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UAV swarm air combat maneuver decision-making method based on multi-agent reinforcement learning and transferring

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Science China(Information Sciences) 2024年第8期67卷 49-66页

作者： Zhiqiang ZHENG chen WEI Haibin duan State Key Laboratory of Virtual Reality Technology and Systems School of Automation Science and Electrical Engineering Beihang University

During short-range air combat involving unmanned aircraft vehicle(UAV) swarms, UAVs must make accurate maneuver decisions based on information from both enemy and friendly UAVs. This dual requirement of competition and cooperation presents a significant challenge in the field of unmanned air combat. In this paper, a method based on multi-agent reinforcement learning(MARL) is proposed to address this issue. An actor network containing three subnetworks that can handle different types of situational information is designed. Hence, the results from simpler one-on-one scenarios are leveraged to enhance the complex swarm air combat training process. Separate state spaces for local and global information are designed for the actor and critic networks. A detailed reward function is proposed to encourage *** prevent lazy participants in air combat, a reward assignment operation is applied to distribute these dense rewards. Simulation testing and ablation experiments demonstrate that both the transfer operation and reward assignment operation can effectively deal with the swarm air combat scenario, and reflect the effectiveness of the proposed method.

关键词： UAV swarm short-range air combat multi-agent reinforcement learning reward assignment transfer

Design, modeling, and evaluation of parallel continuum robots: A survey

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Science China(Technological Sciences) 2024年第3期67卷 673-695页

作者： chen GenLiang TANG ShuJie duan XuYang WANG Hao Meta Robotics Institute Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Mechanical Systems and Vibration Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Laboratory of Digital Manufacturing for Thin-Walled Structures Shanghai Jiao Tong UniversityShanghai 200240China

Parallel continuum robots(PCRs) have attracted increasing attention in the robotics community due to their simplicity in structure,inherence with compliance, and easiness of realization. Over the past decade, a variety of novel designs have been reported to enrich their diversity. However, there is a lack of systematic review of these emerging robots. To this end, this paper conducts a comprehensive survey on the mechanism design, kinetostatic modeling and analysis, and performance evaluation. For these robots, kinetostatic modeling plays a fundamental role throughout the design, analysis, and control stages. A systematic review of the existing approaches for kinetostatic modeling and analysis is provided, and a comparison is made to distinguish their differences. As well, a classification is made according to the characteristics of structure and actuation. In addition, performance evaluation on the workspace, stability, and singularity is also overviewed. Finally, the scenarios of potential applications are elaborated, and future research prospects are discussed. We believe that the information provided in this paper will be particularly useful for those who are interested in PCRs.

关键词： parallel continuum robots classification kinetostatic modeling performance evaluation

Application Analysis of Multiple Neurons Connected with Fast Inhibitory Synapses

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Journal of Bionic Engineering 2024年第4期21卷 1905-1918页

作者： Wen duan Weihai chen Jianhua Wang Zhongcai Pei Jingmeng Liu Jianer chen School of Automation Science and Electrical Engineering Beihang UniversityXueyuan RoadBeijing100191China Hangzhou Innovation Institute Beihang UniversityChuanghui StreetHangzhou310051ZhejiangChina School of Electrical Engineering and Automation Anhui UniversityAnhui230601ZhejiangChina Zhejiang Rehabilitation Medical Center Binsheng RoadHangzhou310052ZhejiangChina

Almost all living organisms exhibit autonomic oscillatory activities,which are primarily generated by the rhythmic activities of their neural *** nonlinear oscillator models have been proposed to elucidate these neural behaviors and subsequently applied to the domain of robot ***,the oscillation patterns generated by these models are often unpredictable and need to be obtained through parameter *** study introduces a mathematical model that can be used to analyze multiple neurons connected through fast inhibitory *** characteristic of this oscillator is that its stationary point is stable,but the location of the stationary point changes with the system *** through reasonable topology and threshold parameter selection can the oscillation be *** study analyzed the conditions for stable oscillation in two-neuron networks and three-neuron networks,and obtained the basic rules of the phase relationship of the oscillator network established by this *** addition,this study also introduces synchronization mechanisms into the model to enable it to be synchronized with the sensing ***,this study used these theories to establish a robot single leg joint angle generation *** experimental results showed that the simulated robot could achieve synchronization with human motion,and had better control effects compared to traditional oscillators.

关键词： Oscillator Phase trajectory Synaptic threshold Synchronization Motion generation

基于自发辐射分析的高碱煤燃烧炉内在线监测技术研究进展

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热力发电 2024年第1期53卷 24-37页

作者：陈装黄华汉傅勇强李华鸿方顺利王志超陈端张冲王浩帆马帅姚斌娄春湛江中粤能源有限公司广东湛江524000 西安热工研究院有限公司陕西西安710054 华中科技大学煤燃烧国家重点实验室湖北武汉430074

准东煤等高碱煤在新疆地区储量巨大,但其富含的碱金属元素极易导致炉膛受热面沾污、结渣等问题,会影响锅炉运行的安全性,研发高碱煤高效清洁燃烧发电技术对实现“双碳”目标有重要意义。总结了基于自发辐射分析的高碱煤燃烧炉内在线监... 详细信息

准东煤等高碱煤在新疆地区储量巨大,但其富含的碱金属元素极易导致炉膛受热面沾污、结渣等问题,会影响锅炉运行的安全性,研发高碱煤高效清洁燃烧发电技术对实现“双碳”目标有重要意义。总结了基于自发辐射分析的高碱煤燃烧炉内在线监测技术的研究进展,重点介绍了发射光谱技术、自发辐射图像处理及成像技术在高碱煤燃烧监测领域的研究现状及应用情况,进而对其发展趋势和动态进行探讨。发射光谱技术通过对火焰发出的不同波长光谱辐射信号进行处理获取温度与组分,近期,已广泛用于测量工业炉膛燃烧火焰温度和气相碱金属质量浓度,并基于此对炉内结渣趋势进行定性判断。自发辐射图像处理及成像技术具备信号空间分布的解析能力,利用CCD、CMOS等面阵传感器获取炉内自发辐射图像,基于图像处理与热辐射成像原理,结合辐射反问题求解方法,可以获得燃烧场在三维空间的温度分布以及二维壁温分布,使结渣的三维可视化监测成为可能。未来需基于发射光谱技术、自发辐射图像处理及成像技术对二维或者三维的受热面结渣沾污进行监测,结合炉内燃烧温度与气相碱金属质量浓度等参数分布,建立高碱煤燃烧受热面结渣沾污的定量判断指标,最终达到对受热面结渣沾污在线预测的目标。

关键词：高碱燃料自发辐射分析火焰发射光谱图像处理热辐射成像

1000 MW水轮机转轮径向安装偏差对流动特征的影响

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水力发电学报 2024年第5期43卷 35-42页

作者：吴思源王一凡刘兴民黄星星杜清玭周凌九陈端王正伟中国三峡建工(集团)有限公司四川宁南615400 中国农业大学水利与土木工程学院北京100083 瑞华智慧能源有限公司瑞士苏黎世8706 北京市供水管网系统安全与节能工程技术中心北京100083 清华大学能源与动力工程系北京100084 清华大学水圈科学与水利工程全国重点实验室北京100084

本文以百万千瓦混流机组为研究对象,使用ANSYS软件进行三维全流道稳态数值分析。探究在额定工况下,当转轮出现Y轴负方向0.1 mm、0.3 mm、0.5 mm、1.5 mm、2.5 mm的径向安装偏差时,间隙分布不均匀对于百万千瓦大型水轮机组内部流动特征... 详细信息

本文以百万千瓦混流机组为研究对象,使用ANSYS软件进行三维全流道稳态数值分析。探究在额定工况下,当转轮出现Y轴负方向0.1 mm、0.3 mm、0.5 mm、1.5 mm、2.5 mm的径向安装偏差时,间隙分布不均匀对于百万千瓦大型水轮机组内部流动特征的影响。研究发现,在一定偏差数值内,随着间隙的减小,该区域压力逐渐上升,但超过该数值以后,流体无法流入则变为了低压区。另外,上冠腔和下环腔均出现了相同数量的旋涡演变周期,但旋涡的发生位置不同,上冠腔旋涡较剧烈,且数量与叶片数呈非整数倍关系。最后阐明了下环腔内壁面受到的旋涡流动冲击程度要大于上冠腔内壁面。因此,本研究可以应用于其他大中型混流式水轮机的设计与安装,对于提高水轮机运行质量、降低运行成本和提高水电站效益具有重要意义。

关键词：百万千瓦转轮混流式机组径向安装偏差流动特征计算流体力学

All-optical 2R regeneration based on self-induced polarization rotation in a single semiconductor optical amplifier

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Chinese Science Bulletin 2009年第20期54卷 3704-3708页

作者： duan PinXiang chen LiGong ZHANG ShangJian ZHOU XiaoLi LIU YongZhi LIU Yong Key Laboratory of Broadband Optical Fiber Transmission & Communication Networks Ministry of Education School of Optoelectronic Information University of Electronic Science & Technology of China Chengdu 610054 China

An all-optical 2R regeneration based on self-induced polarization rotation in a single semiconductor optical amplifier is presented.A theoretical model is built up to simulate the system *** evidence is also *** extinction ratio improvement of 8.3 dB is obtained at a bitrate of 10 Gbit/*** the BER measurements,6 dB improvement of the power penalty is achieved,clearly demonstrating the feasibility of the proposed *** approach has a simple structure,and allows photonic integration.

关键词：半导体光放大器偏振旋转再生器诱导基础全光模拟系统功率代价

Swelling of Spherical Polyelectrolyte Gels

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Chinese Journal of Polymer Science 2024年第9期42卷 1386-1392,I0009页

作者： Ming-Yu duan Jia-Dong chen Yi-Ming Liu Zhao-Feng Peng Guang chen Department of Advanced Manufacturing and Robotics College of EngineeringPeking UniversityBeijing 100871China

Polyelectrolyte(PE)gels,distinguished by their unique stimuli-responsive swelling behavior,serve as the basis of broad applications,such as artificial muscles and drug *** this work,we present a theoretical model to analyze the electrostatics and its contribution to the swelling behavior of PE gels in salt *** minimizing the free energy of PE gels,we obtain two distinct scaling regimes for the swelling ratio at equilibrium with respect to the salt *** compare our predictions for the swelling ratio with experimental measurements,which show excellent *** addition,we employ a finite element method to assess the applicability range of our theoretical model and *** anticipate that our model will also provide valuable insights into drug adsorption and release,deformation of red blood cells,4D printing and soft robotics,where the underlying mechanism of swelling remains enigmatic.

关键词： Gels Polyelectrolytes Swelling Stimuli-responsive Electrostatic interaction Cell model

滑车击打成形联合髌骨远近端重排治疗固定性髌骨外脱位的临床研究

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中国中医骨伤科杂志 2024年第3期32卷 83-87页

作者：李长树李政段晨欧传双丁茜李伟深圳平乐骨伤科医院(深圳市坪山区中医院) 广东深圳518010 中山大学孙逸仙纪念医院

目的:探讨股骨滑车击打成形联合髌骨远近端重排(外侧髌股韧带松解、内侧髌股韧带重建、胫骨结节内移)治疗固定性髌骨外脱位伴严重股骨滑车发育不良的临床疗效。方法:回顾性分析2019年1月至2022年1月诊断为固定性髌骨外脱位伴严重股骨滑... 详细信息

目的:探讨股骨滑车击打成形联合髌骨远近端重排(外侧髌股韧带松解、内侧髌股韧带重建、胫骨结节内移)治疗固定性髌骨外脱位伴严重股骨滑车发育不良的临床疗效。方法:回顾性分析2019年1月至2022年1月诊断为固定性髌骨外脱位伴严重股骨滑车发育不良13例患者的临床资料,其中男6例,女7例;平均年龄为(22.9±1.2)岁。均进行了股骨滑车击打成形联合髌骨远近端重排治疗,通过比较手术前后X线、CT测量股骨滑车沟角(SA)、适合角(CA)、髌骨侧方移位度(LD)、胫骨结节与股骨滑车沟距离(TT-TG)、Caton-Deschamps指数(评估高低位髌骨)、Lysholm膝关节功能评分与Kujala髌股关节不稳症状评分来评估其临床疗效。结果:本组患者均获得随访,随访时间为1~3年,平均为(1.6±0.2)年,术后伤口均Ⅰ期愈合,未发生感染、血管神经损伤等并发症,术后患者生活质量明显改善,未再次出现患肢髌骨脱位;术后1年MRI未见明显股骨滑车软骨损伤、脱落、坏死等现象,术后1年X线、CT测量股骨滑车沟角、适合角、髌骨侧方移位度、胫骨结节与股骨滑车沟距离及Caton-Deschamps指数均恢复到正常范围,与术前比较明显降低,差异有统计学意义(P<0.05)。术后1年患肢功能Lysholm膝关节功能评分从术前的(54.60±5.22)分增加到(82.60±2.70)分,Kujala髌股关节不稳症状评分从术前的(54.20±8.04)分增加到术后的(81.60±3.97)分,差异有统计学意义(P<0.05)。结论:针对固定性髌骨外脱位伴严重滑车发育不良的患者,采用股骨滑车击打成形可以重建股骨滑车沟,手术操作简单;联合髌骨远近端重排,可纠正髌股关节的运动轨迹,改善膝关节功能,中短期临床疗效良好,值得进一步推广应用。

关键词：滑车击打成形固定性髌骨外脱位股骨滑车发育不良髌骨远近端重排

Particle distributions in Lamb wave based acoustofluidics

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Nanotechnology and Precision Engineering 2024年第2期7卷 60-68页

作者： Chuanchao Zhang Xian chen Wei Wei Xuejiao chen Quanning Li Xuexin duan Key Laboratory of Precision Measuring Technology and Instruments College of Precision Instrument and Optoelectronics EngineeringTianjin UniversityTianjin300072China

Acoustic streaming enabled by a Lamb wave resonator(LWR)is efficient for particle trapping and enrichment in microfluidic ***,because Lamb waves combine the features of bulk acoustic waves and surface acoustic waves,the resulting acoustic streaming in the LWR occurs in multiple planes,and the particle flow behavior in this acoustofluidic system is largely *** here are numerical simulations and laboratory experiments conducted to investigate the boundary conditions for particle motion inside a microvortex induced by an *** dynamic capture,the particles’trajectories become orbital paths within an acoustic *** suspended particles encounter two distinct acoustic phenomena,i.e.,the drag force resulting from acoustic streaming and the acoustic radiation force,which exert forces in various directions on the *** the acoustic radiation force and the fluid drag force are dominant for large and small particles in a mixed solution,respectively,the large particles reside within the vortex while the small particles remain at its ***,when the acoustic radiation force is dominant for both types of particles,the distribution pattern is reversed.

关键词： Acoustofluidics Lamb wave resonator Particle manipulation Microvortex