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Human distribution and spatial-temporal clustering analysis of human brucellosis in China from 2012 to 2016 被引量:4
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作者 Pei-Feng Liang Yuan Zhao +2 位作者 Jian-Hua Zhao Dong-Feng Pan Zhong-Qin Guo 《Infectious Diseases of Poverty》 SCIE 2020年第5期124-124,共1页
Background:Brucellosis is a major public health issue in China,while its temporal and spatial distribution have not been studied in depth.This study aims to better understand the epidemiology of brucellosis in the mai... Background:Brucellosis is a major public health issue in China,while its temporal and spatial distribution have not been studied in depth.This study aims to better understand the epidemiology of brucellosis in the mainland of China,by investigating the human,temporal and spatial distribution and clustering characteristics of the disease.Methods:Human brucellosis data from the mainland of China between 2012 and 2016 were obtained from the China Information System for Disease Control and Prevention.The spatial autocorrelation analysis of ArcGIS10.6 and the spatial-temporal scanning analysis of SaTScan software were used to identify potential changes in the spatial and temporal distribution of human brucellosis in the mainland of China during the study period.Results:A total of 244348 human brucellosis cases were reported during the study period of 2012-2016.The average incidence of human brucellosis was higher in the 40-65 age group.The temporal clustering analysis showed that the high incidence of brucellosis occurred between March and July.The spatial clustering analysis showed that the location of brucellosis clustering in the mainland of China remained relatively fixed,mainly concentrated in most parts of northern China.The results of the spatial-temporal clustering analysis showed that Heilongjiang represents a primary clustering area,and the Tibet,Shanxi and Hubei provinces represent three secondary clustering areas.Conclusions:Human brucellosis remains a widespread challenge,particularly in northern China.The clustering analysis highlights potential high-risk human groups,time frames and areas,which may require special plans and resources to monitor and control the disease. 展开更多
关键词 Human brucellosis China clustering analysis Geographic information system SaTScan software
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New density clustering-based approach for failure mode and effect analysis considering opinion evolution and bounded confidence
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作者 WANG Jian ZHU Jingyi +1 位作者 SHI Hua LIU Huchen 《Journal of Systems Engineering and Electronics》 CSCD 2024年第6期1491-1506,共16页
Failure mode and effect analysis(FMEA)is a preven-tative risk evaluation method used to evaluate and eliminate fail-ure modes within a system.However,the traditional FMEA method exhibits many deficiencies that pose ch... Failure mode and effect analysis(FMEA)is a preven-tative risk evaluation method used to evaluate and eliminate fail-ure modes within a system.However,the traditional FMEA method exhibits many deficiencies that pose challenges in prac-tical applications.To improve the conventional FMEA,many modified FMEA models have been suggested.However,the majority of them inadequately address consensus issues and focus on achieving a complete ranking of failure modes.In this research,we propose a new FMEA approach that integrates a two-stage consensus reaching model and a density peak clus-tering algorithm for the assessment and clustering of failure modes.Firstly,we employ the interval 2-tuple linguistic vari-ables(I2TLVs)to express the uncertain risk evaluations provided by FMEA experts.Then,a two-stage consensus reaching model is adopted to enable FMEA experts to reach a consensus.Next,failure modes are categorized into several risk clusters using a density peak clustering algorithm.Finally,the proposed FMEA is illustrated by a case study of load-bearing guidance devices of subway systems.The results show that the proposed FMEA model can more easily to describe the uncertain risk information of failure modes by using the I2TLVs;the introduction of an endogenous feedback mechanism and an exogenous feedback mechanism can accelerate the process of consensus reaching;and the density peak clustering of failure modes successfully improves the practical applicability of FMEA. 展开更多
关键词 failure mode and effect analysis(FMEA) interval 2-tuple linguistic variable(I2TLV) consensus reaching density peak clustering algorithm
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Analysis of Patents Related to COVID-19-Based on Patent Clustering Model in Specific Fields
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作者 Fu Nan Li Qian Yuan Hongmei 《Asian Journal of Social Pharmacy》 2024年第4期371-382,共12页
Objective To improve the efficiency of patent clustering related to COVID-19 through the topic extraction algorithm and BERT model,and to help researchers understand the patent applications for novel corona virus.Meth... Objective To improve the efficiency of patent clustering related to COVID-19 through the topic extraction algorithm and BERT model,and to help researchers understand the patent applications for novel corona virus.Methods The weights of topic vector and BERT model vector were adjusted by cross-entropy loss algorithm to obtain joint vector.Then,k-means++algorithm was used for patent clustering after dimension reduction.Results and Conclusion The model was applied to patents for corona virus drugs,and five clustering topics were generated.Through comparison,it is proved that the clustering results of this model are more centralized and the differentiation between clusters is significant.The five clusters generated are visually analyzed to reveal the development status of patents for corona virus drugs. 展开更多
关键词 corona virus patent clustering patent analysis BERT model
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Genetic Diversity and Clustering Analysis of 48Cultivars of Olea euyopaea L. 被引量:1
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作者 宁德鲁 陈少瑜 +4 位作者 陈海云 李瑞 李勇杰 毛云玲 吴涛 《Agricultural Science & Technology》 CAS 2013年第9期1215-1219,共5页
Inter-simple sequence repeat(ISSR) molecular markers were applied to analyze the genetic diversity and clustering of 48 introduced and bred cultivars of Olea euyopaea L. Totally 106 DNA bands were amplified by 11 sc... Inter-simple sequence repeat(ISSR) molecular markers were applied to analyze the genetic diversity and clustering of 48 introduced and bred cultivars of Olea euyopaea L. Totally 106 DNA bands were amplified by 11 screened primers, including 99 polymorphic bands; the percentage of polymorphic loci was 93.40%, indicating a rich genetic diversity in Olea euyopaea L. germplasm resources. Based on Nei's genetic distances between various cultivars, a dendrogram of 48 cultivars of Olea euyopaea L. was constructed using unweighted pair-group(UPMGA)method,which showed that 48 cultivars were clustered into four main categories; 84.6% of native cultivars were clustered into two categories; most of introduced cultivars were clustered based on their sources and main usages but not on their geographic origins. This study will provide references for the utilization and further genetic improvement of Olea euyopaea L. germplasm resources. 展开更多
关键词 Olea euyopaea L. Genetic diversity clustering analysis
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Clustering analysis algorithm for security supervising data based on semantic description in coal mines 被引量:1
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作者 孟凡荣 周勇 夏士雄 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期354-357,共4页
In order to mine production and security information from security supervising data and to ensure security and safety involved in production and decision-making,a clustering analysis algorithm for security supervising... In order to mine production and security information from security supervising data and to ensure security and safety involved in production and decision-making,a clustering analysis algorithm for security supervising data based on a semantic description in coal mines is studied.First,the semantic and numerical-based hybrid description method of security supervising data in coal mines is described.Secondly,the similarity measurement method of semantic and numerical data are separately given and a weight-based hybrid similarity measurement method for the security supervising data based on a semantic description in coal mines is presented.Thirdly,taking the hybrid similarity measurement method as the distance criteria and using a grid methodology for reference,an improved CURE clustering algorithm based on the grid is presented.Finally,the simulation results of a security supervising data set in coal mines validate the efficiency of the algorithm. 展开更多
关键词 semantic description clustering analysis algorithm similarity measurement
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Clustering Analysis on Large Grained Brassica napus Materials Based on the Optimized ACGM Markers
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作者 俎峰 李静 +6 位作者 罗延青 赵凯琴 马芳 陈苇 王敬乔 李劲峰 董云松 《Agricultural Science & Technology》 CAS 2012年第11期2265-2268,共4页
[Objective] This study aimed to develop ACGM markers for the clustering analysis of large grained Brassica napus materials. [Method] A total of 44 pairs of ACGM primers were designed according to 18 genes related to A... [Objective] This study aimed to develop ACGM markers for the clustering analysis of large grained Brassica napus materials. [Method] A total of 44 pairs of ACGM primers were designed according to 18 genes related to Arabidopsis grain development and their homologous rape EST sequences. After electrophoresis, 18 pairs of ACGM primers were selected for the clustering analysis of 16 larger grained samples and four fine grained samples of rapeseed. [Result] PCR result showed that 2-6 specific bands were respectively amplified by each pair of primes, and all the bands were polymorphic and repeatable, suggesting that the optimized ACGM markers were useful for clustering analysis of B. napus species. Clustering analysis revealed that the 20 rapeseed samples were divided into three clusters A, B, and C at similarity coefficient 0.6. Then, the clusters A and B were further divided into five sub clusters A1, A2, A3, B1 and B2 at similarity coefficient 0.67. [Conclusion] This study will provide theoretical and practical values for rape breeding. 展开更多
关键词 Brassica napus Large grain clustering analysis ACGM marker
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Study on Trace Elements in Rehmannia glutinosa Libosch. by Principal Component Analysis and Clustering Analysis
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作者 申明金 陈丽 曹洪斌 《Agricultural Science & Technology》 CAS 2013年第12期1764-1768,共5页
[Objective] This study aimed to investigate the trace elements in Rehman- nia glutinosa Libosch. by using principal component analysis and clustering analysis. [Method] Principal component analysis and clustering anal... [Objective] This study aimed to investigate the trace elements in Rehman- nia glutinosa Libosch. by using principal component analysis and clustering analysis. [Method] Principal component analysis and clustering analysis of R. glutinosa medicinal materials from different sources were conducted with contents of six trace elements as indices. [Result] The principal component analysis could comprehen- sively evaluate the quality of R. glutinosa samples with objective results which was consistent with the results of clustering analysis. [Conclusion] Principal component analysis and clustering analysis methods can be used for the quality evaluation of Chinese medicinal materials with multiple indices. 展开更多
关键词 Rehmannia glutinosa Libosch. (Radix Rehmanniae) Trace elements Principal component analysis clustering analysis
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Characterization and genomic analysis of Pseudoalteromonas phage v B_Pal P_Y7,representing a novel viral genus,Miuvirus
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作者 Miaolan WU Hongmin WANG +11 位作者 Ye MI Yantao LIANG Kaiyang ZHENG Yundan LIU Yue DONG Linyi REN Yue SU Hongbing SHAO Yeong Yik SUNG Wen Jye MOK Li Lian WONG Min WANG 《Journal of Oceanology and Limnology》 2025年第1期299-312,共14页
Pseudoalteromonas is a group of marine bacteria widespread in diverse marine sediments,producing a wide range of bioactive compounds.However,only a limited number of Pseudoalteromonas phages have been isolated and stu... Pseudoalteromonas is a group of marine bacteria widespread in diverse marine sediments,producing a wide range of bioactive compounds.However,only a limited number of Pseudoalteromonas phages have been isolated and studied.In this study,a novel lytic Pseudoalteromonas phage,denoted as vB_PalP_Y7,was isolated from sewage samples collected at the Seafood Market in Qingdao,China.vB_PalP_Y7 remained stable across a wide range of temperatures(-20–50℃)and a wide pH range(3–12).The vB_PalP_Y7 phage harbors a linear double-stranded DNA molecule of 57699 base pairs(bp)with a G+C content of 45.90%.Furthermore,it is predicted to contain 58 open reading frames(ORFs).Phylogenetic analysis and protein network relationship analysis revealed low similarity between vB_PalP_Y7 and viruses in the ICTV and IMG/VR4 database,suggesting that vB_PalP_Y7 may be a potential new genus,Miuvirus.This study contributed valuable insights to comprehend the relationship between Pseudoalteromonas phages and their host organisms. 展开更多
关键词 Pseudoalteromonas phage genomic analysis phylogenetic analysis viral cluster
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Integrating petrophysical data into efficient iterative cluster analysis for electrofacies identification in clastic reservoirs
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作者 Mohammed A.Abbas Watheq J.Al-Mudhafar +1 位作者 Aqsa Anees David A.Wood 《Energy Geoscience》 EI 2024年第4期291-305,共15页
Efficient iterative unsupervised machine learning involving probabilistic clustering analysis with the expectation-maximization(EM)clustering algorithm is applied to categorize reservoir facies by exploiting latent an... Efficient iterative unsupervised machine learning involving probabilistic clustering analysis with the expectation-maximization(EM)clustering algorithm is applied to categorize reservoir facies by exploiting latent and observable well-log variables from a clastic reservoir in the Majnoon oilfield,southern Iraq.The observable well-log variables consist of conventional open-hole,well-log data and the computer-processed interpretation of gamma rays,bulk density,neutron porosity,compressional sonic,deep resistivity,shale volume,total porosity,and water saturation,from three wells located in the Nahr Umr reservoir.The latent variables include shale volume and water saturation.The EM algorithm efficiently characterizes electrofacies through iterative machine learning to identify the local maximum likelihood estimates(MLE)of the observable and latent variables in the studied dataset.The optimized EM model developed successfully predicts the core-derived facies classification in two of the studied wells.The EM model clusters the data into three distinctive reservoir electrofacies(F1,F2,and F3).F1 represents a gas-bearing electrofacies with low shale volume(Vsh)and water saturation(Sw)and high porosity and permeability values identifying it as an attractive reservoir target.The results of the EM model are validated using nuclear magnetic resonance(NMR)data from the third studied well for which no cores were recovered.The NMR results confirm the effectiveness and accuracy of the EM model in predicting electrofacies.The utilization of the EM algorithm for electrofacies classification/cluster analysis is innovative.Specifically,the clusters it establishes are less rigidly constrained than those derived from the more commonly used K-means clustering method.The EM methodology developed generates dependable electrofacies estimates in the studied reservoir intervals where core samples are not available.Therefore,once calibrated with core data in some wells,the model is suitable for application to other wells that lack core data. 展开更多
关键词 cluster analysis Electrofacies classification Expectation-maximization(EM)algorithm Clastic reservoir Maximum likelihood estimate(MLE)
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ARHCS (Automatic Rainfall Half-Life Cluster System): A Landslides Early Warning System (LEWS) Using Cluster Analysis and Automatic Threshold Definition
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作者 Cassiano Antonio Bortolozo Luana Albertani Pampuch +8 位作者 Marcio Roberto Magalhães De Andrade Daniel Metodiev Adenilson Roberto Carvalho Tatiana Sussel Gonçalves Mendes Tristan Pryer Harideva Marturano Egas Rodolfo Moreda Mendes Isadora Araújo Sousa Jenny Power 《International Journal of Geosciences》 CAS 2024年第1期54-69,共16页
A significant portion of Landslide Early Warning Systems (LEWS) relies on the definition of operational thresholds and the monitoring of cumulative rainfall for alert issuance. These thresholds can be obtained in vari... A significant portion of Landslide Early Warning Systems (LEWS) relies on the definition of operational thresholds and the monitoring of cumulative rainfall for alert issuance. These thresholds can be obtained in various ways, but most often they are based on previous landslide data. This approach introduces several limitations. For instance, there is a requirement for the location to have been previously monitored in some way to have this type of information recorded. Another significant limitation is the need for information regarding the location and timing of incidents. Despite the current ease of obtaining location information (GPS, drone images, etc.), the timing of the event remains challenging to ascertain for a considerable portion of landslide data. Concerning rainfall monitoring, there are multiple ways to consider it, for instance, examining accumulations over various intervals (1 h, 6 h, 24 h, 72 h), as well as in the calculation of effective rainfall, which represents the precipitation that actually infiltrates the soil. However, in the vast majority of cases, both the thresholds and the rain monitoring approach are defined manually and subjectively, relying on the operators’ experience. This makes the process labor-intensive and time-consuming, hindering the establishment of a truly standardized and rapidly scalable methodology on a large scale. In this work, we propose a Landslides Early Warning System (LEWS) based on the concept of rainfall half-life and the determination of thresholds using Cluster Analysis and data inversion. The system is designed to be applied in extensive monitoring networks, such as the one utilized by Cemaden, Brazil’s National Center for Monitoring and Early Warning of Natural Disasters. 展开更多
关键词 Landslides Early Warning System (LEWS) cluster analysis LANDSLIDES Brazil
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Comparative Analysis of Differences among Northern,Jiangnan,and Lingnan Classical Private Gardens Using Principal Component Cluster Method
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作者 Lijuan Sun Hui Wang 《Journal of Architectural Research and Development》 2024年第5期20-29,共10页
This paper investigates the design essence of Chinese classical private gardens,integrating their design elements and fundamental principles.It systematically analyzes the unique characteristics and differences among ... This paper investigates the design essence of Chinese classical private gardens,integrating their design elements and fundamental principles.It systematically analyzes the unique characteristics and differences among classical private gardens in the Northern,Jiangnan,and Lingnan regions.The study examines nine classical private gardens from Northern China,Jiangnan,and Lingnan by utilizing the advanced tool of principal component cluster analysis.Based on literature analysis and field research,273 variables were selected for principal component analysis,from which four components with higher contribution rates were chosen for further study.Subsequently,we employed clustering analysis techniques to compare the differences among the three types of gardens.The results reveal that the first principal component effectively highlights the differences between Jiangnan and Lingnan private gardens.The second principal component serves as the key to defining the types of Northern private gardens and distinguishing them from the other two types,and the third principal component indicates that Lingnan private gardens can be categorized into two distinct types as well. 展开更多
关键词 Classical gardens Private gardens DIFFERENCES Principal component analysis cluster analysis
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Clustering Structure Analysis in Time-Series Data With Density-Based Clusterability Measure 被引量:6
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作者 Juho Jokinen Tomi Raty Timo Lintonen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第6期1332-1343,共12页
Clustering is used to gain an intuition of the struc tures in the data.Most of the current clustering algorithms pro duce a clustering structure even on data that do not possess such structure.In these cases,the algor... Clustering is used to gain an intuition of the struc tures in the data.Most of the current clustering algorithms pro duce a clustering structure even on data that do not possess such structure.In these cases,the algorithms force a structure in the data instead of discovering one.To avoid false structures in the relations of data,a novel clusterability assessment method called density-based clusterability measure is proposed in this paper.I measures the prominence of clustering structure in the data to evaluate whether a cluster analysis could produce a meaningfu insight to the relationships in the data.This is especially useful in time-series data since visualizing the structure in time-series data is hard.The performance of the clusterability measure is evalu ated against several synthetic data sets and time-series data sets which illustrate that the density-based clusterability measure can successfully indicate clustering structure of time-series data. 展开更多
关键词 clustering EXPLORATORY data analysis time-series UNSUPERVISED LEARNING
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Identifying a competency improvement strategy for infection prevention and control professionals:A rapid systematic review and cluster analysis
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作者 Nuo Chen Shunning Li +3 位作者 Zhengling Kuang Ting Gong Weilong Zhou Ying Wang 《Health Care Science》 2024年第1期53-66,共14页
Remarkable progress has been made in infection prevention and control(IPC)in many countries,but some gaps emerged in the context of the coronavirus disease 2019(COVID-19)pandemic.Core capabilities such as standard cli... Remarkable progress has been made in infection prevention and control(IPC)in many countries,but some gaps emerged in the context of the coronavirus disease 2019(COVID-19)pandemic.Core capabilities such as standard clinical precautions and tracing the source of infection were the focus of IPC in medical institutions during the pandemic.Therefore,the core competences of IPC professionals during the pandemic,and how these contributed to successful prevention and control of the epidemic,should be studied.To investigate,using a systematic review and cluster analysis,fundamental improvements in the competences of infection control and prevention professionals that may be emphasized in light of the COVID-19 pandemic.We searched the PubMed,Embase,Cochrane Library,Web of Science,CNKI,WanFang Data,and CBM databases for original articles exploring core competencies of IPC professionals during the COVID-19 pandemic(from January 1,2020 to February 7,2023).Weiciyun software was used for data extraction and the Donohue formula was followed to distinguish high-frequency technical terms.Cluster analysis was performed using the within-group linkage method and squared Euclidean distance as the metric to determine the priority competencies for development.We identified 46 studies with 29 high-frequency technical terms.The most common term was“infection prevention and control training”(184 times,17.3%),followed by“hand hygiene”(172 times,16.2%).“Infection prevention and control in clinical practice”was the most-reported core competency(367 times,34.5%),followed by“microbiology and surveillance”(292 times,27.5%).Cluster analysis showed two key areas of competence:Category 1(program management and leadership,patient safety and occupational health,education and microbiology and surveillance)and Category 2(IPC in clinical practice).During the COVID-19 pandemic,IPC program management and leadership,microbiology and surveillance,education,patient safety,and occupational health were the most important focus of development and should be given due consideration by IPC professionals. 展开更多
关键词 infection prevention and control professionals competency improvement cluster analysis COVID-19 REVIEW
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Optimization of constitutive parameters of foundation soils k-means clustering analysis 被引量:7
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作者 Muge Elif Orakoglu Cevdet Emin Ekinci 《Research in Cold and Arid Regions》 CSCD 2013年第5期626-636,共11页
The goal of this study was to optimize the constitutive parameters of foundation soils using a k-means algorithm with clustering analysis. A database was collected from unconfined compression tests, Proctor tests and ... The goal of this study was to optimize the constitutive parameters of foundation soils using a k-means algorithm with clustering analysis. A database was collected from unconfined compression tests, Proctor tests and grain distribution tests of soils taken from three different types of foundation pits: raft foundations, partial raft foundations and strip foundations. k-means algorithm with clustering analysis was applied to determine the most appropriate foundation type given the un- confined compression strengths and other parameters of the different soils. 展开更多
关键词 foundation soil regression model k-means clustering analysis
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Unsupervised seismic facies analysis using sparse representation spectral clustering 被引量:5
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作者 Wang Yao-Jun Wang Liang-Ji +3 位作者 Li Kun-Hong Liu Yu Luo Xian-Zhe Xing Kai 《Applied Geophysics》 SCIE CSCD 2020年第4期533-543,共11页
Traditional unsupervised seismic facies analysis techniques need to assume that seismic data obey mixed Gaussian distribution.However,fi eld seismic data may not meet this condition,thereby leading to wrong classifi c... Traditional unsupervised seismic facies analysis techniques need to assume that seismic data obey mixed Gaussian distribution.However,fi eld seismic data may not meet this condition,thereby leading to wrong classifi cation in the application of this technology.This paper introduces a spectral clustering technique for unsupervised seismic facies analysis.This algorithm is based on on the idea of a graph to cluster the data.Its kem is that seismic data are regarded as points in space,points can be connected with the edge and construct to graphs.When the graphs are divided,the weights of the edges between the different subgraphs are as low as possible,whereas the weights of the inner edges of the subgraph should be as high as possible.That has high computational complexity and entails large memory consumption for spectral clustering algorithm.To solve the problem this paper introduces the idea of sparse representation into spectral clustering.Through the selection of a small number of local sparse representation points,the spectral clustering matrix of all sample points is approximately represented to reduce the cost of spectral clustering operation.Verifi cation of physical model and fi eld data shows that the proposed approach can obtain more accurate seismic facies classification results without considering the data meet any hypothesis.The computing efficiency of this new method is better than that of the conventional spectral clustering method,thereby meeting the application needs of fi eld seismic data. 展开更多
关键词 seismic facies analysis spectral clustering sparse representation and unsupervised clustering
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Spatial-temporal difference between nitrate in groundwater and nitrogen in soil based on geostatistical analysis 被引量:2
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作者 Xiu-bo Sun Chang-lai Guo +3 位作者 Jing Zhang Jia-quan Sun Jian Cui Mao-hua Liu 《Journal of Groundwater Science and Engineering》 2023年第1期37-46,共10页
The study of temporal and spatial variations of nitrate in groundwater under different soil nitrogen environments is helpful to the security of groundwater resources in agricultural areas.In this paper,based on 320 gr... The study of temporal and spatial variations of nitrate in groundwater under different soil nitrogen environments is helpful to the security of groundwater resources in agricultural areas.In this paper,based on 320 groups of soil and groundwater samples collected at the same time,geostatistical analysis and multiple regression analysis were comprehensively used to conduct the evaluation of nitrogen contents in both groundwater and soil.From May to August,as the nitrification of groundwater is dominant,the average concentration of nitrate nitrogen is 34.80 mg/L;The variation of soil ammonia nitrogen and nitrate nitrogen is moderate from May to July,and the variation coefficient decreased sharply and then increased in August.There is a high correlation between the nitrate nitrogen in groundwater and soil in July,and there is a high correlation between the nitrate nitrogen in groundwater and ammonium nitrogen in soil in August and nitrate nitrogen in soil in July.From May to August,the area of low groundwater nitrate nitrogen in 0-5 mg/L and 5-10 mg/L decreased from 10.97%to 0,and the proportion of high-value area(greater than 70 mg/L)increased from 21.19%to 27.29%.Nitrate nitrogen is the main factor affecting the quality of groundwater.The correlation analysis of nitrate nitrogen in groundwater,nitrate nitrogen in soil and ammonium nitrogen shows that they have a certain period of delay.The areas with high concentration of nitrate in groundwater are mainly concentrated in the western part of the study area,which has a high consistency with the high value areas of soil nitrate distribution from July to August,and a high difference with the spatial position of soil ammonia nitrogen distribution in August. 展开更多
关键词 GROUNDWATER NITRATE SOIL spatial-temporal variation Geostatistical analysis
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Evaluation and classification of residential greenbelt quality based on factor analysis & clustering analysis:An example of Xinxiang City,China 被引量:1
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作者 乔丽芳 张毅川 齐安国 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第4期311-314,共4页
Five factors expressing greenbelt quality and one factor expressing quantity were adopted for evaluation of the residential greenbelt, and the AHP (Analytical Hierarchy Process) method was used to determine the valu... Five factors expressing greenbelt quality and one factor expressing quantity were adopted for evaluation of the residential greenbelt, and the AHP (Analytical Hierarchy Process) method was used to determine the value of factors. Thirty residential areas were selected as the samples. Two principal components were extracted and their expression was constructed by method of factor anlysis, therefore, quality evaluation of residential greenbelt was obtained. The accuracy of the function and implement quality classification toward the residential greenbelts in Xinxiang City were validated by clustering analysis method. The results showed that the greenbelt quality of fourteen residential areas was higher than the average level, of which eleven were newly-built residential areas. The 30 residential areas were classified into three types according to their greenbelt features and their formation by clustering analysis method. Finally rational proposal basing on aforesaid evaluating results was proposed for construction and renewal of residential greenbelt, upon which directive basis was provided for construction and renewal of residential greenbelt. 展开更多
关键词 residential area greenbelt quality EVALUATION factor analysis clustering analysis
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Massive Power Device Condition Monitoring Data Feature Extraction and Clustering Analysis using MapReduce and Graph Model 被引量:4
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作者 Hongtao Shen Peng Tao +1 位作者 Pei Zhao Hao Ma 《CES Transactions on Electrical Machines and Systems》 CSCD 2019年第2期221-230,共10页
Effective storage,processing and analyzing of power device condition monitoring data faces enormous challenges.A framework is proposed that can support both MapReduce and Graph for massive monitoring data analysis at ... Effective storage,processing and analyzing of power device condition monitoring data faces enormous challenges.A framework is proposed that can support both MapReduce and Graph for massive monitoring data analysis at the same time based on Aliyun DTplus platform.First,power device condition monitoring data storage based on MaxCompute table and parallel permutation entropy feature extraction based on MaxCompute MapReduce are designed and implemented on DTplus platform.Then,Graph based k-means algorithm is implemented and used for massive condition monitoring data clustering analysis.Finally,performance tests are performed to compare the execution time between serial program and parallel program.Performance is analyzed from CPU cores consumption,memory utilization and parallel granularity.Experimental results show that the designed framework and parallel algorithms can efficiently process massive power device condition monitoring data. 展开更多
关键词 clustering analysis GRAPH feature extraction MAPREDUCE maxcompute power device condition monitoring.
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AN ANALYSIS OF THE APPLICABILITY OF FUZZY CLUSTERING IN ESTABLISHING AN INDEX FOR THE EVALUATION OF METEOROLOGICAL SERVICE SATISFACTION 被引量:1
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作者 YAN Min-hui YAO Xiu-ping +2 位作者 WANG Lei JIANG Li-xia ZHANG Jin-feng 《Journal of Tropical Meteorology》 SCIE 2020年第1期103-110,共8页
An evaluation index is a prerequisite for the scientific evaluation of a public meteorological service.This paper aims to explore a technical method for determining and screening evaluation indicators.Based on public ... An evaluation index is a prerequisite for the scientific evaluation of a public meteorological service.This paper aims to explore a technical method for determining and screening evaluation indicators.Based on public satisfaction survey data obtained in Wafangdian,China in 2010,this study investigates the suitability of fuzzy clustering analysis method in establishing an evaluation index.Through quantitative analysis of multilayer fuzzy clustering of various evaluation indicators,correlation analysis indicates that if the results of clustering were identical for two evaluation indicators in the same sub-evaluation layer,then one indicator could be removed,or the two indicators merged.For evaluation indicators in different sub-evaluation layers,although clustering reveals attribute correlations,these indicators may not be substituted for one another.Analysis of the applicability of the fuzzy clustering method shows that it plays a certain role in the establishment and correction of an evaluation index. 展开更多
关键词 evaluation index multilayer fuzzy clustering analysis range transformation transitional closure method
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The Bio-Geographical Regions Division of Global Terrestrial Animal by Multivariate Similarity Clustering Analysis Method 被引量:3
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作者 Qi Shen Jiqi Lu +3 位作者 Shujie Zhang Zhixing You Yingdang Ren Xiaocheng Shen 《Open Journal of Ecology》 2022年第3期236-255,共20页
A novel multivariate similarity clustering analysis (MSCA) approach was used to estimate a biogeographical division scheme for the global terrestrial fauna and was compared against other widely used clustering algorit... A novel multivariate similarity clustering analysis (MSCA) approach was used to estimate a biogeographical division scheme for the global terrestrial fauna and was compared against other widely used clustering algorithms. The faunal dataset included almost all terrestrial and freshwater fauna, a total of 4631 families, 141,814 genera, and 1,334,834 species. Our findings demonstrated that suitable results were only obtained with the MSCA method, which was associated with distinct hierarchies, reasonable structuring, and furthermore, conformed to biogeographical criteria. A total of seven kingdoms and 20 sub-kingdoms were identified. We discovered that the clustering results for the higher and lower animals did not differ significantly, leading us to consider that the analysis result is convincing as the first zoogeographical division scheme for global all terrestrial animals. 展开更多
关键词 Global Animal Multivariate Similarity clustering analysis BIOGEOGRAPHY REGIONALIZATION
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