• 화약ㆍ발파
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• 제10권3호
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• pp.8-25
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• 1992

On the Sub- way Construction It is important to Survey in advance the Geological Structure and also to make the Engineering Geological map this paper deseribs the feature of Geological structure of Seoul Area and analyses the recently occured Rock falling acciudents. NATM Tunnelling always must be done with careful observation and measurement of the geological condition.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.1275-1277
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• 2003

This paper presents a geological remote sensing information extraction system, the aim of which is to provide practical models and powerful tools to extract geological information from remote sensing images for geological exploration applications. After reviewing and analyzing the existing methods for geological information extraction, we developed more than ten models to enhance and extract geological information, such as alteration information, linear features and special lithological characters. The system is developed based on Erdas Imagine using its programming language. It has been successfully used in the 'reat Investigation of Land and Natural Resources of China' program.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.1442-1444
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• 2003

This paper presents a geological remote sensing information extraction system, the aim of which is to provide practical models and powerful tools to extract geological information from remote sensing images for geological exploration applications. After reviewing and analyzing the existing methods for geological information extraction, we developed more than ten models to enhance and extract geological information, such as alteration information, linear features and special lithological characters. The system is developed based on Erdas Imagine using its programming language. It has been successfully used in the ‘Great Investigation of Land and Natural Resources of China’ program.

• Geomechanics and Engineering
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• 제25권1호
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• pp.1-16
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• 2021

Machine learning models have been widely used for landslide susceptibility assessment (LSA) in recent years. The large number of inputs or conditioning factors for these models, however, can reduce the computation efficiency and increase the difficulty in collecting data. Feature selection is a good tool to address this problem by selecting the most important features among all factors to reduce the size of the input variables. However, two important questions need to be solved: (1) how do feature selection methods affect the performance of machine learning models? and (2) which feature selection method is the most suitable for a given machine learning model? This paper aims to address these two questions by comparing the predictive performance of 13 feature selection-based machine learning (FS-ML) models and 5 ordinary machine learning models on LSA. First, five commonly used machine learning models (i.e., logistic regression, support vector machine, artificial neural network, Gaussian process and random forest) and six typical feature selection methods in the literature are adopted to constitute the proposed models. Then, fifteen conditioning factors are chosen as input variables and 1,017 landslides are used as recorded data. Next, feature selection methods are used to obtain the importance of the conditioning factors to create feature subsets, based on which 13 FS-ML models are constructed. For each of the machine learning models, a best optimized FS-ML model is selected according to the area under curve value. Finally, five optimal FS-ML models are obtained and applied to the LSA of the studied area. The predictive abilities of the FS-ML models on LSA are verified and compared through the receive operating characteristic curve and statistical indicators such as sensitivity, specificity and accuracy. The results showed that different feature selection methods have different effects on the performance of LSA machine learning models. FS-ML models generally outperform the ordinary machine learning models. The best FS-ML model is the recursive feature elimination (RFE) optimized RF, and RFE is an optimal method for feature selection.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 INTERNATIONAL SYMPOSIUM ON SOIL & GROUNDWATER ENVIRONMENT
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• pp.31-33
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• 2005

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 암반역학위원회 학술세미나 논문집
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• pp.103-114
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• 2002

Stability of cut-slope is considered to have a deep relationship with rock types since rock has its own engineering and geological characteristic such as shear strength, durability, weathering profile, geological structures. Therefore, analysis of geological and engineering characterisics of rock mass is essential for the evaluation of rock slope stability This paper introduces the statistical data of slope failure cases which was collected from highway slopes constructed in sedimentary rock mainly of shale in Ky ng-sang Basin. Primary failure feature in this area is planar failure along the bedding regardless of slope geometry. Even a disasterous slope failure case due to the thick clay layer between the beddings was reported. Failures and rock fall were reported to ocurred frequently after the completion of cutting due to the weathering, so long-term slope stability should be considered as a important factors in design.

• 한국제4기학회지
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• 제21권2호
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• pp.69-73
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• 2007

Inorganic geochemical and mineralogical analyses from the trench sediments of the Hwayang wetland were carried out to verify the wet/dry conditions during 6000 - 5000 yr BP and abnormal event of 6300 yr BP of Korean west coast. Lithostratigraphy, mineralogy and major element concentrations of the sediments of the trench indicate that during 6000 - 5000 yr BP, a wet/dry conditions might be repeated at an interval of 200 years. Carbonate minerals precipitated with the decrease of water depth in the lake or wetland after about 6000 yr BP. On the other hand, the sediments coarser in mean grain size and larger in standard deviation were corresponded with periods of 6300 yr BP and 6230 yr BP. Especially, such a feature of grain size distribution of 6300 yr BP appears in other wetlands situated in the west coast, e.g., Hwangsan wetland and Cheollipo coastal wetland. During the period, the coarse sediments seem to have been delivered by a high energy like storming.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2005년도 Proceedings of The 6th korea-china joint workshop on nuclear waste management
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• pp.236-244
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• 2005

Radioactive wastes arising from a wide range of human activities are in many different physical and chemical forms, contaminated with varying radioactivity. Their common feature is the potential hazard associated with their radioactivity and the need to manage them in such a way as to protect the human environment. The geological disposal is regarded as the most reasonable and effective way to safely disposal high-level radioactive wastes in the world. The conceptual model of geological disposal in China is based on a multi-barrier system that combines an isolating geological environment with an engineered barrier system. The buffer is one of the main engineered barriers for HLW repository. The buffer material is expected to maintain its low water permeability, self-sealing property, radio nuclides adsorption and retardation property, thermal conductivity, chemical buffering property, overpack supporting property, stress buffering property over a long period of time. Benotite is selected as the main content of buffer material that can satisfy above. GMZ deposit is selected as the candidate supplier for Chinese buffer material of High Level Radioactive waste repository. This paper presents geological features of GMZ deposit and basic property of GMZ Na bentonite. GMZ bentonite deposit is a super large scale deposits with high content of Montmorillonite (about $75\%$) and GMZ-l, which is Na-bentonite produced from GMZ deposit is selected as reference material for Chinese buffer material study.

• 자원환경지질
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• 제56권5호
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• pp.533-545
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• 2023

본 연구에서는 고준위 방사성 폐기물 심지층 처분장을 구성하고 있는 천연방벽의 장기안전성에 영향을 줄 수 있는 요소(Feature), 사건(Event), 및 공정(Process)에 대한 조사를 수행하여 FEP 목록을 작성하였다. FEP 목록 작성을 위해 NEA (Nuclear Energy Agency)의 IFEP 목록 3.0이 기초 자료로 활용되었으며, 국외 선도국에서 수행된 지질 조사 및 연구 결과들이 추가적으로 참고되었다. 천연방벽의 성능과 관련하여 총 49개의 FEP 목록이 작성되었으며, 각 인자에 대한 정의, FEP 분류, 장기 안전성에 미치는 영향, 국내 여건에서의 중요도, 정량화 가능 여부 측면에서의 결과가 작성되었다. 또한, 작성된 FEP 목록을 기반으로 처분시설의 장기 안전성에 위협이 될 수 있는 총 3가지의 시나리오를 개발하고 각 시나리오에 있어 천연방벽의 처분 성능에 영향을 주는 지질학적 인자들을 선별 및 관계를 가시화하였다. 본 연구를 통해 구축된 FEP 목록과 시나리오별 인자간 상호관계 가시화 결과는 심지층 처분장의 장기 안전성을 정량 평가하기 위한 수학적 모델 개발에 있어 필수적으로 고려해야 할 인자를 선별 및 구성하는데 중요한 기초 정보를 제공할 수 있을 것으로 판단되며, 방폐물 처분장 부지확정을 위한 천연방벽의 주요 성능과 관련된 기준안을 마련하는 데 유용하게 활용될 수 있을 것으로 보인다.

• 한국컴퓨터정보학회논문지
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• 제12권4호
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• pp.229-237
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• 2007

대용량의 지리정보시스템에 저장된 자료에 대한 접근과 관리에 대한 복잡성을 해결하기 위하여 공간 자료와 비공간 자료에 대한 물리적이고 개념적인 사항들을 메타데이터로 구축하고 활용할 필요가 있다. 이에 따라 공간개체의 공간적 요소와 비공간적 요소를 함께 관리하는 지하수 관리시스템에서도 공간 개체에 대한 메타데이터의 구축이 필요하며 이러한 메타데이터 구축 시 개체수준의 메타데이터를 구축해야 한다. 따라서 이 논문에서는 DXF 포맷 중심의 Tile-based 지형도에 입력한 지하수의 메타정보를 개체기반 지하수관리시스템을 위한 메타데이터의 모델을 제시한다. 또한 메타데이터 모델에서 개체 수준과 자료집합 수준에서 메타데이터를 모델링하고 지하수관리시스템을 위한 메타데이터의 표준 명세를 제시한다.