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Fuzzy C-Means Algorithm Based on Density Canopy and Manifold Learning
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作者 Jili Chen Hailan Wang Xiaolan Xie 《Computer Systems Science & Engineering》 2024年第3期645-663,共19页
Fuzzy C-Means(FCM)is an effective and widely used clustering algorithm,but there are still some problems.considering the number of clusters must be determined manually,the local optimal solutions is easily influenced ... Fuzzy C-Means(FCM)is an effective and widely used clustering algorithm,but there are still some problems.considering the number of clusters must be determined manually,the local optimal solutions is easily influenced by the random selection of initial cluster centers,and the performance of Euclid distance in complex high-dimensional data is poor.To solve the above problems,the improved FCM clustering algorithm based on density Canopy and Manifold learning(DM-FCM)is proposed.First,a density Canopy algorithm based on improved local density is proposed to automatically deter-mine the number of clusters and initial cluster centers,which improves the self-adaptability and stability of the algorithm.Then,considering that high-dimensional data often present a nonlinear structure,the manifold learning method is applied to construct a manifold spatial structure,which preserves the global geometric properties of complex high-dimensional data and improves the clustering effect of the algorithm on complex high-dimensional datasets.Fowlkes-Mallows Index(FMI),the weighted average of homogeneity and completeness(V-measure),Adjusted Mutual Information(AMI),and Adjusted Rand Index(ARI)are used as performance measures of clustering algorithms.The experimental results show that the manifold learning method is the superior distance measure,and the algorithm improves the clustering accuracy and performs superiorly in the clustering of low-dimensional and complex high-dimensional data. 展开更多
关键词 fuzzy c-means(fcm) cluster center density canopy ISOMAP clustering
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Unknown DDoS Attack Detection with Fuzzy C-Means Clustering and Spatial Location Constraint Prototype Loss
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作者 Thanh-Lam Nguyen HaoKao +2 位作者 Thanh-Tuan Nguyen Mong-Fong Horng Chin-Shiuh Shieh 《Computers, Materials & Continua》 SCIE EI 2024年第2期2181-2205,共25页
Since its inception,the Internet has been rapidly evolving.With the advancement of science and technology and the explosive growth of the population,the demand for the Internet has been on the rise.Many applications i... Since its inception,the Internet has been rapidly evolving.With the advancement of science and technology and the explosive growth of the population,the demand for the Internet has been on the rise.Many applications in education,healthcare,entertainment,science,and more are being increasingly deployed based on the internet.Concurrently,malicious threats on the internet are on the rise as well.Distributed Denial of Service(DDoS)attacks are among the most common and dangerous threats on the internet today.The scale and complexity of DDoS attacks are constantly growing.Intrusion Detection Systems(IDS)have been deployed and have demonstrated their effectiveness in defense against those threats.In addition,the research of Machine Learning(ML)and Deep Learning(DL)in IDS has gained effective results and significant attention.However,one of the challenges when applying ML and DL techniques in intrusion detection is the identification of unknown attacks.These attacks,which are not encountered during the system’s training,can lead to misclassification with significant errors.In this research,we focused on addressing the issue of Unknown Attack Detection,combining two methods:Spatial Location Constraint Prototype Loss(SLCPL)and Fuzzy C-Means(FCM).With the proposed method,we achieved promising results compared to traditional methods.The proposed method demonstrates a very high accuracy of up to 99.8%with a low false positive rate for known attacks on the Intrusion Detection Evaluation Dataset(CICIDS2017)dataset.Particularly,the accuracy is also very high,reaching 99.7%,and the precision goes up to 99.9%for unknown DDoS attacks on the DDoS Evaluation Dataset(CICDDoS2019)dataset.The success of the proposed method is due to the combination of SLCPL,an advanced Open-Set Recognition(OSR)technique,and FCM,a traditional yet highly applicable clustering technique.This has yielded a novel method in the field of unknown attack detection.This further expands the trend of applying DL and ML techniques in the development of intrusion detection systems and cybersecurity.Finally,implementing the proposed method in real-world systems can enhance the security capabilities against increasingly complex threats on computer networks. 展开更多
关键词 CYBERSECURITY DDoS unknown attack detection machine learning deep learning incremental learning convolutional neural networks(CNN) open-set recognition(OSR) spatial location constraint prototype loss fuzzy c-means CICIDS2017 CICDDoS2019
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Fuzzy c-means text clustering based on topic concept sub-space 被引量:3
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作者 吉翔华 陈超 +1 位作者 邵正荣 俞能海 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期439-442,共4页
To improve the accuracy of text clustering, fuzzy c-means clustering based on topic concept sub-space (TCS2FCM) is introduced for classifying texts. Five evaluation functions are combined to extract key phrases. Con... To improve the accuracy of text clustering, fuzzy c-means clustering based on topic concept sub-space (TCS2FCM) is introduced for classifying texts. Five evaluation functions are combined to extract key phrases. Concept phrases, as well as the descriptions of final clusters, are presented using WordNet origin from key phrases. Initial centers and membership matrix are the most important factors affecting clustering performance. Orthogonal concept topic sub-spaces are built with the topic concept phrases representing topics of the texts and the initialization of centers and the membership matrix depend on the concept vectors in sub-spaces. The results show that, different from random initialization of traditional fuzzy c-means clustering, the initialization related to text content contributions can improve clustering precision. 展开更多
关键词 TCS2fcm topic concept space fuzzy c-means clustering text clustering
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ALLIED FUZZY c-MEANS CLUSTERING MODEL 被引量:2
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作者 武小红 周建江 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第3期208-213,共6页
A novel model of fuzzy clustering, i.e. an allied fuzzy c means (AFCM) model is proposed based on the combination of advantages of fuzzy c means (FCM) and possibilistic c means (PCM) clustering. PCM is sensitive... A novel model of fuzzy clustering, i.e. an allied fuzzy c means (AFCM) model is proposed based on the combination of advantages of fuzzy c means (FCM) and possibilistic c means (PCM) clustering. PCM is sensitive to initializations and often generates coincident clusters. AFCM overcomes this shortcoming and it is an ex tension of PCM. Membership and typicality values can be simultaneously produced in AFCM. Experimental re- suits show that noise data can be well processed, coincident clusters are avoided and clustering accuracy is better. 展开更多
关键词 fuzzy c-means clustering possibilistic c means clustering allied fuzzy c-means clustering
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Fuzzy C-Means算法中隶属度信息在特征空间的分布特性分析及改进方法 被引量:2
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作者 胡世英 周源华 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 1999年第1期67-72,共6页
首先推导了FuzzyC-Means算法在特征空间的迭代公式,然后就其隶属度信息在特征空间的分布缺陷提出两种改进方法:一是通过引入选择注意性参数控制隶属度信息的分布;二是从条件概率出发构造类置信度取代原隶属度.实验表明... 首先推导了FuzzyC-Means算法在特征空间的迭代公式,然后就其隶属度信息在特征空间的分布缺陷提出两种改进方法:一是通过引入选择注意性参数控制隶属度信息的分布;二是从条件概率出发构造类置信度取代原隶属度.实验表明这两种方法均起到了较好的效果. 展开更多
关键词 fuzzy 隶属度 选择注意性参数 置信度 fcm算法
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农业机器人采摘目标识别技术研究——基于FCM模糊聚类算法 被引量:1
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作者 冯高峰 《农机化研究》 北大核心 2024年第3期30-33,41,共5页
介绍了FCM(Fuzzy C-Means)模糊聚类算法的原理,采用权重分配的方法对该算法进行了改进,通过建立模糊的相似矩阵,对目标对象的特征聚类图进行分析,并引入隶属度矩阵对FCM算法进行优化,以加快算法的迭代速度。实验结果表明:农业机器人采... 介绍了FCM(Fuzzy C-Means)模糊聚类算法的原理,采用权重分配的方法对该算法进行了改进,通过建立模糊的相似矩阵,对目标对象的特征聚类图进行分析,并引入隶属度矩阵对FCM算法进行优化,以加快算法的迭代速度。实验结果表明:农业机器人采用该方法对农作物轮廓分割识别度较高,算法计算效率较快,验证了其可靠性,该方法可用于目标农作物的分割和目标识别。 展开更多
关键词 农业机器人 fcm 模糊聚类 隶属度矩阵 目标识别
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基于改进FCM的冲压件缺陷图像分割算法
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作者 张玉杰 高晗 《计算机工程》 CAS CSCD 北大核心 2024年第10期342-351,共10页
在工业质检过程中,冲压件缺陷图像分割作为缺陷检测的重要环节,直接影响缺陷检测效果。而传统的模糊C均值(FCM)聚类算法未考虑到空间邻域信息,对于噪声干扰较为敏感,导致分割精度较差,且其整体易受初始值的影响,造成收敛速度变慢。针对... 在工业质检过程中,冲压件缺陷图像分割作为缺陷检测的重要环节,直接影响缺陷检测效果。而传统的模糊C均值(FCM)聚类算法未考虑到空间邻域信息,对于噪声干扰较为敏感,导致分割精度较差,且其整体易受初始值的影响,造成收敛速度变慢。针对上述问题,提出一种改进的FCM算法。采用内核诱导距离中的简单两项代替传统的欧氏距离,将原有的空间像素映射到高维特征空间,提高线性可分概率和计算速度;利用图像像素之间的空间相关性,通过引入改进的马尔可夫随机场对FCM目标函数进行修正,提高算法的抗噪能力以及分割精度;采用秃鹰搜索(BES)算法确定FCM的初始聚类中心,提高算法的收敛速度,同时避免算法陷入局部极值的情况。为验证改进FCM算法的性能,选取划分熵、划分系数、Xie_Beni系数以及迭代次数作为评价指标,并与近年来先进的图像分割算法进行对比。实验结果表明,改进FCM算法具有更好的抗噪能力,能得到更好的缺陷分割效果,对工业生产中的冲压件缺陷检测有一定的应用价值。 展开更多
关键词 模糊C均值聚类 工业应用 冲压件缺陷 内核诱导距离 马尔可夫随机场 秃鹰搜索算法
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A New Method of Wind Turbine Bearing Fault Diagnosis Based on Multi-Masking Empirical Mode Decomposition and Fuzzy C-Means Clustering 被引量:10
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作者 Yongtao Hu Shuqing Zhang +3 位作者 Anqi Jiang Liguo Zhang Wanlu Jiang Junfeng Li 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第3期156-167,共12页
Based on Multi-Masking Empirical Mode Decomposition (MMEMD) and fuzzy c-means (FCM) clustering, a new method of wind turbine bearing fault diagnosis FCM-MMEMD is proposed, which can determine the fault accurately and ... Based on Multi-Masking Empirical Mode Decomposition (MMEMD) and fuzzy c-means (FCM) clustering, a new method of wind turbine bearing fault diagnosis FCM-MMEMD is proposed, which can determine the fault accurately and timely. First, FCM clustering is employed to classify the data into different clusters, which helps to estimate whether there is a fault and how many fault types there are. If fault signals exist, the fault vibration signals are then demodulated and decomposed into different frequency bands by MMEMD in order to be analyzed further. In order to overcome the mode mixing defect of empirical mode decomposition (EMD), a novel method called MMEMD is proposed. It is an improvement to masking empirical mode decomposition (MEMD). By adding multi-masking signals to the signals to be decomposed in different levels, it can restrain low-frequency components from mixing in highfrequency components effectively in the sifting process and then suppress the mode mixing. It has the advantages of easy implementation and strong ability of suppressing modal mixing. The fault type is determined by Hilbert envelope finally. The results of simulation signal decomposition showed the high performance of MMEMD. Experiments of bearing fault diagnosis in wind turbine bearing fault diagnosis proved the validity and high accuracy of the new method. 展开更多
关键词 Wind TURBINE BEARING FAULTS diagnosis Multi-masking empirical mode decomposition (MMEMD) fuzzy c-mean (fcm) clustering
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Improved evidential fuzzy c-means method 被引量:4
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作者 JIANG Wen YANG Tian +2 位作者 SHOU Yehang TANG Yongchuan HU Weiwei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第1期187-195,共9页
Dempster-Shafer evidence theory(DS theory) is widely used in brain magnetic resonance imaging(MRI) segmentation,due to its efficient combination of the evidence from different sources. In this paper, an improved MRI s... Dempster-Shafer evidence theory(DS theory) is widely used in brain magnetic resonance imaging(MRI) segmentation,due to its efficient combination of the evidence from different sources. In this paper, an improved MRI segmentation method,which is based on fuzzy c-means(FCM) and DS theory, is proposed. Firstly, the average fusion method is used to reduce the uncertainty and the conflict information in the pictures. Then, the neighborhood information and the different influences of spatial location of neighborhood pixels are taken into consideration to handle the spatial information. Finally, the segmentation and the sensor data fusion are achieved by using the DS theory. The simulated images and the MRI images illustrate that our proposed method is more effective in image segmentation. 展开更多
关键词 average fusion spatial information Dempster-Shafer evidence theory(DS theory) fuzzy c-means(fcm) magnetic resonance imaging(MRI) image segmentation
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Soil pore identification with the adaptive fuzzy C-means method based on computed tomography images 被引量:5
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作者 Yue Zhao Qiaoling Han +1 位作者 Yandong Zhao Jinhao Liu 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第3期1043-1052,共10页
The complex geometry and topology of soil is widely recognised as the key driver in many ecological processes. X-ray computed tomography (CT) provides insight into the internal structure of soil pores automatically an... The complex geometry and topology of soil is widely recognised as the key driver in many ecological processes. X-ray computed tomography (CT) provides insight into the internal structure of soil pores automatically and accurately. Until recently, there have not been methods to identify soil pore structures. This has restricted the development of soil science, particularly regarding pore geometry and spatial distribution. Through the adoption of the fuzzy clustering theory and the establishment of pore identification rules, a novel pore identification method is described to extract pore structures from CT soil images. The robustness of the adaptive fuzzy C-means method (AFCM), the adaptive threshold method, and Image-Pro Plus tools were compared on soil specimens under different conditions, such as frozen, saturated, and dry situations. The results demonstrate that the AFCM method is suitable for identifying pore clusters, especially tiny pores, under various soil conditions. The method would provide an optional technique for the study of soil micromorphology. 展开更多
关键词 CT soil IMAGES fuzzy c-means fuzzy clustering theory PORE IDENTIFICATION rule
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Fuzzy c-means clustering based on spatial neighborhood information for image segmentation 被引量:15
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作者 Yanling Li Yi Shen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第2期323-328,共6页
Fuzzy c-means (FCM) algorithm is one of the most popular methods for image segmentation. However, the standard FCM algorithm is sensitive to noise because of not taking into account the spatial information in the im... Fuzzy c-means (FCM) algorithm is one of the most popular methods for image segmentation. However, the standard FCM algorithm is sensitive to noise because of not taking into account the spatial information in the image. An improved FCM algorithm is proposed to improve the antinoise performance of FCM algorithm. The new algorithm is formulated by incorporating the spatial neighborhood information into the membership function for clustering. The distribution statistics of the neighborhood pixels and the prior probability are used to form a new membership func- tion. It is not only effective to remove the noise spots but also can reduce the misclassified pixels. Experimental results indicate that the proposed algorithm is more accurate and robust to noise than the standard FCM algorithm. 展开更多
关键词 image segmentation fuzzy c-means spatial informa- tion. robust.
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Residual-driven Fuzzy C-Means Clustering for Image Segmentation 被引量:9
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作者 Cong Wang Witold Pedrycz +1 位作者 ZhiWu Li MengChu Zhou 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第4期876-889,共14页
In this paper,we elaborate on residual-driven Fuzzy C-Means(FCM)for image segmentation,which is the first approach that realizes accurate residual(noise/outliers)estimation and enables noise-free image to participate ... In this paper,we elaborate on residual-driven Fuzzy C-Means(FCM)for image segmentation,which is the first approach that realizes accurate residual(noise/outliers)estimation and enables noise-free image to participate in clustering.We propose a residual-driven FCM framework by integrating into FCM a residual-related regularization term derived from the distribution characteristic of different types of noise.Built on this framework,a weighted?2-norm regularization term is presented by weighting mixed noise distribution,thus resulting in a universal residual-driven FCM algorithm in presence of mixed or unknown noise.Besides,with the constraint of spatial information,the residual estimation becomes more reliable than that only considering an observed image itself.Supporting experiments on synthetic,medical,and real-world images are conducted.The results demonstrate the superior effectiveness and efficiency of the proposed algorithm over its peers. 展开更多
关键词 fuzzy c-means image segmentation mixed or unknown noise residual-driven weighted regularization
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Fuzzy C-Means Clustering Based Phonetic Tied-Mixture HMM in Speech Recognition 被引量:1
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作者 徐向华 朱杰 郭强 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第1期16-20,共5页
A fuzzy clustering analysis based phonetic tied-mixture HMM(FPTM) was presented to decrease parameter size and improve robustness of parameter training. FPTM was synthesized from state-tied HMMs by a modified fuzzy C-... A fuzzy clustering analysis based phonetic tied-mixture HMM(FPTM) was presented to decrease parameter size and improve robustness of parameter training. FPTM was synthesized from state-tied HMMs by a modified fuzzy C-means clustering algorithm. Each Gaussian codebook of FPTM was built from Gaussian components within the same root node in phonetic decision tree. The experimental results on large vocabulary Mandarin speech recognition show that compared with conventional phonetic tied-mixture HMM and state-tied HMM with approximately the same number of Gaussian mixtures, FPTM achieves word error rate reductions by 4.84% and 13.02% respectively. Combining the two schemes of mixing weights pruning and Gaussian centers fuzzy merging, a significantly parameter size reduction was achieved with little impact on recognition accuracy. 展开更多
关键词 speech recognition hidden Markov model (HMM) fuzzy c-means (fcm) phonetic decision tree
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Multimode Process Monitoring Based on Fuzzy C-means in Locality Preserving Projection Subspace 被引量:5
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作者 解翔 侍洪波 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第6期1174-1179,共6页
For complex industrial processes with multiple operational conditions, it is important to develop effective monitoring algorithms to ensure the safety of production processes. This paper proposes a novel monitoring st... For complex industrial processes with multiple operational conditions, it is important to develop effective monitoring algorithms to ensure the safety of production processes. This paper proposes a novel monitoring strategy based on fuzzy C-means. The high dimensional historical data are transferred to a low dimensional subspace spanned by locality preserving projection. Then the scores in the novel subspace are classified into several overlapped clusters, each representing an operational mode. The distance statistics of each cluster are integrated though the membership values into a novel BID (Bayesian inference distance) monitoring index. The efficiency and effectiveness of the proposed method are validated though the Tennessee Eastman benchmark process. 展开更多
关键词 multimode process monitoring fuzzy c-means locality preserving projection integrated monitoring index Tennessee Eastman process
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New two-dimensional fuzzy C-means clustering algorithm for image segmentation 被引量:3
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作者 周鲜成 申群太 刘利枚 《Journal of Central South University of Technology》 EI 2008年第6期882-887,共6页
To solve the problem of poor anti-noise performance of the traditional fuzzy C-means (FCM) algorithm in image segmentation, a novel two-dimensional FCM clustering algorithm for image segmentation was proposed. In this... To solve the problem of poor anti-noise performance of the traditional fuzzy C-means (FCM) algorithm in image segmentation, a novel two-dimensional FCM clustering algorithm for image segmentation was proposed. In this method, the image segmentation was converted into an optimization problem. The fitness function containing neighbor information was set up based on the gray information and the neighbor relations between the pixels described by the improved two-dimensional histogram. By making use of the global searching ability of the predator-prey particle swarm optimization, the optimal cluster center could be obtained by iterative optimization, and the image segmentation could be accomplished. The simulation results show that the segmentation accuracy ratio of the proposed method is above 99%. The proposed algorithm has strong anti-noise capability, high clustering accuracy and good segment effect, indicating that it is an effective algorithm for image segmentation. 展开更多
关键词 image segmentation fuzzy c-means clustering particle swarm optimization two-dimensional histogram
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A Fixed Suppressed Rate Selection Method for Suppressed Fuzzy C-Means Clustering Algorithm 被引量:2
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作者 Jiulun Fan Jing Li 《Applied Mathematics》 2014年第8期1275-1283,共9页
Suppressed fuzzy c-means (S-FCM) clustering algorithm with the intention of combining the higher speed of hard c-means clustering algorithm and the better classification performance of fuzzy c-means clustering algorit... Suppressed fuzzy c-means (S-FCM) clustering algorithm with the intention of combining the higher speed of hard c-means clustering algorithm and the better classification performance of fuzzy c-means clustering algorithm had been studied by many researchers and applied in many fields. In the algorithm, how to select the suppressed rate is a key step. In this paper, we give a method to select the fixed suppressed rate by the structure of the data itself. The experimental results show that the proposed method is a suitable way to select the suppressed rate in suppressed fuzzy c-means clustering algorithm. 展开更多
关键词 HARD c-means CLUSTERING ALGORITHM fuzzy c-means CLUSTERING ALGORITHM Suppressed fuzzy c-means CLUSTERING ALGORITHM Suppressed RATE
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A Fast Underwater Optical Image Segmentation Algorithm Based on a Histogram Weighted Fuzzy C-means Improved by PSO 被引量:4
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作者 王士龙 徐玉如 庞永杰 《Journal of Marine Science and Application》 2011年第1期70-75,共6页
The S/N of an underwater image is low and has a fuzzy edge.If using traditional methods to process it directly,the result is not satisfying.Though the traditional fuzzy C-means algorithm can sometimes divide the image... The S/N of an underwater image is low and has a fuzzy edge.If using traditional methods to process it directly,the result is not satisfying.Though the traditional fuzzy C-means algorithm can sometimes divide the image into object and background,its time-consuming computation is often an obstacle.The mission of the vision system of an autonomous underwater vehicle (AUV) is to rapidly and exactly deal with the information about the object in a complex environment for the AUV to use the obtained result to execute the next task.So,by using the statistical characteristics of the gray image histogram,a fast and effective fuzzy C-means underwater image segmentation algorithm was presented.With the weighted histogram modifying the fuzzy membership,the above algorithm can not only cut down on a large amount of data processing and storage during the computation process compared with the traditional algorithm,so as to speed up the efficiency of the segmentation,but also improve the quality of underwater image segmentation.Finally,particle swarm optimization (PSO) described by the sine function was introduced to the algorithm mentioned above.It made up for the shortcomings that the FCM algorithm can not get the global optimal solution.Thus,on the one hand,it considers the global impact and achieves the local optimal solution,and on the other hand,further greatly increases the computing speed.Experimental results indicate that the novel algorithm can reach a better segmentation quality and the processing time of each image is reduced.They enhance efficiency and satisfy the requirements of a highly effective,real-time AUV. 展开更多
关键词 underwater image image segmentation autonomous underwater vehicle (AUV) gray-scale histogram fuzzy c-means real-time effectiveness sine function particle swarm optimization (PSO)
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Watershed classification by remote sensing indices: A fuzzy c-means clustering approach 被引量:10
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作者 Bahram CHOUBIN Karim SOLAIMANI +1 位作者 Mahmoud HABIBNEJAD ROSHAN Arash MALEKIAN 《Journal of Mountain Science》 SCIE CSCD 2017年第10期2053-2063,共11页
Determining the relatively similar hydrological properties of the watersheds is very crucial in order to readily classify them for management practices such as flood and soil erosion control. This study aimed to ident... Determining the relatively similar hydrological properties of the watersheds is very crucial in order to readily classify them for management practices such as flood and soil erosion control. This study aimed to identify homogeneous hydrological watersheds using remote sensing data in western Iran. To achieve this goal, remote sensing indices including SAVI, LAI, NDMI, NDVI and snow cover, were extracted from MODIS data over the period 2000 to 2015. Then, a fuzzy method was used to clustering the watersheds based on the extracted indices. A fuzzy c-mean(FCM) algorithm enabled to classify 38 watersheds in three homogeneous groups.The optimal number of clusters was determined through evaluation of partition coefficient, partition entropy function and trial and error. The results indicated three homogeneous regions identified by the fuzzy c-mean clustering and remote sensing product which are consistent with the variations of topography and climate of the study area. Inherently,the grouped watersheds have similar hydrological properties and are likely to need similar management considerations and measures. 展开更多
关键词 Karkheh watershed fuzzy c-means clustering Watershed classification Homogeneous sub-watersheds
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Kernel fuzzy c-means clustering on energy detection based cooperative spectrum sensing 被引量:2
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作者 Anal Paul Santi P. Maity 《Digital Communications and Networks》 SCIE 2016年第4期196-205,共10页
Cooperation in spectral sensing (SS) offers a fast and reliable detection of primary user (PU) transmission over a frequency spectrum at the expense of increased energy consumption. Since the fusion center (FC) ... Cooperation in spectral sensing (SS) offers a fast and reliable detection of primary user (PU) transmission over a frequency spectrum at the expense of increased energy consumption. Since the fusion center (FC) has to handle a large set of data, a duster based approach, specifically fuzzy c-means clustering (FCM), has been extensively used in energy detection based cooperative spectrum sensing (CSS). However, the performance of FCM degrades at low signal-to-noise ratios (SNR) and in the presence of multiple PUs as energy data patterns at the FC are often found to be non-spherical i.e. overlapping. To address the problem, this work explores the scope of kernel fuzzy c-means (KFCM) on energy detection based CSS through the projection of non-linear input data to a high dimensional feature space. Extensive simulation results are shown to highlight the improved detection of multiple PUs at low SNR with low energy consumption. An improvement in the detection probability by ~6.78% and ~6.96% at -15 dBW and -20 dBW, respectively, is achieved over the existing FCM method. 展开更多
关键词 Cooperative spectrum sensing Kernel fuzzy c-means Energy detection Multiple PU detection
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Partition region-based suppressed fuzzy C-means algorithm 被引量:1
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作者 Kun Zhang Weiren Kong +4 位作者 Peipei Liu Jiao Shi Yu Lei Jie Zou Min Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第5期996-1008,共13页
Aimed at the problem that the traditional suppressed fuzzy C-means clustering algorithms ignore the real needs of different objects, applying the same suppressed parameter for modifying membership degrees of all the o... Aimed at the problem that the traditional suppressed fuzzy C-means clustering algorithms ignore the real needs of different objects, applying the same suppressed parameter for modifying membership degrees of all the objects, a novel partition region-based suppressed fuzzy C-means clustering algorithm with better capacity of adaptability and robustness is proposed in this paper. The model based on the real needs of different objects is built, making it clear to decide whether to proceed with further determination; in addition, the external user-defined suppressed parameter is automatically selected according to the intrinsic structural characteristic of each dataset, making the proposed method become robust to the fluctuations in the incoming dataset and initial conditions. Experimental results show that the proposed method is more robust than its counterparts and overcomes the weakness of the original suppressed clustering algorithm in most cases. 展开更多
关键词 shadowed set suppressed fuzzy c-means clustering automatically parameter selection soft computing techniques
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