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51.
K.Ya. Kondratyev V.V. Kozoderov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1985,5(6):105-109
Based on the 1974–78 NOAA data, characteristic features of the variability of the Earth's radiation budget and its components over the area of the Northern Atlantic have been analyzed. Calculations of the mean square deviation for the ERB and its components have let to the conclusions that anomalous regions of maximum variability may be considered as energy-active zones. 相似文献
52.
Pricing policy for Earth observation data continues to be a problem for both supplier organizations and user organizations: there are incompatible or conflicting pricing policies used by different organizations in the Earth observation sector. This paper analyses the issues in Earth observation data pricing in two ways. First, it analyses the policy foundations which underlie Earth observation data pricing, such as return on investment, the basis of pricing policy and access conditions. Second, it presents five policy options for the pricing of Earth observation data, namely free data, marginal cost price, market driven price, two tier pricing and rebalancing of government funding. The paper concludes with an analysis of the forces acting on Earth observation data pricing policy. 相似文献
53.
54.
D.N. Mukhin A.M. Feigin Ya.I. Molkov E.V. Suvorov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2006,37(12):2292-II
A technique for retrieving vertical distributions (profiles) of atmospheric gas constituents from data of passive remote sensing of the atmosphere is proposed. The goal of the technique based on the statistical (Bayesian) approach to solution of inverse problems is construction of probability distribution for a sought quantity throughout the interval of the studied heights. It is assumed that initial data contain measurement noise, and a priori information about properties of the profile is used. It is proposed to approximate the sought profile by a function in the form of an artificial neural network. This approximation allows optimal inclusion of a priori information into retrieval procedure, thus ensuring the most effective regularization of the problem. Efficiency of the proposed technique is demonstrated on an example of retrieval of vertical ozone profile from data of ground-based sounding of the atmosphere in the millimeter wavelength range. Results of profile retrieval from model data and from spectra of radiation temperature of the atmosphere measured in the Apatity (67° N, 33° E) in the winter of 2002–2003 are presented. 相似文献
55.
I.Ya. Plotnikov E.S. Barkova 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2007,40(12):1858-1862
Using the Dst and AE geomagnetic index values and parameters of interplanetary magnetic field and solar wind we have examined the geoeffectiveness of transient ejections in the solar wind, namely, magnetic clouds and high-speed streams. It is found that for magnetic clouds the dependences of indices on the solar wind electric field are nonlinear of different kind. In contrast to magnetic clouds, the dependence of Dst and AE geomagnetic index values on the solar wind electric field agrees closely with the linear one for high-speed streams. We suggest approximating formulas to describe dependences obtained taking into account the relation of the electric field transpolar potential to the electric field and dynamic pressure of the solar wind. We suppose that the interplanetary magnetic field fluctuations also contribute to these dependences. 相似文献
56.
57.
Yu. Ya. Fershalov 《Russian Aeronautics (Iz VUZ)》2012,55(4):424-429
In this paper, a technique for the refined determination of turbine stage model parameters to investigate gasodynamic processes in the turbine flow passages without regard to uncontrolled heat exchange with environment is suggested. 相似文献
58.
Space Science Reviews - 相似文献
59.
Using the results of numerical modeling of nonstationary gas hydrodynamic working processes in the gas conduit variable section
channel when removing and cooling hot gases of different purpose technical plants, an engineering technique has been developed
to provide the gas conduit operation under limitations on the flow temperature in the outlet plant section. A multiparametric
area of permissible gas conduit operation connecting the characteristics of technical plants, gas conduit and water feeding
system is presented. 相似文献
60.
O. T. Demkiv E. L. Kordyum O. R. Kardash O. Ya. Khorkavtsiv 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1999,23(12):1999-2004
The gravitropism of protonemata of Pohlia nutans is described and compared with that of other mosses. In darkness, protonemata showed negative gravitropism. Under uniform illumination they grew radially over the substrate surface, whereas unilateral illumination induced positive phototropic growth. Gravitropism was coupled with starch synthesis and amyloplast formation. Protonematal gravitropic growth is more variable than the strict negative gravitropism of Ceratodon chloronema. 相似文献