摘要:

AbstractThis paper considers elimination methods in solving the sequencing problem where no passing is permitted. An elimination method consists of reducing (according to some criterion) the initial set of n solutions to a smaller set. A crucial question arises as to whether this reduced set contains an optimal solution. The answer is affirmative if this elimination criterion implies condition (3).

ISSN:0028-1441    

DOI:10.1002/nav.3800180302

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

年代:1971

数据来源: WILEY

摘要:

AbstractFractional fixed‐charge problems arise in numerous applications, where the measure of economic performance is the time rate of earnings or profit (equivalent to an interest rate on capital investment). This paper treats the fractional objective function, after suitable transformation, as a linear parametric fixed‐charge problem. It is proved, with wider generality than in the case of Hirsch and Dantzig, that some optimal solution to the generalized linear fixed‐charge problem is an extreme point of the polyhedral set defined by the constraints. Furthermore, it is shown that the optimum of the generalized fractional fixed‐charge problem is also a vertex of this set. The proof utilizes a suitable penalty function yielding an upper bound on the optimal value of the objective function; this is particularly useful when considering combinations of independent transportation‐type networks. Finally, it is shown that the solution of a fractional fixed‐charge problem is obtainable through that of a certain linear fixed

ISSN:0028-1441    

DOI:10.1002/nav.3800180303

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

年代:1971

数据来源: WILEY

摘要:

AbstractIn a recent paper, Hamilton Emmons has established theorems relating to the order in which pairs of jobs are to be processed in an optimal schedule to minimize the total tardiness of performingnjobs on one machine. Using these theorems, the algorithm of this paper determines the precedence relationships among pairs of jobs (whenever possible) and eliminates the first and the last few jobs in an optimal sequence. The remaining jobs are then ordered by incorporating the precedence relationships in a dynamic programming framework. Propositions are proved which considerably reduce the total computation involved in the dynamic programming phase. Computational results indicate that the solution time goes up less than linearly with the size (n) of the problem. The median solution time for solving 50 job problems was 0.36 second on UNIVAC 1108 computer.

ISSN:0028-1441    

DOI:10.1002/nav.3800180304

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

年代:1971

数据来源: WILEY

摘要:

AbstractLet us assume that observations are obtained at random and sequentially from a population with density functionIn this paper we consider a sequential rule for estimating μ when σ is unknown corresponding to the following class of cost functions\documentclass{article}\pagestyle{empty}\begin{document}$$ f\left(x\right) = \frac{1}{\sigma }e^{ - \left({\frac{{x - \mu }}{\sigma }} \right)},\,x >\mu,\, \ge 0,\sigma > 0. $$\end{document}In this paper we consider a sequential rule for estimating μ when σ is unknown corresponding to the following class of cost functions\documentclass{article}\pagestyle{empty}\begin{document}$$ C_N = A|\delta (X_1 ,...,X_N ) - \mu |^p + N $$\end{document}Where δ(XI,…,XN) is a suitable estimator of μ based on the random sample (X1,…,XN),Nis a stopping variable, andAandpare given constants. To study the performance of the rule it is compared with corresponding “optimum fixed sample procedures” with known σ by comparing expected sample sizes and expected costs. It is shown that the rule is “asymptotically efficient” when absolute loss (p=‐1) is used whereas the one based on squared error (p= 2) is not. A table is provided to show that in small samples similar concl

ISSN:0028-1441    

DOI:10.1002/nav.3800180305

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

年代:1971

数据来源: WILEY

摘要:

AbstractA sufficient condition for the optimality of theCBS‐rule due to W. Smith is given a graphic interpretation in terms of ‘convex’ graphs. A convex graph is uniquely constructed (except for a homomorphism), and has the property that the optimum is achieved from any starting

ISSN:0028-1441    

DOI:10.1002/nav.3800180306

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

年代:1971

数据来源: WILEY

摘要:

AbstractA modification of the Shapley value is suggested, which takes into account the fact that (due to personal affinities among the players) certain coalitions are more easily formed than others. This is done by assigning to each player a point in space, and looking at the distances between pairs of points. The method seems to be especially applicable to voting games among political parties (in, e. g., parliaments), and, for such games, gives a value which is considerably easier to compute than the usual Shapley value. Some examples are considered.

ISSN:0028-1441    

DOI:10.1002/nav.3800180307

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

年代:1971

数据来源: WILEY

摘要:

AbstractA linear programming application for the selection of aircraft for a tactical airlift fleet is described.

ISSN:0028-1441    

DOI:10.1002/nav.3800180308

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

年代:1971

数据来源: WILEY

摘要:

AbstractThe paper presents the formulation and several solutions of a model for allocating a fixed number of aircraft to carriers and to missions. The amount of damage that can be inflicted is maximized. A nonseparable concave nonlinear objective function expresses diminishing marginal damage. Linear constraints on aireraft, carrier space, and aircraft availability for missions are included. The model is solved using the sequential unconstrained minimization technique (SUMT). The model is presented in terms of a scenario. Several different exponential damage functions are treated, and S‐shaped damage functions are discusse

ISSN:0028-1441    

DOI:10.1002/nav.3800180309

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

年代:1971

数据来源: WILEY

摘要:

AbstractThis paper describes a method for determining optimal repair and replacement policies for aireraft, with specific reference to the F–4. The objective of the analysis is to choose the set of policies from all possible alternatives over a finite planning horizon which minimizes the cost of operations. A dynamic program is presented which seeks an optimal path through a series of decision periods, when each period begins with the choice of keeping an aircraft, reworking it before further operation, or buying a new one. We do not consider changes in technology. Therefore, when a replacement does occur, it is made with a similar aircraft. Multivariate statistical techniques are used to estimate the relevant costs as a function of age, and time since last rewor

ISSN:0028-1441    

DOI:10.1002/nav.3800180310

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

年代:1971

数据来源: WILEY

摘要:

AbstractThe objective of this paper is to provide an independent evaluation of the nature and interpretation of ships' physical condition data generated by the USN Board of Inspection and Survey (INSURV). The substantive context is the classification of ships in terms of material condition and/or readiness based on scores pertaining to individual line elements within each ship. In order to account for multi‐dimensional measures of each ship, clustering procedures are employed to evaluate existing ship classification systems and to indicate other possibilitie

ISSN:0028-1441    

DOI:10.1002/nav.3800180311

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

年代:1971

数据来源: WILEY