• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.237-240
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• 2004

In this study, the digital image processing with image enhancement based on homomorphic filtering was performed using geophysical imaging data such as gravity, magnetic data and sub-scenes of satellite images such as LANDSAT, IKONOS, and KOMPSAT. Windows application program for executing homomorphic filtering was designed and newly implemented. In general, homomorphic filtering is technique that is based on Fourier transform, which enhances the contrast of image by removing the low frequencies and amplifying the high frequencies in frequency domain. We can enhance the image selectively using homomorphic filtering as compared with the existing method, which enhance the image totally. Through several experiment using remotely sensed imagery and geophysical image with this program, it is concluded that homomorphic filtering is more effective to reveal distinct characteristics for some complicated and multi-associated features on image data.

• Journal of Information Processing Systems
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• 제19권4호
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• pp.554-562
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• 2023

This research offers a sports video action recognition approach based on the fish swarm algorithm in light of the low accuracy of existing sports video action recognition methods. A modified fish swarm algorithm is proposed to construct invariant features and decrease the dimension of features. Based on this algorithm, local features and global features can be classified. The experimental findings on the typical sports action data set demonstrate that the key details of sports action can be successfully retained by the dimensionality-reduced fusion invariant characteristics. According to this research, the average recognition time of the proposed method for walking, running, squatting, sitting, and bending is less than 326 seconds, and the average recognition rate is higher than 94%. This proves that this method can significantly improve the performance and efficiency of online sports video motion recognition.

• 한국지구과학회지
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• 제32권1호
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• pp.57-72
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• 2011

이 연구의 목적은 한국지질자원연구원에서 실시한 지식재산 교육기부의 효과를 연수 참여 교사들의 인식을 통해 알아보는 것이다. 한국지질자원연구원은 Creative Geo Educamp-"지질과학자와 함께 하는 테마여행"이라는 주제로 2010년 7월 6일부터 8일까지 중등교원 35명, 7월 20일부터 22일까지 초등 교원 31명을 대상으로 합숙 연수를 실시하였다. 이번 연수의 목적은 한국지질자원연구원이 축적해온 지식재산을 활용하여 공교육 강화에 기여하고자 한 것이다. 이를 위해, 연수과정에서 2009 개정 교육과정의 창의적 체험활동 지도 교재와 kit를 개발 보급하였다. 설문 결과, 교사들은 교재와 kit는 창의적 체험활동 지도에 적절한지에 대해 중등 교원이 4.49, 초등 교원이 4.80으로 응답하여 높은 타당성을 나타냈고 향후 지질분야 창의적 체험활동 지도에 도움이 될 것으로 확인되었다.

• 한국지형학회지
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• 제28권2호
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• pp.31-44
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• 2021

Due to recent climate change, continuous soil loss is occurring in the mountainous watershed. The development of geographic information systems allows the spatial simulation of soil loss through hydrological models, but more researches applied to the mountain watershed areas in Korea are needed. In this study, prior to simulating the soil loss characteristics of the mountainous watershed, the field monitoring and the SWAT and GeoWEPP models were used to simulate and analyze the rainfall and runoff characteristics in the mountainous watershed area of Jirisan National Park. As a result of monitoring, runoff showed a characteristic of a rapid response as rainfall increased and decreased. In the simulation runoff results of calibrated SWAT models, R², RMSE and NSE was 0.95, 0.03, and 0.95, respectively. The runoff simulation results of the GeoWEPP model were evaluated as 0.89, 0.30, and 0.83 for R², RMSE, and NSE, respectively. These results, therefore, imply that the runoff simulated through SWAT and GeoWEPP models can be used to simulate soil loss. However, the results of the two models differ from the parameters and base flow of actual main channel, and further consideration is required to increase the model's accuracy.

• Geosciences Journal
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• 제22권6호
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• pp.1053-1067
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• 2018

This paper uses a probability-based approach to study the spatial relationships between landslides and their causative factors in the Mingchukur area, Bostanlik districts of Tashkent, Uzbekistan. The approach is based on digital databases and incorporates methods including probability analysis, spatial pattern analysis, and interactive mapping. First, an object-oriented conceptual model for describing landslide events is proposed, and a combined database of landslides and environmental factors is constructed by integrating various databases within a unifying conceptual framework. The frequency ratio probability model and landslide occurrence data are linked for interactive, spatial evaluation of the relationships between landslides and their causative factors. In total, 15 factors were analyzed, divided into topography, hydrology, and geology categories. All analyzed factors were also divided into numerical and categorical types. Numerical factors are continuous and were evaluated according to their $R^2$ values. A landslide susceptibility map was constructed based on conditioning factors and landslide occurrence data using the frequency ratio model. Finally, the map was validated and the accuracy showed the satisfactory value of 83.3%.

• 대한기계학회논문집 C: 기술과 교육
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• 제1권1호
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• pp.33-38
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• 2013

해상에서의 시추작업은 해저면을 통해서 시추되는 유정에서 이루어지는 일련의 기계적 프로세스라 할 수 있다. 해양 시추설비는 해저에 매장된 석유나 가스의 매장량 확인을 위한 테스트 유정(well)과 이를 경제성 있는 생산용 유정으로 만들기 위해 사용되는 시설로 해양에서의 시추작업은 대부분 타 지역으로의 이동을 위해 이동식으로 제작되며, 작업 해역의 수심에 따라 크게 리그(jack-up, semi-submersible)와 드릴십(drillship)으로 구분할 수 있다. 최근에는 석유와 가스의 개발을 위한 시추작업이 급진적으로 심해로 옮겨가고 있으며 작업 가능 수심이 3,000 m에 이르고 있다. 본 논문에서는 이러한 해상 시추설비에 탑재되는 대표적 해양플랜트 기자재인 시추시스템을 소개하고 최근의 기술개발 동향을 알아보고자 한다.

• 지구물리와물리탐사
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• 제10권1호
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• pp.44-49
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• 2007

고해상도를 가지는 지하 밀도 영상을 얻기 위한 3 차원 중력 역산은 모델 변수들이 급격하게 많아지는 문제가 발생한다. 이 논문에서는 모델 변수들의 수를 줄이기 위해서 오일러 디컨벌루션의 해를 사전정보로 활용하는 3 차원 중력역산을 제안하였다. 이 논문에서 고안한 역산 알고리즘의 핵심은 오일러 디컨벌루션의 해가 얻어진 주위로 역산 공간을 제한하여 역산 해의 비유일성을 줄인 점이다. 먼저 중력 자료에 대한 3 차원 오일러 디컨별루션의 해를 구하고, 오일러 디컨벌루션의 해가 나타나는 주위에서만 3 차원 확장 탐색 역산을 수행하여 지하 밀도 영상을 구하였다. 이 3 차원 중력 역산 방법은 합성 모델에 적용하여 그 성능을 검증하였고, 석회암 지대에 존재하는 공동의 분포를 밝히기 위한 고정밀 중력탐사 자료 역산에도 적용하였다. 결과적으로, 오일러 디컨벌루션의 해를 사전정보로 이용한 역산을 이용하여 분해능이 향상된 고해상도의 지하 멸도 영상을 구할 수 있었다.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제4권4호
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• pp.159-176
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• 2023

The conservation of the raccoon dog (Nyctereutes procyonoides) in South Korea requires the protection and preservation of natural habitats while additionally ensuring coexistence with human activities. Applying habitat map modeling techniques provides information regarding the distributional patterns of raccoon dogs and assists in the development of future conservation strategies. The purpose of this study is to generate potential habitat distribution maps for the raccoon dog in South Korea using geospatial technology-based models. These models include the frequency ratio (FR) as a bivariate statistical approach, the group method of data handling (GMDH) as a machine learning algorithm, and convolutional neural network (CNN) and long short-term memory (LSTM) as deep learning algorithms. Moreover, the imperialist competitive algorithm (ICA) is used to fine-tune the hyperparameters of the machine learning and deep learning models. Moreover, there are 14 habitat characteristics used for developing the models: elevation, slope, valley depth, topographic wetness index, terrain roughness index, slope height, surface area, slope length and steepness factor (LS factor), normalized difference vegetation index, normalized difference water index, distance to drainage, distance to roads, drainage density, and morphometric features. The accuracy of prediction is evaluated using the area under the receiver operating characteristic curve. The results indicate comparable performances of all models. However, the CNN demonstrates superior capacity for prediction, achieving accuracies of 76.3% and 75.7% for the training and validation processes, respectively. The maps of potential habitat distribution are generated for five different levels of potentiality: very low, low, moderate, high, and very high.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2005년도 공동학술대회 논문집
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• pp.197-202
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• 2005

최근 제주도에서 실시된 자기지전류(Magnetotelluric) 탐사 자료에서 일본의 Kii 반도 남동쪽 해상에서 발생한 지진활동과 관련된 전자기 현상이 관측되었으며, 이러한 동지진 전자기장 신호의 특성과 메카니즘을 분석하였다. 전파속도, 파워 스펙트럼의 특성, 지진 기록과의 비교, MT 임피던스의 변화, 타원분극 방향 등의 분석으로부터 전자기장 변동이 지진파 전파 과정에서 측점 주변에서 유도된 전자기장으로 판단되며, 측점 주변의 지전기 및 수리지질학적 구조에 의해 전자기장 변동이 크게 좌우됨을 알 수 있다. 전기역학적 효과의 간단한 고찰을 통해 관측된 전자기장의 크기가 이론적 근사와 유사함을 알 수 있었으며 전자기장의 파워가 가속도 파워와 밀접히 관련되어있음을 알 수 있으나 측점에 따라 전자기장의 크기와 방향이 크게 차이가 나는 것은 설명하기 위해서는 전기역학적 메카니즘 이외의 효과를 고려할 필요가 있다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권5호
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• pp.34-40
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• 2015

It is reported that the intensity of rainfall will likely increase, on average, over the world on 2000. For water resources security, many studies for flow paths from rainfall or snowmelt to subsurface have been conducted. In Korea, few isotopic studies for characterizations of flow path have been undertaken. For a better understanding of how water derived from atmosphere moves to subsurface and from subsurface to stream, an analysis of precipitation and stream water using oxygen-18 and deuterium isotopes in a small watershed, Dorim-cheon, Seoul, was conducted with high resolution data. Variations of oxygen-18 in precipitation greater than 10‰ (δ¹⁸O_max = −1.21‰, δ¹⁸O_min = −11.23) were observed. Isotopic compositions of old water (groundwater) assumed as the stream water collected in advance were −8.98‰ and −61.85‰ for oxygen and hydrogen, respectively. Using a two-component mixing model, hydrograph separation of the stream water in Dorim-cheon was conducted based on weighted mean value of δ¹⁸O. As a result, except of instant dominance of rainfall, contribution of old water was dominant during the study period. On average, 71.3% of the old water and 28.7% of rainfall contributed to the stream water. The results show that even in the small watershed, which is covered with thin soil layer in granite mountain region, the stream water is considerably influenced by old water inflow rather than rainfall.