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Regional Variations in Trabecular Morphological Features of Femoral Head of Patients with Proximal Femoral Fractures

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Journal of Bionic Engineering 2015年第2期12卷 294-303页

作者： linwei lv Guangwei Meng He Gong Dong Zhu Jiazi Gao Meisheng Zhao School of Mechanical Science and Engineering Jilin University Changchun 130022 China School of Mechanical Engineering Tianjin University of Technology Tianjin 300384 China Department of Orthopedic Surgery the First Clinical Hospital of Jilin University Changchun 130021 China Department of Cataract Eye Hospital of the Second Clinical Hospital of Jilin University Changchun 130000 China

The regional microstructural variations in femoral head from proximal femoral fracture patients were investigated. Mi- cro-CT scanning was performed on seven femoral heads from proximal femoral fracture patients. Each femoral head was divided into three regions according to the trabecular orientation from the fovea of femoral head to the femoral neck. Eight three-dimensional trabecular cube models were reconstructed from each region. A total of 154 trabecular cubic models were reconstructed because the corresponding areas for 14 cubic models were damaged during the surgeries. Eight trabecular mor- phological parameters were measured and analyzed, namely, trabecular thickness （***）, trabecular separation （***）, spe- cific bone surface （BS/BV）, bone volum在不 fraction （BV/TV）, structural model index （SMI）, degree of anisotropy （DA）, trabecular pattern factor （***）, and trabecular number （Tb.N）. Bivariate correlation analyses were performed for all mor- phological parameters. One-way ANOVA tests were performed to analyze the differences of each parameter among three re- gions. Post-hoc multiple comparisons （Student-Newman-Keuls method） were performed to analyze the morphological differ- ence between two regions. Trabecular bone of proximal femoral fracture patients significantly degenerated in all regions of femoral heads. BV/TV was statistically correlated with ***, ***, BS/BV, ***, and Tb.N （p 〈 0.05）. Statistical differences in morphological parameters were observed between regions （p 〈 0.05）. The trabecular strength in the middle regions was significantly higher than that in other regions because of the relationships between morphological parameters and mechanical parameters. Trabeculae in the medial region were more uniform and stable along each direction than those in the lateral region. Most trabeculae in the lateral region only grew along the weight-bearing direction, and those along the other directions de- generated significantly. This study provide

关键词： femoral head trabeculae proximal femur fracture morphological parameter micro-CT

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The relationship between orthopedic clinical imaging and bone strength prediction

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Medicine in Novel Technology and Devices 2021年第1期9卷 9-17页

作者： He Gong Meng Zhang Shaowei Jia linwei lv Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education Beijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang UniversityBeijingChina Department of Engineering Mechanics Nanling CampusJilin UniversityChangchun130025China Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical EngineeringTianjin University of TechnologyTianjin300384China

Pathologic fracture is caused by bone diseases,which is common in middle-aged and elderly *** bone strength is the leading contributor to this type of ***,accurately quantifying bone strength could help clinicians assess individualized fracture risk and develop therapeutic *** clinical imaging including dual X-ray absorptiometry(DXA),computed tomography(CT),and magnetic resonance imaging(MRI)has been an important tool to obtain radiology images of bone,which could be further used for noninvasive assessment of bone strength and related fracture *** the development of biomechanics and computer technology,the combination of finite element analysis with orthopedic imaging is the most advanced method for noninvasive prediction of bone strength in *** this review,an overview is provided for the commonly noninvasive methods based on the radiology images(i.e.,DXA,CT,and MRI)to predict bone strength,which may improve the understanding of the relationship between orthopedic clinical imaging and biomechanics.

关键词： Orthopedic clinical imaging Biomechanics Bone strength Finite element analysis

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ABAQUS二次开发在骨重建仿真中的应用

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天津理工大学学报 2021年第5期37卷 39-44页

作者：井野吕林蔚宋阳张春秋天津理工大学天津市先进机电系统设计与智能控制重点实验室天津300384 天津理工大学机电工程国家级实验教学示范中心天津300384

本研究的目的是利用ABAQUS二次开发环境,将基于应变能密度准则的骨自优化理论,编写成骨重建仿真算法。可以提取仿真模拟的密度分布数据作为场变量以云纹图的形式显示出来。通过计算骨组织密度的变化趋势分析骨重建过程。建立二维悬臂梁... 详细信息

本研究的目的是利用ABAQUS二次开发环境,将基于应变能密度准则的骨自优化理论,编写成骨重建仿真算法。可以提取仿真模拟的密度分布数据作为场变量以云纹图的形式显示出来。通过计算骨组织密度的变化趋势分析骨重建过程。建立二维悬臂梁模型,进行200步迭代计算。结果显示密度分布呈现出桁架结构,验证了基于ABAQUS二次开发环境的骨重建算法的正确性。进一步建立股骨近端模型,模拟其正常站立的受力情况。根据有限元分析得到的骨密度分布可以反映出股骨内部骨组织的主要结构特征。本研究基于Python语法设计骨重建迭代算法,可以方便提取并输出密度及其他力学参数作为场变量。

关键词： ABAQUS二次开发骨重建算法自优化理论股骨近端

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Relationships between femoral strength evaluated by nonlinear finite element analysis and BMD,material distribution and geometric morphology

Relationships between femoral strength evaluated by nonlinea...

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第九届全国生物力学学术会议

作者： He Gong~(1*),linwei lv~1,Rui Zhang~1,Dong Zhu~3,Ming Zhang~2(1.Department of Engineering Mechanics,Jilin University,Changchun 130025,P.R.China 2.Department of Health Technology and Informatics,The Hong Kong Polytechnic University,Hong Kong,China 3.Department of Orthopedic Surgery,No.1 Hospital,Jilin University,Changchun 130021,China)

Precisely quantifying the strength of the proximal femur and accurately assessing hip fracture risk would enable those at high risk to be identified so that preventive interventions could be *** of better measures of femoral strength using the clinically available information is an important research and clinical *** purposes of this study were:to develop subject-specitic QCT image-based finite element models to predict the strength of proximal

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Identification and control of Sandwich system with backlash

Identification and control of Sandwich system with backlash

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第36届中国控制会议

作者： linwei Li Xuemei Ren Minlin Wang Yongfeng lv School of Automation Beijing Institute of Technology

ISBN: (纸本)9781538629185

The identification and control of Sandwich systems are surveyed for the systems which involve backlash nonlinearity. The focus is made on the way of constructing the identification model and the convergence rate of the identification algorithm. Based on a parameterization of backlash, the Sandwich system with backlash is constructed as a regression model in which the backlash parameter and linear subsystems parameters are separated by using the key-term separation principle. In order to improve the convergence rate, a multi-innovation least squares algorithm is applied to identify the parameter of the regression equation by modifying the scalar single innovation as multi-innovation matrix. Finally, a traditional PID controller achieves a reference signal tracking based on the result of the parameter estimation.

关键词： Multi-innovation identification PID Sandwich system Backlash the key-term separation principle

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Nash Tracking Controls of Multi-input Nonzero-Sum Game System with Reinforcement Learning

Nash Tracking Controls of Multi-input Nonzero-Sum Game Syste...

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第37届中国控制会议

作者： Yongfeng lv Xuemei Ren linwei Li Jing Na School of Automation Beijing Institute of Technology Faculty of Mechanical & Electrical Engineering Kunming University of Science & Technology

This paper addresses Nash optimal tracking controls of the unknown multi-player game system with a reinforcement learning scheme. We propose a single-layer neural network to approximate the unknown multi-player system, where the system can be accurately identified. It is then used to calculate the Nash tracking controls, which are designed by two parts: the steady-state control and the optimal feedback tracking control. The optimal feedback tracking controls are obtained by using the HJB equation with the reinforcement learning scheme. The convergences of the NN weights and the approximated optimal controls are analyzed. Finally, a simulation is provided to illustrate the effectiveness of the methods in this paper.

关键词： Reinforcement learning nonzero-sum game neural networks Nash equilibrium multi-input system

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Parameter estimation for multivariable Hammerstein systems based on the decomposition technique

Parameter estimation for multivariable Hammerstein systems b...

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第37届中国控制会议

作者： linwei Li Xuemei Ren Yongfeng lv Minlin Wang School of Automation Beijing Institute of Technology

The focus of this paper is the parameter identification of multivariable Hammerstein controlled autoregressive moving average（for short,CARMA） *** on the internal relationship between the nonlinear submodel and linear subsystem,the multivariable nonlinear CARMA systems are converted into a special identification model which includes the bilinear parameter vector and the other parameter *** order to address the above bilinear parameter vector,we construct two the corresponding estimation models in which each identification model is linear to the corresponding parameter vector by using matrix transformation,and developed an adaptive estimation approach to interactively identify the parameter vectors through the usage of the hierarchical identification principle and filtering *** conditions of convergence are discussed through the usage of the martingale *** comparative simulation results show that the presented approach produces higher estimation accuracy and faster convergence rate than some publishing identification methods.

关键词： Parameter identification multivariable nonlinear systems filtering technique hierarchical identification idea

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Relationships between femoral strength evaluated by nonlinear finite element analysis and BMD,material distribution and geometric morphology

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医用生物力学 2009年第S1期24卷 66-66页

作者： He Gong1,linwei lv1,Rui Zhang1,Dong Zhu3,Ming Zhang2(1.Department of Engineering Mechanics,Jilin University,Changchun 130025,P.R.China 2.Department of Health Technology and Informatics,The Hong Kong Polytechnic University,Hong Kong,China 3.Department of Orthopedic Surgery,No.1 Hospital,Jilin University,Changchun 130021,China)

关键词： BMD Relationships between femoral strength evaluated by nonlinear finite element analysis and BMD,material distribution and geometric morphology FEA

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公立医疗机构法人治理的委托代理悖论与化解逻辑

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浙江学刊 2020年第2期 97-105页

作者：吴素雄杨华吕鸿强俞林伟温州医科大学公共卫生与管理学院温州325035 浙江中医药大学马克思主义学院

公立医疗机构法人治理的目的是通过委托代理的关系建构来实现国家资产所有权与管理权的分离以增强其经营自主性,但在这一关系所形成的治理结构中存在着由自利行为与信息不对称所诱致的双向道德风险与监督失效的可能,这一代理困境源于委... 详细信息

公立医疗机构法人治理的目的是通过委托代理的关系建构来实现国家资产所有权与管理权的分离以增强其经营自主性,但在这一关系所形成的治理结构中存在着由自利行为与信息不对称所诱致的双向道德风险与监督失效的可能,这一代理困境源于委托代理环闭中责任次序的环节存在漏洞,这需要通过建构国家层面的民主政治、家庭医生的信息代理机制、医保参与的利益制衡机制以及公立医疗机构的绩效评价体系来化解。但在这一过程中,国家需要通过政策工具引导利益关联方的参与来防止治理主体间的共谋行为。

关键词：公立医疗机构法人治理委托代理

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分级诊疗背景下流动人口基层首诊意愿及影响因素研究

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中国医院 2023年第5期27卷 51-54页

作者：韩辰俞林伟金杰克吕一军温州医科大学公共卫生与管理学院浙江省温州市325035

目的:分析流动人口基层首诊意愿现状,探讨其中的影响因素,为推进分级诊疗制度、引导流动人口形成科学合理的就医秩序提供政策建议和思路。方法:基于2017年全国流动人口动态监测中64 028位最近1次患病(负伤)的流动人口,利用SPSS 22.0统... 详细信息

目的:分析流动人口基层首诊意愿现状,探讨其中的影响因素,为推进分级诊疗制度、引导流动人口形成科学合理的就医秩序提供政策建议和思路。方法:基于2017年全国流动人口动态监测中64 028位最近1次患病(负伤)的流动人口,利用SPSS 22.0统计软件分析流动人口的首诊意愿和影响因素。结果:64 028名流动人口中,只有12 675人选择基层首诊。二元logistic回归结果显示:年龄越年长、随迁家庭人数越多、跨省流动、健康状态越好、有落户意愿、听说过“国家基本公共卫生服务项目”、建立了健康档案、接受过健康教育及居住地到最近医疗服务机构所需时间≤15 min的流动人口更愿意选择基层首诊。结论:流动人口基层就诊意愿较低,表明分级诊疗制度在流动人口群体中并未得到有效认可;不同特征流动人口就医选择存在差异性;年龄、文化程度、流动范围、同住家庭人数、健康状态、是否听说过“国家基本公共卫生服务项目”、是否建立了居民健康档案、是否接受过健康教育、有无落户意愿、到达最近的医疗服务机构的时间及是否持有本地医保是流动人口选择基层医疗卫生机构首诊的主要影响因素。

关键词：分级诊疗流动人口首诊意愿影响因素

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