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211.
基于目标飞行器与追踪飞行器交会对接这一应用背景,对于追踪飞行器上交会雷达对目标飞行器的原始测量信息(斜距、方位角、俯仰角,甚至径向速度),通过建立适当的目标模型以及观测方程,很好地对2个飞行器的非线性相对运动规律、追踪飞行器绕地球高动态旋转特性、追踪飞行器姿态偏差进行了补偿或修正,实现了最优估计,并通过仿真进行了验证。  相似文献   
212.
对抗条件下SBIRS对战略导弹突防能力影响研究   总被引:4,自引:0,他引:4  
为了研究对抗条件下天基红外系统对战略导弹突防能力的影响,基于战略导弹突防能力计算模型,从理论上分析了红外假目标干扰、气溶胶遮蔽和红外隐身技术等对抗措施下天基红外系统对战略导弹探测概率的影响,给出了对抗条件下战略导弹突防能力的计算模型。为作战仿真研究奠定了一定的基础。  相似文献   
213.
利用ADAMS软件中的参数化分析工具,采用设计变量和局部模型重建的方法,实现了特种斜盘发动机斜盘倾角、后球心分布圆半径和导槽形式的参数化,建立了特种斜盘发动机参数化虚拟样机,并进而从设计研究、试验研究和初步优化分析等三个方面,对特种斜盘发动机进行了较为详细和全面的参数化分析.  相似文献   
214.
用有限时间热力学的方法分析具有热阻、热漏、内不可逆性的定常流联合卡诺型热机循环.导出了在傅立叶导热定律下联合循环功率、效率和生态学指标的性能,并进行优化;得到功率、效率和生态学指标之间的优化关系,并由数值计算分析了功率、效率和循环熵产率之间的关系.所得的结果表明,最大生态学指标下的效率十分接近于联合循环可以达到的最大效率;相应的熵产率也要低于以输出功率为优化目标时的熵产率.  相似文献   
215.
基于分布式哈希表(DHT)的P2P查找经常受到在底层网络中路由时无必要的路径长度增加的影响.另外,DHT在处理复制方面也有一定的缺陷.文中探讨了解决这些问题的方法.对使用Bloom filters作为资源路由的方法做了简要回顾,并较为详细地阐述了在资源分散的覆盖网络中使用距离加权Bloom filter的网络路由算法.对该算法进行了仿真测试,证明了其有效性.  相似文献   
216.
设计安全策略模型时应考虑安全策略的时序特性和灰色特性,还应综合考虑保密性、完整性和可用性三方面的需求。已有的安全模型没有描述时序性和灰色特性,而且一般只侧重描述保密性或完整性。为此,本文提出了动态灰色时序系统(简称DGTS)。本文详细描述了DGTS,以及基于DGTS的动态语义设计的灰色时序安全策略规范语言GTSL。  相似文献   
217.
The eastern Democratic Republic of Congo (DRC) has been characterised by chaos and insecurity for a number of years, but the rise of the M23 rebellion in 2012 once again highlighted just how dire the humanitarian and security situation is. For most of 2012, the crisis was addressed through negotiations between M23 and Kinshasa, mediated by the International Conference on the Great Lakes Region (ICGLR). However, 2013 marked the signing of the Peace, Security and Cooperation Framework Agreement (PSC Framework), and the United Nations Security Council's adoption of Resolution 2098, which contains the mandate of the long-awaited Intervention Brigade (IB). The PSC Framework calls on Kinshasa to implement substantial political reforms while also urging the neighbours of the DRC to stop interfering in its internal affairs. The IB is mandated to carry out targeted operations against the so-called ‘negative forces’ that operate in the eastern DRC. For now, hope of resolving this ongoing crisis hinges on the continuing ICGLR negotiations, the implementation of the PSC Framework and the success of the IB. However, there are critical questions about all of these processes that need to be answered and understood, as the expectations for these processes – especially in the case of the IB – are extremely high. Will the ICGLR manage to negotiate a peace agreement and will the IB succeed, or will they go down in history as yet another failure to save the eastern DRC?  相似文献   
218.
ABSTRACT

There 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   
219.
This article discusses the validity of national security threats in Botswana and whether they justified the creation of the Directorate of Intelligence and Security Services (DISS), which has been controversial since its formation. Since its inception in 2008, the DISS has been accused of many human rights violations and politicisation. Without fully deliberating on the basis for its creation, some discourses have focused on the politicised operations without relation to what the DISS is supposed to be doing. The author works under the assumption that debates should be shaped by whether it was necessary to create the DISS, and, if so, how we can shape and steer debates on its oversight, management, reform and operations. This article argues that despite the politicisation of the DISS, Botswana's national security threats are both real and imagined; and that domestic threats to national security have moved from the conceptual ‘imagined’ category to the ‘real’. However, that in itself did not warrant the design and mandate of the DISS, and the article argues that it was external threats that really warranted the creation of a civilian intelligence agency. The article concludes that Botswana faces a plethora of external security threats – traditional and non-traditional – that warranted the creation and continuance of the DISS.  相似文献   
220.
Armed conflict on the African continent has witnessed increasing recruitment of child soldiers, often at the hands of non-state armed groups. Unfortunately this practice continues unabated in the face of legal obligations prohibiting the recruitment of child soldiers under international humanitarian law, and international and regional human rights law. While international condemnation of the practice has led to attempts to increase the minimum age for recruitment to 18, a disjuncture persists between the legal obligations states sign up to, and the actual enforcement of these prohibitions at a domestic level.

International criminal law jurisprudence emanating from the Special Court for Sierra Leone and the International Criminal Court is being monitored closely, as these courts seek to enforce the prohibition in all armed conflicts, and against both state actors and non-state armed groups. International humanitarian law only protects child soldiers who have been unlawfully recruited. In this piece, the authors take a closer look at what amounts to unlawful recruitment in light of customary international humanitarian law, since this body of law also binds non-state actors, even without further criminalising legislation at a domestic level. Moreover, the article briefly explores whether a child can ever void this protected status by volunteering to participate directly in hostilities.  相似文献   
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