全文获取类型
收费全文 | 522篇 |
免费 | 8篇 |
出版年
2021年 | 5篇 |
2020年 | 5篇 |
2019年 | 5篇 |
2017年 | 10篇 |
2016年 | 13篇 |
2015年 | 10篇 |
2014年 | 10篇 |
2013年 | 72篇 |
2012年 | 22篇 |
2011年 | 27篇 |
2010年 | 22篇 |
2009年 | 15篇 |
2008年 | 27篇 |
2007年 | 15篇 |
2006年 | 16篇 |
2005年 | 5篇 |
2004年 | 5篇 |
2002年 | 5篇 |
2001年 | 4篇 |
1998年 | 7篇 |
1997年 | 7篇 |
1996年 | 4篇 |
1995年 | 6篇 |
1994年 | 4篇 |
1993年 | 12篇 |
1992年 | 9篇 |
1991年 | 6篇 |
1990年 | 4篇 |
1989年 | 16篇 |
1988年 | 4篇 |
1987年 | 12篇 |
1986年 | 12篇 |
1985年 | 11篇 |
1983年 | 7篇 |
1982年 | 5篇 |
1981年 | 8篇 |
1980年 | 9篇 |
1979年 | 11篇 |
1978年 | 4篇 |
1977年 | 8篇 |
1976年 | 7篇 |
1975年 | 8篇 |
1973年 | 4篇 |
1972年 | 12篇 |
1971年 | 3篇 |
1970年 | 3篇 |
1969年 | 9篇 |
1968年 | 8篇 |
1967年 | 3篇 |
1966年 | 3篇 |
排序方式: 共有530条查询结果,搜索用时 15 毫秒
231.
George Dimitriu 《Small Wars & Insurgencies》2013,24(3):429-458
Rarely has a military commitment led to such intense discussion in the Netherlands as the Task Force Uruzgan (TFU) mission in Afghanistan. In February 2010, the Netherlands' coalition government even collapsed after the two largest parties failed to agree on the withdrawal of Dutch troops from Afghanistan later this year. This article deals first of all with the difficult discussion over the Afghanistan mission of the TFU. The authors then subject three ISAF operations to close scrutiny. The authors provide some suggestions to help understand better this pivotal point in the execution of the whole operation and thus give a fuller picture of the Dutch counterinsurgency approach in Uruzgan. 相似文献
232.
Robert L. Feldman 《Small Wars & Insurgencies》2013,24(2):295-306
Though parts of Somalia appear mired in intractable conflict, both domestic and foreign trade continues. As a result amidst the conflict, corruption, and chaos Somalia's business community is a small force for peace and stability. Thus, efforts directed at enhancing the business community, possibly via the Transitional Federal Government or its successor, could play a small role in improving the situation in this strategically poised country with a very entrepreneurial population. However, such success is far from certain, and numerous other factors besides a strengthened business community would have to occur for Somalia even to begin the journey on the long road to recovery. 相似文献
233.
ABSTRACTThe present international standard allows non-nuclear weapon states (NNWS) to forego safeguards when nuclear material is used in a “non-proscribed military activity,” though no criteria have been established to determine when NNWS can remove naval nuclear material from safeguards. Though at present, only nuclear-armed states possess nuclear submarines, the global nuclear naval landscape may soon change with the advancement of Brazil's fledgling program and the possible precedent it would set for other NNWS. A framework is needed to shore up nuclear security and prevent nuclear material diversion from the nuclear naval sector. Proposed and existing nonproliferation frameworks, including a Fissile Material Cut-off Treaty and commitments through the nuclear security summits, are insufficient to close this loophole. A Naval Use Safeguards Agreement (NUSA), modeled after the Additional Protocol of the International Atomic Energy Agency, would provide a framework to remove the opacity surrounding nuclear material in the naval sector. Designed for NNWS and encouraged as confidence-building measures for nuclear weapon states, NUSA would explicitly outline those stages in the naval nuclear fuel cycle where safeguards are to be applied and in what context. This viewpoint also further provides direction for targeted research and development in technical naval nuclear safeguards solutions. 相似文献
234.
235.
236.
237.
238.
为研究多孔陶瓷膜过滤阻力,提出了多孔陶瓷膜双向过滤方式,分析了9通道多孔陶瓷膜在双向过滤时的有效过滤面积和通道截面积,建立了过滤阻力关系式。试验结果表明,跨膜压差0.05~0.10 MPa、错流速度1.8 m/s时,浓差极化阻力Rp为主要过滤阻力;跨膜压差0.10~0.25 MPa、错流速度1.0~2.2 m/s时,吸附沉积阻力Rd为主要过滤阻力;跨膜压差0.15 MPa、错流速度2.2~3.0 m/s时,膜自身阻力Rm是主要过滤阻力;增大错流速度能够有效延缓浓差极化的发生,减小吸附沉积层的厚度,减轻膜污染,延长过滤周期。 相似文献
239.
Nadir A.L. Mohammed 《Defence and Peace Economics》2013,24(3):203-231
This paper investigates theoretically and empirically the determinants of military spending in Africa. It specifies a formal model and uses time‐series and cross‐sectional estimations to ascertain the reasons behind variations in military allocations across and within 40 African countries during 1960–1991. The differences in military expenditures appear to reflect a complex of economic, political, and strategic factors at both national and international levels. Strategic considerations are, however, found to be the most important factors in most African countries. 相似文献
240.
David L. I. Kirkpatrick 《Defence and Peace Economics》2013,24(4):263-288
This paper constructs a conceptual model for the selection of defence equipment providing best value for money. It then shows how the unit cost of the chosen equipment increases between one generation of equipment and its successor because of developments in the perceived threat, the available technology and industrial productivity, and demonstrates that unit cost increases can arise from a logical and rational procurement policy and are not necessarily caused by technological chimeras and military vainglory. The resulting persistent rise in unit cost is unlikely to be significantly slowed by any of the counter‐measures yet proposed. The paper then discusses the policies which nations have adopted to accommodate past increases in unit cost, and the options which confront any nation at the point when it can no longer afford to re‐equip a particular element of its armed forces. 相似文献