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31.
Mars-96 mission: Mars exploration with the use of penetrators   总被引:1,自引:0,他引:1  
Within the frames of the Mars-96 Mission the penetrators were first developed for the investigation of the chemical composition and physical properties of the Martian rocks, research into the internal structure of the planet, studying of its surface, atmosphere and climate.The paper briefly describes the penetrator design, the process of its landing and penetration into the Martian surface, items included in the complex scientific instrumentation and their specifications, and principal scientific tasks which can be realized with the use of penetrators.  相似文献   
32.
We examine the transformation of a gentle segmental to a meander loop with the result that the city, founded in the 17th century, found itself on the caving bank. Comparison of cartographic materials from different times showed the occurrence of secondary bends on elongated rectilinear wings. Not only did such an evolution of the meanders lead to the caving of the terraced urban bank, but also it involved a likely emergency situation on the underwater crossing of the pipeline, and on other engineering facilities. We ascertained the causes of the ongoing channel deformations; modeling data were used in developing recommendations on meander straightening in order to divert the river away from the city.  相似文献   
33.
Spectrograms and ELF power spectra of magnetic variations originated from sprite-producing lightning discharges have been analyzed to extract both parent lightning and sprite parameters. Some of the spectrograms and power spectra have been found to have approximately quasi-oscillatory shape in the frequency range 0–40 Hz with maximum repetition period about 15–20 Hz. A theory predicts that this interesting peculiarity of the power spectra can be due to interference between electromagnetic fields originated from the parent lightning discharge and from the sprite. A smooth envelope of the power spectrum was shown to have a form of damped oscillations with period close to reciprocal value of sprite lag time. A technique of extracting sprite parameters based on the sprite-producing lightning power spectrum is proposed. The lack of the first Schumann resonance and other features occasionally observed in spectral resonance structure were also discussed.  相似文献   
34.
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