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

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 {1. 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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Anti-explosion performance and dynamic response of an innovative multi-layer composite explosion containment vessel

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Defence technology（防务技术） 2024年第6期36卷 105-121页

作者： Zhen Wang Heng Chen Qi Yuan Wenbin Gu Xingbo Xie Hongwei Li college of Field Engineering Army Engineering University of PLANanjing 210007China college of Civil Engineering and Architecture Southwest University of Science and TechnologySichuanMianyang 621010China

An innovative multi-layer composite explosion containment vessel(CECV)utilizing a sliding steel platealuminum honeycomb-fiber cloth sandwich is put forward to improve the anti-explosion capacity of a conventional single-layer explosion containment vessel(SECV).Firstly,a series of experiments and finite element(FE)simulations of internal explosions are implemented to understand the basic anti-explosion characteristics of a SECV and the rationality of the computational models and methods is verified by the comparison between the experimental results and simulation *** on this,the CECV is designed in detail and a variety of FE simulations are carried out to investigate effects of the sandwich structure,the explosive quantity and the laying mode of the fiber cloth on anti-explosion performance and dynamic response of the CECV under internal *** results indicate that the end cover is the critical position for both the SECV and *** maximum pressure of the explosion shock wave and the maximum strain of the CECV can be extremely declined compared to those of the *** a result,the explosive quantity the CECV can sustain is up to 20 times of that the SECV can ***,as the explosive quantity increases,the internal pressure of the CECV keeps growing and the plastic deformation and failure of the sandwich structure become more and more severe,yielding plastic strain of the CECV in addition to elastic *** results also reveal that the laying angles of the fiber cloth's five layers have an impact on the anti-explosion performance of the *** example,the CECV with fiber cloth layered in 0°/45°/90°/45°/0°mode has the optimal anti-capacity,compared to 0°/0°/0°/0°/0°and 0°/30°/60°/30°/0°***,owing to remarkable anti-explosion capacity,this CECV can be regarded as a promising candidate for explosion resistance.

关键词： Explosive container Honeycomb-fiber cloth Anti-explosion Aluminum honeycomb core Composite

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Linear Quadratic Optimal Control for Systems Governed by First-Order Hyperbolic Partial Differential Equations

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Journal of Systems science & Complexity 2024年第1期37卷 230-252页

作者： XUE Xiaomin XU Juanjuan ZHANG Huanshui School of Control science and Engineering Shandong UniversityJinan 250061China college of Electrical Engineering and {1. Shandong University of Science and TechnologyQingdao 266000China

This paper focuses on linear-quadratic(LQ)optimal control for a class of systems governed by first-order hyperbolic partial differential equations(PDEs).Different from most of the previous works,an approach of discretization-then-continuousization is proposed in this paper to cope with the infinite-dimensional nature of PDE *** contributions of this paper consist of the following aspects:(1.The differential Riccati equations and the solvability condition of the LQ optimal control problems are obtained via the discretization-then-continuousization method.(2)A numerical calculation way of the differential Riccati equations and a practical design way of the optimal controller are ***,the relationship between the optimal costate and the optimal state is established by solving a set of forward and backward partial difference equations(FBPDEs).(3)The correctness of the method used in this paper is verified by a complementary continuous method and the comparative analysis with the existing operator results is *** is shown that the proposed results not only contain the classic results of the standard LQ control problem of systems governed by ordinary differential equations as a special case,but also support the existing operator results and give a more convenient form of computation.

关键词： Discretization-then-continuousization method first-order hyperbolic partial differential equations forward and backward partial difference equations linear quadratic optimal control.

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Bimagnetic metal constructed core-shell structure of Fe@Co nanowires for multi-band microwave absorption

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Progress in Natural science:Materials International 2024年第02期34卷 354-361页

作者： Ping-an Yang Rui Cai Haibo Ruan Nanqing Zhang Xin Huang Rui Li Yuxin Zhang Yi Lu Zhihao Zhou School of automation Chongqing University of Posts and Telecommunications Chongqing Key Laboratory of Materials Surface & Interface science Chongqing University of Arts and Sciences college of Engineering and {1. Zunyi Normal College college of Material {1. and Engineering Chongqing University

Controlled fabrication of materials by surface modification techniques has been a hot research topic. In this paper,one-dimensional(1.) core-shell structure Fe@Co nanowires(NWs) were successfully prepared by anchoring 0-dimensional(0D) Co nanoparticles on 1. Fe NWs based on the in situ reduction method. The electromagnetic parameters of the specimens at a filler mass fraction of 25 wt% were tested and the microwave loss mechanism was deeply analyzed. Binary magnetic metals in a core-shell structure have excellent multi-band microwave absorption capability(S-band, X-band and Ku-band). This is due to the heterogeneous interface and magnetic coupling effects tuning the dielectric and magnetic loss. This study offers a workable plan for creating effective multi-band magnetic metal-based microwave absorbers.

关键词： Microwave absorption One-dimensional nanowires Core-shell structure Magnetic coupling Interface

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Design of weak current measurement system and research on temperature impact

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Nuclear science and Techniques 2024年第4期35卷 46-56页

作者： Chu-Xiang Zhao San-Gang Li Rong-Rong Su Li Yang Ming-Zhe Liu Qing-Yue Xue Shan Liao Zhi Zhou Qing-Shan Tan Xian-Guo Tuo Yi Cheng college of Nuclear {1. and automation Engineering Chengdu University of Technology1#DongsanluErxianqiaoChengdu 610059China Applied Nuclear technology in Geo{1.s Key Laboratory of Sichuan Province Chengdu University of Technology1#DongsanluErxianqiaoChengdu 610059China university of {1. and technology of China Hefei 230026China School of Physics and Electronic Engineering Sichuan University of Science and EngineeringZigong 643000China

A dedicated weak current measurement system was designed to measure the weak currents generated by the neutron ionization *** system incorporates a second-order low-pass filter circuit and the Kalman filtering algorithm to effectively filter out noise and minimize interference in the measurement *** conducted under normal temperature conditions has demonstrated the system's high precision ***,it was observed that temperature variations can affect the measurement *** were collected across temperatures ranging from -20 to 70℃,and a temperature correction model was established through linear regression fitting to address this *** feasibility of the temperature correction model was confirmed at temperatures of -5 and 40℃,where relative errors remained below 0.1. after applying the temperature *** research indicates that the designed measurement system exhibits excellent temperature adaptability and high precision,making it particularly suitable for measuring weak currents.

关键词： Weak current measurement system Neutron ionization chamber Kalman filter algorithm Temperature correction model

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Fault-tolerant flocking control against multiple malicious agents under geometric configuration containment

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science China(Information sciences) 2024年第10期67卷 261-282页

作者： Chencheng ZHANG Hao YANG Bin JIANG college of {1. Engineering Nanjing University of Aeronautics and Astronautics Institute of Engineering and technology (ENTEG) University of Groningen

Flocking control in the presence of malicious decisions is a crucial research topic since agents in swarms are likely to suffer from security issues in practice. This paper considers a swarm containing malicious agents that deliberately alter their controller parameters and disrupt the swarm by causing collisions,divisions, and escapes. Two possible malicious scenarios are considered. The first is that one malicious agent acts selectively on a subset of its neighbors and the second is that multiple malicious agents are either scattered or clustered together. To achieve the flocking control objective:(1. containment conditions based on specific geometric configurations are established;(2) hierarchical fault-tolerant flocking control methods based on those containment conditions are proposed. Compared to existing research dealing with malicious agents in swarms, our approach aims to contain rather than remove them. This guarantees the completeness of the task and takes agents' motions into consideration. Simulations show the effectiveness of the proposed methods.

关键词： flocking control fault-tolerant control multiple malicious agents geometric configuration

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IQGAP3 promotes the progression of glioma as an immune and prognostic marker

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Oncology Research 2024年第4期32卷 659-678页

作者： XIAOFENG GAO JUANJUAN GE XUZHENG GAO NA MEI YANTING SU SHIGANG SHAN WENBIN QIAN JIANGHENG GUAN ZHENWANG ZHANG LONG WANG Hubei Provincial Key Laboratory of Diabetic Cardiovascular Diseases Xianning Medical CollegeHubei University of Science and TechnologyXianning437100China School of Stomatology and Ophthalmology Xianning Medical CollegeHubei University of Science and TechnologyXianning437100China School of Basic Medical sciences Xianning Medical CollegeHubei University of Science and TechnologyHubei University of Science and TechnologyXianning437100China School of Pharmacy Xianning Medical CollegeHubei University of Science and TechnologyXianning437100China Department of Neurosurgery The General Hospital of Chinese PLA Central Theater CommandWuhan430070China

Background:IQGAP3 plays a crucial role in regulating cell proliferation,division,and cytoskeletal *** expression of IQGAP3 has been linked to various tumors,but its function in glioma is not well ***:Various methods,including genetic differential analysis,single-cell analysis,ROC curve analysis,Cox regression,Kaplan-Meier analysis,and enrichment analysis,were employed to analyze the expression patterns,diagnostic potential,prognostic implications,and biological processes involving IQGAP3 in normal and tumor *** impact of IQGAP3 on immune infiltration and the immune microenvironment in gliomas was evaluated using ***,the cBioPortal database was used to analyze copy number variations and mutation sites of *** validation was also performed to assess the effects of IQGAP3 on glioma cells and explore underlying ***:High IQGAP3 expression in gliomas is associated with an unfavorable prognosis,particularly in wild-type IDH and 1./1.q non-codeleted *** analysis revealed that IQGAP3 is involved in regulating the cell cycle,PI3K/AKT signaling,p53 signaling,and PLK1.related ***,IQGAP3 expression may be closely related to the immunosuppressive microenvironment of ***-K887421.0 and LY-30351. are potential drugs for targeting IQGAP3 in anti-glioma *** vitro experiments showed that downregulation of IQGAP3 inhibits the proliferation and migration of glioma cells,with the PLK1.PI3K/AKT pathway potentially playing a crucial role in IQGAP3-mediated glioma ***:IQGAP3 shows promise as a valuable biomarker for diagnosis,prognosis,and immunotherapeutic strategies in gliomas.

关键词： IQGAP3 Tumor immune infiltration Prognosis Glioma Biomarker

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Fully distributed dynamic event-triggered formation-containment tracking for multiagent systems with multiple types of disturbances

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science China(Information sciences) 2024年第1期67卷 168-186页

作者： Weihua LI Huaguang ZHANG Juan ZHANG Rui WANG college of Information {1. and Engineering Northeastern University State Key Laboratory of Synthetical automation for Process Industries Northeastern University

This paper is dedicated to addressing the time-varying output formation-containment tracking(TVOFCT) problem for heterogeneous linear multiagent systems(MASs) with multiple types of disturbances under directed communication *** agents are divided into tracking leaders,formation leaders,and *** the output space,the formation leaders are required to form an expected geometric formation while tracking the tracking leader,and the followers are required to enter the convex hull spanned by formation ***,a disturbance observer is designed to observe the disturbance with deterministic ***,by combining adaptive technology with event-triggered technology,an independent fully distributed dynamic event-triggered(FDDET) compensator is designed to estimate the state of the tracking *** main advantages of this compensator lie in the following three aspects:(1. the adaptive weight does not increase unboundedly;(2) the interval time between events is expanded;(3) the design does not rely on any global *** to the design of this compensator,an independent FDDET convex hull observer is further designed to observe the convex hull spanned by formation ***,based on the designed disturbance observer,compensator,and convex hull observer,the adaptive disturbance rejection control input which can make the MASs achieve TVOFCT is ***,a numerical simulation is provided to clearly verify the validity of the theoretical results.

关键词： formation-containment tracking disturbance rejection multiagent systems fully distributed control dynamic event-triggered control

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Distributed adaptive resilient formation control for nonlinear multi-agent systems under DoS attacks

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science China(Information sciences) 2024年第10期67卷 391-392页

作者： Hao WEN Yongming LI Shaocheng TONG college of {1. Liaoning University of Technology

The cooperative control for multi-agent systems(MASs)with fixed topology [1.3] has been extensively studied recently. However, in practice, denial-of-service(DoS) attacks become an increasingly important issue due to... 详细信息

关键词： Directed graphs

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Multicolor circularly polarized phosphorescence of axially chiral binuclear platinum(Ⅱ) complexes

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science China Chemistry 2024年第11期67卷 3757-3766页

作者： Jintong Song Rui Zeng Hui Xiao Hailiang Ni Zong-Xiang Xu Haifeng Xiang college of Chemistry and Materials {1. Sichuan Normal University Department of Chemistry Southern University of Science and Technology college of Chemistry Sichuan University

D-A charge transfer, including through-bond charge transfer and through-space charge transfer between two different electron donors（D） and electron acceptors（A）, is a fundamental and powerful tool to tune the optical properties of organic dyes. Herein,we demonstrate a unique strategy to tune phosphorescence and circularly polarized luminescence properties of axially chiral binuclear Pt（Ⅱ） complexes through long-range charge transfer, even though these molecules have two totally identical segments on either side of the chiral core. The presence of axial chirality would break not only the symmetry of molecular structure and π-conjugation system but also the symmetry of charge distribution for long-range charge transfer. These binaphthyl-based Pt（Ⅱ）complexes bearing coordinated atoms far away from chiral axis exhibit no Pt-Pt interactions but colorful concentrationdependent phosphorescence with quantum yield up to 86.4% and could be applied as emitters in highly efficient solutionprocessed organic light-emitting diodes to achieve luminance, luminance efficiency, power efficiency, external quantum efficiency, and asymmetry factor up to 8.94 × 1.～3cd m-2, 41.9 cd A-1. 1..8 lm W-1. 1..6% and 2.98 × 1.-3, respectively. Therefore,the present work affords a new and simple way to utilize the inherently asymmetric advantage of chirality for the design of D-Abased organic dyes.

关键词： Pt(II) complexes organic light-emitting diodes circularly polarized phosphorescence axial chirality

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