Fuzzy multi objective machine reliability based hybrid flow shop scheduling

Abstract

Many real-world schcduling problems are multi objGctlve and complex in nature, ThaI is, there e>."l scvcral critena lilal must be laken into consideralion when evaluatmg thc quality of thc proposed solullon or schedule. On the other hand consideration of machine rehabilit y is vcry important dllring job allocatioo in each stage to get a realistIC hyhrid flow shop ~chcdulc. This research aims to develop 1'1.'0fuzzy infercnee systems (F1S) fDr the hybrid flow ~hop pwblem, Fir~t FIS is used tD gel the priority of each jDh considering multiple objectives of proces5ing time, duc date and co;t over time. Second FIS is used tQ get machine rehabiIity and availability based priorily using lhe infomlalion of mean time to failure (MTTF) & mcan time to repair (MTTR) of each individual machine of each ~tage. Then the total load is balanced depcnding on !heir reliability and availabl1ity i.e., maximum utili,alion target are detenmlled. An algorithm is developed for grouping, sequencing & aIIDcating the JDbs to the machmes at every stage in such a way lhat tolal percentage Df over utilization is minimllJll. Accmding to this algorithm a cDmputing tDol;s developed and w,lh a case study the entire process i, explained,