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981.
K.J. Lee G.J. Qiao H.G. Wang R.X. Xu 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(1):180-182
The electric properties of pulsar’s inner annular gap are explored in this paper. Under two main assumptions, (1) the pulsar is alive, (2) the total charge of pulsar should not vary with time, the condition for the acceleration of negative particle in the annular region is derived. The acceleration condition is j− ? 0.5j+, i.e., the current carried by negative particles is greater than or equal to 0.5 times of the current carried by positive particles. This condition holds even when the backward flow of positive particles exists in the annular region. It is noted that the outflow of negative particles offers good opportunities to understand the current closure problem of pulsar as well as wide radiation beam of pulsar observed at high energy band. 相似文献
982.
Hydrogenated amorphous Si (a-Si:H) devices first made a significant impact in photovoltaic application, 70% of the photovoltaic solar cells produced in Japan in 1984 were a-Si:H. More recently, thin film transistor (TFT) and sensor devices have been developed for consumer and business products. The ability to produce large area uniform films of a-Si:H makes the application of TFTs and sensors well suited for input and output imaging devices such as image scanners, display and printers. This paper reviews the operation, material issues and physics of a-Si:H TFTs and sensors. The circuit and technology issues in large area systems incorporating these devices are described. 相似文献
983.
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
984.
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
985.
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
986.
Cosmic radiation has been measured by a variety of techniques since 1933. This paper presents the evolution of data acquisition,
processing, and availability of cosmic radiation data from the early years to the present time. Information on the worldwide
network of neutron monitor stations and the availability of these cosmic radiation records is included.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
987.
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
988.
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
989.
A three-dimensional design model of a helicopter tubular skid landing gear based on the application of the large beam displacement
theory is presented. The design model takes into account special features of constructive, physical and geometrical deformation
nonlinearity. The analysis of a real helicopter structure is given that confirms sufficient validity of calculation results
obtained using the model developed by comparing with the results of the finite element analysis. 相似文献
990.
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