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Topological optimization of metamaterial absorber based on improved estimation of distribution algorithm
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作者 TAO Shifei LIU Beichen +2 位作者 LIU Sixing WU Fan WANG Hao 《Journal of Systems Engineering and Electronics》 2025年第3期634-641,共8页
An improved estimation of distribution algorithm(IEDA)is proposed in this paper for efficient design of metamaterial absorbers.This algorithm establishes a probability model through the selected dominant groups and sa... An improved estimation of distribution algorithm(IEDA)is proposed in this paper for efficient design of metamaterial absorbers.This algorithm establishes a probability model through the selected dominant groups and samples from the model to obtain the next generation,avoiding the problem of building-blocks destruction caused by crossover and mutation.Neighboring search from artificial bee colony algorithm(ABCA)is introduced to enhance the local optimization ability and improved to raise the speed of convergence.The probability model is modified by boundary correction and loss correction to enhance the robustness of the algorithm.The proposed IEDA is compared with other intelligent algorithms in relevant references.The results show that the proposed IEDA has faster convergence speed and stronger optimization ability,proving the feasibility and effectiveness of the algorithm. 展开更多
关键词 METAMATERIAL topological optimization estimation of distribution algorithm
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Archimedean copula estimation of distribution algorithm based on artificial bee colony algorithm 被引量:8
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作者 Haidong Xu Mingyan Jiang Kun Xu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第2期388-396,共9页
The artificial bee colony (ABC) algorithm is a com- petitive stochastic population-based optimization algorithm. How- ever, the ABC algorithm does not use the social information and lacks the knowledge of the proble... The artificial bee colony (ABC) algorithm is a com- petitive stochastic population-based optimization algorithm. How- ever, the ABC algorithm does not use the social information and lacks the knowledge of the problem structure, which leads to in- sufficiency in both convergent speed and searching precision. Archimedean copula estimation of distribution algorithm (ACEDA) is a relatively simple, time-economic and multivariate correlated EDA. This paper proposes a novel hybrid algorithm based on the ABC algorithm and ACEDA called Archimedean copula estima- tion of distribution based on the artificial bee colony (ACABC) algorithm. The hybrid algorithm utilizes ACEDA to estimate the distribution model and then uses the information to help artificial bees to search more efficiently in the search space. Six bench- mark functions are introduced to assess the performance of the ACABC algorithm on numerical function optimization. Experimen- tal results show that the ACABC algorithm converges much faster with greater precision compared with the ABC algorithm, ACEDA and the global best (gbest)-guided ABC (GABC) algorithm in most of the experiments. 展开更多
关键词 artificial bee colony(ABC) algorithm Archimedean copula estimation of distribution algorithm(ACEDA) ACEDA based on artificial be
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An improved estimation of distribution algorithm for multi-compartment electric vehicle routing problem 被引量:6
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作者 SHEN Yindong PENG Liwen LI Jingpeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第2期365-379,共15页
The multi-compartment electric vehicle routing problem(EVRP)with soft time window and multiple charging types(MCEVRP-STW&MCT)is studied,in which electric multi-compartment vehicles that are environmentally friendl... The multi-compartment electric vehicle routing problem(EVRP)with soft time window and multiple charging types(MCEVRP-STW&MCT)is studied,in which electric multi-compartment vehicles that are environmentally friendly but need to be recharged in course of transport process,are employed.A mathematical model for this optimization problem is established with the objective of minimizing the function composed of vehicle cost,distribution cost,time window penalty cost and charging service cost.To solve the problem,an estimation of the distribution algorithm based on Lévy flight(EDA-LF)is proposed to perform a local search at each iteration to prevent the algorithm from falling into local optimum.Experimental results demonstrate that the EDA-LF algorithm can find better solutions and has stronger robustness than the basic EDA algorithm.In addition,when comparing with existing algorithms,the result shows that the EDA-LF can often get better solutions in a relatively short time when solving medium and large-scale instances.Further experiments show that using electric multi-compartment vehicles to deliver incompatible products can produce better results than using traditional fuel vehicles. 展开更多
关键词 multi-compartment vehicle routing problem electric vehicle routing problem(EVRP) soft time window multiple charging type estimation of distribution algorithm(EDA) Lévy flight
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Gaussian process assisted coevolutionary estimation of distribution algorithm for computationally expensive problems 被引量:2
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作者 罗娜 钱锋 +1 位作者 赵亮 钟伟民 《Journal of Central South University》 SCIE EI CAS 2012年第2期443-452,共10页
In order to reduce the computation of complex problems, a new surrogate-assisted estimation of distribution algorithm with Gaussian process was proposed. Coevolution was used in dual populations which evolved in paral... In order to reduce the computation of complex problems, a new surrogate-assisted estimation of distribution algorithm with Gaussian process was proposed. Coevolution was used in dual populations which evolved in parallel. The search space was projected into multiple subspaces and searched by sub-populations. Also, the whole space was exploited by the other population which exchanges information with the sub-populations. In order to make the evolutionary course efficient, multivariate Gaussian model and Gaussian mixture model were used in both populations separately to estimate the distribution of individuals and reproduce new generations. For the surrogate model, Gaussian process was combined with the algorithm which predicted variance of the predictions. The results on six benchmark functions show that the new algorithm performs better than other surrogate-model based algorithms and the computation complexity is only 10% of the original estimation of distribution algorithm. 展开更多
关键词 estimation of distribution algorithm fitness function modeling Gaussian process surrogate approach
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A novel hybrid estimation of distribution algorithm for solving hybrid flowshop scheduling problem with unrelated parallel machine 被引量:10
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作者 孙泽文 顾幸生 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第8期1779-1788,共10页
The hybrid flow shop scheduling problem with unrelated parallel machine is a typical NP-hard combinatorial optimization problem, and it exists widely in chemical, manufacturing and pharmaceutical industry. In this wor... The hybrid flow shop scheduling problem with unrelated parallel machine is a typical NP-hard combinatorial optimization problem, and it exists widely in chemical, manufacturing and pharmaceutical industry. In this work, a novel mathematic model for the hybrid flow shop scheduling problem with unrelated parallel machine(HFSPUPM) was proposed. Additionally, an effective hybrid estimation of distribution algorithm was proposed to solve the HFSPUPM, taking advantage of the features in the mathematic model. In the optimization algorithm, a new individual representation method was adopted. The(EDA) structure was used for global search while the teaching learning based optimization(TLBO) strategy was used for local search. Based on the structure of the HFSPUPM, this work presents a series of discrete operations. Simulation results show the effectiveness of the proposed hybrid algorithm compared with other algorithms. 展开更多
关键词 hybrid estimation of distribution algorithm teaching learning based optimization strategy hybrid flow shop unrelated parallel machine scheduling
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Dual CG-IG distribution model for sea clutter and its parameter correction method
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作者 LI Zhen HE Huafeng +3 位作者 ZHOU Tao ZHANG Qi HAN Xiaofei YOU Yongquan 《Journal of Systems Engineering and Electronics》 2025年第5期1177-1187,共11页
Accurate modeling and parameter estimation of sea clutter are fundamental for effective sea surface target detection.With the improvement of radar resolution,sea clutter exhibits a pronounced heavy-tailed characterist... Accurate modeling and parameter estimation of sea clutter are fundamental for effective sea surface target detection.With the improvement of radar resolution,sea clutter exhibits a pronounced heavy-tailed characteristic,rendering traditional distribution models and parameter estimation methods less effective.To address this,this paper proposes a dual compound-Gaussian model with inverse Gaussian texture(CG-IG)distribution model and combines it with an improved Adam algorithm to introduce a method for parameter correction.This method effectively fits sea clutter with heavy-tailed characteristics.Experiments with real measured sea clutter data show that the dual CGIG distribution model,after parameter correction,accurately describes the heavy-tailed phenomenon in sea clutter amplitude distribution,and the overall mean square error of the distribution is reduced. 展开更多
关键词 compound-Gaussian model with inverse Gaussian texture(CG-IG)distribution sea clutter Adam algorithm parameter estimation
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Dynamic threshold for SPWVD parameter estimation based on Otsu algorithm 被引量:11
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作者 Ning Ma Jianxin Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第6期919-924,共6页
Time-frequency-based methods are proven to be effective for parameter estimation of linear frequency modulation (LFM) signals. The smoothed pseudo Winger-Ville distribution (SPWVD) is used for the parameter estima... Time-frequency-based methods are proven to be effective for parameter estimation of linear frequency modulation (LFM) signals. The smoothed pseudo Winger-Ville distribution (SPWVD) is used for the parameter estimation of multi-LFM signals, and a method of the SPWVD binarization by a dynamic threshold based on the Otsu algorithm is proposed. The proposed method is effective in the demand for the estimation of different parameters and the unknown signal-to-noise ratio (SNR) circumstance. The performance of this method is confirmed by numerical simulation. 展开更多
关键词 parameter estimation smoothed pseudo Winger-Ville distribution (SPWVD) dynamic threshold otsu algorithm
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State simulation of water distribution networks based on DFP algorithm
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作者 张卉 黄廷林 何文杰 《Journal of Central South University》 SCIE EI CAS 2009年第S1期298-303,共6页
The improved weighted-least-square model was used for state simulation of water distribution networks. And DFP algorithm was applied to get the model solution. In order to fit DFP algorithm,the initial model was trans... The improved weighted-least-square model was used for state simulation of water distribution networks. And DFP algorithm was applied to get the model solution. In order to fit DFP algorithm,the initial model was transformed into a non-constrained optimization problem using mass conservation. Then,through one dimensional optimization and scale matrix establishment,the feasible direction of iteration was obtained,and the values of state variables could be calculated. After several iterations,the optimal estimates of state variables were worked out and state simulation of water distribution networks was achieved as a result. A program of DFP algorithm is developed with Delphi 7 for verification. By running on a designed network,which is composed of 55 nodes,94 pipes and 40 loops,it is proved that DFP algorithm can quickly get the convergence. After 36 iterations,the root mean square of all nodal head errors is reduced by 90.84% from 5.57 to 0.51 m,and the maximum error is only 1.30 m. Compared to Marquardt algorithm,the procedure of DFP algorithm is more stable,and the initial values have less influences on calculation accuracy. Therefore,DFP algorithm can be used for real-time simulation of water distribution networks. 展开更多
关键词 water distribution NETWoRK STATE SIMULATIoN STATE estimation DFP algorithm
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Adaptive Multisensor Tracking Fusion Algorithm for Air-borne Distributed Passive Sensor Network
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作者 Zhen Ding Hongcai Zhang & Guanzhong Dai (Department of Automatic Control, Northwestern Polytechnical UniversityShaanxi, Xi’an 710072, P.R.China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1996年第3期15-23,共9页
Single passive sensor tracking algorithms have four disadvantages: bad stability, longdynamic time, big bias and sensitive to initial conditions. So the corresponding fusion algorithm results in bad performance. A new... Single passive sensor tracking algorithms have four disadvantages: bad stability, longdynamic time, big bias and sensitive to initial conditions. So the corresponding fusion algorithm results in bad performance. A new error analysis method for two passive sensor tracking system is presented and the error equations are deduced in detail. Based on the equations, we carry out theoretical computation and Monte Carlo computer simulation. The results show the correctness of our error computation equations. With the error equations, we present multiple 'two station'fusion algorithm using adaptive pseudo measurement equations. This greatly enhances the tracking performance and makes the algorithm convergent very fast and not sensitive to initial conditions.Simulation results prove the correctness of our new algorithm. 展开更多
关键词 Passive tracking system Error analysis Fusion algorithm distributed passive sensornetwork distributed estimation.
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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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Distributed localization for anchor-free sensor networks 被引量:9
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作者 Cui Xunxue Shan Zhiguan Liu Jianjun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第3期405-418,共14页
Geographic location of nodes is very useful in a sensor network. Previous localization algorithms assume that there exist some anchor nodes in this kind of network, and then other nodes are estimated to create their c... Geographic location of nodes is very useful in a sensor network. Previous localization algorithms assume that there exist some anchor nodes in this kind of network, and then other nodes are estimated to create their coordinates. Once there are not anchors to be deployed, those localization algorithms will be invalidated. Many papers in this field focus on anchor-based solutions. The use of anchors introduces many limitations, since anchors require external equipments such as global position system, cause additional power consumption. A novel positioning algorithm is proposed to use a virtual coordinate system based on a new concept--virtual anchor. It is executed in a distributed fashion according to the connectivity of a node and the measured distances to its neighbors. Both the adjacent member information and the ranging distance result are combined to generate the estimated position of a network, one of which is independently adopted for localization previously. At the position refinement stage the intermediate estimation of a node begins to be evaluated on its reliability for position mutation; thus the positioning optimization process of the whole network is avoided falling into a local optimal solution. Simulation results prove that the algorithm can resolve the distributed localization problem for anchor-free sensor networks, and is superior to previous methods in terms of its positioning capability under a variety of circumstances. 展开更多
关键词 anchor-free localization distributed algorithm position estimation sensor networks.
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基于修正q-威布尔分布的矿用卡车可靠性分析
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作者 刘威 高琪 +2 位作者 刘光伟 白润才 朱乙鑫 《辽宁工程技术大学学报(自然科学版)》 北大核心 2025年第2期237-246,共10页
为了更加准确地描述露天矿矿用卡车的失效规律,提高可靠性分析的准确性,构建了一种新的alpha变换。在此基础上,提出了一种四参数修正q-威布尔分布模型,并采用蜣螂优化算法与极大似然估计相结合的方式对模型的参数进行估计。通过实例对... 为了更加准确地描述露天矿矿用卡车的失效规律,提高可靠性分析的准确性,构建了一种新的alpha变换。在此基础上,提出了一种四参数修正q-威布尔分布模型,并采用蜣螂优化算法与极大似然估计相结合的方式对模型的参数进行估计。通过实例对比验证了使用修正q-威布尔分布模型评估矿用卡车可靠性的合理性和有效性。数值试验结果表明,利用修正q-威布尔分布模型对矿用卡车故障间隔时间进行分析,制定相应的预防性维修周期能够更好地保障矿用卡车安全、稳定运行。 展开更多
关键词 矿用卡车 可靠性分析 修正q-威布尔分布 蜣螂优化算法 预防性维修周期 极大似然估计
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考虑并网监测信息的有源配电网μPMU优化配置
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作者 梁振锋 田雨鑫 +1 位作者 闫俊杰 王晓卫 《电力系统及其自动化学报》 北大核心 2025年第3期66-74,共9页
为提高有源配电网状态估计精度,提出一种考虑并网监测信息的微型同步相量测量单元优化配置方法。分析有源配电网数据终端单元、分布式电源和电动汽车并网点监测装置、高级量测体系及微型同步相量测量单元等量测信息特征,建立以混合状态... 为提高有源配电网状态估计精度,提出一种考虑并网监测信息的微型同步相量测量单元优化配置方法。分析有源配电网数据终端单元、分布式电源和电动汽车并网点监测装置、高级量测体系及微型同步相量测量单元等量测信息特征,建立以混合状态估计平均绝对误差最小为目标函数、以微型同步相量测量单元安装数目和状态估计最大允许误差为约束条件的微型同步相量测量单元优化配置模型,并采用粒子群优化算法求解。算例分析表明,考虑并网点监测数据能有效提升状态估计精度,且可减少微型同步相量测量单元的配置数量。 展开更多
关键词 并网点监测 有源配电网 微型同步相量测量单元 优化配置 状态估计 粒子群优化算法
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面向非独立同分布数据的迭代式联邦学习 被引量:1
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作者 陈洪洋 李晓会 王天阳 《计算机工程与设计》 北大核心 2025年第4期1064-1071,共8页
针对现有的面向非独立同分布(non-IID)数据的联邦学习优化算法存在训练的模型缺失个性化、模型在测试集上精度较低的问题,提出一种迭代凝聚式簇估计联邦学习算法FL-ICE(iterative cluster estimation federated)。各个客户端联合训练单... 针对现有的面向非独立同分布(non-IID)数据的联邦学习优化算法存在训练的模型缺失个性化、模型在测试集上精度较低的问题,提出一种迭代凝聚式簇估计联邦学习算法FL-ICE(iterative cluster estimation federated)。各个客户端联合训练单个全局共享模型,迭代地依据客户端更新的相似度执行簇估计并通过梯度下降优化簇估计参数,对全局模型进行个性化处理。实验结果表明,该算法可以有效提升模型在测试集上的准确性,使得更大比例的客户端达到目标精度。 展开更多
关键词 联邦学习 分布式机器学习 个性化模型 迭代式训练 簇估计算法 非独立同分布数据 隐私保护
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对称稳定分布噪声下基于广义相关熵的DOA估计新方法 被引量:11
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作者 王鹏 邱天爽 +2 位作者 任福全 李景春 谭海峰 《电子与信息学报》 EI CSCD 北大核心 2016年第8期2007-2013,共7页
针对稳定随机变量有限二阶矩不存在的特点,该文定义了一种新的广义相关熵,并从理论上证明了对称稳定分布随机变量广义相关熵的有界性。此外,提出了一种稳定分布噪声下基于最小广义相关熵准则的DOA估计新方法,给出了一种迭代优化算法并... 针对稳定随机变量有限二阶矩不存在的特点,该文定义了一种新的广义相关熵,并从理论上证明了对称稳定分布随机变量广义相关熵的有界性。此外,提出了一种稳定分布噪声下基于最小广义相关熵准则的DOA估计新方法,给出了一种迭代优化算法并通过仿真实验分析了算法的收敛性。仿真结果表明,与现有基于分数低阶矩的FLOM-MUSIC、基于类相关熵的CRCO-MUSIC以及基于lp范数的ACO-MUSIC算法相比,所提方法可以获得更好的估计结果,尤其是在高脉冲性噪声环境下具有更加明显的优势。 展开更多
关键词 波达方向估计 相关熵 广义相关熵 稳定分布噪声 MUSIC算法
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基于支持向量机与高斯分布估计的低NOx排放 被引量:8
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作者 梁绍华 郑立刚 +1 位作者 周昊 岑可法 《化工学报》 EI CAS CSCD 北大核心 2009年第1期223-229,共7页
燃烧优化的核心在于建立有效而快速的建模工具及寻优算法,以便于在线应用。为了研究新方法的适用性以及克服常用算法的缺点,本文利用支持向量回归建立了大型四角切圆燃烧电站锅炉NOx排放特性模型。利用大量的热态实炉试验NOx排放数据对... 燃烧优化的核心在于建立有效而快速的建模工具及寻优算法,以便于在线应用。为了研究新方法的适用性以及克服常用算法的缺点,本文利用支持向量回归建立了大型四角切圆燃烧电站锅炉NOx排放特性模型。利用大量的热态实炉试验NOx排放数据对模型进行了训练和验证。结果表明,支持向量回归模型能获得较神经网络模型更加准确的预测结果,相对于神经网络,支持向量回归能更好处理大样本量数据的非线性问题。随后,采用一种基于高斯概率密度(GPDD)的分布估计优化算法对NOx排放模型进行了寻优。研究发现,与遗传算法相比,GPDD具有更好的寻优能力与更快的收敛速度。结合支持向量回归与高斯概率密度分布(GPDD)算法能有效降低燃煤锅炉NOx排放量,不到1min的优化时间便于在线应用。研究结论可为该算法在实际电厂中推广应用提供参考依据。 展开更多
关键词 燃烧优化 Nox 支持向量回归 高斯概率密度分布 分布估计算法
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一种基于Alopex和分布估计算法融合的进化算法及其在参数估计中的应用 被引量:4
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作者 李飞 李绍军 梅真贞 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2011年第7期1973-1980,共8页
构造了一种基于Alopex(Algorithm of pattern extraction)和分布估计算法(Estimation of distribution algorithm,EDA)相融合的进化算法EDA-Alopex。该算法将分布估计算法嵌入到一种基于Alopex的群智能进化算法(Alopex-based evolutiona... 构造了一种基于Alopex(Algorithm of pattern extraction)和分布估计算法(Estimation of distribution algorithm,EDA)相融合的进化算法EDA-Alopex。该算法将分布估计算法嵌入到一种基于Alopex的群智能进化算法(Alopex-based evolutionary algorithm,AEA)中,利用分布估计算法收敛速度快及与传统进化算法进化模式不同的特点来改进AEA算法。新算法综合了AEA算法搜索得到的个体间相关性信息和EDA搜索过程中得到的全局概率信息,能够更好地指导种群向有利的区域进化。仿真结果表明:EDA改进的EDA-Alopex算法搜索性能与AEA算法的搜索性能相比有较大提高,特别是其收敛速度与AEA算法相比有明显提高。 展开更多
关键词 ALoPEX 分布估计算法 函数优化 参数估计
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一种动态融合的并行混合进化算法EDAs/PSO 被引量:2
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作者 仇丽青 梁永全 樊建聪 《计算机应用与软件》 CSCD 北大核心 2014年第6期271-274,共4页
在介绍分布估计算法和粒子群算法的基础上,提出一种动态融合的并行混合进化算法EDAs/PSO。该算法采用分布估计算法和粒子群算法两种模型,既保持了分布估计算法较强的全局搜索能力,又保持了粒子群算法较强的局部搜索能力;另一方面,又采... 在介绍分布估计算法和粒子群算法的基础上,提出一种动态融合的并行混合进化算法EDAs/PSO。该算法采用分布估计算法和粒子群算法两种模型,既保持了分布估计算法较强的全局搜索能力,又保持了粒子群算法较强的局部搜索能力;另一方面,又采用一种动态融合的并行策略,通过周期性地对子种群中的个体按照一定的迁移率进行迁移操作,保证了种群的多样性,从而防止了算法的早熟收敛,提高了解的精度。实验结果表明了该算法的有效性和正确性。 展开更多
关键词 进化算法 分布估计算法 粒子群算法EDAs PSo
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OFDM系统中一种改进的快衰落信道估计算法 被引量:5
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作者 孙翠珍 曾召华 《西安科技大学学报》 CAS 北大核心 2008年第1期128-131,共4页
在OFDM系统中,由于无线信道的随机性,在一个OFDM符号帧内,信道特性会发生明显的变化,OFDM符号会产生子载波间干扰,并且一个OFDM符号边缘的子载波受到的影响比较大,正交频分复用系统中导频符号由于采用了均匀分布的方案,造成信道估计算... 在OFDM系统中,由于无线信道的随机性,在一个OFDM符号帧内,信道特性会发生明显的变化,OFDM符号会产生子载波间干扰,并且一个OFDM符号边缘的子载波受到的影响比较大,正交频分复用系统中导频符号由于采用了均匀分布的方案,造成信道估计算法的误码率较大。本论文提出了一种非均匀分布的导频分布方案,利用牛顿插值算法分别计算导频符号边缘和中央的间距,再进行信道估计算法。并且在仿真参数相同的条件下,在均匀分布和本论文提出的非均匀分布的方案的基础上,对信道估计算法进行了matlab仿真,结果表明:改进后的方案与原来方案相比,具有更好的估计性能,尤其在移动台高速移动时候更有优越性,表明了改进后的方案更适合第四代移动通信的高速要求。 展开更多
关键词 正交频分复用 随机性 信道估计 导频 牛顿插值算法 非均匀分布
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Copula分布估计算法在瞬时单位线参数估计中的应用 被引量:1
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作者 朱从飞 陆宝宏 +2 位作者 庄德利 刘欢 左建 《水电能源科学》 北大核心 2015年第12期28-31,共4页
针对利用传统矩法估计瞬时单位线参数时还原的洪水过程与实测洪水过程之间往往存在较大差异的问题,结合Copula函数与分布估计算法的优点,以实测地面径流与还原地面径流的加权残差绝对值之和最小为准则,采用Copula分布估计算法进行流域... 针对利用传统矩法估计瞬时单位线参数时还原的洪水过程与实测洪水过程之间往往存在较大差异的问题,结合Copula函数与分布估计算法的优点,以实测地面径流与还原地面径流的加权残差绝对值之和最小为准则,采用Copula分布估计算法进行流域瞬时单位线的参数估计,这样既保证了算法的全局搜索能力,又充分考虑了参数间的相关关系。实例应用结果表明,利用Copula分布估计算法估计单位线,还原后的洪水过程与实测洪水过程的吻合度较传统的矩法高,特别是对于洪峰,优势更为明显。 展开更多
关键词 瞬时单位线 参数估计 分布估计算法 CoPULA理论
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