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| Author(s): |
Livia Maria Pierini
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Instituto de Matemática, Estatística e Computação Científica |
| Defense date: | 2021-05-07 |
| Examining board members: |
Kelly Cristina Poldi;
Carla Taviane Lucke da Silva Ghidini;
Franklina Maria Bragion de Toledo;
Silvio Alexandre de Araújo;
Horacio Hideki Yanasse
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| Advisor: | Kelly Cristina Poldi |
| Abstract | |
Many industrial production and cutting processes have costs associated with setup, production of objects, waste of material in the cutting process, inventory, and transportation which can vary according to each plant's location (factory). The production lot sizing, the planning of cuts, and the transport among plants of a company are interconnected problems that, if optimized in an integrated way, can lead to a reduction in total costs. In the literature, such problems are widely addressed independently. Recently, the lot sizing and cutting stock integrated problem has been the subject of several researches. However, there are no studies in the literature that addresses the integrated problem which also considers multiple plants. This research has as objectives: to propose a more flexible approach than the literature's one to the integrated problem, to propose a mathematical formulation for the integrated problem with multiple plants, and, also, to propose solution methodologies for both. The formulations are inspired by a practical situation in a papermaking industry. The proposed solution methodology consists of a column generation method and a relax-and-fix heuristic integrated with a feasibility heuristic; such procedure was applied to solve the integrated problem and it was also adapted to solve the integrated problem with multiple plants. Computational tests were performed to evaluate the performance of the proposed approaches and the solution methodology. Better results were obtained by the proposed formulation for the integrated problem when compared to the literature's formulation. Regarding multiple plants, the proposed approach presented lower total costs, demonstrating the potential for reducing all considered costs. The applied solution methodology showed satisfactory performance for all the studied instances (AU) | |
| FAPESP's process: | 17/18192-4 - Optimization of the cutting process integrated to the lot sizing in multi-plant industries |
| Grantee: | Livia Maria Pierini |
| Support Opportunities: | Scholarships in Brazil - Doctorate |