基于联合k/n(G)模型的DIMA系统可靠性建模与分析

针对分布式综合模块化航空电子（DIMA）系统的动态重构特性,分析了动态重构策略及重构过程,构建了面向DIMA系统的联合k/n（G）可靠性模型。以驻留于DIMA系统的综合显示功能为例进行了实验分析,讨论了系统重构过程可靠度与时间变化关系,给出了利用一般k/n（G）可靠性模型建模的可靠度变化曲线,通过对比分析验证了联合k/n（G）模型的适用性和合理性;通过参数敏感性分析,观察不同模块配置参数对系统可靠度的影响,得出相关结论,为提高DIMA系统动态重构过程的可靠性和优化资源配置提供指导。     

多边比较中G-K系统的存在性和唯一性研究

在进行国际比较问题研究中,人们经常使用著名的G-K系统方法,然而关于该方法是否存在唯一的正解一直是经济学家们争论的问题.本文在总结前人研究成果的基础上,对该问题进行了深入、广泛地探讨,获得了关于购买力平价国际多边比较中G-K方法的唯一正解的存在性和唯一性若干个等价条件,并指出了Prasada的文献中论证该问题的错误.另外,本文还研究了G-K系统的唯一正解的自动生成问题,并对此作出了经济学解释.      

五坐标数控加工刀位轨迹及其干涉检查的算法研究

CAD/CAM系统中复杂曲面数控加工刀轨的计算能力在工业中有极其重要的作用。介绍一种复杂曲面五坐标加工轨迹生成及干涉处理算法,即把曲面用小三角片离散逼近,并用连通图建立所有三角片之间的拓扑关系,在此基础上生成刀轨,并进行干涉检查及刀位修正。     

Pc5 Oscillation Analysis by the Satellite and Ground-Based Data

Large amplitude Pc5 event was observed in the space and on ground on August 3, 2001, about three hours after contact of the strong discontinuity in the solar wind with the magnetosphere according to data from ACE and Wind satellites. The Pc5 amplitude was as high as 15 nT in the tail of magnetosphere and about 5 nT at the ground based stations. In the magnetosphere Pc5 waves were observed by Cluster and Polar satellites, which occupied positions in the morning part of the near tail at the close field lines but were parted by distance of 11.5 Re, mainly along the x-axis of the GSM coordinate system. Both compressional and transverse components of the Pc5 wave activity were observed in the space, with the transverse component having the larger amplitude. Time delay between the Cluster and Polar satellites was about 8 minutes, which could be interpreted as a wave propagation from the geomagnetic tail to the Earth with the 150 km/s group velocity. The ground-based Pc5 activity was analysed by using data from the Image magnetometer network. Doubtless demonstrations of a field line resonant structure were found in variations of amplitude and polarization with latitude. Finnish chain of search coil magnetometers observed modulated Pc1 emission simultaneously with the Pc5 wave train. A possibility of non-linear impact of Pc5 wave energy on the plasma and waves in the magnetosphere is discussed.     

Orbital corrections by a single-input impulsive control applied along the geomagnetic field

This paper examines the possibility of regular orbital corrections for a satellite controlled by an impulsive force applied along the induction vector of the local geomagnetic field. The main purpose of the correcting considered in the paper is to eliminate the drift in secular variation of the relative orbital parameters over the orbital period. The obtained results are applied to the formation flying problem. The developed method is tested using numerical simulation.     

四唑类盐的制备及其在固体推进剂中的应用初探

合成了5-苯基四唑、5-亚甲基二四唑，并通过元素分析及质谱方法对其进行了分析鉴定，制备了其铜、铅、锶盐；对3种金属盐在改性双基推进剂配方中的应用进行了探索性研究。初步研究表明，四唑类的金属盐类可以作为复合改性双基推进剂(CMDB)的含能燃烧催化剂。     

3,4-双(3',5'-二硝基苯-1'-基)氧化呋咱的热 行为和非等温热分解动力学研究

为了评价含能材料3,4-双(3',5 '-二硝基苯-l'-基)氧化呋咱(BDPF)的热稳定性和安全性,采用DSC、PDSC和'G/DTG方法对其进行了热行为及非等温热分解动力学研究.通过Kissinger和Ozawa's法得到常压下热分解反应的动力学参数(Ea和A)为180.46 kJ·mol-1和1015.29 s-...     

3,6-双(1-氢-1,2,3,4-四唑-5-氨基)-1,2,4,5-四嗪-1,4-丁二胺盐的制备和热分解动力学及热安全性

利用3,6-双(1-氢-1,2,3,4-四唑-5-氨基)-1,2,4,5-四嗪(BTATz)和1,4-丁二胺,在DMSO中合成出了标题化合物。采用元素分析和红外光谱分析,测定了其结构。用DSC和TG/DTG热分析仪,对标题化合物进行了热分解行为及热分解动力学研究。结果表明,化合物的热分解过程只有一个放热阶段,该阶段的非等温热分解反应动力学方程的活化能和指前因子分别为92.95 kJ/mol和1016.58s-1。采用MicroDSCⅢ量热仪中的连续比定压热容测定模式,测定了化合物的比定压热容,比定压热容随温度呈现二次方关系,且298.15 K下的标准摩尔热容为443.22 J/(mol.K)。计算得到化合物的自加速分解温度(TSADT)、热爆炸临界温度(Tb)和绝热至爆时间分别为521.55、536.73 K和36.97 s。     

浅析工业工程在质量QC小组活动中的运用

综述现代工业工程主要特点、基本工作方法及其在QC小组活动中的运用,提出了质量管理与工业工程有机结合,能够控制成本并使工作方法达到最优化。介绍了一个工业工程在QC小组活动中的运用实例。     

CFM56-5B 发动机VBV故障引起的EGT超温故障分析

从可变放气活门系统(VBV)的组成和工作原理入手,通过对系统部件和关联部件工作分析,结合维护过程的故障历史,指出了故障的排除方法和维护提示.