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Demand driven material requirements planning: using the buffer status to schedu...
Fernandes, Nuno O.; Guedes, Nelson; Thürer, Matthias; Ferreira, Luís Pinto; Ávila, Paulo; Silva, Sílvio do CarmoDemand Driven Material Requirements Planning argues that production re-plenishment orders should be scheduled on the shop floor according to the buffers’ on-hand inventory. However, the actual performance impact of this remains largely unknown. Using discrete event simulation, this study com-pares scheduling based on the on-hand inventory, with scheduling based on the inventory net flow position. Results of our...
DDMRP relative priority for production execution: an assessment by simulation
Fernandes, Nuno O.; Thürer, Matthias; Silva, Sílvio do CarmoDemand-Driven Material Requirements Planning (DDMRP) was designed to improve supply chain performance in complex and uncertain environments. Literature on the topic suggests that production replenishment orders should be dispatched for execution based on the buffers’ penetration ratio of the products ordered, which is a measure of protection against stock depletion. However, the actual performance impact of thi...
Planeamento e controlo da produção em ambientes dinâmicos : DDMRP
Fernandes, Nuno O.; Silva, Sílvio do CarmoFlexibilidade, eficiência e eficácia ao nível da atividade produtiva são importantes vantagens competitivas para as empresas industriais responderem à volatilidade dos mercados atuais. Os sistemas tradicionais de Planeamento e Controlo da Produção, ainda largamente usados na indústria, não foram desenvolvidos para operar adequadamente neste contexto. A abordagem recentemente proposta, conhecida como Demand-Driv...
POLCA control in two-stage production systems
Fernandes, Nuno O.; Thürer, Matthias; Mirzaei, Nima; Ferreira, Luís Pinto; Silva, Francisco J.G.; Silva, Sílvio do CarmoPOLCA (Paired-cell Overlapping Loops of Cards with Authorization) is a decision support system for material flow control under Quick Response Manufacturing. It operates in the context of low-volume, high-mix, and cellular manufacturing. While there is an increasing literature on POLCA performance, current studies usually assume full availability of components (or parts) at assembly stations, neglecting parts ma...
Literature review on autonomous production control methods
Martins, Luis; Varela, Leonilde; Fernandes, Nuno O.; Silva, Sílvio do Carmo; Machado, JoséProduction environments are becoming more complex and dynamics. This is influenced by external factors related with products’ characteristics and costumers’ requirements and internal factors related with processing times variability, machine failures, setup times, between others. To face this increasing complexity and dynamics, it is crucial to have effective production control methods, considering Interoperabi...
Workload control and optimised order release: an assessment by simulation
Fernandes, Nuno O.; Thürer, Matthias; Pinho, Tatiana; Torres, Pedro; Silva, Sílvio do CarmoAn important scheduling function of manufacturing systems is controlled order release. While there exists a broad literature on order release, reported release procedures typically use simple sequencing rules and greedy heuristics to determine which jobs to select for release. While this is appealing due to its simplicity, its adequateness has recently been questioned. In response, this study uses an integer li...
POLC-A: an assessment of POLCA’s authorization element
Thürer, Matthias; Fernandes, Nuno O.; Stevenson, Mark; Silva, Cristóvão; Silva, Sílvio do CarmoPOLCA (i.e. Paired-cell Overlapping Loops of Cards with Authorization) is a card-based production control approach developed to support the adoption of Quick Response Manufacturing. POLCA’s control mechanism is unique since it combines a card-based element (the paired cell overlapping loops of cards) with a higher-level Material Requirements Planning system for release authorization. POLCA has been applied in p...
Lot splitting under load-limiting order release in high-variety shops: an asses...
Thürer, M.; Fernandes, Nuno O.; Silva, Sílvio do Carmo; Stevenson, M.Lot splitting is an important approach for shops that compete on short delivery times. Similarly, such shops can benefit from load-limiting order release mechanisms that balance workloads and regulate throughput times. Yet few studies have examined the combined effect of lot splitting and load-limiting order release. We use simulation to assess the combined effect of lot splitting and Paired-cell Overlapping Lo...
Iterative optimization-based simulation: a decision support tool for job release
Fernandes, Nuno O.; Dehghanimohammadabadi, M.; Silva, Sílvio do CarmoJob release is an essential scheduling function and a core part of every production planning and control system. Essentially, job release has to do with the timing and the jobs to release on to the shop floor, in such way that, a balanced and restricted workload is achieved. In this paper, an Iterative Optimization-based Simulation (IOS) decision support tool is proposed for job release. This is in line with In...
Improving materials flow through autonomous production control
Fernandes, Nuno O.; Martins, Tiago; Silva, Sílvio do CarmoAutonomous Production Control (APC) aims at improving production systems performance through fast and flexible reaction to changes in dynamic environments. In this paper, a new APC method for job routing decision-making is proposed and its performance compared with that of two other APC methods, namely the Queue Length Estimator and the Pheromones, and with two conventional control strategies – a centralized an...