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201.
Automation and Robotics (A&R) systems are a key technology for Mars exploration. All over the world initiatives in this field aim at developing new A&R systems and technologies for planetary surface exploration. From December 2000 to February 2002 Kayser-Threde GmbH, Munich, Germany lead a study called AROMA (Automation and Robotics for Human Mars Exploration) under ESA contract in order to define a reference architecture of A&R elements in support of a human Mars exploration program. One of the goals of this effort is to initiate new developments and to maintain the competitiveness of European industry within this field. 相似文献
202.
Fluid inclusions in minerals hold the potential to provide important data on the chemistry of the ambient fluids during mineral precipitation. Especially interesting to astrobiologists are inclusions in low-temperature minerals that may have been precipitated in the presence of microorganisms. We demonstrate that it is possible to obtain data from inclusions in chemosynthetic carbonates that precipitated by the oxidation of organic carbon around methane-bearing seepages. Chemosynthetic carbonates have been identified as a target rock for astrobiological exploration. Other surficial rock types identified as targets for astrobiological exploration include hydrothermal deposits, speleothems, stromatolites, tufas, and evaporites, each of which can contain fluid inclusions. Fracture systems below impact craters would also contain precipitates of minerals with fluid inclusions. As fluid inclusions are sealed microchambers, they preserve fluids in regions where water is now absent, such as regions of the martian surface. Although most inclusions are < 5 microns, the possibility to obtain data from the fluids, including biosignatures and physical remains of life, underscores the advantages of technological advances in the study of fluid inclusions. The crushing of bulk samples could release inclusion waters for analysis, which could be undertaken in situ on Mars. 相似文献
203.
The purpose of this study is to examine human adaptation of a three members' crew during a 135 days MIR flight simulation and to compare and validate psychological methods for monitoring and support in flight. The main findings showed that isolation was not a key factor for the subjects who were more concerned by recreational activities, family, and work. The individual reactions to stress of the crew members were to project their problems on the others. These reactions had some consequences upon the group: Although the three subjects developed a weak tendency to "group think", one of the crew members was considered as less integrated to the group by the other two subjects, who, however, acted to protect (successfully) the general cohesion and mood of the crew. From a methodological point of view, baseline data predicted the difficulties that occurred for one of the crew member. Both quantitative and qualitative tools were adequate, although qualitative tests gave a closer approach to the actual situation that developed during the simulation. 相似文献
204.
Iwasaki K Hirayanagi KI Sasaki T Kinoue T Ito M Miyamoto A Igarashi M Yajima K 《Acta Astronautica》1998,42(1-8):175-183
Usefulness of a short-arm human centrifuge is expected when it is used in space as a countermeasure against cardiovascular deconditioning, problem of bone-calcium metabolism, etc. However, nothing is solidly established regarding the most desirable program for artificial G application. Accordingly, this study was designed to analytically evaluate the effects of repeated long duration +Gz load on human cardiovascular function. Recently heart rate spectral analysis has been recognized as a powerful tool for quantitatively evaluating parasympathetic and sympathetic activity separately in human. It is reported that power of the high frequency component (HF-p) is mediated selectively by parasympathetic activity and the power ratio of low to high frequency components(LF/HF) is indicative of cardiac sympathetic activity or cardiac sympathovagal balance. Sequence method is developed to examine spontaneous baroreceptor reflex sensitivity (BRS). We studied cardiovascular control function by using these methods in 9 healthy men before and after 7 days of daily repeated 1hour +2Gz load. When compared with the data of pre-G load period, post-G load period, decrease of HR, increases of HF-p and BRS were statistically significant. SBP, DBP and LF/HF tended to decrease, however, these changes were not statistically significant. This results indicate that repeated +2Gz load increases parasympathetic activity and arterial baroreceptor-cardiac reflex sensitivity. In recent years, many investigators suggest that space flight and head-down bedrest leads to impaired baroreceptor-cardiac reflex responses and decrease of parasympathetic activity, which may contribute to orthostatic intolerance. So our results suggest that daily repeated 1hour +2Gz load would be useful in preventing post-flight orthostatic intolerance. 相似文献
205.
二阶多项式自治系统代数曲线解的判定法 总被引:5,自引:0,他引:5
为了以解析的方法和代数的方法寻求二阶多项式自治系统的代数曲线解,并为进一步研究非线性系统的可积性和得域上多项系统的定理论,证明了关于复域上二元多项式的一个整除定理,并以VanDerPol程及一个二阶二次自治系统为例,说明这一整除定量可以作为二阶多项自治系统是否存在代数曲线解的主要判据。 相似文献
206.
何小瓦%李恩%张其劭%郭高凤 《宇航材料工艺》2005,35(1):20-23
介绍了在微波及毫米波段介质材料复介电常数在-253—1400℃的变温测试方法,即网络参数法和谐振腔法,并对这些方法进行了优缺点分析,总结出变温测试方法的概况、趋势及技术特点。 相似文献
207.
Astronauts are often required to work in shift schedules. To test pre-mission adaptation strategies and effects on the circadian system, a study was performed using microgravity simulation by head-down bedrest. Eight male subjects were studied over 4 control days, and 7 days each for pre-mission adaptation, bedrest, and readjustment. The circadian system was assessed by monitoring ECG and temperature, and by collecting urine for determination of hormones and electrolytes. Rhythms did not achieve complete adjustment within the adaptation period when the sleep-wake cycle was shortened by 1 h/day, but resynchronization continued during bedrest. After the bedrest period when the time shift was reversed by a 7-h delay within 2 days, resynchronization was achieved satisfactorily only within 7 days. From the results it is concluded that a sleep-wake cycle advance as used in this study is insufficient to keep the circadian system in pace. Under operational conditions the circadian system of astronauts may become longer and more destabilized than under controlled laboratory conditions. 相似文献
208.
本文介绍针对固定温度点的热力学函数 (如焓、熵、比热 )综合近似计算法。该方法已成功地用来近似计算温度范围为 10 0~ 2 0 0 0 0 K的 150 0个热力学函数表。用内含近似计算程序包的 TD软件系统对混合物参数进行热力计算的结果证明,该多项式在求解多组元系统计算中迭代问题时具有很高的可靠性。 相似文献
209.
已经发展了一种工作温度高达1950°F的新型的圆箔热流计。它的最重要的特点是在高温时,保持了高的灵敏度,而一般传统的康铜箔·铜热流计,在高温时灵敏度将下降30%以上。此外,由于使用了低导热率的圆箔,较高的热电功率输出,改进了时间常数,使其灵敏度获得了成倍的增长。热流计组件的全焊接结构,使它能适应在任何一种金属材料中工作。这些特点,除了高温灵敏度以外,也可以从其他一些标准热电偶如镍铬箔·康铜中获得。文中列出了标准热电偶材料的一些性能数据,并与新型的圆箔热流计在不同温度时的灵敏度作了对比。 相似文献
210.
去年11月,美空军正式透露了两种可逃避雷达监测的秘密的隐身飞机。一种隐身飞机是由诺思罗普公司和波音公司联合研制的B-2先进技术轰炸机,在加州棕榈谷工厂首次公开展出并进行了初期试验。另一种隐身飞机命名为F-117A战斗机,现已被空军所证实,展示了飞机照片,并进行了简要的新闻发布会。这种似蝙蝠的短而粗的喷气式飞机是由洛克希德公司制造的,自1983年起已陆续交付使用,目前在内华达州的内利斯空军基地共部署了52架。五角大楼之所以公开F-117A飞机的秘密;主要是因为该机要进行更广泛的日间飞行。 相似文献