现场总线PROFIBUS故障因素分析及故障诊断

本文主要针对现场总线PROFIBUS在现场应用中所产生故障的原因进行分析,并通过硬件设备信息及软件功能(FBl25)判断系统中的错误,诊断总线上站点的各种故障来进行探讨.     

The mailbox problem

We propose and solve a synchronization problem called the mailbox problem, motivated by a particular type of interaction between a processor and an external device or between two threads. In this problem, a postman delivers letters to the mailbox of a home owner and uses a flag to signal a non-empty mailbox. The owner must remove all letters delivered to the mailbox and should not walk to the mailbox if it is empty. We present algorithms and an impossibility result for this problem.     

The Superman problem

Given a polygonK contained in a polygonP, and a points lying outsideP, we present a (n logn) algorithm that finds the minimum number of edges, ofP that we want to retain in order to hidek froms. Furthermore, if the visibility polygon ofs givenK is unbounded, the algorithm is shown to run in linear time. This paper is dedicated to J. Siegel and J. Shuster.This work was supported by Friends of McGill Fellowship while T. Shemer was at McGill University.     

The interval-merging problem

A closed interval is an ordered pair of real numbers [x, y], with x ? y. The interval [x, y] represents the set {i ∈ R∣x ? i ? y}. Given a set of closed intervals I={[a₁,b₁],[a₂,b₂],…,[a_k,b_k]}, the Interval-Merging Problem is to find a minimum-cardinality set of intervals M(I)={[x₁,y₁],[x₂,y₂],…,[x_j,y_j]}, j ? k, such that the real numbers represented by equal those represented by . In this paper, we show the problem can be solved in O(d log d) sequential time, and in O(log d) parallel time using O(d) processors on an EREW PRAM, where d is the number of the endpoints of I. Moreover, if the input is given as a set of sorted endpoints, then the problem can be solved in O(d) sequential time, and in O(log d) parallel time using O(d/log d) processors on an EREW PRAM.     

IPv6的邻机发现协议

介绍了ＩＰｖ６中的一个重要协议,即邻机发现协议。阐述了其主要用途,涉及的数据结构、逻辑模型算法。最后将它与ＩＰｖ４中相应协议作了比较。并作了安全性方面的考虑。     

校园网网络拓扑发现技术研究

从现有的网络拓扑发现方法出发,结合本校校园网的实际情况,提出了一种分层对校园网进行拓扑发现的方法,并对该方法进行了详细论述。     

IPv6拓扑发现的研究

文章通过分析IPv6网络拓扑发现方面存在路由多址,交叉链路,隧道等问题,对这些问题进行了一些的分析。针对路由器多址问题,提出了自己的解决方法。文章基于Traceroute6网络管理工具实现对IPv6的拓扑发现。     

e-Science: The Added Value for Modern Discovery

e-Science, a new approach based on computer simulation, is increasingly being adopted as one of the most successful modern methods for experimental scientific discovery.     

The problem of hyperparamodulation

This article is the thirty-second of a series of articles discussing various open research problems in automated reasoning. The problem proposed for research asks one to find a variant of the inference rule hyperparamodulation that avoids generating many of the binary paramodulants ordinarily deduced.This work was supported by the Office of Scientific Computing, U.S. Department of Energy, under Contract W-31-109-Eng-38.     

The diffuse bomb problem

This paper considers the so-called diffuse bomb problem (the problem of collective penetration through a defense system). We perform simulation analysis by comparing six patterns with different “intelligence” levels in the behavior of moving objects (adaptivity, capacity for reflexion, forecasting, etc.). Finally, we demonstrate that endowing the objects with the ability of considering the parameters of a defense system and forecasting the behavior of other objects improves the efficiency of collective penetration through a defense system.     

The vendor location problem

The vendor location problem is the problem of locating a given number of vendors and determining the number of vehicles and the service zones necessary for each vendor to achieve at least a given profit. We consider two versions of the problem with different objectives: maximizing the total profit and maximizing the demand covered. The demand and profit generated by a demand point are functions of the distance to the vendor. We propose integer programming models for both versions of the vendor location problem. We then prove that both are strongly NP-hard and we derive several families of valid inequalities to strengthen our formulations. We report the outcomes of a computational study where we investigate the effect of valid inequalities in reducing the duality gaps and the solution times for the vendor location problem.     

The cocktail party problem

This review presents an overview of a challenging problem in auditory perception, the cocktail party phenomenon, the delineation of which goes back to a classic paper by Cherry in 1953. In this review, we address the following issues: (1) human auditory scene analysis, which is a general process carried out by the auditory system of a human listener; (2) insight into auditory perception, which is derived from Marr's vision theory; (3) computational auditory scene analysis, which focuses on specific approaches aimed at solving the machine cocktail party problem; (4) active audition, the proposal for which is motivated by analogy with active vision, and (5) discussion of brain theory and independent component analysis, on the one hand, and correlative neural firing, on the other.