Degree of damages. by earthquake varies with the dynamical signature of the surface soil. Various counterplans have been taken against a probable earthquake in Tokyo, where it has passed over 60 years after the Kanto earthquake in 1923. To estimate the damages by earthquake and also to make an optimum counterplans against it, there needs to know the soil structure in the region and also to make clear the distribution. As for Tokyo 23 wards, the surface soil maps and meshed dangerous degree maps about liquidation have been compiled according to the results of boring surveys carried out so far. The authors approarch a production of such maps by means of remote sensing. This report discribes an examination about the method to classify the soils in the Tokyo area into two categories ; effeminate Alluvia and stable Kanto loam.
Among 64 Landsat MSS scenes of Kanto(Path: 115, Row:35) which EOC of NASDA has received, 3 scenes can be chosen as appropriate ones presenting the similar distribution pattern of surface soil to that seen in the conventional surface soil map of Tokyo 23 wards. Among these 3 scenes, one scene on May 21, 1979 which is considered to reveal the distribution of two types of soil in best is
investigated.
Comparing 4 MSS band images by each, the following becomes clear. Surface soil distribution pattern can not be recognized so clearly in the images of MSS 4, 5, and 6 bands. Whereas, a fairly clear discrimination of soils is seen in that of MSS 7.
Next, the border lines between high and low lands was delineated by observing the enlarged MSS 7 image. This newly described border lines are very similar to that on the conventional surface soil map. A reason of the discrimination of high and low lands in the MSS 7 image may be due to the difference of vegetation.
Finally, the means and standard deviations as of the depth of weak soil strata and the MSS 7 CCT counts in both lands were. obtained on the basis of actual boring data in the lower basin of Tama-gawa. The data distribution for both lands differs a little from each other. This indicates that there is a possibility to classify soil types into two categories using Landsat MSS data.

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The spectral reflectance and degree of polarization of plant leaves of different species (conifer, broad leaf tree and different surface roughness, etc.) are measured in a laboratory. It was found that reflectance characteristics of each plant leaf are influenced by the pigments contained in leaves, especially by chlorophyll in visible spectrum with the minimum values at blue and red bands (approximately 4 %) and the maximum value of 18% at green band. It was found that the degree of polarization depends on the surface condition of a leaf.
In case of smooth surface leaves, a general trend of the degree of polarization increases between 0.56, um and 0.68 km with a little variation. The numerical values of the degree of polarization are 0. 13 at 0.56 pm and 0.40 at 0.68 um for the smooth surface leaves (Pasania edulis Makino.). While in case of rough surface leaves the degree of polarization increases monotonously with the numerical values of 0.22 at 0.56 pm and 0.35 at 0.68, um respectively.
Both the reflectance and degree of polarization of leaves are influenced by leaf moisture content of leaves in the near IR spectrum due to the fact that water absorption band exsists in this spectrum and that its influence on the reflectance is larger than that on the degree of polarization. The reflectance of leaves in the near IR spectrum increases in proportion to decrease of moisture content of leaves. For a leaf dried to 50% of moisture content of a fresh leaf the increase reaches as large as 26% of the reflectance of fresh leaves, while in case of the degree of polarization it decreases by 1.7% of that of fresh leaves. The effect of superposition of leaves on both reflectance and polarization was also measured up to a stack of five leaves. In case of a stack of two leaves the reflectance decreases by approximately 1% throughout the spectrum ranging from 0.46 um to 0.68 pm however it increases as much as approximately 10% in near IR spectrum. For a stack of more than three leaves no further significant decreases is observed in visible spectrum while in near IR spectrum the further increases of reflectance is observed reaching by 14%, 15% and of 16% of that of the case of one leaf respectively. As to the relation between reflectance and degree of polarization, a negative correlation was observed.

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We have constructed a large scale laser radar system.
There are two types of systematic errors which occur in the measurement of wide area by using the system. Those are about measured signal intensity and the aiming error. The problem of the signal intensity was solved by using a gain switching circuit which changes the gain of the photomulttiplier and by adopting the dynamic range increasing methods. The aiming error. which is caused by the curvature of the earth and the refractive index of the air, are estimated numerically.
From the calculation of S/N, this system was proved to be working as had been designed.

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Based on Landsat MSS and RBV and other conventional data, total number of 1628 lineaments in Northern Korean Peninsula were extracted. Statistical analysis on the distribution of the extracted lineaments indicates the following characteristics. There are two prevailing direction in the orientation of the lineaments. i.e. one is from West-North-West to East-South-East while the other is from North-East to South-West directions which are considered due to the Shorin Metamorphosis in Triassic Period and Taiho Metamorphosis in Jurassic Period of Mesozonic Era. The most pronounced directions are 35°-215° followed by 285°-105° in azimuth angle. On the other hand the least prevailing direction is 315°-135°.The maximumun average length in 10 degrees class interval is, 22.6 km in the direction of 25°-205° while that of the minimum is 10.4 km in the direction of 335°-155°.
In case of 4 subdivided areas based on geologic characteristics, although the prevailing direction in general has a certain similarity to that of the whole area, the distribution of lineaments indicates a little difference in both prevailing direction, average lenght and density of the lineaments. The maximum and minimum densities of lineament distributions are found in the northern middle and the southern subareas with 16.6/10km2 and 10.3/103km2 respectively.

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A synthetic aperture radar (SAR) is one of the promising microwave sensors for earth observation. The National Space Devolopment Agency of Japan (NASDA) started the phase A study (preliminaly analysis) in FY1978, recognizing the importance of active microwave remote-sensing.
The research and development proceeded to phase B/C (definition/design) after the heated discussion on the Earth Resources Satellite-1 (ERS-1) at the Space Activities Comission in August 1980. Recently the technically critical components have been developed and the basic tests completed. At present, the final stage of the phase is going on. In this paper, the policy, the goals and the schedule of the research and development on SAR are described. The major test results of the following critical technologies are also introduced.
1. to keep the antenna pannels flat. in the space environment,
2. to obtain high power by solid-state amplifiers,
3. to get a large time-bandwidth-product (TBP) for pulse extention,
4. to achieve high frequency stability with crystal oscillator.

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Usually CCT (Computer Compatible Tape) is used as the secondary memory medium in the digital image data handling. Even though the computer systems are different from each other, the digital image data can be exchanged among them using CCT in the most cases. However most of micro-computer systems don't support CCT controller. Recently, as the usefullness of micro-computer systems in the image processing has increased, a new data handling method for micro-computer systems has become necessery.
Since this spring RESTEC has started a new distribution of Landsat MSS data by 8-inch floppy disk to the micro-computer users. 8-inch floppy disk is one of the most popular secondary memory medium for micro-computer system. This report describes about an overview of 8-inch floppy disk and how to handle "RESTEC Landsat floppy disk" using micro-computer systems.
The format of RESTEC Landsat floppy disk is as follows.
1. Disk-format
* Physical format
IBM Part 1766872
* Logical format
IBM (256-2D) format
2. Data format
BIL or BSQ
512pixels X 4001ines X 1byte X 4bands
Micro-computer system usually has its own disk logical format according to its own operating system. The authors propose two ways to handle the RESTEC Landsat floppy disk using micro-computer system. One is to use IBM format conversion program supported by the micro-computer makers. Another is to use the secter access command of BASIC and readout the data in a certain secter of the disk. The authors call the later method "Direct sector access method".

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