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371.
N. M. Bodunov 《Russian Aeronautics (Iz VUZ)》2011,54(1):89-94
A mathematical model of the process of bending and rolling the thin-walled components is presented taking into account the
geometrical nonlinearity. Also presented is the technique for calculating the setup variables of bending equipment, which
is based on reduction of the initial differential boundary-value problem to the discrete one with the use of the finite difference
method. 相似文献
372.
373.
I. Martínez J.M. Perales 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
The experimental results obtained in experiment “STACO” made on board the Spacelab D-2 are re-visited, with image-analysis tools not then available. The configuration consisted of a liquid bridge between two solid supporting discs. An expected breakage occurred during the experiment. The recorded images are analysed and the measured behaviour compared with the results of a three dimensional model of the liquid dynamics, obtaining a much better fit than with linear models. 相似文献
374.
The paper presents a technique of forming and evaluating the allowable clearance between a launch vehicle fairing and spacecraft. 相似文献
375.
The results of the interplanetary scintillation observations performed in the period of the maximum of solar activity from April 2013 to April 2014 on the BSA LPI radio telescope at the frequency 111MHz are presented. Fluctuations of the radio emission flux were recorded round the clock for all sources with a scintillating flux of more than 0.2 Jy falling in a strip of sky with a width of 50° over declinations corresponding to a 96-beam directional pattern of the radio telescope. The total number of sources observed during the day reaches 5000. The processing of the observational data was carried out on the assumption that a set of scintillating sources represents a homogeneous statistical ensemble. Daily two-dimensional maps of the distribution of the level of scintillations, whose analysis shows the strong nonstationarity and large-scale irregularity of the spatial distribution of solar wind parameters, were constructed. According to maps of the distribution of the level of scintillations averaged over monthly intervals, the global structure of the distribution of the solar wind was investigated in the period of the maximum of solar activity, which was found to be on the average close to spherically symmetric. The data show that on a spherically symmetric background an east–west asymmetry is observed, which indicates the presence of a large-scale structure of a spiral type in the solar wind. 相似文献
376.
M.R. Saradjian M. Hosseini 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
In the past studies, different soil moisture estimation models were developed for bare soil areas by using remotely-sensed data. However, there are few models that can be used to estimate soil moisture in vegetated areas. Water Cloud Model (WCM) model is a widely used soil moisture estimation model has been developed for vegetated areas. In this study, the WCM model was extended to take soil roughness parameter into consideration. The modeling and its accuracy assessment were done by using multi-polarization Airborne Synthetic Aperture Radar (AIRSAR) images and ground data collected during field Soil Moisture Experiments. 相似文献
377.
378.
This paper deals with the technical features of designing an information-controlling system to prevent critical operating conditions of the helicopter flight, a technique for evaluating its effectiveness, analysis and synthesis of the measurement channels, forming of warning signals, and information support of the crew in abnormal situations. 相似文献
379.
C. J. Hansen M. A. Caplinger A. Ingersoll M. A. Ravine E. Jensen S. Bolton G. Orton 《Space Science Reviews》2017,213(1-4):475-506
Junocam is a wide-angle camera designed to capture the unique polar perspective of Jupiter offered by Juno’s polar orbit. Junocam’s four-color images include the best spatial resolution ever acquired of Jupiter’s cloudtops. Junocam will look for convective clouds and lightning in thunderstorms and derive the heights of the clouds. Junocam will support Juno’s radiometer experiment by identifying any unusual atmospheric conditions such as hotspots. Junocam is on the spacecraft explicitly to reach out to the public and share the excitement of space exploration. The public is an essential part of our virtual team: amateur astronomers will supply ground-based images for use in planning, the public will weigh in on which images to acquire, and the amateur image processing community will help process the data. 相似文献
380.
V.D. Kuznetsov I.I. Sobelman I.A. Zhitnik S.V. Kuzin Yu.D. Kotov Yu.E. Charikov S.N. Kuznetsov E.P. Mazets A.A. Nusinov A.M. Pankov J. Sylwester 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
The CORONAS-F mission experiments and results have been reviewed. The observations with the DIFOS multi-channel photometer in a broad spectral range from 350 to 1500 nm have revealed the dependence of the relative amplitudes of p-modes of the global solar oscillations on the wavelength that agrees perfectly well with the earlier data obtained in a narrower spectral ranges. The SPIRIT EUV observations have enabled the study of various manifestations of solar activity and high-temperature events on the Sun. The data from the X-ray spectrometer RESIK, gamma spectrometer HELICON, flare spectrometer IRIS, amplitude–temporal spectrometer AVS-F, and X-ray spectrometer RPS-1 have been used to analyze the X- and gamma-ray emission from solar flares and for diagnostics of the flaring plasma. The absolute and relative content of various elements (such as potassium, argon, and sulfur) of solar plasma in flares has been determined for the first time with the X-ray spectrometer RESIK. The Solar Cosmic Ray Complex monitored the solar flare effects in the Earth’s environment. The UV emission variations recorded during solar flares in the vicinity of the 120-nm wavelength have been analyzed and the amplitude of relative variations has been determined. 相似文献