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A Prediction Model for Coating Thickness Based on PLS Model and Variable Selection

부분최소자승법과 변수선택을 이용한 코팅두께 예측모델 개발

  • Lee, Hye-Seon (Department of Industrial and Management Engineering, POSTECH) ;
  • Lee, Young-Rok (Department of Industrial and Management Engineering, POSTECH) ;
  • Jun, Chi-Hyuck (Department of Industrial and Management Engineering, POSTECH) ;
  • Hong, Jae-Hwa (Instrumentation Research Group, Technical Research Laboratory, POSCO)
  • 이혜선 (포항공과대학교 산업경영공학과) ;
  • 이영록 (포항공과대학교 산업경영공학과) ;
  • 전치혁 (포항공과대학교 산업경영공학과) ;
  • 홍재화 (포스코기술연구소)
  • Received : 20100100
  • Accepted : 20100200
  • Published : 2010.04.30

Abstract

Coating thickness is one of target variables in quality control process in steel industry. To predict coating thickness and to control quality of anti-fingerprint steel coils, ultraviolet-visible spectra are measured. We propose a variable-interval selection procedure based on the variable importance in projection in partial least square model. Using the proposed variable interval selection method, prediction performance gets better in the reduced model than the full model with full spectra absorbance. It is also shown that the first differencing as a data preprocessing technique does work well for the prediction of coating thickness.

산업체 공정과정에서 타겟품질변수의 실시간 예측과 관리는 품질제고, 수익율 향상에 중요한 관건이 된다. 본 연구는 내지문강판의 코팅두께를 비파괴적이고 신속한 방법으로 예측하여 균일한 품질의 강판을 생산하기 위해 UV스펙트럼데이터를 이용한 최적예측모델을 개발하고자 한다. 부분최소자승법에서 변수중요도척도를 이용한 변수선택방법은 노이즈성 영역의 독립변수를 줄임으로써 예측정확도는 높일 수 있으며, 스펙트럼데이터의 경우 원데이터보다 적절한 데이터전처리가 예측정확도를 높이는 정보를 제공하기도 한다. 본 연구에서는 부분최소자승법 예측모텔에서 변수선택방법과 데이터전처리효과가 내지문강판 코팅두께 예측정확도 향상에 기여하는 결과를 제공하고, 스펙트럼 데이터를 이용한 품질변수 예측모델 개발 시 적용할 수 있는 일반적인 변수선택방법과정을 제안한다.

Keywords

References

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