Internet usage has been integrated into most of our activities because of the convenience and accessibility it offers. Arguably, the most common holiday-related online activity users engage in is shopping. Each year, online shoppers troop online to search for the latest promos, coolest gifts, and biggest bargains or to book flights and reservations to go on their dream vacations during the Chri...

OBJECTIVE When someone plans a vacation, one of the last things taken into consideration is the possibility of contracting an illness while away. Unfortunately, if people develop abdominal pain while planning for a vacation, they usually proceed with the vacation and do not consider getting medical attention for their pain. The purpose of this study was to examine the effect of being on vacatio...

We study an M/G/1 queueing system where the arrival follows Poisson Process. The server provides service in two stages, the first stage service is essential and the second stage of service is optional. If the system is empty then the server goes for a vacation of random duration and after returning from vacation the server decides to take a second vacation which is optional. When the server is ...

We consider an M/G/1 quening system, where batches of customers are assumed to arrive the system according to a compound Poisson process. As soon as the system becomes empty, the server takes a vacation for a random length of time called vacation time to do other jobs, which is uninterruptible. After returning from that vacation, there are two possibilities viz. (i) he keeps on taking vacations...

As a generalization of classic queueing models with vacations,the working vacation queues were introduced in 2002, where the server serves customers at a lower rate rather than completely stopping service during the vacation period. This type of vacation models can be applied in performance evaluation of optical communication networks, production and service systems, and other fields. In recent...

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,...