Research On Flow Shop Optimization Of Hybrid Make-To-Order And Make-To-Stock Precast Component Production

Since the reform of China entered a new era,the prefabricated building is considered to be the new power injected into the transformation and innovation of China’s construction industry.It shows advantages in terms of time,quality and energy consumption.There is a coexist of non-standard components and standard components in prefabricated buildings.Non-standard components are manufactured in make-to-order mode(MTO)mode,and standard components are manufactured in make-to-stock(MTS)mode.The mix of the two modes of production poses a serious challenge to the manufacturing enterprises of precast components.Efficient and stable production scheduling of precast components plays a vital role in the sustainable and healthy development of assembled buildings.For this reason,this paper studies the flow shop optimization of hybrid make-to-order and make-to-stock precast component production.This study proposes two models of MTO production and hybrid MTO-MTS production,respectively,and develops a whale optimization algorithm(WOA)and a two-stage heuristic based on WOA to solve the corresponding model.The validity and Superiority of proposed methods and the hybrid MTO-MTS production mode are verified by numerical simulation analysis.The main work and research contributions of this paper summarize as follows:(1)For the customization of precast components in MTO mode,this study combines the process flow of prefabricated construction production.The defection of fixed mold quantity constraint is improved,and a flow shop production scheduling model with the objective of minimizing the cost of delivery error in MTO mode is developed.The WOA is developed to solve the scheduling problem of MTO precast components.Based on the original algorithm,the WOA applies the existing heuristic algorithm.The hybrid initial population is introduced to improve the pertinence of the optimization.Moreover,the iterative local search is adopted to improve the search ability of the algorithm.(2)This study considers the trend of standardization of precast components,introduces the conversion cost of production mode.A hybrid MTO-MTS production scheduling model based on the MTO production model is established to minimize the total delivery error cost.A two-stage heuristic based on WOA is developed to perform the hybrid MTO-MTS production scheduling,and to ensure the on-time production of MTO.(3)The performance of the proposed WOA is compared with PSO algorithm by an numerical test.The effectiveness of the two-stage heuristic method to solving MTO-MTS production scheduling is verified,and the difference between hybrid MTO-MTS and MTO production mode is compared.