一个新的研究领域——演化硬件

演化硬件的概念最初是由HugodeGaris于1992年提出的。硬件演化的目的在于使硬件系统能够像生物一样改变其自身的结构以适应环境的变化。本文首先给出演化硬件的定义,继而介绍演化硬件的物质基础──可编程专用集成电路和演化硬件的理论基础──演化算法。进而研究实现硬件演化的方法,最后讨论演化硬件的发展前景。     

Euler方程数值模拟绕悬停旋翼桨叶的流动

本研究应用格心格式有限体积龙格－库塔时间推进法求解三维欧拉方程,模拟绕旋翼桨叶的流动,民流的作用通过自由尾流分析来求解局部的诱导下洗速度以修正翼型攻角,选择Ｏ－Ｈ型式生成绕桨叶贴体的弦向和展向网格,通过算为进一步寻求有效的Ｅｕｌｅｒ或ＮＳ方程数值解积累了经验。     

可靠性维修性保障性效能模型研究

因素,提出了可靠性维修性保障性效能的概念,定义了进行可靠性维修性保障性综合设计分析的一个新的参数RMS效能E_RMS,推导了在执行任务期间可修复和不可修复2类典型系统的E_RMS表达式,给出了利用参数E_RMS进行可靠性维修性保障性综合设计分析的步骤.      

Analysis and control of the compaction force in the composite prepreg tape winding process for rocket motor nozzles

In the process of composite prepreg tape winding, the compaction force could influence the quality of winding products. According to the analysis and experiments, during the winding process of a rocket motor nozzle aft exit cone with a winding angle, there would be an error between the deposition speed of tape layers and the feeding speed of the compaction roller, which could influence the compaction force. Both a lack of compaction and overcompaction related to the feed-ing of the compaction roller could result in defects of winding nozzles. Thus, a flexible winding sys-tem has been developed for rocket motor nozzle winding. In the system, feeding of the compaction roller could be adjusted in real time to achieve an invariable compaction force. According to exper-iments, the force deformation model of the winding tape is a time-varying system. Thus, a forgetting factor recursive least square based parameter estimation proportional-integral-differential (PID) controller has been developed, which could estimate the time-varying parameter and control the compaction force by adjusting the feeding of the compaction roller during the winding process. According to the experimental results, a winding nozzle with fewer voids and a smooth surface could be wounded by the invariable compaction force in the flexible winding system.     

湿喷丸处理Ti-6Al-4V合金微动磨损行为影响

采用湿喷丸技术对Ti-6Al-4V合金进行表面强化处理,研究了部分滑移、混合滑移和完全滑移等不同状态下钛合金样品的微动磨损行为,从微动状态角度探讨喷丸强化对钛合金微动磨损行为的影响规律。试验结果显示,喷丸处理对于完全滑移状态下Ti-6Al-4V合金的微动磨损行为影响较小;而在混合滑移状态时,喷丸处理使得微动磨痕的塑性变形积累区消失,有效抑制局部疲劳损伤造成的微裂纹萌生。这是因为喷丸引入加工硬化作用使材料表层局部强度提高,进而改善局部疲劳损伤。     

The Juno Radiation Monitoring (RM) Investigation

The Radiation Monitoring Investigation of the Juno Mission will actively retrieve and analyze the noise signatures from penetrating radiation in the images of Juno’s star cameras and science instruments at Jupiter. The investigation’s objective is to profile Jupiter’s \(>10\mbox{-MeV}\) electron environment in regions of the Jovian magnetosphere which today are still largely unexplored. This paper discusses the primary instruments on Juno which contribute to the investigation’s data suite, the measurements of camera noise from penetrating particles, spectral sensitivities and measurement ranges of the instruments, calibrations performed prior to Juno’s first science orbit, and how the measurements may be used to infer the external relativistic electron environment.     

关于电磁干扰环境构建问题的思考

对电磁干扰环境进行逼真构建是武器装备开展抗干扰试验的基础,通过分析防空反导武器实战中面临的典型电磁干扰环境,建立一套可操作的试验电磁干扰环境构建方法,对防空反导武器的研制、部队训练与演习等具有重大意义.分析了国外电磁干扰环境构建的研究现状,提出了基于干扰场景、干扰技术和干扰战术的等效构建方法.     

加速度计加速退化机理一致性边界确定方法

以加速退化模型——Arrhenius模型为研究对象,发现加速度计在加速试验过程中,保持加速机理不变的应力与退化轨迹斜率存在密切关系.通过针对退化轨迹模型分别为一次函数、指数函数和幂函数三种常见情况,从激活能不变角度推导出保证加速度计加速机理不变的应力-斜率公式,然后基于退化轨迹斜率区间检验提出了一种加速机理一致性条件确定方法,最后根据加速度计恒定高温标度因数稳定性退化仿真试验数据,准确得到了保持加速度计标度因数稳定性退化机理一致的应力边界,验证了该方法的可行性.     

平均维修保障等待时间的计算方法

阐述了装备保障系统维修保障等待时间的概念内涵,分析了研制阶段保障方案的设计过程中维修保障等待时间的影响因素,以研制阶段保障分析的结果为输入,运用概率论和矩阵论给出了平均维修保障等待时间的计算方法,为研制阶段保障系统及时性的分析和评价提供依据.给出一个算例,验证了计算方法的可行性与合理性.