Cycle factors in strongly connected local tournaments

A digraph without loops, multiple arcs and directed cycles of length two is called a local tournament if the set of in-neighbors as well as the set of out-neighbors of every vertex induces a tournament. A digraph is 2-connected if the removal of an arbitrary vertex results in a strongly connected digraph.In 2004 and 2005, Li and Shu investigated the structure of strongly connected, but not 2-connected tournaments. Using their structural results they were able to give sufficient conditions for a strongly connected tournament T to have complementary cycles or a k-cycle factor, i.e. a set of k vertex disjoint cycles that span the vertex set of T.Inspired by the articles of Li and Shu we develop in this paper the structure necessary for a strongly connected local tournament to be not cycle complementary. Using this structure, we are able to generalize and transfer various results of Li and Shu to the class of local tournaments.     

Development and Validation of a Computer‐Administered Number Sense Scale for Fifth‐Grade Children in Taiwan

To investigate the structure of number sense and then to assess its uses in fifth‐grade children's number sense development, a computerized number sense scale was developed and evaluated. The findings of the study indicate that the newly developed scale, with four dominant factors identified and reconfirmed, is internally consistent and substantially valid. It can be reliably used as a screening measure for a quick check of students' number sense development via online self‐assessment. Compared with our previous study, both qualitative and quantitative changes were detected in students' number sense development at different grades. The qualitative change in number sense development is manifested in different numbers of factor components produced at different grades. The quantitative change is manifested in different amounts of factor variance explained at different grades. Furthermore, among the four aspects of number sense, Taiwanese students perform best on recognizing the relative number size yet relatively worse on judging the reasonableness of computational results.     

制造商与两个具有竞争性的零售商的两阶段博弈模型

针对一个制造商和两个具有竞争性的零售商组成的供应链两阶段博弈模型.首先考虑下游零售商之间的Stackelberg博弈,然后又以整体最优讨论制造商为主导的Stackelberg博弈的两阶段博弈模型.数字实验结果表明:该策略不仅能提高制造商的利润,而且能改善销售商的利润,特别是对于供应链成员之间具有较高的竞争强度.     

一维六方准晶中带三条不对称裂纹的圆形孔口问题的解析解

利用复变函数方法,通过构造保角映射,研究了一维六方准晶中带不对称三裂纹的圆形孔口的反平面剪切问题,给出了Ⅲ型裂纹问题的应力强度因子,在极限情形下,不仅可以还原为已有的结果,而且求得一维六方准晶中L裂纹问题在裂纹尖端的应力强度因子.     

带有因子约束锥的DEA模型

传统DEA模型将输入输出指标对评价结果的影响等同看待,与实际情况不符.学者们不断尝试运用各种方法对DEA模型中指标的权重进行约束,以体现不同指标重要性的不同.但是,目前的相关研究大多采用主观评价方法,这样会破坏DEA的客观性,而采用因子分析确定的权重是客观的,所以在DEA模型中建立因子约束锥,对权重进行约束,可以在保持DEA客观性不变的基础上体现不同指标重要性的不同.     

径流中长期预报模糊识别优化模型及应用

对水文中长期预报模糊识别方法进一步研究,基于模糊环境下的目标函数,提出了具有主观监督因子和稳定系数的模糊识别预报模型.根据已知样本的最优模糊划分建立预报模型,利用已知样本的指标和样本的最优模糊划分计算预报模型的参数,给定模型的稳定系数,再通过调整主观监督因子对预报模型参数进行优化.径流中长期预报实例的模型检验平均相对误差为7.84%.     

一个关于图是分数(k,n)-临界的邻域并条件

设G是一个图,以及k是满足1≤k的整数.一个图G在删除任意n个顶点后的子图均含有分数k-因子,则称G是一个分数(k,n)-临界图.给出了图是一个分数(k,n)-临界图的一个邻域并条件,并且该条件是最佳的.     

110警车配置及确定巡逻方案的问题

主要讨论社会安全系统中警车的优化配置及巡逻方案的合理安排问题.首先对道路和重点区域进行合理离散化,再根据离散化后得到的新地图计算出各个离散道路点的邻域,然后对静态过程使用模拟退火算法得到静态优化值,最后根据不同的目标和需求,通过对动态过程进行仿真,从而得到最后满足要求的动态优化值,并按照问题要求给出所需的评价值和合理的警车巡逻方案.该模型原理清晰易懂,采用启发式算法,计算简单,通用性强,优化性能显著,稳定性好.     

基于省际面板数据的全要素生产率的计算:1995-2006

本文采集并处理了1995年到2006年间全国30余个各省、直辖市和自治区的产出、资本投入和劳动力投入的数据,经过单位根检验、协整分析和模型选择,利用面板回归模型,计算了各地区的TFP及其在不同时期的增长率。研究表明,1995年-2006年间东部省份的TFP水平要高于中西部地区,但TFP水平较高的省份的TFP增长率速度并不一定高,尤其是部分东部省份的TFP的增长率出现了下降,而部分西部地区的TFP的平均增长率发展势头较好。     

用多元统计方法分析浙江省各地区的经济结构

本文首先利用因子分析方法研究浙江省11个地级市之间的相关性,利用因子得分得到浙江省11个地级市的综合排名。然后又把因子得分作为新变量,用聚类分析法对各地级市进行分类,把浙江省11个地级市分为4类。在统计分析的基础上对浙江省未来发展提出一些有益的建议,供有关部门参考。