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1.
Discontinuities may occur in the distribution cost function for a variety of reasons. Some of these, notably discontinuous trunking costs and depot costs dependent on location, have been examined in the literature. In this paper the problem which arises when discontinuities occur in the local delivery cost function is examined and a method of solution incorporating heuristics is described. An illustrative example is given. 相似文献
2.
A compartmental model is developed to estimate flow parameters of a shallow aquifer affected by water loads in surface reservoirs and to evaluate its nonsteady flow distribution. The method incorporates temporal piezometric head measurements and sampling of water for dissolved chemicals and isotopes analyses. Each compartment is governed by a set of equations describing the conservation of linear momentum and mass balance expressions for water, isotopes, and dissolved chemicals. The number of compartmental balance expressions always must be greater than that of the unknown flow parameters associated with each compartment. An optimization method is described to yield spatial distribution of aquifer storativity, transmissivity, porosity, leakage, and compliance coefficients and fluxes leaking into an aquifer's lower boundary. Future predictions of an aquifer's piezometric head distribution in a compartmental system is formulated on the basis of the estimated flow parameters and the leakage components.Compartmental modelling which incorporates concentrations of environmental tracers, may yield efficiency in computing resources and accuracy enhancement for predicting an aquifer's flow regime. 相似文献
3.
4.
Risk simulation has become a standard alternative to the utilization of single estimates for input data to investment appraisal models. Under the risk simulation approach managers define probability distributions for relevant input factors. During this process management may consciously or subconsciously assume certain relationships between the input variables. These interdependencies are often omitted from the models, however, under the justification that they are accounted for implicitly in the values attributed to the variables by management. It is demonstrated in this paper that such omissions may lead to significant errors in the observed distributions of the selected appraisal criteria. Various forms of discriminate sampling are introduced and an example is cited for which certain discriminate schemes are shown to be more accurate than traditional independent sampling. 相似文献
5.
Samuel Eilon 《The Journal of the Operational Research Society》1959,10(4):217-227
In the determination of batch-sizes in batch production, different criteria can be used as guiding principles, depending on the specified objectives. In a production schedule consisting of several products, an optimum solution for the whole production schedule is sought. At the same time it is necessary to ensure that the total production costs of each individual product will not exceed a certain pre-determined value. Solutions for overall optimization of the schedule with respect to maximum profit per batch, or with respect to maximum return on the total cost of production of the batch, have already been published. This paper suggests a method for determining the economic batch-sizes when it is desirable to maximize the rate of return per unit time for a multi-product schedule. 相似文献
6.
Eilon Solan 《International Journal of Game Theory》2018,47(4):1287-1327
We present a new tool for the study of multiplayer stochastic games, namely the modified game, which is a normal-form game that depends on the discount factor, the initial state, and for every player a partition of the set of states and a vector that assigns a real number to each element of the partition. We study properties of the modified game, like its equilibria, min–max value, and max–min value. We then show how this tool can be used to prove the existence of a uniform equilibrium in a certain class of multiplayer stochastic games. 相似文献
7.
A method of numerically calculating the optical transfer function appropriate to any type of image motion and vibration, including random, has been recently developed. This method has been verified experimentally with real vibrations, and the close agreement justifies implementation in image restoration from blur deriving from any type of image motion, including random displacement. Here, image restorations of actual physically degraded images are presented, based on a constrained least squares improvement of the original Wiener filter. Even for extreme vibrations where the blur extent is much larger than the blurred detail, restoration is quite complete. The key to restoration is the determination of the optical transfer function unique to the particular image motion and vibration causing the blur. Results are also presented for low vibration frequency motion of random blur extent, as well as for high vibration frequencies. 相似文献
8.
Electrocyclizations of 1,3,5-hexatrienes containing up to four electron-donating and/or electron withdrawing substituents have been studied computationally using the hybrid density functional, B3LYP. Electron donating substituents at positions C-1 and C-5 decrease activation barriers by 0.3 to 2.3 kcal/mol. Introducing of an electron-withdrawing group, CO(2)Me, at C-4 further decreases the activation energy by 7 kcal/mol. Electron-withdrawing groups (NO(2), SO(2)Ph and C=N(+)Me(2)) at C-2 have a profound effect of 17-25 kcal/mol on the activation energy. 相似文献
9.
Samuel Eilon 《The Journal of the Operational Research Society》1972,23(1):3-15
Most problems in management involve multiple goals and two approaches to solving managerial problems have been suggested: optimizing and satisficing. The first covers methods of trade-offs, optimizing in tandem, conversion of goals into constraints and goal programming. The second mainly centres on norm setting and on interval programming. It is argued that cost-benefit analysis essentially belongs to the first group and that, contrary to some suggestions, the differences between the industrial and public sectors (as far as O.R. is concerned) are not related to differences between the optimizing and satisficing philosophies. 相似文献
10.
Samuel Eilon 《The Journal of the Operational Research Society》1964,15(4):347-354
Some of the objections to the classical model used in the theory of batch quantities are reviewed. They fall broadly into four categories (1) the validity of the model; (2) the determination of cost parameters; (3) criteria; (4) implementation. Some of the objections can be met by minor modifications of the model; others are more fundamental in nature. In multi-product situations the classical model can only provide an initial guidance and must be supplemented be other tools. 相似文献