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 deals with finite capacity single server queuing system with vacations. Vacation starts at rate nu if the system is empty. Also the server takes another vacation if upon his arrival to the system, finds the system empty. Customers arrive in the system in Poisson fashion at rate lamda0 during vacation, faster rate lamdaf during active service and slower rate lamdas during the breakdow...

This paper investigates an M [x] /G/1 queueing system with an unreliable server, where the server may take an additional vacation after the essential vacation. If the system becomes empty, the server leaves the system and takes the essential vacation. At the end of the essential vacation, the server may return to the system with probability p or take another vacation with probability 1-p. When ...

We consider a queueing system with c servers and a threshold type vacation policy. In this system, when a certain number d<c of servers become idle at a service completion instant, these d servers will take a synchronous vacation of random length together. After each vacation, the number of customers in the system is checked. If that number is N or more, these d servers will resume serving the ...

We have been successfully deploying mobile service robots in an office building to execute user-requested tasks, such as delivering messages, transporting items, escorting people, and enabling telepresence. Users submit task requests to a dedicated website which forms a schedule of tasks for the robots to execute. The robots autonmously navigate in the building to complete their tasks. However,...

In this paper, a multi phase M/G/1queueing system with Bernoulli feedback where the server takes multiple vacation is considered. All the poisson arrivals with mean arrival rate will demand any of the multi essential services.. The service times of the first essential service are assumed to follow a general distribution Bi(v). After the completion of any of the n services, if the customer is di...

We have been successfully deploying mobile service robots in an office building to execute user-requested tasks, such as delivering messages, transporting items, escorting people, and enabling telepresence. Users submit task requests to a dedicated website which forms a schedule of tasks for the robots to execute. The robots autonomously navigate in the building to complete their tasks. However...

A specific characteristic of sensor network applications is that the major traffic consists of data collection from various sensor source nodes to a sink via a unidirectional tree. In this paper, we propose DMAC, an energy efficient and low latency MAC that is designed and optimized for such data gathering trees in wireless sensor networks. We first show that previously proposed MAC protocols f...