recovery exercises, is to monitor the pose of the patient in real-time so as to evaluate its posture in his range of motion. Accordingly, in this paper a novel hybrid approach to 3D human pose estimation is proposed. A first estimation of 2D body pose of the patient in the scene is given, then the depth information coming from the RGB-D sensor is exploited to estimate the joints 3D coordinates. The proposed algorithm proved to overcome the main limitation of using a pure 3D skeleton tracking algorithm during physiotherapy rehabilitation.

Keywords: 3D | Body tracking | Data fusion | Joints estimation | RGB-D camera

[12] Marzola A., Robilotta C., Volpe Y., Governi L., Furferi R., Statistical Shape Model: comparison between ICP and CPD algorithms on medical applications, International Journal on Interactive Design and Manufacturing, 15(1), 85-89, (2021). Abstract
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Abstract: The increasing availability of 3D anatomical models obtained from diagnostic images exploiting Reverse Engineering techniques allows the application of statistical analysis in the quantitative investigation of anatomical shapes variability. Statistical Shape Models are a well-established method for representing such variability, especially for complex forms like the anatomical ones. Not by chance, these models are widely used for medical applications, such as guiding segmentation of the diagnostic image and virtual reconstruction of incomplete anatomic region. The application of a statistical analysis on a set of shapes representing the same anatomical region essentially requires that shapes must be in correspondence, i.e. constituted by the same number of points in corresponding position. This work aims to compare two established algorithms, namely a modified version of the Iterative Closest Point and the non-rigid version of the Coherent Point Drift, to solve the correspondences’ problem in the construction of a Statistical Shape Model of the human cranium. The comparison is carried out on the models using the standard evaluation criteria: Generalization, Specificity and Compactness. The modified version of the Iterative Closest Point delivers a better Statistical Shape Model in terms of Generalization and Specificity, but not for Compactness, than the Coherent Point Drift-based model.

Keywords: Computer-Aided Technologies | Correspondences’ problem | Reverse Engineering | Statistical Shape Analysis | Statistical Shape Model

[13] Mussi E., Servi M., Facchini F., Furferi R., Governi L., Volpe Y., A novel ear elements segmentation algorithm on depth map images, Computers in Biology and Medicine, 129, (2021). Abstract
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Abstract: The growing interest in the auricular anatomy is due to two different strands of research: 1) in the medical field it is associated with autologous ear reconstruction, a surgery adopted following trauma or congenital malformations; 2) in surveillance and law enforcement the ear is used for human detection and recognition. Alternative systems of ear analysis can be differentiated for the type of input data (two-dimensional, three-dimensional or both), for the type of acquisition tools (3D scanner, photographs, video surveillance, etc.) and finally for the adopted algorithms. Although the segmentation and recognition of the ear from the face is a widely discussed topic in literature, the detection and recognition of individual anatomical elements has not yet been studied in depth. To this end, this work lays the foundation for the identification of the auricular elements through image processing algorithms. The proposed algorithm automatically identifies the contours of the main anatomical elements by processing depth map images. The algorithm was tested qualitatively and quantitatively on a dataset composed of 150 ears. The qualitative evaluation was performed with the collaboration of medical staff and the quantitative tests were performed using manually annotated ground truth data.

Keywords: Depth map | Ear biometrics | Ear dataset | Ear reconstruction | Ear segmentation | Microtia

[14] Mussi E., Servi M., Furferi R., Governi L., Facchini F., Volpe Y., G-ear: A user-friendly tool for assisted autologous ear reconstruction, Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS, 2750-2755, (2021). Abstract
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Abstract: The major breakthroughs in the fields of reverse engineering and additive manufacturing have dramatically changed medical practice in recent years, pushing for a modern clinical model in which each patient is considered unique. Among the wide spectrum of medical applications, reconstructive surgery is experiencing the most benefits from this new paradigm. In this scenario, the present paper focuses on the design and development of a tool able to support the surgeon in the reconstruction of the external ear in case of malformation or total absence of the anatomy. In particular, the paper describes an appositely devised software tool, named G-ear, which enables the semi-automatic modeling of intraoperative devices to guide the physician through ear reconstruction surgery. The devised system includes 3D image segmentation, semi-automated CAD modelling and 3D printing to manufacture a set of patient-specific surgical guides for ear reconstruction. Usability tests were carried out among the surgeons of the Meyer Children's Hospital to obtain an assessment of the software by the end user. The devised system proved to be fast and efficient in retrieving the optimal 3D geometry of the surgical guides and, at the same time, to be easy to use and intuitive, thus achieving high degrees of likability.

[15] Carfagni M., Fiorineschi L., Furferi R., Governi L., Rotini F., Usefulness of prototypes in conceptual design: students’ view, International Journal on Interactive Design and Manufacturing, 14(4), 1305-1319, (2020). Abstract
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Abstract: Planning prototyping strategies for conceptual design purposes is a crucial activity, which needs a clear understanding of the potentialities of the different typologies of prototype. Therefore, to prepare future designers, it is very important to provide the required information in design-related academic courses. However, prototypes and prototyping activities are often taught in specific courses with a major emphasis on the underpinning technologies, but with limited attention on design implications, especially about the fuzzy-front-end of the design process. The work presented in this paper aims at investigating about how students perceive the usefulness of prototypes during conceptual design activities, in order to provide first indications about the gap to be filled. To this purpose, two classes of students participated to an experimental session, and were asked to perform a conceptual design task individually. Subsequently, they participated to an on-line survey developed to gather information about the perceived usefulness of prototypes, in relation to the performed conceptual design activity. Several findings have been obtained from this work, but maybe the most impacting one concerns the different consideration that the two samples of students had about the fidelity of prototypes. Indeed, differently from what recently highlighted in current literature, it emerged that engineering students preferred low-fidelity prototypes. However, other unexpected evidences have been found, which highlight that at least for the considered institution, students still lack a comprehensive understanding of the design-related potentialities of prototypes.

Keywords: Additive manufacturing | CAD | Design | Design education | Engineering education | Prototyping

[16] Puggelli L., Furferi R., Volpe Y., Governi L., A low-cost ChArUco-based 3D scanner for cultural heritage, IOP Conference Series: Materials Science and Engineering, 949(1), (2020). Abstract
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Abstract: In the region of the cultural patrimony, operators use high-resolution orthophotos of paintings for the restoration, monitoring and electronic recording and exhibition purposes. Unfortunately, artworks that are to be restored and/or shown in digital museums are painted on canvas that are far from perfectly planar. Professional documents surrounding an artwork to be preserved in digital collections or museums can therefore be enhanced with information relating to the paintings' 3D structure. This paper proposes both the design of a portable low-cost device that enables the acquisition of 3D geometry of painting and the procedure for triangulation of 3D data. This process uses a set of fiducial markers to set and continuously control the mutual orientation of the laser source and the camera and works accordingly to the principle of laser-camera triangulation.

Keywords: 3D Laser Scanner | Cultural Heritage | Marker Detection | Pose Estimation | Reverse Engineering

[17] Furferi R., Giorgi R., Governi L., Matteini M., Volpe Y., Preface, IOP Conference Series: Materials Science and Engineering, 949(1), (2020).
[18] Guariento L., Buonamici F., Marzola A., Volpe Y., Governi L., Graded Gyroid Structures for Load Bearing Orthopedic Implants, Proceedings of the 2020 IEEE 10th International Conference on "Nanomaterials: Applications and Properties", NAP 2020, (2020). Abstract
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Abstract: The availability of advanced tools able to model complex geometries along with the relaxing of the constraints related to the manufacturing technologies are heavily transforming the design approach in many fields, including healthcare. The focus of this paper is on the optimization of porous lightweight cellular geometries in the orthopedic implants design: lattice structures have proven to fulfill the biological, mechanical, and technological constraints required in designing load bearing devices. The aim is to collect the information provided by the related literature to describe the effects induced by the selection of parameters designing lattice gyroid structures for orthopedic implants.

Keywords: custom metal implant | design for additive manufacturing | gyroid | metallic lattice structures | triply periodic minimal surface

[19] Bartalucci C., Borchi F., Carfagni M., Governi L., Bellomini R., Luzzi S., Çoban N.A., Asensio C., A new curriculum for acoustics experts developed in the frame of the Erasmus+ “noise training” project, Proceedings of 2020 International Congress on Noise Control Engineering, INTER-NOISE 2020, (2020). Abstract
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Abstract: The excessive exposure to noise seriously harms human health and interferes with people's daily activities. The Environment Action Programme of the European Union committed to decrease noise pollution, moving closer to levels recommended by the WHO by 2020. When considering the noise policy instruments, including the legislative, economic and communicative way, the policy applications mostly rely on legislative ones. Although, there is intensive control strategies based on legislations related to environmental noise and legal punishments (as economic way) to the facilities, the public noise complaints have been still increasing. Hence, it is required to increase the capability of staff on the use of communicative instruments of noise management. The Erasmus+ Noise Training Project (NTP) aimed to improve the skills and practices of staff working on environmental noise management (ENM), using innovative methods. Moreover, it improved the sharing of good practices on noise management in audits between European countries to provide the high acoustic quality of urban cities. In the present paper, the comparative analysis on ENM applications between project partner countries (Turkey, Italy and Spain) is described and the final version of the new curriculum focusing on environmental noise is illustrated, together with its transferability potential to additional EU Countries.

[20] Buonamici F., Furferi R., Governi L., Marzola A., Volpe Y., Scene acquisition with multiple 2D and 3D optical sensors: A PSO-based visibility optimization, Sensors (Switzerland), 20(6), (2020). Abstract
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Abstract: Designing an acquisition system for 2D or 3D information, based on the integration of data provided by different sensors is a task that requires a labor-intensive initial design phase. Indeed, the definition of the architecture of such acquisition systems needs to start from the identification of the position and orientation of the sensors observing the scene. Their placement is carefully studied to enhance the efficacy of the system. This often coincides with the need to maximize the surfaces observed by the sensors or some other metric. An automatic optimization procedure based on the Particle Swarm Optimization (PSO) algorithm, to seek the most convenient setting of multiple optical sensors observing a 3D scene, is proposed. The procedure has been developed to provide a fast and efficient tool for 2D and 3D data acquisition. Three different objective functions of general validity, to be used in future applications, are proposed and described in the text. Various filters are introduced to reduce computational times of the whole procedure. The method is capable of handling occlusions from undesired obstacle in the scene. Finally, the entire method is discussed with reference to 1) the development of a body scanner for the arm-wrist-hand district and 2) the acquisition of an internal environment as case studies.

Keywords: 3D scanning | Body scanner | Computer graphics | Optical sensors | PSO | Sensor placement | Visibility analysis

[21] Buonamici F., Furferi R., Governi L., Lazzeri S., McGreevy K.S., Servi M., Talanti E., Uccheddu F., Volpe Y., A practical methodology for computer-aided design of custom 3D printable casts for wrist fractures, Visual Computer, 36(2), 375-390, (2020). Abstract
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Abstract: In recent years, breakthroughs in the fields of reverse engineering and additive manufacturing techniques have led to the development of innovative solutions for personalized medicine. 3D technologies are quickly becoming a new treatment concept that hinges on the ability to shape patient-specific devices.Among the wide spectrum of medical applications, the orthopaedic sector is experiencing the most benefits. Several studies proposed modelling procedures for patient-specific 3D-printed casts for wrist orthoses, for example. Unfortunately, the proposed approaches are not ready to be used directly in clinical practice since the design of these devices requires significant interaction among medical staff, reverse engineering experts, additive manufacturing specialists and CAD designers. This paper proposes a new practical methodology to produce 3D printable casts for wrist immobilization with the aim of overcoming these drawbacks. In particular, the idea is to realize an exhaustive system that can be used within a paediatric environment. It should provide both a fast and accurate dedicated scanning of the hand-wrist-arm district, along with a series of easy-to-use semi-automatic tools for the modelling of the medical device. The system was designed to be used directly by the clinical staff after a brief training. It was tested on a set of five case studies with the aim of proving its general reliability and identifying possible major flaws. Casts obtained using the proposed system were manufactured using a commercial 3D printer, and the device’s compliance with medical requirements was tested. Results showed that the designed casts were correctly generated by the medical staff without the need of involving engineers. Moreover, positive feedback was provided by the users involved in the experiment.

Keywords: CAD | Cast modelling | Orthosis modelling | Personalized medicine | Reverse engineering

[22] Silvaggio R., Curcuruto S., Mazzocchi E., Borchi F., Bartalucci C., Governi L., Carfagni M., Bellomini R., Luzzi S., Colucci G., Cattani G., Gaeta A., Leone G., Di Menno di Bucchianico A., Cusano M., Algieri A., Colombi C., Cuccia E., Dal Santo U., Life Monza: Comparison between ante and post-operam noise and air quality monitoring activities in a Noise Low Emission Zone, Noise Mapping, 7(1), 171-191, (2020). Abstract
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Abstract: LIFE MONZA project (Methodologies fOr Noise low emission Zones introduction And management) aims at defining an easy-replicable method for the identification and management of the Noise Low Emission Zones (Noise LEZ), urban areas subject to traffic restrictions, usually introduced in order to ensure compliance with the air pollutants limit values, prescribed by the European Directive on ambient air quality 2008/50/EC, whose impacts and potential benefits regarding noise issues have been taken into account, tested and analysed in a pilot area of the city of Monza, located in North Italy. Noise LEZ has been established in Libertà district, introducing infrastructural interventions carried out by the municipality (top-down actions) and encouraging an active involvement of the citizens, in the definition of a more sustainable lifestyle (bottom-up actions). The analysis of potential effects on noise reduction due to the Noise LEZ can contribute to the implementation of the EU Directive 2002/49/EC, related to the assessment and management of environmental noise (Environmental Noise Directive – END), which introduces noise action plans, designed to manage noise issues and their effects, suggesting the adoption of urban and mobility planning. Noise and air quality monitoring activities have been carried out in pilot area in ante and post-operam conditions. The monitoring methods, the measurement techniques, the analysis procedures, able to describe the effects due to Noise LEZ establishment, for both the main environmental issues are reported in this paper, as proposals to be applied in other different contexts. Results of monitoring activities highlight a reduction of noise, in term of sound pressure levels, between ante and post-operam, during the day and particularly during the night period, and it is essentially due to the interventions realised. The effect of the Noise LEZ on air pollution seems to be negligible for combustion related pollutant and carbon fractions of PM, due both to the moderate spatial effects of the measures undertaken and confounding factors due to concomitant emission sources and meteorology.

Keywords: Air quality monitoring system | Bottom-up approach | Environmental noise | Low emission zone | Noise monitoring system | Top-down approach | Urban planning

[23] Buonamici F., Carfagni M., Furferi R., Volpe Y., Governi L., Generative design: An explorative study, Computer-Aided Design and Applications, 18(1), 144-155, (2020). Abstract
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Abstract: Generative design tools have recently become an interesting solution to tackle design problems in several technical fields. This article takes into consideration the specific field of mechanical design and aims at describing available generative design solutions capable of dealing with structural optimization problems. The study provides a practical description on the workflow and performances of a specific software system implementing a generative approach for the generation of a set of alternative solutions for a static structural design problem. The software analyzed is Autodesk’s Generative Design, hosted in Fusion 360. The article discusses the functioning of the software and its performances; an enhanced focus on the features oriented to the generation of manufacturable shapes is provided in the text. In order to provide a practical and effective procedure, a literature case study was selected to test the software.

Keywords: Biomimetic Design | CAD | Generative Design | Structural Optimization | Topology Optimization

[24] Buonamici F., Carfagni M., Furferi R., Governi L., Volpe Y., CAD Reconstruction: A Study on Reverse Modelling Strategies, Lecture Notes in Mechanical Engineering, 165-176, (2020). Abstract
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Abstract: Computer Aided reconstruction of mechanical parts nowadays heavily relies on dedicated RE software systems and highly skilled users to be carried out effectively. This paper investigates this scenario in order to identify most limiting factors in the current framework. With this respect, several considerations of general validity are drawn while presenting the problem from a theoretical perspective. A significant test case reconstruction, discussed in depth in the manuscript, is used to provide a practical point of view on real applications and help the reader acquire a hands-on comprehension of the current situation.

Keywords: CAD | CAD reconstruction | Reverse engineering

[25] Puggelli L., Furferi R., Governi L., Low Cost Device to Perform 3D Acquisitions Based on ChAruCo Markers, Lecture Notes in Mechanical Engineering, 189-200, (2020). Abstract
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Abstract: In the field of cultural heritage, operators make use of high resolution orthophotos of paintings both for purposes related to restoration and monitoring of art pieces and for realizing online documentations and exhibitions. Unfortunately, artworks to be restored and/or presented in digital museums are painted on canvas which are far to be perfectly planar. Therefore, technical documentation accompanying an artwork to be stored in digital archives or museums can be enriched by information related to the 3D shape of the canvas. In this paper, both the design of a portable low-cost device that allows the acquisition of the 3D geometry of the painting and a procedure to triangulate 3D data are proposed. Such a procedure, working using the principle of laser-camera triangulation, is based on the use of a set of fiducial markers to set and continuously control the reciprocal orientation of the laser source and of the camera.

Keywords: 3D laser scanner | Cultural heritage | Marker detection | Pose estimation | Reverse engineering

[26] Uccheddu F., Governi L., Carfagni M., A Preliminary 3D Depth Camera-Based System to Assist Home Physiotherapy Rehabilitation, Lecture Notes in Mechanical Engineering, 696-706, (2020). Abstract
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Abstract: Total hip arthroplasty (THA) and total knee arthroplasty (TKA) have been recently heralded as the operations of the Century. Large improvements in mobility and patient-reported outcomes are typically observed compared with the small-to-moderate effects experienced with non-surgical interventions. Following surgery, physiotherapy-led exercise-based rehabilitation is often prescribed to yield better gait-related outcomes. Nevertheless, outpatient rehabilitation is expensive and heavily burden the national health service. When specific machines are not needed during the physiotherapy, patients, if assisted, can perform a home program. The purpose of this paper is to qualitatively investigate the applicability of a self-managed, home-based system for the automated evaluation of a home physiotherapy rehabilitation after TKA and THA. The system leverages the cost effectiveness and the versatility of a RGB-Depth camera system together with a commercial skeleton tracking system to analyse specific exercises. A novel computation of lower limb movements and related angles is proposed to evaluate the quality of the daily exercises. The laboratory experimental campaign, envisaged the analysis of the rotation angles of hips and knees; a lower limb schematic model is considered to estimate both knee and hip angles during ab/adductor and flex/extension movements. A novel real time calculation of the hip bone plane is proposed to assess the joint angles during specific exercises performance. A qualitative data analysis of each exercise has been performed. Results on the system usability in a domestic environment are reported as well as a visual comparison of the analysed output.

Keywords: 3D | Body tracking | RGB-D camera

[27] Santarelli C., Uccheddu F., Argenti F., Alparone L., Carfagni M., Governi L., Shift-Compensated Volumetric Interpolation of Tomographic Sequences for Accurate 3D Reconstruction, IFMBE Proceedings, 76, 312-321, (2020). Abstract
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Abstract: In patients affected by craniosynostosis, i.e. a congenital cranial defect, diagnostic evaluation for a prompt surgical treatment is performed using low-dose three-dimensional computer tomography (CT), characterized by a poor spatial resolution (in terms of slice thickness). The limited number of CT images reduces the accuracy of the 3D reconstruction of the skull and leads to a coarser segmentation and modelling. In this paper, Motion Compensated Frame Interpolation (MCFI) techniques are applied for an effective axial interpolation of tomographic images sequences, with the main objective of obtaining a refined 3D reconstruction. The performance of the proposed method was assessed by using high-resolution CT sequences. After downsampling along the axial direction, the missing slices were recovered by using the proposed algorithm, to obtain an estimate of the original sequence. The experimental results show that the 3D models obtained from the downsampled/interpolated sequence are very close to those obtained from the original one thus providing a high-quality 3D skull reconstruction.

Keywords: 3D modeling | CT slices | Interpolation | Motion compensation

[28] Marzola A., Governi L., Genitori L., Mussa F., Volpe Y., Furferi R., A semi-automatic hybrid approach for defective skulls reconstruction, Computer-Aided Design and Applications, 17(1), 190-204, (2020). Abstract
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Abstract: In cranioplasty surgery, achieving an effective aesthetic shape restoration of the cranial vault is the most important issue to ensure a proper outcome in terms of social and psychological benefits for the patient. To date, the most advanced approach uses CT/MRI data to reconstruct, in a pre-operative stage, the 3D anatomy of the defective skull in order to design a patient-specific prosthesis. In the last years, several techniques have been proposed to improve the applicability of such approach in the clinical practice, but the analysis of the related literature shows still open issues, due to the wide anatomical variability and complexity of the craniofacial anatomy that needs to be retrieved. With the aim to overcome the State-of-the-Art drawbacks, a new semi-automatic hybrid procedure for repairing unilateral or quasi-unilateral (i.e. a single defect slightly passing the sagittal plane) cranial defects is presented. The novel approach is hybrid because a surface interpolation for filling the hole is used together with a template-based reconstruction guided by the healthy counterpart. The procedure, being landmark-independent and avoiding any patch adaptation, represents a valid alternative for the existing approaches also in terms of user's burden, requiring less time consuming and less cumbersome operations. In addition, a new evaluating technique able to measure the symmetry of the reconstruction as well as the continuity between patch and healthy bone is proposed to test the procedure performance. Several test cases have been then addressed to prove the effectiveness and repeatability of the proposed procedure in reconstructing large-size defects of the skull.

Keywords: CAD | Cranioplasty | Reverse Engineering | Skull Reconstruction

[29] Boccini E., Furferi R., Governi L., Meli E., Ridolfi A., Rindi A., Volpe Y., Toward the integration of lattice structure-based topology optimization and additive manufacturing for the design of turbomachinery components, Advances in Mechanical Engineering, 11(8), (2019). Abstract
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Abstract: Used in several industrial fields to create innovative designs, topology optimization is a method to design a structure characterized by maximum stiffness properties and reduced weights. By integrating topology optimization with additive layer manufacturing and, at the same time, by using innovative materials such as lattice structures, it is possible to realize complex three-dimensional geometries unthinkable using traditional subtractive techniques. Surprisingly, the extraordinary potential of topology optimization method (especially when coupled with additive manufacturing and lattice structures) has not yet been extensively developed to study rotating machines. Based on the above considerations, the applicability of topology optimization, additive manufacturing, and lattice structures to the fields of turbomachinery and rotordynamics is here explored. Such techniques are applied to a turbine disk to optimize its performance in terms of resonance and mass reduction. The obtained results are quite encouraging since this approach allows improving existing turbomachinery components’ performance when compared with traditional one.

Keywords: additive manufacturing | lattice structures | Topology optimization | turbomachinery

[30] Servi M., Buonamici F., Furferi R., Governi L., Uccheddu F., Volpe Y., Leng S., Facchini F., Ghionzoli M., Messineo A., Pectus Carinatum: a non-invasive and objective measurement of severity, Medical and Biological Engineering and Computing, 57(8), 1727-1735, (2019). Abstract
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Abstract: To date, standard methods for assessing the severity of chest wall deformities are mostly linked to X-ray and CT scans. However, the use of radiations limits their use when there is a need to monitor the development of the pathology over time. This is particularly important when dealing with patients suffering from Pectus Carinatum, whose treatment mainly requires the use of corrective braces and a systematic supervision. In recent years, the assessment of severity of chest deformities by means of radiation-free devices became increasingly popular but not yet adopted as standard clinical practice. The present study aims to define an objective measure by defining a severity index (named External Pectus Carinatum Index) used to monitor the course of the disease during treatment. Computed on the optical acquisition of the patients’ chest by means of an appositely devised, fast and easy-to-use, body scanner, the proposed index has been validated on a sample composed of a control group and a group of Pectus Carinatum patients. The index proved to be reliable and accurate in the characterization of the pathology, enabling the definition of a threshold that allows to distinguish the cases of patients with PC from those of healthy subjects. [Figure not available: see fulltext.]

Keywords: Index | Optical imaging | Pectus Carinatum | Severity assessment | Three-dimensional

[31] Secciani N., Bianchi M., Ridolfi A., Vannetti F., Volpe Y., Governi L., Bianchini M., Allotta B., Tailor-made hand exoskeletons at the university of florence: From kinematics to mechatronic design, Machines, 7(2), (2019). Abstract
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Abstract: Recently, robotics has increasingly become a companion for the human being and assisting physically impaired people with robotic devices is showing encouraging signs regarding the application of this largely investigated technology to the clinical field. As of today, however, exoskeleton design can still be considered a hurdle task and, even in modern robotics, aiding those patients who have lost or injured their limbs is surely one of the most challenging goal. In this framework, the research activity carried out by the Department of Industrial Engineering of the University of Florence concentrated on the development of portable, wearable and highly customizable hand exoskeletons to aid patients suffering from hand disabilities, and on the definition of patient-centered design strategies to tailor-made devices specifically developed on the different users' needs. Three hand exoskeletons versions will be presented in this paper proving the major taken steps in mechanical designing and controlling a compact and lightweight solution. The performance of the resulting systems has been tested in a real-use scenario. The obtained results have been satisfying, indicating that the derived solutions may constitute a valid alternative to existing hand exoskeletons so far studied in the rehabilitation and assistance fields.

Keywords: Biomechanical engineering | Hand exoskeleton | Kinematic analysis | Mechanism design and optimization | Mechatronics | Wearable robotics

[32] Furferi R., Governi L., Puggelli L., Servi M., Volpe Y., Machine vision system for counting small metal parts in electro-deposition industry, Applied Sciences (Switzerland), 9(12), (2019). Abstract
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Abstract: In the fashion field, the use of electroplated small metal parts such as studs, clips and buckles is widespread. The plate is often made of precious metal, such as gold or platinum. Due to the high cost of these materials, it is strategically relevant and of primary importance for manufacturers to avoid any waste by depositing only the strictly necessary amount of material. To this aim, companies need to be aware of the overall number of items to be electroplated so that it is possible to properly set the parameters driving the galvanic process. Accordingly, the present paper describes a simple, yet effective machine vision-based method able to automatically count small metal parts arranged on a galvanic frame. The devised method, which relies on the definition of a rear projection-based acquisition system and on the development of image processing-based routines, is able to properly count the number of items on the galvanic frame. The system is implemented on a counting machine, which is meant to be adopted in the galvanic industrial practice to properly define a suitable set or working parameters (such as the current, voltage, and deposition time) for the electroplating machine and, thereby, assure the desired plate thickness from one side and avoid material waste on the other.

Keywords: Electro-deposition industry | Image analysis | Item counting device | Machine vision

[33] Leng S., Bici K., Facchini F., Volpe Y., Uccheddu F., Furferi R., Governi L., Carfagni M., Ghionzoli M., Messineo A., Customized Cutting Template to Assist Sternotomy in Pectus Arcuatum, Annals of Thoracic Surgery, 107(4), 1253-1258, (2019). Abstract
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Abstract: Purpose: Pectus arcuatum is an anterior chest wall deformity that requires transverse wedge sternotomy. Determining and delivering the correct cutting angle are crucial for successful correction. This report describes the early clinical experience with a novel cutting template technology able to deliver the optimal cutting angle. Description: From patients’ computed tomographic scans, the optimal cutting angle is obtained using computer-aided design. A template comprising slots tilted at the right cutting angle and a safety block to avoid damaging the posterior periosteum is printed through additive manufacturing. Evaluation: The template allows surgeons to perform a precise wedge sternotomy, safely sparing the posterior periosteum in all patients, without complications. Postoperative chest roentgenograms and clinical photographs demonstrate optimal sternal realignment and cosmetic outcome. In this report, the mean operative time was 110 minutes. All patients were successfully discharged, with a mean length of stay of 4 days. Conclusions: Transverse wedge sternotomy aided by a computer-aided design–devised cutting template may reduce the technical challenge of this procedure, thereby increasing its safety and reducing operative times and hospital stay. Further research on long-term patient outcomes is necessary.

[34] Di Angelo L., Di Stefano P., Governi L., Marzola A., Volpe Y., A robust and automatic method for the best symmetry plane detection of craniofacial skeletons, Symmetry, 11(2), (2019). Abstract
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Abstract: The accurate location of the mid-sagittal plane is fundamental for the assessment of craniofacial dysmorphisms and for a proper corrective surgery planning. To date, these elaborations are carried out by skilled operators within specific software environments. Since the whole procedure is based on the manual selection of specific landmarks, it is time-consuming, and the results depend on the operators' professional experience. This work aims to propose a new automatic and landmark-independent technique which is able to extract a reliable mid-sagittal plane from 3D CT images. The algorithm has been designed to perform a robust evaluation, also in the case of large defect areas. The presented method is an upgraded version of a mirroring-and registration technique for the automatic symmetry plane detection of 3D asymmetrically scanned human faces, previously published by the authors. With respect to the published algorithm, the improvements here introduced concern both the objective function formulation and the method used to minimize it. The automatic method here proposed has been verified in the analysis of real craniofacial skeletons also with large defects, and the results have been compared with other recent technologies.

Keywords: Cranio-maxillofacial | Feature recognition | Medical imaging | Mid-sagittal plane | Symmetry analysis

[35] Carfagni M., Furferi R., Governi L., Santarelli C., Servi M., Uccheddu F., Volpe Y., Metrological and critical characterization of the intel D415 stereo depth camera, Sensors (Switzerland), 19(3), (2019). Abstract
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Abstract: Low-cost RGB-D cameras are increasingly being used in several research fields, including human–machine interaction, safety, robotics, biomedical engineering and even reverse engineering applications. Among the plethora of commercial devices, the Intel RealSense cameras have proven to be among the most suitable devices, providing a good compromise between cost, ease of use, compactness and precision. Released on the market in January 2018, the new Intel model RealSense D415 has a wide acquisition range (i.e., ~160–10,000 mm) and a narrow field of view to capture objects in rapid motion. Given the unexplored potential of this new device, especially when used as a 3D scanner, the present work aims to characterize and to provide metrological considerations for the RealSense D415. In particular, tests are carried out to assess the device performance in the near range (i.e., 100–1000 mm). Characterization is performed by integrating the guidelines of the existing standard (i.e., the German VDI/VDE 2634 Part 2) with a number of literature-based strategies. Performance analysis is finally compared against the latest close-range sensors, thus providing a useful guidance for researchers and practitioners aiming to use RGB-D cameras in reverse engineering applications.

Keywords: Active stereo | Depth camera | Device characterization | Performance comparison | RealSense D415 | Reverse engineering | VDI/VDE standard

[36] Bartalucci C., Borchi F., Carfagni M., Governi L., Luzzi S., Aspuru I., Gaudibert P., Wolfert H., LIFE+2010 QUADMAP Project: Results obtained from the analysis of data collected during the application of the new methodology to the pilot quiet areas, Noise Mapping, 6(1), 22-37, (2019). Abstract
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Abstract: Since the 90s, quiet areas have commonly been considered as places to be acoustically preserved or where acoustic interventions should be implemented to reduce noise levels. With the enforcement of the Environmental Noise Directive in 2002, a formal definition of a 'quiet area in agglomeration' and a 'quiet area in open country' was established. However, many Member States complained about the absence of guidelines regarding the identification and management of quiet areas. The LIFE QUiet Areas Definition and Management in Action Plans (QUADMAP) project started in 2011 to contribute to the Directive's incomplete requirements for quiet areas. The project's main result has been the introduction of a flexible methodology for the selection, analysis and management of quiet areas in agglomeration in which both acoustic and nonacoustic parameters are evaluated. The current paper illustrates the analyses carried out on the data collected during the application of the selection, analysis and management phases of the developed methodology in the different pilot cases selected during the Project. Mentioned analysis are aimed at verifying the benefits of the proposed complementary selection criteria ('relative quiet urban areas' identification criteria and 'homogeneous urban areas' subdivision criteria), at defining the measurement periods most representative of the areas and the acoustic and nonacoustic parameters to be considered as the most significant.

Keywords: data analysis | perception | QUADMAP | quiet areas

[37] Buonamici F., Volpe Y., Furferi R., Carfagni M., Signorini G., Goli G., Governi L., Fioravanti M., Bamboo’s bio-inspired material design through additive manufacturing technologies, Lecture Notes in Civil Engineering, 24, 809-826, (2019). Abstract
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Abstract: Bamboo is one of the longest-used organic raw materials in the tropics for a large number of different purposes in the daily lives of human beings. Because of its excellent physical-mechanical properties, in many parts of the world it is widely used as a structural material, especially for the construction of scaffolding and the construction of buildings. The bamboo can be modelled as a composite material, consisting of a of a parenchyma cells matrix, similar to a foam, reinforced by bundles of fibers associated with vessels. The present work aimed to explore the possibility to design a 3D printed biomimetic composite material able of keeping advantages from the bamboo morphological structure. Samples made of PVA, ABS and PVA + ABS were manufactured using Fused Deposition Modelling and tested under compression and bending conditions. The behavior under compression has shown to depend mainly on the material used while in bending the structure has shown important effects leading the sample made of PVA + ABS to have the same performances of much expensive pure ABS.

Keywords: Additive manufacturing | Bamboo | Structure optimization

[38] Carfagni M., Facchini F., Furferi R., Ghionzoli M., Governi L., Messineo A., Uccheddu F., Volpe Y., Towards a CAD-based automatic procedure for patient specific cutting guides to assist sternal osteotomies in pectus arcuatum surgical correction, Journal of Computational Design and Engineering, 6(1), 118-127, (2019). Abstract
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Abstract: Pectus Arcuatum, a rare congenital chest wall deformity, is characterized by the protrusion and early ossification of sternal angle thus configuring as a mixed form of excavatum and carinatum features. Surgical correction of pectus arcuatum always includes one or more horizontal sternal osteotomies, consisting in performing a V-shaped horizontal cutting of the sternum (resection prism) by means of an oscillating power saw. The angle between the saw and the sternal body in the V-shaped cut is determined according to the peculiarity of the specific sternal arch. The choice of the right angle, decided by the surgeon on the basis of her/his experience, is crucial for a successful intervention. The availability of a patient-specific surgical guide conveying the correct cutting angles can considerably improve the chances of success and, at the same time, reduce the intervention time. The present paper aims to propose a new CAD-based approach to design and produce custom-made surgical guides, manufactured by using additive manufacturing techniques, to assist the sternal osteotomy. Starting from CT images, the procedure allows to determine correct resection prism and to shape the surgical guide accordingly taking into account additive manufacturing capabilities. Virtually tested against three case studies the procedure demonstrated its effectiveness.

Keywords: Biomedical devices | CAD | Design for additive manufacturing | Medical imaging

[39] Cavallo F., Limosani R., Fiorini L., Esposito R., Furferi R., Governi L., Carfagni M., Design impact of acceptability and dependability in assisted living robotic applications, International Journal on Interactive Design and Manufacturing, 12(4), 1167-1178, (2018). Abstract
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Abstract: This paper presents the implementation and investigation of a novel user centred method, adopted to design, develop and test a personal robot system, composed of a mobile robotic platform and a smart environment, for assisting people at home. As robots need to work closely with humans, novel interactive engineering design approaches are required to develop service robots that are adherent to end users’ needs and that can be quickly employed in daily life. Particularly, this paper presents a methodology based on the simultaneous evaluation of dependability and acceptability, thus leading to an innovative approach for metrics and benchmarks that includes not only the main technical attributes of dependability, but also the parameters of acceptability, both implemented via a user-centered design and co-creative approach. Additionally, dependability and acceptability form the basis for defining standardized methodologies to test and evaluate robotic systems in dedicated experimental infrastructures (or robotic facilities), which are conceived to facilitate engineers in their studies and assessments.

Keywords: Acceptability | Companion robot | Dependability | Service robotics | User centred design

[40] Carfagni M., Fiorineschi L., Furferi R., Governi L., Rotini F., The role of additive technologies in the prototyping issues of design, Rapid Prototyping Journal, 24(7), 1101-1116, (2018). Abstract
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Abstract: Purpose: This paper aims to argue about the involvement of additive technologies (ATs) in the prototyping issues of designing. More precisely, it reviews the literature contributions focused on the different perspectives of prototyping activities for design purposes, searching for both available knowledge and research needs concerning the correct exploitation of ATs. Design/methodology/approach: A two-step literature review has been performed. In the first step, general information has been retrieved about prototyping issues related to design. In the second step, the literature searches were focused on retrieving more detailed information about ATs, concerning each of the main issues identified in the previous step. Extracted information has been analyzed and discussed for understanding the actual coverage of the arguments and for identifying possible research needs. Findings: Four generally valid prototyping issues have been identified in the first step of the literature review. For each of them, available information and current lacks have been identified and discussed about the involvement of AT, allowing to extract six different research hints for future works. Originality/value: This is the first literature review concerning AT-focused contributions that cover the complex and inter-disciplinary issues characterizing prototyping activities in design contexts.

Keywords: Additive technologies | Design | Engineering | Engineering design | Prototyping | Rapid prototyping

[41] Volpe Y., Furferi R., Governi L., Uccheddu F., Carfagni M., Mussa F., Scagnet M., Genitori L., Surgery of complex craniofacial defects: A single-step AM-based methodology, Computer Methods and Programs in Biomedicine, 165, 225-233, (2018). Abstract
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Abstract: Background and objective: The purpose of the present paper is to pave the road to the systematic optimization of complex craniofacial surgical intervention and to validate a design methodology for the virtual surgery and the fabrication of cranium vault custom plates. Recent advances in the field of medical imaging, image processing and additive manufacturing (AM) have led to new insights in several medical applications. The engineered combination of medical actions and 3D processing steps, foster the optimization of the intervention in terms of operative time and number of sessions needed. Complex craniofacial surgical intervention, such as for instance severe hypertelorism accompanied by skull holes, traditionally requires a first surgery to correctly “resize” the patient cranium and a second surgical session to implant a customized 3D printed prosthesis. Between the two surgical interventions, medical imaging needs to be carried out to aid the design the skull plate. Instead, this paper proposes a CAD/AM-based one-in-all design methodology allowing the surgeons to perform, in a single surgical intervention, both skull correction and implantation. Methods: A strategy envisaging a virtual/mock surgery on a CAD/AM model of the patient cranium so as to plan the surgery and to design the final shape of the cranium plaque is proposed. The procedure relies on patient imaging, 3D geometry reconstruction of the defective skull, virtual planning and mock surgery to determine the hypothetical anatomic 3D model and, finally, to skull plate design and 3D printing. Results: The methodology has been tested on a complex case study. Results demonstrate the feasibility of the proposed approach and a consistent reduction of time and overall cost of the surgery, not to mention the huge benefits on the patient that is subjected to a single surgical operation. Conclusions: Despite a number of AM-based methodologies have been proposed for designing cranial implants or to correct orbital hypertelorism, to the best of the authors’ knowledge, the present work is the first to simultaneously treat osteotomy and titanium cranium plaque.

Keywords: Additive manufacturing | CAD | Cranium surgery | Image processing

[42] Bartalucci C., Furferi R., Governi L., Volpe Y., A survey of methods for symmetry detection on 3D high point density models in biomedicine, Symmetry, 10(7), (2018). Abstract
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Abstract: Versatile, cheap and non-invasive 3D acquisition techniques have received attention and interest in the field of biomedicine in recent years as the accuracy of developed devices permits the acquisition of human body shapes in detail. Interest in these technologies derives from the fact that they have the potential to overcome some limitations of invasive techniques (CT, X-rays, etc.) and those based on 2D photographs for the acquisition of 3D geometry. However, the data acquired from the 3D scanner cannot be directly used but need to be processed as they consist of 3D coordinates of the acquired points. Therefore, many researchers have proposed different algorithms which recognise the shape of human body and/or its features when starting from a 3D point cloud. Among all possible human body features to be evaluated, symmetry results the most relevant one. Accordingly, this survey systematically investigates the methods proposed in the literature to recognise 2D symmetry by the symmetry line and bilateral symmetry by the symmetry plane. The paper also analyses qualitative comparisons among the proposed methods to provide a guide for both practitioners and researchers.

Keywords: 3D scan | Digital human model | Symmetry line | Symmetry plane

[43] Uccheddu F., Ghionzoli M., Volpe Y., Servi M., Furferi R., Governi L., Facchini F., Lo Piccolo R., McGreevy K.S., Martin A., Carfagni M., Messineo A., A Novel Objective Approach to the External Measurement of Pectus Excavatum Severity by Means of an Optical Device, Annals of Thoracic Surgery, 106(1), 221-227, (2018). Abstract
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Abstract: Background: Current approaches to quantifying the severity of pectus excavatum require internal measurements based on cross-sectional imaging. The aim of this study is to exploit a novel index evaluated on the external surface of the chest with a three-dimensional (3D) optical scanner. Methods: Fifty-one children (41 male, 10 female) between 2 and 17 years of age were evaluated with a 3D optical scanner. Pectus excavatum severity was calculated by using an ad hoc instant 3D scanner and defining an automatic procedure to generate an optical 3D correction index (CI3D). For the latter, an ideal threshold was derived from a statistical analysis, and five blind surveys were collected from pediatric specialists on chest wall deformities. The CI3D was then correlated with blind clinical assessments of PE severity. Results: The cutoff thresholds were determined to optimally discriminate between six degrees of severity of PE patients by a correlation analysis. The correlation coefficient obtained by matching the CI3D with the average subjective severity shows that the proposed method outperforms traditional approaches. Conclusions: The optical 3D index has a good match with the average subjective assessment in distinguishing patients with mild to severe PE. This innovative approach offers several advantages over existing indices, as it is repeatable and does not require cross-sectional imaging. The index might be particularly suitable for monitoring the efficacy of nonoperative treatment and, in the future, for designing an optimal personalized usage of therapeutic devices.

[44] Buonamici F., Furferi R., Governi L., Puggelli L., Volpe Y., Tactile reproduction of paintings: The experience of the Department of Industrial Engineering of Florence, IOP Conference Series: Materials Science and Engineering, 364(1), (2018). Abstract
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Abstract: Within the T-VedO project, financed by Tuscany Region, the Reverse Engineering and Virtual Prototyping Lab team of the Department of Industrial Engineering of Florence (Italy) developed a number of methods for the semiautomatic generation of digital 2.5D models starting from paintings. Once such models are prototyped, they can be used to enhance visually impaired people tactile experience of artworks. Such methods, combined into a systematic procedure, allow to solve most of the typical problems arising when dealing with artistic representation of a painted scene. The present paper presents both an overview of the proposed procedure, including most recent updates, and the results obtained for a selected number of artworks of the Florentine Renaissance.

Keywords: 2.5D models | 3D Reconstruction | CAD

[45] Furferi R., Giorgi R., Governi L., Matteini M., Volpe Y., Preface, IOP Conference Series: Materials Science and Engineering, 364(1), (2018).
[46] Buonamici F., Carfagni M., Furferi R., Governi L., Lapini A., Volpe Y., Reverse engineering modeling methods and tools: a survey, Computer-Aided Design and Applications, 15(3), 443-464, (2018). Abstract
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Abstract: Reverse Engineering (RE) is a long-term goal of engineering and computer science; it aims at the reconstruction of CAD models from measured data by means of 3D mathematical surfaces and geometrical features representing the geometry of a physical part. In the last two decades, reviews and surveys have occasionally covered this topic, but a systematic dissertation of modeling methods from a mechanical engineering point of view is still missing. The purpose of this paper is to fill this gap; starting from a general description of the overall RE framework (acquisition, segmentation, classification, fitting), both an up-to-date survey and a categorization of available modeling techniques and tools working on 3D data are provided. The main aspects of various strategies are discussed as well, in order to highlight strengths and weaknesses characterizing different approaches. Moreover, an overview of commercial software for RE is presented, considering both dedicated solutions and packages supplied as add-on with ‘traditional’ CAD systems. Finally, possible improvements to be addressed by the research in the RE field are discussed, outlining potential future trends that are still to be investigated.

Keywords: 3D modeling | CAD reconstruction | constrained fitting | Reverse engineering | reverse engineering software

[47] Uccheddu F., Carfagni M., Governi L., Furferi R., Volpe Y., Nocerino E., 3D printing of cardiac structures from medical images: an overview of methods and interactive tools, International Journal on Interactive Design and Manufacturing, 12(2), 597-609, (2018). Abstract
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Abstract: The percutaneous interventions in the treatment of structural heart diseases represent nowadays a viable option for patients at high risk for surgery. However, unlike during the traditional open heart surgery, the heart structures to be corrected are not directly visualized by the physician during the interventions. The interpretation of the available medical images is often a demanding task and needs specific skills i.e. clinical experience and complex radiological and echocardiographic analysis. The new trend for cardiovascular diagnosis, surgical planning and intervention is, today, mutually connected with most recent developments in the field of 3D acquisition, interactive modelling and rapid prototyping techniques. This is particularly true when dealing with complex heart diseases since 3D-based techniques can really help in providing an accurate planning of the intervention and to support surgical intervention. To help the research community in confronting with this new trend in medical science, the present work provides an overview on most recent approaches and methodologies for creating physical prototypes of patient-specific cardiac structures, with particular reference to most critical phases such as: 3D image acquisition, interactive image segmentation and restoration, interactive 3D model reconstruction, physical prototyping through additive manufacturing. To this purpose, first, recent techniques for image enhancement to highlight anatomical structures of interest are presented together with the current state of the art of interactive image segmentation. Finally, most suitable techniques for prototyping the retrieved 3D model are investigated so as to derive a number of criteria for manufacturing prototypes useful for planning the medical intervention.

Keywords: 3D modelling | Cardiovascular diseases | Heart | Medical imagery | Rapid prototyping | Surgical planning

[48] Buonamici F., Carfagni M., Furferi R., Governi L., Lapini A., Volpe Y., Reverse engineering of mechanical parts: A template-based approach, Journal of Computational Design and Engineering, 5(2), 145-159, (2018). Abstract
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Abstract: Template-Based reverse engineering approaches represent a relatively poorly explored strategy in the field of CAD reconstruction from polygonal models. Inspired by recent works suggesting the possibility/opportunity of exploiting a parametric description (i.e. CAD template) of the object to be reconstructed in order to retrieve a meaningful digital representation, a novel reverse engineering approach for the reconstruction of CAD models starting from 3D mesh data is proposed. The reconstruction process is performed relying on a CAD template, whose feature tree and geometric constraints are defined according to the a priori information on the physical object. The CAD template is fitted upon the mesh data, optimizing its dimensional parameters and positioning/orientation by means of a particle swarm optimization algorithm. As a result, a parametric CAD model that perfectly fulfils the imposed geometric relations is produced and a feature tree, defining an associative modelling history, is available to the reverse engineer. The proposed implementation exploits a cooperation between a CAD software package (Siemens NX) and a numerical software environment (MATLAB). Five reconstruction tests, covering both synthetic and real-scanned mesh data, are presented and discussed in the manuscript; the results are finally compared with models generated by state of the art reverse engineering software and key aspects to be addressed in future work are hinted at.

Keywords: 3D mesh | CAD reconstruction | CAD template | Constrained fitting | Particle Swarm Optimization | Reverse engineering

[49] Furferi R., Governi L., Uccheddu F., Volpe Y., Computer-aided design tool for GT ventilation system ductworks, Computer-Aided Design and Applications, 15(2), 170-179, (2018). Abstract
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Abstract: The design of gas turbine ventilation systems (VSs) is a lengthy and tedious process, often requiring weeks to refine a single design concept and by additional time to manufacture it. This is particularly true when dealing with structural design since the typical approach followed by main worldwide manufacturing companies is to outsource finite elements analysis and, often, the 3d modelling phase itself. Moreover, the structural design process is iterative: the modeling and finite elements analysis steps are repeated several times whenever a new VS has to be produced. Accordingly, speeding-up the structural design phase is today a crucial issue for gas turbine sector. Keeping the above objective in mind, the present paper proposes a CAD-based tool, implemented in a commercial 3D CAD software package (SolidWorks), supporting and partly automating the complex structural VS design process. The solution suggested in this work consists of the design and implementation of a SolidWorks add-in, called DuctWorks, developed by using C# programming language. Differently from commercially available solutions, the proposed tool is specifically thought keeping in mind the necessity of performing a final structural assessment, which is of utmost importance given the considerable dimensions and stresses this kind of VS are subject to in the specific field of GT and energy production industry. Tested against a set of case studies, DuctWorks proved to be effective in allowing designers to accelerate the ventilation systems design process with excellent results when compared with the traditional design process.

Keywords: CAD tools | FEA | ventilation system

[50] Carfagni M., Facchini F., Furferi R., Ghionzoli M., Governi L., Messineo A., Servi M., Uccheddu F., Volpe Y., A semi-automatic computer-aided method for personalized Vacuum Bell design, Computer-Aided Design and Applications, 15(2), 247-255, (2018). Abstract
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Abstract: Pectus Excavatum, one of the most frequent chest wall deformities, is characterized by a depression of the sternum and costal cartilages. Patients with mild deformities are generally treated conservatively by using the so called Vacuum Bell (VB) i.e. a suction cup to be placed on the patient's sternal region. Three different sizes, as well as a model fitted for young women, of VB are available on the market. Unfortunately, the variability of the surface to be treated, the possible asymmetry of the caved-in area and the prolonged use, can make the device uncomfortable and, in some cases, ineffective for the patient. In order to cope with these issues, the present paper proposes a computer-aided method for customized vacuum bell design to be used by non-expert user, e.g. by medical staff. In particular, the present work entails the development of a system comprising: 1) a dedicated software capable of acquiring the 3D chest geometry - by using a low-cost range sensor, i.e. Kinect v2 - and of processing the point cloud so to generate NURBS surfaces of the chest; 2) a procedural CAD modeling of a personalized VB implemented within Siemens NX 11 CAD environment. Using the devised method, the medical staff is required only to use the 3D scanning system for acquiring the patient chest and to sketch, in a CAD-based interface, the boundary of the area to be treated. Once these tasks are performed, the system automatically builds the personalized VB model, ready to be manufactured.

Keywords: design customization | Procedural CAD modeling | reverse engineering | vacuum bell

[51] Bartalucci C., Borchi F., Carfagni M., Furferi R., Governi L., Lapini A., Volpe Y., Curcuruto S., Mazzocchi E., Marsico G., Luzzi S., Bellomini R., Nizzola C.M., Maggi M., Fasanella A., LIFE MONZA: Project description and actions’ updating, Noise Mapping, 5(1), 60-70, (2018). Abstract
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Abstract: The introduction of Low Emission Zones, urban areas subject to road traffic restrictions in order to ensure compliance with the air pollutants limit values set by the European Directive on ambient air quality (2008/50/EC), is a common and well-established action in the administrative government of cities. The impacts on air quality improvement are widely analysed, whereas the effects and benefits concerning the noise have not been addressed in a comprehensive manner. As a consequence, the definition, the criteria for the analysis and the management methods of a Noise Low Emission Zone are not clearly expressed and shared yet. The LIFE MONZA project (Methodologies fOr Noise low emission Zones introduction And management - LIFE15 ENV/IT/000586) addresses these issues. The first objective of the project, co-funded by the European Commission, is to introduce an easy-replicable method for the identification and the management of the Noise Low Emission Zone, an urban area subject to traffic restrictions, whose impacts and benefits regarding noise issues will be analyzed and tested in the pilot area of the city of Monza, located in Northern Italy. Background conditions, structure, objectives of the project and actions’ progress will be discussed in this article.

Keywords: Bottom-up approach | Environmental noise | Low Emission zones | Low noise paving | Smart noise monitoring system | Top-down approach | Urban planning

[52] Servi M., Volpe Y., Uccheddu F., Furferi R., Governi L., Lazzeri S., A preliminary usability assessment of a 3D printable orthosis design system, Communications in Computer and Information Science, 850, 273-280, (2018). Abstract
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Abstract: The standard treatment for bones fractures entails the use of a tailor-made plaster cast which has several disadvantages: its weight generally causes discomfort, it cannot be taken off without breaking it, it can cause skin rashes and prevents ventilation of the treated area. Therefore, the application of traditional casts to orthopaedics patients does not represent, to date, the best option. To overcome the above-mentioned drawbacks, many strategies based on reverse engineering and additive manufacturing techniques have been proposed and proved to be a valid alternative for producing custom orthoses. Encouraged by the aforementioned results, the authors have developed a low-cost system (called Oplà), specifically dedicated to the hand-wrist-arm district of paediatric patients and capable of creating a 3D CAD model of the orthosis ready to be printed by using additive manufacturing techniques. Such a system comprises a 3D scanner, a control software and a semi-automatic CAD procedure to easily model the orthopaedic device on each patient, without the need of CAD modelling professionals. To evaluate if Oplà can be effectively used by the medical staff to design patient specific 3D printable orthoses in the clinical practice, a preliminary usability assessment has been performed. Five professional nurses from the Meyer Children’s Hospital of Florence (Italy) have been selected and trained in the use of the system. Subsequently, each of them has been asked to perform the whole process for the same patient. Effectiveness, efficiency and satisfaction have been measured in accordance to ISO 9241-11. Results proved that the Oplà system is characterized by a good usability allowing the user to easily and intuitively perform all the tasks in a reasonable time.

Keywords: CAD | Cast modelling | Reverse engineering | Usability

[53] Buonamici F., Carfagni M., Furferi R., Governi L., Saccardi M., Volpe Y., Optimizing fabrication outcome in low-cost FDM machines. Part 2 - tests, Manufacturing Technology, 18(4), 552-558, (2018). Abstract
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Abstract: Several models of FDM machines, characterized by different architecture and hardware components, have flooded the market in the last 5 years. As a result, given the high sensitivity of FDM to the specific machine characteristics, the search for optimal printing parameters is a renown problem. This two-parts paper proposes an easy-to-follow and low-cost procedure for the characterization of any given FDM machine. The method allows the evaluation of the effects of a wide selection of FDM process parameters on the quality of 3D printed parts. The first part focused on the definition of a series of metrics to be measured on a series of test prints to evaluate the quality of the produced parts. The evaluation of seven quality parameters on a single print is made possible thanks to: i) a specifically designed specimen that is made available to the user and ii) a rigorous and repeatable measurement procedure, which are both discussed in the first part of the paper. This second part presents the characterization procedure, the statistical tools used in the experimentation (DOE tools and principles are adopted throughout the experimentation) and provides guidelines to be used for the characterization of any FDM machine. The whole procedure is tested on a desktop FDM machine to demonstrate obtainable results, proving the efficacy of the proposed methodology and highlight strengths and drawbacks of the approach.

Keywords: 3D printing | Additive manufacturing (AM) | Design of experiments (DOE) | Fused deposition modeling (FDM) | Process optimization

[54] Secciani N., Bianchi M., Meschini A., Ridolfi A., Volpe Y., Governi L., Allotta B., Assistive hand exoskeletons: The prototypes evolution at the university of florence, Mechanisms and Machine Science, 68, 307-315, (2018). Abstract
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Abstract: Robotic assistance to hand-impaired people represents an as difficult as important challenge. In this context, the research work of the Department of Industrial Engineering of the University of Florence (UNIFI) led to a tailor-made wearable device for rehabilitative and assistive purposes. In this paper, the synthesis of the development process, sequentially ordered, is given.

[55] Buonamici F., Carfagni M., Furferi R., Governi L., Saccardi M., Volpe Y., Optimizing fabrication outcome in low-cost FDM machines. Part 1-Metrics, Manufacturing Technology, 18(3), 372-378, (2018). Abstract
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Abstract: Several models of FDM machines, characterized by different architecture and hardware components, have flooded the market in the last 5 years. As a result, given the high sensitivity of FDM to the specific machine characteristics, the search for optimal printing parameters is a renown problem. This two-parts paper proposes an easy-to-follow and low-cost procedure for the characterization of any given FDM machine. The method allows the evaluation of the effects of a wide selection of FDM process parameters on the quality of 3D printed parts. The first part focuses on the definition of a series of metrics to be measured on a series of test prints to evaluate the quality of the produced parts. Specifically, several effects are considered: dimensional accuracy, small details, overhang surfaces, ability of printing small holes/thin extrusions and overall quality of the prints. The evaluation of seven quality parameters on a single print is made possible thanks to: i) a specifically designed specimen that is made available to the user and ii) a rigorous and repeatable measurement procedure, which are both discussed in the first part of the paper. The second part presents the characterization procedure, the statistical tools used in the experimentation and provides guidelines to be used for the characterization of any FDM machine. The whole procedure is tested on a desktop FDM machine to demonstrate obtainable results.

Keywords: 3D Printing | Additive Manufacturing (AM) | Design of Experiments (DOE) | Fused Deposition Modeling (FDM) | Process Optimization

[56] Buonamici F., Furferi R., Governi L., Lazzeri S., McGreevy K.S., Servi M., Talanti E., Uccheddu F., Volpe Y., A CAD-based procedure for designing 3D printable arm-wrist-hand cast, Computer-Aided Design and Applications, 16(1), 25-34, (2018). Abstract
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Abstract: Wrist injuries are one of the most common fractures, specifically around 25% of fractures among the pediatric population and up to 18% in the elderly age group are distal radius fractures. To date, the standard treatment entails the use of a tailor-made plaster of Paris cast. Although it is a simple and reliable treatment, it presents several disadvantages: its weight generally causes discomfort, it cannot be taken off without breaking it, it can cause skin rashes and prevents ventilation of the treated area. To overcome the limitations of the above mentioned treatment, 3D printed orthopaedic casts based on reverse engineering (RE) and additive manufacturing (AM) techniques have been proposed in literature. Despite these solutions prove to be a valid alternative to the standard treatment, the clinical use of AM-based devices is not trivial due to the need of expert CAD modelers to design the 3D model of the orthosis starting from the patient’s anatomy 3D acquisition. In this work, the authors identify a systematic procedure to create an orthosis model, compliant with medical guidelines, using common CAD tools. The systematic procedure, even still manually performed, envisages a set of tasks, grouped into five main blocks, that will be easy to be automatized in the future, thus eliminating the necessity of designing expertise to model the orthosis. The proposed procedure allows to design a device composed of two halves, to ease the application, locked through a zip tie-based mechanism. A preliminary ventilation pattern is proposed and tested with a FEM analysis to ensure structural resistance. The procedure has been tested on six case studies: all the orthoses models were correctly generated without major complications and positive user feedbacks were generally obtained throughout the tests.

Keywords: Cad | Cast modeling | Orthosis modelling | Personalized medicine | Reverse engineering

[57] Buonamici F., Furferi R., Genitori L., Governi L., Marzola A., Mussa F., Volpe Y., Reverse engineering techniques for virtual reconstruction of defective skulls: An overview of existing approaches, Computer-Aided Design and Applications, 16(1), 103-112, (2018). Abstract
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Abstract: The surgical process adopted to repair cranial defects using an implant, typically called Cranioplasty, has seen an abrupt increase in recent years due to the introduction of Reverse Engineering (RE) and Additive Manufacturing (AM) techniques. By adopting these techniques, CT/MRI data can be used to reconstruct, in a pre-operative stage, the 3D anatomy of the defective skull in order to design a patient-specific digital model of the prosthesis. The so-designed cranial plate can be then fabricated via AM, in a suitable metal alloy, and implanted. This allows for a perfect fit of the implant during the actual surgery, reducing the risks for the patient and increasing the efficacy of the treatment. This paper reviews existing approaches for the virtual reconstruction of defective skulls, and a basic classification, proposing four different classes of strategies (Mirroring, Surface Interpolation, Template-Based and Slice-based techniques) is provided. The findings of the study suggest that the reconstruction of skull defects is still an open problem, due to the complexities imposed by surface that needs to be retrieved (i.e. the human anatomy). All the presented approaches share weaknesses and limits, which are discussed in the article. Finally, possible directions to improve the existing techniques are briefly presented.

Keywords: Biomedical engineering | Cranioplasty | Reverse engineering | Skull reconstruction

[58] Furferi R., Governi L., Volpe Y., Puggelli L., Carfagni M., Original strategy for avoiding over-smoothing in SFS problem resolution, International Journal of Computational Vision and Robotics, 8(1), 58-73, (2018). Abstract
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Abstract: With the aim of retrieving 3D surfaces starting from single shaded images, i.e. for solving the widely known shape from shading problem, an important class of methods is based on minimisation techniques where the expected surface to be retrieved is supposed to be coincident with the one that minimise a properly developed functional, consisting of several contributions. Despite several different contributes that can be explored to define a functional, the so called 'smoothness constraint' is a cornerstone since it is the most relevant contribute to guide the convergence of the minimisation process towards a more accurate solution. Unfortunately, in case input shaded image is characterised by areas where actual brightness changes rapidly, such a constraint introduces an undesired over-smoothing effect for the retrieved surface. The present work proposes an original strategy for avoiding such a typical over-smoothing effect, with regard to the image regions in which this is particularly undesired such as, for instance, zones where surface details are to be preserved in the reconstruction. The proposed strategy is tested against a set of case studies and compared with other traditional SFS-based methods to prove its effectiveness.

Keywords: 3D model | Minimisation | SFS | shape from shading | Smoothing | Smoothness constraint | variational approach

[59] Uccheddu F., Servi M., Furferi R., Governi L., Comparison of mesh simplification tools in a 3D watermarking framework, Smart Innovation, Systems and Technologies, 76, 60-69, (2018). Abstract
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Abstract: Given a to-be-watermarked 3D model, a transformed domain analysis is needed to guarantee a robust embedding without compromising the visual quality of the result. A multiresolution remeshing of the model allows to represent the 3D surface in a transformed domain suitable for embedding a robust and imperceptible watermark signal. Simplification of polygonal meshes is the basic step for a multiresolution remeshing of a 3D model; this step is needed to obtain the model approximation (coarse version) from which a refinement framework (i.e. 3D wavelet analysis, spectral analysis, …) able to represent the model at multiple resolution levels, can be performed. The simplification algorithm should satisfy some requirements to be used in a watermarking system: the repeatability of the simplification, and the robustness of it to noise or, more generally, to slight modifications of the full resolution mesh. The performance of a number of software packages for mesh simplification, including both commercial and academic offerings, are compared in this survey. We defined a benchmark for testing the different software in the watermarking scenario and reported a comprehensive analysis of the software performances based on the geometric distortions measurement of the simplified versions.

Keywords: 3D watermarking | Mesh comparison | Mesh simplification | Wavelets 3D

[60] Carfagni M., Furferi R., Governi L., Volpe Y., 3D geometry reconstruction from orthographic views: An improved method exploiting shading information, Computers in Industry, 92-93, 137-151, (2017). Abstract
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Abstract: The demand of new tools devoted to integrate aesthetic design into classic parametric CAD suites has undergone a raising interest from the user community. Industrial tools for reconstructing the 3D geometry of an object starting from 2D representations and for surfacing wireframe models according to designers intent, assumed a high relevance and have experienced a steady evolution. The problem of surfacing wireframe models with consistent closing surface patches is still a hot topic in the computer graphics as well as in the industrial field, as demonstrated by a number of recent works. In this paper, authors propose a procedure for enhancing the surfacing process by using shading information, together with the wireframe model. In particular, this work allows to use shading, represented either in a rendered 3D model or sketched by a designer, for retrieving consistent geometrical information related to the 3D object. The procedure is accompanied by some selected case studies, to highlight its strengths and weaknesses.

Keywords: 3D reconstruction | CAD | Hand-drawn sketches | Surfacing | Wireframe model

[61] Conti R., Meli E., Ridolfi A., Bianchi M., Governi L., Volpe Y., Allotta B., Kinematic synthesis and testing of a new portable hand exoskeleton, Meccanica, 52(11-12), 2873-2897, (2017). Abstract
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Abstract: In this research activity, a new methodology for the synthesis of hand exoskeleton mechanisms has been developed and validated through real prototypes. The innovative methodology is based on a new parallel mechanism and has been tested by building a robotic assistive device for hand opening disabilities applied to real cases. The studied robotic orthosis is designed to be a low-cost, adaptable and portable hand exoskeletons to assist people with hand opening disabilities in their activities of daily livings. As regards the methodology for the synthesis of hand exoskeleton mechanism, the authors propose to use a motion capture system to acquire the real hand phalanx trajectories and the geometrical characteristics of the patient’s hand, and to use optimization algorithms to properly defines the novel kinematic mechanism that better fits the finger trajectories. The preliminary testing phase of the prototype on a single patient is concluded; currently, through the collaboration with an Italian rehabilitation center, a group of patients are testing the proposed HES methodology.

Keywords: Hand exoskeleton | Hand opening disabilities | Kinematic synthesis | Portable and wearable robotics

[62] Carfagni M., Furferi R., Governi L., Servi M., Uccheddu F., Volpe Y., On the Performance of the Intel SR300 Depth Camera: Metrological and Critical Characterization, IEEE Sensors Journal, 17(14), 4508-4519, (2017). Abstract
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Abstract: Specifically conceived for applications related to face analytics and tracking, scene segmentation, hand/finger tracking, gaming, augmented reality, and RGB-D cameras are nowadays used even as 3-D scanners. Despite depth cameras' accuracy and precision are not comparable with professional 3-D scanners, they still constitute a promising device for reverse engineering (RE) applications in the close range, due to their low cost. This is particularly true for more recent devices, such as, for instance, the RealSense SR300, which promises to be among the best performing close range depth cameras in the market. Given the potentiality of this new device, and since to date a deep investigation on its performances has not been assessed in scientific literature, the main aim of this paper is to characterize and to provide metrological considerations on the Intel RealSense SR300 depth sensor when this is used as a 3-D scanner. To this end, the device sensor performances are first assessed by applying the existing normative guidelines (i.e. the one published by the Association of German Engineers - Verein Deutscher Ingenieure - VDI/VDE 2634) both to a set of raw captured depth data and to a set acquired with optimized setting of the camera. Then, further assessment of the device performances is carried out by applying some strategies proposed in the literature using optimized sensor setting, to reproduce "real life" conditions for the use as a 3-D scanner. Finally, the performance of the device is critically compared against the performance of latest short-range sensors, thus providing a useful guide, for researchers and practitioners, in an informed choice of the optimal device for their own RE application.

Keywords: depth camera | device characterization | SR300 | structured light | temporal multiplexing | VDI/VDE normative

[63] Bellavia S., Governi L., Papini A., Puggelli L., Regularized Quadratic Penalty Methods for Shape from Shading, Mediterranean Journal of Mathematics, 14(3), (2017). Abstract
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Abstract: Shape from shading (SFS) denotes the problem of reconstructing a 3D surface, starting from a single shaded image which represents the surface itself. Minimization techniques are commonly used for solving the SFS problem, where the objective function is a weighted combination of the brightness error, plus one or more terms aiming to obtain a valid solution. We present a regularized quadratic penalty method where quadratic penalization is used to adaptively adjust the smoothing weights, and regularization improves the robustness and reliability of the procedure. A nonmonotone Barzilai–Borwein method is employed to efficiently solve the arising subproblems. Numerical results are provided showing the reliability of the proposed approach.

Keywords: Barzilai–Borwein method | quadratic penalty methods | quadratic regularization | Shape from shading

[64] Buonamici F., Furferi R., Governi L., Volpe Y., Designing the architecture of a preliminary system for assisting tactile exploration of bas-reliefs, Journal of Design Research, 15(2), 110-127, (2017). Abstract
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Abstract: The participation of blind people (BP) in cultural life can be improved by enhancing methodologies and tools for facilitating the 3D reproduction of artworks and, at the same time, to facilitate their exploration. The creation of integrated systems including not only tactile media such as, for instance, sculptures or bas-reliefs but even a set of tools capable of providing the users with an experience cognitively comparable to the one originally envisioned by the artist, may undoubtedly enhance artworks exploration. The present work aims to design a conceptual system to aid BP in the tactile exploration of bas-reliefs. This conceptual system comprises both a hand-tracking system and an audio device, together with a number of methodologies, algorithms and information related to physical design. The designed layout, preliminarily tested to understand its potential and limits, proved to be a promising first attempt in enhancing the BP exploration experience.

Keywords: 3D reconstruction | Blind people | Hand-tracking system | Tactile bas-relief | Tactile exploration

[65] Carfagni M., Furferi R., Governi L., Servi M., Uccheddu F., Volpe Y., Mcgreevy K., Fast and Low Cost Acquisition and Reconstruction System for Human Hand-wrist-arm Anatomy, Procedia Manufacturing, 11, 1600-1608, (2017). Abstract
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Abstract: 3D body scanners are nowadays used in a range of applications spanning from health, fashion and fitness to reverse engineering applications for robotics and computer vision. Nowadays very good performances are achievable when using commercial 3D body scanners; however, focusing on relative complex shape of some body details, the results still lack precision and acceptable accuracy. Such critical issue remains unsolved also when dealing with the instantaneous acquisition of the hand-wrist-arm (HWA) anatomy. In this paper, we present a new approach that leverages the emerging 3D depth cameras technologies to design a compact low cost 3D dedicated HWA scanner system capable of delivering almost instantaneous full 3D measurement.

Keywords: 3D body scanner | 3D surface | calibration | depth sensors | hand-wrist-arm anatomy

[66] Furferi R., Ganugi L., Giurgola S., Governi L., Puggelli L., Volpe Y., Enhancing Porcelain Whiteware Quality Assessment by Means of Reverse Engineering-based Procedures, Procedia Manufacturing, 11, 1659-1666, (2017). Abstract
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Abstract: During manufacturing, porcelain whiteware changes its shape due to the sintering process. For this reason, leader companies in the field of ceramics apply strict controls on final products in order to reach high quality standards. Typically, three quality parameters are considered: drop of the bottom, bending of the rim and roundness. To date, the assessment of such parameters is still based on visual inspections and manual measurements. In the present paper, authors propose a new quality assessment procedure based on reverse engineering (RE), able to measure the most relevant quality parameters in an effective, reliable and repeatable way.

Keywords: 3D model | 3D reconstruction | 3D scanning | measurement | porcelain | porcelain tableware | quality control | quality parameters | reverse engineering | whiteware

[67] Bartalucci C., Borchi F., Carfagni M., Furferi R., Governi L., Silvaggio R., Curcuruto S., Nencini L., Design of a prototype of a smart noise monitoring system, 24th International Congress on Sound and Vibration, ICSV 2017, (2017). Abstract
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Abstract: The paper describes the new smart noise monitoring system designed and implemented into the project named LIFE15 ENV/IT/000586 "Methodologies fOr Noise low emission Zones introduction And management" (LIFE MONZA). The prototype system has been designed keeping in mind the state of the art systems and the monitoring needs of the LIFE MONZA project. The designed system can be considered as a prototype according to the necessary customization in the designing of connections among the hardware components and in the definition of protocols to manage and post process of collected data. The prototype is expected to undergo quite a long testing phase (up to five years) during and after the LIFE MONZA project duration. In this paper, some details related to the designed network are reported. In particular, a detailed definition of the hardware components and specs, the transmitting data techniques, the specifications necessary to collect raw data are described. Furthermore some new procedures to periodically check the noise monitoring system performance are proposed.

Keywords: Environmental noise | Prototype | Smart monitoring system

[68] Bianchi M., Fanelli F., Conti R., Governi L., Meli E., Ridolfi A., Rindi A., Vannetti F., Allotta B., Design and motion analysis of a wearable and portable hand exoskeleton, Biosystems and Biorobotics, 16, 373-377, (2017). Abstract
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Abstract: The design of an aid for the hand function based on exoskeleton technologies for patients who have lost or injured hand skills, e.g. because of neuromuscular or aging diseases, is one of the most influential challenge in modern robotics to assure them an independent and healthy life. This research activity is focused on the design and development of a low-cost Hand Exoskeleton System (HES) for supporting patients affected by hand opening disabilities during the Activities of Daily Living (ADLs). In addition, the device, able to exert suitable forces on the hand, can be used during the rehabilitative sessions to implement specific tasks useful to restore the dexterity of the user’s hand. The validating and testing phase, conducted in collaboration with the Don Carlo Gnocchi Foundation, showed satisfying results both in terms of portability and wearability which are fundamental requirements for assistance during the Activities of Daily Living (ADLs) and for rehabilitation of people with hand impairments.

[69] Furferi R., Governi L., Uccheddu F., Volpe Y., A RGB-D based instant body-scanning solution for compact box installation, Lecture Notes in Mechanical Engineering, 0, 819-828, (2017). Abstract
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Abstract: Body scanning presents unique value in delivering the first digital asset of a human body thus resulting a fundamental device for a range of applications dealing with health, fashion and fitness. Despite several body scanners are in the market, recently depth cameras such as Microsoft Kinect® have attracted the 3D community; compared with conventional 3D scanning systems, these sensors are able to capture depth and RGB data at video rate and even if quality and depth resolution are not optimal for this kind of applications, the major benefit comes from the overall acquisition speed and from the IR pattern that allows poor lighting conditions optimal acquisition. When dealing with non-rigid bodies, unfortunately, the use of a single depth camera may lead to inconsistent results mainly caused by wrong surfaces registration. With the aim of improving existing systems based on low-resolution depth cameras, the present paper describes a novel scanning system for capturing 3D full human body models by using multiple Kinect® devices in a compact setup. The system consists of an instantaneous scanning system using eight depth cameras, appropriately arranged in a compact wireframe. To validate the effectiveness of the proposed architecture, a comparison of the obtained 3D body model with the one obtained using a professional Konica Minolta Range Seven 3D scanner is also presented and possible drawbacks are hinted at.

Keywords: 3D modelling | Body scanning | Custom Avatar | Depth Camera | Model Fitting

[70] Furferi R., Governi L., Volpe Y., Color matching of fabric blends: Hybrid Kubelka-Munk + artificial neural network based method, Journal of Electronic Imaging, 25(6), (2016). Abstract
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Abstract: Color matching of fabric blends is a key issue for the textile industry, mainly due to the rising need to create high-quality products for the fashion market. The process of mixing together differently colored fibers to match a desired color is usually performed by using some historical recipes, skillfully managed by company colorists. More often than desired, the first attempt in creating a blend is not satisfactory, thus requiring the experts to spend efforts in changing the recipe with a trial-and-error process. To confront this issue, a number of computer-based methods have been proposed in the last decades, roughly classified into theoretical and artificial neural network (ANN)-based approaches. Inspired by the above literature, the present paper provides a method for accurate estimation of spectrophotometric response of a textile blend composed of differently colored fibers made of different materials. In particular, the performance of the Kubelka-Munk (K-M) theory is enhanced by introducing an artificial intelligence approach to determine a more consistent value of the nonlinear function relationship between the blend and its components. Therefore, a hybrid K-M+ANN-based method capable of modeling the color mixing mechanism is devised to predict the reflectance values of a blend.

Keywords: computer-based color assessment | fabric blend | Kubelka-Munk theory | neural networks | spectrophotometer

[71] Furferi R., Governi L., Volpe Y., Carfagni M., Carded tow real-time color assessment: A spectral camera-based system, Sensors (Switzerland), 16(9), (2016). Abstract
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Abstract: One of the most important parameters to be controlled during the production of textile yarns obtained by mixing pre-colored fibers, is the color correspondence between the manufactured yarn and a given reference, usually provided by a designer or a customer. Obtaining yarns from raw pre-colored fibers is a complex manufacturing process entailing a number of steps such as laboratory sampling, color recipe corrections, blowing, carding and spinning. Carding process is the one devoted to transform a “fuzzy mass” of tufted fibers into a regular mass of untwisted fibers, named “tow”. During this process, unfortunately, the correspondence between the color of the tow and the target one cannot be assured, thus leading to yarns whose color differs from the one used for reference. To solve this issue, the main aim of this work is to provide a system able to perform a spectral camera-based real-time measurement of a carded tow, to assess its color correspondence with a reference carded fabric and, at the same time, to monitor the overall quality of the tow during the carding process. Tested against a number of differently colored carded fabrics, the proposed system proved its effectiveness in reliably assessing color correspondence in real-time.

Keywords: Carding process | Color assessment | Spectral camera sensor | Spectrophotometry

[72] Buonamici F., Carfagni M., Furferi R., Governi L., Volpe Y., Are we ready to build a system for assisting blind people in tactile exploration of bas-reliefs?, Sensors (Switzerland), 16(9), (2016). Abstract
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Abstract: Nowadays, the creation of methodologies and tools for facilitating the 3D reproduction of artworks and, contextually, to make their exploration possible and more meaningful for blind users is becoming increasingly relevant in society. Accordingly, the creation of integrated systems including both tactile media (e.g., bas-reliefs) and interfaces capable of providing the users with an experience cognitively comparable to the one originally envisioned by the artist, may be considered the next step for enhancing artworks exploration. In light of this, the present work provides a description of a first-attempt system designed to aid blind people (BP) in the tactile exploration of bas-reliefs. In detail, consistent hardware layout, comprising a hand-tracking system based on Kinect® sensor and an audio device, together with a number of methodologies, algorithms and information related to physical design are proposed. Moreover, according to experimental test on the developed system related to the device position, some design alternatives are suggested so as to discuss pros and cons.

Keywords: 3D reconstruction | Blind people | Hand-tracking system | Kinect sensor

[73] Luzzi S., Bellomini R., Natale R., Bartalucci C., Borchi F., Carfagni M., Governi L., Importance of public participation in END implementation: Some experiences from Italian agglomerates and infrastructures, Proceedings of the INTER-NOISE 2016 - 45th International Congress and Exposition on Noise Control Engineering: Towards a Quieter Future, 1248-1255, (2016). Abstract
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Abstract: Information, communication and participation are important keywords for a correct and effective implementation of Directive 2002/49/EC, the Environmental Noise Directive (END). Following the article 9 of END, information to the public must be ensured by Member States as the strategic noise maps are adopted and the action plans are drawn up. Data should be made fully available and disseminated to the public, information must be clear, comprehensible and accessible. Sometimes the participation of public is needed to make the best choice among different solutions for actions of noise reduction plan and acoustic quality improvement in strategic action plans, sometimes the public can be involved, as main stakeholder, in the definition of policies for noise control at local level including regulations for the correct use of entertainment ares and quiet areas as well. In this paper a general review of different scenarios where participation of the public is preferable since it can give crucial contributions is shown. The review is integrated by some examples of good and useful information and participation activities derived by strategic noise mapping and action plans implementation for agglomerates and infrastructures of transport.

Keywords: Information END | Participation

[74] Furferi R., Carfagni M., Volpe Y., Governi L., Nanomaterials-based heating devices for cultural heritage application: A patent survey, Micro and Nanosystems, 8(1), 3-12, (2016). Abstract
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Abstract: Conservation practices are aimed to implement minimal, targeted and less in-vasive treatments. The conservation profession’s challenges and best practices are therefore becoming more global and mobile, especially when dealing with treatments involving temperature (e.g. painting conservation). The near future of heating devices in art conservation will be with mobile, versatile, accurate and cost effective “smart” devices. For these reasons, the design and manufacturing of heating mats for applications in the Cultural Heritage field moved from early concepts mainly based on electrically heated mats towards more accurate thermo-electrical mild heating devices, especially based on nanomaterials. Despite great scientific efforts have been spent in the last years to create more efficient devices for conservation, there is still room for practically implementing them and, moreover, for protecting new concepts by patenting them. To help the scientific community in getting an overview on the patent state of the art on this important sector, the present work is aimed to provide a survey of patents related to nanomaterials-based heaters to be adopted for artworks conservation. Starting from early works, the paper explores recent patents by selecting the domains referred to nanotechnology sector that are mainly relevant for the heating devices field.

Keywords: Carbon nanotubes | Heating mates | Nanomaterials | Nanotechnology | Paintings conservation | Patents

[75] Carfagni M., Governi L., Volpe Y., Development of a software platform for collaborative MCAD based shoe design, 2008 IEEE International Technology Management Conference, ICE 2008, (2016). Abstract
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Abstract: In this paper a novel approach, enabling rapid time to market and making shoe collaborative design effectively possible, will be presented. The solution suggested in this work consists of two elements: first, the implementation of a SolidWorks add-on called SYS (SYstem Shoe) whose main goal is to provide a widespread CAD software packages with specific features for shoe design; secondarily the development of a web platform, capable to communicate with and control the SYS add-on. This platform provides the unique opportunity of making the entire system (installed on a server PC) available to external users (small factories concurring to the shoe production chain), without the need of a CAD software own installation. The scenario in which the described system is supposed to work consists of a inter-company network with a main node equipped with the web-CAD platform. This main node acts as a server towards the peripheral nodes (clients: shoe assembly and component-making companies).

Keywords: collaborative design | reverse engineering | Shoe design

[76] Borchi F., Carfagni M., Governi L., Curcuruto S., Silvaggio R., Bellomini R., Luzzi S., Licitra G., Palazzuoli D., Melloni A., LIFE+2008 HUSH project results: A new methodology and a new platform for implementing an integrated and harmonized noise Action Plan and proposals for updating Italian legislation and Environmental Noise Directive, Noise Mapping, 3(1), 71-85, (2016).
[77] Aspuru I., Garcia I., Bartalucci C., Borchi F., Carfagni M., Governi L., Bellomini R., Luzzi S., Wolfert H., Gaudibert P., LIFE+2010 QUADMAP project: A new methodology to select, analyze and manage Quiet Urban Areas defined by the European Directive 2002/49/EC, Noise Mapping, 3(1), 120-129, (2016). Abstract
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Abstract: Concerning quiet areas, the definition provided by the Environmental Noise Directive (END) is intended to preserve the acoustic environment in those areas where it is considered good, according to general indicators and limits. However, the END is not clear enough to allow appropriate assessment and management in urban environments. The aim of QUADMAP project was to deliver a method and guidelines for the identification, delineation, characterization, improvement and management of Quiet Urban Areas (QUAs) as defined by the END. The Project also wanted to help clarify the definition of a QUA, its meaning and its added value for cities in terms of health, safety and lowering stress levels. In this article, after an introduction of the current European scenario on QUAs, the main aspects of the methodology introduced for the selection, analysis and management of QUAs are described. Eventually, the major results achieved by the Project, in terms of the guideline on QUAs, the implemented interventions and the achieved benefits, are reported and discussed.

Keywords: Action plan | Environmental noise | Noise mapping | Quiet areas | Soundscape

[78] Bartalucci C., Borchi F., Carfagni M., Governi L., Bellomini R., Luzzi S., Asdrubali F., D'Alessandro F., Schiavoni S., Contributions to end interpretation and implementation from the Italian case studies of eu funded projects hush, nadia and quadmap, ICSV 2016 - 23rd International Congress on Sound and Vibration: From Ancient to Modern Acoustics, (2016). Abstract
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Abstract: The European Noise Directive 2002/49/EC (END) provides indications and recommendations about noise mapping, action planning, quiet areas and the communication and dissemination towards citizens. However, for several items only definitions and general indications are made available, without giving specific suggestions about how to deal with them in practice. In this article the main contributions to END interpretation and implementation from the Italian case studies of EU funded projects HUSH, NADIA and QUADMAP are described. LIFE+2008 HUSH (Harmonization of Urban Noise reduction Strategies for Homogeneous action plans) project aimed at giving a contribution to the harmonization of the National and European legislations, regarding urban noise management tools, allowing a definition of coherent procedures able to comply the commitments introduced by National laws and by the END. Starting from the methodology defined and the interventions realized in two pilot areas in Florence, proposals for revision of National legislation and END have been provided, for supporting competent authorities and policy makers. In the LIFE+2009 NADIA (Noise Abatement Demonstrative and Innovative Actions and information to the public) project methods and procedures to achieve the END requirements have been developed, aiming the following main objectives: to improve the methodologies for the realization of noise mappings and action plans, with a particular focus on road traffic noise, to increase the awareness of citizens and of potential stakeholders by focused communication and dissemination activities and to assess the technical and economic feasibility of best practices in tackling road traffic noise. LIFE+2010 QUADMAP project (QUiet Areas Definition and Management in Action Plans) has proposed a method and guidelines for the selection, analysis and management of Quiet Urban Areas (QUAs) as introduced by the END.

[79] Carfagni M., Furferi R., Governi L., Puggelli L., Volpe Y., Two simple yet effective strategies for avoiding over-smoothing in SFS problem, Journal of Computer Science, 12(3), 128-140, (2016). Abstract
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Abstract: Minimization techniques are widely used for retrieving a 3D surface starting from a single shaded image i.e., for solving the shape from shading problem. Such techniques are based on the assumption that expected surface to be retrieved coincides with the one that minimize a properly developed functional, consisting of several contributions. Among the possible contributes defining the functional, the so called "smoothness constraint" is always used since it guides the convergence of the minimization process towards a more accurate solution. Unfortunately, in areas where actually brightness changes rapidly, it also introduces an undesired over-smoothing effect. The present work proposes two simple yet effective strategies for avoiding the typical over-smoothing effect, with regards to the image regions in which this effect is particularly undesired (e.g., areas where surface details are to be preserved in the reconstruction). Tested against a set of case studies the strategies prove to outperform traditional SFS-based methods.

Keywords: 3D model | Minimization | Shape from shading | Smoothing | Smoothness constraint | Variational approach

[80] Allotta B., Conti R., Governi L., Meli E., Ridolfi A., Volpe Y., Development and experimental testing of a portable hand exoskeleton, IEEE International Conference on Intelligent Robots and Systems, 2015-December, 5339-5344, (2015). Abstract
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Abstract: In this paper, the development and the experimental testing phases of an innovative assistive device for hand disabilities are presented. This robotic device is based on an parallel kinematic chain applied to a single phalanx architecture and it is designed to be extremely portable to easily assist people with physical disabilities in their everyday lives. Focusing on patients with hand opening disabilities, the authors have developed a model-based methodology which starting from the motion capture of the patient fingertip trajectories is able to define the mechanism that better fits with such trajectories. The authors have validated the proposed innovative mechanism by developing a portable Hand Exoskeleton System (HES) prototype and performing a suitable preliminary testing campaign. The testing phase of the real prototype on a group of patients is currently ongoing.

Keywords: Exoskeletons | Joints | Kinematics | Mathematical model | Prototypes | Solid modeling | Trajectory

[81] Furferi R., Governi L., Volpe Y., Machine vision-based pilling assessment: A review, Journal of Engineered Fibers and Fabrics, 10(3), 79-93, (2015). Abstract
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Abstract: Pilling is an undesired defect of textile fabrics, consisting of a surface characterized by a number of roughly spherical masses made of entangled fibers. Mainly caused by the abrasion of fabric surface occurring during washing and wearing of fabrics, this defect needs to be accurately controlled and measured by companies working in the textile industry. Pilling measurement is traditionally performed using manual procedures involving visual control of fabric surface by human experts. Since the early nineties, great efforts in developing automatic and non-intrusive methods for pilling measurement have been made all around the world with the final aim of overcoming traditional, visual-based and subjective procedures. Machine Vision proved to be among the best options to perform such defect assessment since it provided increasingly performing measurement equipment and tools, serving the purpose of automatic control. In particular, a relevant number of interesting works have been proposed so far, sharing the idea of helping (or even replacing) traditional measurement methods using image processing-based ones. The present work provides a rational and chronological review of the most relevant methods for pilling measurement proposed so far. This work serves the purposes of 1) understanding whether today’s automatic machine vision-based pilling measurement techniques are ready for supplanting traditional pilling measurement and 2) providing textile technology researchers with a bird’s eye view of the main methods studied to confront with this problem.

Keywords: Artificial neural networks | Fabrics | Image processing | Machine vision | Pilling assessment | Review

[82] Allotta B., Conti R., Governi L., Meli E., Ridolfi A., Development and testing of a low cost wearable and portable hand exoskeleton based on a parallel mechanism, Proceedings of the ASME Design Engineering Technical Conference, 5A-2015, (2015). Abstract
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Abstract: In this research work, the authors developed and tested a low cost wearable and portable hand exoskeleton to assist people with physical disabilities in their everyday lives. Focusing on hand opening disabilities, the proposed actuated orthoses could support and enable daily gestures such as shacking hands or grasping objects. The Hand Exoskeleton System (HES) prototype is based on a cable-driven architecture applied to a single-phalanx mechanism. The preliminary prototype of the system has been successfully built and is currently under testing with a patient to verify its performance from a patient viewpoint.

[83] Bartalucci C., Borchi F., Carfagni M., Governi L., Zonfrillo G., Bellomini R., Wolfert H., Aspuru I., Gaudibert P., Life+2010 QUADMAP project (QUiet areas definition and management in action plans): Results of post operam data analysis and the optimized methodology, 22nd International Congress on Sound and Vibration, ICSV 2015, (2015). Abstract
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Abstract: The EU Directive 49/2002/EC on Environmental Noise refers to Quiet Urban Areas (QUAs) as places whose acoustic climate should be preserved because a noise indicator is lower than a threshold established by each Member State. This definition appears to be extremely generic and doesn't provide usable procedures to be applied in each Country. Proposing a solution to overcome the lack of harmonized methodologies for QUAs is the main aim of QUADMAP (QUiet Areas Definition and Management in Action Plans) Project. The results of the Project will facilitate urban planners to apply standard procedures for identification, delimitation and prioritization of QUAs. The Project has a high level of demonstrativeness guaranteed by the fact that the proposed methodology has been tested in a number of pilot areas in Florence (Italy), Bilbao (Spain) and Rotterdam (The Netherlands). The Project started on 1st September 2011 and lasts three years and half. At the beginning of 2013 the harmonized methodology has been defined. The proposed procedures have been tested since February 2013 in all pilot cases and the methodology has been improved, in line with experiences gained during data collection and analysis of the ante-operam scenarios. Since the beginning of 2014, the realization of interventions started, following indications coming from endusers questionnaires, expert analysis, technicians and application of complementary criteria. In the pilot areas of Bilbao interventions have been completed by June 2014, while in Florence and Rotterdam they have been concluded by the end of the same year. In the meantime, post-operam data collection and analysis have started. In this paper results of the post operam data analysis are described and compared with those obtained on the ante-operam phase. Moreover, the main innovative elements introduced in the optimized methodology are illustrated.

[84] Buonamici F., Furferi R., Governi L., Volpe Y., Making blind people autonomous in the exploration of tactile models: A feasibility study, Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 9176, 82-93, (2015). Abstract
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Abstract: Blind people are typically excluded from equal access to the world’s visual culture, thus being often unable to achieve concrete benefits of art education and enjoyment. This is particularly true when dealing with paintings due to their bi-dimensional nature impossible to be explored using the sense of touch. This may be partially overcome by translating paintings into tactile bas-reliefs. However, evidence from recent studies suggests that the mere tactile exploration is often not sufficient to fully understand and enjoy bas-reliefs. The integration of different sensorial stimuli proves to dramatically enrich the haptic exploration. Moreover, granting blind people the possibility of autonomously accessing and enjoying pictorial works of art, is undoubtedly a good strategy to enrich their exploration. Accordingly, the main aim of the present work is to assess the feasibility of a new system consisting of a physical bas-relief, a vision system tracking the blind user’s hands during “exploration” and an audio system providing verbal descriptions. The study, supported by preliminary tests, demonstrates the effectiveness of such an approach capable to transform a frustrating, bewildering and negative experience (i.e. the mere tactile exploration) into one that is liberating, fulfilling, stimulating and fun.

Keywords: Blind people | Cultural heritage | Hand tracking | Human-computer interaction

[85] Furferi R., Governi L., Volpe Y., Methods for predicting spectral response of fibers blends, Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 9281, 79-86, (2015). Abstract
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Abstract: Textile companies usually manufacture fabrics using a mix of pre-colored fibers according to a traditional recipe based on their own experience. Unfortunately, mainly due to the fibers dyeing process, the colorimetric distance between the obtained fabric and the desired one results unsatisfactory with respect to a colorimetric threshold established by the technicians. In such cases, colorists are required to slightly change the original recipe in order to reduce the colorimetric distance. This trial and error process is time-consuming and requires the work of highly skilled operators. Computer-based color recipe assessment methods have been proposed so far in scientific literature to address this issue. Unlikely, many methods are still far to be reliably predictive when the fabric is composed by a high number of components. Accordingly, the present work proposes two alternative methods based on Kubelka-Munk and subtractive mixing able to perform a reliable prediction of the spectrophotometric response of a fabric obtained by means of any variation of a recipe. The assessment performed on a prototypal implementation of the two methods demonstrates that they are suitable for reliable prediction of fabric blends spectral response.

Keywords: Computer-based color assessment | Fabric blend | Kubelka-Munk theory | Spectro-photometer

[86] Volpe Y., Governi L., Furferi R., Computer-aided design of new service doors for recreational vehicles, International Journal of Mechanics, 9, 26-35, (2015). Abstract
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Abstract: Recreational vehicles (camper, vans and motorhomes) are equipped with service doors to access to specific areas such as water tank or luggage zone. As the state-of-the-art technology stands at present, two different typologies of service doors are manufactured: doors with plastic frames, obtained by injection molding, and doors with aluminum frames realized by extruded bars. Plastic frame-based doors are characterized by concealed hinges (i.e. hinges integrated in the frame), therefore resulting aesthetically pleasant to the final user. Unfortunately, they are basically produced in standard dimensions due to the complexity and costs of injection molding process; as a consequence the number of available measures in the market is really limited. Quite the reverse, aluminum frame-based doors can be produced in customizable formats by adjusting the bars length. The main drawbacks of this second typology of doors are that the cutting and bending machines, used to produce them, need to be periodically tuned in order to take into account possible environmental thermal variations and, moreover, in order to achieve 180° opening, the hinges are required to stick out the wall. Moving from these considerations, this work proposes a CAD/CAE-based design of an innovative service door based on a modular design where frames consist of extruded plastic bars, cut in required length, which are capable to comprise concealed hinges. Accordingly, the new door designed in the present work brings together the advantages offered by the standard solutions pushing forward the RV door technological state of the art.

Keywords: CAD | CAE | Service doors | Slam test

[87] Volpe Y., Governi L., Furferi R., A computational model for early assessment of padded furniture comfort performance, Human Factors and Ergonomics In Manufacturing, 25(1), 90-105, (2015). Abstract
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Abstract: Seating comfort has always been a primary issue in the design of padded furniture pieces. This paper proposes a computational model-basedmethodology to assist the designer willing to take comfort into account as a primary requirement for padded furniture design. The methodology is based on a virtual mannequin, which can be tailored to reproduce the average target user, and the complete assembly of the main elements composing a typical armchair. Since contact pressure distribution is recognized to be strictly related to seating comfort perception, the contact occurring between these components, during the seating act, was simulated by means of a finite element solver and the resulting contact pressure distribution was computed. Several simulations were carried out with reference to a set of different armchair layout and materials; the obtained results showed a reasonable agreement with the experimental data recorded by means of a capacitive mat. Finally, by using an exemplificative criterion based on comfort-related pressure distribution parameters, the authors demonstrate the possibility of selecting the best-performing configurations prior to building a physical prototype. The proposed approach, tested on a complex seat and a wide range of possiblematerials, can be considered of general applicability since 1) the virtual mannequin, as opposed to what is reported in a number of scientific works, is not requested to closely resemble a single test subject, and 2) the selected seat structure and seat components encompass the most commonly used ones for this kind of product so that a few generally applicable considerations can be drawn.

Keywords: Comfort assessment | Computational model | Padded furniture design | Seat experiments | Seat modeling

[88] Governi L., Furferi R., Volpe Y., Puggelli L., Vanni N., Tactile exploration of paintings: An interactive procedure for the reconstruction of 2.5D models, 2014 22nd Mediterranean Conference on Control and Automation, MED 2014, 14-19, (2014). Abstract
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Abstract: Cultural heritage is often not accessible to visually impaired and blind people, hardly ever when dealing with two-dimensional artworks like, for instance, paintings. In fact, despite tactile reproductions of 3D works of art such as sculptures or architectural models are quite common, a real barrier between blind people and pictorial artworks still exists, obviously due to their intrinsic 2D format. The translation of paintings into bas-relieves is recognized to be one of the most effective ways for breaking down such a barrier, thus allowing a sensible improvement in blind people's accessibility to this kind of works of art. Moving from these considerations, in this work the authors want to provide a bird's eye view on a new methodology for the semi-automatic generation of tactile 3D models starting from paintings, in particular those characterized by single-point perspective. The proposed method relies on an interactive Computer-based modelling procedure, which is conceived to be simple and effective to use. The procedure, which has been implemented into a prototypal software package, has been effectively used to 'translate' a set of paintings from the Italian Renaissance.

[89] Furferi R., Governi L., Vanni N., Volpe Y., Tactile 3D bas-relief from single-point perspective paintings: A computer based method, Journal of Information and Computational Science, 11(16), 5667-5680, (2014). Abstract
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Abstract: Visually impaired and blind people are more excluded from equal access to the world's visual culture, thus being often unable to achieve concrete benefits of art education or to experience the life enhancing power of art. Despite the fact that all over the world several initiatives based on the interaction with sculptures and tactile three-dimensional reproductions or architectural aids on scale have been devised, a "sensory barrier" between blind people and pictorial artworks still exists, obviously due to their intrinsic 2D format. Translation of paintings into tactile models in the form of bas-reliefs is recognized to be one of the most effective ways for breaking down such a barrier, thus allowing a tangible improvement of the blind people's accessibility to artworks. In the recent years, computer aided technologies for automatic or semi-automatic translation of paintings into tactile models dramatically have been devised all over the world, thus improving blind people's accessibility to artworks. Inspired by some of these impressive works, this paper describes a user-driven methodology for the semi-automatic generation of tactile 3D models starting from paintings. Particularly devoted to the reconstruction of pictorial artworks characterized by single-point perspective, the proposed method relies on an interactive Computer-based modelling procedure. The method has been tested on two masterpieces of the Italian Renaissance period.

Keywords: 3d computer based modelling | Blind people | Haptic exploration | Single-point perspective | Tactile bas-relief

[90] Furferi R., Carfagni M., Governi L., Volpe Y., Bogani P., Towards automated and objective assessment of fabric pilling, International Journal of Advanced Robotic Systems, 11, (2014). Abstract
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Abstract: Pilling is a complex property of textile fabrics, representing, for the final user, a non-desired feature to be controlled and measured by companies working in the textile industry. Traditionally, pilling is assessed by visually comparing fabrics with reference to a set of standard images, thus often resulting in inconsistent quality control. A number of methods using machine vision have been proposed all over the world, with almost all sharing the idea that pilling can be assessed by determining the number of pills or the area occupied by the pills on the fabric surface. In the present work a different approach is proposed: instead of determining the number of pills, a machine vision-based procedure is devised with the aim of extracting a number of parameters characterizing the fabric. These are then used to train an artificial neural network to automatically grade the fabrics in terms of pilling. Tested against a set of differently pilled fabrics, the method shows its effectiveness.

Keywords: Computational vision | Image processing | Machine vision system | Neural networks | Pilling | Textile industry

[91] Governi L., Furferi R., Puggelli L., Volpe Y., A practical approach based on shape from shading and fast marching for 3D geometry recovery under oblique illumination, Applied Mechanics and Materials, 472, 503-509, (2014). Abstract
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Abstract: Design of new industrial objects characterized by high stylistic content often starts from sketches or images of the product to be, subsequently, represented in a 3D digital form by using CAD software. To speed up this phase, a number of methods for automatic or semi-automatic translation of sketches or images into a 3D model have been devised all over the world also for reverse engineering purposes. When the image shading is a crucial information for recovering the final 3D shape, Fast Marching is recognized to be among the best method to date, especially for frontally illuminated scenes. Unfortunately, such a method cannot be directly applied when object illumination in the considered image is oblique. The present work is aimed to propose a simple, but effective, approach for recovering 3D shape of objects starting from single side illuminated scenes i.e. for solving non-eikonal SFS problems. Tested against a set of case studies, the method proved its effectiveness. © (2014) Trans Tech Publications, Switzerland.

Keywords: Digital design | Fast marching | Intelligent manufacturing | Oblique illumination | Shape from shading

[92] Bellomini R., Luzzi S., Carfagni M., Borchi F., Governi L., Bartalucci C., Life+2010 Quadmap Project (Quiet Areas Definition and Management in Action Plans): The methodology tested and optimized in pilot cases in Florence, Rotterdam and Bilbao, Proceedings of Forum Acusticum, 2014-January, (2014). Abstract
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Abstract: Current practices about selection, assessment and management of Quiet Areas in EU Countries, though regulated by the EU Directive 49/2002/EC on Environmental Noise, appear to be extremely fragmented and inhomogeneous. In fact, each country during past years adopted a set of strategies strictly related to specific contexts. Proposing a solution to overcome the lack of harmonized methodologies for Quiet Areas is the main aim of QUADMAP (QUiet Areas Definition and Management in Action Plans) project. The project has a high level of demonstrativeness guaranteed by the fact that the methodology proposed for identification, delimitation and prioritization of QUAs will be tested on a number of case study areas. In particular, it will be applied in a set of pilot cases in Italy, Spain, and in The Netherlands. The project started on 1st September 2011 and lasts three years. At the beginning of 2013 the harmonized methodology has been defined. The proposed procedure has been tested since February 2013 in all pilot cases and optimized according to data collected in the pilot cases. In this paper the optimization procedures are described, with particular attention to those developed in the period April-June 2014.

[93] Carfagni M., Bartalucci C., Borchi F., Governi L., Petrucci A., Weber M., Aspuru I., Bellomini R., Gaudibert P., Life+2010 quadmap project (quiet areas definition and management in action plans): The new methodology obtained after applying the optimization procedures, 21st International Congress on Sound and Vibration 2014, ICSV 2014, 3, 2576-2583, (2014). Abstract
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Abstract: Current practices about selection, assessment and management of Quiet Areas in EU Countries, though regulated by the EU Directive 49/2002/EC on Environmental Noise, appear to be extremely fragmented and inhomogeneous. In fact, each country during past years adopted a set of strategies strictly related to their specific contexts. Proposing a solution to overcome the lack of harmonized methodologies for Quiet Areas is the main aim of QUADMAP (QUiet Areas Definition and Management in Action Plans) project. The results of the project will facilitate urban planners to apply standard procedures for identification, delimitation and prioritization of Quiet Urban Areas. The project has a high level of demonstrativeness guaranteed by the fact that proposed methodology will be tested on a number of case study areas. In particular, it will be tested in a set of pilot cases in Italy, Spain, and in The Netherlands. The project started on 1st September 2011 and lasts three years. At the end of 2012 the harmonized methodology has been defined. The proposed procedures have been tested since February 2013 in all pilot cases and, recently, the methodology has been optimized, in line with experiences gained during data collection within the pilot cases and analysis of the ante-operam scenarios. In this paper the optimization procedures are described with regards to these experiences gained in the pilot cases.

[94] Furferi R., Governi L., Volpe Y., Puggelli L., Vanni N., Carfagni M., From 2D to 2.5D i.e. from painting to tactile model, Graphical Models, 76(6), 706-723, (2014). Abstract
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Abstract: Commonly used to produce the visual effect of full 3D scene on reduced depth supports, bas relief can be successfully employed to help blind people to access inherently bi-dimensional works of art. Despite a number of methods have been proposed dealing with the issue of recovering 3D or 2.5D surfaces from single images, only a few of them explicitly address the recovery problem from paintings and, more specifically, the needs of visually impaired and blind people. The main aim of the present paper is to provide a systematic method for the semi-automatic generation of 2.5D models from paintings. Consequently, a number of ad hoc procedures are used to solve most of the typical problems arising when dealing with artistic representation of a scene. Feedbacks provided by a panel of end-users demonstrated the effectiveness of the method in providing models reproducing, using a tactile language, works of art otherwise completely inaccessible.

Keywords: 2.5D model | Minimization techniques | Shape From Shading | Tactile model

[95] Rocco F., Lapo G., Luca P., Volpe Y., Improved interactive method for reco-vering 2.5D models from single images, Journal of Computer Science, 10(10), 2141-2154, (2014). Abstract
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Abstract: In the last years the development of interactive Computer-based methods for building virtual and physical 2.5D models from single shaded images faced with an exponential growth. In particular, a wide range of methods based on image processing-based procedures and on Shape From Shading (SFS) can be documented. On the basis of the most favorable techniques devised in literature, the present work describes an improved interactive method capable of retrieving 2.5D models using image shading information. The pro-posed method performs a SFS-based reconstruction where (1) the overall geometry of the expected surface is first recovered and (2) the final 2.5D reconstruction is obtained by minimizing a suitable functional using the rough surface as an initialization function. The method improves previous interactive works by introducing a novel two-step rough surface recovery and a new definition of a functional to be minimized for solving the SFS problem. Tested against a set of case studies the proposed method proves to be effective in providing 2.5D models. © 2014 Science Publications.

Keywords: 2.5D model | Image processing | Interactive reconstruction | Minimization | Shape from shading

[96] Markevicius T., Furferi R., Olsson N., Meyer H., Governi L., Carfagni M., Volpe Y., Hegelbach R., Towards the development of a novel CNTs-based flexible mild heater for art conservation, Nanomaterials and Nanotechnology, 4(1), (2014). Abstract
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Abstract: Mild heating devices currently available to conservators are still limited in terms of precision, versatility, mobility, accessibility and cost. Moreover, they lack a range of operational features, such as low power requirements, efficient power use, temperature stability and uniform heat distribution. Carbon nanotubebased technologies can provide a wide range of technical solutions for overcoming these limitations, thereby allowing the development of more precise, flexible and portable heating devices. This work describes the design of an innovative carbon nanotube-based intelligent mobile accurate thermo-electrical mild heating device, to be used in the art conservation field. The device consists of three different types of flexible heating mats with different designs (opaque and ultra-thin/woven and breathable/transparent) and different operational and physical properties. The entire heating system is completed by a control unit that controls, monitors and registers the heating and by a power supply unit. First tests performed on a series of prototypes of the designed heaters showed that the device was able to convey uniform heating on different working materials, thus proving to be effective for thermal consolidation. © 2014 The Author(s).

Keywords: Carbon nanotubes | Cultural heritage | Mild heating devices

[97] Volpe Y., Furferi R., Governi L., A computer-based system for dyeing leather patch edges, International Journal of Computer Aided Engineering and Technology, 6(2), 139-158, (2014). Abstract
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Abstract: The visual appearance of seamless dyed edges of luxury leather goods represents a key issue in terms of quality grading since a high-quality leather has to be characterised by homogeneously coloured and shaped edges with uniform ink thickness. Despite a huge literature produced by scientific and technical community to automate many leather manufacturing processes, since leather patches are often characterised by a free-form shape, any attempt of automating leather edges dyeing produced unsatisfactory and inaccurate results. In order to overcome the drawbacks of the existing approaches, the main objective of the present work is to provide a computer-based system for automatically dyeing leather patches edges. The described system includes: 1) a machine vision (MV) hardware equipment, consisting of both illumination and a high resolution acquisition device, devoted to patches edge detection; 2) a pantograph whose dyeing tool is moved along leather edges; 3) a series of computer-based methods for the automatic extraction of the leather patches outlines. Extensive testing performed using the developed machine demonstrated its effectiveness in delivering fast, automatic and high quality edge finishing in a reliable and repeatable way. © 2014 Inderscience Enterprises Ltd.

Keywords: Leather dyeing | Machine vision | Process automation

[98] Volpe Y., Furferi R., Governi L., Tennirelli G., Computer-based methodologies for semi-automatic 3D model generation from paintings, International Journal of Computer Aided Engineering and Technology, 6(1), 88-112, (2014). Abstract
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Abstract: Over the last few years, technologies like 3D scanning and rapid prototyping provided an extraordinary boost in improving reproductions of 3D artworks, like sculptures and historical buildings, all over the world. Physical 3D reproduction of subjects represented in paintings, is recognised to be one of the best ways to allow visually impaired people to enjoy such kind of artworks. However, the use of advanced technologies with the aim of realising 3D models starting from paintings has not been satisfactorily investigated yet. Though a number of algorithms coming from computer vision science exist to cope with similar issues, the specific problem of producing a 3D representation which is targeted at blind people tactile exploration has been only marginally investigated. Starting from these considerations, this work presents 1) a quite extensive review of the criteria proposed in literature for producing tactile models suitable for blind people and 2) four alternative computer-based methods for semi-automatic generation of tactile 3D models starting from RGB digital images of paintings. The outcomes of this study contribute new information to the field of visually impaired user-oriented 3D reconstruction and clearly indicate the strategy to be adopted in order to produce a meaningful reproduction of a bi-dimensional piece of artwork. © 2014 Inderscience Enterprises Ltd.

Keywords: 3D computer-based modelling | Blind | Haptic exploration | Visually impaired

[99] Governi L., Carfagni M., Furferi R., Puggelli L., Volpe Y., Digital Bas-Relief Design: A Novel Shape from Shading-Based Method, Computer-Aided Design and Applications, 11(2), 153-164, (2014). Abstract
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Abstract: Design of products characterized by high stylistic content and organic shapes in the form of bas-relief (e.g. fashion accessories, commemorative plaques and coins) is traditionally performed starting from handmade drawings or photographs that are manually reproduced by highly skilled craftsmen such as sculptors and engravers and finally digitized by means of 3D scanning. Several Computer-based procedures have been devised with the aim of speeding up this process, which is considerably time consuming, subjective and costly; these are mainly based on image processing techniques such as embossing, enhancement, histogram equalization or dynamic range, also implemented in CAD-based commercial software. However, these approaches are characterized by several limitations preventing them from providing a "correct" final geometry. In view of that, the present work describes a novel method for the creation of digital bas-reliefs from a single image using a Shape From Shading (SFS) based approach with interactive initialization. Image processing-based techniques and minimization SFS methods are first used in order to retrieve a rough version of the objective surface; successively, this is used as initialization for the final reconstruction algorithm. Tested on a set of case studies, the method proved to be effective in providing satisfactory digital bas-relief from single images. © 2013 © 2013 CAD Solutions, LLC.

Keywords: digital bas-relief | image processing | shape from shading | shape retrieval

[100] Governi L., Furferi R., Palai M., Volpe Y., Detecting intersection zones in thread-like 3D voxel clouds: a novel algorithm based on neighbourhood tracing, Journal of Information and Computational Science, 10(8), 2187-2197, (2013). Abstract
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Abstract: 3D topological segmentation entails the partition of 3D clouds of connected voxels (e.g. 3D images) into sets of entities, connected by a series of nodes. Especially for thread-like structures (e.g. blood vessels, proteins, piping and voxel-based 3D sketches), nodes detection and, more in particular, identification of entities converging in a node may be considered a crucial issue to correctly interpret the "structure" of the analysed object. The main objective of the present work is to describe an innovative algorithm able to determine the possible intersection zones between groups of voxels composing a thread-like 3D voxel cloud. The devised algorithm is based on a multi-directional ray-tracing procedure applied, for each voxel of the 3D dataset, with reference to a set of directions defined by an appropriate 3D neighbourhood domain. The thread-like structure thicknesses, coming from the ray-trace analysis, are estimated along different directions. Finally, the set of thicknesses is analysed by means of a statistical approach so that voxels, possibly belonging to intersection zones, can be identified. The proposed algorithm demonstrated its effectiveness in a number of test cases. Copyright © 2013 Binary Information Press.

Keywords: 3D topology | Local thickness | Ray-trace analysis | Voxel graphics

[101] Furferi R., Governi L., Volpe Y., Carfagni M., Design and assessment of a machine vision system for automatic vehicle wheel alignment, International Journal of Advanced Robotic Systems, 10, (2013). Abstract
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Abstract: Wheel alignment, consisting of properly checking the wheel characteristic angles against vehicle manufacturers' specifications, is a crucial task in the automotive field since it prevents irregular tyre wear andaffects vehicle handling and safety. In recent years, systems based on Machine Vision have been widely studied in order to automatically detect wheels' characteristic angles. In order to overcome the limitations of existing methodologies, due to measurement equipment being mounted onto the wheels, the present work deals with design and assessment of a 3D machine vision-based system for the contactless reconstruction of vehicle wheel geometry, with particular reference to characteristic planes. Such planes, properly referred to as a global coordinate system, are used for determining wheel angles. The effectiveness of the proposed method was tested against a set of measurements carried out using a commercial 3D scanner; the absolute average error in measuring toe and camber angles with the machine vision system resulted in full compatibility with the expected accuracy of wheel alignment systems. © 2013 Furferi et al.

Keywords: Machine vision | Stereovision | Wheel alignment

[102] Furferi R., Governi L., Volpe Y., Image processing-based method for glass tiles colour matching, Imaging Science Journal, 61(2), 183-194, (2013). Abstract
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Abstract: Furniture glass tiles are increasingly used for covering walls and facades or for conferring fashionable aesthetical properties to buildings. Companies that produce furniture glass tiles of a desired colour are devoted to performing a colour comparison between the manufactured glass tiles and the ones desired by a customer, or provided by a catalogue. Still today, such a comparison, known as 'colour matching', is mainly performed by company experts by means of a visual inspection, thus leading to a subjective and qualitative colour assessment. A number of methods for colour matching have been afforded in the literature in several industrial fields such as textile, plastics or food; unfortunately, to the best of author's knowledge, no practical method for glass tiles colour matching has been devised until today. The present work provides an image processing-based method capable of carrying out nonpatterned glass tiles colour matching. The method is devised using an appositely developed hardware so as to extract a series of statistical data from scanned images of 10 mm sized glass tiles and, on the basis of the definition of two novel colour distance formulas, endows with colour matching. The achieved colour matching performance agrees in 91% of tests with expertperformed colour classification. The provided formulas are meant to be of general usage for assessing glass tiles colour matching. © RPS 2013.

Keywords: Colour gaussian | Colour matching | Glass | Image processing | Mahalanobis

[103] Bartalucci C., Borchi F., Carfagni M., Governi L., Bellomini R., Luzzi S., Natale R., LIFE+2010 QUADMAP project (QUiet areas definition and management in action plans): The proposed methodology and its application in the pilot cases of Firenze, 42nd International Congress and Exposition on Noise Control Engineering 2013, INTER-NOISE 2013: Noise Control for Quality of Life, 6, 4840-4849, (2013). Abstract
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Abstract: Current practices about selection, assessment and management of QUAs (Quiet Urban Areas) in EU Countries, though regulated by the EU Directive 49/2002/EC on Environmental Noise (commonly abbreviated END), appear to be extremely fragmented and inhomogeneous. In fact, each country during past years adopted a set of strategies strictly related to their specific contexts. Proposing a solution to overcome the lack of harmonized methodologies for QUAs is the main aim of QUADMAP (QUiet Areas Definition and Management in Action Plans) project. The results of the project will facilitate urban planners to apply standard procedures for identification, delimitation and prioritization of QUAs. The project has a high level of demonstrativeness guaranteed by the fact that the proposed methodology will be tested on a number of case study areas. In particular, it will be tested on a set of pilot cases in Italy, Spain, and The Netherlands. The project started on 2011, September the 1st and lasts three years. At the beginning of 2013 the first version of the harmonized methodology has been defined. The project partners have being testing the procedures making up such a methodology since February 2013 in all pilot cases. The proposed methodology and an overview of the available results in pilot areas selected in the city of Firenze are presented in this paper.

Keywords: Environmental noise directive | Noise | Quiet areas | Soundscape

[104] Governi L., Furferi R., Puggelli L., Volpe Y., Improving surface reconstruction in shape from shading using easy-to-set boundary conditions, International Journal of Computational Vision and Robotics, 3(3), 225-247, (2013). Abstract
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Abstract: Minimisation techniques are commonly adopted methodologies for retrieving a 3D surface starting from its shaded representation (image), i.e., for solving the widely known shape from shading (SFS) problem. Unfortunately, depending on the imaged object to be reconstructed, retrieved surfaces often results to be completely different from the expected ones. In recent years, a number of interactive methods have been explored with the aim of improving surface reconstruction; however, since most of these methods require user interaction performed on a tentative reconstructed surface which often is significantly different from the desired one, it is advisable to increase the quality of the surface, to be further processed, as much as possible. Inspired by such techniques, the present work describes a new method for interactive retrieving of shaded object surface. The proposed approach is meant to recover the expected surface by using easy-to-set boundary conditions, so that the human-computer interaction primarily takes place prior to the surface retrieval. The method, tested on a set of case studies, proves to be effective in achieving sufficiently accurate reconstruction of scenes with both front and side illumination. © 2013 Inderscience Enterprises Ltd.

Keywords: Boundary conditions | Computational vision | Human-computer interaction | Minimisation techniques | SFS | Shape from shading

[105] Carfagni M., Furferi R., Governi L., Volpe Y., A vane-motor automatic design procedure, International Journal on Interactive Design and Manufacturing, 7(3), 147-157, (2013). Abstract
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Abstract: Because of their features, pneumatic motors are often preferred to their electrical counterparts in a number of industrial applications. In spite of their growing diffusion, to the best of authors knowledge, a well-established design procedure is still missing due to the large number of factors (e.g. friction, fluid-dynamic losses, etc.) introducing non idealities in the motor behaviour. Moving from these considerations, this work aims to illustrate the development of a design methodology, implemented in the form of a prototypal software tool, capable of automatically define all the necessary constructive parameters of vane motors on the basis of a required characteristic curve and to considerably speed-up the whole design process. The methodology is based on three main elements: an experimental-mathematical model obtained by means of a DoE approach; a search algorithm meant to identify the constructive solution best matching the design target; a parametric CAD model which is directly driven by the constructive parameters provided by the mathematical model. The presented methodology, applied to the development of a set of pneumatic vane motors, led to the manufacturing of units fulfilling the design target within an error lower than 3 %, thereby demonstrating the effectiveness of the proposed approach. © 2012 Springer-Verlag France.

Keywords: Air motor | Automatic design | Optimization | Parametric modelling

[106] Governi L., Furferi R., Palai M., Volpe Y., 3D geometry reconstruction from orthographic views: A method based on 3D image processing and data fitting, Computers in Industry, 64(9), 1290-1300, (2013). Abstract
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Abstract: Industrial esthetic designers typically produce hand-drawn sketches in the form of orthographic projections. A subsequent translation from 2D-drawings to 3D-models is usually necessary. This involves a considerably time consuming process, so that some automation is advisable. Common approaches to this "reconstruction problem" start directly from "exact" 2D vector representations or try to vectorize 2D raster images prior to the reconstruction phase. These approaches, however, typically fail to deal with free form geometries like the ones commonly found in esthetic industrial design. This work presents a new methodology suitable for free form geometries, comprising the generation and processing of a 3D voxel image obtained from a hand drawing, the creation of a set of 3D curves fitting the voxel image and the automatic generation of surface patches on the resulting curve network. Several case studies are also presented in order to emphasize and discuss strengths and weaknesses of the proposed method. © 2013 Elsevier B.V. All rights reserved.

Keywords: 3D geometry fitting | 3D reconstruction | Industrial design | Orthographic views | Voxel imaging

[107] Bartalucci C., Borchi F., Carfagni M., Governi L., Weber M., Wolfert H., Quiet areas definition and management in action plans: General Overview, 41st International Congress and Exposition on Noise Control Engineering 2012, INTER-NOISE 2012, 7, 5554-5560, (2012).
[108] Governi L., Furferi R., Volpe Y., A genetic algorithms-based procedure for automatic tolerance allocation integrated in a commercial variation analysis software, Journal of Artificial Intelligence, 5(3), 99-112, (2012). Abstract
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Abstract: In the functional design process of a mechanical component, the tolerance allocation stage is of primary importance to make the component itself responding to the functional requirements and to cost constraints. Present state-of-the-art approach to tolerance allocation is based on the use of Statistical Tolerance Analysis (STA) software packages which, by means of Monte Carlo simulation, allow forecasting the result of a set of user-selected geometrical and dimensional tolerances. In order to completely automate and optimize this process, this work presents a methodology to allow an automatic tolerance allocation, capable to minimize the manufacturing cost of a single part or assembly. The proposed approach is based on the Monte Carlo method to compute the statistical distribution of the critical to quality characteristics and uses an optimization technique based on Genetic Algorithms. The resulting procedure has been integrated in an off-the-shelf variation analysis software: eM-TolMate (by Siemens AG). Both the description of the optimization algorithm and some practical applications are presented in order to demonstrate the effectiveness of the proposed methodology. © 2012 Asian Network for Scientific Information.

Keywords: Functional design | Genetic algorithms | Monte carlo method | Tolerance allocation

[109] Markevicus T., Olsson N., Carfagni M., Furferi R., Governi L., Puggelli L., IMAT project: From innovative nanotechnology to best practices in art conservation, Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 7616 LNCS, 784-792, (2012). Abstract
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Abstract: The research and development of new conservation materials and instrumentation and the integration of contemporary science into the discipline are of fundamental importance in formulating best practices in conservation and preserving cultural heritage assets. With this goal in mind in November 2011, the IMAT project (Intelligent Mobile Accurate Thermo-Electrical mild heating device) was launched under the European Commission's 7th Framework Program (FP7) for research. During the three-year length of the project, coordinated by the University of Florence, a European consortium of researchers representing expertise in conservation, nanotechnology, and thermo-electrical engineering will develop nanotechnology for the IMAT devices specifically designed for highly accurate mild heating in conservation of artworks and other cultural heritage assets. © 2012 Springer-Verlag Berlin Heidelberg.

Keywords: conservation | IMAT | mild heating | nanotubes

[110] Carfagni M., Furferi R., Governi L., Volpe Y., Tennirelli G., Tactile representation of paintings: An early assessment of possible computer based strategies, Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 7616 LNCS, 261-270, (2012). Abstract
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Abstract: In recent years, a number of works meant to define the criteria for translating two-dimensional art into tactile representation, to be benefit of blind and visually impaired people. Due to technology-related limitations, however, these studies mainly investigated only some kinds of possible representations (e.g. tactile diagrams). This work deals with the analysis of 4 alternative translation strategies, implemented using computer-based tools, to determine the most effective one in delivering blind people a correct perception of pictorial artworks. The outcomes of the study contribute new information to the field of tactile paintings for blind and visually impaired individuals by testing the response of a panel of potential users. © 2012 Springer-Verlag Berlin Heidelberg.

Keywords: blind | Computer-based 3D modeling | haptic exploration | tactile artwork | visually impaired

[111] Borchi F., Carfagni M., Governi L., The H.U.S.H. project - An harmonized methodology for action planning, Proceedings - European Conference on Noise Control, 345-350, (2012). Abstract
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Abstract: The H.U.S.H. LIFE+ project (Harmonization of Urban noise reduction Strategies for Homogeneous action plans), approved by European Commission into the LIFE+2008 financial program, moves from the evidence that harmonization of noise action planning methods is needed in all the European countries where a former Legislation about noise planning was in force when Environmental Noise Directive (END) 49/2002/EC, [1], was adopted. The general aim is harmonizing national noise management standards with END for obtaining homogeneous noise Action Plans, in order to provide a contribution to the more general need of transposing, implementing and enforcing a common or harmonized environmental legislation among EU countries. Specific aims of the project are: to point out unsolved conflicts among current standards at Regional, National and European level; to define common methods for designing strategic and specific solutions; to define a new development system for action planning; to design guidelines for action plans implementation. In a previous publication, [2], the results of data collection were described and some critical issues were pointed out about noise mapping and action planning procedures. Based on this outcome, during the HUSH project, an harmonized methodology has been developed for noise mapping and action planning and it is presented in this work. © European Acoustics Association.

[112] Furferi R., Governi L., Volpe Y., A novel method for ring spinning performance evaluation based on Computer Aided analysis of yarn geometry, International Journal of Mechanics, 6(4), 212-221, (2012). Abstract
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Abstract: Yarn hairiness and yarn hand represent key parameters to be strictly assessed and controlled in textile processes since they affect many aspects such as visual appearance of yarns (and consequently of fabrics), handle, thermal insulation, pleasant sensation during touch and smoothness. This is particularly true when fancy yarns, such as jaspè or frisè, are produced using ring spinning: colored natural fibers composing the fancy yarns are required to protrude, to some extent, from the yarn core, usually composed by synthetic material, so as to impart the desired properties in terms of smoothness and luster. With the aim of realizing highest performing fancy yarns, a novel ring spinning system, equipped with a double drafting unit, has been realized by Università di Firenze thanks to the contribute of Tuscany Region (Italy). Once the fancy yarns are obtained, the performance of this innovative ring spinning is evaluated by means of a Computer Aided analysis of yarn geometry able to provide a novel measurement of yarn hairiness and to quantitatively define a yarn hand-related parameter. A Machine Vision system has been devised in order to acquire yarn geometry so that an accurate analysis can be carried out. Such computer aided-based analysis allows to determine two parameters used for determining hairiness and hand: the "equivalent yarn hairiness" and the "yarn hand index". Such parameters are evaluated for yarns obtained using both the innovative and a conventional ring spinning machine so that the yarns quality can be effectively compared. Based on the obtained results that the proposed method proved to be suitable and effective for evaluating yarn hairiness within an average error of about 5.40% with respect to the Uster tester. Furthermore, a good correlation (93%) between objective and subjective assessment of yarn hand was reached.

Keywords: Computer Aided analysis | Image processing | Yarn geometry | Yarn hairiness | Yarn hand

[113] Furferi R., Governi L., Volpe Y., Modelling and simulation of an innovative fabric coating process using artificial neural networks, Textile Research Journal, 82(12), 1282-1294, (2012). Abstract
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Abstract: A polyurethane-based fabric coating process requires a series of parameters to be set in order to meet the desired quality of the final product. Usually, the optimal setting of such parameters is performed by means of experimental tests, based on the experience of trained operators. The lack of understanding of the interaction between the coating process parameters and the final quality properties of the coated fabric encourages the development of predictive models. The main aim of the present work is to provide a predictive model of a particular coating process for forecasting the final characteristics of a coated fabric, based on the process parameters. The devised model, based on artificial neural networks, is trained and validated using a wide experimental database created with reference to an innovative coating process. Once simulated with new process parameters, the model proves to be capable of determining the best possible process parameter values to obtain the preferred coated fabric properties. By employing the developed model, a series of charts are also built that can be used to provide technicians with a practical tool for effectively selecting the process parameters. © 2012, SAGE Publications. All rights reserved.

Keywords: coatings | systems engineering | testing

[114] Furferi R., Governi L., Palai M., Volpe Y., The reconstruction problem: Integrating different approaches into a systematic procedure for pseudo wireframe retrieval, Journal for Geometry and Graphics, 15(1), 79-91, (2011). Abstract
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Abstract: Nowadays three-dimensional Computer Aided modeling is of out-standing importance in the mechanical design process since it impacts on several issues like visualization, simulation, machining, etc. Anyway, multi orthographic view engineering drawings have been widely used up to latest decade and still are, so they play an essential role in traditional engineering. The conversion from 2D drawings to 3D CAD models is still a key task in a wide range of applications. In order to cope with this issue a number of works have been proposed in the last decades, providing a series of methodologies for solving the reconstruction prob-lem. On the basis of such methodologies the main aim of the present paper is to suggest a comprehensive, orderly, unambiguous and automatic procedure meant to help researchers and practitioners who want to deal with the reconstruction problem. The procedure, by using an appropriate formal mathematic language, systematize and integrates some of the methods proposed so far. © 2011 Heldermann Verlag.

Keywords: 3D reconstruction | Computational geometry | Computer aided design | Engineering drawings | Or-thographic projections | Pseudo-wireframe

[115] Carfagni M., Governi L., Nunziati M., Offline continuous adaptation of templates for signature identification, International Journal of Mathematical Models and Methods in Applied Sciences, 5(6), 1003-1010, (2011). Abstract
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Abstract: Automatic on-line signature identification is a procedure which allows a machine to identify a subject among a cohort of individuals by using only the subject's signature. The following paper deals with features and models required in order to allow a machine to learn and discriminate people on the basis of such a biometric trait. The proposed solution presents a neural network based framework for template adaptation which has demonstrated to improve the resilience of a system, when it has to face with forgeries, that is, fake signatures which are used in order to attack the system and grant unauthorized access to services. The proposed framework provides an improved security level of 35% with respect to non adapted systems.

Keywords: Adaptation | Artificial neural networks | Identification | Signature

[116] Furferi R., Governi L., Palai M., Volpe Y., Artificial vision based inspection of marbled fabric, Applications of Mathematics and Computer Engineering - American Conference on Applied Mathematics, AMERICAN-MATH'11, 5th WSEAS International Conference on Computer Engineering and Applications, CEA'11, 93-98, (2011). Abstract
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Abstract: Marbling effect on fabrics is a relevant aesthetic feature, increasing its diffusion specially in the field of textiles for technical applications. The fabric aesthetic anisotropy, characterizing the marbling effect, has a strong impact on the perceived quality: a high-quality marbled fabric to be used in automotive textiles, for instance, is characterized by a tiny quantity of veins and spotted areas. A large amount of "veins" and/or discolored areas may induce a customer to consider the fabric as "defected". In common practice, the identification of whether the fabric is defective or not is performed by human experts by means of visual inspection. As a consequence, fabric inspection is performed in a qualitative and unreliable way; thereby the definition of a method for the automatic and objective inspection is advisable. On the basis of the state of the art, the present work aims to describe a computer-based approach for the automated inspection of marbling effect on fabrics, resulting in the classification of fabrics into three quality classes. The devised apparatus is composed by a machine vision system provided with an image processing-based software. The processing software is able to determine the anisotropy of a fabric using edge segmentation and image entropy and defining a "fabric entropy curve" The proposed method proves to be able to classify the fabrics into the correct quality class in 90% of the cases, with respect to the selection criteria provided by human operators.

Keywords: Artificial vision | Edge detection | Fabric inspection | Image entropy | Marbling effect

[117] Furferi R., Governi L., Palai M., Volpe Y., From unordered point cloud to weighted B-spline - A novel PCA-based method, Applications of Mathematics and Computer Engineering - American Conference on Applied Mathematics, AMERICAN-MATH'11, 5th WSEAS International Conference on Computer Engineering and Applications, CEA'11, 146-151, (2011). Abstract
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Abstract: Digital applications such as CG, CAD and GIS are based on vectorial data since all the information about shape, size, topology etc. are provided in such kind of data representation rather than raster one. Turning raster images into vector ones is a key issue which has been addressed by a number of authors but still far to be exhaustively worked out. Especially in the case of 2D images representing technical drawings, fitting analytical curves to point clouds (pixel sets) is a critical matter. The present paper provides a novel approach to fit unordered point cloud data. Such an approach integrates a PCA-based method, for detecting the main local directions of the point cloud and to order the points, with and a weighted approximation of a B-spline curve to the original data, based on pixel gray levels. The methodology, tested against alternative techniques based on Least Square (LS) B-spline approximation and on image thinning, proved to be effective in preserving the original shape according to human perception.

Keywords: Curve reconstruction | Image processing | PCA | Unorganized points | Weighted least-squares

[118] Carfagni M., Furferi R., Governi L., Palai M., Volpe Y., "3D reconstruction problem": An automated procedure, Applications of Mathematics and Computer Engineering - American Conference on Applied Mathematics, AMERICAN-MATH'11, 5th WSEAS International Conference on Computer Engineering and Applications, CEA'11, 99-104, (2011). Abstract
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Abstract: 3D CAD techniques represent today a crucial tool in almost all the design fields. Nevertheless, due to a number of well known reasons, multi orthographic view drawings are still widely used; accordingly, the conversion of 2D drawings into 3D CAD models (known in the scientific literature as the "reconstruction problem") is still a key issue. During the last decades a number of works, dealing with the reconstruction problem, have been proposed. On the basis of these works, the authors have developed and implemented an automatic procedure that allows the reconstruction of 3D polyhedral models. The reconstruction procedure involves a number of software routines; by means of them, an initial 2D DXF file is processed and a set of 3D solutions, consistent with the initial drawing, is extracted. The obtained 3D models are subsequently output according to the most common 3D exchange formats (e.g. IGES, STEP, Parasolid, etc.). The proposed procedure and its implementation have been developed in order to achieve two main goals: to introduce researchers into the "reconstruction problem" and to create a common basis in order to methodologically compare different procedures dealing with the "reconstruction problem" itself.

Keywords: 3D reconstruction | CAD | Computational geometry | Engineering drawings | Orthographic projections | Pseudo-wireframe

[119] Furferi R., Governi L., Prediction of the spectrophotometric response of a carded fiber composed by different kinds of coloured raw materials: An artificial neural network-based approach, Color Research and Application, 36(3), 179-191, (2011). Abstract
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Abstract: One of the most critical phases of the production of carded fiber is the comparison between the colour of the finished product and the colour desired by a customer or provided in a catalog. In most cases, the required proportions of coloured fibers for obtaining a desired final colour of a fiber are evaluated by trial and error techniques. This approach, which often lacks a computer-aided tool to assist colourists, allows the assessment of a recipe to reproduce a target colour. The companies producing carded fibers often perform a colorimetric control of their product. This is obtained by evaluating the colorimetric distance between the final product, obtained by mixing some coloured raw fibers in order to obtain a homogeneous colour, and the desired one. When this colorimetric distance exceeds a value stated by the customer, the companies have to modify the recipe in order to reduce the gap between the colour of the final product and the desired one. The present work describes a novel approach for a reliable prediction of the spectrophotometric response of a carded fiber based on the spectrophotometric response of the raw materials composing the fiber itself. This is obtained for any variation of an original recipe. The developed system is, first, based on a theoretical approach used for the prediction of reflectance factors obtained by mixing the same kind of differently coloured raw material. A more general approach, based on Artificial Neural Networks (ANNs), is then described. This second approach performs a reliable prediction of the reflectance factors of a carded fiber composed by several kind of differently coloured raw materials. The two approaches were used to predict the reflectance factors of 500 different blends. Colour differences between the predicted reflectance factors and the real spectrophotometric response of the carded fibers are measured and expressed in CIELAB and CMC(2:1) distances under several standard illuminants. Referring to the test performed in the present work, the mean predicted colour difference in terms of CIELAB is less than 0.24. The maximum distance in terms of CMC(2:1) is less than 0.25. Experimental validation demonstrates that the proposed approach is suitable for a reliable, fast and practical prediction of the recipes for carded fibers. For these reasons, the developed system is actually running into the Laboratory of an important textile company located in Prato (Italy): the New Mill S.p.A. © 2010 Wiley Periodicals, Inc.

Keywords: artificial neural network | carded fiber | spectrophotometry

[120] Furferi R., Governi L., Palai M., Volpe Y., Multiple Incident Splines (MISs) algorithm for topological reconstruction of 2D unordered point clouds, International Journal of Mathematics and Computers in Simulation, 5(2), 171-179, (2011). Abstract
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Abstract: An automatic 3D model retrieval from freehand conceptual sketches is a key target for both commercial software houses and academic research. Unfortunately, most of the approaches are not suitable for properly translating stylistic sketches into 3D models. In order to carry out this 3D model conversion, the first task to be dealt with is to turn raster data (3D or 2D free-form curves) into vectorial ones. Such a task represents a key issue which has been addressed by a number of authors but still far to be exhaustively worked out. To address this challenge, this work presents a new method that allows to fit 2D unordered point cloud data with Multiple Incident Splines (MISs). At the heart of the proposed approach are two main procedures: the first one is based on Euclidean Minimum Spanning Tree (EMST) and Principal Component Analysis (PCA) for detecting the main local directions of the point cloud and to order its points while preserving original topology; the second is meant to fit ordered point clouds with spline curves providing a robust intersection and vertex detection. The proposed methodology, tested on a number of case studies, proves to preserve the original topology more efficiently than alternative techniques supplied by commercial vectorization software packages.

Keywords: Curve reconstruction | Freehand sketches | Image Processing | Styling | Unorganized point cloud

[121] Furferi R., Governi L., Volpe Y., Neural network based classification of car seat fabrics, International Journal of Mathematical Models and Methods in Applied Sciences, 5(3), 696-703, (2011). Abstract
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Abstract: Car seat fabrics are uniquely fashioned textiles. A number of them is branded by a sponged-like appearance, characterized by spots and slightly discoloured areas. Their surface anisotropy is considered to be a relevant aesthetic feature since it has a strong impact on customer perceived quality. A first-rate car seat fabric requires a "small" quantity of spots and discoloured areas while fabrics characterized either by a large number or by a low number of spots, are considered to be of lower quality. Therefore, car seat fabric quality grading is a relevant issue to be dealt with downstream to the production line. Nowadays, sponged-like fabric grading is performed by human experts by means of manual inspection and classification; though this manual classification proves to be effective in fabric grading, the process is subjective and its results may vary depending on the operator skills. Accordingly, the definition of a method for the automatic and objective grading of sponged-like fabrics is necessary. The present work aims to provide a computer-based tool capable of classifying sponged-like fabrics, as closely as possible to classifications performed by skilled operators. Such a tool, composed by an appositely devised machine vision system, is capable of extracting a number of numerical parameters characterizing the fabric veins and discoloured areas. Such parameters are, then, used for training an Artificial Neural Network (ANN) with the aim of classifying the fabrics in terms of quality. Finally, a comparison between the ANN-based classification and the one provided by fabric inspectors is performed. The proposed method, tested on a validation set composed by 65 sponged-like fabrics, proves to be able to classify the fabrics into the correct quality class in 93.8% of the cases, with respect to the selection provided by human operators.

Keywords: Artificial neural networks | Car seat fabrics | Grading | Machine vision

[122] Furferi R., Governi L., Palai M., Volpe Y., 3D model retrieval from mechanical drawings analysis, International Journal of Mechanics, 5(2), 91-99, (2011). Abstract
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Abstract: Computer Aided Engineering (CAE) techniques provide effective solutions for automating the whole product development chain process. Designers, engineers, manufacturing professionals and researchers can now leverage solid modeling data and multi-physics analysis in ways that were inconceivable just few years ago. Among CAE techniques, Computer Aided Design (CAD) has been the most effective in providing methodologies capable of compressing product design and manufacturing cycles, assuring faster turnaround time between design and simulation and improving product quality. Designers and manufacture companies reap the rewards of 3D CAD modelling; as a consequence, research is unceasingly stimulated to look forward. On one hand, research aims to improve capabilities of existing CAD methods and tools; on the other hand novel approaches are extensively investigated with the ambition of carrying out innovative CAD techniques capable of lighting sparking design innovation and creativity. This is particularly true for mechanical design: fast and robust 3D retrieval from 2D drawings that was considered future trend few years ago, is now a key target for commercial software houses like Dassault Systems® and Autodesk® as well as a vigorous focus from an academic outlook. Unfortunately, even if a number of works have been carried out during the last decades, these are mainly described by a conceptual point of view. To derive an orderly procedure covering the necessary steps for retrieving 3D models from mechanical drawings could provide a dramatic boost to researchers and practitioners that introduce this issue on their research. Therefore, the main aim of the present work is to carry out a systematic clear and concise step-by-step procedure for 3D retrieval starting from wireframe models. Since the intent is to afford an as clear as possible, guided, procedure for 3D reconstruction, mathematical description is limited to the simplest case of polyhedral objects. The proposed procedures, inspired by state of the art works, can be effectively contribute to speed-up the possible implementation of methodologies confronting the 3D reconstruction problem.

Keywords: 3D Retrieval | Computational geometry | Computer aided design | Mechanical drawings | Pseudo-wireframe

[123] Furferi R., Governi L., Volpe Y., ANN-based method for olive Ripening Index automatic prediction, Journal of Food Engineering, 101(3), 318-328, (2010). Abstract
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Abstract: The influence of ripening degree of drupes during the harvesting period is well established in olive oil sector. A range of methods for expressing the stage of maturity of olives have been proposed in scientific literature. One of the most commonly adopted methods provides the evaluation of a Ripening Index (RI) on the basis of olive skin and pulp colour. Unfortunately, the RI evaluation technique is time-consuming, subjective (depending on expert skill) and depends on environmental conditions that may affect colour appearance of olives. This work describes a novel method for rapid, automatic and objective prediction of the Ripening Index of an olive lot. The method integrates a Machine Vision system, capable of performing a colour-based raw prediction of RI, with an Artificial Neural Network (ANN) based algorithm to refine it. Such a refinement is based on a set of chemical parameters (oil content, sugar content and phenol content) which are provided as input to the ANN and which can be obtained by historical curves for the region where the RI needs to be predicted. Experimental results demonstrate the effectiveness of the proposed approach. © 2010 Elsevier Ltd. All rights reserved.

Keywords: Artificial neural networks | Machine vision system | Ripening index

[124] Carfagni M., Governi L., Meiattini D., Volpe Y., A new methodology for computer aided design of fine porcelain whiteware, 2008 Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, DETC 2008, 3(PART A), 151-158, (2009). Abstract
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Abstract: Fine porcelain products get their peculiar characteristics at the end of their thermal process. During the firing, the product is subjected to shrinkage and a considerable amount of the material mass becomes viscous, causing the product shape to be modified due to the own object weight. As the final object shape is a relevant characteristic for both usability and aesthetics of the commercial product, the activity purpose was to devise a methodology to automatically detect the raw product shape required to match a provided final geometry. Such a methodology has been implemented by means of commercial CAD/FEM tools and should be used in porcelain products design. The research consists of three parts. During the first one an extensive experimental campaign has been carried out in order to model the behavior of the heat treated material; by using the experimental data a numerical model of the material behavior has been built. in the second part the model reliability has been tested by means of a set of FE analysis. Such an analysis simulates the effects of stresses caused by the real industrial firing process. in the end, during the third part, inverse firing process FE simulations have been performed. These simulations will allow the designer to know the raw-product geometry, in order to obtain the expected finished product. .Copyright © 2008 by ASME.

[125] Carfagni M., Governi L., Meiattini D., Volpe Y., A new methodology for computer aided design of fine porcelain whiteware, Proceedings of the ASME Design Engineering Technical Conference, 3(PARTS A AND B), 151-158, (2008). Abstract
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Abstract: Fine porcelain products get their peculiar characteristics at the end of their thermal process. During the firing, the product is subjected to shrinkage and a considerable amount of the material mass becomes viscous, causing the product shape to be modified due to the own object weight. As the final object shape is a relevant characteristic for both usability and aesthetics of the commercial product, the activity purpose was to devise a methodology to automatically detect the raw product shape required to match a provided final geometry. Such a methodology has been implemented by means of commercial CAD/FEM tools and should be used in porcelain products design. The research consists of three parts. During the first one an extensive experimental campaign has been carried out in order to model the behavior of the heat treated material; by using the experimental data a numerical model of the material behavior has been built. In the second part the model reliability has been tested by means of a set of FE analysis. Such an analysis simulates the effects of stresses caused by the real industrial firing process. In the end, during the third part, inverse firing process FE simulations have been performed. These simulations will allow the designer to know the raw-product geometry, in order to obtain the expected finished product. Copyright © 2008 by ASME.

[126] Furferi R., Governi L., The recycling of wool clothes: An artificial neural network colour classification tool, International Journal of Advanced Manufacturing Technology, 37(7-8), 722-731, (2008). Abstract
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Abstract: Recycling of clothes is a straightforward approach for the supply of a coloured raw material which does not involve the cost of the colouring process. A real time and completely automated colour classification tool for woollen clothes to be recycled is proposed. The tool uses the combination of a statistical method, called matrix approach, of a self-organizing feature map (SOFM) and a feed-forward backpropagation artificial neural network (FFBP ANN)-based approach, to correctly classify the clothes by respecting the selection criteria provided by human know-how. The developed tool, which uses an appositely developed workbench with a spectrophotometer, is aware of the way the different coloured clothes to be recycled combine each other to create a new one. The tool has been validated using a set of 5,000 differently coloured clothes to be recycled and the classification error in classifying the clothes is within 5%, i.e., lower than the one resulting from the use of an expert human operator. © 2007 Springer-Verlag London Limited.

Keywords: Colour | Neural networks | Picking | Recycling | Spectrophotometry

[127] Furferi R., Governi L., Machine vision tool for real-time detection of defects on textile raw fabrics, Journal of the Textile Institute, 99(1), 57-66, (2008). Abstract
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Abstract: This work describes an automated artificial vision inspection (AVI) system for real-time detection and classification of defects on textile raw fabrics. The tool (software + hardware) is directly attached to an appositely developed appraisal equipment machine (weave room monitoring system) and the inspection is performed online. The developed tool performs (1) the image acquisition of the raw fabric, (2) the extraction of some critical parameters from the acquired images, (3) an artificial neural network (ANN)-based approach able to detect and classify the most frequently occurring types of defects occurring on the raw fabric and (4) a standard image processing algorithm that allows the measurement of the geometric properties of the detected defects. The reliability of the tool is about 90% (defect detected vs. effectively existing defects), that is, similar to the performance obtained by human experts. Once detected the defects are correctly classified in 88% of cases and their geometrical properties are measured with a sub-pixel precision.

Keywords: Artificial neural network | Image processing | Raw fabrics | Real time

[128] Furferi R., Governi L., Development of an artificial vision inspection system for real-time defect detection and classification on circular knitting machines, WSEAS Transactions on Computers, 5(6), 1186-1193, (2006). Abstract
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Abstract: The present work presents the devising of a new highly automated artificial vision inspection (AVI) tool for real-time defect detection and classification on circular knitting machines. The tool is based on the combination of statistical analysis, Image Processing and an artificial neural network (ANN) approach. The tool (software + hardware) is directly attached to a circular knitting machine and the inspection is performed on-line during other common operations like laser cutting and ironing. The automatic inspection allows the real-time detection and classification of the most frequently occurring types of defects on knitted fabrics, which are significant for purposes of quality control and fabric grading. The reliability of the detection tool, i.e. the ratio between defect detected and effective defects is about 93%. The AVI system has been developed by the Department of Mechanical Engineering, University of Florence (Italy), and the textile research centre Tecnotessile s.r.l. of Prato (Italy).

Keywords: Image processing | Knitting machines | Neural network | Radon transform | Real time | Skewness

[129] Carfagni M., Furferi R., Governi L., A real-time machine-vision system for monitoring the textile raising process, Computers in Industry, 56(8-9), 831-842, (2005). Abstract
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Abstract: This work provides an automatic and non-intrusive tool to objectively monitoring the raising process by measuring the height and the density of the fibres emerging from a raised cloth (pile). These parameters are assessed by a numerical procedure, which elaborates the images provided by an appositely developed machine-vision system. The proposed approach allows the investigation and the control of the raising process and has been validated by experimental measurements performed on a set of specimens (cloths) with several raising degrees. The comparison between the results obtained by the proposed procedure and the ones coming from a widely accepted textile-measuring device (fabric assurance by simple testing, FAST) is also provided. © 2005 Elsevier B.V. All rights reserved.

Keywords: Cloth raising | Image processing | Machine-vision design | Pile density | Pile height

[130] Tucci S., Governi L., Methods of measuring pile density, Tinctoria, 102(4), 43-47, (2005). Abstract
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Abstract: Experimental, analytical and numerical methods of measuring the surface density of the pile of napped fabrics are presented. Surface density of pile is defined as the ratio between the weight of the pile extending above the fabric and the area of the sample to which it belongs. Samples were weighed, shaved and reweighed and the area of the sample was calculated from the number of pixels on a high-resolution image. The density of the fibre removed was estimated as the difference in density of the sample before and after shaving. A non-intrusive analytical method based on the height, diameter and number of pile fibres and a numerical method are described. Calculations based on pure wool and wool blend are presented and compared with the results obtained using the experimental method.

[131] Bartolini F., Carfagni M., Governi L., Model-based extraction of femoral medulla ducts from radiographic images, Image and Vision Computing, 22(3), 173-182, (2004). Abstract
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Abstract: The planning of the hip prosthesis surgical operation is usually performed manually by the surgeon, who 'draws' on a patient's X-ray image the outline of the prosthetic stem in order to choose the one most suitable for the case at hand. In an attempt to give some repeatability and objectivity to the planning phase, a procedure has been devised for hip prosthesis' stem selection based on the extraction of the femoral relevant outlines. This work presents a computer aided method aimed at automatically extracting the medulla duct outlines from a human femur radiographic image. The outlines are retrieved by referring to a suitable geometric model of the generic femoral cross-section; the projection function obtained by simulating the radiographic acquisition of such a model is fitted on the grey-level functions corresponding to the rows of the actual digitised radiographic image by means of a least squares algorithm. The resulting outlines are used in a software tool performing the hip prosthesis pre-operational planning. © 2003 Published by Elsevier B.V.

Keywords: Medical images processing | Model-based image processing | Surgery aiding tools

[132] Carfagni M., Citti P., Governi L., Pierini M., Vibroacoustic optimization of stiffening ribs and damping material distribution on sheet metal parts, Shock and Vibration, 11(3-4), 271-280, (2004). Abstract
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Abstract: Vehicle noise and vibration levels are basic parameters in passenger comfort. Both static and dynamic stiffness of sheet metal parts is commonly increased by means of stiffening ribs. Vibrations are also reduced by adding a layer of damping material on the floor, the roof, the firewall and other parts of the vehicle. In common practice the panels to be treated are ribbed according to criteria based on the designer's experience, rather than on well defined design procedures and are uniformly covered by a layer of damping material. However, these are not efficient design solutions, especially with regard to the effectiveness of vibration reduction and to weight containment. In this paper a novel approach to achieve an optimal distribution of stiffening ribs and damping material will be presented. The proposed method is based on a Genetic Algorithm (G.A.) procedure which takes into account both the vibroacoustic performance and the weight and cost reduction. A simple case study will be illustrated to demonstrate the Capabilities of the developed procedure.

[133] Chiesi F., Governi L., Tolerance analysis with eM-TolMate, Journal of Computing and Information Science in Engineering, 3(1), 100-105, (2003). Abstract
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Abstract: This article presents a review of a commercial computer-aided tolerance analysis tool, eM-TolMate, which is embedded in four major CAD systems (Catia [1], UG [2], Pro/E [3], SDRC [4]). eM-TolMate combines the Monte Carlo statistical simulation techniques with an internal tolerance management system and identifies the key characteristics (i.e. dimensions/clearances of interest) of nominal component models that are critical to proper assembly. Features and tolerances are directly created in CAD models and both single component or multi component analyses are available. For assemblies, eM-TolMate offers the capability to apply user-defined assembling rules or to automatically detect mating conditions. Actual features are varied within the specified tolerance range, and standard or user-defined statistical distributions are used in simulation runs to determine variations of key characteristics. It also offers the capability to rank tolerances based on contribution to the variation, so the user can identify where tolerances need to be tightened or can be loosened. eM-TolMate [5] represents a useful tool in tolerance analysis of mechanical assemblies.

[134] Bandini M., Governi L., Pierini M., Optimal design of damping material distribution in dynamically excited panels, Proceedings of the 2002 International Conference on Noise and Vibration Engineering, ISMA, 441-449, (2002). Abstract
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Abstract: Noise and vibrations levels are basic parameters in passenger comfort. Vibrations are commonly reduced by adding a layer of damping material to the metal sheet of parts of the vehicle body such as the floor, the roof, the firewall. In common practice the panels to be treated are uniformly covered by a layer of damping material; however this is not an efficient design solution especially with regard to the weight containment. In this paper a novel approach to the optimal damping material distribution will be presented. The proposed method is based on a genetic algorithm procedure which takes into account both the vibrational performance and the weight and cost reduction. A simple case study will be illustrated to demonstrate the capabilities of the developed procedure.

[135] Bartolini F., Governi L., Carfagni M., Crispini F., Extracting femoral medulla ducts from radiographic images based on a model of the projection of femur section, IEEE International Conference on Image Processing, 2, (2002). Abstract
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Abstract: This work presents a procedure aimed at automatically extracting the medulla duct outlines from a human femur radiographic image. The outlines are retrieved by referring to a suitable geometric model of the generic femoral cross section; the projection function deriving from such a model is fitted on the grey level values corresponding to the rows of the digitised radiographic image by means of a least square algorithm. The resulting outlines are used in a software system performing the hip prosthesis pre-operational planning.

[136] Carfagni M., Governi L., Pierini M., A genetic algorithm method for optimizing rib arrangements in dynamically excited panels, Proceedings of the 25th International Conference on Noise and Vibration Engineering, ISMA, 37-42, (2000). Abstract
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Abstract: A genetic algorithm has been designed to optimize the arrangement of stiffening ribs that serve to reduce vibrations and noise in dynamically excited panels. The algorithm was tested on the finite element model of a flat panel whose ribs were modeled by raising some of the nodes. The proposed algorithm, validated by comparison with a panel derived from a commercial software package optimization procedure, allows designers to investigate unconventional rib arrangements and evaluate their performance.

[137] Bongini D., Carfagni M., Governi L., Hippin: A semiautomatic computer program for selecting hip prosthesis femoral components, Computer Methods and Programs in Biomedicine, 63(2), 105-115, (2000). Abstract
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Abstract: This work illustrates a computer program designed to aid surgeons in selecting the hip prosthesis femoral component during the preoperation planning stage of hip replacement surgery. Starting from the processing of the patient's coxo-femoral region X-ray image, the program, called Hippin, interacts with the user to outline the femoral region, including the head and the inner contour of the proximal femur. It automatically examines all possible couplings with the patient's femur outlines from a database containing the outlines of the available prostheses created by digitizing the templates normally used in preoperation planning. The resulting images enable the surgeon to visually compare all the alternatives. In addition, the program provides numerical values for the distances between the physiological rotation and prosthesis centers, helping the surgeon in selecting from among the possibilities. The program has been validated by comparing the computer results with actual surgeon selections. (C) 2000 Elsevier Science Ireland Ltd.

Keywords: Hip prosthesis | Image processing | Preoperation planning