A Joint Model Of Preventive Maintenance And Lot-sizing Problem

Production and maintenance are two contradicted factors that are bothsignificant to modern corporation operations. Over attention on productionmay lead to enhance the prohibition of equipment breakdown and thefollowing losses, while over attention on maintenance may lead tounnecessarily reducing outputs. Hence it is of great importance for amanufacturing corporation to find the balanced point of the two. This paperstudies the joint models of PM and CLSP problems, both single and multi-machines.Firstly, based on previous literature review and studies, this thesisdetermines the boundaries and characters of joint models, and proposed multi-item single machine PM and CLSP joint model. The joint model aims tominimize the overall costs including production and maintenance. In order tocombine the two factors, this thesis applies to a rum-based scheme to eliminatethe influence of different capacity utilization, and therefore increase theflexibility of the total system. This thesis designs a heuristic which includes two backward passsmoothing procedure and two forward pass smoothing procedure to obtain theoriginal feasible solution of the single-machine model, as the beginning of animproved genetic algorithm. After local search and numerical iteration, theheuristic proposed is able find the approximate optimal solution. This thesisalso designs two numerical cases, and the outputs to demonstrate that thismodel is able to offer a more flexible and cost-beneficial solution for thisproblem, and the algorithm is efficient and effective.Furthermore, according to the real situation of manufacturingcorporations and recent hot research issues, this thesis proposes a multi-itemsequential machines PM and CLSP joint model. Based on the single-machinemodel, a heuristic is designed to solve the problem, and the solutions andconclusions are good enough to demonstrate this strategy.