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排序方式: 共有299条查询结果,搜索用时 31 毫秒
121.
统计了原中国北方航空公司7架MD-82型飞机的腐蚀损伤情况。就相对湿度、空气中含盐量、工业大气和空运海鲜产品4个因素,分析了各因素对MD-82型飞机腐蚀损伤的影响。 相似文献
122.
逆向卸荷式气体减压阀的动态特性仿真 总被引:4,自引:4,他引:4
考虑到摩擦力、阻尼力及流体流动作用力等主要非线性因素对减压阀动态特性的影响,建立了逆向卸荷式气体减压阀的动态特性数学模型,并对其启动过程与负载变化下的动态响应特性进行了仿真计算,研究了动态过程的压力、温度、流量以及阀芯位移等参数变化情况,分析了不同的参数对减压阀启动特性的影响,提出了改善减压阀动态响应特性的措施。 相似文献
123.
影响双节套筒式延伸喷管展开时间的主要因素 总被引:2,自引:2,他引:2
分析了重力、惯性力、有效动作力、延伸长度对延伸喷管展开时间的影响。其计算结果对套筒式延伸喷管的设计及展开时间预估有指导作用。 相似文献
124.
航天器中一种典型O形密封圈的有限元分析 总被引:2,自引:1,他引:2
对于有密封要求的航天器而言,O形密封圈在其中起到了至关重要的作用。文章首先对一种典型的法兰-O形密封圈结构进行合理的简化建模,然后利用有限元分析软件ABAQUS计算了特定压缩率下O形圈的力学性能参数,并讨论了摩擦系数、安装方式、法兰间隙、内压、温差等因素对密封性能的影响,对航天器密封接口的设计具有现实的指导意义。 相似文献
125.
126.
Hongwei Liu Zhaokui Wang Yulin Zhang 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
The Earth’s gravity field can be measured with high precision by constructing the purely gravitational orbit of the inner-satellite in Inner-formation Flying System (IFS), which is independently proposed by Chinese scholars and offers a new way to carry out gravity field measurement by satellite without accelerometers. In IFS, for the purpose of quickly evaluating the highest degree of recovered gravity field model and geoid error as well as analyzing the influence of system parameters on gravity field measurement, an analytical formula was established by spectral analysis method. The formula can reflect the analytical relationship between gravity field measurement performance and system parameters such as orbit altitude, the inner-satellite orbit determination error, the inner-satellite residual disturbances, data sampling interval and total measurement time. This analytical formula was then corrected by four factors introduced from numerical simulation of IFS gravity field measurement. By comparing computation results from corrected analytical formula and the actual gravity field measurement performance by CHAMP, the correctness and rationality of this analytical formula were verified. Based on this analytical formula, the influences of system parameters on IFS gravity field measurement were analyzed. It is known that gravity field measurement performance is a monotone decreasing function of orbit altitude, the inner-satellite orbit determination error, the inner-satellite residual disturbances, data sampling interval and the reciprocal of total measurement time. There is a match relationship between the inner-satellite orbit determination error and residual disturbances, in other words, the change rate of gravity field measurement performance with one of them is seriously restricted by their relative size. The analytical formula can be used to quantitatively evaluate gravity field measurement performance fast and design IFS parameters optimally. It is noted that the analytical formula and corresponding conclusions are applied to any gravity satellite which measures gravity field by satellite perturbation orbit. 相似文献
127.
浅析提高投篮命中率的技术因素 总被引:1,自引:0,他引:1
本文分析了影响投篮命中率的各种技术因素,并提出了相应的提高命中率的方法,为篮球教学工作提供有益的参考。 相似文献
128.
产品的设计色彩与人的情感心理 总被引:4,自引:0,他引:4
刘涛 《沈阳航空工业学院学报》2000,17(4):84-86
本文讨论了色彩在工业设计中的应用,并通过色彩构成的色相,明度,纯度等概念的探讨,说明了不同的色彩给人以不同的感觉,产生不同的情绪,并进一步说明了色彩在产品设计上的作用与人的心理情感的关系。 相似文献
129.
Judith Lapierre Stphane Bouchard Thibault Martin Michel Perreault 《Acta Astronautica》2009,64(11-12):1304-1313
A simulation for flight of international crew on space station took place in Moscow from July 1999 to April 2000 (SFINCS) at the State Biomedical Institute of Russia (IBMP) isolation chambers. Objectives of this study were to identify concepts of psychosocial adaptation and of social interactions to develop an explanation of the transcultural group performance. Method: constructivist epistemology with grounded theory research and fourth generation evaluation were used. Data on processes and interactions were gathered during 110 days of confinement as a subject and extended to 240 days as an outside scientist. Results indicate that coping is influenced by usual coping strategies and coping behaviors inside. Several stresses and human factor issues were identified altering well being and performance inside the chambers. Enabling and limiting forces are discussed. A theory on transcultural group performance is proposed. Issues are raised that appear critical to selection, training and group performance. 相似文献
130.
刘国华 《郑州航空工业管理学院学报(管理科学版)》2003,21(1):48-50,66
根据社会发展对档案工作的客观要求以及档案工作自身生存、发展的需要,对影响档案信息深层次加工的因素进行了分析,提出了关于档案信息进行深层次加工的对策。 相似文献