Publications (7)3.59 Total impact
-
Article: Implementation of a topographically controlled runoff scheme for land surface parameterizations in regional climate models
[show abstract] [hide abstract]
ABSTRACT: The Common Land Model (CLM), the land component of the Community Climate System Model (CCSM), for simulating water and energy exchanges between land and atmosphere has water and energy biases resulting from deficiencies in some parameterizations related to hydrological processes. This paper presents the implementation of modified parameterizations in the terrestrial hydrological scheme of the CLM and their effects on the runoff prediction. In particular, the new formulation for topographically controlled baseflow developed in this study can represent effects of the surface macropores and the vertical change of hydraulic conductivity on baseflow. To assess the performance of the new improved parameterizations, we compare runoff results from a set of offline simulations using the consistent North American Regional Reanalysis (NARR) meteorological forcing dataset and realistic Surface Boundary Conditions (SBCs) with observations from the U.S. Geological Survey (USGS) gauge station for a study catchment around the Ohio Valley region. The new modified scheme especially incorporating topographically controlled baseflow plays a significant role in generating and partitioning surface runoff and subsurface runoff. It is also observed that the new model-simulated subsurface runoff makes a significant contribution to improve the runoff predictability in simulating declining recession curves due to the role of baseflow. Keywordsland surface model–terrestrial hygrologic scheme–topographic control–baseflow–runoffKSCE Journal of Civil Engineering 04/2012; 15(7):1309-1318. · 0.38 Impact Factor -
Article: Estimation of the relative severity of floods in small ungauged catchments for preliminary observations on flash flood preparedness: a case study in Korea.
[show abstract] [hide abstract]
ABSTRACT: An increase in the occurrence of sudden local flooding of great volume and short duration has caused significant danger and loss of life and property in Korea as well as many other parts of the World. Since such floods usually accompanied by rapid runoff and debris flow rise quite quickly with little or no advance warning to prevent flood damage, this study presents a new flash flood indexing methodology to promptly provide preliminary observations regarding emergency preparedness and response to flash flood disasters in small ungauged catchments. Flood runoff hydrographs are generated from a rainfall-runoff model for the annual maximum rainfall series of long-term observed data in the two selected small ungauged catchments. The relative flood severity factors quantifying characteristics of flood runoff hydrographs are standardized by the highest recorded maximum value, and then averaged to obtain the flash flood index only for flash flood events in each study catchment. It is expected that the regression equations between the proposed flash flood index and rainfall characteristics can provide the basis database of the preliminary information for forecasting the local flood severity in order to facilitate flash flood preparedness in small ungauged catchments.International Journal of Environmental Research and Public Health 04/2012; 9(4):1507-22. · 1.61 Impact Factor -
Article: Assessment of vulnerability to extreme flash floods in design storms.
[show abstract] [hide abstract]
ABSTRACT: There has been an increase in the occurrence of sudden local flooding of great volume and short duration caused by heavy or excessive rainfall intensity over a small area, which presents the greatest potential danger threat to the natural environment, human life, public health and property, etc. Such flash floods have rapid runoff and debris flow that rises quickly with little or no advance warning to prevent flood damage. This study develops a flash flood index through the average of the same scale relative severity factors quantifying characteristics of hydrographs generated from a rainfall-runoff model for the long-term observed rainfall data in a small ungauged study basin, and presents regression equations between rainfall characteristics and the flash flood index. The aim of this study is to develop flash flood index-duration-frequency relation curves by combining the rainfall intensity-duration-frequency relation and the flash flood index from probability rainfall data in order to evaluate vulnerability to extreme flash floods in design storms. This study is an initial effort to quantify the flash flood severity of design storms for both existing and planned flood control facilities to cope with residual flood risks due to extreme flash floods that have ocurred frequently in recent years.International Journal of Environmental Research and Public Health 07/2011; 8(7):2907-22. · 1.61 Impact Factor -
Conference Proceeding: Nonlinear indirect adaptive control of a quarter car active suspension
[show abstract] [hide abstract]
ABSTRACT: In this paper, an indirect adaptive controller is applied to the vehicle active suspension with a hydraulic actuator. The inner loop controller, which is a nonlinear adaptive controller, is designed to control the force generated by the nonlinear hydraulic actuator. The spool valve dynamics of the hydraulic actuator is reduced using a singular perturbation technique. The parameter estimation error used in an indirect adaptation is decreased asymptotically. The absolute velocity of a sprung mass is damped down by its negatively proportional term (sky-hook damper) adopted as an outer loop controllerControl Applications, 1996., Proceedings of the 1996 IEEE International Conference on; 10/1996 -
Conference Proceeding: Design and implementation of robust adaptive controller for direct drive manipulators
[show abstract] [hide abstract]
ABSTRACT: In this paper, we consider a dynamics of actuator driving system as well as actuator itself to design a robust adaptive controller for robot manipulators. We propose an adaptation law to guarantee the boundedness of parameter estimates irrespective of the boundedness of other closed-loop signals without data normalization. We also propose a control law to ensure the uniform stability of the closed-loop system without a priori knowledge of the unmodeled dynamics. We show that the tracking error belongs to the normalized error bound, and also show the robustness of the proposed adaptive controller by using an experiment referred to a two-link direct drive manipulatorIndustrial Electronics, Control and Instrumentation, 1994. IECON '94., 20th International Conference on; 10/1994 -
Conference Proceeding: Real-time simulation for continuous processing of an electrolytictinning line
[show abstract] [hide abstract]
ABSTRACT: In this paper, a real-time simulation is performed to insure the continuous processing of an electrolytic tinning line (ETL). An ETL is modelled mathematically and a simple type of tension and speed controllers are designed to control the tension and speed of the strip to be within the tolerance error bound. The designed controller is implemented and tested by using a real-time simulation system which consists of 32 bit VME-based single board computers and a real-time operating system (VRTX)Industrial Electronics, Control, and Instrumentation, 1993. Proceedings of the IECON '93., International Conference on; 12/1993 -
Article: Real-time simulation for continuous processing of an electrolytic tinning line
[show abstract] [hide abstract]
ABSTRACT: In this paper, a real-time simulation is performed to insure the continuous processing of an electrolytic tinning line (ETL). An ETL is modelled mathematically and a simple type of tension and speed controllers are designed to control the tension and speed of the strip to be within the tolerance error bound. The designed controller is implemented and tested by using a real-time simulation system which consists of 32 bit VME-based single board computers and a real-time operating system (VRTX)Construction and Building Materials - CONSTR BUILD MATER. 01/1993;
Top co-authors
Top Journals
Institutions
-
2011–2012
-
Sun Moon University
Asan, South Chungcheong, South Korea
-
-
1996
-
Samsung Advanced Institute of Technology
Osan, Gyeonggi, South Korea
-
-
1993–1994
-
Korea Institute of Science and Technology
Seoul, Seoul, South Korea
-
