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胫骨内侧应力在跑步运动过程中的计算机仿真分析

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中国组织工程研究 2025年第27期29卷 5802-5809页

作者：孙媛杨晨马运超北京师范大学体育与运动学院北京市100875 山东体育学院运动与健康学院山东省济南市250100 曲阜师范大学体育科学学院山东省曲阜市273100

背景:内侧胫骨应力综合征是困扰跑步者的一种常见的下肢慢性损伤,其损伤机制可能与“肌肉牵引”假说有关,然而这种假说还没有得到完全的证实。目的:使用肌骨仿真系统和有限元分析等方法,考察比目鱼肌、胫骨后肌、趾长屈肌在跑步过程中... 详细信息

背景:内侧胫骨应力综合征是困扰跑步者的一种常见的下肢慢性损伤,其损伤机制可能与“肌肉牵引”假说有关,然而这种假说还没有得到完全的证实。目的:使用肌骨仿真系统和有限元分析等方法,考察比目鱼肌、胫骨后肌、趾长屈肌在跑步过程中的收缩特征是否与跑步时胫骨内侧缘的应力水平存在相关性,从而影响内侧胫骨应力综合征的发生与发展。方法:将6名受试者不同速度跑步时的动作捕捉数据输入Anybody Modeling System骨肌仿真系统,对2.5,3.5,4.5 m/s三种跑步速度情况下的步态支撑期进行逆动力学仿真,将仿真得到的边界条件与有限元模型结合,考察胫骨内侧的应力分布情况。使用偏最小二乘回归方法分析自变量(肌力、弹性势能)与因变量(胫骨应力)之间的相关性。结果与结论:①胫骨应力水平在支撑期(1%-50%)存在速度间的统计学差异(P=0.044,F=3.834,η_(p)^(2)=0.040);②3种速度下,比目鱼肌的肌力与胫骨应力之间的平均相关性最高(r=12.999),其次胫骨后肌肌力与胫骨应力的平均相关性排名第二(r=-10.735),然后依次是趾长屈肌肌力(r=-9.751),胫骨后肌弹性势能(r=8.012),比目鱼肌弹性势能(r=9.076),趾长屈肌弹性势能(r=-4.782);③结果表明,跑步速度的增加,胫骨应力水平随之上升;比目鱼肌的收缩及吸收的弹性势能在跑步过程中的释放对于内侧胫骨应力综合征的发展将产生不可忽略的影响,而胫骨后肌和趾长屈肌的作用被高估了;综合来看,研究支持了“肌肉牵引”假说中比目鱼肌的收缩对内侧胫骨应力综合征发展发挥作用的推论。

关键词：胫骨应力综合征生物力学仿真内侧胫骨应力综合征 anybody modeling system Abaqus 有限元分析

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A core–shell amidoxime electrospun nanofiber affinity membrane for rapid recovery Au(Ⅲ) from water

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Chinese Journal of Chemical Engineering 2022年第2期35卷 424-436页

作者： yang chen Lanying Jiang School of Metallurgy and Environment Central South UniversityChangsha 410083China National Engineering Research Center for Control&Treatment of Heavy Metal Pollution Changsha 410083 China Key Laboratory of Hunan Province for Water Environment and Agriculture Product Safety Changsha 410000China

An affinity membrane was prepared by coaxial electrospinning and amidoxime(AONFA),and it was applied to selectively recovery Au(Ⅲ)from an aqueous *** static adsorption results showed that,when p H at 5,the maximum adsorption capacity of AONFA membrane for Au(Ⅲ)was 509.3 mg·g^(-1).AONFA membrane exhibit much higher affinity and selectivity towards Au(Ⅲ)than other metal *** membrane could be regenerated effectively by mixture solution of thiourea and HCl,and the desorption ratio reached almost 100%after 4 hours *** dead-end filtration results showed that,the membrane utilization efficiency and adsorption capacity can be improved by increasing the flow rate,while increasing the concentration shorted the breakthrough process and had little impact to adsorption *** can flexibly adjust the flow rate and concentration according to the situation to obtain the maximum utilization efficiency of the membrane in filtration *** dynamic adsorption capacity is higher than the static adsorption *** adsorption mechanism for Au(Ⅲ)is electrostatic adsorption and ***,AONFA membrane filtration was demonstrated to be a promising method for continuous recover Au(Ⅲ)from wastewater.

关键词： Coaxial electrospinning Amidoxime Affinity membrane Gold recovery

A Cooperative Fault Detection Approach for Stochastic Multi-Agent Systems Using Maximum Likelihood Estimation Method

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Journal of Systems Science & Complexity 2024年第6期37卷 2451-2465页

作者： yang chen LI Yan chen Qijun School of Electronics and Information Engineering Tongji University

This study addresses the fault detection problem in multi-agent systems(MASs) with additive faults and stochastic uncertainties. The main focus is on enhancing the fault detection capability of each agent through a cooperative fault detection scheme, fostering cooperation between agents in two scenarios. For Gaussian uncertainties, one scheme is developed using the maximum likelihood estimation(MLE) matching expectation maximization(EM) algorithm. Additionally, a novel cooperative fault detection scheme is introduced to handle non-Gaussian uncertainties, where the cooperation mechanism among agents is determined by approximating non-Gaussian uncertainties using the Gaussian mixture model(GMM). The effectiveness and improvements of the proposed cooperative fault detection method are validated through numerical simulations.

关键词： Cooperative fault detection maximum likelihood estimation multi-agent systems

Consortium blockchains-based deep deterministic policy gradient algorithm for optimal electricity trading among households

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The Journal of China Universities of Posts and Telecommunications 2018年第6期25卷 7-20,43页

作者： yang chen College of Electronic and Optical Engineeringand College of Microelectronics Nanjing University of Posts and Telecommunications

To achieve higher energy utilization and lower generation cost for renewable sources(e.g., wind and solar energy), much work has been focused on demand response in smart grid(SG). Nonetheless, most existing studies consider energy trading with utility company which results in high energy loss from high voltage to low voltage and privacy leakage. Besides, there are relatively few researches devoted to electricity scheduling and price optimum among households without a third party. To cope with these issues, a novel deep deterministic policy gradient(DDPG)-based energy trading method with consortium blockchain(DETCB) is introduced. Firstly, in order to enhance system security, executing energy transaction among households is on the basis of consortium blockchain, which leads to not only anonymous trade but also public account. Moreover, the primary target from the aspect of the system is apparently the maximal social welfare, thus exploiting an iterative decision-making method combined with DDPG algorithm by non-profit controllers to obtain optimal trading prices and carry out optimal electricity allocation. To this end, security analysis demonstrates that DETCB contributes to creating a secure, stable and trustful environment. Furthermore, the excellent performance concerning social welfare, algorithm efficiency, and transaction energy sum is shown by numerical results.

关键词： SG DDPG consortium blockchain social welfare non-profit security analysis

A Narrow Band Chandra X-ray Analysis of SNR 3C 391

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Chinese Journal of Astronomy and Astrophysics 2005年第4期5卷 412-418页

作者： yang Su yang chen Department of Astronomy Nanjing University Nanjing 210093

We present narrow-band and equivalent width （EW） images of the thermal composite supernova remnant （SNR） 3C 391 in the X-ray emission lines of Mg, Si and S using the Chandra ACIS Observational data. The EW images reveal the spatial distribution of the emission of the metal species Mg, Si and S in the remnant. They have a clumpy structure similar to that seen in the broadband diffuse emission, suggesting that they are largely of interstellar origin. We find an interesting finger-like feature protruding outside the southwestern radio border of the remnant, somewhat similar to the jet-like Si structure found in the famous SNR Cas A. This feature may possibly be the debris of the jet of ejecta from an asymmetrical supernova explosion of a massive progenitor star.

关键词： ISM: supernova remnants X-rays: ISM - X-rays: individual(3C 391)- ISM: lines and bands

3D Janus plasmonic helical nanoapertures for polarization-encrypted data storage

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Light(Science & Applications) 2019年第1期8卷 788-796页

作者： yang chen Xiaodong yang Jie Gao Department of Mechanical and Aerospace Engineering Missouri University of Science and TechnologyRollaMO 65409USA

Helical structures have attracted considerable attention due to their inherent optical ***,we report a unique type of 3D Janus plasmonic helical nanoaperture with direction-controlled polarization sensitivity,which is simply fabricated via the one-step grayscale focused ion beam milling *** dichroism in transmission of as large as 0.72 is experimentally realized in the forward direction due to the spin-dependent mode coupling process inside the helical ***,in the backward direction,the nanoaperture acquires giant linear dichroism in transmission of up to *** encoding the Janus metasurface with the two nanoaperture enantiomers having specified rotation angles,direction-controlled polarization-encrypted data storage is demonstrated for the first time,where a binary quick-response code image is displayed in the forward direction under the circularly polarized incidence of a specified handedness,while a distinct grayscale image is revealed in the backward direction under linearly polarized illumination with a specified azimuthal *** envision that the proposed Janus helical nanoapertures will provide an appealing platform for a variety of applications,which will range from multifunctional polarization control,enantiomer sensing,data encryption and decryption to optical information processing.

关键词： helical specified backward

ManyInsights: A Visual Analytics Approach to Supporting Effective Insight Management

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Tsinghua Science and Technology 2013年第2期18卷 171-181页

作者： yang chen Jing yang the Department of Computer Science University of North Carolina at CharlotteCharlotte NC 28223 USA

Although significant progress has been made towards effective insight discovery in visual analytics systems, there are few effective approaches for managing the large number of insights generated in visual analytics processes. This paper presents Manylnsights, a multidimensional visual analytics prototype that integrates several novel insight management approaches proposed by the authors in their previous work. These approaches include insight annotation, browsing, retrieval, organization, and association. This paper also reports a long-term case study that evaluated Manylnsights with a domain expert, realistic analytic tasks, and real datasets.

关键词： visual analytics insight management multidimensional visualization

Linear discriminant analysis with worst between-class separation and average within-class compactness

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Frontiers of Computer Science 2014年第5期8卷 785-792页

作者： Leilei yang Songcan chen College of Computer Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Linear discriminant analysis （LDA） is one of the most popular supervised dimensionality reduction （DR） tech- niques and obtains discriminant projections by maximizing the ratio of average-case between-class scatter to average- case within-class scatter. Two recent discriminant analysis algorithms （DAS）, minimal distance maximization （MDM） and worst-case LDA （WLDA）, get projections by optimiz- ing worst-case scatters. In this paper, we develop a new LDA framework called LDA with worst between-class separation and average within-class compactness （WSAC） by maximiz- ing the ratio of worst-case between-class scatter to average- case within-class scatter. This can be achieved by relaxing the trace ratio optimization to a distance metric learning prob- lem. Comparative experiments demonstrate its effectiveness. In addition, DA counterparts using the local geometry of data and the kernel trick can likewise be embedded into our frame- work and be solved in the same way.

关键词： dimensionality reduction linear discriminantanalysis the worst separation the average compactness.

Simulation of the Fate of Faecal Bacteria in Estuarine and Coastal Waters Based on A Fractionated Sediment Transport Model

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China Ocean Engineering 2017年第4期31卷 389-395页

作者： yang chen LIU Ying College of Petroleum Engineering China University of Petroleum Beijing 102249 China China Institute of Water Resources and Hydropower Research Beijing 100038 China Research Center on Flood & Drought Disaster Reduction of the Ministry of Water Resources Beijing 100038 China

A two-dimensional depth-integrated numerical model is refined in this paper to simulate the hydrodynamics, graded sediment transport process and the fate of faecal bacteria in estuarine and coastal waters. The sediment mixture is divided into several fractions according to the grain size. A bed evolution model is adopted to simulate the processes of the bed elevation change and sediment grain size sorting. The faecal bacteria transport equation includes enhanced source and sink terms to represent bacterial kinetic transformation and disappearance or reappearance due to sediment deposition or re-suspension. A novel partition ratio and dynamic decay rates of faecal bacteria are adopted in the numerical model. The model has been applied to the turbid water environment in the Bristol Channel and Severn estuary, UK. The predictions by the present model are compared with field data and those by non-fractionated model.

关键词： bed evolution decay rate esmarine and coastal water faecal bacteria fractionated model sediment Wansport