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71.
We study optimal age‐replacement policies for machines in series with non‐instantaneous repair times by formulating two nonlinear programs: one that minimizes total cost‐rate subject to a steady‐state throughput requirement and another that maximizes steady‐state throughput subject to a cost‐rate budget constraint. Under reasonable assumptions, the single‐machine cost‐optimal and throughput‐optimal solutions are unique and orderable, and the multi‐machine optimal solutions have appealing structure. Furthermore, we establish equivalence between the two formulations and provide an illustrative numerical example. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006 相似文献
72.
Danny M. Davis 《Defence and Peace Economics》2013,24(3):351-366
This paper is the first to demonstrate a viable prediction market that successfully forecasts defense acquisition cost and schedule outcomes, and to provide insights for defense executive decision‐making. Already used in private industry, prediction markets can also accurately forecast outcomes and their associated risks for government programs. Using virtual money, prediction markets allow traders to ‘bet’ on some future outcome. This market mechanism turns out to be a relatively simple and accurate way to discover, aggregate, and communicate to a defense executive the collective market’s beliefs about the likelihood of an eventual outcome of an acquisition program of interest. 相似文献
73.
Lani Miyoshi Sanders Sharon M. DeLand Arian L. Pregenzer 《The Nonproliferation Review》2013,20(3):475-489
In his 2009 Prague speech and the 2010 Nuclear Posture Review, President Barack Obama committed the United States to take concrete steps toward nuclear disarmament while maintaining a safe, secure, and effective nuclear deterrent. There is an inherent tension between these two goals that is best addressed through improved integration of nuclear weapons objectives with nuclear arms control objectives. This article reviews historical examples of the interaction between the two sets of objectives, develops a framework for analyzing opportunities for future integration, and suggests specific ideas that could benefit the nuclear weapons enterprise as it undergoes transformation and that could make the future enterprise compatible with a variety of arms control futures. 相似文献
74.
Chris M.A. Kwaja 《African Security Review》2013,22(2):153-161
This paper examines the rationale and centrality of private military and security companies (PMSCs) in humanitarian assistance operations in Sudan, asking why PMSCs are involved in humanitarian assistance operations in Sudan and what the principles underlying their activities are. To answer this question, the paper draws attention to the link between humanitarian crises and PMSC interventions. Where there is no meaningful alternative intervention, undergirded by humanitarian concerns that are also profit driven, PMSCs come in to provide the needed services. The protracted and complicated internal armed conflicts in Sudan, which have lasted for over two decades, have produced as many as 4,8 million internally displaced persons (IDPs) – the single largest number in the world. The kind of humanitarian assistance operations provided by PMSCs in Sudan have become critical to the provision of much-needed services which were inadequately provided by governmental authorities at both unilateral and multilateral levels. This paper argues that the humanitarian crises in Sudan created a regime that permits humanitarian assistance operations by both state and non-state actors. 相似文献
75.
Harald Müller 《The Nonproliferation Review》2013,20(3):545-565
In two landmark articles, longtime scholars Kenneth N. Waltz and Thomas C. Schelling have re-emphasized the utility of nuclear deterrence over nuclear nonproliferation (Waltz) and nuclear disarmament (Schelling). While the thrust of the articles is seemingly different, both are rooted in the same intellectual ground: an epistemology that assumes problem-free inferences, drawn from past experiences, are applicable in future scenarios; a foundational rooting in strategic rationality that entangles them in unsolvable contradictions concerning comparable risks of different nuclear constellations, namely deterrence versus proliferation and disarmament; and a bias in framing the empirical record that makes nuclear deterrence more conducive to security than nuclear disarmament. The common normative-practical denominator, then, is to let a nuclear weapon-free world appear both less desirable and less feasible than it might actually be. 相似文献
76.
Manuel Acosta Daniel Coronado Esther Ferrandiz M. Rosario Marin Pedro J. Moreno 《Defence and Peace Economics》2013,24(7):821-839
AbstractThis paper examines the generation of technological knowledge by leading companies in the defence industry. In particular, we test whether the characteristics of large defence companies are related to both the production of different types of patents (civilian, military and mixed), and the generation of dual-use technologies. To explore these links, we rely on economic data for the top 100 defence companies from the Stockholm International Peace Research Institute database, and patent information from the Worldwide Patent Statistical Database. Our results show that the relationship between the production of civilian patents and the size of the company is positive and significant. However, this relationship does not hold for the production of military patents. Furthermore, the military commercial profile is unrelated to the generation of military patents. Regarding the involvement in dual-use technologies, firms engaged in dual-use are those with higher military sales, a greater number of employees and a larger number of patents (civilian, military and mixed) than those not engaged in dual-use. Furthermore, we found a skill effect (more involvement in dual-use per employee) in European firms compared to US firms. These findings help to identify which firms should be targeted by government policies if increasing dual-use technologies becomes a political objective. 相似文献
77.
We have used the Michigan Model of World Production and Trade to assess the impact of exports and imports of armaments (based on 1980 data) on sectoral trade and employment and other economic variables in the major Western trading countries. If the United States were to place a unilateral embargo on its arms exports and imports, we calculate that it would experience a comparatively small amount of employment displacement in the aggregate and that most of this displacement would occur in the transport equipment and electric machinery sectors. If all the major Western countries were to place a multilateral embargo on their arms trade, the sectoral effects on the United States would be similarly small. But the sectoral effects in several other industrialized and developing countries measured as a percentage of sectoral employment, would be larger, indicating potential short‐run adjustment problems in labor markets in some cases. 相似文献
78.
79.
Christopher Goldsmith 《战略研究杂志》2013,36(2):159-160
For the first four years of the Algerian War British ministers and officials claimed that while supporting the French position in North Africa they did not support their policies. Successive Conservative governments sought to sustain France in North Africa because of the impact that long term insurgency in Algeria would have on Western defence by draining French human and material resources. They also feared that Western influence in North Africa could decline, opening the way for the spread of Communism, and that further humiliation for France, coming on the heels of Indochina, could lead to a ‘neutralist’ government in Paris, which would politically weeaken the Western alliance. Yet Britain's own foreign interests led it to wish to limit the spread of Arab nationalism and to avoid being tarred with the colonialist brush. The ambiguity of Britain's position led to shifting policies, which made the job of HM Ambassador in Paris, Gladwyn Jebb, particularly difficult. 相似文献
80.
Chinese Theater and Strategic Missile Force Modernization and its Implications for the United States
The People's Republic of China (PRC), no longer content with its longstanding ‘minimalist’ nuclear posture and strategy, is enhancing the striking power and survivability of its theater and strategic missile forces and rethinking its nuclear doctrine in ways that may pose serious challenges for the United States. Although the modernization of Chinese nuclear and missile forces may ultimately result in greater strategic deterrence stability, this change will not come about immediately or automatically. Indeed, it is entirely possible that China's growing missile capabilities could decrease crisis stability under certain circumstances, especially in the event of a US–China conflict over Taiwan. 相似文献