运输机任务自适应机翼的气动特性优化研究

有关评估运输机变弯这机翼的气动性能已进行过理论上的初步研究。该研究致力于这种机翼的潜在应用：在很宽的升力变化范围内减小诱导阻力；在着陆的时间上时候产生比较大的升力。作为参考，对装备有现代增升装置，具有相同平面形状的传统机翼进行了相似研究。为了实现评估，采用约束直接优化方法，该方法由涡串分析方法结合多变量函数最小化算法组成。     

北约最新的敌我识别装置

到90年代初期,北约识别系统(NIS)计划的参与国拟用NIS的应答机和询问机来替换目前使用的IFF(敌我识别)系统.这一替换工作约长达25年.然后将需要有一个10年的过渡期,以便严格控制北约防空系统的敌我识别过程.当NIS替换过程全部完成后,西方的防空能力就会大大提高,并使友机误伤率降低到最小.     

基于模糊自适应卡尔曼滤波的大气数据辅助姿态算法

 针对中低精度航姿参考系统(AHRS)在机体机动时不能利用加速度计修正水平姿态,以及噪声统计特性随实际工作情况变化的问题,提出了一种基于模糊自适应卡尔曼滤波的大气数据辅助姿态解算的方法。首先,考虑大气数据系统和航姿参考系统的优势,利用真空速、攻角和侧滑角等大气数据信息对非重力加速度进行补偿,以辅助水平姿态解算;其次,基于模糊自适应卡尔曼滤波原理,对观测模型的参数进行估计和修正,以实现水平姿态的最优估计;最后,选取某型飞机的试飞数据进行仿真验证。仿真结果表明,该方法可使飞机的水平姿态估计精度达到1.3°,且在偏差较大时有明显的纠偏作用。因此,相对于无机动加速度补偿和常规卡尔曼滤波来说,该方法能够更好地进行姿态估计,具有一定的实用价值。     

Interplanetary transfer of photosynthesis: an experimental demonstration of a selective dispersal filter in planetary island biogeography

We launched a cryptoendolithic habitat, made of a gneissic impactite inoculated with Chroococcidiopsis sp., into Earth orbit. After orbiting the Earth for 16 days, the rock entered the Earth's atmosphere and was recovered in Kazakhstan. The heat of entry ablated and heated the rock to a temperature well above the upper temperature limit for life to below the depth at which light levels are insufficient for photosynthetic organisms ( approximately 5 mm), thus killing all of its photosynthetic inhabitants. This experiment shows that atmospheric transit acts as a strong biogeographical dispersal filter to the interplanetary transfer of photosynthesis. Following atmospheric entry we found that a transparent, glassy fusion crust had formed on the outside of the rock. Re-inoculated Chroococcidiopsis grew preferentially under the fusion crust in the relatively unaltered gneiss beneath. Organisms under the fusion grew approximately twice as fast as the organisms on the control rock. Thus, the biologically destructive effects of atmospheric transit can generate entirely novel and improved endolithic habitats for organisms on the destination planetary body that survive the dispersal filter. The experiment advances our understanding of how island biogeography works on the interplanetary scale.     

The first "space" vegetables have been grown in the "SVET" greenhouse using controlled environmental conditions

The paper describes the "SVET" project--a new generation of space greenhouse with small dimensions. Through the use of a minicomputer, "SVET" is fully capable of automatically operating and controlling environmental systems for higher plant growth. A number of preliminary studies have shown the radish and cabbage to be potentially important crops for CELSS (Closed Environmental Life Support System). The "SVET" space greenhouse was mounted on the "CRYSTAL" technological module docked to the Mir orbital space station on 10 June 1990. Soviet cosmonauts Balandin and Solovyov started the first experiments with the greenhouse on 15 June 1990. Preliminary results of seed cultivation over an initial 54-day period in "SVET" are presented. Morphometrical characteristics of plants brought back to Earth are given. Alteration in plant characteristics, such as growth and developmental changes, or morphological contents were noted. A crop of radish plants was harvested under microgravity conditions. Characteristics of plant environmental control parameters and an estimation of functional properties of control and regulation systems of the "SVET" greenhouse in space flight as received via telemetry data is reported.     

The structure of resting bacterial populations in soil and subsoil permafrost

The structure of individual cells in microbial populations in situ of the Arctic and Antarctic permafrost was studied by scanning and transmission electron microscopy methods and compared with that of cyst-like resting forms generated under special conditions by the non-spore-forming bacteria Arthrobacter and Micrococcus isolated from the permafrost. Electron microscopy examination of microorganisms in situ revealed several types of bacterial cells having no signs of damage, including "dwarf" curved forms similar to nanoforms. Intact bacterial cells in situ and frozen cultures of the permafrost isolates differed from vegetative cells by thickened cell walls, the altered structure of cytoplasm, and the compact nucleoid, and were similar in these features to cyst-like resting forms of non-spore-forming "permafrost" bacterial strains of Arthrobacter and Micrococcus spp. Cyst-like cells, being resistant to adverse external factors, are regarded as being responsible for survival of the non-spore-formers under prolonged exposure to subzero temperatures and can be a target to search for living microorganisms in natural environments both on the Earth and on extraterrestrial bodies.     

Ultraviolet-stimulated fluorescence and phosphorescence of aromatic hydrocarbons in water ice

A principal goal of astrobiology is to detect and inventory the population of organic compounds on extraterrestrial bodies. Targets of specific interest include the wealth of icy worlds that populate our Solar System. One potential technique for in situ detection of organics trapped in water ice matrices involves ultraviolet-stimulated emission from these compounds. Here, we report a preliminary investigation into the feasibility of this concept. Specifically, fluorescence and phosphorescence of pure benzene ice and 1% mixtures of benzene, toluene, p-xylene, m-xylene, and o-xylene in water ice, respectively, were studied at temperatures ranging from ～17 K up to 160 K. Spectra were measured from 200-500 nm (50,000-20,000 cm(-1)) while ice mixtures were excited at 248.6 nm. The temperature dependence of the fluorescence and phosphorescence intensities was found to be independent of the thermal history and phase of the ice matrix in all cases examined. All phosphorescent emissions were found to decrease in intensity with increasing temperature. Similar behavior was observed for fluorescence in pure benzene, while the observed fluorescence intensity in water ices was independent of temperature.     

PHYSIOLAB: a cardiovascular laboratory

PHYSIOLAB is a cardio-vascular laboratory designed by CNES in cooperation with IMBP, with double scientific and medical goals: -a better understanding of the basic mechanisms involved in blood pressure and heart rate regulation, in order to predict and control the phenomenon of cardio-vascular deconditionning. -a real-time monitoring of cosmonauts during functional tests. Launched to the MIR station in 1996, this laboratory was set up and used for the first time by Claudie Andre-Deshays during the French mission "Cassiopeia". The scientific program is performed pre, post and in-flight to study phenomena related to the transition to microgravity as well as the return to the earth conditions. Particular emphasis was placed on the development of the real-time telemetry to monitor LBNP test. This function was successful during the Cassiopeia mission, providing the medical team at TSOUP (MIR Control Center in Moscow) with efficient means to control the physiological state of the cosmonaut. Based on the results of this first mission, IMBP and CNES will go on using Physiolab with Russian crews. CNES will take advantage of the upcoming French missions on MIR to improve the system, and intends to develop a new laboratory for the International Space Station.