• Journal of the Korean earth science society
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• v.25 no.8
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• pp.784-798
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• 2004

Microscale wind fields were simulated by MUKLIMO at the Naro Space Center, where complicated mountainous terrain and trees exist. In order to test the model's sensitivity with the effects of terrain and trees, experimental simulations were conducted under the various initial conditions. The experiments showed that the effects of trees were more significant on flat surfaces than on mountain cliffs. Based on the results, an actual 10 m level microscale wind field was simulated at the Naro Space Center, which has complicated mountainous terrain. Simulations of wind fields before and after the construction of the launching site were also conducted. It was found that MUKLIMO was of the mesoscale wind fields at the Naro Space Center.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.10 no.2
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• pp.31-36
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• 1992

Geo-Spatial Information Systems(GSIS) are being used in various urban municipalities as a tool in decision making. Efforts are being made to implement geo-spatial information system databases to systematically and effectively carry out planning, management and monitoring in various fields. This study is about the database establishment of geo-spatial information systems. The study was then applied to water supply facilities management, where the functions and data used in water management were identified through system analysis and the geo-spatial database was designed based on this analysis. Also four application programs were developed to support departments which used various maps and drawings.

• Water for future
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• v.14 no.3
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• pp.37-46
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• 1981

The purpose of this paper is to provide a method of estimating the magnitude and frequency of floods on five major streams in Korea such as the Han, the naktong, the Geum, the Seomjin and the Yeongsan. Derivation of the flood frequency formulae is based on the multiple correlation method. For each gaging station in the region, flood frequency curves are drawn by GumbelChow and Weibull plot. where 24 gaging stations are selected for this study. After the station flood-frequency cruves have been prepared, discharges are read at selected recurrence intervals. Each set of discharges is then correlated with basin parameters, using regression equation. The basin parameters that are considered include drainage area, length of main stream, shape facotr, mean basin slope and main channel slope.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.13 no.1
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• pp.41-47
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• 1995

In this study, we try to develope the radio control photographing system with 35 mm camera to obtain 3-dimension large scale geographic information more effectively, to automatize and computerize the basic design and practical design of road. By applying this system on getting data which is needed to design road, this study has an object to promote efficiency in possesion and management of geographic information. As result of this study, this system could obtain geographic information effectively on the object region, could get large scale geographic information which was suitable for expected accuracy by photographing in 400 m height and could ac-quire profile, crossection and earth-work volume quickly and exactly.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.17 no.4
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• pp.349-357
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• 1999

Hydrologic parameters vary spatially and require interpretation of maps which often vary in scale and accuracy. Data requirements can be extensive, and acquisition and manipulation of the data are time-consuming. The purpose of this study is to develop Hydrologic Terrain Factor Extract System (HTFES) using Geo-Spatial Information System(GSIS). The HTFES is a package of spatial data and menu-driven programs that allows user-interactive determination of hydrologic parameters. The program employs Arc/Info, a commercial Geo-Spatial Information System. Spatial analysis techniques were employed to define watershed outlets and to determine important hydrologic parameters. The system delineates drainage boundaries, flow paths, average watershed slope and etc. using relevant digital elevation data.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.17 no.4
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• pp.393-401
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• 1999

Non-point source pollution poses a serious threat to river. therefore non-point pollution model was developed. This non-point pollution model requires detailed spatial data for accurate predictions Geo-spatial Information System(GSIS) is well suited to those needs. The parameters for these models provided by the GSIS were slope, slope shape, field slope length and SCS run off curve number. Hence, this study presents an application of GSIS processing tools for AGNPS model developed by the ARS(Agricultural Research Service) in cooperation with the MPCA(Minnesota Pollution Control Agency) and has developed interface that construct the input data of ASCII type in the AGNPS model using GSIS.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.8 no.2
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• pp.1-8
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• 1990

A regular grid or a triangulated irregular network is generally used as the data structure of digital terrain models. A Regular grid is simple and easy to manipulate, but it can't describe well terrain surface features and requires vast volumes of data. In the meantime, a triangulated irregular network has complex data structure, but it can describe well terrain surface features and can achieve the accuracy suitable to its application with relatively little data. This paper aims at the construction of efficient digital terrain models by the improvment of a triangulated irregular network based on Delaunay triangulation. Regular and irregular data set are sampled from existing contour maps, and the efficiency and the accuracy of the two data structures are compared.

• Journal of KIISE:Databases
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• v.33 no.4
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• pp.384-395
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• 2006

Topographical images such as aerial and satellite images are usually similar with respect to colors and textures but not in shapes. Thus shape features of the images and the methods of extracting them become critical for effective image retrieval from topographical image databases. In this paper, we propose a shape feature extraction method for topographical image retrieval. The method extracts a set of attributes which can model the presence of holes and disconnected regions in images and is tolerant to pre-processing, more specifically segmentation, errors. Various experiments suggest that retrieval using attributes extracted using the proposed method performs better than using existing shape feature extraction methods.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.11
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• pp.1104-1111
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• 2009

In the low altitude, mission of the aircraft is restricted by a variety of threats such as anti-air missiles and terrain obstacles. Especially, aircraft have always a risk of ground collision near terrain. In this study, to effectively solve this problem, we developed the flight path generation algorithm that is considered the terrain avoidance. In this flight path generation algorithm, waypoints that should be passed by the UAV are selected first. The waypoints are located in the middle of the terrain obstacles. Then, physically meaningful waypoints sets are classified by Dijkstra algorithm. The optimal waypoint guidance law based on the optimal control theory is applied to produce trajectory candidates. And finally the minimum control energy trajectory is determined.

• Journal of The Geomorphological Association of Korea
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• v.20 no.1
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• pp.75-83
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• 2013

Human-induced modifications in coastal area may cause strong geomorphic responses by disturbing sediment supply, transport and deposition regimes. Morever, engineering structure have been built to stabilize coastal change, these effort impact on other morphologic change. In case of coastal area, there are lack of sediment yield data. This study focus on the tendency of long-term shoreline change, estimate method od sediment discharge which is a major factor of coastal change and adduced to way for considering design load influenced to coastal road.