• 한국농공학회:학술대회논문집
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• 한국농공학회 2005년도 학술발표논문집
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• pp.423-428
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• 2005

If the load of constructing vehicles during the construction work acts on the road or the ground surface on the soft ground, due to the excess stresses in soils the trafficability of the vehicles influences the constructing efficiency, constructing period and so on. Stress distribution in soils is the very important element to design and to solve the problems of settlement, safety of foundations and trafficability of constructing vehicle in civil engineering. This research represents the comparative estimation of the actual and theoretical measurement on the underground stress of outer layer for each soil after the observation of each top soil layer for its vertical and horizontal stress in (1)homogeneous sand ground (2) weak stratum with the sand soil (3) weak stratum with gravel of the soil model, and it also investigates the effect of subsidence of ground by the repeated load. The underground stress turn out to be different in the value of theoretical and actual measurement after the trial examination of model.

• 기술사
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• 제10권2호
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• pp.13-26
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• 1977

The Kum-Ho river basin is one of the densely populated area having more than 35% of the total population and it was also well irrigated since ealier days in the Nackdong River Basin Most of the easily developed source of surface water are fully utilized, and at this moment the basin is at the stage that no more surface water can be made available under the present rapid development of economic condition. Since surface water supplies from the basin have become more difficult to obtain, the ground water resources must be thoroughly investigated and utilized greatly hereafter. In economic ground of the basin what part could ground water play\ulcorner In what quantities and, for what uses could it be put\ulcorner The answer to these questions can be relatively simple; the ground water resources in the basin can be put at almost any desired use and almost anywhere in the basin. The area of the basin is at about 2088km$^2$ in the middle part of Nackdong River Basin and it is located along the Seoul-Pusan Express Highway. The mean annual rainfall is about 974.7m/m, most of which falls from June to September during the monsoon. Accumulated wet period is appeared approximately after every 8 year's accumulated dry-period with the duration of 5 years. The water bearing formations in the basin include unconsolidated alluvial deposits in Age of Quatenary, saprolite derived from weathered crystalline rocks, Kyongsang sedimentary formations of the period from late Jurassic to Cretaceouse, and igneouse rocks ranging of the Age from Mesozoic to Cenozoic. The most productive ground water reservoir in the basin is calcareouse shale and sandstones of Kyongsan system, which occupies about 66% of the total area.

• 한국표면공학회지
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• 제54권4호
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• pp.209-214
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• 2021

As coffee consumption per person increases annually to 323 cups in 2018, treating the spent coffee ground has arisen because spent coffee ground results in soil and air pollution. The demands of air purification filters are increasing more and more because the air pollution due to the fine dust has become worse. The spent coffee grounds had a porous structure, however, the pore was blocked by organic oil compounds. Electrocoagulation, which is one of the electrochemical methods, has the potential to remove the organic compounds. The surface area of spent coffee grounds increased effectively after the electrocoagulation treatment, and surface morphology and surface area were confirmed using SEM and BET, respectively. Using the FT-IR, both the spent coffee grounds and the electrocoagulated spent coffee grounds were characterized. The filter characteristics were examined by the adsorption test using formaldehyde, one of the air pollutants.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 A
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• pp.290-292
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• 2003

The intake tower of D-dam located in a mountainous area positioned in the left side of the dam and its structure installed alone on the water surface then, can become target of direct lightening. To protect the intake tower from the direct lightening and indirect-lightening, lightening rod installed in the top area of the intake tower and ground pole laid under the surrounding ground. however, because the surrounding ground almost consists of a rock, it is very difficult to obtain the grounding resistance. It is main object to examine the construction plan of the optimum lightening rod equipment and ground pole with measuring the earth specific resistance of the around of the intake tower which is the scheduled area to lay the ground pole with the Wenner's 4-electric pole method and the Schlumberger's method. and using the analysis tool, ESII.

• 한국지반환경공학회 논문집
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• 제23권8호
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• pp.17-22
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• 2022

공용 중에 연약지반의 침하로 발생된 교량 접속부의 단차 개선을 위해 도로관리기관에서는 지속적으로 덧씌우기를 실시하고 있다. 본 연구에서는 연약지반 내에 건설된 교량 9개소에 대해 접속부의 침하량을 추정하고자 1GHz 안테나를 차량에 탑재한 지표투과레이더 장비를 이용하였다. 포장 내부 조사가 가능한 지표투과레이더 기술로 아스팔트 도로에서 깊이 1m 수준까지 효과적으로 포장두께의 측정이 가능하였다. 노면 변형 조사결과와는 다르게, 9개 교량 접속부에서 측정된 포장두께 변화량은 최소 50mm에서 최대 600mm로 상당하였으며, 공동(空洞)의 발생 가능성도 높았다. 또한 각 교량 접속부의 부위별로는 증가된 포장두께의 차이가 50~250mm로 나타나 부등침하 위험이 존재하였다. 본 연구에서 지표투과레이더 결과에 근거하여 주행성 개선 및 침하부 유지관리 방안을 제시하였다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.798-800
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• 2003

The time shift processing of ground measured surface temperature with the meteorological variables has no evaluated function. We introduce new evaluating function. To use this evaluating function, the algorithm of time-shift processing will be able to be reliable and get error-bar for all moving measured point's data. We will finally obtain the area averaged surface temperature by land observation.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 가을 학술발표회 논문집
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• pp.45-56
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• 1999

There have been many coal mines abandoned since late 1980s in Korea. Due to the abandoned mines, there have been ground subsidences in some area where are under ground reinforcement works now. So, this study shows the general phenomena of mining subsidence and the procedure of ground reinforcement. In general the procedure for ground reinforcement is as below, 1) obtaining information from inquiries and observations, 2) satellite image analysis and surface geological mapping, 3) analysis of maps of coal mines, 4) geophysical survey and boring test and 5) selection of reinforcement method. The case of reinforcement design at Chul-am area, Kangwon Province is introduced in this article.

• 한국환경과학회지
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• 제13권8호
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• pp.721-731
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• 2004

The dispersion of suspended particulates in the coastal complex terrain of mountain-inland basin (city)-sea, considering their recycling was investigated using three-dimensional non-hydrostatic numerical model and lagrangian particle model (or random walk model). Convective boundary layer under synoptic scale westerly wind is developed with a thickness of about I km over the ground in the west of the mountain, while a thickness of thermal internal boundary layer (TIBL) is only confined to less than 200m along the eastern slope of the mountain, below an easterly sea breeze circulation. At the mid of the eastern slop of the mountain, westerly wind confronts easterly sea breeze, which goes to the height of 1700 m above sea level and is finally eastward return flow toward the sea. At this time, particulates floated from the ground surface of the city to the top of TIBL go along the eastern slope of the mountain in the passage of sea breeze, being away the TIBL and reach near the top of the mountain. Then those particulates disperse eastward below the height of sea-breeze circulation and widely spread out over the coastal sea. Total suspended particulate concentration near the ground surface of the city is very low. On the other hand, nighttime radiative cooling produces a shallow nocturnal surface inversion layer (NSIL) of 200 m thickness over the inland surface, but relatively thin thickness less than 100m is found near the mountain surface. As synoptic scale westerly wind should be intensified under the association of mountain wind along the eastern slope of mountain to inland plain and further combine with land-breeze from inland plain toward sea, resulting in strong wind as internal gravity waves with a hydraulic jump motion bounding up to about 1km upper level in the atmosphere in the west of the city and becoming a eastward return flow. Simultaneously, wind near the eastern coastal side of the city was moderate. Since the downward strong wind penetrated into the city, the particulate matters floated near the top of the mountain in the day also moved down along the eastern slope of the mountain, reaching the. downtown and merging in the ground surface inside the NSIL with a maximum ground level concentration of total suspended particulates (TSP) at 0300 LST. Some of them were bounded up from the ground surface to the 1km upper level and the others were forward to the coastal sea surface, showing their dispersions from the coastal NSIL toward the propagation area of internal gravity waves. On the next day at 0600 LST and 0900 LST, the dispersed particulates into the coastal sea could return to the coastal inland area under the influence of sea breeze and the recycled particulates combine with emitted ones from the ground surface, resulting in relatively high TSP concentration. Later, they float again up to the thermal internal boundary layer, following sea breeze circulation.

• Spatial Information Research
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• 제16권3호
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• pp.373-383
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• 2008

지표면에 대한 정보를 취득하는 기법 중 지금까지 주로 사용되어온 기법은 항공사진 및 위성영상과 같이 평면적인 정보 수집에 중점을 두고 있는 반면, 본 논문에서 다루는 LiDAR(Light Detection And Ranging)는 레이저 측량기술을 이용하여 지표면에 대한 고해상도의 비정규분포 Point 형태의 3차원 정보의 획득이 가능하다. GPS(Global Positioning System) 수신기와 INS(Inertial Navigation System)의 결합을 통해 좌표 값을 제공하게 된다. 이러한 LiDAR의 3차원 Point 정보와 좌표 값을 활용하여 보다 정밀한 3차원 모델링 수행이 가능하다. 본 연구에서는 LiDAR의 반사강도와 기하/지형 자료를 이용하여 도시지역을 대상으로 정밀한 3차원 공간정보자료를 취득하고, 그 자료를 분석하여 도시지역을 높이와 밀도를 기반으로 하여 3차원으로 분류하였다. LiDAR를 통해 획득된 원시자료로부터 지표면에서 반사되는 Point Data의 개수를 지면과 비지면 요소의 비율로 추정하여 지형과 공간적 특성을 파악하고 이에 따라 3차원 토지피복분류도를 작성하였다. 신호의 강약을 구분하는 기준은 통계적 방법(Jenk's Natural Break)을 통해 추정된 값을 사용하였으며, 지표면 반사비율에 따라 세부지역으로 구분하여 크게 고밀도 저밀도 식생지역과 비식생지역으로 구분하였다.

• 한국안전학회지
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• 제7권4호
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• pp.55-61
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• 1992

An engineer designing a tunnel in an urban area should be to predict the magnitude and distribution of ground movements which are important to Investigate the potential damage to the existing structures around tunnel. The present study examines available theories and emprical equations, and tries to investigate quantativily ground movements around tunnel with tunnel progressing. Approcaches to the problem of ground movements associated with twin tunnel was and elasto - plastic finite element method. Typical section in Seoul Subway were selected in numerical study. The analysis and study was done with respect. to surface, subsurface and crown settlements with varying ground conditions, tunnel geommetry and construction conditions.