针对汽车总装车间前的涂装车身缓冲区(Painted Body Storage)路由调度问题,结合线性缓冲区的结构特点,本文提出了一种基于两阶段匹配度的PBS路由调度策略。该策略以最大化匹配度为目标,第一阶段针对PBS车身的入库问题,构建了基于车身信...针对汽车总装车间前的涂装车身缓冲区(Painted Body Storage)路由调度问题,结合线性缓冲区的结构特点,本文提出了一种基于两阶段匹配度的PBS路由调度策略。该策略以最大化匹配度为目标,第一阶段针对PBS车身的入库问题,构建了基于车身信息的匹配度模型,采用简单规则集法进行求解;第二阶段针对PBS车身的出库问题,构建了基于生产计划的匹配度模型,通过遗传算法进行求解。最后,通过实例分析验证了该算法的有效性。展开更多
Let G be a simple graph with no isolated vertices. A set S of vertices of G is a total dominating set if every vertex of G is adjacent to some vertex in S . The total domination number of G , den...Let G be a simple graph with no isolated vertices. A set S of vertices of G is a total dominating set if every vertex of G is adjacent to some vertex in S . The total domination number of G , denoted by γ t (G) , is the minimum cardinality of a total dominating set of G . It is shown that if G is a graph of order n with minimum degree at least 3, then γ t (G)≤n/2 . Thus a conjecture of Favaron, Henning, Mynhart and Puech is settled in the affirmative.展开更多
The procedure of stratified double quartile ranked set sampling （SDQRSS） method is introduced to estimate the population mean. The SDQRSS is compared with the simple random sampling （SRS）, stratified ranked set sa...The procedure of stratified double quartile ranked set sampling （SDQRSS） method is introduced to estimate the population mean. The SDQRSS is compared with the simple random sampling （SRS）, stratified ranked set sampling （SRSS） and stratified simple random sampling （SSRS）. It is shown that SDQRSS estimator is an unbiased of the population mean and more efficient than SRS, SRSS and SSRS for symmetric and asymmetric distributions. In addition, by SDQRSS we can increase the efficiency of mean estimator for specific value of the sample size.展开更多
A nonincreasing sequence ( of n nonnegative integers is said to be graphic if it is the degree sequence of a simple graph G of order n. The set of all graphic sequences of n terms with even sum 2m and trace f is a pos...A nonincreasing sequence ( of n nonnegative integers is said to be graphic if it is the degree sequence of a simple graph G of order n. The set of all graphic sequences of n terms with even sum 2m and trace f is a poset G_(n,m,f) under majorization relation. The paper characterizes the minimal elements in the poset G_(n,m,f) and determines the number of minimal elements in various posets of graphic sequences.展开更多
Let T be a tree with matching number μ(T). In this paper we obtain the following result: If T has no perfect matchings, thenμ(T) is a lower bound for the number of nonzero Laplacian eigenvalues of T which are smalle...Let T be a tree with matching number μ(T). In this paper we obtain the following result: If T has no perfect matchings, thenμ(T) is a lower bound for the number of nonzero Laplacian eigenvalues of T which are smaller than 2.展开更多
文摘针对汽车总装车间前的涂装车身缓冲区(Painted Body Storage)路由调度问题,结合线性缓冲区的结构特点,本文提出了一种基于两阶段匹配度的PBS路由调度策略。该策略以最大化匹配度为目标,第一阶段针对PBS车身的入库问题,构建了基于车身信息的匹配度模型,采用简单规则集法进行求解;第二阶段针对PBS车身的出库问题,构建了基于生产计划的匹配度模型,通过遗传算法进行求解。最后,通过实例分析验证了该算法的有效性。
文摘Let G be a simple graph with no isolated vertices. A set S of vertices of G is a total dominating set if every vertex of G is adjacent to some vertex in S . The total domination number of G , denoted by γ t (G) , is the minimum cardinality of a total dominating set of G . It is shown that if G is a graph of order n with minimum degree at least 3, then γ t (G)≤n/2 . Thus a conjecture of Favaron, Henning, Mynhart and Puech is settled in the affirmative.
文摘The procedure of stratified double quartile ranked set sampling （SDQRSS） method is introduced to estimate the population mean. The SDQRSS is compared with the simple random sampling （SRS）, stratified ranked set sampling （SRSS） and stratified simple random sampling （SSRS）. It is shown that SDQRSS estimator is an unbiased of the population mean and more efficient than SRS, SRSS and SSRS for symmetric and asymmetric distributions. In addition, by SDQRSS we can increase the efficiency of mean estimator for specific value of the sample size.
文摘A nonincreasing sequence ( of n nonnegative integers is said to be graphic if it is the degree sequence of a simple graph G of order n. The set of all graphic sequences of n terms with even sum 2m and trace f is a poset G_(n,m,f) under majorization relation. The paper characterizes the minimal elements in the poset G_(n,m,f) and determines the number of minimal elements in various posets of graphic sequences.
基金This research is supported by Anhui provincial Natural Science Foundation, Natural Science Foundation of Department of Education of Anhui Province of China (2004kj027)the Project of Research for Young Teachers of Universities of Anhui Province of China (2003jql01)and the Project of Anhui University for Talents Group Construction.
文摘Let T be a tree with matching number μ(T). In this paper we obtain the following result: If T has no perfect matchings, thenμ(T) is a lower bound for the number of nonzero Laplacian eigenvalues of T which are smaller than 2.
