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Optimized quantum random-walk search algorithm for multi-solution search 被引量:1
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作者 张宇超 鲍皖苏 +1 位作者 汪翔 付向群 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第11期133-139,共7页
This study investigates the multi-solution search of the optimized quantum random-walk search algorithm on the hypercube. Through generalizing the abstract search algorithm which is a general tool for analyzing the se... This study investigates the multi-solution search of the optimized quantum random-walk search algorithm on the hypercube. Through generalizing the abstract search algorithm which is a general tool for analyzing the search on the graph to the multi-solution case, it can be applied to analyze the multi-solution case of quantum random-walk search on the graph directly. Thus, the computational complexity of the optimized quantum random-walk search algorithm for the multi-solution search is obtained. Through numerical simulations and analysis, we obtain a critical value of the proportion of solutions q. For a given q, we derive the relationship between the success rate of the algorithm and the number of iterations when q is no longer than the critical value. 展开更多
关键词 quantum search algorithm quantum random walk multi-solution abstract search algorithm
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AN ANALYSIS ABOUT BEHAVIOR OF EVOLUTIONARY ALGORITHMS:A KIND OF THEORETICAL DESCRIPTION BASED ON GLOBAL RANDOM SEARCH METHODS 被引量:1
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作者 Ding Lixin Kang Lishan +1 位作者 Chen Yupin Zhou Shaoquan 《Wuhan University Journal of Natural Sciences》 CAS 1998年第1期31-31,共1页
Evolutionary computation is a kind of adaptive non--numerical computation method which is designed tosimulate evolution of nature. In this paper, evolutionary algorithm behavior is described in terms of theconstructio... Evolutionary computation is a kind of adaptive non--numerical computation method which is designed tosimulate evolution of nature. In this paper, evolutionary algorithm behavior is described in terms of theconstruction and evolution of the sampling distributions over the space of candidate solutions. Iterativeconstruction of the sampling distributions is based on the idea of the global random search of generationalmethods. Under this frame, propontional selection is characterized as a gobal search operator, and recombination is characerized as the search process that exploits similarities. It is shown-that by properly constraining the search breadth of recombination operators, weak convergence of evolutionary algorithms to aglobal optimum can be ensured. 展开更多
关键词 global random search evolutionary algorithms weak convergence genetic algorithms
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Decoherence in optimized quantum random-walk search algorithm 被引量:1
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作者 张宇超 鲍皖苏 +1 位作者 汪翔 付向群 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第8期197-202,共6页
This paper investigates the effects of decoherence generated by broken-link-type noise in the hypercube on an optimized quantum random-walk search algorithm. When the hypercube occurs with random broken links, the opt... This paper investigates the effects of decoherence generated by broken-link-type noise in the hypercube on an optimized quantum random-walk search algorithm. When the hypercube occurs with random broken links, the optimized quantum random-walk search algorithm with decoherence is depicted through defining the shift operator which includes the possibility of broken links. For a given database size, we obtain the maximum success rate of the algorithm and the required number of iterations through numerical simulations and analysis when the algorithm is in the presence of decoherence. Then the computational complexity of the algorithm with decoherence is obtained. The results show that the ultimate effect of broken-link-type decoherence on the optimized quantum random-walk search algorithm is negative. 展开更多
关键词 quantum search algorithm quantum random walk DECOHERENCE
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Winter Wheat Yield Estimation Based on Sparrow Search Algorithm Combined with Random Forest:A Case Study in Henan Province,China 被引量:1
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作者 SHI Xiaoliang CHEN Jiajun +2 位作者 DING Hao YANG Yuanqi ZHANG Yan 《Chinese Geographical Science》 SCIE CSCD 2024年第2期342-356,共15页
Precise and timely prediction of crop yields is crucial for food security and the development of agricultural policies.However,crop yield is influenced by multiple factors within complex growth environments.Previous r... Precise and timely prediction of crop yields is crucial for food security and the development of agricultural policies.However,crop yield is influenced by multiple factors within complex growth environments.Previous research has paid relatively little attention to the interference of environmental factors and drought on the growth of winter wheat.Therefore,there is an urgent need for more effective methods to explore the inherent relationship between these factors and crop yield,making precise yield prediction increasingly important.This study was based on four type of indicators including meteorological,crop growth status,environmental,and drought index,from October 2003 to June 2019 in Henan Province as the basic data for predicting winter wheat yield.Using the sparrow search al-gorithm combined with random forest(SSA-RF)under different input indicators,accuracy of winter wheat yield estimation was calcu-lated.The estimation accuracy of SSA-RF was compared with partial least squares regression(PLSR),extreme gradient boosting(XG-Boost),and random forest(RF)models.Finally,the determined optimal yield estimation method was used to predict winter wheat yield in three typical years.Following are the findings:1)the SSA-RF demonstrates superior performance in estimating winter wheat yield compared to other algorithms.The best yield estimation method is achieved by four types indicators’composition with SSA-RF)(R^(2)=0.805,RRMSE=9.9%.2)Crops growth status and environmental indicators play significant roles in wheat yield estimation,accounting for 46%and 22%of the yield importance among all indicators,respectively.3)Selecting indicators from October to April of the follow-ing year yielded the highest accuracy in winter wheat yield estimation,with an R^(2)of 0.826 and an RMSE of 9.0%.Yield estimates can be completed two months before the winter wheat harvest in June.4)The predicted performance will be slightly affected by severe drought.Compared with severe drought year(2011)(R^(2)=0.680)and normal year(2017)(R^(2)=0.790),the SSA-RF model has higher prediction accuracy for wet year(2018)(R^(2)=0.820).This study could provide an innovative approach for remote sensing estimation of winter wheat yield.yield. 展开更多
关键词 winter wheat yield estimation sparrow search algorithm combined with random forest(SSA-RF) machine learning multi-source indicator optimal lead time Henan Province China
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Effects of systematic phase errors on optimized quantum random-walk search algorithm
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作者 张宇超 鲍皖苏 +1 位作者 汪翔 付向群 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第6期155-163,共9页
This study investigates the effects of systematic errors in phase inversions on the success rate and number of iterations in the optimized quantum random-walk search algorithm. Using the geometric description of this ... This study investigates the effects of systematic errors in phase inversions on the success rate and number of iterations in the optimized quantum random-walk search algorithm. Using the geometric description of this algorithm, a model of the algorithm with phase errors is established, and the relationship between the success rate of the algorithm, the database size, the number of iterations, and the phase error is determined. For a given database size, we obtain both the maximum success rate of the algorithm and the required number of iterations when phase errors are present in the algorithm. Analyses and numerical simulations show that the optimized quantum random-walk search algorithm is more robust against phase errors than Grover's algorithm. 展开更多
关键词 quantum search algorithm quantum random walk phase errors ROBUSTNESS
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Random Search Algorithm for the Generalized Weber Problem
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作者 Lev Kazakovtsev 《Journal of Software Engineering and Applications》 2012年第12期59-65,共7页
In this paper, we consider the planar multi-facility Weber problem with restricted zones and non-Euclidean distances, propose an algorithm based on the probability changing method (special kind of genetic algorithms) ... In this paper, we consider the planar multi-facility Weber problem with restricted zones and non-Euclidean distances, propose an algorithm based on the probability changing method (special kind of genetic algorithms) and prove its efficiency for approximate solving this problem by replacing the continuous coordinate values by discrete ones. Version of the algorithm for multiprocessor systems is proposed. Experimental results for a high-performance cluster are given. 展开更多
关键词 DISCRETE Optimization WEBER Problem random search GENETIC algorithms Parallel algorithm
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基于Solis-Wets随机搜索算法的变截面板簧优化设计
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作者 李东月 方宗德 +1 位作者 古玉锋 高度 《机械科学与技术》 CSCD 北大核心 2010年第12期1735-1738,共4页
变截面钢板弹簧以片数少、自重轻、吸收振动载荷能力强、疲劳寿命高等优点正逐步取代等截面钢板弹簧。但由于变截面钢板弹簧存在几何非线性、状态非线性等问题,常规的设计方法很难得到一个合适的设计方案。笔者利用APDL语言建立参数化... 变截面钢板弹簧以片数少、自重轻、吸收振动载荷能力强、疲劳寿命高等优点正逐步取代等截面钢板弹簧。但由于变截面钢板弹簧存在几何非线性、状态非线性等问题,常规的设计方法很难得到一个合适的设计方案。笔者利用APDL语言建立参数化的变截面钢板弹簧有限元模型,计算其应力和刚度。利用DAKOTA优化工具包使用Solis-Wets随机搜索算法结合ANSYS有限元分析进行结构参数优化。获得了同时满足许用应力要求和适合刚度约束的质量最轻设计方案。 展开更多
关键词 变截面钢板弹簧 有限元分析 solis-wets随机搜索算法 刚度特性
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Improvement of Pure Random Search in Global Optimization 被引量:1
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作者 Jian-ping1 Peng Ding-hua Shi 《Advances in Manufacturing》 2000年第2期92-95,共4页
In this paper, the improvement of pure random search is studied. By taking some information of the function to be minimized into consideration, the authors propose two stochastic global optimization algorithms. Some n... In this paper, the improvement of pure random search is studied. By taking some information of the function to be minimized into consideration, the authors propose two stochastic global optimization algorithms. Some numerical experiments for the new stochastic global optimization algorithms are presented for a class of test problems. 展开更多
关键词 random search global optimization stochastic global optimization algorithm
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Analytical Comparison of Resource Search Algorithms in Non-DHT Mobile Peer-to-Peer Networks 被引量:1
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作者 Ajay Arunachalam Vinayakumar Ravi +2 位作者 Moez Krichen Roobaea Alroobaea Jehad Saad Alqurni 《Computers, Materials & Continua》 SCIE EI 2021年第7期983-1001,共19页
One of the key challenges in ad-hoc networks is the resource discovery problem.How efciently&quickly the queried resource/object can be resolved in such a highly dynamic self-evolving network is the underlying que... One of the key challenges in ad-hoc networks is the resource discovery problem.How efciently&quickly the queried resource/object can be resolved in such a highly dynamic self-evolving network is the underlying question?Broadcasting is a basic technique in the Mobile Ad-hoc Networks(MANETs),and it refers to sending a packet from one node to every other node within the transmission range.Flooding is a type of broadcast where the received packet is retransmitted once by every node.The naive ooding technique oods the network with query messages,while the random walk scheme operates by contacting subsets of each node’s neighbors at every step,thereby restricting the search space.Many earlier works have mainly focused on the simulation-based analysis of ooding technique,and its variants,in a wired network scenario.Although,there have been some empirical studies in peer-to-peer(P2P)networks,the analytical results are still lacking,especially in the context of mobile P2P networks.In this article,we mathematically model different widely used existing search techniques,and compare with the proposed improved random walk method,a simple lightweight approach suitable for the non-DHT architecture.We provide analytical expressions to measure the performance of the different ooding-based search techniques,and our proposed technique.We analytically derive 3 relevant key performance measures,i.e.,the avg.number of steps needed to nd a resource,the probability of locating a resource,and the avg.number of messages generated during the entire search process. 展开更多
关键词 Mathematical model MANET P2P networks P2P MANET UNSTRUCTURED search algorithms Peer-to-Peer AD-HOC ooding random walk resource discovery content discovery mobile peer-to-peer broadcast PEER
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Improving path planning efficiency for underwater gravity-aided navigation based on a new depth sorting fast search algorithm
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作者 Xiaocong Zhou Wei Zheng +2 位作者 Zhaowei Li Panlong Wu Yongjin Sun 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期285-296,共12页
This study focuses on the improvement of path planning efficiency for underwater gravity-aided navigation.Firstly,a Depth Sorting Fast Search(DSFS)algorithm was proposed to improve the planning speed of the Quick Rapi... This study focuses on the improvement of path planning efficiency for underwater gravity-aided navigation.Firstly,a Depth Sorting Fast Search(DSFS)algorithm was proposed to improve the planning speed of the Quick Rapidly-exploring Random Trees*(Q-RRT*)algorithm.A cost inequality relationship between an ancestor and its descendants was derived,and the ancestors were filtered accordingly.Secondly,the underwater gravity-aided navigation path planning system was designed based on the DSFS algorithm,taking into account the fitness,safety,and asymptotic optimality of the routes,according to the gravity suitability distribution of the navigation space.Finally,experimental comparisons of the computing performance of the ChooseParent procedure,the Rewire procedure,and the combination of the two procedures for Q-RRT*and DSFS were conducted under the same planning environment and parameter conditions,respectively.The results showed that the computational efficiency of the DSFS algorithm was improved by about 1.2 times compared with the Q-RRT*algorithm while ensuring correct computational results. 展开更多
关键词 Depth Sorting Fast search algorithm Underwater gravity-aided navigation Path planning efficiency Quick Rapidly-exploring random Trees*(QRRT*)
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Investigation Effects of Selection Mechanisms for Gravitational Search Algorithm
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作者 Oguz Findik Mustafa Servet Kiran Ismail Babaoglu 《Journal of Computer and Communications》 2014年第4期117-126,共10页
The gravitational search algorithm (GSA) is a population-based heuristic optimization technique and has been proposed for solving continuous optimization problems. The GSA tries to obtain optimum or near optimum solut... The gravitational search algorithm (GSA) is a population-based heuristic optimization technique and has been proposed for solving continuous optimization problems. The GSA tries to obtain optimum or near optimum solution for the optimization problems by using interaction in all agents or masses in the population. This paper proposes and analyzes fitness-based proportional (rou- lette-wheel), tournament, rank-based and random selection mechanisms for choosing agents which they act masses in the GSA. The proposed methods are applied to solve 23 numerical benchmark functions, and obtained results are compared with the basic GSA algorithm. Experimental results show that the proposed methods are better than the basic GSA in terms of solution quality. 展开更多
关键词 Gravitational search algorithm Roulette-Wheel Selection Tournament Selection Rank-Based Selection random Selection Continuous Optimization
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基于高光谱反射成像技术的带荚毛豆虫害检测方法研究
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作者 张芳 高鑫 +1 位作者 田有文 邓照龙 《沈阳农业大学学报》 北大核心 2026年第1期90-99,共10页
[目的]为解决带荚毛豆内部发生食心虫虫害难以识别的问题,基于高光谱反射成像技术对带荚毛豆的食心虫虫害进行检测。[方法]利用高光谱反射成像系统获取带荚毛豆的健康样本和虫害样本数据,采用多元散射校正(Multiplicative Scatter Corre... [目的]为解决带荚毛豆内部发生食心虫虫害难以识别的问题,基于高光谱反射成像技术对带荚毛豆的食心虫虫害进行检测。[方法]利用高光谱反射成像系统获取带荚毛豆的健康样本和虫害样本数据,采用多元散射校正(Multiplicative Scatter Correction,MSC)、标准正态变量变换(Standard Normal Variate,SNV)和卷积平滑(Savitzky Golay,SG)3种预处理方法对450~1000 nm范围的光谱数据进行处理,确定最佳预处理方法。使用竞争性自适应重加权采样算法(Competitive Adaptive Reweighted Sampling,CARS)、连续投影算法(Successive Projections Algorithm,SPA)对预处理后的数据进行特征波长选择,以2种算法筛选的特征数据作为输入,建立随机森林(Random Forest,RF)、K近邻(K-Nearest Neighbors,KNN)、支持向量机(Support Vector Machine,SVM)和梯度提升决策树(Gradient Boosting Decision Tree,GBDT)分类判别模型。为进一步提升模型的分类精度,选择使用RS算法(Random Search,RS)对4个模型进行超参数寻优,建立RS-RF模型、RS-KNN模型、RS-SVM模型和RS-GBDT模型。[结果]经过对比分析,使用RS算法优化后的模型分类检测结果优于未优化的模型,其中CARS-RS-SVM模型分类结果最佳,Acc为96.22%,Pre为96.47%,Recall为96.03%,f1-Score为96.19%,实现了健康与虫害毛豆的精准区分。[结论]高光谱反射成像技术对带荚毛豆内部虫害的总体识别结果较好,表明该技术能够对带荚毛豆食心虫虫害进行高效的检测与判别,为内部虫害检测提供新的思路与方法。 展开更多
关键词 高光谱反射成像 虫害 带荚毛豆 随机搜索算法 SVM
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基于ISSA-RF算法的光伏阵列故障诊断研究
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作者 许桂敏 宋雨航 +2 位作者 相里梦桥 杨亚龙 段晨东 《太阳能学报》 北大核心 2026年第2期111-121,共11页
提出一种基于改进麻雀搜索(ISSA)优化随机森林(RF)的算法,用以提高光伏阵列故障诊断的准确率。首先,通过搭建光伏阵列模拟5种工况,提取故障向量,构造光伏阵列故障数据集。其次,通过测试函数对灰狼搜索算法(GWO)、粒子群算法(PSO)、ISSA... 提出一种基于改进麻雀搜索(ISSA)优化随机森林(RF)的算法,用以提高光伏阵列故障诊断的准确率。首先,通过搭建光伏阵列模拟5种工况,提取故障向量,构造光伏阵列故障数据集。其次,通过测试函数对灰狼搜索算法(GWO)、粒子群算法(PSO)、ISSA和麻雀搜索算法(SSA)进行寻优对比,发现ISSA在平均值和标准差方面均优于其他算法,显示出更好的鲁棒性。然后,利用光伏阵列故障仿真数据集对ISSA-RF诊断模型进行性能分析,得到ISSA-RF方法整体准确率达到97.06%,比传统RF模型提高6.94个百分点。最后,结合实验室光伏阵列开路、短路、遮荫、老化和正常5种工况数据集对ISSA-RF诊断模型进行验证,证明所提基于ISSA-RF的光伏阵列故障诊断方法具有较高的分类效率和精度,其性能表现优于其他诊断模型。 展开更多
关键词 光伏阵列 故障诊断 改进麻雀搜索算法 随机森林算法
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基于QRFS的误差修正趋近律PMSM动态抗扰滑模控制
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作者 易才华 马家庆 +2 位作者 陈昌盛 何志琴 吴钦木 《组合机床与自动化加工技术》 北大核心 2026年第1期113-119,共7页
为了提升永磁同步电机(PMSM)矢量控制系统的动态响应性能,提出一种基于准随机分形搜索优化算法(QRFS)与误差修正双幂次趋近律协同设计的滑模控制策略。首先,采用一种基于误差修正双幂次趋近律(EDPRL)的速度滑模控制器,以提升电机控制系... 为了提升永磁同步电机(PMSM)矢量控制系统的动态响应性能,提出一种基于准随机分形搜索优化算法(QRFS)与误差修正双幂次趋近律协同设计的滑模控制策略。首先,采用一种基于误差修正双幂次趋近律(EDPRL)的速度滑模控制器,以提升电机控制系统的精度和稳定性;其次,用人类进化优化算法(HEOA)和角蜥优化算法(HLOA)分别优化速度滑模控制器的参数,进行对比分析;最后,利用准随机分形搜索优化算法对速度滑模控制器中的参数进行优化,获得最优参数值,并进行仿真。仿真和实验结果表明,与HEOA-EDPRL和HLOA-EDPRL策略相比,QRFS-EDPRL控制策略在系统响应速度和抗干扰能力方面表现更为优越,超调量从9.2%降至0.6%、动态响应时间缩短了81.5%、负载转矩变化下的转速降低幅度减少了28.2%。验证了所提出的QRFS-EDPRL控制方法的合理性和有效性。 展开更多
关键词 永磁同步电机 速度滑模控制 调速优化策略 准随机分形搜索优化算法
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双深度多层穿梭车仓储系统倒货策略与作业调度方法
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作者 周丰旭 刘飞 范国良 《机电工程》 北大核心 2026年第2期370-381,共12页
双深度多层穿梭车仓储系统普遍存在倒货作业,导致出入库作业时间增加,系统作业效率降低。随着货位占用率的上升,倒货作业调度的难度和复杂度持续增加。针对这一问题,提出了一种双深度多层穿梭车仓储系统倒货策略与作业调度方法。首先,... 双深度多层穿梭车仓储系统普遍存在倒货作业,导致出入库作业时间增加,系统作业效率降低。随着货位占用率的上升,倒货作业调度的难度和复杂度持续增加。针对这一问题,提出了一种双深度多层穿梭车仓储系统倒货策略与作业调度方法。首先,分析了倒货作业过程,提出了随机点倒货策略、最近点倒货策略和固定点倒货策略三种倒货作业策略,建立了倒货作业时间模型和任务调度出库作业时间模型;然后,以出库作业时间最小为目标,建立了出库作业调度优化模型;接着,设计了双种群遗传算法对模型进行了求解,引入了变邻域搜索及双种群重组和协作优化策略,增加了算法寻优能力,提升了算法搜索性能;最后,采用案例分析了倒货策略和作业调度方法的有效性,开展了算法对比分析以验证算法的优越性。研究结果表明:调度任务规模从35提高到100时,算法优化效率从13.28%提升到24.26%,双种群遗传算法的优化效率更高,能够有效缩短出库作业时间。集成倒货策略的调度优化方法能够准确评估倒货作业时间,进而提升双深度多层穿梭车仓储系统作业效率。 展开更多
关键词 双深度多层穿梭车仓储系统 倒货作业 变邻域搜索 遗传算法 随机点倒货策略 最近点倒货策略 固定点倒货策略
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基于CSSOA-DSRF模型的致密砂岩储层流体测井智能识别
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作者 展硕硕 李可赛 +5 位作者 刘岩 林行杰 雷铠铖 郑明明 刘彦君 冯国栋 《测井技术》 2026年第1期108-120,共13页
储层流体识别对致密砂岩油气藏评价和开发具有重要意义。致密砂岩储层具有低孔隙度低渗透率、非均质性强等特点,导致气水关系复杂。传统的储层流体识别方法主要依赖电阻率测井等数据,对于导电性对比度不强的储层流体识别困难。随着机器... 储层流体识别对致密砂岩油气藏评价和开发具有重要意义。致密砂岩储层具有低孔隙度低渗透率、非均质性强等特点,导致气水关系复杂。传统的储层流体识别方法主要依赖电阻率测井等数据,对于导电性对比度不强的储层流体识别困难。随着机器学习、人工智能技术的发展,测井技术与智能算法耦合在流体识别中发挥了关键性的作用。然而传统机器学习模型对重复度高、类间不平衡的样本缺乏区分能力,预测能力受限。提出一种基于混沌麻雀搜索算法-双重代价敏感随机森林(Chaos Sparrow Search Optimization Algorithm-Double Cost Sensitive Random Forest,CSSOA-DSRF)模型的致密砂岩储层流体测井智能识别方法。双重代价敏感随机森林(Double Cost Sensitive Random Forest,DSRF)在随机森林算法的特征选择阶段和集成投票阶段引入代价敏感学习,通过为不同流体类型分配权重系数,增强了模型对少数类样本的关注,使得特征选择更有针对性,从而选出对少数类数据更敏感的决策树集合,解决了样本类别不平衡问题。为克服传统优化方法易陷入局部最优的局限,混沌麻雀搜索算法(Chaos Sparrow Search Optimization Algorithm,CSSOA)在麻雀搜索算法(Sparrow Search Algorithm,SSA)的框架上融入改进的Tent混沌映射与高斯变异机制,提升了种群多样性与全局搜索能力,降低早收敛风险。该模型结合研究区声波时差测井、补偿中子测井、密度测井、自然伽马测井、深侧向电阻率测井这5条测井响应特征曲线输入和输出对应的流体类型预测结果。通过对照射孔结论预测准确率达到90.46%,并与DSRF、随机森林(Random Forest,RF)、K近邻算法(K-Nearest Neighbors,KNN)和支持向量机(Support Vector Machine,SVM)进行对比,该方法准确率高,保持了较好的鲁棒性和稳定性,可为致密砂岩储层流体识别提供一种可行方案。 展开更多
关键词 致密砂岩 机器学习 随机森林 支持向量机 麻雀搜索算法 遗传算法 决策树 种群
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Detection of micro-water in transformer oil based on ultrasonic pulse-echo method and sparrow search algorithm-random forest
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作者 Ziwen Huang Lufen Jia +2 位作者 Wenwen Gu Weigen Chen Qu Zhou 《High Voltage》 2025年第4期917-929,共13页
This study proposes a novel transformer oil micro-water detection method based on the ultrasonic pulse-echo technique,optimised by a sparrow search algorithm(SSA)to enhance the prediction performance of a random fores... This study proposes a novel transformer oil micro-water detection method based on the ultrasonic pulse-echo technique,optimised by a sparrow search algorithm(SSA)to enhance the prediction performance of a random forest(RF)model.Initially,finite element simulations were conducted to select optimal ultrasonic frequencies of 2 and 2.5 MHz.An accelerated thermal ageing experiment was performed using#25 Karamay oil samples,and ultrasonic pulse-echo signals were collected via a custom-built detection platform.Variational mode decomposition was employed to extract effective echoes from the raw pulse-echo signals.Temporal and frequency domain analyses yielded 162 dimensional features,which were subsequently filtered to 88 key parameters using the maximum information coefficient method.A transformer oil micro-water detection model was then developed by integrating the SSA with RF and trained using K-fold cross-validation.The model achieved an impressive average prediction accuracy of 97.34%over 10 cross-validation runs.The testing set demonstrated a prediction accuracy of 96.40%,a remarkable improvement of 16.53%compared to the unoptimised RF model.The findings provide a solid foundation for the rapid detection of micro-water content in transformer oil using the ultrasonic pulse-echo method. 展开更多
关键词 element simulations ultrasonic pulse echo Sparrow search algorithm random Forest enhance prediction performance Micro water detection Transformer oil sparrow search algorithm ssa
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Distribution System Optimization Planning Based on Plant Growth Simulation Algorithm 被引量:7
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作者 王淳 程浩忠 +1 位作者 胡泽春 王一 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第4期462-467,共6页
An approach for the integrated optimization of the construction/expansion capacity of high-voltage/ medium-voltage (HV/MV) substations and the configuration of MV radial distribution network was presented using plant ... An approach for the integrated optimization of the construction/expansion capacity of high-voltage/ medium-voltage (HV/MV) substations and the configuration of MV radial distribution network was presented using plant growth simulation algorithm (PGSA). In the optimization process, fixed costs correspondent to the investment in lines and substations and the variable costs associated to the operation of the system were considered under the constraints of branch capacity, substation capacity and bus voltage. The optimization variables considerably reduce the dimension of variables and speed up the process of optimizing. The effectiveness of the proposed approach was tested by a distribution system planning. 展开更多
关键词 distribution system planning plant growth simulation algorithm (PGSA) random search OPTIMIZATION
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ANew Theoretical Framework forAnalyzing Stochastic Global Optimization Algorithms 被引量:1
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作者 SHI Ding hua PENG Jian ping (College of Sciences, Shanghai University) 《Advances in Manufacturing》 SCIE CAS 1999年第3期175-180,共6页
In this paper, we develop a new theoretical framework by means of the absorbing Markov process theory for analyzing some stochastic global optimization algorithms. Applying the framework to the pure random search, we ... In this paper, we develop a new theoretical framework by means of the absorbing Markov process theory for analyzing some stochastic global optimization algorithms. Applying the framework to the pure random search, we prove that the pure random search converges to the global minimum in probability and its time has geometry distribution. We also analyze the pure adaptive search by this framework and turn out that the pure adaptive search converges to the global minimum in probability and its time has Poisson distribution. 展开更多
关键词 Global optimization stochastic global optimization algorithm random search absorbing Markov process
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Intelligent Iterated Local Search Methods for Solving Vehicle Routing Problem with Different Fleets
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作者 李妍峰 李军 赵达 《Journal of Southwest Jiaotong University(English Edition)》 2007年第4期344-352,共9页
To solve vehicle routing problem with different fleets, two methodologies are developed. The first methodology adopts twophase strategy. In the first phase, the improved savings method is used to assign customers to a... To solve vehicle routing problem with different fleets, two methodologies are developed. The first methodology adopts twophase strategy. In the first phase, the improved savings method is used to assign customers to appropriate vehicles. In the second phase, the iterated dynasearch algorithm is adopted to route each selected vehicle with the assigned customers. The iterated dynasearch algorithm combines dynasearch algorithm with iterated local search algorithm based on random kicks. The second methodplogy adopts the idea of cyclic transfer which is performed by using dynamic programming algorithm, and the iterated dynasearch algorithm is also embedded in it. The test results show that both methodologies generate better solutions than the traditional method, and the second methodology is superior to the first one. 展开更多
关键词 Vehicle routing problem Savings method Iterated dynasearch algorithm Dynamic programming Iterated local search random kick Cyclic transfer
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