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Multifactor diagnostic model of converter energy consumption based on K-means algorithm and its application
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作者 Fei-xiang Dai Guang Chen +3 位作者 Xiang-jun Bao Gong-guo Liu Lu Zhang Xiao-jing Yang 《Journal of Iron and Steel Research International》 2025年第8期2359-2369,共11页
To address the challenge of identifying the primary causes of energy consumption fluctuations and accurately assessing the influence of various factors in the converter unit of an iron and steel plant,the focus is pla... To address the challenge of identifying the primary causes of energy consumption fluctuations and accurately assessing the influence of various factors in the converter unit of an iron and steel plant,the focus is placed on the critical components of material and heat balance.Through a thorough analysis of the interactions between various components and energy consumptions,six pivotal factors have been identified—raw material composition,steel type,steel temperature,slag temperature,recycling practices,and operational parameters.Utilizing a framework based on an equivalent energy consumption model,an integrated intelligent diagnostic model has been developed that encapsulates these factors,providing a comprehensive assessment tool for converter energy consumption.Employing the K-means clustering algorithm,historical operational data from the converter have been meticulously analyzed to determine baseline values for essential variables such as energy consumption and recovery rates.Building upon this data-driven foundation,an innovative online system for the intelligent diagnosis of converter energy consumption has been crafted and implemented,enhancing the precision and efficiency of energy management.Upon implementation with energy consumption data at a steel plant in 2023,the diagnostic analysis performed by the system exposed significant variations in energy usage across different converter units.The analysis revealed that the most significant factor influencing the variation in energy consumption for both furnaces was the steel grade,with contributions of−0.550 and 0.379. 展开更多
关键词 Equivalent energy consumption model Intelligent diagnostic model k-means clustering algorithm Online system Energy management
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Coordinate Descent K-means Algorithm Based on Split-Merge
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作者 Fuheng Qu Yuhang Shi +2 位作者 Yong Yang Yating Hu Yuyao Liu 《Computers, Materials & Continua》 SCIE EI 2024年第12期4875-4893,共19页
The Coordinate Descent Method for K-means(CDKM)is an improved algorithm of K-means.It identifies better locally optimal solutions than the original K-means algorithm.That is,it achieves solutions that yield smaller ob... The Coordinate Descent Method for K-means(CDKM)is an improved algorithm of K-means.It identifies better locally optimal solutions than the original K-means algorithm.That is,it achieves solutions that yield smaller objective function values than the K-means algorithm.However,CDKM is sensitive to initialization,which makes the K-means objective function values not small enough.Since selecting suitable initial centers is not always possible,this paper proposes a novel algorithm by modifying the process of CDKM.The proposed algorithm first obtains the partition matrix by CDKM and then optimizes the partition matrix by designing the split-merge criterion to reduce the objective function value further.The split-merge criterion can minimize the objective function value as much as possible while ensuring that the number of clusters remains unchanged.The algorithm avoids the distance calculation in the traditional K-means algorithm because all the operations are completed only using the partition matrix.Experiments on ten UCI datasets show that the solution accuracy of the proposed algorithm,measured by the E value,is improved by 11.29%compared with CDKM and retains its efficiency advantage for the high dimensional datasets.The proposed algorithm can find a better locally optimal solution in comparison to other tested K-means improved algorithms in less run time. 展开更多
关键词 Cluster analysis k-means coordinate descent k-means SPLIT-MERGE
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Estimating wheat fractional vegetation cover using a density peak k-means algorithm based on hyperspectral image data 被引量:6
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作者 LIU Da-zhong YANG Fei-fei LIU Sheng-ping 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第11期2880-2891,共12页
Fractional vegetation cover(FVC)is an important parameter to measure crop growth.In studies of crop growth monitoring,it is very important to extract FVC quickly and accurately.As the most widely used FVC extraction m... Fractional vegetation cover(FVC)is an important parameter to measure crop growth.In studies of crop growth monitoring,it is very important to extract FVC quickly and accurately.As the most widely used FVC extraction method,the photographic method has the advantages of simple operation and high extraction accuracy.However,when soil moisture and acquisition times vary,the extraction results are less accurate.To accommodate various conditions of FVC extraction,this study proposes a new FVC extraction method that extracts FVC from a normalized difference vegetation index(NDVI)greyscale image of wheat by using a density peak k-means(DPK-means)algorithm.In this study,Yangfumai 4(YF4)planted in pots and Yangmai 16(Y16)planted in the field were used as the research materials.With a hyperspectral imaging camera mounted on a tripod,ground hyperspectral images of winter wheat under different soil conditions(dry and wet)were collected at 1 m above the potted wheat canopy.Unmanned aerial vehicle(UAV)hyperspectral images of winter wheat at various stages were collected at 50 m above the field wheat canopy by a UAV equipped with a hyperspectral camera.The pixel dichotomy method and DPK-means algorithm were used to classify vegetation pixels and non-vegetation pixels in NDVI greyscale images of wheat,and the extraction effects of the two methods were compared and analysed.The results showed that extraction by pixel dichotomy was influenced by the acquisition conditions and its error distribution was relatively scattered,while the extraction effect of the DPK-means algorithm was less affected by the acquisition conditions and its error distribution was concentrated.The absolute values of error were 0.042 and 0.044,the root mean square errors(RMSE)were 0.028 and 0.030,and the fitting accuracy R2 of the FVC was 0.87 and 0.93,under dry and wet soil conditions and under various time conditions,respectively.This study found that the DPK-means algorithm was capable of achieving more accurate results than the pixel dichotomy method in various soil and time conditions and was an accurate and robust method for FVC extraction. 展开更多
关键词 fractional vegetation cover k-means algorithm NDVI vegetation index WHEAT
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A Hybrid Method Combining Improved K-means Algorithm with BADA Model for Generating Nominal Flight Profiles 被引量:1
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作者 Tang Xinmin Gu Junwei +2 位作者 Shen Zhiyuan Chen Ping Li Bo 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2016年第4期414-424,共11页
A high-precision nominal flight profile,involving controllers′intentions is critical for 4Dtrajectory estimation in modern automatic air traffic control systems.We proposed a novel method to effectively improve the a... A high-precision nominal flight profile,involving controllers′intentions is critical for 4Dtrajectory estimation in modern automatic air traffic control systems.We proposed a novel method to effectively improve the accuracy of the nominal flight profile,including the nominal altitude profile and the speed profile.First,considering the characteristics of trajectory data,we developed an improved K-means algorithm.The approach was to measure the similarity between different altitude profiles by integrating the space warp edit distance algorithm,thereby to acquire several fitted nominal flight altitude profiles.This approach breaks the constraints of traditional K-means algorithms.Second,to eliminate the influence of meteorological factors,we introduced historical gridded binary data to determine the en-route wind speed and temperature via inverse distance weighted interpolation.Finally,we facilitated the true airspeed determined by speed triangle relationships and the calibrated airspeed determined by aircraft data model to extract a more accurate nominal speed profile from each cluster,therefore we could describe the airspeed profiles above and below the airspeed transition altitude,respectively.Our experimental results showed that the proposed method could obtain a highly accurate nominal flight profile,which reflects the actual aircraft flight status. 展开更多
关键词 air transportation flight profile k-means algorithm space warp edit distance(SWED)algorithm trajectory prediction
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Similarity matrix-based K-means algorithm for text clustering
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作者 曹奇敏 郭巧 吴向华 《Journal of Beijing Institute of Technology》 EI CAS 2015年第4期566-572,共7页
K-means algorithm is one of the most widely used algorithms in the clustering analysis. To deal with the problem caused by the random selection of initial center points in the traditional al- gorithm, this paper propo... K-means algorithm is one of the most widely used algorithms in the clustering analysis. To deal with the problem caused by the random selection of initial center points in the traditional al- gorithm, this paper proposes an improved K-means algorithm based on the similarity matrix. The im- proved algorithm can effectively avoid the random selection of initial center points, therefore it can provide effective initial points for clustering process, and reduce the fluctuation of clustering results which are resulted from initial points selections, thus a better clustering quality can be obtained. The experimental results also show that the F-measure of the improved K-means algorithm has been greatly improved and the clustering results are more stable. 展开更多
关键词 text clustering k-means algorithm similarity matrix F-MEASURE
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An Improved K-Means Algorithm Based on Initial Clustering Center Optimization
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作者 LI Taihao NAREN Tuya +2 位作者 ZHOU Jianshe REN Fuji LIU Shupeng 《ZTE Communications》 2017年第B12期43-46,共4页
The K-means algorithm is widely known for its simplicity and fastness in text clustering.However,the selection of the initial clus?tering center with the traditional K-means algorithm is some random,and therefore,the ... The K-means algorithm is widely known for its simplicity and fastness in text clustering.However,the selection of the initial clus?tering center with the traditional K-means algorithm is some random,and therefore,the fluctuations and instability of the clustering results are strongly affected by the initial clustering center.This paper proposed an algorithm to select the initial clustering center to eliminate the uncertainty of central point selection.The experiment results show that the improved K-means clustering algorithm is superior to the traditional algorithm. 展开更多
关键词 CLUSTERING k-means algorithm initial clustering center
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Polarimetric Meteorological Satellite Data Processing Software Classification Based on Principal Component Analysis and Improved K-Means Algorithm 被引量:1
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作者 Manyun Lin Xiangang Zhao +3 位作者 Cunqun Fan Lizi Xie Lan Wei Peng Guo 《Journal of Geoscience and Environment Protection》 2017年第7期39-48,共10页
With the increasing variety of application software of meteorological satellite ground system, how to provide reasonable hardware resources and improve the efficiency of software is paid more and more attention. In th... With the increasing variety of application software of meteorological satellite ground system, how to provide reasonable hardware resources and improve the efficiency of software is paid more and more attention. In this paper, a set of software classification method based on software operating characteristics is proposed. The method uses software run-time resource consumption to describe the software running characteristics. Firstly, principal component analysis (PCA) is used to reduce the dimension of software running feature data and to interpret software characteristic information. Then the modified K-means algorithm was used to classify the meteorological data processing software. Finally, it combined with the results of principal component analysis to explain the significance of various types of integrated software operating characteristics. And it is used as the basis for optimizing the allocation of software hardware resources and improving the efficiency of software operation. 展开更多
关键词 Principal COMPONENT ANALYSIS Improved k-mean algorithm METEOROLOGICAL Data Processing FEATURE ANALYSIS SIMILARITY algorithm
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Dynamic grouping control of electric vehicles based on improved k-means algorithm for wind power fluctuations suppression 被引量:5
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作者 Yang Yu Mai Liu +2 位作者 Dongyang Chen Yuhang Huo Wentao Lu 《Global Energy Interconnection》 EI CSCD 2023年第5期542-553,共12页
To address the significant lifecycle degradation and inadequate state of charge(SOC)balance of electric vehicles(EVs)when mitigating wind power fluctuations,a dynamic grouping control strategy is proposed for EVs base... To address the significant lifecycle degradation and inadequate state of charge(SOC)balance of electric vehicles(EVs)when mitigating wind power fluctuations,a dynamic grouping control strategy is proposed for EVs based on an improved k-means algorithm.First,a swing door trending(SDT)algorithm based on compression result feedback was designed to extract the feature data points of wind power.The gating coefficient of the SDT was adjusted based on the compression ratio and deviation,enabling the acquisition of grid-connected wind power signals through linear interpolation.Second,a novel algorithm called IDOA-KM is proposed,which utilizes the Improved Dingo Optimization Algorithm(IDOA)to optimize the clustering centers of the k-means algorithm,aiming to address its dependence and sensitivity on the initial centers.The EVs were categorized into priority charging,standby,and priority discharging groups using the IDOA-KM.Finally,an two-layer power distribution scheme for EVs was devised.The upper layer determines the charging/discharging sequences of the three EV groups and their corresponding power signals.The lower layer allocates power signals to each EV based on the maximum charging/discharging power or SOC equalization principles.The simulation results demonstrate the effectiveness of the proposed control strategy in accurately tracking grid power signals,smoothing wind power fluctuations,mitigating EV degradation,and enhancing the SOC balance. 展开更多
关键词 Electric vehicles Wind power fluctuation smoothing Improved k-means Power allocation Swing door trending
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A Nonuniform Clustering Routing Algorithm Based on an Improved K-Means Algorithm 被引量:3
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作者 Xinliang Tang Man Zhang +3 位作者 Pingping Yu Wei Liu Ning Cao Yunfeng Xu 《Computers, Materials & Continua》 SCIE EI 2020年第9期1725-1739,共15页
In a large-scale wireless sensor network(WSN),densely distributed sensor nodes process a large amount of data.The aggregation of data in a network can consume a great amount of energy.To balance and reduce the energy ... In a large-scale wireless sensor network(WSN),densely distributed sensor nodes process a large amount of data.The aggregation of data in a network can consume a great amount of energy.To balance and reduce the energy consumption of nodes in a WSN and extend the network life,this paper proposes a nonuniform clustering routing algorithm based on the improved K-means algorithm.The algorithm uses a clustering method to form and optimize clusters,and it selects appropriate cluster heads to balance network energy consumption and extend the life cycle of the WSN.To ensure that the cluster head(CH)selection in the network is fair and that the location of the selected CH is not concentrated within a certain range,we chose the appropriate CH competition radius.Simulation results show that,compared with LEACH,LEACH-C,and the DEEC clustering algorithm,this algorithm can effectively balance the energy consumption of the CH and extend the network life. 展开更多
关键词 WSN node energy consumption nonuniform clustering routing algorithm
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SMK-means:An Improved Mini Batch K-means Algorithm Based on Mapreduce with Big Data 被引量:1
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作者 Bo Xiao Zhen Wang +1 位作者 Qi Liu Xiaodong Liu 《Computers, Materials & Continua》 SCIE EI 2018年第9期365-379,共15页
In recent years,the rapid development of big data technology has also been favored by more and more scholars.Massive data storage and calculation problems have also been solved.At the same time,outlier detection probl... In recent years,the rapid development of big data technology has also been favored by more and more scholars.Massive data storage and calculation problems have also been solved.At the same time,outlier detection problems in mass data have also come along with it.Therefore,more research work has been devoted to the problem of outlier detection in big data.However,the existing available methods have high computation time,the improved algorithm of outlier detection is presented,which has higher performance to detect outlier.In this paper,an improved algorithm is proposed.The SMK-means is a fusion algorithm which is achieved by Mini Batch K-means based on simulated annealing algorithm for anomalous detection of massive household electricity data,which can give the number of clusters and reduce the number of iterations and improve the accuracy of clustering.In this paper,several experiments are performed to compare and analyze multiple performances of the algorithm.Through analysis,we know that the proposed algorithm is superior to the existing algorithms. 展开更多
关键词 BIG data OUTLIER detection SMk-means MINI BATCH k-means simulated annealing
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Genetic Algorithm Combined with the K-Means Algorithm:A Hybrid Technique for Unsupervised Feature Selection
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作者 Hachemi Bennaceur Meznah Almutairy Norah Alhussain 《Intelligent Automation & Soft Computing》 SCIE 2023年第9期2687-2706,共20页
The dimensionality of data is increasing very rapidly,which creates challenges for most of the current mining and learning algorithms,such as large memory requirements and high computational costs.The literature inclu... The dimensionality of data is increasing very rapidly,which creates challenges for most of the current mining and learning algorithms,such as large memory requirements and high computational costs.The literature includes much research on feature selection for supervised learning.However,feature selection for unsupervised learning has only recently been studied.Finding the subset of features in unsupervised learning that enhances the performance is challenging since the clusters are indeterminate.This work proposes a hybrid technique for unsupervised feature selection called GAk-MEANS,which combines the genetic algorithm(GA)approach with the classical k-Means algorithm.In the proposed algorithm,a new fitness func-tion is designed in addition to new smart crossover and mutation operators.The effectiveness of this algorithm is demonstrated on various datasets.Fur-thermore,the performance of GAk-MEANS has been compared with other genetic algorithms,such as the genetic algorithm using the Sammon Error Function and the genetic algorithm using the Sum of Squared Error Function.Additionally,the performance of GAk-MEANS is compared with the state-of-the-art statistical unsupervised feature selection techniques.Experimental results show that GAk-MEANS consistently selects subsets of features that result in better classification accuracy compared to others.In particular,GAk-MEANS is able to significantly reduce the size of the subset of selected features by an average of 86.35%(72%–96.14%),which leads to an increase of the accuracy by an average of 3.78%(1.05%–6.32%)compared to using all features.When compared with the genetic algorithm using the Sammon Error Function,GAk-MEANS is able to reduce the size of the subset of selected features by 41.29%on average,improve the accuracy by 5.37%,and reduce the time by 70.71%.When compared with the genetic algorithm using the Sum of Squared Error Function,GAk-MEANS on average is able to reduce the size of the subset of selected features by 15.91%,and improve the accuracy by 9.81%,but the time is increased by a factor of 3.When compared with the machine-learning based methods,we observed that GAk-MEANS is able to increase the accuracy by 13.67%on average with an 88.76%average increase in time. 展开更多
关键词 Genetic algorithm unsupervised feature selection k-means clustering
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Multiple Parameter Based Clustering (MPC): Prospective Analysis for Effective Clustering in Wireless Sensor Network (WSN) Using K-Means Algorithm
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作者 Md. Asif Khan Israfil Tamim +1 位作者 Emdad Ahmed M. Abdul Awal 《Wireless Sensor Network》 2012年第1期18-24,共7页
In wireless sensor network cluster architecture is useful because of its inherent suitability for data fusion. In this paper we represent a new approach called Multiple Parameter based Clustering (MPC) embedded with t... In wireless sensor network cluster architecture is useful because of its inherent suitability for data fusion. In this paper we represent a new approach called Multiple Parameter based Clustering (MPC) embedded with the traditional k-means algorithm which takes different parameters (Node energy level, Euclidian distance from the base station, RSSI, Latency of data to reach base station) into consideration to form clusters. Then the effectiveness of the clusters is evaluated based on the uniformity of the node distribution, Node range per cluster, Intra and Inter cluster distance and required energy level of each centroid. Our result shows that by varying multiple parameters we can create clusters with more uniformly distributed nodes, minimize intra and maximize inter cluster distance and elect less power consuming centroid. 展开更多
关键词 k-means algorithm Energy Efficient UNIFORM Distribution RSSI LATENCY
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Enhanced KOCED Routing Protocol with K-means Algorithm
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作者 SeaYoung Park Jong-Yong Lee Daesung Lee 《Computers, Materials & Continua》 SCIE EI 2021年第6期4019-4037,共19页
Replacing or recharging batteries in the sensor nodes of a wireless sensor network(WSN)is a significant challenge.Therefore,efficient power utilization by sensors is a critical requirement,and it is closely related to... Replacing or recharging batteries in the sensor nodes of a wireless sensor network(WSN)is a significant challenge.Therefore,efficient power utilization by sensors is a critical requirement,and it is closely related to the life span of the network.Once a sensor node consumes all its energy,it will no longer function properly.Therefore,various protocols have been proposed to minimize the energy consumption of sensors and thus prolong the network operation.Recently,clustering algorithms combined with artificial intelligence have been proposed for this purpose.In particular,various protocols employ the K-means clustering algorithm,which is a machine learning method.The number of clustering configurations required by the K-means clustering algorithm is greater than that required by the hierarchical algorithm.Further,the selection of the cluster heads considers only the residual energy of the nodes without accounting for the transmission distance to the base station.In terms of energy consumption,the residual energy of each node,the transmission distance,the cluster head location,and the central relative position within the cluster should be considered simultaneously.In this paper,we propose the KOCED(K-means with Optimal clustering for WSN considering Centrality,Energy,and Distance)protocol,which considers the residual energy of nodes as well as the distances to the central point of the cluster and the base station.A performance comparison shows that the KOCED protocol outperforms the LEACH protocol by 259%(223 rounds)for first node dead(FND)and 164%(280 rounds)with 80%alive nodes. 展开更多
关键词 WSN routing protocol k-means K-optimal LEACH KCE KOCED
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Improvement of energy resolution of x-ray transition-edge sensor using K-means algorithm and Wiener filter
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作者 马卿效 张文 +8 位作者 李佩展 王争 冯志发 杨心开 钟家强 缪巍 任远 李婧 史生才 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期695-699,共5页
We develop an x-ray Ti/Au transition-edge sensor(TES)with an Au absorber deposited on the center of TES and improved its energy resolution using the K-means clustering algorithm in combination with Wiener filter.We fi... We develop an x-ray Ti/Au transition-edge sensor(TES)with an Au absorber deposited on the center of TES and improved its energy resolution using the K-means clustering algorithm in combination with Wiener filter.We firstly extract the main parameters of each recorded pulse trace,which are adopted to classify these traces into several clusters in the K-means clustering algorithm.Then real traces are selected for energy resolution analysis.Following the baseline correction,the Wiener filter is used to improve the signal-to-noise ratio.Although the silicon underneath the TES has not been etched to reduce the thermal conductance,the energy resolution of the developed x-ray TES is improved from 94 eV to 44 eV at 5.9 keV. 展开更多
关键词 transition-edge sensors energy resolution k-means clustering Wiener filter
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Finding Community Structure in Networks Using a Shortest-Path-Based k-Means Algorithm
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作者 Jinglu GAO 《Journal of Mathematical Research with Applications》 CSCD 2013年第3期288-296,共9页
We consider the problem of detecting the community structure in a complex network, groups of nodes with a higher-than-average density of edges connecting them. In this paper we use the simulated annealing strategy to ... We consider the problem of detecting the community structure in a complex network, groups of nodes with a higher-than-average density of edges connecting them. In this paper we use the simulated annealing strategy to maximize the modularity, which has been indicated as a robust benefit function, associating with a shortest-path-based k-means iterative procedure for network partition. The proposed algorithm can not only find the communities, but also identify the nodes which occupy central positions under the metric of the shortest path within the communities to which they belong. The optimal number of communities can be automatically determined without any prior knowledge about the network structure. The applications to both artificial and real-world networks demonstrate the effectiveness of our algorithm. 展开更多
关键词 community structure MODULARITY shortest path k-means simulated annealing.
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Parallel K-Means Algorithm for Shared Memory Multiprocessors
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作者 Tayfun Kucukyilmaz 《Journal of Computer and Communications》 2014年第11期15-23,共9页
Clustering is the task of assigning a set of instances into groups in such a way that is dissimilarity of instances within each group is minimized. Clustering is widely used in several areas such as data mining, patte... Clustering is the task of assigning a set of instances into groups in such a way that is dissimilarity of instances within each group is minimized. Clustering is widely used in several areas such as data mining, pattern recognition, machine learning, image processing, computer vision and etc. K-means is a popular clustering algorithm which partitions instances into a fixed number clusters in an iterative fashion. Although k-means is considered to be a poor clustering algorithm in terms of result quality, due to its simplicity, speed on practical applications, and iterative nature it is selected as one of the top 10 algorithms in data mining [1]. Parallelization of k-means is also studied during the last 2 decades. Most of these work concentrate on shared-nothing architectures. With the advent of current technological advances on GPU technology, implementation of the k-means algorithm on shared memory architectures recently start to attract some attention. However, to the best of our knowledge, no in-depth analysis on the performance of k-means on shared memory multiprocessors is done in the literature. In this work, our aim is to fill this gap by providing theoretical analysis on the performance of k-means algorithm and presenting extensive tests on a shared memory architecture. 展开更多
关键词 k-means CLUSTERING Data MINING SHARED MEMORY Systems High Performance
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Study on the Application of K-Means Algorithm Implemented Hadoop Platform to the Library Work in Colleges and Universities
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作者 Ping LI 《International Journal of Technology Management》 2013年第8期86-89,共4页
In this paper, the borrowing data of readers is analyzed and studied by taking K-Means algorithm as an example and implementing this algorithm in Hadoop calculation platform, and data mining technology is effectively ... In this paper, the borrowing data of readers is analyzed and studied by taking K-Means algorithm as an example and implementing this algorithm in Hadoop calculation platform, and data mining technology is effectively and closely combined with personalized library service through the experimental data. 展开更多
关键词 Data Mining HADOOP LIBRARY Mahout Map/Reduce k-means
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An Improved K-means Algorithm for Clustering Categorical Data 被引量:1
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作者 Ming Lei Pilian He Zhichao Li 《通讯和计算机(中英文版)》 2006年第8期20-24,共5页
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基于k-means算法的聚类个数确定方法改进 被引量:2
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作者 王丙参 王国长 魏艳华 《统计与决策》 北大核心 2025年第7期59-64,共6页
文章基于k-means算法探讨了最优聚类个数k*的确定方法:第一类是统计量方法;第二类是聚类算法不稳定性方法,即基于两次聚类结果间的距离,利用交叉验证、随机抽样取交集、自助法来构建聚类算法估计不稳定性指标,并根据投票、最小化均值方... 文章基于k-means算法探讨了最优聚类个数k*的确定方法:第一类是统计量方法;第二类是聚类算法不稳定性方法,即基于两次聚类结果间的距离,利用交叉验证、随机抽样取交集、自助法来构建聚类算法估计不稳定性指标,并根据投票、最小化均值方法确定k^(*)。数值模拟结果显示:在给定k^(*)的情况下,聚类结果与标签的距离或相似度可作为评价聚类结果的指标,为聚类算法评价提供了新的借鉴;基于k-means算法确定k^(*)的前提是数据集根据欧氏距离可明显分为几簇,相对而言,聚类算法不稳定性方法优于统计量方法;对于不稳定性指标,交叉验证估计方法与随机抽样取交集估计方法对抽样个数稳健,抽样个数依次建议略少于样本容量的1/3、80%;自助抽样估计方法由于利用了全部样本,因此效率更高;4种不稳定性指标没有显著差异,投票与最小化均值方法也没有显著差异。 展开更多
关键词 k-means算法 聚类个数 统计量 不稳定性
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基于深度自适应K-means++算法的电抗器声纹聚类方法 被引量:4
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作者 闵永智 郝大宇 +2 位作者 王果 何怡刚 贺建山 《电力系统保护与控制》 北大核心 2025年第8期1-13,共13页
在高压并联电抗器声纹信号监测系统中,长时海量无标签声纹的高维非平稳性导致特征提取困难、无监督聚类适应性差。由此提出了一种基于深度自适应K-means++算法(deep adaptive K-means++clustering algorithm,DAKCA)的750 kV电抗器声纹... 在高压并联电抗器声纹信号监测系统中,长时海量无标签声纹的高维非平稳性导致特征提取困难、无监督聚类适应性差。由此提出了一种基于深度自适应K-means++算法(deep adaptive K-means++clustering algorithm,DAKCA)的750 kV电抗器声纹聚类方法。首先通过采用两阶段无监督策略微调的改进堆叠稀疏自编码器(stacked sparse autoencoder,SSAE),对快速傅里叶变换后的归一化频域数据提取电抗器原始声纹32维深度特征。进一步提出了依据最近邻聚类有效性指标(clustering validation index based on nearest neighbors,CVNN)的自适应K-means++聚类算法,构建了能自适应确定最优聚类个数的电抗器声纹聚类模型。最后通过西北地区某750 kV电抗器实测声纹数据集进行了验证。结果表明,DAKCA算法对无标签声纹数据在不同样本均衡程度下能够稳定提取32维深度特征,并实现最优聚类,为直接高效利用电抗器无标签声纹数据提供了参考。 展开更多
关键词 750 kV电抗器 声纹聚类 自适应聚类算法 稀疏自编码器 深度自适应k-means++算法
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