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151.
针对全球定位系统在信号失锁条件下与航位推算组合导航的系统误差快速累积问题,提出一种基于压缩扩展卡尔曼滤波的同时定位与制图的辅助的全球定位系统/航位推算组合导航方法。该方法利用同时定位与辅助实现运动平台在全球定位系统信号无效时连续稳定导航,抑制航位推算定位误差的累积,并利用全球定位系统定位结果校正同时定位与辅助制图误差,减小地图的不确定性。设计基于压缩扩展卡尔曼滤波的同时定位与辅助/全球定位系统组合滤波器,实现大尺度环境下同时定位与辅助/全球定位系统的实时解算。真实实验数据计算结果分析表明,相对于同时定位与辅助定位结果,同时定位与辅助的全球定位系统/航位推算组合导航可有效提高系统定位性能,使得制图精度提高10m。  相似文献   
152.
This article looks at the Kashmir conflict in South Asia, which has been going on since 1947, when India and Pakistan became independent from British colonial rule. After looking at some historical background, the article looks at both the external dimension as well as the internal dimension of the conflict. The external dimension tends to focus on Indo-Pak relations over Kashmir and the internal dimension looks at India's repressive state policies within the state of Kashmir. This article uses Mary Kaldor's “New War” thesis as a theoretical framework to understand the situation and pays special attention to the conflict's very complex and multifaceted nature. The article argues that although the levels of violence have differed from time to time in the region since 1947, today the conflict seems to have less to do with Indo-Pak relations or the external side of things and has more to do with the internal dimension and India's undemocratic ways within Kashmir. Today, Kashmir is one of the most militarised conflict zones in the world. The stationing of the Indian military and paramilitary forces in the region has only exacerbated the situation since it is the security personnel who cause much of the problem. The Armed Forces Special Powers Act gives these security forces extraordinary powers in the region, which they often abuse. The armed forces have no real understanding of the local culture or sympathy for local religious sentiments. Poverty, corruption, administrative failure, police brutality, identity politics and human rights abuses are some of the key features associated with this conflict. Methodologically, a number of interviews were carried out with the local people in the region recently. From the data gathered through the interviews, it is very obvious that the people still feel very oppressed and that the situation is still very volatile, fraught with uncertainty. Finally, after making an assessment of the situation, the article tries to suggest methods of peaceful building and conflict management as the way forward.  相似文献   
153.
We re‐examine the Miguel et al. (2004 Miguel, E., Satyanath, S. and Sergenti, E. 2004. Economic shocks and civil conflict: an instrumental variables approach. Journal of Political Economy, 112(4): 725753. [Crossref], [Web of Science ®] [Google Scholar]) study of the impact of growth on civil war, using growth in rainfall as an instrument. Miguel et al. (2004 Miguel, E., Satyanath, S. and Sergenti, E. 2004. Economic shocks and civil conflict: an instrumental variables approach. Journal of Political Economy, 112(4): 725753. [Crossref], [Web of Science ®] [Google Scholar]) – in our view, erroneously – include countries participating in civil wars in other states. Restricting the conflict data to states with conflict on their own territory reduces the estimated impact of economic growth on civil war. We show how spatial correlations in rainfall growth and participation in civil conflicts induce a stronger apparent relationship in the mis‐classified data.  相似文献   
154.
This study models the structural sources of variation in the use of selective (discriminate) repression within 89 civil wars fought between 1981 and 2005. The severity of repressive violence is modeled as a function of the amount of territory being contested by the insurgents. This idea is operationalized using measures of the location, size, and density of insurgency violence. The analysis finds evidence that the repressive behavior of both governments and rebel groups is linked to conflict geography. Governments violate physical integrity rights more frequently and kill more civilians the greater the overall amount of territory under contestation. Rebels kill more civilians in highly dispersed insurgencies that lack a clear epicenter.  相似文献   
155.
Abstract

This paper examines the impact of civil war on military expenditure. We employ two measures of military expenditure: the share of military expenditure in general government expenditure and the logarithm of military expenditures. We would reasonably expect a priori that military expenditure as a share of general government expenditure increases during a civil war and that such increases would taper off over the duration of a civil war. We also explore whether the termination of a civil war induces a decline in the share of military expenditure as a share of the general government expenditure in the short-run. We find evidence the of share of military expenditure increases during a civil war and falls in the year succeeding the end of a civil war, and, in particular, if a war ends in a peace treaty. The level of military expenditures, however, rises during civil wars and does not appear to decline in the short-term after the end of a civil war.  相似文献   
156.
Advocates of the preventive use of force against emerging nuclear, biological, or chemical programs often look to the allegedly successful 1981 Israeli airstrike against Iraqi nuclear facilities at Osiraq. According to the conventional wisdom, this attack may have prevented Iraq from going nuclear before Operation Desert Storm in 1991. This article assesses the claim that the 1981 attack substantially delayed Iraqi acquisition of nuclear weapons, both by revisiting older debates and by introducing new evidence from Iraqi scientists. The article casts doubt on the conclusion that the attack was successful for three reasons: (1) the reactor itself was not well equipped to generate plutonium for a nuclear weapon; (2) illegal plutonium production would likely have caused a cutoff in the supply of nuclear fuel and an end to weapons activities; and (3) the attack may have actually increased Saddam's commitment to acquiring weapons. These conclusions have implications for the Bush Doctrine, as the lack of success in 1981 casts doubt on the possible success of future attacks against nuclear programs.  相似文献   
157.
基于复杂网络理论,分析了信息化作战系统网络结构,构建了传统作战系统和信息化作战系统拓扑模型的生成算法,并通过对传统作战系统和信息化作战系统结构拓扑模型度量性质的比较,说明了信息化战争下的作战系统结构特点,为进一步研究网络化战争提供了良好的模型基础.  相似文献   
158.
为了使大空域变轨弹道的理论研究更符合反舰导弹的实际运动状态,建立了反舰导弹追踪虚拟目标的三维空间相对运动模型。同时,为了保证反舰导弹大空域变轨弹道的四段弹道平滑过渡,在导引律设计时同时考虑了脱靶量要求和末端落角要求。应用Lyapunov稳定性理论求解出满足要求的三维扩展比例导引律,对大空域变轨弹道的四段弹道设计了相应的过载控制指令,并进行了仿真研究。仿真结果表明:所提出的三维扩展比例导引律可以使反舰导弹顺利完成大空域飞行任务,而且保证了反舰导弹的所有性能指标均满足要求。  相似文献   
159.
ABSTRACT

By utilizing the theory of Strategic Action Fields (SAFs), the present article explains how a new meso-level social order seems to have emerged in Mexico as a result of the paramilitarization of organized crime, militarization of security, and the opening of Mexico’s energy sector to private investment. This work describes the transformation of Mexico’s energy field after a process of major constitutional and economic changes that were the consequence of a security crisis and an agenda of energy reform for which the so-called ‘drug war’ was a key underlying foundation.  相似文献   
160.
ABSTRACT

State support for foreign rebel groups has become more salient, yet it remains unclear how this affects armed conflict. This paper therefore analyses the effect of foreign government assistance and does so in the typical case of the Angolan War (1975–1991). It argues that South African and United States support greatly helped the National Union for the Total Independence of Angola (UNITA) wage a large and sustained insurgency campaign but was ultimately insufficient to overthrow the People’s Movement for the Liberation of Angola (MPLA) government because it enabled the incumbent government to obtain similar foreign assistance and because the level of aid awarded to UNITA fluctuated strongly, preventing it from engaging in meaningful long-term planning.  相似文献   
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