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451.
Dennis M. Rempe 《Small Wars & Insurgencies》2013,24(3):24-61
In October 1959 the Eisenhower administration dispatched a CIA Special Team to survey the violence problem in Colombia. This article, part one of a two‐part series, examines this first significant attempt by a US administration to influence that nation's internal security situation. It investigates the Special Team's actions and analyses its recommendations for transforming Colombia's conventionally‐orientated security forces. The Team's survey, which focuses on counter‐insurgency tactics, civil action, intelligence operations, psychological warfare, and covert action, is the foundation from which Colombia's modern internal security structures are derived. 相似文献
452.
We consider a manufacturer (i.e., a capacitated supplier) that produces to stock and has two classes of customers. The primary customer places orders at regular intervals of time for a random quantity, while the secondary customers request a single item at random times. At a predetermined time the manufacturer receives advance demand information regarding the order size of the primary customer. If the manufacturer is not able to fill the primary customer's demand, there is a penalty. On the other hand, serving the secondary customers results in additional profit; however, the manufacturer can refuse to serve the secondary customers in order to reserve inventory for the primary customer. We characterize the manufacturer's optimal production and stock reservation policies that maximize the manufacturer's discounted profit and the average profit per unit time. We show that these policies are threshold‐type policies, and these thresholds are monotone with respect to the primary customer's order size. Using a numerical study we provide insights into how the value of information is affected by the relative demand size of the primary and secondary customers. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007 相似文献
453.
Designing Code Division Multiple Access networks includes determining optimal locations of radio towers and assigning customer markets to the towers. In this paper, we describe a deterministic model for tower location and a stochastic model to optimize revenue given a set of constructed towers. We integrate these models in a stochastic integer programming problem with simple recourse that optimizes the location of towers under demand uncertainty. We develop algorithms using Benders' reformulation, and we provide computational results. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2007 相似文献
454.
Jonathan M. Powell 《African Security Review》2014,23(4):329-338
This paper investigates civil conflict as a product of the survival strategies of African leaders. Specifically, the paper offers a theory of risk substitution that predicts coup-fearing leaders will undermine the military effectiveness of the state when making an effort to extend their own tenure. While ‘coup-proofing’ practices have often been noted as contributors to political survival, considerably less attention has been paid to the influence of these strategies on other forms of conflict. Utilising data from a number of cross-national datasets, the analyses show that having a higher number of ‘coup-proofing’ counterweights significantly worsens a state's civil conflict prospects. A brief consideration of multiple episodes of conflict further suggests that in addition to coup-proofing undermining the counterinsurgency capacity of the state, some leaders are simply indifferent to – or can even potentially benefit from – the existence of an insurgency. 相似文献
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Since the 1st oil crisis in 1973, the economies of sub-Saharan Africa have barely kept pace with their burgeoning populations. Women in Sub-Saharan Africa give birth more often than women in any other region of the world, with an average of more than 6.5 live births each. The region's natural increase average 2.5% a year in the 1960s, 2.7% in the 1970s, and in the mid-1980s, it is 3.1% per annum--a rate that will double the regions population in 22 years. National leaders in Sub-Saharan Africa were slow to consider population policy as a key component of the social and economic development effort. The neglect of population issues is reflected in the limited scope of public or private family planning programs in the sub-continent. Donor countries and institutions play an important role in developing the information base by providing technical training to government staff, supporting research, and disseminating information to a broad spectrum of political actors. Some examples of policy reconsiderations in Nigeria, Zambia, Liberia, and Niger are given. These countries are starting to give active consideration to population policies to reduce fertility and high rates of population growth by expanding family planning services, raising the age of marriage, improving the status of women, providing family-life education, and incorporating economic incentives for smaller families into the provision of social services. The highly centralized nature of African governments dictates that the acquiescence of the governmental elite must be obtained before any policy can take hold. Overall, high population growth rates in combination with a stagnating social and economic development effort throughout the region have provided the catalyst for a new look at Sub-Saharan Africa population policy. The ability of African nations to implement policies that reduce fertility is more open to question; no African nation has as yet done so, and the socioeconomics factors contributing to high fertility remain strong. 相似文献
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James A. M. McHugh 《海军后勤学研究》1984,31(3):409-411
This article presents a simple proof of Hu's algorithm for scheduling in minimum time a set of tasks constrained by precedence tree constraints, each task requiring a unit time to complete, and where m processors are available. 相似文献