Considering in view of China's low price and Japan's high technology, the most important point is the quality of product. To increase the comparative power internationally all workingmen have to fulfill the responsibility to maximize the quality, and this is possible practiced under 'Zero Defect' spirit. To reduce the defect ratio to 'Zero' the workingmen have to recognize own fault, all the manufacturing process should be conducted under 'Fool Proof System', If done under this circumstances, then labor force can work comfortably and safely without nervousness and tiresome. The productivity and quality can increase ultimately and even foreign labor, imbecile child, old-aged labor can participate in work, which can reduce shortage of labor source. Therefore, in this study all defects in manufacturing process, it would be recognized the errors and mistakes caused by human.

• 유병우 | Ryu, Byung-Woo