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Fuzzy Fruit Fly Optimized Node Quality-Based Clustering Algorithm for Network Load Balancing
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作者 P.Rahul N.Kanthimathi +1 位作者 B.Kaarthick M.Leeban Moses 《Computer Systems Science & Engineering》 SCIE EI 2023年第2期1583-1600,共18页
Recently,the fundamental problem with Hybrid Mobile Ad-hoc Net-works(H-MANETs)is tofind a suitable and secure way of balancing the load through Internet gateways.Moreover,the selection of the gateway and overload of th... Recently,the fundamental problem with Hybrid Mobile Ad-hoc Net-works(H-MANETs)is tofind a suitable and secure way of balancing the load through Internet gateways.Moreover,the selection of the gateway and overload of the network results in packet loss and Delay(DL).For optimal performance,it is important to load balance between different gateways.As a result,a stable load balancing procedure is implemented,which selects gateways based on Fuzzy Logic(FL)and increases the efficiency of the network.In this case,since gate-ways are selected based on the number of nodes,the Energy Consumption(EC)was high.This paper presents a novel Node Quality-based Clustering Algo-rithm(NQCA)based on Fuzzy-Genetic for Cluster Head and Gateway Selection(FGCHGS).This algorithm combines NQCA with the Improved Weighted Clus-tering Algorithm(IWCA).The NQCA algorithm divides the network into clusters based upon node priority,transmission range,and neighbourfidelity.In addition,the simulation results tend to evaluate the performance effectiveness of the FFFCHGS algorithm in terms of EC,packet loss rate(PLR),etc. 展开更多
关键词 Ad-hoc load balancing H-MANET fuzzy logic system genetic algorithm node quality-based clustering algorithm improved weighted clustering fruitfly optimization
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Identification of High-Risk Scenarios for Cascading Failures in New Energy Power Grids Based on Deep Embedding Clustering Algorithms
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作者 Xueting Cheng Ziqi Zhang +1 位作者 Yueshuang Bao Huiping Zheng 《Energy Engineering》 EI 2023年第11期2517-2529,共13页
At present,the proportion of new energy in the power grid is increasing,and the random fluctuations in power output increase the risk of cascading failures in the power grid.In this paper,we propose a method for ident... At present,the proportion of new energy in the power grid is increasing,and the random fluctuations in power output increase the risk of cascading failures in the power grid.In this paper,we propose a method for identifying high-risk scenarios of interlocking faults in new energy power grids based on a deep embedding clustering(DEC)algorithm and apply it in a risk assessment of cascading failures in different operating scenarios for new energy power grids.First,considering the real-time operation status and system structure of new energy power grids,the scenario cascading failure risk indicator is established.Based on this indicator,the risk of cascading failure is calculated for the scenario set,the scenarios are clustered based on the DEC algorithm,and the scenarios with the highest indicators are selected as the significant risk scenario set.The results of simulations with an example power grid show that our method can effectively identify scenarios with a high risk of cascading failures from a large number of scenarios. 展开更多
关键词 New energy power system deep embedding clustering algorithms cascading failures
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Background dominant colors extraction method based on color image quick fuzzy c-means clustering algorithm 被引量:2
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作者 Zun-yang Liu Feng Ding +1 位作者 Ying Xu Xu Han 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第5期1782-1790,共9页
A quick and accurate extraction of dominant colors of background images is the basis of adaptive camouflage design.This paper proposes a Color Image Quick Fuzzy C-Means(CIQFCM)clustering algorithm based on clustering ... A quick and accurate extraction of dominant colors of background images is the basis of adaptive camouflage design.This paper proposes a Color Image Quick Fuzzy C-Means(CIQFCM)clustering algorithm based on clustering spatial mapping.First,the clustering sample space was mapped from the image pixels to the quantized color space,and several methods were adopted to compress the amount of clustering samples.Then,an improved pedigree clustering algorithm was applied to obtain the initial class centers.Finally,CIQFCM clustering algorithm was used for quick extraction of dominant colors of background image.After theoretical analysis of the effect and efficiency of the CIQFCM algorithm,several experiments were carried out to discuss the selection of proper quantization intervals and to verify the effect and efficiency of the CIQFCM algorithm.The results indicated that the value of quantization intervals should be set to 4,and the proposed algorithm could improve the clustering efficiency while maintaining the clustering effect.In addition,as the image size increased from 128×128 to 1024×1024,the efficiency improvement of CIQFCM algorithm was increased from 6.44 times to 36.42 times,which demonstrated the significant advantage of CIQFCM algorithm in dominant colors extraction of large-size images. 展开更多
关键词 Dominant colors extraction Quick clustering algorithm clustering spatial mapping Background image Camouflage design
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Identification of Convective and Stratiform Clouds Based on the Improved DBSCAN Clustering Algorithm 被引量:2
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作者 Yuanyuan ZUO Zhiqun HU +3 位作者 Shujie YUAN Jiafeng ZHENG Xiaoyan YIN Boyong LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第12期2203-2212,共10页
A convective and stratiform cloud classification method for weather radar is proposed based on the density-based spatial clustering of applications with noise(DBSCAN)algorithm.To identify convective and stratiform clo... A convective and stratiform cloud classification method for weather radar is proposed based on the density-based spatial clustering of applications with noise(DBSCAN)algorithm.To identify convective and stratiform clouds in different developmental phases,two-dimensional(2D)and three-dimensional(3D)models are proposed by applying reflectivity factors at 0.5°and at 0.5°,1.5°,and 2.4°elevation angles,respectively.According to the thresholds of the algorithm,which include echo intensity,the echo top height of 35 dBZ(ET),density threshold,andεneighborhood,cloud clusters can be marked into four types:deep-convective cloud(DCC),shallow-convective cloud(SCC),hybrid convective-stratiform cloud(HCS),and stratiform cloud(SFC)types.Each cloud cluster type is further identified as a core area and boundary area,which can provide more abundant cloud structure information.The algorithm is verified using the volume scan data observed with new-generation S-band weather radars in Nanjing,Xuzhou,and Qingdao.The results show that cloud clusters can be intuitively identified as core and boundary points,which change in area continuously during the process of convective evolution,by the improved DBSCAN algorithm.Therefore,the occurrence and disappearance of convective weather can be estimated in advance by observing the changes of the classification.Because density thresholds are different and multiple elevations are utilized in the 3D model,the identified echo types and areas are dissimilar between the 2D and 3D models.The 3D model identifies larger convective and stratiform clouds than the 2D model.However,the developing convective clouds of small areas at lower heights cannot be identified with the 3D model because they are covered by thick stratiform clouds.In addition,the 3D model can avoid the influence of the melting layer and better suggest convective clouds in the developmental stage. 展开更多
关键词 improved DBSCAN clustering algorithm cloud identification and classification 2D model 3D model weather radar
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Hybridization of Fuzzy and Hard Semi-Supervised Clustering Algorithms Tuned with Ant Lion Optimizer Applied to Higgs Boson Search 被引量:1
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作者 Soukaina Mjahed Khadija Bouzaachane +2 位作者 Ahmad Taher Azar Salah El Hadaj Said Raghay 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第11期459-494,共36页
This paper focuses on the unsupervised detection of the Higgs boson particle using the most informative features and variables which characterize the“Higgs machine learning challenge 2014”data set.This unsupervised ... This paper focuses on the unsupervised detection of the Higgs boson particle using the most informative features and variables which characterize the“Higgs machine learning challenge 2014”data set.This unsupervised detection goes in this paper analysis through 4 steps:(1)selection of the most informative features from the considered data;(2)definition of the number of clusters based on the elbow criterion.The experimental results showed that the optimal number of clusters that group the considered data in an unsupervised manner corresponds to 2 clusters;(3)proposition of a new approach for hybridization of both hard and fuzzy clustering tuned with Ant Lion Optimization(ALO);(4)comparison with some existing metaheuristic optimizations such as Genetic Algorithm(GA)and Particle Swarm Optimization(PSO).By employing a multi-angle analysis based on the cluster validation indices,the confusion matrix,the efficiencies and purities rates,the average cost variation,the computational time and the Sammon mapping visualization,the results highlight the effectiveness of the improved Gustafson-Kessel algorithm optimized withALO(ALOGK)to validate the proposed approach.Even if the paper gives a complete clustering analysis,its novel contribution concerns only the Steps(1)and(3)considered above.The first contribution lies in the method used for Step(1)to select the most informative features and variables.We used the t-Statistic technique to rank them.Afterwards,a feature mapping is applied using Self-Organizing Map(SOM)to identify the level of correlation between them.Then,Particle Swarm Optimization(PSO),a metaheuristic optimization technique,is used to reduce the data set dimension.The second contribution of thiswork concern the third step,where each one of the clustering algorithms as K-means(KM),Global K-means(GlobalKM),Partitioning AroundMedoids(PAM),Fuzzy C-means(FCM),Gustafson-Kessel(GK)and Gath-Geva(GG)is optimized and tuned with ALO. 展开更多
关键词 Ant lion optimization binary clustering clustering algorithms Higgs boson feature extraction dimensionality reduction elbow criterion genetic algorithm particle swarm optimization
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SLID: A Secure Lowest-ID Clustering Algorithm 被引量:1
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作者 HUGuang-ming HUANGZun-guo HUHua-ping GONGZheng-hu 《Wuhan University Journal of Natural Sciences》 CAS 2005年第1期39-42,共4页
In order to solve security problem of clustering algorithm, we proposed amethod to enhance the security of the well-known lowest-ID clustering algorithm. This method isbased on the idea of the secret sharing and the (... In order to solve security problem of clustering algorithm, we proposed amethod to enhance the security of the well-known lowest-ID clustering algorithm. This method isbased on the idea of the secret sharing and the (k, n) threshold cryptography, Each node, whetherclusterhead or ordinary member, holds a share of the global certificate, and any k nodes cancommunicate securely. There is no need for any clusterhead to execute extra functions more thanrouting. Our scheme needs some prior configuration before deployment, and can be used in criticalenvironment with small scale. The security-enhancement for Lowest-ID algorithm can also be appliedinto other clustering approaches with minor modification. The feasibility of this method wasverified bythe simulation results. 展开更多
关键词 clustering algorithm secret sharing threshold cryptography
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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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Research and Application on Spark Clustering Algorithm in Campus Big Data Analysis
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作者 Qing Hou Guangjian Wang +2 位作者 Xiaozheng Wang Jiaxi Xu Yang Xin 《Journal of Computer Science Research》 2020年第1期16-20,共5页
Big data analysis has penetrated into all fields of society and has brought about profound changes.However,there is relatively little research on big data supporting student management regarding college and university... Big data analysis has penetrated into all fields of society and has brought about profound changes.However,there is relatively little research on big data supporting student management regarding college and university’s big data.Taking the student card information as the research sample,using spark big data mining technology and K-Means clustering algorithm,taking scholarship evaluation as an example,the big data is analyzed.Data includes analysis of students’daily behavior from multiple dimensions,and it can prevent the unreasonable scholarship evaluation caused by unfair factors such as plagiarism,votes of teachers and students,etc.At the same time,students’absenteeism,physical health and psychological status in advance can be predicted,which makes student management work more active,accurate and effective. 展开更多
关键词 SPARK clustering algorithm Big data Data analysis Mllib
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Characterization of Vertical Wind Speed Profiles Based on Ward's Agglomerative Clustering Algorithm
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作者 M.C.Bueso A.Molina-García +1 位作者 A.P.Ramallo-González A.Fernández-Guillamón 《Journal of Modern Power Systems and Clean Energy》 SCIE EI CSCD 2023年第5期1437-1449,共13页
Wind turbine blades have been constantly increasing since wind energy becomes a popular renewable energy source to generate electricity. Therefore, the wind sector requires a more efficient and representative characte... Wind turbine blades have been constantly increasing since wind energy becomes a popular renewable energy source to generate electricity. Therefore, the wind sector requires a more efficient and representative characterization of vertical wind speed profiles to assess the potential for a wind power plant site. This paper proposes an alternative characterization of vertical wind speed profiles based on Ward's agglomerative clustering algorithm, including both wind speed module and direction data. This approach gives a more accurate incoming wind speed variation around the rotor swept area, and subsequently, provides a more realistic and complete wind speed vector characterization for vertical profiles. Real wind database collected for 2018 in the Forschungsplattformen in Nordund Ostsee(FINO) research platform is used to assess the methodology. A preliminary pre-processing stage is proposed to select the appropriated number of heights and remove missing or incomplete data. Finally, two locations and four heights are selected, and 561588 wind data are characterized. Results and discussion are also included in this paper. The methodology can be applied to other wind database and locations to characterize vertical wind speed profiles and identify the most likely wind data vector patterns. 展开更多
关键词 clustering algorithm wind speed data management power generation
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Method of neural network modulation recognition based on clustering and Polak-Ribiere algorithm 被引量:4
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作者 Faquan Yang Zan Li +2 位作者 Hongyan Li Haiyan Huang Zhongxian Pan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第5期742-747,共6页
To improve the recognition rate of signal modulation recognition methods based on the clustering algorithm under the low SNR, a modulation recognition method is proposed. The characteristic parameter of the signal is ... To improve the recognition rate of signal modulation recognition methods based on the clustering algorithm under the low SNR, a modulation recognition method is proposed. The characteristic parameter of the signal is extracted by using a clustering algorithm, the neural network is trained by using the algorithm of variable gradient correction (Polak-Ribiere) so as to enhance the rate of convergence, improve the performance of recognition under the low SNR and realize modulation recognition of the signal based on the modulation system of the constellation diagram. Simulation results show that the recognition rate based on this algorithm is enhanced over 30% compared with the methods that adopt clustering algorithm or neural network based on the back propagation algorithm alone under the low SNR. The recognition rate can reach 90% when the SNR is 4 dB, and the method is easy to be achieved so that it has a broad application prospect in the modulating recognition. 展开更多
关键词 clustering algorithm feature extraction algorithm of Polak-Ribiere neural network (NN) modulation recognition.
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Counterexamples to convergence theorem of maximum-entropy clustering algorithm 被引量:6
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作者 于剑 石洪波 +2 位作者 黄厚宽 孙喜晨 程乾生 《Science in China(Series F)》 2003年第5期321-326,共6页
In this paper, we surveyed the development of maximum-entropy clustering algorithm, pointed out that the maximum-entropy clustering algorithm is not new in essence, and constructed two examples to show that the iterat... In this paper, we surveyed the development of maximum-entropy clustering algorithm, pointed out that the maximum-entropy clustering algorithm is not new in essence, and constructed two examples to show that the iterative sequence given by the maximum-entropy clustering algorithm may not converge to a local minimum of its objective function, but a saddle point. Based on these results, our paper shows that the convergence theorem of maximum-entropy clustering algorithm put forward by Kenneth Rose et al. does not hold in general cases. 展开更多
关键词 ENTROPY fixed point clustering algorithm convergence.
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Traffic Clustering Algorithm of Urban Data Brain Based on a Hybrid-Augmented Architecture of Quantum Annealing and Brain-Inspired Cognitive Computing 被引量:3
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作者 Ning Wang Gege Guo +1 位作者 Baonan Wang Chao Wang 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2020年第6期813-825,共13页
In recent years,the urbanization process has brought modernity while also causing key issues,such as traffic congestion and parking conflicts.Therefore,cities need a more intelligent"brain"to form more intel... In recent years,the urbanization process has brought modernity while also causing key issues,such as traffic congestion and parking conflicts.Therefore,cities need a more intelligent"brain"to form more intelligent and efficient transportation systems.At present,as a type of machine learning,the traditional clustering algorithm still has limitations.K-means algorithm is widely used to solve traffic clustering problems,but it has limitations,such as sensitivity to initial points and poor robustness.Therefore,based on the hybrid architecture of Quantum Annealing(QA)and brain-inspired cognitive computing,this study proposes QA and Brain-Inspired Clustering Algorithm(QABICA)to solve the problem of urban taxi-stand locations.Based on the traffic trajectory data of Xi’an and Chengdu provided by Didi Chuxing,the clustering results of our algorithm and K-means algorithm are compared.We find that the average taxi-stand location bias of the final result based on QABICA is smaller than that based on K-means,and the bias of our algorithm can effectively reduce the tradition K-means bias by approximately 42%,up to approximately 83%,with higher robustness.QA algorithm is able to jump out of the local suboptimal solutions and approach the global optimum,and brain-inspired cognitive computing provides search feedback and direction.Thus,we will further consider applying our algorithm to analyze urban traffic flow,and solve traffic congestion and other key problems in intelligent transportation. 展开更多
关键词 cluster analysis intelligent transportation quantum annealing and brain-inspired clustering algorithm K-means
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Quantitative contrast of urban agglomeration colors based on image clustering algorithm:Case study of the Xia-Zhang-Quan metropolitan area 被引量:3
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作者 Meichen Ding 《Frontiers of Architectural Research》 CSCD 2021年第3期692-700,共9页
Color is an important element to consider when shaping urban characteristics.However,previous studies seldom included quantitative analyses of color relationships between urban agglomerations within proximal regions a... Color is an important element to consider when shaping urban characteristics.However,previous studies seldom included quantitative analyses of color relationships between urban agglomerations within proximal regions and with similar cultures to distinguish and shape individual urban personalities.This study focused on Xiamen,Zhangzhou,and Quanzhou metropolitan areas,which are influenced by Minnan culture,and collected natural and cultural landscape network images that collectively represent the urban landscape in China.Color extraction,computer vision processing technologies,and clustering algorithms,such as k-means partitioning,hierarchical methods,and co-occurrence frequency,were applied using image recognition.We then established an urban color database and quantified color attributes.Finally,we conducted a comparative analysis of dominant colors and color combination associations in Xiamen,Zhangzhou,and Quanzhou metropolitan areas to explore their similarities and differences and define their characteristics.We also considered other cities of the same type for comparison. 展开更多
关键词 City color Urban agglomeration Network image clustering algorithm Computer vision
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Energy Efficient Backoff Hierarchical Clustering Algorithms for Multi-Hop Wireless Sensor Networks 被引量:2
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作者 王珺 曹涌涛 +1 位作者 谢俊元 陈世福 《Journal of Computer Science & Technology》 SCIE EI CSCD 2011年第2期283-291,共9页
Compared with flat routing protocols, clustering is a fundamental performance improvement technique in wireless sensor networks, which can increase network scalability and lifetime. In this paper, we integrate the mul... Compared with flat routing protocols, clustering is a fundamental performance improvement technique in wireless sensor networks, which can increase network scalability and lifetime. In this paper, we integrate the multi-hop technique with a backoff-based clustering algorithm to organize sensors. By using an adaptive backoff strategy, the algorithm not only realizes load balance among sensor node, but also achieves fairly uniform cluster head distribution across the network. Simulation results also demonstrate our algorithm is more energy-efficient than classical ones. Our algorithm is also easily extended to generate a hierarchy of cluster heads to obtain better network management and energy-efficiency. 展开更多
关键词 multi-hop wireless sensor network clustering algorithm backoff strategy
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Cancellation of nonlinear distortion based on integration of FCM clustering algorithm and adaptive-two-stage linear approximation 被引量:1
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作者 WANG Gui-ye ZOU Wei-xia +2 位作者 WANG Zhen-yu DU Guang-long GAO Ying 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2014年第3期18-22,共5页
A hybrid system of the fuzzy c-means (FCM) clustering algorithm and adaptive-two-stage linear approximation was presented for nonlinear distortion cancellation of radio frequency (RF) power amplifier (PA). This ... A hybrid system of the fuzzy c-means (FCM) clustering algorithm and adaptive-two-stage linear approximation was presented for nonlinear distortion cancellation of radio frequency (RF) power amplifier (PA). This mechanism can effectively eliminate noise, adaptively model PA's instantaneous change, and efficiently correct nonlinear distortion. This article puts forward the FCM clustering algorithm for clustering received signals to eliminate white noise, and then uses the adaptive-two-stage linear approximation to fit the inverse function of the amplitude's and phase's nonlinear mapping during the training phase. Parameters of the linear function and similarity function are trained using the gradient-descent and minimum mean-square error criteria. The proposed approach's training results is directly employed to eliminate sampling signal's nonlinear distortion. This hybrid method is realized easier than the multi-segment linear approximation and could reduce the received signal's bit error rate (BER) more efficiently. 展开更多
关键词 PA nonlinear distortion cancellation FCM clustering algorithm similarity function adaptive-two-stage linear approximation
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Improved Kernel Possibilistic Fuzzy Clustering Algorithm Based on Invasive Weed Optimization 被引量:1
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作者 赵小强 周金虎 《Journal of Shanghai Jiaotong university(Science)》 EI 2015年第2期164-170,共7页
Fuzzy c-means(FCM) clustering algorithm is sensitive to noise points and outlier data, and the possibilistic fuzzy c-means(PFCM) clustering algorithm overcomes the problem well, but PFCM clustering algorithm has some ... Fuzzy c-means(FCM) clustering algorithm is sensitive to noise points and outlier data, and the possibilistic fuzzy c-means(PFCM) clustering algorithm overcomes the problem well, but PFCM clustering algorithm has some problems: it is still sensitive to initial clustering centers and the clustering results are not good when the tested datasets with noise are very unequal. An improved kernel possibilistic fuzzy c-means algorithm based on invasive weed optimization(IWO-KPFCM) is proposed in this paper. This algorithm first uses invasive weed optimization(IWO) algorithm to seek the optimal solution as the initial clustering centers, and introduces kernel method to make the input data from the sample space map into the high-dimensional feature space. Then, the sample variance is introduced in the objection function to measure the compact degree of data. Finally, the improved algorithm is used to cluster data. The simulation results of the University of California-Irvine(UCI) data sets and artificial data sets show that the proposed algorithm has stronger ability to resist noise, higher cluster accuracy and faster convergence speed than the PFCM algorithm. 展开更多
关键词 data mining clustering algorithm possibilistic fuzzy c-means(PFCM) kernel possibilistic fuzzy c-means algorithm based on invasiv
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Application of U-Net and Optimized Clustering in Medical Image Segmentation:A Review 被引量:1
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作者 Jiaqi Shao Shuwen Chen +3 位作者 Jin Zhou Huisheng Zhu Ziyi Wang Mackenzie Brown 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第9期2173-2219,共47页
As a mainstream research direction in the field of image segmentation,medical image segmentation plays a key role in the quantification of lesions,three-dimensional reconstruction,region of interest extraction and so ... As a mainstream research direction in the field of image segmentation,medical image segmentation plays a key role in the quantification of lesions,three-dimensional reconstruction,region of interest extraction and so on.Compared with natural images,medical images have a variety of modes.Besides,the emphasis of information which is conveyed by images of different modes is quite different.Because it is time-consuming and inefficient to manually segment medical images only by professional and experienced doctors.Therefore,large quantities of automated medical image segmentation methods have been developed.However,until now,researchers have not developed a universal method for all types of medical image segmentation.This paper reviews the literature on segmentation techniques that have produced major breakthroughs in recent years.Among the large quantities of medical image segmentation methods,this paper mainly discusses two categories of medical image segmentation methods.One is the improved strategies based on traditional clustering method.The other is the research progress of the improved image segmentation network structure model based on U-Net.The power of technology proves that the performance of the deep learning-based method is significantly better than that of the traditional method.This paper discussed both advantages and disadvantages of different algorithms and detailed how these methods can be used for the segmentation of lesions or other organs and tissues,as well as possible technical trends for future work. 展开更多
关键词 Medical image segmentation clustering algorithm U-Net
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An Improved Weighted Clustering Algorithm in MANET
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作者 WANGJin XULi ZHENGBao-yu 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2004年第4期20-25,共6页
The original clustering algorithms in Mobile Ad hoc Network(MANET)are firstly analyzed in this paper.Based on which,an Improved Weighted Clustering Algorithm(IWCA)is proposed.Then,the principle and steps of ouralgorit... The original clustering algorithms in Mobile Ad hoc Network(MANET)are firstly analyzed in this paper.Based on which,an Improved Weighted Clustering Algorithm(IWCA)is proposed.Then,the principle and steps of ouralgorithm are explained in detail,and a comparison is made between the original algorithms and our improved method inthe aspects of average cluster number,topology stability,clusterhead load balance and network lifetime.The experimentalresults show that our improved algorithm has the best performance on average. 展开更多
关键词 MANET clustering algorithm load balancing network lifetime
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Study of degradation of fuel cell stack based on the collected high-dimensional data and clustering algorithms calculations
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作者 Tong Niu Weifeng Huang +4 位作者 Caizhi Zhang Tao Zeng Jiawei Chen Yu Li Yang Liu 《Energy and AI》 2022年第4期29-40,共12页
Accurate perception of the performance degradation of fuel cell is very important to detect its health state.However,inconsistent operating conditions of fuel cell vehicles in the test result in errors in the data.In ... Accurate perception of the performance degradation of fuel cell is very important to detect its health state.However,inconsistent operating conditions of fuel cell vehicles in the test result in errors in the data.In order to obtain a more credible degradation rate,this study proposes a novel method to classify the experimental data collected under different working conditions into similar operating conditions by using dimensionality reduction and clustering algorithms.Firstly,the experimental data collected from fuel cell vehicles belong to high-dimensional data.Then projecting high-dimensional data into three-dimensional feature vector space via principal component analysis(PCA).The dimension-reduced three-dimensional feature vectors are input into the clustering algorithm,such as K-means and density-based noise application spatial clustering(DBSCAN).According to the clustering results,the fuel cell voltage data with similar operating conditions can be classified.Finally,the selected voltage data can be used to precisely represent the true performance degradation of an on-board fuel cell stack.The results show that the voltage using the K-means algorithm declines the fastest,followed by the DBSCAN algorithm, finally the original data, which indicates that the performance of the fuel cell actually declines faste. Early intervention can prolong its life to the greatest extent. 展开更多
关键词 Fuel cell vehicle Principal component analysis clustering algorithms Degradation of fuel cell
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A Clustering Method Based on Brain Storm Optimization Algorithm
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作者 Tianyu Wang Yu Xue +3 位作者 Yan Zhao Yuxiang Wang Yan Zhang Yuxiang He 《Journal of Information Hiding and Privacy Protection》 2020年第3期135-142,共8页
In the field of data mining and machine learning,clustering is a typical issue which has been widely studied by many researchers,and lots of effective algorithms have been proposed,including K-means,fuzzy c-means(FCM)... In the field of data mining and machine learning,clustering is a typical issue which has been widely studied by many researchers,and lots of effective algorithms have been proposed,including K-means,fuzzy c-means(FCM)and DBSCAN.However,the traditional clustering methods are easily trapped into local optimum.Thus,many evolutionary-based clustering methods have been investigated.Considering the effectiveness of brain storm optimization(BSO)in increasing the diversity while the diversity optimization is performed,in this paper,we propose a new clustering model based on BSO to use the global ability of BSO.In our experiment,we apply the novel binary model to solve the problem.During the period of processing data,BSO was mainly utilized for iteration.Also,in the process of K-means,we set the more appropriate parameters selected to match it greatly.Four datasets were used in our experiment.In our model,BSO was first introduced in solving the clustering problem.With the algorithm running on each dataset repeatedly,our experimental results have obtained good convergence and diversity.In addition,by comparing the results with other clustering models,the BSO clustering model also guarantees high accuracy.Therefore,from many aspects,the simulation results show that the model of this paper has good performance. 展开更多
关键词 clustering method brain storm optimization algorithm(BSO) evolutionary clustering algorithm data mining
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