1. School of Engineering, King Mongkut's Institute of Technology Ladkrabang,Bangkok,Thailand,10520
2. Civil Aviation Training Center,Aeronautical Engineering Division,Bangkok,Thailand,10900
3. Silpakorn University,Faculty of Engineering and Industrail Technology,Nakhon Pathom,Thailand,73000
4. Phetchaburi Rajabhat University,Engineering and Industrial,Phetchaburi,Thailand,76000