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NEURAL NETWORK PREDICTIVE CONTROL WITH HIERARCHICAL GENETIC ALGORITHM
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作者 刘宝坤 王慧 李光泉 《Transactions of Tianjin University》 EI CAS 1998年第2期48-50,共3页
A kind of predictive control based on the neural network(NN) for nonlinear systems with time delay is addressed.The off line NN model is obtained by using hierarchical genetic algorithms (HGA) to train a sequence da... A kind of predictive control based on the neural network(NN) for nonlinear systems with time delay is addressed.The off line NN model is obtained by using hierarchical genetic algorithms (HGA) to train a sequence data of input and output.Output predictions are obtained by recursively mapping the NN model.The error rectification term is introduced into a performance function that is directly optimized while on line control so that it overcomes influences of the mismatched model and disturbances,etc.Simulations show the system has good dynamic responses and robustness. 展开更多
关键词 neural networks(NN) predictive control hierarchical genetic algorithms nonlinear system
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AN OPTIMUM VEHICULAR PATH ALGORITHM FOR TRAFFIC NETWORK BASED ON HIERARCHICAL SPATIAL REASONING 被引量:4
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作者 Lu Feng Zhou Chenghu Wan Qing 《Geo-Spatial Information Science》 2000年第4期36-42,共7页
Human beings’ intellection is the characteristic of a distinct hierarchy and can be taken to construct a heuristic in the shortest path algorithms.It is detailed in this paper how to utilize the hierarchical reasonin... Human beings’ intellection is the characteristic of a distinct hierarchy and can be taken to construct a heuristic in the shortest path algorithms.It is detailed in this paper how to utilize the hierarchical reasoning on the basis of greedy and directional strategy to establish a spatial heuristic,so as to improve running efficiency and suitability of shortest path algorithm for traffic network.The authors divide urban traffic network into three hierarchies and set forward a new node hierarchy division rule to avoid the unreliable solution of shortest path.It is argued that the shortest path,no matter distance shortest or time shortest,is usually not the favorite of drivers in practice.Some factors difficult to expect or quantify influence the drivers’ choice greatly.It makes the drivers prefer choosing a less shortest,but more reliable or flexible path to travel on.The presented optimum path algorithm,in addition to the improvement of the running efficiency of shortest path algorithms up to several times,reduces the emergence of those factors,conforms to the intellection characteristic of human beings,and is more easily accepted by drivers.Moreover,it does not require the completeness of networks in the lowest hierarchy and the applicability and fault tolerance of the algorithm have improved.The experiment result shows the advantages of the presented algorithm.The authors argued that the algorithm has great potential application for navigation systems of large_scale traffic networks. 展开更多
关键词 OPTIMUM PATH algorithm TRAFFIC NETWORK hierarchical spatial REASONING
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Edge Crossing Minimization Algorithm for Hierarchical Graphs Based on Genetic Algorithms 被引量:2
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作者 Shen Wei xiang, Huang Jing wei College of Computer, Wuhan University, Wuhan 430072, China 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期555-559,共5页
We present an edge crossing minimization algorithm for hierarchical graphs based on genetic algorithms, and comparing it with some heuristic algorithms. The proposed algorithm is more efficient and has the following a... We present an edge crossing minimization algorithm for hierarchical graphs based on genetic algorithms, and comparing it with some heuristic algorithms. The proposed algorithm is more efficient and has the following advantages: the frame of the algorithms is unified, the method is simple, and its implementation and revision are easy. 展开更多
关键词 hierarchical graph edge crossing genetic algorithms
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A Novel Handoff Algorithm for Hierarchical Cellular Networks 被引量:2
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作者 Xiaorong Zhu Mengrong Li +1 位作者 Wenchao Xia Hongbo Zhu 《China Communications》 SCIE CSCD 2016年第8期136-147,共12页
In this paper, we propose a novel speed and service-sensitive handoff algorithm and analytical model for hierarchical cellular networks.First, we use the Gauss-Markov mobility model to predict the speeds of mobile sta... In this paper, we propose a novel speed and service-sensitive handoff algorithm and analytical model for hierarchical cellular networks.First, we use the Gauss-Markov mobility model to predict the speeds of mobile stations, and divide mobile stations into three classes based on the predicted speeds: fast, medium-speed, and slow.Then, according to the mobility classification,network conditions, and service types, mobile stations will be handoff to the proper target networks prior to the deterioration of the currently operating channel. We further develop an analytical model to evaluate the performance of such a hierarchical system with different speed classes and service types. Simulations and analytical results show that the proposed handoff algorithm can significantly improve the network performance in terms of the handoff failure probability, unnecessary handoff probability, and network throughput, comparing with the traditional algorithms. 展开更多
关键词 hierarchical cellular networks handoff algorithm Gauss-Markov mobility model analytical model
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Discrete logistics network design model under interval hierarchical OD demand based on interval genetic algorithm 被引量:2
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作者 李利华 符卓 +1 位作者 周和平 胡正东 《Journal of Central South University》 SCIE EI CAS 2013年第9期2625-2634,共10页
Aimed at the uncertain characteristics of discrete logistics network design,an interval hierarchical triangular uncertain OD demand model based on interval demand and network flow is presented.Under consideration of t... Aimed at the uncertain characteristics of discrete logistics network design,an interval hierarchical triangular uncertain OD demand model based on interval demand and network flow is presented.Under consideration of the system profit,the uncertain demand of logistics network is measured by interval variables and interval parameters,and an interval planning model of discrete logistics network is established.The risk coefficient and maximum constrained deviation are defined to realize the certain transformation of the model.By integrating interval algorithm and genetic algorithm,an interval hierarchical optimal genetic algorithm is proposed to solve the model.It is shown by a tested example that in the same scenario condition an interval solution[3275.3,3 603.7]can be obtained by the model and algorithm which is obviously better than the single precise optimal solution by stochastic or fuzzy algorithm,so it can be reflected that the model and algorithm have more stronger operability and the solution result has superiority to scenario decision. 展开更多
关键词 uncertainty interval planning hierarchical OD logistics network design genetic algorithm
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An improved non-dominated sorting biogeography-based optimization algorithm for multi-objective land-use allocation:a case study in Kigali-Rwanda 被引量:1
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作者 Olive Niyomubyeyi Mozafar Veysipanah +2 位作者 Sam Sarwat Petter Pilesjö Ali Mansourian 《Geo-Spatial Information Science》 CSCD 2024年第4期968-982,共15页
With the continuous increase of rapid urbanization and population growth,sustainable urban land-use planning is becoming a more complex and challenging task for urban planners and decision-makers.Multi-objective land-... With the continuous increase of rapid urbanization and population growth,sustainable urban land-use planning is becoming a more complex and challenging task for urban planners and decision-makers.Multi-objective land-use allocation can be regarded as a complex spatial optimization problem that aims to achieve the possible trade-offs among multiple and conflicting objectives.This paper proposes an improved Non-dominated Sorting Biogeography-Based Optimization(NSBBO)algorithm for solving the multi-objective land-use allocation problem,in which maximum accessibility,maximum compactness,and maximum spatial integration were formulated as spatial objectives;and space syntax analysis was used to analyze the potential movement patterns in the new urban planning area of the city of Kigali,Rwanda.Efficient Non-dominated Sorting(ENS)algorithm and crossover operator were integrated into classical NSBBO to improve the quality of non-dominated solutions,and local search ability,and to accelerate the convergence speed of the algorithm.The results showed that the proposed NSBBO exhibited good optimal solutions with a high hypervolume index compared to the classical NSBBO.Furthermore,the proposed algorithm could generate optimal land use scenarios according to the preferred objectives,thus having the potential to support the decision-making of urban planners and stockholders in revising and updating the existing detailed master plan of land use. 展开更多
关键词 Multi-objective land-use allocation spatial optimization sustainable urban planning Non-dominated Sorting biogeography-based Optimization(NSBBO)algorithm
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A HIERARCHICAL IDENTIFICATION ALGORITHM FOR THE EXTENDED EXPONENTIAL MODEL
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作者 何建敏 达庆利 《Journal of Southeast University(English Edition)》 EI CAS 1991年第1期77-84,共8页
A new hierarchical identification algorithm is proposed for solving the identi-fication problem of the extended exponential model,which is used frequently in ecological,social and economical systems.By using the zero ... A new hierarchical identification algorithm is proposed for solving the identi-fication problem of the extended exponential model,which is used frequently in ecological,social and economical systems.By using the zero character of the optimal Lagrangianmultipliers of the equivalent identification problem,a two-level structure of the algorithmis derived first.Then,the convergence and the correspondence with the conventionalnonlinear approaches of the algorithm are proved.The results of simulation and applica-tion show that its convergent rate is greatly higher than that of the L-Mmethod. 展开更多
关键词 least-square METHODS IDENTIFICATION optimization/hierarchical algorithm SOCIAL and economical systems
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Hybrid quantum–classical multi-agent decision-making framework based on hierarchical Bayesian networks in the noisy intermediate-scale quantum era
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作者 Hao Shi Chenghao Han +1 位作者 Peng Wang Ming Zhang 《Chinese Physics B》 2025年第12期61-74,共14页
Although quantum Bayesian networks provide a promising paradigm for multi-agent decision-making,their practical application faces two challenges in the noisy intermediate-scale quantum(NISQ)era.Limited qubit resources... Although quantum Bayesian networks provide a promising paradigm for multi-agent decision-making,their practical application faces two challenges in the noisy intermediate-scale quantum(NISQ)era.Limited qubit resources restrict direct application to large-scale inference tasks.Additionally,no quantum methods are currently available for multi-agent collaborative decision-making.To address these,we propose a hybrid quantum–classical multi-agent decision-making framework based on hierarchical Bayesian networks,comprising two novel methods.The first one is a hybrid quantum–classical inference method based on hierarchical Bayesian networks.It decomposes large-scale hierarchical Bayesian networks into modular subnetworks.The inference for each subnetwork can be performed on NISQ devices,and the intermediate results are converted into classical messages for cross-layer transmission.The second one is a multi-agent decision-making method using the variational quantum eigensolver(VQE)in the influence diagram.This method models the collaborative decision-making with the influence diagram and encodes the expected utility of diverse actions into a Hamiltonian and subsequently determines the intra-group optimal action efficiently.Experimental validation on the IonQ quantum simulator demonstrates that the hierarchical method outperforms the non-hierarchical method at the functional inference level,and the VQE method can obtain the optimal strategy exactly at the collaborative decision-making level.Our research not only extends the application of quantum computing to multi-agent decision-making but also provides a practical solution for the NISQ era. 展开更多
关键词 quantum Bayesian networks multi-agent decision-making hybrid quantum–classical algorithms hierarchical Bayesian networks
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A NOVEL CLASSIFICATION METHOD FOR TROPICAL CYCLONE INTENSITY CHANGE ANALYSIS BASED ON HIERARCHICAL PARTICLE SWARM OPTIMIZATION ALGORITHM
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作者 耿焕同 孙家清 +1 位作者 张伟 吴正雪 《Journal of Tropical Meteorology》 SCIE 2017年第1期113-120,共8页
Based on the tropical cyclone(TC) observations in the western North Pacific from 2000 to 2008, this paper adopts the particle swarm optimization(PSO) algorithm of evolutionary computation to optimize one comprehensive... Based on the tropical cyclone(TC) observations in the western North Pacific from 2000 to 2008, this paper adopts the particle swarm optimization(PSO) algorithm of evolutionary computation to optimize one comprehensive classification rule, and apply the optimized classification rule to the forecasting of TC intensity change. In the process of the optimization, the strategy of hierarchical pruning has been adopted in the PSO algorithm to narrow the search area,and thus to enhance the local search ability, i.e. hierarchical PSO algorithm. The TC intensity classification rule involves core attributes including 12-HMWS, MPI, and Rainrate which play vital roles in TC intensity change. The testing accuracy using the new mined rule by hierarchical PSO algorithm reaches 89.6%. The current study shows that the novel classification method for TC intensity change analysis based on hierarchic PSO algorithm is not only easy to explain the source of rule core attributes, but also has great potential to improve the forecasting of TC intensity change. 展开更多
关键词 tropical cyclone intensity hierarchical PSO algorithm classification and forecasting C4 5 algorithm
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Hierarchical Evolutionary Algorithms and Its Application in Transonic Airfoil Optimization in Aerodynamics
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作者 王江峰 伍贻兆 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2003年第1期1-6,共6页
Hierarchical evolutionary algorithms based on genetic algorithms (GAs) and Nash strategy of game theory are proposed to accelerate the optimization process and implemented in transonic aerodynamic shape optimization p... Hierarchical evolutionary algorithms based on genetic algorithms (GAs) and Nash strategy of game theory are proposed to accelerate the optimization process and implemented in transonic aerodynamic shape optimization problems Inspired from the natural evolution history that different periods with certain environments have different criteria for the evaluations of individuals’ fitness, a hierarchical fidelity model is introduced to reach high optimization efficiency The shape of an NACA0012 based airfoil is optimized in maximizing the lift coefficient under a given transonic flow condition Optimized results are presented and compared with the single model results and traditional GA 展开更多
关键词 transonic flow aerodynamic optimization finite element method unstructured grid hierarchical fidelity models evolutionary algorithms
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Hybrid Hierarchical Particle Swarm Optimization with Evolutionary Artificial Bee Colony Algorithm for Task Scheduling in Cloud Computing
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作者 Shasha Zhao Huanwen Yan +3 位作者 Qifeng Lin Xiangnan Feng He Chen Dengyin Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第1期1135-1156,共22页
Task scheduling plays a key role in effectively managing and allocating computing resources to meet various computing tasks in a cloud computing environment.Short execution time and low load imbalance may be the chall... Task scheduling plays a key role in effectively managing and allocating computing resources to meet various computing tasks in a cloud computing environment.Short execution time and low load imbalance may be the challenges for some algorithms in resource scheduling scenarios.In this work,the Hierarchical Particle Swarm Optimization-Evolutionary Artificial Bee Colony Algorithm(HPSO-EABC)has been proposed,which hybrids our presented Evolutionary Artificial Bee Colony(EABC),and Hierarchical Particle Swarm Optimization(HPSO)algorithm.The HPSO-EABC algorithm incorporates both the advantages of the HPSO and the EABC algorithm.Comprehensive testing including evaluations of algorithm convergence speed,resource execution time,load balancing,and operational costs has been done.The results indicate that the EABC algorithm exhibits greater parallelism compared to the Artificial Bee Colony algorithm.Compared with the Particle Swarm Optimization algorithm,the HPSO algorithmnot only improves the global search capability but also effectively mitigates getting stuck in local optima.As a result,the hybrid HPSO-EABC algorithm demonstrates significant improvements in terms of stability and convergence speed.Moreover,it exhibits enhanced resource scheduling performance in both homogeneous and heterogeneous environments,effectively reducing execution time and cost,which also is verified by the ablation experimental. 展开更多
关键词 Cloud computing distributed processing evolutionary artificial bee colony algorithm hierarchical particle swarm optimization load balancing
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Mathematical Modeling Algorithms for Creating New Materials with Desired Properties Using Nano-Hierarchical Structures
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作者 Olga Hachay Andrey Khachay Oleg Khachay 《Advances in Materials Physics and Chemistry》 2019年第11期211-217,共7页
In the enormous and still poorly mastered gap between the macro level, where well developed continuum theories of continuous media and engineering methods of calculation and design operate, and atomic, subordinate to ... In the enormous and still poorly mastered gap between the macro level, where well developed continuum theories of continuous media and engineering methods of calculation and design operate, and atomic, subordinate to the laws of quantum mechanics, there is an extensive meso-hierarchical level of the structure of matter. At this level unprecedented previously products and technologies can be artificially created. Nano technology is a qualitatively new strategy in technology: it creates objects in exactly the opposite way—large objects are created from small ones [1]. We have developed a new method for modeling acoustic monitoring of a layered-block elastic medium with several inclusions of various physical and mechanical hierarchical structures [2]. An iterative process is developed for solving the direct problem for the case of three hierarchical inclusions of l, m, s-th ranks based on the use of 2D integro-differential equations. The degree of hierarchy of inclusions is determined by the values of their ranks, which may be different, while the first rank is associated with the atomic structure, the following ranks are associated with increasing geometric sizes, which contain inclusions of lower ranks and sizes. Hierarchical inclusions are located in different layers one above the other: the upper one is abnormally plastic, the second is abnormally elastic and the third is abnormally dense. The degree of filling with inclusions of each rank for all three hierarchical inclusions is different. Modeling is carried out from smaller sizes to large inclusions;as a result, it becomes possible to determine the necessary parameters of the formed material from acoustic monitoring data. 展开更多
关键词 Nano hierarchic Objects algorithms of Modeling Integral-Differential Equations Iterative Process Block Layered Medium Combined Hiererachical
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An Approach to Assembly Sequence Plannning Based on Hierarchical Strategy and Genetic Algorithm
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作者 Niu Xinwen ,Ding Han,Xiong Youlun School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China Manufacturing and Production 《Computer Aided Drafting,Design and Manufacturing》 2001年第2期8-14,共7页
Using group and subassembly cluster methods, the hierarchical structure of a product is ?generated automatically, which largely reduces the complexity of planning. Based on genetic algorithm, the optimal of assembly s... Using group and subassembly cluster methods, the hierarchical structure of a product is ?generated automatically, which largely reduces the complexity of planning. Based on genetic algorithm, the optimal of assembly sequence of each structure level can be obtained by sequence-by-sequence search. As a result, a better assembly sequence of the product can be generated by combining the assembly sequences of all hierarchical structures, which provides more parallelism and flexibility for assembly operations. An industrial example is solved by this new approach. 展开更多
关键词 assembly sequence planning hierarchical strategy genetic algorithm
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基于路网压缩策略的改进Highway Hierarchical算法 被引量:1
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作者 蔡文学 周兴 +1 位作者 许靖 钟慧玲 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2012年第11期1654-1659,共6页
针对Highway Hierarchical算法中存在的路网压缩成环问题、预处理数据存储问题和完整最短路计算问题,采用无环压缩策略、分层存储策略和局部最短路存储策略,对算法进行了改进.广东省路网测试结果表明,改进后的算法在时间效率上约是原算... 针对Highway Hierarchical算法中存在的路网压缩成环问题、预处理数据存储问题和完整最短路计算问题,采用无环压缩策略、分层存储策略和局部最短路存储策略,对算法进行了改进.广东省路网测试结果表明,改进后的算法在时间效率上约是原算法的5倍,在空间效率上约是原算法的4倍. 展开更多
关键词 压缩路网 HIGHWAY hierarchical算法 路径规划
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Exploring on Hierarchical Kalman Filtering Fusion Accuracy
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作者 罗森林 张鹤飞 潘丽敏 《Journal of Beijing Institute of Technology》 EI CAS 1998年第4期373-379,共7页
Aim To analyze the traditional hierarchical Kalman filtering fusion algorithm theoretically and point out that the traditional Kalman filtering fusion algorithm is complex and can not improve the tracking precision we... Aim To analyze the traditional hierarchical Kalman filtering fusion algorithm theoretically and point out that the traditional Kalman filtering fusion algorithm is complex and can not improve the tracking precision well, even it is impractical, and to propose the weighting average fusion algorithm. Methods The theoretical analysis and Monte Carlo simulation methods were ed to compare the traditional fusion algorithm with the new one,and the comparison of the root mean square error statistics values of the two algorithms was made. Results The hierarchical fusion algorithm is not better than the weighting average fusion and feedback weighting average algorithm The weighting filtering fusion algorithm is simple in principle, less in data, faster in processing and better in tolerance.Conclusion The weighting hierarchical fusion algorithm is suitable for the defective sensors.The feedback of the fusion result to the single sersor can enhance the single sensorr's precision. especially once one sensor has great deviation and low accuracy or has some deviation of sample period and is asynchronous to other sensors. 展开更多
关键词 Kalman filtering hierarchical fusion algorithm weighting average feedback fusion algorithm
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Hierarchical resource allocation for integrated modular avionics systems 被引量:8
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作者 Tianran Zhou Huagang Xiong Zhen Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第5期780-787,共8页
Recently the integrated modular avionics (IMA) architecture which introduces the concept of resource partitioning becomes popular as an alternative to the traditional federated architecture. A novel hierarchical app... Recently the integrated modular avionics (IMA) architecture which introduces the concept of resource partitioning becomes popular as an alternative to the traditional federated architecture. A novel hierarchical approach is proposed to solve the resource allocation problem for IMA systems in distributed environments. Firstly, the worst case response time of tasks with arbitrary deadlines is analyzed for the two-level scheduler. Then, the hierarchical resource allocation approach is presented in two levels. At the platform level, a task assignment algorithm based on genetic simulated annealing (GSA) is proposed to assign a set of pre-defined tasks to different processing nodes in the form of task groups, so that resources can be allocated as partitions and mapped to task groups. While yielding to all the resource con- straints, the algorithm tries to find an optimal task assignment with minimized communication costs and balanced work load. At the node level, partition parameters are optimized, so that the computational resource can be allocated further. An example is shown to illustrate the hierarchal resource allocation approach and manifest the validity. Simulation results comparing the performance of the proposed GSA with that of traditional genetic algorithms are presented in the context of task assignment in IMA systems. 展开更多
关键词 avionics system engineering integrated modular avionics (IMA) resource allocation hierarchical scheduling genetic algorithm (GA) simulated annealing algorithm.
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Asymmetric electric field distribution enhanced hierarchical metamaterials for radar-infrared compatible camouflage 被引量:5
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作者 Tuo Zhang Yuping Duan +4 位作者 Jiangyong Liu Hao Lei Jingxuan Sun Huifang Pang Lingxi Huang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第15期10-18,共9页
Metamaterials are widely used in electromagnetic radiation and camouflage for their flexible wavefront manipulation and polarization over a broad spectrum ranging from microwaves to optics.However,multispectral compat... Metamaterials are widely used in electromagnetic radiation and camouflage for their flexible wavefront manipulation and polarization over a broad spectrum ranging from microwaves to optics.However,multispectral compatible camouflage faces significant challenges due to tremendous scale differences of unit cells and desired radiative properties in various spectral regimes.This study assembles a micron-scale infrared emitter,a millimeter-scale microwave absorber,and a metal reflector to propose a hierarchical metamaterial that reduces microwave scattering and reflects low-infrared waves.As a proof of concept,laser etching micro-manufactures an upper infrared shielding layer with a periodic metal pattern.At the same time,bottom square frustum metastructure composites are fabricated and optimized based on genetic algorithms.Under the normal incidence transverse electromagnetic wave with a 90°azimuth angle,the hierarchical strategy and infrared unit create an asymmetric electric field distribution of local near-field coupling,which is conducive to generating additional resonance for broadening the absorption bandwidth.Experiments verify the multispectral camouflage,which shows a high absorption efficiency of more than 90%,ranging from 3.6 to 6.2 and from 8.4 to 18 GHz with a total thickness of 4.05 mm(0.049λmax).Due to the non-reflection of surrounding thermal signals in the infrared 2-22μm region,low-infrared emissivity(0.29)metamaterials can adapt to various thermal backgrounds.This methodology can provide a novel route for fabricating multispectral camouflage devices. 展开更多
关键词 hierarchical metamaterials Radar-infrared compatible stealth Genetic algorithm Magnetic-dielectric lossy composites Asymmetry
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A Novel Stable Clustering Design Method for Hierarchical Satellite Network 被引量:1
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作者 Zhou Mu,Guo Qing,Wang Zhenyong Communication Research Center,School of Electronics and Information Engineering,Harbin Institute of Technology,Harbin 150001,China 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2010年第1期91-102,共12页
This article proposes a novel stable clustering design method for hierarchical satellite network in order to increase its stability,reduce the overhead of storage and exert effective control of the delay performances ... This article proposes a novel stable clustering design method for hierarchical satellite network in order to increase its stability,reduce the overhead of storage and exert effective control of the delay performances based on a 5-dimensional vector model. According to the function of stability measureinent and owing to the limitation of minimal average routing table length, the hierarchical satellite network is grouped into separate stable connected clusters to improve destruction resistance and reconstruction ability in the future integrated network. In each cluster, redundant communication links with little contribution to network stability and slight influences on delay variation are deleted to satisfy the requirements for stability and connectivity by means of optimal link resources, and, also, the idea of logical weight is introduced to select the optimal satellites used to communicate with neighboring cluster satellites. Finally, the feasibility and effectiveness of the proposed method are verified by comparing it with the simulated performances of other two typical hierarchical satellite networks, double layer satellite constellation(DLSC) and satellite over satellite(SOS). 展开更多
关键词 satellite network hierarchical structure stability analysis clustering algorithms vector measurements
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Handling Multiple Objectives with Biogeography-based Optimization 被引量:3
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作者 Hai-Ping Ma Xie-Yong Ruan Zhang-Xin Pan 《International Journal of Automation and computing》 EI 2012年第1期30-36,共7页
Biogeography-based optimization (BBO) is a new evolutionary optimization method inspired by biogeography. In this paper, BBO is extended to a multi-objective optimization, and a biogeography-based multi-objective op... Biogeography-based optimization (BBO) is a new evolutionary optimization method inspired by biogeography. In this paper, BBO is extended to a multi-objective optimization, and a biogeography-based multi-objective optimization (BBMO) is introduced, which uses the cluster attribute of islands to naturally decompose the problem. The proposed algorithm makes use of nondominated sorting approach to improve the convergence ability efficiently. It also combines the crowding distance to guarantee the diversity of Pareto optimal solutions. We compare the BBMO with two representative state-of-the-art evolutionary multi-objective optimization methods, non-dominated sorting genetic algorithm-II (NSGA-II) and archive-based micro genetic algorithm (AMGA) in terms of three metrics. Simulation results indicate that in most cases, the proposed BBMO is able to find much better spread of solutions and converge faster to true Pareto optimal fronts than NSGA-II and AMGA do. 展开更多
关键词 Multi-objective optimization biogeography-based optimization (BBO) evolutionary algorithms Pareto optimal nondominated sorting.
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Analyzing the Urban Hierarchical Structure Based on Multiple Indicators of Economy and Industry: An Econometric Study in China 被引量:1
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作者 Jing Cheng Yang Xie Jie Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第6期1831-1855,共25页
For a city,analyzing its advantages,disadvantages and the level of economic development in a country is important,especially for the cities in China developing at flying speed.The corresponding literatures for the cit... For a city,analyzing its advantages,disadvantages and the level of economic development in a country is important,especially for the cities in China developing at flying speed.The corresponding literatures for the cities in China have not considered the indicators of economy and industry in detail.In this paper,based on multiple indicators of economy and industry,the urban hierarchical structure of 285 cities above the prefecture level in China is investigated.The indicators from the economy,industry,infrastructure,medical care,population,education,culture,and employment levels are selected to establish a new indicator system for analyzing urban hierarchical structure.The factor analysis method is used to investigate the relationship between the variables of selected indicators and obtain the score of each common factor and comprehensive scores and rankings for 285 cities above the prefecture level in China.According to the comprehensive scores,285 cities above the prefecture level are clustered into 15 levels by using K-means clustering algorithm.Then,the hierarchical structure system of the cities above the prefecture level in China is obtained and corresponding policy implications are proposed.The results and implications can not only be applied to the urban planning and development in China but also offer a reference on other developing countries.The methodologies used in this paper can also be applied to study the urban hierarchical structure in other countries. 展开更多
关键词 Urban planning hierarchical structure prefecture-level city factor analysis method K-means clustering algorithm China
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