As technique that can contribute in quality improvement in design process to overcome shortcoming of traditional quality control, call design or development department quality control activity that is achieved to reduce gun damage shuddering at circle minimizing change or side effect of product performance as off-line quality control. This paper discuss optimal process design of investment projects expansion and replacement investment on each line or individual in the production. Generally optimal plant design has add to a few method by Subsidiary means with use a especial method. And then in this paper, a Robust design is presented, which may be effective to the processes appraisal or improvement. We propose that should make a optimal plant design model for reducing field failure rate to assign by real data on different factors in plant system. Using this model, robust design of taguchi method used in this comprehensive method for reducing field failure rate in plant system.

Abstract
 1. 서론
 2. 현행 생산시스템의 분석
 3. 인자의 확인 및 분석 결과
 4. 시스템 결과 분석
 5. 참고문헌

• 양광모
• 서장훈
• 박진홍
• 강경식