In view of the very complex equipment making up the LHC machine and its many ancillary subsystems, equipment maintenance policies will play a primordial role to ensure an optimal availability. As access to most of the machine systems is strictly regulated, maintenance interventions will require global co-ordination and collaboration from both CERN equipment groups and industrial support teams. ...

In this paper, we propose an N × N high speed and non-blocking asynchronous transfer mode (ATM) switch with input and output buffers. In this switch, each buffer adopts a priority discarding scheme, which discards incoming cells of low-priority traffic when its queue length is greater than a predefined threshold value. Our switch also supports broadcast/multicast functions without increasing th...

The purpose of this paper is two fold. First to establish the Theory of discounted constrained Markov Decision Processes with a countable state and action spaces with general multi-chain structure. Second, to introduce nite approximation methods. We deene the occupation measures and obtain properties of the set of all achievable occupation measures under the diierent admissible policies. We est...

We study tail asymptotics of the stationary distribution for the GI=G=1-type Markov chain with finitely many background states. Decay rate in the logarithmic sense is identified under a number of conditions on the transition probabilities. The results are applied to the BMAP=G=1 queuewith vacations. The relationship between vacation time and the decay rate of the queue length distribution is in...

Clustering parts and machines into part families and machine cells is a major decision in the design of cellular manufacturing systems which is defined as cell formation. This paper presents a non-linear mixed integer programming model to design cellular manufacturing systems which assumes that the arrival rate of parts into cells and machine service rate are stochastic parameters and descri...

We consider a single stock point for a repairable item. The repairable item is a critical component that is used in a fleet of technical systems such as trains, planes or manufacturing equipment. A number of spare repairables is purchased at the same time as the technical systems they support. Demand for those items is a Markov modulated Poisson process of which the underlying Markov process ca...

This paper gives a natural definition of the relaxation time for general single server queues. First, we describe a GI/GI/I queue as a limit of GI/GPH/I queues. Each GI/GPH/I queue is transferred to some equivalent bulk arrival GIx/M/I queue, which is formulated by a spatially homogeneous Markov chain with reflecting barrior at zero. An upper bound, which is easy to calculate, of the relaxation...

This paper deals with a discrete-time bulk-service Geo/Geo/1 queueing system with infinite buffer space and multiple working vacations. Considering an early arrival system, as soon as the server empties the system in a regular busy period, he leaves the system and takes a working vacation for a random duration at time n. The service times both in a working vacation and in a busy period and the ...

Suppose G=(V,A) be an undirected graph with n nodes and a source vertex s Є V. Each node has a problem that must be solved by the repairman that has send. We are given the time required by the repairman to travel among nodes. The objective is to find a tour that minimizes the total waiting time of all the problems that are waiting to be solved. Traveling Repairman problem (TRP) is also known as...

This paper analyses a single server with bulk service queue with general arrival pattern and multiple working vacation period. The model is analyzed by using Embedded Markov Chain technique. The steady state probability distribution at pre arrival epoch and arbitrary epoch are derived and measures like mean queue length are calculated. Finally, through some numerical examples, the parametric ef...