Wireless Sensor Network(WSN)is widely utilized in large-scale distributed unmanned detection scenarios due to its low cost and flexible installation.However,WSN data collection encounters challenges in scenarios lacki...Wireless Sensor Network(WSN)is widely utilized in large-scale distributed unmanned detection scenarios due to its low cost and flexible installation.However,WSN data collection encounters challenges in scenarios lacking communication infrastructure.Unmanned aerial vehicle(UAV)offers a novel solution for WSN data collection,leveraging their high mobility.In this paper,we present an efficient UAV-assisted data collection algorithm aimed at minimizing the overall power consumption of the WSN.Firstly,a two-layer UAV-assisted data collection model is introduced,including the ground and aerial layers.The ground layer senses the environmental data by the cluster members(CMs),and the CMs transmit the data to the cluster heads(CHs),which forward the collected data to the UAVs.The aerial network layer consists of multiple UAVs that collect,store,and forward data from the CHs to the data center for analysis.Secondly,an improved clustering algorithm based on K-Means++is proposed to optimize the number and locations of CHs.Moreover,an Actor-Critic based algorithm is introduced to optimize the UAV deployment and the association with CHs.Finally,simulation results verify the effectiveness of the proposed algorithms.展开更多
针对无人机在空战过程中的自主决策问题,以无人机1v1攻防为背景提出了无人机近距空战模型。采用Markov决策过程建立了无人机自主机动模型,提出基于Soft Actor Critic (SAC)算法的无人机自主空战决策算法,以无人机空战态势数据作为输入,...针对无人机在空战过程中的自主决策问题,以无人机1v1攻防为背景提出了无人机近距空战模型。采用Markov决策过程建立了无人机自主机动模型,提出基于Soft Actor Critic (SAC)算法的无人机自主空战决策算法,以无人机空战态势数据作为输入,输出无人机机动指令,使得无人机通过完成指定指令,率先锁定敌方无人机并抢先攻击。最后,设计仿真实验,通过对比双延迟深度确定性策略梯度(Twin Delayed Deep Deterministic Policy Gradient Algorithm, TD3)算法,验证了基于SAC算法的无人机空战决策算法在增强策略探索的情况下,学习速度大幅度提高,使无人机在任意初始态势下主动占据优势,并成功打击目标,有效提高了无人机在空战决策过程中的自主性。展开更多
Advertising becomes indispensable in modern times due to its wide influence on consumers and it is presented in formsof various media including newspapers, radio and television, etc. Advertisement, with its visual and...Advertising becomes indispensable in modern times due to its wide influence on consumers and it is presented in formsof various media including newspapers, radio and television, etc. Advertisement, with its visual and verbal features, is often studiedby many scholars from a linguistic perspective. This article will compare two print advertisements in magazines targeting males andfemales respectively in terms of gendered social actors regarding multimodality and intertextuality.展开更多
针对现代空战中的无人机自主决策问题,将注意力机制(AM)与深度强化学习中的非确定性策略算法Soft Actor Critic(SAC)相结合,提出一种基于AM-SAC算法的机动决策算法。在1V1的作战背景下建立无人机3自由度运动模型和无人机近距空战模型,...针对现代空战中的无人机自主决策问题,将注意力机制(AM)与深度强化学习中的非确定性策略算法Soft Actor Critic(SAC)相结合,提出一种基于AM-SAC算法的机动决策算法。在1V1的作战背景下建立无人机3自由度运动模型和无人机近距空战模型,并利用敌我之间相对距离和相对方位角构建导弹攻击区模型。将AM引入SAC算法,构造权重网络,从而实现训练过程中奖励权重的动态调整并设计仿真实验。通过与SAC算法的对比以及在多个不同初始态势环境下的测试,验证了基于AM-SAC算法的机动决策算法具有更高的收敛速度和机动稳定性,在空战中有更好的表现,且适用于多种不同的作战场景。展开更多
This paper describes a real-time beam tuning method with an improved asynchronous advantage actor–critic(A3C)algorithm for accelerator systems.The operating parameters of devices are usually inconsistent with the pre...This paper describes a real-time beam tuning method with an improved asynchronous advantage actor–critic(A3C)algorithm for accelerator systems.The operating parameters of devices are usually inconsistent with the predictions of physical designs because of errors in mechanical matching and installation.Therefore,parameter optimization methods such as pointwise scanning,evolutionary algorithms(EAs),and robust conjugate direction search are widely used in beam tuning to compensate for this inconsistency.However,it is difficult for them to deal with a large number of discrete local optima.The A3C algorithm,which has been applied in the automated control field,provides an approach for improving multi-dimensional optimization.The A3C algorithm is introduced and improved for the real-time beam tuning code for accelerators.Experiments in which optimization is achieved by using pointwise scanning,the genetic algorithm(one kind of EAs),and the A3C-algorithm are conducted and compared to optimize the currents of four steering magnets and two solenoids in the low-energy beam transport section(LEBT)of the Xi’an Proton Application Facility.Optimal currents are determined when the highest transmission of a radio frequency quadrupole(RFQ)accelerator downstream of the LEBT is achieved.The optimal work points of the tuned accelerator were obtained with currents of 0 A,0 A,0 A,and 0.1 A,for the four steering magnets,and 107 A and 96 A for the two solenoids.Furthermore,the highest transmission of the RFQ was 91.2%.Meanwhile,the lower time required for the optimization with the A3C algorithm was successfully verified.Optimization with the A3C algorithm consumed 42%and 78%less time than pointwise scanning with random initialization and pre-trained initialization of weights,respectively.展开更多
This paper analyzes the actor's lines to reveal the characterization of the hero Marlin in the animation Finding Nemo from a pragmatic perspective by applying conversational implicature and cooperative principle,e...This paper analyzes the actor's lines to reveal the characterization of the hero Marlin in the animation Finding Nemo from a pragmatic perspective by applying conversational implicature and cooperative principle,especially the violations of maxims of cooperative principle.From the analysis we can see how individualized language is created by the violation of maxims and how individualized language vividly creates characters.This paper gives a totally new perspective to appreciate this stunning animation.展开更多
In recent years, the development of wireless sensor networks(WSNs) has risen to a great interest in the Wireless Sensor and Actor Networks(WSANs), which consist of sensors and actors. Because actors have to collaborat...In recent years, the development of wireless sensor networks(WSNs) has risen to a great interest in the Wireless Sensor and Actor Networks(WSANs), which consist of sensors and actors. Because actors have to collaborate with each other to perform tasks, it is vital to maintain the connectivity of actor network in WSANs. This paper proposes a 1-hop based cut-vertex independent connectivity maintaining approach(CIMA) to restore the broken connectivity caused by single actor failure. A balance is achieved in restoration overheads between all actors and individuals by bounding the maximum moveable distance of actor and determining a local optimal repair plan. The effectiveness of CIMA has been validated through simulation experiments.展开更多
基金supported by the National Natural Science Foundation of China(NSFC)(61831002,62001076)the General Program of Natural Science Foundation of Chongqing(No.CSTB2023NSCQ-MSX0726,No.cstc2020jcyjmsxmX0878).
文摘Wireless Sensor Network(WSN)is widely utilized in large-scale distributed unmanned detection scenarios due to its low cost and flexible installation.However,WSN data collection encounters challenges in scenarios lacking communication infrastructure.Unmanned aerial vehicle(UAV)offers a novel solution for WSN data collection,leveraging their high mobility.In this paper,we present an efficient UAV-assisted data collection algorithm aimed at minimizing the overall power consumption of the WSN.Firstly,a two-layer UAV-assisted data collection model is introduced,including the ground and aerial layers.The ground layer senses the environmental data by the cluster members(CMs),and the CMs transmit the data to the cluster heads(CHs),which forward the collected data to the UAVs.The aerial network layer consists of multiple UAVs that collect,store,and forward data from the CHs to the data center for analysis.Secondly,an improved clustering algorithm based on K-Means++is proposed to optimize the number and locations of CHs.Moreover,an Actor-Critic based algorithm is introduced to optimize the UAV deployment and the association with CHs.Finally,simulation results verify the effectiveness of the proposed algorithms.
文摘Advertising becomes indispensable in modern times due to its wide influence on consumers and it is presented in formsof various media including newspapers, radio and television, etc. Advertisement, with its visual and verbal features, is often studiedby many scholars from a linguistic perspective. This article will compare two print advertisements in magazines targeting males andfemales respectively in terms of gendered social actors regarding multimodality and intertextuality.
文摘针对现代空战中的无人机自主决策问题,将注意力机制(AM)与深度强化学习中的非确定性策略算法Soft Actor Critic(SAC)相结合,提出一种基于AM-SAC算法的机动决策算法。在1V1的作战背景下建立无人机3自由度运动模型和无人机近距空战模型,并利用敌我之间相对距离和相对方位角构建导弹攻击区模型。将AM引入SAC算法,构造权重网络,从而实现训练过程中奖励权重的动态调整并设计仿真实验。通过与SAC算法的对比以及在多个不同初始态势环境下的测试,验证了基于AM-SAC算法的机动决策算法具有更高的收敛速度和机动稳定性,在空战中有更好的表现,且适用于多种不同的作战场景。
文摘This paper describes a real-time beam tuning method with an improved asynchronous advantage actor–critic(A3C)algorithm for accelerator systems.The operating parameters of devices are usually inconsistent with the predictions of physical designs because of errors in mechanical matching and installation.Therefore,parameter optimization methods such as pointwise scanning,evolutionary algorithms(EAs),and robust conjugate direction search are widely used in beam tuning to compensate for this inconsistency.However,it is difficult for them to deal with a large number of discrete local optima.The A3C algorithm,which has been applied in the automated control field,provides an approach for improving multi-dimensional optimization.The A3C algorithm is introduced and improved for the real-time beam tuning code for accelerators.Experiments in which optimization is achieved by using pointwise scanning,the genetic algorithm(one kind of EAs),and the A3C-algorithm are conducted and compared to optimize the currents of four steering magnets and two solenoids in the low-energy beam transport section(LEBT)of the Xi’an Proton Application Facility.Optimal currents are determined when the highest transmission of a radio frequency quadrupole(RFQ)accelerator downstream of the LEBT is achieved.The optimal work points of the tuned accelerator were obtained with currents of 0 A,0 A,0 A,and 0.1 A,for the four steering magnets,and 107 A and 96 A for the two solenoids.Furthermore,the highest transmission of the RFQ was 91.2%.Meanwhile,the lower time required for the optimization with the A3C algorithm was successfully verified.Optimization with the A3C algorithm consumed 42%and 78%less time than pointwise scanning with random initialization and pre-trained initialization of weights,respectively.
文摘This paper analyzes the actor's lines to reveal the characterization of the hero Marlin in the animation Finding Nemo from a pragmatic perspective by applying conversational implicature and cooperative principle,especially the violations of maxims of cooperative principle.From the analysis we can see how individualized language is created by the violation of maxims and how individualized language vividly creates characters.This paper gives a totally new perspective to appreciate this stunning animation.
基金supported by the National Science Foundation, China, contract #61163064
文摘In recent years, the development of wireless sensor networks(WSNs) has risen to a great interest in the Wireless Sensor and Actor Networks(WSANs), which consist of sensors and actors. Because actors have to collaborate with each other to perform tasks, it is vital to maintain the connectivity of actor network in WSANs. This paper proposes a 1-hop based cut-vertex independent connectivity maintaining approach(CIMA) to restore the broken connectivity caused by single actor failure. A balance is achieved in restoration overheads between all actors and individuals by bounding the maximum moveable distance of actor and determining a local optimal repair plan. The effectiveness of CIMA has been validated through simulation experiments.
