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   143篇
  免费   2篇
  2020年   1篇
  2019年   6篇
  2018年   3篇
  2017年   7篇
  2016年   2篇
  2015年   2篇
  2014年   7篇
  2013年   61篇
  2012年   1篇
  2011年   1篇
  2010年   2篇
  2009年   1篇
  2007年   1篇
  2004年   1篇
  2002年   1篇
  2001年   1篇
  2000年   2篇
  1999年   1篇
  1998年   3篇
  1997年   1篇
  1996年   2篇
  1995年   2篇
  1994年   1篇
  1993年   3篇
  1992年   5篇
  1991年   2篇
  1990年   1篇
  1989年   3篇
  1988年   3篇
  1987年   3篇
  1986年   2篇
  1985年   2篇
  1982年   1篇
  1978年   1篇
  1977年   1篇
  1976年   1篇
  1971年   1篇
  1970年   1篇
  1969年   1篇
  1968年   1篇
  1967年   3篇
排序方式: 共有145条查询结果,搜索用时 15 毫秒
51.
Practitioners of maintenance scheduling sometimes use a simple analytic formula, derived based on inspection scheduling, as a heuristic to determine the length of the preventive maintenance period. The sensitivity of this heuristic solution is analyzed and the cost penalties are calculated compared to the exact solution that utilizes the lifetime distribution in the derivation of the optimal preventive maintenance period. A simple extension of the heuristic is suggested to improve the approximation with a slightly increased computational effort. The sensitivity and cost analysis of the improved heuristic are discussed as well. © 1994 John Wiley & Sons, Inc.  相似文献   
52.
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   
53.
This article explores why the offensive predominates military tactical thinking. With survey results showing an offensive bias among 60 per cent of senior Swedish officers and as many as 80 per cent in the case of the army, it is clear that this is not just a problem of the past but is equally relevant today. The article asks why there is a tendency to perceive and understand offensive tactics as the preferred choice and the way to conduct battle that should be encouraged and preferred. Drawing on existing research and the findings of a pilot study, ten propositions for why the offensive bias exists are tested using a mixed-method approach. Based on the findings, the article develops a model to understand why the offensive dominates military tactical thinking. It is found that the two key constitutive factors behind the offensive bias are military culture and education. These factors most directly and profoundly influence an officer’s identity, perceptions, and thinking. Military culture and education, in turn, work as a prism for four other factors: military history, the theory and principles of war, doctrine and TTPs, and psychological factors.  相似文献   
54.
This article argues that French naval policy‐makers were slow to adjust to the changed strategic landscape of the 1930s. During the 1920s France did not face a serious land or air threat. Defence policy‐makers were therefore able to devote a large portion of the defence budget to rebuilding French maritime power. But when the Depression and the rise of Nazi Germany overturned the strategic situation in Europe, policy‐makers adjusted by giving priority to land and air rearmament and by placing ever greater emphasis on securing an alliance with Great Britain. The French naval establishment resisted this trend unsuccessfully. The frustration of naval planning increased the resentment and mistrust of both the Third Republic and Great Britain that characterised naval attitudes before and particularly during the Second World War.  相似文献   
55.
This article develops a methodology for testing constant exchange risk properties and identifying an appropriate form for a decision maker's utility function. These risk properties characterize six different utility functions which are sums of products of polynomials and exponential functions. Such functional forms are commonly used in decision analysis applications. The practical advantage of this methodology is that these constant exchange risk properties eliminate the usual arbitrariness in the selection of a parametric utility function and often reduce the data requirements for subsequent estimation. The procedure is straightforward to apply. The decision maker need only provide certainty equivalents for two-outcome gambles and determine the more-preferred gamble in paired comparisons. The technical details of the procedure can be handled by interactive computer software.  相似文献   
56.
Three different solutions to a very simple transfer pricing problem are outlined and contrasted. These are labeled by their authors: Hirshleifer, Enzer, and Ronen and McKinney. Weaknesses associated with each solution are pointed out.  相似文献   
57.
Proposed is a Heuristic Network (HN) Procedure for balancing assembly lines. The procedure uses simple heuristic rules to generate a network which is then traversed using a shortest route algorithm to obtain a heuristic solution. The advantages of the HN Procedure are: a) it generally yields better solutions than those obtained by application of the heuristics, and b) sensitivity analysis with different values of cycle time is possible without having to regenerate the network. The rationale for its effectiveness and its application to problems with paralleling are presented. Computational experience with the procedure on up to 50 task test problems is provided.  相似文献   
58.
A theory of additive utilities is discussed for cases where the set X, on which an individual's preference-indifference relation is defined, is a subset of the Cartesian product of n finite sets. A number of potential applications of additive utilities in decision making are presented.  相似文献   
59.
Pakistan confronts numerous domestic security challenges including jihadist extremism, Sunni-Shi'a sectarian violence, drug trafficking, illegal commodity smuggling, endemic corruption, and systemic problems with the provision of justice and law enforcement. While much has been written about US military assistance to the Government of Pakistan (GOP) and the ever-evolving political relations between the two countries, basic questions of highest policy significance related to Pakistan's internal security have never been fully studied or considered. This essay begins to address these empirical lacunae. It first provides a comprehensive examination of Pakistan's internal security environment and the effectiveness of the GOP's criminal justice structures in dealing with these challenges. The paper then goes on to assess the impact and utility of the current suite of US law enforcement assistance in helping to fortify Pakistan's domestic security environment. The study raises a number of difficult questions pertinent to the long-term impact of this support, particularly in terms of its effect on fostering a viable, accountable and transparent system of civilian governance and policing.  相似文献   
60.
Much of the literature on the decolonization of Namibia is set in a narrative mode and demonizes one or the other of the protagonists. This article, organized in a topical fashion, concerns the diplomatic, military, and economic facets of the Namibian war and draws upon the literature of comparable twentieth century colonial and anti-colonial wars in Algeria, Angola, Kenya, Mozambique, the Philippines, South Africa, Vietnam and Zimbabwe. It explores the changing discourse of legitimacy concerning independence for Namibia, the conduct of insurgency and counterinsurgency in the bush war, and economic aspects of that war.  相似文献   
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