基于DELMIA的飞机货物可装载性平台设计

现阶段国内航空货运时间周期中95%要用在航空货运站,尤其是收货时对于特殊尺寸的货物能否装入窄体客机货舱的判断耗时较多。为了解决这一问题,在Visual Studio环境下,利用基于V5 Automation的DELMIA软件二次开发技术,建立了数据库,设计了货物可装载性判别应用平台,利用折半查找法实现货物数据与货舱装载...     

民用航空器研制中制造符合性声明的使用

制造符合性声明是申请人签署后,提交局方进行制造符合性检查的重要文件。在型号研制阶段,申请人签署制造符合性声明,向局方表明符合设计资料,局方进行检查并确定是否安全可用;在依据型号合格证进行生产阶段,申请人签署制造符合性声明,向局方表明符合设计资料并处于安全可用状态,局方进行检查得到确认后签发适航批准证书;在获得生产批准后,申请人无需提交制造符合性声明,即可获得局方签发的适航批准证书。通过对中国民用航空局、美国联邦航空局和欧洲航空安全局适航规章的要求进行比较,对制造符合性声明在不同阶段的作用进行研究和探讨。     

发动机某型号节流圈的切削加工

某型号节流圈,其结构特点是壁薄,壁厚仅2.5mm,轴向尺寸小,精度高,刚性差;加工难点为装夹时容易变形,尺寸精度难以保证。通过设计、制作专用夹具,优化加工参数,解决了这一加工难题。这样既保证了产品质量,降低了加工难度又显著提高了生产效率。     

APC—2／AS4热塑性带材火焰辅助缠绕研究——火焰温度对成形质量的影响

通过对ＡＰＣ－２／ＡＳ４带材火焰辅助缠绕过程的研究，分析了工艺条件对制件成形质量的影响和制件的断面显微特征，认为火焰辅助缠绕制件的孔隙主要是由于基体和纤维的降解失重产生的，而不是空气夹杂产生的。     

用户星中继终端在轨应用策略

在介绍在轨用户星中继终端的分类、功能和使用现状的基础上,重点对用户星中继终端多约束条件进行了梳理分析。为缓解常态化应急测控带来的资源紧张矛盾,提出了用户星中继终端在轨应用策略,即Ka/S模式下影随测控,小S模式下定时捕获。针对Ka+小S模式下实现影随测控的可行性问题,利用STK(Satellite Tool Kit,卫星开发工具包)软件进行了仿真计算分析,结果表明:为实现影随测控,满足测控快速响应需要,要求星载S频段中继测控天线对中继卫星的覆盖范围,应大于星载中继数传天线对中继卫星的覆盖范围。     

未来机载雷达可靠性和寿命周期成本的研究

目前还没有对未来机载雷达系统的可靠性和维修性的要求充分量化，但已经认识到需要对现有可靠性和可用性的标准进行较大的改进。     

氙离子火箭发动机配电调节分系统的时序控制

从理论和实验两个方面对直径９ｃｍ氙离子火箭发动机配电及控制系统进行了研究，并设计出以８０３１单片机为核心组成的微机实时监控系统．为了减少加热电源和阴极本身的热冲击，阴极电源分五档位制；考虑到束流电源的瞬变特性，为避免对发动机和电源产生不利的影响，采用了慢起动特性；对子在发动机工作过程中有时出现的过载、灭弧、高压打火或短路等现象，能及时发现并作出实时处理和控制。     

群决策的统计处理方法——序数法

本文给出了一种目标无法量化时的群决策方法，通过一系列的统计处理可以方便地将群中成员的偏好集结为群的偏好，最终对气有可行方案给出体现群体意志的排序来。     

Vestibular function in the space environment

Adaptation to the weightless state and readaptation after space flight to the 1-G environment on the ground are accompanied by various transitory symptoms of vestibular instability, kinetosis, and illusory sensations. Aside from the problem of how to treat and if possible prevent such symptoms, they offer a clue to a better understanding of normal vestibular functions. Weightlessness is a powerful new "tool" of vestibular research. Graybiel reported as early as 1952 that human subjects observed the illusion that a real target and the visual afterimage seemed to raise in the visual field during centrifugation when the subjects were looking toward the axis of rotation (oculogravic illusion). In aircraft parabolic-flight weightlessness, human subjects observed that fixed real targets appeared to have moved downward while visual afterimages appeared to have moved upward (oculoagravic illusion). It can be shown by electronystagmography as well as by a method employing double afterimages that part of this illusion is caused by eye movements that are triggered by the changing input from the otolith system. Another part of the illusion is based on a change of the subjective horizontal and must be caused by convergence of vestibular and visual impulses "behind" the eyes. This part was measured independently of the first one by using a new method. Eye movements could be prevented during these experiments by optical fixation with the right eye on a target at the end of a 24-in. long tube which was rigidly attached parallel to the longitudinal axis of an aircraft. At the same time the subject tried to line up a shorter tube, which was pivoting around his left eye, with the subjective horizon.     

Hydroelectrolytic and hormonal modifications related to prolonged bedrest in antiorthostatic position

The effects of prolonged bedrest in antiorthostatic position (-4 degrees head down) on electrolyte balance were studied in 4 young volunteers. An increase was noted in sodium excretion during the first 4 days. Plasma renin activity and plasma aldosterone varied in parallel manner during the same period. Potassium balance and creatinine clearance were not significantly modified. In light of these data we feel that prolonged bedrest in antiorthostatic position constitutes an effective way to simulate on earth metabolic and hormonal modifications occurring in man under weightlessness conditions.