RTK is one of the GPS positioning methods which enable real time positioning with millimeter level accuracy and is applied in surveying, machine control and so on. The experiments on RTK positioning accuracy with GPS only and GPS plus GLONASS were executed to investigate the relationship between DOP and positioning accuracy. Positioning accuracy was analyzed with standard deviation and RMS according to DOP value. As a result, it was shown that the standard deviation is related to DOP values and that RMS depends on DOP values and absolute position error.

Quasi-Zenith Satellite System is a satellite positioning system being developed by Japan. The improvement of opportunity for high accuracy positioning by using GPS together with Quasi-Zenith Satellite System is expected. In this research, the authors have developed the RTK positioning simulation method to estimate the effect of Quasi-Zenith Satellite System. As the simulation result, it was shown that Quasi-Zenith Satellite System improves the opportunity for RTK precise positioning drastically.

Disaster risk information, such as hazard maps, helps at-risk stakeholders understand the risks and take action to reduce them. The purpose of our study is to help people better prepared for disasters by providing them with a way to access and utilize specific disaster risk information, no matter where they are, using mobile phones equipped with GPS (Global Positioning System) and other position acquisition functions. The method we have adopted quickly displays risk information on the small screen of a mobile phone by showing the relative difference between the risk at the current location and that at the user's home. We confirmed the validity of the system through demonstration experiment.

Method of the inspection on bridge deterioration is, in general, that the inspecting person works on the operation basket attached at the end of the arm of the bridge inspection vehicle. However this method requires large-scale equipment and takes considerable time and manpower. This research was to develop a device to be able to perform the inspection on bridge deterioration easily. The device developed in this research is that a stereo video camera which can be controlled in any manner is mounted at the end of a 5 m long telescopic pole held by men's hands. This device has features that the condition of deterioration at a location where a person cannot approach, can be investigated easily and can be seen stereoscopically, and that the condition of deterioration can be measured quantitatively. This device was used for the inspection on bridge deterioration for the Metropolitan Expressway and its effectiveness was confirmed.

Inspections of linear structures have been carried out by close visual inspections, but they spend a lot of time. As an alternative technique for these, a method using video cameras has been reported. However, this technique causes image quality degradation and it cannot synchronize each cameras, and takes time for post-processing. In contrast, industrial cameras have higher precision and frame rates, and can be connected directly to PCs. However, to apply these cameras to inspections, it is necessary to solve their problems in photographing conditions. This time, the authors revealed the characteristics of the industrial cameras through laboratory experiments to solve these problems, and developed an “on-board image measurement system for actual running”. We verified the system on monorail track beams and at road tunnels, and confirmed that it can acquire high-quality images, and report the results in the post-processing in about a half period of time.

Recently several systems have been proposed as the mobile mapping system. However it is thought that the inspection of measurement accuracy is not sufficient. In this research, the experiments on the measurement of road associated facilities were executed by LANDMark system which is one of the mobile mapping system varying the running speed and the range to the object. As the results, it was proved that the system has the capability to measure the road associated facilities within 4m from the vehicle at the speed of 40km/h.

The walking direction image sequences in Oze national park are taken by camcorder, and analysis of sequential landscape is performed by theory of fractal in this paper. Moreover, positioning by GPS also performed during the walking, and distance from start point and altitude are acquired. As a result, 2 kinds of fractal analysis are performed by the image sequences, and complexity of the landscape for certain object and overall can be expressed respectively. Therefore, quantitative analysis for sequential landscape in Oze national park was realized. On the other hand, position for the each scene of the landscape can be obtained by GPS, the landscape was analyzed by relationship distance and altitude. Consequently, it can be seen that the supply of the objective information for the nature landscape by visitors will be realized.

Large scale maps such as drawings attached to ledger have been utilized for road management. Recently, such kinds of drawings are being digitized to make geographic information. Since sequential road drawing pieces are constructed individually, the drawings have to be connected and aligned. Alignment of each drawing by using many control points are time and cost consuming. Efficient method for sequential multiple drawings alignment and connection will contribute to GIS data development. This study proposes a possible alignment and connection method with small control points. Drawing pieces are connected at match lines, and then errors are adjusted according to a linear regression model. Generalized least squares method is applied to error adjustment, because each drawing has different accuracy (heteroscedasticity). Through the application to drawings of maintenance and repair construction, the significance of the method is confirmed.

These years in Japan, the demand for three-dimensional (3D) urban model is growing in various applications, such as preparedness to fire spread caused by earthquakes. Airborne LiDAR (Light Detection and Ranging) has been reported to be potential to effectively generate 3D urban model because it measures point clouds containing 3D coordinate which may be processed into the 3D model. As a preprocessing of the 3D modeling, point clouds are filtered to separate ground points from the non-ground points. However, it was found that the filtering of the point clouds in the densely urban areas is difficult because less ground data are observed than the traditional urban areas. Therefore, in the present paper, we propose an algorithm of the filtering which can be applicable for the densely urban areas. The results demonstrate that the algorithm can generate accurate and stable DTM (Digital Terrain Model).

Recently, the documentation and visualization of various cultural heritages have been receiving attention, and small Buddha such as less than 10 cm tall which was stored in the womb of Buddha is also included in cultural heritages. The authors have been concentraiting on digital very close range photogrammetry for these small objects using macro lens, and it was concluded that macro lens is suitable lens for the documentation of small objects.

In order to evaluate 3D modeling in digital very close range photogrammetry, triplet images for 17 mm diameter one dime were taken using macro lens. This paper presents ability of macro lens for 3D modelling in digital very close range photogrammetry.

The consumer digital stereo camera; FinePix REAL 3D W1 was released by FUJIFILM Cooperation in August, 2009. Since the REAL 3D W1 camera was designed to take a pair of stereo images for stereo viewing, the baseline length of 77 mm of the camera is unsuitable for accurate stereo measurement. The aim of our study is to evaluate the accuracy of measurement using a pair of stereo images acquired by the REAL 3D W1 camera without any controls. We evaluated the accuracy of 3D measurement with three parameter sets. The first parameter set was extracted from the obtained image file, the second one was obtained by camera calibration, and the third one was estimated by using a pair of stereo images depicting a scale. As a result, since an image file has no information about digital zooming, the obtained image file cannot provide a reasonable measurement result without any additional information. Meanwhile, the camera calibration would provide measurement results of 10% error at the most. Therefore, the REAL 3D W1 camera would be very useful tool for easy 3D measurement.

The authors have been concentrating on developing a convenient 3D measurement system using consumer-grade digital cameras, and have concluded that such a system can be useful for various close-range applications. However, there are still some issues to be resolved before high-accuracy photogrammetry is possible using consumer-grade equipment. One such issue is the acquisition of accurate scale factors, which are necessary to transform pixel coordinates into image coordinates. Previously, scale factors were typically computed using the numbers of horizontal and vertical pixels in the camera display and the sensor sizes that were included in the manufacturers' specifications. Recently, however, it has become impossible to obtain sensor sizes for consumer-grade digital cameras, even from manufacturers' specifications, and thus scale factors must be estimated based on the sensor type (e.g., 1/2 inch CCD sensor). Therefore, in order to achieve high-accuracy photogrammetry using consumer-grade digital cameras, we investigated accuracy aspects of scale factor behavior using 4 consumer-grade digital cameras and 2 single-lens reflex cameras, and it was concluded that scale factor should be considered as unknown parameter to perform high-accuracy photogrammetry using consumer-grade digital cameras.

Perception for a foresight of slope failure occurrence is currently dependent on human sense. This investigation examines a system which enables to inform rescue team at the slope failure site of an evacuation alert as soon as possible by perceiving foresight of the secondary disasters of the slope failure using sensors. The system has a function that transmits e-mail, etc to the rescue headquarter and rescue team members immediately after being detected the movement of the slope failure by the inclination measuring device installed at the slope failure site. Effectiveness of the system was demonstrated in the laboratory through the fundamental experiment.

This development developed the material management system using CAD data to aim at efficiency improvement and effective use of the business that used analog data. The feature of this development can confirm the whereabouts confirmation, the geographical point, the range, and content information on analog data converted into digital data by using CAD data. In the main discourse, it reports on the outline and the process, the verification, and the verification outcome of the system.

Recently, the demands for the three-dimensional (3D) models of buildings in the cultural heritage and the urban area have risen. Though a lot of examples of 3D modeling of cultural heritage have been reported, available 3D models of urban area are quite limited because the measurement condition in the urban area is poor. The author focused on digital photogrammetry for the urban modeling because it can achieve high accuracy, have high portability, and the cost of the equipments is low. In this study, the author conducted close range digital photogrammetry in the area near Houkanji-temple in Kyoto and the Old Quarter of Hanoi, and then, 3D model of buildings were produced. As a result, it was found that the accuracy is acceptable. In terms of the accuracy and the efficiency, the author concludes that digital photogrammetry is an effective approach to urban modeling.

Toward the realization of the society in which geospatial information is utilized in advanced way, satellite positioning and GIS technologies are now applied in various services provided by public as well as private sectors. Establishing efficient methods for collecting geospatial information is a basis for such society. Authors have been developing some field survey tools by combining digital devices including GPS and digital cameras, and applying them to actual projects. This paper reports a PDA-based field information management system using a GPS and a digital camera, as well as a mobile data collection system with a spherical camera. The former system can navigate surveyors in study areas and record survey routes using GPS, and the portable GIS on a PDA can be used to collect attribute information and field snapshots taken with a digital camera. The latter system can record continuous panoramic video footage along survey routes, and geographic information can be extracted from recorded images using a PC system after surveyors return to their office. Authors optimize the efficiency of field surveys by utilizing appropriate digital tools such as mentioned above.