定例部会案内

第277回部会
日時: 平成30年7月28日(土) 14:00〜17:00
場所: 東京工業大学 大岡山キャンパス 西8号館(W)809号室
テーマと講師
  1. Externalities, optimization and regulation in queues
    Moshe Haviv (The Hebrew University of Jerusalem)
    The academic research on queues deals mostly with waiting. Yet, the externalities, namely the added waiting time an arrival inflicts on others, are of no less, if not of more, importance. The talk will deal mostly with how the analysis of externalities leads to the socially optimal behavior, while solving queueing dilemmas such as whether or not to join a queue, when to arrive to a queue, or from which server to seek service at. Customers, being selfish, do not mind the externalities they impose on others. We show how in queues too, internalizing the externalities leads to self regulation. In this setting selecting the service regime is one of the tools in one's arsenal. (Joint with Binyamin Oz)
  2. Getting More Out of Generating Functions than Just Mean Values
    Joris Walraevens (Ghent University)
    Many queueing systems can be solved through transform functions. The probability generating function (PGF) of the stationary buffer occupancy in the M/G/1 queue for instance is given by the celebrated Pollaczek-Khinchine formula. The strength of the transform technique is that explicit results can be found even when this is not possible for the corresponding distributions. However, although all information of this distribution is also present in the transform function, the information that is extracted from this transform does usually not go beyond the mean value (and perhaps the variance). In this presentation, we show how dominant singularity analysis of the PGFs (we concentrate on PGFs, but similar techniques apply for Laplace-Stieltjes transforms) of the (low-priority) customers (in orbit) in the M/G/1 FIFO, M/G/1 priority and M/G/1 retrial queues leads to asymptotics of the corresponding distributions. Distributions for the service times may be light-tailed and/or heavy-tailed. For the M/G/1 FIFO queue, this is not too difficult as the PGF is not very involved. For the M/G/1 priority and retrial queues however, integrals and implicit functions appear in the expressions. We show how we use the work of Flajolet and Sedgewick [1] to deal with those.
    [1] P. Flajolet and R. Sedgewick, Analytic Combinatorics, Cambridge University Press, 2009.

  3. 第6回(2017年度)待ち行列研究部会「論文賞」受賞者

    第6回(2017年度)待ち行列研究部会「論文賞」受賞者は以下の方に決定しました.
    【受賞者および対象論文】
    高木 英明,家内 祐太,三末 和男(筑波大学)
    Queueing network model for obstetric patient flow in a hospital,
    Health Care Management Science, Vol.20, No.3, pp.433-451, 2017.
    詳細はこちらをご確認ください.

    2017年度待ち行列研究部会「研究奨励賞」受賞者

    2017年度待ち行列研究部会「研究奨励賞」受賞者は以下の方々に決定しました.
    【受賞者(敬称略)および対象論文】
    木村 雅俊(大阪大学)
    レベル依存する G/G/1 型マルコフ連鎖における条件付き定常分布の誤差評価付き数値計算法

    矢島 萌子(東京工業大学)
    マルコフ型集団到着過程と裾の軽いサービス分布を持つ無限サーバ待ち行列の安定性の十分条件


    (2018年6月19日更新)