热真空条件下工作的电气电缆载流量计算与试验

高空制导飞行器从母舱释放后,制导舱与仪器舱之间部分电气电缆处于热真空条件下工作。对此种特定条件下的电缆进行了载流量计算。理论计算表明,给定的电缆设计满足在热真空条件下正常工作要求。最后简略介绍了载流量试验。     

基于效能的舰艇电子对抗训练效果评估方法

摘 要：为解决舰艇电子对抗专业训练缺乏统一评估标准与方法体系等实际评估难题;采用系统分析方法结合舰艇电子对抗专业训练实际;研究提出了基于“任务要求分解”的作战效能量化指标体系构建方法、训练效果表达方法及实用评估指标体系、定量指标评估模型、评估标准等舰艇电子对抗训练效果评估方法体系;能够满足专业训练效果评估所需,对其它专业军事训练效果评估工作亦具有借鉴意义。     

结合实时数据产品与北斗短报文的厘米级海洋精密相对定位

针对远海精密定位的广泛需求和传统精密定位服务费用昂贵的问题,提出利用北斗短报文设备传输导航观测数据,结合实时服务数据产品,以实现海洋的低成本厘米级精密相对定位。为了克服短报文传输频率低的缺点,采用融合空间相对定位和精密单点定位两种技术来加密分钟间隔以外的坐标,避免了传统时间基线法加密坐标存在的误差累积现象。分别基于静态和动态海洋观测数据进行仿真实验,结果表明,新方法无论在水平方向还是垂直方向上,都可以实现厘米级定位,且对时间间隔不敏感。     

节点实时性能自适应的集群资源分配算法

由于配置和所运行作业的不同,集群各节点的实时性能差异较大。为提高集群性能,提出节点实时性能自适应的集群资源分配算法 (node real-time performance adaptive cluster resource scheduling algorithm,NPARSA)。节点实时性能用其配置(CPU核数及速度、内存容量、磁盘容量)和实时状态参数(CPU、内存和磁盘的剩余数量及磁盘读写速度)表示。NPARSA根据作业类型自主选择节点性能评价指标的权值,实现节点实时性能对于作业类型的自适应。实时性能最优的节点分配给作业。虚拟机实验和物理集群实验表明,与Spark默认资源分配算法、没有考虑作业类型与节点匹配的算法、使用作业和节点匹配差异程度作为资源分配依据的算法相比,NPARSA能更有效地缩短作业执行时间、提高集群性能。     

Experiment and simulation of launching process of a small-diameter steel cartridge case

In order to explore the rules of the deformation force during the launching of a small-diameter steel cartridge, the semi-closed bomb test method is used to test the greatest strains on chamber outer wall under the different chamber pressures. The pressure curves of cartridge chamber are measured in experiment, and the tensile test data of cartridge are loaded into the numerical calculation to compare with the experimental data. The conclusion was obtained that the calculated results match better with the experimental results by considering strain rate bilinear kinematic hardening material constitutive model. The forces on the various parts of the cartridge during launching and their deformation rules are achieved, in which the equivalent plastic strain decreases and the cylinder ring withstands the maximum equivalent stress when the cartridge case clings to the bore from the mouth to the bottom.     

On the continued acceleration of bomb casing fragments following casing fracture

It has been said that, once a bomb casing has fractured, “detonation gases will then stream around the fragments or bypass them, and the acceleration process stops there.” However, while apparently copious gas flow through casing fractures indicates some pressure release, it is also an indication of significant gas drive pressure, post casing fracture. This paper shows two approaches to the problem of calculating the actual loss of drive. One presents first-order analytical calculations, in cylindrical geometry, of pressure loss to the inside surface of a fractured casing. The second shows the modelling of a selected example in the CTH code. Both approaches reveal that gas escape, while occurring at its own sound-speed relative to the adjacent casing fragments, has to compete with rapid radial expansion of the casing. Together with some historic experiments now publicly available, our calculations indicate that post-fracture casing fragment acceleration is, for most systems, unlikely to be reduced significantly.     

嵌入式实时操作系统性能测试方法

为综合评价操作系统能否满足使用要求,研究了一种定量测试嵌入式实时操作系统功能和性能的方法,提出了具体的测试项目、测试环境和测试用例的要点,给出一种基于外部注入的功能测试、性能测试、应用测试方法及具体实现。测试结果证明,该方法对提高软件质量,缩短研制周期,增强可维护性等方面有显著效果。     

反舰导弹纯方位发射捕捉概率计算方法

反舰导弹的纯方位发射对目标信息要求不高,在目标信息的探测越来越艰难的今天,是反舰导弹较为重要的一种发射方式,也将会成为未来海战场上常用的作战方式.介绍了反舰导弹捕捉概率的计算方法和传统纯方位发射的捕捉概率的计算方法,并从分析反舰导弹捕捉概率的计算模型和影响因素出发,指出传统的反舰导弹纯方位发射的捕捉概率计算模型存在不足,并给出了修正后的计算模型.     

动态飞行仿真中人体六自由度模型研究

应用多体系动力学方法,结合飞行力学,给出了动态飞行仿真中飞行员的六自由度数学模型,并将其应用在动态飞行仿真建模中,分析结果表明这种数学模型是可行的。     

一种快速实时烟雾仿真方法

在导弹发射、飞行实时仿真系统中,对导弹尾部烟雾的仿真是影响可视化仿真系统真实感和实时性的重要因素。运用粒子系统的方法,对系统中导弹尾部的烟雾进行了仿真,提出了合适的粒子产生、运动、消灭和形状模型,并在系统中得以实现,取得了较好的效果。