To grasp the noise level near roads is very important to control the noise pollution caused by vehicular traffics. A prediction model of ambient noise level (L50) in the vicinity of roads was established. The model based on EPA model (E.A.G. Shaw and N. Olson, 1971), so the sounds propagation characteristic was considered as exp(-β )/r2, where r is the distance from a source to an observed point and β is an excess attenuation coefficient. Furthermore, an excess attenuation coefficient was so derived as to fit the results of leda's model (S. Ieda et al., 1983). In our model, the building coverage rate plays the most important role in sound propagation. The rate was estimated from five kinds of band data (excepting midle and thermal infrared bands) of Landsat TM data (September 6, 1984) in Osaka district. The principal component analysis method and multi-regression analysis were used here. The correlation coefficient betweeen estimated values of building coverage rate from Landsat TM data and ground truth data was 0.915. The model was applied to an actual area in Osaka prefecture, and somewhat good result was derived.
About 264 ha of forest area in the southern part of the Miyajima Island was burnt mosaicly in March, 1984. It was not easy to estimate the area damaged by fire. The availability of Landsat MSS data at the estimation of burnt area of both forest canopy and undergrowth was examined. The mesh data about the ratio (BR, %) of burnt area to the total one and ratio (R, %) of illuminance on the ground surface to vertical flat to sun radiation were estimated based on ground survey and geographical map, respectively. The relation between R and Landsat data showed that illuminance (digital number, DN) of Band-6, 7 was separated into three groups, i. e., forest (BR=0), middle damaged (20 ≤ BR<80) and heavy damaged (80 ≤ BR) areas (meshes), while there was little difference in the case of Band-4, 5. DN of Band-6, 7 in the forest and middle damaged areas increased in proportion to R. The fact meant that DN of Band-6, 7 was in need of the geographical correction based on the linear relation between them. There was closely negative linear relation between corrected DN (DN') of Band-6, 7 and BR. It suggested that BR could be derived from the DN'. The burnt area (meshes) was classified into five grades of burnt ratio based on the DN' of Band-7. The area of burnt both forest canopy and undergrowth was calculated at 165.0 ha and also that of burnt only undergrowth was estimated at 99.4 ha from the classification map. These estimated areas by Landsat MSS data were closely coincided with those obtained by the ground survey.
Flooded areas in the middle basin of Sakura river and Kokai river, Ibaraki Prefecture, caused by the heavy rain affected typhoon No. 8610, were classified by the supervised method using Landsat TM data taken on August 6, 1986. Outcome of the classification was directly plotted into the topographical map from the standpoint of practical use using the general-purpose plotter with 8 color-pens. In disaster survey it is always essential to compare the result with ready-made topographic map in some way. It was found that slight inclination of the ground surface could be interpreted from the plotted map of classified flooded areas. The plotted map was put to practical use and evaluated high against aerial photos by the local self-governing body.
Large amount of data in relation to the Izu-Oshima eruption in 1986 were obtained by satellites, by airplanes, and through the ground works. This article intends firstly to make an inventory of the data. This inventory will indicate the place of data which may become obscure in time. The data were generally divided into three categories, satellite derivation ones, aerial derivation ones, and the other source data. Satellite data are classified in accordance with the satellite types as GMS, NOAA, Landsat, and SPOT. Aerial data are arranged in accordance with the data acquisition organizations including ASDF, GSI, NHK, Asia Air Survey Co., Ltd, Kokusai Aerial Surveys Co., Ltd, Pasco Corporation, Aero Asahi Corporation, Nakanihon Aviation. The other data are chosen as the data useful for the survey and research of volcanic activities from the data obtained before the eruption for the other purposes. The data include SAR imagery, aerial geomagnetism data and aerial photographs obtained by GSI, NEDO, and NASDA. This article intends secondly to show some of the actual data, because that the data themselves inform us the substance of volcano. The authors attach the data acquisition circumstances and characteristics, and some comments relating to the volcanic phenomena. We hope that these description may help those who observe the data, and also that the inventory and presentation in this article may contribute to new discovery in volcanic science. The presentations are as follows; (1) SAR imagery with X band VV showing old craters and lineaments. (2) Landsat/TM data covering the Izu-Oshima island before and after the eruption. (3) Landsat/MSS IR color composite showing the high temperature at the central crater. (4) Aerial IR imagery at just before the big eruption. (5) Night stereo aerial photographs showing the periodical up-welling of lava at the central crater. (6) GMS-3/IR image showing the discharge of volcanic ash cloud to the atmosphere. (7) NOAA/AVHRR image showing high temperature positions and the discharge pattern of volcanic materials. (8) Aerial color photographs taken at the earliest time after the eruption. (9) Oblique aerial color photographs showing the rising volcanic gas. (10) Aerial IR color photograph distinguishing the lava flow and vegetation area. (11) Aerial color mosic showing the discoloring water area. Finally, geometrically corrected views of Izu-Oshima are shown with some description. Those are; (1) Perspective image of Izu-Oshima island with the surrounding sea bottom topograpy. (2) Aerial M2S image from an altitude of 2000m showing precise thermal condition.
The Technical Commitee of Data Processing of the Remote Sensing Society of Japan conducted the survey on the present state of the art of image processing and analysis techniques of remote sensing data using a personal computer, for the aid of practical use of a personal computer system for remote sensing data applications. The survey was continued from January to September in 1986, and, finally, this report was edited according to the result of the survey and the discussion by the editorial members of the commitee. The survey was conducted based on the papers presented at the Japanese Conference on Remote Sensing by the Remote Sensing Society of Japan, and the report summarized the present status and the future direction on theree major items, hardware system, software system and system applications.