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151.
Vestibular disturbances in connection with space flight were reported by a majority of participating astronauts and cosmonauts. These include motion sickness symptoms in the first few days of the space flight, as well as standing, gait and orientation disturbances after the return to Earth. The Aerospace Medical Community has been trying to select those people that are particularly adapted to the above stresses or that can be further adapted through training programs. As the circle of selectees extends to women, the problem arises as to whether differences between men and women exist under the conditions of space flight. In seeking answers to this question we studied a group of 42 women and 44 men, who were further subdivided according to their subjective motion sickness sensitivity, as determined by a questionnaire. Using this material, 26 men and 22 women were designated as motion sickness resistant, and 18 men and 20 women were designated as nonresistant. The vestibular test battery given these test subjects consisted of caloric, rotatory, optokinetic, vestibulo-spinal and vestibulo-vegetative testing. Because of the mixed orthostatic and vestibular problems seen after space flights, we also studied the response of the vestibular apparatus during peripheral blood pooling as induced by lower body negative pressure. The collected historical and test data are analyzed in this paper with emphasis on the relationship to motion sickness tendency. 相似文献
152.
The results of cross-correlation analysis between electrons fluxes (with energies of > 0.6MeV, > 2.0 MeV and > 4.0MeV), geomagnetic indices and solar wind parameters are shown in the paper. It is determined that the electron fluxes are controlled not only by the geomagnetic indices, but also by the solar wind parameters, and the solar wind velocity demonstrates the best relation with the electron fluxes. Numerical value of the relation efficiency of external parameters with the highly energetic electrons fluxes shows a periodicity. It is presented here the preliminary results of daily averaged electrons fluxes forecast for a day ahead on the basis of the model of neuron networks. 相似文献
153.
154.
Adriani A Coradini A Filacchione G Lunine JI Bini A Pasqui C Calamai L Colosimo F Dinelli BM Grassi D Magni G Moriconi ML Orosei R 《Astrobiology》2008,8(3):613-622
The Jovian InfraRed Auroral Mapper (JIRAM) has been accepted by NASA for inclusion in the New Frontiers mission "Juno," which will launch in August 2011. JIRAM will explore the dynamics and the chemistry of Jupiter's auroral regions by high-contrast imaging and spectroscopy. It will also analyze jovian hot spots to determine their vertical structure and infer possible mechanisms for their formation. JIRAM will sound the jovian meteorological layer to map moist convection and determine water abundance and other constituents at depths that correspond to several bars pressure. JIRAM is equipped with a single telescope that accommodates both an infrared camera and a spectrometer to facilitate a large observational flexibility in obtaining simultaneous images in the L and M bands with the spectral radiance over the central zone of the images. Moreover, JIRAM will be able to perform spectral imaging of the planet in the 2.0-5.0 microm interval of wavelengths with a spectral resolution better than 10 nm. Instrument design, modes, and observation strategy will be optimized for operations onboard a spinning satellite in polar orbit around Jupiter. The JIRAM heritage comes from Italian-made, visual-infrared imaging spectrometers dedicated to planetary exploration, such as VIMS-V on Cassini, VIRTIS on Rosetta and Venus Express, and VIR-MS on the Dawn mission. 相似文献
155.
Over the next 2 decades, NASA and ESA are planning a series of space-based observatories to detect and characterize extrasolar planets. This first generation of observatories will not be able to spatially resolve the terrestrial planets detected. Instead, these planets will be characterized by disk-averaged spectroscopy. To assess the detectability of planetary characteristics in disk-averaged spectra, we have developed a spatially and spectrally resolved model of the Earth. This model uses atmospheric and surface properties from existing observations and modeling studies as input, and generates spatially resolved high-resolution synthetic spectra using the Spectral Mapping Atmospheric Radiative Transfer model. Synthetic spectra were generated for a variety of conditions, including cloud coverage, illumination fraction, and viewing angle geometry, over a wavelength range extending from the ultraviolet to the farinfrared. Here we describe the model and validate it against disk-averaged visible to infrared observations of the Earth taken by the Mars Global Surveyor Thermal Emission Spectrometer, the ESA Mars Express Omega instrument, and ground-based observations of earthshine reflected from the unilluminated portion of the Moon. The comparison between the data and model indicates that several atmospheric species can be identified in disk-averaged Earth spectra, and potentially detected depending on the wavelength range and resolving power of the instrument. At visible wavelengths (0.4-0.9 microm) O3, H2O, O2, and oxygen dimer [(O2)2] are clearly apparent. In the mid-infrared (5-20 microm) CO2, O3, and H2O are present. CH4, N2O, CO2, O3, and H2O are visible in the near-infrared (1-5 microm). A comprehensive three-dimensional model of the Earth is needed to produce a good fit with the observations. 相似文献
156.
Detectability of planetary characteristics in disk-averaged spectra II: synthetic spectra and light-curves of earth 总被引:1,自引:0,他引:1
Tinetti G Meadows VS Crisp D Kiang NY Kahn BH Bosc E Fishbein E Velusamy T Turnbull M 《Astrobiology》2006,6(6):881-900
Spatially and spectrally resolved models were used to explore the observational sensitivity to changes in atmospheric and surface properties and the detectability of surface biosignatures in the globally averaged spectra and light-curves of the Earth. Compared with previous efforts to characterize the Earth using disk-averaged models, a more comprehensive and realistic treatment of the surface and atmosphere was taken into account here. Our results are presented as a function of viewing geometry and phases at both visible/near-infrared (0.5-1.7 microm) and mid-infrared (5-25 microm) wavelength ranges, applicable to the proposed NASA-Terrestrial Planet Finder visible coronagraph and mid-infrared interferometer and to the ESADarwin mission architectures. Clouds can change the thermal emission by as much as 50% compared with the cloud-free case and increase the visible albedo by up to 500% for completely overcast cases at the dichotomy phase. Depending on the observed phase and their distribution and type, clouds can also significantly alter the spectral shape. Moreover, clouds impact the detectability of surface biosignatures in the visible wavelength range. Modeling the disk-averaged sensitivity to the "red-edge," a distinctive spectral signature of vegetation, showed that Earth's land vegetation could be seen in disk-averaged spectra, even with cloud cover, when the signal was averaged over the daily time scale. We found that vegetation is more readily discriminated from clouds at dichotomy (50% illumination) rather than at full phase. The detectability of phytoplankton was also explored, but was found to be more difficult to detect in the disk-average than land vegetation. 相似文献
157.
描述了具有最低旁瓣电平和使用粒子群优化算法(PSO)控制零陷的线性阵几何综合方法。PSO是一种最新开发的高性能优化算法,它能解决一般的N维线性和非线性优化问题。与遗传算法和模拟退火等其他进化算法相比,PSO算法更易于理解和实现,并且要求最少的数学预处理。针对以旁瓣抑制(SLL)和/或在特定方向放置零陷为目标的优化问题,首先提出了阵列几何综合的公式,然后运用PSO算法来解决单元的位置优化问题。最后给出了3个PSO算法应用的设计实例,且每个实例中的优化目标都易于实现。通过与使用二次规划方法(QPM)获得的结果相比较,验证了PSO算法结果的有效性。 相似文献
158.
哈勃太空望远镜(HST)的卫星遥测处理工作主要由专用软件和专用硬件完成,HST地面系统的操作和维护费用都很高。为了在2000年前使卫星地面系统的操作和维护费用降下来,NASA已决定改造HST的控制中心系统,从而增强其数据处理能力,降低操作难度,提高系统标准化程度。为此成立了Vision2000控制中心系统(CCS)产品开发工作组,重新设计和开发HST地面系统。CCS地面系统的开发包括:前端处理机( 相似文献
159.
Larmor size transient structures with density depletions as large as 99% of ambient solar wind density levels occur commonly upstream of Earth's collisionless bow shock. These "density holes" have a me... 相似文献
160.
中国航空事业的发展过程是复杂的。开创早期 ,中国从西方几个航空先进国家购买若干名牌产品 ,其中有的型号是仅为中国生产的。寇梯士霍克 (CURTISS HAWK)双翼及单翼战斗机是在 1 930年由美国出口售给中国。到第二次世界大战开始时 ,寇梯士公司曾出口 2 99架双翼机 ,另在两个国家特许制造若干架。寇梯士 75机有两种出口型。一种是带有固定起落架 ,装有莱特赛克隆 780马力发动机 ,简称为 H— 75。此型飞机自 1 937年为中国、泰国、阿根廷共生产 73架。另一种为稍重而轻快飞机 ,有可回收起落架 ,装置双 WASP或CYCL ONE1 1 0 0 / 1 2 … 相似文献