News & Events
Invited talk:Fatigue crack detection using various smart sensing technologies

Speaker:

Hoon Sohn, Ph.D.
Professor
Department of Civil and Environmental Engineering
Korea Advanced Institute of Science and Technology (KAIST), South Korea

 

Time: 2016-10-14  14:30~16:00
Venue: Civil 
Engineering B504

Chair:Prof Kaoshan DaI
Outline :
In this presentation, a number of fatigue crack detection techniques are developed based on nonlinear ultrasonic modulation for online structural health monitoring and periodic nondestructive testing of metaling structures. First, the working principle of nonlinear ultrasonic modulation and its binding conditions are briefly reviewed. Then, a self-sufficient and self-contained wireless sensor is developed, and its application to online monitoring of Yeongjong Grand Bridge in South Korea is presented. The sensor unit can detect fatigue crack at its early stage (less than 0.1 mm wide), and energy necessary for its operation is harnessed from ambient sun light and bridge vibration. Also, a fully noncontact laser ultrasonic scanning system and associated algorithms are developed for noncontact inspection of micro crack in metallic specimens.. Finally, an online monitoring system is developed for online monitoring of rotating shafts in automobile manufacturing facilities using noncontact air coupled transducers.

 

About the Speaker :

Hoon Sohn received his B.S. (1992) and M.S. (1994) degrees from Seoul National University, Seoul Korea and Ph.D. (1999) from Stanford University, California, USA, all in Civil Engineering. He worked at Los Alamos National Laboratory (LANL) from 1999 to 2004 as a Technical Staff Member and in the Civil and Environmental Engineering Department at Carnegie Mellon University for 2004-2006 as an Assistant Professor. He is now Professor at KAIST (Korea Advanced Institute of Science and Technology), and the Director of ICT Bridge Research Center sponsored by the Ministry of Land, Infrastructure and Transport in Korea (about 25 Million USD project over 5 years). Over last twenty years, his research interest has been in the areas of structural health monitoring, nondestructive testing and sensing technologies. His research interests include guided waves, noncontact laser ultrasonics, structural health monitoring, nondestructive testing, smart materials and sensing, and statistical pattern recognition to name a few. He has published over 120 refereed journal articles, over 270 conference proceedings, and 10 book & book chapters. He was also the recipient of SHM Person-of-Year Award at 2011 International workshop on SHM and 2008 Young Scientists Award in Korea, which is similar to the Presidential Early Career Award from US National Science Foundation (PECASE Award). His work has been funded by the Boeing Company, Samsun Electronics, US Air Force Research Laboratory, US Air Force Office of Scientific Research (US AFOSR), US National Science Foundation, National Research Foundation of Korea, Korea Agency for Defense Development, Hyundai & KIA Motors, Hyundai Heavy Industry, Bombardier, POSCO, Daewoo Construction.


All interested are welcome!