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511.
C.M. Wrasse J. Fechine H. Takahashi C.M. Denardini J. Wickert M.G. Mlynczak J.M. Russell C.L. Barbosa 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(9):1423-1428
Global Positioning System (GPS) receiver on the CHAllenging Mini-satellite Payload (CHAMP) and the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument, one of four on board the TIMED satellite, provide middle atmosphere temperature profiles by Radio Occultation (RO) and limb viewing infrared emission measurements, respectively. These temperature profiles retrieved by two different techniques in the stratosphere are compared with each other using more than 1300 correlative profiles in March, September and December 2005. The over-all mean differences averaged over 15 and 35 km are approximately −2 K and standard deviation is less than 3 K. Below 20 km of altitude, relatively small mean temperature differences ∼1 K are observed in wide latitudinal range except for June (during the SABER nighttime observation). In the middle to low latitudes, between 30°S and 30°N, the temperature difference increases with height from ∼0–1 K at 15 km, to ∼−4 K at 35 km of altitude. Large temperature differences about −4 to −6 K are observed between 60°S and 30°N and 31–35 km of altitude for all months and between 0° and 30°N below 16 km during June (nighttime). 相似文献
512.
513.
It is shown that an operational amplifier with four commutated capacitors in the feedback path produces an output signal whose fundamental is equal in magnitude but 180 degrees out of phase with the input. The analysis is carried out by expressing the output signal in a Fourier series. 相似文献
514.
Harlan L. McKim Carolyn J. Merry 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1985,5(5):61-71
During the summer of 1983 three Corps of Engineers project sites were overflown as part of the SPOT (Système Probatoire d'Observation de la Terre) High Resolution Visible (HRV) simulation campaign. The three sites were Chesapeake Bay, Maryland, Berlin Lake, Ohio, and Lac qui Parle, Minnesota. Multispectral imagery data at a 20-m resolution for three spectral bands (0.50–0.59 μm, 0.61–0.68 μm, 0.79–0.89 μm) were obtained for each of the sites. The data were analyzed for use in dredging, recreation resource management, water quality, and wildlife habitat applications. 相似文献
515.
Estimates of drag characteristics of the space vehicles with orbit heights of 450–540 and 700–900 km before and after strong
(with a magnitude M ≥ 6.5) crust earthquakes of 2000–2006 are presented. The method of estimation of seismic orbital effects is presented using
as an example the small Mozhaets-4 spacecraft. Two weeks prior to earthquakes, variations in the drag of low-orbital spacecraft increase. 3–6 days prior to
strong crust earthquakes with epicenters on the land, the drag of low-orbit spacecraft in the upper atmosphere increases.
The effect of increased viscosity of the neutral component of the atmosphere at spacecraft heights 3–6 days prior to strong
crust earthquakes is consistent with the results of studies of disturbances in the ionization density variations in the ionospheric
F region prior to earthquakes. No anomalies are found in the day of the earthquake. In the future, it is proposed to use elements
of space debris for diagnostics of seismic orbital effects and disturbances of the upper atmosphere. 相似文献
516.
S. Guo X. LiuW. Ai Y. TangJ. Zhu X. WangM. Wei L. QinY. Yang 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(5):736-741
Based on a formerly developed ground-based prototype of space plant-growing facility, the development of its improved prototype has been finished, so as to make its operating principle better adapt to the space microgravity environment. According to the developing experience of its first generation prototype and detailed demonstration and design of technique plan, its blueprint design and machining of related components, whole facility installment, debugging and trial operations were all done gradually. Its growing chamber contains a volume of about 0.5 m3 and a growing area of approximate 0.5 m2; the atmospheric environmental parameters in the growing chamber and water content in the growing media were controlled totally and effectively; lighting source is a combination of both red and blue light emitting diodes (LED). The following demonstrating results showed that the entire system design of the prototype is reasonable and its operating principle can nearly meet the requirements of space microgravity environment. Therefore, our plant-growing technique in space was advanced further, which laid an important foundation for next development of the space plant-growing facility and plant-cultivating experimental research in space microgravity condition. 相似文献
517.
Stephen W. Bougher Pierre-Louis Blelly Michael Combi Jane L. Fox Ingo Mueller-Wodarg Aaron Ridley Raymond G. Roble 《Space Science Reviews》2008,139(1-4):107-141
Numerical modeling tools can be used for a number of reasons yielding many benefits in their application to planetary upper atmosphere and ionosphere environments. These tools are commonly used to predict upper atmosphere and ionosphere characteristics and to interpret measurements once they are obtained. Additional applications of these tools include conducting diagnostic balance studies, converting raw measurements into useful physical parameters, and comparing features and processes of different planetary atmospheres. This chapter focuses upon various classes of upper atmosphere and ionosphere numerical modeling tools, the equations solved and key assumptions made, specified inputs and tunable parameters, their common applications, and finally their notable strengths and weaknesses. Examples of these model classes and their specific applications to individual planetary environments will be described. 相似文献
518.
Algorithms for determining fixed-pitch propeller parameters and some flight characteristics of a superlight aircraft at the early stage of designing are described. 相似文献
519.
520.
G.D. Aburjania L.S. Alperovich A.G. Khantadze O.A. Kharshiladze 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(4):624-627
The paper presents a physical mechanism of large-scale vortex electric field generation in the ionospheric E- and F-layers. It shows that the planetary-scale, synoptic short-period (from several second to several hours) and fast processes (with propagation velocity higher than 1 km/s) produce a planetary-scale internal vortex electric field. Its value may far exceed that of the dynamo-field generated in the same ionospheric layer by local wind motion. We found, that an ionospheric source of the vortex electric field is spatial inhomogeneity of the geomagnetic field. 相似文献