A retrial queueing system with a variable number of active servers: Dynamic manpower planning in a call center

Rein Nobel*

*Corresponding author for this work

    Research output: Chapter in Book / Report / Conference proceedingConference contributionAcademicpeer-review

    Abstract

    A retrial queueing model is considered with Poisson input and an unlimited number of servers. At any epoch only a finite number of the servers are active, the others are called dormant. An active server is always in one of two possible states, idle or busy. When upon arrival of a customer at least one of the active servers is idle, the newly arrived customer goes into service immediately, making the idle server busy. When at an arrival epoch all active servers are busy, the decision must be made to send the newly arrived customer into orbit, or to activate a dormant server for immediate service of the arrived customer. Customers in orbit try to reenter the system after an exponentially distributed retrial time. At service completion epochs the decision must be made to keep the newly become idle server active, or to make this server dormant. The service times of the customers are independent and have a Coxian-2 distribution. Given specific costs for activating servers, keeping servers active and a holding cost for customers staying in orbit, the problem is when to activate and shut down servers in order to minimize the long-run average cost per unit time. Using Markov decision theory an efficient algorithm is discussed for calculating an optimal policy.

    Original languageEnglish
    Title of host publicationQueueing Theory and Network Applications - 13th International Conference, QTNA 2018, Proceedings
    PublisherSpringer/Verlag
    Pages33-47
    Number of pages15
    ISBN (Electronic)9783319937366
    ISBN (Print)9783319937359
    DOIs
    Publication statusPublished - 2018
    Event13th International Conference on Queueing Theory and Network Applications, QTNA 2018 - Tsukuba, Japan
    Duration: 25 Jul 201827 Jul 2018

    Publication series

    NameLecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
    Volume10932 LNCS
    ISSN (Print)0302-9743
    ISSN (Electronic)1611-3349

    Conference

    Conference13th International Conference on Queueing Theory and Network Applications, QTNA 2018
    CountryJapan
    CityTsukuba
    Period25/07/1827/07/18

    Keywords

    • Fictitious decision epochs
    • Retrial model
    • Semi-markov decision model

    Fingerprint

    Dive into the research topics of 'A retrial queueing system with a variable number of active servers: Dynamic manpower planning in a call center'. Together they form a unique fingerprint.

    Cite this