• Journal of Korean Society for Geospatial Information Science
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• v.2 no.2 s.4
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• pp.131-142
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• 1994

Generally, there are two methods which generates the base map of Geo-Spatial Information System(GSIS). one is the digitizing of existing map, and the other is the analytical plotting method editing data acquired by sensors using computers. But the analytical plotting method and method of the digitizing of existing map is technically complex and has the disadvantages in the costs and time. The subject region of study(the Kwangyang province), was photographed by aircraft, and photographing scale was 1/6,000. Then this area was divided into two specific regions, the residential area, and the agricultural area. In this study, we developed the algorithm that generated base map of database in GSIS from the aerial photo. This algorithm is as followed. First, the digital aerial photos were generated using these aerial photos. Second, these digital aerial photos were enhanced by implementing the histogram equalization. Third, the objects of the enhanced images were extracted by implementing thresholding and edged detection techiques of image segmentation. Finally, these images could be used to updated the base map of database in GSIS. The result obtained from this study showed that method used by this study were more efficient than existing method in costs and time.

• Journal of the Korean Association of Geographic Information Studies
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• v.17 no.4
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• pp.40-51
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• 2014

This study aims to investigate urban inundation considering building footprints based on dual-drainage scheme. For this purpose, LiDAR data is cultivated to generate two original data set in terms of DEM with $1{\times}1$ meter and building layer of the study drainage area in Seoul and then the building layer is overlapped as vector polygon with the mesh data with the same size as DEM. Then, terrain data for modeling were re-sampled to reduce resolution as $10{\times}10$ meters. As results, the simulated depth without considering building footprints has a tendency to underestimate the inundation depth compared to observed data analized by CCTV imagery. Otherwise, the simulation result considering building footprints revealed definitely higher fitness. The difference of inundation depth came from the variation of inundation volume which was relevant to inundation extent. If the building footprints are enlarged, the possible inundation depth is increased, which results in being inundation depth higher because hydrological conditions such as rainfall depth are conservational. Otherwise, according to comparison of inundation extents, there were no significant difference but the case of considering building footprint was revealed slightly higher fitness. Thus, it is concluded that the considering building footprint for inundation analysis of urban watershed should be required to improve simulation accuracy synthetically.

• Journal of the Korean Association of Geographic Information Studies
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• v.16 no.3
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• pp.115-125
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• 2013

The systematic management of river is difficult due to various environmental factors such as season and terrain deformation. Especially, river terrain are rapidly changing by natural and anthropogenic factors such as torrential rain during the summer and river development projects. Thus in this conditions, building the advanced river management system is an essential condition to support the ongoing management of survey data and to acquire data regularly through river terrain survey in order to maintain an active river. The need to build an efficient system have been increased through the enhancement and advancement of River Management Geographic Information Systems(RIMGIS). In this study, database design system and Riverbed Change Data Management Program was developed for systematic management of new river terrain survey data and the efficient use of river data dynamic changes. The key features are construction of river survey data, cross and longitudinal section monitoring and analysis of riverbed change data. Maintenance tasks which can be utilized in river-based architecture was constructed. The expected results are to be able to manage river systematically, and utilization of river topographic survey data efficiently for river maintenance work.

• Defense and Technology
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• no.6 s.172
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• pp.38-43
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• 1993

남아공의 무기체계는 대부분 해외기술도입이나 직구매에 의한 것들이 아니라 어려운 여건 속에서 자력갱생하여 얻어진 기술을 바탕으로 개발된 장비입니다. 이런 무기체계는 국경전쟁을 통해 성능이 입증되거나, 전장운용을 통해 성능이 개량된 것들로 남아공의 지형과 여건에 맞는 독자적인 모델을 갖추고 있습니다

• Journal of Korean Society for Geospatial Information Science
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• v.8 no.1 s.15
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• pp.111-120
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• 2000

A cadastral map that is base map on Land Information System is divided by two categories, graphical and digital cadastre. And digital cadastre can be displayed with location coordinates of nodes that depict parcel boundary on digital cadastral records. The transformation of digital cadastral records means that imported text data of node coordinate would be transformed into system data. This study was implemented to search reasons of errors resulted from transformation of graphic data and then to analyze the accuracy in terms of Position and area. For this, checking of software used in Geo-Spatial Information System was implemented at first and it was found that the accuracy is up by using double precision in coordinate transformation. On the position accuracy the errors at nodes was erased during making topology and the errors did not effect other nodes. On the area may the area errors because of being in error limit of allowable area had no problems in using of system.

• Journal of Aerospace System Engineering
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• v.16 no.6
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• pp.1-7
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• 2022

A simulated radar terrain scan data generation method is employed for terrain following. This method scans the discrete terrain by sequentially radiating beams from the radar to the desired scan area with the same azimuth but varying elevation angles. The terrain data collected from the beam is integrated to generate the simulated radar terrain scan data, which comprises radar-detected points. However, these points can be located far from the beam centerline when the radar is far from them due to beam divergence. This paper proposes a geometry-based terrain scan data generation method for analysing simulated radar terrain scan data. The method involves detecting geometric points along the beam centerline, which forms the geometry-based terrain scan data. The analysis of the simulated radar terrain scan data utilising this method confirms that the beam width effects are accounted for in the results.

• Journal of Korean Society for Geospatial Information Science
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• v.18 no.2
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• pp.107-112
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• 2010

Wind power generation is the natural source energy without pollution, and the highest economic efficiency among renewable energies. Amid the recent development of small wind power generation, wind power generation facilities can be installed in the super high-rise buildings or complexes. It is necessary to conduct analyses on appropriate locations in a bid to promote efficient power generation in those locations. In this study, relative weight of the elements required for the wind power generation were estimated by using the Analytic Hierarchy Process in Busan City, and the characteristics of wind velocity and wind direction in Busan City were expressed. As a result, 'Dadae 1-dong, Cheolma-myeon, Noksan-dong' was selected as the candidate region inside Gangseo-gu, Gijang-gun, Saha-gu by using the geo-spatial information system.

• Journal of the Korean Geographical Society
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• v.39 no.4
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• pp.514-527
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• 2004

We investigated the distribution and geomorphic development of alluvial fans at Cheongdo- and Hweyang-eup(town) in the Cheongdo Basin, Gyeongsangbuk-do(Province) of Korea. The alluvial fans of study area are formed confluently to the E-W direction at the northern slope of the Mt. Namsan(840 m). They are classified into Higher surface, Middle surface, and Lower surface according to a relative height to a river bed. And the older alluvial fan is, the deeper gravel in the stream deposits is weathered. The magnitude of each surface composing of confluent fans is related to that of the drainage basin. So called fan-basin system of magnitude on the study area is on the positive(+) relation in the study area. The large fans over 1km in radius are found on the basin of andesite rock which is resistant to the weathering and erosion. Moreover there is no tectonic movement in the basin. It means the most important element influenced on the fan formation is not tectonic movement, but the Quaternary climatic change, which is the periglacial climate alternating glacial and interglacial stages during the Quaternary. Therefore alluvial fans would distribute in Korea overall influenced by the Quaternary climatic change.

• Journal of The Geomorphological Association of Korea
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• v.19 no.4
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• pp.139-155
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• 2012

Most of previous landform classification methods using DEM compares the values between the center of the cell and the surrounding cells, which in turn, greatly depends on analysis scale. To overcome the problem of scale-dependency, a new classification scheme is developed, which is called "Geomorphons". Unlike the traditional approaches using DEM, Geomorphons is the way which compares the level with other cells against the criteria cell. As a pilot study, we classify the landforms of Pyeongchang-Gun in Korea. Then, we compare the result with the other methods such as Topographic Position Index. Through the systematic analysis, we obtain the following findings. First, Geomorphons can reduce the time for the classification of landforms because of using unsupervised classification. Second, Geomorphons is little dependent on change in the scale, which can provide a pilot tool for reconnaissance study for covering large area.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.364-365
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• 2003

모델에 입력되는 지형자료의 형태는 좌표별 고도가 체계적으로 정리된 DEM(Digital Elevation Model)형태를 사용할 수 있으며, 과거에는 이러한 지형자료를 얻기 위해 대상지역의 지형도 중 등고선을 대상으로 좌표별 고도수치를 정리하여 구축하거나, 섬세한 지형자료를 구축하고자 할 경우 각 고도별 등고선자료를 scan한 후에 각 등고선별 고도자료의 위상관계를 설정해 주는 작업을 진행하였으나, 두 방법 모두 상당량의 수정작업과 반복작업이 요구되는 단점을 갖고 있었다. 그러나 국립지리원 주도로 1998년 9월부터 시작된 NGIS(National Geogralhic Information Sydtem)사업에 의해 구축된 수치지도를 이용하여 등고선별 고도자료를 추출하고, 이를 가공하여 모델의 입력자료로 활용하는 방법이 최근에 소개되고 있으며, 지형자료의 구축에 소요되는 시간 및 정확한 자료를 구축할 수 있다. (중략)