Economies of scale in the US computer industry: An empirical investigation using data envelopment analysis

Up to recently, economists have had no good tools to measure the returns to scale of individual corporations in an industry. Data envelopment analysis (DEA) is a linear programming technique for determining the efficiency frontier (the envelope) to the inputs and outputs of a collection of individual corporations or other productive units. While DEA offers an avenue for calculating the returns to scale of individual corporations, the approach has been riddled by mathematical complications arising from the possibility of alternate optima. The present paper develops theory for calculating the entire range of these alternate optima. Furthermore, in a quite ambitions empirical application, DEA is employed to determine the time path of returns to scale of all publicly held U.S. computer companies over the time period 1980–1991. For the great majority of companies, a unique time path is obtained; only in less than 4 percent of the linear programming calculations is an entire range of alternate optima obtained. The results indicate that the computer industry was polarized into two camps: large aging corporations with decreasing returns to scale, and swarms of small upstart companies with advanced technology exhibiting increasing returns to scale.     

高素质师资队伍是计算机基础教学改革的保障

结合内蒙古财经学院计算机基础教学改革,分析了原计算机基础教学中存在的主要问题,介绍了以培养学生学习和应用计算机的能力、使学生更好地利用计算机去解决专业领域中的问题为目的的计算机基础教学体系设计。着重探讨了为保障这一教学体系实现,教师应进行的一些转变和要开展的一系列工作,从而给出了计算机基础教学中师资队伍应具备的能力与素质。     

MCS—51单片机间的远程数据通信

本文介绍了利用MCS—51单片机现有软件和硬件资源实现远程数据通信的一种简单实用的方法。由这一方法构成的系统具有较低的成本和较高的可靠性。文中最后给出了接收和发送实验程序清单。     

计算机串行通信综述

本文着重向读者介绍目前流行的几种计算机串行通信规程，它们是ＥＩＡ－ＲＳ－２３２Ｃ、ＥＩＡ－ＲＳ－４２２Ａ、ＥＩＡ－ＲＳ－４２３Ａ、ＥＩＡ－ＲＳ－４４９、ＥＩＡ－ＲＳ－４８５、ＡＲ－ＩＮＣ－４２９等。     

Field study with a computer-based office system

The authors describe a field study of computer-based aids in the office. The study was based on the assumption that a computer system should prove itself under realistic everyday conditions. The results show that advanced technology can be effectively applied at the executive level, where unstructured and variable activities are to be supported. Thus the authors do not confine themselves to technical issues - personal and organizational factors are also taken into account. The main aspects examined are system utilization, training and introduction strategy.     

TDRSS地面站Ka频段收发信道

网上零售的兴起离不开买卖双方的推动和零售业自身发展规律的影响。网上零售能否成功取决于因特网在信息渠道、实体分配渠道和所有权转移渠道方面功能的发挥。由于因特网自身的特点,网上零售的产品应有所选择,并制定相应的策略才能取得满意的绩效。     

浅谈对计算机操作系统的认识

计算机操作系统,是电子计算机系统中负责支撑应用程序运行环境以及用户操作环境的系统软件,同时也是计算机系统的核心与基石。本文对计算机操作系统的使命、功能和学习窍门等方面进行了简单的分析和阐述。     

计算机人工智能技术在工程地质中的应用

工程地质问题由于各种客观和人为的因素，存在许多不确定性或在理论上未能解决的问题，常常需要依靠专家丰富的经验进行智能化处理，这很适合用人工智能的思想和方法来解决。本文简介人工智能技术及其在工程地质领域的应用，并对其应用前景进行了展望。     

计算机会计信息系统的人-机接口设计

本文论述了电子计算机会计信息系统人一机接口的设计原则与设计要点。