Strong guidance on mitigating the effects of uncertainties in the brass casting blending problem: a hybrid optimization approach

Abstract

The scrap charge optimization problem in the brass casting process is a critical management concern that aims to reduce the charge while preventing specification violations. Uncertainties in scrap material compositions often cause violations in product standards. In this study, we have discussed the aleatory and epistemic uncertainties and modelled them by using probability and possibility distributions, respectively. Mathematical models including probabilistic and possibilistic parameters are generally solved by transforming one type of parameter into the other. However, the transformation processes have some handicaps such as knowledge losses or virtual information production. In this paper, we have proposed a new solution approach that needs no transformation process and so eliminates these handicaps. The proposed approach combines both chance-constrained stochastic programming and possibilistic programming. The solution of the numerical example has shown that the blending problem including probabilistic and possibilistic uncertainties can be successfully handled and solved by the proposed approach.

Keywords:

• blending problem
• stochastic programming
• possibilistic programming
• brass casting

Acknowledgements

The authors are indebted to the anonymous referees, whose constructive comments and help led to a substantial improvement in this paper.