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1.
对以冲压发动机为动力导弹的轨迹/总体参数一体化优化设计问题进行了研究。建立了一体化优化的相关数学模型,提出采用高斯伪谱法将一体化优化中的轨迹最优控制问题参数化,然后用序列二次规划方法求解该一体化优化问题。仿真结果表明,经过一体化优化设计,起飞质量比不考虑轨迹优化的方案减少了4.06%。总体参数优化结合轨迹优化最大程度地挖掘了导弹总体设计的潜力,提高了总体性能。其结果可为冲压发动机导弹总体优化设计研究提供理论参考。  相似文献   

2.
为实现对可变推力固体火箭发动机推进剂的充分利用,以近程导弹拦截目标为特定研究场景,在推进剂质量给定的情况下采用Gauss伪谱法进行弹道优化设计。该方法采用变推力控制,选用固体火箭发动机实现推力可调,由比例导引给出制导指令,研究Gauss伪谱法在变推力导弹弹道优化中的应用方法,最终得到目标函数及约束条件下的比例导引变推力优化方案。仿真结果表明了高斯伪谱法应用于可变推力导弹弹道优化设计的有效性,同时与传统发动机方案下的弹道进行对比,表明了变推力控制在导弹弹道性能上的优越性。  相似文献   

3.
固体火箭冲压发动机的工作特性分析   总被引:3,自引:2,他引:3       下载免费PDF全文
通过数值计算 ,分析了燃气流量固定的壅塞式固体火箭冲压发动机、等空燃比工作的固体火箭冲压发动机和非壅塞固体火箭冲压发动机的高度特性和速度特性。结果表明 ,当导弹的飞行高度和速度变化时 ,燃气流量固定的壅塞式固体火箭冲压发动机性能变化最大 ,燃速压强指数为 1 0的非壅塞固体火箭冲压发动机的性能基本实现了等空燃比调节。贫氧推进剂的燃速压强指数越高 ,非壅塞固体火箭冲压发动机燃气流量的自适应调节能力越强。  相似文献   

4.
在给定发射初始条件、目标逃逸方式及控制律条件下进行了导弹性能仿真,给出了采用变推力固体火箭发动机的战术导弹最大发射弹目距离和变推力固体火箭发动机二级推力所对应的关系,形成了仿真条件下的变推力发动机控制律,丰富了采用变推力发动机的导弹制导律设计维数,并分析了发动机二级推力调节对弹道设计的影响,对采用变推力固体火箭发动机的导弹弹道优化设计具有一定的指导意义。  相似文献   

5.
本文提出了一种基于固体火箭发动机性能散布分析的固体导弹最大射程评定方法,将系统辨识、性能散布分析和统计分析有机结合,实用性强,对固体导弹试验鉴定技术研究具有重要意义。  相似文献   

6.
本文提出了一种基于固体火箭发动机性能散布分析的固体导弹最大射程评定方法,将系统辨识、性能散布分析和统计分析有机结合,实用性强,对固体导弹试验鉴定技术研究具有重要意义。  相似文献   

7.
研究了非壅塞固体火箭冲压发动机的工作特性。研制出了能量高、燃速高、燃速压强指数高、低压燃烧性能好的铝镁贫氧推进剂配方。采用连管式试验与数值分析相结合的方法 ,对非壅塞固体火箭冲压发动机性能进行了系统的研究  相似文献   

8.
在综合考虑固体火箭发动机设计、轨道设计和总体特性相互作用、相互影响的情况下,建立了捆绑助推器总体/动力/轨道一体化设计优化模型和系统分析模型,并应用遗传算法完成了某大型捆绑助推器6个设计参数的优选。结果表明:本文方法优化设计效果明显,优化所得助推器质量比原方案减轻了17.7%。  相似文献   

9.
为更准确地预测导弹固体火箭发动机贮存寿命,提出将Monte Carlo随机有限元法与RBF神经网络相结合,对固体发动机贮存寿命进行预测。对固体火箭发动机的结构可靠性利用Monte Carlo随机有限元法开展了不确定性分析,以此获得药柱的结构可靠性指标;基于RBF神经网络对固体发动机可靠性下降趋势进行预测,进而预测出导弹固体发动机寿命。  相似文献   

10.
本文介绍了固体火箭推进技术的发展趋势;对于战略导弹发动机,主要是提高发动机性能,使导弹小型化,能在汽车上、火车上或飞机上机动发射,对于防空导弹发动机,主要是发展推力可控技术和无烟推进剂,使导弹能对付高速、高机动的目标,并使发射场和导弹本身不被烟雾暴露;对于运载火箭助推器和小型运载火箭发动机,主要是降低成本和提高可靠性。固体火箭推进技术应用于国民经济建设,也是其发展的一个重要方面。  相似文献   

11.
Energy continues to serve as the bedrock of modern economies and the main driver of modern society. For Africa, the production and supply of energy resources such as crude oil, natural gas, uranium, coal, biomass, biofuels and other renewables are an important source of employment, rents, taxes, royalties and profits. This sector brings in several tens of billions of dollars of revenue annually. The production and delivery of such resources, however, depend on critical infrastructures such as pipelines, refineries, processing plants, terminals, rigs, electrical energy pylons, substations, pump stations, vessels, and tankers. These infrastructures have been attacked by terrorists, insurgents, vandals and saboteurs, all of whom see them as targets against which to register their grievances and extract concessions from the state. This paper is a chronological account of some of the documented incidents of terrorism, insurgency, kidnapping, destruction, sabotage, and human casualties suffered in the oil and gas sectors in Africa between 1999 and 2012. It is based on data extracted from the databases of the RAND Database of World Terrorism Incidents and the University of Maryland's Global Terrorism Database (GTD).  相似文献   

12.
In the Post-Bipolar Era the growing complexity of the military operations requires a new approach for the resolution of international crises. Since the end of the Cold War, peace support operations (PSO) have become the mainstay and principal occupation of most Western armies. At the same time, Italy has been one of the most important actors in such an area. The article focuses on the cooperation between military and civil components (a process called CIMIC) as a key variable in the Italian PSOs. We will analyse in detail the main lessons learned from past military interventions as well as the general context in which new tendencies are taking place. The maintaining of a minimum security frame becomes essential to fulfil activities ‘collateral’ to the mission: reconstructing services and infrastructure, food distribution, water and medication, law and order, de-mining, training of local forces, and supporting local institutions. These are the main tasks to obtain thrust and support from the population.  相似文献   

13.
This article demonstrates the inconsistent and wavering Soviet attitude towards national liberation movements in general and the Palestinian organizations in particular. Until the late 1960s, the Soviets viewed these organizations with suspicion, hesitating to engage in political dialogue with them. However, in the 1970s, political and military events in the region, as well as modifications in the Kremlin's Cold War strategies, led to a general shift towards the Middle East in Soviet foreign policy. Soviet leaders showed increased willingness to provide certain Palestinian organizations with arms with which to conduct terrorist activities against Israeli, pro-Israeli, Jewish and Western targets. The article explores the complex relations between Palestinian organizations and the USSR in the field of international terror. The study also exposes and analyzes the nature and content of Soviet–Palestinian arms dialogues and transactions. It provides clear evidence that Soviet policymakers and other luminaries were fully informed of, and sometimes directly involved in, these transactions and dialogues at the highest levels.  相似文献   

14.
The September 11 global crisis prompted by the attacks on the World Trade Center and the Pentagon raises major questions concerning the nature and trajectory of terrorism in the post-Cold War global order. Hitherto, terrorism has been largely debated by analysts at the level of nation states. Terrorist and insurgent movements have also been largely anchored in nationalist and ethnic power bases even when they have sought to mobilise a transnational ideological appeal on religious or class grounds. There have been a few exceptions to this pattern such as the alliance between the German Baader-Meinhof group and the Japanese Red Army Faction, but even such international alliances as this did not, until at least the 1980s, presage anything like a global terrorist network necessitating a global strategic response. This study examines terrorism and global strategic responses.  相似文献   

15.
This article analyses to what extent the Burmese KNU insurgency made use of external support from states, refugees, and diasporas. Based on extensive fieldwork it is concluded that support from neighbouring states and refugees has for years kept the Karen rebellion alive. Western countries perceived forms of resistance to the illegitimate Burmese regime as just and have therefore played a crucial role in the continuation of conflict in Karen State. It is important that policymakers and donors as well as executing organizations continue to reflect critically on the way they exercise their work.  相似文献   

16.
装备的RMS是装备的重要设计参数,是影响战备完好和保障能力的关键因素.引入GTST-DMLD作为主要建模工具,建立起装备系统的RMS描述模型,以ESD为补充和扩展,对维修过程进行建模.并以GTST-DMLD-ESD模型作为装备RMS仿真的核心,对装备RMS仿真模型的总体框架进行了研究,并对各模块进行了较为详细的探讨.  相似文献   

17.
18.
ABSTRACT

What was the scope of the Bosnian jihadi participation in the war in Syria? Did the Bosnian volunteers tend to join one particular faction? Why did the Bosnian youngsters decide to join the holy war in the Levant? Was this an organized and hierarchical process or was this a grassroots movement? Last, were all the Salafis in Bosnia supportive of this dynamic or did this process cause internal frictions? These are some of the questions that this research will try to answer.  相似文献   

19.
The UK’s interrogation operations during the conflict in Iraq (2003–2008) are often portrayed by the media as involving significant amounts of mistreatment. This article demonstrates that these practices are not necessarily representative of the UK’s interrogation operations across this conflict. In doing so it contributes to the limited literature on the practice of interrogation and on the UK’s combat operations in Iraq. The UK’s interrogation capability, and therefore its intelligence-gathering capability, is shown to have rested primarily with the military’s Joint Forward Interrogation Team (JFIT). The JFIT suffered from limitations to the number, training and experience of its interrogators and interpreters. It is argued that maintaining a permanent, higher level of preparedness for interrogation by the British armed forces is desirable.  相似文献   

20.
ABSTRACT

While the study of organised violence is considered essential to understanding the history of the West, and accordingly imbued with various layers of meaning and remembrance, war is widely regarded as inimical to the modern nation in Africa and stable development more broadly. Using examples drawn from primarily from East Africa, this paper considers the ways in which warfare in the deeper (‘precolonial’) past has been framed and envisioned in recent decades, in particular by governments whose own roots lie in revolutionary armed struggle and who began life as guerrilla movements. While in some cases particular elements of the deeper past were indeed mobilised in pursuit of contemporary political goals, in many other scenarios histories of precolonial violence were beheld as problematic and unworthy of remembrance. This paper highlights the paradox and ambiguity which has attended the memory of key aspects of Africa’s deeper past.  相似文献   

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