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71.
提出了基于灰色系统理论与神经网络的武器装备研制费用组合预测模型,该模型首先采用灰色GM(0,N)模型对研制费用进行预测,利用LMBP神经网络对预测误差进行了模拟与修正,实例验证该方法具有较高的预测精度.  相似文献   
72.
Diffusion processes are commonly used to describe the dynamics of complex systems arising in a wide range of application fields. In this paper we propose, on the basis of diffusion processes, two models concerned with the stochastic behavior of fatigue cracks in a system. They are then used to get the distribution of the failure time, the first time the crack size of at least one of the cracks exceeds a given value. Several properties of our proposed models are presented, and the unknown parameters are estimated by the method of maximum likelihood. From these an estimate of failure time distribution is obtained. In this part, contrary to common practice, we do not assume availability of failure data. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2005  相似文献   
73.
Diversionary theories of war suggest that leaders may engage in bellicose foreign policies to divert the public’s attention from domestic problems and capitalize on a ‘rally around the flag’ type of effect. The evidence regarding diversionary theory is quite mixed. More recently, scholars have focused on situations that create opportunities for diversionary behavior, such as international rivalry and territorial disputes. This paper adds to the growing literature on diversionary conflict by considering the Ethiopia–Eritrea case and applying an opportunity-based approach. We assess whether the Ethiopia–Eritrea War (1998–2000) is consistent with diversionary explanations for the war, as many have previously claimed.  相似文献   
74.
Why did some Arab militaries remain loyal to authoritarian rulers amid mass uprisings during the Arab Spring while others defected to the opposition? One popular explanation shows this variation with reference to the degree of military institutionalization: institutionalized militaries defected, while patrimonial militaries remained loyal. This article argues that the institutionalization hypothesis does not provide a complete account of the mechanisms through which the degree of military institutionalization leads to either defection or continued loyalty. This shortcoming stems from the fact that scholars have treated military institutionalization as a catch-all concept for three distinct variables: ethnic stacking of the military, patronage distribution, and organizational factionalization. Examining the interaction between these variables highlights the mechanisms through which military defection occurs, and therefore that disaggregating institutionalization into its component parts provides a more complete explanation of military behavior during the Arab Spring.  相似文献   
75.
针对地基预警雷达单独预警巡航导弹发现距离近和跟踪目标困难的问题,提出了气球载雷达与地基预警雷达协同预警。按照军事概念建模的方法,建立了气球载雷达与地基预警雷达反巡航导弹(Cruise Missile,CM)的预警协同模式。在此基础上,建立了IDEF0功能模型。通过对IDEF0功能模型的理解,转换为作战仿真软件开发所需各类UML模型。从技术上验证了气球载雷达与地基预警雷达反CM预警协同作战的可行性,对其仿真实现有一定的参考价值。  相似文献   
76.
Decades of scholarship have warned against using historical analogies for policymaking. But the Taliban insurgency appears, on the surface, to confirm the usefulness of historical analogies to the British and Soviet wars in Afghanistan. I review the use of analogies for the war in Afghanistan and argue the analogies were historically unsound and strategically unhelpful. In fact, their effect on policy helped create the conditions for the very insurgency policymakers most hoped to avoid. The Taliban insurgency did not occur because of the presence of too many foreign troops and aid workers, but because there were too few.  相似文献   
77.
The paper’s main argument is that Israel’s security policy, which traditionally focused on defending its territorial integrity against regular Arab armed forces, was, by the 2010s, transformed into one that focuses on facing a variety of state- and non-state-based threats. Neo-realist explanations could neither account for the contested nature of the security debate during this period, nor the inconsistent evolution of the policy. The present study aims to solve this conundrum by introducing an alternative approach known as 4th generation strategic culture research. The paper is comprised of four parts. First, the origins and evolution of strategic culture are reviewed, with emphasis placed on the commonly accepted weaknesses that, to date, have prevented it from being used as a testable theoretical concept, and subsequently as an explanatory factor for security policy changes. The second part presents the “modernist constructivism” approach that bridges the gap between traditional constructivism and hypothesis-driven research design. Next, the paper introduces the emerging fourth generation in strategic culture literature, followed by a conceptual framework designed to resolve the inherent weaknesses of the more traditional approaches. Finally, this conceptual framework is applied to analyse the transformation of Israel’s security policy between 1982 and 2014.  相似文献   
78.
高动物油含量餐饮废油制备生物柴油   总被引:1,自引:1,他引:0  
针对重庆餐饮废油动物油含量高的特点,用氢氧化钠作催化剂制备生物柴油,得到最佳工艺条件为:醇油质量比25%,催化剂用量1.0%,反应温度60℃,反应时间60min,搅拌强度3000r/min。在该工艺条件下,进行数据放大实验,生物柴油的产率可以达到93.6%,说明该工艺条件适合工业生产。生物柴油产品质量达到国家标准;与0号柴油调和使用可以很好地改善其低温流动性能。  相似文献   
79.
针对多波束干扰系统同时干扰多个目标的资源分配问题,通过分析目标分配算法的一般流程及涉及到的关键问题和技术难题,提出了基于实战化和有限条件的针对多波束干扰系统的非线性0-1整数规划数学模型。针对该模型采取开源软件SCIP进行求解,最后给出数值仿真来说明模型和算法的有效性。  相似文献   
80.
This article explains why Singapore, despite its small size and semi-authoritarian regime, retains one of the best military forces in the Indo-Pacific. It unpacks Singapore’s ability to continuously innovate since the 1960s – technologically, organizationally, and conceptually – and even recently joined the Revolution in Military Affairs bandwagon. Drawing from the broader military innovation studies literature, this article argues evolutionary peacetime military innovation is more likely to occur in a state with a unified civil–military relation and whose military faces a high-level diverse set of threats. This argument explains how the civil–military fusion under the People’s Action Party-led government since Singapore’s founding moment has been providing coherent and consistent strategic guidance, political support, and financial capital, allowing the Singapore Armed Forces to continuously innovate in response to high levels and diversity of threats.  相似文献   
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