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871.
872.
The Junior Reserve Officers’ Training Corps is a high school program that combines classroom teaching with extracurricular activities. The program is located primarily in inner city schools and serves at‐risk students. Its goals are multidimensional and include military preparation and improving academic achievement. Using High School and Beyond data we find that the program’s effects depend on the timing and intensity of involvement. Test scores, graduation rates, and enlistments are higher for students who participate early in high school and for those who persist in the program. Conversely, we find few effects for students participating in the last two years of high school.  相似文献   
873.
In 2004, stretched by wartime deployments, the US Army countered declining retention by increasing re‐enlistment bonuses and implementing stop‐loss to prevent soldiers from separating at the end of their enlistment. We estimate the effects of bonuses, deployment, and stop‐loss on re‐enlistment between FY 2002 and 2006. We estimate that the baseline propensity to re‐enlist fell by 20%. However, we find that deployed soldiers are more likely to re‐enlist and that the estimated effects of re‐enlistment bonuses are similar to those estimated in peacetime. We evaluate the reasons for our findings, and calculate the cost effectiveness of re‐enlistment bonuses.  相似文献   
874.
This brief introduction celebrates the 20th Anniversary of the Journal, Defence and Peace Economics. Suggesting elements of an agenda for the future of this branch of economics, I raise several topics that are new and that seem to indicate that the field will expand and shift focus substantially in future years.  相似文献   
875.
Economic reconstruction typically takes place after the end of war. Yet recently, economic reconstruction has been viewed as a means to ‘win hearts and minds’ during ongoing conflict. Drawing on a variety of reconstruction experiences from Afghanistan and Iraq, we identify four ‘reconstruction traps’ that result from the incentives and constraints faced by actors involved in economic reconstruction during ongoing conflict. These traps include: 1. the credible commitment trap, 2. the knowledge trap, 3. the political economy trap, and 4. the bureaucracy trap. Avoiding these traps is critical for successful economic reconstruction; and we discuss potential strategies for doing so.  相似文献   
876.
The choice between balanced and specialized defence forces depends on the technology of defence output (e.g. whether a force scope multiplier is present), the existence of scope and scale economies, the platform customization costs and, of course, the level of defence budgets. Minimum force element levels (thresholds), and scale economies facilitate specialization as opposed to scope economies (e.g. platform‐sharing), scale diseconomies and the force scope multiplier (e.g. defence weakest‐link technology). When a balanced force is not optimal, the option value of a non‐optimally maintained force element must also include the opportunity cost arising from suboptimal force elements. Shrinking defence budgets may produce two surprising phenomena. If some force elements are shut down as a result of thresholds, the surviving ones may increase in platform numbers as well as enjoying closer‐to‐most‐desirable platforms. Furthermore, if heritage force elements are shut down within the budget contraction environment, overall defence capability might rise.  相似文献   
877.
Previous research into the impact of military expenditure on employment finds considerable variation across countries. This paper adds to the debate by examining the long run relationship between military burden and manufacturing employment in South Africa. Such an analysis provides an opportunity to test for crowding‐out effects and the impact of the marked decline in military spending on the South African economy. The paper finds evidence supporting the view that military expenditure will have a detrimental impact on long term manufacturing employment, adversely affecting industrial structure and efficiency.  相似文献   
878.
研究了基于L曲线的跳频信号重构正则化参数的选取问题,对跳频信号的稀疏性进行了分析,采用L曲线对系统的最优正则化参数进行了选取.在此基础上,通过推广的正则化FOCUSS算法估计了跳频信号的稀疏表示.仿真结果表明,通过L曲线选取的正则化参数在推广的正则化FOCUSS算法下,能够实现跳频信号在噪声环境下的重构.  相似文献   
879.
针对通信电台的测试诊断问题,通过建立“故障一测试”相关性矩阵,提出了一种GADPSO算法与最大诊断信息量准则结合进行通信电台故障诊断的方法.GADPSO算法收敛速度快、计算精度高,既避免了陷入局部最优和早熟收敛,又提高了优化效率;最大诊断信息量准则能全面评判测试点,快速有效地获得测试顺序.该方法为通信电台故障诊断提供了一种高效诊断策略.  相似文献   
880.
为了减少无线传感器网络节点能耗,延长网络生存时间,在PEGASIS算法的基础上,针对PEGASIS算法中节点之间容易产生长链和簇头选择没有考虑节点剩余能量的问题,提出了一种基于禁忌算法的PEGASIS算法改进。建链阶段采用禁忌算法代替原有的贪婪算法,防止了长链的产生,减小了节点传输距离;同时引入基于剩余能量的簇头选择机制,均衡了节点之间的能耗,延长了节点的生存时间。仿真结果表明,改进算法较PEGASIS算法第1个节点的死亡时间延长了约7倍,半数节点的死亡时间也得到了延长,从而提高了整个网络的生存时间。  相似文献   
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