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Distributed dynamic task allocation for unmanned aerial vehicle swarm systems:A networked evolutionary game-theoretic approach

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Chinese Journal of Aeronautics 2024年第6期37卷 182-204页

作者： zhe zhang Ju JIANG Haiyan XU Wen-An zhang College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China College of Economics and Management Nanjing University of Aeronautics and AstronauticsNanjing 211106China College of Information Engineering Zhejiang University of TechnologyHangzhou 310023China

Task allocation is a key aspect of Unmanned Aerial Vehicle(UAV)swarm collaborative *** an continuous increase of UAVs’scale and the complexity and uncertainty of tasks,existing methods have poor performance in computing efficiency,robustness,and realtime allocation,and there is a lack of theoretical analysis on the convergence and optimality of the *** paper presents a novel intelligent framework for distributed decision-making based on the evolutionary game theory to address task allocation for a UAV swarm system in uncertain scenarios.A task allocation model is designed with the local utility of an individual and the global utility of the ***,the paper analytically derives a potential function in the networked evolutionary potential game and proves that the optimal solution of the task allocation problem is a pure strategy Nash equilibrium of a finite strategy ***,a PayOff-based Time-Variant Log-linear Learning Algorithm(POTVLLA)is proposed,which includes a novel learning strategy based on payoffs for an individual and a time-dependent Boltzmann *** former aims to reduce the system’s computational burden and enhance the individual’s effectiveness,while the latter can ensure that the POTVLLA converges to the optimal Nash equilibrium with a probability of *** simulation results show that the approach is optimal,robust,scalable,and fast adaptable to environmental changes,even in some realistic situations where some UAVs or tasks are likely to be lost and increased,further validating the effectiveness and superiority of the proposed framework and algorithm.

关键词： Task allocation Unmanned Aerial Vehicles(UAV) Game theory Log-linear learning Distributed optimization algorithm

Approach to conceptual data integration for multidimensional data analysis in e-commerce

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Journal of Systems Engineering and Electronics 2006年第3期17卷 635-641页

作者： zhang zhe Huang Pei School of Management Fudan Univ. Shanghai 200433P. R. China School of Management Shanghai Jiaotong Univ. Shanghai 200052 P. R. China

In e-commerce the multidimensional data analysis based on the Web data needs integrating various data sources such as XML data and relational data on the conceptual level. A conceptual data description approach to multidimensional data model the UML galaxy diagram is presented in order to conduct multidimensional data analysis for multiple subjects. The approach is illuminated using a case of 2_roots UML galaxy diagram that takes marketing analysis of TV products involved one retailer and several suppliers into consideration.

关键词： conceptual data integration multidimensional data analysis e-commerce

Characteristic of Fresh and Harden Properties of Polyvinyl Alcohol Fibre Reinforced Alkali Activated Composite

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Journal of Renewable Materials 2023年第3期11卷 1321-1337页

作者： Yiguang Wang zhe zhang Xun zhang School of Civil Engineering Zhengzhou UniversityZhengzhou450001China Henan Provincial Communications Planning Survey&Design Institute Co.Ltd.Zhengzhou450001China

Fibre can enhance the mechanical properties of cement-based composites,but fibre also degrades their ***,the quantitative effects of fiber content and length-diameter ratio on alkali-activated materials are still *** aspect ratio,volume fraction of polyvinyl alcohol fibre(PVAF),and various water-binder ratio were employed to prepare a total of 26 groups of fibre reinforced alkali-activated composite(FRAAC).The influence of PVAF fibre factor(product of fiber volume fraction and length-diameter ratio)on flowability,compactness,strength,and crack fractal dimension of FRAAC was *** influence of water-binder ratio on the plastic viscosity of FRAAC was more significant than that on the yield *** fibre factor was lower than critical value of 150,the influence of fibres could be *** reason was that the space between fibres was distant,so the flowability of FRAAC was not impacted by *** this time,fibres were challenging to restrict the cracks in matrix and increase their mechanical *** fibre factor was higher than critical value 150 and lower than density packing value 450,the flexural strength,compressive strength and crack fractal dimension of FRAAC were considerably enhanced,and the FRAAC could still flow easily under dead *** fibre factor were above 450,noteworthy fibre balling considerably decreased the flowability,leading to poor solidity and reduced compressive ***,the ideal content of PVAF in alkali activated composite is between 150/(l/d)and 450/(l/d).

关键词： Alkali-activated composite fibre reinforced composite fibre factor flowability strength fractal dimension

Modified constriction particle swarm optimization algorithm

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Journal of Systems Engineering and Electronics 2015年第5期26卷 1107-1113页

作者： zhe zhang Limin Jia Yong Qin Traffic and Transportation School Beijing Jiaotong University State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing Research Center of Urban Traffic Information Sensing and Service Technologies Beijing Jiaotong University

To deal with the demerits of constriction particle swarm optimization(CPSO), such as relapsing into local optima, slow convergence velocity, a modified CPSO algorithm is proposed by improving the velocity update formula of CPSO. The random velocity operator from local optima to global optima is added into the velocity update formula of CPSO to accelerate the convergence speed of the particles to the global optima and reduce the likelihood of being trapped into local optima. Finally the convergence of the algorithm is verified by calculation examples.

关键词： particle swarm optimization random speed operator convergence global optima

Torsional Fatigue Cracking and Fracture Behaviors of Cold-Drawn Copper:Effects of Microstructure and Axial Stress

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Acta Metallurgica Sinica(English Letters) 2019年第12期32卷 1521-1529页

作者： Rong-Hua Li Peng zhang zhe-Feng zhang School of Mechanical Engineering Liaoning Shihua UniversityFushun 113001China Laboratory of Fatigue and Fracture for Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

The fatigue cracking and fracture behavior of cold-drawn copper subjected to cyclic torsional loading were investigated in this *** was found that with increasing stress amplitude,the fracture mode of cold-drawn copper gradually changes from a shear fracture on transverse maximum shear stress plane to a mixed shear mode on both transverse and longitudinal shear planes and finally turns to the shear fracture on multiple longitudinal shear *** the cracking morphology and the relationship between torsional fatigue cracking and the grain boundaries,the fracture mechanism of cold-drawn copper under cyclic torsional loading was analyzed and proposed by considering the effects of the microstructure and axial stress caused by *** of the promotion of the grain boundary distribution on longitudinal crack propagation and the inhibition of axial stress on transverse crack grown,the tendency of crack propagation along the longitudinal direction increases with increasing stress levels.

关键词： Torsion Fatigue behavior Crack propagation Fracture mechanisms Axial stress Copper

Corrosion Prevention and Surface Protection for Automobile Design

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稀有金属材料与工程 2012年第S1期41卷 140-143页

作者： zhe, zhang Ting, Wang Chinese FAW R&D Ctr Changchun 130011 Peoples R China QiMing Informat Technol Co Ltd Changchun 130011 Peoples R China

With the rapid progress of our national automobile industry,higher and higher petitions of the automobile corrosion prevention property were *** prevention and surface protection technology have become a hot topic in recent *** first paragraph of this paper describe the automobile parts which could be easily corroded,and then analyze the reasons for *** second paragraph describe the necessary measures of how to improve the automobile corrosion prevention *** rules of choosing metal materials for automobile design have also been given.

关键词： automobile design corrosion prevention surface protection corrosion resistance

Lesions in Porcine Liver Tissues Created by Continuous High Intensity Ultrasound Exposures in Vitro

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Chinese Physics Letters 2013年第2期30卷 151-154页

作者： zhang zhe CHEN Tao zhang Dong Key Laboratory of Modern Acoustics(Ministry of Education) Nanjing UniversityNanjing 210093

Lesions in porcine liver tissues created by continuous high intensity focused ultrasound(HIFU)exposures in vitro are theoretically and experimentally investigated,with the transmitter moving along a linear path at a fixed *** simulations of the lesion formation are performed based on the Khokhlov-Zabolotskaya-Kuznetov equation and the bio-heat *** order to verify the theoretical predictions,experiments are performed in the one-dimensional scanning mode to measure the cross-sectional area of lesions created in the in vitro porcine liver exposed to 1.01-MHz HIFU pulses with the acoustic power of 70 *** results indicate that,compared to the traditional discrete treatment protocol,the application of a continuous scanning model can create more uniform lesions in tissues and significantly reduces the total treatment time from 47 s to 30 s.

关键词： Lesions Liver Ultrasound

BiCoO3-doped （Ko.47sN ***）（N bo.8Tao.2）03 lead-free piezoelectric ceramics

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Frontiers of Materials Science 2012年第4期6卷 311-318页

作者： Ke-Pi CHEN zhe zhang School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing 102206China

（1-x）（***）（***0.2）O3-xBiCoO3 （KNLNT-BC） lead-free piezoelectric ceramics were prepared by the conventional solid-state sintering method. Effects of the BC content on the phase structure, microstructure and electrical properties of KNLNT-BC ceramics were investigated. XRD patterns reveal that all the ceramic samples are in the pure perovskite-type structure, and the phase structure changes from the tetragonal to pseudo-cubic phase with the increase of the BC content. After the substitution of BC, the grain size is significantly reduced and relaxer behaviors are induced. By adding a small amount of BC to KNLNT ceramics, piezoelectric properties are improved, while further addition of BC makes the piezoelectric properties deteriorate markedly. The optimized electrical properties atx= 0.005 are as follows： d33 = 194 pC/N, kp = 0.44.

关键词： lead-free ceramic potassium sodium niobate BiCo03 piezoelectric property

Optimal Design of Two Road Networks Based on their Properties

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Acta Mathematicae Applicatae Sinica 2007年第2期23卷 337-352页

作者： Ming-zhe Li Yan zhang Faculty of Economics Fukuoka University 8-19-1 Nanakuma Jonan-ku Fukuoka 814-0180 Japan

In this paper, we discuss some fundamental properties of two idealized typical networks, namely, grid type and radial-circular type. The discussion is based on SPCP （Shortest Path Counting Problem）, which reflects the traffic density of a road segment. Furthermore, we compare their effectiveness based on the obtained results of the above two road networks, and suggest some proposals on the design of car lanes by considering the direction of a road segment in relation to these road networks.

关键词： SPCP DSPCP grid radial-circular optimal design of road networks