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ObjectivesStroke patients suffer from ankle joint deformities due to spastic ankle muscles. This study evaluated the viability of using 3D scanned surface images of the feet of stroke victims to visually assess the deformities of a hemiparetic foot and investigated the influences of deformed ankle joints on gait kinematics.MethodsA total of 30 subjects with stroke-induced hemiparesis and 11 age-matched healthy controls completed the clinical assessments. We analyzed their feet's morphometric characteristics using a 3D scanner, identified convenient anthropometric measurements, and conducted gait trials on even and uneven terrains. The 3D foot morphometric characteristics were evaluated using the geometric morphometrics method (GMM).ResultsResults showed that there were significant differences in bilateral foot shapes between the chronic stroke patients and healthy controls and between the paretic and non-paretic sides in the chronic stroke patients. In stroke patients, those with the smaller medial malleoli's vertical tilt angles showed significantly different ankle ranges of motion of dorsi-/plantar flexion during gaits on uneven terrains (p = 0.009). In addition, those with the greater medial malleoli's vertical tilt angles showed significantly different ankle ranges of motion of inversion/eversion during gaits on even and uneven terrains (p < 0.05).ConclusionUsing 3D scanning technology, bilateral morphometric changes in the feet of chronic stroke patients were shown by GMM and the simple anthropometric measurements identified its shape deformities in the feet. Their possible effects on gait kinematics while walking on uneven terrains were investigated. Current methodology can be potentially useful in applying conventional productions of clinically manufactured, patient-fitted ankle-foot-orthosis in orthotics and prosthetics, and in detecting various unidentified pathological deformities in the feet.

The foot is a vital organ, as it stabilizes the impact forces between the human skeletal system and the ground. Hence, precise foot dimensions are essential not only for custom footwear design, but also for the clinical treatment of foot health. Most existing research on measuring foot dimensions depends on a heavy setup environment, which is costly and ineffective for daily use. In addition, there are several smartphone applications online, but they are not suitable for measuring the exact foot shape for custom footwear, both in clinical practice and public use. In this study, we designed and implemented computer-vision-based smartphone application OptiFit that provides the functionality to automatically measure the four essential dimensions (length, width, arch height, and instep girth) of a human foot from images and 3D scans. We present an instep girth measurement algorithm, and we used a pixel per metric algorithm for measurement; these algorithms were accordingly integrated with the application. Afterwards, we evaluated our application using 19 medical-grade silicon foot models (12 males and 7 females) from different age groups. Our experimental evaluation shows that OptiFit could measure the length, width, arch height, and instep girth with an accuracy of 95.23%, 96.54%, 89.14%, and 99.52%, respectively. A two-tailed paired t-test was conducted, and only the instep girth dimension showed a significant discrepancy between the manual measurement (MM) and the application-based measurement (AM). We developed a linear regression model to adjust the error. Further, we performed comparative analysis demonstrating that there were no significant errors between MM and AM, and the application offers satisfactory performance as a foot-measuring application. Unlike other applications, the iOS application we developed, OptiFit, fulfils the requirements to automatically measure the exact foot dimensions for individually fitted footwear. Therefore, the application can facilitate proper foot measurement and enhance awareness to prevent foot-related problems caused by inappropriate footwear. [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]

Methods of digital human modeling have been developed and utilized to reflect human shape features. However, most of published works focused on dynamic visualization or fashion design, instead of high-accuracy modeling, which was strongly demanded by medical or rehabilitation scenarios. Prior to a high-accuracy modeling of human legs based on non-uniform rational B-splines (NURBS), the method of extracting the required quasi-grid network of feature points for human legs is presented in this work. Given the 3D scanned human body, the leg is firstly segmented and put in standardized position. Then re-sampling of the leg is conducted via a set of equidistant cross sections. Through analysis of leg circumferences and circumferential curvature, the characteristic sections of the leg as well as the characteristic points on the sections are then identified according to the human anatomy and shape features. The obtained collection can be arranged to form a grid of data points for knots calculation and high-accuracy shape reconstruction in future work. [ABSTRACT FROM AUTHOR]

Objective: Three-dimensional assessment of nasal morphology in patients with unilateral cleft lip nose treated by cartilage graft augmentation. Design: Retrospective study. Patients and Intervention: Thirteen patients with unilateral cleft lip nose underwent definitive secondary rhinoplasty and postsurgical changes were examined using a three-dimensional (3D) laser scan. Main Outcome Measure: Nasal dorsum length, nasal tip, alar width, and alar base width in frontal view; nasion depth, nasal tip projection, nasal dorsal angle, and nasal tip angle in lateral view; nostril width, nostril height, and nasal tip height in basal view were measured at preoperative (T1: within 6 months), short follow-up (T2: 2-10 weeks), and long follow-up (T3: 9-14 months). Results: A significant change in alar width, alar base width, nostril width, and nostril height at the cleft side, nasal dorsum length, nasion depth, nasal tip projection, and nasal tip height was observed from T1 to T3 follow-up after rhinoplasty (P <.05), whereas the nostril height at the noncleft side was also significantly increased at T2 follow-up but the mean change in height relapsed at T3 follow-up. Alar width, alar base width, and nostril width at the noncleft side, and nasal tip angle did not change significantly after surgery at any follow-up period. Conclusions: 3D imaging evaluation after secondary cleft rhinoplasty demonstrated improved functional and aesthetic outcomes using a septal or conchal graft. [ABSTRACT FROM AUTHOR]

This study demonstrates a cost-effective portable fabrication system for 3D printing complex structures from polydimethylsiloxane (PDMS). Material development and characterisation allowed for the design and production of a 3D printer that is capable of fabricating PDMS structures using a photo-initiator and a LED curing process. A 3D model of a participant's ear was captured using a handheld scanner. These data were used to directly 3D print an ear. Micro-extrusion direct deposition of PDMS at room temperature is demonstrated via a custom designed 3D printer, with in situ UV cross-linking to facilitate curing of the PDMS during the 3D printing process. This 3D printer has great potential to be used as a fast and facile fabrication approach to create facial and other prosthesis. Future developments will also focus on other application areas such as microfluidics, flexible electronics, and other biomedical applications. [ABSTRACT FROM AUTHOR]

While three-dimensional measurement technology is spreading fast, its meaningful application to sedimentary geology still lacks content. Classical shape descriptors (such as axis ratios, circularity of projection) were not inherently three-dimensional, because no such technology existed. Recently a new class of three-dimensional descriptors, collectively referred to as mechanical descriptors, has been introduced and applied for a broad range of sedimentary particles. First-order mechanical descriptors (registered for each pebble as a pair {S, U} of integers), refer to the respective numbers of stable and unstable static equilibria and can be reliably detected by hand experiments. However, they have limited ability of distinction, as the majority of coastal pebbles fall into primary class { S , U } = { 2 , 2 } . Higher-order mechanical descriptors offer a more refined distinction. However, for the extraction of these descriptors (registered as graphs for each pebble), hand measurements are not an option and even computer-based extraction from 3D scans offers a formidable challenge. Here we not only describe and implement an algorithm to perform this task, but also apply it to a collection of 271 pebbles with various lithologies, illustrating that the application of higher-order descriptors is a viable option for geologists. We also show that the so-far uncharted connection between the two known secondary descriptors, the so-called Morse–Smale graph and the Reeb-graph, can be established via a third order descriptor which we call the master graph. [ABSTRACT FROM AUTHOR]

Cohesion and friction angle are important indicators of shear strength in mining engineering. Indoor testing methods are detached from the actual state of the rock mass and affected by disturbances and significant dimensional effects that do not fully reflect the shear strength of the rock mass itself. In situ borehole shear testing is of great practical importance because of its low disturbance and high speed. In this paper, a new testing device based on the principle of a rock borehole shear tester was designed to simulate the shear test in the laboratory. Seven shear indenters were designed to test the effect of different tooth heights, spacing, and angles on the shear strength of rock-like specimens, and the damage surface was scanned in three dimensions and compared with conventional triaxial tests and compression shear tests. The results show that as the tooth height increases, the flatness of the press-in damage surface increases, and the results will be closer to the press-shear test. As the spacing increases, the maximum damage angle and the damage surface between the grooves gradually decrease. The tooth angle has little effect on the friction angle, but cohesion decreases significantly when exceeds 60°. [ABSTRACT FROM AUTHOR]

Reducing the number of design changes in vehicle seat development is critical for minimizing both production cost and product lead time. Generally, discrepancies in measured dimensional specifications of vehicle-seat prototypes and computer-aided design (CAD) models cause significant quality control issues of the finished products. Although three-dimensional (3D) scanning technology enables the efficient evaluations and inspection processes of vehicle-seat prototypes, many evaluation processes require time-consuming tasks. This paper proposes an automated system for evaluating a geometrical consistency between a 3D scan of a prototype and the original CAD model. In the current study, the existing evaluation processes conducted by seat engineers were examined by survey questionnaires. The survey responses were analyzed to define a standardized evaluation process for the automated system. Various computational algorithms, including a function-based scan-to-CAD registration, standard seat dimension estimation, and template-based reporting algorithms, were developed to evaluate the scan and CAD consistency automatically. The developed system not only reduced over 99 % of the evaluation time (on average, existing method: > 2 hrs per seat and system method: < 5 min per seat) but also increased the repeatability of evaluations. Furthermore, the system can collect dimensions of diverse seat designs, prototypes, and products to construct a database of seat dimensions for benchmarking and design improvement. [ABSTRACT FROM AUTHOR]

Copyright of Agricultural Engineering is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper we propose a novel software, named ForestTaxator, supporting terrestrial laser scanning data processing, which for dendrometric tree analysis can be divided into two main processes: tree detection in the point cloud and development of three-dimensional models of individual trees. The usage of genetic algorithms to solve the problem of tree detection in 3D point cloud and its cross-sectional area approximation with ellipse-based model is also presented. The detection and approximation algorithms are proposed and tested using various variants of genetic algorithms. The work proves that the genetic algorithms work very well: the obtained results are consistent with the reference data to a large extent, and the time of genetic calculations is very short. The attractiveness of the presented software is due to the fact that it provides all necessary functionalities used in the forest inventory field. The software is written in C# and runs on the .NET Core platform, which ensures its full portability between Windows, MacOS and Linux. It provides a number of interfaces thus ensuring a high level of modularity. The software and its code are made freely available. [ABSTRACT FROM AUTHOR]

Objective. The accurate localization of electroencephalography (EEG) electrode positions is crucial for accurate source localization. Recent advancements have proposed alternatives to labor-intensive, manual methods for spatial localization of the electrodes, employing technologies such as 3D scanning and laser scanning. These novel approaches often integrate magnetic resonance imaging (MRI) as part of the pipeline in localizing the electrodes. The limited global availability of MRI data restricts its use as a standard modality in several clinical scenarios. This limitation restricts the use of these advanced methods. Approach. In this paper, we present a novel, versatile approach that utilizes 3D scans to localize EEG electrode positions with high accuracy. Importantly, while our method can be integrated with MRI data if available, it is specifically designed to be highly effective even in the absence of MRI, thus expanding the potential for advanced EEG analysis in various resource-limited settings. Our solution implements a two-tiered approach involving landmark/fiducials localization and electrode localization, creating an end-to-end framework. Main results. The efficacy and robustness of our approach have been validated on an extensive dataset containing over 400 3D scans from 278 subjects. The framework identifies pre-auricular points and achieves correct electrode positioning accuracy in the range of 85.7% to 91.0%. Additionally, our framework includes a validation tool that permits manual adjustments and visual validation if required. Significance. This study represents, to the best of the authors' knowledge, the first validation of such a method on a substantial dataset, thus ensuring the robustness and generalizability of our innovative approach. Our findings focus on developing a solution that facilitates source localization, without the need for MRI, contributing to the critical discussion on balancing cost effectiveness with methodological accuracy to promote wider adoption in both research and clinical settings., (Creative Commons Attribution license.)

Context: Breast development is an important outcome for trans women receiving gender affirming hormone therapy (GAHT). Limited breast development has been reported, possibly because of testosterone exposure during puberty. The impact of puberty suppression (PS) on breast development is unclear., Objective: To investigate the impact of PS and timing of PS prior to GAHT on breast volume and satisfaction., Design: Cross-sectional study., Setting: Tertiary gender identity clinic., Participants: 60 trans women (aged 17-57 years) after 4.5±1.7 years of GAHT were included of whom 23 initiated PS early in puberty (Tanner stage G2-3), 17 late in puberty (Tanner stage G4-5), and 20 started GAHT in adulthood without prior PS., Main Outcome Measures: Breast volume measured with a 3D scanner and breast satisfaction measured with a questionnaire. Comparisons of breast volumes were adjusted for fat percentage., Results: Median breast volume was 115ml (IQR 68; 203), i.e. bra cup-size

Aims: To test whether an index based on the combination of demographics and body volumes obtained with a multisensor 3D body volume (3D-BV) scanner and biplane imaging using a mobile application (myBVI®) will reliably predict the severity and presence of metabolic syndrome (MS)., Methods and Results: We enrolled 1280 consecutive subjects who completed study protocol measurements, including 3D-BV and myBVI®. Body volumes and demographics were screened using the least absolute shrinkage and selection operator to select features associated with an MS severity score and prevalence. We randomly selected 80% of the subjects to train the models, and performance was assessed in 20% of the remaining observations and externally validated on 133 volunteers who prospectively underwent myBVI® measurements. The mean ± SD age was 43.7 ± 12.2 years, 63.7% were women, body mass index (BMI) was 28.2 ± 6.2 kg/m 2 , and 30.2% had MS and an MS severity z -score of -0.2 ± 0.9. Features β coefficients equal to zero were removed from the model, and 14 were included in the final model and used to calculate the body volume index (BVI), demonstrating an area under the receiving operating curve (AUC) of 0.83 in the validation set. The myBVI® cohort had a mean age of 33 ± 10.3 years, 61% of whom were women, 10.5% MS, an average MS severity z -score of -0.8, and an AUC of 0.88., Conclusion: The described BVI model was associated with an increased severity and prevalence of MS compared with BMI and waist-to-hip ratio. Validation of the BVI had excellent performance when using myBVI®. This model could serve as a powerful screening tool for identifying MS., Competing Interests: Conflict of interest: Select Research (Worcester, UK), the company that designed the multisensor 3D-BV scanning system technology, provided the scanner used for this and other studies at Mayo Clinic and has a licence agreement over 3D-BV measurement technology. Mayo Clinic and authors J.R.M.-I., and F.L.-J. may receive financial benefits from this technology, but at no point will Mayo Clinic benefit financially from its use for the care of patients at the clinic. All other authors declare no conflict of interest., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Foot morphology and arch integrity do not remain constant during a running bout. Previous studies have reported inconsistent changes in foot sizes and arch parameters and this discrepancy may be related to the variation in their test duration, e.g., 15-min treadmill run vs. 30 KM trial. Hence, this study sought to evaluate the change in foot morphology, arch integrity and bilateral symmetry after a 10 KM run among 19 male recreational runners. Before and after the run, a portable foot scanner was used to capture the 3-dimensional foot images and measure foot dimensions in both weight-bearing and non-weight-bearing conditions. Foot arch integrity was quantified by arch height ratio, arch height index, and arch stiffness index (ASI). Bilateral symmetry was evaluated by calculating the symmetry index. Increased foot length ( p = 0.007; η p 2 = 0.18) and decreased ball girth ( p = 0.038; η p 2 = 0.11) were demonstrated following the run with absolute differences of less than 2 mm. Navicular height, dorsum height, arch height ratio and arch height index significantly decreased after the run ( p < 0.001; η p 2 ≥0.30) whereas ASI increased ( p < 0.001, η p 2 = 0.33) and navicular height drop reduced ( p < 0.001, η p 2 = 0.37). Significances of symmetry index were only demonstrated for navicular height ( p = 0.019, effect size = 0.37) and arch height ratio ( p = 0.019, effect size = 0.42). A few changes in foot morphology were detected but a reduction in foot arch height was demonstrated, which may give shoe manufacturers insights into shoe design. Male recreational runners were recommended to choose shoes with arch support for maintaining foot arch function during a 10 KM run., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Mo, Lu, Li and Zhao.)

3D scanning measurements are gaining popularity every year. Quick inspections on already captured point clouds are easy to prepare with the use of modern software and machine learning. To achieve repeatability and accuracy, some surface and measurement issues should be considered and resolved before the inspection. Large numbers of manufacturing scans are not intended for manual correction. This article is a case study of a small surface inspection of a turbine guide vane based on 3D scans. Small surface errors cannot be neglected as their incorrect inspection can result in serious faults in the final product. Contour recognition and deletion seem to be a rational method for making a scan inspection with the same level of accuracy as we have now for CMM machines. The main reason why a scan inspection can be difficult is that the CAD source model can be slightly different from the inspected part. Not all details are always included, and small chamfers and blends can be added during the production process, based on manufacturing standards and best practices. This problem does not occur during a CMM (coordinate measuring machine) inspection, but it may occur in a general 3D scanning inspection. [ABSTRACT FROM AUTHOR]

Acquiring an accurate 3D scan of the human hand is a challenging task, mainly due to the complicated geometry and the instability of the hand. In this paper, we present a low-cost photogrammetry-based scanner that is designed for scanning the human hand. The scanner has fifty modules, each has a Raspberry Pi with an 8-megapixels camera. They are uniformly positioned in two parallel frames and 96% of a hand surface can be viewed by at least 3 cameras. Using the timestamp method, we synchronize the shutters of the 50 cameras within the range of 80 ms to minimize the influence of the instability of the hand. Moreover, the scanner is easy to build with its modular design, and easy to operate with a laptop that is connected to the system by WiFi. Using a 3D printed prosthetic hand, we compared the 3D scanning accuracy of the proposed scanner with the Artec Spider® scanner. The mean absolute error between the two scans is 0.62 ± 0.28 mm. It is concluded that the proposed hand scanner can be used as a low-cost yet accurate tool in many applications, such as personalized product design.

The foot is a vital organ, as it stabilizes the impact forces between the human skeletal system and the ground. Hence, precise foot dimensions are essential not only for custom footwear design, but also for the clinical treatment of foot health. Most existing research on measuring foot dimensions depends on a heavy setup environment, which is costly and ineffective for daily use. In addition, there are several smartphone applications online, but they are not suitable for measuring the exact foot shape for custom footwear, both in clinical practice and public use. In this study, we designed and implemented computer-vision-based smartphone application OptiFit that provides the functionality to automatically measure the four essential dimensions (length, width, arch height, and instep girth) of a human foot from images and 3D scans. We present an instep girth measurement algorithm, and we used a pixel per metric algorithm for measurement; these algorithms were accordingly integrated with the application. Afterwards, we evaluated our application using 19 medical-grade silicon foot models (12 males and 7 females) from different age groups. Our experimental evaluation shows that OptiFit could measure the length, width, arch height, and instep girth with an accuracy of 95.23%, 96.54%, 89.14%, and 99.52%, respectively. A two-tailed paired t-test was conducted, and only the instep girth dimension showed a significant discrepancy between the manual measurement (MM) and the application-based measurement (AM). We developed a linear regression model to adjust the error. Further, we performed comparative analysis demonstrating that there were no significant errors between MM and AM, and the application offers satisfactory performance as a foot-measuring application. Unlike other applications, the iOS application we developed, OptiFit, fulfils the requirements to automatically measure the exact foot dimensions for individually fitted footwear. Therefore, the application can facilitate proper foot measurement and enhance awareness to prevent foot-related problems caused by inappropriate footwear.

3D scanning measurements are gaining popularity every year. Quick inspections on already captured point clouds are easy to prepare with the use of modern software and machine learning. To achieve repeatability and accuracy, some surface and measurement issues should be considered and resolved before the inspection. Large numbers of manufacturing scans are not intended for manual correction. This article is a case study of a small surface inspection of a turbine guide vane based on 3D scans. Small surface errors cannot be neglected as their incorrect inspection can result in serious faults in the final product. Contour recognition and deletion seem to be a rational method for making a scan inspection with the same level of accuracy as we have now for CMM machines. The main reason why a scan inspection can be difficult is that the CAD source model can be slightly different from the inspected part. Not all details are always included, and small chamfers and blends can be added during the production process, based on manufacturing standards and best practices. This problem does not occur during a CMM (coordinate measuring machine) inspection, but it may occur in a general 3D scanning inspection.

Inspired by the ability of water to assimilate any shape, if being poured into it, regardless if flat, round, sharp, or pointy, we present a novel, high-quality meshing method. Our algorithm creates a triangulated mesh, which automatically refines where necessary and accurately aligns to any target, given as mesh, point cloud, or volumetric function. Our core optimization iterates over steps for mesh uniformity, point cloud projection, and mesh topology corrections, always guaranteeing mesh integrity and ϵ -close surface reconstructions. In contrast with similar approaches, our simple algorithm operates on an individual vertex basis. This allows for automated and seamless transitions between the optimization phases for rough shape approximation and fine detail reconstruction. Therefore, our proposed algorithm equals established techniques in terms of accuracy and robustness but supersedes them in terms of simplicity and better feature reconstruction, all controlled by a single parameter, the intended edge length. Due to the overall increased versatility of input scenarios and robustness of the assimilation, our technique furthermore generalizes multiple established approaches such as ballooning or shrink wrapping. [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]

Abstract Introduction The aim of this study was to evaluate the intraoperative revision rate and reasons for revision following 3D imaging in the management of dislocated articular tibial plateau fractures based on a large patient sample. Methods This retrospective cohort study included all patients who underwent open reduction and internal fixation due type B or C tibial plateau fracture according to the AO/OTA classification between August 2001 and December 2017 using intraoperative cone beam CT (3D imaging) for the analysis of fracture reduction and implant placement. The findings of the 3D scan were categorized regarding the amount and type of revision. Furthermore, demographic data was examined. Results Five hundred and fifty-nine consecutive fractures were included in the study. Evaluation of the image data records revealed an intraoperative revision due to the usage of 3D imaging in 148 out of 559 cases (26.5%). The most common reasons for an intraoperative revision were insufficient fracture reduction (114 cases) and screw length (21 cases). Conclusion This study reveals indications for a limited analysis of fracture reduction and implant placement during the operative treatment of dislocated articular tibial plateau fractures using conventional fluoroscopy. In view of the high revision rate during open reduction and internal fixation of tibial plateau fractures due to 3D imaging the usage of intraoperative cone beam, CT may be considered. If this is not possible, a postoperative computed tomography may therefore be reasonable.

Strumigenys is one of the most diverse ant genera in the world and arguably the most morphologically diverse, exhibiting an exceptional range of mandible shape and function. A new species, Strumigenys ayersthey sp. nov., discovered in the Choco region of Ecuador is described. With two morphological characters, this species is shown to be a morphologically unique outlier among Strumigenys globally, having predominately smooth and shining cuticle surface sculpturing and long trap-jaw mandibles. Using ƒÊCT scans, we produced 3D images of the worker ant and static images to examine and compare mandible articular morphologies with most morphologically similar members of the mandibularis species group. Cuticular, pilosity, and articular mandible morphological differences supports placing the new species in its own new species group. [ABSTRACT FROM AUTHOR]

Lateral wedges are a common conservative treatment for medial knee osteoarthritis (OA). However, use of lateral wedges might increase the ankle eversion moment. To minimize the risk of ankle symptoms, lateral wedges with custom arch support are suggested. However, the manufacturing process of a custom foot orthosis (FO) is complicated, labor-intensive, and time-consuming. The technology of 3D printing is an ideal method for mass customization. Therefore, the purpose of this study was to develop custom FOs using 3D-printing techniques and to evaluate the effects of 3D-printed FOs in patients with knee OA. Fifteen patients with medial knee OA were enrolled into this study. Kinematic and kinetic data were collected during walking by using an optical motion capture system. A paired-sample t-test was conducted to compare biomechanical variables under two conditions: walking in standard shoes (Shoe) and walking in shoes embedded with 3D-printed FOs (Shoe + FO). The results show that the first and second peak knee adduction moments were significantly reduced by 4.08% and 9.09% under the Shoe + FO condition. The FOs alter the biomechanical environment in a way that reduces the variables used to infer abnormal loads at the knee and ankle that could result in painful symptoms. [ABSTRACT FROM AUTHOR]

Copyright of Kieferorthopädie: die Zeitschrift für die Praxis is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper deals with an experimental analysis of stress prediction and simulation prior to 3D printing via the selective laser melting (SLM) method and the subsequent separation of a printed sample from a base plate in two software programs, ANSYS Addictive Suite and MSC Simufact Additive. Practical verification of the simulation was performed on a 3Dprinted topologically optimized part made of AISI 316L stainless steel. This paper presents a typical workflow for working with metallic 3D printing technology and the state-of-the-art knowledge in the field of stress analysis and simulation of printed components. The paper emphasizes the role of simulation software for additive production and reflects on their weaknesses and strengths as well, with regard to their use not only in science and research but also in practice. [ABSTRACT FROM AUTHOR]

Purpose: To assess precise topographic changes of the breast, objective documentation and evaluation of pre- and postoperative results are crucial. New technologies for mapping the body using digital, three-dimensional surface measurements have offered novel ways to numerically assess the female breast. Due to the lack of clear demarcation points of the breast contour, the selection of landmarks on the breast is highly dependent on the examiner, and, therefore, is prone to error when conducting before-after comparisons of the same breast. This study describes an alternative to volumetric measurements, focusing on topographic changes of the female breast, based on three-dimensional scans. Method: The study was designed as an interventional prospective study of 10 female volunteers who had planned on having aesthetic breast augmentation with anatomical, textured implants. Three dimensional scans of the breasts were performed intraoperatively, first without and then with breast implants. The topographic change was determined as the mean distance between two three-dimensional layers before and after augmentation. This mean distance is defined as the Topographic Shift. Results: The mean implant volume was 283 cc (SD = 68.6 cc, range = 210–395 cc). The mean Topographic Shift was 7.4 mm (SD = 1.9 mm, range = 4.8–10.7 mm). The mean Topographic Shifts per quadrant were: I: 8.0 mm (SD = 3.3 mm); II: 9.2 mm (SD = 3.1 mm); III: 6.9 mm (SD = 3.5 mm); IV: 1.9 mm (SD = 4.3 mm). Conclusion: The Topographic Shift, describing the mean distance between two three-dimensional layers (for example before and after a volume changing therapy), is a new approach that can be used for assessing topographic changes of a body area. It was found that anatomical, textured breast implants cause a topographic change, particularly on the upper breast, in quadrant II, the décolleté. [ABSTRACT FROM AUTHOR]

This work grew out of a desire to investigate the digital surveying process used in phases to define the concept of a morphologically complex product such as an automobile. This investigation was conducted by analysing the final steps of the first ten editions of the Specialized Master course in Transportation & Automobile Design at Politecnico di Milano University. In analysing the procedures to create the presentation models starting with clay studio models, four protocols were standardized and compared. Following this, some suggestions and guidelines were summarized to ensure that faithfulness to the design intent during the process would not fail. The ultimate goal of this work is to highlight the critical aspects of a process that is based on a quantitative method (the digital survey), but that requires a qualitative approach to be truly effective.

During archaeological research carried out in Nasielsk, Poland in 2006 by Dr. M. Błoński, a fragment of an ornamented sickle handle was found. It most likely dates to the 2nd half of the 10th century, but may have been made as late as the mid-11th century. The sickle with a movable blade is interpreted as belonging to the equipment of an elite horse warrior. Many finds of this type known from unusual medieval deposits suggests their special, symbolic meaning and a connection with the military sphere. The artefact is ornamented with a variation of the Borre ring-chain pattern – specifically, the Pomeranian school of Scandinavian-Insular decoration. The origins of this style emerged in the 10th century with the combining of Celtic, English, and Scandinavian elements – and it was developed intensively in western Pomerania. The artefact from Nasielsk has only partially survived. The preserved fragment of the handle was 3D scanned using a structured light scanner and photogrammetry software. In order to make a 3D reconstruction, documentation of a second, not available fragment was also used. Moreover, certain analogies from early medieval folded sickles were analyzed. The most important questions concerned the shape of the blade, the continuation of the ornament, its design features, and a proper visualization of the reconstruction.

A crucial activity in architectural and archaeological conservation research is the process of synthesising information in which the researcher records collected field data in the form of a planar drawing. This labour-intensive stage is significantly improved by automated systems which support the measurement work. Some of these are programs that convert sets of photographs into virtual and spatial models.

This paper presents methods for continuous condition monitoring of railway switches and crossings (S&C, turnout) via sleeper-mounted accelerometers at the crossing transition. The methods are developed from concurrently measured sleeper accelerations and scanned crossing geometries from six in situ crossing panels. These measurements combined with a multi-body simulation (MBS) model with a structural track model and implemented scanned crossing geometries are used to derive the link between the crossing geometry condition and the resulting track excitation. From this analysis, a crossing condition indicator Cλ1−λ2, γ is proposed. The indicator is defined as the root mean square (RMS) of a track response signal γ that has been band-passed between frequencies corresponding to track deformation wavelength bounds of λ1 and λ2 for the vehicle passing speed (f = v/ λ). In this way, the indicator ignores the quasi-static track response with wavelengths predominantly above λ1 and targets the dynamic track response caused by the kinematic wheel-crossing interaction governed by the crossing geometry. For the studied crossing panels, the indicator C1−0.2 m, γ (λ1=1 and λ2=0.2) was evaluated for γ = u, v, or a as in displacements, velocities, and accelerations, respectively. It is shown that this condition indicator has a strong correlation with vertical wheel–rail contact forces that is sustained for various track conditions. Further, model calibrations were performed to measured sleeper displacements for the six investigated crossing panels. The calibrated models show (1) a good agreement between measured and simulated sleeper displacements for the lower frequency quasi-static track response and (2) improved agreement for the dynamic track response at higher frequencies. The calibration also improved the agreement between measurements and simulation for the crossing condition indicator demonstrating the value of model calibration for condition monitoring purposes.

Abstract Background The measurement of maximal head circumference is a standard procedure in the examination of childrens’ cranial growth and brain development. The objective of the study was to evaluate the validity of maximal head circumference to cranial volume in the first year of life using a new method which includes ear-to-ear over the head distance and maximal cranial length measurement. Methods 3D surface scans for cranial volume assessment were conducted in this method comparison study of 44 healthy Caucasian children (29 male, 15 female) at the ages of 4 and 12 months. Results Cranial volume increased from measurements made at 4 months to 12 months of age by an average of 1174 ± 106 to 1579 ± 79 ml. Maximal cranial circumference increased from 43.4 ± 9 cm to 46.9 ± 7 cm and the ear-to ear measurement increased from 26.3 ± 21 cm to 31.6 ± 18 cm at the same time points. There was a monotone association between maximal head circumference (HC) and increase in volume, yet a backwards inference from maximal circumference to the volume had a predictive value of only 78% (adjusted R2). Including the additional measurement of distance from ear to ear strengthened the ability of the model to predict the true value attained to 90%. The addition of the parameter skull length appeared to be negligible. Conclusion The results demonstrate that for a distinct improvement in the evaluation of a physiological cranial volume development, the additional measurement of the ear-to ear distance using a measuring tape is expedient, and, especially for cases with pathological skull changes, such as craniosynostosis, ought to be conducted.

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The article presents the results of research aimed at redesigning a jewelry product with the use of modern reverse engineering methods. A detailed review of the literature was conducted and the essence of the application of this technology in the era of Industry 4.0 was presented. The 3D digitization of the research object was performed with the use of Aicon SmartSCAN-HE R8 and DAVID-SLS3 scanners. The obtained better quality file was edited in Autodesk Meshmixer 3.5 software. On the basis of the created model, a 3D print was made using FDM (Fused Deposition Modeling) and DPP (Daylight Polymer Printing) technology with two different materials - HIPS (High Impact Polystyrene) and photopolymer casting resin. The final stage of the work was the measurement of the surface roughness of the B101 (CuSn10P) tin-phosphorus alloy castings made using the method of investment casting. [ABSTRACT FROM AUTHOR]

Knowing to what extent lithic cores have been reduced through knapping is an important step toward understanding the technological variability of lithic assemblages and disentangling the formation processes of archaeological sites. In addition, it is a good complement to more developed studies of reduction intensity in retouched tools and provides information on raw material management or site occupation dynamics. This paper presents a new methodology for estimating the intensity of reduction in cores and tools on cobbles, the Volumetric Reconstruction Method (VRM). It is based on a correction of the dimensions (length, width, and thickness) of each core from an assemblage. The median values of thickness and platform thickness of the assemblage’s flakes are used as corrections for the cores’ original dimensions, after its diacritic analysis. Then, based on these new dimensions, the volume or mass of the original blank are reconstructed using the ellipsoid volume formula. The accuracy of this method was experimentally tested, reproducing a variety of possible archaeological scenarios. The experimental results demonstrate a high inferential potential of the VRM, both in estimating the original volume or mass of the original blanks and in inferring the individual percentage of reduction for each core. The results of random resampling demonstrate the applicability of VRM to not size-biased archaeological contexts. [ABSTRACT FROM AUTHOR]

One of the largest species in its genus, Odontomachus davidsoni Hoenle, Lattke & Donoso, sp. nov. is described from workers and queens collected at lowland forests in the Chocó-Darién bioregion in coastal Ecuador. The workers are characterized by their uniform red coloration, their large size (16-18 mm body length), and their frontal head striation that reaches the occipital margin. DNA barcodes (COI) and high resolution 2D images of the type material are provided, as well as an updated key for the Neotropical species of Odontomachus. In addition, a three-dimensional digital model of the worker holotype and a paratype queen scanned with DISC3D based on photogrammetry is presented, for the first time in a species description. Findings of large and conspicuous new species are uncommon around the world and suggest that these Ecuadorian rainforests may conceal many more natural treasures that deserve conservation. [ABSTRACT FROM AUTHOR]

Purpose: Three-dimensional scanning technology was used to measure the expansion of the area and size of auricular skin to meet the normal standard of the external ear before ear reconstruction among microtia patients. Materials and Methods: The skin surface area of microtia patients was measured by three-dimensional scanner: the surface area (S), vertical length (A), vertical curve length (B), transverse length (C), transverse curve length data (D), and then taking the average. Corresponding measurements in healthy adults were also obtained: surface area (S0), the vertical curve length (B0), and transverse curve length (D0) of the normal external ear were obtained by scanning normal adult male ears with reference to the range of the vertical length and the transverse straight length. Mean surface area (S and S0), vertical curve length (B and B0), and transverse curve length (D and D0) were compared between microtia patients and healthy adults. Results: The surface area, vertical curve length, and transverse curve length were statistically significantly higher among healthy adults. Conclusions: With the amount of expanded water injection of 120–130 ml, the expanded skin still does not reach the standard of the normal external ear in terms of skin surface area and size. Level of Evidence IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266. [ABSTRACT FROM AUTHOR]