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691.
针对一种基于DSP+FPGA+MCU多处理器计算机平台的弹载组合导航系统设计了精确有效的信息同步的方法,采用GPS接收机提供的1PPS脉冲和MCU提供的脉冲信号实现GPS和SINS信号时间上的同步,采用杆臂校正算法完成了GPS和SINS测量信号空间上的同步.由于系统噪声难于准确统计,因此采用自适应卡尔曼滤波算法进行数据融合.最后对系统进行了跑车试验,试验结果表明系统所采用的方法具有较好的效果.  相似文献   
692.
海战场信息对抗仿真系统为海军信息作战理论与战法研究、信息作战装备的作战效果模拟提供了一种新的途径。在对体系对抗仿真的体系结构分析的基础上,给出了海战场信息对抗仿真系统的设计思想,提出了系统的功能和总体框架,并对其中的一些关键技术进行了分析和探讨。  相似文献   
693.
海战场信息对抗仿真系统为海军信息作战理论与战法研究、信息作战装备的作战效果模拟提供了一种新的途径.在对体系对抗仿真的体系结构分析的基础上,给出了海战场信息对抗仿真系统的设计思想,提出了系统的功能和总体框架,并对其中的一些关键技术进行了分析和探讨.  相似文献   
694.
针对C4ISR组织结构的复杂特点,运用社会网络分析概念分析军事C4ISR(指挥、控制、通信、计算机、情报、监视和侦察)组织结构,旨在对军事组织结构中的C4ISR的效能给出一种定量分析的方法.具体讲,就是描述了FINC(力量、情报、网络和指挥控制)方法,给出了大量的基本运算法则来比较和定量分析C4ISR组织结构的组织网络,便于更全面地分析评估不同组织结构的费效比,并将其应用于一个想定的C4ISR组织结构中.  相似文献   
695.
在已建立的应力波传播模型和研究弹、板间作用力所获结果的基础上,为分析复合板应力的变化,对复合板弹板碰撞承受的应力进行了简化处理,根据应力波传播特性,确定了复合板内能量集中区域,研究了应力波在复合板巾的传播和能耗,并讨论了应力波对陶瓷的作用。通过近似计算,发现烧蚀消耗的弹丸动能较大,在复合板中,Al板的塑性变形吸收了19%的弹丸动能。  相似文献   
696.
India and China both have powerful spy networks; completely different in their approaches to espionage; both effective against their perceived enemies. China focuses first on internal threats, on Taiwan and Hong Kong, and then the US and Japan. India’s defense policy focuses on Pakistan and internal terrorist threats, and then on China. In reality, however, when it comes to spying on each other, both China and India suffer from incompetence and apathy – which endangers both their own security and regional stability. This article looks at how they spy on each other, and asks why and how they need to improve. The narrative also touches upon some of the individuals who are waging the spy war, from India’s wily spymaster Ajit Doval down to junior Chinese agents such as Wang Qing and Pema Tsering. The two countries are not friends. They have the largest territorial dispute in the world on their hands, covering an area the size of North Korea, and they have large armies facing each other along 4000 kilometers of frontier. But they also lay claim to the world’s two oldest and richest civilizations, with a rich history of exchange, and now with a combined population of 2.6 billion people and more than a quarter of the world’s economic output. If they cooperated, they could solve many of the world’s problems; but if they lurch into conflict, the potential consequences are terrifying to contemplate. Unfortunately, despite their geographical closeness, they do not know much about each other. They have few cultural interchanges, little diplomacy, few trade missions. They do not watch each other’s films, read each other’s books or listen to each other’s music. Chinese tourists would rather fly to New Zealand for their holidays than cross the border to India, and Indian students would rather study in Europe than China. China and India are neighbors that barely talk to each other. Most significantly, they do not spy on each competently. For countries that do not interact socially, defensive understanding is important for security – but China prefers the glamor of facing up to its Pacific and other maritime rivals such as the US and Japan. India, for its part, does talk a great deal about the China threat, but its resources and expertise are wrapped up in controlling its security threat from Pakistan and the Islamic world. When China and India do try to spy on each other, it is often without the benefit of a long-term focus or understanding. India has some very skilled operatives within the Research and Analysis Wing, but few that specialize in China. China has an enormous pool of resources spread across several government departments, including the Ministry of Public Security, and also has extensive facilities and manpower in the Joint Staff Department of the Central Military Commission (the JSD) and the new Strategic Support Force (the SSF). However, China’s intelligence services generally behave as if India is not worth spying on. Given that the two countries do not have the cultural or political machinery in place to understand each other, espionage and intelligence gathering is vital to ensure that miscalculations do not take place. This has been apparent over the last few years in stand-offs in the Himalaya, as well as top-level suspicions on each side about a variety of subjects including terrorism, covert operations in Sri Lanka and Burma, and the two countries’ nuclear weapons programs. Both countries do occasionally make efforts in espionage against each other, especially during sensitive periods such as the mountain stand-offs of 2014 and 2013 and during policy developments in nuclear warfare. In this article the author looks at actual spying incidents between the two countries, their methodologies, their staff, their technical capabilities, and how the act of spying, which is usually viewed as intrinsically adversarial, can be a force for good. The article relies on interviews with actual participants in intelligence from both countries as well as extensive use of contemporary online sources, and secondary analysis by both military and academic experts from China, India and NATO countries.  相似文献   
697.
现阶段,国内外应急事件时有发生,如何快速有效地实施应急指挥控制是处置社会公共安全突发事件的核心要求之一。因此,以OODA模型为基础提出了一种基于敏捷性指标的应急指挥控制过程模型和一种基于Lotka?Volterra模型的度量指挥控制敏捷性的数学计算方法,并以地铁突发爆炸事故为背景,对应急指挥控制的敏捷性与指挥控制效果进行了仿真分析和对比。  相似文献   
698.
针对舰载火控系统通信需求,提出基于DDS的舰载火控体系结构,实现了系统松耦合,同时满足了实时性要求。通过发布订阅服务的设计,基于默认QoS策略,分别使用内置数据类型和自定义数据类型实现舰载火控系统的发布订阅功能。通过可靠性QoS策略的配置分析其对系统实时性和可靠性的影响。测试结果表明,DDS在舰载火控系统中有广阔的应用前景。  相似文献   
699.
喷嘴是产生高压水射流的关键部件,其结构形式对射流动力学性能有很大影响。以圆柱形喷嘴为对象,进行喷嘴结构对高压水射流的影响分析及结构参数优化设计。采用两相流计算流体力学模型进行喷嘴内外的射流流场分析。为节省计算资源,在优化设计时引入Kriging代理模型替代计算流体力学模型。分别采用改进的非劣分类遗传算法和基于分解的多目标进化算法进行单目标和多目标优化设计。研究结果表明:直线型喷嘴总体性能较优,凹型喷嘴的次之,凸型喷嘴性能最差。以直线型喷嘴为设计对象,以射流初始段长度和流量为目标,得到了单目标和多目标优化设计结果。单目标优化时,两个指标较基准外形分别提高14.71%和27.56%。多目标优化时,优化得到的半锥角处于[15.4°,89.8°]区间内。运用代理模型和进化算法的全局优化方法在进行喷嘴的优化设计时是有效的。  相似文献   
700.
航天器姿态控制系统需要特殊的运行环境,在地面很难考核,这给系统可靠性带来一定的风险。针对微纳卫星的特点,设计并研制了一套面向微纳卫星的姿态确定与控制半实物仿真系统。该系统通过数字化模型模拟卫星姿态轨道运动、敏感器模型产生敏感器测量数据、执行器模型生成控制力矩、敏感器模拟器实现通信协议,最终实现姿态控制系统的全系统仿真。这套系统可以接入卫星控制系统回路,实现对姿控系统软件、硬件的考核,同时验证算法的性能。基于该系统,对天拓三号卫星姿控系统进行地面半实物仿真,并对比在轨试验数据,结果表明系统设计合理,仿真结果可信。  相似文献   
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