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411.
From 1 January 1986 through 1 January 2008, GOES satellites recorded 170 solar proton events. For 169 of these events, we estimated effective and equivalent dose rates and doses of galactic cosmic radiation (GCR) and solar cosmic radiation (SCR), received by aircraft occupants on simulated high-latitude flights. Dose rate and dose estimates that follow are for altitudes 30, 40, 50, and 60 kft, in that order.  相似文献   
412.
ChangE-1 (CE-1) will be the first satellite of China in lunar orbit. Its Microwave Detector makes real-time and periodical calibration at high and low temperature points. The low brightness temperature calibration source will be provided by calibration antenna which is pointing towards the cold space.  相似文献   
413.
主要通过灯丝放电磁场约束型原子氧剥蚀效应地面模拟设备模拟空间环境,对空间常用材料Kapton进行了原子氧剥蚀效应、温度升高对材料原子氧效应的影响试验以及原子氧与紫外辐射复合效应试验,对试验前后试样的外观、质量及表面形貌进行了比较,得出了材料在设备中的反应特点以及温度变化、紫外辐射对材料的原子氧效应的影响规律.同时测量了原子氧暴露试验前后、原子氧与紫外辐射复合作用前后试样的反射率和透射率,并进行了比较.   相似文献   
414.
飞机发动机冷气道与隔热层的耦合传热分析   总被引:2,自引:1,他引:1  
任德鹏  夏新林  艾青 《航空学报》2005,26(4):426-429
数值研究了某飞机发动机外侧冷气道与隔热层的耦合传热过程。采用低雷诺数k-ε模型与SIMPLEC算法计算通道内可压缩变物性气流的湍流对流换热,采用蒙特卡罗法求解通道壁面间的辐射换热。通道内气流湍流对流换热、壁面间辐射换热与隔热层内导热耦合求解。通过模拟计算,分析了通道与隔热层的耦合传热机制,考察了相关参数的影响。结果表明,在所考虑的通道结构与空气流条件下,冷气道外环壁面的温度高于气流温度,气流对内外环壁面均起冷却作用;在隔热层参数不变条件下,壁面间的辐射换热与气流的对流冷却是该传热过程的控制机制,增大冷气流量、降低壁面发射率均可显著降低隔热层的外壁面温度。  相似文献   
415.
FY—1C卫星空间粒子成分监测器及其探测结果   总被引:1,自引:0,他引:1  
简要介绍了FY-1C星空间粒子成分监测器的任务目标、工作原理、创新特色及在轨探测结果。空间粒子成分监测器用于卫星轨道空间的带电粒子辐射监测,为卫星的在轨安全和抗辐射加固设计服务。监测器在世界上实现用1套传感器完成对高能电子、质子、α粒子至铁离子的全成分监测,使我国首次获得了870km高太阳同步轨道全空间的各种重离子分布、质子能谱分布和电子通量分布,捕捉到大量的地磁暴和太阳质子事件,获得了批重要的探测成果。  相似文献   
416.
根据一般成像系统CCD像元响应非均匀性校正的原理与算法,通过对星载可见光干涉成像光谱仪CCD像元响应非均匀性校正的相对辐射定标原理及所获定标数据的深入分析,研究出了一种适于对可见光及红外干涉成像光谱仪系统CCD像元响应非均匀性进行校正的方法,有效解决了干涉成像光谱仪系统探测器阵列非均匀性校正这一工程技术难题,它对今后该方面的科研和技术工作具有积极的指导意义。  相似文献   
417.
带电粒子辐照将引起材料折射率和消光系数的变化。文章首先介绍了带电粒子在热控涂层中的剂量深度分布,接着利用渐变折射率概念建立了剂量深度分布和材料折射率与消光系数的关系,给出了热控涂层光学性能变化的分析模型,最后对这一理论的应用进行了讨论。  相似文献   
418.
A comprehensive model is developed to study the atomic oxygen OI 8446 Å dayglow emission. The emission rate profiles and intensities are obtained using the recently developed Solar2000 EUV (Extreme Ultra Violet) flux model. These emission profiles are used to construct the morphology of the 8446 Å emission between equator and 45°N in the northern hemisphere. The longitudinal variation of 8446 Å dayglow emission is found about 5% and is not included in the presentation of morphology. A span of five years is chosen to study the effect of varying solar activity on the morphology of the OI 8446 Å dayglow emission. The morphology is studied on April 3 which lies under the equinox conditions. In year 2001 the solar F10.7 index on the chosen date was as high as 223.1 which is the case of solar maximum. From the present calculations it is found that the intensity does not vary linearly with the F10.7 solar index. The morphology shows that the region of maximum emission rate expands towards the higher latitudes as F10.7 solar index increases. The similar effects have also been found in the morphology of 7320 Å dayglow emission (Sunil Krishna and Singh, 2009). The similarities in the morphology of 7320 Å and 8446 Å dayglow emissions further suggest that the photoelectron flux has strong bearing on the production of these emissions.  相似文献   
419.
Literature on solar sailing has thus far mostly considered solar radiation pressure (SRP) as the only contribution to sail force. However, considering a sail in a planetary mission scenario, a new contribution can be added. Since the planet itself emits radiation, this generates a radial planetary radiation pressure (PRP) that is also exerted on the sail. Hence, this work studies the combined effects of both SRP and PRP on a sail for two case studies, i.e. Earth and Venus. In proximity of the Earth, the effect of PRP can be significant under specific conditions. Around Venus, instead, PRP is by far the dominating contribution. These combined effects have been studied for single- and double-sided reflective coating and including eclipse. Results show potential increase in the net acceleration and a change in the optimal attitude to maximise the acceleration in a given direction. Moreover, an increasing semi-major axis manoeuvre is shown with and without PRP, to quantify the difference on a real-case scenario.  相似文献   
420.
The Sun undergoes several well known periodicities in activity, such as the Schwabe 11 year cycle, the Gleissberg 80–90 year cycle, the Suess 200–210 year cycle and the Halstatt 2200–2300 year cycle. In addition, there is evidence that the 20th century levels of solar activity are unusually high. The years 2020–2040 are expected to coincide with increased activity in human space flight beyond low Earth orbit. The solar cycles and the present level of solar activity are reviewed and their activities during the years 2020–2040 are discussed with a perspective on space radiation and the future program of space flight. It is prudent to prepare for continuing levels of high solar activity as well as for the low levels of the current deep minimum, which has corresponded to high galactic cosmic ray flux.  相似文献   
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