Good morning? It's rainy in south Korea. I'm working at LG Electronics for MES project. Applying process is for building compressor, which consists of many parts. In detail, compressor consists 5 major parts and many minor parts. One of our project goal is, as is natural for general MES systems, to track the part of bad quality. Our process includes some 'rough' steps such as welding, dropping in the water to check sealing, and high pressure. Bar-code sticker made of paper would not bear these SEVERE environments. (What kind of paper can stand flame from welding or be wetting by water?) Then, how can we accomplish our goal of 'tracking parts?' without using bar-code? Is there any good alternatives for bar-code sticker? Any ideas will be welcomed, and we express our acknowledgements in advance. Have a good day!