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731.
飞行体的海空背景反射与辐射计算 总被引:2,自引:0,他引:2
徐南荣 《北京航空航天大学学报》1998,24(2):237-240
研究了对近海飞行体的红外特性有重要影响的海空背景辐射的反射特性.讨论了波浪面起伏随机规律,随机起伏对海面自身辐射及对阳光反射的影响,推演了此种随机起伏波浪面的自身辐射及反射的阳光在观测点形成的辐照度的计算方法.给出的算例结果表明,海空背景对飞行体的红外特性尤其对其前半球的红外特性有重要的意义. 相似文献
732.
用不同年代的国际地磁参考场(IGR)模式及最新的辐射带粒子通量模式,计算了低高度上空间某点的辐射带质子通量随时间的变化,讨论了地磁场的长期变化对L-B坐标及辐射带带电粒子通量计算的影响,对正确使用地磁场模式计算磁壳参量L及辐射带粒子通量模式给予了说明和建议. 相似文献
733.
电子束固化技术及在复合材料制造领域的应用 总被引:4,自引:0,他引:4
对辐射固化与光固化进行了比较,阐述了电子束辐射固化的基本过程,并对电子束固化复合材料的技术特点进行了概述.此外,还详细总结了电子束固化复合材料技术的发展状况,包括可电子束固化的树脂体系,辐敏剂以及活性稀释剂的选择和应用,固化机理的研究等.最后,还对复合材料的低能电子束固化技术以及新型树脂体系的探索进行了总结. 相似文献
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M. Puchalska L. Sihver T. Sato T. Berger G. Reitz 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2012
The radiation environment at the altitude of the International Space Station (ISS) is substantially different than anything typically encountered on Earth in both the character of the radiation field and the significantly higher dose rates. Concerns about the biological effects on humans of this highly complex natural radiation field are increasing due to higher amount of astronauts performing long-duration missions onboard the ISS and especially if looking into planned future manned missions to Mars. In order to begin the process of predicting the dose levels seen by the organs of an astronaut, being the prerequisite for radiation risk calculations, it is necessary to understand the character of the radiation environment both in- and outside of the ISS as well as the relevant contributions from the radiation field to the organ doses. 相似文献
739.
T.P. Dachev 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
Space weather and related ionizing radiation has been recognized as one of the main health concerns for the International Space Station (ISS) crew. The estimation of the radiation effect on humans outside the ISS requires at first order accurate knowledge of their accumulated absorbed dose rates, which depend on the global space radiation distribution, solar cycle and local variations generated by the 3D mass distribution surrounding the ISS. The R3DE (Radiation Risks Radiometer-Dosimeter for the EXPOSE-E platform) on the European Technological Exposure Facility (EuTEF) worked successfully outside of the European Columbus module between February 2008 and September 2009. A very similar instrument named R3DR for the EXPOSE-R platform worked outside the Russian Zvezda module of the ISS between March 2009 and August 2010. Both are Liulin-type detectors, Bulgarian-built miniature spectrometer-dosimeters. The acquired approximately 5 million deposited energy spectra from which the flux and absorbed dose rate were calculated with 10 s resolution behind less than 0.41 g cm−2 shielding. This paper analyses the spectra collected in 2009 by the R3DE/R instruments and the long-term variations in the different radiation environments of Galactic Cosmic Rays (GCR), inner radiation belt trapped protons in the region of the South Atlantic Anomaly (SAA) and relativistic electrons from the Outer Radiation Belt (ORB). The R3DE instrument, heavily shielded by the surrounding structures, measured smaller primary fluxes and dose rates from energetic protons from the SAA and relativistic electrons from the ORB but higher values from GCRs because of the contribution from secondary particles. The main conclusion from this investigation is that the dose rates from different radiation sources around the International Space Station (ISS) have a large special and temporal dynamic range. The collected data can be interpreted as possible doses obtained by the cosmonauts and astronauts during Extra Vehicular Activities (EVA) because the R3DE/R instruments shielding is very similar to the Russian and American space suits average shielding (, and ). Fast, active measurements are required to assess accurately the dose accumulated by astronauts during EVA. 相似文献
740.
为提高导航卫星精密定轨与轨道预报精度,提出了一种导航卫星太阳光压摄动的分析建模方法.相较于其他摄动因素模型完善且精度较高,光压摄动由于太阳活动导致太阳能量误差、卫星姿态控制误差和表面材料老化等问题,是最难以精确建模的摄动源,也是动力学模型最大的误差源.基于此,提出了一种基于卫星的姿态控制规律,通过分析法建立卫星太阳光压摄动模型,给出了光压摄动加速度在星体坐标系中的模型,并以GPSBlock IIR为例进行了验证.计算结果表明,该仿真分析法所建立的摄动模型与T30模型、ECOM模型精度接近,达到了光压建模研究的初步计算要求. 相似文献