Research Experiences
Postdoctoral Research Fellow (02/2008 – 02/2009)
Center for Intelligent Material Systems and Structures (CIMSS)
Dept. of Mechanical Engineering, Virginia Polytechnic Institute and State University
Director: Prof. Daniel J. Inman (dinman@vt.edu)
Fatigue crack detection using nonlinear impedance features
Multi-scale structural health monitoring incorporating vibration, impedance, and guided waves
Structural damage detection using a DSP-based online guided wave generation/reception system
Adjunct Researcher (04/2008 – 06/2008)
Intelligent IT System Research Center
Korea Electronics Technology Institute
Director: Dr. Hyung-Su Lee (hslee@keti.re.kr)
Developing a ubiquitous sensor network(USN)-based structural health diagnosis system
Developing a USN-GIS (geographic information system)-based intelligent management/ monitoring system for underground facilities
Visiting Scientist (06/2006 – 07/2006)
The Engineering Institute, Los Alamos National Laboratory
Director: Dr. Charles R. Farrar (farrar@lanl.gov)
Developed an electro-mechanical impedance model for piezoelectric sensor self-diagnosis
Visiting Scholar (Supported by KRF-Internship Fellowship) (09/2005 – 08/2006)
Center for Intelligent Material Systems and Structures (CIMSS)
Dept. of Mechanical Engineering, Virginia Polytechnic Institute and State University
Director: Prof. Daniel J. Inman (dinman@vt.edu)
Embedded an outlier analysis-based damage detection algorithm into a miniaturized impedance measuring chip device
Embedded a principal component analysis (PCA)-based data compression algorithm for wireless data transmission into the active sensor node
Applied a wireless digital signal processor (DSP) module to impedance measurements
Incorporated impedance and guided waves-based damage detection techniques for real-time structural health monitoring of railroads
Performed numerical simulations for piezoelectric impedance measurements using ANSYS
Research Graduate Student (03/2002 – 01/2008)
Smart Infra-Structures Technology Center (SISTeC)
Dept. of Civil and Environmental Engineering, KAIST
Advisor/Director: Prof. Chung-Bang Yun (ycb@kaist.ac.kr)
Developed piezoelectric active sensor network system to diagnose structural damage on the welded zone of a steel truss bridge member
Developed a wireless active sensor node for impedance-based structural health monitoring
Developed temperature compensation techniques on piezoelectric impedance measurements
Developed statistical pattern recognition tools including neural networks, support vector machine and outlier analysis to detect and classify structural damages
Incorporated PZT-induced Lamb waves and statistical pattern recognition tools (probabilistic neural network and support vector machine) for on-line health monitoring
Performed both experimental and analytical studies for impedance-based structural health monitoring of reinforced concrete structures