Camera calibration without control points and automated orientation are being received attention for the operatinalization of digital photogrammety. Ideally, real-time camera calibration could be performed by using GPS and optical gyro. Such these equipments, however, are not widely diffuse due to the price aspect. Then, it is thinkable following two ways as a calibration method that is not depend on these equipments. One is a reducing control points by utilizing information such as distances which are included on the image. Another is a utilizing special equipment such as video theodolite. This paper presents the above two calibration methods for real-time photogrammetry.
A new elevation labeling method is proposed which can be applied to contour images including broken lines and inconsistencies caused by loss of contour lines and/or existence of irrelavant lines. Because conventional elevation labeling methods need ideal contours as an input data, broken lines and inconsistencies must be eliminated from the target contour image before elevation labeling. This elimination process (editing) has been done by human operator conventionally. The time-consuming human operation is a large problem in DEM generation from topographical maps. The proposed method has been developed In order to remove the above human operation. In the proposed method, a probablistic relaxation approach is used. That is, elevation probabilities are assigned to each contour, and then the probabilities are propagated to neighbor contours so as to decrease local conflicts.As a result, consistent labeling can be achieved even if the target contour image may include broken lines and some inconsistencies.
Currency of GIS databases, especially base map data, is strongly required in many GIS applications. It is expected that local government can keep base map data current very efficiently by using administrative information (building permit, notification of house demolition etc.) which is collected through daily routine. A unige contribution of this study is a comparative evalution of the efferctiveness of the administrative information in keeping base map data current on the quantitative basis using actual data. The authors use an expected variance of the number of buildings as a measure for evaluating the completeness of base map data. Actual percentage of building emergence and demolition covered by the daily administrative information (building permit, notification of demolition and ground survey for fixed property taxation) are surveyed from 1988 to 1991 in a study area of a local city with 500, 000 population. The survey shows 4-6% of the emergence and demolition were not captured. It is concluded that daily administrative information can not be a single data source in keeping the currency (completeness) of building data over long years. The appropriate combination of aerial survey and administrative data usage is suggested. Through a comparision of update methods combining administrative data and aerial survey data with a conventional aerial survey method in terms of the completeness of building data and total cost of update, it is demonstrated that the combining method is more advantageous in case higher priority is attached to currency of building data.
This paper aims to extract land surface temperature change in Tokyo and to analyze relation ship between land surface temperature change and land cover change. Land surface temperature patterns were derived from LANDSAT/TM Band6 data acquired at night in the summer of 1984 and 1994.Land cover patterns were obtained by the classification of TM data of corresponding periods. The higher-temperature zone had expanded from the center part of Tokyo to the suburbs in the west which had been urbanized in ten years. Land surface temperature change in the areas urbanized before 1984 was also investigated.In those areas, temperature difference between the city center and the surrounding regions reduced in ten years and it was proved that the reduction rate correlated with the urbanization rate. These results indicate that land surface temperature in the suburbs has been getting higher and closer to that of the city center in Tokyo due to urbanization.