In this paper, we consider a multi-server queuing system in which additional servers are allowed for a longer queue to reduce the customer’s balking and reneging behavior. The customers are assumed to arrive in Poisson fashion and their service- times follow exponential distribution. The number of servers in long run depends on the queue-length. We obtain equilibrium queue size distribution. Th...

modeling and wrench feasible workspace analysis of a spatial cable suspended robots is presented. a six-cable spatial cable robot is used the same as stewart robots. due to slow motion of the robot we suppose the motion as pseudostatic and kinetostatic modeling is performed. various workspaces are defined and the results of simulation are presented on the basis of various workspaces and applied...

Fluid models have for some time been used to approximate stochastic networks with discrete state. These range from traditional ‘heavy traffic’ approximations to the recent advances in bio-chemical system models. Here we present a simple approximate compositional method for analysing a network of fluid queues with Markovmodulated input processes at equilibrium. The idea is to approximate the on/...

It is known that entropy maximised MlGI/l queues yield queue length distributions that are geometric when the constraints involve only the first two moments of the service time distribution. By proving that geometric queue lenth is equivalent to exponential service in MlGIil queues, we show that using the entropy maximisation procedure with only two service time moments is equivalent to using e...

In the author’s recent paper [11], it is established that in a multiclass single-server queue with regular service disciplines, the stationary distributions and their moments for workload as well as for queue length can be approximated by appropriate exponential distributions and their moments in the heavy-traffic regime. In this work, relaxing the assumption of moment generating function on th...

We provide additional descriptions of the steady-state waiting-time distribution in the M/G/1 queue with the last-in firstout (LIFO) service discipline. We establish heavy-traffic limits for both the cumulative distribution function (cdf) and the moments. We develop an approximation for the cdf that is asymptotically correct both as the traffic intensity p ~ 1 for each time t and as t ~ oo for ...

In this paper, we propose an algorithm to calculate the higher moments of the busy period length of a discretetime M/G/1 type queue with finite buffer. The queueing model has a level-dependent transition probability matrix. Our algorithm is given as a set of recursive formulas which are derived from the relationship among the generating function matrices of the fundamental period. As an example...

In this paper we study a single-server queue where the inter-arrival times and the service times depend on a common discrete time Markov Chain. This model generalizes the well-known MAP/G/1 queue by allowing dependencies between interarrival and service times. The waiting time process is directly analyzed by solving Lindley’s equation by transform methods. The Laplace Stieltjes transforms (LST)...

We provide additional descriptions of the steady-state waiting-time distribution in the M/G/1 queue with the last-in first-out (LIFO) service discipline. We establish heavy-traffic limits for both the cumulative distribution function (cdf) and the moments. We develop an approximation for the cdf that is asymptotically correct both as the traffic intensity ρ → 1 for each time t and as t → ∞ for ...