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Correlation analysis of PCB and comparison of test-analysis model reduction methods
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作者 Xu Fei Li Chuanri +1 位作者 Jiang Tongmin Rong Shuanglong 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2014年第4期835-845,共11页
The validity of correlation analysis between finite element model(FEM) and modal test data is strongly affected by three factors, i.e., quality of excitation and measurement points in modal test,FEM reduction method... The validity of correlation analysis between finite element model(FEM) and modal test data is strongly affected by three factors, i.e., quality of excitation and measurement points in modal test,FEM reduction methods, and correlation check techniques. A new criterion based on modified mode participation(MMP) for choosing the best excitation point is presented. Comparison between this new criterion and mode participation(MP) criterion is made by using Case 1 with a simple printed circuit board(PCB). The result indicates that this new criterion produces better results. In Case 2, 35 measurement points are selected to perform modal test and correlation analysis while 9 selected in Case 3.System equivalent reduction expansion process(SEREP), modal assurance criteria(MAC), coordinate modal assurance criteria(CoMAC), pseudo orthogonality check(POC) and coordinate orthogonality check(CORTHOG) are used to show the error introduced by modal test in Cases 2 and 3. Case 2 shows that additional errors which cannot be identified by using CoMAC can be found by using CORTHOG.In both Cases 2 and 3, Guyan reduction, improved reduced system(IRS) method, SEREP and Hybrid reduction are compared for accuracy and robustness. The results suggest that the quality of the reduction process is problem dependent. However, the IRS method is an improvement over the Guyan reduction, and the Hybrid reduction is an improvement over the SEREP reduction. 展开更多
关键词 correlation analysis Excitation and measurementpoint Finite element method Modal analysis Model reduction PCB
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Evaluation of Comprehensive Performance of Agronomic Traits of Anmai 1241 by Grey Correlation Analysis and Cluster Analysis Methods
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作者 Yong HAN Zhiwei XUE Chunling YANG 《Agricultural Biotechnology》 CAS 2021年第3期44-47,70,共5页
The agronomic traits of the new wheat variety Anmai 1241 were comprehensively evaluated,in order to provide comprehensive and objective theoretical basis for further improvement and production utilization of this vari... The agronomic traits of the new wheat variety Anmai 1241 were comprehensively evaluated,in order to provide comprehensive and objective theoretical basis for further improvement and production utilization of this variety.The winter water production test results of Anmai 1241 in 14 pilot sites of Henan Seed Management Station from 2016 to 2017 were summarized.The comprehensive performance of 11 agronomic traits of Anmai 1241 in different tests sites in Henan Province was evaluated by the grey correlation analysis and clustering analysis methods.The results showed that among the observed values of 11 traits,the variation coefficient,correlation degree and weight of black embryo rate were 181.64%,0.6679 and 0.1051,respectively.The clustering analysis showed that the 11 traits could be divided into 3 groups.The first type of traits(yield,number of grains per ear and 1000-grain weight)and the third group of traits(percentage of earbearing tillers,number of productive tillers and volume weight)belonged to the yield factor traits,and the sum of their weights was 0.5242.Yield and its related factors played an important role in the variety evaluation of Anmai 1241,and the effect of black embryo on yield should be eliminated in variety improvement. 展开更多
关键词 Grey correlation analysis clustering analysis Anmai 1241 Variety evaluation
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Correlation and Cluster Analysis on the Quality Characters of New Middle-ripe Japonica Rice Varieties in Jiangsu Province
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作者 Guoyong ZHU Mingfa SUN +2 位作者 Guohong YAN Chongxiao HE Linsheng WAN 《Agricultural Biotechnology》 CAS 2013年第3期22-24,29,共4页
[ Objective] This study aimed to analyze the quality characteristics of the new middle-ripejapon/ca rico varieties in Jiangsu Province. [ Method] Four- teen new rice varieties included in the Middle-ripe Japon/ca Rice... [ Objective] This study aimed to analyze the quality characteristics of the new middle-ripejapon/ca rico varieties in Jiangsu Province. [ Method] Four- teen new rice varieties included in the Middle-ripe Japon/ca Rice Regional Test in 2011 were selected as the materials. Correlation analysis and cluster analysis were carried out on their quality traits. [Result] The rice cultivars possessed stable characteristics, which were difficult to be further improved. In addition, their quality traits had extremely complicated relationships, and the differences were significant between different groups. [ Conclusion] This study will provide reference for improving the quality traits of japonica rice. 展开更多
关键词 Middle-ripe japonica rice New variety Quality traits correlation Cluster analysis
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A Research on Competitiveness of Guangxi City——Based on System Clustering Method and Principal Component Analysis Method
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作者 FAN Chang-ke WU Yu 《Asian Agricultural Research》 2010年第2期13-16,共4页
A total of 10 indices of regional economic development in Guangxi are selected.According to the relevant economic data,regional economic development in Guangxi is analyzed by using System Clustering Method and Princip... A total of 10 indices of regional economic development in Guangxi are selected.According to the relevant economic data,regional economic development in Guangxi is analyzed by using System Clustering Method and Principal Component Analysis Method.Result shows that System Clustering Method and Principal Component Analysis Method have revealed similar results analysis of economic development level.Overall economic strength of Guangxi is weak and Nanning has relatively high scores of factors due to its advantage of the political,economic and cultural center.Comprehensive scores of other regions are all lower than 1,which has big gap with the development of Nanning.Overall development strategy points out that Guangxi should accelerate the construction of the Ring Northern Bay Economic Zone,create a strong logistics system having strategic significance to national development,use the unique location advantage and rely on the modern transportation system to establish a logistics center and business center connecting the hinterland and the Asean Market.Based on the problems of unbalanced regional economic development in Guangxi,we should speed up the development of service industry in Nanning,construct the circular economy system of industrial city,and accelerate the industrialization process of tourism city in order to realize balanced development of regional economy in Guangxi,China. 展开更多
关键词 clustering analysis Method Factor analysis Method Economic development level Economic strength China
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Correlation Analysis of Turbidity and Total Phosphorus in Water Quality Monitoring Data
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作者 Wenwu Tan Jianjun Zhang +7 位作者 Xing Liu Jiang Wu Yifu Sheng Ke Xiao Li Wang Haijun Lin Guang Sun Peng Guo 《Journal on Big Data》 2023年第1期85-97,共13页
At present,water pollution has become an important factor affecting and restricting national and regional economic development.Total phosphorus is one of the main sources of water pollution and eutrophication,so the p... At present,water pollution has become an important factor affecting and restricting national and regional economic development.Total phosphorus is one of the main sources of water pollution and eutrophication,so the prediction of total phosphorus in water quality has good research significance.This paper selects the total phosphorus and turbidity data for analysis by crawling the data of the water quality monitoring platform.By constructing the attribute object mapping relationship,the correlation between the two indicators was analyzed and used to predict the future data.Firstly,the monthly mean and daily mean concentrations of total phosphorus and turbidity outliers were calculated after cleaning,and the correlation between them was analyzed.Secondly,the correlation coefficients of different times and frequencies were used to predict the values for the next five days,and the data trend was predicted by python visualization.Finally,the real value was compared with the predicted value data,and the results showed that the correlation between total phosphorus and turbidity was useful in predicting the water quality. 展开更多
关键词 correlation analysis CLUSTER water quality predict water quality monitoring data
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A precise tidal prediction mechanism based on the combination of harmonic analysis and adaptive network-based fuzzy inference system model 被引量:6
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作者 ZHANG Zeguo YIN Jianchuan +2 位作者 WANG Nini HU Jiangqiang WANG Ning 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第11期94-105,共12页
An efficient and accurate prediction of a precise tidal level in estuaries and coastal areas is indispensable for the management and decision-making of human activity in the field wok of marine engineering. The variat... An efficient and accurate prediction of a precise tidal level in estuaries and coastal areas is indispensable for the management and decision-making of human activity in the field wok of marine engineering. The variation of the tidal level is a time-varying process. The time-varying factors including interference from the external environment that cause the change of tides are fairly complicated. Furthermore, tidal variations are affected not only by periodic movement of celestial bodies but also by time-varying interference from the external environment. Consequently, for the efficient and precise tidal level prediction, a neuro-fuzzy hybrid technology based on the combination of harmonic analysis and adaptive network-based fuzzy inference system(ANFIS)model is utilized to construct a precise tidal level prediction system, which takes both advantages of the harmonic analysis method and the ANFIS network. The proposed prediction model is composed of two modules: the astronomical tide module caused by celestial bodies’ movement and the non-astronomical tide module caused by various meteorological and other environmental factors. To generate a fuzzy inference system(FIS) structure,three approaches which include grid partition(GP), fuzzy c-means(FCM) and sub-clustering(SC) are used in the ANFIS network constructing process. Furthermore, to obtain the optimal ANFIS based prediction model, large numbers of simulation experiments are implemented for each FIS generating approach. In this tidal prediction study, the optimal ANFIS model is used to predict the non-astronomical tide module, while the conventional harmonic analysis model is used to predict the astronomical tide module. The final prediction result is performed by combining the estimation outputs of the harmonious analysis model and the optimal ANFIS model. To demonstrate the applicability and capability of the proposed novel prediction model, measured tidal level samples of Fort Pulaski tidal station are selected as the testing database. Simulation and experimental results confirm that the proposed prediction approach can achieve precise predictions for the tidal level with high accuracy, satisfactory convergence and stability. 展开更多
关键词 tidal level prediction harmonious analysis method adaptive network-based fuzzy inference system correlation analysis
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Reliability Distribution of Numerical Control Lathe Based on Correlation Analysis 被引量:3
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作者 Xiaoyan Qi Guixiang Shen +2 位作者 Yingzhi Zhang Shuguang Sun Bingkun Chen 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第5期32-38,共7页
Combined Reliability distribution with correlation analysis,a new method has been proposed to make Reliability distribution where considering the elements about structure correlation and failure correlation of subsyst... Combined Reliability distribution with correlation analysis,a new method has been proposed to make Reliability distribution where considering the elements about structure correlation and failure correlation of subsystems.Firstly,we make a sequence for subsystems by means of TOPSIS which comprehends the considerations of Reliability allocation,and introducing a Copula connecting function to set up a distribution model based on structure correlation,failure correlation and target correlation,and then acquiring reliability target area of all subsystems by Matlab.In this method,not only the traditional distribution considerations are concerned,but also correlation influences are involved,to achieve supplementing information and optimizing distribution. 展开更多
关键词 RELIABILITY DISTRIBUTION correlation analysis TOPSIS method COPULA connecting FUNCTION
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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
On the basis of mixture theory of concentration of Helland-Hansen (Mao et al, 1964; Helland-Hansen, 1916), this paper takes salinity as a conservative factor in the process of dilution and mixture and selects by relat... On the basis of mixture theory of concentration of Helland-Hansen (Mao et al, 1964; Helland-Hansen, 1916), this paper takes salinity as a conservative factor in the process of dilution and mixture and selects by relating analysis the bydrological and chemical factors which are closely related to salinity. Then making use of the Q type multi-dimensions cluster analysis, we get the results that the water masses in the western Taiwan Strait include the follying: the coastal water along Fujian, Zhejiang and Guangdong Provinces, the diluted fresh water of Minjiang, Jiulong and Hanjiang Rivers; the mixing water in the Taiwan Strait; upwelling cold/warm water to the northwest of the Taiwan Shoal and the upwelling water to the east of Guangdong. The mixing weter in the Taiwan Strait during spring and summer is composed of a Kuroshio branch, the surface weter of the South China Sea, outal wier along Fujian, Zhejiang and Guangdong Provinces. While in autunm and winter, it is mixed up from Kuroshio branch, the shelf weter in the East China Sea, and the coastal water along Fujian, Zhejiang and Guangdong. There is an obvious seasonal change of growth and decline in these water masses. 展开更多
关键词 The western Taiwan Strait water mass correlation analysis cluster analysis
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Source analysis and risk evaluation of heavy metal in the river sediment of polymetallic mining area:Taking the Tonglüshan skarn type Cu-Fe-Au deposit as an example,Hubei section of the Yangtze River Basin,China 被引量:5
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作者 Jing Wang Xin-xin Zhang +5 位作者 Ai-fang Chen Bo Wang Qi-bin Zhao Guan-nan Liu Xiao Xiao Jin-nan Cao 《China Geology》 CAS 2022年第4期649-661,共13页
In this paper,25 sampling points of overlying deposits in Tonglushan mining area,Daye City,Hubei Province,China were tested for heavy metal content to explore pollution characteristics,pollution sources and ecological... In this paper,25 sampling points of overlying deposits in Tonglushan mining area,Daye City,Hubei Province,China were tested for heavy metal content to explore pollution characteristics,pollution sources and ecological risks of heavy metals in sediments.A geo-accumulation index method was used to evaluate the degree of heavy metal pollution in the sediment.The mean sediment quality guideline quotient was used for evaluating the ecological risk level of heavy metal in the sediment.And a method of correlation analysis,clustering analysis,and principal component analysis was used for preliminary analysis on the source of heavy metal in the sediment.It was indicated that there was extremely heavy metal pollution in the sediment,among which Cd was extremely polluted,Cu strongly contaminated,Zn,As,and Hg moderately contaminated,and Pb,Cr,and Ni were slightly contaminated.It was also indicated by the mean sediment quality guideline-quotient result that there was a high ecological risk of heavy metals in the sediment,and 64%of the sample sites had extremely high hidden biotoxic effects.For distribution,the contamination of branches was worse than that of the main channel of Daye Dagang,and the deposition of each heavy metal was mainly influenced by the distance from this sample site to the sewage draining exit of a tailings pond.The source analysis showed that the heavy metals in the sediment come from pollution discharging of mining and beneficiation companies,tailings ponds,smelting companies,and transport vehicles.In the study area,due to the influence of heavy metal discharging from these sources,the ecotoxicity of heavy metals in the sediment was extremely high,and Cd was the most toxic pollutant.The research figured out the key restoration area and elements for ecological restoration in the sediment of the Tonglüshan mining area,which could be referenced by monitoring and governance of heavy metal pollution in the sediment of the polymetallic mining area. 展开更多
关键词 Sediment Heavy metal pollution Ecological risks Geo-accumulation index method Sediment quality guideline-quotient Cluster analysis Principal component analysis Skarn-type Ecological environment survey Tonglüshan Daye Lake China
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Correlation and Path Coefficient and Chi-square Distance Cluster Analysis for Several Characteristics in Tobacco Germplasm Resource 被引量:1
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作者 LI Wenping ZHU Lieshu +3 位作者 ZHAO Songyi LIANG Qizheng WANG Yuchao TAN Xi 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第1期10-15,共6页
Correlation and path coefficient analyses were conducted for 10 characteristics of 24 pure lines of flue-cured tobacco such as plant height, knot distance, leaf number, the central leaf length and width, ratio of the ... Correlation and path coefficient analyses were conducted for 10 characteristics of 24 pure lines of flue-cured tobacco such as plant height, knot distance, leaf number, the central leaf length and width, ratio of the length to width, stem girth, dates of budding, leaf yield and ratio of the prime-medium tobacco. The leaf number and the central leaf length showed a positive or a strong positive correlation with the yield per plant. And the leaf number and leaf yield per plant showed a strong positive correlation with the ratio of prime-medium tobacco. The results showed that the leaf yield per plant among these characteristics played a major role in determining the ratio of prime-medium tobacco while the others were less related with the ratio. Square sum of deviation method cluster analyses showed that 24 pure lines of flue-cured tobacco were clustered into two groups. Of the pure lines, Line T1706 and Line T1245 had a far relationship with all other lines, and also had a heterosis when crossed with the other lines. Lines Guangdonghuang 1 and R72(3)B-2-1 were closely related. 展开更多
关键词 flue-cured tobacco correlation analysis path coefficient analysis cluster analysis
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Analysis of the Influence Factors of Grain Supply-Demand Gap in China 被引量:2
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作者 Bingjun Li Weiming Yang 《Agricultural Sciences》 2018年第7期901-909,共9页
Based on the analysis of the grain supply and demand gap’s current situation in China, this paper establishes an indicator system for the influence factors of grain supply and demand gap. Then this paper calculates t... Based on the analysis of the grain supply and demand gap’s current situation in China, this paper establishes an indicator system for the influence factors of grain supply and demand gap. Then this paper calculates the correlation degree between the main grain varieties’ supply and demand gap and its influence factors. The results show that sown area and unit yield have the greatest impact on wheat supply and demand gap;per capita disposable income and unit yield have the greatest impact on corn supply and demand gap;per capita disposable income and agricultural mechanization level have the greatest impact on the supply and demand gap of soybean and rice. From the analysis results, we can obtain the difference between the factors affecting the grain supply and demand gap, and provide a certain theoretical basis and new ideas for the balance of grain supply and demand in China. 展开更多
关键词 ENTROPY Method GREY correlation analysis DEMand and Supply GAP Influence FACTORS
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Correlations between direct and indirect strength test methods 被引量:6
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作者 Kallu Raj Roghanchi Pedram 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第3期355-360,共6页
The difficulties associated with performing direct compression strength tests on rocks lead to the development of indirect test methods for the rock strength assessment. Indirect test methods are simple, more economic... The difficulties associated with performing direct compression strength tests on rocks lead to the development of indirect test methods for the rock strength assessment. Indirect test methods are simple, more economical, less time-consuming, and easily adaptable to the field. The main aim of this study was to derive correlations between direct and indirect test methods for basalt and rhyolite rock types from Carlin trend deposits in Nevada. In the destructive methods, point load index, block punch index, and splitting tensile strength tests are performed. In the non-destructive methods, Schmidt hammer and ultrasonic pulse velocity tests are performed. Correlations between the direct and indirect compression strength tests are developed using linear and nonlinear regression analysis methods. The results show that the splitting tensile strength has the best correlation with the uniaxial compression strength.Furthermore, the Poisson's ratio has no correlation with any of the direct and indirect test results. 展开更多
关键词 Uniaxial compression strength test Indirect strength test methods correlation Regression 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 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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Photometric solution and period analysis of the contact binary system AH Cnc 被引量:1
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作者 Ying-Jiang Peng Zhi-Quan Luo +11 位作者 Xiao-Bin Zhang Li-Cai Deng Kun Wang Jian-Feng Tian Zheng-Zhou Yan Yang Pan Wei-Jing Fang Zhong-Wen Feng De-Lin Tang Qi-Li Liu Jin-Jiang Sun Qiang Zhou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第10期63-70,共8页
Photometric observations of AH Cnc, a W UMa-type system in the open cluster M67, were car- fled out by using the 50BIN telescope. About 100h of time-series/3- and V-band data were taken, based on which eight new times... Photometric observations of AH Cnc, a W UMa-type system in the open cluster M67, were car- fled out by using the 50BIN telescope. About 100h of time-series/3- and V-band data were taken, based on which eight new times of light minima were determined. By applying the Wilson-Devinney method, the light curves were modeled and a revised photometric solution of the binary system was derived. We con- firmed that AH Cnc is a deep contact (f = 51%), low mass-ratio (q - 0.156) system. Adopting the distance modulus derived from study of the host cluster, we have re-calculated the physical parameters of the binary system, namely the masses and radii. The masses and radii of the two components were estimated to be respectively 1.188(4-0.061) Me, 1.332(4-0.063) RQ for the primary component and 0.185(4-0.032) Me, 0.592(4-0.051) Re for the secondary. By adding the newly derived minimum timings to all the available data, the period variations of AH Cnc were studied. This shows that the orbital period of the binary is con- tinuously increasing at a rate of dp/dt = 4.29 x 10-10 d yr-1. In addition to the long-term period increase, a cyclic variation with a period of 35.26 yr was determined, which could be attributed to an unresolved tertiary component of the system. 展开更多
关键词 methods data analysis -- astronomical instrumentation -- binaries: eclipsing stars closestars -- Galaxy: open clusters and associations: individual (M67)
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Screening of Long Cowpea[Vigna unguiculata(L.)Walp.ssp.sesquipedialis]Varieties in Autumn in Hunan and Comparison of Various Comprehensive Evaluation Methods 被引量:1
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作者 Lin HUANG Zhibing CHEN +6 位作者 Wan JIANG Xincheng SUN Zhongwu ZHANG Jie KANG Lianyong YANG Weiping CHEN Yuanqun PENG 《Plant Diseases and Pests》 2024年第5期33-39,共7页
[Objectives]The paper was to screen new varieties of long cowpea that are suitable for autumn cultivation in Hunan,as well as to develop a comprehensive evaluation method to assess their adaptability and performance.[... [Objectives]The paper was to screen new varieties of long cowpea that are suitable for autumn cultivation in Hunan,as well as to develop a comprehensive evaluation method to assess their adaptability and performance.[Methods]A total of 48 long cowpea varieties were introduced,and a range of comprehensive evaluation methods was employed to assess these varieties through the collection and analysis of field data.[Results]The square Euclidean distance of 14 allowed for the classification of all varieties into eight distinct groups.Groups II,III,and V belong to the autumn dominant group within this region,while groups I and VIII belong to the intermediate group.Additionally,groups IV,VI,and VII belong to the autumn inferior group in this area.Through a comparative analysis of various comprehensive evaluation methods,it was determined that the common factor comprehensive evaluation,grey correlation method,and fuzzy evaluation method were appropriate for application in the selection of long cowpea varieties.Furthermore,the evaluation outcomes were largely consistent with the cluster pedigree diagram.[Conclusions]Through comprehensive index method,ten varieties demonstrating superior performance in autumn cultivation have been identified,including C20,C42,C29,C40,C3,C14,C18,C25,C15,and C47.The selected varieties exhibit several advantageous traits,such as a reduced growth duration,a lower position of initial flower nodes,a decreased number of branches,predominantly green young pods,elongated pod strips,thicker pod structures,an increased number of pods per plant,and higher overall yields.These characteristics render them particularly valuable for extensive cultivation. 展开更多
关键词 Long cowpea Variety SCREENING Cluster analysis Comprehensive evaluation method
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Growing correlation length of moderate-sized earthquakes prior to two great earthquakes near Sumatra Island 被引量:2
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作者 Rong Dailu Li Yarong 《Geodesy and Geodynamics》 2012年第3期29-33,共5页
Seismic correlation length for moderate earthquakes prior to two great earthquakes in the northern sea area of Sumatra Island (Mw9.1 in 2004 and MsS. 6 in 2012) has been studied, using method of Single- Link-Cluster... Seismic correlation length for moderate earthquakes prior to two great earthquakes in the northern sea area of Sumatra Island (Mw9.1 in 2004 and MsS. 6 in 2012) has been studied, using method of Single- Link-Cluster ( SLC ) analysis, and found to show a power-law growth about two years before their occurrences. No such growth was found for a magnitude 7 earthquake in the same area. This result suggests the occurrence of a physical process of critical-point characteristics in the source area before the great earthquakes. 展开更多
关键词 northern sea area of Sumatra Island earthquake critical-point characteristics seismic spatial- correlation length single-link cluster analysis SLC
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Correlation Study on Grain Size Characteristics and Geotechnical Properties of Surface Sediments in Qingdao Offshore Area
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作者 LI Anlong WANG Panpan +5 位作者 GUO Xijun JI Xiangkun SHEN Kunming LIN Lin YAN Zhichao YUAN Lin 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期721-730,共10页
The comprehension of sediment grain size parameters and the corresponding sedimentary environment holds paramount importance in elucidating the engineering geological attributes of the subaqueous seabed.This study del... The comprehension of sediment grain size parameters and the corresponding sedimentary environment holds paramount importance in elucidating the engineering geological attributes of the subaqueous seabed.This study delineated the sedimentary environment zoning in the northern sea area of Qingdao through cluster analysis of grain size parameters derived from 123 surface sediment samples.The study analyzed the correlation between sediment geotechnical indices and grain size parameters across diverse sedimentary environments.A correlation equation was established for samples exhibiting a strong correlation.The study found four distinct sedimentary environments in the study area:coastal,transitional,shallow sea,and residual.Within the same sedimentary environment,the average grain size and sorting coefficient exhibit significant correlations with geotechnical indices such as water content,density,shear strength,plastic limit,liquid limit,and plastic index.However,notable disparities in the correlation between grain size parameters and geotechnical indices emerge across different sedimentary environments. 展开更多
关键词 grain size parameters cluster analysis sedimentary environment correlationS geotechnical indexes
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Analysis of Factors Influencing Comprehensive Productivity of Agriculture in Henan Province on the Basis of Grey Correlation
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作者 YAN Chao-de XIAO Hong-an 《Asian Agricultural Research》 2011年第10期6-10,共5页
According to the data from Henan Statistical Yearbook from 2002 to 2008, from production capital, production conditions, labour inputs and financial support, this paper selects 11 variables influencing comprehensive p... According to the data from Henan Statistical Yearbook from 2002 to 2008, from production capital, production conditions, labour inputs and financial support, this paper selects 11 variables influencing comprehensive productivity of agriculture in Henan Province. Through calculation and analysis of grey correlation of variables and comprehensive productivity of agriculture, this paper determines the impact of different variables on comprehensive productivity of agriculture. The results show that the agricultural capital has become the most important factor influencing comprehensive productivity of agriculture in Henan Province, while the impact of production conditions, labour inputs and financial support on comprehensive productivity of agriculture in Henan Province diminishes in turn. Corresponding countermeasures and suggestions are put forward to promote the sustainable development of comprehensive productivity of agriculture in Henan Province as follows: strengthen agricultural financial system building, and ensure agricultural production expenditure; scientifically arrange allocation of agricultural resources, and improve agricultural production conditions; carry out training of agricultural skills, and elevate the quality of agricultural labour forces; increase financial expenditure for agricultural production, and optimize financial expenditure structure. 展开更多
关键词 Comprehensive productivity of agriculture Grey correlation analysis method Influencing factors Henan Province China
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Transverse flowmetry of carbon particles based on photoacoustic Doppler standard deviation using an auto-correlation method
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作者 卢涛 孙丽君 《Optoelectronics Letters》 EI 2015年第3期226-228,共3页
In order to measure the flow velocity of carbon particle suspension perpendicular to the receiving axis of ultrasound transducer, the standard deviation of photoacoustic Doppler frequency spectrum is used to estimate ... In order to measure the flow velocity of carbon particle suspension perpendicular to the receiving axis of ultrasound transducer, the standard deviation of photoacoustic Doppler frequency spectrum is used to estimate the bandwidth broadening, and the spectrum standard deviation is calculated by an auto-correlation method. A 532 nm pulsed laser with the repetition rate of 20 Hz is used as a pumping source to generate photoacoustic signal. The photoacoustic signals are detected using a focused PZT ultrasound transducer with the central frequency of 10 MHz. The suspension of carbon particles is driven by a syringe pump. The complex photoacoustic signal is calculated by Hilbert transformation from time domain signal before auto-correlation. The standard deviation of the Doppler bandwidth broadening is calculated by averaging the auto-correlation results of several individual A scans. The feasibility of the proposed method is demonstrated by measuring the spectrum standard deviation of the transversal carbon particle flow from 5.0 mm/s to 8.4 mrn/s. The experimental results show that the auto-correlation result is approximately linearly distributed within the measuring range. 展开更多
关键词 BandWIDTH Carbon correlation methods Flow velocity Mathematical transformations Optical pumping Pumping (laser) STATISTICS Time domain analysis Transducers Ultrasonic propagation Ultrasonic scattering Ultrasonic transducers
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Quantitative analysis of urban intelligence and ranking the potential of individual initiatives within a designed smart growth plan
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作者 MA Yun-long CHEN Xu LUO Song 《Ecological Economy》 2017年第1期69-79,共11页
Smart growth has been gaining increasing attention among academia and practitioners as a new technology-based solution to meet the city disease challenges.In the research,we mainly accomplish two tasks.One builds an e... Smart growth has been gaining increasing attention among academia and practitioners as a new technology-based solution to meet the city disease challenges.In the research,we mainly accomplish two tasks.One builds an evaluation system to measure the smart growth of a city.And the other develops a growth plan.Firstly,coordination coefficient(C value) model is applied to measure the smart degree.To begin with,we divide the indicators into four aspects which involve five parameters.Then,entropy method is used to calculate the weight of every parameter.After normalizing data of indicators,we set up a smart growth indicator evaluation system.Aiming to assessing the detailed performances,we rank the eight cities according to the score of C value which corresponds to our normal cognition.Secondly,based on Salvo combat model and dynamic trend analysis model,We draw up a 20-year growth plan with a period of 5 years for the two cities we choose.The Salvo model is adopted to describe the dynamic process.Dynamic trend analysis model is introduced to gain the optimum solution and the optimal point in every stage.In addition,compared with the point of every stage,we can obtain the proportion of investment in different stages.Thirdly,to evaluate the sensitivity of our model with the OFAT Method,we adjust the parameters k_1,k_2 and O_(ij) approximately.It comes out that the change of k_1,k_2 and O_(ij) has an impact on the C value.But the sensitivity of k_1,k_2 is higher.Lastly,we analyze the influence caused by population growth.To a certain extent,it can be concluded that the plan we made can alleviate the negative impact of population growth through the analysis of the chart. 展开更多
关键词 entropy method coordination coefficient Salvo combat model dynamic trend analysis smart degree correlation analysis
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