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101.
Minakshi Devi A.K. Barbara Ko-Ichiro Oyama Chia-Hung Chen 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
The modifications induced in the dynamics of the ionosphere by the major Japan earthquake (EQ) of March 11, 2011 (epicenter at 38.322°N, 142.369°E, M = 8.9) in presence of a magnetic storm are examined by mapping latitudinal variations of F-layer ionization density (NmF2) from 22 stations covering the epicenter zone. The changes forced into the Total Electron Content (TEC) by the major EQ in the magnetic storm ambiance are also examined from the GPS data collected at Guwahati (26° 10′ N, 91° 45’ E), situated in the major fault system of East Asia. The contributions of pre-seismic electric field as well as of magnetic storm time electric field in the observed density variations are brought into the ambit of discussion. The influence of lower atmosphere in shaping TEC features during the study case is highlighted. The effects of solar activity on density variations during such complex ambiances are also addressed. 相似文献
102.
Oleg Novik Sergey ErshovYuri Ruzhin Fedor SmirnovMaxim Volgin 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
Due to the compound structure of the medium and large portions of energy transferred, a seismic excitation in the oceanic or continental lithosphere disturbs all types of geophysical fields. To investigate the problem of electromagnetic (EM) disturbances in the atmosphere from the seismically activated lithosphere, we have formulated two mathematical models of interaction of fields of different physical nature resulting in arising of the low-frequency (from 0.1 to 10 Hz by amplitude of a few hundreds of pT) EM signals in the atmosphere. First we have considered the EM field generation in the moving oceanic lithosphere and then in the moving continental one. For both cases, the main physical principles and geological data were applied for formulation of the model and characteristics of the computed signals of different nature agree with measurements of other authors. On the basis of the 2D model of the seismo-hydro-EM-temperature interaction in the lithosphere–Ocean–atmosphere domain, a block-scheme of a multisensory vertically distributed (from a seafloor up to the ionosphere) tsunami precursors’ detection system is described. On the basis of the 3D model of the seismo-EM interaction in a lithosphere–atmosphere domain, we explain why Prof. Kopytenko (Inst. IZMIRAN of Russian Acad. Sci.) and co-authors were able to estimate location of the future seismic epicenter area from their magnetic field measurements in the atmosphere near the earth’s surface. 相似文献
103.
H.C. Thejaswini Abhijit MajumdarTin Maung Tun Rainer Hippler 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
Plasma chemical reactions in C2H2/N2, C2H4/N2, and C2H6/N2 gas mixtures have been studied by means of mass spectrometry at a medium pressure of 300 mbar in a laboratory dielectric barrier discharge. A major reaction scheme is production of larger hydrocarbons like CnHm with n up to 12 including formation of functional CN groups. 相似文献
104.
Heiner Körnich Erich Becker 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
The interhemispheric coupling of the middle atmosphere general circulation is characterized by a global anomaly pattern of the zonal-mean temperature. This pattern reflects an anomalous stratospheric and mesospheric residual circulation, in which a weaker (stronger) stratospheric winter circulation is linked to an upward (downward) shift of its upper mesospheric branch reaching from the summer to the winter pole. This phenomenon is robust in observational data and several middle atmosphere general circulation models. In the present study, the recently proposed mechanism of the interhemispheric coupling is unequivocally proven within the framework of a zonally symmetric model that excludes any additional effects due to resolved waves and non-zonally propagating gravity waves. Two simulations are conducted that differ in the strength of the polar vortex. A weaker polar vortex results in a downward shift of the winter mesospheric gravity wave drag. This leads to changes also in the summer upper mesosphere via a feedback solely between gravity wave breaking and the zonal-mean state. The accompanying temperature anomaly reproduces the pattern of the interhemispheric coupling. 相似文献
105.
俞宝红 《华北航天工业学院学报》2002,12(4):46-48
本文主要从理论和实践的层面,论述以学生为中心的英语教学模式,教师发挥怎样的作用及发挥作用的主要途径。 相似文献
106.
直升机全量飞行动力学数值仿真模型及其实现 总被引:1,自引:0,他引:1
论述了一种通用的直升机飞行动力学全量数值仿真模型及其实现,该模型有6个机体自由度和3个旋翼自由度。以旋翼系统的仿真为重点,将直升机旋翼的气动力和力矩通过沿半径和方位角的解析积方求得,并计入了旋翼挥舞动力学的影响。仿真模型以某型直升机为算例,并加入了增稳系统,对仿真模型飞行特性进行了初步的验证,结果表明,所述模型思路是正确的。 相似文献
107.
Klaus Wilhelm Eckart Marsch Bhola N. Dwivedi Uri Feldman 《Space Science Reviews》2007,133(1-4):103-179
In Part I of this review, the concepts of solar vacuum-ultraviolet (VUV) observations were outlined together with a discussion
of the space instrumentation used for the investigations. A section on spectroradiometry provided some quantitative results
on the solar VUV radiation without considering any details of the solar phenomena leading to the radiation. Here, in Part
II, we present solar VUV observations over the last decades and their interpretations in terms of the plasma processes and
the parameters of the solar atmosphere, with emphasis on the spatial and thermal structures of the chromosphere, transition
region and corona of the quiet Sun. In addition, observations of active regions, solar flares and prominences are included
as well as of small-scale events. Special sections are devoted to the elemental composition of the solar atmosphere and theoretical
considerations on the heating of the corona and the generation of the solar wind. 相似文献
108.
109.
Robert J. Rutten 《Space Science Reviews》1998,85(1-2):269-280
This “rapporteur” report discusses the solar photosphere and low chromosphere in the context of chemical composition studies.
The highly dynamical nature of the photosphere does not seem to jeopardize precise determination of solar abundances in classical
fashion. It is still an open question how the highly dynamical nature of the low chromosphere contributes to first ionization
potential (FIP) fractionation.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
110.
Som Sharma V. Sivakumar H. Bencherif H. Chandra Y.B. Acharya A. Jayaraman P.B. Rao D. Narayana Rao 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2006,37(12):2278-II
The general characteristics of middle atmospheric thermal structure have been studied by making use of the Rayleigh lidar data collected over the period of about four years (1998–2001). Here, the data has been used from two different stations in the Indian sub-continent in tropics (Gadanki; 13.5°N, 79.2°E) and in sub-tropics (Mt. Abu; 24.5°N, 72.7°E). The observed monthly mean temperature profiles are compared with different model atmospheres (CIRA-86 and MSISE-90). We observed, the mean temperature profiles have closer agreement with MSISE-90 than CIRA-86. The temperature profiles measured by lidar and HALOE satellite overpass nearby lidar site are generally in agreement with each other. The systematic and statistical errors in deriving temperature are found to be uniform for both the stations, as 1 K at 50 km, 3 K at 60 km and 10 K at 70 km. The special features of mesospheric temperature inversion (MTI) and double stratopause structure (DBS) are also addressed for both the stations. 相似文献