This paper studies the machine repair problem consisting of M operating machines with S spare machines, and R servers (repairmen) who leave for a vacation of random length when there are no failed machines queuing up for repair in the repair facility. At the end of the vacation the servers return to the repair facility and operate one of three vacation policies: single vacation, multiple vacati...

This study adds to research on the beneficial effects of vacation to employees' well-being and on the fade-out of these effects. One hundred and thirty-one teachers completed questionnaires one time before and three times after vacationing. Results indicated that teachers' work engagement significantly increased and teachers' burnout significantly decreased after vacation. However, these benefi...

The underlying structure of why and how consumers value reliability of electric service is explored, together with the technological options and cost characteristics for the provision of reliability and the conditions under which market mechanisms can be used to match these values and costs efficiently. This analysis shows that the level of reliability of electricity provided through a network ...

The underlying structure of why and how consumers value reliability of electric service is explored, together with the technological options and cost characteristics for the provision of reliability and the conditions under which market mechanisms can be used to match these values and costs efficiently. This analysis shows that the level of reliability of electricity provided through a network ...

Virtual health counseling agents on mobile devices need to be able to interrupt their users when it is time for them to engage in healthy behaviors, such as scheduled medication taking or exercise. However, these real-time reminders often represent task interruptions for individuals who are engaged in work activities. This paper presents the results of a study which compares four strategies use...

Recent research has shown that crowd sourcing can be used effectively to solve problems that are difficult for computers, e.g., optical character recognition and identification of the structural configuration of natural proteins. In this paper we propose to use the power of the crowd to address yet another difficult problem that frequently occurs in a daily life answering planning queries whose...

We consider a problem of repeatedly scheduling n jobs on m parallel machines. Each job is associated with a profit, gained each time the job is completed, and the goal is to maximize the average profit per time unit. Unlike other periodic scheduling problems, there is no fairness requirement. Still, it is impossible to process only the most profitable jobs, because once the processing of a job ...

This paper addresses the problem of deciding effectively whether to interrupt a teammate who may have information that is valuable for solving a collaborative scheduling problem. Two characteristics of multi-agent scheduling complicate the determination of the value of the teammate’s information, and hence whether it exceeds the costs of an interruption. First, in many scheduling contexts, task...

Defeasible reasoning is concerned with the logics of non-deductive argument. As is described in the literature, the study of this type of reasoning is considerably more involved than the study of deductive argument, even so that, in realistic applications, there is often a lack of resources to perform an exhaustive analysis. It follows that, in a theory of defeasible reasoning, the order and di...

We adapt the descendant set approach used in polling models to the continuous fluid model. This enables to establish the steady-state relationship on Laplace transform level among the joint distributions of the fluid level and the state of the modulating Markov chain at end of vacation and at start of vacation. The main results of the paper are the steady-state vector LT and mean of the fluid l...