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Stochastic theory of a fluid model of producers and consumers coupled by a buffer

Published online by Cambridge University Press:  01 July 2016

Debasis Mitra*
Affiliation:
AT & T Bell Laboratories
*
Postal address: AT & T Bell Laboratories, Room 2C125, 600 Mountain Avenue, Murray Hill, NJ 07974-2070, USA.

Abstract

This paper analyzes, derives efficient computational procedures and numerically investigates the following fluid model which is of interest in manufacturing and communications: m producing machines supply a buffer, n consuming machines feed off it. Each machine independently alternates between exponentially distributed random periods in the ‘in service' and ‘failed' states. Producers/consumers have their own failure/repair rates and working capacities. When the buffer is either full or empty some of the machines in service are not utilized to capacity; otherwise they are fully utilized. Our main result is for the state distribution of the Markovian system in equilibrium which is the solution of a system of differential equations. The spectral expansion for its solution is obtained. Two important decompositions are obtained: the eigenvectors have the Kronecker-product form in lower-dimensional vectors; the characteristic polynomial is factored with each factor an explicitly given polynomial of degree at most 4. All eigenvalues are real. For each of various cases of the model, a system of linear equations is derived from the boundary conditions; their solution complete the spectral expansion. The count in operations of the entire procedure is O(m3n3): independence from buffer size exemplifies an important attraction of fluid models. Computations have revealed several interesting features, such as the benefit of small machines and the inelasticity of production rate to inventory. We also give results on the eigenvalues of a more general fluid model, reversible Markov drift processes.

Type
Research Article
Copyright
Copyright © Applied Probability Trust 1988 

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Footnotes

However, the resulting deterministic models, often described as fluid, are to be distinguished from stochastic fluid models such as the one in this paper.

References

[1] Altiok, T. and Perros, H. G. (1986) Open networks of queues with blocking: split and merge configurations. IIE Trans. 251261.Google Scholar
[2] Anick, D., Mitra, D. and Sondhi, M. M. (1982) Stochastic theory of a data-handling system. Bell System Tech. J. 61, 18711894.Google Scholar
[3] Bellman, R. (1970) Introduction to Matrix Analysis, 2nd edn. McGraw-Hill, New York.Google Scholar
[4] Berman, A. and Plemmons, R. J. (1979) Non-negative Matrices in the Mathematical Sciences. Academic Press, New York.Google Scholar
[5] Buzacott, J. A. and Hanifin, L. E. (1978) Models of automatic transfer lines with inventory banks: a review and comparison. AIIE Trans. 10, 197201.CrossRefGoogle Scholar
[6] Choong, Y. F. and Gershwin, S. B. (1985) A decomposition method for the approximate evaluation of capacitated transfer line with unreliable machines and random processing times. MIT Report.Google Scholar
[7] Coderch, M., Willsky, A. S., Sastry, S. S. and Castanon, D. A. (1983) Hierarchical aggregation of singularly perturbed finite state Markov processes. Stochastics 8, 259289.CrossRefGoogle Scholar
[8] Cohen, J. W. (1974) Superimposed renewal processes and storage with gradual input. Stoch. Proc. Appl. 2, 3158.CrossRefGoogle Scholar
[9] Courtois, P. J. (1977) Decomposability: Queueing and Computer System Applications. Academic Press, New York.Google Scholar
[10] Delebecque, F. (1983) A reduction process for perturbed Markov chains. SIAM J. Appl. Math. 43, 325350.CrossRefGoogle Scholar
[11] Gaver, D. P. and Lehoczky, J. P. (1982) Channels that cooperatively service a data stream and voice messages. IEEE Trans. Comm. 30, 11531162.Google Scholar
[12] Gershwin, S. B. and Berman, O. (1981) Analysis of transfer lines consisting of two reliable machines with random processing times and finite storage buffers. AIIE Trans. 13, 211.Google Scholar
[13] Halfin, S. (1972) Steady-state distribution for the buffer content of an M/G/1 queue with varying service rate. SIAM. J. Appl. Math. 23, 369379.CrossRefGoogle Scholar
[14] Halfin, S. (1984) The backlog of data in buffers with variable input and output rates. In Performance of Computer-Communication Systems, ed. Rudin, H. and Bux, W., Elsevier, Amsterdam, 307319.Google Scholar
[15] Halfin, S. and Segal, M. (1972) A priority queueing model for a mixture of two types of customers. SIAM J. Appl. Math. 23, 369379.CrossRefGoogle Scholar
[16] Iyer, B. R. and Mitra, D. (1982) An integrated data-voice system with data buffering and voice blocking. Bell Laboratories Memorandum (available on request).Google Scholar
[17] Karlin, S. and Mcgregor, J. (1965) Ehrenfest urn models. J. Appl. Prob. 2, 352376.Google Scholar
[18] Keilson, J. (1979) Markov Chain Models—Rarity and Exponentiality. Springer-Verlag, New York.CrossRefGoogle Scholar
[19] Kelly, F. P. (1980) Reversibility and Stochastic Networks. Wiley, New York.Google Scholar
[20] Konheim, A. G. and Reiser, M. (1976) A queueing model with finite waiting room and blocking. J. Assoc. Comput. Mach. 23, 328341.Google Scholar
[21] Konheim, A. G. and Reiser, M. (1986) The moveable-boundary multiplexor—stability and decomposability. In Teletraffic Analysis and Computer Performance Evaluation, ed. Boxma, O. J., Cohen, J. W. and Tijms, H. C., North-Holland, Amsterdam, 375394.Google Scholar
[22] Kosten, L. (1974) Stochastic theory of a multi-entry buffer. Delft Progress Report pp. 1018, 44–50, 103–115.Google Scholar
[23] Kosten, L. (1984) Stochastic theory of data-handling systems with groups of multiple sources. In Performance of Computer-Communication Systems, ed. Rudin, H. and Bux, W., Elsevier, Amsterdam, 321331.Google Scholar
[24] Kosten, L. (1986) Liquid models for a type of information storage problems. Delft Progress Report 11, 7186.Google Scholar
[25] Kurtz, T. G. (1978) Strong approximation theorems for density dependent Markov chains. Stoch. Proc. Appl. 6, 223240.Google Scholar
[26] Latouche, G. and Neuts, M. F. (1980) Efficient algorithmic solutions to exponential tandem queues with blocking. SIAM J. Algebra Discrete Meth. 1, 93106.CrossRefGoogle Scholar
[27] Mckenna, J. and Mitra, D. (1988) The transient behaviour of a stochastic data-handling system with multiple sources. In preparation.Google Scholar
[28] Mitra, D. (1988) Optimal allocation of storage space to failure-susceptible machines in a production line. In preparation.Google Scholar
[29] Muth, E. J. (1979) The reversibility properties of production lines. Management Sci. 25, 155169.Google Scholar
[30] Neuts, M. F. (1981) Matrix Geometric Solutions in Stochastic Models. Johns Hopkins University Press, Baltimore.Google Scholar
[31] Pease, M. C. Iii (1965) Methods of Matrix Algebra. Academic Press, New York.Google Scholar
[32] Sevastyanov, B. A. (1962) Influence of storage bin capacity on the average standstill time of a production line. Theory Prob. Appl. 7, 429438.CrossRefGoogle Scholar
[33] Sonneveld, P. (1988) Some properties of the generalized eigenvalue problem Mx = ? (G – cI)x, where M is the infinitesimal generator of a Markov process and G is a real diagonal matrix. Delft Progress Report.Google Scholar
[34] Szego, G. (1939) Orthogonal Polynomials. American Mathematical Society Colloquium Publication 23.Google Scholar
[35] Weiss, A. (1986) A new technique for analyzing large traffic systems. Adv. Appl. Prob. 18, 506532.CrossRefGoogle Scholar
[36] Wijngaard, J. (1979) The effect of interstage buffer storage on the output of two unreliable production units in series, with different production rates. AIIE Trans. 11, 4247.CrossRefGoogle Scholar
[37] Wong, B., Giffin, W. and Disney, R. L. (1977) Two finite M/M/1 queues in tandem: a matrix solution for the steady state . Opsearch 14, 118.Google Scholar