A radio network for monitoring and diagnosing computer systems

By offering improved reliability and lower implementation cost, an interconnect technology based on radio communication provides an attractive alternative for implementing system functions requiring out-of-band signaling.     

Simulation of buried power transmission systems: Some computer graphics options

This paper discusses some computer graphics options useful for both computation and display of three-dimensional motions within buried high-voltage power transmission lines as they undergo temperature changes (load cycling).     

Special issue on the use of computer algebra systems for computer aided control system design

The importance of the continuing and growing need in the systems and control community for reliable algorithms and robust numerical software for increasingly challenging applications is well known and has already been reported elsewhere (IEEE Control Systems Magazine, Vol. 24, Issue 1). However, we have all had the experience of working on a mathematical project where an increased number of symbolic manipulations was needed. In a simple case, the required computation might have been to compute the Laplace transform or the inverse Laplace transform of a function, or to find the transfer function matrix for a given system topology where parameters are included. In a more demanding situation the required computation might have been to find the parametric family of solutions of a polynomial matrix Diophantine equation resulting from a variety of control problems such as those associated with stabilization, decoupling, model matching, tracking and regulation, or to compute the Smith McMillan form of a rational transfer function matrix in order to obtain a better insight into a number of structural properties of a system. The desire to use a computer to perform long and tedious mathematical computations such as the above led to the establishment of a new area of research whose main objective is the development: (a) of systems (software and hardware) for symbolic mathematical computations, and (b) of efficient symbolic algorithms for the solution of mathematically formulated problems. This new subject area is referred to by a variety of terms such as symbolic computations, computer algebra, algebraic algorithms to name a few. During the last four decades this subject area has accomplished important steps and it is still continuing its evolution process.     

Some observations on grid convergence

It is claimed that current practices in grid convergence studies, particularly in the field of external aerodynamics, are flawed. The necessary conditions to properly establish grid convergence are presented. A theoretical model and a numerical example are used to demonstrate these ideas. It is shown that anomalously low or high observed convergence rates can be exhibited by otherwise well-behaved algorithms because of improper use of grid refinement ratios in different directions.     

财经院校计算机专业Java教学探讨

针对财经院校计算机专业Java教学中存在的教学内容定位不准确、安排不合理、理论与实践相脱离、教师缺乏实际开发经验等问题,提出并探讨了准确定位教学目标、合理安排教学内容、优化教学手段,理论与实践相结合、加强对教师的培养等应对措施.     

基于实时监控的计算机安全解决方法

随着科技的发展,计算机技术也在我国迅速发展起来,随着计算机技术的不断普及和发展,计算机产品的系统安全也成为人们所关注的问题.如何实现计算机产品和技术的系统的安全性成为人们研究的重要内容,本文根据BIOS原理以及USBkey技术特点介绍了一种基于实时监控的计算机安全解决方法,以期对计算机的系统安全提供参考性意见.     

Using Bayesian networks for monitoring computer users

The structure and methods of a knowledgebase are discussed. This knowledgebase is considered to be a component part of personal expert systems designed for monitoring computer users and computer environments with a view to detecting a harmful effect of computers on the state of health of computer users and making recommendations concerning the neutralization of this effect. Such expert systems are based on Bayesian networks that have a simple topology and represent random relations between harmful conditions of a computer environment and the state of help of users.Translated from Kibernetika i Sistemnyi Analiz, No. 6, pp. 3–15, November–December 2004.This revised version was published online in April 2005 with a corrected cover date.     

A framework for evaluating economics of knowledge management systems

Organizations are implementing knowledge management (KM) systems with the assumption that the result will be an increase in organizational effectiveness, efficiency, and competitiveness. Implementing KM systems, however, may be a problem to organizations: too much or too little effort might lead to unwanted outcomes. This paper shows how the introduction of KM systems, which lead to knowledge-sharing, has a negative as well as a positive effect. Important variables from economic perspectives are identified and presented as an integrated framework to illustrate their interrelationships. This paper also explains the implications of an integrated framework for knowledge flow in organizations.     

A framework for evaluating economics of knowledge management systems

Organizations are implementing knowledge management (KM) systems with the assumption that the result will be an increase in organizational effectiveness, efficiency, and competitiveness. Implementing KM systems, however, may be a problem to organizations: too much or too little effort might lead to unwanted outcomes. This paper shows how the introduction of KM systems, which lead to knowledge-sharing, has a negative as well as a positive effect. Important variables from economic perspectives are identified and presented as an integrated framework to illustrate their interrelationships. This paper also explains the implications of an integrated framework for knowledge flow in organizations.     

Development methods for trusted computer systems

Conclusion Well-designed computer systems can be safer than hardwired alternatives, and computer systems can control processes which are too complex for hardwired solutions, or where the hardwired solution is uneconomic.     

Performability analysis for degradable computer systems

Degradable performance of fault-tolerant computer systems has given rise to considerable interest in mathematical models for combined evaluation of performance and reliability. Most of these models are based upon Markov processes. Several methods have been proposed for the computation of the probability distribution of performability upon an interval of time [0, t]. In this paper, we present a new algorithm based on the uniformization technique to compute this distribution for block degradable models. The main advantage of this method is its low polynomial computational complexity and its numerical stability, since it only deals with a nonincreasing sequence of positive numbers bounded by 1. This important property allows us to determine new truncation steps which improve the execution time of the algorithm. We apply this method to a degradable computer system.     

Satellite systems for atmospheric ozone observations

A review of the satellite-borne instrumentation used for the total ozone and ozone vertical profile watch is presented. The principle of the observational method for the monitoring of the atmospheric ozone content is used to group the basic satellite systems. Along these lines the direct-absorption, scattering, and emission-measuring instruments are presented, besides providing a short discussion on the spatio-temporal variability of the ozone content mainly derived from a few outstanding field campaigns.     

Diffusion approximation for multiprogrammed computer systems

This paper presents results of diffusion approximations which may be used in the analysis of multiprogrammed computer systems. First of all we give a mathematical proof for the best CPU utilization under different priority rules in the case of one CPU and more DTU-s. With the help of the Brownian motion approximation we get an explicit result for a model considered by Gaver and Shedler in priority queues, without using the Wald identity. Some examples are given when the diffusion approximation is more complicated than the Brownian motion one.     

对计算机专业英语教学的几点思考

计算机专业英语是计算机专业教学体系中的一门重要课程,对学生掌握计算机领域的专业知识,了解国际前沿学术动态有重要作用。从计算机专业英语的学科特点和教学现状入手,分析当前计算机专业英语教学中存在的问题,结合自身教学实践,探索教学模式并提出能够提高计算机专业英语教学效果的方法。     

Methodologies for the cost-benefit analysis of computer graphics systems

This paper assesses the state of the art in cost-benefit analyses of computer graphics systems and suggests an approach for developing improved methodology. Cost-benefit analyses are distinguished from analyses of system performance in that the latter is directed at optimizing system performance at a given level of investment, while the former is directed at justifying the investment itself.Computer graphic system design alternatives are first outlined. Then methods of analyzing the performance and costs of computer systems in general and graphic systems in particular are discussed. With this information it is shown how cost-effectiveness analyses may be performed. The next crucial step is to conduct benefit analysis, an ill-defined art. The results of benefit analysis must be combined with cost-effectiveness analysis in order to perform the desired cost-benefit analysis.An experimental methodology is suggested for better performing benefit analyses of computer graphics systems. A more rigorous formulation of the cost-benefit procedure is then outlined. No attempt is made in this report to actually perform such an analysis.     

Mathematical methods for the modular design of computer systems

An approach to modular design is proposed, involving the estimation of the information transfer between the modules of acomplex system.In apreviouspaper[l], a general decomposition criterion was derived, employing the entropy function as a measure of the amount of information contained within a system or subsystems. This paper concerns the formulation of an algorithm for the optimisation of the criterion which decomposes hierarchically a system into its most independent subsystems or modules. A simple illustrative example is given and further, the design methodology is applied to detect the modular structure of a computer teaching system.