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301.
Spencer D. Bakich 《Small Wars & Insurgencies》2013,24(4):688-711
Under what conditions can leaders achieve wartime political–military integration? In the Vietnam War, political–military integration exhibited dramatic variation: in the air war, the US was able to tightly integrate its political objectives and military conduct, but in the ground war, the American military prosecuted a strategy that was both divorced from broader political objectives and was immune from Washington's influence. I argue that the nature of information management between the military and civilian leadership explains the pattern of political–military integration in the Vietnam War more completely than do explanations that focus on the organizational cultures of professional militaries. 相似文献
302.
The mechanical, thermal and ablation properties of carbon phenolic (C-Ph) composites (Type-I) rein-forced with different weight percentages of organo-modified montmorillonite (o-MMT) nanoclay have been studied experimentally. Ball milling was used to disperse different weight (wt) percentages (0, 1,2,4,6 wt.%) of nanoclay into phenolic resin. Viscosity changes to resin due to nanoclay was studied. On the other hand, nanoclay added phenolic matrix composites (Type-II) were prepared to study the dispersion of nanoclay in phenolic matrix by small angle X-ray scattering and thermal stability changes to the matrix by thermogravimetric analyser (TGA). This data was used to understand the mechanical, thermal and ablation properties of Type-I composites. Inter laminar shear strength (ILSS), flexural strength and flexural modulus of Type I composites increased by about 29%, 12%and 7%respectively at 2 wt.% addition of nanoclay beyond which these properties decreased. This was attributed to reduced fiber volume fraction (%Vf) of Type-I composites due to nanoclay addition at such high loadings. Mass ablation rate of Type-I composites was evaluated using oxy acetylene torch test at low heat flux (125 W/cm2) and high heat flux levels (500 W/cm2). Mass ablation rates have increased at both flux levels marginally up to 2 wt.% addition of nanoclay beyond which it has increased significantly. This is in contrast to increased thermal stability observed for Type-I and Type-Ⅱ composites up to 2 wt.%addition of nanoclay. Increased ablation rates due to nanoclay addition was attributed to higher insulation effi-ciency of nanolcay, which accumulates more heat energy in limited area behind the ablation front and self-propagating ablation mechanisms triggered by thermal decomposition of organic part of nanoclay. 相似文献
303.
This article seeks to assess the magnitude of military reform in Indonesia and its impact in establishing greater levels of professionalism within the armed forces. To this end, the authors will offer some reflections on the studies of civil-military relations and military transformation for inculcating a higher degree of military professionalism; analyse to what extent the process of military reform in Indonesia has reshaped the institutional role of the armed forces; and discern three major strategic gaps in Indonesia's military reform, namely the “legal loopholes and regulation vacuum,” the “shortcomings of democratic civilian control,” and the “defence-economic gap.” This article asserts that military professionalism will grow more substantially depending on the ability of civilian elites to exercise effective control over the military and the capacity of the government to transform the military establishment keeping pace with strategic challenges and operational requirements. 相似文献
304.
Robert J. Lieber 《战略研究杂志》2013,36(4):509-530
Many scholars, strategists and pundits contend that the US is in decline. They argue that America's national capabilities are significantly eroding, and that with the rise of important regional powers, its primacy in world affairs is rapidly diminishing as well. Yet America continues to possess significant advantages in critical sectors such as economic size, technology, competitiveness, demography, force size, power projection, military technology, and in the societal capacity to innovate and adapt. This article argues that the nature of material problems has been overstated, and that the US should be able to withstand modest erosion in its relative strength for some time to come without losing its predominant status. Instead, where limits to American primacy do exist, they are as or more likely to be ideational as they are material. The problem inheres as much or more in elite and societal beliefs, policy choices, and political will, as in economic, technological or manpower limitations at home, or the rise of peer competitors abroad. 相似文献
305.
The use of life-cycle costs in procurement is limited by the accuracy of cost estimates and assessments of availability risks under the conditions generating costs. Critical to these problems are the needs and responses of equipment to maintenance and repair. Using transition probabilities to define the relationships between serviceability and maintenance and repairs, this article develops a comprehensive decision support system for military procurement. It uses a dynamic programming model to determine the least-cost set of maintenance and repair decisions, where adjustments are included for warranty conditions, time value of money, the opportunity costs of equipment failure, and the end-of-cycle salvage values or disposal costs. The system allows users to define working and failed states, create their own rules or indicators of availability from estimates of state probabilities and establish thresholds of risk acceptability. 相似文献
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We consider the problem of nonparametric multi-product dynamic pricing with unknown demand and show that the problem may be formulated as an online model-free stochastic program, which can be solved by the classical Kiefer-Wolfowitz stochastic approximation (KWSA) algorithm. We prove that the expected cumulative regret of the KWSA algorithm is bounded above by where κ1, κ2 are positive constants and T is the number of periods for any T = 1, 2, … . Therefore, the regret of the KWSA algorithm grows in the order of , which achieves the lower bounds known for parametric dynamic pricing problems and shows that the nonparametric problems are not necessarily more difficult to solve than the parametric ones. Numerical experiments further demonstrate the effectiveness and efficiency of our proposed KW pricing policy by comparing with some pricing policies in the literature. 相似文献
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