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Plant Leaf Diseases Classification Using Improved K-Means Clustering and SVM Algorithm for Segmentation
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作者 Mona Jamjoom Ahmed Elhadad +1 位作者 Hussein Abulkasim Safia Abbas 《Computers, Materials & Continua》 SCIE EI 2023年第7期367-382,共16页
Several pests feed on leaves,stems,bases,and the entire plant,causing plant illnesses.As a result,it is vital to identify and eliminate the disease before causing any damage to plants.Manually detecting plant disease ... Several pests feed on leaves,stems,bases,and the entire plant,causing plant illnesses.As a result,it is vital to identify and eliminate the disease before causing any damage to plants.Manually detecting plant disease and treating it is pretty challenging in this period.Image processing is employed to detect plant disease since it requires much effort and an extended processing period.The main goal of this study is to discover the disease that affects the plants by creating an image processing system that can recognize and classify four different forms of plant diseases,including Phytophthora infestans,Fusarium graminearum,Puccinia graminis,tomato yellow leaf curl.Therefore,this work uses the Support vector machine(SVM)classifier to detect and classify the plant disease using various steps like image acquisition,Pre-processing,Segmentation,feature extraction,and classification.The gray level co-occurrence matrix(GLCM)and the local binary pattern features(LBP)are used to identify the disease-affected portion of the plant leaf.According to experimental data,the proposed technology can correctly detect and diagnose plant sickness with a 97.2 percent accuracy. 展开更多
关键词 SVM machine learning GLCM algorithm k-means clustering LBP
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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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Improved k-means clustering algorithm 被引量:16
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作者 夏士雄 李文超 +2 位作者 周勇 张磊 牛强 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期435-438,共4页
In allusion to the disadvantage of having to obtain the number of clusters of data sets in advance and the sensitivity to selecting initial clustering centers in the k-means algorithm, an improved k-means clustering a... In allusion to the disadvantage of having to obtain the number of clusters of data sets in advance and the sensitivity to selecting initial clustering centers in the k-means algorithm, an improved k-means clustering algorithm is proposed. First, the concept of a silhouette coefficient is introduced, and the optimal clustering number Kopt of a data set with unknown class information is confirmed by calculating the silhouette coefficient of objects in clusters under different K values. Then the distribution of the data set is obtained through hierarchical clustering and the initial clustering-centers are confirmed. Finally, the clustering is completed by the traditional k-means clustering. By the theoretical analysis, it is proved that the improved k-means clustering algorithm has proper computational complexity. The experimental results of IRIS testing data set show that the algorithm can distinguish different clusters reasonably and recognize the outliers efficiently, and the entropy generated by the algorithm is lower. 展开更多
关键词 clustering k-means algorithm silhouette coefficient
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An efficient enhanced k-means clustering algorithm 被引量:30
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作者 FAHIM A.M SALEM A.M +1 位作者 TORKEY F.A RAMADAN M.A 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第10期1626-1633,共8页
In k-means clustering, we are given a set of n data points in d-dimensional space R^d and an integer k and the problem is to determine a set of k points in R^d, called centers, so as to minimize the mean squared dista... In k-means clustering, we are given a set of n data points in d-dimensional space R^d and an integer k and the problem is to determine a set of k points in R^d, called centers, so as to minimize the mean squared distance from each data point to its nearest center. In this paper, we present a simple and efficient clustering algorithm based on the k-means algorithm, which we call enhanced k-means algorithm. This algorithm is easy to implement, requiring a simple data structure to keep some information in each iteration to be used in the next iteration. Our experimental results demonstrated that our scheme can improve the computational speed of the k-means algorithm by the magnitude in the total number of distance calculations and the overall time of computation. 展开更多
关键词 clustering algorithms cluster analysis k-means algorithm Data analysis
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Development of slope mass rating system using K-means and fuzzy c-means clustering algorithms 被引量:1
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作者 Jalali Zakaria 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第6期959-966,共8页
Classification systems such as Slope Mass Rating(SMR) are currently being used to undertake slope stability analysis. In SMR classification system, data is allocated to certain classes based on linguistic and experien... Classification systems such as Slope Mass Rating(SMR) are currently being used to undertake slope stability analysis. In SMR classification system, data is allocated to certain classes based on linguistic and experience-based criteria. In order to eliminate linguistic criteria resulted from experience-based judgments and account for uncertainties in determining class boundaries developed by SMR system,the system classification results were corrected using two clustering algorithms, namely K-means and fuzzy c-means(FCM), for the ratings obtained via continuous and discrete functions. By applying clustering algorithms in SMR classification system, no in-advance experience-based judgment was made on the number of extracted classes in this system, and it was only after all steps of the clustering algorithms were accomplished that new classification scheme was proposed for SMR system under different failure modes based on the ratings obtained via continuous and discrete functions. The results of this study showed that, engineers can achieve more reliable and objective evaluations over slope stability by using SMR system based on the ratings calculated via continuous and discrete functions. 展开更多
关键词 SMR based on continuous functions Slope stability analysis k-means and FCM clustering algorithms Validation of clustering algorithms Sangan iron ore mines
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Hybrid Genetic Algorithm with K-Means for Clustering Problems 被引量:1
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作者 Ahamed Al Malki Mohamed M. Rizk +1 位作者 M. A. El-Shorbagy A. A. Mousa 《Open Journal of Optimization》 2016年第2期71-83,共14页
The K-means method is one of the most widely used clustering methods and has been implemented in many fields of science and technology. One of the major problems of the k-means algorithm is that it may produce empty c... The K-means method is one of the most widely used clustering methods and has been implemented in many fields of science and technology. One of the major problems of the k-means algorithm is that it may produce empty clusters depending on initial center vectors. Genetic Algorithms (GAs) are adaptive heuristic search algorithm based on the evolutionary principles of natural selection and genetics. This paper presents a hybrid version of the k-means algorithm with GAs that efficiently eliminates this empty cluster problem. Results of simulation experiments using several data sets prove our claim. 展开更多
关键词 cluster Analysis Genetic algorithm k-means
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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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A State of Art Analysis of Telecommunication Data by k-Means and k-Medoids Clustering Algorithms
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作者 T. Velmurugan 《Journal of Computer and Communications》 2018年第1期190-202,共13页
Cluster analysis is one of the major data analysis methods widely used for many practical applications in emerging areas of data mining. A good clustering method will produce high quality clusters with high intra-clus... Cluster analysis is one of the major data analysis methods widely used for many practical applications in emerging areas of data mining. A good clustering method will produce high quality clusters with high intra-cluster similarity and low inter-cluster similarity. Clustering techniques are applied in different domains to predict future trends of available data and its uses for the real world. This research work is carried out to find the performance of two of the most delegated, partition based clustering algorithms namely k-Means and k-Medoids. A state of art analysis of these two algorithms is implemented and performance is analyzed based on their clustering result quality by means of its execution time and other components. Telecommunication data is the source data for this analysis. The connection oriented broadband data is given as input to find the clustering quality of the algorithms. Distance between the server locations and their connection is considered for clustering. Execution time for each algorithm is analyzed and the results are compared with one another. Results found in comparison study are satisfactory for the chosen application. 展开更多
关键词 k-means algorithm k-Medoids algorithm DATA clustering Time COMPLEXITY TELECOMMUNICATION DATA
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P-ROCK: A Sustainable Clustering Algorithm for Large Categorical Datasets
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作者 Ayman Altameem Ramesh Chandra Poonia +2 位作者 Ankit Kumar Linesh Raja Abdul Khader Jilani Saudagar 《Intelligent Automation & Soft Computing》 SCIE 2023年第1期553-566,共14页
Data clustering is crucial when it comes to data processing and analytics.The new clustering method overcomes the challenge of evaluating and extracting data from big data.Numerical or categorical data can be grouped.... Data clustering is crucial when it comes to data processing and analytics.The new clustering method overcomes the challenge of evaluating and extracting data from big data.Numerical or categorical data can be grouped.Existing clustering methods favor numerical data clustering and ignore categorical data clustering.Until recently,the only way to cluster categorical data was to convert it to a numeric representation and then cluster it using current numeric clustering methods.However,these algorithms could not use the concept of categorical data for clustering.Following that,suggestions for expanding traditional categorical data processing methods were made.In addition to expansions,several new clustering methods and extensions have been proposed in recent years.ROCK is an adaptable and straightforward algorithm for calculating the similarity between data sets to cluster them.This paper aims to modify the algo-rithm by creating a parameterized version that takes specific algorithm parameters as input and outputs satisfactory cluster structures.The parameterized ROCK algorithm is the name given to the modified algorithm(P-ROCK).The proposed modification makes the original algorithm moreflexible by using user-defined parameters.A detailed hypothesis was developed later validated with experimental results on real-world datasets using our proposed P-ROCK algorithm.A comparison with the original ROCK algorithm is also provided.Experiment results show that the proposed algorithm is on par with the original ROCK algorithm with an accuracy of 97.9%.The proposed P-ROCK algorithm has improved the runtime and is moreflexible and scalable. 展开更多
关键词 ROCK k-means algorithm clustering approaches unsupervised learning K-histogram
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基于改进的K-means聚类和深度神经网络的轴承故障诊断算法研究 被引量:2
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作者 孟洪颜 胡玉坤 +2 位作者 冯双 周冬 王艳春 《黑龙江大学工程学报(中英俄文)》 2023年第4期55-63,72,共10页
提出了一种改进K-means聚类算法,使用该方法对轴承振动数据进行聚类和基于深度神经网络的半监督学习的故障诊断研究。对轴承振动数据进行时域和频域处理,得到28维的时域和频域特征数据;利用提出的算法对高维特征数据进行聚类处理,得到... 提出了一种改进K-means聚类算法,使用该方法对轴承振动数据进行聚类和基于深度神经网络的半监督学习的故障诊断研究。对轴承振动数据进行时域和频域处理,得到28维的时域和频域特征数据;利用提出的算法对高维特征数据进行聚类处理,得到伪标签,建立特征数据和伪标签对应的数据集;利用神经网络对具有伪标签的特征数据进行半监督学习,实现对不同轴承振动状态的高精度识别。通过对比聚类指标,提出的算法较好地改善了聚类效果;用伪标签数据训练神经网络,将预测的结果与真实数据比较,精度可达96.2%,可100%区分正常状态和故障状态。 展开更多
关键词 滚动轴承 故障诊断 聚类算法 神经网络 半监督学习
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Flexible resource allocation optimization model considering global K-means load clustering and renewable-energy consumption
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作者 Jie Jiao Puyu He +3 位作者 Yuhong Zhang Jiyuan Zhang Zhuhan Long Hanjing Liu 《Clean Energy》 EI CSCD 2024年第5期129-143,共15页
Vigorously developing flexible resources in power systems will be the key to building a new power system and realizing energy trans-formation.The investment construction cost and operation cost of various flexible res... Vigorously developing flexible resources in power systems will be the key to building a new power system and realizing energy trans-formation.The investment construction cost and operation cost of various flexible resources are different,and the adjustment ability is different in different timescales.Therefore,the optimization of complementary allocation of various resources needs to take into account the economy and adjustment ability of different resources.In this paper,the global K-means load clustering model is pro-posed and the 365-day net load is reduced to eight typical daily net loads by clustering.Secondly,a two-level optimization model of flexible resource complementary allocation considering wind power and photovoltaic consumption is constructed.The flexible resources involved include the flexible transformation of thermal power,hydropower,pumped storage,energy storage,and demand response.The upper-layer model optimizes the capacity allocation of various flexible resources with the minimum investment and construction cost as the goal and the lower layer optimizes the operating output of various units with the minimum operating cost as the goal.The results of the example analysis show that the flexible capacity of thermal power units has nothing to do with the abandonment rate of renewable energy.As the abandonment rate of renewable energy decreases,the optimal capacity of pumped storage,electrochemical energy storage,and hydropower units increases.When the power-abandonment rate of renewable energy is 5%,the optimal allocation capacity of thermal power flexibility transformation,pumped storage,electrochemical energy storage,hydropower unit,and adjustable load in Province A is 5313,17090,5830,72113,and 4250 MW,respectively.Under the condition that the renewable-energy abandonment rate is 0,5%,and 10%respectively,the configured capacity of pumped storage is 20000,17090,and 14847 MW,respectively. 展开更多
关键词 wind power photovoltaic power k-means clustering algorithm flexible resources complementary configuration operation optimization
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Distance function selection in several clustering algorithms
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作者 LUYu 《Journal of Chongqing University》 CAS 2004年第1期47-50,共4页
Most clustering algorithms need to describe the similarity of objects by a predefined distance function. Three distance functions which are widely used in two traditional clustering algorithms k-means and hierarchical... Most clustering algorithms need to describe the similarity of objects by a predefined distance function. Three distance functions which are widely used in two traditional clustering algorithms k-means and hierarchical clustering were investigated. Both theoretical analysis and detailed experimental results were given. It is shown that a distance function greatly affects clustering results and can be used to detect the outlier of a cluster by the comparison of such different results and give the shape information of clusters. In practice situation, it is suggested to use different distance function separately, compare the clustering results and pick out the 搒wing points? And such points may leak out more information for data analysts. 展开更多
关键词 distance function clustering algorithms k-means DENDROGRAM data mining
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Hybrid Clustering Algorithms with GRASP to Construct an Initial Solution for the MVPPDP
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作者 Abeer I.Alhujaylan Manar I.Hosny 《Computers, Materials & Continua》 SCIE EI 2020年第3期1025-1051,共27页
Mobile commerce(m-commerce)contributes to increasing the popularity of electronic commerce(e-commerce),allowing anybody to sell or buy goods using a mobile device or tablet anywhere and at any time.As demand for e-com... Mobile commerce(m-commerce)contributes to increasing the popularity of electronic commerce(e-commerce),allowing anybody to sell or buy goods using a mobile device or tablet anywhere and at any time.As demand for e-commerce increases tremendously,the pressure on delivery companies increases to organise their transportation plans to achieve profits and customer satisfaction.One important planning problem in this domain is the multi-vehicle profitable pickup and delivery problem(MVPPDP),where a selected set of pickup and delivery customers need to be served within certain allowed trip time.In this paper,we proposed hybrid clustering algorithms with the greedy randomised adaptive search procedure(GRASP)to construct an initial solution for the MVPPDP.Our approaches first cluster the search space in order to reduce its dimensionality,then use GRASP to build routes for each cluster.We compared our results with state-of-the-art construction heuristics that have been used to construct initial solutions to this problem.Experimental results show that our proposed algorithms contribute to achieving excellent performance in terms of both quality of solutions and processing time. 展开更多
关键词 Multi-vehicle profitable pickup and delivery problem k-means clustering algorithm ant colony optimisation greedy randomised adaptive search procedure metaheuristic algorithms
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Binary-Real Coded Genetic Algorithm Based <i>k</i>-Means Clustering for Unit Commitment Problem
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作者 Mai A. Farag M. A. El-Shorbagy +2 位作者 I. M. El-Desoky A. A. El-Sawy A. A. Mousa 《Applied Mathematics》 2015年第11期1873-1890,共18页
This paper presents a new algorithm for solving unit commitment (UC) problems using a binary-real coded genetic algorithm based on k-means clustering technique. UC is a NP-hard nonlinear mixed-integer optimization pro... This paper presents a new algorithm for solving unit commitment (UC) problems using a binary-real coded genetic algorithm based on k-means clustering technique. UC is a NP-hard nonlinear mixed-integer optimization problem, encountered as one of the toughest problems in power systems, in which some power generating units are to be scheduled in such a way that the forecasted demand is met at minimum production cost over a time horizon. In the proposed algorithm, the algorithm integrates the main features of a binary-real coded genetic algorithm (GA) and k-means clustering technique. The binary coded GA is used to obtain a feasible commitment schedule for each generating unit;while the power amounts generated by committed units are determined by using real coded GA for the feasible commitment obtained in each interval. k-means clustering algorithm divides population into a specific number of subpopulations with dynamic size. In this way, using k-means clustering algorithm allows the use of different GA operators with the whole population and avoids the local problem minima. The effectiveness of the proposed technique is validated on a test power system available in the literature. The proposed algorithm performance is found quite satisfactory in comparison with the previously reported results. 展开更多
关键词 Unit COMMITMENT (UC) GENETIC algorithm (GA) k-means clustering Technique
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Application Progress of Signal Clustering Algorithm
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作者 Chujie Deng Jing Qi +1 位作者 Mei Li Xuanchicheng Luo 《国际计算机前沿大会会议论文集》 2016年第1期57-58,共2页
Clustering algorithm, which is a statistical analysis method for research in classifications, plays an important role in data mining algorithm. Clustering algorithm based on similarity, and is easy to combine with oth... Clustering algorithm, which is a statistical analysis method for research in classifications, plays an important role in data mining algorithm. Clustering algorithm based on similarity, and is easy to combine with other methods in optimization. In this review, signal clustering algorithm is introduced by discussing of the clustering parametric in different signal clustering algorithms. In order to develop traditional algorithm, we introduce a series of improvement, development and application of the methods in recent years. Finally, we make an outlook of the future direction and content of the research in this field. 展开更多
关键词 SIGNAL clustering algorithm k-means FCM
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Hybrid Clustering Using Firefly Optimization and Fuzzy C-Means Algorithm
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作者 Krishnamoorthi Murugasamy Kalamani Murugasamy 《Circuits and Systems》 2016年第9期2339-2348,共10页
Classifying the data into a meaningful group is one of the fundamental ways of understanding and learning the valuable information. High-quality clustering methods are necessary for the valuable and efficient analysis... Classifying the data into a meaningful group is one of the fundamental ways of understanding and learning the valuable information. High-quality clustering methods are necessary for the valuable and efficient analysis of the increasing data. The Firefly Algorithm (FA) is one of the bio-inspired algorithms and it is recently used to solve the clustering problems. In this paper, Hybrid F-Firefly algorithm is developed by combining the Fuzzy C-Means (FCM) with FA to improve the clustering accuracy with global optimum solution. The Hybrid F-Firefly algorithm is developed by incorporating FCM operator at the end of each iteration in FA algorithm. This proposed algorithm is designed to utilize the goodness of existing algorithm and to enhance the original FA algorithm by solving the shortcomings in the FCM algorithm like the trapping in local optima and sensitive to initial seed points. In this research work, the Hybrid F-Firefly algorithm is implemented and experimentally tested for various performance measures under six different benchmark datasets. From the experimental results, it is observed that the Hybrid F-Firefly algorithm significantly improves the intra-cluster distance when compared with the existing algorithms like K-means, FCM and FA algorithm. 展开更多
关键词 clustering OPTIMIZATION k-means Fuzzy C-Means Firefly algorithm F-Firefly
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基于改进K-means算法的电网运行断面相似性匹配研究 被引量:12
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作者 梁海平 田潮 +3 位作者 王铁强 曹欣 杨晓东 刘英培 《电力自动化设备》 EI CSCD 北大核心 2019年第7期119-124,140,共7页
为简化电网工作票制定过程中复杂的方案校验工作,降低对电网调度人员工作经验的依赖,提出利用断面特征提取进行电网历史运行断面相似性匹配的方法。首先根据系统运行特点和数据存储格式,采用决策树模型提取、筛选特征变量;然后基于改进... 为简化电网工作票制定过程中复杂的方案校验工作,降低对电网调度人员工作经验的依赖,提出利用断面特征提取进行电网历史运行断面相似性匹配的方法。首先根据系统运行特点和数据存储格式,采用决策树模型提取、筛选特征变量;然后基于改进半监督K-means算法对历史运行断面进行初步相似性聚类,获取有效样本,降低数据规模;最后利用相似性匹配指标体系在聚类结果中为系统当前运行断面匹配到最有参考和利用价值的历史运行断面及其对应决策信息。仿真算例表明,所提方法可以很好地完成运行断面的相似性匹配工作。 展开更多
关键词 工作票 运行断面 半监督k-means算法 相似性匹配指标体系 聚类算法
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A K-Means Clustering-Based Multiple Importance Sampling Algorithm for Integral Global Optimization
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作者 Chen Wang Dong-Hua Wu 《Journal of the Operations Research Society of China》 EI CSCD 2023年第1期157-175,共19页
In this paper, we propose a K-means clustering-based integral level-value estimation algorithm to solve a kind of box-constrained global optimization problem. For this purpose, we introduce the generalized variance fu... In this paper, we propose a K-means clustering-based integral level-value estimation algorithm to solve a kind of box-constrained global optimization problem. For this purpose, we introduce the generalized variance function associated with the level-value of the objective function to be minimized. The variance function has a good property when Newton’s method is used to solve a variance equation resulting by setting the variance function to zero. We prove that the largest root of the variance equation is equal to the global minimum value of the corresponding optimization problem. Based on the K-means clustering algorithm, the multiple importance sampling technique is proposed in the implementable algorithm. The main idea of the cross-entropy method is used to update the parameters of sampling density function. The asymptotic convergence of the algorithm is proved, and the validity of the algorithm is verified by numerical experiments. 展开更多
关键词 Global optimization Generalized variance function Multiple importance sampling k-means clustering algorithm
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一种主动半监督K-means聚类算法的改进策略 被引量:3
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作者 吕峰 柴变芳 +1 位作者 李文斌 王垚 《南京师范大学学报(工程技术版)》 CAS 2018年第2期56-62,共7页
经典的APCKmeans(active pairwise constrained K-means)算法通过主动学习的方式构造must-link约束集和cannot-link约束集作为监督信息进行半监督聚类,提高了结果的准确性.但该算法在样本指派的过程中可能出现指派不是当前最优的问题.... 经典的APCKmeans(active pairwise constrained K-means)算法通过主动学习的方式构造must-link约束集和cannot-link约束集作为监督信息进行半监督聚类,提高了结果的准确性.但该算法在样本指派的过程中可能出现指派不是当前最优的问题.提出一种优先指派标签样本的方法,应用于APCKmeans算法,使用改进后的APCKmeans_I算法实现了使用较少的监督信息取得更好的聚类结果.将改进策略应用于PCKmeans(pairwise constrained K-means)算法,提出改进后的PCKmeans_I算法.通过在UCI基准数据集的实验表明,改进后算法的性能得到明显提升. 展开更多
关键词 主动半监督聚类 成对约束聚类 改进算法
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