this paper deals with the single machine multi-product lot scheduling problem in which defective items are produced in any production run of each product. we have adopted the common cycle scheduling policy and assumed that the setup times for production of each product can be non-zero. further, we have assumed that defective items will be reworked and the inspection costs during the normal prod...

In this paper we describe the model of an actual problem from the chemical industry, for which we developed a planning and lot-sizing tool. The production process is characterized by a two-stage product structure as well as sequence-dependent setup cost and setup times. The develop a model which is a modified version of the General Lot-sizing and Scheduling Problem (GLSP) framework and combines...

this paper presents a new mathematical model for a bi-objective job shop scheduling problem with sequence-dependent setup times that minimizes the weighted mean completion time and the weighted mean tardiness time. for solving this multi-objective model, we develop a fuzzy multi-objective linear programming (fmolp) model. in this problem, a proposed fmolp method is applied with respect to the o...

different manufacturing enterprises use regularly scheduling algorithms in order to help meeting demands over time and reducing operational costs. nowadays, for a better useofresources and manufacturingin accordance withcustomer needs and given the level ofcompetitionbetweencompanies, employing asuitablescheduling programhasa double importance. conventional productionmethods are constantly subs...

this paper considers the problem of scheduling hybrid flowshops with machine availability constraints (mac) to minimize makespan. the paper deals with a specific case of mac caused by preventive maintenance (pm) operations. contrary to previous papers considering fixed or/and conservative policies, we explore a case in which pm activities might be postponed or expedited while necessary. regardi...