配电网无功补偿算法研究综述

随着供需矛盾的加深及人们对供电质量要求的提高，配电网无功补偿成为目前供电部门一个重视的研究课题。针对配电网独特的特点，给出了配电网无功补偿的一般模型，并介绍了确定补偿电容位置、容量的传统算法及现行的各种人工智能方法，指出了各种算法的优缺点及改进之处，较全面地反映无功补偿算法的研究情况。     

战略物流管理的效益模型

战略物流管理是新兴的现代管理技术 ,其中核心问题是如何提高效益。效益模型的策划和找出影响它的主要因素是本文所要解决的问题     

Strategy-proof Location on a Network

We consider rules that choose a location on a graph (e.g. a road network) based on agents' single-peaked preferences. First, we characterize the class of strategy-proof, onto rules when the graph is a tree. Such a rule is based on a collection of generalized median voter rules (Moulin, 1980) satisfying a consistency condition. Second, we characterize such rules for graphs containing cycles. We show that while such a rule is not necessarily dictatorial, the existence of a cycle grants some agent an amount of decisive power, unlike the case of trees. Rules for this case can be described in terms of a subclass of such rules for trees. Journal of Economic Literature Classification Numbers: C72, D78.     

Descriptive statistics of large data sets by scatter plots, an exploratory approach

In the analysis of large tables of M variables on N observations one is interested in the relations between the variables and it is usual to inspect the M(M-1)/2 scatter plots of N points. Clearly, the scatter plot approach relies on visual inspection and is to be preferred in so far as applicable to detect simple relations, namely when M is small. Other approaches are needed for large values of M .
We consider that only the relatively few scatter plots that present a 'structure' are of interest for an exploratory analysis and, by 'structure', we mean a domain of specially high local density in the plot. Based on this concept, we propose a method constructed around two steps: the selection of the possibly interesting pairs of variables and the validation of the corresponding scatter plots. The selection of the pairs results from an algorithm based on a binary partitioning tree. The validation of the corresponding scatter plots enables the production of only those where a structure is found the recognition of a structure is derived from a statistic based on the length of the Minimum Spanning Tree constructed on the N points of the candidate scatter plot.
For illustration, we report on an industrial application where the method is routinely applied for exploratory purposes.     

林草结合 使林场成为新的畜牧基地

林业是国民经济的基础,这不是空泛的理论之争,而是如何进行经济建设及农业建设的实践之争。我国国土天然形成的大格局,决定了惟有实施林农牧共同发展的大农业战略,使山区、牧区、农区成三足鼎立之势,相互依持,共生共存,我国农业才有出路。这个大农业战略简称为"林草兴邦"。林草结合,也是国有林场建设的新思路。     

基于数据挖掘的电信客户信用分类模型研究

电信客户信用分析与预测,对于电信运营商在激烈竞争环境下,最大程度的在竞争活动中立于不败之地,具有重要意义。本文采用了SOM聚类算法和用传统经验对客户信用等级评分评级来确定信用等级类标号,再用决策树算法建立两个模型A和B。比较两个模型,选择性能较优者为最终模型并探讨了该模型的实际应用。     

基于余弦相似度(CS)和最小生成树(MST)的基金市场复杂网络研究

以中国基金市场中123家基金公司持有的投资组合为样本,综合运用余弦相似度(CS)和最小生成树(MST)方法,考量基金市场复杂网络。结果显示：各家基金公司持有股票组合的相似程度比持有债券组合的相似程度更高,表明他们持有的债券组合较之股票组合更加多元化,基金公司持有的股票相对集中于市值大、成长性高的公司。同时,全部资产投资组合、股票投资组合和债券投资组合等三类基金MST网络的节点度均服从幂律分布,表明大多数基金公司以少数强影响力基金公司为中心聚集起来,彼此之间具有较强的业务关联。此种网络结构特征可能导致市场风险向基金聚集团体集中,其抵御系统性风险的能力偏弱,也不利于满足投资者的理财多元化需求。     

军事供应链结构可靠性研究

军事供应链是与信息化战争相对应的后勤形态,为实现精确化后勤保障,研究军事供应链的可靠性非常必要。文章根据SCOR模型建立了军事供应链结构模型,将其划分为供应商网络和后勤配送网络,分别对基于Meta图模型的供应链和基于结构树模型供应链的结构可靠性进行定量描述,最后给出了计算军事供应链结构可靠性的公式。