p—a timesharing operating system for laboratory automation

An operating system supporting laboratory automation and interactive use of a computer has been designed and implemented for the multiprogrammed RC4000 computer. The emphasis in the design has been to give the user interactive access to as many system resources as possible, and to facilitate writing of process control programs in a high-level language, i.e. ALGOL. The operating system is used to run control and data collection programs for a variety of experiments in physical chemistry. Laboratory automation programs can be started and removed dynamically, and may even be restarted automatically after a system failure. The operating system is a 1500 line ALGOL program. The first version was designed, implemented and debugged in about 4 person-months. The operating system has been running day and night for approximately 5 years without errors despite heavy use.     

计算机信息系统安全技术的研究及其应用

随着信息时代的快速发展,计算机和互联网被越来越多的人使用并依赖着,计算机系统也逐渐成为了人们生活和工作的一大支柱。一旦这些计算机系统被破坏,所有以此来赖以生存的人或机构都会因此而崩溃。那么要保障人们工作和生活正常进行,计算机信息系统的安全保护措施就必不可少。     

Three Paradigms of Computer Science

We examine the philosophical disputes among computer scientists concerning methodological, ontological, and epistemological questions: Is computer science a branch of mathematics, an engineering discipline, or a natural science? Should knowledge about the behaviour of programs proceed deductively or empirically? Are computer programs on a par with mathematical objects, with mere data, or with mental processes? We conclude that distinct positions taken in regard to these questions emanate from distinct sets of received beliefs or paradigms within the discipline:

• The rationalist paradigm, which was common among theoretical computer scientists, defines computer science as a branch of mathematics, treats programs on a par with mathematical objects, and seeks certain, a priori knowledge about their ‘correctness’ by means of deductive reasoning.
• The technocratic paradigm, promulgated mainly by software engineers and has come to dominate much of the discipline, defines computer science as an engineering discipline, treats programs as mere data, and seeks probable, a posteriori knowledge about their reliability empirically using testing suites.
• The scientific paradigm, prevalent in the branches of artificial intelligence, defines computer science as a natural (empirical) science, takes programs to be entities on a par with mental processes, and seeks a priori and a posteriori knowledge about them by combining formal deduction and scientific experimentation.

We demonstrate evidence corroborating the tenets of the scientific paradigm, in particular the claim that program-processes are on a par with mental processes. We conclude with a discussion in the influence that the technocratic paradigm has been having over computer science.

     

The calculation of equilibrium concentrations. Estime: A computer program for comparing execution times on different machines

A computer program, ESTIME, has been written in several languages (FORTRAN, BASIC and Pascal), and in double and single precision versions. ESTIME uses the ES4EC algorithm for the computation of equilibrium concentrations, for a typical synthetic system of two metals, one ligand, the proton and 35 species. ESTIME is representative of computer programs that perform an analysis of equilibrium data in solution. In this study we report timing of calculations performed on different machines. Appendices 1 and 2 provide a listing of the FORTRAN version of ESTIME and one output example. Simple comparison parameters are proposed. We suggest that ESTIME will prove useful as a benchmark standard against which other programs may be compared. In this study we show that the relative performance of computer systems with ESTIME is comparable to the relative performance observed with other programs.     

代码重用攻击与防御机制综述

由于C与C++等计算机程序中广泛存在的漏洞,攻击者可以通过这些漏洞读取或篡改内存中的数据,改变计算机程序原有的执行状态达到破坏的目的。为此研究者进行了不懈地努力并采取了一些卓有成效的保护机制,例如数据不可执行与内存布局随机化,这些防御机制对于早期的代码注入攻击起到了极好的防御效果,然而计算机系统的安全性依然不容乐观。攻击者在无法通过向内存中注入自己的代码并执行的方式完成攻击后,开始利用内存中原有的代码,通过控制它们执行的顺序来达到自己的目的,这种攻击方式称为代码重用攻击,它具有极大的威胁性,能够绕过多种现行的安全措施,并成为攻击者的主流攻击方式。为此,研究界针对代码重用攻击的研究也逐渐增多。本文简述了代码重用攻击的起源,攻击实现的方式,系统化地总结了现有的防御机制并对这些防御机制进行了评价。对代码重用攻击的根本原因进行了简要的分析,并提出了一种新的防御机制设计思路。     

Different experiences,different effects: a longitudinal study of learning a computer program in a network environment

Students’ previous computer experience has been widely considered an important factor affecting subsequent computer performance. However, little research has been done to examine the contributions of different types of computer experience to computer performance at different time points. The present study compared the effects of four types of computer experience on 30 graduate students’ learning of a statistical program over one semester. Among the four types of computer experience, students’ earlier experience of using computer network systems was found to affect their initial performance of learning the statistics program, but the experience of using statistical programs, the experience of email programs, and the length of using computers did not. These findings suggest complex relationships between students’ computer experience and their computer performance and have implications for both learning and teaching computer programs and understanding the transfer of learning.     

Securing electronic data interchange

One of the growing areas of computer technology is electronic data interchange (EDI). Electronic data interchange is the electronic transfer of data from one agent to another. One of the most important problems with computer programs today is that they are not reliable. The reason for this is quite simple. Computer programs are built to solve particular problems and these problems can be quite large. By large we mean having lots of constraints, cases and rules as to what constitutes the problem. Real‐world problems are so complex that it is hard to be sure that when a program has been built it will never fail for an input that has not been taken into account. Hence, reliability of computer programs for EDI has serious implications because if a program fails to work then this can lead to problems with security. If the field of computer science concentrates on better techniques for increasing computer reliability then we will be able to build more reliable and secure programs for EDI.     

微处理机串行口终端模拟器设计

利用单片机、液晶显示器等组成一个微处理器串行口终端模拟器系统,模拟单片机之间或单片机与计算机之间通过串行口传输数据的通信方法。通过设计硬件接线电路设计和编写相关的程序,该设计最终实现了上述目的。     

A set of software to compile admission summaries for surgical patients using the BBC microcomputer

A set of software has been devised to enable medically qualified personnel without special computer skills to assemble and print admission summaries for their patients. The program has been written to run on a 32k BBC microcomputer with disc filing system and a printer. There are three programs in this set of software. These are a list of useful words and phrases, a data entry program with full editing facilities and a printing section with some word processing functions. All programs are prompted from menus and call each other where required.     

Re-examining the proprietary software protection issue in the U.S.A. for the 1980s

Recent developments in statutory and case law in the USA now make it possible to protect by copyright, proprietary computer programs from unauthorized copying provided that the copyright-holding party attempts to display the copyright notice publicly. Considerable progress has been made toward patentable computer software, but the issue of whether a computer program itself may be patented still remains unresolved. The Patent and Trademark Office (PTO) and the Court of Customs and Appeals (CCPA) have agreed that the application of a computer program, containing a mathematical algorithm, in a process may constitute patentible subject matter. The cases pertaining to copyrightable and patentable software together with an explanation of the wording of the new Section 117 of the 1976 Copyright Act are shown in the Appendixes to the article. The paper presents the issues pertaining to copyright and patent protection of computer software and some relevant cases for each issue. It concludes with a discussion of unresolved questions in protecting proprietary software.     

Automatic Setting of Article Format Through Neural Networks

The automatic format-setting of journal articles for reducing the workload of computer users involves two processes: automatic acquisition of article format and automatic recall of article formal. Several neural networks have been explored to implement the two processes. The advantages and disadvantages of these neural networks are evaluated in comparison with capabilities of conventional computer programs. A heteroassociative back-propagation network has been developed for the automatic acquisition process. This network excels over computer programs because of its abilities in learning and generalizing implicit knowledge from examples. A bidirectional associative memory network, a Boltzman network, and an autoassociative back-propagation network have been investigated for the automatic recall process. None of them excel over computer programs in terms of recall accuracy.     

浅谈市级气象影视制作系统的日常维护

近年来,气象影视事业蓬勃发展,天气预报栏目已成为人们每天必看的电视节目,要想呈现一部高质量的气象影视节目,与影视制作相关的计算机设备显得格外重要。本文着重介绍了市级气象影视系统硬件日常出现的故障和维护,软件日常维护和备份及安全防护。     

Experiences with Open Source Software Engineering Tools

For software engineering (SE) and computer science (CS) programs to deliver on their promises, they must go beyond teaching students about principles, processes, models, and strategies and offer them realistic, practical experience as well. Although industry has been pressing to increase the emphasis on practical aspects, many CS programs continue to give students relatively simple problems focused on selected computing and software concepts and theories. Open source software offers CS and SE educators an opportunity to give their students practical, hands-on software engineering experience     

Hierarchical data management for structural analysis

The use of formal data bases management systems is becoming increasingly necessary in computer programs for structural engineering. This paper briefly reviews data base requirements and the organization of integrated computer program networks and identifies a need for hierarchical data base management in computer programs for structural analysis. The nature of the data hierarchy is illustrated with reference to a building that has been analyzed by using substructure techniques. The organization and features of the hiearchical data base manager STRATA are then described. STRATA has been developed specifically for use in structural analysis.     

An intelligent consultant system for chess

This paper deals with the problem of teaching chess. We describe the ideal characteristics for a learning environment for chess and discuss a partial implementation of such an environment; ICONCHESS. An Interactive Consultant for Chess Middlegames. Most research on computer chess has focused on creating highly competitive chess playing programs, regardless of the means used to achieve this goal. Because of the success obtained by programs based on search algorithms, little effort has been put on chess playing programs that play using high level strategies, which are necessary in human chess players. This lack of strategic foundations makes most chess playing programs inadequate as chess tutors too. This paper presents a new approach for computer chess in general and specifically for a learning environment for chess. This approach combines the techniques of fuzzy logic and case-based reasoning in order to produce high level advice for chess positions. We also present the results of the empirical experiments used to test ICONCHESS and suggest some ways in which the approach can be applied to other domains.     

Introducing the new industrial engineer

During the last couple of decades, we industrial engineers have typically learned FORTRAN, plus a simulation language or two, gathered together a few optimization programs, and have proclaimed ourselves computer users and, in some cases, even computer experts. Ours has been a somewhat passive expertise, however. That is, with the possible exception of contributions to simulation language development, industrial engineers have not been in the forefront of the wave of computer developments. This has not been entirely our fault. Computers were expensive and hard to justify; utilization was often inconvenient; processing and turnaround was slow; input and output media were few and often unreliable; program development via cards was lengthy, painstaking and cumbersome; and implementation was usually suspect and unpopular.But a funny thing happened in the last few years. Computers, which are so necessary for so many IE-type functions, suddenly became…(a) inexpensive, (b) acceptable, (c) abundant, (d) popular, (e) prominent and most important of all (f) necessary. Industry's key catchword of “profitability” was replaced by “productivity” and suddenly the IE and his stock-in-trade were once more thrust into the forefront. But the tools of days past are no longer enough. The computer will be our constant companion from now on, not as it has been in the past, but as we are innovative enough to make it in the future.This paper is about the computer, computer languages, computer innovations and computer uses, but mostly it is about the new industrial engineer and the environment in which he must exist. It is about the challenges, the opportunities and the direction of the trully modern IE and the role he must play.     

计算机网络安全常见攻击与防范

目前互联网在人们的生产、学习和生活中以及在国家的政治、经济、文化生活中的作用,已显得十分突出,全社会对互联网的依赖程度也越来越高。同时也出现了一些不可忽视的问题,有人利用互联网故意制作、传播计算机病毒等破坏性程序,攻击计算机系统及通信网络,危害网络运行安全。本文根据以下参考文献,结合工作中的实际经验,针对目前计算机网络安全方面的常用攻击方法以及防护措施提出一些建议以做参考。     

The structure of computer anxiety: a six-factor model

A six-factor model of computer anxiety was tested in two samples of university students. The dimensions involved were: computer literacy, self-efficacy, physical arousal caused by computers, affective feelings about them, beliefs about the beneficial effects of computers, and beliefs about their dehumanizing aspects. Confirmatory factor analyses showed that, compared to a number of alternative models proposed in the literature, the data fitted this six-factor model relatively well. In addition, it was demonstrated that computer literacy has a strong directional influence on both physical arousal and affects. Beliefs about computers, in turn, were shown to be dependent on affects and physical arousal. Self-efficacy mainly contributed to increased computer literacy. These findings suggest that training programs that enhance self-efficacy and computer literacy may in principle reduce computer anxiety.     

计算机网络信息安全及防护策略研究

随着因特网技术和计算机技术的快速发展,计算机网络信息安全及其防护已经越来越受到民众的重视和关注。文章主要针对计算机网络信息安全进行了深入的分析,并且针对计算机网络信息安全存在的问题提出了一些防护策略。