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Group decision-making method based on entropy and experts cluster analysis 被引量:12
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作者 Xuan Zhou Fengming Zhang Xiaobin Hui Kewu Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第3期468-472,共5页
According to the aggregation method of experts' evaluation information in group decision-making,the existing methods of determining experts' weights based on cluster analysis take into account the expert's preferen... According to the aggregation method of experts' evaluation information in group decision-making,the existing methods of determining experts' weights based on cluster analysis take into account the expert's preferences and the consistency of expert's collating vectors,but they lack of the measure of information similarity.So it may occur that although the collating vector is similar to the group consensus,information uncertainty is great of a certain expert.However,it is clustered to a larger group and given a high weight.For this,a new aggregation method based on entropy and cluster analysis in group decision-making process is provided,in which the collating vectors are classified with information similarity coefficient,and the experts' weights are determined according to the result of classification,the entropy of collating vectors and the judgment matrix consistency.Finally,a numerical example shows that the method is feasible and effective. 展开更多
关键词 group decision-making judgment matrix ENTROPY information similarity coefficient cluster 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... 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-Aeari 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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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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The Fuzzy Cluster Analysis in Identification of Key Temperatures in Machine Tool
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作者 ZHAO Da-quan 1, ZHENG Li 1, XIANG Wei-hong 1, LI Kang 1, LIU Da-cheng 1, ZHANG Bo-peng 2 (1. Department of Industrial Engineering, Tsinghua University, 2. Department of Precision Instruments and Mechanology, Tsinghua University, B eijing 100084, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期88-89,共2页
The thermal-induced error is a very important sour ce of machining errors of machine tools. To compensate the thermal-induced machin ing errors, a relationship model between the thermal field and deformations was need... The thermal-induced error is a very important sour ce of machining errors of machine tools. To compensate the thermal-induced machin ing errors, a relationship model between the thermal field and deformations was needed. The relationship can be deduced by virtual of FEM (Finite Element Method ), ANN (Artificial Neural Network) or MRA (Multiple Regression Analysis). MR A is on the basis of a total understanding of the temperature distribution of th e machine tool. Although the more the temperatures measured are, the more accura te the MRA is, too more temperatures will hinder the analysis calculation. So it is necessary to identify the key temperatures of the machine tool. The selectio n of key temperatures decides the efficiency and precision of MRA. Because of th e complexities and multi-input and multi-output structure of the relationships , the exact quantitative portions as well as the unclear portions must be taken into consideration together to improve the identification of key temperatures. I n this paper, a fuzzy cluster analysis was used to select the key temperatures. The substance of identifying the key temperatures is to group all temperatures b y their relativity, and then to select a temperature from each group as the repr esentation. A fuzzy cluster analysis can uncover the relationships between t he thermal field and deformations more truly and thoroughly. A fuzzy cluster ana lysis is the cluster analysis based on fuzzy sets. Given U={u i|i=0,...,N}, in which u i is the temperature measured, a fuzzy matrix R can be obta ined. The transfer close package t(R) can be deduced from R. A fuzzy clu ster of U then conducts on the basis of t(R). Based on the fuzzy cluster analysis discussed above, this paper identified the k ey temperatures of a horizontal machining center. The number of the temperatures measured was reduced to 4 from 32, and then the multiple regression relationshi p models between the 4 temperatures and the thermal deformations of the spindle were drawn. The remnant errors between the regression models and measured deform ations reached a satisfying low level. At the same time, the decreasing of tempe rature variable number improved the efficiency of measure and analysis greatly. 展开更多
关键词 The Fuzzy cluster analysis in Identification of Key Temperatures in Machine Tool
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Multi-affinity clustering analysis based graph learning for multichannel signal utilization
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作者 WANG Zhicheng JIANG Huiming +2 位作者 XU Hui SUN Gao SHENG Jialian 《Journal of Systems Engineering and Electronics》 2026年第1期171-183,共13页
Multichannel signals have the characteristics of information diversity and information consistency.To better explore and utilize the affinity relationship within multichannel signals,a new graph learning technique bas... Multichannel signals have the characteristics of information diversity and information consistency.To better explore and utilize the affinity relationship within multichannel signals,a new graph learning technique based on low rank tensor approximation is proposed for multichannel monitoring signal processing and utilization.Firstly,the affinity relationship of multichannel signals can be acquired based on the clustering results of each channel signal.Wherein an affinity tensor is constructed to integrate the diverse and consistent information of the clustering information among multichannel signals.Secondly,a low-rank tensor optimization model is built and the joint affinity matrix is optimized with the assistance of the strong confidence affinity matrix.Through solving the optimization model,the fused affinity relationship graph of multichannel signals can be obtained.Finally,the multichannel fused clustering results can be acquired though the updated joint affinity relationship graph.The multichannel signal utilization examples in health state assessment with public datasets and microwave detection with actual echoes verify the advantages and effectiveness of the proposed method. 展开更多
关键词 clustering analysis multichannel signals health state assessment target recognition
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Genetic Diversity of Gray Leaf Spot Pathogen on Dictamnus dasycarpus in Heilongjiang Province
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作者 Zhang Junhua Ren Rui +8 位作者 Yang Xin Tian Ziyu Zhao Guohui Han Songhan Zhang Yifei Wu Jiaju Xu Xiaofeng Ni Zhe Yang Mingxiu 《Journal of Northeast Agricultural University(English Edition)》 2026年第1期1-10,共10页
To ascertain the genetic diversity of gray leaf spot pathogen on Dictamnus dasycarpus popoulation in Heilongjiang Province,a total of 57 strains of Paracercospora dictamnicola were isolated and purified from the disea... To ascertain the genetic diversity of gray leaf spot pathogen on Dictamnus dasycarpus popoulation in Heilongjiang Province,a total of 57 strains of Paracercospora dictamnicola were isolated and purified from the diseased samples collected from five Chinese herbal medicine planting areas in Heilongjiang Province between the years of 2021 and 2022.Repetitive extragenic palindromic polymerase chain reaction(Rep–PCR)was used to amplify 57 isolates of gray leaf spot pathogen on D.dasycarpus from different regions of Heilongjiang Province.The polymorphic bands amplified by three sets of primers accounted for more than 80%.Cluster analysis results showed that at a similarity coefficient of 0.67,the gray leaf spot pathogen on D.dasycarpus in Heilongjiang Province could be divided into five major genetic groups.Genetic diversity parameter analysis indicated that there were certain differences in genetic richness among the geographic populations of gray leaf spot pathogen on D.dasycarpus from different regions.Analysis of molecular variance(AMOVA)revealed that genetic variation among strains mainly originated within populations.The genetic differentiation and relationships of gray leaf spot pathogen on D.dasycarpus from different geographic regions of Heilongjiang Province indicated that genetic differentiation and kinship among populations were somewhat related to their geographic distance.The greater the geographic distance,the higher the genetic differentiation coefficient,and the lower the genetic uniformity among populations. 展开更多
关键词 genetic diversity gray leaf spot repetitive extragenic palindromic polymerase chain reaction(Rep-PCR) cluster analysis analysis of molecular variance
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Genetic Diversity Analysis of Aneurolepidium chinense(Trin)Kitag by ISSR Marker
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作者 YIN Zhi LI Chengyan +1 位作者 LI Hechun HU Guofu 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第2期55-59,共5页
In the study,the reasonable sampling of the grey Aneurolepidium chinense of green grassland,the grey-greenA chinense of green grassland,the grey A.chinense of Wulimu and the grey-green A.chinense of Wulimu were analyz... In the study,the reasonable sampling of the grey Aneurolepidium chinense of green grassland,the grey-greenA chinense of green grassland,the grey A.chinense of Wulimu and the grey-green A.chinense of Wulimu were analyzed by ISSR.Eight primers with clear and diverse products were sereened out from 20 primers and 47 DNA fragments were ampli ed from 39individuals.The average number of DNA fragments produced by each primer was 5.9,and polymorphic bands were 41 and thepolymorphic rate was 87.23%,which could re ect the genetic variation that was with four plots of each kind and to the individuals.Chuster results showed that at rst,the grey A chinense of Wulimu and the grey-green A chinense of Wulimu were grouped together,and then they grouped with the grey A chinense of green grassland into one chuster,at last with the grey-green A.chinense of greengrassland.A.chinense of identical symusiologic type was grouped together.According to Shannon index,the green grassland of thegrey A chinense had the largest variation degree,which indicated that A.chinense had vaniation among species and interspecies byISSR analysis,but A.chinense didn't differentiate different species. 展开更多
关键词 Aneurolepidium chinense(Trin)Kitag ISSR genetic variation cluster analysis
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Deceptive jamming suppression in multistatic radar based on coherent clustering 被引量:14
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作者 ABDALLA Ahmed AHMED Mohaned Giess Shokrallah +2 位作者 ZHAO Yuan XIONG Ying TANG Bin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第2期269-277,共9页
This paper proposes a suppression method of the deceptive false target(FT) produced by digital radio frequency memory(DRFM) in a multistatic radar system. The simulated deceptive false targets from DRFM cannot be easi... This paper proposes a suppression method of the deceptive false target(FT) produced by digital radio frequency memory(DRFM) in a multistatic radar system. The simulated deceptive false targets from DRFM cannot be easily discriminated and suppressed with traditional radar systems. Therefore, multistatic radar has attracted considerable interest as it provides improved performance against deception jamming due to several separated receivers. This paper first investigates the received signal model in the presence of multiple false targets in all receivers of the multistatic radar. Then, obtain the propagation time delays of the false targets based on the cross-correlation test of the received signals in different receivers. In doing so, local-density-based spatial clustering of applications with noise(LDBSCAN) is proposed to discriminate the FTs from the physical targets(PTs) after compensating the FTs time delays, where the FTs are approximately coincident with one position, while PTs possess small dispersion.Numerical simulations are carried out to demonstrate the feasibility and validness of the proposed method. 展开更多
关键词 multistatic radar clustering analysis electronic counter-countermeasure(ECCM) deceptive jamming
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Kernel method-based fuzzy clustering algorithm 被引量:2
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作者 WuZhongdong GaoXinbo +1 位作者 XieWeixin YuJianping 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第1期160-166,共7页
The fuzzy C-means clustering algorithm(FCM) to the fuzzy kernel C-means clustering algorithm(FKCM) to effectively perform cluster analysis on the diversiform structures are extended, such as non-hyperspherical data, d... The fuzzy C-means clustering algorithm(FCM) to the fuzzy kernel C-means clustering algorithm(FKCM) to effectively perform cluster analysis on the diversiform structures are extended, such as non-hyperspherical data, data with noise, data with mixture of heterogeneous cluster prototypes, asymmetric data, etc. Based on the Mercer kernel, FKCM clustering algorithm is derived from FCM algorithm united with kernel method. The results of experiments with the synthetic and real data show that the FKCM clustering algorithm is universality and can effectively unsupervised analyze datasets with variform structures in contrast to FCM algorithm. It is can be imagined that kernel-based clustering algorithm is one of important research direction of fuzzy clustering analysis. 展开更多
关键词 fuzzy clustering analysis kernel method fuzzy C-means clustering.
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RAPD analysis on the four kinds of color-flowered Salvia splendens Ker-Gawl 被引量:1
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作者 HU Guofu YUAN Qiang LI Fenglan WEI Qi HU Baozhong 《Journal of Northeast Agricultural University(English Edition)》 CAS 2007年第2期97-102,共6页
In this study, we used RAPD to analyze four kinds of color-flowered Salvia splendens Ker-Gawl, and the optimal RAPD reaction conditions were the optimal reaction mixture (25 μL total volume) that contained 2.0 μL ... In this study, we used RAPD to analyze four kinds of color-flowered Salvia splendens Ker-Gawl, and the optimal RAPD reaction conditions were the optimal reaction mixture (25 μL total volume) that contained 2.0 μL 10×buffer, 0.45 mmol·L^-1 dNTPs, 2.0 mmol· L^-1 Mg^2+, 2 U Taq DNA polymerase, 0.30 umol·L^-2 primer and 40 ng genomic DNA. Total 84 bands were amplified from 12 primers used, and the differential bands had 28 bands, which was 33% of total bands. In cluster group analysis, the four kinds of color-flowered were divided into two styles. One style is that the red color and red-white color were grouped together, then they grouped with purple color into one cluster, and the white color was another style. 展开更多
关键词 Salvia splendens Ker-Gawl COLOR RAPD analysis cluster group analysis
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Ant colony ATTA clustering algorithm of rock mass structural plane in groups
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作者 李夕兵 王泽伟 +1 位作者 彭康 刘志祥 《Journal of Central South University》 SCIE EI CAS 2014年第2期709-714,共6页
Based on structural surface normal vector spherical distance and the pole stereographic projection Euclidean distance,two distance functions were established.The cluster analysis of structure surface was conducted by ... Based on structural surface normal vector spherical distance and the pole stereographic projection Euclidean distance,two distance functions were established.The cluster analysis of structure surface was conducted by the use of ATTA clustering methods based on ant colony piles,and Silhouette index was introduced to evaluate the clustering effect.The clustering analysis of the measured data of Sanshandao Gold Mine shows that ant colony ATTA-based clustering method does better than K-mean clustering analysis.Meanwhile,clustering results of ATTA method based on pole Euclidean distance and ATTA method based on normal vector spherical distance have a great consistence.The clustering results are most close to the pole isopycnic graph.It can efficiently realize grouping of structural plane and determination of the dominant structural surface direction.It is made up for the defects of subjectivity and inaccuracy in icon measurement approach and has great engineering value. 展开更多
关键词 rock mass discontinuity cluster analysis ant colony ATTA algorithm distance function Silhouette index
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New judging model of fuzzy cluster optimal dividing based on rough sets theory
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作者 Wang Yun Liu Qinghong +1 位作者 Mu Yong Shi Kaiquan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第2期392-397,共6页
To investigate the judging problem of optimal dividing matrix among several fuzzy dividing matrices in fuzzy dividing space, correspondingly, which is determined by the various choices of cluster samples in the totali... To investigate the judging problem of optimal dividing matrix among several fuzzy dividing matrices in fuzzy dividing space, correspondingly, which is determined by the various choices of cluster samples in the totality sample space, two algorithms are proposed on the basis of the data analysis method in rough sets theory: information system discrete algorithm (algorithm 1) and samples representatives judging algorithm (algorithm 2). On the principle of the farthest distance, algorithm 1 transforms continuous data into discrete form which could be transacted by rough sets theory. Taking the approximate precision as a criterion, algorithm 2 chooses the sample space with a good representative. Hence, the clustering sample set in inducing and computing optimal dividing matrix can be achieved. Several theorems are proposed to provide strict theoretic foundations for the execution of the algorithm model. An applied example based on the new algorithm model is given, whose result verifies the feasibility of this new algorithm model. 展开更多
关键词 Rough sets theory Fuzzy optimal dividing matrix Representatives of samples Fuzzy cluster analysis Information system approximate precision.
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Weighting indicators of building energy efficiency assessment taking account of experts' priority 被引量:10
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作者 杨玉兰 邰惠鑫 施韬 《Journal of Central South University》 SCIE EI CAS 2012年第3期803-808,共6页
Analytic hierarchy process(Group AHP) is combined with two different methods of assigning experts' priority to weight indicators in building energy efficiency assessment.One is to assign the experts' priority ... Analytic hierarchy process(Group AHP) is combined with two different methods of assigning experts' priority to weight indicators in building energy efficiency assessment.One is to assign the experts' priority averagely,and the other is to use cluster analysis to assign experts' priority.The results show that,1) Different expert's priority assigns result in great different weights of indicators in building energy efficiency assessment,therefore,the method of assigning experts' priority should be taken into account carefully while weighting indicators of building energy efficiency assessment using Group AHP;2) Three indicators are found to be overwhelmingly important in residential building energy efficiency assessment in the hot summer and cold winter zone in China.They are 'Outdoor & indoor shadow','Heating & air-conditioning facilities' and 'Insulation of envelope';3) The method combining cluster analysis with Group AHP to weight indicator of building energy efficiency assessment has the advantage of finding overwhelming important indicator,whereas,some less important indicators have a tendency to be ignored.A useful reference is provided for building energy conservation including policy revision and energy efficient residential building design. 展开更多
关键词 energy efficiency BUILDING weighting cluster analysis analytic hierarchy process
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Screening and evaluation of reliable traits of upland cotton(Gossypium hirsutum L.)genotypes for salt tolerance at the seedling growth stage 被引量:9
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作者 SIKDER Ripon Kumar WANG Xiangru +6 位作者 JIN Dingsha ZHANG Hengheng GUI Huiping DONG Qiang PANG Nianchang ZHANG Xiling SONG Meizhen 《Journal of Cotton Research》 2020年第2期90-102,共13页
Background:Salt stress significantly inhibits the growth,development,and productivity of cotton because of osmotic,ionic,and oxidative stresses.Therefore,the screening and development of salt tolerant cotton cultivars... Background:Salt stress significantly inhibits the growth,development,and productivity of cotton because of osmotic,ionic,and oxidative stresses.Therefore,the screening and development of salt tolerant cotton cultivars is a key issue towards sustainable agriculture.This study subjected 11 upland cotton genotypes at the seedling growth stage to five different salt concentrations and evaluated their salt tolerance and reliable traits.Results:Several morpho-physiological traits were measured after 10 days of salinity treatment and the salt tolerance performance varied significantly among the tested cotton genotypes.The optimal Na Cl concentration for the evaluation of salt tolerance was 200 mmol·L-1.Membership function value and salt tolerance index were used to identify the most consistent salt tolerance traits.Leaf relative water content and photosynthesis were identified as reliable indicators for salt tolerance at the seedling stage.All considered traits related to salt tolerance indices were significantly and positively correlated with each other except for malondialdehyde.Cluster heat map analysis based on the morpho-physiological salt tolerance-indices clearly discriminated the 11 cotton genotypes into three different salt tolerance clusters.Cluster I represented the salt-tolerant genotypes(Z9807,Z0228,and Z7526)whereas clusters II(Z0710,Z7514,Z1910,and Z7516)and III(Z0102,Z7780,Z9648,and Z9612)represented moderately salttolerant and salt-sensitive genotypes,respectively.Conclusions:A hydroponic screening system was established.Leaf relative water content and photosynthesis were identified as two reliable traits that adequately represented the salt tolerance of cotton genotypes at the seedling growth stage.Furthermore,three salt-tolerant genotypes were identified,which might be used as genetic resources for the salt-tolerance breeding of cotton. 展开更多
关键词 Cotton genotypes Salt stress Screening Membership function value cluster analysis
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Combining ability of Egyptian cotton(Gossypium barbadense L.)reveals genetic potential for improved yield and fiber quality 被引量:1
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作者 Abdelghany Ahmed M. El-Banna Aly A.A. +5 位作者 Lamlom Sobhi F El-Sorady Gawhara A. Salama Ehab A.A. Ren Honglei Shaibu Abdulwahab S. Yehia Waleed M.B. 《Journal of Cotton Research》 CAS 2024年第2期109-122,共14页
Background As the most widely cultivated fiber crop,cotton production depends on hybridization to unlock the yield potential of current varieties.A deep understanding of genetic dissection is crucial for the cultivati... Background As the most widely cultivated fiber crop,cotton production depends on hybridization to unlock the yield potential of current varieties.A deep understanding of genetic dissection is crucial for the cultivation of enhanced hybrid plants with desired traits,such as high yield and fine fiber quality.In this study,the general combining ability(GCA)and specific combining ability(SCA)of yield and fiber quality of nine cotton parents(six lines and three testers)and eighteen F1 crosses produced using a line×tester mating design were analyzed.Results The results revealed significant effects of genotypes,parents,crosses,and interactions between parents and crosses for most of the studied traits.Moreover,the effects of both additive and non-additive gene actions played a notably significant role in the inheritance of most of the yield and fiber quality attributes.The F1 hybrids of(Giza 90×Aust)×Giza 86,Uzbekistan 1×Giza 97,and Giza 96×Giza 97 demonstrated superior performance due to their favorable integration of high yield attributes and premium fiber quality characteristics.Path analysis revealed that lint yield has the highest positive direct effect on seed cotton yield,while lint percentage showed the highest negative direct effect on seed cotton yield.Principal component analysis identified specific parents and hybrids associated with higher cotton yield,fiber quality,and other agronomic traits.Conclusion This study provides insights into identifying potential single-and three-way cross hybrids with superior cotton yield and fiber quality characteristics,laying a foundation for future research on improving fiber quality in cotton. 展开更多
关键词 Gossypium barbadense L. Combining ability Seed cotton yield Fiber quality cluster analysis Path analysis
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The Processing of Parts with Group Technology in Individual CNC Machining Center
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作者 GONG Bing-zhou (Faculty of Engineering, Ningbo University, Ningbo 315211, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期154-155,共2页
This paper proposes a new machining method for part s using group technology suitable for workshop condition in China. The method divi des the parts of each product into similar kinds according to their features, an d... This paper proposes a new machining method for part s using group technology suitable for workshop condition in China. The method divi des the parts of each product into similar kinds according to their features, an d installs each kind of parts on different working platforms. The working platfo rm, as a unit, is designed to be flexible and is interchangeable. It can be hung and fitted to the CNC working table. By changing the platforms in turn, nearly all the parts of one product can be processed with one CNC machine, and can be s ent directly to an assembly shop. Thus the number of management links is reduced and the production rate is increased. Several working platforms may be needed w hen several different types of parts are being processed. However, to reduce pro duction costs, it is necessary to limit the similarity coefficient of part class ification. The feature-coding classification is better for processing parts wit h this method. A practical classification code made by the author is for plastic injection machines. As an example, ten numbers (0~9) are used to express the d i fferent functions and the main features of the parts in the first code-rank. An insufficient classification may be offset by applying cut store and adjusting f unctions to the processing program in the CNC machine center, thereby allowing a set of parts which are not completely similar to be processed on a single worki ng platform. Before a set of parts with incompletely similar features is machine d on a working platform, it is necessary to plan reasonable technological proces s, for which we adopted an optimum method aimed to shorten the working period so as to increase production rate. The fixture planning for this processing method is also discussed in this paper. Modular fixture is recommended for mounting a set of parts on a working platform. In general, modular fixture has a basic boar d and a set of disassemble locating and clamping elements. Because the working p latform can be used directly as the main locating datum, it is unnecessary to de sign another basic board. However, if a working platform is to be used for diffe rent sets of parts, it is better to design it as a dowel-pin series basic board . 展开更多
关键词 working platform coding classification cluster analysis fixture planning
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Classification and Genetic Diversity of Kentucky Bluegrasses by Using RAPD Markers
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作者 LIANG Min GAO Lina +1 位作者 CHEN Yajun ZHANG Xueyan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2009年第4期9-13,共5页
Total 69 random primers were screened out through RAPD (Random Amplified Polymorphic DNA) markers to analyze the genetic bands of 32 Kentucky bluegrass cultivars. A total of 197 bands were amplified from 46 primers ... Total 69 random primers were screened out through RAPD (Random Amplified Polymorphic DNA) markers to analyze the genetic bands of 32 Kentucky bluegrass cultivars. A total of 197 bands were amplified from 46 primers of them, among which 195 bands were polymorphic. Each primer could amplify one to nine polymorphic bands with an average of 4.3 being amplified from an average of primer. Based on the similarity coefficient analysis of RAPD results, NTSYS software and cluster analysis by using average UPGMA method, the result showed that 18 of 32 cultivars were in group 1, three cultivars were in group 2, two cultivars were in group 3, eight cultivars were in group 4, and there was only one cultivar in group 5, which was C2. 展开更多
关键词 Kentucky bluegrass RAPD genetic diversity cluster analysis
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RAPD Anlysis of Different Leaf Colour in Euphorbia pulcherrima
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作者 BAI Haina NIU De WANG Lijuan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2009年第2期32-36,共5页
Random amplified polymorphic DNA (RAPD) was used to study the diversity of seven E. pulcherrima with different color leaves. Aight 10 bp primers selected from 30 arbitrary primers were applied for amplifying the Eup... Random amplified polymorphic DNA (RAPD) was used to study the diversity of seven E. pulcherrima with different color leaves. Aight 10 bp primers selected from 30 arbitrary primers were applied for amplifying the Euphorbia pulcherrima DNA. Total 62 bands were produced, among which 22 bands (35.48%) were polymorphic. The average numbers of polymorphic DNA bands amplified by each primer were 7.8. Cluster analysis results showed that the genetic background of seven E. pulcherrima was relatively narrow and they had the higher similarity coefficient, which indicated that these seven strains had a near relationship, and that RAPD marking technology may be the effective means for E. pulcherrima classification. 展开更多
关键词 E. pulcherrima RAPD cluster analysis
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Experimental Research on Influence of Some Factors on Ejection Height of Cargo Projectile
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作者 郁浩 王晓天 +1 位作者 李欣 李纪敏 《Defence Technology(防务技术)》 CAS 2012年第1期16-20,共5页
Some factors influencing the cargo projectile's ejection height in different conditions were analyzed by using harmonic curve diagram and cluster method.The test results of the ejection height for a certain cargo ... Some factors influencing the cargo projectile's ejection height in different conditions were analyzed by using harmonic curve diagram and cluster method.The test results of the ejection height for a certain cargo projectile show that the wind speed and direction are the main influence factors.For given meteorological conditions,the applied environmental stress becomes the main cause,while the launching angle does not influence the ejection height. 展开更多
关键词 mathematical statistics ejection height harmonic curve diagram cluster analysis cargo projectile
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胃蝇属三龄幼虫形态特征及行为的种间和种内关系分析 被引量:4
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作者 刘善辉 胡德夫 +1 位作者 李凯 范晓泽 《中国兽医杂志》 CAS 北大核心 2018年第6期3-7,共5页
以胃蝇属6个种(黑腹胃蝇、黑角胃蝇、鼻胃蝇、肠胃蝇、红尾胃蝇、裸节胃蝇)三龄幼虫为研究对象,借助于2010年9月-2016年9月期间获取的数据,研究其种间和种内形态学特征及行为方式的遗传差异,为研究其适应宿主体内寄生生活机制提供依据... 以胃蝇属6个种(黑腹胃蝇、黑角胃蝇、鼻胃蝇、肠胃蝇、红尾胃蝇、裸节胃蝇)三龄幼虫为研究对象,借助于2010年9月-2016年9月期间获取的数据,研究其种间和种内形态学特征及行为方式的遗传差异,为研究其适应宿主体内寄生生活机制提供依据。结果表明,胃蝇三龄幼虫种间在体长、体宽、体重、体长/体宽和蠕动频率、爬行速度、入土深度及入土时间上均表达显著水平,且三龄幼虫形态种间和种内都存在着丰富的遗传变异。胃蝇属三龄幼虫种间变异率入土深度(25. 25%)>爬行速度(25. 09%)>蠕动频率(24. 60%)>体重(22. 75%)>入土时间(20. 75%)>体长/体宽(19. 16%)>三龄幼虫体宽(13. 95%)>三龄幼虫体长(13. 03%)。在形态及特征与行为方式相关性上,三龄幼虫体长与爬行速度和入土深度分别呈显著负相关和极显著负相关;体宽与蠕动频率呈显著正相关;体长/体宽与入土时间呈显著正相关,与蠕动频率和爬行速度分别呈极显著负相关和显著负相关关系;体重与爬行速度及入土深度分别呈极显著负相关和显著负相关关系。根据形态特征和行为方式指标将胃蝇属6个种划分为3类,肠胃蝇、红尾胃蝇和裸节胃蝇三支聚集成为一簇,黑腹胃蝇分支单独形成一簇,鼻胃蝇和黑角胃蝇分支形成第三簇。 展开更多
关键词 胃蝇属 形态特征 表观遗传 行为方式 聚类分析
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