The new method developed in this study was the use of nighttime AVHRR thermal data as an additional channel in classifying land cover types with respect to improve classification accuracy. The NDVI, ordinary brightness temperatures and land surface temperature, were examined using two-classification algorithms namely Maximum Likelihood and Decision Tree. Various band inputs were comparatively assessed for the classification accuracy. The results of classification in both cool and hot seasons showed that overall accuracy obtained by using combination of day and nighttime data was better than that obtained by using only daytime data. Using a combination of three bands including NDVI, daytime LST, and nighttime LST gave the best accuracy. Using three bands and only daytime data yielded a lower accuracy compared to when using only two bands, but with day and nighttime data. Although an overall accuracy of using only daytime and using both day and nighttime data was not remarkably different, the accuracies when adding a nighttime data were notably increased such as in a case of forest and built up classes. The nighttime data can well classify (1) forest from densely grown crops, (2) deciduous forest in hot season from sparsely growing crops and harvested agricultures, and (3) built up from harvested land. The results also indicated that the proposed approach using nighttime data was effective as a new classification method in vegetation environment associated with landscape. In addition, this study suggested an integrated approach involving day and nighttime data to monitor urbanization and heat island.
The cubic Hermite function was used as an interpolation method to generate the Digital Map 50m Grid (Elevation) by the Geographical Survey Institute of Japan. A Few studies have been reported concerning the reliability of cubic Hermite function for slope interpolation. However, these studies were mostly based on empirical observations without discussions about the cubic Hermite function's mathematical properties. In this paper, we investigate the applicability of the cubic Hermite function for slope interpolation using the mathematical relations between the trajectories of the cubic Hermite function and its tangent values at the both ends of the interpolation interval. The result shows that a proper slope interpolation can be achieved if and if only the trajectories' values are up to three times of the tangent's value.
Recently as the interest to the earth environment increases, research on a digital library system is getting much more popular.IIS, University of Tokyo, has been receiving AVHRR data at Tokyo since1984and AIT at Bangkok in Thailand since1997.Quicklook service for all the data are available on data strage system.However, raw data can not be freely downloaded and they have to be processed after download.In this study, we develop an AVHRR data processing system on WWW using PaNDA, which is a free software Package for NOAA Data Analysis.Using this system enables us to process AVHRR data on WWW with a few input parameters and download the processed data by FTP access. An easy to use interface is expected to promote the use of AVHRR data.