改进后的PERT方法在进度风险分析中的应用

风险分析是进度控制中的重要内容。针对经典PERT网络的假设和计算过程,分析出它存在的三方面缺陷。并提出解决问题的三种具体措施,从概率论与数理统计的角度,对关键线路和关键工作进行了重新定义和确定的方法。     

旅行社的旅游线路优化设置问题探讨

尽管在旅游线路的设计过程中需要解决的问题很多,但从优化的角度而言,如何设计出一条能实现出发地与目的地间的最短路径目标,便是其中的最为关键性的一个问题。由于不同的交通方式的不同组合能对应着不同的路程、时间与成本问题,因而,如何通过有效的选择来形成最佳的旅游线路也就有了相当的必要性。此外,在旅游线路设计与安排过程中,旅行社除了要合理安排和规划旅游线路的长度以力求不走回头路、不走冤枉路和形成有效的闭合回路外,还需充分考虑到其中的线路在时间安排上的合理问题;否则,再好的线路安排也会失去其内在的价值与影响力。     

Learning across the life cycle: Experimentation and performance among the hollywood studio heads

Guided by notions from the literature on organizational learning, this paper investigates how product line experimentation and organizational performance change across the careers of top managers. Its subjects are the studio heads who ran all the major Hollywood film studios from 1936 to 1965. The study found first, that product line experimentation declines over the course of executive tenures; second, that there is an inverse U‐shaped relationship between top executive tenure and an organization's financial performance; and third, that product line experimentation is more likely to benefit financial performance late in top executives' tenures. These findings are consistent with a three‐stage ‘executive life cycle’. During the early years of their tenures, top managers experiment intensively with their product lines to learn about their business; later on their accumulated knowledge allows them to reduce experimentation and increase performance; finally, in their last years, executives reduce experimentation still further, and performance declines. Copyright © 2001 John Wiley & Sons, Ltd.     

经济生产量模型对库存的控制

在分析需求变化的基础上修改和完善了经济批量模型,进一步研究了单项物品和多项物品的最小经济生产批量以及年最小总成本,改进了经济生产量模型。     

论邓小平创新精神的来源

邓小平能够敢想敢做,在于他鲜明的创新精神。邓小平的创新精神来源于他对党和人民事业的无限忠 诚;实事求是的思想方法和求真务实的工作态度;非凡的勇气和胆略;密切联系群众的优良作风;以及高瞻远瞩的战 略眼光和敏锐的时代洞察力。     

一种镀锌板生产线电气传动控制系统

介绍了镀锌板生产线的工艺流程及其对电气传动的要求，采用PLC对镀锌板生产线的张力和带速进行协调控制，对电气传动控制系统的活套带重补偿和控制算法作了论述。本系统在实际使用中可靠性高，经济效益好，是一种适用的镀锌板生产线电气传动控制系统。     

论城市交通网对旅游交通的影响--以重庆为例

旅游交通是旅游业发展的充要条件，交通条件的优劣在很大程度上决定了旅游经济发展的快慢。笔通过分析重庆市旅游交通条件的现状，认为必须依托城市交通网进行旅游线路布局，并提出了改善重庆旅游交通条件的对策措施。     

How many voters are needed for paradoxes?

Summary. This paper presents a general procedure for finding profiles with the minimum number of voters required for many important paradoxes. Borda's and Condorcet's classic examples are revisited as well as generalizations. Using Saari's procedure line, we obtain an upper bound for the minimum number of voters needed for a profile for which the Condorcet winner is not strictly top ranked for all weighted positional procedures. Also we give a simple upper bound on the minimum number of voters needed for a set of prescribed voting outcomes. In contrast to situations wherein small numbers of voters are needed, we consider paradoxes requiring arbitrarily large numbers of voters as well as large numbers of alternatives. Finally we indicate connections with statistical rank based tests. Received: April 18, 2001; revised version: May 25, 2001     

贫困线测定方法研究

马丁法是符合我国实际的贫困线测定方法 ,依据马丁法可科学测定食物贫困线、非食物贫困线、低贫困线和高贫困线。     

API Spec 15HP-1995《高压玻璃纤维管线管规范》的分析与介绍

本文介绍了高压玻璃纤维管线管规范的制定技术背景和主要特点,分析了前后两版的修订内容及原因.