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991.
I.V. Dorman L.I. Dorman 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
As many great discoveries, the phenomenon of cosmic rays was discovered mainly accidentally, during investigations that sought to answer another question: what are sources of air ionization? This problem became interesting for science about 230 years ago in the end of the 18th century, when physics met with a problem of leakage of electrical charge from very good isolated bodies. We describe the history how step by step cosmic rays was discovered and why this phenomenon received misnomer, how in cosmic rays was discovered the first antiparticle – positron. These discoveries were recognized among greatest in the 20th Century and were awarded by Nobel Prize. 相似文献
992.
E.I. Astafyeva E.L. Afraimovich A.V. Oinats Yu.V. Yasukevich I.V. Zhivetiev 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
We analyzed the dynamics of global electron content (GEC) for the period 1998–2005 and compared the estimated GEC with variations of the 10.7-cm solar radio emission and with and with GEC values obtained with IRI-2001. We found a strong resemblance between the curves’ shapes for the experimental and modeled GEC: strong semiannual variations are discernible in these series and both curves tend to increase the absolute GEC value during the period of maximum of solar activity. However, there are some significant distinctions, such as absence of 27-day fluctuations in the series of GEC computed by the IRI-2001. On the contrary, observational GEC reflects well dynamics of solar activity: 27-day variations of GEC are very similar to the ones of the index F10.7, but GEC undergoes a lagging of about of 30–60 h as compared to value of the F10.7 index. The relative amplitude of 27-day variations decreases from 8% at the rising and falling solar activity to 2% at the period of its maximum. 相似文献
993.
V. I. Garkushenko 《Russian Aeronautics (Iz VUZ)》2008,51(2):138-144
A problem of synthesizing the control laws for nonlinear nonstationary control systems by output being measured under uncertain external actions and nonlinearities that meet the sector constraints is considered. 相似文献
994.
995.
Yu.F. Gagarin A.M. Marenny R.A. Nymmik M.I. Panasyuk 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1998,21(12):1699-1702
Results of a detailed analysis of heavy ion fluences measured on the Salyut and MIR orbital stations from 1978 to 1990 are presented. The analysis has made use of new models that describe the cosmic ray fluxes and their transition through the magnetosphere. The penetration of solar cosmic ray particles to the orbit, the increase of the (ScCr)/Fe flux ratio in the orbit, and the occurrences of 200–500 MeV/nucl heavy nuclei in <30° latitudes have been analyzed. 相似文献
996.
A. I. Belousov Yu. K. Ponomarev Yu. N. Pronichev D. G. Krypaev 《Russian Aeronautics (Iz VUZ)》2009,52(2):201-207
The theory for calculating elastodamping characteristics of multilayer corrugated dampers being used in the rotor supports of aircraft gas turbine engines (GTEs), turbo-pump assemblies of rocket engines as well as in different articles of machine building industry is presented. 相似文献
997.
A. Krankowski I.I. Shagimuratov I.I. Ephishov A. Krypiak-Gregorczyk G. Yakimova 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
Simultaneous GPS observations from about 150 stations of European Permanent Network (EPN) have been used for studying dynamics of latitudinal profiles and structure of mid-latitude ionospheric trough (MIT). For the analyses, the TEC maps over Europe were created with high spatial and temporal resolution. The latitudinal profiles were produced from TEC maps with one-hour interval for geographic latitude range from 35N to 75N. The structure of latitudinal profiles relates to the occurrence of the ionospheric trough. The location of the trough depends on season, local time, and both geophysical and geomagnetic conditions. The trough structure in GPS-TEC demonstrates a smooth shape. The trough occurrence as a distinguished structure is more distinct during winter. The relation of TEC in the trough minimum to the equator and polar walls amounted to a factor of 2–4. 相似文献
998.
E.L. Afraimovich I.K. Edemskiy S.V. Voeykov Yu.V. Yasyukevich I.V. Zhivetiev 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009,44(7):824-835
Using long-term (1998--2009) total electron content (TEC) measurements from the GPS global network including dense network of GPS sites in USA and Japan, we have obtained the first data regarding the spatio-temporal structure and the statistics of medium-scale traveling wave packets (MS TWPs) excited by the solar terminator (ST). Total amount of the detected TWPs exceeds 565,000. There is no correlation between TWPs occurrence and geomagnetic and solar activity. We found that the diurnal, seasonal and spectral MS TWPs characteristics are specified by the solar terminator (ST) dynamics. MS TWPs are the chains of narrow-band TEC oscillations with single packet’s duration of about 1–2 h and oscillation periods of 10–20 min. The total duration of chain is about 4–6 h. The MS TWPs spatial structure is characterized by a high degree of anisotropy and coherence at the distance of more than 10 wavelengths. Occurrence rate of daytime MS TWPs is high in winter and during equinoxes. Occurrence rate of nighttime MS TWPs has its peak in summer. These features are consistent with previous MS travelling ionosphere disturbance (TID) statistics obtained from 630-nm airglow imaging observations in Japan. In winter, MS TWPs in the northern hemisphere are observed 3–4 h after the morning ST passage. In summer, MS TWPs are detected 1.5–2 h before the evening ST appearance at the point of observations, but at the moment of the evening ST passage in the magneto-conjugate point. The obtained results are the first experimental evidence for the hypothesis of the ST-generated ion sound waves. 相似文献
999.
A technique for calculating heat transfer characteristics of heat pipes equipped with isotropic-structure wicks made of the MR material is proposed and the investigation results are presented. 相似文献
1000.
In this paper, a technique for estimating the failure rate for GTE disks, taking into account the random failures, is presented. According to this technique, we analyzed the effect of tolerances for geometrical sizes, rotation frequency and disk material density on the failure rate. 相似文献