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171.
Numerical simulations of energy depositions in the middle and upper solar chromosphere result in ejection of chromospheric material into the corona and heating of the chromospheric gas. These simulations may be capable of describing some of the features seen by the soft X-ray telescope on board theYohkoh satellite. 相似文献
172.
We highlight the effect on space-telescope temperatures of thedirectionality of the radiative properties of materials, by showing results from a Monte-Carlo simulation of telescope cooling. The need for further measurements of directional properties is stressed. 相似文献
173.
SWE,a comprehensive plasma instrument for the WIND spacecraft 总被引:1,自引:0,他引:1
K. W. Ogilvie D. J. Chornay R. J. Fritzenreiter F. Hunsaker J. Keller J. Lobell G. Miller J. D. Scudder E. C. Sittler Jr. R. B. Torbert D. Bodet G. Needell A. J. Lazarus J. T. Steinberg J. H. Tappan A. Mavretic E. Gergin 《Space Science Reviews》1995,71(1-4):55-77
The Solar Wind Experiment (SWE) on the WIND spacecraft is a comprehensive, integrated set of sensors which is designed to investigate outstanding problems in solar wind physics. It consists of two Faraday cup (FC) sensors; a vector electron and ion spectrometer (VEIS); a strahl sensor, which is especially configured to study the electron strahl close to the magnetic field direction; and an on-board calibration system. The energy/charge range of the Faraday cups is 150 V to 8 kV, and that of the VEIS is 7 V to 24.8 kV. The time resolution depends on the operational mode used, but can be of the order of a few seconds for 3-D measurements. Key parameters which broadly characterize the solar wind positive ion velocity distribution function will be made available rapidly from the GGS Central Data Handling Facility. 相似文献
174.
This study presents a methodology for specifying a neural controller for a system about which no a priori model information is available. The neural design presumes that a finite duration input/output (I/O) histogram on the system is available. The design procedure extracts from the histogram sufficient information to specify the neural feedback controller. The resultant controller will drive the system along a general output reference profile (unknown during the design). The resultant controller also exhibits the capability of disturbance rejection and the capacity to stabilize unstable plants 相似文献
175.
为达到IHPTET计划第三阶段目标,普惠公司进行了XTC67/1核心机试验。该公司在实施XTC67/1计划中取得了一些成果,但也存在一些问题 相似文献
176.
许多已经达到载客寿命的波音、空客和支线涡桨飞机都可以改装为货机,一个新兴的客改货市场正在形成。但客改贷项目的成功与否取决于飞机的改装费用和租金。 相似文献
177.
Kamide Y. Kihn E.A. Ridley A.J. Cliver E.W. Kadowaki Y. 《Space Science Reviews》2003,107(1-2):307-316
We report the recent progress in our joint program of real-time mapping of ionospheric electric fields and currents and field-aligned
currents through the Geospace Environment Data Analysis System (GEDAS) at the Solar-Terrestrial Environment Laboratory and
similar computer systems in the world. Data from individual ground magnetometers as well as from the solar wind are collected
by these systems and are used as input for the KRM and AMIE magnetogram-inversion algorithms, which calculate the two-dimensional
distribution of the ionospheric parameters. One of the goals of this program is to specify the solar-terrestrial environment
in terms of ionospheric processes, providing the scientific community with more than what geomagnetic activity indices and
statistical models provide.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
178.
Moore T.E. Collier M.R. Fok M.-C. Fuselier S.A. Khan H. Lennartsson W. Simpson D.G. Wilson G.R. Chandler M.O. 《Space Science Reviews》2003,109(1-4):351-371
Development of the low energy neutral atom (LENA) imager was originally motivated by a need to remotely sense plasma heating in the topside ionosphere, with the goal of greatly enhanced temporal resolution of an otherwise familiar phenomenon. During ground test and calibration, the LENA imager was found to respond to neutral atoms with energies well above its nominal energy range of 10–750 eV, up to at least 3–4 keV, owing to sputtering interactions with its conversion surface. On orbit, LENA has been found to respond to a ubiquitous neutral atom component of the solar wind, to the neutral atoms formed by magnetosheath interactions with the geocorona during periods of high solar wind pressure, and to the interstellar neutral atoms flowing through the heliosphere during the season of maximal relative wind velocity between spacecraft and interstellar medium. LENA imaging has thus emerged as a promising new tool for studying the interplanetary medium and its interaction with the magnetosphere, in addition to the ionospheric heating and outflow that result from this interaction. LENA emissions from the ionosphere consist of a fast component that can be observed at high altitudes, and slower components that evidently create a quasi-trapped extended superthermal exosphere. The more energetic emissions are responsive to solar wind energy inputs on time scales of a few minutes. 相似文献
179.
180.
R. Srama T. J. Ahrens N. Altobelli S. Auer J. G. Bradley M. Burton V. V. Dikarev T. Economou H. Fechtig M. Görlich M. Grande A. Graps E. Grün O. Havnes S. Helfert M. Horanyi E. Igenbergs E. K. Jessberger T. V. Johnson S. Kempf A. V. Krivov H. Krüger A. Mocker-Ahlreep G. Moragas-Klostermeyer P. Lamy M. Landgraf D. Linkert G. Linkert F. Lura J. A. M. McDonnell D. Möhlmann G. E. Morfill M. Müller M. Roy G. Schäfer G. Schlotzhauer G. H. Schwehm F. Spahn M. Stübig J. Svestka V. Tschernjawski A. J. Tuzzolino R. Wäsch H. A. Zook 《Space Science Reviews》2004,114(1-4):465-518
The Cassini-Huygens Cosmic Dust Analyzer (CDA) is intended to provide direct observations of dust grains with masses between 10−19 and 10−9 kg in interplanetary space and in the jovian and saturnian systems, to investigate their physical, chemical and dynamical properties as functions of the distances to the Sun, to Jupiter and to Saturn and its satellites and rings, to study their interaction with the saturnian rings, satellites and magnetosphere. Chemical composition of interplanetary meteoroids will be compared with asteroidal and cometary dust, as well as with Saturn dust, ejecta from rings and satellites. Ring and satellites phenomena which might be effects of meteoroid impacts will be compared with the interplanetary dust environment. Electrical charges of particulate matter in the magnetosphere and its consequences will be studied, e.g. the effects of the ambient plasma and the magnetic field on the trajectories of dust particles as well as fragmentation of particles due to electrostatic disruption.The investigation will be performed with an instrument that measures the mass, composition, electric charge, speed, and flight direction of individual dust particles. It is a highly reliable and versatile instrument with a mass sensitivity 106 times higher than that of the Pioneer 10 and 11 dust detectors which measured dust in the saturnian system. The Cosmic Dust Analyzer has significant inheritance from former space instrumentation developed for the VEGA, Giotto, Galileo, and Ulysses missions. It will reliably measure impacts from as low as 1 impact per month up to 104 impacts per second. The instrument weighs 17 kg and consumes 12 W, the integrated time-of-flight mass spectrometer has a mass resolution of up to 50. The nominal data transmission rate is 524 bits/s and varies between 50 and 4192 bps.This revised version was published online in July 2005 with a corrected cover date. 相似文献