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1.
低轨单星对自由段弹道的估计是天基预警系统需解决的关键技术之一.建立了低轨预警卫星对自由段弹道的观测模型,针对极大似然估计批处理算法的大运算量问题,给出了一种多项式逼近算法,由观测数据的逼近多项式在一些特定采样点的值形成伪观测数据,以伪观测数据代替原观测数据进行弹道估计.仿真表明,精度与极大似然估计相当,运算量显著降低.  相似文献   

2.
为了对增程弹道修正弹进行偏差计算、形成修正指令,需要对测量的一段弹道参数进行辨识,目前的辨识算法都是基于相对地球静止射面坐标系的,但是,舰炮发射修正弹以后舰艇继续机动,跟踪雷达随之运动和摇摆。针对舰艇作战环境的特点,建立了舰炮发射增程弹道修正弹测量弹道坐标到射面坐标系的转换模型,并采用基于弹道方程的滤波方法对转换后的坐标数据进行了仿真。建立的模型可以为舰炮发射修正弹的火控软件研制提供参考。  相似文献   

3.
弹道目标跟踪问题中动态方程与观测方程皆为非线性,影响跟踪精度。使用最优线性无偏估计方法可以有效地解决观测的非线性问题,而蒙特卡罗滤波方法适用于目标状态的非线性估计。将快速高斯粒子滤波与最优线性估计方法作了有机结合,通过对典型的弹道目标跟踪模型进行仿真,发现新算法在精度与实时性上优于粒子滤波。  相似文献   

4.
由于工作原理不同,舰炮使用传统无控弹试射方法不适用于一维弹道修正弹。分析了舰炮使用一维弹道修正弹射击误差构成和试射的必要性,提出了一维弹道修正弹校正射击诸元误差和预测误差试射新方法。首先通过分析对海射击以实际观测弹着水柱与提前点偏差作为发射诸元误差的精度,以及以预测弹着落点与实际观测弹着水柱偏差作为预测误差的精度,提出了求取诸元误差和预测误差的方法,论证了试射发数;然后从距离上和方向上校正诸元误差和预测误差。假设各误差值,通过仿真计算表明,按新方法试射能够显著提高射击精度。  相似文献   

5.
由于工作原理不同,传统无控弹射击校正方法不适用于一维弹道修正弹。分析了舰炮使用一维弹道修正弹射击误差构成和射击观测特点,提出一维弹道修正弹射击校正新方法,首先通过修正机构不工作,利用观测弹着点相对预测弹着点偏差平均值校正火控设备预测弹着点误差;然后利用修正弹正常工作时观测弹着点相对目标(或提前点)偏差平均值校正修正机构误差。假设各误差值,通过解弹道方程仿真计算表明,按新方法射击校正能够显著提高射击精度。  相似文献   

6.
舰炮防空是水面舰艇自防御的重要手段之一.文章围绕可视化和虚拟现实技术,分析了舰炮防空战法研究的内容,给出了舰炮防空战法可视化的方法,重点探讨了其中的防空弹道仿真、反舰导弹弹道仿真、海浪水文气象环境仿真、战场焰火和爆炸效果仿真及舰炮防空战法仿真中实时碰撞检测的基本方法和优化技术,提出了解决这些问题的主要方法,并在PC机上进行了实现.最后给出了舰炮防空战法的可视化结果.  相似文献   

7.
为利用仿真模型在有限校射样本的条件下对校射补偿量进行合理估计,对考虑仿真可信度的舰炮虚拟校射方法进行了研究。对自适应加权贝叶斯估计方法进行了研究,一方面对仿真先验可信度的计算方法进行了分析,另一方面对考虑先验可信度的自适应加权贝叶斯估计算法进行了研究。在此基础上,结合舰炮虚拟校射的原理和需求,建立了舰炮虚拟校射诸元误差自适应加权贝叶斯估计模型。仿真验证表明:自适应加权贝叶斯估计方法能够利用试验数据对仿真模型的可信度进行有效验证并进一步实现对目标分布的有效估计;所设计的校射方法能够综合利用仿真模型和校射样本的优势,实现对诸元误差的合理估计,达到有效提高校射精度的目的。  相似文献   

8.
针对国外基于GPS定位系统的弹道修正弹及相关火控技术的发展情况,分析和研究了弹道修正弹的控制特点和火控原理,提出了在基于卫星定位的弹道修正弹中应用舰炮火控成熟技术,完成弹道参数计算、弹道外推预测和弹道修正控制等功能的设想,可为舰炮火控技术在基于卫星定位的弹道修正弹中的应用提供技术参考。  相似文献   

9.
一维弹道修正弹是近年来兵器领域新研制的一种低成本信息化弹药,目前对其校射方法尚未有成熟的标准。为此,在分析一维弹道修正弹对岸射击工作原理、计算有无控弹试射的基础上,提出舰炮武器系统使用有控一维弹道修正弹的校射新方法,并确定了校射的组数和发数。分别对使用新方法前后的射击效能进行了数值仿真,结果表明本方法能极大地提高舰炮武器系统的射击效能。所提方法对舰炮武器作战效能的提高具有较强的理论价值和一定的参考意义。  相似文献   

10.
自由飞行段弹道估计方法   总被引:1,自引:0,他引:1       下载免费PDF全文
主要研究空间预警系统利用星载红外传感器的视线测量估计弹道导弹自由飞行段弹道的问题。针对目标运动的弱可观测性 ,提出了位置与速度依次滤波的改进Gauss -Newton方法 ,解决了自由段弹道的最大似然估计问题 ,利用MonteCarlo仿真实验验证了估计方法的有效性 ,并对估计误差进行了分析。  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 Soviet Union was able to develop a large military-industrial complex and become the world's second superpower despite deficiencies in its centrally planned economy because defence was given high priority status and special planning, rationing and administrative mechanisms were used to attain national security objectives. However, in the period 1976-85 the effectiveness of priority protection diminished and defence institutions experienced more of the problems typical of the shortage economic system. The heavy defence burden also created growing difficulties for the civilian economy. The attempts by the Gorbachev government to reform the defence sector and improve defence-economic relationships during perestroika (1985-91) uniformly failed. For most of the transition period, the Russian military-industrial complex has been adversely affected by its low priority status, cuts in defence spending, instability of the hybrid politico-economic system, and negative growth of the economy. The armed forces and defence industry have been reduced in size and their outputs of military services and equipment have fallen to low levels. Nevertheless, the Russian armed forces still have over one million troops, significant stocks of sophisticated conventional weapons, and a large nuclear arsenal. The government of President Putin has raised the priority of the defence sector, increased real defence spending, and adopted ambitious plans to revive Russian military power. It is likely, though, that tight resource constraints will hamper efforts to reform the armed forces and to upgrade weapons. By 2010 Russia will be an important, but not dominant, military power in Eurasia.  相似文献   

20.
The collapse of the Soviet Union precipitated the massive expansion of drug use and trade in Russia. The country now has one of the largest populations of injecting drug users in the world and has become the largest single-country market for Afghan heroin. In 2003 the Federal Service for the Control of the Drugs Trade was created to coordinate a comprehensive counternarcotics strategy appropriate to the scale of this threat. The service continues to face a number of challenges in its early stages of development. However, it has made considerable advances in improving responses to large-scale organised crime and in building international cooperation.  相似文献   

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