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Non-fragile switched H_∞ control for morphing aircraft with asynchronous switching

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Chinese Journal of Aeronautics 2017年第3期30卷 1127-1139页

作者： haoyu cheng Chaoyang DONG Weilai JIANG Qing WANG Yanze HOU School of Aeronautic Science and Engineering Beihang University Beijing 100083 China College of Electrical and Information Engineering Hunan University Changsha 410082 China School of Automation Science and Electrical Engineering Beihang University Beijing 100083 China Institute of Manned Space System Engineering Beijing 100094 China

This paper deals with the problem of non-fragile linear parameter-varying（LPV） H_∞ control for morphing aircraft with asynchronous *** switched LPV model of morphing aircraft is established by Jacobian linearization approach according to the nonlinear *** data missing is taken into account in the link from sensors to controllers and the link from controllers to actuators,which satisfies Bernoulli *** non-fragile switched LPV controllers are constructed with consideration of the uncertainties of controllers and asynchronous switching *** parameter-dependent Lyapunov functional method and mode-dependent average dwell time（MDADT） method are combined to guarantee the stability and prescribed performance of the *** sufficient conditions on the solvability of the problem are derived in the form of linear matrix inequalities（LMI）.In order to achieve higher efficiency of the designing process,an algorithm is applied to divide the whole set into subsets *** results are provided to verify the effectiveness and superiority of the method in the paper.

关键词： Asynchronous switching Data missing Morphing aircraft Non-fragile H_∞ control Switched linear parameter varying system

NK cells in immunotolerant organs

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Cellular & Molecular Immunology 2013年第3期10卷 202-212页

作者： haoyu Sun cheng Sun Zhigang Tian Weihua Xiao Institute of Immunology School of Life Sciences University of Science and Technology of China Hefei China

Organs such as the liver, uterus and lung possess hallmark immunotolerant features, making these organs important for sustaining self-homeostasis. These organs contain a relatively large amount of negative regulatory immune cells, which are believed to take part in the regulation of immune responses. Because natural killer cells constitute a large proportion of all lymphocytes in these organs, increasing attention has been given to the roles that these cells play in maintaining immunotolerance. Here, we review the distribution, differentiation, phenotypic features and functional features of natural killer cells in these immunotolerant organs, in addition to the influence of local microenvironments on these cells and how these factors contribute to organ-specific diseases.

关键词： immunotolerance liver lung natural killer cell uterus

Cooperative guidance law based on super-twisting observer for target maneuvering

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Journal of Systems Engineering and Electronics 2024年第5期35卷 1304-1314页

作者： GAO Mengjing YAN Tian HAN Bingjie cheng haoyu FU Wenxing HAN Bo Unmanned System Research Institute Northwestern Polytechnical UniversityXi’an 710072China AVIC Xi’an Aeronautics Computing Technique Research Institute Xi’an 710072China 93525 Troops Shigatse 857000China

To solve the problem that multiple missiles should simultaneously attack unmeasurable maneuvering targets,a guidance law with temporal consistency constraint based on the super-twisting observer is ***,the relative motion equations between multiple missiles and targets are established,and the topological model among multiple agents is ***,based on the temporal consistency constraint,a cooperative guidance law for simultaneous arrival with finite-time convergence is ***,the unknown target maneuver-ing is regarded as bounded *** on the second-order sliding mode theory,a super-twisting sliding mode observer is devised to observe and track the bounded interfer-ence,and the stability of the observer is *** with the existing research,this approach only needs to obtain the sliding mode variable which simplifies the design *** simulation results show that the designed cooperative guidance law for maneuvering targets achieves the expected *** ensures successful cooperative attacks,even when confronted with strong maneuvering targets.

关键词： cooperative guidance super-twisting target maneuver finite time convergence.

Intelligent Control for Unmanned Flight Vehicles via Deep Reinforcement Learning

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Intelligent Control for Unmanned Flight Vehicles via Deep Re...

第32届中国控制与决策会议

作者： haoyu cheng Xiaofeng Zhang Hanqiao Huang Xiaohan Zhao the School of Astronautics Northwestern Polytechnical University

The problem of intelligent control for unmanned flight vehicles is studied in this *** linear model of unmanned flight vehicle is obtained by Jacobian linearization method according to the nonlinear *** process of controller design can be divided into two ***,to ensure the stability and prescribed performance of the closed loop system,the robust controller is given in terms of linear matrices inequalities based on robust control ***,the intelligent controller is proposed to improve the transient performance via deep reinforcement *** parameters of controller can be tuned automatically in a neighborhood of robust controller’s *** the end,the simulation results are given to illustrated the effectiveness and superiority of the proposed method.

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高应力硐室围岩三轴蠕变及声发射特征研究

岩石力学与工程学报 2023年第S1期42卷 3367-3376页

作者：贺安王璐成昊宇杨姝瑜西华大学建筑与土木工程学院四川成都610039 四川大学水利水电学院四川成都610065

针对高应力岩体工程开挖后硐壁附近围岩长期变形问题,利用MTS815 Flex Text GT岩石力学试验系统和PCI-Ⅱ声发射三维监测系统,针对高应力硐室围岩,开展大理岩试件三轴蠕变试验及声发射实时监测,探讨硐室开挖后围岩在较小侧向压力下的蠕... 详细信息

针对高应力岩体工程开挖后硐壁附近围岩长期变形问题,利用MTS815 Flex Text GT岩石力学试验系统和PCI-Ⅱ声发射三维监测系统,针对高应力硐室围岩,开展大理岩试件三轴蠕变试验及声发射实时监测,探讨硐室开挖后围岩在较小侧向压力下的蠕变力学特性和声发射特征。结果表明:大理岩的多级蠕变全过程应力-应变曲线具有5个阶段,岩样具有脆性破坏特征,横向变形较轴向变形具有更显著的蠕变特征;声发射特征表现出明显的应力响应和时效特征,且与典型蠕变3个阶段相匹配,在减速和稳态蠕变阶段,声发射振铃计数率和能量率呈线性增长趋势,加速阶段声发射振铃计数率和能量率呈现指数型增长,且声发射变化对应的时间点提前于应变加速点,可作为大理岩蠕变破坏的前兆特征;基于AF和RA值表征的大理岩内部微裂纹发展特征,大理岩蠕变破坏是张拉破坏和剪切破坏共同作用的结果。

关键词：岩石力学大理岩三轴蠕变横向蠕变声发射破坏模式

H∞ Consensus for Discrete-time Multi-agent Systems Subject to Distributed Delay and Switching Topologies

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H∞ Consensus for Discrete-time Multi-agent Systems Subject ...

H∞ Consesus Control of Asynchronously Switched Multi-Agent Systems With Average Dwell Time

第40届中国控制会议

作者： Bojun Zhang Hanqiao Huang Xinpeng Xu haoyu cheng Yali Wei School of Marine Science and Technology Northwestern Polytechnical University Unmanned System Research Institute Northwestern Polytechnical University Shanghai Aerospace Control Technology Institute School of Astronautics Northwestern Polytechnical University

This paper is concerned with the issue of weighted fconsensus for discrete-time multi-agent systems with time-varying delay and switching topologies. The objective is designing a dynamic output feedback protocol in the presence of external perturbations such that the system achieves consensus in mean square and has a prescribed performance level. Firstly, the consensus design is converted to a standard control problem by reconstructing the closed-loop system as a reduced-order system. Then, by means of the multiple Lyapunov-Krasovskii functional method, the delay-dependent bounded real lemma is derived to guarantee the stability of closed-loop system. Based on these, sufficient conditions for the existence of the required dynamic output feedback protocol is developed in the form of a series of solvable linear matrix inequalities. Finally, numerical example and simulation results are given to illustrate the effectiveness of the obtained results.

关键词： Multi-agent system Consensus Average dwell-time Time-varying delay Dynamic output feedback protocol

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H∞ Consesus Control of Asynchronously Switched Multi-Agent ...

第40届中国控制会议

作者： Linpeng Xu Bolan Wang Hanqiao Huang haoyu cheng Ruijia Song School of Marine Science and Technology Northwestern Polytechnical University Unmanned System Research Institute Northwestern Polytechnical University Shanghai Aerospace Control Technology Institute School of Astronautics Northwestern Polytechnical University

The problem of H∞ consesus control for asynchronously switched continuous-time multi-agent systems is investigated in this paper. There always exists asynchronous switching due to time delay and packet losses of network transmission which means that the switching of controllers will lag behind the switching of system modes, which will lead to performance degradation. First, the model of switched multi-agent systems is established. The H∞ consensus issue can be converted as a H∞ control problem via system reduction. Considering asynchronous switching phenomenon, the mean-square asymptotic stability is analyzed by the aid of multiple Lyapunov functional method and average dwell time（ADT） method. The sufficient conditions to ensure the closed-loop stable with prescribed performance are given in the form of linear matrix inequalities（LMIs）. In the end,an example is given to verify the feasibility of the proposed approach.

关键词： Asynchronous switching average dwell time multi-agent systems consensus

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复合控制导弹反步滑模IGC自适应设计方法

系统工程与电子技术 2018年第10期40卷 2325-2333页

作者：夏川董朝阳王青程昊宇北京航空航天大学航空科学与工程学院北京100191 北京航空航天大学自动化科学与电气工程学院北京100191 西北工业大学航天学院陕西西安710072

针对直接力/气动力复合控制导弹,基于扩张状态观测器和反步终端滑模控制,提出一种制导与控制一体化设计方法。通过对系统不确定性进行观测,并设计自适应律补偿观测误差,实现系统对复合干扰的抑制。随后引入虚拟控制力矩的概念,规避了直... 详细信息

针对直接力/气动力复合控制导弹,基于扩张状态观测器和反步终端滑模控制,提出一种制导与控制一体化设计方法。通过对系统不确定性进行观测,并设计自适应律补偿观测误差,实现系统对复合干扰的抑制。随后引入虚拟控制力矩的概念,规避了直接在控制器中求解控制量,基于梯度下降法和混合整数线性规划提出一种自适应控制分配策略,充分利用系统已有信息,解决控制量分配实时性要求和精度要求的矛盾。最后通过数值仿真证明,所提出的综合设计方法能够在系统存在内外扰动时,保证系统收敛且使得控制量减小,制导精度提高。

关键词：制导控制一体化扩张状态观测器反步终端滑模自适应补偿虚拟控制力矩自适应控制分配

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采用利希滕贝格图的高超声速飞行器轨迹优化

宇航学报 2024年第2期45卷 181-191页

作者：张笑妍程昊宇韩博闫杰西北工业大学无人系统技术研究院西安710072 中国人民解放军93525部队日喀则857000

针对复杂约束条件下高超声速飞行器再入轨迹优化问题,提出一种混合算法进行求解,以解决现有轨迹优化方法对初值的强依赖性以及易陷入局部最优等问题。将高超声速飞行器再入轨迹优化建模成一个非线性规划问题,并设计双层优化结构进行求... 详细信息

针对复杂约束条件下高超声速飞行器再入轨迹优化问题,提出一种混合算法进行求解,以解决现有轨迹优化方法对初值的强依赖性以及易陷入局部最优等问题。将高超声速飞行器再入轨迹优化建模成一个非线性规划问题,并设计双层优化结构进行求解。上层中,提出一种基于利希滕贝格图的自适应分段利希滕贝格算法(Adaptive piecewise Lichtenberg algorithm,APLA),为高斯伪谱法提供良好的初值。APLA通过引入拉丁超立方体抽样提升算法初始触发点的效能,引入全局至局部搜索分段策略及自适应因子提高算法收敛速度和收敛精度,改善算法易陷入局部最优等情况。下层中,高斯伪谱法在最优解附近具有较好的收敛速度和较高收敛精度,因此使用高斯伪谱法以加快搜索过程,提升解的全局最优性。综上,提出再入轨迹优化混合算法(APLA_GPM),实现对高超声速飞行器再入轨迹优化问题快速、准确求解。仿真结果表明,APLA_GPM在高超声速飞行器再入轨迹优化方面具有更快的收敛速度、更高的精度以及更强的鲁棒性。

关键词：高超声速飞行器再入轨迹优化利希滕贝格算法高斯伪谱法