실측유량 자료를 활용한 홍수량 빈도해석 기법 평가

김태정,김장경,송재현,김진국,권현한,Kim, Tae-Jeong,Kim, Jang-Gyeong,Song, Jae-Hyun,Kim, Jin-Guk,Kwon, Hyun-Han 한국수자원학회 2022 한국수자원학회논문집 Vol.55 No.5

For water resource management, the design flood is calculated using the flood frequency analysis technique and the rainfall runoff model. The method by design flood frequency analysis calculates the stochastic design flood by directly analyzing the actual discharge data and is theoretically evaluated as the most accurate method. Actual discharge data frequency analysis of the measured flow was limited due to data limitations in the existing flood flow analysis. In this study, design flood frequency analysis was performed using the measured flow data stably secured through the water level-discharge relationship curve formula. For the frequency analysis of design flood, the parameters were calculated by applying the bayesian inference, and the uncertainty of flood volume by frequency was quantified. It was confirmed that the result of calculating the design flood was close to that calculated by the rainfall-runoff model by applying long-term rainfall data. It is judged that hydrological analysis can be done from various perspectives by using long-term actual flow data through hydrological survey.

Simple Pulmonary Eosinophilia Evaluated by Means of FDG PET: the Findings of 14 Cases

김태정,Kyung Won Lee,Hyae Young Kim,Joo-Hyuk Lee,Eun-A Kim,Seok Ki Kim,강건욱 대한영상의학회 2005 Korean Journal of Radiology Vol.6 No.4

Objective: We wanted to describe the findings of simple pulmonary eosinophilia with using 18 fluorodeoxyglucose (FDG) positron emission tomography (PET). Materials and Methods: We analysed the findings of 14 patients who underwent thoracic computed tomography (CT) and PET, and then they were subsequently proven to have simple pulmonary eosinophilia. PET studies were performed in four patients with malignancy to evaluate for cancer metastasis, and PET scans were also done in 10 healthy subjects who underwent volunteer cancer screening. The PET scans were evaluated by using the maximum standardized uptake values (SUVs). The subjects' CT findings also were reviewed and correlated with the PET findings. Results: A total of 42 nodules were detected on the CT scans. There were single nodules in three patients and multiple nodules in 11 patients (mean number of nodules: 3, range: 1 10, mean diameter: 9.5 mm 4.7). Twelve of 42 (28.6%) nodules showed FDG uptake and their mean maximum SUV was 2.5 1.6 (range: 0.6 5.3). Five of six solid nodules showed FDG uptake (2.2 1.1, range: 0.9 3.6), six of 11 semisolid nodules showed FDG uptake (3.1 1.8, range: 0.6- 5.3) and one of 25 pure ground-glass opacity nodule showed a maximum SUV of 0.8. The maximum SUVs of seven nodules in five patients were greater than 2.5. The maximum SUVs were significantly different according to the nodule types (p < 0.001). Conclusion: Simple pulmonary eosinophilia commonly causes an increase in FDG uptake. Therefore, correlation of the PET findings with the CT findings or the peripheral eosinophil counts can help physicians arrive at the correct diagnosis of simple pulmonary eosinophilia.

다중 기상모델 앙상블을 활용한 다지점 강우시나리오 상세화 기법 개발

김태정,김기영,권현한,Kim, Tae-Jeong,Kim, Ki-Young,Kwon, Hyun-Han 대한토목학회 2015 대한토목학회논문집 Vol.35 No.2

기후모형으로 가장 널리 사용되는 GCM의 불확실성 및 시공간적 편의로 인하여 GCM으로부터 생산된 기상정보를 응용수문분야에서 직접적으로 이용하기 위해서는 상세화 과정이 필수적으로 요구된다. 본 연구에서는 선행연구에서 개발된 비정상성 은닉 마코프 모형(Non-stationary Hidden Markov Chain Model, NHMM)을 기반으로 다지점 공간상관성을 고려할 수 있는 Chow-Liu Tree 알고리즘과 결합하여 유역단위 강우시나리오 상세화 기법(CLT-NHMM)으로 확장하였으며, 낙동강 유역에 적용하여 적용성을 평가하였다. 상관행렬(correlation matrix)을 통한 강우네트워크의 공간상관성 평가결과 유역상관성이 우수하게 모의하는 것을 확인하였으며, 강수의 빈도 및 양적 관점에서 효과적인 모의가 가능하였다. 본 연구에서 제시한 CLT-NHMM 모형은 수자원뿐만 아니라 수문자료를 입력 자료로 하는 농업, 보건, 환경 및 에너지 등 다양한 응용기상분야에 핵심 기술로 활용이 전망된다. General Circulation Models (GCMs) are the basic tool used for modelling climate. However, the spatio-temporal discrepancy between GCM and observed value, therefore, the models deliver output that are generally required calibration for applied studies. Which is generally done by Multi-Model Ensemble (MME) approach. Stochastic downscaling methods have been used extensively to generate long-term weather sequences from finite observed records. A primary objective of this study is to develop a forecasting scheme which is able to make use of a MME of different GCMs. This study employed a Nonstationary Hidden Markov Chain Model (NHMM) as a main tool for downscaling seasonal ensemble forecasts over 3 month period, providing daily forecasts. Our results showed that the proposed downscaling scheme can provide the skillful forecasts as inputs for hydrologic modeling, which in turn may improve water resources management. An application to the Nakdong watershed in South Korea illustrates how the proposed approach can lead to potentially reliable information for water resources management.

위성정보 빅데이터 활용 국토종합관리 기술개발사업 소개

김태정,Taejung Kim 대한원격탐사학회 2023 大韓遠隔探査學會誌 Vol.39 No.5

A research project titled as Development of Comprehensive Land Management Technology using Satellite Image Information, funded by the Ministry of Land and Transportation, is being conducted to improve the efficiency of land management and to boost satellite image utilization in the private sector. This editorial describes the introduction of the project and papers presented in this special edition.

근 위축성 측삭 경화증 환자 1례 보고

김태정,문아지,이성근,이기상,Kim, Tae-jung,Moon, A-ji,Lee, Seoung-geun,Lee, Key-sang 대한중풍순환신경학회 2012 대한중풍.순환신경학회지 Vol.13 No.1

Amyotrophic lateral sclerosis(ALS) is a progressive disorder that causes degeneration of motor neurons of the brain and spinal cord. It is characterized by loss of motor neurons leading to muscle weakness, and sensation and mental function stay intact during the course of the disease. Diagnostic tests include magnetic response imaging(MRI), electromyogram(EMG), muscle biopsy, and blood tests. In order to a definitive diagnosis of ALS, damage must be evident in both upper and lower motor neurons. When three limbs are sufficiently affected, the diagnosis is ALS. There is no cure for ALS. We experienced one case of ALS, the patients was diagnosed as ALS by EMG and symptoms. We diagnosed her as ShinEumHur(SEH) and treated by Choakwiyeum(左歸飮). We report the change of her symptoms through oriental medical treatment.

강우모의기법과 강우-유출 모형을 연계한 댐 유입량 자료 생성기법 개발

김태정,소병진,유민석,권현한,Kim, Tae-Jeong,So, Byung-Jin,Ryou, Min-Suk,Kwon, Hyun-Han 한국수자원학회 2016 한국수자원학회논문집 Vol.49 No.4

일반적으로 하천의 유량은 댐과 같은 수공구조물에 의해 조정된 유량으로 수자원계획을 위해서 필요한 자연유량과는 차이가 크다. 수자원계획을 수립함에 있어 자연 유입량 정보는 댐 운영과 수문분석을 위한 필수적인 정보이다. 본 연구에서는 댐 유역 일유입량 모의기법을 위한 통합 모형을 개발하였다. 첫째, 장기 강우-유출 모형의 입력강우자료로 사용하기 위하여 평균 및 중앙값과 같은 통계적 모멘트를 효과적으로 재현하고 극치 강우량 재현에 유리한 불연속 Kernel-Pareto 확률분포 기반의 강우모의기법을 통하여 강우모의를 수행하였다. 둘째, SAC-SMA 장기 강우-유출 모형의 매개변수를 Bayesian MCMC 기법을 통하여 최적화하여 산정된 매개변수의 사후분포를 활용하여 댐 유입량 시나리오 도출하였다. 댐 유역을 대상으로 개발된 모형을 평가한 결과 자연유량과 통계적으로 유사한 특성을 가지는 시나리오를 생성할 수 있었으며, 물수지 분석 등과 같은 수자원계획을 위한 시나리오로 활용이 가능할 것으로 판단된다. Generally, a natural river discharge is highly regulated by the hydraulic structures, and the regulated flow is substantially different from natural inflow characteristics for the use of water resources planning. The natural inflow data are necessarily required for hydrologic analysis and water resources planning. This study aimed to develop an integrated model for more reliable simulation of daily dam inflow. First, a piecewise Kernel-Pareto distribution was used for rainfall simulation model, which can more effectively reproduce the low order moments (e.g. mean and median) as well as the extremes. Second, a Bayesian Markov Chain Monte Carlo scheme was applied for the SAC-SMA rainfall-runoff model that is able to quantitatively assess uncertainties associated with model parameters. It was confirmed that the proposed modeling scheme is capable of reproducing the underlying statistical properties of discharge, and can be further used to provide a set of plausible scenarios for water budget analysis in water resources planning.

수공학 분야의 레이더 강수자료 활용전망 및 시사점

김태정,김장경,권현한,Kim, Tae-Jeong,Kim, Jang-Gyeong,Gwon, Hyeon-Han 한국수자원학회 2018 물과 미래(한국수자원학회지) Vol.51 No.3

초단기 강우예측을 위한 기상레이더 강우장 추적기법 개발

김태정,이동률,권현한,Kim, Tae-Jeong,Lee, Dong-Ryul,Kwon, Hyun-Han 한국수자원학회 2015 한국수자원학회논문집 Vol.48 No.12

초단기 홍수예보를 위한 주요자료로서 최근 기상레이더의 중요성이 크게 부각되고 있다. 기상레이더는 넓은 지역에 걸쳐 실시간으로 강우현상 감시가 가능하며 지상우량계로는 파악이 불가능한 미계측유역을 통과하는 강우장의 이동 및 변화 파악이 가능한 장점이 있다. 본 연구는 강우장의 공간적 분포와 레이더 강우세포를 추적하는 강우장 예측 해석방안을 수립하였다. 이를 위해 강우장의 공간적인 이동을 고려하기 위해 강우장의 바람장 이류(advection) 패턴을 추출하여 각 강우세포가 가지는 이동방향 및 속도를 고려한 강우장 추적기법을 통하여 강우장을 예측하였다. 본 연구를 통하여 개발된 기상레이더 강우장 상관분석 기법을 활용한 초단기강우예측 결과는 집중호우시 홍수 예 경보를 위한 수문모형의 입력자료로 활용이 가능할 것으로 사료된다. Weather radar rainfall data has been recognized for making valuable contributions to short-term flood forecasting and management over the past decades. There are several advantages to better monitoring rainfall in ungauged area compared to ground-based rain gauges with which spatial patterns of the rainfall are not effectively identified. Hence, this study aims to develop a new scheme to forecast spatio-temporal rainfall field. The proposed model was based on an advection scheme to track wind patterns and velocity. The results showd a promising forecasting skill with quantitative and qualitative measures. It was confirmed that the forecasted rainfall may be effectively used an input data for a distributed hydrological model.

KOMPSAT-2 영상 PAN밴드의 내부표정 정확도 분석 및 개선방안 연구

김태정,정재훈,김덕인,Kim, Tae-Jung,Jeong, Jae-Hoon,Kim, Deok-In 대한원격탐사학회 2010 大韓遠隔探査學會誌 Vol.26 No.4

이 논문에서는 KOMPSAT-2 스테레오 영상의 PAN밴드에 존재하는 미세한 크기의 Y시차가 발생하는 원인을 규명하고 이를 개선하기 위한 일련의 실험 및 분석과정을 보고한다. 분석결과, Y시차가 발생하는 원인이 KOMPSAT-2 영상을 생성할 때 PAN밴드를 MS밴드와 일치하도록 Warping처리하는 과정에서 발생한 Resampling 오차 때문인 것으로 판단할 수 있었다. 또한 엄밀한 PAN밴드의 Warping 방식을 적용하여 Resampling 오차를 제거함으로써 Y 시차문제가 상당부분 개선될 수 있음을 확인하였다. 또한 KOMPSAT-2 영상 PAN밴드에서 관측된 밝기값 밀림현상도 엄밀한 Warping처리를 통해서 개선될 수 있음을 확인하였다. 따라서, 보다 엄밀한 Warping기법이 KOMPSAT-2 영상처리과정에 적용될 수 있다면 KOMPSAT-2 영상의 기하정확도 및 복사정확도가 많이 개선될 수 있을 것으로 기대한다. This paper reports experiments and analysis work done to find out the cause of Y parallex for stereo pairs of KOMPSAT-2 images and means to improve the Y parallex problem. We could conclude that the Y parallex problem was caused by resampling errors of KOMPSAT-2 PANchromatic bands, induced by the process of warping PANchromatic band with reference to multispectral bands. We could also conclude that a rigorous warping process could improve resampling of KOMPSAT-2 PANchromatic band and remove the Y parallex problem significantly. We also confirmed that a rigorous warping process could also remove blocky brightness patterns present on KOMPSAT-2 PANchromatic band. Therefore, by implementing more rigorous warping process within KOMPSAT-2 scene generation procedures, KOMPSAT-2 geometric and radiometric quality will be improved.

비정상성 강우모의기법을 이용한 가뭄 예측기법 개발

김태정,박종현,장석환,권현한,Kim, Tae-Jeong,Park, Jong-Hyeon,Jang, Seok-Hwan,Kwon, Hyun-Han 한국농공학회 2016 한국농공학회논문집 Vol.58 No.5

Drought is a slow-varying natural hazard that is characterized by various factors such that reliable drought forecasting along with uncertainties estimation has been a major issue. In this study, we proposed a stochastic simulation technique based scheme for providing a set of drought scenarios. More specifically, this study utilized a nonstationary Hidden markov model that allows us to include predictors such as climate state variables and global climate model's outputs. The simulated rainfall scenarios were then used to generate the well-known meteorological drought indices such as SPI, PDSI and PN for the three dam watersheds in South Korea. It was found that the proposed modeling scheme showed a capability of effectively reproducing key statistics of the observed rainfall. In addition, the simulated drought indices were generally well correlated with that of the observed.