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691.
692.
S. I. Solovyev V. A. Mullayarov D. G. Baishev E. S. Barkova S. N. Samsonov 《Cosmic Research》2004,42(6):607-613
Modulation of the VLF emission and riometric absorption by Pc5 geomagnetic pulsations is studied in the period of strong geomagnetic disturbances on October 30–31, 2003. Some conclusions about the regime of pitch-angular diffusion into the loss cone are made. The better coincidence of VLF emission modulation with geomagnetic pulsations in other longitude sectors is explained by the global character of excitation of the pulsations and by damping of their amplitudes at the meridian of observation of the VLF emission, which is associated with intensification of auroral electrojets.Translated from Kosmicheskie Issledovaniya, Vol. 42, No. 6, 2004, pp. 632–639.Original Russian Text Copyright © 2004 by Solovyev, Mullayarov, Baishev, Barkova, Samsonov. 相似文献
693.
Shun Liu Hagiwara H. Shoji R. Tamara H. Okano T. 《Aerospace and Electronic Systems Magazine, IEEE》2004,19(11):3-11
A complete grasp of the actual vessel traffic flow by accurate observation is essential to carry out vessel traffic management, design of vessel traffic route, plan of port construction, etc. Up to now, the observation of vessel traffic has needed many efforts such as the use of a special ship or car equipped with radar observation systems and the observation staff preparation for a considerably long period. In order to perform accurate observation of vessel traffic without such efforts, the authors have developed a completely automated radar network system covering the main traffic route of Tokyo Bay. In August 2003, as the second remote radar station attaching AIS equipment was set at East Ogishima (the first was installed at the National Defense Academy in 2002), the observing range could be enlarged and cover most traffic routes in Tokyo Bay. These two radars can observe the vessel traffic in Tokyo Bay simultaneously so as to know the traffic flow accurately on the basis of analyzing the integrated radar data. In addition to the development of a radar network system, the software to analyze observed vessel traffic flow has been developed. This software has various functions such as tracking of ship's position, automatic determination of ship's size, animation of ship's movements, superposition of successive radar images, display of ship's tracks, calculation of ship's speed distribution, extraction of dangerous ship encounters using subjective judgment value and bumper model, etc. Some analyzed results on vessel traffic flow observed by the remote radars in January and September 2003 are shown in this paper. 相似文献
694.
Spatial structure of the magnetosheath of the Earth was studied under the conditions when no sharp (more than 40° during 5
min) changes in the interplanetary magnetic field direction were observed. On the basis of 24 flights of the Interball-1 satellite through the magnetosheath, it is found that three regions differing from each other by parameters of the field
and plasma can be observed in the magnetosheath under the above-indicated conditions. These regions also differ from the solar
wind region before front of the Earth’s magnetospheric bow shock. Empirical distributions of parameters were studied in each
region. Taking into account the influence of the interplanetary magnetic field direction on the processes in the magnetosheath,
the cases of quasi-perpendicular and quasi-parallel shock waves were considered separately. The study showed that the distribution
of parameters in the selected regions (in the solar wind before front of the bow shock, in the magnetosheath behind the bow
shock (post-shock), in the region of the magnetosheath with minimal fluctuations in the field, and in the inner magnetosheath)
differ from each other at any interplanetary magnetic field direction. 相似文献
695.
A. N. Denisov N. V. Kuznetsov R. A. Nymmik M. I. Panasyuk N. M. Sobolevskii 《Cosmic Research》2010,48(6):509-516
In connection with projects of manned bases on the Moon it becomes topical to estimate radiation danger for their inhabitants.
In this paper we describe a method of evaluation of the radiation environment on the lunar surface produced by galactic and
solar cosmic rays. The roles of both primary and secondary radiations generated in the depth of the lunar soil under the action
of high-energy protons and nuclei are taken into account. Calculated fluxes of particles are used in order to estimate annual
averaged absorbed and equivalent local dose rates in tissues. It is established that in the lunar rock the contribution of
secondary neutrons to the dose rate exceeds that of protons. The contribution of the secondary particles generated by nuclei
of galactic cosmic rays to the dose rate is estimated. 相似文献
696.
V. Génot C. Jacquey M. Bouchemit M. Gangloff A. Fedorov B. Lavraud N. André L. Broussillou C. Harvey E. Pallier E. Penou E. Budnik R. Hitier B. Cecconi F. Dériot D. Heulet J.-L. Pinçon 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
AMDA (Automated Multi-Dataset Analysis), a new data analysis service, recently opened at the French Plasma Physics Data Center (CDPP). AMDA is developed according to the Virtual Observatory paradigm: it is a web-based facility for on-line analyses of space physics. Data may come from its own local database as well as remote ones. This tool allows the user to perform classical manipulations such as data visualization, parameter computation and data extraction. AMDA also offers innovative functionalities such as event searches on the content of the data in either visual or automated ways, generation, use and management of time tables (event lists). The general functionalities of AMDA are presented in the context of Space Weather with example scientific use cases. 相似文献
697.
V. G. Gainutdinov 《Russian Aeronautics (Iz VUZ)》2010,53(3):277-282
An algorithm is proposed for computer-aided calculation of required values of aircraft controlling moments and aerodynamic
moment coefficients for stable fulfillment of flight trajectories specified by design flight performance. 相似文献
698.
C.J. Hailey T. Aramaki S.E. Boggs P.v. Doetinchem H. Fuke F. Gahbauer J.E. Koglin N. Madden S.A.I. Mognet R. Ong T. Yoshida T. Zhang J.A. Zweerink 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
The General Antiparticle Spectrometer (GAPS) is a new approach to the indirect detection of dark matter. It relies on searching for primary antideuterons produced in the annihilation of dark matter in the galactic halo. Low energy antideuterons produced through Standard Model processes, such as collisions of cosmic-rays with interstellar baryons, are greatly suppressed compared to primary antideuterons. Thus a low energy antideuteron search provides a clean signature of dark matter. In GAPS antiparticles are slowed down and captured in target atoms. The resultant exotic atom deexcites with the emission of X-rays and annihilation pions, protons and other particles. A tracking geometry allows for the detection of the X-rays and particles, providing a unique signature to identify the mass of the antiparticle. A prototype detector was successfully tested at the KEK accelerator in 2005, and a prototype GAPS balloon flight is scheduled for 2011. This will be followed by a full scale experiment on a long duration balloon from Antarctica in 2014. We discuss the status and future plans for GAPS. 相似文献
699.
C. P. T. Groth D. L. De Zeeuw T. I. Gombosi K. G. Powell 《Space Science Reviews》1999,87(1-2):193-198
A parallel adaptive mesh refinement (AMR) scheme is described for solving the governing equations of ideal magnetohydrodynamics
(MHD) in three space dimensions. This solution algorithm makes use of modern finite-volume numerical methodology to provide
a combination of high solution accuracy and computational robustness. Efficient and scalable implementations of the method
have been developed for massively parallel computer architectures and high performance achieved. Numerical results are discussed
for a simplified model of the initiation and evolution of coronal mass ejections (CMEs) in the inner heliosphere. The results
demonstrate the potential of this numerical tool for enhancing our understanding of coronal and solar wind plasma processes.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
700.
This paper describes a system of navigation by measurement of the Doppler shift in the radio transmissions from a near-Earth satellite, and simple equipment for making the measurements. It also shows that the current information which is needed by the navigator can be reduced to a number containing six decimal digits. Finally, it shows that the computations needed for the navigator to obtain a fix can be performed witlh the aid of tables that can be prepared at least 18 months in advance. Using these tables and a simple slide rule, but no other computational aids, a fix accurate to about 500 meters can be obtained in about 10 minutes. More accuracy can be obtained at the expense of time, or time can be saved at the expense of accuracy. 相似文献