Jong Min Lee

Publications

3 Optimal Maintenance and Improvement Policies in Water Distribution System: Markov Decision Process Approach

Authors: Go Bong Choi, Jong Min Lee, Jong Woo Kim, Sang Hwan Son, Dae Shik Kim, Jung Chul Suh

Abstract:

The Markov decision process (MDP) based methodology is implemented in order to establish the optimal schedule which minimizes the cost. Formulation of MDP problem is presented using the information about the current state of pipe, improvement cost, failure cost and pipe deterioration model. The objective function and detailed algorithm of dynamic programming (DP) are modified due to the difficulty of implementing the conventional DP approaches. The optimal schedule derived from suggested model is compared to several policies via Monte Carlo simulation. Validity of the solution and improvement in computational time are proved.

Keywords: Monte Carlo Simulation, Dynamic Programming, Weibull distribution, Markov decision processes, periodic replacement

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2 Integrated Simulation and Optimization for Carbon Capture and Storage System

Authors: Jong Min Lee, Taekyoon Park, Seok Goo Lee, Sung Ho Kim, Ung Lee, Chonghun Han

Abstract:

CO2 capture and storage/sequestration (CCS) is a key technology for addressing the global warming issue. This paper proposes an integrated model for the whole chain of CCS, from a power plant to a reservoir. The integrated model is further utilized to determine optimal operating conditions and study responses to various changes in input variables.

Keywords: Simulation, Optimization, Carbon capture and storage, CCS, caron dioxide

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1 Fault Detection of Pipeline in Water Distribution Network System

Authors: Shin Je Lee, Go Bong Choi, Jeong Cheol Seo, Jong Min Lee, Gibaek Lee

Abstract:

Water pipe network is installed underground and once equipped, it is difficult to recognize the state of pipes when the leak or burst happens. Accordingly, post management is often delayed after the fault occurs. Therefore, the systematic fault management system of water pipe network is required to prevent the accident and minimize the loss. In this work, we develop online fault detection system of water pipe network using data of pipes such as flow rate or pressure. The transient model describing water flow in pipelines is presented and simulated using MATLAB. The fault situations such as the leak or burst can be also simulated and flow rate or pressure data when the fault happens are collected. Faults are detected using statistical methods of fast Fourier transform and discrete wavelet transform, and they are compared to find which method shows the better fault detection performance.

Keywords: Fault Detection, fast fourier transform, discrete wavelet transform, water pipeline model

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Abstracts

6 Simulation of a Fluid Catalytic Cracking Process

Authors: Sungho Kim, Jong Min Lee, Dae Shik Kim

Abstract:

Fluid catalytic cracking (FCC) process is one of the most important process in modern refinery indusrty. This paper focuses on the fluid catalytic cracking (FCC) process. As the FCC process is difficult to model well, due to its nonlinearities and various interactions between its process variables, rigorous process modeling of whole FCC plant is demanded for control and plant-wide optimization of the plant. In this study, a process design for the FCC plant includes riser reactor, main fractionator, and gas processing unit was developed. A reactor model was described based on four-lumped kinetic scheme. Main fractionator, gas processing unit and other process units are designed to simulate real plant data, using a process flowsheet simulator, Aspen PLUS. The custom reactor model was integrated with the process flowsheet simulator to develop an integrated process model.

Keywords: Simulation, Process Design, fluid catalytic cracking, plant data

Procedia PDF Downloads 214
5 Modeling and Simulation of Fluid Catalytic Cracking Process

Authors: Sungho Kim, Jong Min Lee, Dae Shik Kim

Abstract:

Fluid catalytic cracking (FCC) process is one of the most important process in modern refinery industry. This paper focuses on the fluid catalytic cracking (FCC) process. As the FCC process is difficult to model well, due to its non linearities and various interactions between its process variables, rigorous process modeling of whole FCC plant is demanded for control and plant-wide optimization of the plant. In this study, a process design for the FCC plant includes riser reactor, main fractionator, and gas processing unit was developed. A reactor model was described based on four-lumped kinetic scheme. Main fractionator, gas processing unit and other process units are designed to simulate real plant data, using a process flow sheet simulator, Aspen PLUS. The custom reactor model was integrated with the process flow sheet simulator to develop an integrated process model.

Keywords: Simulation, Process Design, fluid catalytic cracking, plant data

Procedia PDF Downloads 216
4 Optimal Maintenance and Improvement Policies in Water Distribution System: Markov Decision Process Approach

Authors: Go Bong Choi, Jong Min Lee, Jong Woo Kim, Sang Hwan Son, Dae Shik Kim, Jung Chul Suh

Abstract:

The Markov Decision Process (MDP) based methodology is implemented in order to establish the optimal schedule which minimizes the cost. Formulation of MDP problem is presented using the information about the current state of pipe, improvement cost, failure cost and pipe deterioration model. The objective function and detailed algorithm of dynamic programming (DP) are modified due to the difficulty of implementing the conventional DP approaches. The optimal schedule derived from suggested model is compared to several policies via Monte Carlo simulation. Validity of the solution and improvement in computational time are proved.

Keywords: Monte Carlo Simulation, Dynamic Programming, Weibull distribution, Markov decision processes, periodic replacement

Procedia PDF Downloads 256
3 Fault Detection of Pipeline in Water Distribution Network System

Authors: Shin Je Lee, Go Bong Choi, Jeong Cheol Seo, Jong Min Lee, Gibaek Lee

Abstract:

Water pipe network is installed underground and once equipped; it is difficult to recognize the state of pipes when the leak or burst happens. Accordingly, post management is often delayed after the fault occurs. Therefore, the systematic fault management system of water pipe network is required to prevent the accident and minimize the loss. In this work, we develop online fault detection system of water pipe network using data of pipes such as flow rate or pressure. The transient model describing water flow in pipelines is presented and simulated using Matlab. The fault situations such as the leak or burst can be also simulated and flow rate or pressure data when the fault happens are collected. Faults are detected using statistical methods of fast Fourier transform and discrete wavelet transform, and they are compared to find which method shows the better fault detection performance.

Keywords: Fault Detection, fast fourier transform, discrete wavelet transform, water pipeline model

Procedia PDF Downloads 352
2 Identifying Model to Predict Deterioration of Water Mains Using Robust Analysis

Authors: Shin Je Lee, Go Bong Choi, Jong Min Lee, Gibaek Lee, Sung Jin Yoo

Abstract:

In South Korea, it is difficult to obtain data for statistical pipe assessment. In this paper, to address these issues, we find that various statistical model presented before is how data mixed with noise and are whether apply in South Korea. Three major type of model is studied and if data is presented in the paper, we add noise to data, which affects how model response changes. Moreover, we generate data from model in paper and analyse effect of noise. From this we can find robustness and applicability in Korea of each model.

Keywords: Ecological Sciences, proportional hazard model, survival model, water main deterioration

Procedia PDF Downloads 386
1 Integrated Simulation and Optimization for Carbon Capture and Storage System

Authors: Sungho Kim, Jong Min Lee, Taekyoon Park, Ung Lee, Chonghun Han, Seokgoo Lee

Abstract:

CO2 capture and storage/sequestration (CCS) is a key technology for addressing the global warming issue. This paper proposes an integrated model for the whole chain of CCS, from a power plant to a reservoir. The integrated model is further utilized to determine optimal operating conditions and study responses to various changes in input variables.

Keywords: Simulation, Optimization, Carbon capture and storage, CCS, caron dioxide

Procedia PDF Downloads 157