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Fuzzy Static Output Feedback H_∞ Control for Nonlinear Systems Subject to Parameter Uncertainties

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Journal of Systems Science & Complexity 2018年第2期31卷 343-371页

作者： zhao tao DIAN Songyi School of Electrical Engineering and Information Sichuan University

This study is concerned with the stabilization issue of nonlinear systems subject to parameter uncertainties. An interval type-2 T-S fuzzy model is used to represent the nonlinear systems subject to parameter uncertainties. An interval type-2 fuzzy static output feedback controller is designed to synthesize the interval type-2 T-S fuzzy systems. The membership-function-dependent stability conditions are derived by utilizing the information of upper and lower membership functions. The proposed stability conditions are presented in the form of linear matrix inequalities（LMIs）. LMI-based stability conditions for interval type-2 fuzzy static output feedback H_∞ control synthesis are also *** simulation examples are given to show the superiority of the proposed approach.

关键词： Interval type-2 fuzzy controller parameter uncertainties static output feedback control T-S fuzzy systems.

Sleep disturbances and psychomotor retardation in the prediction of cognitive impairments in patients with major depressive disorder

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World Journal of Psychiatry 2024年第10期14卷 1474-1483页

作者： Mi Wang Wen-tao Chen Hao-Ting Wang Bang-Shan Liu Yu-Meng Ju Qiang-Li Dong Xiao-Wen Lu Jin-Rong Sun Liang Zhang Hua Guo Fu-tao zhao Wei-Hui Li Li Zhang Ze-Xuan Li Mei Liao Yan Zhang Jin Liu Ling-Jiang Li Department of Mental Health Center Xiangya HospitalCentral South UniversityChangsha 410008Hunan ProvinceChina National Clinical Research Center of Geriatric Disorders Xiangya HospitalCentral South UniversityChangsha 410008Hunan ProvinceChina Department of Psychiatry National Clinical Research Center for Mental DisordersThe Second Xiangya Hospital of Central South UniversityChangsha 410011Hunan ProvinceChina Department of Psychiatry Zhumadian Psychiatric HospitalZhumadian 463000Henan ProvinceChina

BACKGROUND Symptoms of depression and comorbid anxiety are known risk factors for cognitive impairment in major depressive disorder(MDD).Understanding their relationships is crucial for developing targeted interventions to mitigate cognitive impairments in MDD *** expect that the severity of sleep disturbances and other depressive symptoms will be positively correlated with the degree of cognitive *** also hypothesize that anxiety symptoms,especially psychic anxiety,is a key factor in predicting cognitive performance in MDD patients and may indirectly contribute to cognitive impairment by affecting sleep disturbances and other potential *** To determine which dimension of the depressive and anxiety symptoms predicts cognitive impairment during a depressive *** A comprehensive neurocognitive test battery assessed executive function,attention,processing speed,and memory in 162 medication-free MDD patients and 142 matched healthy *** 24-item Hamilton Depression Rating Scale was used to assess depressive symptoms,and the 14-item Hamilton Anxiety Scale was used to assess anxiety *** regression analyses and mediation analyses were conducted to evaluate the impact of depressive and anxiety symptoms,as well as their interactions,on cognitive *** Among the depressive symptoms,sleep disturbances were associated with poorer executive function(P=0.004),lower processing speed(P=0.047),and memory impairments(P<0.001),and psychomotor retardation(PR)was associated with lower processing speed in patients with MDD(P=0.019).Notably,PR was found to mediate the impact of sleep disturbances on the processing *** anxiety symptoms,psychic anxiety,rather than somatic anxiety,was associated with cognitive impairments in all *** disturbances mediated the effect of psychic anxiety on executive function[β=-0.013,BC CI(-0.027,-0.001)]and memory[β=-0.149,BC CI(-0.237,-0.063)],while PR mediated its ef

关键词： Major depressive disorder Cognitive impairment Depressive symptoms Anxiety symptoms Sleep disturbance Psychomotor retardation

A New Class for Large Sets of Almost Hamilton Cycle Decompositions

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Acta Mathematicae Applicatae Sinica 2017年第4期33卷 865-870页

作者： Hong-tao zhao School of Mathematics and Physics North China Electric Power University Beijing 102206 China

A k-cycle system of order v with index A, denoted by CS（v, k, λ）, is a collection A of k-cycles （blocks） of Kv such that each edge in Kv appears in exactly λ blocks of A. A large set of CS（v, k, λ）s is a partition of the set of all k-cycles of Kv into CS（v, k, λ）s, and is denoted by LCS（v, k, λ）. A （v - 1）-cycle in K, is called almost Hamilton. The completion of the existence problem for LCS（v, v- 1,λ） depends only on one case： all v ≥ 4 for λ=2. In this paper, it is shown that there exists an LCS（v,v - 1,2） for all v ≡ 2 （mod 4）, v ≥ 6.

关键词： large set cycle system almost Hamilton cycle decomposition symmetric group complete auto-morphism group

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基于无人值守的智能化能源管理系统

兵工自动化 2024年第8期43卷 47-50页

作者：赵涛王屹华吕孟恩侯刚西北机电工程研究所压制武器总体部陕西咸阳712099

针对我国火炮智能科技与无人值守等相关技术的研究现状,提出火炮无人值守能源管理与建设方案。采用变能装置储能,实现能源合理利用与分配。利用神经网络、智能学习等技术,实现基于任务导向模型规则的知识型系统。通过故障的隔离、诊断... 详细信息

针对我国火炮智能科技与无人值守等相关技术的研究现状,提出火炮无人值守能源管理与建设方案。采用变能装置储能,实现能源合理利用与分配。利用神经网络、智能学习等技术,实现基于任务导向模型规则的知识型系统。通过故障的隔离、诊断和重构,实现能源系统的自主故障管理。结果表明:该研究能够满足地面武器能源的智能化、无人化、信息化管理要求,对未来火炮无人值守能源分系统的研究与工程化应用具有较为重要的意义。

关键词：无人值守未来战争能源管理火力打击系统智能化

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齿轮摆杆式光纤流量传感器的设计与实验

机械设计与制造 2024年第6期400卷 111-115页

作者：胡浩钟丽琼赵涛马龙贵阳学院机械工程学院贵州贵阳550003

对一种齿轮摆杆式强度调制光纤流量传感器进行了设计与实验。首先,提出了一种强度调制型光纤流量传感器系统,阐述了传感器系统的工作原理,再详细论述了传感器的探头结构及工作原理;然后,依据流体力学与光纤强度调制原理建立了传感器的... 详细信息

对一种齿轮摆杆式强度调制光纤流量传感器进行了设计与实验。首先,提出了一种强度调制型光纤流量传感器系统,阐述了传感器系统的工作原理,再详细论述了传感器的探头结构及工作原理;然后,依据流体力学与光纤强度调制原理建立了传感器的数学模型M,在理论模型的基础上,进行了仿真实例分析,得出了传感器摆动杆重量m,受力板半径r,通流管道半径R,被测流体密度等参数变化时的Q-M曲线;最后,进行了传感器检测实验,得出了I-曲线,及其拟合方程。实验结果表明:随着传感器摆动杆重量的减小,或者受力板半径的增大,传感器的灵敏度会增大;随着被测流体密度取值的减小,或者通流管道半径取值的增大,传感器的灵敏度会减小;传感器接收光信号强度与入射光纤束有效发射面积弧度具有近似线性关系。研究表明,这里设计的齿轮摆杆式强度调制光纤流量传感器能实现流体流速的检测,且具有较好的灵敏度及线性度。

关键词：齿轮摆杆式光纤流量传感器设计与实验

Algebraic Method‑Based Point‑to‑Point Trajectory Planning of an Under‑Constrained Cable‑Suspended Parallel Robot with Variable Angle and Height Cable Mast

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Chinese Journal of Mechanical Engineering 2020年第4期33卷 45-62页

作者： tao zhao Bin Zi Sen Qian Jiahao zhao School of Mechanical Engineering Hefei University of TechnologyHefei 230009China Chemical Science and Engineering College North Minzu UniversityYinchuan 750021China

To avoid impacts and vibrations during the processes of acceleration and deceleration while possessing flexible working ways for cable-suspended parallel robots(CSPRs),point-to-point trajectory planning demands an under-constrained cable-suspended parallel robot(UCPR)with variable angle and height cable mast as described in this *** end-effector of the UCPR with three cables can achieve three translational degrees of freedom(DOFs).The inverse kinematic and dynamic modeling of the UCPR considering the angle and height of cable mast are *** motion trajectory of the end-effector comprising six segments is *** connection points of the trajectory segments(except for point P3 in the X direction)are devised to have zero instantaneous velocities,which ensure that the acceleration has continuity and the planned acceleration curve achieves smooth *** trajectory is respectively planned using three algebraic methods,including fifth degree polynomial,cycloid trajectory,and double-S velocity *** results indicate that the trajectory planned by fifth degree polynomial method is much closer to the given trajectory of the *** simulation and experiments are accomplished for the given trajectory based on fifth degree polynomial *** the points where the velocity suddenly changes,the length and tension variation curves of the planned and unplanned three cables are compared and *** OptiTrack motion capture system is adopted to track the end-effector of the UCPR during the *** effectiveness and feasibility of fifth degree polynomial planning are validated.

关键词： Under-constrained cable-suspended parallel robot Variable angle and height cable mast Inverse kinematic and dynamic modeling Algebraic method Point-to-point trajectory planning

基于实例的附着式升降脚手架中桁架结构优化布置的有限元分析

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工程建设 2024年第6期56卷 21-26页

作者：张晓通赵涛甘肃第七建设集团股份有限公司甘肃兰州730000

附着式升降脚手架已经成为了建筑脚手架的主流,桁架作为附着式升降脚手架的主要受力构件,对架体稳定性具有决定性的影响,因此研究桁架设置的位置、数量对架体结构体稳定性能的影响很重要。文章以三跨四机位的附着式升降脚手架结构为研... 详细信息

附着式升降脚手架已经成为了建筑脚手架的主流,桁架作为附着式升降脚手架的主要受力构件,对架体稳定性具有决定性的影响,因此研究桁架设置的位置、数量对架体结构体稳定性能的影响很重要。文章以三跨四机位的附着式升降脚手架结构为研究对象,利用ANSYS有限元软件,通过对不同桁架设置组合形式下形成的静态应力和静态应变云图分析对比,统计分析架体整体受力应力及挠度变化情况,判断架体的结构整体稳定性能。研究结果表明:基于实例的架体底层大桁架必须设置,再增设底层内部小桁架和上部一道桁架后,架体整体的应力和位移达到了最优值,可为今后同类架体合理设置桁架数量、位置提供一定参考。

关键词：附着式升降脚手架桁架三跨四机位组合形式有限元

Active event-driven reliable defense control for interconnected nonlinear systems under actuator faults and denial-of-service attacks

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Science China(Information Sciences) 2022年第6期65卷 155-171页

作者： Bin GUO Songyi DIAN tao zhao College of Electrical Engineering Sichuan University

This study investigates the reliable control design for a class of interconnected nonlinear systems subjected to actuator faults, disturbances, and denial-of-service(DoS) attacks. DoS attacks are carried out in both sensor and controller channels. An integrated event-observer-based security sliding mode fault-tolerant control approach is presented to defend against DoS attacks and compensate for faults and *** be more specific, the fuzzy logic system(FLS) theory is used to approximate the unknown nonlinear component first. Using the output measurement and sensor channel triggered output information, an FLS aided nonlinear estimator is put forward, in which the faults and disturbances are reconstructed. Then, to achieve the trajectory tracking purpose in the presence of DoS attacks, actuator faults, and disturbances, an adaptive sliding mode manifold is established, based on which an event-driven mechanism is established and a reliable controller is designed. In the controller scheme, the fault compensation and disturbance rejection mechanisms are also included synchronously. The tracking ability is analyzed using the Lyapunov method and the FLS theory, followed by applications to an interconnected power network system and an interconnected inverted pendulum system to demonstrate the applicability of the proposed method.

关键词： interconnected nonlinear system actuator fault DoS attack disturbance fault-tolerant control event-driven control

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渭北长武苹果黑星病发生重的原因及对策

北方果树 2024年第1期 52-53页

作者：谢超杰赵涛陕西省长武县果业服务中心陕西长武713600

近年来,苹果黑星病在渭北地区长武县普遍发生严重,作者对发病规律和发病原因进行了认真分析,并提出有效的防治措施,确保苹果产业实现高质量发展。

关键词：黑星病发生原因对策