The objective of this study is to determine two parameters (instrument function, damping factor) in the RGS-method (the image restoration method with Gauss-Seidel algorithm) as a image quality improvement method, which was published in the Journal of the Remote Sensing Society of Japan in 1992. The RGS-method can be easily carried out adjusting only two parameters for the satellite multispectral image of various quality. As a present procedure, two parameters are determined through the simulation for image quality improvement using RGS-method. But a satellite multispectral image shows various quality, it is important to know how to decide the value of parameters before the image improvement processing.
Recently, it is reported that the fluctuation index used in the fluctuation theory is useful for analysing correlation of visual complexity or human mind etc. First of all, the applicability of the fluctuation index for determining two parameters was investigated.
According to the examination for MESSR. TM and HRV data, in the case the image quality is good, a very interesting result was shown that the scatter of the points on the scatter diagram of the power spectrum gives essentially straight line. Further investigation was carried out to clear the causality between the image quality and linearity measure in the scatter diagram.
The procedures for determination of two parameters consist of four steps as follows:
STEP-1) Simulation of image quality improvement using RGS-method.
STEP-2) Determination of damping factor (Df) by means of fluctuation index.
STEP-3) Determination of damping factor (D1) by means of linearity measure.
STEP-4) Decision of damping factor by taking the average value between D, and Df. The results of this study are as follows:
1) The fluctuation index as the gradient for the power spectrum is calculated. Damping factor (Df) can be decided just in case the value of fluctuation index is changed remarkably, because at this time, it was confirmed that the spectral feature of improved image is not preserved.
2) As a results of the examination on the scatter of the power spectrum, the linearity measure shows a change of local spatial frequency feature. Damping factor (D₁) could be decided by means of the maximum value for linearity measure.
3) When the image quality is good, it was confirmed that the value of damping factor is between D₁ and D_f Based on this result, damping factor is decided by taking the average value between D₁ and D_f. In conclusions, it was shown that parameters of RGS-method can be set automatically on the computer processing.

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A laser ranging system that can observe the topographical structure of a volcano body has been developod. This system transmits laser toward a target and receive reflected light and render the three-dimensional topographical structure of a volcano body with approximately 30 cm accurecy. Although this accuracy is worse than that of a normal laser ranging system which uses a corner-cube reflector due to the jitter of reflected light caused by the inclination and unevenness of the target ground surface, it is still usefull to grasp a sign of a deformation of topographcal features where placement of reflector is very difficult. The system design and preliminay field test results obtained at Bandai volcano are reported.

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Satellite remote sensing images allow us to discriminate and extract detailed topographic features of the earth. SPOT HRV multispectral images remarkably give us higher resolution for lineament extraction.
This paper is aimed to clarify the optimum local operators for image analysis using extracted lineaments from HRV multispectral data. We made an experiment in relation to various types of digital filter such as median (md3, md 5), monodirectional high frequency component enhancement (tt3, tt5, ty3, ty5), slantdirectional high frequency component enhancement (nm 3, nm 5), bidirectional high frequency compo-nent enhancement (ty3, ty5), and omnidirectional high frequency component enhancement (om3, om5) applying to enhance the selected two images of mountainous area in Tohoku district. We generated 12 images in each area to extract the lineaments that show the direction of subsurface fractures. Lineaments were analyzed in relation to detect six specific major faults.
As the results, 3×3 operator of omnidirectional high frequency component enhancement (om3) images scored the maximum matched ratio for the major faults detection. The second best scores were the 3×3 operator of bidirectional image (ty3). Different filter sizes of mask operations show that the bigger size operators were not superior properly. Monodirectional filter images (tt3, tt5, yk3, yk5) were scored the lower matched ratio. Those results suggest that omnidirectional and bidirectional images are quite adequate to utilize for the fault detection. 3×3 mask operation is enough to enhance the images. Median filters are not fit to extract the lineaments.

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Although it will bring more to use both channel data of NOAA-APT as multi-spectral data in many fields of its applications, NOAA-APT cannot be treated as ordinary two channel multi-spectral band data. That is, the CH.A and the CH.B data of NOAA-APT cannot be laid on top of each others, because each of two channels data streams of NOAA-APT are created from consecutive AVHRR channel data.
A complex of two channels of NOAA-APT becomes a line interlacing, and shows usually a type of alternating line texture. Fog area shows especially evident line texture.
The author inspected seventy-three scenes which were received for three months from May 1994 till July 1994 by his receiving system. Sixty-three meso-scale fog area data are prepared for investigation out of forty-five scenes.
In order to characterize fog area using textural features, he has obtained co-occurrence probabilities, and made a survey of its distribution patterns.
As results, co-occurrence probabilities of cloud-free sea and fog area are clearly distributed separately. In cloud-free sea, because of small fluctuations in albedo which derived from CH.A and in Tm, which derived from CH.B, the distribution pattern shows a circle. In the fog area, fluctuations in albedo are large, the distribution pattern shows ellipse in albedo direction.
Next, in order to identify these co-occurrence probability distribution patterns, fifteen textural features included textural features proposed by Haralick et. at., are calculated.
As results, concerning textural features based on co-occurrence probabilities, ASM discriminates fog and cloud-free sea area at 89.5%, and ENTROPY at 84.2%, respectively.
Concerning textural features based on sum and difference co-occurrence probabilities, SUM AVERAGE discriminates fog and cloud-free sea area at 96.7%, DIFFERENCE AVERAGE at 93.0%, SUM ENTROPY at 91.2%, and DIFFERENCE ENTROPY at 91.2% respectively. CONTRAST textural feature shows time-variant

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The changes in spectral reflectance of plant leaves due to overlapping, leaf thickness, content of chlorophyll and content of water in leaf were investigated using spectrophotometer with integrating sphere. As experimental plants, we selected soybean (c.v. Fukuyutaka), sweet potato (c.v. Benikomachi) and mulberry (c.v. Tokiyutaka), which were main upland cultivar in Japan.
1) Spectral reflectance of leaf surface in near infrared range increased in ASLW (accumulated of specific leaf weight, g/cm²). In visible range, even if ASLW increased, spectral reflectance of leaf surface not increased.
2) In near infrared range, spectral reflectance of leaf surface linearly increased with increasing SLW (specific leaf weight, g/cm²) in the range of 0-0.05 g/cm², which showed leaf thickness. For soybean leaves, the equation was "Reflectance in near infrared range (800-1100 nm, %)=2010× SLW+47.2", where correlation coefficient (r) was 0.905. The correlation coefficient value was 0.514 for sweet potato and 0.806 for mulberry respectively.
3) Spectral reflectance of leaf surface from visible range to near infrared range increased with decreasing the leaf water content.

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[in Japanese]

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A specialty conference entitled "Land Satellite Information in the Next Decade" and its related exhibitions were held in Virginia, USA, in the period of September 25 to 28, 1995, by the American Society for Photogrammetry and Remote Sensing. This report was summarized by the members of the Remote Sensing Society of Japan who attended the meeting, as a reference material casting a prospect of Land Observation Satellite in the Next Decade. The description is a result after their discussion about their individual views obtained in the conference and the exhibitions.

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