Rocío Alfaro

Models for MMSP-W considering workstation dependencies: A case study of Nissan’s Barcelona plant

In this article, we present two formulations and their unification for the Mixed-Model Sequencing Problem with Workload Minimisation (MMSP-W) for production lines with serial workstations and parallel homogeneous processors. The models were executed in Solver CPLEX, with reference instances and with a case study of Nissan’s Powertrain plant in Barcelona. Different situations were analysed to evaluate investments in projects designed to improve process and product design and reduce work overloads in the line at short-, intermediate- and long-term intervals.

Incorporating Ergonomics Factors into the TSALBP

Mixed-product assembly lines have ergonomic risks that can affect the worker productivity and lines. This work proposes to incorporate ergonomic factors to the TSALBP (Time and Space constrained Assembly Line Balancing Problem). Therefore, we present several elements for new models to assign the tasks to a workstation considering technological, management and ergonomic factors.

Impact of the Production Mix Preservation on the ORV Problem

We present a sequencing problem given on JIT (Just In Time) manufacturing environments, with the objective of minimizing the variation of manufacturing rates (ORV: Output Rate Variation). Specifically, we propose an extension based on requiring to the sequences the preservation of the production mix throughout the products manufacturing. To solve the ORV and the extended problem, we propose algorithms based on BDP (Bounded Dynamic Programming) and we perform two computational experiments based on instances from the literature.

A bounded dynamic programming algorithm for the MMSP-W considering workstation dependencies and unrestricted interruption of the operations

In this paper, we propose a procedure based on Bounded Dynamic Programming (BDP) to solve the Mixed-Model Sequencing Problem with Workload Minimisation (MMSP-W), with serial workstations and unrestricted (or free) interruption of the operations. We performed a computational experiment with 225 instances from the literature. The results of our proposal are compared with those obtained through the CPLEX solver.

Incorporating the Work Pace Concept into the MMSP-W

This work proposes an extension for the MMSP-W (Mixed-Model Sequencing Problem with Work overload Minimization) with variable processing times by the incorporation of the work pace or work speed concept. A computational experience, linked to a case study of Nissan Powertrain plant in Barcelona, is carried out to compare the performance of the reference model with the new proposed model.

Modeling and Solving a Variant of MMSP-W Problem with Production Mix Restrictions

In this paper, we propose a procedure based on Bounded Dynamic Programming (BDP) to solve the Mixed-Model Sequencing Problem with Work overload Minimisation (MMSP-W), with serial workstations, unrestricted (or free) interruption of the operations and with production mix restrictions.In this paper, we propose a procedure based on Bounded Dynamic Pr o- gramming ( BDP ) to solve the Mixed - Model Sequencing Problem with Work ove r- load Minimisation ( MMSP - W ), with serial workstations, unrestricted (or free) int e- rruption of the operations and with production mix restrictions.

Performance of Bounded Dynamic Programming Applied to a Variant of the MMSP-W Problem

In this study we present a formulation for the MMSP-W (Mixed Model Sequencing Problem with Work overload Minimization) for productions lines with both serial workstations and rules for interrupting operations. We propose a combination of the models M5 and M6 proposed by Bautista and Cano (Eur J Oper Res 210:495–513, 2011) and analyze the results obtained, using the BDP (Bounded Dynamic Programming), through a case study of the powertrain line of the Nissan plant in Barcelona.

Algoritmos GRASP para solucionar el problema Blocking Flow Shop

Resumen Se resuelve el Blocking Flow Shop Problem (BFSP), consiste en determinar una secuencia de piezas procesadas por una ĺinea de maquinas sin espacios de almacenamiento entre ellas. Para ello, se implementan 14 algoritmos heuŕisticos Greedy Randomized Adaptive Search Procedure (GRASP) aplicados a las 60 primeras instancias de Taillard. Los resultados obtenidos con los 7 procedimientos que incorporan la heuŕistica de Nawaz son los mas competitivos cuando se comparan con otros los de la literatura.

Incorporating Regularity of Required Workload to the MMSP-W with Serial Workstations and Free Interruption of the Operations

We propose a mathematical model to solve an extension to the mixed-model sequencing problem with work overload minimization (MMSP-W) for production lines with serial workstations and parallel homogeneous processors and regularizing the required workload. We performed a computational experience with a case study of the Nissan engine plant in Barcelona.