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41.
Energy minimization and design for testability 总被引:6,自引:0,他引:6
Srimat T. Chakradhar Vishwani D. Agrawal Michael L. Bushnell 《Journal of Electronic Testing》1994,5(1):57-66
The problem of fault detection in general combinational circuits is NP-complete. The only previous result on identifying easily testable circuits is due to Fujiwara who gave a polynomial time algorithm for detecting any single stuck fault inK-bounded circuits. Such circuits may only contain logic blocks with no more thanK input lines and the blocks are so connected that there is no reconvergent fanout among them. We introduce a new class of combinational circuits called the (k, K)-circuits and present a polynomial time algorithm to detect any single or multiple stuck fault in such circuits. We represent the circuit as an undirected graphG with a vertex for each gate and an edge between a pair of vertices whenever the corresponding gates have a connection. For a (k, K)-circuit,G is a subgraph of ak-tree, which, by definition, cannot have a clique of size greater thank+1. Basically, this is a restriction on gate interconnections rather than on the function of gates comprising the circuit. The (k, K)-circuits are a generalization of Fujiwara'sK-bounded circuits. Using the bidirectional neural network model of the circuit and the energy function minimization formulation of the fault detection problem, we present a test generation algorithm for single and multiple faults in (k, K)-circuits. This polynomial time aggorithm minimizes the energy function by recursively eliminating the variables. 相似文献
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43.
一种适合协同工作系统的安全认证方案 总被引:2,自引:0,他引:2
针对网络化协同工作系统的安全认证需求,综合应用Kerberos协议、X.509证书和口令认证技术,借鉴PKI的思想,设计了一种适合网络化协同工作系统的灵活而易于扩展的安全认证方案。这个方案能够保证证书的安全分发,满足网络化协同工作系统对分散、动态的用户安全身份认证的要求。 相似文献
44.
Optimal solutions of several variants of the probabilistic reasoning problem were found by a new technique that integrates
integer programming and probabilistic deduction graphs (PDG). PDGs are extended from deduction graphs of the and-type via
normal deduction graphs. The foregoing variants to be solved can involve multiple hypotheses and multiple evidences where
the former is given and the latter is unknown and being found or vice versa. The relationship among these hypotheses and evidences
with possible intermediaries is represented by a causal graph. The proposed method can handle a large causal graph of any
type and find an optimal solution by invoking a linear integer programming package. In addition, formulating the reasoning
problem to fit integer programming takes a polynomial time.
H.-L. Li was visiting the Department of Computer Sciences, University of North Texas in 1988–1989. He is with the Institute
of Information Management, National Chiao Tung University, Hsinchu, Taiwan, R.O.C. 相似文献
45.
A survey of CSCW systems 总被引:4,自引:0,他引:4
Tom Rodden 《Interacting with computers》1991,3(3):319-353
Over the last decade, computer supported cooperative work (CSCW) has emerged as an identifiable research area that focuses on the role of the computer in group work. CSCW is a generic term which combines the understanding of the nature of group working with the enabling technologies of computer networking, systems support and applications. The paper examines the classes of system which have emerged to support cooperative working. A framework for characterising and describing CSCW systems is presented and four major classes of cooperative system identified. Each of these classes of cooperative system are examined highlighting their general characteristics and applicability to CSCW. 相似文献
46.
本文给出了一种椭圆弧长的作图求解方法,即由作图求得椭圆弧长的近似值。通过对100个椭圆弧长的求解结果表明,由此方法求得的椭圆弧长的误差甚小,从而在相当高的精度范围内,提供了一种工程中适用并且简单易行的求解椭圆弧长的方法。 相似文献
47.
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49.
We deal with a complex game between Alice and Bob where each contender’s probability of victory grows monotonically by unknown amounts with the resources employed. For a fixed effort on Alice’s part, Bob increases his resources on the basis of the results for each round (victory, tie or defeat) with the aim of reducing the probability of defeat to below a given threshold. We read this goal in terms of computing a confidence interval for the probability of losing and realize that the moves in some contests may bring in an indeterminacy trap: in certain games Bob cannot simultaneously have both a low probability-of-defeat measure and a narrow confidence interval. We use the inferential mechanism called twisting argument to compute the above interval on the basis of two joint statistics. Careful use of such statistics allows us to avoid indeterminacy. 相似文献
50.
Eddie Cheng 《Information Sciences》2007,177(22):4877-4882
We prove that when linearly many vertices are deleted in a Cayley graph generated by a transposition tree, the resulting graph has a large connected component containing almost all remaining vertices. 相似文献