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151.
A generalized problem of two fixed centers and its limiting version is considered. New possible applications of this problem are obtained. Using a symmetric version of the problem, the external field of gravitation is approximated. The limiting version approximates the inner field. 相似文献
152.
As a result of processing long (up to 144 h) series of sunspot magnetograms obtained on the SOHO (Solar and Heliospheric Observatory) spacecraft with the MDI (Michelson Doppler Imager) instrument it is shown that the mode
with a period of 800–1300 min is a limiting low-frequency oscillation mode of the magnetic field of a sunspot as a whole.
Its period is essentially and nonlinearly depends on the sunspot magnetic field strength. In addition to this mode, higher
harmonics are also revealed in the sunspot oscillation spectra in the bands 40–45, 60–80, 135–170, 220–250, and 480–520 min.
The oscillation power in these bands monotonically and rapidly decreases with increasing frequency, which is characteristic
for overtones arising due to the nonlinear nature of oscillations. The limiting oscillation mode stably exists in sunspots
for 1.5–2 days, which coincides with the average lifetime of a supergranular cell. The mode with the period of 35–48 h observed
in the power spectrum is not an eigen mode of sunspots, because its period is independent of its magnetic field strength.
Probably, it occurs as a quasiperiod of an external exciting force caused by disturbances from supergranular cells surrounding
the sunspot. 相似文献
153.
H. E. Spence G. D. Reeves D. N. Baker J. B. Blake M. Bolton S. Bourdarie A. A. Chan S. G. Claudepierre J. H. Clemmons J. P. Cravens S. R. Elkington J. F. Fennell R. H. W. Friedel H. O. Funsten J. Goldstein J. C. Green A. Guthrie M. G. Henderson R. B. Horne M. K. Hudson J.-M. Jahn V. K. Jordanova S. G. Kanekal B. W. Klatt B. A. Larsen X. Li E. A. MacDonald I. R. Mann J. Niehof T. P. O’Brien T. G. Onsager D. Salvaggio R. M. Skoug S. S. Smith L. L. Suther M. F. Thomsen R. M. Thorne 《Space Science Reviews》2013,179(1-4):311-336
154.
Luca D’Acci 《Spatial Cognition & Computation》2019,19(3):172-189
Current topological and geometrical distances in Space Syntax are based on the premise that each change of direction along a path is a mental cost because one loses orientation. This paper proposes to extend the analysis to the case in which esthetic and variety, rather than orientation, are the key elements of street selection. It is widely recognized that most people are attracted to curvy paths rather than straight ones; therefore, when one is not worried about losing orientation in her walk, or when the preferred path is well recognizable even when it requires changes of direction, we should adopt another criterion to weigh distances: morphoahestetic and networkvariety criteria are shown as potential parameterization for Space Syntax distances. 相似文献
155.
M.?Yu.?OvchinnikovEmail author V.?I.?Pen’kov D.?S.?Roldugin S.?O.?Karpenko 《Cosmic Research》2012,50(2):170-176
We consider the rapid rotation of a satellite equipped with an active magnetic attitude control system with the -Bdot algorithm designed to damp the initial angular velocity. The time-response of the algorithm is analytically studied as a
function of orbit inclination. 相似文献
156.
M. I. Panasyuk S. I. Svertilov V. V. Bogomolov G. K. Garipov V. O. Barinova A. V. Bogomolov N. N. Veden’kin I. A. Golovanov A. F. Iyudin V. V. Kalegaev P. A. Klimov A. S. Kovtyukh E. A. Kuznetsova V. S. Morozenko O. V. Morozov I. N. Myagkova V. L. Petrov A. V. Prokhorov G. V. Rozhkov E. A. Sigaeva B. A. Khrenov I. V. Yashin S. I. Klimov D. I. Vavilov V. A. Grushin T. V. Grechko V. V. Khartov V. A. Kudryashov S. V. Bortnikov P. V. Mzhel’skiy A. P. Papkov S. V. Krasnopeev V. V. Krug V. E. Korepanov S. Belyaev A. Demidov Ch. Ferenz L. Bodnar P. Szegedi H. Rotkel M. Moravskiy Il Park Jin-A Jeon Ji-In Kim Jik Lee 《Cosmic Research》2016,54(5):343-350
We present the first experimental results on the observation of optical transients, gamma-ray bursts, relativistic electrons, and electromagnetic waves obtained during the experiment with the RELEC complex of scientific equipment on the Vernov satellite. 相似文献
157.
L. O’C. Drury D.E. Ellison F.A. Aharonian E. Berezhko A. Bykov A. Decourchelle R. Diehl G. Meynet E. Parizot J. Raymond S. Reynolds S. Spangler 《Space Science Reviews》2001,99(1-4):329-352
The main features of cosmic-ray source models and acceleration processes are reviewed, with special emphasis on the possible observational tests, through both composition analysis and multi-wavelength studies of supernova remnants. Non-linear effects in the context of supernova-induced diffusive shock acceleration are discussed, as well as collective acceleration effects induced by multiple supernova explosions inside superbubbles. 相似文献
158.
I. G. Mitrofanov M. L. Litvak A. B. Varenikov Y. N. Barmakov A. Behar Y. I. Bobrovnitsky E. P. Bogolubov W. V. Boynton K. Harshman E. Kan A. S. Kozyrev R. O. Kuzmin A. V. Malakhov M. I. Mokrousov S. N. Ponomareva V. I. Ryzhkov A. B. Sanin G. A. Smirnov V. N. Shvetsov G. N. Timoshenko T. M. Tomilina V. I. Tret’yakov A. A. Vostrukhin 《Space Science Reviews》2012,170(1-4):559-582
159.
The concept and definition of integrated flight performance for a small remotely piloted helicopter are introduced to obtain real operational values in performing a flight mission. 相似文献
160.
Proceeding from the first assumption of kinetic-molecular theory, the authors propose the Toms effect on reducing the hydrodynamic drag in a turbulent flow with polymer additives and its usage in power plants, to be explained. 相似文献