• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2003.04a
• /
• pp.215-218
• /
• 2003

There are lots of ways to measure earth-volume, but recently Total Station and GPS are more frequently used. According to the advance of science, acquisition and processing of image by camera are also going to make great progress. So that, in this study, we search the efficiency for earth-volume calculation using digital photogrammetry.

• Journal of the Korean Geophysical Society
• /
• v.9 no.1
• /
• pp.7-19
• /
• 2006

Laser scanning is a new technology for obtaining Digital Surface Models(DSM) of the earth surface.It is a fast method for sampling the earth surface with high density and high point accuracy. This paper is for buildings extraction from LiDAR points data. The core part of building construction is based on a parameters filter for distinguishing between terrain and non-terrain laser points. The 3D geometrical properties of the building facades are obtained based on plane fitting using least-squares adjustment. The reconstruction part of the procedure is based on the adjacency among the roof facades. Primitive extraction and facade intersections are used for building reconstruction. For overcome the difficulty just reconstruct of laser points data used with digital camera images. Also, 3D buildings of city area reconstructed using digital map. Finally, In this paper show 3D building Modeling using digital map and LiDAR data.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2006.06b
• /
• pp.87-90
• /
• 2006

The Earth's spherical harmonic model of the main field and of the secular variation, of the geomagnetic field gives the intensity and geomagnetic structure at any location around the earth, assuming an undistorted, steady state field that no external sources or localized earth anamalies. To consider the practical use of a ship's digital compass in earth's magnetic field, Earth's spherical harmonic model is searched for the related practical methods and procedures as a basic study in this work.

• Journal of Satellite, Information and Communications
• /
• v.8 no.2
• /
• pp.88-93
• /
• 2013

The wideband chirp signal generator to enhance the resolution of synthetic aperture radar of obtaining the earth observation image is needed. This paper deals with designing, manufacturing and testing the wideband digital chirp signal generator having high resolution for LEO earth observation satellite. The wideband digital chirp signal generator is implemented with the memory-map based structure which is mostly applied in the satellite, and consists of the digital module to generate the digital chirp signal and the RF module to perform the quadrature modulation. The I/Q signals stored in the memory of the digital module are D/A converted and delivered to be quadrature modulated with the reference signal of 1275 MHz in the RF module. Furthermore, the test bench and GUI to validate the signal generator function are also developed. It is found that the requirement of 144 MHz bandwidth for the digital chirp signal generator is well met. Finally it is noteworthy that the distortion occurred in the chirp signal generator was compensated by the pre-distortion compensation.

• The Journal of the Korea Contents Association
• /
• v.13 no.3
• /
• pp.318-329
• /
• 2013

Spatial information has influenced government policy formation, business strategy implementation, and our everyday life enormously. Digital earth enterprises providing global spatial data services emerge as spatial data industry grows rapidly. So it is highly desirable to grasp recent trends in the industry and find critical success factors (CSFs) for the digital earth firms. The purpose of this study is to compare strategies of digital earth enterprises and find CSFs for them. In addition, strategy analysis framework elaborations, systematic analysis of spatial data industry and market segmentation based on value chain are also performed to trace and cope with the volatile industry environment. Derived CSFs are as follows. First, acquisition of differentiated high quality spatial data is needed. Second, customer oriented convergent contents should be developed. Third, advanced platform functionalities must be provided to consumers. Finally, construction of efficient and effective global value chain is desirable.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.7 no.2
• /
• pp.7-19
• /
• 1989

The developments in remote-sensing, digital mapping, and automation of land information system have provided the impetus for the increasing use of Digital Terrain Models in engineering planing and design. In this paper, an evaluation is made on tile method of accurate earth-volume determination in computerized road design using by Digital Terrain Models. The result of numerical test shows that the $BL_{in}$-1 Model is the most efficient model in Earth-volume determination of road design.

• Proceedings of the KSRS Conference
• /
• 2003.11a
• /
• pp.1058-1060
• /
• 2003

A ground control point (GCP) is a point on the surface of Earth where image coord inates and map coordinates can be identified. The GCP is useful for the geometric correction of systematic and unsystematic errors usually contained in a remotely sensed data. Especially in case of synthetic aperture radar (SAR) data, it has serious geometric distortions caused by inherent side looking geometry. In addition, SAR images are usually severely corrupted by speckle noises so that it is difficult to identify ground control points. We developed a ground point extraction algorithm that has an improved capability. An application of radargrammetry to Daejon area in Korea was studied to acquire the geometric information. For the ground control point extraction algorithm, an ERS SAR data with precise Delft orbit information and rough digital elevation model (DEM) were used. We analyze the accuracy of the results from our algorithm by using digital map and GPS survey data.

• Proceedings of KOSOMES biannual meeting
• /
• 2006.11a
• /
• pp.131-135
• /
• 2006

The objective of the project is to model and study the geomagnetic field structure and its secular variation in space and in time due to sources in the dynamic fluid outer core. the Earth's spherical harmonic model of the main field and of the secular variation gives the intensity and geomagnetic structure at any location around the Earth, assuming an undistorted, steady state field that no external sources or localized earth anomalies. To consider the practical use of a ship's digital compass in Earth's magnetic field, Earth's spherical harmonic model is searched for the related practical methods and procedures as a basic study in this work.

• Korean Journal of Remote Sensing
• /
• v.18 no.1
• /
• pp.25-33
• /
• 2002

In 1799, Korea has become a country that holds Earth observation satellite in orbit as they had succeeded in the launch of KOPMSAT-1, the first Korean Earth observation satellite for the practical purpose. For the wide application of the satellite imagery, various application techniques are required, and topographic mapping is essential technique for the application in various fields. Moreover, considering that the main mission of the KOMPSAT-1 is to provide the satellite imagery for the mapping of Korean peninsula, the topographic mapping using KOMPSAT-1 EOC imagery is very significant. In this paper, we showed the possibility of digital plotting using KOMPSAT-1 EOC stereo images to produce topographic map. For the purpose, we implemented experimental stereo plotting using digital photogrammetric workstation and analyzed the procedure. As a result of this paper, we showed that some elements consist in 1:25,000 scale map can be plotted from KOMPSAT-1 Stereo images.

• Proceedings of KOSOMES biannual meeting
• /
• 2006.11a
• /
• pp.137-141
• /
• 2006

To consider the practical use of a ship's Digital Compass in earth's magnetic field high accurate Deviation and 얘 nation are required to obtain ship's true bearing. Variation can be obtain with World Magnetic Model (WMM) using the Earth's spherical harmonic model of the main field and of the secular variation at any location around the earth. Deviation can be obtain with deviation analysis and synthesis method based on the Poisson equations. As results of deviation and variation corrections to the Digital Compass, high accurate true bearing is obtained. This experiments are carried out during in the navigation of training ship 'SAE-NU-RI'.