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Distributed order estimation for continuous-time stochastic systems

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Control Theory and Technology 2024年第3期22卷 406-418页

作者： Xinghua Zhu zhixin liu Xiaoming Hu Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100190China Department of Mathematics KTH Royal Institute of TechnologyStockholm 10044Sweden

In this paper,we investigate the distributed estimation problem of continuous-time stochastic dynamic systems over sensor networks when both the system order and parameters are *** propose a local information criterion(LIC)based on the L_(0)penalty *** minimizing LIC at the diffusion time instant and utilizing the continuous-time diffusion least squares algorithm,we obtain a distributed estimation algorithm to simultaneously estimate the unknown order and the parameters of the *** dealing with the effect of the system noises and the coupling relationship between estimation of system orders and parameters,we establish the almost sure convergence results of the proposed distributed estimation ***,we give a simulation example to verify the effectiveness of the distributed algorithm in estimating the system order and parameters.

关键词： Stochastic differential equations Sensor networks Distributed order estimation Cooperative excitation condition.Convergence

Multivariate chemical analysis:From sensors to sensor arrays

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Chinese Chemical Letters 2024年第7期35卷 14-24页

作者： Xueling Yu Lixing Fu Tong Wang zhixin liu Na Niu Ligang Chen College of Chemistry Chemical Engineering and Resource UtilizationKey Laboratory of Forest Plant EcologyNortheast Forestry UniversityHarbin 150040China

Chemical sensor arrays can obtain more comprehensive analyte information through high-dimensional *** is of great significance in the analysis of multi-component complex *** review summarizes the development and status of chemical sensor *** focused on the design of chemical sensor arrays based on various sensing *** addition,several pattern recognition methods in chemometrics are *** applications of chemical sensor arrays in food monitoring,medical diagnosis,and environmental monitoring are *** on the analysis of the limitations of current sensor array technology,the direction of the array is also *** review aims to help the broad readership understand the research state of chemical sensor arrays and their development prospects.

关键词： Chemical sensor arrays Sensing materials Pattern recognition methods Analytical application

Hydrothermal synthesis of polyimide-linked covalent organic frameworks towards ultrafast and stable cathodic sodium storage

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Science China Chemistry 2024年第4期67卷 1300-1310页

作者： Xiya Yang Lei Gong zhixin liu Qianjun Zhi Baoqiu Yu Xin Chen Kang Wang Xiaofeng Li Dongdong Qi Jianzhuang Jiang Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline MaterialsDepartment of Chemistry and Chemical EngineeringSchool of Chemistry and Biological EngineeringUniversity of Science and Technology BeijingBeijing 100083China State Key Laboratory of Organic-Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Redox-active organic materials are capturing growing attention as cathode materials for sustainable alkaline metal ion ***,the storage of Na+in most organic materials-based cathodes is plagued by low capacity and unsatisfying rate performance due to their low active site densities and limited exposed active ***,two polyimide-linked covalent organic frameworks(COFs),namely HATN-PD-COF and HATN-TAB-COF,were fabricated from hydrothermal synthesis with redoxactive triphenylene-2,3,6,7,10,11-hexacarboxylic acid and aromatic amines as starting *** X-ray diffraction and electron microscopy analysis indicate the high crystalline nature of these COFs with AA stacking configuration and orderly mesoporous tunnel.N_(2) sorption measurement discloses the permanent porosity of these two COFs with a Brunauer-EmmettTeller surface area of 1,065-1,200 m^(2)g^(-1)and a large pore size of 2.0-3.1 *** intermittent titration technique and density functional theory calculations reveal the facile Na+ion diffusion along the mesoporous tunnel of these COFs with a small energy barrier of 0.13-0.40 e *** particular,the as-prepared COFs based-cathodes show ultrafast and stable Na+storage associated with their conjugated electronic structure,highly ordered mesoporous tunnel,robust structure,and redox-active C=N/C=O-rich framework as exemplified by the high reversible capacity of 210 m A h g^(-1)at 200 m A g^(-1),record-high rate performance(195 m A h g^(-1)at a high current density of 10,000 m A g^(-1))among organic electrodes and the capacity retention of nearly 91%at 10,000 m A g^(-1)after 7,000 cycles for HATN-PD-COF.

关键词： covalent organic framework sodium ion battery cathode high rate organic electrode

Depletion of anti-CD47mAb in plasma by genetically modified cells for pre-transfusion testing

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Genes & Diseases 2024年第5期11卷 102-104页

作者： Fei Wang Wenting Wang Xiaoshuang Wu zhixin liu Yafen Wang Rong Zhang Shunli Gu Qunxing An Yaozhen Chen Xingbin Hu Department of Transfusion Medicine Xijing HospitalFourth Military Medical UniversityXi’anShaanxi 710032China Xi’an Medical University Xi’anShaanxi 710021China

Allogeneic red blood cell(RBC)transfusion is commonly performed in medical practice because of its efficacy and low-risk ***,pre-transfusion tests are susceptible to monoclonal antibody(mAb)interference.1 Currently,mAb therapies are being developed to treat many diseases,such as ***,certain mAbs,such as anti-CD38mAb and anti-CD47mAb,can bind to RBC membranes;this binding interferes with pre-transfusion tests.2 CD47 has gained considerable attention in recent years because of its potential as a therapeutic target for hematologic malignancies and solid tumors.3 The binding of anti-CD47mAb to RBCs may lead to false-positive results in pan-agglutination tests and cause delays and risks in establishing compatible RBCs for transfusion.

关键词： CD47 transfusion diseases

膝关节置换术围手术期国际功能、残疾和健康分类核心分类组合的信效度评价

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中国心理卫生杂志 2024年第9期38卷 787-795页

作者：刘芷忻王翠王宁华北京大学医学部医学技术研究院北京100191 北京大学第一医院康复医学科北京100034

目的:初步评价综合版膝关节置换术围手术期国际功能、残疾和健康分类(ICF)核心分类组合的效度和信度。方法:招募诊断为膝骨关节炎并接受膝关节置换术的患者41名,进行效标效度、内部一致性、组间信度和组内信度研究。以西大略和麦克马斯... 详细信息

目的:初步评价综合版膝关节置换术围手术期国际功能、残疾和健康分类(ICF)核心分类组合的效度和信度。方法:招募诊断为膝骨关节炎并接受膝关节置换术的患者41名,进行效标效度、内部一致性、组间信度和组内信度研究。以西大略和麦克马斯特大学骨关节炎指数评分(WOMAC)、SF-36健康调查量表(SF-36)、焦虑自评量表(SAS)和抑郁自评量表(SDS)为效标工具。结果:身体结构与功能、活动和参与维度与WOMAC总分及疼痛、困难程度得分正相关(ICC=0.59~0.92),与SF-36多项得分正相关(ICC=0.46~0.89)。条目b130、b134、b152、d230、d240得分与SAS得分正相关(ICC=0.41~0.73),条目b530得分与SDS得分正相关(ICC=0.47),均P<0.05。身体结构与功能、活动和参与、环境因素维度的Cronbachα分别为0.93、0.93、0.53。所有条目的组间信度(ICC)为0.44~0.99;组内信度(ICC)为0.66~0.97。结论:综合版膝关节置换术围手术期ICF核心分类组合具有较好的效度和信度。

关键词：膝关节置换术围手术期 ICF核心分类组合效度信度

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中外优秀男子高尔夫球选手一号木杆下杆技术动作分析与诊断

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体育科技 2024年第2期45卷 26-29页

作者：刘智鑫厦门大学嘉庚学院福建漳州363105

【目的和方法】运用Simi Motion三维动作捕捉分析系统对中外优秀男子高尔夫球职业选手一号木杆挥杆进行定量和定性研究,解码下杆动作技术特征,总结技术规律和特征背后的理论支撑。【结果】我国选手平均最大杆头速度、平均球速及击球效... 详细信息

【目的和方法】运用Simi Motion三维动作捕捉分析系统对中外优秀男子高尔夫球职业选手一号木杆挥杆进行定量和定性研究,解码下杆动作技术特征,总结技术规律和特征背后的理论支撑。【结果】我国选手平均最大杆头速度、平均球速及击球效率均低于国外选手;击球阶段用时与杆头最大速度、球速呈显著性负相关(P<0.05),平均杆数与击球距离、击球阶段用时呈显著性正相关(P<0.05),击球距离与球速呈显著性正相关(P<0.05),球速与平均杆数呈显著性负相关(P<0.05);下杆技术重心位移变化中,通过讨论各坐标轴位移变化增量发现,加速旋转阶段和击球阶段组间差异明显。【结论】我国选手可适当延长加速旋转阶段用时,同时适当缩短击球阶段用时,杆头最大速度易产生,从而影响球速,以此提高我国选手的击球效率;我国选手在加速旋转阶段X轴重心位移太大,Y轴重心位移变化不够,致使髋部侧移不明显和下杆系统转动的稳定性被破坏,不利于击球效果,故下杆髋部侧移和旋转加速动作可优化。

关键词：男子高尔夫球选手下杆技术分析

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基于STM32的无线充电系统设计

数据通信 2024年第2期 18-22页

作者：刘志新昆明理工大学信息工程与自动化学院云南昆明650500

基于磁耦合谐振式无线能量传输原理,本文设计了一套无线充电系统。在LC谐振电路的基础上增加高阶谐振补偿结构,克服了传统谐振网络不能隔断直流或将电容串入电路引起的应力变化。此外,采用霍尔传感器与无线通信模块相配合的方式探测无... 详细信息

基于磁耦合谐振式无线能量传输原理,本文设计了一套无线充电系统。在LC谐振电路的基础上增加高阶谐振补偿结构,克服了传统谐振网络不能隔断直流或将电容串入电路引起的应力变化。此外,采用霍尔传感器与无线通信模块相配合的方式探测无线电能接收设备,同时兼具异物检测功能,避免有线充电的诸多不便,解放了繁琐的插拔操作。系统采用模糊PID控制算法对无线电能传输过程加以控制,系统鲁棒性更高,可实现20W大功率的无线电能传输。

关键词：无线充电谐振电路模糊控制无线通信

Flocking with General Local Interaction and Large Population

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Journal of Systems Science & Complexity 2019年第6期32卷 1498-1525页

作者： CHEN Ge liu zhixin Key Laboratory of Systems and Control & National Center for Mathematics and Interdisciplinary Sciences Academy of Mathematics and Systems Science Chinese Academy of Sciences

This paper studies a flocking model in which the interaction between agents is described by a general local nonlinear function depending on the distance between agents. The existing analysis provided sufficient conditions for flocking under an assumption imposed on the system’s closed-loop states; however this assumption is hard to verify. To avoid this kind of assumption the authors introduce some new methods including large deviations theory and estimation of spectral radius of random geometric graphs. For uniformly and independently distributed initial states, the authors establish sufficient conditions and necessary conditions for flocking with large population. The results reveal that under some conditions, the critical interaction radius for flocking is almost the same as the critical radius for connectivity of the initial neighbor graph.

关键词： Consensus Cucker-Smale model flocking model multi-agent systems random geometric graph

Congestion control scheme in ATM networks based on fast tracing-queue

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Journal of Systems Engineering and Electronics 2007年第1期18卷 101-110页

作者： liu zhixin Guan Xinping Inst. of Electrical Engineering Yanshan Univ. Qinhuangdao 066004 E R. China

One of the more challenging and unresolved issues in ATM networks is the congestion control of available bit rate （ABR）. The dynamic controller is designed based on the control theory and the feedback mechanism of explicit rates With the given method of a chosen parameter, it can guarantee the stability of the controller and closed loop system with propagation delay and bandwidth oscillation. It needs less parameters（only one） to be designed. The queue length can converge to the given value in the least steps. The fairness of different connections is considered further. The simulations show better performance and good quality of service（QoS） is achieved.

关键词： ATM networks Congestion control Control theory Tracing-queue QoS