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461.
A model which allows the prediction of long-term average report rates against an array of radio emitters by a scanning sensor is presented. The model is based on Markov renewal theory. 相似文献
462.
Vladimir M. Ozernoy 《海军后勤学研究》1988,35(6):543-566
A brief historical overview of the development of multiple criteria decision making (MCDM) in the USSR during the last fifteen years is presented. Soviet MCDM research is reviewed. Several applications of MCDM methodology in the USSR are described. Long-term trends in the research and application of MCDM in the Soviet Union are discussed. 相似文献
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The standard problem in sampling inspection is to consider plans with and without curtailment. Curtailment causes difficulty and authors rarely give exact results (i.e., exact OC and ASN functions) for curtailed procedures. In this article we regard curtailment as an inverse sampling procedure and use Dirichlet integrals to obtain exact formulas for the OC, the ASN, and also the variance of the number of observations required under three types of plans: no curtailment, semicurtailment (for rejection only) and two-sided curtailment. Different sections of the article deal with the single sample, the two-stage, and the multiple-stage sampling problems. New tables for carrying out the single-sample procedure are included in the article. The authors feel that this article presents new directions and new ways of dealing with problems associated with quality control. 相似文献
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466.
States confronting cross-border intrusions of terrorism, illegal immigration, and/or drug trafficking weigh the costs of such intrusions against the costs of imposing barriers to prevent or curb the intrusions. In such situations, the degree of national security afforded a state depends, in large measure, upon the degree of border openness the state chooses. Depending upon the intensity and frequency of the intrusions – expressed in terms of opportunity-cost functions – a state might have little choice but to pursue a border policy of zero openness. It is this relationship of border openness to national security that explains why many states choose to construct security fences. In the 49 cases of security fences examined, many – among them Israel vis-à-vis the West Bank, India vis-à-vis Pakistan, Turkey vis-à-vis Greece in Cyprus – the construction of security fences becomes more complicated by their placement on lands whose sovereignties are disputed. 相似文献
467.
This article presents a flexible days‐on and days‐off scheduling problem and develops an exact branch and price (B&P) algorithm to find solutions. The main objective is to minimize the size of the total workforce required to cover time‐varying demand over a planning horizon that may extend up to 12 weeks. A new aspect of the problem is the general restriction that the number of consecutive days on and the number of consecutive days off must each fall within a predefined range. Moreover, the total assignment of working days in the planning horizon cannot exceed some maximum value. In the B&P framework, the master problem is stated as a set covering‐type problem whose columns are generated iteratively by solving one of three different subproblems. The first is an implicit model, the second is a resource constrained shortest path problem, and the third is a dynamic program. Computational experiments using both real‐word and randomly generated data show that workforce reductions up to 66% are possible with highly flexible days‐on and days‐off patterns. When evaluating the performance of the three subproblems, it was found that each yielded equivalent solutions but the dynamic program proved to be significantly more efficient. © 2013 Wiley Periodicals, Inc. Naval Research Logistics 60: 678–701, 2013 相似文献
468.
In this article, we construct and analyze an original database of overseas Chinese equity oil investments (EOI) in order to assess the relative importance of economic and geopolitical factors in determining the type of countries that are most likely to receive those investments. We find that China's national oil companies (NOCs) choose to make considerable investments in certain oil rich countries while ignoring others. We develop and examine ‘economic opportunity’ and ‘geopolitical relevance’ explanations of Chinese EOI. The economic explanation assumes that Chinese oil companies operate autonomously despite the fact that they are state owned, and that they seek international experience in countries offering less competition but more risk. The geopolitical explanation suggests that Chinese equity oil investments are developed and coordinated by the central government as part of a geopolitical strategy that is designed to bypass the so-called ‘Malacca Dilemma’ and deepen security ties with oil-rich states through the conduct of oil diplomacy. We argue that Chinese EOI tends to reflect both corporate interests and government priorities, and that it generates more liabilities rather than benefits for China. 相似文献
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Peter M. Sales 《Small Wars & Insurgencies》2013,24(1):93-97
Recent counterinsurgency experiences in Iraq and Afghanistan have demonstrated that the local operating environment often is dominated by indigenous power-holders. As counterinsurgents seek to establish control over the local population, collaboration with these agents has become an essential aspect of contemporary counterinsurgency. Although the practice of constructing collaborative relationships with indigenous power-holders might be perceived as unconventional by today's counterinsurgents, the approach itself goes back to the colonial era in which modern counterinsurgency has its roots. This article explores the dynamics, benefits, and dangers of collaborative relationships with indigenous power-holders by analysing an infamous episode in Dutch colonial history, the case of the collaboration between Dutch colonial authorities and warlord Teuku Uma during the Aceh War (1873–1913). This relationship ended in disaster for the Dutch as Uma departed their side at the moment he had become their pivotal asset in the local political landscape. The article explains that the Dutch succeeded to co-opt Uma, but failed to control him as they lacked the will and means to do so. Furthermore this case study provides an insight in the way the Dutch colonial authorities dealt with the complex process of intelligence-gathering in a fragmented indigenous society. 相似文献