首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   63篇
  免费   0篇
  2020年   1篇
  2019年   1篇
  2018年   1篇
  2017年   1篇
  2016年   1篇
  2015年   1篇
  2014年   4篇
  2013年   33篇
  2012年   1篇
  2011年   1篇
  2009年   1篇
  2006年   2篇
  2004年   1篇
  2003年   2篇
  1997年   1篇
  1993年   2篇
  1992年   2篇
  1991年   2篇
  1989年   1篇
  1987年   1篇
  1979年   1篇
  1975年   1篇
  1970年   1篇
排序方式: 共有63条查询结果,搜索用时 62 毫秒
21.
22.
As the world becomes increasingly globalized, interruptions to international trade cannot be permitted. Piracy off the coast of Somalia has hampered international trade in the region and poses significant risks to the sailors required to navigate those waters. Over the past three years the global community has attempted, through a number of different naval tactics, to stop these acts of piracy; however, these tactics have proven ineffective. This article looks at historical precedence and military theory to support the concept of using convoys to protect the thousands of cargo vessels traveling round the Horn of Africa every year. This tactic will greatly decrease the number of successful pirate attacks and save countless lives in the process.  相似文献   
23.
Britain's failure to cut military commitments in spite of escalating defence costs was not the result of blocking policies by disgruntled services. Rather, there was no determination among Whitehall's political departments to cut commitments even before the service departments could obstruct a decision on force levels. The Conservative governments under Macmillan and Douglas‐Home showed a propensity for substantial force reductions in Europe rather than in out‐of NATO areas. This remained London's long‐term aim even after it had been accepted to build up British troops in Europe to agreed force levels. During Alec Douglas‐Home's premiership Britain's global military role, especially east of Suez, gained a greater significance. An Anglo‐American military axis operating in the Far East and the Indian Ocean became a prominent feature. Ultimately, Anglo‐American military interdependence outside NATO was to ensure that Britain would be able to pursue a policy with more room for independent action.  相似文献   
24.
This paper examines whether non-lethal weapons (NLWs) enhance the capability of the US armed forces to conduct irregular warfare (IW) operations. With expectations that the operational environment will only continue to become more complex in the future, NLWs may reduce the level of violence received, as well as dispensed, by US forces while performing tasks in the IW spectrum. We argue that NLWs increase the ability of US forces to address the long tail of warfare and their deployment should be increased in the near term.  相似文献   
25.
As Canada's military mission in Afghanistan winds down and the country faces several years of fiscal austerity, all of Canada's major political parties are agreed that Canadian defence budgets must stay level or be cut. This comes at a time when the defence department is slated to replace the Canadian Forces’ (CF) major equipment fleets. Canada's defence establishment thus faces some critical decisions. One option is to try to maintain its expeditionary capabilities across all three services: army, navy and air force. Absent substantial new infusions of funds, however, this approach is likely to lead to an overall and largely chaotic reduction of capabilities. Another option is to make some difficult choices as to which expeditionary capabilities to maintain as part of a strategic review of Canada's future military needs. Such an option would ensure that Canada has at least some military capacities which can reliably be devoted to the most demanding international operations, while maintaining those capabilities required for domestic duties and North American defence. Pursuing this option would accord with the new North Atlantic Treaty Organization Strategic Concept and the call for “Smart Defense” within the Alliance. This article assesses the arguments for and against the option of specialising Canada's future defence capabilities and explores scenarios as to what a future CF may look like.  相似文献   
26.
We consider the parallel replacement problem in which there are both fixed and variable costs associated with replacing machines. Increasing maintenance costs motivate replacements, and the fixed replacement cost provides incentive for replacing machines of different ages together in “clusters.” We prove two intuitive results for this problem. First, it is never optimal to split a cluster of like-aged machines, and second, it is never optimal to replace newer clusters before older clusters. By incorporating these two results into an algorithmic approach, we vastly reduce the amount of computation required to identify an optimal replacement policy.  相似文献   
27.
Without restricting the class of permissible schedules, we derive optimal schedules for economic lot scheduling problems that are fully loaded, have external setups, and have only two products. The fully loaded condition accurately represents certain types of bottlenecks. We show that the optimal schedule must have the Wagner-Whitin property. We also develop a measure of aggregate inventory, derive an optimal steady-state aggregate inventory policy, and provide conditions under which the aggregate inventory level of an optimal schedule must approach a steady state. By restricting the class of permissible schedules to rotation cycle schedules, we extend these results to more than two products.  相似文献   
28.
In this article we address the problem of scheduling a single project network with both precedence and resource constraints through the use of a local search technique. We choose a solution definition which guarantees precedence feasibility, allowing the procedure to focus on overcoming resource infeasibility. We use the 110-problem data set of Patterson to test our procedure. Our results indicate a significant improvement over the best heuristic results reported to date for these problems (Bell and Han [1]). Two major advantages of the local search algorithm are its ability to handle arbitrary objective functions and constraints and its effectiveness over a wide range of problem sizes. We present a problem example with an objective function and resource constraints which include nonlinear and non-continuous components, which are easily considered by the procedure. The results of our algorithm are significantly better than random solutions to the problem. © 1993 John Wiley & Sons, Inc.  相似文献   
29.
The claim that reactor-grade plutonium cannot or will not be used to produce nuclear weapons has been used to justify non-nuclear-weapon states’ large stockpiles of plutonium that has been separated from highly radioactive spent fuel. However, by using reduced-mass plutonium cores, it is possible to manufacture reliable nuclear weapons with reactor-grade plutonium. These weapons can have the same design, size, weight, and predetonation probability as weapons using weapon-grade plutonium and would require no special cooling. The increased radiation from reactor-grade plutonium could be easily managed by shielding and operational procedures. Weapons using plutonium routinely produced by pressurized-water reactors could have a lethal area between 40 percent and 75 percent that of weapons using weapon-grade plutonium. In the past, both Sweden and Pakistan considered using reactor-grade plutonium to produce nuclear weapons, and India may be using reactor-grade plutonium in its arsenal today. Despite claims to the contrary, the United States used what was truly reactor-grade plutonium in a successful nuclear test in 1962. The capability of reactor-grade plutonium to produce highly destructive nuclear weapons leads to the conclusion that the separation of plutonium, plutonium stockpiling, and the use of plutonium-based fuels must be phased out and banned.  相似文献   
30.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号