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121.
122.
Donald E. Schulz 《Small Wars & Insurgencies》2013,24(3):47-88
This article presents a regional overview of US‐Latin American security relations, focusing on those countries where US national security interests are most likely to be endangered over the next two decades. The author examines the current US strategy of ‘shaping’ the Latin security environment, with a view to assessing the strength and weaknesses of this approach. The article presents some policy recommendations, including the recommendation that the US do more to redress the historical imbalance in Latin American civil‐military relations by strengthening civilian institutions. It also argues that at the regional level a major effort be made to recapture momentum toward the creation of a Free Trade Association of the Americas. 相似文献
123.
We consider the problem of service rate control of a single‐server queueing system with a finite‐state Markov‐modulated Poisson arrival process. We show that the optimal service rate is nondecreasing in the number of customers in the system; higher congestion levels warrant higher service rates. On the contrary, however, we show that the optimal service rate is not necessarily monotone in the current arrival rate. If the modulating process satisfies a stochastic monotonicity property, the monotonicity is recovered. We examine several heuristics and show where heuristics are reasonable substitutes for the optimal control. None of the heuristics perform well in all the regimes and the fluctuation rate of the modulating process plays an important role in deciding the right heuristic. Second, we discuss when the Markov‐modulated Poisson process with service rate control can act as a heuristic itself to approximate the control of a system with a periodic nonhomogeneous Poisson arrival process. Not only is the current model of interest in the control of Internet or mobile networks with bursty traffic, but it is also useful in providing a tractable alternative for the control of service centers with nonstationary arrival rates. © 2013 Wiley Periodicals, Inc. Naval Research Logistics 60: 661–677, 2013 相似文献
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Lawrence E. Cline 《Small Wars & Insurgencies》2013,24(2):273-289
Despite some tentative internal peace agreements, Nigeria continues to face violence from multiple groups. This violence feeds upon itself, with segments of the population being mobilized both for self defense and for pressing their ideological and practical goals. These multiple sources of violence, which the Nigerian government appears unable to control to any significant degree, have a long term corrosive effect on the country's internal stability. There are few reasons to be sanguine as to any rapid changes to the level of overall violence or the relative number of armed groups, although their specific identities may shift. Nigeria represents a good case study of a country in which relatively low but persistent violence by a multiplicity of groups can have major impacts on internal security. 相似文献
126.
Paul E. Roitsch 《Small Wars & Insurgencies》2013,24(3):497-517
From 2006 to 2011, al Qaeda's East African proxy, al Shabaab, served as de facto ruling party of Somalia despite the efforts of the internationally recognized Transitional Federal Government (TFG). During these five years, a violent struggle between al Shabaab and the Burundian and Ugandan Peacekeepers of the African Union Mission in Somalia (AMISOM) resulted in thousands of dead civilians, hundreds of thousands of internally displaced persons, and a strategic environment inhospitable to reconciliation, recovery, or development. Beginning in August 2011, AMISOM was able to break the deadlock and force al Shabaab from Mogadishu, then subsequently, Kismayo, and ultimately to consolidate and reorganize in the Somali hinterland. In order to continue the momentum, the African Union and other partner nations must support the newly recognized Somali Federal Government (SFG), neutralize al Shabaab, and provide good governance to its constituents. Al Shabaab's revenue streams must be shut down and their offensive capability must be degraded while the strategic environment is shaped to ensure that conditions conducive to a revival do not exist. Failure to do so will likely see Somalia continuing to produce Islamic extremists and pirates to menace international maritime traffic in the Western Indian Ocean, destabilize East Africa, and adversely impact millions. 相似文献
127.
Prof Maxi Schoeman Phenyo Keiseng Rakate Lucy Mulli Andrea E Ostheimer 《African Security Review》2013,22(2):122-132
This study examines how young people who have joined the South African National Defence Force (SANDF) on the two-year Military Skills Development System (MSDS) contract experience military service, and the effect this has on their ability to readapt to civilian life. The first part of the study examines the theoretical debates associated with military socialisation and reintegration into civilian life. Hereafter, the findings are presented in terms of the experiences of MSDS privates serving in the infantry, those that have left, and the perceptions of employment agencies in terms of the marketability of military skills. The conclusion is reached that MSDS members experience their two years in the SANDF as life-changing, that this affects their ability to reintegrate back into civilian society, and that the skills acquired during military training is of limited market value. The conclusion is reached that more needs to be done to assist these young military veterans to adapt to civilian life and to augment their military experience with more marketable skills to enable them to find gainful employment. 相似文献
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129.
Robert E. Kuenne 《Defence and Peace Economics》2013,24(3):239-247
The design of military posture is an exercise in confronting potential enemies’ capabilities within the context of geographic, technological, temporal, political and economic constraints. No formal model is capable of encapsulating the essentials of so complex an environment for closed or simulated analysis, but it is useful to have an informal framework within which to reason interactively within these dimensions. This paper presents such a scaffolding, patterned on the notion of a military posture as the output of an economic process whose structure reflects important determinants of the characteristics and extents of weaponry and expenditures that are appropriate to the environment within the feasibility set determined by the constraints. The analysis remains at an abstract level, but it does highlight the important shifts toward preparation for littoral warfare, greater reliance on reserve rather than active forces, and necessary changes in missions among military departments. 相似文献
130.
Machine maintenance is modeled in the setting of a single‐server queue. Machine deterioration corresponds to slower service rates and failure. This leads to higher congestion and an increase in customer holding costs. The decision‐maker decides when to perform maintenance, which may be done pre‐emptively; before catastrophic failures. Similar to classic maintenance control models, the information available to the decision‐maker includes the state of the server. Unlike classic models, the information also includes the number of customers in queue. Considered are both a repair model and a replacement model. In the repair model, with random replacement times, fixed costs are assumed to be constant in the server state. In the replacement model, both constant and variable fixed costs are considered. It is shown in general that the optimal maintenance policies have switching curve structure that is monotone in the server state. However, the switching curve policies for the repair model are not always monotone in the number of customers in the queue. Numerical examples and two heuristics are also presented. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007 相似文献