一种多帆器人协作围捕策略的研究

在二维受限环境中,研究多机器人对移动目标的协作围捕问题,结合追捕者与逃逸者的相对位姿,对多机器人围捕的初始状态条件进行划分,针对多机器人群体规模、速度、成功围捕条件进行讨论,并对目标机器人的逃逸策略和围捕机器人的围捕策略进行协调性动态调整,提出了采用夹角最大原则的逃逸策略,确定了迎面对角阻截与虚拟势点相结合的围捕策略。课题对分别将新提出的逃逸策略和围捕策略与原有逃逸策略和围捕策略相比较进行仿真实验,结果表明所提出的动态调整策略的有效性。     

基于模糊控制协调策略的多自主机器人围捕

为了降低多机器入围捕中的通信量,提高多机器人系统对未知环境的适应性,提出了一种基于模糊控制协调策略的多自主机器入围捕方法.围捕机器人根据感知范围内同伴和目标的分布,从L模糊控制器、R模糊控制器和M模糊控制器中选取合适的一个用以控制和最邻角同伴之间的夹角,进而实现多机器人之间的局部协调,结合基于局部感知的目标跟踪,在围捕...     

一种多移动机器人协作围捕策略

提出一种在连续未知环境中实现多移动机器人协作围捕移动目标的整体方案.围捕包括包围目标和靠近目标,包围目标行为由强化学习算法实现.用状态聚类减小状态空间,利用Q学习算法获得Q值表,根据学习后的Q值表选择动作.对各种行为的输出进行加权求和获得综合行为,实现对移动目标的围捕.仿真实验获得了在不同条件下的围捕结果.结果表明,环境、hunter与prey的速度关系以及prey的逃跑策略对围捕效果都有影响.     

基于共识主动性的群体机器人目标搜索与围捕

群体机器人系统的目标搜索和围捕任务是智能机器人领域一个典型的复杂问题,大多数现有的解决这一问题的方法依赖于一些不现实的假设,如可靠的通信链接、全局坐标信息、已知的环境信息以及机器人之间的中央协调控制. 为此,本文提出了一种基于共识主动性的群体机器人目标搜索与围捕框架. 该框架对反蚁群算法进行了改进,加入了多种信息素来帮助群体机器人协作探索环境,并生成信息素地图. 同时,该框架把在前一阶段生成的信息素地图和分层基因调控网络(hierarchical gene regulatory network,H-GRN)模型相结合,完成了群体机器人在环境信息未知且通信受限的场景中对动态目标的搜索和围捕任务. 仿真实验表明,该方法相较于传统方法具有更好的性能表现.      

多机器人围捕的人工力矩方法

针对多机器人协作围捕问题,提出了一种基于人工力矩的自组织方法.给出了个体机器人的自由运动模型的数学描述和同盟、围捕曲线、吸引点的概念,并且围捕者根据局部信息对吸引点进行了适当的调整.同时设计了围捕者和入侵者的人工力矩运动控制器,使得围捕者在仅知道局部信息的情况下也能相互协调并最终形成理想的围捕队形.最后用Matlab仿真,结果表明,本文给出的自组织围捕方法是行之有效的.     

合作围捕移动机器人小队中机器人的反馈控制

本文介绍了一种反馈控制方法来协调多主体移动机器人围捕一个目标,并重点讨论了对机器人的反馈控制及稳定性.     

面向多机协同的Att-MADDPG围捕控制方法设计

多无人机对动态目标的围捕是无人机集群作战中的重要问题.针对面向动态目标的集群围捕问题,通过分析基于MADDPG算法的围捕机制的不足,借鉴Google机器翻译团队使用的注意力机制,将注意力机制引入围捕过程,设计基于注意力机制的协同围捕策略,构建了相应的围捕算法.基于AC框架对MAD-DPG进行改进,首先,在Critic网络加入Attention模块,依据不同注意力权重对所有围捕无人机进行信息处理;然后,在Actor网络加入Attention模块,促使其他无人机进行协同围捕.仿真实验表明,Att-MAD-DPG算法较MADDPG算法的训练稳定性提高8.9％,任务完成耗时减少19.12％,经学习后的围捕无人机通过协作配合使集群涌现出更具智能化围捕行为.     

编者按

针对多无人机对入侵飞行器的协同追踪围捕控制问题,将自然界中生物群落在捕捉猎物时展现的逃逸-围捕策略引入到多无人机协同作战研究中,设计了一种多无人机协同围捕逃逸目标策略.该策略由2个阶段组成,第1阶段使用基于动态反馈线性化的控制方法准确跟踪逃逸目标,第2阶段使用李雅普诺夫矢量场方法.该方法可以保障多无人机在围捕飞行中躲避敌方防空力量、雷达探测等危险区域.仿真结果验证了所设计的策略在多无人机围捕和阻止目标逃逸场景中的可行性与有效性.     

七自由度球头开孔机器人结构优化研究

为解决某装备球头开孔作业存在的问题,提出了一套七自由度串联开孔机器人设备方案,根据其D-H运动学模型进行运动学分析并检验了机器人的工作空间.根据机器人的静刚度、速度以及最大工作空间距离指标,构建了机器人的多目标尺寸优化模型;利用少控制参数的多目标粒子群优化算法对模型进行求解.最终结果表明,在取前臂尺寸为0.958m,后臂尺寸为0.965m时,相较于尺寸优化前,机器人的静刚度全域指标提升了60.05%,速度综合全域指标提高了3.1%,最大工作空间距离指标增加了6.4%.     

一种移动机器人跟踪机动目标的方法

针对机器人跟踪机动目标,提出了一种完整探测、估计的方法.利用单目视觉定位被跟踪目标的方位,再融合激光数据来获取目标的空间位置.基于"当前"统计模型,将获取到空间位置作为观测信息,采用自适应卡尔曼滤波算法,对机动目标进行跟踪,并准确预测其位置、速度及加速度信息.为验证本方案,使用一个Pioneer 3-AT作为主动机器人,及一个AmigoBot机器人作为被跟踪目标进行实验.结果显示,提议的方案可行,其精度满足实际应用的要求.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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Brief Introduction to “Journal of Jilin University( Science Edition) ”

<正>"Journal of Jilin University(Science Edition)"is a comprehensive academic journal in the fields of science sponsored by Jilin University and administrated by the Ministry of Education of the Peoples Republic of China.The journal started publication in 1955.The original name at starting publication was"Journal of Natural Science of Northeast People University",which was changed into"Acta Scientiarum Naturalium Universitatis Jilinensis"in 1958 owing to the name change of the university.The present journal name has