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61.
The scheme variants of implementing the thermal protection against heat flows being generated by the body of a high-temperature
stationary gas turbine engine (GTE) are presented. The scheme of the experimental bench with a working section is given. Methodical
approaches to the heat transfer calculation at different variants of forced and natural convection organization and under
various operating conditions are described. The generalized results of the experiments carried out using a heat curtain being
generated by porous injection are presented. 相似文献
62.
A mathematical model for the annular gas-liquid mixture flow in the cylindrical channel is described. The influence of an upward turbulent gas flow on the downward liquid film is considered. The problem is numerically solved and the calculation results are compared with the experimental data. 相似文献
63.
V. M. Gureev E. B. Matz Yu. F. Gortyshov R. R. Gel’manov 《Russian Aeronautics (Iz VUZ)》2008,51(4):447-451
A method for representing thermodynamic and thermophysical functions is presented; the functions make it possible to simulate thermal and gasodynamic processes in powerplants that use different individual substances or their mixtures as a working fluid. The method also involves consideration of real gas properties. 相似文献
64.
K. Yoshimura K. Abe H. Fuke S. Haino T. Hams M. Hasegawa A. Horikoshi K.C. Kim T. Kumazawa A. Kusumoto M.-H. Lee Y. Makida S. Matsuda Y. Matsukawa J.W. Mitchell A.A. Moiseev J. Nishimura M. Nozaki R. Orito J.F. Ormes K. Sakai M. Sasaki E.S. Seo Y. Shikaze R. Shinoda R.E. Streitmatter J. Suzuki K. Takeuchi N. Thakur K. Tanaka T. Yamagami A. Yamamoto T. Yoshida 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
65.
Y. Yamamoto T. Okada H. Shiraishi K. Shirai T. Arai K. Ogawa K. Hosono M. Arakawa M. Kato 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
The X-ray spectrometer (XRS) on the SELENE (SELenological and ENgineering Explorer) spacecraft, XRS, will observe fluorescent X-rays from the lunar surface. The energy of the fluorescent X-ray depends on the elements of which the lunar soil consists, therefore we can determine elemental composition of the upper most lunar surface. The XRS consists of three components: XRF-A, SOL-B, and SOL-C. XRF-A is the main sensor to observe X-rays from the lunar surface. SOL-B is direct monitor of Solar X-ray using Si-PIN photodiode. SOL-C is another Solar X-ray monitor but observes the X-rays from the standard sample attached on the base plate. This enables us to analyze by a comparative method similar to typical laboratory XRF methods. XRF-A and SOL-C adopt charge coupled device as an X-ray detector which depletion layer is deep enough to detect X-rays. The X-ray spectra were obtained by the flight model of XRS components, and all components has been worked well to analyze fluorescent X-rays. Currently, development of the hardware and software of the XRS has been finished and we are preparing for system integration test for the launch. 相似文献
66.
67.
Andrea D’Ambrosio Dario Spiller Fabio Curti 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2021,67(11):3462-3477
The development of fast and reliable optimization algorithms is required in order to obtain real-time optimal trajectory on-board spacecraft. In addition, the wide spread of small satellites, due to their low costs, is leading to a greater number of satellite formations in space. This paper presents an Improved version of the Magnetic Charged System Search (IMCSS) metaheuristic algorithm to compute time-suboptimal manoeuvres for satellite formation flying. The proposed algorithm exploits some strategies aimed at improving the convergence to the optimum, such as the chaotic local search and the boundary handling technique, and it is able to self-tune its internal parameters and coefficients. Moreover, the inverse dynamics technique and the differential flatness approach, through the B-splines curves, are used to approximate the trajectory. The optimization procedure is applied to the circular J2 relative model developed by Schweighart and Sedwick and to the elliptical relative motion model developed by Yamanaka and Ankersen. The results of this paper show that the convergence is better achieved by using the proposed tools, thus proving the efficiency and reliability of the algorithm in solving some space engineering problems. 相似文献
68.
A. B. Agul’nik I. V. Kravchenko A. A. Gorbunov A. A. Novoselova A. P. Sklyarova 《Russian Aeronautics (Iz VUZ)》2018,61(3):441-444
This paper considers double bypass aircraft engine with controlled air bleed to the second bypass duct. Its performance is evaluated by mathematical modeling techniques. The second bypass air bleed amount is determined to provide the best engine efficiency at various operating modes. 相似文献
69.
Lidar is one of the key sensors to understand global atmospheric environment, so lidar is one of the candidates to be flown on future earth observation satellites. But spaceborne lidar is our first trial and we have some technical issues to resolve before establishing operational sensor. So we start development of the Spaceborne Lidar Experimental Model as a first step of lidar program of NASDA. The Spaceborne Lidar Experimental Model will be launched in early 2001.
The purpose of the Spaceborne Lidar Experiment is technological demonstration of system design and critical components to apply to future operational sensor. And we demonstrate availability of lidar observation data and scientific value.
There are some critical points to resolve such as (1) thermal design of laser oscillator which remove locally-generated-heat effectively and (2) mirror design with little distortion. 相似文献
70.
Takashi Iida Kenichi Okamoto Yoshiaki Ohkami Seishiro Kibe Hajime Koshishi Masao Naka Hiromichi Yamamoto 《Acta Astronautica》1985,12(5):335-344
The large assembly antenna in space can meet future requirements of both high frequency and large aperture. This paper proposes an experiment on assembling a large antenna at the Space Station, and discusses a realizable procedure of the experiment. The objective of this experiment is that a large antenna of a 10-m diameter is assembled in space and at the same time problems occurring in the assembling process are clarified by conducting the following experiments: assembly of test articles by manipulators, measurement of both mechanical and electrical performance of the assembled antenna, test of the pointing control system, and operational test. In the operational test, the weather radar development test and the large aperture microwave radiometer development test are conducted. Furthermore, the problem areas and items of further study are discussed in this paper. 相似文献