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Network reliability evaluation using probability expressions
World Abstracts on Microelectronics and Reliability
Derivation of an exact expression for mean time to repair. STEVEN A. LAPP. IEEE Trans. Reliab. R-35 (3), 336 (1986). The mean time to repair for a failed component is a necessary number for availability calculations. For a device with a constant failure intensity, one half of the time between tests is often taken to be the mean time to repair. This is an approximation. This paper derives an exact expression for mean time to repair and discusses its limiting behavior. For constant failure intensity, approximating the mean time to repair by one half of the test interval is valid when the product of failure intensity and test interval is small. As this product increases, mean time to repair approaches the "test interval" minus the "mean time to failure". An example illustrates these concepts. Standby redundancy in reliability--a review. ROBERT D. YEAROUT, PRABHAKER REDDY and DORIS LLOYD GROSH. IEEE Trans. Reliab. R-35 (3), 285 (1986). Redundancy is used to improve the reliability of a system beyond that obtained by redesigning the system or selecting better parts. This paper reviews the literature to standby redundancy over the past ten years. Rectifying inspection for defects. WILLIAM C. GUENTHER. IEEE Trans. Reliab. R-35 (3), 344 (1986). Several kinds of rectifying inspection plans based on defects per unit are considered. Plans are found by minimizing the average cost per lot, usually subject to a side condition. For every situation the desired sampling plan can be found easily with a computer program. The independence assumption for a series or parallel system when component lifetimes are exponential. JOHN P. KLEIN and M. L. MOESCHBERGER.IEEE Trans. Reliab. R-35 (3), 330 (1986). A common assumption made in modeling system life from series and parallel systems is that the component lives are independent. This study investigates the magnitude of the errors one may incur by erroneously assuming the component lifetimes have independent exponential distributions when in fact the lifetimes follow the bivariate exponential distribution of Marshall & Olkin (series or parallel systems) of that of Freund (parallel systems). Software for reliability testing of computer peripherals: a case history. PHILIP R. JOSLIN. IEEE Trans. Reliab. R-35 (3), 279 (1986). This article addresses: (1) the problem of inadequate software for the reliability testing of computer peripherals, and (2) the development and use of a software package specifically designed for reliability testing of disk drive peripherals. The software package enables one to carry out controlled reliability testing of disk drive peripherals. Necessary data for statistical calculation are available when needed and in the detail required. Non-drive errors can be isolated a n d not allowed to distort test results. The soundness of data collected allows for long-term testing under changing conditions to proceed with assurance of accuracy. Product reliability and thereby customer satisfaction can be more fully assured. The creation of the software also provided an outline of a sound methodology for future reliability software development. This methodology has continued to be employed within Intel and at a number of the vendors supplying Intel with disk drive peripherals. Efficient algorithms for reliability analysis of planar networks--a survey. THEMISTOCLES POLITOF and A. SATYANARAYANA.IEEE Trans. Reliab. R-35 (3), 252 (1986). We survey some recent polynomial-time algorithms for the exact computation of network reliability. The algorithms apply to several classes of planar networks, which include series-parallel, inner-cycle-free, inner-four-cycle-free and planar cube-free. We describe these classes and discuss the related polynomial algorithms for computing their reliability.
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Network reliability evaluation using probability expressions. W. H. DEBANYJR, P. K. VARSHNEYand C. R. P. HARTMANN. IEEE Trans. Reliab. R-35 (2), 161 (1986). The terminal-pair reliability of a graph (network) is evaluated by means of probability expressions. These expressions result from a transformation of Boolean expressions from the Boolean domain into the probabilistic domain. Basic operations on probability expressions are shown, and a data representation is given for automation of the procedure. The performance of this procedure is compared with other published results. Two new measures, PRI and POST, give relationships between a network's terminal-pair reliability and individual element reliabilities, and derive an element ordering for network diagnosis. These measures can be computed easily using probability expressions. Modeling, metamodeling, and taxonomy of system failures. JOHN P. VAN GIGCH. IEEE Trans. Reliab. R-35 (2), 131 (1986). A methodology, called the metasystem approach, is used to discuss modeling and metamodeling of systems failures. The methodology is based on a hierarchy of control where decisional and behavioral processes are differentiated on the basis of domain and logic levels. Yield and performance enhancement through redundancy in VLSI and WSI multi-processor systems. ISRAEL KOREN and DH1RAJ K. PRADI-IAN. Proc. IEEE 74 (5), 699 (1986). New challenges have been brought to fault-tolerant computing and processor architecture research because of developments in IC technology. One emerging area is development of architectures, built by interconnecting a large number of processing elements on a single chip or wafer. Two important areas, related to such VLSI processor arrays, are the focus of this paper; they are fault-tolerance and yield improvement techniques. Fault tolerance in these VLSI processor arrays is of real practical significance; it provides for much-needed reliability improvement. Therefore, we first describe the underlying concepts of fault tolerance at work in these multiprocessor systems. These percepts are useful to then present certain techniques that will incorporate fault tolerance integrally into the design. In the second part of the paper we discuss models that evaluate how yield enhancement and reliability improvement may be achieved by certain fault-tolerant techniques. On the relationship between two fatigue-life models. A. F. DESMOND. IEEE Trans. Reliab. R-35 (2), 167 (1986). The relationship between two fatigue life distributions, namely the Birnbaum-Saunders and the inverse Gaussian, is further investigated. An intimate connection exists between the two models, viz. the Birnbuam-Saunders is a mixture of two probability distributions: (1) an inverse Gaussian random variable and (2) the reciprocal of an inverse Gaussian random variable. Advantages and disadvantages of the two distributions are discussed. The arguments favour the Birnbaum-Saunders distribution from a stochastic modeling point of view, whereas the inverse Gaussian distribution seems to be the more attractive of the two with respect to statistical analysis and analysis of censored data. Lifetime distribution identities. LAWRENCEM. LEEMIS.IEEE Trans. Reliab. R-35 (2), 170 (1986). Five ways of representing the distribution of a continuous non-negative random variable T are used extensively in the reliability literature: the probability density function, the reliability (survivor function), the hazard rate, the cumulative hazard function, and the mean residual life function. Properties, identities, and intuitive interpretations of the five representations are discussed. Several examples are given. Although there are other functions, such as normalized mean residual fife for studying replacement policies, these five
Derivation of an exact expression for mean time to repair. STEVEN A. LAPP. IEEE Trans. Reliab. R-35 (3), 336 (1986). The mean time to repair for a failed component is a necessary number for availability calculations. For a device with a constant failure intensity, one half of the time between tests is often taken to be the mean time to repair. This is an approximation. This paper derives an exact expression for mean time to repair and discusses its limiting behavior. For constant failure intensity, approximating the mean time to repair by one half of the test interval is valid when the product of failure intensity and test interval is small. As this product increases, mean time to repair approaches the "test interval" minus the "mean time to failure". An example illustrates these concepts. Standby redundancy in reliability--a review. ROBERT D. YEAROUT, PRABHAKER REDDY and DORIS LLOYD GROSH. IEEE Trans. Reliab. R-35 (3), 285 (1986). Redundancy is used to improve the reliability of a system beyond that obtained by redesigning the system or selecting better parts. This paper reviews the literature to standby redundancy over the past ten years. Rectifying inspection for defects. WILLIAM C. GUENTHER. IEEE Trans. Reliab. R-35 (3), 344 (1986). Several kinds of rectifying inspection plans based on defects per unit are considered. Plans are found by minimizing the average cost per lot, usually subject to a side condition. For every situation the desired sampling plan can be found easily with a computer program. The independence assumption for a series or parallel system when component lifetimes are exponential. JOHN P. KLEIN and M. L. MOESCHBERGER.IEEE Trans. Reliab. R-35 (3), 330 (1986). A common assumption made in modeling system life from series and parallel systems is that the component lives are independent. This study investigates the magnitude of the errors one may incur by erroneously assuming the component lifetimes have independent exponential distributions when in fact the lifetimes follow the bivariate exponential distribution of Marshall & Olkin (series or parallel systems) of that of Freund (parallel systems). Software for reliability testing of computer peripherals: a case history. PHILIP R. JOSLIN. IEEE Trans. Reliab. R-35 (3), 279 (1986). This article addresses: (1) the problem of inadequate software for the reliability testing of computer peripherals, and (2) the development and use of a software package specifically designed for reliability testing of disk drive peripherals. The software package enables one to carry out controlled reliability testing of disk drive peripherals. Necessary data for statistical calculation are available when needed and in the detail required. Non-drive errors can be isolated a n d not allowed to distort test results. The soundness of data collected allows for long-term testing under changing conditions to proceed with assurance of accuracy. Product reliability and thereby customer satisfaction can be more fully assured. The creation of the software also provided an outline of a sound methodology for future reliability software development. This methodology has continued to be employed within Intel and at a number of the vendors supplying Intel with disk drive peripherals. Efficient algorithms for reliability analysis of planar networks--a survey. THEMISTOCLES POLITOF and A. SATYANARAYANA.IEEE Trans. Reliab. R-35 (3), 252 (1986). We survey some recent polynomial-time algorithms for the exact computation of network reliability. The algorithms apply to several classes of planar networks, which include series-parallel, inner-cycle-free, inner-four-cycle-free and planar cube-free. We describe these classes and discuss the related polynomial algorithms for computing their reliability.
937
Network reliability evaluation using probability expressions. W. H. DEBANYJR, P. K. VARSHNEYand C. R. P. HARTMANN. IEEE Trans. Reliab. R-35 (2), 161 (1986). The terminal-pair reliability of a graph (network) is evaluated by means of probability expressions. These expressions result from a transformation of Boolean expressions from the Boolean domain into the probabilistic domain. Basic operations on probability expressions are shown, and a data representation is given for automation of the procedure. The performance of this procedure is compared with other published results. Two new measures, PRI and POST, give relationships between a network's terminal-pair reliability and individual element reliabilities, and derive an element ordering for network diagnosis. These measures can be computed easily using probability expressions. Modeling, metamodeling, and taxonomy of system failures. JOHN P. VAN GIGCH. IEEE Trans. Reliab. R-35 (2), 131 (1986). A methodology, called the metasystem approach, is used to discuss modeling and metamodeling of systems failures. The methodology is based on a hierarchy of control where decisional and behavioral processes are differentiated on the basis of domain and logic levels. Yield and performance enhancement through redundancy in VLSI and WSI multi-processor systems. ISRAEL KOREN and DH1RAJ K. PRADI-IAN. Proc. IEEE 74 (5), 699 (1986). New challenges have been brought to fault-tolerant computing and processor architecture research because of developments in IC technology. One emerging area is development of architectures, built by interconnecting a large number of processing elements on a single chip or wafer. Two important areas, related to such VLSI processor arrays, are the focus of this paper; they are fault-tolerance and yield improvement techniques. Fault tolerance in these VLSI processor arrays is of real practical significance; it provides for much-needed reliability improvement. Therefore, we first describe the underlying concepts of fault tolerance at work in these multiprocessor systems. These percepts are useful to then present certain techniques that will incorporate fault tolerance integrally into the design. In the second part of the paper we discuss models that evaluate how yield enhancement and reliability improvement may be achieved by certain fault-tolerant techniques. On the relationship between two fatigue-life models. A. F. DESMOND. IEEE Trans. Reliab. R-35 (2), 167 (1986). The relationship between two fatigue life distributions, namely the Birnbaum-Saunders and the inverse Gaussian, is further investigated. An intimate connection exists between the two models, viz. the Birnbuam-Saunders is a mixture of two probability distributions: (1) an inverse Gaussian random variable and (2) the reciprocal of an inverse Gaussian random variable. Advantages and disadvantages of the two distributions are discussed. The arguments favour the Birnbaum-Saunders distribution from a stochastic modeling point of view, whereas the inverse Gaussian distribution seems to be the more attractive of the two with respect to statistical analysis and analysis of censored data. Lifetime distribution identities. LAWRENCEM. LEEMIS.IEEE Trans. Reliab. R-35 (2), 170 (1986). Five ways of representing the distribution of a continuous non-negative random variable T are used extensively in the reliability literature: the probability density function, the reliability (survivor function), the hazard rate, the cumulative hazard function, and the mean residual life function. Properties, identities, and intuitive interpretations of the five representations are discussed. Several examples are given. Although there are other functions, such as normalized mean residual fife for studying replacement policies, these five