生产系统的计算机仿真研究

生产系统在设计与运行过程中面临着诸多的问题需要解决，计算机仿真技术作为一种有效验证生产系统设计合理性和辅助生产管理决策的手段，近年来在我国得到了越来越广泛的关注。该文系统总结了计算机仿真技术对生产系统的重要作用，利用Ithink5.0软件建立了简单生产过程的计算机仿真模型并进行了分析。     

User Interfaces for Complex Engineering Software: Application of Virtual Reality

IT systems for engineers are becoming more numerous and complex and will further proliferate in the future. It is infeasible to expect users to be trained to work with a plethora of systems, especially as many of them will only see occasional use. Therefore, in the near future, systems will need user interfaces that allow intuitive access and usage. This paper examines a new style of user interface based on virtual reality.     

Efficient Spreadsheet Algorithm for First-Order Reliability Method

A new spreadsheet-cell-object-oriented algorithm for the first-order reliability method is proposed and illustrated for cases with correlated nonnormals and explicit and implicit performance functions. The new approach differs from the writers earlier algorithm by obviating the need for computations of equivalent normal means and equivalent normal standard deviations. It obtains the solution faster and is more efficient, robust, and succinct. Other advantages include ease of initialization prior to constrained optimization, ease of randomization of initial values for checking robustness, and fewer required optimization constraints during spreadsheet-automated search for the design point. Two cases with implicit performance functions, namely an asymmetrically loaded beam on Winkler medium and a strut with complex supports are analyzed using the new approach and discussed. Comparisons are also made between the proposed approach and that based on Rosenblatt transformation.     

电缆气压保气率计算机统计系统

介绍了电缆气压保气率计算机统计系统开发的目的和意义，系统程序的流程和结构，以及系统程序的编制和应用。     

异质谷间转移电子器件的计算机模拟

使用弛豫时间近似求出了描述两能谷间电子交换的方程。在此基础上建立了双能谷电子的连续性方程和油松方程。对具体的ＧａＡｓ／ＡｌｘＧａ１－ｘＡｓ异质谷间转移电子器件结构求解了这些方程组，得到了直流工作时器件内的电场分布、双能谷中载流子的布居以及两个能谷的电流分布。这些结果正好和常规Ｇｕｎｎ器件相反，说明了两种器件的不同工作机理。最后通过对低Ａｌ组份势垒结构的计算说明了Ｘ谷电子注入对器件工作的重要作用。     

行波管质量与可靠性信息管理系统的设计

本文从应用角度简要介绍了《行波管质量与可靠性信息管理系统》的研制背景，数据库的数据来源，数据结构，系统构成及功能特点。     

光学系统中离轴性公差的计算机设计

运用不共轴光学系统的光路计算和象质评价理论，通过共轴光学系统中光学表面，光学元件，部件的小位移和微倾斜，对切比雪夫综合象质函数计算相应的有关限差分，以掌握各种离轴性误差对象质的危害程度，再按多元函数的极值理论和适应度性优化技术自动妥共轴光学系统中各种轴性公差，并进行反馈和非线性处理；达到公差的最优化分配。     

Motion Perception Using Analog VLSI

Motion perception is arguably a fundamental mechanism used by natural species to accomplish a number of tasks, such as navigating freely in an unknown environment. Traditional motion perception methods tend to be computationally intensive, requiring powerful computers and large memories. However, by copying biological mechanisms, such as elementary motion discrimination at the early stages of the visual processing paths, it should be possible to build small and efficient motion perception systems. This paper describes the manner in which a simple motion perception model based on the insect visual system has been implemented using mixed analog/digital VLSI. The device has been fabricated in a 2 micron double metal, double polysilicon process, and comprises 61 photo-detectors, and associated analog and digital circuitry. While not entirely successful in that component mismatches hamper the detection of dark-to-bright changes in contrast, the results clearly show the feasibility of using such a device in autonomous control systems.     

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。     

CIMS环境中的数据模式转换

本文在分析CIMS环境中数据模式冲关类型的基础上，提出一种互连数据库系统模式结构，论述了在异构数据库集成中解决模式冲突的基本方法．在这种方法体系中，不需要建立整个企业的全局数据模式，各局部DBA以简单的方式定义应用所需的模式变换，系统根据这种定义自动完成各种转换，使用户看到的模式和数据结果与应用要求的一致．