日本オペレーションズ・リサーチ学会論文誌
Online ISSN : 2188-8299
Print ISSN : 0453-4514
ISSN-L : 0453-4514
41 巻, 3 号
選択された号の論文の17件中1~17を表示しています
  • 原稿種別: 表紙
    1998 年 41 巻 3 号 p. Cover7-
    発行日: 1998年
    公開日: 2017/06/27
    ジャーナル フリー
  • 原稿種別: 付録等
    1998 年 41 巻 3 号 p. App5-
    発行日: 1998年
    公開日: 2017/06/27
    ジャーナル フリー
  • 松本 輝夫, 土屋 昇, 澄川 順二, 仁尾 都
    原稿種別: 本文
    1998 年 41 巻 3 号 p. 333-350
    発行日: 1998年
    公開日: 2017/06/27
    ジャーナル フリー
    本論文ではプラント配管の溶接費用を最小にするような最適溶接位置決定問題への動的計画法の適用について述べる. 配管はエルボやT継ぎ手, 素材管を組立溶接して作られる. 搬送可能な大きさに分割されたスプールと呼ぶ部分配管を工場溶接で製作し, 現地で配管全体を組み立て現地溶接している. ここで考慮した条件は工場溶接及び現地溶接の単価, 輸送限界で制限されたスプールの大きさ, 配管中で溶接できない溶接禁止領域や, 溶接しなければならない溶接必要領域, 素材管の長さの制約である. 溶接費用が最小となる関数を以下に示す. [numerical formula] [numerical formula] ここで, x, y, tは配管上の位置を表し, 配管の中心線をメッシュに分割した時のメッシュの境界に始点側から付けた番号である. 始点の番号を0, 終点の番号をmとする. Y(x)は, yからxまでが一つの輸送可能なスプールとなりうるスプールの開始位置yの集合で, W(y,x)は, yとxの間にあってyに最も近い工場溶接となりうる位置tの集合である. F(x)は始点からxまでの現地溶接費用と工場溶接費用の和の最小値であり, G(y,x)は, yからxまでのスプール内にある工場溶接費用の最小値である. C1とC2はそれぞれ現地溶接と工場溶接の単価である. 最後に, 提案した方法による溶接費用の計算結果は従来の手法に比較して10%少ない値を示し, 人手による作業時間の20%の工数で溶接位置を計算出来ている.
  • Toshiharu Fujita, Kazuyoshi Tsurusaki
    原稿種別: Article
    1998 年 41 巻 3 号 p. 351-373
    発行日: 1998年
    公開日: 2017/06/27
    ジャーナル フリー
    In this paper we show three methods for solving optimization problems of expected value of multiplicative functions with negative values; multi-stage stochastic decision tree, Markov bidecision process and invariant imbedding approach.
  • Ryusuke Hohzaki, Koji Iida, Masaki Kiyama
    原稿種別: Article
    1998 年 41 巻 3 号 p. 374-386
    発行日: 1998年
    公開日: 2017/06/27
    ジャーナル フリー
    This paper investigates the search problem for a moving target when a search path is given in advance. The searcher's strategy is represented by a randomized look strategy, that is, the probability with which he looks in his current position at each discrete time. The searcher knows the probabilistic law about which one of some options the target selects as his path. If the detection of the target occurs by the looking, the searcher gains some value but must expend some cost for the looking. The searcher wants to determine his optimal look strategy in order to maximize the expected reward which is defined as the expected value minus the expected cost. He can randomize his look strategy by the probability that he looks in his current position. We prove the NP-completeness of this problem and propose a dynamic programming method to give an optimal solution which becomes the bang-bang control in the result. We derive some characteristics of the optimal look strategy and analyze them by some numerical examples.
  • Akira Tajima, Syoiti Ninomiya, Shu Tezuka
    原稿種別: Article
    1998 年 41 巻 3 号 p. 387-397
    発行日: 1998年
    公開日: 2017/06/27
    ジャーナル フリー
    Recently, Paskov reported that the use of a certain pseudo-random number generator, ran1(), given in Numerical Recipes in C, First Edition makes Monte Carlo simulations for pricing financial derivatives converge to wrong values. In this paper, we trace Paskov's experiment, investigate the characteristics and the generation algorithm of the pseudo-random number generator in question, and explain why the wrong convergences occur. We then present a method for avoiding such wrong convergences. A variance reduction procedure is applied, together with a method for obtaining more precise values, and its correctness is examined. We also investigate whether statistical tests for pseudo-random numbers can detect the cause of wrong convergences.
  • Bao-Lin Guo, Yoshitsugu Yamamoto
    原稿種別: Article
    1998 年 41 巻 3 号 p. 398-403
    発行日: 1998年
    公開日: 2017/06/27
    ジャーナル フリー
    By developing an algorithm, Herings, Talman and Yang [6] recently proved the following interesting and deep theorem: A correspondence ζ from the n-dimensional unit cube U^n to the n-dimensional Euclidean space R^n has a continuum of zero points containing the origin and the vector of all-ones if the correspondence satisfies certain conditions. In this note we give an alternative proof of the theorem in the case where the correspondence ζ: U^n → R^n is single-valued.
  • Shunsuke Shiraishi, Tsuneshi Obata, Motomasa Daigo
    原稿種別: Article
    1998 年 41 巻 3 号 p. 404-414
    発行日: 1998年
    公開日: 2017/06/27
    ジャーナル フリー
    The characteristic polynomial of a positive reciprocal matrix has some noteworthy properties. They are deeply related to the notion of consistency of a pairwise comparison matrix of AHP. Based on the results, we propose a method for estimating a missing entry of an incomplete pairwise comparison matrix.
  • Nobuko Igaki, Ushio Sumita, Masashi Kowada
    原稿種別: Article
    1998 年 41 巻 3 号 p. 415-429
    発行日: 1998年
    公開日: 2017/06/27
    ジャーナル フリー
    A generalized M/G/1 queueing system is considered where the efficiency of the server varies as the number of customers served in a busy period increases due to server fatigue or service enforcement. More specifically, the k-th arriving customer within a busy period has the random service requirement V_k where the 0-th customer initiates the busy period and V_k (k = 0,1,2,・・・) are mutually independent but may have different distributions. This model includes an M/G/1 queueing model with delayed busy period as a special case where V_k are i.i.d. for k ≥ 1. Transform results are obtained for the system idle probability at time t, the busy period, and the number of customers at time t given that m customers have left the system at time t since the commencement of the current busy period. The virtual waiting time at time t is also analyzed. A special case that V_k are i.i.d. for k ≥ 2 is treated in detail, yielding simple and explicit solutions.
  • Andreas Frey, Yoshitaka Takahashi
    原稿種別: Article
    1998 年 41 巻 3 号 p. 430-441
    発行日: 1998年
    公開日: 2017/06/27
    ジャーナル フリー
    We consider an M/GI/1/N queue with vacation time and exhaustive service discipline. We show that the embedded Markov chain formed by the customer departure epochs makes the analysis simple and it enables us to find an explicit solution for the server-vacation queue. We also find an explicit solution for the ordinary (non-vacation) queue.
  • Shigemichi Suzuki, Hideaki Yamashita
    原稿種別: Article
    1998 年 41 巻 3 号 p. 442-454
    発行日: 1998年
    公開日: 2017/06/27
    ジャーナル フリー
    We analyze alternating traffic crossing a narrow one-lane bridge on a two-lane road. Once a car begins to cross the bridge in one direction, arriving cars from the other direction must wait, forming a queue, until all the arrivals in the first direction finish crossing the bridge. Such a situation can often be observed when road-maintenance work is carried out. Cars are assumed to arrive at the queues according to independent Poisson processes and to cross the bridge in a constant time. In addition, once cars join the queue, each car needs a starting delay, a constant, to start crossing the bridge. We model the situation where a signal controls the traffic so that the signal gives a priority to one direction at least for a fixed time. Under an assumption, the first two moments of a period during which the signal keeps giving a priority to one direction are obtained. Using a stochastic decomposition property the mean waiting times are obtained of cars to start crossing the bridge from each direction.
  • 小宮 享, 森 雅夫
    原稿種別: 本文
    1998 年 41 巻 3 号 p. 455-469
    発行日: 1998年
    公開日: 2017/06/27
    ジャーナル フリー
    日本周辺海域においては, 一般船舶の航路保全・不審船舶の早期発見/対処を目的とする, 航空機による海上監視活動が定期的に実施されている. この際の基準となる飛行経路の設定に関し, 季節的に変動する漁船位置情報や将来位置が予測される船舶の分布に関する情報等が考慮されてこなかった. 本研究では, これらの情報を考慮に入れた, 限られた飛行時間内での効率的な飛行基準経路を設定する方法を提案し, モデル例によりその妥当性を検証した. この方法により, 船舶の将来位置からの逸脱が少ない基準経路の設定が可能となる.
  • Ryusuke Hohzaki, Koji Iida
    原稿種別: Article
    1998 年 41 巻 3 号 p. 470-482
    発行日: 1998年
    公開日: 2017/06/27
    ジャーナル フリー
    This paper investigates a non-linear integer programming problem with an exponential objective function and cost constraints, which is a general model and could be applied to the assignment problem or the search problem. As a representative example, we consider a following problem of assigning m types of missiles to n targets. The value of target i is V_i and the single shot kill probability (SSKP) of a j-type missile to target i is β_<ij> = 1 - exp(-α_<ij>) where α_<ij> &ge; 0. Denoting the number of j-type missiles assigned to target i by n_<ij>, the expected destroyed value is given by Σ^n_<i=1>V_i{1 - exp(-Σ_jα_<ij>n_<ij>)}. If a unit price of j-type missile is c_j and the total cost of missiles is limited by C, we have cost constraints Σ^m_<j=1>c_jΣ^n_<i=1>n_<ij>&le;C. To this problem which is NP-hard, we propose two methods, the dynamic programming method and the branch and bound method. An approximate algorithm and an estimation of the upper bound of the objective function are incorporated in the branch and bound method. Each of these methods has its characteristic merits for the computational time. We clarify their characteristics through the sensitivity analysis by some examples in this paper.
  • 原稿種別: 付録等
    1998 年 41 巻 3 号 p. 483-486
    発行日: 1998年
    公開日: 2017/06/27
    ジャーナル フリー
  • 原稿種別: 付録等
    1998 年 41 巻 3 号 p. 487-
    発行日: 1998年
    公開日: 2017/06/27
    ジャーナル フリー
  • 原稿種別: 表紙
    1998 年 41 巻 3 号 p. Cover8-
    発行日: 1998年
    公開日: 2017/06/27
    ジャーナル フリー
  • 原稿種別: 表紙
    1998 年 41 巻 3 号 p. Cover9-
    発行日: 1998年
    公開日: 2017/06/27
    ジャーナル フリー
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