• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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• pp.407-410
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• 2006

Studies were performed on evaluating the applicability of activated carbon bugs on dye tracer tests as tracer detectors by using its adsorption isotherm of the grained activated carbon. We preliminary conducted several standard adsorption and extraction tests and obtained the relationship between standard dye solution and detected concentrations from activated carbon samples in dry and wet conditions. the slopes of the regression line were 0.71 for wet condition and 0.74 for dried one. Field dye tracer tests were performed in a karst area, where several faults occur along a stream and pass the test area. We sampled water samples and activated carbon samples at three points in Hwangji Pond, where groundwater outflows from the karst conduit. According to the results of breakthrough curve analysis, the regional flow along the conduit, which is assumed to cause a karst conduit, was estimated as 0.18 m/day. The relationship between the concentrations of water sample and extracted activated carbon bugs shows the similar slopes with those from standard solution tests. This suggests that activated carbon could be useful as a dye tracer detector because the extraced concentration can be quantified.

• Geomechanics and Engineering
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• 제36권5호
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• pp.441-453
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• 2024

Sinkhole subsidence and collapse is a common geohazard often formed in karst areas such as the state of Florida, United States of America. To predict the sinkhole occurrence, we need to understand the formation mechanism of sinkhole and its karst hydrogeology. For this purpose, investigating the factors affecting sinkholes is an essential and important step. The main objectives of the presenting study are (1) the development of a machine learning (ML)-based model, namely C5.0 decision tree (C5.0 DT), for the prediction of sinkhole susceptibility, which accounts for sinkhole/subsidence inventory and sinkhole contributing factors (e.g., geological/hydrogeological) and (2) the construction of a regional-scale sinkhole susceptibility map. The study area is east central Florida (ECF) where a cover-collapse type is commonly reported. The C5.0 DT algorithm was used to account for twelve (12) identified hydrogeological factors. In this study, a total of 1,113 sinkholes in ECF were identified and the dataset was then randomly divided into 70% and 30% subsets for training and testing, respectively. The performance of the sinkhole susceptibility model was evaluated using a receiver operating characteristic (ROC) curve, particularly the area under the curve (AUC). The C5.0 model showed a high prediction accuracy of 83.52%. It is concluded that a decision tree is a promising tool and classifier for spatial prediction of karst sinkholes and subsidence in the ECF area.

• 동굴
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• 제16권17호
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• pp.27-33
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• 1988

석회동굴의 분포는 석회암지대에 존재하기 때문에 Karst 지형의 분포와 밀접한 관계가 있다. Karst 지형은 1893년 유고슬라비아의 J.Cvijic에 의해서 Istria에서 Kotoor지역에서 최초로 보고되었다. 세계의 주요 카르스트지형의 분포지를 보면 Yugoslavia의 Karst지방 남부, France의 Causs지방, Espania의 Andalusia지방, 그 밖에 Greece와 북부 Yucatan반도, 중앙 America의 Jamaica와 Puerto Rico와 Cuba의 북부지역 그리고 북부 Great Australian Bight 부근의 해안평야, 미국의 Florida 반도의 중부와 Great Valley, Indiana 남부 Kentucky의 각지의 Tennessee 중서부, 그리고 영국의 중앙북부인 백악지방, 중국의 화남지방, Thailand, Vietnam, Burma, Celebes 남부, Java, 일본의 추길대지방과 평미대지역 등이다.(중략)

• 동굴
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• 제40권
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• pp.13-29
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• 1994

지리정보체게 (GIS. Geogrphi Information Systems) 는 컴퓨터를 이용한 지구공간체의 제 사상을 과학적으로 처리하는 고차원적인 공간 기법인 것이다. 연구목적은 다양한 지표와 지하시스템에 관한 종합적인 연구에 있어서, 자연지물에 대한 삽화와 표 등을 동반한 기술에 의존해온 기존의 방식을 탈피하고, 고도의 3차원적인 묘사방법인 지리정보체계에 관한 기법을 도입적용하여, 지표와 지하 카르스트(Karst)연구의 과학화를 주도하며, 지역사회의 발전에 기여함을 그 목적으로 한다.(중략)

• 동굴
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• 제36권37호
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• pp.103-113
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• 1994

Slope soil formation and its attributes in southwestern Wisconsin are potentially important due to its origin, landscape position and karstic backgrounds (Oh, 1990). Since French explorers and missionaries reached in southwestern Wisconsin in the 1830's, the loess mantled karst upland surfaces, consisted of forests: timberland, oak openings, and prairie, had been cultivated. At present, nearly 90% of the ridge land is in farms. Karst soils are usually reddish clayey features (Oh and Day, 1989).(omitted)

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 봄 학술발표회 논문집
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• pp.399-406
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• 1999

Recently, the construction of the several highway bridges in the karst area have encountered severe problems associated with cavities and sinkholes. To solve this problems, it is important to understand the distribution characteristics of cavities in the construction site on limestone area. This paper briefly describes the different types, the distribution control factors and the infill sediment types of lime-cavities in the study area, bridge site in the karst area and propose the effective method of survey design. Cavity system may be divided into two main groups, 1)'slot and cave system'and 2)'sinkhole and cave system'. And the shape, the size and the distribution pattern of cavity are controlled by three main factors - rock type, geological structure and ground water condition. Additionally, infill sediment may be considered as one of the important design factors for foundation design and divided into four types by sediment properties. There are geophysical thechnics and geologic survey and drilling test, etc. by the survey method to interpretate characteristics of cavity system, and this methods are optimally designed at the site investigation stage.

• Membrane and Water Treatment
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• 제13권6호
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• pp.303-312
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• 2022

The natural hydrology and geological conditions of Xintian County was investigated, the development law of regional karst fissures was studied, the groundwater was collected and tested through a large-scale collection of groundwater to obtain the change law of chemical characteristics and water quality characteristics of groundwater, and the water quality evaluation was carried out for the regional karst groundwater in this paper. The results show that, the whole area is dominated by carbonate rock distribution areas, and the distribution of water systems is relatively developed. The strata are distributed from the Lower Paleozoic Cambrian to the Cenozoic Quaternary, and contain multiple first-order folds. The regional karst dynamic action is strong, and many tunnels or caves of different scales were shown, which are conducive to the enrichment of groundwater. Karst groundwater is neutral and alkaline water, the water is clear and transparent with good taste, and meets the national drinking water hygiene standards. The content of toxic trace elements and fluoride in the water source is generally lower than the limit value specified by the national standard and the accumulated toxic heavy metals is never found. The overall water quality is of good quality and suitable for the development and utilization of various purposes.

• 동굴
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• 제5권6호
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• pp.31-39
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• 1980

우리나라에는 캠브로-오오도비스(Cambro-Ordovician)기에 속하는 조선누층군의 대석회암통이 넓게 분포되어 있어 석회암지대 특유의 Karst지형을 이루는 곳이 많다. 본 논문의 연구대상지역은 고생대 캠브로-오오도비스기의 조선계 대석회암통에 속하는 옥천지향사의 북부태백산지구를 중심으로 한 석회암 분포지역 중에서 Sinkhole terrain이 비교적 잘 발달되고 해발고도가 상이한 3개 지역을 선정하였다.(중략)

• 동굴
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• 제4호
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• pp.97-100
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• 1996

The American Cave and Karst Center - the name might lead one to believe that this museum is a place for specially - focused, highly technical caverns, and scientists. While the museum will appeal to these individuals, it will by no means exclude anyone else. In fact, this article will demonstrate that the museum is a place for everyone! The following categories will show those who will find something of interest to themselves in the museum(omitted)

• 동굴
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• 제16권17호
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• pp.23-26
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• 1988

석회동굴은 Karst지형 지역에서 지하 형성물로 나타나는 공동지역으로, 이 공동화된 공간에 2차적으로 석순, 석주, 종유석등이 침전되어 생긴 동굴이다. 이런 Karst 지형은 석회암지층에서 용식작용으로 생겨나는데, 우리나라에서는 황해도의 서흥, 신막, 수안, 곡산 물질지역과 평안남도의 덕천, 성천, 강동지방, 그리고 강원도의 삼척, 영월, 평창, 정선, 명주지방, 충청북도의 단양, 제천, 괴산지역 그밖에 경상북도의 울진 지역에도 분포한다.(중략)