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Details

  • Name

    Manuel Pereira Lopes
  • Role

    Senior Researcher
  • Since

    19th January 2022
001
Publications

2024

The Identical Parallel Machine Scheduling Problem with Setups and Additional Resources

Authors
Soares, A; Ferreira, AR; Lopes, MP;

Publication
FLEXIBLE AUTOMATION AND INTELLIGENT MANUFACTURING: ESTABLISHING BRIDGES FOR MORE SUSTAINABLE MANUFACTURING SYSTEMS, FAIM 2023, VOL 2

Abstract
This paper studies a real world dedicated parallel machine scheduling problem with sequence dependent setups, different machine release dates and additional resources (PMSR). To solve this problem, two previously proposed models have been adapted and a novel objective function, the minimisation of the sum of the machine completion times, is proposed to reflect the real conditions of the manufacturing environment that motivates this work. One model follows the strip-packing approach and the other is time-indexed. The solutions obtained show that the new objective function provides a compact production schedule that allows the simultaneous minimisation of machine idle times and setup times. In conclusion, this study provides valuable insights into the effectiveness of different models for solving PMSR problems in real-world contexts and gives directions for future research in this area using complementary approaches such as matheuristics.

2023

Technician Routing and Scheduling Problem: A Case Study

Authors
Nunes, C; Lopes, MP;

Publication
QUALITY INNOVATION AND SUSTAINABILITY, ICQIS 2022

Abstract
The problem of routing and scheduling of technicians is a problem that technical assistance and maintenance companies face nowadays, market competitiveness requires quick response, service diversification, and customer satisfaction. The relationship between competitiveness and profitability of companies involves the effective management of their resources. The work developed addresses a real problem of a major Portuguese company providing technical assistance to the home, a varied set of services (need for specific skills and execution times) must be scheduled for a set of technicians with heterogeneous skills and geographical locations (start and end of the route) based on their different places of residence. The results show a considerable increase in the efficiency levels of the solution obtained when compared to the company's current solution and reveals that the lack of homogeneity of skills among technicians and the variation in service flows are factors that should be considered in the operational management of resources and the contracting of work, and that the increase in working hours can also contribute to improving the efficiency of the process.

2022

Performance Evaluation of Dispatching Rules and Simulated Annealing in a Scheduling Problem from a Quality-Functionality Perspective

Authors
Almeida, D; Ferreira, LP; Sa, JC; Lopes, M; da Silva, FJG; Pereira, M;

Publication
15TH INTERNATIONAL CONFERENCE INTERDISCIPLINARITY IN ENGINEERING

Abstract
Production scheduling generates a direct impact on several aspects of manufacture, such as the number of delays in delivery to customers, total flow time, as well as the percentage of equipment used. It must, therefore, constitute a priority in production management, which should seek to implement scheduling techniques that will lead to positive results from the perspective of the quality of the solution. However, the methodology cannot overlook the functional aspect of the time which has elapsed until the solution is reached. This study is based on a real and specific module software improvement into a company devoted to the development of ERP software systems (Enterprise Resource Planning). It presents a solution for the production scheduling module focused on flow-shop operations, comprising a total of nine dispatching rules. An additional solution for scheduling is also proposed, which resorts to metaheuristic simulated annealing. Both solutions are compared to each other by using the quality-functionality binomial approach. These two environments are further contrasted with a third, where no effective solution for production scheduling exists. The environment which includes scheduling through dispatching rules was compared to the environment where no production scheduling was implemented. The results obtained from this analysis show an improvement of 13%. The simulated annealing solution presents an improvement of 3,6% when compared to a solution which uses dispatching rules. This improvement implies one extra minute in the calculation of the final solution.

2019

Capacitated Vehicle Routing Problem with Heterogeneous Fixed Proprietary Fleet and Outsourcing Delivery—A Clustering-Based Approach

Authors
Bertoluci, R; Ramos, AG; Lopes, M; Bastos, J;

Publication
Springer Proceedings in Mathematics and Statistics

Abstract
This paper describes a solution method that was created with the objective of obtaining a more efficient finished goods distribution process for a food industry company. The finished goods distribution process involves the use of the companys own fleet to serve a specific group of customers, and the use of outsourcing transportation services that can make direct and transshipment customer deliveries. The complexity of the problem is due to the need to decide which customers should be served by each of the outsourcing transportation services, direct or transshipment, and to find cost efficient solutions for the multiple vehicle routing problems created. First, an original clustering method consisting of a logical division of the customer orders using a delivery ratio based on the transportation unit cost, distance and order weight, is used to define customer clusters by service type. Then, an exact method based on a mixed integer programming model, is used to obtain optimal vehicle routing solutions, for each cluster created. The solution method for the company real instances, proved able to reach the initial proposed objectives and obtain promising results that suggest an average reduction of 34% for the operational costs, when compared to the current distribution model of the company. © 2019, Springer Nature Switzerland AG.

2019

Optimization of the cold profiling process through SMED

Authors
Vieira, T; Sá, JC; Lopes, MP; Santos, G; Felix, MJ; Ferreira, LP; Silva, FJG; Pereira, MT;

Publication
29TH INTERNATIONAL CONFERENCE ON FLEXIBLE AUTOMATION AND INTELLIGENT MANUFACTURING (FAIM 2019): BEYOND INDUSTRY 4.0: INDUSTRIAL ADVANCES, ENGINEERING EDUCATION AND INTELLIGENT MANUFACTURING

Abstract
In a more and more competitive and industrialized market, it is essential that companies realize that the way forward must go through the optimization of their production processes, reducing the costs and increasing product quality. Nowadays it's necessary to adopt innovative management models that can provide increased productivity at minimal costs, such as the Lean thinking. The metalworking industry is integrated into one of the most competitive existing markets in Portugal. Given this, it's fundamental to reduce the waste in all sectors of the production process, using the good Lean principles and practices, such as the Single Minute Exchange of Die, also known as SMED methodology. This paper presents a project of implementing the SMED methodology in the cold profiling process, in a population of five different profiling machines. The results of the SMED implementation show an average OEE improvement of 10,8%.

Supervised
thesis

2023

Programação de máquinas paralelas dedicadas com famílias de setups, recursos adicionais e datas de entrega

Author
ANA RITA BARBOSA MOURA MOTA FERREIRA

Institution
IPP-ISEP

2023

Escalonamento de máquinas paralelas dedicadas com famílias de setup e recursos adicionais

Author
ÂNGELO EMANUEL VIEIRA SOARES

Institution
IPP-ISEP

2023

Gestão de Inventários de uma cadeia de retalho

Author
JORGE RICARDO CORDEIRO DE OLIVEIRA MONTEIRO ALVES

Institution
IPP-ISEP

2023

DEM Timetabling Project ? Development/implementation of an algorithm to support the creation of timetables

Author
INÊS MANUELA AFONSO MARRÃO

Institution
IPP-ISEP

2022

DESENVOLVIMENTO E AVALIAÇÃO DE UMA ESTRATÉGIA DE GESTÃO ENERGÉTICA EM FCHEV

Author
CARLA ALEXANDRA SILVA REISINHO

Institution
IPP-ISEP