期刊文献+
共找到55,307篇文章
< 1 2 250 >
每页显示 20 50 100
Energy Efficient Clustering and Sink Mobility Protocol Using Hybrid Golden Jackal and Improved Whale Optimization Algorithm for Improving Network Longevity in WSNs
1
作者 S B Lenin R Sugumar +2 位作者 J S Adeline Johnsana N Tamilarasan R Nathiya 《China Communications》 2025年第3期16-35,共20页
Reliable Cluster Head(CH)selectionbased routing protocols are necessary for increasing the packet transmission efficiency with optimal path discovery that never introduces degradation over the transmission reliability... Reliable Cluster Head(CH)selectionbased routing protocols are necessary for increasing the packet transmission efficiency with optimal path discovery that never introduces degradation over the transmission reliability.In this paper,Hybrid Golden Jackal,and Improved Whale Optimization Algorithm(HGJIWOA)is proposed as an effective and optimal routing protocol that guarantees efficient routing of data packets in the established between the CHs and the movable sink.This HGJIWOA included the phases of Dynamic Lens-Imaging Learning Strategy and Novel Update Rules for determining the reliable route essential for data packets broadcasting attained through fitness measure estimation-based CH selection.The process of CH selection achieved using Golden Jackal Optimization Algorithm(GJOA)completely depends on the factors of maintainability,consistency,trust,delay,and energy.The adopted GJOA algorithm play a dominant role in determining the optimal path of routing depending on the parameter of reduced delay and minimal distance.It further utilized Improved Whale Optimisation Algorithm(IWOA)for forwarding the data from chosen CHs to the BS via optimized route depending on the parameters of energy and distance.It also included a reliable route maintenance process that aids in deciding the selected route through which data need to be transmitted or re-routed.The simulation outcomes of the proposed HGJIWOA mechanism with different sensor nodes confirmed an improved mean throughput of 18.21%,sustained residual energy of 19.64%with minimized end-to-end delay of 21.82%,better than the competitive CH selection approaches. 展开更多
关键词 cluster Heads(CHs) Golden Jackal Optimization Algorithm(GJOA) Improved Whale Optimization Algorithm(IWOA) unequal clustering
在线阅读 下载PDF
Data Gathering Based on Hybrid Energy Efficient Clustering Algorithm and DCRNN Model in Wireless Sensor Network
2
作者 Li Cuiran Liu Shuqi +1 位作者 Xie Jianli Liu Li 《China Communications》 2025年第3期115-131,共17页
In order to solve the problems of short network lifetime and high data transmission delay in data gathering for wireless sensor network(WSN)caused by uneven energy consumption among nodes,a hybrid energy efficient clu... In order to solve the problems of short network lifetime and high data transmission delay in data gathering for wireless sensor network(WSN)caused by uneven energy consumption among nodes,a hybrid energy efficient clustering routing base on firefly and pigeon-inspired algorithm(FF-PIA)is proposed to optimise the data transmission path.After having obtained the optimal number of cluster head node(CH),its result might be taken as the basis of producing the initial population of FF-PIA algorithm.The L′evy flight mechanism and adaptive inertia weighting are employed in the algorithm iteration to balance the contradiction between the global search and the local search.Moreover,a Gaussian perturbation strategy is applied to update the optimal solution,ensuring the algorithm can jump out of the local optimal solution.And,in the WSN data gathering,a onedimensional signal reconstruction algorithm model is developed by dilated convolution and residual neural networks(DCRNN).We conducted experiments on the National Oceanic and Atmospheric Administration(NOAA)dataset.It shows that the DCRNN modeldriven data reconstruction algorithm improves the reconstruction accuracy as well as the reconstruction time performance.FF-PIA and DCRNN clustering routing co-simulation reveals that the proposed algorithm can effectively improve the performance in extending the network lifetime and reducing data transmission delay. 展开更多
关键词 clustering data gathering DCRNN model network lifetime wireless sensor network
在线阅读 下载PDF
ALLIED FUZZY c-MEANS CLUSTERING MODEL 被引量:2
3
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
在线阅读 下载PDF
基于Blending-Clustering集成学习的大坝变形预测模型
4
作者 冯子强 李登华 丁勇 《水利水电技术(中英文)》 北大核心 2024年第4期59-70,共12页
【目的】变形是反映大坝结构性态最直观的效应量,构建科学合理的变形预测模型是保障大坝安全健康运行的重要手段。针对传统大坝变形预测模型预测精度低、误报率高等问题导致的错误报警现象,【方法】选取不同预测模型和聚类算法集成,构... 【目的】变形是反映大坝结构性态最直观的效应量,构建科学合理的变形预测模型是保障大坝安全健康运行的重要手段。针对传统大坝变形预测模型预测精度低、误报率高等问题导致的错误报警现象,【方法】选取不同预测模型和聚类算法集成,构建了一种Blending-Clustering集成学习的大坝变形预测模型,该模型以Blending对单一预测模型集成提升预测精度为核心,并通过Clustering聚类优选预测值改善模型稳定性。以新疆某面板堆石坝变形监测数据为实例分析,通过多模型预测性能比较,对所提出模型的预测精度和稳定性进行全面评估。【结果】结果显示:Blending-Clustering模型将预测模型和聚类算法集成,均方根误差(RMSE)和归一化平均百分比误差(nMAPE)明显降低,模型的预测精度得到显著提高;回归相关系数(R~2)得到提升,模型具备更强的拟合能力;在面板堆石坝上22个测点变形数据集上的预测评价指标波动范围更小,模型的泛化性和稳定性得到有效增强。【结论】结果表明:Blending-Clustering集成预测模型对于预测精度、泛化性和稳定性均有明显提升,在实际工程具有一定的应用价值。 展开更多
关键词 大坝 变形 预测模型 Blending集成 clustering集成 模型融合
在线阅读 下载PDF
Radio-map Establishment based on Fuzzy Clustering for WLAN Hybrid KNN/ANN Indoor Positioning 被引量:9
5
作者 Zhou Mu Xu Yubin Ma Lin 《China Communications》 SCIE CSCD 2010年第3期64-80,共17页
A novel radio-map establishment based on fuzzy clustering for hybrid K-Nearest Neighbor (KNN) and Artifi cial Neural Network (ANN) position algorithm in WLAN indoor environment is proposed. First of all, the Principal... A novel radio-map establishment based on fuzzy clustering for hybrid K-Nearest Neighbor (KNN) and Artifi cial Neural Network (ANN) position algorithm in WLAN indoor environment is proposed. First of all, the Principal Component Analysis (PCA) is utilized for the purpose of simplifying input dimensions of position estimation algorithm and saving storage cost for the establishment of radio-map. Then, reference points (RPs) calibrated in the off-line phase are divided into separate clusters by Fuzzy C-means clustering (FCM), and membership degrees (MDs) for different clusters are also allocated to each RPs. However, the singular RPs cased by the multi-path effect signifi cantly decreases the clustering performance. Therefore, a novel radio-map establishment method is presented based on the modifi cation of signal samples recorded at singular RPs by surface fitting. In the on-line phase, the region which the mobile terminal (MT) belongs to is estimated according to the MDs firstly. Then, in estimated small dimensional regions, MT's coordinates are calculated byKNN positioning method for efficiency purpose. However, for the regions including singular RPs, ANN method is utilized because ofits great pattern matching ability. Furthermore, compared with other typical indoor positioning methods, feasibility and effectiveness of this hybrid KNN/ANN method are also verified by the experimental results in static and tracking situations. 展开更多
关键词 WLAN indoor location fuzzy clustering principal component artificial neural network radio-map
在线阅读 下载PDF
Unknown Application Layer Protocol Recognition Method Based on Deep Clustering 被引量:1
6
作者 Wu Jisheng Hong Zheng +1 位作者 Ma Tiantian Si Jianpeng 《China Communications》 SCIE CSCD 2024年第12期275-296,共22页
In recent years,many unknown protocols are constantly emerging,and they bring severe challenges to network security and network management.Existing unknown protocol recognition methods suffer from weak feature extract... In recent years,many unknown protocols are constantly emerging,and they bring severe challenges to network security and network management.Existing unknown protocol recognition methods suffer from weak feature extraction ability,and they cannot mine the discriminating features of the protocol data thoroughly.To address the issue,we propose an unknown application layer protocol recognition method based on deep clustering.Deep clustering which consists of the deep neural network and the clustering algorithm can automatically extract the features of the input and cluster the data based on the extracted features.Compared with the traditional clustering methods,deep clustering boasts of higher clustering accuracy.The proposed method utilizes network-in-network(NIN),channel attention,spatial attention and Bidirectional Long Short-term memory(BLSTM)to construct an autoencoder to extract the spatial-temporal features of the protocol data,and utilizes the unsupervised clustering algorithm to recognize the unknown protocols based on the features.The method firstly extracts the application layer protocol data from the network traffic and transforms the data into one-dimensional matrix.Secondly,the autoencoder is pretrained,and the protocol data is compressed into low dimensional latent space by the autoencoder and the initial clustering is performed with K-Means.Finally,the clustering loss is calculated and the classification model is optimized according to the clustering loss.The classification results can be obtained when the classification model is optimal.Compared with the existing unknown protocol recognition methods,the proposed method utilizes deep clustering to cluster the unknown protocols,and it can mine the key features of the protocol data and recognize the unknown protocols accurately.Experimental results show that the proposed method can effectively recognize the unknown protocols,and its performance is better than other methods. 展开更多
关键词 attention mechanism clustering loss deep clustering network traffic unknown protocol recognition
在线阅读 下载PDF
A fast and effective fuzzy clustering algorithm for color image segmentation 被引量:4
7
作者 王改华 李德华 《Journal of Beijing Institute of Technology》 EI CAS 2012年第4期518-525,共8页
A fast and effective fuzzy clustering algorithm is proposed. The algorithm splits an image into n × n blocks, and uses block variance to judge whether the block region is homogeneous. Mean and center pixel of eac... A fast and effective fuzzy clustering algorithm is proposed. The algorithm splits an image into n × n blocks, and uses block variance to judge whether the block region is homogeneous. Mean and center pixel of each homogeneous block are extracted for feature. Each inhomogeneous block is split into separate pixels and the mean of neighboring pixels within a window around each pixel and pixel value are extracted for feature. Then cluster of homogeneous blocks and cluster of separate pixels from inhomogeneous blocks are carried out respectively according to different membership functions. In fuzzy clustering stage, the center pixel and center number of the initial clustering are calculated based on histogram by using mean feature. Then different membership functions according to comparative result of block variance are computed. Finally, modified fuzzy c-means with spatial information to complete image segmentation axe used. Experimental results show that the proposed method can achieve better segmental results and has shorter executive time than many well-known methods. 展开更多
关键词 cluster image segmentation fuzzy c-means HISTOGRAM
在线阅读 下载PDF
Location of Electric Vehicle Charging Station Based on Spatial Clustering and Multi-hierarchical Fuzzy Evaluation 被引量:2
8
作者 Wang Meng Liu Kai 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第1期89-96,共8页
For the charging station construction of electric vehicle,location selecting is a key issue.There are two problems in location selection of the electric vehicle charging station.One is determining the location of char... For the charging station construction of electric vehicle,location selecting is a key issue.There are two problems in location selection of the electric vehicle charging station.One is determining the location of charging station;the other is evaluating the location of charging station.To determine the charging station location,an spatial clustering algorithm is proposed and programmed.The example simulation shows the effectiveness of the spatial clustering algorithm.To evaluate the charging station location,a multi-hierarchical fuzzy method is proposed.Based on the location factors of electric vehicle charging station,the hierarchical evaluation structure of electric vehicle charging station location is constructed,including three levels,4first-class factors and 14second-class factors.The fuzzy multi-hierarchical evaluation model and algorithm are built.The analysis results show that the multi-hierarchical fuzzy method can reasonably complete the electric vehicle charging station location evaluation. 展开更多
关键词 electric vehicle CHARGING STATION spatial clustering multi-hierarchical fuzzy evaluation
在线阅读 下载PDF
CSFW-SC: Cuckoo Search Fuzzy-Weighting Algorithm for Subspace Clustering Applying to High-Dimensional Clustering 被引量:1
9
作者 WANG Jindong HE Jiajing +1 位作者 ZHANG Hengwei YU Zhiyong 《China Communications》 SCIE CSCD 2015年第S2期55-63,共9页
Aimed at the issue that traditional clustering methods are not appropriate to high-dimensional data, a cuckoo search fuzzy-weighting algorithm for subspace clustering is presented on the basis of the exited soft subsp... Aimed at the issue that traditional clustering methods are not appropriate to high-dimensional data, a cuckoo search fuzzy-weighting algorithm for subspace clustering is presented on the basis of the exited soft subspace clustering algorithm. In the proposed algorithm, a novel objective function is firstly designed by considering the fuzzy weighting within-cluster compactness and the between-cluster separation, and loosening the constraints of dimension weight matrix. Then gradual membership and improved Cuckoo search, a global search strategy, are introduced to optimize the objective function and search subspace clusters, giving novel learning rules for clustering. At last, the performance of the proposed algorithm on the clustering analysis of various low and high dimensional datasets is experimentally compared with that of several competitive subspace clustering algorithms. Experimental studies demonstrate that the proposed algorithm can obtain better performance than most of the existing soft subspace clustering algorithms. 展开更多
关键词 HIGH-DIMENSIONAL data clustering soft SUBSPACE CUCKOO SEARCH fuzzy clustering
在线阅读 下载PDF
An air combat maneuver pattern extraction based on time series segmentation and clustering analysis
10
作者 Zhifei Xi Yingxin Kou +2 位作者 Zhanwu Li Yue Lv You Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第6期149-162,共14页
Target maneuver recognition is a prerequisite for air combat situation awareness,trajectory prediction,threat assessment and maneuver decision.To get rid of the dependence of the current target maneuver recognition me... Target maneuver recognition is a prerequisite for air combat situation awareness,trajectory prediction,threat assessment and maneuver decision.To get rid of the dependence of the current target maneuver recognition method on empirical criteria and sample data,and automatically and adaptively complete the task of extracting the target maneuver pattern,in this paper,an air combat maneuver pattern extraction based on time series segmentation and clustering analysis is proposed by combining autoencoder,G-G clustering algorithm and the selective ensemble clustering analysis algorithm.Firstly,the autoencoder is used to extract key features of maneuvering trajectory to remove the impacts of redundant variables and reduce the data dimension;Then,taking the time information into account,the segmentation of Maneuver characteristic time series is realized with the improved FSTS-AEGG algorithm,and a large number of maneuver primitives are extracted;Finally,the maneuver primitives are grouped into some categories by using the selective ensemble multiple time series clustering algorithm,which can prove that each class represents a maneuver action.The maneuver pattern extraction method is applied to small scale air combat trajectory and can recognize and correctly partition at least 71.3%of maneuver actions,indicating that the method is effective and satisfies the requirements for engineering accuracy.In addition,this method can provide data support for various target maneuvering recognition methods proposed in the literature,greatly reduce the workload and improve the recognition accuracy. 展开更多
关键词 Maneuver pattern extraction Data mining fuzzy segmentation Selective ensemble clustering
在线阅读 下载PDF
Optimized Fuzzy Clustering Method for Health Monitoring of Shield Tunnels 被引量:3
11
作者 周发 张巍 +2 位作者 孙可 唐心煜 王小敏 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2015年第3期325-333,共9页
Since health monitoring of shield tunnels generally employs multiple sensors belonging to different types,a fine analysis on massive monitoring data,as well as further quantitative health grading,is really challenging... Since health monitoring of shield tunnels generally employs multiple sensors belonging to different types,a fine analysis on massive monitoring data,as well as further quantitative health grading,is really challenging.An optimized fuzzy clustering analysis method based on the fuzzy equivalence relation is proposed for health monitoring of shield tunnels.Clustering results are auto-generated by using fuzzy similarity-valued map.The results follow the idea of unsupervised classification.Moreover,a convenient new health index HI is proposed for a fast tunnel-health grading.A case study on Nanjing Yangtze River Tunnel is presented to validate this method.Three types of indicators,namely soil pressure,pore water pressure and steel strain,are used to develop the clustering model.The clustering results are verified by analyzing the engineering geological conditions;the validity and the efficacy of the proposed method are also demonstrated.Further,the fuzzy clustering analysis also represents a potential for identifying abnormal monitoring data.This investigation indicates the fuzzy clustering analysis method is capable of characterizing the fuzziness of tunnel health,and beneficial to clarify the tunnel health evaluation uncertainties. 展开更多
关键词 SHIELD TUNNEL HEALTH MONITORING optimized fuzzy CL
在线阅读 下载PDF
SOFT IMAGE SEGMENTATION BASED ON CENTER-FREE FUZZY CLUSTERING 被引量:2
12
作者 马儒宁 朱燕 丁军娣 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2013年第1期67-76,共10页
Image segmentation remains one of the major challenges in image analysis.And soft image segmentation has been widely used due to its good effect.Fuzzy clustering algorithms are very popular in soft segmentation.A new ... Image segmentation remains one of the major challenges in image analysis.And soft image segmentation has been widely used due to its good effect.Fuzzy clustering algorithms are very popular in soft segmentation.A new soft image segmentation method based on center-free fuzzy clustering is proposed.The center-free fuzzy clustering is the modified version of the classical fuzzy C-means ( FCM ) clustering.Different from traditional fuzzy clustering , the center-free fuzzy clustering does not need to calculate the cluster center , so it can be applied to pairwise relational data.In the proposed method , the mean-shift method is chosen for initial segmentation firstly , then the center-free clustering is used to merge regions and the final segmented images are obtained at last.Experimental results show that the proposed method is better than other image segmentation methods based on traditional clustering. 展开更多
关键词 soft image segmentationl fuzzy clusteringl center-free clusteringI region merging
在线阅读 下载PDF
Background dominant colors extraction method based on color image quick fuzzy c-means clustering algorithm 被引量:2
13
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
在线阅读 下载PDF
Design and construction of charged-particle telescope array for study of exotic nuclear clustering structure
14
作者 Zheng‑Li Liao Xi‑Guang Cao +2 位作者 Yu‑Xuan Yang Chang‑Bo Fu Xian‑Gai Deng 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第8期114-123,共10页
The exploration of exotic shapes and properties of atomic nuclei,e.g.,αcluster and toroidal shape,is a fascinating field in nuclear physics.To study the decay of these nuclei,a novel detector aimed at detecting multi... The exploration of exotic shapes and properties of atomic nuclei,e.g.,αcluster and toroidal shape,is a fascinating field in nuclear physics.To study the decay of these nuclei,a novel detector aimed at detecting multipleα-particle events was designed and constructed.The detector comprises two layers of double-sided silicon strip detectors(DSSD)and a cesium iodide scintillator array coupled with silicon photomultipliers array as light sensors,which has the advantages of their small size,fast response,and large dynamic range.DSSDs coupled with cesium iodide crystal arrays are used to distinguish multipleαhits.The detector array has a compact and integrated design that can be adapted to different experimental conditions.The detector array was simulated using Geant4,and the excitation energy spectra of someα-clustering nuclei were reconstructed to demonstrate the performance.The simulation results show that the detector array has excellent angular and energy resolutions,enabling effective reconstruction of the nuclear excited state by multipleαparticle events.This detector offers a new and powerful tool for nuclear physics experiments and has the potential to discover interesting physical phenomena related to exotic nuclear structures and their decay mechanisms. 展开更多
关键词 cluster decay Toroidal structure Telescope array SIPM Energy resolution
在线阅读 下载PDF
Fuzzy Based Adaptive Clustering to Improve the Lifetime of Wireless Sensor Network 被引量:1
15
作者 D.Uma Maheswari S.Sudha M.Meenalochani 《China Communications》 SCIE CSCD 2019年第12期56-71,共16页
The objective of the recently proposed fuzzy based hierarchical routing protocol F-SCH is to improve the lifetime of a Wireless Sensor Network. Though the performance of F-SCH is better than LEACH, the randomness in C... The objective of the recently proposed fuzzy based hierarchical routing protocol F-SCH is to improve the lifetime of a Wireless Sensor Network. Though the performance of F-SCH is better than LEACH, the randomness in CH selection inhibits it from attaining enhanced lifetime. CBCH ensures maximum network lifetime when CH is close to the centroid of the cluster. However, for a widely distributed network, CBCH results in small sized clusters increasing the inter cluster communication cost. Hence, with an objective to enhance the network lifetime, a fuzzy based two-level hierarchical routing protocol is proposed. The novelty of the proposal lies in identification of appropriate parameters used in Cluster Head and Super Cluster Head selection. Experiments for different network scenarios are performed through both simulation and hardware to validate the proposal. The performance of the network is evaluated in terms of Node Death. The proposal is compared with F-SCH and the results reveal the efficacy of the proposal in enhancing the lifetime of network. 展开更多
关键词 hierarchical routing node degree CENTRALITY network lifetime fuzzy wireless sensor networks
在线阅读 下载PDF
Deep Reinforcement Learning Based Joint Cooperation Clustering and Downlink Power Control for Cell-Free Massive MIMO
16
作者 Du Mingjun Sun Xinghua +2 位作者 Zhang Yue Wang Junyuan Liu Pei 《China Communications》 SCIE CSCD 2024年第11期1-14,共14页
In recent times,various power control and clustering approaches have been proposed to enhance overall performance for cell-free massive multipleinput multiple-output(CF-mMIMO)networks.With the emergence of deep reinfo... In recent times,various power control and clustering approaches have been proposed to enhance overall performance for cell-free massive multipleinput multiple-output(CF-mMIMO)networks.With the emergence of deep reinforcement learning(DRL),significant progress has been made in the field of network optimization as DRL holds great promise for improving network performance and efficiency.In this work,our focus delves into the intricate challenge of joint cooperation clustering and downlink power control within CF-mMIMO networks.Leveraging the potent deep deterministic policy gradient(DDPG)algorithm,our objective is to maximize the proportional fairness(PF)for user rates,thereby aiming to achieve optimal network performance and resource utilization.Moreover,we harness the concept of“divide and conquer”strategy,introducing two innovative methods termed alternating DDPG(A-DDPG)and hierarchical DDPG(H-DDPG).These approaches aim to decompose the intricate joint optimization problem into more manageable sub-problems,thereby facilitating a more efficient resolution process.Our findings unequivo-cally showcase the superior efficacy of our proposed DDPG approach over the baseline schemes in both clustering and downlink power control.Furthermore,the A-DDPG and H-DDPG obtain higher performance gain than DDPG with lower computational complexity. 展开更多
关键词 cell-free massive MIMO clustering deep reinforcement learning power control
在线阅读 下载PDF
Clustering in nuclei:progress and perspectives
17
作者 Kang Wei Yan‑Lin Ye Zai‑Hong Yang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第12期343-375,共33页
Nucleus is essentially composed of protons and neutrons,which are commonly known as nucleons.Interestingly,some of nucleons may group together and exhibit collective behavior inside a nucleus.Such clustering efects ha... Nucleus is essentially composed of protons and neutrons,which are commonly known as nucleons.Interestingly,some of nucleons may group together and exhibit collective behavior inside a nucleus.Such clustering efects have been known since the early stages of nuclear physics because of the observation and description ofα-cluster decay from many heavy nuclei.Subsequent studies demonstrated that cluster structures exist in many nuclear systems,especially in weakly bound or excited states,and are complementary to the shell-like structures.In this review article,we provide a brief historical recall of the feld,and follow it with a conceptual and logical description of the major theoretical models that have been frequently applied in the literature to describe nuclear clustering.Experimental methods and progress are outlined,recent outcomes are emphasized,and perspectives relevant to future studies of heavy neutron-rich systems are discussed. 展开更多
关键词 Nuclear matter cluster structure Wave-packet presentation Molecular bond Condensation confguration
在线阅读 下载PDF
基于Fuzzy-DEMATEL-ISM的新能源汽车供应链韧性影响因素研究
18
作者 孙静 陈雨朵 《物流技术》 2025年第1期37-48,共12页
全球化和产业革命推动下,新能源汽车供应链面临潜在风险与挑战,提升供应链韧性对保障产业稳定和可持续发展至关重要。现有研究多侧重于提升路径、韧性测量和宏观政策,缺乏对影响因素系统性和层次性的研究。全面分析新能源汽车供应链韧... 全球化和产业革命推动下,新能源汽车供应链面临潜在风险与挑战,提升供应链韧性对保障产业稳定和可持续发展至关重要。现有研究多侧重于提升路径、韧性测量和宏观政策,缺乏对影响因素系统性和层次性的研究。全面分析新能源汽车供应链韧性的影响因素,识别关键因素,并剖析这些因素间的逻辑关系和层次结构,可为提升供应链韧性提供理论依据和实践指导。首先,通过文献分析法构建初步影响因素体系,并邀请专家对影响因素进行调查和筛选,从预测能力、响应能力、恢复能力、学习能力和可持续发展能力5个维度构建了包含20个影响因素的指标体系。然后,运用FuzzyDEMATEL模型识别关键影响因素,并通过ISM模型分析影响因素间的逻辑关系和层次结构。研究发现供应链数字化水平、智慧物流水平和供应链合作等8个因素为新能源汽车供应链韧性的关键影响因素,供应链可见性和财务实力是供应链韧性的根本因素,可持续发展能力对供应链韧性起最直接作用。基于研究结果,提出加强供应链数智化转型、深化供应链合作、构建ESG生态体系等建议,以提升新能源汽车供应链韧性。 展开更多
关键词 新能源汽车 供应链韧性 影响因素 fuzzy-DEMATEL-ISM
在线阅读 下载PDF
Using genetic algorithm based fuzzy adaptive resonance theory for clustering analysis 被引量:3
19
作者 LIU Bo WANG Yong WANG Hong-jian 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2006年第B07期547-551,共5页
关键词 聚类分析 遗传算法 模糊自适应谐振理论 人工神经网络
在线阅读 下载PDF
Hybrid Seagull and Whale Optimization Algorithm-Based Dynamic Clustering Protocol for Improving Network Longevity in Wireless Sensor Networks
20
作者 P.Vinoth Kumar K.Venkatesh 《China Communications》 SCIE CSCD 2024年第10期113-131,共19页
Energy efficiency is the prime concern in Wireless Sensor Networks(WSNs) as maximized energy consumption without essentially limits the energy stability and network lifetime. Clustering is the significant approach ess... Energy efficiency is the prime concern in Wireless Sensor Networks(WSNs) as maximized energy consumption without essentially limits the energy stability and network lifetime. Clustering is the significant approach essential for minimizing unnecessary transmission energy consumption with sustained network lifetime. This clustering process is identified as the Non-deterministic Polynomial(NP)-hard optimization problems which has the maximized probability of being solved through metaheuristic algorithms.This adoption of hybrid metaheuristic algorithm concentrates on the identification of the optimal or nearoptimal solutions which aids in better energy stability during Cluster Head(CH) selection. In this paper,Hybrid Seagull and Whale Optimization Algorithmbased Dynamic Clustering Protocol(HSWOA-DCP)is proposed with the exploitation benefits of WOA and exploration merits of SEOA to optimal CH selection for maintaining energy stability with prolonged network lifetime. This HSWOA-DCP adopted the modified version of SEagull Optimization Algorithm(SEOA) to handle the problem of premature convergence and computational accuracy which is maximally possible during CH selection. The inclusion of SEOA into WOA improved the global searching capability during the selection of CH and prevents worst fitness nodes from being selected as CH, since the spiral attacking behavior of SEOA is similar to the bubble-net characteristics of WOA. This CH selection integrates the spiral attacking principles of SEOA and contraction surrounding mechanism of WOA for improving computation accuracy to prevent frequent election process. It also included the strategy of levy flight strategy into SEOA for potentially avoiding premature convergence to attain better trade-off between the rate of exploration and exploitation in a more effective manner. The simulation results of the proposed HSWOADCP confirmed better network survivability rate, network residual energy and network overall throughput on par with the competitive CH selection schemes under different number of data transmission rounds.The statistical analysis of the proposed HSWOA-DCP scheme also confirmed its energy stability with respect to ANOVA test. 展开更多
关键词 clustering energy stability network lifetime seagull optimization algorithm(SEOA) whale optimization algorithm(WOA) wireless sensor networks(WSNs)
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部