摘要:

AbstractIn this article an interactive method is developed to identify and rank a most preferred subset,T, of alternatives assuming that the decision maker has an implicit quasiconcave nondecreasing utility function. The method requires the decision maker to compare pairs of selected alternatives. Based on the responses of the decision maker, convex cones are constructed to eliminate alternatives that are proved to be inferior to alternatives in setT. The method aims at keeping the number of pairwise comparisons small. Computational experience with the method indicates that the required number of pairwise comparisons to form setTis usually small. However, the number of pairwise comparisons needed to confirm that this set is best may be large.

ISSN:0894-069X    

DOI:10.1002/1520-6750(198908)36:4<359::AID-NAV3220360402>3.0.CO;2-9

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractMathematical models are proposed for studying the impact of miscalibration upon operational effectiveness. Methodology for assessing the system effectiveness and an approach for optimizing the effectiveness of a calibration program are examined. The theory application is discussed and the results of some specific and convenient models are presented.

ISSN:0894-069X    

DOI:10.1002/1520-6750(198908)36:4<373::AID-NAV3220360403>3.0.CO;2-6

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

ISSN:0894-069X    

DOI:10.1002/1520-6750(198908)36:4<383::AID-NAV3220360404>3.0.CO;2-0

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractAn algorithm for constructing a three‐subinterval approximation for any continous distribution function is presented in which the Chebyshev criterion is used, or equivalently, the maximum absolute error (MAE) is minimized. The resulting approximation of this algorithm for the standard normal distribution function provides a guideline for constructing the simple approximation formulas proposed by Shah [13]. Furthermore, the above algorithm is extended to more accurate computer applications, by constructing a four‐polynomial approximation for a distribution function. The resulting approximation for the standard normal distribution function is at least as accurate as, faster, and more efficient than the six‐polynomial approximation proposed by Milton and Hotchkiss [11]and modified by Milton

ISSN:0894-069X    

DOI:10.1002/1520-6750(198908)36:4<389::AID-NAV3220360405>3.0.CO;2-S

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractWe study the problem of finding the minimum number of identical storage areas required to holdnitems for which demand is known and constant. The replenishments of the items within a single storage area may be time phased so as to minimize the maximum total storage capacity required at any time. This is theinventory‐packing problem, which can be considered as a variant of the well‐known bin‐packing problem, where one constraint is nonlinear. We study the worst‐case performance of six heuristics used for that earlier problem since the recognition version of the inventory‐packing problem is shown to be NP complete. In addition, we describe several new heuristics developed specifically for the inventory‐packing problem, and also study their worst‐case performance. Any heuristic which only opens a bin when an item will not fit inany(respectively,the last) open bin needs, asymptotically, no more than 25/12 (resp., 9/4) times the optimal number of bins. Improved performance bounds are obtainable if the range from which item sizes are taken is known to be restricted. Extensive computational testing indicates that the solutions delivered by these heuristics are, for most problems, very close to opt

ISSN:0894-069X    

DOI:10.1002/1520-6750(198908)36:4<399::AID-NAV3220360406>3.0.CO;2-M

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractA survey of the research done on preventive maintenance is presented. The scope of the present survey is on the research published after the 1976 paper by Pierskalla and Voelker [98]. This article includes optimization models for repair, replacement, and inspection of systems subject to stochastic deterioration. A classification scheme is used that categorizes recent research into inspection models, minimal repair models, shock models, or miscellaneous replacement models.

ISSN:0894-069X    

DOI:10.1002/1520-6750(198908)36:4<419::AID-NAV3220360407>3.0.CO;2-5

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractThe purpose of this article is to examine the robustness of the modified Beta distribution as a probability distribution of lot fraction defectives in Bayesian acceptance sampling for statistical quality control. In complex manufacturing systems, a production process may consist of multiple production stages in a serial or nonserial fashion. Hence, inputs to a production station can be a result of subassembly of several inputs, or outputs of some inspection stations for some prior work stages. We investigate the effectiveness of the modified Beta distribution as an approximation to the lot fraction defectives probability of inputs at intermediate work stations. The robustness of the modified Beta distribution simplifies both the determination of the optimal sampling plan for acceptance sampling, and the calibration of distributions resulted from subassembly or inspection operations in complex manufacturing systems.

ISSN:0894-069X    

DOI:10.1002/1520-6750(198908)36:4<447::AID-NAV3220360408>3.0.CO;2-W

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractThe exact first four moments of lead‐time demandLare derived for an AR(1) and a MA(1) demand structures where the arbitrary lead‐time distribution is assumed to be independent of the demand structure. These moments then form a basis for the Pearson curve‐fitting procedure for estimating the distribution ofL. A normal approximation toL, a version of the central limit theorem, is obtained under some general conditions. Reorder points (ROPs) of an inventory system are then estimated based on the Pearson system and a normal approximation. Their performances are evaluated. Numerical investigation shows that the Pearson system performs extremely well. The normal approximation, however, is good only for some limited cases, and is sensitive to the choice of the lead‐time distribution. A possible improvement i

ISSN:0894-069X    

DOI:10.1002/1520-6750(198908)36:4<463::AID-NAV3220360409>3.0.CO;2-R

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractThe article considers a two‐person zero‐sum game in which a searcher withbbombs wishes to destroy a mobile hider. The players are restricted to move on a straight line with maximum speedsvandusatisfyingv>u>0; neither player can see the other but each knows the other's initial position. The bombs all have destructive radiusRand there is a time lagTbetween the release of a bomb and the bomb exploding. The searcher gets 1 unit if the hider is destroyed and 0 if he survives. A solution is given forb= 1, and extended tob>1 when the time lag is small. Various applications of the game are discus

ISSN:0894-069X    

DOI:10.1002/1520-6750(198908)36:4<479::AID-NAV3220360410>3.0.CO;2-7

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractWhile the traditional solution to the problem of meeting stochastically variable demands for inventory during procurement lead time is through the use of some level of safety stock, several authors have suggested that a decision be made to employ some form of rationing so as to protect certain classes of demands against stockout by restricting issues to other classes. Nahmias and Demmy [10] derived an approximate continuous review model of systems with two demand classes which would permit an inventory manager to calculate the expected fill rates per order cycle for high‐priority, low‐priority, and total system demands for a variety of parameters. The manager would then choose the rationing policy that most closely approximated his fill‐rate objectives. This article describes a periodic review model that permits the manager to establish a discrete time rationing policy during lead time by prescribing a desired service level for high‐priority demands. The reserve levels necessary to meet this level of service can then be calculated based upon the assumed probability distributions of high‐ and low‐priority demands over lead time. The derived reserve levels vary with the amount of lead time remaining. Simulation tests of the model indicate they are more effective than the single reserve level policy studied by Nahmia

ISSN:0894-069X    

DOI:10.1002/1520-6750(198908)36:4<491::AID-NAV3220360411>3.0.CO;2-6

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY