An efficientoptimalsolutiontothecoilsequencingproblemin electro-galvanizingline

This paperstudiesacoilsequencingproblemthatarisesfromelectro-galvanizinglineinsteelindustry. The problemistofindaprocessingsequenceofsteelcoilssuchthattheswitchingcostsbetween consecutivecoilsareminimizedwhilesatisfyingtechnicalrestrictions.Theproblemcanbedecomposed into severalindependentsub-problems,eachcorrespondingtoaturnwhichisasequenceof continuouslyprocessedcoilswiththesamepost-processingrequirement.Thecoilsineachturncanbe further dividedintoseveralfamilieseachconsistingofthecoilswiththesamewidth.Basedonanalysis of theproblemproperties,atwo-phasepolynomialalgorithmisdevelopedtoobtainanoptimalturn. The sequenceofcoilsinafamilywithgivenboundarycoils(firstandlastcoils)isdeterminedinthefirst phase usingapolynomialdynamicprogrammingalgorithm.Inthesecondphase,theoptimalturnis formedbyanotherpolynomialdynamicprogrammingalgorithmwhichtakestheboundarycoilsfor each familyasstatevariables.Theefficiencyoftheproposedalgorithmisdemonstratedthrough computationalexperiments.