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Finite-time Reliable Stabilization for Switched Stochastic Systems Under Asynchronous Switching

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Finite-time Reliable Stabilization for Switched Stochastic S...

Visualization analysis of the capability of weapon system of systems for multi-dimensional indicators

第25届中国控制与决策会议

作者： Wang Ronghao Qian Zhigen Xing Jianchun Wang Ping Yang Qiliang College of defense Engineering PLA University of Science and Technology pla academy of national defense information

ISBN: (纸本)9781467355339

In this paper, the finite-time stabilization problems for switched stochastic systems are addressed. Firstly, when there exists asynchronous switching between the controller and the system, a sufficient condition for the existence of stabilizing switching law for switched stochastic systems is derived. It is proved that the switched stochastic systems are finite-time stabilizable under asynchronous switching satisfying the average dwell-time condition. Furthermore, the problem of reliable control for switched stochastic systems under asynchronous switching is also investigated. Finally, a numerical example is given to illustrate the effectiveness of the proposed method.

关键词： Asynchronous Switching Switched Stochastic Systems Average Dwell-time Finite-time Reliable Control

来源： cnki会议评论

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Journal of Systems Engineering and Electronics 2017年第2期28卷 292-300页

作者： Jianfei Ding Guangya Si Guoqiang Yang Yang Liu Xiao Liu Department of information Operation & Command Training National Defense University of PLA Beijing 100091 China Graduate School National Defense University of PLA Beijing 100091 China

In the field of weapon system of systems (WSOS) simulation, various indicators are widely used to describe the capability of WSOS, but it is always difficult to describe the comprehensive capability of WSOS quickly and intuitively by visualization of multi-dimensional indicators. A method of machine learning and visualization is proposed, which can display and analyze the capabilities of different WSOS in a two-dimensional plane. The analysis and comparison of the comprehensive capability of different components of WSOS is realized by the method, which consists of six parts: multiple simulations, key indicators mining, three spatial distance calculation, fusion project calculation, calculation of individual capability density, and calculation of multiple capability ranges overlay. Binding a simulation experiment, the collaborative analysis of six indicators and 100 possible kinds of red WSOS are achieved. The experimental results show that this method can effectively improve the quality and speed of capabilities analysis, reveal a large number of potential information, and provide a visual support for the qualitative and quantitative analysis model.

关键词： weapon system of systems (WSOS) comprehensive capability visualization of multi-dimensional indicators machine learning

Construction of composite indicator system based on simulation data mining

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Journal of Systems Engineering and Electronics 2017年第1期28卷 81-87页

作者： Jianfei Ding Guangya Si Baoqiang Li Jingyu Yang Yu Zhang Department of information Operation&Command Training National Defense University of PLABeijing 100091China Graduate School of national defense University of pla Beijing 100091China

The indicator system is the foundation and emphasis in the effectiveness evaluation of system of systems(SoS). In the past, indicator systems were founded based on qualitative methods, and every indicator was mainly determined by the expert with experience. This paper proposed a brand-new method to construct indicator systems based on the repeated simulation of the scenario space, and calculated by quantitative data. Firstly, the selection of key indicators using the Gini indicator importance measure(IIM)is calculated by random forests(RFs). Then, principal component analysis(PCA) is applied when we use the selected indicators to construct the composite indicator system of SoS. Furthermore,a set of rulesare is developed to verify the practicability of the indicator system such as correlation, robustness, accuracy and convergence. Experiment shows that the algorithm achieves good results for the construction of composite indicators of So S.

关键词： system of systems(SoS) indicator system random forests(RFs) principal component analysis(PCA)

Electron–phonon coupling in topological insulator Bi_2Se_3 thin films with different substrates

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Chinese Optics Letters 2019年第2期17卷 21-24页

作者： Tian Jiang Runlin Miao Jie Zhao Zhongjie Xu Tong Zhou Ke Wei Jie You Xin Zheng Zhenyu Wang Xiang’ai Cheng College of Advanced Interdisciplinary Studies National University of Defense Technology State Key Laboratory of High Performance Computing College of Computer National University of Defense Technology Interdisciplinary Center of Quantum information National University of Defense Technology national Institute of defense Technology Innovation Academy of Military Sciences PLA China

Broadband transient reflectivity traces were measured for Bi_2 Se_3 thin films with various substrates via a 400 nm pump–white-light-probe setup. We have verified the existence of a second Dirac surface state in Bi_2 Se_3 and qualitatively located it by properly analyzing the traces acquired at different probe wavelengths. Referring to the band structure of Bi_2 Se_3, the relaxation mechanisms for photo-excited electrons with different energies are also revealed and studied. Our results show a second rise of the transient reflection signal at the time scale of several picoseconds. The types of substrate can also significantly affect the dynamics of the rising signal. This phenomenon is attributed to the effect of lattice heating and coherent phonon processes. The mechanism study in this work will benefit the fabrication of high-performance photonic devices based on topological insulators.

关键词： phonon coupling insulator films

Decoupled Two-Phase Framework for Class-Incremental Few-Shot Named Entity Recognition

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Tsinghua Science and Technology 2023年第5期28卷 976-987页

作者： Yifan Chen Zhen Huang Minghao Hu Dongsheng Li Changjian Wang Feng Liu Xicheng Lu College of Computer National University of Defense TechnologyChangsha 410073China information Research Center of Military Science PLA Academy of Military ScienceBeijing 100091China

Class-Incremental Few-Shot Named Entity Recognition(CIFNER)aims to identify entity categories that have appeared with only a few newly added(novel)class ***,existing class-incremental methods typically introduce new parameters to adapt to new classes and treat all information equally,resulting in poor ***,few-shot methods necessitate samples for all observed classes,making them difficult to transfer into a class-incremental ***,a decoupled two-phase framework method for the CIFNER task is proposed to address the above *** whole task is converted to two separate tasks named Entity Span Detection(ESD)and Entity Class Discrimination(ECD)that leverage parameter-cloning and label-fusion to learn different levels of knowledge separately,such as class-generic knowledge and class-specific ***,different variants,such as the Conditional Random Field-based(CRF-based),word-pair-based methods in ESD module,and add-based,Natural Language Inference-based(NLI-based)and prompt-based methods in ECD module,are investigated to demonstrate the generalizability of the decoupled *** experiments on the three Named Entity Recognition(NER)datasets reveal that our method achieves the state-of-the-art performance in the CIFNER setting.

关键词： named entity recognition deep learning class-incremental learning few-shot learning

Hybrid Particle Swarm Optimization Algorithm Based on Entropy Theory for Solving DAR Scheduling Problem

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Tsinghua Science and Technology 2019年第3期24卷 281-290页

作者： Haowei Zhang Junwei Xie Jiaang Ge Junpeng Shi Zhaojian Zhang Air and Missile defense College Air Force Engineering University national University of defense Technology (NUDT) Air Force Early Warning academy of pla

An efficient task-scheduling algorithm in the Digital Array Radar(DAR) is essential to ensure that it can handle a large number of requested tasks simultaneously. As a solution to this problem, in this paper, we propose an optimization model for scheduling DAR tasks using a hybrid approach. The optimization model considers the internal task structure and the DAR task-scheduling characteristic. The hybrid approach integrates a particle swarm optimization algorithm with a genetic algorithm and a heuristic task-interleaving algorithm. We introduce the chaos theory to optimize initialized particles and use entropy theory to indicate the diversity of particles and adaptively adjust the inertia weight, the crossover probability, and the mutation probability. Then, we improve both the efficiency and global exploration ability of the hybrid algorithm. In the framework of the swarm exploration algorithm, we include a heuristic task-interleaving scheduling algorithm, which not only utilizes the wait interval to transmit or receive subtasks, but also overlaps the receive intervals of different tasks. In a large-scale simulation,we demonstrate that the proposed algorithm is more robust and effective than existing algorithms.

关键词： digital array radar task scheduling particle swarm optimization

Exact mesh shape design of large cable-network antenna reflectors with flexible ring truss supports

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Acta Mechanica Sinica 2014年第2期30卷 198-205页

作者： Wang Liu Dong-Xu Li Xin-Zhan Yu Jian-Ping Jiang College of Aerospace Science and Engineering National University of Defense Technology academy of Space information System Academy of Space Electronic Information Technology

An exact-designed mesh shape with favorable surface accuracy is of practical significance to the performance of large cable-network antenna reflectors. In this study, a novel design approach that could guide the generation of exact spatial parabolic mesh configurations of such reflector was proposed. By incorporating the traditional force density method with the standard finite element method, this proposed approach had taken the deformation effects of flexible ring truss supports into consideration, and searched for the desired mesh shapes that can satisfy the requirement that all the free nodes are exactly located on the objective paraboloid. Compared with the conventional design method,a remarkable improvement of surface accuracy in the obtained mesh shapes had been demonstrated by numerical examples. The present work would provide a helpful technical reference for the mesh shape design of such cable-network antenna reflector in engineering practice.

关键词： Cable-network Mesh shape design Support deformation Force density Surface accuracy

Joint UAV trajectory and communication design with heterogeneous multi-agent reinforcement learning

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Science China(information Sciences) 2024年第3期67卷 225-245页

作者： Xuanhan ZHOU Jun XIONG Haitao ZHAO Xiaoran LIU Baoquan REN Xiaochen ZHANG Jibo WEI Hao YIN College of Electronic Science and Technology National University of Defense Technology Systems Engineering Institute Academy of Military Sciences PLA

Unmanned aerial vehicles(UAVs) are recognized as effective means for delivering emergency communication services when terrestrial infrastructures are unavailable. This paper investigates a multiUAV-assisted communication system, where we jointly optimize UAVs’ trajectories, user association, and ground users(GUs)’ transmit power to maximize a defined fairness-weighted throughput metric. Owing to the dynamic nature of UAVs, this problem has to be solved in real time. However, the problem’s non-convex and combinatorial attributes pose challenges for conventional optimization-based algorithms, particularly in scenarios without central controllers. To address this issue, we propose a multi-agent deep reinforcement learning(MADRL) approach to provide distributed and online solutions. In contrast to previous MADRLbased methods considering only UAV agents, we model UAVs and GUs as heterogeneous agents sharing a common objective. Specifically, UAVs are tasked with optimizing their trajectories, while GUs are responsible for selecting a UAV for association and determining a transmit power level. To learn policies for these heterogeneous agents, we design a heterogeneous coordinated QMIX(HC-QMIX) algorithm to train local Q-networks in a centralized manner. With these well-trained local Q-networks, UAVs and GUs can make individual decisions based on their local observations. Extensive simulation results demonstrate that the proposed algorithm outperforms state-of-the-art benchmarks in terms of total throughput and system fairness.

关键词： unmanned aerial vehicle (UAV) trajectory design resource allocation multi-agent deep reinforcement learning (MADRL) heterogeneous agents

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Interactive Details on Demand Visual Analysis on Large Attributed Networks

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Chinese Journal of Electronics 2018年第5期27卷 900-909页

作者： DU Xiaolei WEI Yingmei WU Lingda College of information System and Management National University of Defense Technology The Key Laboratory of the academy of Equipment Equipment Academy

Increasing scale leaves a challenging problem for visualizing large attributed networks. This paper proposes a details on demand approach for exploratory visual analysis on large attributed networks. Ma jor structures are located and emphasized at each level, providing clues for user observation. The detailed subnet structure emerges gradually through the exploration *** method dynamically aggregates network with consideration of both structural and attribute properties. It allows a flexible control of the hierarchy structure. A userspecified interaction strategy is introduced to enable users to customize the analysis flow according to different analytic tasks. Case studies demonstrate that the proposed method is effective in extracting global knowledge, locating ma jor structures, and discovering hidden information in networks.

关键词： Large attributed networks Visual analytics Content-based approach Details on demand