To verify the reliability of the algorithm for speculating physical variable from 1km satellite data, it is necessary to use the ground observational data to calculate physical value in a wide survey unit (1km × 1km) . Since it is difficult to conduct the ground observation within whole wide survey unit in short time, the minimal survey area which can represent a wide survey unit has to be determined. The research is armed to find the minimal representing area of a wide survey unit through the car survey and radio-controlled helicopter survey. Flat and homogeneous grassy plain in Mongolia is chosen as survey land. In case of car survey, 100 observational points are measured. VCR (Vegetation Coverage Ratio) values are calculated from spectrum information and used to compute the moving-averages of VCR. With the increasing of point number, the standard variation of moving-averages becomes smaller and smaller. When the variation approximately disappears after N points, the moving-average of VCR is considered as the observational value which can represent the value in wide survey unit. The total area size of N points at this time will be the minimal representing area of the wide survey unit. Moreover, the result from the car survey may be obtained occasionally from ground surface in same situation. To confirm the result, additional observational data are taken from higher sky using radio-controlled helicopter. Each observational point has about minimal representation area. The standard variation of moving-averages in this case is very small. So it can be said that the method used in the research is a good way to calculate the minimal representing area of a wide survey unit.
We have developed an underwater survey system using a scanning Laser sensor and a GPS (Global Positioning System) sensor instrment that is capable of providing high resolution data in low -visibility water. A laser is used as a light source which highly directional pulsed beams with high intensity. Topography is surveyed by detecting the propagation time of the pulsed laser beams which are reflected at the bottom of the sea. The laser system is installed in a ship and the beams are introduced to a ROV (Remotely-Operated-Vehicle) through an optical fiber. The extremely high propagation velocity of the beam in the water compared with that of an ultrasonic beam and the scanning survey system enable us to measure a large area within a short time.
Principal component analysis (PCA) is a multivariate statistical technique to summarize most of the variation in a observed multivariate system in fewer variables. It has been expected to be an useful technique to visualize the multiband remote sensing data. It is because the RGB color composite image using the summarized three principal components is expected to reflect as much information as possible of the original multivariate remote sensing data. It is known, however, that the actual color composite image employing PCA is not necessarily understandable one because the principal components are not distinctly correspondent to the electromagnetic wavelength, i. e. color, and consequently the relationship between the represented color and land cover becomes vague. This paper proposes a new type of the color composite technique by integrating PCA and the Normal Varimax Rotation (NVR) . The NVR is employed to make more distinct the relationship between each principal component and the electromagnetic wavelength by rotating the three dimensional space constituted by the first to third principal components. Since the NVR gives the orthogonal rotation, the three components after rotation represent the whole information of the original three principal components. This paper also presents the practical comparisons among the color composite images which are constructed by the conventional false color composite, the ordinary PCA, and the proposed NVR integrated PCA technique.
ADEOS/OCTS is an optical sensor with a low resolution and a frequent observation period for mainly observing ocean color and temperature. The highly precise geometric correction is necessary for some applications such as multi-temporal analysis, generation of floud free composite images, etc., where the accuracy of less than one pixel is preferable. But the accuracy by the system correction is not sufficient to those requirements. The authors have developed the system for precise geometric correction of NOAA/AVHRR imagery. The system utilizes GCPs and is adaptable for any number of GCPs. The system has been modified for OCTS imagery. In this paper, the differencies of OCTS from other sensors like AVHRR are pointed out at first and the modifications for the geometric correction of OCTS imagery are described.
The ski jump is scored by judges based on flight distance, style and performance. Generally, the flight distance has to be measured by many judges (distance measurers and recorder) according the FIS (Federation Internationale de Ski) rule. From the view point of real-time automated distance measurement in ski jump and effective utilization of a motorized video theodolite, a simulated ski jump was performed in a room by using a motorized video theodolite and an automated distance measurement method was investigated in this paper.
The authors attempted to detect crustal deformation by interferometric ERS-1/SAR data pairs. The Omaezaki-area which is located on the subduction zone was used as the test site. Three interferograms were generated from three sets of data pairs. Fairly good interferograms were obtained in both flat agricultural and urban districts; however, they were noisy in forest site due to large decorrelation. The changing patterns of phase difference in these interferograms indicated reasonable correspondence with tendency of subsidence of Omaezaki. Relative values of deformation between three data pairs had significant correspondence. Although, the interferograms may also indicate other factors that affected SAR signals during their transmission. The result of this study suggests the applicability of C-band SAR for detecting crustal deformation in Japanese test sites.