Hall, Leung & Li have recently proposed a new model for human multitasking behavior. In their model, a primary job gets interruptions from all waiting jobs whenever it is being processed. Every time an interruption has been received, the worker switches from the primary job to the interrupting job. After part of the interrupting job has complete, the worker switches back to the primary job. Her...

In 1] a branch-and-bound implicit enumeration algorithm is described to generate a feasible schedule, if any, for each processor on a multiprocessing node running hard real-time processes. The optimization criterion is to minimize process lateness deened as the diierence between the process completion time and deadline. We show in this correspondence that this algorithm does not always succeed ...

In this paper we present a comparison of the service disciplines in real-time queueing systems (the customers have a deadline before which they should enter the service booth). We state that the more a service discipline gives priority to customers having an early deadline, the least the average stationary lateness is. We show this result by comparing adequate random vectors with the Schur-Conv...

We consider the problem of common due-date to of simultaneously available jobs and sequencing them on a that a number of the jobs are tardy. The optimal combination of the common due-date and job sequence that minimizes the total absolute lateness. A simple to achieve this. Effectively three independent procedures : one to the nnT,nn<>1 sequence; a second to the optimal due date and a third to ...

In this paper optimal outpatient appointment scheduling is studied. A local search procedure is derived that converges to the optimal schedule with a weighted average of expected waiting times of patients, idle time of the doctor and tardiness (lateness) as objective. No-shows are allowed to happen. For certain combinations of parameters the well-known Bailey-Welch rule is found to be the optim...

Vietnam was previously lauded as a model for fighting the COVID-19 pandemic and it imposed localized lockdowns to deal with emergence of deadly new variants. Here, daily data from 63 Vietnamese provinces period January–July 2021 (i.e., before vaccinations became available) are collected, panel event study is performed evaluate effectiveness lockdown policy. The number infected cases found incre...

One machine scheduling problem with fuzzy processing times and a penalty for each job being late (the penalty is independent of the magnitude of the lateness) is considered. The optimal sequence is defined as one minimizing the expected value of the total penalty (the expected weighted number of jobs being late). Two special cases are discussed in which the problem can be reduced to well-known ...