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有限元分析技术在膝关节生物力学应用中的特点与优势

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中国组织工程研究 2025年第15期29卷 3253-3261页

作者：郭欢萱康志杰白小龙田晓燕金凤内蒙古医科大学附属医院影像诊断科内蒙古自治区呼和浩特市010010 内蒙古医科大学研究生院内蒙古自治区呼和浩特市010010

背景:有限元分析是一种先进的计算机工程技术,利用数学近似的方法对真实人体进行模拟,可以真实反映膝关节结构内部的生物力学特征,为理解膝关节疾病发病机制、优化手术方案以及开发新型植入材料提供了有效的工具。目的:对膝关节有限元... 详细信息

背景:有限元分析是一种先进的计算机工程技术,利用数学近似的方法对真实人体进行模拟,可以真实反映膝关节结构内部的生物力学特征,为理解膝关节疾病发病机制、优化手术方案以及开发新型植入材料提供了有效的工具。目的:对膝关节有限元模型的建立及其在膝关节疾病研究中的应用进行综述,并展望了未来的发展趋势。方法:第一作者于2024年4月以“Finite Element Analysis,FEA,knee joint,Finite Element Model,Knee Biomechanics,Knee Osteoarthritis,Knee Prosthesis,Knee Ligaments,Meniscus”为英文检索词在PubMed和EI数据库进行检索,以“有限元分析,有限元模型,膝关节,生物力学,骨关节炎,计算模型,膝关节假体,膝关节韧带,半月板”为中文检索词在中国知网和万方数据库进行检索,最终纳入75篇文献进行分析。结果与结论:①有限元分析法利用医学影像数据获得三维人体模型,将复杂的人体关节结构简化为有限且相互连接的单元,通过对模型施加外部载荷,直观地显示膝关节内部的应力分布。②研究者通过有限元分析深入研究膝关节在不同工况下的内部应力和应变分布,可发现膝关节内部载荷分配平衡改变时,关节软骨的过度载荷及部分区域的负荷下降,这种长期异常应力会引起软骨变形和磨损,最终缺失,对于理解生物力学因素如何引起膝关节退行性变至关重要。③有研究通过有限元分析评估膝骨关节炎患者采用太极拳、步态调整等物理治疗方法的效果,结果显示这些治疗方法减少了软骨的过度负荷,为临床治疗提供了科学理论依据。④临床医生通过有限元分析在手术前进行三维重建、数据测量和模拟手术,能够优化手术治疗策略;此外,还可以通过模拟不同假体的力学特征,改进假体的形状、材料和固定方式,减少患者的并发症,提高患者的治疗效果。⑤人工智能与有限元分析相结合使得有限元模型的构建更为精确和易于操作,极大提高了临床医生医疗实践的效率和患者的治疗效果。⑥有限元分析仅是数字化的模拟,与真实物理状态仍存在一定差异。

关键词：膝关节关节软骨半月板生物力学有限元分析有限元模型膝骨关节炎关节置换人工智能综述

Special issue on the 100^(th) anniversary of Xiamen University

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Light(Science & Applications) 2021年第10期10卷 1812-1813页

作者： Junyong kang Minghui Hong Zhongqun tian Engineering Research Center of Micro-nano Optoelectronic Materials and Devices Ministry of EducationFujian Key Laboratory of Semiconductor Materials and ApplicationsCI center for OSEDCollege of Physical Science and Technology361005 XiamenChina Department of Electrical and Computer Engineering National University of Singapore4 Engineering Drive 3117576 SingaporeSingapore State Key Laboratory of Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy MaterialsCollege of Chemistry and Chemical EngineeringXiamen University361005 XiamenChina

This special issue is devoted to the celebration of the century anniversary of Xiamen University(XMU)(6 April 2021)and the establishment of the LSA Editorial Office in Xiamen(3 July 2021),a collection to highlight the recent exciting research works performed in XMU or by XMU alumni,from all aspects of optics and photonics,including basic,applied and engineering research and *** guest editors are three XMU alumni who are active researchers in these areas:Professor Minghui Hong from National University of Singapore,Professor Zhongqun tian and Professor Junyong kang from XMU.

关键词： Xiamen anniversary devoted

Control of fractional chaotic and hyperchaotic systems based on a fractional order controller

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Chinese Physics B 2014年第8期23卷 274-284页

作者： Li tian-Zeng Wang Yu Luo Mao-kang College of Mathematics Sichuan University Chengdu 610065 China Sichuan Province University Key Laboratory of Bridge Non-destruction Detecting and Engineering Computing School of Science Sichuan University of Science and Engineering Zigong 643000 China

We present a new fractional-order controller based on the Lyapunov stability theory and propose a control method which can control fractional chaotic and hyperchaotic systems whether systems are commensurate or incommensurate. The proposed control method is universal, simple, and theoretically rigorous. Numerical simulations are given for several fractional chaotic and hyperchaotic systems to verify the effectiveness and the universality of the proposed control method.

关键词： fractional-order chaotic system chaos control fractional-order controller hyperchaos

Ammonium sulfide-assisted hydrothermal activation of palygorskite for enhanced adsorption of methyl violet

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Journal of Environmental Sciences 2016年第3期28卷 33-43页

作者： Guangyan tian Wenbo Wang Yuru kang Aiqin Wang Center for Eco-material and Green Chemistry Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China University of the Chinese Academy of Sciences Beijing 100049China R&D Center of Xuyi Palygorskite Applied Technology Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesXuyi 211700China

Herein,palygorskite（PAL）was activated via a simple hydrothermal process in the presence of ammonium sulfide,and the effects of activation on the microstructure,physico-chemical feature and adsorption behaviors of PAL were intensively *** hydrothermal process evidently improved the dispersion of PAL crystal bundles,increased surface negative charges and built more active –Si–O-groups served as the new＂adsorption sites＂.The adsorption property of the activated PAL for Methyl Violet（MV）was systematically investigated by optimizing the adsorption variables,including p H,ionic strength,contact time and initial MV *** activated PAL exhibited a superior adsorption capability to the raw PAL for the removal of MV（from 156.05 to 218.11 mg/g）.The kinetics for MV adsorption followed pseudo second-order kinetic models,while the isotherm and thermodynamics results showed that the adsorption pattern well followed the Langmuir *** structure analysis of PAL before and after adsorption demonstrated that electrostatic interaction and chemical association of –X–O-are the prominent driving forces for the adsorption process.

关键词： Palygorskite Hydrothermal Adsorption Methyl violet

Microstructure Evolution of a Cold-rolled 25Cr-7Ni-3Mo-0.2N Duplex Stainless Steel during Two-step Aging Treatments

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Acta Metallurgica Sinica(English Letters) 2013年第5期26卷 517-522页

作者： tian LIANG Xiaoqiang HU Xiuhong kang Dianzhong LI Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

A cold-rolled 25Cr-7Ni-3Mo-0.2N duplex stainless steel（DSS） has been aged in two steps. Firstly, the aging treatment at interval of 50℃ in a temperature range from 900 to 1050℃ was carried out in order to obtain fine grains. Secondly, another aging treatment at 850℃ was performed to reveal the σ-phase precipitation behavior. A detailed microstructure evolution during those two aging steps was observed by the optical microscope（OM）, the scanning electron microscope（SEM）, the electron backscatter difraction（EBSD） and the transmission electron microscope（TEM）. The results revealed that the micro-duplex structure with grain size of lower than 10 μm appeared after the first aging step. However, their grain size was rapidly increased with increasing aging temperature. Meanwhile, the δ → γ and/or δ → γ ＋ σ transformations took place in association with the occurrence of the extensive recovery or a little recrystallization in δ-grains. During the second aging treatment, σ-phase mainly nucleated at δ/γ interfaces and further grew along those interfaces into various morphologies（e.g., butterfly and granule）. A novel precipitation behavior was found in this study that the γ-grain boundaries bulged not only into the δ-grains as usual, but abnormally into the σ-phase precipitates without the prior precipitation of the isolated secondary austenite γ2or another phases.

关键词： Duplex stainless steel Microstructure evolution Sigma phase Aging treatment Micro-duplex structure

A New Way to CCK Performance Analysis under AWGN Channel

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China Communications 2007年第4期4卷 72-78页

作者： tai Nengjian Wu Jie Gou Yanxin tian Yan AF Engn Univ Telecommun Engn Inst Xian 710077 Shaanxi Peoples R China

In this paper,M-ary Quaternary Orthogonal Keying modulation(MQOK) is proposed based on the analysis of Complementary Code Keying(CCK) and Mary Bi-orthogonal Keying(MBOK).Besides,CCK can be defined as a kind of *** analyzing the performance of MQOK on the condition of additive white Gaussian noise(AWGN) channel,new closed-form formulae for CCK modulation are gained. Comparison between the numerical result and the simulation result confirms that these formulae are more accurate and practical to manipulate.

关键词： CCK MQOK AWGN channel Performance analysis

Weak Signal Frequency Detection Based on a Fractional-Order Bistable System

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Chinese Physics Letters 2012年第6期29卷 13-16页

作者： HE Gui-tian LUO Mao-kang Department of Mathematics Sichuan UniversityChengdu 610064

We apply spectral power amplification to quantifying and investigating the phenomenon of stochastic resonance in fractional-order ***,the frequency of the weak mixed signal is detected by a stochastic resonance mechanism together with a power *** corresponding numerical results demonstrate the effectiveness of the proposed methods.

关键词： spectrum methods stochastic

Recent progress in the applications of presynaptic dopaminergic positron emission tomography imaging in parkinsonism

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Neural Regeneration Research 2025年第1期20卷 93-106页

作者： Yujie Yang Xinyi Li Jiaying Lu Jingjie Ge Mingjia Chen Ruixin Yao Mei tian Jian Wang Fengtao Liu Chuantao Zuo Key Laboratory of Arrhythmias Ministry of EducationDepartment of Medical GeneticsShanghai East HospitalSchool of MedicineTongji UniversityShanghaiChina Department of Neurology National Research Center for Aging and MedicineNational Center for Neurological Disordersand State Key Laboratory of Medical NeurobiologyHuashan HospitalFudan UniversityShanghaiChina Department of Nuclear Medicine&PET Center National Center for Neurological Disordersand National Clinical Research Center for Aging and MedicineHuashan HospitalFudan UniversityShanghaiChina International Human Phenome Institutes(Shanghai) ShanghaiChina Human Phenome Institute Fudan UniversityShanghaiChina

Nowadays,presynaptic dopaminergic positron emission tomography,which assesses deficiencies in dopamine synthesis,storage,and transport,is widely utilized for early diagnosis and differential diagnosis of *** review provides a comprehensive summary of the latest developments in the application of presynaptic dopaminergic positron emission tomography imaging in disorders that manifest *** conducted a thorough literature search using reputable databases such as PubMed and Web of *** criteria involved identifying peer-reviewed articles published within the last 5 years,with emphasis on their relevance to clinical *** findings from these studies highlight that presynaptic dopaminergic positron emission tomography has demonstrated potential not only in diagnosing and differentiating various Parkinsonian conditions but also in assessing disease severity and predicting ***,when employed in conjunction with other imaging modalities and advanced analytical methods,presynaptic dopaminergic positron emission tomography has been validated as a reliable in vivo *** validation extends to screening and exploring potential neuropathological mechanisms associated with dopaminergic *** summary,the insights gained from interpreting these studies are crucial for enhancing the effectiveness of preclinical investigations and clinical trials,ultimately advancing toward the goals of neuroregeneration in parkinsonian disorders.

关键词： aromatic amino acid decarboxylase brain imaging dopamine transporter Parkinson’s disease parkinsonism positron emission tomography presynaptic dopaminergic function vesicle monoamine transporter type 2

Raindrop Size Distribution Measurements at High Altitudes in the Northeastern Tibetan Plateau during Summer

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Advances in Atmospheric Sciences 2023年第7期40卷 1244-1256页

作者： Huibang HAN Yuxin ZHANG Jianbing tian Xiaoyan kang Meteorological Disaster Prevention Technology Center in Qinghai Province Xining 810000China Key Laboratory for Disaster Prevention and Mitigation in Qinghai Province Xining 810000China

Characteristics of raindrop size distribution during summer are studied by using the data from six Parsivel disdrometers located in the northeastern Tibetan *** analysis focuses on convective and stratiform precipitation at high altitudes from 2434 m to 4202 *** results show that the contribution of stratiform and convective precipitation with rain rate between 1≤R<5 mm h^(-1) to the total precipitation increases with altitude,and the raindrop scale and number concentration of convective precipitation is larger than that for stratiform *** droplet size spectra of both stratiform and convective precipitation shows a single peak with a peak particle size between 0.31–0.50 mm,and they have essentially the same peak particle size and number concentration at the same *** maximum spectral widths of stratiform clouds are between 4 mm and 5 mm,while those of convective clouds range from 4 mm to 8 *** Gamma distribution is more suitable than the Marshall-Palmer distribution in terms of the actual raindrop spectrum *** stratiform precipitation particles are smaller with higher number concentration,while the opposite is true for the convective precipitation *** convective precipitation particles drop faster than stratiform precipitation particles when the particle size exceeds 2 mm,and the falling velocity of raindrops after standard curve fitting is underestimated during the observation ***,conventional radar estimation methods would underestimate the precipitation in the Northeastern Tibetan Plateau.

关键词： raindrop size distribution precipitation microphysics Northeastern Tibetan Plateau fall velocity