The objective of this study is to propose the image quality correction method for the satellite multispectral image. Generally speaking, the deconvolution with MTF (Modulation Transfer Function) such as inverse filter, wiener filter and so on, has been used so often for the satellite multi-spectral image quality correction. But as for the satellite multi-spectral image quality correction, there are some problems about their accuracy and processing time. With the object of the simplicity of the algolithm and the adaptability to various kinds of satellite data, we proposed the RGS method (image Restoration method with Gauss-Seidel algolithm) for the image quality correction. The procedure of the correction is carried out by means of iterative tech-niques with Gauss-Seidel algolithm. Furthermore the 1D-RGS method (one Dimensional RGS method) is extended to the 2D-RGS method. Care must be taken that the 2D-RGS method is treated as the pseudo deconvolution in the strict sense (Burger and Cittert, 1932). In comparison with the restoration method using MTF, the results of this study are as follows : 1) It was found that the 2D-RGS method is one of the most superior method in image quality correction. Because, everyone can easily carry out the correction and get the same results. 2) It takes usually about an hour to make the color composite image with MTF, but only a few minutes with the 2D-RGS method and the operation efficiency is very high in image quality correction. 3) The 2D-RGS method can be easily carried out adjusting only two parameters called the instrumental function and the dumping factor. 4) As a result of applying the 2D-RGS method to MESSR, TM and HRV data respectively, it was found that the higher the resolution of satellite data, the more efficiently the 2D-RGS method can be carried out.
What is the horseshoe-shaped topographies in Kawashima-cho Hiki-gun seen on Landsat image? That is the origin of this study. This study is a good example that satellite remote sensing technoligy could have a potential to survey the large scale ruins of ancient river channel. This report describes the formation and valuation of the geographical characteristics in Kawashima-cho Saitama which are investigated by image analysis, surveying the literature, principal component analysis and numerical simulation of overland flood model. The results of this study are summarized as fol-lows : 1) The horeseshoe-shaped topographies are natural embankment which closely relate to the Arak-awa river channel of ancient times. In the present, these are used for road, field and residential area. 2) Principal component analysis using material datum of rainfall on and affter Meiji period indicate that amount of rainfall in upper stream from Yorii of The Arakawa river control the amount of flood damage in Kawashima-cho. Consequently, a. change of the Arakawa river channel in period Edo guided the amount of rainfall which determined flooded area and brought increasing of flood damage in Kawashima-cho. So it is necessary to give careful consideration to the design of improvement for river channel. 3) The result of numerical simulation of overland flood flow shows the horseshoe-shaped topographies work as embankmet against flood flow and lighten the flood damage. The natural embankmeent in seen on Landsat image defended residential and farm area against the overland flood flow of small scale.
The thermal belt is observed on two LANDSAT thermal images over and around the Kanto Plain, central Japan. The thermal belt is not a local phenomenon, but it extends over a large area at least several hundred kilometers. It can be obviously recognized in an image taken on 27/JAN./1987, but it is not in an image taken on 25/FEB./1986. The synoptic condition at each observation time may cause the difference in the extent of the thermal belt. In this paper, we report on the results of our investigation for the thermal belt using LANDSAT thematic mapper band 6 images and a digital terrain model. A LANDSAT thermal band image taken in 1987 was geometrically corrected to the latitude-longitude coordinate. Air temperatures at 68 mete-orological observation stations (AMeDAS) were compared with surface temperatures derived from LANDSAT CCT counts at the corresponding points. The equation to estimate air temperature at any pixel can be obtained with the correlation coefficient of 0.833. A LANDSAT thermal image in 1987 was super-imposed to a digital terrain model (KS110 in Digital National Land Information by the Geographic Survey Institute). Air temperatures on mountain slope show strong inversion. The top of the inversion layer is about 100 to 200m above the piedmont. Aerological observation data at Tateno Meteoro-logical Observatory at the time of LANDSAT-5 overpass show strong inversion of air temperature below 154m above the ground.This hight corresponds to the relative hight of the inversion at a mountain slope. Therefore the radiative cooling is closely related to the formation of thermal belt on a mountain slope. The distribution of wind direction and wind speed on 25, February 1986 implies that adiabatic warming of air blowing down the mountain slope may form the stable layer. Therefore the formation of the thermal belt is also connected with the wind as well as the atmospheric stability.
A 1.3 GHz pulse Doppler radar aiming at remote wind profiling of lower atmosphere from 100 m to 3 km heights above the ground has been developed by Communications Research Laboratory in 1990. The purpose of the development is to provide an unatten-dedly and continuously operational tool to observe wind profiles, which is useful for the reseaches of the boundary layer problems and pollutants transportation in the lower atmosphere. The system consists of a 3 m diameter parabolic antenna, a transmitter, a receiver, a Doppler signal processor, and controller/ data recording system. The capability of the system is confirmed by experimental measurements. In this paper, the radar system configuration, and the principle of wind measurement are first introduced, and then, the initial observation results are described. The initial observation results indicate the usefulness of the developed 1.3 GHz Doppler radar for wind profiling in the lower atmosphere under both fine and rainy weather conditions.