We consider a single server queue in which the arrivals occur according to a Markovian arrival process. The system is subject to external shocks causing the server to deteriorate and possibly fail. The maintenance of the server is provided either as a preventive one or for a complete failure so...

We consider a multi-server queueing model in which the arrivals occur according to a Markovian arrival process. One of the servers, henceforth referred to as the main server, offers consultation to fellow servers (referred to as regular servers) apart from serving the customers. A regular server...