The preconditioned conjugate gradient method is employed to solve Toeplitz systems T n x = b where the generating functions of the n-by-n Toeplitz matrices T n are functions with zeros. In this case, circulant preconditioners are known to give poor convergence, whereas band-Toeplitz preconditioners only ooer linear convergence and can only handle real-valued functions with zeros of even orders....

In this paper a single server preemptive priority queuing system consisting of two types of customer units with Poisson arrival, exponential service time distribution and exponential vacation is analyzed. Two type of customer units of which higher priority units of unlimited Poisson input are served by bulk service rule and limited Poisson input of low priority units served singly. The bulk ser...

We consider a dispatching system, where jobs, arriving in batches, are assigned to single-server FCFS queues. Batches can be split to different queues on per job basis. However, the holding costs are batch-specific and incurred until the last member of the batch completes the service. By using the first policy improvement step of the MDP framework, we are able to derive robust dispatching polic...

We study the decisions agents make in two queueing games with endogenously determined arrivals and batch service. In both games, agents are asked to independently decide when to join a queue, or they may simply choose not to join it at all. The symmetric mixed-strategy equilibrium of two games in discrete time where balking is prohibited and where it is allowed are tested experimentally in a st...

We study multi-product and multi-item assemble-to-order systems under general assumptions on demand patterns and replenish leadtime distributions. We only assume that the demand process of each product being a renewal process, and the replenish leadtimes follow general distributions. Based upon techniques from renewal theory, we developed procedures for approximating key performance measures of...

front of the batch processor, where they wait to be processed. The batch processor has a finite capacity Q, and the processing time is independent of the number of jobs loaded into the batch processor. In certain manufacturing systems (including semiconductor wafer fabrication), a processing time window exists from the time the job exits the feeder processor till the time it enters the batch pr...

New Broadband Communication Networks are playing a key role in providing a variety of multimedia services such as voice, video and data etc. The amount of information per unit time generated by these services varies along the connection duration. There are certain periods in which the information rate increases and others in which it decreases or becomes null. As the sources providing such serv...

Many research works in mathematical modeling of the facility location problem have been carried out in discrete and continuous optimization area to obtain the optimum number of required facilities along with the relevant allocation processes. This paper proposes a new multiobjective facility-location problem within the batch arrival queuing framework. Three objective functions are considered: (...

We consider a queueing system consisting of multiple identical servers and a common queue. The service time follows an exponential distribution and the arrival process is governed by a semi-Markov process (SMP). The motivation to study the queueing system with SMP arrivals lies in that it can model the auto-correlated traffic on the high speed network generated by a real time communication, for...