• Proceedings of the KSRS Conference
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• 2007.03a
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• pp.292-295
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• 2007

개발계획이나 환경계획 수립시에 절대적인 해발고도를 기준으로 지형적 특성을 분석한다면 절대표고가 낮은 지역은 대부분 개발가능지로 구분된다. 따라서 지역적 특성을 반영하는 상대표고를 적용하여야 하나 산의 경계구획，능선설정 등의 어려움으로 아직 전국단위의 구체적인 연구는 미흡한 실정이다. 이에 본 연구에서는 최근 Weiss 가 제안한 지형위치지수 ( Topogr aph i c Position Index, TPI) 를 적용하여 전국 단위의 상대표고 분석 가능성을 검토하였다. TPI 모델 도출 결과와 기존 환경부 국토환경성 평가에 사용한 Gaia EZeye 모델 결과를 중첩 비교한 결과 정확도가 높은 것으로 나타났다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.34-35
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• 2018

낙동강 하류역은 최근의 퇴적우세 지형변화와 더불어, 기후변화에 따른 태풍강도 강화 등으로 인한 해일고 증가가 우려된다. 따라서, 과거 태풍자료를 수집 분석한 후 연구지역에 가장 큰 영향을 미친 태풍을 모델 태풍으로 선정하여 낙동강 하류역에 위치한 주요지점별 폭풍해일고 변화를 파악하였다. 실험결과, 최대 폭풍해일고는 태풍 매미 내습시에 나타났으며, 하단 매립지 전면에서 1.1~1.5m, 명지주거단지 전면에서 1.2~1.3m, 녹산국가산업단지 전면에서 1.3~1.5m로 하단 매립지 전면이 가장 크게 나타났다. 향후, 과거 지형변화를 고려한 폭풍해일고 검토를 통하여 최근의 급격한 지형변화로 인한 영향을 파악한 대비를 해야 할 것으로 사료된다.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.862-865
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• 2012

유사량은 하천의 단면을 단위시간 동안 통과하는 토사의 양을 의미하며, 하천 구조물의 설계 및 유지관리를 위한 기본자료로 활용된다. 유사량은 하천 유역의 지형적인 특성과 기상요소에 영향을 받으며, 이를 규명하기 위한 많은 연구들이 수행되어 왔다. GIS기반의 유사량 예측모델로서 국내에서는 개정범용토양유실공식과 유사운송비(Sediment Delivery Ratio)를 이용하여 유역단위 유사량을 예측하는 연구가 이루어져왔다. Gavrilovi$\acute{c}$ 모델은 유역의 총 연유사량을 예측하고 토양침식의 정도를 정량화할 수 있는 경험적 모형으로 지질 및 토양, 지형조건, 기후인자(연평균 강우량, 연평균 온도), 토지이용의 6가지 입력변수로 구성되어 있다. 본 연구는 Gavrilovi$\acute{c}$ 모델의 국내 적용성을 검토하기 위한 것으로서, 왕숙천 유역을 대상으로 Gavrilovi$\acute{c}$ 모델을 적용하여 유사량을 산정해본 결과, 실측값을 약 20% 내외로 비교적 근사하게 추정할 수 있음을 알 수 있었다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.4 no.1
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• pp.43-48
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• 1986

To improve the accuracy of the interpolation point of the digital terrain models, this paper compared the methods of terrain data acquisition and the equations of the curved surface

• Aerospace Engineering and Technology
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• v.11 no.1
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• pp.118-125
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• 2012

The purpose of this study is to analyze the ortho image quality change according to the generation technique of Digital Elevation Model(DEM) based on the digital map. First of all, two different types of DEM were generated using contour layer(Case1), contour layer and altitude layer(Case2) from the digital map on the scale of 1/5,000. After generating and evaluating two types of DEM, KOMPSAT-2 ortho images were generated by using them. In conclusion, Case2 DEM was more effective to use in the slope and switchback area, on the other hand, Case1 DEM was much better than Case2 DEM for preventing a topographic distortion in flat area.

• 한국해양학회지
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• v.30 no.6
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• pp.565-583
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• 1995

We have used a nonlinear quasi-geostrophic model to study effects of lateral friction and bottom topography on the motion of warm eddies. The two empirical orthogonal functions of the stream function, accounting for the vertical structure, represent the barotropic and first baroclinic dynamic modes. This model is integrated 360 days on a 1000 km ${\times}$ 1000 km domain with a resolution of 10 km ${\times}$ 10 km including both the thermocline and idealized topography of the East Sea. Prescribed inflow through the Korea Strait is compensated by outflow through the Tsugaru Strait. The balance between the nonlinear advection term and the planetary ${\beta}$-effect tends to make northward movement of warm eddy over a flat bottom. The motion of a warm eddy over a sloping topography can be dominated by the nonlinear advection, while nonlinearity plays a secondary role over a flat topography. For eddies dispersing over topography, the nonlinear tendency is a function of time. For a strong warm eddy, northward propagation can occur. For intermediate strength of eddies one might expect a balance between the nonlinear term and the topographic ${\beta}$-effect. As nonlinearity decreases with eddy dispersion, southward motion along the slope may occur by such as a topographic Rossby wave. Our numerical simulations have confirmed the importance of lateral friction on eddy motions, in such a way that the northward penetration of the warm eddy increases drastically by the decrease of the lateral friction. The northward motion of warm eddy can be prevented by reducing the Reynolds number sufficiently. We have also demonstrated the crucial role of topographic effects in the eddy motion process.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.8 no.2
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• pp.45-51
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• 1990

DEM must have a high accuracy against the actual topographic model. A model which can compute heights responding to random plane position by using of the topographic data and interpolation must be constructed. Interpolation affected by the accuraccy of the observations included noise, which affected by the slop and curvature weight. Data smoothing is a method to reduce the noise. Average declination and area ratio are variable which result similarity in according to slope. But in local area, area ratio well shows a local change. This study try to classify the terrain by the declination to analysis the effects of the declination and curvature weights, and then to represent the most probable model. The result are following : In terrain classification by the slop, p16 and p24 were fitted in the plane surface fit p16 and S in the varying surface, and S and p24 in the irregular surface in classification by curvature, p24 and S were fitted in the plane or varying surface, and p16 in the irregular surface In case of hybrid, p16, p24 and S are fitted in the plane, varying and irregular surface respectively. Smoothing is the most effective in case of slope of 50 persentage and of curvature weight of 0.0015.

• The Transactions of the Korea Information Processing Society
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• v.5 no.9
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• pp.2281-2293
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• 1998

Spatial objects in the space II odd hale been changed bl eitber non-spiltial operations or spatial operations. For example, their states arc changed by the following operation: changing their owners, changing their owner's address, installing new constructions, changing precincts, splitting, and merging, The conventional geographic information system(GIS), however, did not also manage their histoncal information cecause it handles the snapshot image of spatial ohjects in the world. In this paper we therelore propose a spatiotemporal data model which is ahle to not un]y manage the historical information of spatial objects but also, support their historical intemlgation by extending a time dimension and a historical pointer for SDE(Spatial Database Engine) spatial data model. Finally, the proposed spatiotemporal data model using a layered time extension are going to contribute to manage the history of spatial objects in the world and retrieve them.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.13 no.2
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• pp.277-283
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• 1995

In the study, an accuracy of earthwork volume is evaluated according to different methods of the calculation with different criteria. The criteria applied to this study are a interpolation method, a grid intavals and the method of earthwork evaluation. A numerical test has performed on two different terrain models with four different methods of calculation in the earthwork volume and two different grid intervals. The end area method, prismoidal formular, Simpson's formular, and middle area method are applied to the calculation of the earthwork volume. As a result of this study, it is showed that the moving average method with the first order term gives the most accurate result in interpolation, and that also the prismoidal formular and Simpson's formular gives more accurate result than average and area method and middle area method in the calculation of earthwork volume.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.8 no.1
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• pp.31-40
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• 1990

In this study, sample area was selected to compare the conventional method with photogrammetic method in basic planning of country club. Also various elements of planning, such as vegetation and water system, were considered through interpretation of aerial photographs and topographic maps, vegetation maps and water system maps were made as well as digital terrain models. These were used to analyse tophographic changes and landscape. As a result of comparing with the conventional method, it was shown that photographic interpretation could give more detail values than the conventional method, and that the digital terrain model could predict changes of topography, landscape and water system with more asccuracy. Consequently, the method of digital terrain model and photographic interpretation proved to be more effective than the conventional method in the case of water treatment, and planning of landscape and land utility.