• Journal of Korea Water Resources Association
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• v.40 no.6 s.179
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• pp.431-446
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• 2007

Groundwater flow in a basin is greatly affected by many hydrogeological and hydrological characteristics of the basin. A groundwater flow model for the Kap-cheon basin ($area=648.3km^2$) in the Geum river basin was established using MODFLOW by fully considering major features obtained from observed data of 438 wells and 24 streams. Furthermore, spatial groundwater recharge distribution was estimated employing accurately calibrated watershed model developed using SWAT, a physically semi-distributed hydrological model. Model calibration using observed groundwater head data at 86 observation wells yielded the deterministic coefficient of 0.99 and the water budget discrepancy of 0.57%, indicating that the model well represented the regional groundwater flow in the Kap-cheon basin. Model simulation results showed that groundwater flow in the basin was strongly influenced by such factors as topological features, aquifer characteristics and streams. The streams in mountainous areas were found to alternate gaining and losing steams, while the streams in the vicinity of the mid-stream and down-stream, especially near the junction of Kap-cheon and Yudeong-cheon, areas were mostly appeared as gaining streams. Analysis of water budget showed that streams in mountainous areas except for the mid-stream and up-stream of Yudeong-cheon were mostly fed by groundwater recharge while the streams in the mid and down-stream areas were supplied from groundwater inflows from adjacent sub-basins. Hence, it was concluded that the interactions between surface water-groundwater in the Kap-cheon basin would be strongly inter-connected with not only streams but also groundwater flow system itself.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.80-80
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• 2015

만곡부가 연속적으로 발생하는 사행하천은 만곡의 영향으로 2차류가 발생한다. 이러한 2차류의 영향은 하상변동, 제방침식 등의 문제를 발생시켜 사행수로의 흐름특성을 분석하기 위한 많은 연구들이 진행되어 왔다. 하지만, 대부분의 연구들은 실규모 하천의 유속측정의 어려움, 측정이 가능한 시설 및 경제적 제한으로 인해 주로 실내실험에서 측정된 자료를 이용하여 분석을 수행하여 흐름조건이 상이한 실제 하천에서 적용성에 한계가 있어 왔다. 본 연구에서는 상세한 3차원 유속 측정이 가능한 최신 계측기기인 초음파도플러유속계(ADCP)를 활용하여 실제하천과 유사한 흐름 상태 및 지형을 재현한 한국건설기술연구원 안동하천실험센터의 사행도 1.2, 1.5, 1.7의 실규모 사행수로에서 횡단면 측정을 수행하였다. 또한 초음파지점유속계(ADV)를 사행도 1.2의 ADCP 측정 단면과 동일한 횡단면에서 측정하여 공간평균된 ADCP 유속자료를 이용한 흐름패턴 분석의 적용성을 검증하였다. 그 결과 공간평균된 ADCP 유속분포는 시간평균한 ADV 유속분포와 다소 크기의 차이는 발생하였지만 패턴은 매우 유사하게 나타났다. 따라서, 공간평균된 ADCP 유속분포를 이용하여 2차류에 의한 흐름패턴 분석을 수행하였다. 2차류 패턴은 만곡의 위치에 따라 매우 복잡한 형태로 나타났다. 2차류에 의한 최대유속선과 최대수심선의 발생위치를 분석한 결과, 만곡의 정점부를 기준으로 만곡 전인 유입부에서는 이격되고 만곡 후인 유출부에서는 유사한 경로를 나타내고 있었다. 이때의 2차류강도(Secondary Current Intensity; SCI)는 만곡의 정점부 부근에서 최대로 증가했다가 다시 감소하는 결과를 보였다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.23 no.3
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• pp.293-301
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• 2005

In case of the roads that pass the mountain area, the cut sections or the tunnels are constructed. And In winter season it appears sunshine few in the specific segment, the shade is continued last and the freezing sections occur. So, the attention is necessary in traffic safety. This study was to evaluate the influence of sunshine and surface freezing sections expected in route plans of roads using GIS and makes alternative ideas in road stability security. After selecting 29 km sections of Donghae highway and creating a 3 dimensional terrain surface through the digital conversion of design plan data, it reflects the road alignment data of the same coordinates and a 3 dimensional road modeling is created. It set shadow time of road surface for the solar trace in the winter solstice in 20 minute interval. Shade areas are displayed and inputed in polygon data by manual vertorizing. Graphic and attribute data of this shade section is constructed in geodatabase of ArcCatalog. And it extracted the freezing section using intersect fuction of the GIS spatial analysis. By analyzing the winter meteorological data of temperature, rainfall, snowfall, humidity, and etc. and grasping dangerous freezing section of the road surface effectively, it will be able to make alternative ideas of the preliminary stability evaluation reflected in basic design.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.5 no.4
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• pp.271-278
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• 1993

Sand ripple. the smallest bottom configuration, is one of the most important factors in the mechanism of sand transport. This paper deals with characteristics of ripple geometry generated by regular and irregular waves. Especially. rearrangement of ripple spacing caused by increasing or decreasing waves is investigated through movable bed experiments. Nondimensional length of rearranged ripples becomes very close to that of measured ripples in the field Furthermore, stochastic characteristics and occurrence limits of three dimensional ripples are investigated through the wave number spectrum calculated from the measured bottom topography.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2010.06a
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• pp.105-109
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• 2010

전 세계적으로 육상자원의 고갈로 해양광물을 개발하고 이를 경제적으로 활용하려는 움직임이 점점 증가하고 있다. 이에 우리나라도 한반도 주변 해역의 해양광물자원을 확보하기 위한 탐사와 연구가 진행 중에 있다. 특히 우리나라는 삼면이 바다로 둘러싸인 지형학적 특정으로 주변국과의 자원경쟁이 불가피하여 전략적 체계적 탐사자료의 관리와 이를 활용하기 위한 방안이 필요하다. 하지만 탐사 분야가 다양하고 그에 따른 데이터가 상이하여 관리에 어려움이 있다. 현재 국내에서 해양자원에 대한 정밀탐사가 이루어지고 과학적인 정보제공이 요구됨에 따라 해양광물자원정보시스템이 구축 운영되고 있지만 몇 가지 제약점이 존재한다. 따라서 본 연구에서는 이를 보완하기 위해 특히 시추 퇴적물 탐사 분야에 있어 GIS기반의 표출 가능한 대상항목을 분류하였고, 데이터베이스 구축을 위한 모델링을 진행하였다. 이는 위치기반의 분석결과 자료를 제시할 수 있도록 하였다 본 연구는 해저 퇴적층에 분야의 과학적 정보 제공을 위한 기반을 마련하였다는데 의의가 있다. 또한, 한반도 주변에 해양광물자원의 부존 가능 지역을 파악하는데 있어 과학적 정보를 지원하고 나아가 광물자원의 매장량 추정이나 경제성 평가를 위한 정보제공의 기반이 될 것으로 사료된다. 향후 연구에서는 시추퇴적물의 깊이에 따른 데이터베이스 관리 방안과 더불어 3차원 정보 제공에 대한 연구와 모델링 결과를 통해 실제 데이터에이스 구축이 진행되어야 할 것이다.

• Journal of Satellite, Information and Communications
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• v.8 no.1
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• pp.40-44
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• 2013

In this paper, we describe on the position error of GBAS. In reality, there are many sources which make errors into the calculation of receiver position. It is well known that the DOP of GBAS is an important position error source and is dependent on the numbers and positions of the transmitters. Here, we develop an algorism to calculate the DOP of the GNSS with 2-line transmitters into Korean area. The result is useful to predict the DOP of the positions where transmitters and receivers are located.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.25 no.5
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• pp.407-414
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• 2007

Even Korea is big country of automobile, the occurrence of traffic accident is in last place in 29 OECD countries. If it is evaluated by assessment guide of investment over the development project of public-traffic facilities, it was shown that the direct economical loss was fairly great. In this study, in order to minimize the traffic accidents occurring at curve area of road, it was tried to establish the standard of non-passing distance. The close-range photogrammetry was used and three dimensional modeling was fulfilled. Currently, this paper was focused on presenting the standard of road design with analyzing the internal and external standard of non-passing distance.

• Land and Housing Review
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• v.13 no.1
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• pp.113-129
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• 2022

A building's eco-friendliness is directly related to various values including the life cycle cost of a building. However, the conventional architectural design method has a limitation in that it cannot create an optimized case according to the surrounding environmental conditions. Therefore, the purpose of this research is to present a design assistance tool that can review planning cases optimized for the environmental conditions of the building site in the planning stage of architectural production. To achieve the purpose of the study, an algorithm for realizing 3D modeling of the region and analysis of the solar environment was produced based on the site contours, building, and road information from the digital topographic map provided by the National Geographic Information Institute. To examine the validity of the developed algorithm, a comparative experiment was conducted targeting the elevation direction of the existing building. As a result, it was found that the optimal elevation direction selected by the algorithm can receive higher insolation compared to the front facade of the main building.

• Economic and Environmental Geology
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• v.36 no.4
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• pp.305-312
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• 2003

This study was performed to delineate the subsurface geology, geologic structure, and distribution pattern of the Palgongsan granitic body, and to reveal the relationship between the Kyeongsang basin and Yongnam massif by gravity survey. The study area is located between the latitude of 35$^{\circ}$45'-36$^{\circ}$21'N and longitude of 128$^{\circ}$15'-129$^{\circ}$00'E. Total of 966 gravity data measured by Seoul National University, KlGAM(Korea Institute of Geology, Mining ＆ Materials), Pusan National University and Yonsei University were used. The Bouguer gravity anomaly in the study area ranges from -12.88 to 26.01 mgal with a mean value of 11.27 mgal. A very low anomaly zone is located in the Yongnam massif in west of the study area. The anomaly value increases going from west to east. A low anomaly distribution in Palgongsan granite and Yongnam massif is interpreted as the effect of their lower density than that of Kyeongsang Super Group. Power spectrum analysis is applied to evaluate the average depth of basement the Kyeongsang Basin and Conrad discontinuity from gravity anomaly. The average depths of density discontinuities are calculated 10.45 km and 4.9 km, and these are interpreted as Conrad discontinuity and depth of basement of the Kyeongsang Basin, respectively. The depth of Palgongsan granite is derived by means of 2-dimensional modeling and it decreases gradually toward the east. The gravity anomaly east of the study area decreases abruptly due to Shingryeong fault and Nogosan ring fault. Two deepest and sharp roots of Palgongsan granite are recognized by 2-dimensional modeling of each profiles. The depths of those roots are 5.3 km on a profile AA' and 7 km on a profile BB' which is the maximum depth of Palgongsan granite. Small granitic bodies are also seen to be intruded around the Palgongsan granite. The root of Palgongsan granite is shown by 3-dimensional analysis based on the interpolation of 2-dimensional modeling along each profiles to exist in the southwest vicinity of Palgongsan granite. The total volume of Palgongsan granite is approximately 31.211 $Km^3$.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.342-342
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• 2016

국내 저수지 17,477개소 중 30~40 여년전에 축조된 곳은 16,646개소로 95.2%가 노후화로 인한 지속적인 유지보수가 필요하며, 기후변화에 따른 대응능력이 현저하게 낮다. 하구둑, 방조제, 대형 농업용저수지 같은 대규모 농업기반시설들은 축조 당시보다 설계홍수량이 2~3배 이상 증가함에 따라 기후변화에 대비하기 위해 조속한 치수능력 증대가 필요하다. 하지만 대형 농업용저수지의 치수능력 증대를 위해서는 지형적 입지조건, 시공 가능성, 경제성 등을 고려하여 여수로의 위치, 규모, 형식 변경 등이 수반된다. 따라서 본 연구에서는 무한천 상류 예당저수지의 여수로 위치변경에 따른 저수지 하류 하천 흐름변화에 대하여 2차원 수치모의 연구를 수행하였다. 본 연구에서는 TELEMAC-2D 모형을 적용하여 저수지 하류 하천의 흐름을 모의하였고, RMA-2 모의결과와 비교검토 하였다. TELEMAC-2D 모형은 상류(subcritical flow)와 사류(supercritical flow) 흐름 모의가 가능하며, 홍수범람 뿐만아니라 동일 격자망으로 유한요소법과 유한체적법 모두 수치모의가 가능한 특징이 있다. 본 연구에서는 시간과 공간에 대하여 2차 정확도를 가지는 WAF(Weighted Average Flux) 유한체적기법과 $k-{\varepsilon}$ 난류모형을 적용하였다. 수치모의시 유역종합치수계획의 30년, 50년, 100년 빈도 계획홍수량에 대하여 여수로 위치변경 전(CASE-1)과 위치변경 후(CASE-2) 저수지 하류하천 흐름변화에 대해 모의하였다. 본 연구는 국내 하천 특성을 반영한 기설 저수지의 하류하천의 흐름에 대한 수치모의의 기초자료로 활용되어, 저수지 방류 흐름이 하류하천에 미치는 영향 분석 등에 기여할 것으로 기대된다.