基于有穷损害优先法求解组合拍卖竞胜标问题研究

迄今为止,组合拍卖竞胜标问题并不存在一个多项式时间复杂度的算法,其计算复杂性与拍卖效率之间的矛盾一直是影响组合拍卖广泛应用的主要障碍。它是一个NP难问题,也是组合拍卖机制设计中的难题之一。而有穷损害优先方法是纯粹递归论中的一个十分重要的现代方法,特别对NP难问题求解算法的设计,对研究依复杂度决定的偏序结构的构造是一个很基本的有用工具。因此,本文提出根据组合拍卖的内在特性,将各不同的拍卖商品按照拍卖机制的要求,并结合其自身的协同价值等因素,设定一个优先序,然后采用有穷损害优先法有效有序地解决。     

Rational ignorance and voting behavior

We model a two-alternative election in which voters may acquire information about which is the best alternative for all voters. Voters differ in their cost of acquiring information. We show that as the number of voters increases, the fraction of voters who acquire information declines to zero. However, if the support of the cost distribution is not bounded away from zero, there is an equilibrium with some information acquisition for arbitrarily large electorates. This equilibrium dominates in terms of welfare any equilibrium without information acquisition – even though generally there is too little information acquisition with respect to an optimal strategy profile.      

On eligibility by the de Borda voting rules

A criterion for eligibility of a candidate by the set of scoring rules (de Borda voting rules) is given. This criterion generalizes a necessary (but not sufficient) condition of eligibility in Moulin (Axioms of cooperative decision making, Cambridge University Press, Cambridge, 1988). The author thanks Profs. H. Moulin and A. V. Shapovalov for illuminating discussions.     

Multiple voting location problems

The facility voting location problems arise from the application of criteria derived from the voting processes concerning the location of facilities. The multiple location problems are those location problems in which the alternative solutions are sets of points. This paper extends previous results and notions on single voting location problems to the location of a set of facility points. The application of linear programming techniques to solve multiple facility voting location problems is analyzed. We propose an algorithm to solve Simpson multiple location problems from which the solution procedures for other problems are derived.     

一个具有自适应取阈功能的光电网络系统及其性能分析

提出了用光电混合网络来完成自适应取阈功能的硬件实现方法。该网络系统能根据输入状态的不同,通过网络单元间的相互竞争而达到对系统的阈值的自适应调整,使阈值总是等于最大输入值而完成“胜者全取”（WTA）。该网络系统主要由非晶硅半导体PIN光电探测阵列和“胜者全取”电子网络组成。又由于系统完全采用并行处理方式,因而具有响应速度快、灵敏度高、寻址能力强、结构简单和性能稳定等优点,能方便有效地应用于自适应取阈、相关峰检测、联想存储等光电混合系统,对一个36个单元的网络进行了实验测试并对其性能进行了分析。     

Condorcet — a man of the avant-garde

In 1785 Condorcet proposed a method to aggregate qualitative data, but until very recently this method was attributed to contemporary authors and its importance completely neglected.