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971.
V. Tamilarasan S.K. Sharma S.R. Nagabhushana 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(2):287-290
An experiment was undertaken to select the optimum spectral bands for the discrimination of land use/cover for proposed Indian Remote Sensing Satellite. A feature selection method was used for the discrimination analysis on the multiband data collected by Bendix 11-channel Modular Multiband Scanner over Tirupati test site of Chittoor district, Andhra Pradesh, South India. Of the various combinations of bands analysed, the optimum combination of four bands was defined as that one which provided the greatest divergence distances to discriminate the specific land covers in the test sites. On the basis of the above studies the optimum bands so chosen are 0.49–0.54 μm, 0.62–0.66 μm, 0.66–0.70 μm and 0.77–0.86 μm. 相似文献
972.
K. Sezaki S. Enya M. Morioka J. Ochiai I. Tanasawa T. Maekawa 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(5):85-88
In this paper, the Marangoni convection including buoyancy convection in two-dimensional fluid model was investigated experimentally and theoretically. The transparent liquid in the test cell was heated and cooled under various conditions. The fluid flow driven by surface tension and by buoyancy force was visualized and measured. The flow patterns, velocity distributions and temperature field were obtained and they were compared with the results of the numerical solutions. The effect of the configuration and the convection in microgravity on crystal growth was discussed. The temperature field of the crystallizing surface was predicted. 相似文献
973.
A new open-loop adaptive-array system with excellent transient behavior is presented. The system is constructed of analog circuits and determines complex weights without using the feedback of the array output. The performance attainable with the system is described in detail. It is shown that the convergence rate of the system does not depend on a noise environment but is determined by the time constant of the low-pass filters included. Moreover, it is shown that although the steady-state performance is quite good when the interference sources differ widely in signal strength, the steady-state performance can be far below optimum when two or more interference sources are present at roughly equal power levels. 相似文献
974.
Ramachandra K.V. Division R.C. 《IEEE transactions on aerospace and electronic systems》1983,(5):776-778
Analytical results are presented for determining the steady-state components of the gain and error covariance matrices of the two-state Kalman tracking filter with white noise maneuver capability. 相似文献
975.
976.
977.
K.L. Majumder R. Ramakrishnan I.C. Matieda G. Sharma A.K.S. Gopalan D.S. Kamat 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(2):283-286
Indian Space Research Organisation (ISRO) plans to launch a Remote Sensing Satellite around 1985 for acquiring resources information in the visible and near infrared region. For this a number of projects under Joint Experiments Program (JEP) were taken up between ISRO and various departments under Government of India to define the mission parameters including the spectral bands. This paper presents the results obtained in the selection of spectral bands and their widths for IRS program. 相似文献
978.
K. Bischoff E. Orlicek K.-H. Schmelovsky G. Zimmermann J. Gatzke J. Wiegmann 《Acta Astronautica》1983,10(1):31-35
First results are presented of technical tests of a Data Collection System and a multispectral remote sensing complex. The aim of this experiment is to test the hard ware for in situ and remote sensing data collection of oceanographic parameters. 相似文献
979.
980.
R.C. Smith K.S. Baker 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(9):123-133
Estimates of global marine primary productivity are currently based upon the 14C method for determining rates of plankton photosynthesis and upon the relatively sparse data available using shipboard sampling techniques. With recent advances in remote sensing and in multiplatform (ship, aircraft, and satellite) sampling strategies, it is now possible to significantly lower the variance in estimates of phytoplankton abundance and of population growth rates.Multiplatform sampling strategies are essential to assess the mean and variance of phytoplankton biomass on a regional or on a global basis. The relative errors associated with shipboard and satellite estimates of phytoplankton biomass and primary productivity, as well as the increased statistical accuracy now possible from the utilization of contemporaneous data from both sampling platforms, are discussed. It is shown that one of the more exciting and potentially useful aspects of oceanographic research today is our new ability to view large areas of the ocean synoptically. 相似文献