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Towards intelligent and trustworthy task assignments for 5G-enabled industrial communication systems
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作者 Mingfeng Huang Anfeng Liu +1 位作者 Neal N.Xiong Athanasios V.Vasilakos 《Digital Communications and Networks》 2025年第1期246-255,共10页
With the unprecedented prevalence of Industrial Internet of Things(IIoT)and 5G technology,various applications supported by industrial communication systems have generated exponentially increased processing tasks,whic... With the unprecedented prevalence of Industrial Internet of Things(IIoT)and 5G technology,various applications supported by industrial communication systems have generated exponentially increased processing tasks,which makes task assignment inefficient due to insufficient workers.In this paper,an Intelligent and Trustworthy task assignment method based on Trust and Social relations(ITTS)is proposed for scenarios with many tasks and few workers.Specifically,ITTS first makes initial assignments based on trust and social influences,thereby transforming the complex large-scale industrial task assignment of the platform into the small-scale task assignment for each worker.Then,an intelligent Q-decision mechanism based on workers'social relation is proposed,which adopts the first-exploration-then-utilization principle to allocate tasks.Only when a worker cannot cope with the assigned tasks,it initiates dynamic worker recruitment,thus effectively solving the worker shortage problem as well as the cold start issue.More importantly,we consider trust and security issues,and evaluate the trust and social circles of workers by accumulating task feedback,to provide the platform a reference for worker recruitment,thereby creating a high-quality worker pool.Finally,extensive simulations demonstrate ITTS outperforms two benchmark methods by increasing task completion rates by 56.49%-61.53%and profit by 42.34%-47.19%. 展开更多
关键词 Industrial Internet of Things Insufficient workers Trust evaluation Social relation Task assignment
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Joint planning method for cross-domain unmanned swarm target assignment and mission trajectory
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作者 WANG Ning LIANG Xiaolong +2 位作者 LI Zhe HOU Yueqi YANG Aiwu 《Journal of Systems Engineering and Electronics》 2025年第3期736-753,共18页
Compared with single-domain unmanned swarms,cross-domain unmanned swarms continue to face new challenges in terms of platform performance and constraints.In this paper,a joint unmanned swarm target assignment and miss... Compared with single-domain unmanned swarms,cross-domain unmanned swarms continue to face new challenges in terms of platform performance and constraints.In this paper,a joint unmanned swarm target assignment and mission trajectory planning method is proposed to meet the requirements of cross-domain unmanned swarm mission planning.Firstly,the different performances of cross-domain heterogeneous platforms and mission requirements of targets are characterised by using a collection of operational resources.Secondly,an algorithmic framework for joint target assignment and mission trajectory planning is proposed,in which the initial planning of the trajectory is performed in the target assignment phase,while the trajectory is further optimised afterwards.Next,the estimation of the distribution algorithms is combined with the genetic algorithm to solve the objective function.Finally,the algorithm is numerically simulated by specific cases.Simulation results indicate that the proposed algorithm can perform effective task assignment and trajectory planning for cross-domain unmanned swarms.Furthermore,the solution performance of the hybrid estimation of distribution algorithm(EDA)-genetic algorithm(GA)algorithm is better than that of GA and EDA. 展开更多
关键词 cross-domain swarm unmanned system target assignment trajectory planning joint planning hybrid estimation of distribution algorithm(EDA)-genetic algorithm(GA)
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锻态18Cr2Ni4WA钢高温变形本构模型研究
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作者 段兴旺 贺林峰 +1 位作者 焦永星 王敏 《太原科技大学学报》 2025年第1期53-57,共5页
在Gleeble-1500热模拟试验机上,对锻态18Cr2Ni4WA钢进行单道次热压缩实验,研究了该钢的高温流变行为。通过采集数据获得了实验温度为(1123~1473)K、应变速率为(0.001~0.1)s^(-1)和变形量为55%的变形条件下的真应力-真应变曲线。以Arrhen... 在Gleeble-1500热模拟试验机上,对锻态18Cr2Ni4WA钢进行单道次热压缩实验,研究了该钢的高温流变行为。通过采集数据获得了实验温度为(1123~1473)K、应变速率为(0.001~0.1)s^(-1)和变形量为55%的变形条件下的真应力-真应变曲线。以Arrhenius本构模型为依据,并充分考虑应变对本构模型的作用,建立了应变补偿Arrhenius本构模型,用以预测其高温流变行为。结果表明:温度的降低和应变速率的增大导致锻态18Cr2Ni4WA钢的真应力增加;通过将所建立本构模型的理论预测数据与实验数据进行对比,发现吻合度较好,说明所建立的锻态18Cr2Ni4WA钢应变补偿Arrhenius本构模型具有较高的预测精度。 展开更多
关键词 锻态18Cr2Ni4wa 热压缩 本构模型 应变补偿
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淬火工艺对渗碳18Cr2Ni4WA钢采煤机行走轮冲击性能的影响
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作者 何潇 许鸿翔 +4 位作者 师陆冰 赵少甫 戎泽玉 关鹤 陈治 《金属热处理》 北大核心 2025年第3期69-73,共5页
研究了淬火工艺对18Cr2Ni4WA钢渗碳淬火采煤机行走轮冲击性能的影响,通过对18Cr2Ni4WA钢采煤机行走轮进行渗碳热处理后,再分别进行780、800、830℃油淬,最后经-60℃冷处理2 h后继续180℃回火15 h完成全部热处理工艺,热处理后对试样进行... 研究了淬火工艺对18Cr2Ni4WA钢渗碳淬火采煤机行走轮冲击性能的影响,通过对18Cr2Ni4WA钢采煤机行走轮进行渗碳热处理后,再分别进行780、800、830℃油淬,最后经-60℃冷处理2 h后继续180℃回火15 h完成全部热处理工艺,热处理后对试样进行力学性能和显微组织检测。结果表明:降低淬火温度,行走轮心部硬度明显降低,心部冲击性能大幅提升。采用亚温淬火工艺,淬火温度为780℃时,使采煤机行走轮满足表面硬度要求的同时提高心部冲击性能,显微组织由板条马氏体+铁素体+贝氏体及残留奥氏体组成,心部冲击性能大幅提升,冲击吸收能量达到108 J,实现渗碳淬火行走轮心部冲击性能的提升。 展开更多
关键词 18CR2NI4wa 行走轮 渗碳 亚温淬火 冲击性能
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18Cr2Ni4WA钢在海洋环境中的腐蚀行为
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作者 王飞 李冬冬 +2 位作者 徐新颖 邓迎诚 刘秀生 《腐蚀与防护》 北大核心 2025年第9期24-29,共6页
为了了解18Cr2Ni4WA钢在海洋环境中的腐蚀行为,对其在服役过程中的防护进行指导,进行了人造海水全浸、电化学试验、盐雾/干/湿交替循环、电偶腐蚀和实海腐蚀测试等试验。结果表明:18Cr2Ni4WA钢在人造海水中全浸1000 h的腐蚀速率为74.64... 为了了解18Cr2Ni4WA钢在海洋环境中的腐蚀行为,对其在服役过程中的防护进行指导,进行了人造海水全浸、电化学试验、盐雾/干/湿交替循环、电偶腐蚀和实海腐蚀测试等试验。结果表明:18Cr2Ni4WA钢在人造海水中全浸1000 h的腐蚀速率为74.64μm·a^(-1)。在3.5%NaCl溶液中的点蚀电位为-0.371 V,自腐蚀电位为-0.407 V,自腐蚀电流密度为1.207×10^(-6) A·cm^(-2)。盐雾/干/湿交替循环条件下1000 h后的腐蚀速率为1763.28μm·a^(-1)。其与ZCuA110Fe3钢形成对偶件,当阴阳极面积比为1∶1时,在人造海水中的腐蚀速率为237.42μm·a^(-1),电偶腐蚀系数为2.14;当阴阳极面积比为5∶1时,在人造海水中的腐蚀速率为528.33μm·a^(-1),电偶腐蚀系数为4.77。在三亚潮差带2 a实海环境测试中,对偶件中18Cr2Ni4WA钢的腐蚀速率为155.07μm·a^(-1)。实验室电偶腐蚀试验与实海对偶件腐蚀试验结果相近,能最大程度展现模拟装置在实海环境中的腐蚀规律。盐雾/干/湿交替循环试验可用于该材料在实际海洋环境中腐蚀行为的加速评价。 展开更多
关键词 18CR2NI4wa 海洋环境 腐蚀速率 电偶腐蚀 实海环境
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Disparity in immigrant compulsory care assignment: discrimination or response to treatment need
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作者 Steven P Segal Leena Badran +1 位作者 Lachlan Rimes Vinay Lakra 《General Psychiatry》 2025年第3期234-241,共8页
INTRODUCTION Reports indicating that culturally and linguistically diverse(CALD)people-often with migrant backgrounds-in Australia and New Zealand are more likely to be placed in compulsory community treatment(CCT)hav... INTRODUCTION Reports indicating that culturally and linguistically diverse(CALD)people-often with migrant backgrounds-in Australia and New Zealand are more likely to be placed in compulsory community treatment(CCT)have rightlyraised concernsthat such action might be discriminatory. 展开更多
关键词 NEED compulsory community treatment cct DISPARITY response IMMIGRANT assignment DISCRIMINATION compulsory care
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Nonlinear Interference-Aware Routing,Wavelength and Power Allocation in C+L+S Multi-Band Optical Networks
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作者 Zhang Xu Xie Wang +4 位作者 Feng Chuan Zeng Hankun Zhou Shanshan Zhang Fan Gong Xiaoxue 《China Communications》 2025年第4期129-142,共14页
Multi-band optical networks are a potential technology for increasing network capacity.However,the strong interference and non-uniformity between wavelengths in multi-band optical networks have become a bottleneck res... Multi-band optical networks are a potential technology for increasing network capacity.However,the strong interference and non-uniformity between wavelengths in multi-band optical networks have become a bottleneck restricting the transmission capacity of multi-band optical networks.To overcome these challenges,it is particularly important to implement optical power optimization targeting wavelength differences.Therefore,based on the generalized Gaussian noise model,we first formulate an optimization model for the problems of routing,modulation format,wavelength,and power allocation in C+L+S multi-band optical networks.Our objective function is to maximize the average link capacity of the network while ensuring that the Optical Signal-to-Noise(OSNR)threshold of the service request is not exceeded.Next,we propose a NonLinear Interferenceaware(NLI-aware)routing,modulation format,wavelength,and power allocation algorithm.Finally,we conduct simulations under different test conditions.The simulation results indicate that our algorithm can effectively reduce the blocking probability by 23.5%and improve the average link capacity by 3.78%in C+L+S multi-band optical networks. 展开更多
关键词 multiband optical communications multiband optical networks power allocation wavelength assignment
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Mixed integer programming modeling for the satellite three-dimensional component assignment and layout optimization problem
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作者 Yufeng XIA Xianqi CHEN +3 位作者 Zhijia LIU Weien ZHOU Wen YAO Zhongneng ZHANG 《Chinese Journal of Aeronautics》 2025年第6期427-447,共21页
Satellite Component Layout Optimization(SCLO) is crucial in satellite system design.This paper proposes a novel Satellite Three-Dimensional Component Assignment and Layout Optimization(3D-SCALO) problem tailored to en... Satellite Component Layout Optimization(SCLO) is crucial in satellite system design.This paper proposes a novel Satellite Three-Dimensional Component Assignment and Layout Optimization(3D-SCALO) problem tailored to engineering requirements, aiming to optimize satellite heat dissipation while considering constraints on static stability, 3D geometric relationships between components, and special component positions. The 3D-SCALO problem is a challenging bilevel combinatorial optimization task, involving the optimization of discrete component assignment variables in the outer layer and continuous component position variables in the inner layer,with both influencing each other. To address this issue, first, a Mixed Integer Programming(MIP) model is proposed, which reformulates the original bilevel problem into a single-level optimization problem, enabling the exploration of a more comprehensive optimization space while avoiding iterative nested optimization. Then, to model the 3D geometric relationships between components within the MIP framework, a linearized 3D Phi-function method is proposed, which handles non-overlapping and safety distance constraints between cuboid components in an explicit and effective way. Subsequently, the Finite-Rectangle Method(FRM) is proposed to manage 3D geometric constraints for complex-shaped components by approximating them with a finite set of cuboids, extending the applicability of the geometric modeling approach. Finally, the feasibility and effectiveness of the proposed MIP model are demonstrated through two numerical examples"and a real-world engineering case, which confirms its suitability for complex-shaped components and real engineering applications. 展开更多
关键词 Mixed integer programming modeling Three-dimensional component assignment Layout optimization Phi-function Finite-rectangle method
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Current development and future prospects of multi-target assignment problem:A bibliometric analysis review
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作者 Shuangxi Liu Zehuai Lin +1 位作者 Wei Huang Binbin Yan 《Defence Technology(防务技术)》 2025年第1期44-59,共16页
The multi-target assignment(MTA)problem,a crucial challenge in command control,mission planning,and a fundamental research focus in military operations,has garnered significant attention over the years.Extensively stu... The multi-target assignment(MTA)problem,a crucial challenge in command control,mission planning,and a fundamental research focus in military operations,has garnered significant attention over the years.Extensively studied across various domains such as land,sea,air,space,and electronics,the MTA problem has led to the emergence of numerous models and algorithms.To delve deeper into this field,this paper starts by conducting a bibliometric analysis on 463 Scopus database papers using CiteSpace software.The analysis includes examining keyword clustering,co-occurrence,and burst,with visual representations of the results.Following this,the paper provides an overview of current classification and modeling techniques for addressing the MTA problem,distinguishing between static multi-target assignment(SMTA)and dynamic multi-target assignment(DMTA).Subsequently,existing solution algorithms for the MTA problem are reviewed,generally falling into three categories:exact algorithms,heuristic algorithms,and machine learning algorithms.Finally,a development framework is proposed based on the"HIGH"model(high-speed,integrated,great,harmonious)to guide future research and intelligent weapon system development concerning the MTA problem.This framework emphasizes application scenarios,modeling mechanisms,solution algorithms,and system efficiency to offer a roadmap for future exploration in this area. 展开更多
关键词 Multi-target assignment Offensive and defensive confrontation Cooperative operation Modeling mechanism Solution algorithm CiteSpace analysis
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Mixed parking demand assignment in hub parking lots based on regression modeling
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作者 ZHANG Chu CHEN Kehan +1 位作者 CHEN Jun CHEN Jiayi 《Journal of Southeast University(English Edition)》 2025年第3期270-277,共8页
To adapt to the unique demand-supply features of accessory parking lots at passenger transport hubs,a mixed parking demand assignment method based on regression modeling is proposed.First,an optimal model aiming to mi... To adapt to the unique demand-supply features of accessory parking lots at passenger transport hubs,a mixed parking demand assignment method based on regression modeling is proposed.First,an optimal model aiming to minimize total time expenditure is constructed.It incorporates parking search time,walking time,and departure time,focusing on short-term parking features.Then,the information dimensions that the parking lot can obtain are evaluated,and three assignment strategies based on three types of regression models-linear regression(LR),extreme gradient boosting(XGBoost),and multilayer perceptron(MLP)-are proposed.A parking process simulation model is built using the traffic simulation package SUMO to facilitate data collection,model training,and case studies.Finally,the performance of the three strategies is com-pared,revealing that the XGBoost-based strategy performs the best in case parking lots,which reduces time expendi-ture by 29.3%and 37.2%,respectively,compared with the MLP-based strategy and LR-based strategy.This method offers diverse options for practical parking manage-ment. 展开更多
关键词 parking areas assignment hub parking lot regression-based modeling extreme gradient boosting(XG-Boost)
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Weapon-target assignment for unmanned aerial vehicles: A multi-strategy threshold public goods game approach
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作者 Wenhao Bi Zhaoxi Wang +1 位作者 Yang Xu An Zhang 《Defence Technology(防务技术)》 2025年第6期221-237,共17页
As a crucial process in the coordinated strikes of unmanned aerial vehicles(UAVs), weapon-target assignment is vital for optimizing the allocation of available weapons and effectively exploiting the capabilities of UA... As a crucial process in the coordinated strikes of unmanned aerial vehicles(UAVs), weapon-target assignment is vital for optimizing the allocation of available weapons and effectively exploiting the capabilities of UAVs. Existing weapon-target assignment methods primarily focus on macro cluster constraints while neglecting individual strategy updates. This paper proposes a novel weapon-target assignment method for UAVs based on the multi-strategy threshold public goods game(PGG). By analyzing the concept mapping between weapon-target assignment for UAVs and multi-strategy threshold PGG, a weapon-target assignment model for UAVs based on the multi-strategy threshold PGG is established, which is adaptively complemented by the diverse cooperation-defection strategy library and the utility function based on the threshold mechanism. Additionally, a multi-chain Markov is formulated to quantitatively describe the stochastic evolutionary dynamics, whose evolutionary stable distribution is theoretically derived through the development of a strategy update rule based on preference-based aspiration dynamic. Numerical simulation results validate the feasibility and effectiveness of the proposed method, and the impacts of selection intensity, preference degree and threshold on the evolutionary stable distribution are analyzed. Comparative simulations show that the proposed method outperforms GWO, DE, and NSGA-II, achieving 17.18% higher expected utility than NSGA-II and reducing evolutionary stable times by 25% in large-scale scenario. 展开更多
关键词 Unmanned aerial vehicles(UAVs) Weapon-target assignment Public goods game(PGG) Multi-chain markov Strategy update rule
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Enhanced interconnection and damping assignment passivity-based control for PM synchronous motors
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作者 Mohamed Azzi Lotfi Baghli +2 位作者 Ehsan Jamshidpour Phatiphat Thounthong Noureddine Takorabet 《Global Energy Interconnection》 2025年第4期657-667,共11页
Permanent Magnet Synchronous Motors(PMSMs)are widely employed in high-performance drive applications due to their superior efficiency and dynamic capabilities.However,their control remains challenging owing to nonline... Permanent Magnet Synchronous Motors(PMSMs)are widely employed in high-performance drive applications due to their superior efficiency and dynamic capabilities.However,their control remains challenging owing to nonlinear dynamics,parameter variations,and unmeasurable external disturbances,particularly load torquefluctuations.This study proposes an enhanced Interconnection and Damp-ing Assignment Passivity-Based Control(IDA-PBC)scheme,formulated within the port-controlled Hamiltonian(PCH)framework,to address these limitations.A nonlinear disturbance observer is embedded to estimate and compensate,in real time,for lumped mis-matched disturbances arising from parameter uncertainties and external loads.Additionally,aflatness-based control strategy is employed to generate the desired current references within the nonlinear drive system,ensuring accurate tracking of time-varying speed commands.This integrated approach preserves the system’s energy-based structure,enabling systematic stability analysis while enhancing robustness.The proposed control architecture also maintains low complexity with a limited number of tunable parameters,facilitating practical implementation.Simulation and experimental results under various operating conditions demonstrate the effectiveness and robustness of the proposed method.Comparative analysis with conventional proportional-integral(PI)control and standard IDA-PBC strategies confirms its capability to handle disturbances and maintain dynamic performance. 展开更多
关键词 Hamiltonian energy control Interconnection and damping assignment passivity-based control IDA-PBC Motor drives Permanent-magnet synchronous machine(PMSM) Speed control
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Traffic-aware static channel assignment algorithm in wireless mesh networks 被引量:1
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作者 陶军 柳津 +1 位作者 邵碧锐 刘智杰 《Journal of Southeast University(English Edition)》 EI CAS 2011年第4期370-374,共5页
A channel assignment algorithm with awareness of link traffic is proposed in multi-radio multi-channel wireless mesh networks. First, the physical interference model based on the signal-to-interference-plus-noise rati... A channel assignment algorithm with awareness of link traffic is proposed in multi-radio multi-channel wireless mesh networks. First, the physical interference model based on the signal-to-interference-plus-noise ratio and successful transmission condition is described. The model is more suitable for a wireless communication environment than other existing models. Secondly, a pure integer quadratic programming (PIQP) model is used to solve the channel assignment problem and improve the capacity of wireless mesh networks. Consequently, a traffic- aware static channel assignment algorithm(TASC) is designed. The algorithm adopts some network parameters, including the network connectivity, the limitation of the number of radios and the successful transmission conditions in wireless communications. The TASC algorithm can diminish network interference and increase the efficiency of channel assignment while keeping the connectivity of the network. Finally, the feasibility and effectivity of the channel assignment solution are illustrated by the simulation results. Compared witb similar algorithms, the proposed algorithm can increase the capacity of WMNs. 展开更多
关键词 multi-radio multi-channel wireless mesh network static channel assignment traffic-aware
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18Cr2Ni4WA钢渗碳后的环保型热处理 被引量:2
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作者 王新宇 杨立新 +3 位作者 刘艳梅 刘刚 康冲 颜廷宇 《金属热处理》 CAS CSCD 北大核心 2024年第11期272-277,共6页
针对现有浴炉复合等温淬火工艺的高污染、高能耗问题,提出了真空淬火、分级淬火、气氛炉复合等温淬火3种替代工艺,对比分析了18Cr2Ni4WA钢渗碳后,经3种工艺淬火+深冷+回火处理后的渗碳层和心部的显微组织、硬度和力学性能。结果表明,3... 针对现有浴炉复合等温淬火工艺的高污染、高能耗问题,提出了真空淬火、分级淬火、气氛炉复合等温淬火3种替代工艺,对比分析了18Cr2Ni4WA钢渗碳后,经3种工艺淬火+深冷+回火处理后的渗碳层和心部的显微组织、硬度和力学性能。结果表明,3种淬火方案处理18Cr2Ni4WA钢的渗碳层组织均以回火马氏体为主,但心部组织不同。真空淬火和分级淬火工艺下,心部组织为回火马氏体,复合等温淬火工艺下的心部组织为回火索氏体,因此真空淬火和分级淬火下硬度、抗拉强度更高,而复合等温淬火工艺下塑韧性更好。3种替代工艺处理18Cr2Ni4WA钢的各性能指标均能满足应用指标要求,且均未使用高污染高能耗的碱槽设备,可实现渗碳后绿色热处理的目标。 展开更多
关键词 18CR2NI4wa 显微组织 复合等温淬火 真空淬火 分级淬火 力学性能
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Dynamic Weapon Target Assignment Based on Intuitionistic Fuzzy Entropy of Discrete Particle Swarm 被引量:18
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作者 Yi Wang Jin Li +1 位作者 Wenlong Huang Tong Wen 《China Communications》 SCIE CSCD 2017年第1期169-179,共11页
Aiming at the problems of convergence-slow and convergence-free of Discrete Particle Swarm Optimization Algorithm(DPSO) in solving large scale or complicated discrete problem, this article proposes Intuitionistic Fuzz... Aiming at the problems of convergence-slow and convergence-free of Discrete Particle Swarm Optimization Algorithm(DPSO) in solving large scale or complicated discrete problem, this article proposes Intuitionistic Fuzzy Entropy of Discrete Particle Swarm Optimization(IFDPSO) and makes it applied to Dynamic Weapon Target Assignment(WTA). First, the strategy of choosing intuitionistic fuzzy parameters of particle swarm is defined, making intuitionistic fuzzy entropy as a basic parameter for measure and velocity mutation. Second, through analyzing the defects of DPSO, an adjusting parameter for balancing two cognition, velocity mutation mechanism and position mutation strategy are designed, and then two sets of improved and derivative algorithms for IFDPSO are put forward, which ensures the IFDPSO possibly search as much as possible sub-optimal positions and its neighborhood and the algorithm ability of searching global optimal value in solving large scale 0-1 knapsack problem is intensified. Third, focusing on the problem of WTA, some parameters including dynamic parameter for shifting firepower and constraints are designed to solve the problems of weapon target assignment. In addition, WTA Optimization Model with time and resource constraints is finally set up, which also intensifies the algorithm ability of searching global and local best value in the solution of WTA problem. Finally, the superiority of IFDPSO is proved by several simulation experiments. Particularly, IFDPSO, IFDPSO1~IFDPSO3 are respectively effective in solving large scale, medium scale or strict constraint problems such as 0-1 knapsack problem and WTA problem. 展开更多
关键词 intuitionistic fuzzy entropy discrete particle swarm optimization algorithm 0-1 knapsack problem weapon target assignment
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Storage Assignment Optimization in a Multi-tier Shuttle Warehousing System 被引量:10
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作者 WANG Yanyan MOU Shandong WU Yaohua 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第2期421-429,共9页
The current mathematical models for the storage assignment problem are generally established based on the traveling salesman problem(TSP),which has been widely applied in the conventional automated storage and retri... The current mathematical models for the storage assignment problem are generally established based on the traveling salesman problem(TSP),which has been widely applied in the conventional automated storage and retrieval system(AS/RS).However,the previous mathematical models in conventional AS/RS do not match multi-tier shuttle warehousing systems(MSWS) because the characteristics of parallel retrieval in multiple tiers and progressive vertical movement destroy the foundation of TSP.In this study,a two-stage open queuing network model in which shuttles and a lift are regarded as servers at different stages is proposed to analyze system performance in the terms of shuttle waiting period(SWP) and lift idle period(LIP) during transaction cycle time.A mean arrival time difference matrix for pairwise stock keeping units(SKUs) is presented to determine the mean waiting time and queue length to optimize the storage assignment problem on the basis of SKU correlation.The decomposition method is applied to analyze the interactions among outbound task time,SWP,and LIP.The ant colony clustering algorithm is designed to determine storage partitions using clustering items.In addition,goods are assigned for storage according to the rearranging permutation and the combination of storage partitions in a 2D plane.This combination is derived based on the analysis results of the queuing network model and on three basic principles.The storage assignment method and its entire optimization algorithm method as applied in a MSWS are verified through a practical engineering project conducted in the tobacco industry.The applying results show that the total SWP and LIP can be reduced effectively to improve the utilization rates of all devices and to increase the throughput of the distribution center. 展开更多
关键词 Multi-tier shuttle warehousing system storage assignment optimization open queuing network ant colony clustering algorithm
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WiFi over Fiber Link and Wavelength Assignment Protocol for Internet of Things 被引量:2
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作者 徐坤 庞文凤 +5 位作者 孙小强 沈希 刘盈 梅仲豪 孟学军 林金桐 《China Communications》 SCIE CSCD 2011年第1期119-125,共7页
A novel Wireless Fidelity (WiFi) over fiber link and a wavelength assignment protocol are proposed to provide sufficient bandwidth and extensive coverage range for the various applications in the Internet of Things (I... A novel Wireless Fidelity (WiFi) over fiber link and a wavelength assignment protocol are proposed to provide sufficient bandwidth and extensive coverage range for the various applications in the Internet of Things (IoT).The performance of the WiFi over fiber-based wireless IoT network is evaluated in terms of error vector magnitude (EVM) and data throughput for both the up and down links between the WiFi central control system and remote radio units (RRUs).The experimental results illustrate the reliability of the fiber transmission of 64 Quadrature Amplitude Modulation (64QAM) WiFi signals by direct analog modulation.In order to efficiently utilize the wavelength resources,we also demonstrated the wavelength assignment protocol by employing optical switching configurations in Central Station (CS) to realize the wavelength switching,and the simulation results indicate the queuing size and the corresponding queue delay for different numbers of available wavelengths. 展开更多
关键词 wireless fidelity radio over fiber wavelength assignment Internet of Things
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Dependent task assignment algorithm based on particle swarm optimization and simulated annealing in ad-hoc mobile cloud 被引量:3
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作者 Huang Bonan Xia Weiwei +4 位作者 Zhang Yueyue Zhang Jing Zou Qian Yan Feng Shen Lianfeng 《Journal of Southeast University(English Edition)》 EI CAS 2018年第4期430-438,共9页
In order to solve the problem of efficiently assigning tasks in an ad-hoc mobile cloud( AMC),a task assignment algorithm based on the heuristic algorithm is proposed. The proposed task assignment algorithm based on pa... In order to solve the problem of efficiently assigning tasks in an ad-hoc mobile cloud( AMC),a task assignment algorithm based on the heuristic algorithm is proposed. The proposed task assignment algorithm based on particle swarm optimization and simulated annealing( PSO-SA) transforms the dependencies between tasks into a directed acyclic graph( DAG) model. The number in each node represents the computation workload of each task and the number on each edge represents the workload produced by the transmission. In order to simulate the environment of task assignment in AMC,mathematical models are developed to describe the dependencies between tasks and the costs of each task are defined. PSO-SA is used to make the decision for task assignment and for minimizing the cost of all devices,which includes the energy consumption and time delay of all devices.PSO-SA also takes the advantage of both particle swarm optimization and simulated annealing by selecting an optimal solution with a certain probability to avoid falling into local optimal solution and to guarantee the convergence speed. The simulation results show that compared with other existing algorithms,the PSO-SA has a smaller cost and the result of PSO-SA can be very close to the optimal solution. 展开更多
关键词 ad-hoc mobile cloud task assignment algorithm directed acyclic graph particle swarm optimization simulated annealing
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An Ant Colony Algorithm Based on Cross-Layer Design for Routing and Wavelength Assignment in Optical Satellite Networks 被引量:17
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作者 Guoli Wen Qi Zhang +2 位作者 Houtian Wang Qinghua Tian Ying Tao 《China Communications》 SCIE CSCD 2017年第8期63-75,共13页
This paper introduces an ant colony routing and wavelength assignment algorithm based on cross-layer design(CL-ACRWA),which can overcome the adverse effects of Doppler wavelength shift on data transmission in optical ... This paper introduces an ant colony routing and wavelength assignment algorithm based on cross-layer design(CL-ACRWA),which can overcome the adverse effects of Doppler wavelength shift on data transmission in optical satellite networks. Firstly, a cross-layer optimization model is built, which considers the Doppler wavelength shift, the transmission delay as well as wavelength-continuity constraint. Then an ant colony algorithm is utilized to solve the cross-layer optimization model, resulting in finding an optimal light path satisfying the above constraints for every connection request. The performance of CL-ACRWA is measured by the communication success probability, the convergence property and the transmission delay. Simulation results show that CL-ACRWA performs well in communication success probability and has good global search ability as well as fast convergence speed. Meanwhile, the transmission delay can meet the basic requirement of real-time transmission of business. 展开更多
关键词 optical satellite network routing and wavelength assignment ant colony optimization cross-layer design Doppler wavelength shift
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Task Assignment Problem of Robots in a Smart Warehouse Environment 被引量:1
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作者 Zhenping Li Wenyu Li Lulu Jiang 《Management Studies》 2016年第4期167-175,共9页
The task assignment problem of robots in a smart warehouse environment (TARSWE) based on cargo-to-person is investigated. Firstly, the sites of warehouse robots and the order picking tasks are given and the task ass... The task assignment problem of robots in a smart warehouse environment (TARSWE) based on cargo-to-person is investigated. Firstly, the sites of warehouse robots and the order picking tasks are given and the task assignment problem for picking one order is formulated into a mathematical model to minimize the total operation cost. Then a heuristic algorithm is designed to solve the task assignment problem for picking multiple orders. Finally, simulations are done by using the orders data of online bookstore A. The results show that using the heuristic algorithm of this paper to assign robots, the cost was reduced by 2% and it can effectively avoid far route and unbalanced workload of robots. The feasibility and validity of the model and algorithm are verified. The model and algorithm in this paper provide a theoretical basis to solve the TARSWE. 展开更多
关键词 smart warehouse ROBOTS cargo-to-person task assignment mathematical model heuristic algorithm
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