ESTCB - Livros ou capítulos de livros
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- Combining DDMRP and CONWIP: A simulation study of the pool-sequencing rulePublication . Fernandes, Nuno O.; Almeida, João; Ferreira, Luís Pinto; Ávila, Paulo; Silva, Sílvio ,Two essential tasks in production planning and control are the generation and the release of orders to the shop floor. In this study order, generation is based on the Demand Driven Materials Requirement Planning system, while order release is based on the CONstant Work-in-Process system. Although the two systems alone have been extensively studied, their combination has received much less attention. In this paper, we address the problem of sequencing replenishment orders generated by the Demand Driven Materials Requirement Planning system to be released by the CONstant Work-in-Process system. Four pool-sequencing rules have been considered. Two of these are used by Demand Driven Materials Requirement Planning for establishing priorities for order planning and order execution. The other two are the First-Come-First-Served rule and a virtual due date rule. Results of a simulation study show that the rules proposed in the Demand Driven Materials Requirement Planning literature for planning and for execution are not the best options for pool-sequencing, particularly for restricted levels of workload allowed on the shop floor.
- A simulation study of DDMRP and MRP manufacturing planning and control systemsPublication . Guedes, N.; Ferreira, Luís Pinto; Silva, F.J.G.; Fernandes, Nuno O.; Silva, Sílvio C.Demand Diven Material Requirements Planning (DDMRP) is a manufacturing planning and control system for fast response to customer requirements in varying and volatile demand and supply markets. DDMRP is an extension of the Material Requirements Planning (MRP) approach that explores the principles of Lean and Theory of Constraints production philosophies to reduce manufacturing response time and make good use of manufacturing resources. It achieves this by promoting flow through selective, reduced, and continuously adjusted inventory levels to synchronize manufacturing and supply with customer market demand. Only a few studies compared the performance of both approaches. However, these studies have not fully addressed the relationship between inventory and service levels. Therefore, this research contributes to a better understanding of this relationship by evaluating and comparing the performance of these two approaches in a multi-product, multi-stage production system. The results of a discrete-event simulation study show that DDMRP outperforms MRP regarding the work-in-process and finished-goods-inventory levels required to achieve a given service level.
- A simulation study of walking-workers assignment strategies based on work zonesPublication . Fernandes, Nuno O.; Thürer, Matthias; Matos, P.This study addresses an “U” shaped assembly line with walking workers and flexible worker assignments. Workers, rather than machines, are the constraining resource in a dual-resource production system. Assignment strategies for walking workers based on Takt Time or restricted time zones of overlap are compared under different production conditions, including processing time variability and worker efficiency conditions. Four strategies have been considered namely: dedicated zoning, relaxed zoning, float zoning, and overlapped zoning. Discrete event simulation is used to assess the performance of these strategies under the controlled release of jobs to the assembly line based on a Constant Work In Process policy. Results show that heterogeneous worker efficiencies strongly impact the performance of all strategies. However, this impact depends on the specific strategy. The study contributes to a better understanding of the behavior of walking workers’ strategies in “U” shaped assembly lines controlled by a Constant Work In Process policy.
- Establishing a regional industry 4.0 electronics hub: The GreenUpPCB modelPublication . Dionísio, Rogério Pais; Ünal, Irem; Delgado-Prieto, M.; Romeral Martinez, L.This chapter presents GreenUpPCB as a regional Industry 4.0 hub for electronics repair and retrofitting, based in Castelo Branco, Portugal. The initiative combines artificial intelligence, machine vision, 3D printing, and automation to extend the life cycle of obsolete printed circuit boards, particularly in renewable energy systems and railway rolling stock. By promoting circular economy practices and reducing electronic waste, GreenUpPCB supports sustainable and resilient industrial operations. The hub also strengthens regional development by linking academic research with industrial needs, offering training, innovation, and high-tech services to local small- and medium-sized enterprises. Its model enables smart manufacturing adoption in low-density territories without dependence on urban clusters. Aligned with the European Chips Act and national strategies for microelectronics, GreenUpPCB demonstrates how regional hubs can contribute to the green and digital transitions across multiple sectors, including energy and transport.
- Preserve or visit? The role of electric mobility in the balance between tourism and conservation in protected areasPublication . Ramos, George; Dionísio, Rogério Pais; Pereira, Paula; Oliveira, Antonella CarvalhoThis article contributes to the debate on sustainable electric mobility as a beneficial element for tourism activities in protected areas. While the topic of sustainable mobility is not new, the recent advancement of electromobility has reignited research interest, predominantly in urban contexts but with promising potential for application in natural spaces. Our objective is to determine the potential for electric mobility to intervene in protected areas, generating benefits for tourism. To this end, we conducted a literature review and compared its findings with a case study of a natural reserve in Portugal. The investigative procedure involved analysing the virtues and conflicts identified in the literature regarding tourism mobility in natural areas, followed by an examination of how these factors manifest in the specific context of the Serra da Malcata Natural Reserve during the development of an INTERREG project. Although comprehensive project indicators are not yet fully available, we conclude that there is a tangible possibility to overcome existing conflicts and maximize identified virtues through electric mobility. This could have a significant impact not only on tourism activities but also on the socioeconomic development of the territories hosting these protected areas.
- Design for automation, edge services, and manufacturing – A React Native interface for collaborative robot palletizing systemsPublication . Torres, Pedro; Esteves, Arthur; Ribeiro, Fillipe; Barbosa, FláviaThis work is part of the PRODUTECH R3 mobilizing agenda project and provides a comprehensive overview of the concepts of Design-for-Automation (DfA), Design-for-Edge Services (DfES), and Design-for-Manufacturing (DfM), highlighting their importance within the Industry 4.0 paradigm. These principles are crucial for developing smart, efficient, and scalable industrial solutions. As a case study, the paper presents the development of an automatic configuration system for a collaborative robotic palletizer, implemented in React Native. The graphical interface simplifies the mosaic configuration process, improves the user experience, and ensures integration with the collaborative robot. Using cutting-edge computing resources, the solution achieves real-time performance and scalability, offering significant value to the company involved and its customers. The study demonstrates how the adoption of these design principles can drive innovation and efficiency in industrial processes, reinforcing the fundamental role of user-centered solutions in the digital transformation of production systems.
- Caraterização das zonas industriais localizadas junto a zonas florestaisPublication . Lopes, Rúben Filipe; Santos, C.C.; Rodrigues, João PauloO presente livro resume os principais resultados do projeto InduForestFire e foi desenvolvido para orientar e colaborar com os agentes dos setores florestal e industrial e com o legislador na criação de regulamentações baseadas em propostas mais eficazes para a gestão dos incêndios florestais em Portugal. Dividido em oito capítulos, o presente livro aborda para além das recomendações de mitigação dos danos provocados por incêndios florestais em zonas industriais, temas contemporâneos, como as novas tendências no controle de incêndios florestais, os incêndios de interface urbano-florestal no mundo e a legislação vigente em Portugal sobre a gestão de incêndios rurais e segurança contra incêndios.
- Caracterização do edificado e tendências de construção em PortugalPublication . Almeida, Miguel; Ribeiro, Luis Mário; Santos, C.C.A presente secção pretende caracterizar o parque habitacional e envolvente (inferior a 2m) em regiões rurais de Portugal mais suscetíveis a incêndios rurais. Ainda que as técnicas construtivas em ambiente rural possam divergir significativamente de uma localização geográfica para outra, refletindo as condições locais, recursos disponíveis, fatores climáticos, culturais e tradições arquitetónica, é fundamental o conhecimento exaustivo do uso e da funcionalidade de uma habitação rural para garantir a segurança dos habitantes e a proteção das edificações. Uma avaliação assente nas condições do edifício, na resistência estrutural, fachadas, vãos, coberturas e acessos, bem como as condições exteriores da envolvente e a maior ou menor proteção e resiliência, permite verificar se o edifício e a envolvente apresentam um risco aceitável. De um modo mais abrangente, destacam-se os estudos desenvolvidos por Ribeiro (2016) e Ribeiro et al. (2020) sobre o impacto do fogo nas estruturas e nos elementos construtivos, os métodos de ignição e a taxa de combustibilidade dos materiais aplicados na envolvente. Tanto os relatórios da ADAI (D. X. Viegas et al., 2017) e (D. X. Viegas et al., 2019), como o relatório da Comissão Técnica Independente (CTI, 2018), analisam o impacto dos incêndios de 2017 nas habitações e instalações empresariais, tendo em conta a defesa e proteção dos aglomerados populacionais, assim como a gestão da interface entre edificações e floresta.
- Recycled reinforced PLA as ecodesign solution for customized prosthesesPublication . Gaspar, Marcelo; Ferraz, Miguel; Ramalho, Armando; Vasco, Joel; Capela, CarlosAdditive manufacturing is a key technology for the digital production of customized prostheses and orthoses. Considering that such assistive devices can be designed to meet specific biomechanical needs based on the actual contours of the patients’ limbs, the ability of those having physical disabilities being able to produce their custom prostheses and orthoses at home would be groundbreaking, by current standards. To such an end, this research aims at selecting sustainable biopolymers that can be used as filaments to produce customized prosthetic sockets using low-cost additive manufacturing technology. Special focus was put into characterizing the use of recycled PLA reinforced with short carbon fibers as filaments for additive manufacturing. Numerical simulation results showed the potential of this sustainable material combination as an ecodesign solution for customized prostheses and orthoses. Such a solution should allow for patients being able to successfully produce and assemble their own customized assistive devices using fused deposition modelling.
- Industrial IoT platforms enabling industry 4.0 digitization towards industry 5.0Publication . Torres, Pedro; Spencer, Geoffrey; Lopes, P.; Santos, FranciscoThis research paper explores the evolution of Industrial In- ternet of Things (IIoT) platforms and their pivotal role in the digitiza- tion of Industry 4.0, as well as their contribution to the transition to- wards Industry 5.0. The characteristics, challenges and opportunities of these platforms will be addressed, highlighting their impact on the digital transformation of industrial operations. Two case studies are unveiled, showcasing the implementation of IIoT platforms. These platforms lever- age cutting-edge technology, notably from the AWS (Amazon Web Ser- vices) ecosystem, enabling the development of solutions grounded in the three pillars of Industry 5.0: human-centered design, sustainability, and resilience. Through these case studies, its aim to illustrate how the in- tegration of AWS technologies contributes to the realization of Industry 5.0 principles, emphasizing a focus on human-centric approaches, sus- tainable practices, and resilient industrial systems.