確定論的 接近 方法에 貯水地 最適 運營律 導出

김재한,김정엽,정관수 忠南大學校 産業技術硏究所 1998 산업기술연구논문집 Vol.13 No.2

The purpose of this study is to develope deterministic optimal reservoir operation rules by integrating dynamic programming, regression analysis, and simulation. The objective function was designed to minimize system-loss function Z. The time dependent loss function is govemed by release R?? for each month. The general constraints for the given objective function are derived from mass balance, upper and lower bounds of the storages and releases. In this study, regression method was applied for inflow and storage to develop the operation rules. The method was successfully applied to the data from Daechung Dam. Differences between observed and predicted value may be caused by the differences in intake amounts.

Numerical analysis of flow characteristics at the bifurcation channel by changing of discharge ratio using TELEMAC-2D

Jung Daejin,Jang Chang-Lae,Jung Kwansue 한국수자원학회 2019 한국수자원학회논문집 Vol.52 No.1

본 연구에서는 분류부 흐름에 대한 TELEMAC-2D 2차원 수치모형의 적용성을 검증하고, 수치실험을 통한 분류유량비 계산식의 비교분석, 분류유 량비 변화에 따른 분류부 흐름특성 변화를 분석하였다. 본 수치모형은 분류부 수심평균 유속분포와 수위에 대해 실내실험결과와 잘 일치하는 결과를 나타냈다. 주수로의 하류방향 관성력과 모멘트가 감소하면 분류유량비가 증가하게 되고, 분류수로에서 상대적인 고유속 분포구간은 넓어지며, 분류수로 주흐름의 역방향 유속은 감소한다. 분류유량비가 증가할수록 분류수로 내흐름분리구역 규모는 감소하며, 흐름분리구역 규모 산정시 유선분포 작도뿐만 아니라 종방향 프루우드 수가 Fr≈0 이 되는 지점 확인으로 더 명확하게 산정할 수 있다. This study investigates the flow characteristics, such as velocity distributions, size and location of recirculation zone, longitudinal flow change rates, and bifurcation discharge ratio in the bifurcation channel by TELEMAC-2D, a 2D numerical model. The numerical model is validated by previous experimental results and the numerical results are in relatively good agreement with the experimental results, such as the water surface elevation and velocity distribution in the channels. As the inertial force and moment in the main channel decrease, the bifurcation discharge ratio increases, and the relative high velocity distribution becomes wider and the reverse velocity of the main stream decreases in the branch channel. As the bifurcation discharge ratio increases, the size of the recirculation zone in the branch channel decreases and it can be more clearly calculated by determining the point where the longitudinal froude number Fr≈0 as well as drawing the distribution of the streamline distribution.

Biomechanical Characteristics of Three Baseplate Rotational Arrangement Techniques in Total Knee Arthroplasty

Kang, KwanSu,Jang, Young Woong,Yoo, Oui Sik,Jung, Dukyoung,Lee, Sung-Jae,Lee, Myung Chul,Lim, Dohyung Hindawi 2018 BioMed research international Vol.2018 No.-

<P><B>Introduction</B></P><P> Several ongoing studies aim to improve the survival rate following total knee arthroplasty (TKA), which is an effective orthopedic surgical approach for patients with severely painful knee joint diseases. Among the studied strategies, baseplate rotational arrangement techniques for TKA components have been suggested but have been the subject of only simple reliability evaluations. Therefore, this study sought to evaluate comparatively three different baseplate rotational arrangement techniques that are commonly used in a clinical context.</P><P><B> Materials and Methods</B></P><P> Three-dimensional (3D) finite element (FE) models of the proximal tibia with TKA were developed and analyzed considering three baseplate rotational arrangement techniques (anterior cortex line, tibial tuberosity one-third line, and tibial tuberosity end line) for six activities of daily life (ADLs) among patients undergoing TKA. Mechanical tests based on the ASTM F1800 standard to validate the FE models were then performed using a universal testing machine. To evaluate differences in biomechanical characteristics according to baseplate rotational arrangement technique, the strain and peak von Mises stresses (PVMSs) were assessed.</P><P><B> Results</B></P><P> The accuracy of the FE models used in this study was high (94.7 ± 5.6%). For the tibial tuberosity one-third line rotational arrangement technique, strains ≤ 50 <I>µ</I>strain (the critical bone damage strain, which may affect bone remodeling) accounted for approximately 2.2%–11.3% and PVMSs within the bone cement ranged from 19.4 to 29.2 MPa, in ADLs with high loading conditions. For the tibial tuberosity end line rotational arrangement, strains ≤ 50 <I>µ</I>strain accounted for approximately 2.3%–13.3% and PVMSs within the bone cement ranged from 13.5 to 26.7 MPa. For anterior cortex line rotational arrangement techniques, strains ≤50 <I>µ</I>strain accounted for approximately 10.6%–16.6% and PVMSs within the bone cement ranged from 11.6 to 21.7 MPa.</P><P><B> Conclusion</B></P><P> The results show that the most recently developed frontal cortex line rotational alignment technique is the same or better than the other two rotational alignment techniques in terms of biomechanics. This finding can be, however, dependent on the contact characteristics between the baseplate and the proximal tibia. That is, it is indicated that the optimum baseplate rotational arrangement technique in terms of reducing the incidence of TKA mechanical failure can be achieved by adjusting the characteristics of contact between the baseplate and the proximal tibia.</P>

The Local Observed Trends and Variability in Rainfall Indices Over the Past Century of the Yom River Basin, Thailand

Ruetaitip Mama,Kwansue Jung,Butsawan Bidorn,Matharit Namsai,Meiyan Feng 한국방재학회 2018 한국방재학회지 Vol.18 No.4

강우 패턴의 변화는 홍수나 가뭄과 같은 극한 수문 사상 의발생빈도에 직접적으로 영향을 미칠 수 있으며 물 공급이나 홍수관리 등과 관련하여 이해당사자들 간의 분쟁을 초래할 수 있다. 본 연구의 목적은 과거 90년(1921~2015)의 기간을 대상으로 Yom강유역에 대한 강우량의 변동성을 분석하는 것이다. 이를 위하여 13개 수문관측소의 강우 자료를 기반으로 강우와 관련된 다양한 극한 사상들에 대한 장기경향성분석을 Mann-Kendall 방법을 이용하여 신뢰 수준 95%에서 수행하였다. 대상 변수는연 총강수량(PRCPTOT), 연속건조일수(CDD), 연속습윤일수(CWD), 호우일수(R 10 ), 대형호수일수(R 20 ), 일최대강우량 (R max1 ), 5일 최대강우량(R max5 ), 연간총강우일수(R day ) 등이다. 주요한 결과로서 PRCPTOT, R max1 , R max5 는 대상 유역의 서부지역에서 증가추세를 보이는 것으로 나타났다. 또한 CDD지수의 경우 대상유역내 55% 이상의 지역에서 감소추세를 보였다. 한편, CWD는 Yom강유역 하류지역을 제외하고는 유역면적의 약 77%를 차지히여 증가 추세를 보이는 것으로 나타났다. 연간 총강우일수는 대상 유역의 남부지역 약 44%에서 감소 경향을 나타냈다. 그러나 호우와 대형 호우의 경우 Yom강유역 하류지역에서 상당한 증가 추세를 보임을 확인할 수 있었다. 이러한 결과들은 Yom강유역의 서부지역에서 현저한 홍수의 증가 경향을 시사한다. 한편, 대상 유역의 중심부에서는 가뭄의 경향이 증가하는 것으로 나타났다. 따라서 Yom강유역내 강우 패턴의 변화는 향후 해당지역의 수자원계획과 관리를 위하여 반드시 그 영향을 고려하야 할 것이다. A changing rainfall pattern can directly affect the frequency of occurrence of extreme event such as floods and droughts. These extreme events will cause future political conflicts, especially those dealing with water supply and flood management. The purpose of this study is to examine the variability of rainfall in the Yom River basin, Thailand, during the past 90 years (1921-2015). Based on rainfall data from 13 hydrological stations, long-term trends inrainfall and various rainfall-related extreme events, which consist of the annual total precipitation (PRCPTOT), consecutive dry days (CDD), consecutive wet days (CWD), number of heavy rainfall days (R 10 ), number of very heavy rainfall days (R 20 ), daily maximum rainfall (R max1 ), five-day maximum rainfall (R max5 ), and annual total rainy day (R day ) in the Yom River basin, were analyzed using the Mann-Kendall method with 95% confident level. The results suggest that for the PRCPTOT, R max1 , and R max5 indices have experienced a significant increase trend in the western part of basin area. In addition, the decreasing trend was observed over 55% of basin considering for the CDD indices. Meanwhile, the CWD was found an increasing trend approximately 77% of the basin area except in the lower Yom River basin. Result of the annual total rainy day reveal significant decrease trend around 44% of the southern part of the basin. However, the analyses of heavy and very heavy rainfall show a significantly increasing trend at the lower part of the Yom river basin. These results suggest that the trend of flooding has significantly increased along the western part of the Yom River basin. Meanwhile, the tendency of drought events is increasing in middle portion of the basin. The impacts of changes in rainfall pattern in the Yom River basin should be considered in the future water resources planning and management of the country.

도시철도차량 승객하중 데이터측정을 위한 고정밀성 응하중압력 측정시스템 설계 방안 고찰

정구인(Kuin Jung),안청모(Cheongmo Ahn),김영수(Youngsu Kim),김관수(Kwansu Kim),조관현(Kwnahyun Cho),심규원(Gyuwon Shim),지영구(Younggu Ji) 한국철도학회 2014 한국철도학회 학술발표대회논문집 Vol.2014 No.10

본 논문에서는 센서소자와 전자회로를 시스템적으로 모듈화하여 다양한 산업분야에서 가장 폭 넓게 확대되고 있는 스마트센서의 입력신호 처리시스템 제어기능을 활용하여 도시철도차량의 객실별 승객하중 데이터 측정시스템 기술개발에 요구되는 도시철도 환경에 적합한 무선통신기반의 반도체식 압전소자형 압력센서의 성능요구조건과 신호제어를 위한 어플리케이션 설계 및 구축 방안에 대하여 고찰하였다. 도시철도환경에 최적화된 성능과 정밀도 요구사항을 효과적으로 분석하여 전동차 객실 혼잡도 측정시스템 기술개발을 통한 수집된 정보를 기반으로 도시철도 이용자에게 편의성 향상 및 대중교통의 이용효율성 증대에 큰 역할을 할 것으로 기대된다. This paper utilizes the output signal of a systematic modular smart sensor electronics and the sensor element and the most widely expanding in various industries passenger processing system control rooms in the city by rail car load data measurement system technology were investigated for the city railway environment suitable for the required type of semiconductor pressure sensor and a wireless communication based performance requirements for signal control application design and implementation plan. Is expected to increase ease of improed efficiency in the use of public transport to the city railway users and collected through the train room with congestion measurement system based on technolody developed collected optimized for urban railway environment to analyze the performance and accuracy requirements and the large role.

The Local Observed Trends and Variability in Rainfall Indices Over the Past Century of the Yom River Basin, Thailand

Ruetaitip Mama,Kwansue Jung,Butsawan Bidorn,Matharit Namsai,Meiyan Feng 한국방재학회 2018 한국방재학회논문집 Vol.18 No.4

강우 패턴의 변화는 홍수나 가뭄과 같은 극한 수문 사상 의발생빈도에 직접적으로 영향을 미칠 수 있으며 물 공급이나 홍수관리 등과 관련하여 이해당사자들 간의 분쟁을 초래할 수 있다. 본 연구의 목적은 과거 90년(1921~2015)의 기간을 대상으로 Yom강유역에 대한 강우량의 변동성을 분석하는 것이다. 이를 위하여 13개 수문관측소의 강우 자료를 기반으로 강우와 관련된 다양한 극한 사상들에 대한 장기경향성분석을 Mann-Kendall 방법을 이용하여 신뢰 수준 95%에서 수행하였다. 대상 변수는연 총강수량(PRCPTOT), 연속건조일수(CDD), 연속습윤일수(CWD), 호우일수(R 10 ), 대형호수일수(R 20 ), 일최대강우량 (R max1 ), 5일 최대강우량(R max5 ), 연간총강우일수(R day ) 등이다. 주요한 결과로서 PRCPTOT, R max1 , R max5 는 대상 유역의 서부지역에서 증가추세를 보이는 것으로 나타났다. 또한 CDD지수의 경우 대상유역내 55% 이상의 지역에서 감소추세를 보였다. 한편, CWD는 Yom강유역 하류지역을 제외하고는 유역면적의 약 77%를 차지히여 증가 추세를 보이는 것으로 나타났다. 연간 총강우일수는 대상 유역의 남부지역 약 44%에서 감소 경향을 나타냈다. 그러나 호우와 대형 호우의 경우 Yom강유역 하류지역에서 상당한 증가 추세를 보임을 확인할 수 있었다. 이러한 결과들은 Yom강유역의 서부지역에서 현저한 홍수의 증가 경향을 시사한다. 한편, 대상 유역의 중심부에서는 가뭄의 경향이 증가하는 것으로 나타났다. 따라서 Yom강유역내 강우 패턴의 변화는 향후 해당지역의 수자원계획과 관리를 위하여 반드시 그 영향을 고려하야 할 것이다. A changing rainfall pattern can directly affect the frequency of occurrence of extreme event such as floods and droughts. These extreme events will cause future political conflicts, especially those dealing with water supply and flood management. The purpose of this study is to examine the variability of rainfall in the Yom River basin, Thailand, during the past 90 years (1921–2015). Based on rainfall data from 13 hydrological stations, long-term trends inrainfall and various rainfall-related extreme events, which consist of the annual total precipitation (PRCPTOT), consecutive dry days (CDD), consecutive wet days (CWD), number of heavy rainfall days (R 10 ), number of very heavy rainfall days (R 20 ), daily maximum rainfall (R max1 ), five-day maximum rainfall (R max5 ), and annual total rainy day (R day ) in the Yom River basin, were analyzed using the Mann-Kendall method with 95% confident level. The results suggest that for the PRCPTOT, R max1 , and R max5 indices have experienced a significant increase trend in the western part of basin area. In addition, the decreasing trend was observed over 55% of basin considering for the CDD indices. Meanwhile, the CWD was found an increasing trend approximately 77% of the basin area except in the lower Yom River basin. Result of the annual total rainy day reveal significant decrease trend around 44% of the southern part of the basin. However, the analyses of heavy and very heavy rainfall show a significantly increasing trend at the lower part of the Yom river basin. These results suggest that the trend of flooding has significantly increased along the western part of the Yom River basin. Meanwhile, the tendency of drought events is increasing in middle portion of the basin. The impacts of changes in rainfall pattern in the Yom River basin should be considered in the future water resources planning and management of the country.

수리학적 홍수추적에서 운동파 방정식의 파속 산정에 관한 연구

김재한,정관수,서경철 충남대학교 산업기술연구소 1999 산업기술연구논문집 Vol.14 No.2

Celerity is the physical parameter which has the basin characteristics such as channel slope and roughness, and the flow characteristics such as discharge and velocity. Therefore it is very important to determine accurate celerity for the sake of the kinematic wave equation analysis which is widely used as the governing equation of the flood flow. Because celerity changes very fast during the flood period, it is very difficult to observe it. In this study, celerity is estimated analysing the kinematic wave equation of the reach having the gaging station at the both of ends, applied to other event and the result is compared with observed hydrograph. The application is made to Wi-stream experimental basin located at the upstream of the Nakdong river. It has the uniform channel top widths and few tributaries. Analysis of the kinematic wave equation is performed on 6 events during the periods from 1986 to 1992. The estimated average celerity is 0.309, and it include the effects of the baseflow. Calculated hydrograph derived from applying it and observed hydrograph have the high correlation coefficient. This demonstrated that it is possible to derive the ungaged hydrograph out of the analysis of the known hydrograph.

하상변동 예측을 위한 1차원 컴퓨터 모형 개발에 관한 연구

김재한,정관수,장창래 忠南大學校 産業技術硏究所 1998 산업기술연구논문집 Vol.13 No.2

The behavior and characteristics of rivers are highly complex and depend on the numerous environmental changes. Predicting and analyzing the river bed changed in the long term are important to river planning and management. River bed changes have widely influenced river and watershed managements in short and long term. So, many computer models for the channel and sediment flows due to these problems have been developed to predict river characteristics. But these models have required a lot of data and handing works. In this study a simplified mathematical computer model for a generalized river reach is developed to improve these one-dimensional models and predict unmeasured and straightened rivers, and this computer model is compared with one-dimensional model, HEC-6, and quasy-two-dimensional model, GSTARS2.0. The results of this computer model show reasonable agreements with these of HEC-6 and GSTARS2.0

상수관망 해석에서의 모형 구성 및 수요할당에 따른 영향분석에 관한 연구

김성한(Seonghan Kim),정관수(Kwansue Jung),윤석민(Sukmin Yoon),박노석(No-Suk Park) 대한환경공학회 2020 대한환경공학회지 Vol.42 No.3

목적 : 상수관망 모델링에서 불확실성을 줄이기 위해 이제까지 몇몇 모델 방법론들이 제안되어왔다. 그러나 이러한 방법들로 모델을 구성하는 경우 복잡해지고, 데이터 관리가 어려운 단점이 있었다. 이에 본 연구에서는 이를 상충할 수 있는 ‘Hybrid 모형’의 구성을 제안하고자 하였다. 방법 : 모형별 검증을 위하여 먼저 간략화 모델의 비교 기준이 되는 모든 배수관과 급수관이 포함된 모형(원 모형) 과 수도미터의 위치를 고려한 3가지 간략화 모형을 구축하여 모형별로 고정상태 모의(steady-state simulation)와 시간변화 모의(extended period simulation)로 구분하여 관망해석을 수행하고 그 결과에 대해 수량, 수압 및 수질을 대상으로 비교분석하였다. 결과 및 토의 : 그 모델 평가 결과, ‘All-meters Model’과 ‘All-Connections Model’은 관망 내 수질 모사를 위한 관망모델 구축에 있어 정확한 결과를 얻는 것으로 밝혀졌다. 동수두의 차이에 따라 물 흐름 경로가 달라질 수 있는 격자형 관망에서는 실제 수요가 반영된 상세모형(All-meters 또는 All-connections Model)을 구축하고, 간략화되어도 물 흐름 경로가 동일하고 수요할당의 영향이 크지 않는 수지형 관망에서는 간략화된 모형(Street-meters aggregation 또는 Reduced-meters Model)으로 구축하는 혼합형(Hybrid형) 모형구축을 제안한다. 결론 : 각 모형은 고정상태 모의와 시간변화 모의로 나누어 실시한 결과 고정상태모의의 동수두 비교에서는 모든 모형에서 동수두의 차이가 크게 발생하지 않았으나 시간변화 모의의 물 연령 비교에서는 모형별로 상당한 차이를 나타내었다. 최장 시간은 All-meters 모형 66.7시간, All-connections 모형 53.6시간, Street 모형 52.4시간 및 Reduced 모형이 49.4시간으로 나타났다. Objectives : In order to reduce the uncertainty of the pipe network modeling, the model structure was basically included all distribution pipes and several models were proposed according to the location of the water meters. Methods : For models verification, first, a steady state simulation of each model was made by constructing a model including all water supply pipes (All-meters Model), which are the bases of 3 simplified models, and considering the location of all water meters. The network analysis was performed by dividing into the steady state and the extended period simulation. Results and Discussion : From the results of models comparison, ‘All-meters Model’ and ‘All-connections Model’ were found to obtain more accurate results for constructing a water network model for simulation of water quality events in distribution network. When constructing an ‘All-meters Model’ in all networks, the model becomes complicated and data management does difficult. Therefore this study suggests a hybrid model construction. Conclusions : It would be reasonable to construct a detailed model (All-meters or All-connections Model) in looped network in which the water flow path can be changed according to the difference of water head, and a skeletonized model (Street-meters aggregation or Reduced-meters Model) for a branch network that does not have a significant impact on demand allocations.

Sediment Erosion and Transport Experiments in Laboratory using Artificial Rainfall Simulator

Ram Krishna Regmi,Kwansue Jung,Hajime Nakagawa,Jaewon Kang,Giha Lee 한국지반환경공학회 2014 한국지반환경공학회논문집 Vol.15 No.4

Catchments soil erosion, one of the most serious problems in the mountainous environment of the world, consists of a complex phenomenon involving the detachment of individual soil particles from the soil mass and their transport, storage and overland flow of rainfall, and infiltration. Sediment size distribution during erosion processes appear to depend on many factors such as rainfall characteristics, vegetation cover, hydraulic flow, soil properties and slope. This study involved laboratory flume experiments carried out under simulated rainfall in a 3.0 m long × 0.8 m wide × 0.7 m deep flume, set at 17° slope. Five experimental cases, consisting of twelve experiments using three different sediments with two different rainfall conditions, are reported. The experiments consisted of detailed observations of particle size distribution of the out-flow sediment. Sediment water mixture out-flow hydrograph and sediment mass out-flow rate over time, moisture profiles at different points within the soil domain, and seepage outflow were also reported. Moisture profiles, seepage outflow, and movement of overland flow were clearly found to be controlled by water retention function and hydraulic function of the soil. The difference of grain size distribution of original soil bed and the out-flow sediment was found to be insignificant in the cases of uniform sediment used experiments. However, in the cases of non-uniform sediment used experiments the outflow sediment was found to be coarser than the original soil domain. The results indicated that the sediment transport mechanism is the combination of particle segregation, suspension/saltation and rolling along the travel distance.