全文获取类型
收费全文 | 1849篇 |
免费 | 416篇 |
国内免费 | 162篇 |
出版年
2024年 | 3篇 |
2023年 | 14篇 |
2022年 | 18篇 |
2021年 | 42篇 |
2020年 | 48篇 |
2019年 | 33篇 |
2018年 | 61篇 |
2017年 | 109篇 |
2016年 | 89篇 |
2015年 | 70篇 |
2014年 | 166篇 |
2013年 | 179篇 |
2012年 | 142篇 |
2011年 | 189篇 |
2010年 | 126篇 |
2009年 | 164篇 |
2008年 | 124篇 |
2007年 | 124篇 |
2006年 | 123篇 |
2005年 | 121篇 |
2004年 | 104篇 |
2003年 | 67篇 |
2002年 | 63篇 |
2001年 | 56篇 |
2000年 | 34篇 |
1999年 | 25篇 |
1998年 | 30篇 |
1997年 | 12篇 |
1996年 | 17篇 |
1995年 | 18篇 |
1994年 | 18篇 |
1993年 | 6篇 |
1992年 | 10篇 |
1991年 | 6篇 |
1990年 | 7篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1987年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有2427条查询结果,搜索用时 15 毫秒
401.
FBCB2是美国卫星导航、卫星通信、卫星遥感等航天系统与地面及空中通信系统、图像获取系统集成的一体化系统,是天、空、地系统综合应用的典范.介绍了FBCB2系统的性能特点及其在部队中的配备情况,在作战中的应用情况,就目前美国对FBCB2系统所进行的完善改进工作进行了分析. 相似文献
402.
The Federal Aviation Administration (FAA) and the airline community within the United States have adopted a new paradigm for air traffic flow management, called Collaborative Decision Making (CDM). A principal goal of CDM is shared decision‐making responsibility between the FAA and airlines, so as to increase airline control over decisions that involve economic tradeoffs. So far, CDM has primarily led to enhancements in the implementation of Ground Delay Programs, by changing procedures for allocating slots to airlines and exchanging slots between airlines. In this paper, we discuss how these procedures may be formalized through appropriately defined optimization models. In addition, we describe how inter‐airline slot exchanges may be viewed as a bartering process, in which each “round” of bartering requires the solution of an optimization problem. We compare the resulting optimization problem with the current procedure for exchanging slots and discuss possibilities for increased decision‐making capabilities by the airlines. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2006 相似文献
403.
基于"联合指数"的联合作战编组集团能力量化分析 总被引:4,自引:0,他引:4
随着科学技术的发展,以信息技术作为联结手段、由各军兵种部队参加的一种新的作战方式———联合作战,已经正式登上人类战争的舞台.而对于联合作战编组集团的作战力量的量化分析,是摆在联合作战模拟人员面前的一个重要而紧迫的任务.文中以“联合指数”方法为基础,就联合作战编组集团能力量化问题特别是对不同武器装备作战单元的能力量化进行了探讨. 相似文献
404.
Jacques Fontanel 《Defence and Peace Economics》2013,24(2):135-147
The evolutions of military expenditures in Eastern and Central European countries are difficult to estimate and to compare, due to the lack of available data for these states. Some results of the extent of cuts in defence spending since 1990 are interesting to interpret, but it is difficult for econometricians to use these figures even carefully. The structures of national military expenditure have been modified to the detriment of arms equipment. Thus, the disarmament process needs a special analysis of the arms industry. 相似文献
405.
This paper attempts to examine the effect of an anticipated foreign military threat on the steady‐state growth rate and the transitional behavior of the economy. The modeling strategy follows the Sandler and Hartley (1995) and Dunne et al. (2005) viewpoints to emphasize the role of national defense in affecting growth from the perspective of both the demand and the supply sides. We thus combine the public capital version of endogenous growth with a framework of competitive arms accumulation. It is found that the key factor determining the steady state and the transitional effects of a rise in the foreign military threat on the home weapon–capital ratio, the consumption–capital ratio, and the rate of economic growth, is the degree of relative risk aversion. 相似文献
406.
NOEL STOTT 《African Security Review》2013,22(3):4-11
A truly universal ban on anti-personnel mines cannot be realized without engagement of armed non-state actors and armed groups operating outside state control, including rebels and national liberation movements. Events after 9/11 have complicated engagement with organizations that can be classified as ‘terrorists’. Yet, the use of anti-personnel landmines itself can be viewed as an act of terrorism and African leaders have, on various occasions, classified the use of landmines and the presence of unexploded ordnance as engendering insecurity and a serious impediment to development. The success of a total ban ultimately depends upon ensuring that armed non-state actors act in accordance with international humanitarian law. The Geneva Call Deed of Commitment for Adherence to a Total Ban on Anti-Personnel Mines and for Cooperation in Mine Action (DoC) might be described as an alternative instrument to the Anti-Personnel Mine Ban Convention and can serve an important and impartial channel of communication with non-state actors. Already 18 armed groups in Africa have signed the Geneva Call DoC. 相似文献
407.
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
408.
Nicholas G. Evans 《The Nonproliferation Review》2013,20(3-4):351-366
ABSTRACTScience and technology (S&T) review is key to anticipating developments in the life sciences that may benefit or run contrary to the aims of the 1972 Biological and Toxin Weapons Convention. It serves as a mechanism for both preparing against novel biological threats and identifying the best opportunities for developing and sharing the life sciences to the fullest extent. In the age of rapidly advancing biotechnology, S&T review needs to be wide ranging, involve a diverse set of inputs, and be transparent about its methods and data. This viewpoint considers four models of S&T review and their capacity to respond to the challenge of the life sciences: standing advisory boards; ad hoc working groups; peer review; and wikis. It then identifies a hybrid model that is suitably broad, diverse, and transparent. 相似文献
409.
Mariana Budjeryn 《The Nonproliferation Review》2013,20(2):203-237
ABSTRACTThere is a lingering disagreement among scholars on how the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) affects nonproliferation and disarmament outcomes. Drawing on constructivist scholarship on international norms, this article examines the extent of the NPT's effect in the case of Ukraine's nuclear disarmament. In the wake of the Soviet Union's collapse, Ukraine found itself host to the world's third largest nuclear arsenal. Despite Ukraine's initial commitment to become a non-nuclear state, it proceeded along a difficult path toward NPT accession. Most controversial and directly at odds with the NPT was Ukraine's claim to ownership of its nuclear inheritance as a successor state of the Soviet Union. This article argues that, while much domestic discourse about the fate of these nuclear weapons was embedded in the negotiation of Ukraine's new identity as a sovereign state vis-à-vis Russia and the West, the NPT played an important, structural role by outlining a separate normative space for nuclear weapons and providing the grammar of denuclearization with which Ukraine's decision makers had to grapple. 相似文献
410.
Amanda Moodie 《The Nonproliferation Review》2013,20(1):71-82
ABSTRACTSince the 1990s, the group of stakeholders working to combat biological weapons (BW) proliferation has broadened to include new actors who have not traditionally focused on security issues, including organizations from the public health sector, researchers in the life sciences, and the biosafety community. This has had significant benefits for the Biological and Toxin Weapons Convention (BWC) and the arms control establishment more broadly. However, the BWC's agenda has become increasingly dominated by issues of international health and global health security. By focusing solely on response strategies, the United States and other interested parties risk losing sight of other important elements of a counter-BW strategy, including deterrence and prevention. Focusing on public health-related issues to the exclusion of more traditional security matters puts the nonproliferation regime at risk, because it limits the amount of time that stakeholders have available to grapple with the critical questions facing the BWC and the biological weapons nonproliferation establishment—questions that must be answered if the regime is to survive. 相似文献