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Journal of Huazhong University of Science and Technology(Medical Sciences) 2013年第5期33卷 775-779页

作者：黄政陈智 Key Laboratory for Oral Biomedicine of Ministry of Education School and Hospital of Stomatology Wuhan University

This study describes the details of how to construct a three-dimensional （3D） finite element model of a maxillary first premolar tooth based on micro-CT data acquisition technique, MIMICS soft- ware and ANSYS software. The tooth was scanned by micro-CT, in which 1295 slices were obtained and then 648 slices were selected for modeling. The 3D surface mesh models of enamel and dentin were created by MIMICS （STL file）. The solid mesh model was constructed by ANSYS. After the material properties and boundary conditions were set, a loading analysis was performed to demonstrate the ap- plicableness of the resulting model. The first and third principal stresses were then evaluated. The re- suits showed that the number of nodes and elements of the finite element model were 56 618 and 311801, respectively. The geometric form of the model was highly consistent with that of the true tooth, and the deviation between them was ~）.28%. The loading analysis revealed the typical stress patterns in the contour map. The maximum compressive stress existed in the contact points and the maximum tensile stress existed in the deep fissure between the two cusps. It is concluded that by using the micro-CT and highly integrated software, construction of the 3D finite element model with high quality will not be difficult for clinical researchers.

关键词： three-dimensional finite element micro-CT premolar MIMICS ANSYS

three-fin acetabular prosthesis for superior acetabular bone defects： a three-dimensional finite element analysis

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Chinese Medical Journal 2012年第5期125卷 901-905页

作者： LIU Yu-zeng HAI Yong ZHAO Hui Department of Orthopedics Beijing Chaoyang HospitalCapital Medical UniversityBeijing 100020China

Background Given that three-dimensional finite element models have been successfully used to analyze biomechanics in orthopedics-related research, this study aimed to establish a finite element model of the pelvic bone and three-fin acetabular component and evaluate biomechanical changes in this model after implantation of a three-fin acetabular prosthesis in a superior segmental bone defect of the acetabulum.

关键词： three-dimensional finite element segmental bone defect of the acetabulum prosthesis design

three dimensional K-Tz stress fields around the embedded center elliptical crack front in elastic plates

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Acta Mechanica Sinica 2006年第2期22卷 148-155页

作者： Junhua Zhao Wanlin Guo Chongmin She Bo Meng eng Institute of Nano Science Nanjing University of Aeronautics Astronautics Nanjing 210016 China

Through detailed three-dimensional （3D） finite element （FE） calculations, the out-of-plane constraints Tz along embedded center-elliptical cracks in mode I elastic plates are studied. The distributions of Tz are obtained near the crack front with aspect ratios （a/c） of 0.2, 0.4, 0.5, 0.6, 0.8 and 1.0. Tz decreases from an approximate value of Poisson ratio v at the crack tip to zero with increasing normalized radial distances （r/a） in the normal plane of the crack front line, and increases gradually when the elliptical parameter angle φ changes from 0° to 90°at the same r/a. With a/c rising to 1.0, Tz is getting nearly independent of φ and is only related to r/a. Based on the present FE calculations for Tz, empirical formulas for Tz are obtained to describe the 3D distribution of Tz for embedded center-elliptical cracks using the least squares method in the range of 0.2 ≤ a/c ≤ 1.0. These Tz results together with the corresponding stress intensity factor K are well suitable for the analysis of the 3D embedded centerelliptical crack from field, and a two-parameter K-Tz principle is proposed.

关键词： three-dimensional finite element Out-of-plane constraint Tz Embedded elliptical crack Stress intensity factor T-Stress Stress field

Influences of the heterogeneity of viscoelastic medium on postseismic deformation of the 2008 M_(W) 7.9 Wenchuan earthquake

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Geodesy and Geodynamics 2022年第1期13卷 1-10页

作者： Feng Li Peng Zhai Jinshui Huang Hongbo Tan Mengcheng National Geophysical Observatory School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei230026China Earthquake Administration of Jiangsu Province Nanjing210014China CAS Center for Excellence in Comparative Planetology Hefei230026China

The study of postseismic deformation is important for constraining the viscoelastic properties of the Earth and inverting the post-earthquake *** levelling survey revealed that the area near Bei-chuan elevated 5.3 cm about two years after the M_(W) 7.9 Wenchuan earthquake(05/12/2008),during which the area underwent significant downward *** GPS horizontal displacements showed a non-monotonic variation after the Wenchuan *** this study,a 3-D viscoelastic finite element model is employed to simulate the coseismic and postseismic deformation of the Wenchuan *** numerical simulations show that the lateral heterogeneity across the Longmenshan fault plays an important role in the postseismic *** results reveal that the coseismic defor-mation is not sensitive to the horizontal heterogeneity,but the postseismic deformation is sensitive to *** postseismic deformation of the horizontally heterogeneous model is generally consistent with the observations of all geodetic surveys,such as GPS,InSAR and levelling,but not for the horizontally homogenous *** also find that the non-monotonous variation of the postseismic deformation of the Wenchuan earthquake could be explained by a viscoelastic relaxation model with lateral heterogeneous medium across the Longmenshan fault.

关键词： M_(W)7.9 Wenchuan earthquake Postseismic deformation Viscoelastic relaxation Horizontal heterogeneity three-dimensional finite element

Dynamic response of concrete pavement structure with asphalt isolating layer under moving loads

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Journal of Traffic and Transportation Engineering(English Edition) 2014年第6期1卷 439-447页

作者： Jianmin Wu Jiaping Liang Sanjeev Adhikari Key Laboratory for Special Area Highway Engineering of Ministry of Education Chang'an University Guangxi Hualan Design & Consulting Group Department of Applied Engineering and Technology Morehead State UniversityMoreheadKentuckyUSA

A three-dimensional finite element model （3D FEM） is built using ABAQUS to analyze the dynamic response of a concrete pavement structure with an asphalt isolating layer under moving loads. The 3D model is prepared and validated in the state of no asphalt isolating layer. Stress and deflection at the critical load position are calculated by changing thickness, modulus of isolating layer and the combination between the isolating layer and concrete slab. Analysis result shows that the stress and deflection of the concrete slab increase with the increase of thickness. The stress and deflection of the concrete slab decrease with the increase of combination between the isolating layer and concrete slab. The influence of changing the isolating layer modulus to the stress and deflection of the concrete slab is not significant. From the results, asphalt isolating layer design is suggested in concrete pavement.

关键词： concrete pavement asphalt isolating layer moving loads three-dimensional finite element

Influence of Perforation on Formation Fracturing Pressure

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Petroleum Science 2004年第3期1卷 56-61页

作者：张广清陈勉王学双赵冲石油大学石油天然气工程学院中国北京昌平102249 吉林油田钻井服务公司中国吉林省松原市138001 大港油田钻井工程公司中国天津大港300280

Hydraulic fracturing treatments of oil wells are greatly affected by the perforation parameters selected. The three-dimensional finite element model together with the tensile criterion of rock materials is employed to systematically investigate the influence of perforation parameters, such as perforation density, perforation orientation, perforation diameter, and perforation length as well as wellbore ellipticity, in vertical wells on the formation fracturing pressure. Based on a six-month simulation research in the University of Petroleum, China, several conclusions are drawn for the first time. Perforation density and perforation orientation angle are the most important parameters controlling the formation fracturing pressure. As the perforation density increases, the fracturing pressure decreases, not linearly but progressively. The fracturing pressure increases with the perforation orientation angle only when the angle is less than 45 degrees, and the relationship becomes very flat when the angle is 45 degrees. However, with regards to the perforation diameter and perforation length, their influences are much slighter. The wellbore ellipticity has a significant effect on the formation fracturing pressure. It is obvious that fracturing pressure increases linearly with the ellipticity of the wellbore.

关键词： Fracturing pressure three-dimensional finite element perforation parameter

Dynamic finite element Analysis of RCC Gravity Dam

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Dynamic Finite Element Analysis of RCC Gravity Dam

Research on the coupling heart electric field using passive human body detection system

The 2011 International Conference on Smart Materials and Nanotechnology in Engineering (ICSMCE2011)

作者： Xiaoyan Zhang Ze Li Liang Wu School of Electrical Power Engineering of Kunming University of Science and Technology Engineering Mechanics Department of Kunming University of Science and Technology

Dynamic finite element analysis for a RCC gravity dam is implemented by using response spectrum method in this paperFirstly, three-dimensional finite element model is established, and then the subspace iterative method is used in the modal analysis of the gravity damThe natural vibration frequencies, the natural vibration period and modes are obtainedThe response spectrum method is employed to implement dynamic analysis of the gravity damAt last, the combinations of both the static and dynamic stress are made with the principle for extreme strength condition, seismic dynamic response of the dam is investigated.

关键词： three-dimensional finite element response spectrum method RCC gravity dam characteristic of natural vibration

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Research on the coupling heart electric field using passive ...

Effect of 3D anchorage attachment on the alleviating tipping/extrusion of premolars for en-mass distalization of maxillary molars with clear aligners:A finite element study

Measurement Touch the World——IEEE 2011 10th International Conference on Electronic Measurement & Instruments(ICEMI’2011)

作者： Zhang Yan Xu Lixin State Key Laboratory of Mechatronics Engineering and Control Beijing Institute of TechnologyBeijing P.R.China

An analysis of the coupling heart electric field is a pivotal step in the human body detection system which target for the heart coupling electric field between the operator and the detected living *** this paper,the double-human heart coupling electric field is discussed and the three-dimensional finite element method is used to analytically solve that ***,we described the principle of the single human cardiact electric dipole equal ***,the double-human coupling heart electric field is ***,the three-dimensional finite element method is used for simulating and calculating the coupling heart electric *** three different typical coupling heart electric fields are shown in the *** conclusion of this paper is the most significant studies of the passive human body detection technique.

关键词： human body detection system heart electric dipole coupling heart electric field three-dimensional finite element

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Medicine in Novel Technology and Devices 2023年第2期18卷 272-280页

作者： Lurong Jia Chunjuan Wang Yao He Chao Wang Antonio Apicella Jinlin Song Yubo Fan Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences ChongqingChina Stomatological Hospital of Chongqing Medical University ChongqingChina Key Laboratory of Biomechanics and Mechanobiology Ministry of EducationBeijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringSchool of Engineering MedicineBeihang UniversityBeijingChina Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education ChongqingChina Polytechnique School of Engineering and Base Science University of CampaniaItaly

This study aimed to explore the optimal invisible orthodontic force system during the en-mass distalization of two maxillary molars to minimize the side effect of anchorage loss by changing the direction of the application of the orthodontic force system.A high bio-fidelity 3D finite element model including maxilla,periodontal ligament,dentition,clear aligner,3D anchorage attachment and mini-implant was *** lengths of lateral hooks of 3D-printed anchorage attachments and mini-implant positions into the palatal alveolus were considered.A 200 g distal force was applied to the lateral hooks of different horizontal lengths(3.26 mm,6.52 mm and 9.78 mm)with the mini-implant as the application *** ABAQUS software,orthodontic tooth movements under 12 different clinical treatment designs were analyzed and *** 3D anchorage attachment enhanced the anchorage of anterior teeth and alleviated the tipping/extrusion of *** contrast to without clear aligners,length of the lateral hook had a negligible effect on both mesial tipping and buccal tipping with clear aligners,which could then be *** change in mesial tipping was less and nearly remained constant despite of the different heights of the *** 3D anchorage attachment assisted clear aligner can avoid the side effects of anterior tooth proclination caused by insufficient *** length of the lateral hook,and height of the mini-implant in this invisible orthodontic force system hardly affects the tooth movement of anchorage *** aligners can effectively control the rotation and tipping of anchorage units caused by 3D anchorage attachment.

关键词： Clear aligner Orthodontics 3D printing three-dimensional finite element Attachments Reinforced anchorage