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Stabilization of a class of fuzzy stochastic jump systems with partial information on jump and sojourn parameters

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Science China(Technological Sciences) 2021年第2期64卷 353-363页

作者： CAI Bo WENG Rui zhang ruixian LIANG Ye zhang LiXian School of Astronautics Harbin Institute of TechnologyHarbin 150001China Key Laboratory of System Control and Information Processing Ministry of EducationShanghai 200240China

This paper addresses the problem of the design of controller for fuzzy semi-Markov jump systems with hidden modes against the incomplete information on probability density functions of sojourn time. Two ubiquitous circumstances in practice are taken into account, which are often ignored in other related work:(1) the phenomenon that system modes cannot be accessed entirely is considered proactively;(2) finitely accessible information on probability density functions is studied in this paper. By virtue of hidden semi-Markov chain, the underlying systems are modeled as hidden semi-Markov jump systems, which are more general than semi-Markov jump systems. Sufficient conditions on the existence of desired accessible-mode-dependent fuzzy controller are derived such that the fuzzy hidden semi-Markov jump systems is mean square stable. Based on the emission probability matrix, the presented control policy overcomes the possible mode-mismatch between the system mode and the accessible ***, an example is provided to demonstrate the effectiveness of the proposed control method.

关键词： hidden modes probability density function stochastic switching systems time-varying controller Takagi-Sugeno(T-S)fuzzy system

Li Shizhen and the Spirit of Investigation of Things and the Extension of Knowledge

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Chinese Medicine and Culture 2018年第3期1卷 116-120页

作者： ruixian zhang Research Office of Chinese Materia Medica Literature Institute of Chinese Materia MedicaChina Academy of Chinese Medical SciencesBeijingChina

Li Shizhen was a Ming Dynasty physician and was greatly influenced by the New-Confucian beliefs of the *** Ben Cao Gang Mu(《本草纲目》Compendium of Materia Medica)is a monograph on medicine,its purpose is“to investi... 详细信息

关键词： Ben Cao Gang Mu(《本草纲目》Compendium of Materia Medica) Li Shizhen neo-Confucianism

Robust reinforcement learning with UUB guarantee for safe motion control of autonomous robots

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Science China(Technological Sciences) 2024年第1期67卷 172-182页

作者： zhang ruixian HAN YiNing SU Man LIN ZeFeng LI HaoWei zhang LiXian School of Astronautics Harbin Institute of TechnologyHarbin 150001China School of Management Harbin Institute of TechnologyHarbin 150001China Beijing Institute of Tracking and Telecommunication Technology Beijing 100094China

This paper addresses the issue of safety in reinforcement learning(RL)with disturbances and its application in the safety-constrained motion control of autonomous *** tackle this problem,a robust Lyapunov value function(rLVF)is *** rLVF is obtained by introducing a data-based LVF under the worst-case disturbance of the observed *** the rLVF,a uniformly ultimate boundedness criterion is *** criterion is desired to ensure that the cost function,which serves as a safety criterion,ultimately converges to a range via the policy to be ***,to mitigate the drastic variation of the rLVF caused by differences in states,a smoothing regularization of the rLVF is *** train policies with safety guarantees under the worst disturbances of the observed states,an off-policy robust RL algorithm is *** proposed algorithm is applied to motion control tasks of an autonomous vehicle and a cartpole,which involve external disturbances and variations of the model parameters,*** experimental results demonstrate the effectiveness of the theoretical findings and the advantages of the proposed algorithm in terms of robustness and safety.

关键词： motion control reinforcement learning robustness stability

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Navigation for autonomous vehicles via fast-stable and smooth reinforcement learning

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Science China(Technological Sciences) 2024年第2期67卷 423-434页

作者： zhang ruixian YANG JiaNan LIANG Ye LU ShengAo DONG YiFei YANG BaoQing zhang LiXian School of Astronautics Harbin Institute of TechnologyHarbin 150001China

This paper investigates the navigation problem of autonomous vehicles based on reinforcement learning(RL)with both stability and smoothness *** introducing a data-based Lyapunov function,the stability criterion in mean cost is obtained,where the Lyapunov function has a property of fast ***,an off-policy RL algorithm is proposed to train safe policies,in which a more strict constraint is exerted in the framework of model-free RL to ensure the fast convergence of policy generation,in contrast with the existing RL merely with stability *** addition,by simultaneously introducing constraints on action increments and action distribution variations,the difference between the adjacent actions is effectively alleviated to ensure the smoothness of the obtained policy,instead of only seeking the similarity of the distributions of adjacent actions as commonly done in the past literature.A navigation task of a ground differentially driven mobile vehicle in simulations is adopted to demonstrate the superiority of the proposed algorithm on the fast stability and smoothness.

关键词： autonomous vehicles navigation reinforcement learning smoothness stability

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Near-ground trajectory planning for UAVs via multi-resolution hybrid voxel-surfel map

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Science China(Technological Sciences) 2023年第5期66卷 1245-1254页

作者： GAO TianYu WENG Rui WU Tong zhang ruixian HAN ChengZhe JI XiaoYu LIU Ming School of Astronautics Harbin Institute of TechnologyHarbin 150000China Faculty of Computing Harbin Institute of TechnologyHarbin 150000China

This paper is concerned with trajectory planning problems for UAVs operating near *** existing studies focus on solving the problem of collision-free trajectory planning between pre-defined path points,but ignore the need of navigation method for UAVs working on specific operating surfaces in near-ground *** this paper,a novel near-ground trajectory planning framework is proposed,where the hybrid voxel-surfel map is developed to model the environment with special attention to the uneven operating *** improve the frequency of updates,a probability-based surfel fusion method and a resolution adaptive adjustment method based on the fusion result are proposed in this *** using possibility information in the map,a path search method is established to generate the initial *** trajectory is then further optimized based on map gradient information to generate a final trajectory that tracks the specified operating surface according to the task *** with existing methods,the multi-resolution hybrid voxel-surfel map proposed in this paper has advantages in terms of operating efficiency.A series of experiments in simulated and real scenarios validate the effectiveness of the proposed trajectory planning framework.

关键词： near-ground trajectory planning hybrid voxel-surfel map probability-based surfel fusion operating surface tracking

NA-OR:A path optimization method for manipulators via node attraction and obstacle repulsion

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Science China(Technological Sciences) 2023年第5期66卷 1205-1213页

作者： XIAO GuangZhou WU Tong WENG Rui zhang ruixian HAN YueJiang DONG YiFei LIANG Ye School of Astronautics Harbin Institute of TechnologyHarbin 150001China Faculty of Computing Harbin Institute of TechnologyHarbin 150001China

This paper is concerned with the issue of path optimization for manipulators in multi-obstacle *** at overcoming the deficiencies of the sampling-based path planning algorithm with high path curvature and low safety margin,a path optimization method,named NA-OR,is proposed for manipulators,where the NA(node attraction)and OR(obstacle repulsion)functions are developed to refine the path by *** the iterations of path optimization,the node attraction function is designed to pull the path nodes toward the center of their neighbor nodes,thereby reducing the path curvature and improving the ***,the obstacle repulsion function is developed to push the path nodes out of the potentially unsafe region by generating a repulsive torque on the path nodes,thus improving the safety margin of the *** introducing the effect of NAOR,the optimized path has a significant improvement in path curvature and safety margin compared with the initial path planned by Bi-RRT,which meaningfully enhances the operation ability of manipulators for the applications that give a strong emphasis on *** results on a 6-DOF manipulator in 4 scenarios demonstrate the effectiveness and superiority of the proposed method in terms of the path cost,safety margin,and path smoothness.

关键词： manipulator path planning path optimization obstacle avoidance path curvature safety margin

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《雷公炮炙论》药物炮制辅料考

中国中药杂志 2010年第18期35卷 2493-2496页

作者：张卫张瑞贤中国中医科学院中药研究所北京100700

《雷公炮炙论》中共载268种药物,其中178种药物的炮制中使用辅料。这些辅料有通用炮制辅料也有特殊配伍炮制辅料。《雷公炮炙论》中辅料的使用可以用药物七情配伍来解释。本研究从药物配伍的角度对该书中辅料的选用及辅料炮制的内容作... 详细信息

《雷公炮炙论》中共载268种药物,其中178种药物的炮制中使用辅料。这些辅料有通用炮制辅料也有特殊配伍炮制辅料。《雷公炮炙论》中辅料的使用可以用药物七情配伍来解释。本研究从药物配伍的角度对该书中辅料的选用及辅料炮制的内容作以阐释,提出要注意古今药物主治功效的变化及历史大环境的影响。

关键词：雷公炮炙论辅料证类本草

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先秦时期非医学文献对“味”的认识

中国中药杂志 2010年第4期35卷 511-514页

作者：张瑞贤张卫中国中医科学院中药研究所北京100700

本研究对先秦时期的非医学文献如十三经、诸子百家等进行全面系统的梳理,在此基础上对味的含义运用发生认识学的方法进行了分析,指出先秦时期味的两个涵义"滋味"的产生应早于"五行属性"之味的产生,并简述了对于当时人们对于味及五味在... 详细信息

本研究对先秦时期的非医学文献如十三经、诸子百家等进行全面系统的梳理,在此基础上对味的含义运用发生认识学的方法进行了分析,指出先秦时期味的两个涵义"滋味"的产生应早于"五行属性"之味的产生,并简述了对于当时人们对于味及五味在保健医疗中的认识。

关键词：中医五味先秦文献

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用户需求导向的图书馆在线学习支持服务研究

图书馆工作与研究 2020年第1期 58-64页

作者：张瑞贤河北对外经贸职业学院图书馆

用户需求是图书馆提供学习支持服务的基础。由于用户需求的复杂性、动态性、零散性、多样性和即时性等原因,图书馆很难及时捕捉、了解和回应用户需求,导致图书馆在线学习支持服务难以令用户满意。本文基于需求管理理论,在结合图书馆实... 详细信息

用户需求是图书馆提供学习支持服务的基础。由于用户需求的复杂性、动态性、零散性、多样性和即时性等原因,图书馆很难及时捕捉、了解和回应用户需求,导致图书馆在线学习支持服务难以令用户满意。本文基于需求管理理论,在结合图书馆实践的基础上,构建了用户学习需求管理概念框架和用户在线学习需求管理体系,分析了该体系对原有图书馆学习支持服务的改进之处,并提出了基于该体系优化图书馆在线学习支持服务的策略。

关键词：图书馆在线学习支持服务需求管理学习需求用户需求