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Science China(Information Sciences) 2025年第1期 306-321页

作者： Cuijuan ZHANG Lianghao JI Shasha YANG Xing GUO Huaqing LI Chongqing Key Laboratory of Image cognition Chongqing University of Posts and Telecommunications Key Laboratory of Intelligent Perception and Computing of Anhui Province Anqing Normal University College of Electronic and Information engineering Southwest University

This study uses event-triggered(ET) and reinforcement learning methods to investigate the optimal consensus control problem for cooperative-competitive multiagent systems. It proposes a novel distributed ET control strategy, which relies on a prioritized experience replay(PER) policy. This strategy not only conserves communication resources but also ensures acceptable system performance. To implement the proposed method, actor-critic(AC) dual-structured neural networks(NNs) are used to approximate the value function and control policy. In the AC NNs, the weight estimates for the NNs are updated at the moment of event triggering, resulting in a nonperiodic weight adjustment pattern. This approach decreases the computational cost in comparison with the traditional ET mechanism. The PER-based ET mechanism makes full use of valid historical data and effectively establishes a balance between system performance and communication resource ***, it does not require the following two conditions in most existing studies:(1) requirement of the system dynamics model to be known, and(2) persistent excitation. In addition, Zeno behavior is excluded from this study. Finally, a simulation is conducted to confirm the validity of the suggested approach.

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engineering cognition of State Transition Matrix and the Unique Discrimination Method

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Wuhan University Journal of Natural Sciences 2020年第1期25卷 65-70页

作者： ZHANG Yuye College of Physics and Electronics engineering Xianyang Normal CollegeXianyang 712000ShaanxiChina

State transition matrix is an important concept in modern control system. It studies the motion law of linear control system from initial state to any state at time t. In this paper, joining an engineering example, an approach to determine zero-input responses is developed, and the design of simulation experiments with the aid of Matlab is used to illustrate the physical meaning of it. Furthermore, during the engineering application, for the discrimination of state transition matrix, a discrimination method of state transition matrix is proposed based on related theorems and an effective method is derived by calculating characteristics during tedious verification of theorem. The simulation results have proved the correctness of system analysis by using such discrimination method under different parameter models.

关键词： state transition matrix simulation experiment homogeneous state equation discrimination

Chronic electrical stimulation induces functional network changes in cortical neuron cultures

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Science China(Technological Sciences) 2020年第4期63卷 637-647页

作者： WU SongFang WANG LuBin ZHAO YuWei SUN HongJi LANG YiRan WANG ChangYong HAN JiuQi WANG Yan HAN Yao Department of Neural engineering and Biological Interdisciplinary Studies Institute of Military Cognition and Brain SciencesAcademy of Military Medical SciencesBeijing 100850China

Recent studies demonstrated that a functional brain network could be regarded as a complex *** the help of network theory,neuroscientists can identify common organizational principles of the functional brain *** a consequence,some non-random organizational features,such as"small world"(most of the nodes are not connected directly but can communicate with few intermediate relay steps)and"rich club"(nodes that are rich in connections tend to form strongly interconnected clubs),have been found in functional brain ***,the"small world"organizational feature of neuronal functional networks in vitro was found to be influenced by external ***,little is known about the influence of chronic electrical stimulation on functional networks of dissociated cortical cultures during network *** the present study,cortical cultures were electrically stimulated at a frequency of 0,0.02,and 0.2 Hz,between 7 and 26 days in vitro(DIV).The spontaneous activity of the cortical cultures was recorded using ***,a cross-covariance method and graph theory were applied to investigate organizational feature of functional *** results showed that over 3 weeks of stimulation,the network density significantly increased with maturation in the control and 0.02 Hz stimulation groups,but not in 0.2 Hz stimulation ***,all the cultures had a small-world topology at 14,18,22,and 26 DIV,free from the effect of chronic electrical ***,we found an asymmetry effect that partial electrical stimulation inhibited the formation of node connections in stimulated *** effect was more pronounced at 0.2 Hz than at 0.02 Hz *** results suggest that electrical stimulation does not affect the small-world properties of neural ***,electrical stimulation modulates connectivity patterns,and neurons within the stimulated area are less connected than neurons outside the stimulated area.

关键词： neural culture graph theory connectivity microelectrode arrays electrical stimulation

Nitrogen-doped microporous graphite-enhanced copper plasmonic effect for solar evaporation

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Carbon Energy 2024年第3期6卷 215-223页

作者： Xintao Wu Chengcheng Li Ziqi Zhang Yang Cao Jieqiong Wang Xinlong Tian Zhongxin Liu Yijun Shen Mingxin Zhang Wei Huang School of Marine Science and engineering School of Chemistry and Chemical EngineeringHainan UniversityHaikouHainanChina Key Laboratory of Child cognition and Behavior Development of Hainan Province Qiongtai Normal UniversityHaikouHainanChina

Water scarcity is a global challenge,and solar evaporation technology offers a promising and eco-friendly solution for freshwater *** conversion materials(PCMs)are crucial for solar *** photothermal conversion efficiency and reducing water evaporation enthalpy are the two key strategies for the designing of *** desired PCMs that combine both of these properties remain a challenging task,even with the latest advancements in the ***,we developed copper nanoparticles(NPs)with different conjugated nitrogen-doped microporous carbon coatings(Cu@C–N)as *** microporous carbon enveloping layer provides a highly efficient pathway for water transport and a nanoconfined environment that protects Cu NPs and facilitates the evaporation of water clusters,reducing the enthalpy of water ***,the conjugated nitrogen nodes form strong metal-organic coordination bonds with the surface of copper NPs,acting as an energy bridge to achieve rapid energy transfer and provide high solar-to-vapor conversion *** Cu@C–N exhibited up to 89.4%solar-to-vapor conversion efficiency and an evaporation rate of 1.94 kgm^(−2) h^(−1) under one sun irradiation,outperforming conventional PCMs,including carbon-based materials and semiconductor *** findings offer an efficient design scheme for high-performance PCMs essential for solar evaporators to address global water scarcity.

关键词： nanoconfinement photothermal conversion materials plasmonic resonance seawater desalination solar evaporation

The Fitzpatrick-Neville-Type Algorithm for Multivariate Vector-Valued Osculatory Rational Interpolation

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Journal of Systems Science & Complexity 2015年第1期28卷 222-242页

作者： XIA Peng ZHANG Shugong LEI Na KIM Zhangyong School of Mathematics Liaoning University Automated Reasoning and cognition Key Laboratory of Chongqing School of Mathematics Key Laboratory of Symbolic Computation and Knowledge Engineering(Ministry of Education)Jilin University

In this paper,the authors first apply the Fitzpatrick algorithm to multivariate vectorvalued osculatory rational *** based on the Fitzpatrick algorithm and the properties of an Hermite interpolation basis,the authors present a Fitzpatrick-Neville-type algorithm for multivariate vector-valued osculatory rational *** may be used to compute the values of multivariate vector-valued osculatory rational interpolants at some points directly without computing the interpolation function explicitly.

关键词： Fitzpatrick algorithm GrSbner basis module vector-valued osculatory rational interpolation.

Event-triggered predefined-time control for full-state constrained nonlinear systems: A novel command filtering error compensation method

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Science China(Technological Sciences) 2024年第9期67卷 2867-2880页

作者： PAN YingNan CHEN YiLin LIANG HongJing College of Control Science and engineering Bohai UniversityJinzhou 121013China School of Automation engineering University of Electronic Science and Technology of ChinaChengdu 611731China Laboratory of Electromagnetic Space cognition and Intelligent Control Beijing 100089China

In this paper, a command filter-based adaptive fuzzy predefined-time event-triggered tracking control problem is investigated for uncertain nonlinear systems with time-varying full-state constraints. By designing a sliding mode differentiator, the inherent computational complexity problem within the predefined-time backstepping framework is solved. Different from the existing command filter-based finite-time and fixed-time control strategies that the convergence time of the filtering error is adjusted through the system initial value or numerous parameters, a novel command filtering error compensation method is presented,which tunes one control parameter to make the filtering error converge in the predefined time, thereby reducing the complexity of design and analysis of processing the filtering error. Then, an improved event-triggered mechanism(ETM) that builds upon the switching threshold strategy, in which an inverse cotangent function is designed to replace the residual term of the ETM,is proposed to gradually release the controller's dependence on the residual term with increasing time. Furthermore, a tan-type nonlinear mapping technique is applied to tackle the time-varying full-state constraints problem. By the predefined-time stability theory, all signals in the uncertain nonlinear systems exhibit predefined-time stability. Finally, the feasibility of the proposed algorithm is substantiated through two simulation results.

关键词： predefined-time control command filtering error compensation method event-triggered mechanism time-varying full-state constraints uncertain nonlinear systems

Multiple Targets Localization Algorithm Based on Covariance Matrix Sparse Representation and Bayesian Learning

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Journal of Beijing Institute of Technology 2024年第2期33卷 119-129页

作者： Jichuan Liu Xiangzhi Meng Shengjie Wang School of Electronic engineering Xidian UniversityXi’an 710071China Hebei Key Laboratory of Electromagnetic Spectrum cognition and Control Shijiazhuang 050081China

The multi-source passive localization problem is a problem of great interest in signal pro-cessing with many *** this paper,a sparse representation model based on covariance matrix is constructed for the long-range localization scenario,and a sparse Bayesian learning algo-rithm based on Laplace prior of signal covariance is developed for the base mismatch problem caused by target deviation from the initial point *** adaptive grid sparse Bayesian learning targets localization(AGSBL)algorithm is *** AGSBL algorithm implements a covari-ance-based sparse signal reconstruction and grid adaptive localization dictionary ***-tion results show that the AGSBL algorithm outperforms the traditional compressed-aware localiza-tion algorithm for different signal-to-noise ratios and different number of targets in long-range scenes.

关键词： grid adaptive model Bayesian learning multi-source localization

Pyramid-resolution person restoration for cross-resolution person re-identification

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Science China(Information Sciences) 2024年第6期67卷 451-452页

作者： Chunlei PENG Bo WANG Decheng LIU Nannan WANG Xinbo GAO State Key Laboratory of Integrated Services Networks Xidian University School of Cyber engineering Xidian University School of Telecommunications engineering Xidian University Chongqing Key Laboratory of Image cognition Chongqing University of Posts and Telecommunications

Person images captured by surveillance cameras are typically with various resolutions and are susceptible to pose changes,occlusion and background variations,thus affecting the performance of person Re *** approaches[1,2]either use an image restoration model to restore the lowresolution images to obtain a corresponding high-resolution image,

关键词： Restoration

Hawk and pigeon's intelligence for UAV swarm dynamic combat game via competitive learning pigeon-inspired optimization

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Science China(Technological Sciences) 2022年第5期65卷 1072-1086页

作者： YU YuePing LIU JiChuan WEI Chen School of Automation Science and Electrical engineering Beihang UniversityBeijing100083China School of Electronic engineering Xidian UniversityXi’an710071China Hebei Key Laboratory of Electromagnetic Spectrum cognition and Control The 54th Research Institute of CETCShijiazhuang050081China

For unmanned aerial vehicle(UAV)swarm dynamic combat,swarm antagonistic motion control and attack target allocation are extremely challenging *** this paper,the competitive learning pigeon-inspired optimization(CLPIO)algorithm is proposed to handle the cooperative dynamic combat problem,which integrates the distributed swarm antagonistic motion and centralized attack target ***,the threshold trigger strategy is presented to switch two *** seek a feasible and optimal combat scheme,a dynamic game approach combined with hawk grouping mechanism and situation assessment between sub-groups is designed to guide the solution of the optimal attack scheme,and the model of swarm antagonistic motion imitating pigeon’s intelligence is proposed to form a confrontation *** analysis of the CLPIO algorithm shows its convergence in theory and the comparison with the other four metaheuristic algorithms shows its superiority in solving the mixed Nash equilibrium ***,numerical simulation verifis that the proposed methods can provide an effective combat scheme in the set scenario.

关键词： unmanned aerial vehicle(UAV) competitive learning pigeon-inspired optimization(CLPIO) swarm antagonistic motion attack target allocation dynamic game theory

Silk fibroin sponge combined with cell-derived ECM for tissueengineered 3D functional neural tissues

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Science China(Technological Sciences) 2020年第10期63卷 2113-2122页

作者： ZHU HuiMin LIU Wei YIN Qi LI SiWei WANG ChangYong SONG Lun QIAO Xin Tissue engineering Research Center Academy of Military Medical Sciences and Department of Neural Engineering and Biological Interdisciplinary StudiesInstitute of Military Cognition and Brain SciencesAcademy of Military Medical SciencesBeijing 100850China Department of Neuroimmunology Beijing Institute of Brain SciencesBeijing 100850China

The construction of engineered neural tissue using cell-derived extracellular matrix(ECM)-modified scaffolds is a promising *** fibroin(SF)sponge is an advantageous scaffold for the construction of engineered neural tissues,but it can still be modified to enhance its *** mouse embryonic fibroblasts(MEFs)are proven that they can secrete amounts of ECM and soluble factors including neurotrophic ***-derived ECM is expected to improve the activity of the *** we aimed to construct 3D functional neural tissues based on MEFs-derived ECM modified SF *** were cultured on porous SF sponges and decellularized with Triton X-100 and *** decellularized ECM deposited scaffolds were characterized through scanning electron microscopy and confocal *** efficiency of decellularization was evaluated by quantifying remaining ***,we investigated the primary cortical neuronal growth and 3D neural network formation effect on MEFs-derived ECM modified SF *** to bare SF sponges,ECM-SF sponges showed improved neuronal growth and axon extension indicated by immunofluorescence staining and ***,ECM-SF sponges showed increased 3D neural network formation with functional ***,this study demonstrated that functionalization of SF scaffolds using cell-derived ECM could improve the bioactivity of SF materials and provide an ideal microenvironment for functional neural tissue formation.

关键词： silk fibroin cell-derived matrix tissue engineering neuron scaffold