1,720,971 research outputs found
A mean-value approach for M/G/1 priority queues
No full textThis note deals with a mean-value approach for M/G/1 priority queues. Using the residual life-time formula, Little's formula and the fact that Poisson arrivals see time averages, we derive schemes to evaluate mean response times, mean queue lengths and mean waiting times for the respective priority classes
A note on RECAL : the recursion by chain algorithm
No full textThis note considers an alternative derivation of the basic recursive relation in the recently developed RECAL or recursion by chain algorithm for the evaluation of the normalization constant of a product-form closed multichain queueing network model. The technique is based on a z-transform representation of the set of normalization constants
A mean value analysis of a closed CP-terminal system with pre-emptive resume priorities and general service time distributions
No full textThis paper deals with the analysis of a queueing system which may be used as a model for a computer system with terminals, the so-called CP-terminal system, or a machine-interference model. The system can be viewed as a single server queue with a number of finite Poisson sources, general service time distributions and a preemptive resume priority scheduling. A recursive scheme will be derived for the computation of performance measures. The technique is based on mean value ideas and renewal arguments
The design of a system with two parallel queues and one-way overflow
No full textThis paper deals with the problem how to design a queueing system, where two independent Poisson arrival streams have to be served efficaciously. The system consists of two parallel multiserver queues with waiting-rooms in which one-way overlow is allowed for.
First a concise analysis for both exact and approximative methods in the system with over low is given. Then we show that in a specific situation a conversational computer algorithm might be an efficient instrument in the design of such systems. Special attention is devoted to a particular step in the algorithm: the solution of an optimization problem. An enumeration algorithm, using the proposed approximations, is discussed.
Eventually some conclusions are drawn
An iterative approximation for closed queueing networks with two-phase servers
No full textThis paper deals with an iterative method to obtain approximations for mean values in closed queueing networks with two-phase servers. The servers are particular in a sense that the first phase, a preparatory one, can be done while no customers are at the server
On two parallel queues with one-way overflow
No full textThis paper deals with a system consisting of two parallel multiserver queues with waiting places, which receive demands from two types of customers respectively. Customers for the first queue are allowed to overflow to the second queue, if they are blocked at the first queue.
The first sections of the paper are devoted to the numerical solution of the linear system of equilibrium equations in order to be able to compute loss probabilities and average system times. The algebraic structure of the linear system leads naturally to the use of a block iterative method. An iteration procedure based on the Accelerated Overrelaxation (AOR) method is described. Then the behaviour of systems with two parallel queues is discussed. Remarks are made with respect to some general notions on how to find queueing systems that satisfy certain requirements
- …
