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531.
本文介绍针对固定温度点的热力学函数 (如焓、熵、比热 )综合近似计算法。该方法已成功地用来近似计算温度范围为 10 0~ 2 0 0 0 0 K的 150 0个热力学函数表。用内含近似计算程序包的 TD软件系统对混合物参数进行热力计算的结果证明,该多项式在求解多组元系统计算中迭代问题时具有很高的可靠性。 相似文献
532.
G. K. Parks C. Gurgiolo C. S. Lin K. A. Anderson R. P. Lin F. Martel H. Réme 《Space Science Reviews》1978,22(6):765-776
This article presents some of the new and important particle features that have been detected in the energy range 1 keV to 290 keV by the ISEE-1 and -2 spacecraft near the magnetopause, bow shock, and the interplanetary space. Only examples of data from the first few orbits, when the spacecraft were on the front side, are shown.Paper presented at 13th ESLAB Symposium, Innsbruck, Austria (June 5, 1978). 相似文献
533.
Dorr RF 《Aerospace America》2003,41(10):8-9, 41
Current legislative activity in Washington includes plans for hearings and proposed changes to NASA after the publication of the Columbia Accident Investigation Board report in August, 2003. Also reviewed are legislative interest in airline safety and armed forces expansion. 相似文献
534.
535.
R. Chandra P.F. Chen A. Fulara A.K. Srivastava W. Uddin 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2018,61(2):705-714
We present and discuss here the observations of a small long duration GOES B-class flare associated with a quiescent filament eruption, a global EUV wave and a CME on 2011 May 11. The event was well observed by the Solar Dynamics Observatory (SDO), GONG H, STEREO and Culgoora spectrograph. As the filament erupted, ahead of the filament we observed the propagation of EIT wave fronts, as well as two flare ribbons on both sides of the polarity inversion line (PIL) on the solar surface. The observations show the co-existence of two types of EUV waves, i.e., a fast and a slow one. A type II radio burst with up to the third harmonic component was also associated with this event. The evolution of photospheric magnetic field showed flux emergence and cancellation at the filament site before its eruption. 相似文献
536.
537.
C.F. Chen B.W. Reinisch J.L. Scali X. Huang R.R. Gamache M.J. Buonsanto B.D. Ward 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1994,14(12):43-46
At the Millstone Hill station the Incoherent Scatter Radar (ISR) and a Digisonde 256 are simultaneously operating. Some characteristic true heights determined by both instruments are compared with each other, possible reasons for observed difference are indicated. 相似文献
538.
Optimal and suboptimal guidance laws for short-range homing missiles are developed and compared to the commonly mechanized quidance law of proportional navigation. The optimal controller is derived as an optimal feedback regulator; the suboptimal controller is an approximation of the optimal regulator and consists of timevarying proportional navigation plus a time-varying gain term times a calculated target acceleration. Monte Carlo studies of the three controllers show that the optimal and suboptimal controllers are much superior to proportional navigation for the case of combined constant target acceleration, line-of-sight rate noise, and missile acceleration saturation. 相似文献
539.
Analysis of a typical amplitude-comparison monopulse angle-tracking radar shows that gain variation and bias in the radar error signal can occur under certain conditions involving multiple targets. The general behavior depends on the Doppler separation of the targets relative to system bandwidths; for a specific situation, the gain variation and bias are functions of the relative strengths of the targs. The analysis is shown to be consistent with experimental observations. 相似文献