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Upper Bounds on the Multicolor Ramsey Numbers r_(k)(C_(4))
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作者 Tian-yu LI Qi-zhong LIN 《Acta Mathematicae Applicatae Sinica》 2025年第1期286-294,共9页
The multicolor Ramsey number r_(k)(C_(4))is the smallest integer N such that any k-edge coloring of KN contains a monochromatic C_(4).The current best upper bound of r_(k)(C_(4))was obtained by Chung(1974)and independ... The multicolor Ramsey number r_(k)(C_(4))is the smallest integer N such that any k-edge coloring of KN contains a monochromatic C_(4).The current best upper bound of r_(k)(C_(4))was obtained by Chung(1974)and independently by Irving(1974),i.e.,r_(k)(C_(4))≤k^(2)+k+1 for all k≥2.There is no progress on the upper bound since then.In this paper,we improve the upper bound of r_(k)(C_(4))by showing that r_(k)(C_(4))≤k^(2)+k-1 for even k≥6.The improvement is based on the upper bound of the Turan number ex(n,C4),in which we mainly use the double counting method and many novel ideas from Firke,Kosek,Nash,and Williford[J.Combin.Theory,Ser.B 103(2013),327-336]. 展开更多
关键词 Multicolor Ramsey number Turan number 4-cycle
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关联Bernoulli数与Stirling数、Eulerian数的恒等式
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作者 唐军强 《山西师范大学学报(自然科学版)》 2024年第4期1-5,共5页
自然数的幂和公式可以用Bernoulli数、两类Stirling数和Eulerian数分别表示.这些常数之间一定存在着某种关联,将后两者公式中关于n的组合数用第一类Stirling数的升阶乘定义展开,将所得结果与雅各布·伯努利公式中关于n的各幂次的系... 自然数的幂和公式可以用Bernoulli数、两类Stirling数和Eulerian数分别表示.这些常数之间一定存在着某种关联,将后两者公式中关于n的组合数用第一类Stirling数的升阶乘定义展开,将所得结果与雅各布·伯努利公式中关于n的各幂次的系数进行比较,得到了关联Bernoulli数和两类Stirling数及Eulerian数的恒等式. 展开更多
关键词 自然数方幂和 BERNOULLI数 第一类stirling 第二类stirling Eulerian数
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An Equation of Stirling Numbers of the Second Kind 被引量:3
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作者 DU Chun-yu ZHANG Jian-guo 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第2期261-263,共3页
In this paper, We propose and prove the following equation, where {3^n} is a stirling number of the second kind, when n ≥ 3 is given.
关键词 COMBINATIONS stirling numbers of the second kind
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Partial Bell Polynomials, Falling and Rising Factorials, Stirling Numbers, and Combinatorial Identities
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作者 Siqintuya Jin Bai-Ni Guo Feng Qi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第9期781-799,共19页
In the paper,the authors collect,discuss,and find out several connections,equivalences,closed-form formulas,and combinatorial identities concerning partial Bell polynomials,falling factorials,rising factorials,extende... In the paper,the authors collect,discuss,and find out several connections,equivalences,closed-form formulas,and combinatorial identities concerning partial Bell polynomials,falling factorials,rising factorials,extended binomial coefficients,and the Stirling numbers of the first and second kinds.These results are new,interesting,important,useful,and applicable in combinatorial number theory. 展开更多
关键词 Connection EQUIVALENCE closed-form formula combinatorial identity partial Bell polynomial falling factorial rising factorial binomial coefficient stirling number of the first kind stirling number of the second kind problem
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Operator Formulas Involving Generalized Stirling Number Derived by Virtue of Normal Ordering of Vacuum Projector
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作者 范洪义 姜年权 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第10期651-653,共3页
By virtue of the normal ordering of vacuum projector we directly derive some new complicated operatoridentities, regarding to the generalized Stirling number.
关键词 operator formulas generalized stirling number normal operator
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Quantum mechanical operator realization of the Stirling numbers theory studied by virtue of the operator Hermite polynomials method
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作者 范洪义 楼森岳 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期102-105,共4页
Based on the operator Hermite polynomials method(OHPM), we study Stirling numbers in the context of quantum mechanics, i.e., we present operator realization of generating function formulas of Stirling numbers with s... Based on the operator Hermite polynomials method(OHPM), we study Stirling numbers in the context of quantum mechanics, i.e., we present operator realization of generating function formulas of Stirling numbers with some applications.As a by-product, we derive a summation formula involving both Stirling number and Hermite polynomials. 展开更多
关键词 operator Hermite polynomials method(OHPM) stirling numbers
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A Family of Generalized Stirling Numbers of the First Kind
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作者 Beih S. El-Desouky Nabela A. El-Bedwehy +1 位作者 Abdelfattah Mustafa Fatma M. Abdel Menem 《Applied Mathematics》 2014年第10期1573-1585,共13页
A modified approach via differential operator is given to derive a new family of generalized Stirling numbers of the first kind. This approach gives us an extension of the techniques given by El-Desouky?[1]?and Gould?... A modified approach via differential operator is given to derive a new family of generalized Stirling numbers of the first kind. This approach gives us an extension of the techniques given by El-Desouky?[1]?and Gould?[2]. Some new combinatorial identities and many relations between different types of Stirling numbers are found. Furthermore, some interesting special cases of the generalized Stirling numbers of the first kind are deduced. Also, a connection between these numbers and the generalized harmonic numbers is derived. Finally, some applications in coherent states and matrix representation of some results obtained are given. 展开更多
关键词 stirling numberS Comtet numberS CREATION ANNIHILATION Differential Operator MAPLE Program
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Generalized Legendre-Stirling Numbers
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作者 K. C. Garrett Kendra Killpatrick 《Open Journal of Discrete Mathematics》 2014年第4期109-114,共6页
The Legendre-Stirling numbers were discovered by Everitt, Littlejohn and Wellman in 2002 in a study of the spectral theory of powers of the classical second-order Legendre differential operator. In 2008, Andrews and L... The Legendre-Stirling numbers were discovered by Everitt, Littlejohn and Wellman in 2002 in a study of the spectral theory of powers of the classical second-order Legendre differential operator. In 2008, Andrews and Littlejohn gave a combinatorial interpretation of these numbers in terms of set partitions. In 2012, Mongelli noticed that both the Jacobi-Stirling and the Legendre-Stirling numbers are in fact specializations of certain elementary and complete symmetric functions and used this observation to give a combinatorial interpretation for the generalized Legendre-Stirling numbers. In this paper we provide a second combinatorial interpretation for the generalized Legendre-Stirling numbers which more directly generalizes the definition of Andrews and Littlejohn and give a combinatorial bijection between our interpretation and the Mongelli interpretation. We then utilize our interpretation to prove a number of new identities for the generalized Legendre-Stirling numbers. 展开更多
关键词 stirling numberS Legendre-stirling numberS SET PARTITIONS
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On Polynomials Rn(x) Related to the Stirling Numbers and the Bell Polynomials Associated with the p-Adic Integral on
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作者 Hui Young Lee Cheon Seoung Ryoo 《Open Journal of Discrete Mathematics》 2016年第2期89-98,共10页
In this paper, one introduces the polynomials R<sub>n</sub>(x) and numbers R<sub>n</sub> and derives some interesting identities related to the numbers and polynomials: R<sub>n</sub>... In this paper, one introduces the polynomials R<sub>n</sub>(x) and numbers R<sub>n</sub> and derives some interesting identities related to the numbers and polynomials: R<sub>n</sub> and R<sub>n</sub>(x). We also give relation between the Stirling numbers, the Bell numbers, the R<sub>n</sub> and R<sub>n</sub>(x). 展开更多
关键词 The Euler numbers and Polynomials The stirling numbers The Bell Polynomials and numbers
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Genome-wide investigation to assess copy number variants in the Italian local chicken population 被引量:1
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作者 Filippo Cendron Martino Cassandro Mauro Penasa 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期563-577,共15页
Background Copy number variants(CNV)hold significant functional and evolutionary importance.Numerous ongoing CNV studies aim to elucidate the etiology of human diseases and gain insights into the population structure ... Background Copy number variants(CNV)hold significant functional and evolutionary importance.Numerous ongoing CNV studies aim to elucidate the etiology of human diseases and gain insights into the population structure of livestock.High-density chips have enabled the detection of CNV with increased resolution,leading to the identification of even small CNV.This study aimed to identify CNV in local Italian chicken breeds and investigate their distribution across the genome.Results Copy number variants were mainly distributed across the first six chromosomes and primarily associated with loss type CNV.The majority of CNV in the investigated breeds were of types 0 and 1,and the minimum length of CNV was significantly larger than that reported in previous studies.Interestingly,a high proportion of the length of chromosome 16 was covered by copy number variation regions(CNVR),with the major histocompatibility complex being the likely cause.Among the genes identified within CNVR,only those present in at least five animals across breeds(n=95)were discussed to reduce the focus on redundant CNV.Some of these genes have been associated to functional traits in chickens.Notably,several CNVR on different chromosomes harbor genes related to muscle development,tissue-specific biological processes,heat stress resistance,and immune response.Quantitative trait loci(QTL)were also analyzed to investigate potential overlapping with the identified CNVR:54 out of the 95 gene-containing regions overlapped with 428 QTL associated to body weight and size,carcass characteristics,egg production,egg components,fat deposition,and feed intake.Conclusions The genomic phenomena reported in this study that can cause changes in the distribution of CNV within the genome over time and the comparison of these differences in CNVR of the local chicken breeds could help in preserving these genetic resources. 展开更多
关键词 CHICKEN Copy number variant CONSERVATION Local breed SNP
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The first factor affecting dryland winter wheat grain yield under various mulching measures: Spike number 被引量:1
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作者 Yingxia Dou Hubing Zhao +4 位作者 Huimin Yang Tao Wang Guanfei Liu Zhaohui Wang Sukhdev Malhi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期836-848,共13页
Water is the key factor limiting dryland wheat grain yield.Mulching affects crop yield and yield components by affecting soil moisture.Further research is needed to determine the relationships between yield components... Water is the key factor limiting dryland wheat grain yield.Mulching affects crop yield and yield components by affecting soil moisture.Further research is needed to determine the relationships between yield components and soil moisture with yield,and to identify the most important factor affecting grain yield under various mulching measures.A long-term 9-yearifeld experiment in the Loess Plateau of Northwest China was carried out with three treatments:no mulch (CK),plastic mulch (M_(P)) and straw mulch (M_(S)).Yield factors and soil moisture were measured,and the relationships between them were explored by correlation analysis,structural equation modeling and significance analysis.The results showed that compared with CK,the average grain yields of M_(P) and M_(S) increased by 13.0and 10.6%,respectively.The average annual grain yield of the M_(P) treatment was 134 kg ha^(–1) higher than the M_(S) treatment.There were no significant differences in yield components among the three treatments (P<0.05).Soil water storage of the M_(S) treatment was greater than the M_(P) treatment,although the differences were not statistically signifiant.Soil water storage during the summer fallow period (SWSSF) and soil water storage before sowing (SWSS) of M_(S) were significantly higher than in CK,which increased by 38.5 and 13.6%,respectively.The relationship between M_(P) and CK was not statistically significant for SWSSF,but the SWSS in M_(P) was significantly higher than in CK.In terms of soil water storage after harvest (SWSH) and water consumption in the growth period(ET),there were no signi?cant differences among the three treatments.Based on the three analysis methods,we found that spike number and ET were positively correlated with grain yield.However,the relative importance of spike number to yield was the greatest in the M_(P )and M_(S) treatments,while that of ET was the greatest in CK.Suifcient SWSSF could indirectly increase spike number and ET in the three treatments.Based on these results,mulch can improve yield and soil water storage.The most important factor affecting the grain yield of dryland wheat was spike number under mulching,and ET with CK.These findings may help us to understand the main factors influencing dryland wheat grain yield under mulching conditions compared to CK. 展开更多
关键词 dryland winter wheat plastic mulch spike number straw mulch
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ASYMPTOTIC APPROXIMATIONS OF R-STIRLING NUMBERS
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作者 C. B. Corcino (1) L. C. Hsu (2) E. L. Tan (1) 《Analysis in Theory and Applications》 1999年第3期13-25,共13页
Using a modified saddle-point method we obtained asymptotic approximation of the r-Stirling numbers of the first and second kind. Here we used a nontrivial trans formation of the same type as that discussed by N.M. Te... Using a modified saddle-point method we obtained asymptotic approximation of the r-Stirling numbers of the first and second kind. Here we used a nontrivial trans formation of the same type as that discussed by N.M. Temme[13], to put the integral representations in volved into a form on which we can apply the saddle point 展开更多
关键词 MATH ASYMPTOTIC APPROXIMATIONS OF R-stirling numberS
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Origin of Sexy Prime Numbers, Origin of Cousin Prime Numbers, Equations from Supposedly Prime Numbers, Origin of the Mersenne Number, Origin of the Fermat Number
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作者 Mady Ndiaye 《Advances in Pure Mathematics》 2024年第5期321-332,共12页
We have found through calculations that the differences between the closest supposed prime numbers other than 2 and 3 defined in the articles are: 2;4: and 6. For those whose difference is equal to 6, we showed their ... We have found through calculations that the differences between the closest supposed prime numbers other than 2 and 3 defined in the articles are: 2;4: and 6. For those whose difference is equal to 6, we showed their origin then we classified them into two categories according to their classes, we showed in which context two prime numbers which differ from 6 are called sexy and in what context they are said real sexy prime. For those whose difference is equal to 4, we showed their origin then we showed that two prime numbers which differ from 4, that is to say two cousin prime numbers, are successive. We made an observation on the supposed prime numbers then we established two pairs of equations from this observation and deduced the origin of the Mersenne number and that of the Fermat number. 展开更多
关键词 Cousin Prime numbers Sexy Prime numbers Real Sexy Prime numbers Equations from Supposed Prime numbers Mersenne number Fermat number Supposed Prime numbers Prime numbers
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The prediction of donor number and acceptor number of electrolyte solvent molecules based on machine learning
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作者 Huaping Hu Yuqing Shan +3 位作者 Qiming Zhao Jinglun Wang Lingjun Wu Wanqiang Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期374-382,共9页
Electrolyte solvents have a critical impact on the design of high performance and safe batteries.Gutmann's donor number(DN) and acceptor number(AN) values are two important parameters to screen and design superior... Electrolyte solvents have a critical impact on the design of high performance and safe batteries.Gutmann's donor number(DN) and acceptor number(AN) values are two important parameters to screen and design superior electrolyte solvents. However, it is more time-consuming and expensive to obtain DN and AN values through experimental measurements. Therefore, it is essential to develop a method to predict DN and AN values. This paper presented the prediction models for DN and AN based on molecular structure descriptors of solvents, using four machine learning algorithms such as Cat Boost(Categorical Boosting), GBRT(Gradient Boosting Regression Tree), RF(Random Forest) and RR(Ridge Regression).The results showed that the DN and AN prediction models based on Cat Boost algorithm possesses satisfactory prediction ability, with R^(2) values of the testing set are 0.860 and 0.96. Moreover, the study analyzed the molecular structure parameters that impact DN and AN. The results indicated that TDB02m(3D Topological distance based descriptors-lag 2 weighted by mass) had a significant effect on DN, while HATS1s(leverage-weighted autocorrelation of lag 1/weighted by I-state) plays an important role in AN. The work provided an efficient approach for accurately predicting DN and AN values, which is useful for screening and designing electrolyte solvents. 展开更多
关键词 Machine learning Donor number Acceptor number Electrolyte solvents
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Preliminary Identification of a Prime Number Other Than 2 and 3, the Origin of Twin Prime Numbers, the Structure of the Chain of Prime Numbers and the Set of Prime Numbers Less Than a Given Integer
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作者 Mady Ndiaye 《Advances in Pure Mathematics》 2024年第1期30-48,共19页
The application of the Euclidean division theorem for the positive integers allowed us to establish a set which contains all the prime numbers and this set we called it set of supposedly prime numbers and we noted it ... The application of the Euclidean division theorem for the positive integers allowed us to establish a set which contains all the prime numbers and this set we called it set of supposedly prime numbers and we noted it E<sub>sp</sub>. We subsequently established from the previous set the set of non-prime numbers (the set of numbers belonging to this set and which are not prime) denoted E<sub>np</sub>. We then extracted from the set of supposedly prime numbers the numbers which are not prime and the set of remaining number constitutes the set of prime numbers denoted E<sub>p</sub>. We have deduced from the previous set, the set of prime numbers between two natural numbers. We have explained during our demonstrations the origin of the twin prime numbers and the structure of the chain of prime numbers. 展开更多
关键词 Supposedly Prime numbers Non-Prime numbers Prime numbers Prime numbers Less Than a Given Integer Prime numbers between Two Given Integers
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On the Number of Primes in the Interval (x, 2x) by an Elementary Method
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作者 Sudhindra B. Kittur 《Advances in Pure Mathematics》 2024年第1期16-29,共14页
An elementary formula to know the number of primes in the interval (x, 2x) close to the exact figure for a fixed x is given here. A new elementary equation is derived (a relation between prime numbers and composite nu... An elementary formula to know the number of primes in the interval (x, 2x) close to the exact figure for a fixed x is given here. A new elementary equation is derived (a relation between prime numbers and composite numbers distributed in the interval [1, 2x]). An elementary method to know the number of primes in a given magnitude is suitably placed in the form of a general formula, and we have proved it. The general formula is applied to the terms of the equation, and a tactical simplification of the terms gives rise to an expression whose verification envisages scope for its further studies. 展开更多
关键词 Prime numbers Composite numbers EXPRESSION INTEGERS
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A novel Effective Panicle Number per Plant 4 haplotype enhances grain yield by coordinating panicle number and grain number in rice
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作者 Yun Wang Xiaoqian Wang +6 位作者 Laiyuan Zhai Sundus Zafar Congcong Shen Shuangbing Zhu Kai Chen Yun Wang Jianlong Xu 《The Crop Journal》 SCIE CSCD 2024年第1期202-212,共11页
Increasing effective panicle number per plant(EPN)is one approach to increase yield potential in rice.However,molecular mechanisms underlying EPN remain unclear.In this study,we integrated mapbased cloning and genome-... Increasing effective panicle number per plant(EPN)is one approach to increase yield potential in rice.However,molecular mechanisms underlying EPN remain unclear.In this study,we integrated mapbased cloning and genome-wide association analysis to identify the EPN4 gene,which is allelic to NARROW LEAF1(NAL1).Overexpression lines containing the Teqing allele(TQ)of EPN4 had significantly increased EPN.NIL-EPN4^(TQ) in japonica(geng)cultivar Lemont(LT)exhibited significantly improved EPN but decreased grain number and flag leaf size relative to LT.Haplotype analysis indicated that accessions with EPN4-1 had medium EPN,medium grain number,and medium grain weight,but had the highest grain yield among seven haplotypes,indicating that EPN4-1 is an elite haplotype of EPN4 for positive coordination of the three components of grain yield.Furthermore,accessions carrying the combination of EPN4-1 and haplotype GNP1-6 of GNP1 for grain number per panicle showed higher grain yield than those with other allele combinations.Therefore,pyramiding of EPN4-1 and GNP1-6 could be a preferred approach to obtain high yield potential in breeding. 展开更多
关键词 RICE Effective panicle number per plant Grain number per panicle HAPLOTYPE Grain yield potential
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How Prime Numbers Are Interconnected and Built with Two Equations: Addition and Subtraction Rules the Function (6µ)
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作者 John Richard Wisdom 《Advances in Pure Mathematics》 2024年第4期228-241,共14页
Are all prime numbers linked by four simple functions? Can we predict when a prime will appear in a sequence of primes? If we classify primes into two groups, Group 1 for all primes that appear before ζ (such that , ... Are all prime numbers linked by four simple functions? Can we predict when a prime will appear in a sequence of primes? If we classify primes into two groups, Group 1 for all primes that appear before ζ (such that , for instance 5, ), an even number divisible by 3 and 2, and Group 2 for all primes that are after ζ (such that , for instance 7), then we find a simple function: for each prime in each group, , where n is any natural number. If we start a sequence of primes with 5 for Group 1 and 7 for Group 2, we can attribute a μ value for each prime. The μ value can be attributed to every prime greater than 7. Thus for Group 1, and . Using this formula, all the primes appear for , where μ is any natural number. 展开更多
关键词 number Theory Prime number Groups Twin Primes Prime Structure and Sequence Prime Subtraction and Addition
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基于决策者偏好构造的概率语言型Z-number多属性决策方法 被引量:1
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作者 王旭婷 毛军军 张新宇 《海南师范大学学报(自然科学版)》 CAS 2024年第2期135-143,共9页
由于决策环境的日益复杂,专家评价信息往往会包含专家偏好,因此有必要对专家偏好进行识别与处理。针对这一情况,提出了基于决策者偏好构造的概率语言型Z-number并应用于多属性决策问题中。首先,针对专家偏好未知的情况,提出了一种基于... 由于决策环境的日益复杂,专家评价信息往往会包含专家偏好,因此有必要对专家偏好进行识别与处理。针对这一情况,提出了基于决策者偏好构造的概率语言型Z-number并应用于多属性决策问题中。首先,针对专家偏好未知的情况,提出了一种基于修正的平均得分距离,由专家评价信息确定专家偏好。然后,依据得到的专家偏好,利用GOWPA算子与最大熵生成概率语言型Z-number。同时,获得专家评价信息的可信度,由专家可信度聚合专家信息并采用TODIM方法对方案进行排序。最后,在国家大力提倡节能减排的背景下,将所提方法应用于国家绿色矿山试点企业的选取上,验证了所提方法的有效性和可行性。 展开更多
关键词 概率语言型Z-number 偏好 GOWPA算子 最大熵 多准则群决策
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The wheat sucrose synthase gene TaSus1 is a determinant of grain number per spike
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作者 Liping Shen Lili Zhang +20 位作者 Changbin Yin Xiaowan Xu Yangyang Liu Kuocheng Shen He Wu Zhiwen Sun Ke Wang Zhonghu He Xueyong Zhang Chenyang Hao Jian Hou Aoyue Bi Xuebo Zhao Daxing Xu Botao Ye Xuchang Yu Ziying Wang Danni Liu Yuanfeng Hao Fei Lu Zifeng Guo 《The Crop Journal》 SCIE CSCD 2024年第1期295-300,共6页
Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight(TGW)in wheat(Triticum aestivum L.).However,no mutations have been identified within the gene to test this association.The e... Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight(TGW)in wheat(Triticum aestivum L.).However,no mutations have been identified within the gene to test this association.The effects of TaSus1 on grain number per spike(GNS)also are largely unknown.Our previous genome-wide association study identified TaSus-A1 as a candidate gene controlling fertile spikelet number per spike(FSN).In the present study,we generated two independent mutants for the three TaSus1 homoeologs by CRISPR/Cas9-mediated genome editing.The triple mutants displayed lower FSN,GNS,grain number per spikelet(GNST),and TGW than wild-type plants.In 306 hexaploid wheat accessions,two single-nucleotide polymorphisms in TaSus-A1 contributed differently to GNS.Introgression of the two alleles into a wheat genetic background confirmed their effects.The alleles differed in geographical distribution among the accessions. 展开更多
关键词 Domestication selection Fertile spikelet number per spike(FSN) Geographical differentiation Grain number per spike(GNS) TaSus1
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