This report presents a new analytic method for checking the Schur stability of interval polynomial matrix (polynomials whose coefficients are interval matrices). In the suggested method, the interval Markov matrices of the interval polynomial matrix are used to assess its stability. The validity of the suggested method is illustrated through numerical examples. The proposed technique is algebra...

We consider a retrial queue with a finite buffer of size N , with arrivals of ordinary units and of negative units (which cancel one ordinary unit), both assumed to be Markovian arrival processes. The service requirements are of phase type. In addition, a PH bulk service discipline is assumed. This means that the units are served in groups of size at least L, where 1 ≤ L ≤ N . If at the complet...

Mean value analysis is an elegant tool for determining mean performance measures in queueing models. We use the technique to analyze the M/G/1 retrial queue with exponential retrial times. We also show how the relations can be adapted to obtain mean performance measures in more advanced M/G/1-type retrial queues.

In this paper, we consider retrial queueing systems with batch arrivals in which the server is subject to controllable interruptions (called vacations) and random interruptions (breakdowns). No specific assumption is taken regarding probability distributions of parametric random variables. The purpose of this work is to show effect of above mentioned parameters (in particular retrial and breakd...

determining production rate considering costs and revenues in order to maximize profit is one of the applied problems in small and medium size factories. mostly existing models in production planning consider production system statically and specify production rate, although the factors determining production rate include many different changes in practice. in fact, by increasing the production...

Production costs in general, and workforce and inventory costs in particular, constitute a large fraction of the operating costs of many manufacturing plants. We introduce cooperative aggregate production planning as a way to decrease these costs. That is, when production planning of two or more facilities (plants) is integrated, they can interchange workforce and products inventory; thus, thei...

Abstract: We consider a discrete-time 1 X Geo G retrial queue with general retrial times, and introduce working vacations and vacation interruption policy into the retrial queue. Firstly, we analyze the stationary condition for the embedded Markov chain at the departure epochs. Secondly, using supplementary variable method, we obtain the stationary probability distribution and some performance ...

This paper proposes an analytical method for performance evaluation and optimization of a production-distribution system composed of a warehouse supplied from an upstream manufacturing plant. Customer orders arrive randomly with random order size and the production capacity is finite. Transportation time from plant to warehouse is fixed. The analytical approach needs only the first two moments ...

W study inventory pooling in systems with symmetric costs where supply lead times are endogenously generated by a finite-capacity production system. We investigate the sensitivity of the cost advantage of inventory pooling to various system parameters, including loading, service levels, demand and production time variability, and structure of the production system. The analysis reveals differen...

Bottleneck appears in a serial supply chain if the minimum production rate at all stages is smaller than the demand rate. Operation manager must focus on keeping the bottleneck stage fully utilized and forcing the other stages to produce in synch with the bottleneck. This study applies the lot size division method, the recursive tightening method, and the drum-buffer-rope strategy. A pull and r...