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A Shared Natural Neighbors Based-Hierarchical Clustering Algorithm for Discovering Arbitrary-Shaped Clusters
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作者 Zhongshang Chen Ji Feng +1 位作者 Fapeng Cai Degang Yang 《Computers, Materials & Continua》 SCIE EI 2024年第8期2031-2048,共18页
In clustering algorithms,the selection of neighbors significantly affects the quality of the final clustering results.While various neighbor relationships exist,such as K-nearest neighbors,natural neighbors,and shared... In clustering algorithms,the selection of neighbors significantly affects the quality of the final clustering results.While various neighbor relationships exist,such as K-nearest neighbors,natural neighbors,and shared neighbors,most neighbor relationships can only handle single structural relationships,and the identification accuracy is low for datasets with multiple structures.In life,people’s first instinct for complex things is to divide them into multiple parts to complete.Partitioning the dataset into more sub-graphs is a good idea approach to identifying complex structures.Taking inspiration from this,we propose a novel neighbor method:Shared Natural Neighbors(SNaN).To demonstrate the superiority of this neighbor method,we propose a shared natural neighbors-based hierarchical clustering algorithm for discovering arbitrary-shaped clusters(HC-SNaN).Our algorithm excels in identifying both spherical clusters and manifold clusters.Tested on synthetic datasets and real-world datasets,HC-SNaN demonstrates significant advantages over existing clustering algorithms,particularly when dealing with datasets containing arbitrary shapes. 展开更多
关键词 Cluster analysis shared natural neighbor hierarchical clustering
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A Multi-Token Sector Antenna Neighbor Discovery Protocol for Directional Ad Hoc Networks
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作者 Zhang Hang Li Bo +2 位作者 Yan Zhongjiang Yang Mao Li Xinru 《China Communications》 SCIE CSCD 2024年第7期149-168,共20页
In this paper,we propose a Multi-token Sector Antenna Neighbor Discovery(M-SAND)protocol to enhance the efficiency of neighbor discovery in asynchronous directional ad hoc networks.The central concept of our work invo... In this paper,we propose a Multi-token Sector Antenna Neighbor Discovery(M-SAND)protocol to enhance the efficiency of neighbor discovery in asynchronous directional ad hoc networks.The central concept of our work involves maintaining multiple tokens across the network.To prevent mutual interference among multi-token holders,we introduce the time and space non-interference theorems.Furthermore,we propose a master-slave strategy between tokens.When the master token holder(MTH)performs the neighbor discovery,it decides which 1-hop neighbor is the next MTH and which 2-hop neighbors can be the new slave token holders(STHs).Using this approach,the MTH and multiple STHs can simultaneously discover their neighbors without causing interference with each other.Building on this foundation,we provide a comprehensive procedure for the M-SAND protocol.We also conduct theoretical analyses on the maximum number of STHs and the lower bound of multi-token generation probability.Finally,simulation results demonstrate the time efficiency of the M-SAND protocol.When compared to the QSAND protocol,which uses only one token,the total neighbor discovery time is reduced by 28% when 6beams and 112 nodes are employed. 展开更多
关键词 multi-token neighbor discovery SAND protocol sector antenna ad hoc network
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The GSI and Building a Neighborhood Community with a Shared Future
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作者 Luo Shengrong 《Contemporary World》 2024年第4期39-43,共5页
Against the backdrop of the international political and economic configuration featuring that“the East is rising and the West is declining”,relations between China and its neighboring countries enjoy steady developm... Against the backdrop of the international political and economic configuration featuring that“the East is rising and the West is declining”,relations between China and its neighboring countries enjoy steady development in general.However,the return of the Cold War mentality,rampant protectionism and prominent security governance issues have seriously threatened peace and stability in China’s neighboring region. 展开更多
关键词 PEACE neighboring neighborHOOD
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Probability Distribution of Arithmetic Average of China Aviation Network Edge Vertices Nearest Neighbor Average Degree Value and Its Evolutionary Trace Based on Complex Network
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作者 Cheng Xiangjun Yang Fang Xiong Zhihua 《Journal of Traffic and Transportation Engineering》 2024年第4期163-174,共12页
In order to reveal the complex network characteristics and evolution principle of China aviation network,the probability distribution and evolution trace of arithmetic average of edge vertices nearest neighbor average... In order to reveal the complex network characteristics and evolution principle of China aviation network,the probability distribution and evolution trace of arithmetic average of edge vertices nearest neighbor average degree values of China aviation network were studied based on the statistics data of China civil aviation network in 1988,1994,2001,2008 and 2015.According to the theory and method of complex network,the network system was constructed with the city where the airport was located as the network node and the route between cities as the edge of the network.Based on the statistical data,the arithmetic averages of edge vertices nearest neighbor average degree values of China aviation network in 1988,1994,2001,2008 and 2015 were calculated.Using the probability statistical analysis method,it was found that the arithmetic average of edge vertices nearest neighbor average degree values had the probability distribution of normal function and the position parameters and scale parameters of the probability distribution had linear evolution trace. 展开更多
关键词 Complex network China aviation network arithmetic average of edge vertices nearest neighbor average degree value linear evolution trace
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基于沙地猫群优化–最小二乘支持向量机的动态NOx排放预测 被引量:3
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作者 金秀章 史德金 乔鹏 《中国电机工程学报》 EI CSCD 北大核心 2024年第1期182-190,I0015,共10页
针对火电机组频繁调峰导致机组燃烧状态不稳,进而导致锅炉出口NOx浓度波动范围大的问题,提出一种基于沙地猫群优化(sand cat sarm optimization,SCSO)的最小二乘支持向量机(leastsquaressupportvectormachine,LSSVM) NOx动态预测模型。... 针对火电机组频繁调峰导致机组燃烧状态不稳,进而导致锅炉出口NOx浓度波动范围大的问题,提出一种基于沙地猫群优化(sand cat sarm optimization,SCSO)的最小二乘支持向量机(leastsquaressupportvectormachine,LSSVM) NOx动态预测模型。首先利用k近邻互信息计算时间延迟的同时筛选辅助变量。然后,基于SCSO算法进行输入变量阶次的选择。使用包含辅助变量时间延迟和阶次的信息作为模型的输入,SCSO算法优化最小二乘支持向量机参数,建立动态NOx排放最小二乘支持向量机预测模型(SCSO-LSSVM动态软测量模型)。最后将模型与未加入迟延的LSSVM模型,加入迟延的LSSVM模型和粒子群优化算法(particle swarm optimization,PSO)优化最小二乘支持向量机参数的动态软测量模型进行对比验证。结果表明,相较于其他模型,该文建立SCSO-LSSVM动态软测量模型均方根误差、平均绝对误差、平均绝对误差最小,预测精度最高,而且在NOx浓度剧烈波动时也能够较好地预测NOx浓度,具有很好的动态特性。 展开更多
关键词 NOx浓度 k近邻互信息 沙地猫群优化算法 最小二乘支持向量机 软测量模型
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Active learning accelerated Monte-Carlo simulation based on the modified K-nearest neighbors algorithm and its application to reliability estimations
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作者 Zhifeng Xu Jiyin Cao +2 位作者 Gang Zhang Xuyong Chen Yushun Wu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第10期306-313,共8页
This paper proposes an active learning accelerated Monte-Carlo simulation method based on the modified K-nearest neighbors algorithm.The core idea of the proposed method is to judge whether or not the output of a rand... This paper proposes an active learning accelerated Monte-Carlo simulation method based on the modified K-nearest neighbors algorithm.The core idea of the proposed method is to judge whether or not the output of a random input point can be postulated through a classifier implemented through the modified K-nearest neighbors algorithm.Compared to other active learning methods resorting to experimental designs,the proposed method is characterized by employing Monte-Carlo simulation for sampling inputs and saving a large portion of the actual evaluations of outputs through an accurate classification,which is applicable for most structural reliability estimation problems.Moreover,the validity,efficiency,and accuracy of the proposed method are demonstrated numerically.In addition,the optimal value of K that maximizes the computational efficiency is studied.Finally,the proposed method is applied to the reliability estimation of the carbon fiber reinforced silicon carbide composite specimens subjected to random displacements,which further validates its practicability. 展开更多
关键词 Active learning Monte-carlo simulation K-nearest neighbors Reliability estimation CLASSIFICATION
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China’s Efforts to Build a Community with a Shared Future in the Neighborhood from the Perspective of Major-country Competition
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作者 Zhou Fangyin 《Contemporary World》 2023年第4期12-17,共6页
Since the 18th National Congress of the Communist Party of China,China has proposed and actively acted on the important vision of building a community with a shared future for mankind.In October 2013,President Xi Jinp... Since the 18th National Congress of the Communist Party of China,China has proposed and actively acted on the important vision of building a community with a shared future for mankind.In October 2013,President Xi Jinping put forward that“the building of a community with a shared future should be advanced in China’s neighboring countries”. 展开更多
关键词 neighborHOOD neighboring MAJOR
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CIIS Organizes International Symposium to Commemorate China’s Principle in Neighborhood Diplomacy
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《China International Studies》 2023年第5期F0003-F0003,共1页
On October 24,the International Symposium to Commemorate the10th Anniversary of China's Principle of Amity,Sincerity,Mutual Benefit and Inclusiveness in Neighborhood Diplomacy was held in Beijing.Co-hosted by the ... On October 24,the International Symposium to Commemorate the10th Anniversary of China's Principle of Amity,Sincerity,Mutual Benefit and Inclusiveness in Neighborhood Diplomacy was held in Beijing.Co-hosted by the Office of the Central Commission for Foreign Affairs and the Ministry of Foreign Affairs,and organized by China Institute of International Studies(CIIS),the Symposium was attended by more than200 representatives including political figures from neighboring countries,heads of international and regional organizations,diplomatic envoys of neighboring countries to China and renowned experts and scholars. 展开更多
关键词 neighborHOOD neighboring diplomatic
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A Pattern Classification Model for Vowel Data Using Fuzzy Nearest Neighbor
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作者 Monika Khandelwal Ranjeet Kumar Rout +4 位作者 Saiyed Umer Kshira Sagar Sahoo NZ Jhanjhi Mohammad Shorfuzzaman Mehedi Masud 《Intelligent Automation & Soft Computing》 SCIE 2023年第3期3587-3598,共12页
Classification of the patterns is a crucial structure of research and applications. Using fuzzy set theory, classifying the patterns has become of great interest because of its ability to understand the parameters. ... Classification of the patterns is a crucial structure of research and applications. Using fuzzy set theory, classifying the patterns has become of great interest because of its ability to understand the parameters. One of the problemsobserved in the fuzzification of an unknown pattern is that importance is givenonly to the known patterns but not to their features. In contrast, features of thepatterns play an essential role when their respective patterns overlap. In this paper,an optimal fuzzy nearest neighbor model has been introduced in which a fuzzifi-cation process has been carried out for the unknown pattern using k nearest neighbor. With the help of the fuzzification process, the membership matrix has beenformed. In this membership matrix, fuzzification has been carried out of the features of the unknown pattern. Classification results are verified on a completelyllabelled Telugu vowel data set, and the accuracy is compared with the differentmodels and the fuzzy k nearest neighbor algorithm. The proposed model gives84.86% accuracy on 50% training data set and 89.35% accuracy on 80% trainingdata set. The proposed classifier learns well enough with a small amount of training data, resulting in an efficient and faster approach. 展开更多
关键词 Nearest neighbors fuzzy classification patterns recognition reasoning rule membership matrix
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Real-Time Data Transmission with Data Carrier Support Value in Neighbor Strategic Collection in WSN
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作者 S.Ponnarasi T.Rajendran 《Computers, Materials & Continua》 SCIE EI 2023年第6期6039-6057,共19页
An efficient trust-aware secure routing and network strategy-based data collection scheme is presented in this paper to enhance the performance and security of wireless sensor networks during data collection.The metho... An efficient trust-aware secure routing and network strategy-based data collection scheme is presented in this paper to enhance the performance and security of wireless sensor networks during data collection.The method first discovers the routes between the data sensors and the sink node.Several factors are considered for each sensor node along the route,including energy,number of neighbours,previous transmissions,and energy depletion ratio.Considering all these variables,the Sink Reachable Support Measure and the Secure Communication Support Measure,the method evaluates two distinct measures.The method calculates the data carrier support value using these two metrics.A single route is chosen to collect data based on the value of data carrier support.It has contributed to the design of Secure Communication Support(SCS)Estimation.This has been measured according to the strategy of each hop of the route.The suggested method improves the security and efficacy of data collection in wireless sensor networks.The second stage uses the two-fish approach to build a trust model for secure data transfer.A sim-ulation exercise was conducted to evaluate the effectiveness of the suggested framework.Metrics,including PDR,end-to-end latency,and average residual energy,were assessed for the proposed model.The efficiency of the suggested route design serves as evidence for the average residual energy for the proposed framework. 展开更多
关键词 Data carrier support data collection neighbor strategy secure routing wireless sensor network
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The g-Good-Neighbor Connectivity of Some Cartesian Product Graphs 被引量:1
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作者 Yinkui Li Ting Xie Xiaoxiao Qin 《Open Journal of Discrete Mathematics》 2023年第1期27-37,共11页
The g-good-neighbor connectivity of G is a generalization of the concept of connectivity, which is just for, and an important parameter in measuring the fault tolerance and reliability of interconnection network. Many... The g-good-neighbor connectivity of G is a generalization of the concept of connectivity, which is just for, and an important parameter in measuring the fault tolerance and reliability of interconnection network. Many well-known networks can be constructed by the Cartesian products of some simple graphs. In this paper, we determine the g-good-neighbor connectivity of some Cartesian product graphs. We give the exact value of g-good-neighbor connectivity of the Cartesian product of two complete graphs and for , mesh for , cylindrical grid and torus for . 展开更多
关键词 CONNECTIVITY The g-Good-neighbor Connectivity Cartesian Product
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GHM-FKNN:a generalized Heronian mean based fuzzy k-nearest neighbor classifier for the stock trend prediction
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作者 吴振峰 WANG Mengmeng +1 位作者 LAN Tian ZHANG Anyuan 《High Technology Letters》 EI CAS 2023年第2期122-129,共8页
Stock trend prediction is a challenging problem because it involves many variables.Aiming at the problem that some existing machine learning techniques, such as random forest(RF), probabilistic random forest(PRF), k-n... Stock trend prediction is a challenging problem because it involves many variables.Aiming at the problem that some existing machine learning techniques, such as random forest(RF), probabilistic random forest(PRF), k-nearest neighbor(KNN), and fuzzy KNN(FKNN), have difficulty in accurately predicting the stock trend(uptrend or downtrend) for a given date, a generalized Heronian mean(GHM) based FKNN predictor named GHM-FKNN was proposed.GHM-FKNN combines GHM aggregation function with the ideas of the classical FKNN approach.After evaluation, the comparison results elucidated that GHM-FKNN outperformed the other best existing methods RF, PRF, KNN and FKNN on independent test datasets corresponding to three stocks, namely AAPL, AMZN and NFLX.Compared with RF, PRF, KNN and FKNN, GHM-FKNN achieved the best performance with accuracy of 62.37% for AAPL, 58.25% for AMZN, and 64.10% for NFLX. 展开更多
关键词 stock trend prediction Heronian mean fuzzy k-nearest neighbor(FKNN)
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Diagnosis of Disc Space Variation Fault Degree of Transformer Winding Based on K-Nearest Neighbor Algorithm
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作者 Song Wang Fei Xie +3 位作者 Fengye Yang Shengxuan Qiu Chuang Liu Tong Li 《Energy Engineering》 EI 2023年第10期2273-2285,共13页
Winding is one of themost important components in power transformers.Ensuring the health state of the winding is of great importance to the stable operation of the power system.To efficiently and accurately diagnose t... Winding is one of themost important components in power transformers.Ensuring the health state of the winding is of great importance to the stable operation of the power system.To efficiently and accurately diagnose the disc space variation(DSV)fault degree of transformer winding,this paper presents a diagnostic method of winding fault based on the K-Nearest Neighbor(KNN)algorithmand the frequency response analysis(FRA)method.First,a laboratory winding model is used,and DSV faults with four different degrees are achieved by changing disc space of the discs in the winding.Then,a series of FRA tests are conducted to obtain the FRA results and set up the FRA dataset.Second,ten different numerical indices are utilized to obtain features of FRA curves of faulted winding.Third,the 10-fold cross-validation method is employed to determine the optimal k-value of KNN.In addition,to improve the accuracy of the KNN model,a comparative analysis is made between the accuracy of the KNN algorithm and k-value under four distance functions.After getting the most appropriate distance metric and kvalue,the fault classificationmodel based on theKNN and FRA is constructed and it is used to classify the degrees of DSV faults.The identification accuracy rate of the proposed model is up to 98.30%.Finally,the performance of the model is presented by comparing with the support vector machine(SVM),SVM optimized by the particle swarmoptimization(PSO-SVM)method,and randomforest(RF).The results show that the diagnosis accuracy of the proposed model is the highest and the model can be used to accurately diagnose the DSV fault degrees of the winding. 展开更多
关键词 Transformer winding frequency response analysis(FRA)method K-Nearest neighbor(KNN) disc space variation(DSV)
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Probability Distribution of China Aviation Network Nearest Neighbor Average Degree and Its Evolutionary Trace Based on Complex Network
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作者 Cheng Xiangjun Zhang Chunyue Guo Jianyuan 《Journal of Traffic and Transportation Engineering》 2023年第3期95-106,共12页
In order to reveal the complex network characteristics and evolution principle of China aviation network,the probability distribution and evolution trace of node nearest neighbor average degree of China aviation netwo... In order to reveal the complex network characteristics and evolution principle of China aviation network,the probability distribution and evolution trace of node nearest neighbor average degree of China aviation network were studied based on the statistics data of China civil aviation network in 1988,1994,2001,2008 and 2015.According to the theory and method of complex network,the network system was constructed with the city where the airport was located as the network node and the route between cities as the edge of the network.Based on the statistical data,the nearest neighbor average degrees of nodes in China aviation network in 1988,1994,2001,2008 and 2015 were calculated.Using the probability statistical analysis method,it was found that the nearest neighbor average degree had the probability distribution of normal function and the position parameters and scale parameters of the probability distribution had linear evolution trace. 展开更多
关键词 Complex network China aviation network nearest neighbor average degree normal probability distribution linear evolution trace
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Nonlinear Relationship and Its Evolutionary Trace between Node Degree and Nearest Neighbor Average Degree of China Aviation Network Based on Complex Network
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作者 Cheng Xiangjun Zhang Chunyue Zhang Xiaoxuan 《Journal of Traffic and Transportation Engineering》 2023年第4期159-171,共13页
In order to reveal the complex network characteristics and evolution principle of China aviation network, the relationship between the node degree and the nearest neighbor average degree and its evolution trace of Chi... In order to reveal the complex network characteristics and evolution principle of China aviation network, the relationship between the node degree and the nearest neighbor average degree and its evolution trace of China aviation network in 1988, 1994, 2001, 2008 and 2015 were studied. According to the theory and method of complex network, the network system was constructed with the city where the airport was located as the network node and the airline as the edge of the network. According to the statistical data, the node nearest neighbor average degree of China aviation network in 1988, 1994, 2001, 2008 and 2015 was calculated. Through regression analysis, it was found that the node degree had a negative exponential relationship with the nearest neighbor average degree, and the two parameters of the negative exponential relationship had linear evolution trace. 展开更多
关键词 China aviation network complex network node degree nearest neighbor average degree negative exponential relationship evolution trace.
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基于网格近邻优化的密度峰值聚类算法 被引量:1
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作者 刘继 杨金瑞 《计算机应用研究》 CSCD 北大核心 2024年第4期1058-1063,共6页
密度峰值聚类(DPC)将数据样本点的局部密度和相对距离进行结合,能对任意形状数据集进行聚类处理,但密度峰值聚类算法存在主观选择截断距离、简单分配策略和较高时间复杂度等问题。为此,提出了一种基于网格近邻优化的密度峰值聚类算法(KG... 密度峰值聚类(DPC)将数据样本点的局部密度和相对距离进行结合,能对任意形状数据集进行聚类处理,但密度峰值聚类算法存在主观选择截断距离、简单分配策略和较高时间复杂度等问题。为此,提出了一种基于网格近邻优化的密度峰值聚类算法(KG-DPC算法)。首先对数据空间进行网格化,减少了样本数据点之间距离的计算量;在计算局部密度时不仅考虑了网格自身的密度值,而且考虑了周围k个近邻的网格密度值,降低了主观选择截断距离对聚类结果的影响,提高了聚类准确率,设定网格密度阈值,保证了聚类结果的稳定性。通过实验结果表明,KG-DPC算法比DBSCAN、DPC和SDPC算法在聚类准确率上有很大提升,在聚类平均消耗时间上DPC、SNN-DPC和DPC-NN算法分别降低38%、44%和44%。在保证基本聚类准确率的基础上,KG-DPC算法在聚类效率上有特定优势。 展开更多
关键词 密度峰值聚类 密度阈值 网格 近邻优化
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基于时域波形特征认知的输电线路近端故障辨识与定位 被引量:1
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作者 张广斌 陈柏宇 +1 位作者 束洪春 司大军 《电力系统自动化》 EI CSCD 北大核心 2024年第5期146-156,共11页
针对现有单端行波故障测距对近端故障存在测距盲区、双端行波故障测距对近端故障测距误差较大,无法满足工程需要的不足,提出基于波形特征认知的近端故障辨识与定位方法。首先,分析了线路故障行波传播规律,以固定分辨率显示波形。发现线... 针对现有单端行波故障测距对近端故障存在测距盲区、双端行波故障测距对近端故障测距误差较大,无法满足工程需要的不足,提出基于波形特征认知的近端故障辨识与定位方法。首先,分析了线路故障行波传播规律,以固定分辨率显示波形。发现线路近端故障时,初始行波及其后续波形在长时窗整体宏观观测下呈堆叠缓变特征,而在短时窗局部放大观测下呈周期性变化特征,且周期与故障距离相关。不同线路的近端故障历史样本能统一作为参照基准为测距提供提示。进而提出基于波形密度和突变分布的近端故障辨识方法。最后,对辨识出的近端故障进行周期估计,利用近端故障与线长的无关性以及历史样本突变周期和故障位置已知性,搜索周期最近邻历史样本,并由已知故障距离插值实现故障位置确定。基于大量实测数据进行仿真测试,结果表明所提方法能够显著提升单端行波测距可靠性和成功率。 展开更多
关键词 故障测距 近端故障 行波 突变周期 近邻搜索 像素密度分布
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面向栅格地图的区域渐进均分算法
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作者 姚寿文 郝青华 +2 位作者 许人介 王晓宇 李波 《兵器装备工程学报》 CAS CSCD 北大核心 2024年第6期166-174,共9页
单架无人机续航能力限制了区域全覆盖侦察,合理的区域划分是实现多无人机协同全域侦察的关键。栅格法规划侦察区域是无人机区域侦察的常用研究方法。为了解决栅格地图等量划分的问题,提出了一种面向栅格地图的区域渐进均分算法。算法由... 单架无人机续航能力限制了区域全覆盖侦察,合理的区域划分是实现多无人机协同全域侦察的关键。栅格法规划侦察区域是无人机区域侦察的常用研究方法。为了解决栅格地图等量划分的问题,提出了一种面向栅格地图的区域渐进均分算法。算法由4个阶段构成。阶段1,建立区域边界确认的跳跃迭代法,根据栅格的特点制定判定条件,进行栅格特征标识。阶段2,提出一种双特征标识方法,对射线法进行改进,确定区域内部栅格。阶段3,模仿水波扩散,提出了一种邻边扩散法,实现区域初步的扩散分割。阶段4,设计补偿规则,通过邻边补偿算法,对各子区域栅格数进行数量补偿。实验证明,区域渐进均分算法相较于其他算法,具有较好的聚集性,连续性和均匀性,为多无人机协同全域侦察提供了理论保证。 展开更多
关键词 渐进均分算法 跳跃迭代 射线法 邻边扩散 邻边补偿
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面向密度分布不均数据的加权逆近邻密度峰值聚类算法
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作者 吕莉 陈威 +2 位作者 肖人彬 韩龙哲 谭德坤 《智能系统学报》 CSCD 北大核心 2024年第1期165-175,共11页
针对密度分布不均数据,密度峰值聚类算法易忽略类簇间样本的疏密差异,导致误选类簇中心;分配策略易将稀疏区域的样本误分到密集区域,导致聚类效果不佳的问题,本文提出一种面向密度分布不均数据的加权逆近邻密度峰值聚类算法。该算法首... 针对密度分布不均数据,密度峰值聚类算法易忽略类簇间样本的疏密差异,导致误选类簇中心;分配策略易将稀疏区域的样本误分到密集区域,导致聚类效果不佳的问题,本文提出一种面向密度分布不均数据的加权逆近邻密度峰值聚类算法。该算法首先在局部密度公式中引入基于sigmoid函数的权重系数,增加稀疏区域样本的权重,结合逆近邻思想,重新定义了样本的局部密度,有效提升类簇中心的识别率;其次,引入改进的样本相似度策略,利用样本间的逆近邻及共享逆近邻信息,使得同一类簇样本间具有较高的相似度,可有效改善稀疏区域样本分配错误的问题。在密度分布不均、复杂形态和UCI数据集上的对比实验表明,本文算法的聚类效果优于IDPC-FA、FNDPC、FKNN-DPC、DPC和DPCSA算法。 展开更多
关键词 密度峰值聚类 密度分布不均 逆近邻 共享逆近邻 样本相似度 局部密度 分配策略 数据挖掘
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融合CNN和ViT的声信号轴承故障诊断方法 被引量:2
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作者 宁方立 王珂 郝明阳 《振动与冲击》 EI CSCD 北大核心 2024年第3期158-163,170,共7页
针对轴承故障诊断任务数据量少、故障信号非平稳等特点,提出一种短时傅里叶变换、卷积神经网络和视觉转换器相结合的轴承故障诊断方法。首先,利用短时傅里叶变换将原始声信号转换为包含时序信息和频率信息的时频图像。其次,将时频图像... 针对轴承故障诊断任务数据量少、故障信号非平稳等特点,提出一种短时傅里叶变换、卷积神经网络和视觉转换器相结合的轴承故障诊断方法。首先,利用短时傅里叶变换将原始声信号转换为包含时序信息和频率信息的时频图像。其次,将时频图像作为卷积神经网络的输入,用于隐式提取图像的深层特征,其输出作为视觉转换器的输入。视觉转换器用于提取信号的时间序列信息。并在输出层利用Softmax函数实现故障模式的识别。试验结果表明,该方法对于轴承故障诊断准确率较高。为了更好解释和优化提出的轴承故障诊断方法,利用t-分布领域嵌入算法对分类特征进行了可视化展示。 展开更多
关键词 短时傅里叶变换 卷积神经网络 视觉转换器 t-分布领域嵌入算法
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