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Parotidectomy can affect facial symmetry. Our study evaluated the symmetry of different facial areas and upper neck after total parotidectomy and filling the area with vascularized fat flap (VFF). Facial symmetry was evaluated in eight patients and a control group matched in terms of gender and age, using a three-dimensional (3D) facial scanner. The operated side was compared with the non-operated side and the symmetry compared with that of the control group. Scanning was performed either within the first year (group 1; n = 5) or after 3 years (group 2; n = 3) postoperatively. The patients' cheek and neck areas were found to be significantly more asymmetric, but the cheek area in group 2 was significantly more symmetrical when compared with group 1. VFF appeared to achieve similar facial symmetry to the matched non-operated group. Time had a positive impact on the facial symmetry. The neck area was the most asymmetric, and proved to be unreliable, regardless of whether any procedure was performed or not. [ABSTRACT FROM AUTHOR]

Although personalized polymethylmethacrylate (PMMA) implant production molds for cranioplasty are costly and time-consuming, they allow for better-quality implants. The researchers quantitatively tested the contribution of simplified, low-cost techniques to cosmetic improvement. PMMA prosthesis was placed in a 25-year-old male patient due to osteolysis in the bone flap removed after decompression surgery. A single-sided mold was three-dimensional (3D) printed before the surgery, and the prosthesis was produced during the surgery. In addition, the change in cranial asymmetry was evaluated using a 3D surface scanner after surgery. The mold took half an hour to design and 5 hours to print. The mold cost about 2 dollars. The root means square (RMS) value measured to determine cranial asymmetry decreased from 5.4 mm to 2.8 mm postoperatively. The patient stated that he was pretty satisfied with the cosmetic result. Simple design techniques developed can offer low-cost, fast-design alternative solutions with satisfactory cosmetic results for low-income countries and patients. [ABSTRACT FROM AUTHOR]

Manual removal of burrs on castings introduces health, safety, and environmental concerns. Automated removal of highly variable casting burrs could improve safety, but requires a solution based on robots, smart sensors, and advanced algorithms to tackle the problem in a flexible and cost-effective way. This paper presents a system for automatic tool trajectory generation for robotic deburring of cast parts with a specific focus on the robotic tool trajectory generation algorithm. The system generates a robotic trajectory adapted to the specific workpiece based on CAD model and 3D scans of the workpiece. The registered 3D scans and CAD model is used to generate a 3D model of each individual workpiece. This is fed into the tool trajectory generation algorithm. The algorithm uses the generated 3D model as well as a priori knowledge of the casting process to generate the tool trajectory. The tool trajectory planning algorithm has been tested on a set of various 3D models of cast parts, and the generated robotic tool path has been both simulated and tested on a KUKA KR 60. [ABSTRACT FROM AUTHOR]

Lightweight porous composites have been widely explored to improve their acoustic and thermal performances. Hempcrete can serve as thermal insulating or soundproofing material by utilising its high porosity. However, the rigorous correlation between hempcrete thermal and acoustic performance and its pore structure remains poorly understood due to its different pore types. In this study, three hempcrete pore types [i.e., i) inter-pore between hemp and mortar, ii) hemp intra-pore, and iii) mortar intra-pore] were modified by tamping, delignification, and foaming agent conditions, respectively. Then the volumes of three types of pores were estimated using X-ray micro-computed tomography (μCT) and mercury intrusion porosimetry. The new segmentation methods were developed and their reliability and accuracy were validated. Then, the pore volumes were correlated to the thermal and acoustic properties of hempcrete. Low tamping and high delignification conditions are recommended to increase inter-pore volume and enhance hempcrete performances relating to both thermal insulation and sound absorption for real-world hempcrete applications. [ABSTRACT FROM AUTHOR]

Real-time inspection of large mechanical parts manufacturing using camera-based scanning systems are increasingly adopted in industry 4.0. It leads to take preventive actions during the manufacturing process and then to fabricate mechanical parts right-first-time with respect to specified tolerances. Therefore, the use of camera-based scanners requests a preliminary calibration process. It consists on estimating the intrinsic and extrinsic parameters required to relate the 3D world point to its projection on the image plane. Since selection of the calibration grid poses affect the calibration quality, one approach-based machine learning (ML-approach) is proposed including the polynomial approximation of the reprojection errors function of 6 degree of freedom (DoF) combined with particle swarm optimization (PSO). Synthetic and experimental evaluations have been performed while assessing the performance of the proposed ML-approach. The synthetic evaluation reveals a better convergence of the intrinsic and extrinsic parameters in comparison to recent published calibration methods by Wizard (CW-method) and Rojtberg (R-method). The experimental evaluation of the ML-approach shows an average error R E < 12 µm and a sub-micrometre repeatability, which confirm the benefit of using machine vision-based scanning systems for the inspection of large volume parts in real time. [ABSTRACT FROM AUTHOR]

• Vision-based 3D scanning techniques, • Determining measurement uncertainty and acceptance level, • Examination of large-surface objects with rough surfaces, • Application of numerical analysis and engineering inspection, • Laboratory tests of External Thermal Insulation Composite Systems (ETICS) Measuring the deformation of large-area objects with non-uniform rough textures using traditional techniques is technically challenging and time-consuming. This article presents a comprehensive solution that enables the precise measurement of the deformation of large-area elements of external thermal insulation composite systems (ETICS). The laboratory tests for environmental resistance were conducted in a climatic chamber. The surface of the wall underwent irregular deformation owing to thermal and humidity cycles. The deformation state at different stages of exposure was recorded using 3D scanning techniques. Scanning results were paired using a simplified cause-effect graph, and the deformation was measured by engineering inspection. Evaluation criteria were developed using measurement uncertainty and a straightforward binary acceptance principle. Finally, compliance tests were performed to confirm the reproducibility and repeatability of the method. [ABSTRACT FROM AUTHOR]

• An improved DeepLabV3+ network (IDeepLabV3+) for PWS lesion segmentation was developed based on the classic DeepLabV3+ architecture. • The deep learning-based semantic segmentation method can automatically segment PWS lesion of different color and shape in texture mapping of 3D images. • Semantic segmentation can be used together with 3D scan for the evaluation of area of facial PWS lesions. Portwine stain (PWS) birthmarks are congenital vascular malformations. The quantification of PWS area is an important step in lesion classification and treatment evaluation. The aim of this study was to evaluate the combination of 3D scan with deep learning for automated PWS area quantization. PWS color was measured using a portable spectrophotometer. PWS patches (29.26–45.82 cm2) of different color and shape were generated for 2D and 3D PWS model. 3D images were acquired by a handheld 3D scanner to create texture maps. For semantic segmentation, an improved DeepLabV3+ network was developed for PWS lesion extraction from texture mapping of 3D images. In order to achieve accurate extraction of lesion regions, the convolutional block attention module (CBAM) and DENSE were introduced and the network was trained under Ranger optimizer. The performance of different backbone networks for PWS lesion extraction were also compared. IDeepLabV3+ (Xception) showed the best results in PWS lesion extraction and area quantification. Its mean Intersection over Union (MIou) was 0.9797, Mean Pixel Accuracy (MPA) 0.9908, Accuracy 0.9989, Recall 0.9886 and F1-score 0.9897, respectively. In PWS area quantization, the mean value of the area error rate of this scheme was 2.61 ± 2.33. The new 3D method developed in this study was able to achieve accurate quantification of PWS lesion area and has potentials for clinical applications. PWS patches of different color and shape were use to create 2D and 3D models. 3D images were acquired by 3D scanner to create corresponding texture maps. Deep learning automatic segmentation using different backbone networks was used to extract PWS lesion from texture mapping of 3D images. [Display omitted] [ABSTRACT FROM AUTHOR]

Cranioplasty and modulation of frontoorbital advancement (FOA) in children with craniosynostosis aims to achieve an attractive aesthetic and functional rehabilitation of the forehead area, comparable to that in unaffected children. Based on a three-dimensional surface scan, a cephalometric data evaluation with new parameters for the quantification of physiological and pathological cranial morphologies, and objective evaluation of postoperative follow-up in comparison to an age-equivalent standard population, were performed. In a prospective study, 80 children were operated on with non-syndromic craniosynostosis (trigonocephalus, n = 30; plagiocephalus, n = 10; scaphocephalus, n = 38; brachycephalus, n = 2) and pre- and 3, 6, 12, 18 and 30 months postoperative three-dimensional surface scans were obtained (3DShape, Erlangen, Germany) and morphometrically measured (Onyx Ceph, Image Instruments, Chemnitz, Germany). In addition, 49 healthy children who were not operated on were measured at equivalent ages (n = 25 [6 months]; n = 20 [9 months]; n = 4 [12 months]). All patient groups showed stable long-term results with regard to shaping of the forehead. Cranioplasty in patients with scaphocephalus resulted in a significant widening of the anterior (73.9 ± 3.5 mm; p < 0.001) and posterior (132.2 ± 5.2 mm; p < 0.001) cranial width, with no significant difference from the norm population 1 year after surgery (p = 0.6597). As parameters for the correction of trigonocephaly, the frontal angle showed significant improvement (145.9 ± 3.7°; p < 0.001). While the parietal angle 12 months after surgery showed similar values as the norm population, the frontal angle was about 10° smaller than in healthy children (p = 0.0055), despite a clinically inconspicuous physiognomy. As part of the correction of plagiocephaly, the patients tended to relapse in the postoperative course, although there was no statistically significant difference in the frontal angle compared to that in the norm population (153.3 ± 3.9°; p = 0.06). While 6 months after surgery all patients showed a normal cranial volume development compared to healthy children of the same age, the volumes of brachycephalic patients remained below the norm (1244.2 ± 153.2 cm3; p = 0.0244). Overall, the analysis of the norm population showed a growing dispersion of measurement values with increasing age, which was observed to be more concentrated in the operated cranial morphologies. The determination of new pathology-specific morphometric parameters on the three-dimensional surface scan enables an objective quantification of physiological and pathological cranial morphologies of children. A comparison of operated children with a healthy, age-appropriate comparison group showed that preoperative and statistically significant deviations of the new measuring parameters in long-term follow-up could be normalized through surgical intervention, although this does not apply without limitations to children with coronary suture synostosis. [ABSTRACT FROM AUTHOR]

Purpose Depending on the site and size of head and neck cancer, the disease affects patients' appearance and subsequently their quality of life. The aim of this study was to correlate subjective and objective evaluation of facial appearance and associated quality of life following ablative tumor surgery and microsurgical reconstruction. Material and methods A total of 99 patients with combined ablative and reconstructive microsurgical procedure for head and neck malignancy and seven patients with non-malignant disease were examined by three-dimensional (3D) (photogrammetry at least 6 months post-surgery and were evaluated by two-dimensional (2D) and 3D means for symmetry and facial proportions. Measurements were correlated with subjective reporting from the University of Washington Quality of Life Questionnaire and observer ratings. Results Of the 106 patients, three patients scored themselves as significantly disfigured (2.8%), 19 were bothered by their appearance (17.9%), 27 (25.5%) reported no change, and 57 (53.8%) reported minor changes in their appearance. On 2D evaluation, 10 patients (9.4%) showed severely abnormal facial proportions. On 3D analysis, 17 patients showed major asymmetry. There was a high correlation (0.67) between patient and observer subjective rating (p < 0.05). While 2D evaluation alone showed no significant correlation with subjective rating, 3D evaluation showed a moderate correlation (0.37; p < 0.05). The best results were achieved by combining 2D and 3D measurements (0.5; p < 0.05). Young female patients were most critical about their appearance. Conclusion Following combined ablative and microsurgical reconstructive procedures, patients have a realistic perception of their appearance compared with observer ratings and a combination of 2D and 3D objective evaluation. [ABSTRACT FROM AUTHOR]

Double corrugated profiles made of thin sheet metal are susceptible to loss of local stability and their shapes exclude the possibility of applying design standards. Arch structures made of these profiles can have a different state of combined axial force and bending moment. Previous scientific research allowed the identification of the load carrying capacity and stability only for selected axial force parameters. The article presents the distribution of the interaction between the bending moment and the axial force, allowing the evaluation of the load-carrying capacity within the entire for static forces. Limit curves were developed using parametrised non-linear numerical analyses. Ansys software and the digital copy of the test model were used for the analysis. Limit curves were generated for two grades of steel and six thicknesses of sheet metal. In addition to the envelope, the limits for the elastic range, the pre-buckling elastoplastic range, and the post-buckling plastic range were estimated. The results are summarised in diagrams and tables. • Axial force and bending moment interaction • Finite element mesh verification and optimization • 3D scanning and reverse engineering • Geometrically and Materially Non-linear Analysis • Nonlinear advanced numerical analysis ANSYS software [ABSTRACT FROM AUTHOR]

Objective Frontoorbital advancement (FOA) in patients with non-syndromic craniosynostosis mainly addresses the aesthetic and functional correction of the frontoorbital region. To help define the operative strategy and any follow-up assessments after surgical correction, objective parameters describing the critical regions of skull deformity are essential. Based on 3D morphometric analysis, new parameters for the documentation of changes of the frontoorbital bandeau were developed in a prospective study. Methods and materials In a prospective series, 13 children with non-syndromic craniosynostosis (seven metopic, four unilateral coronal, and two bilateral coronal) treated with frontoorbital advancement, underwent detailed morphometric and volumetric evaluation using a 3D light optical scan system (3D-Shape, Erlangen, Germany). Measurements were obtained preoperatively and at 3, 6 and 12 months postoperatively with newly developed parameters generated by cephalometric analysis software (Onyx Ceph, Image Instruments, Chemnitz, Germany). Results In most patients, frontoorbital advancement resulted in stable long-term results without growth inhibition and with normalization or improvement of ongoing skull development. The mean frontal angle was 145° and the frontoparietal angle 137–140°. The cephalic index was normalized or markedly improved. Head circumference and head height increased significantly ( p = 0.001 and p = 0.002, respectively). These changes were confirmed in all postoperative measurements. Conclusion During the 12-month follow-up period all angle parameters proved to be stable and no major impairment of normal skull growth was observed after FOA. The frontoorbital angle is a useful parameter in evaluating long-term outcome. The frontoparietal angle is important for the stability of the frontoparietal region, in which a certain growth inhibition may be observed postoperatively. [ABSTRACT FROM AUTHOR]

In order for bicycle helmets to maintain sufficient coverage and protection of riders, the helmets must be adequately positioned and secured on the head. This research investigates helmet's dynamic stability parameters in order to determine whether a customised liner can improve the retention and therefore safety. A specialist 3D scanner was used to scan a total of 17 male participants who volunteered for this study. Through 3D scanning the shape and depth of each section of a participant's head and facial structure was captured. All the heads scanned were orientated with respect to the same co-ordinates based on the Australian and New Zealand Standards in order to customize the liner design to fit the user's heads. The dynamic stability of the commercially available helmets and the customized helmet were assessed using relevant video and goniometer techniques. The results indicate that for frontal roll-off, the customised helmet liner passed in all simulations of the 160 mm drop height. It consistently performed better in the lateral roll-off at height of 40 mm and 80 mm compared with the commercially available helmets. While the dynamic stability measurements and the design strategies offer the potential to improve fit for different user's head, further studies should take into consideration a larger population size to draw more accurate conclusions. [ABSTRACT FROM AUTHOR]

Firefighters have reported their protective boots to be bulky and ill-fitting, which they believe restrict the lower body movement on the unpredictable fireground. This study used 3D foot scanning to compare the shape of firefighters' feet to the general population, the shape of female firefighters' feet to males, and the impact of the heavy fire gear on foot shape. The results found the foot breadth of firefighters was larger than the general population and the feet of female firefighters were slimmer than males. Furthermore, it revealed that the feet of firefighters became longer, wider, and flatter when bearing the weight of fire gear. Protective boots should be designed based on the foot shape and dimensions of the actual population, with consideration of sex differences and the impact of weight-bearing for their safety. [ABSTRACT FROM AUTHOR]

Increasing competitive pressure within industries producing long-living, cost intensive products drive the need to optimize product life cycles in terms of faster time to market, sustainable operation, reengineering and recycling. In this context, complexity of IT systems is growing and has to connect different life cycle phases. Especially new concepts of Product Service Systems (PSS) lead to a connection between product design, maintenance, repair and overhaul (MRO). There are still many challenges concerning interface problems between different IT-Systems. They are caused by different data formats, continuous demand for information or integration of new technologies. Thus, Life Cycle Engineering (LCE) has gained an important role and needs to consider integration of new industry 4.0 solutions like cloud services, big data or cyber physical systems. This paper gives an overview about these challenges, future development and new research approaches. A deeper view is taken at one promising approach in the field of maintenance of Printed Circuit Boards (PCB). This approach is about invention and implementation of a new process that combines both electrical and optical measuring techniques to automate circuit and layout plan reconstruction of long-living and cost intensive electronic boards. [ABSTRACT FROM AUTHOR]

Purpose Arthroscopic repair of superior labral anterior to posterior (SLAP) lesions is often associated with a prolonged period of pain during the rehabilitation process. This might possibly be due to hypoxia in the biceps tendon anchor caused by sutures. The purpose of the study was to investigate the arterial supply of the long head of the biceps brachii tendon (LHBT) that may be impaired by surgery in the region of the biceps tendon anchor. Methods On 20 human formalin-fixed bodies, the anterior circumflex humeral artery (ACHA) was located and followed into the intertubercular groove until it reached the LHBT. On 10 fresh-frozen anatomic specimens of the upper extremities, contrast medium was injected into the axillary artery, a 3D scan was performed, and multiplanar reconstructed (MPR) slices were generated. A set of maximum intensity projection (MIP) reconstructions from 10 computed tomography angiographies (CTA) of the upper extremities was used to confirm the findings of the 3D scan. Results All anatomical dissections and radiological investigations revealed that the proximal portion of the LHBT was consistently supplied by an ascending branch of the ACHA. No artery was found to supply the biceps tendon anchor from the proximal aspect. Conclusions As the arterial supply of the LHBT is mainly provided by the ACHA, which enters the glenohumeral joint from the distal aspect, surgery at the bony origin of the LHBT may not interfere with this specific vessel. [ABSTRACT FROM AUTHOR]

Abstract: The objective of this study was to quantify head-and-face shape variations of U.S. civilian workers using modern methods of shape analysis. The purpose of this study was based on previously highlighted changes in U.S. civilian worker head-and-face shape over the last few decades – touting the need for new and better fitting respirators – as well as the study's usefulness in designing more effective personal protective equipment (PPE) – specifically in the field of respirator design. The raw scan three-dimensional (3D) data for 1169 subjects were parameterized using geometry processing techniques. This process allowed the individual scans to be put in correspondence with each other in such a way that statistical shape analysis could be performed on a dense set of 3D points. This process also cleaned up the original scan data such that the noise was reduced and holes were filled in. The next step, statistical analysis of the variability of the head-and-face shape in the 3D database, was conducted using Principal Component Analysis (PCA) techniques. Through these analyses, it was shown that the space of the head-and-face shape was spanned by a small number of basis vectors. Less than 50 components explained more than 90% of the variability. Furthermore, the main mode of variations could be visualized through animating the shape changes along the PCA axes with computer software in executable form for Windows XP. The results from this study in turn could feed back into respirator design to achieve safer, more efficient product style and sizing. Future study is needed to determine the overall utility of the point cloud-based approach for the quantification of facial morphology variation and its relationship to respirator performance. [Copyright &y& Elsevier]

Abstract: Objectives: To evaluate the proximal contact on class II composite restorations constructed using various restorative approaches by a morphological analysis. Methods: Sixty plastic premolar teeth were prepared for class II cavities. These teeth were divided into six groups and restored using different materials and matrix systems. Two composite materials used were a microhybrid composite Filtek Z100 (3M/ESPE) and a packable composite P60 (3M/ESPE). Three interproximal matrix systems were two circumferential metal matrices (0.05mm and 0.03mm thin, respectively) combined with a Tofflemire retainer, and a pre-contoured sectional matrix system (Palodent). The contact morphologies of the restorations were visually inspected with regard to their buccolinugal and mesiodistal aspects. The contact tightness was measured by inserting different amounts of metal strips. For quantitatively morphologic analysis, three-dimensional (3D) scans of proximal contacts were performed. The results were analysed with two-way ANOVA and the Tukey test. Results: Under visual observation, contact surfaces in sectional matrix groups showed anatomic profile but concave in the centre, whilst the circumferential matrix groups showed flat profiles. The sectional matrix improved the contact tightness. The 3D analysis revealed that the matrix system was correlated with the contact morphology, since the sectional matrix generated significantly deeper and wider surface concavity. Conclusions: All the interproximal matrix systems presented some deficiency in either the contact tightness or contours. Although the sectional matrix system enhanced contact tightness, it caused contact concavity by formation of interproximal marginal overhang. The quantitative morphologic analysis helps to examine improper proximal contact and the associated problems. [Copyright &y& Elsevier]

• Constitutive law for the prediction of stress–strain response of corroded strands. • Investigated effects of corrosion on the decay of mechanical properties of strands. • Useful correlation between maximum pit depth and cross-sectional loss of a wire. • Critical cross-sectional loss values for corroded prestressing strands. • Database on available results on corroded prestressing strands. The paper presents an experimental and analytical study on the tensile behaviour of naturally corroded prestressing strands. A total of twenty-four strands were extracted from full-scale beams which were exposed during 10 years to chlorides from sea water. Firstly, a database has been created on the dependency of the maximum pit depth on the strand mass loss or on the section loss of the most corroded wire. Secondly, the morphology of corrosion pits and the maximum cross-sectional loss of each external wire have been measured. Finally, based on conducted tensile tests, a new constitutive law (CPS-model) is proposed to predict the mechanical behaviour of prestressing strands induced by pitting corrosion. [ABSTRACT FROM AUTHOR]

Abstract: Garment fit and resultant air volume is a crucial factor in thermal insulation, and yet, it has been difficult to quantify the air volume of clothing microclimate and relate it to the thermal insulation value just using the information on the size of clothing pattern without actual 3D volume measurement in wear condition. As earlier methods for the computation of air volume in clothing microclimate, vacuum over suit and circumference model have been used. However, these methods have inevitable disadvantages in terms of cost or accuracy due to the limitations of measurement equipments. In this paper, the phase-shifting moiré topography was introduced as one of the 3D scanning tools to measure the air volume of clothing microclimate quantitatively. The purpose of this research is to adopt a non-contact image scanning technology, phase-shifting moiré topography, to ascertain relationship between air volume and insulation value of layered clothing systems in wear situations where the 2D fabric creates new conditions in 3D spaces. The insulation of vests over shirts as a layered clothing system was measured with a thermal manikin in the environmental condition of 20°C, 65% RH and air velocity of 0.79m/s. As the pattern size increased, the insulation of the clothing system was increased. But beyond a certain limit, the insulation started to decrease due to convection and ventilation, which is more apparent when only the vest was worn over the torso of manikin. The relationship between clothing air volume and insulation was difficult to predict with a single vest due to the extreme openings which induced active ventilation. But when the vest was worn over the shirt, the effects of thickness of the fabrics on insulations were less pronounced compared with that of air volume. In conclusion, phase-shifting moiré topography was one of the efficient and accurate ways of quantifying air volume and its distribution across the clothing microclimate. It is also noted that air volume becomes more crucial factor in predicting thermal insulation when clothing is layered. [Copyright &y& Elsevier]

Summary: Quantification of the complex breast region can be helpful in breast surgery, which is shaped by subjective influences. However, there is no generally recognized method for breast volume calculation. Three-dimensional (3D) body surface imaging represents a new alternative for breast volume computation. The aim of this work was to compare breast volume calculation with 3D scanning and three classic methods, focusing on relative advantages, disadvantages, and reproducibility. Repeated breast volume calculations of both breasts in six patients (n=12) were performed using a 3D laser scanner, nuclear magnetic resonance imaging (MRI), thermoplastic castings, and anthropomorphic measurements. Mean volumes (cc) and mean measurement deviations were calculated, and regression analyses were performed. MRI showed the highest measurement precision, with a mean deviation (expressed as a percentage of mean breast volume) of 1.56±0.52% compared with 2.27±0.99% for the 3D scanner, 7.97±3.53% for thermoplastic castings, and 6.26±1.56% for the anthropomorphic measurements. Breast volume calculations using MRI showed the best agreement with 3D scanning measurement (r=0.990), followed by anthropomorphic measurement (r=0.947), and thermoplastic castings (r=0.727). Compared with three classical methods of breast volume calculation, 3D scanning provides acceptable accuracy for breast volume measurements, better spatial interpretation of the anatomical area to be operated on (due to lack of chest deformation), non-invasiveness, and good patient tolerance. After this preliminary study and further development, we believe that 3D body surface scanning could provide better preoperative planning and postoperative control in everyday clinical practice. [Copyright &y& Elsevier]

Modeling the shape of the scalp and face is essential for the design of protective helmets and other head-borne equipment. However, head anthropometry studies using optical scanning rarely capture scalp shape because of hair interference. Data on scalp shape is available from bald men, but female data are generally not available. To address this issue, scalp shape was digitized in an ethnically diverse sample of 100 adult women, age 18-59, under a protocol that included whole head surface scanning and scalp measurement using a three-dimensional (3D) coordinate digitizer. A combined male and female sample was created by adding 3D surface scans of a similarly diverse sample of 80 bald men. A statistical head shape model was created by standardizing the head scan data. A total of 58 anatomical head landmarks and 12 head dimensions were obtained from each scan and processed along with the scans. A parametric model accounting for the variability of the head shape under the hair as a function of selected head dimensions was developed. The full-variable model has a mean shape error of 3.8 mm; the 95th percentile error was 7.4 mm, which were measured at the vertices. The model will be particularly useful for generating a series of representing a target population as well as for generating subject-specific head shapes along with predicted landmarks and dimensions. The model is publicly available online at http://humanshape.org/head/. [ABSTRACT FROM AUTHOR]

• A 3D parametric model of human calves was proposed and verified. • The parametric model was found effective to reduce the data complexity of all calves in database to only the 1st order principal component. • With the model, methodological framework of fast reconstructing representative human calves for individual patients was proposed. • A smart morphing leg mannequins were manufactured based on the model to evaluate pressure distributions or design customized compression stockings for individual patients. Accurate dose of compression imposed by functional compression garments, such as medical compression stockings, is critical for medical treatment or rehabilitation. To evaluate or provide fitted compression stockings for individuals, the real curved calf shapes other than just anthropometric parameters are required. This paper proposes and verifies a simple 3D parametric model of human calf that can fast and efficiently construct representative calves for evaluation or size-design purposes. Instead of selecting feature points, shape parameters were used to characterize the real calves. Based on principal component analysis and a database of 220 scanned Chinese subjects, the proposed parametric model was found as capable of largely reducing the data complexity to only the 1st order principal component with a major variance percentage of as high as 96%. A methodological framework of parametric modeling was then proposed. Results show that the proposed parametric model and method can fast produce valid representative shapes of patients' calves, with which commercial stockings can be evaluated and customized stockings can be designed. It can be concluded that the proposed parametric model and method can highly boost evaluation/size customization of MCSs, and will also inspire the research on customization of other compression garments. [ABSTRACT FROM AUTHOR]

This paper proposed a novel methodology to determine the angle of repose (AoR) of various biomass materials. Because of irregular shape and varying particle size distribution, slopes of biomass materials are uneven frequently and the two traditional measurement methods of AoR are therefore less applicable and reliable. In general, only partial slopes of heap surface are selected to measure AoR, although a representable slope is barely defined in standard methods. In this case, the subjective selection of slopes may result in significant deviations. Hence, we presented an efficient and reliable measurement method of AoR. In addition to the traditional bottomless cylinder test, the new technology, 3D scan, was used to digitize the generated bulk heap. Then, two data processing methods were introduced to deal with different heap forms: direct calculation based on the linear least-squares regression with regard to the whole heap surface and the pre-selection of planes for excluding outliners caused by particle bridging. For the purpose of simplifying the process, a self-developed graphic user interface (GUI) was used to analyze four kinds of biomass fuels, namely, olive stone, almond shells, forest residues and willow chips, and verify the proposed method. Both methods significantly decreased the deviations of results without increasing operating time and cost. • The first study to obtain angle of repose of biomasses efficiently by applying 3D scan with fewer individual interpretations. • Tests of four kinds of representative and widely available biomasses were used to verify the applicability of both methods. • Uneven slopes of biomass' cone are taken into consideration and the angle of repose is therefore more precise. • The methodology provides a possibility to reach valid result of material model calibration with lower measurement deviation. [ABSTRACT FROM AUTHOR]

• We tested a 3D scanner as an affordable and fast electrode digitizer. • The accuracy of the 3D scanned electrode positions is higher than template positions. • EEG source models improve with 3D scanned electrode positions. In this study, we evaluated the use of a structured-light 3D scanner for EEG electrode digitization. We tested its accuracy, robustness and evaluated its practical feasibility. Furthermore, we assessed how 3D scanning of EEG electrode positions affects the accuracy of EEG volume conduction models and source localization. To assess the improvement in electrode positions and source results, we compared the electrode positions both at the scalp level and by quantifying source model accuracy between the 3D scanner, generic template, and cap-specific electrode positions. The use of the 3D scanner significantly improves the accuracy of EEG electrode positions to a median error of 9.4 mm and maximal error of 32.8 mm, relative to the custom (median error of 10.9 mm, maximal error 39.1 mm) and manufacturer's template positions (median error of 13.8 mm, maximal error 57.0 mm). The relative difference measure (RDM) of the EEG source model averaged over the brain improves from 0.18 to 0.11. The dipole localization error averaged over the brain improves from 11.4 mm to 7.0 mm. A structured-light 3D scanner improves the electrode position accuracy and thereby the EEG source model accuracy. It is more affordable than systems currently used for this, and allows for robust and fast digitization. Therefore, we consider it a cost and time-efficient way to improve EEG source reconstruction. [ABSTRACT FROM AUTHOR]