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The escape of pedestrians in the subway station is hampered by floods created by heavy rain. In order to explore the critical flood level in a subway station so that pedestrians can escape safely, the case study of the Mingxiu Road subway station in Nanning, China, was conducted using numerical simulation techniques. In total, 30 groups of sample pedestrians with different walking speeds and numbers were randomly generated by the Monte Carlo method, and 3D simulation software was used for escape simulation. The simulated escape data were put into the SVM model, and the maximum pedestrian capacity and minimum speed of pedestrians were solved successfully with different conditions of the Mingxiu Road subway station. Then, a 1:1 contour model of the pedestrian was constructed to simulate the flood resistance of the pedestrian escaping at the minimum speed. The flood resistance and the friction force between the pedestrian and the ground were compared to calculate the critical escape flood level height, and the critical escape flood level height of an adult, child, and elder was 87.4 cm,75.5 cm, and 83.0 cm, respectively. [ABSTRACT FROM AUTHOR]

Numerical study of various physical phenomena in three dimensions has become a necessity to better understand the physical process than in two dimensions. Thus, in this paper, the code is elaborated to be adapted to the simulation of heat transfer in three dimensions. The numerical simulations are performed using a hybrid method. This method is based on the lattice Boltzmann approach for the computation of velocities, and on the finite difference technique for the calculation of temperature. The used numerical code is validated by examining the free convection in a cubic enclosure filled with air. Then, the analysis of the heat exchange between two cold vertical walls and a heated block located at the center of a cubic cavity is considered. The performed simulations showed that for a small value of the Rayleigh number (Ra=10³ for example), the fluid exchanges its heat almost equally with all hot surfaces of the obstacle. However, for large values of Ra (Ra≥104), the numerical results found showed that the heat exchange rate is greater on the bottom face compared to the other faces of the obstacle. [ABSTRACT FROM AUTHOR]

Abstract Aim To evaluate the correspondence between the interproximal reduction (IPR) performed clinically and that programmed in ClinCheck® and further assess which teeth showed an amount of implemented IPR (I-IPR) that corresponds with that programmed in ClinCheck®. Materials and methods Pre- (T0) and post-treatment (T1) ClinCheck® digital models for 75 subjects (30 males and 45 females), mean age (38 ± 15) years, were included. To calculate the amount of I-IPR, Ortho Analyzer software (3Shape, Copenhagen, Denmark) was used to measure the mesiodistal widths for the maxillary and mandibular teeth from second premolar to the contralateral second premolar on the initial (T0) and final (T1) STL models. I- IPR performed by tooth was obtained by comparing the mesiodistal width of each tooth at T0 and T1. The amount of programmed IPR (P-IPR) in ClinCheck® was compared to that implemented clinically using the following formula: IPR difference = (P-IPR) − (I-IPR). Results Statistically significant differences were observed between the average value of digitally programmed and implemented IPR per tooth for both the maxillary (p

In high-frequency electronic equipment and power electronic devices, the dynamic performance of switching devices is one of the important indicators, and a double-pulse test circuit is usually used to test the dynamic performance of switching devices. In order to reduce the stray inductance existing in the test circuit, a double-pulse test circuit structure based on PCB is firstly proposed, and then the basic principle of using the integral calculation method to extract the PCB stray inductance is analyzed. Then the 3D model of the PCB is established, and the PCB stray inductance extraction based on 3D simulation is completed. Finally, a 1200V/100A double-pulse test experimental platform is built. By comparing the three-dimensional simulation results with the numerical calculation results using the integral method under the double-pulse test experiment, the accuracy and effectiveness of the three-dimensional simulation method proposed in this paper are verified.

Objective: To validate the newly developed artificial intelligence (AI)-assisted simulation by evaluating the speed of three-dimensional (3D) reconstruction and accuracy of segmental volumetry among patients with liver tumors.Background: AI with a deep learning algorithm based on healthy liver computer tomography images has been developed to assist three-dimensional liver reconstruction in virtual hepatectomy.Methods: 3D reconstruction using hepatic computed tomography scans of 144 patients with liver tumors was performed using two different versions of Synapse 3D (Fujifilm, Tokyo, Japan): the manual method based on the tracking algorithm and the AI-assisted method. Processing time to 3D reconstruction and volumetry of whole liver, tumor-containing and tumor-free segments were compared.Results: The median total liver volume and the volume ratio of a tumor-containing and a tumor-free segment were calculated as 1035 mL, 9.4%, and 9.8% by the AI-assisted reconstruction, whereas 1120 mL, 9.9%, and 9.3% by the manual reconstruction method. The mean absolute deviations were 16.7 mL and 1.0% in the tumor-containing segment and 15.5 mL and 1.0% in the tumor-free segment. The processing time was shorter in the AI-assisted (2.1 vs. 35.0 min; p < 0.001).Conclusions: The virtual hepatectomy, including functional liver volumetric analysis, using the 3D liver models reconstructed by the AI-assisted methods, was reliable for the practical planning of liver tumor resections. [ABSTRACT FROM AUTHOR]

This paper proposes a virtual display method suitable for a weft-knitted seamless kneepad. The purpose of this study is to realize the virtual display of complete weft-knitted products, and it has the advantage of speed to display the virtual display results online in real-time. The basic loop of the model is controlled by up to eight characteristic points and the yarn path is fitted by a three-dimensional spline curve. First, the characteristic point coordinates of the seamless weft-knitted kneepad in the plane state were calculated, and then the corresponding spatial coordinate transformation matrix was selected according to the corresponding mesh of each loop to calculate the characteristic point coordinates in the wearing state. Finally, the virtual display model of the seamless weft-knitted kneepad was rendered by tubeline geometry. The virtual display of the weft-knitted kneepad is realized by the joint programming of Visual Studio and WebGL. The results show that the structure model can achieve the virtual display of the kneepad with high efficiency. This method has strong real-time performance and practicability. [ABSTRACT FROM AUTHOR]

As one essential indicator of surface integrity, residual stress has an important influence on the fatigue performance of aero engines' thin-walled parts. Larger compressive or smaller tensile residual stress is more prone to causing fatigue cracks. To optimize the state of residual stress, the relationship between the surface residual stress and the machining conditions is studied in this work. A radial basis function (RBF) neural network model based on simulated and experimental data is developed to predict the surface residual stress for multi-axis milling of Ti-6Al-4V titanium alloy. Firstly, a 3D numerical model is established and verified through a cutting experiment. These results are found to be in good agreement with average absolute errors of 11.6% and 15.2% in the σx and σy directions, respectively. Then, the RBF neural network is introduced to relate the machining parameters with the surface residual stress using simulated and experimental samples. A good correlation is observed between the experimental and the predicted results. The verification shows that the average prediction error rate is 14.4% in the σx direction and 17.2% in the σy direction. The effects of the inclination angle, cutting speed, and feed rate on the surface residual stress are investigated. The results show that the influence of machining parameters on surface residual stress is nonlinear. The proposed model provides guidance for the control of residual stress in the precision machining of complex thin-walled structures. [ABSTRACT FROM AUTHOR]

Small-scaled linear cutting tests were first performed to study the influence of penetration on fracture characteristics by a CCS (constant cross-section) cutter. The results indicate that the increase in penetration (ranging from 2.5 mm to 5.5 mm) effectively increases chip masses between cuts and further promotes cutting efficiency. To further understand the fracture mechanism for various penetrations, 3D numerical simulations were performed using PFC 3D. The numerical fracture characteristics agree well with laboratory tests. In addition, the dynamic stress evolution analysis clearly shows that the increase in rolling force frequently results in stress concentrations in rock specimens. When stresses concentrate into critical values, fractures occur. Subsequently, these fracture propagations frequently result in stress dissipations and decreases in rolling force. Thus, the relation between the fluctuations of rolling force and the rock fractures is revealed. In addition, the increase in penetration results in the promoted stress concentrations. This phenomenon can explain why the increased penetration can result in severer fractures. [ABSTRACT FROM AUTHOR]

Copyright of Industria Textila is the property of Institutul National de Cercetare-Dezvoltare pentru Textile si Pielarie 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.)

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office 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.)

On 5 April 2021, a high-position landslide occurred in Tiejiangwan, Liujiang Town of Hongya County, Sichuan Province, China. The detached mass transformed into a debris avalanche traveled about 1300 m with an elevation difference of 665 m and caused three fatalities. Then landslide deposits were initiated by continuous rainfall and evolved to a debris flow five days later, forming a secondary disaster chain. The rapid characterization of a landslide-debris flow chain (LDC) is a critical step in remediation works and future early warning of failure. This paper proposes a rapid disaster information integration and assessment method for providing information on LDC occurrence, failure mechanisms, and potential hazard-affected areas via examining and characterizing the Tiejiangwan LDC based on multi-method including geomorphological mapping, structural characterization, kinematic analysis and numerical simulation. The results suggested that the first landslide initiated from a mountain ridge that experienced historical deformation extended over the fractured argillaceous siltstones. Constrained by three discontinuity sets, the failure mode was determined as planar failure along a sub-vertical defect. The cause of first landslide can be attributed to a jointed effect of structural plane, tectonic activity, terrain and slope structure, while rainfall is the dominating triggering factor. Deposits with loose structure subjected to persistent rainfall and gully topography contribute to the occurrence of secondary debris flow. Using UAV and LiDAR identification, the unstable elements in the surrounding cliffs of the source area are derived and a three-dimensional simulation was implemented to detect the energy, velocity, height and reach of detached blocks. The proposed method leads to rapid characterization of LDC and assists the evaluation of cliff instability of these environments. Highlights: We proposed a rapid and integrated assessment system for landslide-debris flow chain occurrence, failure mechanisms, and potential hazard-affected areas identification. Quantitative study was conducted on the evolution from landslide deposits to debris flow. 3D simulation was performed to reveal the runout behaviors of surrounding potential dangerous rockfall areas. [ABSTRACT FROM AUTHOR]

Introduction: Discerning whether range of motion (ROM) is restricted by morphology or other pain sources is challenging in patients with femoroacetabular impingement syndrome (FAIS). Computed tomography (CT) motion simulation provides a hypothetical ROM based on morphology. This study aimed to explore associations between ROM measured using CT motion simulation and maximum passive ROM measured clinically using three dimensional (3D) motion analysis in patients with FAIS, prior to and post arthroscopic hip surgery. Materials and methods: Eight males with FAIS (in total 12 hip joints) were included in this explorative feasibility study. Participants were examined using CT according to a low-dose protocol prior to and 7-months post arthroscopic surgery. Software was used to simulate at which ROM the impingement would occur. With the hip in 90 degrees' flexion, maximum passive range of internal hip rotation, and maximum passive internal hip rotation coupled with adduction was examined clinically using 3D motion analysis pre- and postoperatively. Spearman rank correlation coefficients and linear regressions examined associations between methods. Results: Preoperatively, the correlation between maximum internal hip rotation measured using CT motion simulation and 3D motion analysis was strong (r = 0.71, p = 0.009). Linear regressions demonstrated that maximal internal rotation measured using CT motion simulation was predominantly larger than when measured using 3D motion analysis. Postoperatively, and when maximum internal rotation was coupled with adduction, no correlations were found between the two methods. Conclusions: The hypothetical morphology restricted ROM is larger than clinically assessed pain restricted ROM, both prior to and post hip arthroscopy. These findings suggest that ROM is restricted by pain rather than mechanical, morphology-based impingement in individuals with FAIS. [ABSTRACT FROM AUTHOR]

Three-dimensional (3 D) visualization and simulation programs cannot be used in leather apparel companies prevalently due to the lack of leather material information in the databases. In this study, the properties of different types of leather and fabrics are determined with certain standards and alternatively with FAST (Fabric Assurance by Simple Testing) system, interpreted and defined in the database of Vidya 3 D program. The two-dimensional (2 D) garment patterns prepared in the Assyst CAD program were transferred to the 3 D program, and dress simulations were performed on the virtual mannequin by using the newly defined materials. The sewn dresses and simulations were evaluated by a jury considering similarity success. It has been found that Vidya 3 D program can simulate model and material behaviors realistically by using the data obtained from the FAST system, however, it does not demonstrate the drape parameter precisely, and the software should be improved for this direction. [ABSTRACT FROM AUTHOR]

The fabrication of microflow channels with high accuracy in terms of the optimization of the proposed designs, minimization of surface roughness, and flow control of microfluidic parameters is challenging when evaluating the performance of microfluidic systems. The use of conventional input devices, such as peristaltic pumps and digital pressure pumps, to evaluate the flow control of such parameters cannot confirm a wide range of data analysis with higher accuracy because of their operational drawbacks. In this study, we optimized the circular and rectangular-shaped microflow channels of a 100 μm microfluidic chip using a three-dimensional simulation tool, and analyzed concentration profiles of different regions of the microflow channels. Then, we applied a deep learning (DL) algorithm for the dense layers of the rectified linear unit (ReLU), Leaky ReLU, and Swish activation functions to train and test 1600 experimental and interpolation of data samples which obtained from the microfluidic chip. Moreover, using the same DL algorithm, we configured three models for each of these three functions by changing the internal middle layers of these models. As a result, we obtained a total of 9 average accuracy values of ReLU, Leaky ReLU, and Swish functions for a defined threshold value of 6 × 10 − 5 using the trial-and-error method. We applied single-to-five-fold cross-validation technique of deep neural network to avoid overfitting and reduce noises from data-set to evaluate better average accuracy of data of microfluidic parameters. [ABSTRACT FROM AUTHOR]

An aortopulmonary window is a rare disorder that occurs in 0.1–0.2% of all congenital disorders. Our patient was a 1-month-old boy weighing 4180 g. The patient had heart failure associated with an aortopulmonary window. We used 3-dimensional computer graphic software (Viewtify, SCIEMENT) for diagnosis based on DICOM data from contrast-enhanced computed tomography. This made it easy to identify anatomical landmarks and findings and select the most suitable approach. We avoided stenosis of the right pulmonary artery and aorta. We encountered a case of an aortopulmonary window in which 3-dimensional computer graphic software was helpful in selecting the surgical technique. We report this case using 3-dimensional computer graphic images and present a review of the literature., (© The Author 2024. Published by MMCTS on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Background: Not all surgical osteotomy steps have been properly investigated for their potential impact on surgical accuracy. The main study objective was to investigate the osteotomy parameters that have respectively major and minor impact on coronal and sagittal bony accuracy in medial opening-wedge high tibial osteotomy (MOWHTO)., Methods: Three tibias from an existing 3D MOWHTO osteotomy database were chronologically selected based on segmentation quality, tibial plateau size and the presence of tibial varus. The study consisted of three parts: (I) translating the hinge axis in the coronal plane and switching the osteotomy starting point (30-40 mm) and depth, (II) the hinge axis was rotated stepwise by 10° to perform five simulations, (III) the hinge axis was rotated in the axial plane stepwise by 10° towards anterolateral to perform four simulations (0°, +10°, +20°, +30°). The medial proximal tibial angle (MPTA) and lateral tibial slope were the primary outcomes. Simulations were performed with 5, 10 and 15 mm gap distraction., Results: In the coronal plane, maximum difference in osteotomy depth was 10 mm which represented an MPTA difference of 0.8°-1.1° in 10 mm gap distraction and 1.2°-2.0° in 15 mm gap distraction. Tibial slope remained unchanged. Rotating the hinge axis in the sagittal plane delivered minor changes on both MPTA (<0.5°) and tibial slope (<1.5°) at 10 mm gap distraction. Per 10° of axial rotation of the hinge axis towards anterolateral, the tibial slope increased by 1.0°-1.3° in 10 mm gap distraction while the MPTA remains nearly unchanged., Conclusions: The study showed that the medio-lateral osteotomy length is the main parameter for obtaining bony accuracy in the coronal plane and maintaining a strict perpendicular axial hinge axis position is crucial in preserving the native tibial slope. Correct axial alignment of the hinge axis can be obtained by creating an equal osteotomy depth of the anterior and posterior tibial cortices in the lateral metaphyseal area., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://atm.amegroups.com/article/view/10.21037/atm-23-1870/coif). The authors have no conflicts of interest to declare., (2024 Annals of Translational Medicine. All rights reserved.)

Patients with focal ventricular tachycardia are at risk of hemodynamic failure and if no treatment is provided the mortality rate can exceed 30%. Therefore, medical professionals must be adequately trained in the management of these conditions. To achieve the best treatment, the origin of the abnormality should be known, as well as the course of the disease. This study provides an opportunity to visualize various focal ventricular tachycardias using the Offenburg heart rhythm model. Modeling and simulation of focal ventricular tachycardias in the Offenburg heart rhythm model was performed using CST (Computer Simulation Technology) software from Dessault Systèms. A bundle of nerve tissue in different regions in the left and right ventricle was defined as the focus in the already existing heart rhythm model. This ultimately served as the origin of the focal excitation sites. For the simulations, the heart rhythm model was divided into a mesh consisting of 5354516 tetrahedra, which is required to calculate the electric field lines. The simulations in the Offenburg heart rhythm model were able to successfully represent the progression of focal ventricular tachycardia in the heart using measured electrical field lines. The simulation results were realized as an animated sequence of images running in real time at a frame rate of 20 frames per second. By changing the frame rate, these simulations can additionally be produced at different speeds. The Offenburg heart rhythm model allows visualization of focal ventricular arrhythmias using computer simulations. By selecting the frame rate, the speed of the simulation results can be adjusted accordingly to visualize the electric field lines of focal ventricular tachycardias in more detail. The static and dynamic simulation results could be used in the future for teaching and research, including the training of medical professionals.

In order to alleviate the structural vibrations induced by traffic loads, in this paper, a phonon crystal plate with functionally graded materials is designed based on local resonance theory. The vibration damping performance of the phonon crystal plate is studied via finite element numerical simulation and the band gap is verified via vibration transmission response analysis. Finally, the engineering application mode is simulated to make it have practical engineering application value. The results show that the phonon crystal plate has two complete bandgaps within 0~150 Hz, the initial bandgap frequency is 0.00 Hz, the cut-off frequency is 128.32 Hz, and the internal ratio of 0~100 Hz is 94.13%, which can effectively reduce the structural vibration caused by traffic loads. Finally, stress analysis of the phonon crystal plate is carried out. The results show that phonon crystals of functionally graded materials can reduce stress concentration through adjusting the band gap. The phonon crystal plate designed in this paper can effectively suppress the structural vibration caused by traffic loads, provides a new method for the vibration reduction of traffic infrastructure, and can be applied to the vibration reduction of bridges and their auxiliary facilities.

Garment simulation enables the reduction of physical prototypes, saving time, material and costs. Complete elimination of physical prototypes is not yet possible because simulation is not reliable enough for a robust fit analysis. In addition, predictions of the textile-physical behaviour of virtually available materials would be useful. A new approach is being developed to represent the material and construction properties of textile surfaces, their correlations and their influence on the simulation. Based on the material parameters, conditions for a reliable simulation and prediction of the material behaviour can be derived. This paper first focuses on the distinction between the material properties of the fibres and the construction properties of the yarn and surface.

Understanding the excavation-induced fractured zone (EFZ) around drifts is paramount in the context of the deep geological disposal for nuclear waste since fractures can introduce pathways for the migration of radionuclides. Drifts in the Meuse/Haute-Marne Underground Research Laboratory (URL) have been essentially excavated following the two main directions of major and minor horizontal stresses. Field observations on the two drifts GCS (parallel to major horizontal stress direction) and GED (parallel to minor horizontal stress direction) in the URL show anisotropic shapes of EFZ around drifts through both orientations and anisotropic convergences. These anisotropic responses resulted from the inherent and/or induced anisotropies of the host rock as well as the anisotropic stress field. This study focuses on 3D numerical modelling of excavation-induced anisotropic responses including shape and extent of EFZ, and short-term convergences of drifts. The main assumption is that the failure of claystone material is due to fracturing along weakness planes (ubiquitous joints) and the failure of the rock matrix. The ubiquitous joint failure is represented by perfectly plastic models for both tensile and shear yield functions. Their orientation is determined from the stress state based on the fracture mechanics, which includes tensile, longitudinal splitting and shear (conjugate planes) cracks. The rock matrix is assumed to be elastoplastic with hardening, softening and residual behaviours. Confining pressure dependency for the post-peak behaviour with a brittle–ductile transition is taken into account for the rock matrix. The proposed model is implemented into a commercial numerical software FLAC3D. The main features of the implemented model are shown by the simulation of laboratory triaxial compression tests, as well as field observation within the URL. In particular, comparisons between 3D simulations of GCS and GED drifts with in situ observations shows promising results, which demonstrates advances of present model with respect to existing models. Highlights: •3D modelling of excavation induced anisotropic mechanical responses of COx claystone. •A coupling between weakness planes and elastoplastic rock matrix for rock fracturing. •Stress state controlling the weakness plane occurring and its orientation. •Galleries within Andra URL following both minor and major horizontal stress orientations are considered. •Convergence and damage zone are rather well reproduced by the proposed model. [ABSTRACT FROM AUTHOR]

Copyright of Industria Textila is the property of Institutul National de Cercetare-Dezvoltare pentru Textile si Pielarie 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.)

Using "large-for-size" liver graft, graft-to-recipient weight ratio (GRWR) ≥4%, has been debated in pediatric liver transplantation due to possible graft compartment after abdomen closure. Meticulous preoperative evaluation with three-dimensional (3D) techniques may prevent these problems. This study compared the safety of large-for-size grafts in pediatric living donor liver transplantation (PLDLT) during the eras with or without 3D planning. We defined the 3D era was after November 2017 due to our first implication of 3D printing for surgical planning and subsequently developing a 3D simulation implanting model. From November 2004 to July 2021, we enrolled 30 PLDLT patients with body weight (BW) < 10 kg and categorized them into conventional group: GRWR ≥4% before the 3D era (n = 9), 3D group: GRWR ≥4% in the 3D era (n = 8), and control group: GRWR <4% (n = 13). We followed and compared their clinical outcomes. The 3D group had the lowest BW and the highest graft volume reduction rate, with all receiving modified left lateral segments (LLS), such as reduced LLS (n = 2), hyperreduced LLS (n = 5), and segment 2 monosegment (n = 1). Overall postoperative complications were similar in conventional and control groups but significantly lower in the 3D group (OR 0.06, 95% CI 0.006−0.70, p = 0.025). However, all groups had similar graft and patient survival at 1, 2, and 4 years. Advanced preoperative 3D planning can decrease post-transplant complications and increase the safety of large-for-size grafts in PLDLT. Type of study: Retrospective comparative study; Evidence level: Level III [ABSTRACT FROM AUTHOR]

Background: Breast augmentation is one of the most frequently performed plastic surgery procedures. Providing patients with realistic 3D simulations of breast augmentation outcomes is becoming increasingly common. Until recently, such programs were expensive and required significant equipment, training, and office space. New simple user-friendly programs have been developed, but to date there remains a paucity of objective evidence comparing these 3D simulations with post-operative outcomes. The aim of this study is to assess the aesthetic similarity between a pre-operative 3D simulation generated using Arbrea breast simulation software and real post-operative outcomes, with a focus on patient satisfaction. Methods: The authors conducted a prospective study of patients requiring breast augmentation. Patients were asked to assess how realistic the simulation was compared to the one-year post-operative result using the authors' grading scale for breast augmentation simulation assessment. Patient satisfaction with the simulations was assessed using a satisfaction visual analogue scale (VAS) ranging from 0 (not at all satisfied) to 10 (very satisfied). Patient satisfaction with the surgical outcome was assessed using the BREAST-Q Augmentation Module. Results: All patients were satisfied with the simulations and with the attained breast volume, with a mean VAS score of 8.2 ± 1.2. The mean simulation time took 90 s on average. The differences between the pre-operative and one-year post-operative values of the three BREAST-Q assessments were found to be statistically significant (p < 0.001). Conclusions: Three-dimensional simulation is becoming increasingly common in pre-operative planning for breast augmentation. The present study aimed to assess the degree of similarity of three-dimensional simulations generated using Arbrea Breast Software and found that the use of the software provided a very satisfying representation for patients undergoing breast augmentation. However, we recommend informing patients that only the volume simulation is extremely accurate. On the other hand, it is necessary to not guarantee an absolute correspondence regarding the breast shape between the simulation and the post-operative result. [ABSTRACT FROM AUTHOR]

Minimally invasive surgery is an important technique used for cytopathological examination. Recently, multiple studies have been conducted on a three-dimensional (3D) puncture simulation model as it can reveal the internal deformation state of the tissue at the micro level. In this study, a viscoelastic constitutive equation suitable for muscle tissue was derived. Additionally, a method was developed to define the fracture characteristics of muscle tissue material during the simulation process. The fracture of the muscle tissue in contact with the puncture needle was simulated using the cohesive zone model and a 3D puncture finite element model was established to analyze the deformation of the muscle tissue. The stress nephogram and reaction force under different parameters were compared and analyzed to study the deformation of the biological soft tissue and guide the actual operation process and reduce pain. [ABSTRACT FROM AUTHOR]

The lateral band-to-band tunneling (L-BTBT) leakage mechanism increases the OFF state current and prevents the junctionless transistor from scaling. The effect of L-BTBT on FIN shaped gate Junctionless field effect transistor(JLFET) with the ground plane (GP) in oxide has been investigated. The proposed device is simulated using 3-D Silvaco TCAD and shows that it can mitigate the L-BTBT and leads to efficient volume depletion which relaxes the requirements of ultra-thin silicon thickness and high workfunction of the gate electrode. The results show significantly reduced OFF-state current and high Ion/Ioff ratio even at scaled gate length beyond 10 nm along with the reduction in drain induced barrier lowering and threshold voltage roll-off. Thus, the proposed device shows better performance at sub-10 nm node. [ABSTRACT FROM AUTHOR]

Background: Surgical training is primarily carried out through observation during assistance or on-site classes, by watching videos as well as by different formats of simulation. The simulation of physical presence in the operating theatre in virtual reality might complement these necessary experiences. A prerequisite is a new education concept for virtual classes that communicates the unique workflows and decision-making paths of surgical health professions (i.e. surgeons, anesthesiologists and surgical assistants) in an authentic and immersive way. For this project, media scientists, designers and surgeons worked together to develop the foundations for new ways of conveying knowledge using virtual reality in surgery. Materials and method: A technical workflow to record and present volumetric videos of surgical interventions in a photorealistic virtual operating room was developed. Situated in the virtual reality demonstrator called VolumetricOR, users can experience and navigate through surgical workflows as if they are physically present. The concept is compared with traditional video-based formats of digital simulation in surgical training. Results: VolumetricOR let trainees experience surgical action and workflows (a) three-dimensionally, (b) from any perspective and (c) in real scale. This improves the linking of theoretical expertise and practical application of knowledge and shifts the learning experience from observation to participation. Discussion: Volumetric training environments allow trainees to acquire procedural knowledge before going to the operating room and could improve the efficiency and quality of the learning and training process for professional staff by communicating techniques and workflows when the possibilities of training on-site are limited. [ABSTRACT FROM AUTHOR]

In today's age of technical and technological development, the market requires many products, with an emphasis not only on price but also on quality. To meet these requirements, new technologies and production processes are constantly being developed. These technologies and processes lead to modernization of equipment, the purpose of which is to increase production efficiency and productivity. The ever-increasing expectations of economic development place demands on labour productivity, accuracy, quality, reliability, and create a large room for application of various transmission systems. These demands may be met by using advanced technologies in combination with upgraded original equipment and mechanisms. The focus of this article is on the mechanisms that work on the principles of bending member, enabling their rapid prototyping. This paper contributes to the topic with design of bending mechanisms and with the subsequent simulation of the functionality and evaluation of the respective results. [ABSTRACT FROM AUTHOR]

Copyright of Wool Textile Journal is the property of National Wool Textile Science & Technology Information Center 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.)

Labyrinth seals are widely employed in the air system of aircraft engines since they reduce the leakages occurring between blades and shrouds, which affect the entropy generation significantly. Excessive leakage flow of the labyrinth may be reduced the efficiency and performance of the engine. This paper proposes the concept of flow-resistance-increasing vortex (FRIV) on the top of the labyrinth that is based on the flow entropy generation mechanism of the stepped labyrinth and the main flow characteristics that lead to entropy generation. A three-dimensional simulation model of the labyrinth structure was established, and the model was compared and verified with the experimental data of the reference. The relative dissipation strength and vorticity distribution of the FRIV were theoretically analyzed. It was confirmed that the dissipative intensity distribution was the same as the vorticity distribution, and the correlation coefficient was larger in the labyrinth tip region. Therefore, a parametric study was conducted on design parameters related to the FRIV, including the teeth inclined angle, tooth crest width, step inclined angle, and other parameters. The results are beneficial for the construction of a stronger FRIV to reduce the leakage. This research is of great significance for the improvement of engine efficiency and for the reduction of fuel consumption in the future. [ABSTRACT FROM AUTHOR]

Emergency management is a fundamental issue in building management. Therefore, this study was established to simulate the required times and movement conditions for user evacuation from Campus Infrastructure Building in a 3D environment. Eight simulations are carried out by a multi-agent evacuation simulator, Pathfinder, considering 100% and 70% users capacity with a combination of random, divide, zone 1 and zone 2 access selection. The users evacuated were handled by the A* algorithm in the steering mode of 3D evacuation simulation. The evacuation flow was investigated with the user density heat map and Fruin’s Level of Service (LOS). This study found the best path planning obtained from the divide access factor and the impact of the user's capacity is relying on total evacuation time. The critical space is caused by the access width fewer than 1.5 m for every floor, and by widening some spaces helped to improve the evacuation flow.

Development of the coordination system requires the dataset because the dataset could provide information around the system that the coordination system can use to make decisions. Therefore, the capability to process and display data-related positions of objects around the robots is necessary. This paper provides a method to predict an object’s position. This method is based on the Indoor Positioning System (IPS) idea and object position estimation with the multi-camera system (i.e., stereo vision). This method needs two input data to estimate the ball position: the input image and the robot’s relative position. The approach adopts simple and easy calculation technics: trigonometry, angle rotations, and linear function. This method was tested on a ROS and Gazebo simulation platform. The experimental result shows that this configuration could estimate the object’s position with Mean Squared Error was 0.383 meters. Besides, R squared distance calibration value is 0.9932, which implies that this system worked very well at estimating an object’s position.

The purpose of the paper is to analyze and simulate the shielding effectiveness (SE) performance of a fiber reinforced cylindrical shell. A matrix model is presented to evaluate the transmitted electromagnetic fields on the axis of cylindrical shell. SE performance of the cylindrical shell is calculated for various parameters such as radius of cylinder, shell thickness and shell conductivity. Also, a 3D model of the cylindrical shell is constructed via Computer Software Technology (CST) program to carry out the analytical results. The analytical calculations and simulations are performed for TM mode excitation. A good agreement is obtained by the comparison of analytical results and CST simulations.

MEMS microphone has a wide range of application prospects in electronic devices such as mobile phones, headphones, and hearing aids due to its small size, low cost, and reliable performance. Research and development of MEMS microphones involves multiple thermo-electro-mechanical couplings among various physical and electrical fields. Unfortunately, there is not an accurate three-dimensional (3D) MEMS microphone simulation platform, which can be applied for the design of chip parameters and packaging characteristics. Herein, based on commercial COMSOL software, we have established a 3D simulation platform for MEMS microphones, which is used to systematically study the influences of geometric structure and physics parameters on the sensitivity and frequency responses of the microphone and consider the influences of packaging characteristics on the performance of the microphone. The simulation results are consistent with those obtained using a lumped element method, which proves the accuracy of the simulation platform. The platform can be used to design and explore new principles or mechanisms of MEMS microphone devices.