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991.
J.T. Rudd D.M. Oliveira A. Bhaskar A.J. Halford 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2019,63(1):317-326
In this paper, we investigate temporal and spatial magnetosphere response to the impact of interplanetary (IP) shocks with different inclinations and speeds on the Earth’s magnetosphere. A data set with more than 500 IP shocks is used to identify positive sudden impulse (SI+) events as expressed by the SuperMAG partial ring current index. The SI+ rise time (RT), defined as the time interval between compression onset and maximum SI+ signature, is obtained for each event. We use RT and a model suggested by Takeuchi et al. (2002) to calculate the geoeffective magnetospheric distance (GMD) in the shock propagation direction as a function of shock impact angle and speed for each event. GMD is a generalization of the geoeffective magnetosphere length (GML) suggested by Takeuchi et al. (2002), defined from the subsolar point along the X line toward the tail. We estimate statistical GMD and GML values which are then reported for the first time. We also show that, similarly to well-known results for RT, the highest correlation coefficient for the GMD and impact angle is found for shocks with high speeds and small impact angles, and the faster and more frontal the shock, the smaller the GMD. This result indicates that the magnetospheric response depends heavily on shock impact angle. With these results, we argue that the prediction and forecasting of space weather events, such as those caused by coronal mass ejections, will not be accurately accomplished if the disturbances’ angles of impact are not considered as an important parameter within model and observation scheme capabilities. 相似文献
992.
V. A. Sorokin N. N. Zakharov M. S. Sharov L. S. Yanovskii 《Russian Aeronautics (Iz VUZ)》2010,53(3):295-302
The results of experimental investigations of gasodynamic characteristics of a combustion chamber model in the integrated power plant (IPP) with an asymmetric air intake are presented. The influence of an angle of air supply into the chamber model on hydraulic losses and the flow structure is shown at different air flowrates, relative values of the minimal flow section area of the feeding air intake pipes, under changes of the flowrate of gas simulating gas generation products and geometric model parameters. A technique for measuring the concentration of carbon dioxide simulating IPP gas generation products in the combustion chamber air flow and the results of experimental investigations of a mixture formation process in the combustion chamber model are described. 相似文献
993.
S. Mereghetti A. Tiengo P. Esposito G. Vianello A. De Luca D. Götz G. Weidenspointner A. von Kienlin G.L. Israel L. Stella N. Rea R. Turolla S. Zane 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
We describe the results obtained with Target of Opportunity observations of the galactic sources SGR 1627–41 and 1E 1547–5408. These two transients show several similarities supporting the interpretation of Anomalous X-ray Pulsars and Soft Gamma-ray Repeaters as a single class of strongly magnetized neutron stars. 相似文献
994.
A technique of optimizing the electrode system of the differential recorder for the aircraft time-of-flight ion-marking airspeed and aircraft angle of attack sensor by the criterion of ion-marking recording error variance minimum is considered. The technique is based on analyzing the function of spatial distribution for the ion-marking and recorder electrode interaction field potential and determining a point for which this function reaches the maximum slope. The relations making it possible to synthesize the sensor electrode system by the complex criterion as a ratio of error variance to transformation channel response are obtained. 相似文献
995.
A.?I.?Efimov "mailto:efimov@ms.ire.rssi.ru " title= "efimov@ms.ire.rssi.ru " itemprop= "email " data-track= "click " data-track-action= "Email author " data-track-label= " ">Email author L.?A.?Lukanina I.?V.?Chashei S.?F.?Kolomiets M.?K.?Bird M.?P?tzold 《Cosmic Research》2018,56(1):1-10
In 2013 and 2015, investigations of the internal solar wind were carried out using the method of two-frequency radio sounding by signals from the Mars Express European spacecraft. The values of the S- and X-bands’ frequency and the differential frequency were registered with a sampling rate of 1s at the American and European networks of ground-based tracking stations. The spatial distribution of the frequency fluctuation’s level has been studied. It has been shown that the intensity of frequency fluctuation considerably decreases at high heliolatitudes. In some radio sounding sessions, quasiperiodic oscillations of sub-mHz band have been observed in the temporal spectra of frequency fluctuations; they are supposed to be associated with the density inhomogeneities, the sizes of which are close to the turbulence outer scale. 相似文献
996.
A. V. Tavrov O. I. Korablev A. V. Rodin I. I. Vinogradov A. Yu. Trokhimovsky A. Yu. Ivanov L. V. Ksanfomaliti D. A. Orlov 《Cosmic Research》2011,49(2):99-109
In order to observe exoplanets we propose a space-based achromatic stellar coronagraph combined with a 0.8–1.5 m telescope. We develop an achromatic common path interferometer for observing an exoplanet (a faint off-axis source) on the background of a hoste star (bright axial source). An image of the star and its copy acquire an achromatic phase shift by 180° and interfere in antiphase. The achromatic phase shift is caused by geometric phase in the scheme of a three-dimensional interferometer. The interference process divides spatially the dark and light fields of the star image redirecting them to the opposite sides of a beam splitter. The interference process does not weaken the image of a planet, with equal intensities it is redirected to both sides of a beam splitter. The suggested scheme of common path interferometer ensures mechanical stability. The background signal is experimentally demonstrated to be reduced by six orders of magnitude. 相似文献
997.
I. A. Galiullin 《Cosmic Research》2011,49(2):175-178
The constraints imposed on parameters of a force field and of a symmetrical gyrostat in it are determined, at which regular precession of this gyrostat demonstrate Lyapunov stability (or, respectively, instability). 相似文献
998.
V.?A.?Afanas’ev G.?L.?Degtyarev A.?S.?Meshchanov "mailto:mas@list.ru " title= "mas@list.ru " itemprop= "email " data-track= "click " data-track-action= "Email author " data-track-label= " ">Email author 《Russian Aeronautics (Iz VUZ)》2018,61(1):23-31
Real values of parameters for a space vehicle and its steering devices are specified by using the motion parameters measured in flight based on solving the differential equations of motion. 相似文献
999.
A. C. Fabian 《Space Science Reviews》1999,89(3-4):692-693
We see neutron stars principally by their radio and X-ray emission. Their appearance in these different bands depends on whether
the emission comes from the surface or its magnetosphere. New phenomena continue to be found from neutron stars, which makes
it an exciting and topical research area. This volume is a collection of the papers from a NATO Advanced Study Institute held
in Italy in October 1996. Many, and for me the most interesting ones, are substantial reviews on topics such as Pulsar magnetic
fields and glitches (M. Ruderman), Radio pulsar population properties (D. Lorimer), Gamma-ray emission from CGRO pulsars (G.
Kanbach), Neutron stars and black holes in X-ray binaries (J. van Paradijs), Kilohertz quasi-periodic oscillations in low-mass
X-ray binaries (M. van der Klis), Thermonuclear burning on rapidly accreting neutron stars (L. Bildsten), On the X-ray emission
properties of rotation powered pulsars (W. Becker and J. Truemper). It will serve as a useful reference and source book for
students in high energy astrophysics and related fields. The high price may deter its purchase by individuals, but it will
be a good volume for a library needing recent coverage on neutron stars. It does not of course include the most recent developments
on anomalous X-ray pulsars or magnetars.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
1000.
Basic design guidelines are presented for a three-phase tubular linear alternator (LA). A numerical example for the design of a 25 kVA, 14.4 mls, 120/220 V, 60 Hz alternator is used to illustrate the procedure. 相似文献