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181.
Sai F. Lee 《航空学报》1993,14(12):596-602
<正> The terrain profile at several airports has caused some difficulty with autolands on the DC-10 and MD-80. Some operators have reported that the pilot had to disconnect the flight guidance system during flare and land manually. At present, the autoland guidance system is not uniquely designed to handle the variations of terrain. Since there is no accurate substitute for radio altitude(h_(rad)) the only variable left to improve is radio altitude rate (h_(rad)). 相似文献
182.
M. Combes V. I. Moroz J. F. Crifo J. P. Bibring N. Coron J. Crovisier T. Encrenaz N. F. Sanko A. Grigoriev D. Bockele-Morvan R. Gispert C. Emerich J. M. Lamarre F. Rocard V. A. Krasnopolsky T. Owen 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1985,5(12):127-131
Results of the 2.5–5 micron spectroscopic channel of the IKS instrument on Vega are reported and the data reduction process is described. H2O and CO2 molecules have been detected with production rates of 1030 s−1 and 1.5 1028 s−1 respectively. Emission features between 3.3 and 3.7 microns are tentatively attributed to CH - bearing compounds - CO is marginally detected with a mixing ratio CO/H2O 0.2. OH emission and H2O - ice absorption might also be present in the spectra. 相似文献
183.
Tracking accuracies for the radial component of motion are computed for a track-while-scan radar system which obtains position and rate data during the dwell time on a target These results will be of interest to persons developing trackers for pulse Doppler surveillance radars. The normalized accuracies, computed for a two state Kalman tracking filter with white noise maneuver capability, are shown to depend upon two parameters, r = 4?0/?aT2 and s = ?dT/?0. The symbols ?0 and ?d are the position and rate measurement accuracies, respectively, ?a is the standard deviation of the white noise maneuver process and T is the antenna scan time. The scalar tracking filter equations are derived and numerical results are presented. Lower steady state tracking errors plus the earlier attainment of steady state accuracies are the direct consequence of incorporating the rate measurements into the tracking filter. 相似文献
184.
Castella F.R. Dunnebacke F.G. 《IEEE transactions on aerospace and electronic systems》1974,(6):891-895
A two-dimensional x, y Kalman tracking filter is analyzed for a track-while-scan (TWS) operation when the radar sensor measures range and bearing (r, ?) at uniform sampling intervals T seconds apart. This development explicitly considers the coupling between the quantities measured by the sensor (r, ?) and the Cartesian x, y coordinate system selected for the tracking operation. The steadystate components of the gain and error covariance matrixes are analytically determined under the assumption of a white noise maneuver acceleration model in two dimensions. These results are verified by computer calculation of the Kalman filter matrix equations. 相似文献
185.
The global network of meteorological satellites used different forms of international cooperation during its development, and some of these forms continue. Concern about continued operation of the global network led the WMO to study the issues and to adopt a long-term policy and strategy based on a shared meteorological satellite network. Nations need to consider how to combine their meteorological and space-related organizations in a partnership role, so they can directly contribute to a future global network of meteorological satellites. Some examples are cited to demonstrate that increased direct participation is a valid and feasible objective. 相似文献
186.
The goal of the Kinelite Project is to develop a space qualified motion analysis system to be used in space by the scientific community, mainly to support neuroscience protocols. The measurement principle of the Kinelite is to determine, by triangulation mean, the 3D position of small, lightweight, reflective markers positioned at the different points of interest. The scene is illuminated by Infra Red flashes and the reflected light is acquired by up to 8 precalibrated and synchronized CCD cameras. The main characteristics of the system are: Camera field of view: 45 degrees; Number of cameras: 2 to 8; Acquisition frequency: 25, 50, 100, or 200 Hz; CCD format: 256 x 256; Number of markers: up to 64; 3D accuracy: 2mm; Main dimensions: 45 cm x 45 cm x 30 cm; Mass: 23 kg; Power consumption: less than 200 W. The Kinelite will first fly aboard the NASA Spacelab; it will be used, during the NEUROLAB mission (4/98), to support the "Frames of References and Internal Models" (Principal Investigator: Pr. A. Berthoz, Co Investigators: J. McIntyre, F. Lacquaniti). 相似文献
187.
V. A. Komkov V. V. Vasilevskii V. F. Korolev Yu. V. Mozgovoi 《Russian Aeronautics (Iz VUZ)》2012,55(2):217-222
In this paper, a research and development version of the computer-aided system of mass tensometry (SMT) for conduction of aircraft and rocket-space equipment vibration tests is considered. A technique of the system design and development that combines the advantages of the system and process approaches when using the modern element base around the high-performance integral microcircuits is a distinctive feature in this research and development problem solution. We describe the architecture and structure of the advanced computer-aided SMTs and present data on its basic components desigtn. Also determined are the list and functional parameters of ratio-measuring network modules as well as the scheme of their connection to the test object and the local computer network of the enterprise. 相似文献
188.
F. De Tiberis L. Simone D. Gelfusa P. Simone R. Viola A. Santoni O. Cocciolillo M. Ziarelli F. Barletta N. Salerno M. Maffei V. Nanni 《Acta Astronautica》2011,68(5-6):591-598
This paper reports the main characteristics of the deep space transponder (DST) equipment that has been designed, developed and tested by Thales Alenia Space—Italy (TAS-I) for the European Space Agency (ESA) BepiColombo mission to Mercury. 相似文献
189.
190.