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381.
Ling Li 《Defense & Security Analysis》2017,33(2):174-189
Possession of a brand is a sine qua non for economic success, not least because it connotes trust in delivering the value promised. Although Western arms exporters offer branded systems whose sales are influenced by price, there is a plethora of other economic variables, such as offset requirements and life-cycle support. Entrants to the international arms market will struggle without such arms “packages.” China’s entry, however, goes beyond the traditional economic paradigm. A four-stage historical model offers the backdrop for identifying the drivers that have forged its market entry into 55 countries worldwide. The strategy initially focused on sales of rudimentary military equipment for political purposes, but recently it has begun to commercialize exports, repositioning them from a low- to a high-tech sales trajectory. A Sino “brand” is thus emerging, reflecting both competitiveness and diplomatic considerations, especially non-interference in client state domestic affairs. 相似文献
382.
We consider an integrated usage and maintenance optimization problem for a k‐out‐of‐n system pertaining to a moving asset. The k‐out‐of‐n systems are commonly utilized in practice to increase availability, where n denotes the total number of parallel and identical units and k the number of units required to be active for a functional system. Moving assets such as aircraft, ships, and submarines are subject to different operating modes. Operating modes can dictate not only the number of system units that are needed to be active, but also where the moving asset physically is, and under which environmental conditions it operates. We use the intrinsic age concept to model the degradation process. The intrinsic age is analogous to an intrinsic clock which ticks on a different pace in different operating modes. In our problem setting, the number of active units, degradation rates of active and standby units, maintenance costs, and type of economic dependencies are functions of operating modes. In each operating mode, the decision maker should decide on the set of units to activate (usage decision) and the set of units to maintain (maintenance decision). Since the degradation rate differs for active and standby units, the units to be maintained depend on the units that have been activated, and vice versa. In order to minimize maintenance costs, usage and maintenance decisions should be jointly optimized. We formulate this problem as a Markov decision process and provide some structural properties of the optimal policy. Moreover, we assess the performance of usage policies that are commonly implemented for maritime systems. We show that the cost increase resulting from these policies is up to 27% for realistic settings. Our numerical experiments demonstrate the cases in which joint usage and maintenance optimization is more valuable. © 2017 Wiley Periodicals, Inc. Naval Research Logistics 64: 418–434, 2017 相似文献
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高校教学团队建设是本科教育教学质量工程的一项重要内容,也是高校师资队伍建设最有效的组织形式。本文通过对五十多个教学团队的推荐表及建设任务书等相关资料进行搜集、整理及分析,对大学教学团队建设的基本情况进行了总结,分析了存在的问题,并提出了相应对策,为高校教学团队建设提供了依据。 相似文献
385.
In recent years military procurement agencies have used “progress payments” in contracting. Although, overall, the adoption of such a policy may well have contributed to a decrease in total costs of procurement, we identify a class of inefficiencies that are likely to have been generated by it. 相似文献
386.
For a three‐sector Feder‐Ram framework, we present time‐series, cross‐sectional estimates for two cohorts, consisting of Asian and Latin American countries. The estimates indicate that private investment, and defense and non‐defense public spending are growth promoting for alternative error components representations. For the best error components representation, greater growth enhancement is associated with the two forms of public spending in Asia than in Latin America, while the opposite comparison characterizes private investment. Although defense is growth promoting, an opportunity cost exists insofar as non‐defense spending, financed by defense spending, appears to give a small net boost to growth in Latin America. 相似文献
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Accelerated life testing (ALT) is commonly used to obtain reliability information about a product in a timely manner. Several stress loading designs have been proposed and recent research interests have emerged concerning the development of equivalent ALT plans. Step‐stress ALT (SSALT) is one of the most commonly used stress loadings because it usually shortens the test duration and reduces the number of required test units. This article considers two fundamental questions when designing a SSALT and provides formal proofs in answer to each. Namely: (1) can a simple SSALT be designed so that it is equivalent to other stress loading designs? (2) when optimizing a multilevel SSALT, does it degenerate to a simple SSALT plan? The answers to both queries, under certain reasonable model assumptions, are shown to be a qualified YES. In addition, we provide an argument to support the rationale of a common practice in designing a SSALT, that is, setting the higher stress level as high as possible in a SSALT plan. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2013 相似文献
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