Our interest is in developing effective mathematical models and numerical procedures for various types of physical and mechanical problems. We have been studying the finite element method and boundary element method for analyzing structural problems and problems related to fluid뱒tructure interactions. We have mainly worked in the following areas:
Development of Shell and Beam Finite Elements
Shell and beam structures are widely used in countless engineering applications, and the finite element method has been the dominant tool used to analyze such structures. We developed a new three-node triangular shell finite element that performed as well as the state-of-the-art four-node shell element does in linear and nonlinear analyses. Our shell element has been employed in ADINA, a well-known commercial finite-element software.
We also proposed the continuum-mechanics-based beam finite element for linear and nonlinear analyses. This beam element can handle complicated 3D geometries, and consider fully coupled warping effects with bending, shearing, and stretching.

Hydrodynamic Analysis of Flexible Floating Structures
Since 2009, we have studied hydrodynamic analysis of deformable floating structures, in which a complete mathematical model and effective numerical procedures were developed using finite and boundary element methods. Moreover, various experimental tests were performed in ocean basins. A direct coupling method was developed for 3D hydroelastic analysis of floating structures in surface gravity water waves. Using this method, problems related to the internal and external fluid뱒tructure interaction can be solved effectively in both frequency and time domains. The developed numerical codes have been adopted by Hyundai Heavy Industries, Samsung Heavy Industries, Korea Institute of Machinery and Materials, and Korea Institute of Energy Research, among others.


Reduction of Dynamic Finite Element Models
In structural dynamics, reduced-order modeling methods have been popular for decades in order to reduce the degrees of freedom of a large finite element model. We developed high-performance reduced-order modeling methods: the enhanced Craig-Bampton (CB) method, the higher-order CB method, the enhanced AMLS method, and the algebraic dynamic condensation method. The methods construct significantly accurate reduced-order models with computational efficiency compared to related previous methods. We also developed accurate error-estimation methods for the CB method, Guyan reduction, and the FCMS method.
Ocean Structural Systems
We proposed a new concept for offshore nuclear power plants and emergency passive cooling systems for them. We have conducted extensive research on the safety features of gravity-based nuclear power plants in ocean environments. Such gravity-based ocean nuclear power plants can mount APR1400 (Advanced Power Reactor - 1400 MWe) and SMART (System-integrated Modular Advanced ReacTor). We also developed a ballast calculation system for the world셲 first offshore floating dock. The system can manage the dimensions of offshore blocks when they are erected during construction. This work has been formally recognized as the best technology developed by Samsung Heavy Industries.
Remote Control System for Live Animals
We developed a system that can remotely guide a live animal using body-attached devices and special stimuli. The proposed system provides virtual-reality-based or virtual-experience-based animal control. The proposed technology could overcome well-known limitations to small conventional robotic systems. A simple device attached to a turtle셲 carapace can make the turtle stop, turn, and follow a path. We also developed a robot to provide directional information to the turtle through a head-mounted display, and to provide food as a reward to reinforce this behavior. In our experiment, the robot successfully guided the turtle셲 motion. Recently, we developed a system to steer mice using an object-craving brain circuit.


NRF (븳援뿰援ъ옱떒) | Core technology development of SMART mounted 100MWe floating-type NPP (SMART 깙옱 100MWe 遺쑀떇 썝옄젰 諛쒖쟾냼 빑떖 湲곕컲湲곗닠媛쒕컻) | Jun 2014-May 2015. 
NRF (븳援뿰援ъ옱떒) | Development of a three dimensional hydroelastic analysis tool for floating structures (遺쑀떇 빐긽援ъ“臾쇱쓽 3李⑥썝 쑀깂꽦 빐꽍 봽濡쒓렇옩 媛쒕컻(썑냽1李⑤뀈)) | May 2014-Apr 2017.
KAIST (븳援怨쇳븰湲곗닠썝) | Development of Floating Type Ocean Wind Power System with Economic Competitive Edge (寃쎌웳젰쓣 媛뽰텣 遺쑀떇 빐뼇 뭾젰 떆뒪뀥 媛쒕컻) | Mar 2014-Dec 2018.
KIER (븳援뿉꼫吏湲곗닠뿰援ъ썝) | 遺쑀떇 뭾젰諛쒖쟾湲 븯遺떆뒪뀥 媛쒕뀗 諛 뿰룞빐꽍湲곗닠 媛쒕컻 | Jan 2014-Oct 2014.
KRRI (븳援泥좊룄湲곗닠뿰援ъ썝) | 궡吏꾪빐꽍, 뙆옉 諛 빐瑜섎젰 빐꽍떆뒪뀥 닔移섎え뜽 媛쒕컻 | Apr 2013-Dec 2015.
SHI (궪꽦以묎났뾽) | FEM Modeling Core 媛쒕컻 | Apr 2013-Apr 2014.
KODIPA (듅닔踰뺤씤븳援諛⑹옱삊쉶) | Development of Analysis Technology for Damage to Civil Structures from Tsunami (吏吏꾪빐씪뿉 쓽븳 援ъ“臾 뵾빐遺꾩꽍湲곗닠 媛쒕컻) | Apr 2012-Apr 2015.

DSME (슦議곗꽑빐뼇) | Safety evaluation and enhancement of GBS type Ocean Nuclear Power Plant (GBS瑜 솢슜븳 빐긽썝옄젰 諛쒖쟾 뵆옖듃쓽 븞젙꽦 룊媛 諛 利앹쭊) | Mar 2012-Dec 2012.

KAIST (븳援怨쇳븰湲곗닠썝) | Remote control system for animals using behavior biology (뻾룞 깮臾쇳븰쓣 넻븳 빐뼇 룞臾쇱쓽 썝寃⑹젣뼱 떆뒪뀥 媛쒕컻) | Jan 2012-Jan 2013.
SHI (궪꽦以묎났뾽) | OFD 깙옱臾 젙룄 愿由щ 쐞븳 쑀븳슂냼 援ъ“紐⑤뜽 媛쒕컻 | Aug 2011-Feb 2012.
MKE (吏떇寃쎌젣遺) | Advanced education track for infrasystems of ocean renewable energy (빐뼇 떊옱깮뿉꼫吏 씤봽씪떆뒪뀥 援ъ텞 怨좉툒 듃옓) | Jun 2011-May 2016.
NRF (븳援뿰援ъ옱떒) | Development of a three dimensional hydroelastic analysis tool for floating structures (遺쑀떇 빐긽援ъ“臾쇱쓽 3李⑥썝 쑀깂꽦 빐꽍 봽濡쒓렇옩 媛쒕컻) | May 2011-Apr 2014.
KAIST (븳援怨쇳븰湲곗닠썝) | Extreme risk preparedness (옱궃鍮 諛 쓳뿭웾 媛뺥솕諛⑹븞 諛 湲곗닠뿰援) | Jan 2011-Dec 2012.
KAIST (븳援怨쇳븰湲곗닠썝) | Virtual reality-based remote control system for animals (媛긽 옄洹뱀쓣 넻븳 臾쇨퀬湲 썝寃 쑀룄 湲곗닠 뿰援) | Sep 2010-Dec 2011.
KEIT(븳援궛뾽湲곗닠룊媛愿由ъ썝) | Automatic ship-to-ship docking system (꽑諛뺢컙 옄룞 룄궧 떆뒪뀥) | May 2010-Jun 2011.
POSCO (룷뒪肄) | New product development of transportable ocean nuclear power plants (빐긽 슫넚씠 媛뒫븳 紐⑤뱢삎 빐긽 썝옄젰諛쒖쟾 떆뒪뀥 떊긽뭹 媛쒕컻) | Nov 2010-Apr 2011.
KICT (븳援嫄댁꽕湲곗닠뿰援ъ썝) | Total Lagrangian 젙떇솕뿉 湲곕컲븳 蹂쐞 돇 슂냼쓽 媛쒕컻 諛 諛뺥뙋 援ъ“臾 꽑삎 醫뚭뎬 빐꽍 | Jun 2010-Dec 2010.
KAIST-Changwon (븳援怨쇳븰湲곗닠썝-李쎌썝) | Development of presuure vessel for CO2 carrier (CO2 슫諛섏꽑 븬젰 슜湲 媛쒕컻) | Jan 2010-May 2010.
KAIST (븳援怨쇳븰湲곗닠썝) | Optimal design and motion analysis on semisubmersible mobile harbor (諛섏옞닔떇 紐⑤컮씪븯踰(MH-B1)쓽 嫄곕룞빐꽍 諛 理쒖쟻꽕怨) | Jun 2009-Dec 2009.
FORTRAN codes for linear elastic analysis of 2D plane stress problems (developed by CMSS) 

MATLAB codes for hydroelastic analysis of floating beams (developed by CMSS) 

Freeware for 3D hydroelastic analysis of floating structures (will be distributed soon)

Freeware for extracting (x,y) data from scanned graphs (developd by PS Lee) 
CMSS Archive <- Members only access