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Manufacturing system control with Petri nets in cellular manufacturing systems
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World Abstracts on Microelectronics and Reliability
cantly. The increased cost associated with acquiring the additional spares was virtually negligible when compared to the MSE procurement cost. Exact reliability formula for consecutive-k-out-of-n:F systems with homogeneous Markov dependence. GUANOPI~GGE and LISHU WANG. IEEE Trans. Reliab. 39(5), 600 (1990). There are direct and recursive methods to compute the reliability for a consecutive-k-out-of-n:F system where the components are mutually statistically independent. Papastavridis & Lambiris give a recursive method to compute the reliability for a consecutive-k-out-of-n:F system with Markov-dependent components. This paper gives a direct exact method to compute the reliability for a consecutive-kout-of-n :F system with homogeneous Markov dependence. A linear-time algorithm to compute the reliability of planar cube-free networks. THEMISTOCLESPOLITOF and A. SATYANARAYANA.IEEE Trans. Reliab. 39(5), 557 (1990). A planar graph G = (V, E) is a cube-free graph (CF-graph) if it has no subgraph homeomorphic to the cube. The cube is the graph whose vertices and edges are the vertices and edges of the 3-dimensional geometric cube. The all-terminal reliability of a graph G, whose edges can fail (with known probabilities) is the probability that G is connected. The problem of computing the all-terminal reliability of a general graph is NP-hard. This paper presents an O(I VI) time algorithm to compute the all-terminal reliability of CFgraphs. Reliability demonstration test and OC curves for attribute data. TONI LIN and MICHAELD. HOLBROOK. Computers ind. Engng 20(1), 1 (1991). Binomial reliability test plan procedures are widely used to demonstrate the satisfaction of the contractual reliability requirements. In this paper, a computer program for binomial test plans is developed to provide the user with desired information such as sample size, confidence level, designed reliability goal, and number of failures permitted in a more efficient and timely manner. An operating characteristic curve can be plotted by using the data file generated from the program to evaluate the test plans. On the increase of system reliability by parallel redundancy. K. SHENand M. XIE. IEEE Trans. Reliab. 39(5), 607 (1990). Parallel redundancy is a well known technique in improving system reliability. Adding parallel redundancy to different components generally yields different system reliability improvements. This paper investigates the effect of such parallel redundancy upon system reliability when applied at various places and in various systems. Thereafter, the problem of how to choose components for parallel redundancy is studied and some results are given. Some examples are presented to illustrate the approach. Petri Nets in dynamic process planning. K. SRIHAR1and C. R. EMERSON. Computers ind. Engng 19(1-4), 447 (1990). A framework for combining Petri Nets with Computer Aided Process Planning (CAPP) systems is presented. The Petri Nets are used to provide realtime facility status information while the CAPP system is used to generate the revised process plans. Combining these two methodologies overcomes most of the weaknesses with the traditional CAPP system. The result is a dynamic, realtime CAPP system. Manufacturing system control with Petri nets in cellular manufacturing systems. SHENG-HSIENTENGand J. T. BLACK. Computers ind. Engng 19(1-4), 150 (1990). This paper discusses the use of Petri nets in system control. A Petri net model is developed for a Cellular Manufacturing System
(CMS). The system control heuristics can be generated based on this Petri net model. Some of the controls of the cell operation are demonstrated through the application of Petri nets. These controls include the control of work-inprogress (WIP) inventory within cells and stock-on-hand (SOH) in the cells, the control of part-changes, and the control of disturbance handling. A redundant metal-polyimide thin film interconnection process for wafer scale dimensions. TIMOTHY L. MICHALKA, WIESLAW LUKASZEKand JANES D. MEINDL. IEEE Trans. Semicond. Mfg 3(4), 158 (1990). The expected defect modes, and the predominance of a single mode, for wafer scale interconnections produced using typical thin film processing techniques are discussed. A process using redundancy in the vertical direction to eliminate the dominant defect mode is presented with calculations illustrating potential yield improvements. Experimental results of an implementation of the redundancy technique using a lift-off process with polyimide dielectric are presented. The process uses a repeatable element step capable of producing signal layers, via studs, or reference planes while maintaining good planarity. The basic precepts of the redundant process are verified. Defect cluster analysis for wafer-scale integration. PAUL R. PUKITE and CLAUDE L. BERMAN. IEEE Trans. Semicond. Mfg 3(3), 128 (1990). Redundant circuit yield prediction is vital for determining the cost-effectiveness of wafer-scale integration (WSI) and other fault-tolerant fabrication technologies. The yield of redundant circuits is critically dependent not only on the average defect densities that occur in the fabrication process but also on the spatial distribution of these defects. In particular, clustered defects are known to be important yield detractors of fault-tolerant circuits. In this study, we show that correlation function techniques can be used to characterize defect clustering and suggest it can be used to predict yield of different faulttolerant configurations. Examples are taken from available defect maps and wafer particle detection experiments to demonstrate the capabilities of the correlation function approach. Equilibrium distributions of finite-state Markov processes. IEEE Trans. Reliab. 39(5), 592 (1990). Very simple methods, using APL, are presented for computing equilibrium distributions of finite-state Markov processes in continuous time and in discrete time, viz., Markov chains. These use the APL domino function which takes a least-squares approach which is efficient with systems of up to 50 states, probably more. This approach can also be used to solve for mean interval occupanices. We do not suggest the least squares solution be implemented in traditional languages like FORTRAN simply for the purpose of finding equilibrium distributions, for which the state reduction method (2) is simpler. However, if you have APL available the hard work has been done for you and the methods described here provide accurate and extremely simple solutions for discrete or continuous time models. More importantly, the APL domino function leads to a powerful and simple computation of mean interval occupancies, and, hence, availabilities. Availability formulae for standby systems of similar units that are preventively maintained. TERJE AVEN. IEEE Trans. Reliab. 39(5), 603 (1990). This paper presents some simple approximation formulae for the availability of standby redundant systems comprising similar units that are preventively maintained. The formulae are established using standard Markov theory. A number of simulations have been performed in order to evaluate the formulae. The simulations show that the formulae give very good approximations for various preventive maintenance regimes.
World Abstracts on Microelectronics and Reliability
cantly. The increased cost associated with acquiring the additional spares was virtually negligible when compared to the MSE procurement cost. Exact reliability formula for consecutive-k-out-of-n:F systems with homogeneous Markov dependence. GUANOPI~GGE and LISHU WANG. IEEE Trans. Reliab. 39(5), 600 (1990). There are direct and recursive methods to compute the reliability for a consecutive-k-out-of-n:F system where the components are mutually statistically independent. Papastavridis & Lambiris give a recursive method to compute the reliability for a consecutive-k-out-of-n:F system with Markov-dependent components. This paper gives a direct exact method to compute the reliability for a consecutive-kout-of-n :F system with homogeneous Markov dependence. A linear-time algorithm to compute the reliability of planar cube-free networks. THEMISTOCLESPOLITOF and A. SATYANARAYANA.IEEE Trans. Reliab. 39(5), 557 (1990). A planar graph G = (V, E) is a cube-free graph (CF-graph) if it has no subgraph homeomorphic to the cube. The cube is the graph whose vertices and edges are the vertices and edges of the 3-dimensional geometric cube. The all-terminal reliability of a graph G, whose edges can fail (with known probabilities) is the probability that G is connected. The problem of computing the all-terminal reliability of a general graph is NP-hard. This paper presents an O(I VI) time algorithm to compute the all-terminal reliability of CFgraphs. Reliability demonstration test and OC curves for attribute data. TONI LIN and MICHAELD. HOLBROOK. Computers ind. Engng 20(1), 1 (1991). Binomial reliability test plan procedures are widely used to demonstrate the satisfaction of the contractual reliability requirements. In this paper, a computer program for binomial test plans is developed to provide the user with desired information such as sample size, confidence level, designed reliability goal, and number of failures permitted in a more efficient and timely manner. An operating characteristic curve can be plotted by using the data file generated from the program to evaluate the test plans. On the increase of system reliability by parallel redundancy. K. SHENand M. XIE. IEEE Trans. Reliab. 39(5), 607 (1990). Parallel redundancy is a well known technique in improving system reliability. Adding parallel redundancy to different components generally yields different system reliability improvements. This paper investigates the effect of such parallel redundancy upon system reliability when applied at various places and in various systems. Thereafter, the problem of how to choose components for parallel redundancy is studied and some results are given. Some examples are presented to illustrate the approach. Petri Nets in dynamic process planning. K. SRIHAR1and C. R. EMERSON. Computers ind. Engng 19(1-4), 447 (1990). A framework for combining Petri Nets with Computer Aided Process Planning (CAPP) systems is presented. The Petri Nets are used to provide realtime facility status information while the CAPP system is used to generate the revised process plans. Combining these two methodologies overcomes most of the weaknesses with the traditional CAPP system. The result is a dynamic, realtime CAPP system. Manufacturing system control with Petri nets in cellular manufacturing systems. SHENG-HSIENTENGand J. T. BLACK. Computers ind. Engng 19(1-4), 150 (1990). This paper discusses the use of Petri nets in system control. A Petri net model is developed for a Cellular Manufacturing System
(CMS). The system control heuristics can be generated based on this Petri net model. Some of the controls of the cell operation are demonstrated through the application of Petri nets. These controls include the control of work-inprogress (WIP) inventory within cells and stock-on-hand (SOH) in the cells, the control of part-changes, and the control of disturbance handling. A redundant metal-polyimide thin film interconnection process for wafer scale dimensions. TIMOTHY L. MICHALKA, WIESLAW LUKASZEKand JANES D. MEINDL. IEEE Trans. Semicond. Mfg 3(4), 158 (1990). The expected defect modes, and the predominance of a single mode, for wafer scale interconnections produced using typical thin film processing techniques are discussed. A process using redundancy in the vertical direction to eliminate the dominant defect mode is presented with calculations illustrating potential yield improvements. Experimental results of an implementation of the redundancy technique using a lift-off process with polyimide dielectric are presented. The process uses a repeatable element step capable of producing signal layers, via studs, or reference planes while maintaining good planarity. The basic precepts of the redundant process are verified. Defect cluster analysis for wafer-scale integration. PAUL R. PUKITE and CLAUDE L. BERMAN. IEEE Trans. Semicond. Mfg 3(3), 128 (1990). Redundant circuit yield prediction is vital for determining the cost-effectiveness of wafer-scale integration (WSI) and other fault-tolerant fabrication technologies. The yield of redundant circuits is critically dependent not only on the average defect densities that occur in the fabrication process but also on the spatial distribution of these defects. In particular, clustered defects are known to be important yield detractors of fault-tolerant circuits. In this study, we show that correlation function techniques can be used to characterize defect clustering and suggest it can be used to predict yield of different faulttolerant configurations. Examples are taken from available defect maps and wafer particle detection experiments to demonstrate the capabilities of the correlation function approach. Equilibrium distributions of finite-state Markov processes. IEEE Trans. Reliab. 39(5), 592 (1990). Very simple methods, using APL, are presented for computing equilibrium distributions of finite-state Markov processes in continuous time and in discrete time, viz., Markov chains. These use the APL domino function which takes a least-squares approach which is efficient with systems of up to 50 states, probably more. This approach can also be used to solve for mean interval occupanices. We do not suggest the least squares solution be implemented in traditional languages like FORTRAN simply for the purpose of finding equilibrium distributions, for which the state reduction method (2) is simpler. However, if you have APL available the hard work has been done for you and the methods described here provide accurate and extremely simple solutions for discrete or continuous time models. More importantly, the APL domino function leads to a powerful and simple computation of mean interval occupancies, and, hence, availabilities. Availability formulae for standby systems of similar units that are preventively maintained. TERJE AVEN. IEEE Trans. Reliab. 39(5), 603 (1990). This paper presents some simple approximation formulae for the availability of standby redundant systems comprising similar units that are preventively maintained. The formulae are established using standard Markov theory. A number of simulations have been performed in order to evaluate the formulae. The simulations show that the formulae give very good approximations for various preventive maintenance regimes.