A new bilateral fisheries agreement was formed between Japan and South Korea in 1999. Since February 22, 1999, the two countries have set the exclusive fishing zone and are jointly controlling a provisional fishing zone encompass the Takeshima (Tok-do in Korea) Island. The borders of the zone are 35 nautical miles from the shores of both countries, with the eastern border at 135 degrees 30 minutes east longitude. Squid anglers and surrounding-net fishers in this area use powerful lights when fishing at night. The authors have examined the night time DMSP/OLS images taken before and after the fishing zone initiation. The light-fishing fleet distribution in the images strongly suggests that the fishing agreement is effectively controlling the location of fishing fleets around this area.
Minnaert correction method is one of the most appropriate models that correct topographic effects on remotely sensed data. However, the variations of the Minnaert constants have not been examined for any forest types. The purpose of this research was to investigate the extent of the variation of the Minnaert constant in three different forest types. Three forest types were selected for the analysis ; broad-leaved natural forest, coniferous plantations, and bamboo forest. 7 scenes of SPOT/HRV data observed in 1997 were selected and orthorectified with digital elevation models and digital topographic maps. The Minnaert constants were obtained through a regression analysis between solar incidence angles and the original satellite data. The results showed bands 1 and 2 indicated the seasonal variation of Minnaert constant, which had the peak in summer. In those bands, there were negative correlations between the solar zenith angles and the Minnaert constants. On the other hand, the band 3 indicated unclear variations in the Minnaert constants rather slight fluctuations. Then there was not significant correlation between the solar zenith angles and the Minnaert constants of the band 3. The results of this study suggested that visible band and near infrared one differ in the annual change pattern of the Minnaert constant.
Since the GMS-5 observes the earth very widely and frequently, its S-VISSR data are very useful not only for meteorology but also for sea surface and land surface temperature analysis, heat and water budget analysis and the various kinds of database generated from the S-VISSR data will contribute the understanding of earth environmental change. In order to process GMS-5 S-VISSR data immediately after reception and provide academic researchers the geometrically corrected data useful for the time series analysis, a high-speed and precise geometric correction method is described. For precise geometric correction, residual errors are acquired by matching the S-VISSR image pieces to their corresponding ground control point templates on image coordinate, and the affine coefficient is calculated using the errors. For fast computation, the output image of the map coordinate is divided into small blocks. Each latitude-longitude of four corners on a small window is converted to line-pixel in image coordinate by systematic geometric transformation and affine transformation is carried out toward the line-pixel for precise geometric correction. In the case of internal points excluding four corners in the small window, each correspondence of line-pixel and latitude-longitude is calculated by hi-linear interpolation using correspondences of the four corners for speeding up the geometric correction. As the result, the accuracy measured at low altitude points is about 0.5 pixels in average and within 2 pixels, and the processing time is about 6 minutes. The product is open for public use via the Internet.
A spatial feature extraction method based on Gabor descriptor is proposed. It is found that the restored image quality, in terms of root mean square error between the original and the restored images depends on the support length of the mother wavelet and is much better than that with Fourier descriptor which is existing method for spatial feature description.