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991.
空间目标红外辐射特性分析 总被引:1,自引:0,他引:1
研究空间目标的红外辐射特性,对于探测识别空间目标、监视空间碎片、保障卫星运行安全等问题有重要意义.本文以空间卫星为目标,分析了其红外辐射特性形成的原理,依据空间目标的热平衡方程,应用节点网络法求解目标表面的温度分布,并结合普朗克定律推导空间目标红外辐射度的计算方法,在分析总结相关资料的基础上得到了求解空间目标红外辐射特... 相似文献
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介绍了射频识别读写器的组成和工作原理,"基于RFID的民用飞行维修系统"是一个集"智能数据库技术、射频识别技术、安全技术与网络技术、有线及无线网络技术"等高新技术与实用技术为一体的监测与管理信息系统.该系统把飞行安全检测、飞机部件全程追踪、基于网络的信息平台集成与管理等有机结合.技术领域交叉、研究成果实用.将RFID技... 相似文献
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文章利用预腐蚀后的LY12CZ试件,进行了随机谱和等幅谱加载的疲劳及腐蚀疲劳试验,分析了预腐蚀年限和载荷谱对腐蚀疲劳影响系数的影响。试验结果表明:①腐蚀疲劳影响系数与预腐蚀年限呈递增趋势且当预腐蚀到一定程度时腐蚀疲劳影响系数趋近于1,这意味着在飞机日历寿命的中后期可以不考虑腐蚀疲劳的作用;②腐蚀疲劳影响系数与载荷谱呈现... 相似文献
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将声发射动态无损检测技术引入试件疲劳试验中,通过对试验过程中声发射信号的分析,获取试件的初始裂纹数据.证明声发射技术可以发现试验中试件的初始裂纹,并对其破坏具有预警作用. 相似文献
995.
Mark Nelson B.C. Wolverton 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
The limitations that will govern bioregenerative life support applications in space, especially volume and weight, make multi-purpose systems advantageous. This paper outlines two systems which utilize plants and associated microbial communities of root or growth medium to both produce food crops and clean air and water. Underlying these approaches are the large numbers and metabolic diversity of microbes associated with roots and found in either soil or other suitable growth media. Biogeochemical cycles have microbial links and the ability of microbes to metabolize virtually all trace gases, whether of technogenic or biogenic origin, has long been established. Wetland plants and the rootzone microbes of wetland soils/media also been extensively researched for their ability to purify wastewaters of a great number of potential water pollutants, from nutrients like N and P, to heavy metals and a range of complex industrial pollutants. There is a growing body of research on the ability of higher plants to purify air and water. Associated benefits of these approaches is that by utilizing natural ecological processes, the cleansing of air and water can be done with little or no energy inputs. Soil and rootzone microorganisms respond to changing pollutant types by an increase of the types of organisms with the capacity to use these compounds. Thus living systems have an adaptive capacity as long as the starting populations are sufficiently diverse. Tightly sealed environments, from office buildings to spacecraft, can have hundreds or even thousands of potential air pollutants, depending on the materials and equipment enclosed. Human waste products carry a plethora of microbes which are readily used in the process of converting its organic load to forms that can be utilized by green plants. Having endogenous means of responding to changing air and water quality conditions represents safety factors as these systems operate without the need for human intervention. We review this research and the ability of systems using these mechanisms to also produce food or other useful crops. Concerns about possible pathogens in soils and wastewater are discussed along with some methods to prevent contact, disease transmission and to pre-screen and decrease risks. The psychological benefits of having systems utilizing green plants are becoming more widely recognized. Some recent applications extending the benefits of plants and microbes to solve new environmental problems are presented. For space applications, we discuss the use of in situ space resources and ways of making these systems compact and light-weight. 相似文献
996.
基于卫星热试验与热分析状态差异性分析,根据某遥感卫星热分析和热平衡试验结果,用综合虚拟热试验和有限元的有限差分集成法对其热模型修正技术进行了研究。卫星在轨温度遥测结果表明热模型修正有效。 相似文献
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