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851.
针对同心筒自力发射结构优化与热环境改善的问题,基于雷诺平均方程及轴对称N-S方程,依托弹性变形和网格再生成方法结合的动网格技术,对3种不同结构形式同心筒发射装置的二维轴对称流场进行了非定常数值计算,得到了不同结构条件下动态的流场机理及导弹热环境特性。计算结果显示:导流器方案能实现燃气流迅速顺利排导;筒底收缩段设计能有效遮挡反溅燃气流;筒口导流板结构较好抑制了内筒的"倒吸效应",确保导弹和内筒的热安全;揭示了优化同心筒的流场结构与降温机理,可为相关研究提供参考。  相似文献   
852.
从现有的拦截排序准则出发,根据实际作战中进袭目标的特点,应用现代排序理论,分别建立了动态目标拦截排序模型和总损失最小化模型,给出相应的求解算法。最后实例计算得出模型既体现了现有的拦截准则,又对现有的准则进行了推广。  相似文献   
853.
无人机测控系统Turbo-MAP译码方法   总被引:1,自引:0,他引:1  
无人机测控数据链系统与地面控制站进行的是遥测数据、侦察图像及遥控指令的传输,因此,高质量的通信是确保无人机数据链发挥效能的关键技术之一。针对无人机信道的特点和要求,研究了无人机信道的Turbo-MAP译码模型,提出一种无人机测控系统Turbo-MAP译码方法,并针对各种参数条件进行了Matlab仿真。实验结果证明,该方法能够保证在发送数据的时候尽量使用长度较长的数据包且增加交织深度,并显著提升译码BER性能。  相似文献   
854.
国防动员的指挥控制中大量的信息数据(如部队需求、地方资源)和错综复杂的多方关系,使得指挥员难以在短时间内从浩如烟海的信息中提取有用的决策信息和作出快速准确地指挥协调。为此,着眼未来指挥所的发展趋势,提出基于可视化交互的国动指挥所设计方法:通过分析国动指挥任务的关键路径,提取重要的决策信息,利用可视化交互技术,实现对国动任务的信息化指挥控制。以某部演习的国防动员指挥为例,验证了方法的可行性和有效性。  相似文献   
855.
针对地下储油复杂组合空间,采用大涡模拟的方法构建了油气扩散蔓延三维数值模拟模型,完成了油气扩散蔓延区域的空间离散和三维数值模拟求解优化,并进行了数值计算与分析。结果表明,在地下复杂组合受限空间油料泄漏后,罐室内的油气填充顺序为由边缘到出口、由底部到上部,油气不能达到100%的充满状态,罐室拱形顶部油气体积分数低于其爆炸下限的20%;罐室内油气的产生和蔓延十分迅速,从泄漏至到达罐室口仅需10 s,进入坑道仅需1 min;油气在流出罐室进入坑道后,具有迅速向四周扩散蔓延,流向一切可能注入的空间的特性。研究结果为地下储油工程的施工建设、安全管理、危险源监控等提供了有益参考。  相似文献   
856.
This article describes the results of research into the social phenomenon of “respect” as framed by junior members of the British Army, as part of a wider study into the Values and Standards of the British Army. This research was interview based, using qualitative analysis software to detect, manage, and draw conclusions from the qualitative data recorded in those interviews. The data indicated that the primary situation in which “respect” was visualised by the participants was the unit context, and that it comprised a combination of three different strands: respect for rank or “hierarchical respect,” “professional respect” for a person's military competence, and “personal respect” for an individual's character, personal behaviour, and attributes. The overall respect that an individual is given arises from the combination of these three areas. “Respect” as a concept was, in the soldiers’ characterisation, something that had to be earned (except for the “given” represented by rank) and was not stable: a person's fund of respect could go up or down in social value. Respect was also linked to trust: the more respect a person had, the more they could be trusted. Although the unit context was the primary one for discussing their framing of the concept of respect, many of the participants reported a wider dimension in which every human being deserves a basic level of respect simply for being human, and this level could not be forfeited.  相似文献   
857.
The Ground-based Midcourse Defense system is intended to protect the US homeland against limited attacks from intermediate- and long-range ballistic missiles. It has succeeded in intercepting target missiles and can engage a threat launched from North Korea or the Middle East, targeting any point in the USA. Nevertheless, high-profile struggles and program changes related to homeland ballistic missile defense (BMD) continue to make headlines. The most significant struggle has been a string of three straight intercept test failures over five years, followed by the recent successful intercept test in June 2014. This article first briefly reviews the current threats of concern. It then examines homeland BMD policy objectives, followed by the current major technical issues in supporting these objectives and, then, the likelihood of negating a warhead. Finally, it highlights major considerations that should be part of the trajectory the US government takes moving forward.  相似文献   
858.
AirSea Battle (ASB) has generated significant publicity, controversy, and debate among scholars, analysts, commentators, and observers of US defense strategy. However, a research gap exists concerning formal analysis of the impact of the operational concept on the relationship between the US Air Force (USAF) and the US Navy (USN). The impact of the ASB operational concept on the USAF–USN relationship is examined across the issue areas of strategy, budgets, weapons procurement, and training. These four issue areas represent important areas of historical conflict and competition between the Air Force and Navy. The conclusion is that ASB is ushering in a new era of Air Force–Navy partnership that advances the inter-service dynamic from “jointness” toward integration. The emergent USAF–USN partnership therefore represents a significant development in US defense politics and defense strategy.  相似文献   
859.
Commitment by the government of the Democratic Republic of Congo to addressing sexual and gender-based violence (SGBV) in the country is reflected in a number of international commitments and national strategies. This article traces the (slow) progress in addressing some of the most important issues relating to SGBV to which the government has committed itself. It argues that unless the underlying gender norms and unequal power relations that form the basis of gender violence, discrimination and inequality in Congolese society are addressed, SGBV will persist.  相似文献   
860.
This article highlights and critiques the underlying conceptualisations and assumptions of the women, peace and security (WPS) agenda that emerged with the adoption of United Nations Security Council Resolution 1325 in 2000. The main argument is that we need to rethink the WPS agenda to produce more holistic and groundbreaking responses for the types of challenges encountered, i.e., that gender inequality and insecurity are deep rooted and multi-layered, and thus negate mechanistic responses that do not deal with cultural and structural issues. It specifically focuses on gender and peace-making and gender and peacekeeping to point to the pitfalls in the current conceptions and practices in this arena.  相似文献   
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