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211.
A deterministic resource allocation model is developed to optimize defense effectiveness subject to budget, manpower, and risk constraints. The model consists of two major submodels connected by a heuristic. The first is a mathematical program which optimizes the multiperiod weapon mix subject to the constraint set. The second is a manpower supply model based on a transition matrix in which individual transitions are functions of personnel related budgets and historical transition rates. The heuristic marries the submodels through an iterative process leading to improved solutions. An example is provided which demonstrates how systems are undercosted and overprocured if manpower supply is not properly reflected relative to manpower demand. 相似文献
212.
Lower confidence limits are derived for the impact probability within a circle of fixed radius. The bivariate normal distribution with zero means, unequal variances, and zero correlation is the probability model for impacts. A new representation of the impact probability function is offered. This presentation is valid also for the dependent case, where the eigenvalues of the covariance matrix replace the variances. When the ratio of variances is known the lower confidence limits are uniformly most accurate (UMA). A few alternative approaches are compared by simulation when the ratio of variances is unknown. 相似文献
213.
We consider the scheduling of n jobs on m identical machines when the jobs become available for processing at ready times ai, ai, ? 0, require di time units for processing and must be completed by times bi for i = 1, 2, … n. The objective chosen is that of minimizing the total elapsed time to complete all jobs subject to the ready time and due date constraints, preemption is not allowed. We present a multi-stage solution algorithm for this problem that is based on an implicit enumeration procedure and also uses the labelling type algorithm which solves the problem when preemption is allowed. 相似文献
214.
James H. Patterson 《海军后勤学研究》1973,20(4):767-784
The applicability of critical path scheduling is limited by the inability of the algorithm to cope with conflicting resource demands. This paper is an assessment of the effectiveness of many of the heuristic extensions to the critical path method which resolve the conflicts that develop between the resources demanded by an activity and those available. These heuristic rules are evaluated on their ability to solve a large multiproject scheduling problem. 相似文献
215.
In this paper we consider the multiproduct, multiperiod production-scheduling model of Manne under the assumption that, across products, demands are interrelated over time. When demand requirements are proportional we show that the solution has a specific structure determined by the ratio of setup to production-run time of each product. This structure holds for any length horizon and may permit a substantial (time) savings for column generation solution procedures. 相似文献
216.
A method of life testing is proposed which combines both ordinary and accelerated life-testing procedures. It is assumed that an item can be tested either in a standard environment or under stress. The amount of stress is fixed in advance and is the same for all items to be tested However, the time x at which an item on lest is taken out of the standard environment and put under stress can be chosen by the experimenter subject to a given cost structure. When an item is put under stress its lifetime is changed by the factor α. Let the random variable T denote the lifetime of an item in the standard environment, and let γ denote its lifetime under the partially accelerated test procedure just described. Then Y = T if T ≦ x, and Y = x + α (T > x) if T > x. It is assumed that T has an exponential distribution with parameter θ. The estimation of θ and α and the optimal design of a partially accelerated life test are studied in the framework of Bayesian decision theory. 相似文献
217.
Philip H. Enslow 《海军后勤学研究》1966,13(2):177-202
This bibliography consists of 75 items on search theory and reconnaissance theory found in periodicals and technical reports. Each entry includes a short summary or a quotation from the pertinent abstract. The items are classified into one or more of the following categories: (1) General Discussion of Problems; (2) Allocation of Effort; (3) Game Theory Formulations; (4) Geometric Search Patterns; (5) Measures of Performance and (6) Miscellaneous. 相似文献
218.
219.
Thomas H. Johnson 《Small Wars & Insurgencies》2013,24(5-6):1006-1039
ABSTRACTThis article systematically assesses the 2014 Afghanistan Presidential Election, the first transfer of power from President Hamid Karzai to an elected successor, using provincial voting data as well as explicit data from polling centers. The analysis finds unusual voting results in the April election, where no candidate received 50%+1 votes required by the Afghan constitution, versus the voting results realized for the June ‘runoff election.’ As in other Afghan voting analyses, this article finds voting based on ethno-linguistic preferences, and interestingly found Dr. Ashraf Ghani receiving almost all the swing votes in the runoff election even though the other leading candidate from the April election all endorsed Dr. Abdullah Abdullah. More importantly, however, the research presented here clearly finds extremely strange voting patterns. For example, the polling data center analysis finds 606 polling places where Ghani received all 600 votes and Abdullah received none and another 900 polling centers that gave virtually all its votes to Ghani. These results in combination with other analyses raise the very real possibility that the election results were illegitimate. The article concludes with a discussion of the implications of the research to future Afghan elections and their processes as well as to the long-standing conflict in the country. 相似文献
220.