- Email: [email protected]
An alternate approach to syndrome algebra for diagnostics
996
World Abstracts on Microelectronics and Reliability
Test device structures for integrated circuit design, process technology development and evaluation. A. SRtVASTAVA. Microelectron. Reliab. 22 (2), 195 (1982). In the present paper, mask contours of npn transistors, pnp lateral transistors, diffused and pinch resistors, bridge and Greek cross sheet resistors, metal to doped silicon region contact resistors, parasitic pnp transistors, test diodes and alignment marks have been drawn (500 x ) for the development and testing of integrated circuit design and technology. The layout design of devices is based on 10 lam design rules with defined m i n i m u m dimensions and clearances in order to avoid the failure of the circuit due to technological inaccuracies. Devices could be easily designed, fabricated and performance evaluated in a fairly good R & D set-up having semiconductor device fabrication facilities. Optimal structure of sensor systems composed of nonidentical sensors. TAKEHISA KOHDA, HIROMITSU KUMAMOTO,KOICHI INOUE and ISAO TAKAMI. Microelectron. Reliab. 22 (3), 445 0982). The sensor system has two types of contradictory failures; a fail-dangerous failure and a fail-safe failure. A method of obtaining the optimal structure is developed for the sensor system which is composed of general components. The optimal structure minimizes an expected damage, considering all possible Boolean structures including noncoherent systems. A simple optimality criterion is obtained and several properties of the optimal structures are derived; a noncoherent structure can be optimal in some cases. A simple systematic search algorithm can be used effectively to determine the optimal system. Analytic solutions are obtained for systems composed of identical components. Illustrative examples are given. Operational repairable equipments and the Duane model. A. C. DURR. Microeleetron. Reliab. 22 (3), 379 (1982). For many years, the assessment of the rate of reliability growth during the development of repairable equipments has been carried out using the Duane model. As part of a design-tolife-cycle cost study, it was required to determine whether the Duane model was also applicable to operational equipment data. Observation of data trends indicated that the majority of the 370 data sets tested possessed non-constant failure rates. Further analysis revealed nearly 80 ~o of the data sets accepted a Weibull repairable model (which is equivalent to Duane). However, tilting the model to the data using either or both the least squares and m a x i m u m likelihood regression methods produced problems which led to the conclusion that the Duane model was unsuitable for use on operational failure data. On creating a reliable programming environment. INDER M. Sol. Microelectron. Reliah. 22 (4), 711 (1982). Many organizations are presently working to develop a software development methodology special to their own needs. The methodology must be supported by automated tools that improve the productivity of both the individual developer and the development team. This collection of tools and the way in which they are used constitute what has been called a "programming environment", since most automated tools are aimed at the coding and implementation phases of software development. The task of creating effective environments is quite difficult because it is t a n t a m o u n t to understanding the fundamental nature of software processes. This paper is intended to give insight into the characteristics of existing program development environments and to point the way towards some desirable characteristics which may lead to the creation of reliable and cost-effective future programming environments. Petri net as a modelling tool. G. S. HURA. Microelectron. Reliab. 22 (3), 433 (1982). Over the last decade, Petri nets have emerged as a most suitable, powerful and widely acceptable modelling tool for representing and studying the
asynchronous concurrent hardware (or software) systems/ processes. Petri nets can be viewed as formal automata or as an automation which can generate the formal languages or a model to analyse and synthesize various kinds of systems. The structure of Petri nets, their markings, extensions and subclasses are briefly discussed. Several examples of Petri net models of computer hardware and software are presented. Various applications of reachability concepts are also given. A Petri net approach to enumerate all system success paths for reliability evaluation of a complex system. G. S. HURA. Microelectron. Reliab. 22 (3), 427 (1982). A Petri net approach to enumerate all system success paths between a specified pair of nodes is presented. The proposed technique requires only vector additions on a single matrix. It is simple and can easily be computerized. A Kolmogorov-Smirnov goodness-of-fit test for the twoparameter Weibuli distribution when the parameters are estimated from the data. MAJOR F. G. PARSONS and P. H. WIRSCHING. Microelectron. Reliab. 22 (2), 163 (1982). The critical values presented in the standard tables of the K o l m o g o r o v - S m i r n o v statistic do not apply when one or more of the parameters must be estimated from the data. However, it is possible, using Monte Carlo methods, to construct a table of this statistic for use when the parameters must be estimated from the data. A table of values for use with the two-parameter Weibull is presented herein. Moreover, a Monte Carlo study of the power of the test against commonly used statistical models is presented. Furthermore, additional studies suggest that the same table can be used for the normal, lognormal and Gumbel (Extreme Value Distribution, Type I of Maxima) distributions. An alternate approach to syndrome algebra for diagnostics. WINFR|D SCHNEEWEISS. Microelectron. Reliab. 22 (3), 569 (1982). It is shown that the syndrome of a Boolean function F (for diagnostics) can be nicely modelled to be F in a special pseudo-Boolean algebra at that point in state space where all variables are equal to ½ or as the probability of F being 1 in case all its variables appear with probability ½. Results are useful wherever the number of minterms of a switching function is needed. Preventive maintenance of a l-unit system with two types of repair. MASASIKOWADAand ATHUSHIBANDO.Microeleetron. Reliab. 22 (2), 287 (1982). This paper deals with a 1-unit system with two types of repair which consist of repair I and repair II. After performing repair I, the age of the unit becomes &, if the total a m o u n t of operating time before the failure is t. Repair I is made at each k-th failure (k 4: nN, n = l, 2 . . . . ). Repair II is made at each nN-th failure and after performing it, the unit is as good as new. This model is described as a regenerative process, and pointwise availability, long-run availability, and its optimization are given with a numerical example. Une modelisation Bayesienne du taux de defaillance en fiabilite. J. RINGLER. Microelectron. Reliab. 22 (3), 385 (1982) (in French). The classical approach in reliability in which no difference is made between the failure rates of various electronic components making up an assumed homogeneous batch, leads to some formal difficulties which will be demonstrated. A new approach is proposed in which each component in the batch is characterized by its own "stress resistance capability". This approach leads us to postulate the existence of an individual "lambda" attached to each component and thus that of a statistical distribution of the "lambdas" at batch level. Taking this distribution as a distribution a priori, a bayesian treatment is then applied. The result is a formalization of an unconditional failure rate reflecting the mean failure rate of the batch considered. Choosing a priori a g a m m a type distribution (justified by
World Abstracts on Microelectronics and Reliability
Test device structures for integrated circuit design, process technology development and evaluation. A. SRtVASTAVA. Microelectron. Reliab. 22 (2), 195 (1982). In the present paper, mask contours of npn transistors, pnp lateral transistors, diffused and pinch resistors, bridge and Greek cross sheet resistors, metal to doped silicon region contact resistors, parasitic pnp transistors, test diodes and alignment marks have been drawn (500 x ) for the development and testing of integrated circuit design and technology. The layout design of devices is based on 10 lam design rules with defined m i n i m u m dimensions and clearances in order to avoid the failure of the circuit due to technological inaccuracies. Devices could be easily designed, fabricated and performance evaluated in a fairly good R & D set-up having semiconductor device fabrication facilities. Optimal structure of sensor systems composed of nonidentical sensors. TAKEHISA KOHDA, HIROMITSU KUMAMOTO,KOICHI INOUE and ISAO TAKAMI. Microelectron. Reliab. 22 (3), 445 0982). The sensor system has two types of contradictory failures; a fail-dangerous failure and a fail-safe failure. A method of obtaining the optimal structure is developed for the sensor system which is composed of general components. The optimal structure minimizes an expected damage, considering all possible Boolean structures including noncoherent systems. A simple optimality criterion is obtained and several properties of the optimal structures are derived; a noncoherent structure can be optimal in some cases. A simple systematic search algorithm can be used effectively to determine the optimal system. Analytic solutions are obtained for systems composed of identical components. Illustrative examples are given. Operational repairable equipments and the Duane model. A. C. DURR. Microeleetron. Reliab. 22 (3), 379 (1982). For many years, the assessment of the rate of reliability growth during the development of repairable equipments has been carried out using the Duane model. As part of a design-tolife-cycle cost study, it was required to determine whether the Duane model was also applicable to operational equipment data. Observation of data trends indicated that the majority of the 370 data sets tested possessed non-constant failure rates. Further analysis revealed nearly 80 ~o of the data sets accepted a Weibull repairable model (which is equivalent to Duane). However, tilting the model to the data using either or both the least squares and m a x i m u m likelihood regression methods produced problems which led to the conclusion that the Duane model was unsuitable for use on operational failure data. On creating a reliable programming environment. INDER M. Sol. Microelectron. Reliah. 22 (4), 711 (1982). Many organizations are presently working to develop a software development methodology special to their own needs. The methodology must be supported by automated tools that improve the productivity of both the individual developer and the development team. This collection of tools and the way in which they are used constitute what has been called a "programming environment", since most automated tools are aimed at the coding and implementation phases of software development. The task of creating effective environments is quite difficult because it is t a n t a m o u n t to understanding the fundamental nature of software processes. This paper is intended to give insight into the characteristics of existing program development environments and to point the way towards some desirable characteristics which may lead to the creation of reliable and cost-effective future programming environments. Petri net as a modelling tool. G. S. HURA. Microelectron. Reliab. 22 (3), 433 (1982). Over the last decade, Petri nets have emerged as a most suitable, powerful and widely acceptable modelling tool for representing and studying the
asynchronous concurrent hardware (or software) systems/ processes. Petri nets can be viewed as formal automata or as an automation which can generate the formal languages or a model to analyse and synthesize various kinds of systems. The structure of Petri nets, their markings, extensions and subclasses are briefly discussed. Several examples of Petri net models of computer hardware and software are presented. Various applications of reachability concepts are also given. A Petri net approach to enumerate all system success paths for reliability evaluation of a complex system. G. S. HURA. Microelectron. Reliab. 22 (3), 427 (1982). A Petri net approach to enumerate all system success paths between a specified pair of nodes is presented. The proposed technique requires only vector additions on a single matrix. It is simple and can easily be computerized. A Kolmogorov-Smirnov goodness-of-fit test for the twoparameter Weibuli distribution when the parameters are estimated from the data. MAJOR F. G. PARSONS and P. H. WIRSCHING. Microelectron. Reliab. 22 (2), 163 (1982). The critical values presented in the standard tables of the K o l m o g o r o v - S m i r n o v statistic do not apply when one or more of the parameters must be estimated from the data. However, it is possible, using Monte Carlo methods, to construct a table of this statistic for use when the parameters must be estimated from the data. A table of values for use with the two-parameter Weibull is presented herein. Moreover, a Monte Carlo study of the power of the test against commonly used statistical models is presented. Furthermore, additional studies suggest that the same table can be used for the normal, lognormal and Gumbel (Extreme Value Distribution, Type I of Maxima) distributions. An alternate approach to syndrome algebra for diagnostics. WINFR|D SCHNEEWEISS. Microelectron. Reliab. 22 (3), 569 (1982). It is shown that the syndrome of a Boolean function F (for diagnostics) can be nicely modelled to be F in a special pseudo-Boolean algebra at that point in state space where all variables are equal to ½ or as the probability of F being 1 in case all its variables appear with probability ½. Results are useful wherever the number of minterms of a switching function is needed. Preventive maintenance of a l-unit system with two types of repair. MASASIKOWADAand ATHUSHIBANDO.Microeleetron. Reliab. 22 (2), 287 (1982). This paper deals with a 1-unit system with two types of repair which consist of repair I and repair II. After performing repair I, the age of the unit becomes &, if the total a m o u n t of operating time before the failure is t. Repair I is made at each k-th failure (k 4: nN, n = l, 2 . . . . ). Repair II is made at each nN-th failure and after performing it, the unit is as good as new. This model is described as a regenerative process, and pointwise availability, long-run availability, and its optimization are given with a numerical example. Une modelisation Bayesienne du taux de defaillance en fiabilite. J. RINGLER. Microelectron. Reliab. 22 (3), 385 (1982) (in French). The classical approach in reliability in which no difference is made between the failure rates of various electronic components making up an assumed homogeneous batch, leads to some formal difficulties which will be demonstrated. A new approach is proposed in which each component in the batch is characterized by its own "stress resistance capability". This approach leads us to postulate the existence of an individual "lambda" attached to each component and thus that of a statistical distribution of the "lambdas" at batch level. Taking this distribution as a distribution a priori, a bayesian treatment is then applied. The result is a formalization of an unconditional failure rate reflecting the mean failure rate of the batch considered. Choosing a priori a g a m m a type distribution (justified by