• Korean Journal of Remote Sensing
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• v.13 no.1
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• pp.57-73
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• 1997

This paper is related to the correction of radiometric distortions induced by topographic relief. RADARSAT SAR image data were obtained over the mountainous area near southern part of Seoul. Initially, the SAR data was geometrically corrected and registered to plane rectangular coordinates so that each pixel of the SAR image has known topographic parameters. The topographic parameters (slope and aspect) at each pixel position were calculated from the digital elevation model (DEM) data having a comparable spatial resolution with the SAR data. Local incidence angle between the incoming microwave and the surface normal to terrain slope was selected as a primary geometric factor to analyze and to correct the radiometric distortions. Using digital maps of forest stands, several fields of rather homogeneous forest stands were delineated over the SAR image. Once the effects of local incidence angle on the radar backscatter were defined, the radiometric correction was performed by an empirical fuction that was derived from the relationship between the geometric parameters and mean radar backscatter. The correction effects were examined by ground truth data.

• Journal of the Korean association of regional geographers
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• v.22 no.4
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• pp.875-886
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• 2016

The eastern coast of Seopo-myeon, Sancheon-si in the South Coast is a bay almost completely separated from open sea by Changseon and Namhae Islands. Marine terraces in this area can be classified into geomorphic surfaces with elevations of 10~12m, 15~18m, 20~24m, 25~28m, 30~33m, 35~38m, 40~45m, 45~50m and 54m. This marine terrace system is similar to the Boryeong area in the West Coast. The geomorphic surfaces distribute along ridges and show relatively small areas. The young and old surfaces show a mixed distributional pattern. This distributional pattern contrasts to the East Coast where the oldest surface farthest from the coastline is parallel to the coast and age of the surfaces increases with a distance from the coast. These seem to result in high energy waves by typhoon that developed wave-cut platform on hill areas with relatively complex relief in a short time.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2010.06a
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• pp.281-282
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• 2010

우리나라의 수직기준은 인천만의 평균해수면으로 이 높이를 기준으로 수준점의 표고를 결정한다. 현재 우리나라 수준점의 고시성과는 실제 중력의 영향을 고려하는 대신 정규중력식에 의한 타원보정량을 계산하여, 높이차를 보정한 뒤 수준원점을 고정하고 최소제곱법을 수행하여 산출한 정규표고이다. 하지만 우리나라의 경우 산지가 많아 지형의 기복이 심하고 산맥을 가로지르는 수준노선이 있어 중력에 의한 영향을 무시할 수 없으나 현재 그 영향을 고려하고 있지 못하고 있는 실정이다. 따라서 본 연구에서는 항공 중력데이터를 이용하여 수준점의 중력값을 산출한 뒤 정표고를 산출하여 현재 사용하고 있는 고시좌표와 비교해 보고자한다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.22 no.2
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• pp.117-125
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• 2004

This paper describes the orthometric correction for determining the orthometric height obtained from height difference by precise leveling or GPS leveling. Five formulas are used to calculate the orthometric correction for two level lines as an examples. Based on the comparison results Strang van Hees' formula that use the surface gravity is better than the others to compute the orthometric corrections on spirit leveling and GPS/Leveling in an area where mean hight is high and terrain relief show high variability. Further research is necessary to improve the results of this study using Mader method, etc..

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.15 no.2
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• pp.215-219
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• 1997

It is very difficult to conduct a tracing survey of a forest fire because the affected area is huge and the topology of the mountain defies access of investigators. As a result, remote sensing technique is used to get consecutive information about the range and ecological change of the affected area. Therefore, this study investigates the change of activity condition of vegetation by getting vegetation index, hinted by the fact that activities of plants decline after the fire.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2003.04a
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• pp.139-144
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• 2003

3차원 이상의 공간정보의 생성은 우리가 살아가는 현실공간을 입체적으로 조망해 볼 수 있는 가장 일반적인 요구사항이 되었고, 이를 여러 분야에서 다각적으로 활용하려는 연구가 활발히 진행되고 있다. 또한 3차원 이상의 조건을 부여하여 시공간에서 동영상으로 보여주기 위하여 3차원 지형 시뮬레이션을 제작할 수 있는 기술이 보편화 되고 있어 건설분야에서도 적극적인 도입으로 각종 공사계획 및 설계에 이용할 예정이다. 본 연구에서는 이러한 지형공간데이터의 생성을 위하여 원격탐사 데이터와 수치지형도를 이용하여 우리나라 3차원 데이터의 자성 방법과 그 결과를 비교하였으며, 그 결과 DEM에 의한 3차원 수치 기복영상과 위성영상의 합성에 의한 퓨전 영상의 3차원 적용을 통하여 향후 고해상도의 적용시 발생할 수 있는 입체영상의 문제점등을 사전확인 할 수 있었다.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2010.10a
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• pp.131-135
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• 2010

우리나라는 산림이 울창하고 가연성 낙엽 등의 가연성 물질들이 많이 쌓여 있으며, 경사가 급하고 기복이 많은 산지로서 초기진화 실패 시 연소진행 속도가 빨라 급속히 확산 시키는 산악 형 산림으로서 산불 발생 시 진화가 어려워 산불의 확산 속도와 강도를 추정하기 어려운 실정이다. 현재 산불이 발생과 동시에 초기 진화에만 초점을 마치고 있는 시점에서 초기 진화에 실패했을 경우 산불이 확산되는 경로와 시간 등을 예측하여 최소한의 인력과 장비를 이용하여 진화하는 시스템을 구축할 수 있는 경우는 아직 우리나라에서는 미흡하다. 본 연구에서는 특정지역의 국부지형 기상인자(풍향, 풍속)를 측정하여 산불이 발생 시 인자별 특성에 따라서 산불의 진행 경로와 산불의 진화 시나리오를 예측할 수 있는 시스템을 구축하는데 그 목적이 있다.

• Journal of The Geomorphological Association of Korea
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• v.23 no.3
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• pp.27-39
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• 2016

This study statistically investigates relationships between physical properties of rocks and topography by measuring and analyzing section, topographical and measured parameters of 58 bedrock outcrops at areas covered by gneiss, schist, granite, andesite, sandstone and limestone in the Korean Peninsula. Multiple linear regression analysis suggests that the joint spacing, joint continuity, weathering grade and maximum joint width of rocks among the measured parameters are related to the topographical parameters with statistical significances. Therefore, this study suggests that rock properties such as joint spacing, joint continuity, weathering grade and maximum joint width seem to greatly influence topography, although various factors can affect topographical parameters.

• Journal of The Geomorphological Association of Korea
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• v.23 no.1
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• pp.1-16
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• 2016

This study estimates relationships between physical and chemical weathering indices of various rock types and topographical relief. Physical weathering properties such as rock strength and joint and chemical weathering indices such as the $SiO_2/Al2O_3$, CIA and WPI were analyzed from 18 rock outcrops in mountain and valley areas consisting of 9 rock types. The results indicate that the elevation and relief of topography increase physical strength of rock increases. It can be suggested that the total r(rock-mass strength rating) and R(rock rebound strength by Schmidt Hammer) are most useful indices as a quantitative weathering property factor to explain formative causes of topographical relief. The results also suggest that rock types such as sandstone, granite, gneiss and schist are most suitable to explain meaningful difference in topographical relief with the physical and chemical weathering indices.

• Economic and Environmental Geology
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• v.55 no.5
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• pp.541-550
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• 2022

A pre-existing landform is created by weathering and erosion along the bedrock fault and the weak zone. A neotectonic landform is formed by neotectonic movements such as earthquakes, volcanoes, and Quaternary faults. It is difficult to clearly distinguish the landform in the actual field because the influence of the tectonic activity in the Korean Peninsula is relatively small, and the magnitude of surface processes (e.g., erosion and weathering) is intense. Thus, to better understand the impact of tectonic activity and distinguish between pre-existing landforms and neotectonic landforms, it is necessary to understand the development process of pre-existing landforms depending on the bedrock characteristics. This study used a two-dimensional numerical landscape evolution model (LEM) to study the spatio-temporal development of landscape according to the different erodibility under the same factors of climate and the uplift rate. We used hill-slope indices (i.e., relief, mean elevation, and slope) and channels (i.e., longitudinal profile, normalized channel steepness index, and stream order) to distinguish the difference according to different bedrocks. As a result of the analysis, the terrain with high erosion potential shows low mean elevation, gentle slope, low stream order, and channel steepness index. However, the value of the landscape with low erosion potential differs from that with high erodibility. In addition, a knickpoint came out at the boundary of the bedrock. When researching the actual topography, the location around the border of difference in bedrock has only been considered a pre-existing factor. This study suggested that differences in bedrock and various topographic indices should be comprehensively considered to classify pre-existing and active tectonic topography.