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Composition Analysis and Identification of Ancient Glass Products Based on L1 Regularization Logistic Regression
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作者 Yuqiao Zhou Xinyang Xu Wenjing Ma 《Applied Mathematics》 2024年第1期51-64,共14页
In view of the composition analysis and identification of ancient glass products, L1 regularization, K-Means cluster analysis, elbow rule and other methods were comprehensively used to build logical regression, cluste... In view of the composition analysis and identification of ancient glass products, L1 regularization, K-Means cluster analysis, elbow rule and other methods were comprehensively used to build logical regression, cluster analysis, hyper-parameter test and other models, and SPSS, Python and other tools were used to obtain the classification rules of glass products under different fluxes, sub classification under different chemical compositions, hyper-parameter K value test and rationality analysis. Research can provide theoretical support for the protection and restoration of ancient glass relics. 展开更多
关键词 Glass Composition L1 Regularization Logistic Regression Model K-Means clustering analysis Elbow Rule Parameter Verification
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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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Integrated classification method of tight sandstone reservoir based on principal component analysise simulated annealing genetic algorithmefuzzy cluster means
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作者 Bo-Han Wu Ran-Hong Xie +3 位作者 Li-Zhi Xiao Jiang-Feng Guo Guo-Wen Jin Jian-Wei Fu 《Petroleum Science》 SCIE EI CSCD 2023年第5期2747-2758,共12页
In this research,an integrated classification method based on principal component analysis-simulated annealing genetic algorithm-fuzzy cluster means(PCA-SAGA-FCM)was proposed for the unsupervised classification of tig... In this research,an integrated classification method based on principal component analysis-simulated annealing genetic algorithm-fuzzy cluster means(PCA-SAGA-FCM)was proposed for the unsupervised classification of tight sandstone reservoirs which lack the prior information and core experiments.A variety of evaluation parameters were selected,including lithology characteristic parameters,poro-permeability quality characteristic parameters,engineering quality characteristic parameters,and pore structure characteristic parameters.The PCA was used to reduce the dimension of the evaluation pa-rameters,and the low-dimensional data was used as input.The unsupervised reservoir classification of tight sandstone reservoir was carried out by the SAGA-FCM,the characteristics of reservoir at different categories were analyzed and compared with the lithological profiles.The analysis results of numerical simulation and actual logging data show that:1)compared with FCM algorithm,SAGA-FCM has stronger stability and higher accuracy;2)the proposed method can cluster the reservoir flexibly and effectively according to the degree of membership;3)the results of reservoir integrated classification match well with the lithologic profle,which demonstrates the reliability of the classification method. 展开更多
关键词 Tight sandstone Integrated reservoir classification Principal component analysis Simulated annealing genetic algorithm Fuzzy cluster means
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Analysis of the Employment Situation of Non Private Enterprises in Various Regions of China
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作者 Junyi Wang 《Open Journal of Applied Sciences》 2024年第1期131-144,共14页
In the past 30 years, Chinese enterprises have been a hot topic of discussion and concern among the general public in terms of economic and social status, ownership structure, business mechanism, and management level.... In the past 30 years, Chinese enterprises have been a hot topic of discussion and concern among the general public in terms of economic and social status, ownership structure, business mechanism, and management level. Solving the problem of employment for the people is an important prerequisite for their peaceful living and work, as well as a prerequisite and foundation for building a harmonious society. The employment situation of private enterprises has always been of great concern to the outside world, and these two major jobs have always occupied an important position in the employment field of China that cannot be ignored. With the establishment of the market economy system, individual and private enterprises have become important components of the socialist economy, making significant contributions to economic development and social progress. The rapid development of China’s economy, on the one hand, is the embodiment of the superiority of China’s socialist market economic system, and on the other hand, it is the role of the tertiary industry and private enterprises in promoting the national economy. Since the 1990s, China’s private enterprises have become a new economic growth point for local and even national countries, and are one of the important ways to arrange employment and achieve social stability. This paper studies the employment of private enterprises and individuals from the perspective of statistics, extracts relevant data from China statistical Yearbook, uses the relevant knowledge of statistics to process the data, obtains the conclusion and puts forward relevant constructive suggestions. 展开更多
关键词 Correlation analysis of Employment Numbers Factor analysis Principal Component analysis cluster analysis
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Slope deformation partitioning and monitoring points optimization based on cluster analysis
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作者 LI Yuan-zheng SHEN Jun-hui +3 位作者 ZHANG Wei-xin ZHANG Kai-qiang PENG Zhang-hai HUANG Meng 《Journal of Mountain Science》 SCIE CSCD 2023年第8期2405-2421,共17页
The scientific and fair positioning of monitoring locations for surface displacement on slopes is a prerequisite for early warning and forecasting.However,there is no specific provision on how to effectively determine... The scientific and fair positioning of monitoring locations for surface displacement on slopes is a prerequisite for early warning and forecasting.However,there is no specific provision on how to effectively determine the number and location of monitoring points according to the actual deformation characteristics of the slope.There are still some defects in the layout of monitoring points.To this end,based on displacement data series and spatial location information of surface displacement monitoring points,by combining displacement series correlation and spatial distance influence factors,a spatial deformation correlation calculation model of slope based on clustering analysis was proposed to calculate the correlation between different monitoring points,based on which the deformation area of the slope was divided.The redundant monitoring points in each partition were eliminated based on the partition's outcome,and the overall optimal arrangement of slope monitoring points was then achieved.This method scientifically addresses the issues of slope deformation zoning and data gathering overlap.It not only eliminates human subjectivity from slope deformation zoning but also increases the efficiency and accuracy of slope monitoring.In order to verify the effectiveness of the method,a sand-mudstone interbedded CounterTilt excavation slope in the Chongqing city of China was used as the research object.Twenty-four monitoring points deployed on this slope were monitored for surface displacement for 13 months.The spatial location of the monitoring points was discussed.The results show that the proposed method of slope deformation zoning and the optimized placement of monitoring points are feasible. 展开更多
关键词 Excavation slope Surface displacement monitoring Spatial deformation analysis clustering analysis Slope deformation partitioning Monitoring point optimization
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Fuzzy cluster analysis of water mass in the western Taiwan Strait in spring 2019
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作者 Zhiyuan Hu Jia Zhu +4 位作者 Longqi Yang Zhenyu Sun Xin Guo Zhaozhang Chen Linfeng Huang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第12期1-8,共8页
The classification of the springtime water mass has an important influence on the hydrography,regional climate change and fishery in the Taiwan Strait.Based on 58 stations of CTD profiling data collected in the wester... The classification of the springtime water mass has an important influence on the hydrography,regional climate change and fishery in the Taiwan Strait.Based on 58 stations of CTD profiling data collected in the western and southwestern Taiwan Strait during the spring cruise of 2019,we analyze the spatial distributions of temperature(T)and salinity(S)in the investigation area.Then by using the fuzzy cluster method combined with the T-S similarity number,we classify the investigation area into 5 water masses:the Minzhe Coastal Water(MZCW),the Taiwan Strait Mixed Water(TSMW),the South China Sea Surface Water(SCSSW),the South China Sea Subsurface Water(SCSUW)and the Kuroshio Branch Water(KBW).The MZCW appears in the near surface layer along the western coast of Taiwan Strait,showing low-salinity(<32.0)tongues near the Minjiang River Estuary and the Xiamen Bay mouth.The TSMW covers most upper layer of the investigation area.The SCSSW is mainly distributed in the upper layer of the southwestern Taiwan Strait,beneath which is the SCSUW.The KBW is a high temperature(core value of 26.36℃)and high salinity(core value of 34.62)water mass located southeast of the Taiwan Bank and partially in the central Taiwan Strait. 展开更多
关键词 water mass classification western Taiwan Strait fuzzy cluster analysis T-S similarity number
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The Establishment of Mathematical Models for the Composition Analysis and Identification of Ancient Glass Products
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作者 Jenny Zhang Ding Li +1 位作者 Yu Xie Junfeng Xiang 《Open Journal of Applied Sciences》 2023年第11期2149-2171,共23页
Glass is the precious material evidence of the trade of the early Silk Road. The ancient glass was easily affected by the environmental impact and weathering, and the change of composition ratios affected the correct ... Glass is the precious material evidence of the trade of the early Silk Road. The ancient glass was easily affected by the environmental impact and weathering, and the change of composition ratios affected the correct judgment of its category. In this paper, mathematical models and methods such as Chi-square test, weighted average method, principal component analysis, cluster analysis, binary classification model and grey correlation analysis were used comprehensively to analyze the data of sample glass products combined with their categories. The results showed that the weathered high-potassium glass could be divided into 12, 9, 10 and 27, 7, 22 and so on. 展开更多
关键词 Principal Component analysis System clustering Sensitivity analysis Binary Classification Model Logistic Regression analysis Grey Correlation analysis
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CPSO: Chaotic Particle Swarm Optimization for Cluster Analysis
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作者 Jiaji Wang 《Journal of Artificial Intelligence and Technology》 2023年第2期46-52,共7页
Background:To solve the cluster analysis better,we propose a new method based on the chaotic particle swarm optimization(CPSO)algorithm.Methods:In order to enhance the performance in clustering,we propose a novel meth... Background:To solve the cluster analysis better,we propose a new method based on the chaotic particle swarm optimization(CPSO)algorithm.Methods:In order to enhance the performance in clustering,we propose a novel method based on CPSO.We first evaluate the clustering performance of this model using the variance ratio criterion(VRC)as the evaluation metric.The effectiveness of the CPSO algorithm is compared with that of the traditional particle swarm optimization(PSO)algorithm.The CPSO aims to improve the VRC value while avoiding local optimal solutions.The simulated dataset is set at three levels of overlapping:non-overlapping,partial overlapping,and severe overlapping.Finally,we compare CPSO with two other methods.Results:By observing the comparative results,our proposed CPSO method performs outstandingly.In the conditions of non-overlapping,partial overlapping,and severe overlapping,our method has the best VRC values of 1683.2,620.5,and 275.6,respectively.The mean VRC values in these three cases are 1683.2,617.8,and 222.6.Conclusion:The CPSO performed better than other methods for cluster analysis problems.CPSO is effective for cluster analysis. 展开更多
关键词 cluster analysis chaotic particle swarm optimization variance ratio criterion
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Establishment of HPLC Fingerprint, Cluster Analysis and Principle Component Analysis of Citri Reticulatae Pericarpium Viride 被引量:4
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作者 Beibei JIN Xiangping PEI Huizhen LIANG 《Medicinal Plant》 CAS 2019年第1期69-73,共5页
[Objectives] This study aimed to establish HPLC fingerprint and conduct cluster analysis and principle component analysis for Citri Reticulatae Pericarpium Viride. [Methods] Using the HPLC method, the determination wa... [Objectives] This study aimed to establish HPLC fingerprint and conduct cluster analysis and principle component analysis for Citri Reticulatae Pericarpium Viride. [Methods] Using the HPLC method, the determination was performed on XSelect~&#x00AE; HSS T3-C_(18) column with mobile phase of acetonitrile-0.5% acetic acid solution(gradient elution) at the flow rate of 1.0 mL/min. The detection wavelength was 360 nm. The column temperature was 25℃. The sample size was 10 μL. With peak of hesperidin as the reference, HPLC fingerprints of 10 batches of Citri Reticulatae Pericarpium Viride were determined. The similarity of the 10 batches of samples was evaluated by Similarity Evaluation System for Chromatographic Fingerprint of TCM(2012 edition) to determine the common peaks. Cluster analysis and principal component analysis were performed by using SPSS 17.0 statistical software. [Results] The HPLC fingerprints of the 10 batches of medicinal materials had total 11 common peaks, and the similarity was 0.919-1.000, indicating that the chemical composition of the 10 batches of medicinal materials was consistent. There were 11 common components in the 10 batches of medicinal materials, but their contents were different. When the Euclidean distance was 20, the 10 batches of samples were divided into two categories, S4 in the first category, and the others in the second one. When the Euclidean distance was 5, the second category could be further divided into two sub-categories, S1 and S10 in one sub-category, and S2, S3, S5, S6, S7, S8 and S9 in the other one. The principle component analysis showed that cumulative contribution rate of the two main component factors was 92.797%, and the comprehensive score of S7 was the highest with the best quality. [Conclusions] The results of HPLC fingerprinting, cluster analysis and principle component analysis can provide reference for the quality control of Citri Reticulatae Pericarpium Viride. 展开更多
关键词 Citri Reticulatae Pericarpium Viride HPLC FINGERPRINT cluster analysis PRINCIPLE COMPONENT analysis
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Vertical Migrating and Cluster Analysis of Soil Mesofauna at Dongying Halophytes Garden in Yellow River Delta 被引量:3
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作者 He Fu-xia Xie Tong-yin +1 位作者 Xie Gui-lin Fu Rong-shu 《Journal of Northeast Agricultural University(English Edition)》 CAS 2014年第1期25-30,共6页
For the first time,we used Tullgren method made a study on vertical migrating and cluster analysis of the soil mesofauna in Dongying Halophytes Garden in the Yellow River Delta(YRD),Shandong Province.The results showe... For the first time,we used Tullgren method made a study on vertical migrating and cluster analysis of the soil mesofauna in Dongying Halophytes Garden in the Yellow River Delta(YRD),Shandong Province.The results showed that the soil mesofauna tended to gather on soil surface in most samples at most times,but the vertical migrating greatly varied in different seasons or environment conditions.Acari was the dominant group.The index of diversity of the soil fauna was correlated with the index of evenness.The Acari's number of individuals infected other species and numbers.Dominant group-Acari made greater contribution to the result of cluster analysis,and there were significant differences between communities in different habitats by cluster analysis with both Bray-Curtis and Jaccard similarity coefficient. 展开更多
关键词 HALOPHYTES SOIL MESOFAUNA VERTIcaL migrating cluster analysis
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The cluster analysis of the water masses in western Taiwan Strait from hydrologic And chemical factors 被引量:2
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作者 Huang Ziqiang and Ji Weidong (Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1994年第4期501-518,共18页
TheclusteranalysisofthewatermassesinwesternTaiwanStraitfromhydrologicandchemicalfactors¥HuangZiqiangandJiWei... TheclusteranalysisofthewatermassesinwesternTaiwanStraitfromhydrologicandchemicalfactors¥HuangZiqiangandJiWeidong(ReceivedAugu... 展开更多
关键词 The WESTERN TAIWAN STRAIT WATER mass correlation analysis cluster analysis
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Application of Surface Water Quality Classification Models Using Principal Components Analysis and Cluster Analysis 被引量:2
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作者 Mohamed Ahmed Reda Hamed 《Journal of Geoscience and Environment Protection》 2019年第6期26-41,共16页
Water quality monitoring has one of the highest priorities in surface water protection policy. Many variety approaches are being used to interpret and analyze the concealed variables that determine the variance of obs... Water quality monitoring has one of the highest priorities in surface water protection policy. Many variety approaches are being used to interpret and analyze the concealed variables that determine the variance of observed water quality of various source points. A considerable proportion of these approaches are mainly based on statistical methods, multivariate statistical techniques in particular. In the present study, the use of multivariate techniques is required to reduce the large variables number of Nile River water quality upstream Cairo Drinking Water Plants (CDWPs) and determination of relationships among them for easy and robust evaluation. By means of multivariate statistics of principal components analysis (PCA), Fuzzy C-Means (FCM) and K-means algorithm for clustering analysis, this study attempted to determine the major dominant factors responsible for the variations of Nile River water quality upstream Cairo Drinking Water Plants (CDWPs). Furthermore, cluster analysis classified 21 sampling stations into three clusters based on similarities of water quality features. The result of PCA shows that 6 principal components contain the key variables and account for 75.82% of total variance of the study area surface water quality and the dominant water quality parameters were: Conductivity, Iron, Biological Oxygen Demand (BOD), Total Coliform (TC), Ammonia (NH3), and pH. However, the results from both of FCM clustering and K-means algorithm, based on the dominant parameters concentrations, determined 3 cluster groups and produced cluster centers (prototypes). Based on clustering classification, a noted water quality deteriorating as the cluster number increased from 1 to 3. However the cluster grouping can be used to identify the physical, chemical and biological processes creating the variations in the water quality parameters. This study revealed that multivariate analysis techniques, as the extracted water quality dominant parameters and clustered information can be used in reducing the number of sampling parameters on the Nile River in a cost effective and efficient way instead of using a large set of parameters without missing much information. These techniques can be helpful for decision makers to obtain a global view on the water quality in any surface water or other water bodies when analyzing large data sets especially without a priori knowledge about relationships between them. 展开更多
关键词 SURFACE WATER Principal COMPONENT analysis cluster analysis
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Chinese family care patterns of childhood rheumatic diseases:A cluster analysis 被引量:2
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作者 Jiali Ma Qinglin Yu +1 位作者 Taomei Zhang Ying Zhang 《International Journal of Nursing Sciences》 CSCD 2020年第1期41-48,共8页
Objectives:The purpose is to distinguish family care(FC)patterns of childhood rheumatic diseases in Chinese families and to determine the predictors of FC patterns.Methods:This secondary analysis contained two cross-s... Objectives:The purpose is to distinguish family care(FC)patterns of childhood rheumatic diseases in Chinese families and to determine the predictors of FC patterns.Methods:This secondary analysis contained two cross-section surveys with a convenient sample of totally 398 caregivers who have a child with rheumatic diseases from four pediatric hospitals.Caregivers were required to completed Family Management Measure questionnaire.Cluster analysis was used to distinguish patterns and multinomial logistic regression analysis was used to find predictors.Results:Four patterns were identified:the normal-perspective and collaborative(28.4%),the effortless and contradictory(24.6%),the chaotic and strenuous(18.3%),and the confident and concerning(28.7%).Disease category(x2=21.23,P=0.002),geographic location(x2=8.41,P=0,038),maternal educational level(x2=12.69,P=0.048)and family monthly income(x2=33.21,P<0.001)predicted different patterns.Conclusions:FC patterns were different among families.Disease-related and family-related factors were vital predictors to distinguish patterns consistent with the Family Management Style Framework.The result assisted that clinicians recognize FC patterns and predictors effectively to provide tailored advice in time. 展开更多
关键词 CHILD cluster analysis CROSS-SECTIONAL studies Family caREGIVERS PEDIATRIC hospitals RHEUMATIC diseases
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Fault Detection Based on Hierarchical Cluster Analysis in Wide Area Backup Protection System 被引量:2
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作者 Yagang ZHANG Jinfang ZHANG +1 位作者 Jing MA Zengping WANG 《Energy and Power Engineering》 2009年第1期21-27,共7页
In wide area backup protection of electric power systems, the prerequisite of protection device's accurate, fast and reliable performance is its corresponding fault type and fault location can be discriminated qui... In wide area backup protection of electric power systems, the prerequisite of protection device's accurate, fast and reliable performance is its corresponding fault type and fault location can be discriminated quickly and defined exactly. In our study, global information will be introduced into the backup protection system. By analyzing and computing real-time PMU measurements, basing on cluster analysis theory, we are using mainly hierarchical cluster analysis to search after the statistical laws of electrical quantities' marked changes. Then we carry out fast and exact detection of fault components and fault sections, and finally accomplish fault isolation. The facts show that the fault detection of fault component (fault section) can be performed successfully by hierarchical cluster analysis and calculation. The results of hierarchical cluster analysis are accurate and reliable, and the dendrograms of hierarchical cluster analysis are in intuition. 展开更多
关键词 WIDE area BACKUP protection PHASOR MEASUREMENT unit PMU WIDE area MEASUREMENT system WAMS fault detection cluster analysis
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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 闫敏慧 姚秀萍 +2 位作者 王蕾 姜丽霞 张金峰 《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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Mathematical Tools of Cluster Analysis 被引量:9
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作者 Peter Trebuna Jana Halcinova 《Applied Mathematics》 2013年第5期814-816,共3页
The paper deals with cluster analysis and comparison of clustering methods. Cluster analysis belongs to multivariate statistical methods. Cluster analysis is defined as general logical technique, procedure, which allo... The paper deals with cluster analysis and comparison of clustering methods. Cluster analysis belongs to multivariate statistical methods. Cluster analysis is defined as general logical technique, procedure, which allows clustering variable objects into groups-clusters on the basis of similarity or dissimilarity. Cluster analysis involves computational procedures, of which purpose is to reduce a set of data on several relatively homogenous groups-clusters, while the condition of reduction is maximal and simultaneously minimal similarity of clusters. Similarity of objects is studied by the degree of similarity (correlation coefficient and association coefficient) or the degree of dissimilarity-degree of distance (distance coefficient). Methods of cluster analysis are on the basis of clustering classified as hierarchical or non-hierarchical methods. 展开更多
关键词 cluster analysis Hierarchical cluster analysis Methods Non-Hierarchical cluster analysis Methods
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The Bio-Geographical Regions Division of Global Terrestrial Animal by Multivariate Similarity Clustering Analysis Method 被引量:1
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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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Regional Allocation of CO_2 Intensity Reduction Targets Based on Cluster Analysis 被引量:9
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作者 YANG Yuan CAI Wen-Jia +1 位作者 WANG Can WANG Si-Qiang 《Advances in Climate Change Research》 SCIE 2012年第4期220-228,共9页
To meet China's CO2 intensity target of 40%-45% reduction by 2020 based on the 2005 level,a regional allocation method based on cluster analysis is developed.Thirty Chinese provinces are classified into six groups... To meet China's CO2 intensity target of 40%-45% reduction by 2020 based on the 2005 level,a regional allocation method based on cluster analysis is developed.Thirty Chinese provinces are classified into six groups based on economy,emissions,and reduction potential indicators.Under the equity principle,the two most developed groups are assigned the highest reduction targets(55% and 65%,respectively).However,their reduction potential is limited.Under the efficiency principle,the two groups with the highest reduction potential take the highest targets(48% and 61%,respectively),but their economy is relatively backward.When equity and efficiency are equally weighted,the 5th group with a prominent reduction potential takes the highest target(54%),and the 2nd and the 3rd groups with large industry scales take the second highest target(49%).However,under all the three allocation schemes,the targets are not greater than 40% for the 4th and the 6th groups,which have a relatively low economic ability,emissions,and reduction potential.Due to inconsistency between economic and reduction potential,corresponding market mechanisms and policy instruments should be established to ensure equity and efficiency of regional target allocation. 展开更多
关键词 碳排放强度 分配方案 二氧化碳 聚类分析 减排 经济能力 中国市场 还原电位
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Application of cluster analysis to preventive maintenance scheme design of pavement 被引量:4
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作者 曾峰 张肖宁 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第4期581-586,共6页
To quantitatively identify the maintenance demand for each highway segments in the pavement maintenance scheme design,a mathematical model of uniform segment division was established and an approach of applying cluste... To quantitatively identify the maintenance demand for each highway segments in the pavement maintenance scheme design,a mathematical model of uniform segment division was established and an approach of applying cluster analysis theory to the uniform segment division and evaluation of pavement maintenance demand was proposed.The actual maintenance project of a highway carried out in Guangdong province was cited as an example to demonstrate the validity of the proposed method.It is proved that the cluster analysis can eliminate human factors in classification without being constrained by the quantities of samples,considering multiple pavement distress indexes and the continuity of samples.Thus it is evident that cluster analysis is an efficient analytical tool in uniform segment division and evaluation of maintenance demand. 展开更多
关键词 维修方案 聚类分析 路面养护 设计 预防性 应用 统一数学模型 公路项目
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Application of PP cluster method in the earthquake swarm analysis
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作者 周仕勇 朱令人 邓传玲 《Acta Seismologica Sinica(English Edition)》 CSCD 1995年第3期387-397,共11页
ApplicationofPPclustermethodintheearthquakeswarmanalysisShi-YongZHOU;(周仕勇)Ling-RenZHU;(朱令人)andChuan-LingDENG... ApplicationofPPclustermethodintheearthquakeswarmanalysisShi-YongZHOU;(周仕勇)Ling-RenZHU;(朱令人)andChuan-LingDENG(邓传玲)(Seismologic... 展开更多
关键词 EARTHQUAKE SWARM XINJIANG PP cluster analysis characteristic parameters
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