we propose to use a mathematical method based on stochastic comparisons of markov chains in order to derive performance indice bounds‎. ‎the main goal of this paper is to investigate various monotonicity properties of a single server retrial queue with first-come-first-served (fcfs) orbit and general retrial times using the stochastic ordering techniques‎.

The present investigation deals with the bulk arrival M/G/1 retrial queue with impatient customers and modified vacation policy. The incoming customers join the virtual pool of customers called orbit if they find the server being busy, on vacation or in broken down state otherwise the service of the customer at the head of the batch is started by the server. The service is provided in k</em...

This paper analyzes a renewal input  working vacations queue with change over times and Bernoulli schedulevacation interruption under (a,c,b) policy.The service and vacation times are exponentially distributed.The server begins service if there are at least c units in the queue and the service takes place in batches with a minimum of size a and a maximum of size b (a

we consider an m/g/1 queue with regular and optional phase vacation and withstate dependent arrival rate. the vacation policy is after completion of service if there are no customers in the system, the server takes vacation consisting of k -phases, each phase is generally distributed. here the first phase is compulsory where as the other phases are optional. for this model the supplementary var...

This paper represents linkage network of queues consisting of biserial and parallel servers linked to a common server in series with a flowshop scheduling system consisting of two machines. The significant transportation time of the jobs from one machine to another is also considered. Further, the completion time of jobs/customers (waiting time + service time) in the queue network is the set...

This paper deals with the study of multi-server queueing model in a fuzzy environment imposition reneging customers. Entry customers system is assumed to be Poisson process and exponential service time distribution under first-come-first-served basis. Specific this investigation derive various performance measures such as queue length, waiting queue, response optimal number servers explicit for...

conclusions: the patients' waiting times and the number of patients waiting to receive services in both shifts could be reduced by using multitasking persons and reallocating them to the time-consuming stage of filling prescriptions, using queuing theory and simulation techniques. background: hospital pharmacy is responsible for controlling and monitoring the medication use process and ensures ...