Browsing by Author "Ferreira, Luís"
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- Agile Project Management: A Communicational Workflow ProposalPublication . Loiro, Carina; Castro, Helio; Ávila, Paulo; Cruz-Cunha, Maria Manuela; Putnik, Goran D.; Ferreira, LuísEmbracing agility brings change to companies and everyone involved, so people have a fundamental role in project development. It is essential that teams have a good communication, motivation and concern about quality and client satisfaction, Agile Manufacturing is using Agile Project Management to provide the right team to performance difficult tasks and achieve goals. This paper proposes a team that deals with Agile Project Management, named as AGILE team, composed by a product owner, a team leader and team members, and a communication workflow proposal concerning the conjunction of 3 momentums (requirements analyze, planning and design) along the Agile Project Management. The proposed model is being implemented in a lightening manufacturing company in a very early stage.
- An Explicit GTS allocation algorithm for IEEE 802.15.4Publication . Chen, Jianxin; Ferreira, Luís; Tovar, EduardoThe IEEE 802.15.4 standard provides appealing features to simultaneously support real-time and non realtime traffic, but it is only capable of supporting real-time communications from at most seven devices. Additionally, it cannot guarantee delay bounds lower than the superframe duration. Motivated by this problem, in this paper we propose an Explicit Guaranteed time slot Sharing and Allocation scheme (EGSA) for beacon-enabled IEEE 802.15.4 networks. This scheme is capable of providing tighter delay bounds for real-time communications by splitting the Contention Free access Period (CFP) into smaller mini time slots and by means of a new guaranteed bandwidth allocation scheme for a set of devices with periodic messages. At the same the novel bandwidth allocation scheme can maximize the duration of the CFP for non real-time communications. Performance analysis results show that the EGSA scheme works efficiently and outperforms competitor schemes both in terms of guaranteed delay and bandwidth utilization.
- Data Science for Industry 4.0 and Sustainability: A Survey and Analysis Based on Open DataPublication . Castro, Helio; Costa, Filipe; Ferreira, Tânia; Ávila, Paulo; Cruz-Cunha, Manuela; Ferreira, Luís; Putnik, Goran D.; Bastos, JoãoIn the last few years, the industrial, scientific, and technological fields have been subject to a revolutionary process of digitalization and automation called Industry 4.0. Its implementation has been successful mainly in the economic field of sustainability, while the environmental field has been gaining more attention from researchers recently. However, the social scope of Industry 4.0 is still somewhat neglected by researchers and organizations. This research aimed to study Industry 4.0 and sustainability themes using data science, by incorporating open data and open-source tools to achieve sustainable Industry 4.0. To that end, a quantitative analysis based on open data was developed using open-source software in order to study Industry 4.0 and sustainability trends. The main results show that manufacturing is a relevant value-added activity in the worldwide economy; that, foreseeing the importance of Industry 4.0, countries in America, Asia, Europe, and Oceania are incorporating technological principles of Industry 4.0 in their cities, creating so-called smart cities; and that the industries that invest most in technology are computers and electronics, pharmaceuticals, transport equipment, and IT (information technology) services. Furthermore, the G7 countries have a prevalent positive trend for the migration of technological and social skills toward sustainability, as it relates to the social pillar, and to Industry 4.0. Finally, on the global scale, a positive correlation between data openness and happiness was found.
- Enabling inter-domain transactions in bridge-based hybrid wired/wireless PROFIBUS networksPublication . Ferreira, Luís; Tovar, Eduardo; Alves, MárioThe marriage of emerging information technologies with control technologies is a major driving force that, in the context of the factory-floor, is creating an enormous eagerness for extending the capabilities of currently available fieldbus networks to cover functionalities not considered up to a recent past. Providing wireless capabilities to such type of communication networks is a big share of that effort. The RFieldbus European project is just one example, where PROFIBUS was provided with suitable extensions for implementing hybrid wired/wireless communication systems. In RFieldbus, interoperability between wired and wireless components is achieved by the use specific intermediate networking systems operating as repeaters, thus creating a single logical ring (SLR) network. The main advantage of the SLR approach is that the effort for protocol extensions is not significant. However, a multiple logical ring (MLR) approach provides traffic and error isolation between different network segments. This concept was introduced in, where an approach for a bridge-based architecture was briefly outlined. This paper will focus on the details of the inter-Domain Protocol (IDP), which is responsible for handling transactions between different network domains (wired or wireless) running the PROFIBUS protocol.
- Fieldbus networks: real-time from the perspective of the application tasksPublication . Mendes, André; Ferreira, Luís; Tovar, EduardoFieldbus communication networks aim to interconnect sensors, actuators and controllers within distributed computer-controlled systems. Therefore they constitute the foundation upon which real-time applications are to be implemented. A potential leap towards the use of fieldbus in such time-critical applications lies in the evaluation of its temporal behaviour. In the past few years several research works have been performed on a number of fieldbuses. However, these have mostly focused on the message passing mechanisms, without taking into account the communicating application tasks running in those distributed systems. The main contribution of this paper is to provide an approach for engineering real-time fieldbus systems where the schedulability analysis of the distributed system integrates both the characteristics of the application tasks and the characteristics of the message transactions performed by these tasks. In particular, we address the case of system where the Process-Pascal multitasking language is used to develop P-NET based distributed applications
- Fixed horizon scheduling as an elementary building block for the fixed horizon with reconfigurations, rolling horizon and real time management production scheduling paradigmsPublication . Putnik, Goran; Alves, Cátia; Ávila, Paulo; Ferreira, Luís; Lopes, Nuno; Shah, VaibhavIn this paper we present Fixed Horizon Scheduling as an elementary building block for the Fixed Horizon with Reconfiguration, Rolling Horizon and Real Time Management production scheduling paradigms. An outline of the Fixed Horizon Scheduling as an elementary building block is presented. Also, the outline for the algorithms structure for the three scheduling paradigms based on Fixed Horizon as elementary building block are presented.
- A framework for offloading real-time applications in a distributed environmentPublication . Maia, Cláudio; Silva, Guilherme; Ferreira, Luís; Pinho, Luís Miguel; Nogueira, Luís; Gonçalves, JoelThis work focuses on highly dynamic distributed systems with Quality of Service (QoS) constraints (most importantly real-time constraints). To that purpose, real-time applications may benefit from code offloading techniques, so that parts of the application can be offloaded and executed, as services, by neighbour nodes, which are willing to cooperate in such computations. These applications explicitly state their QoS requirements, which are translated into resource requirements, in order to evaluate the feasibility of accepting other applications in the system.
- A Framework for Simulator Development for Fixed Horizon, Rolling Horizon and Real Time Management Modelling and EvaluationPublication . Putnik, Goran; Alves, Cátia; Ávila, Paulo; Ferreira, Luís; Castro, Helio; Shah, VaibhavThis paper presents a framework for simulator development for fixed horizon, rolling horizon and real time management models for their modelling and evaluation in ubiquitous production networks under conditions of dynamic environments for economic and environmental sustainability.
- A framework for the development of parallel and distributed real-time embedded systemsPublication . Garibay-Martínez, Ricardo; Ferreira, Luís; Pinho, Luís MiguelEmbedded real-time applications increasingly present high computation requirements, which need to be completed within specific deadlines, but that present highly variable patterns, depending on the set of data available in a determined instant. The current trend to provide parallel processing in the embedded domain allows providing higher processing power; however, it does not address the variability in the processing pattern. Dimensioning each device for its worst-case scenario implies lower average utilization, and increased available, but unusable, processing in the overall system. A solution for this problem is to extend the parallel execution of the applications, allowing networked nodes to distribute the workload, on peak situations, to neighbour nodes. In this context, this report proposes a framework to develop parallel and distributed real-time embedded applications, transparently using OpenMP and Message Passing Interface (MPI), within a programming model based on OpenMP. The technical report also devises an integrated timing model, which enables the structured reasoning on the timing behaviour of these hybrid architectures.
- A high performance wireless fieldbus in industrial multimedia-related environmentPublication . Alves, Mário; Tovar, Eduardo; Pacheco, Filipe; Ferreira, Luís; Pereira, Nuno; Machado, Sandra; Brandão, VeríssimoThis paper summarises the most important solutions that have emerged from the work carried out by our team within the framework of the EU (IST-1999-11316) project RFieldbus - High Performance Wireless Fieldbus in Industrial Multimedia-Related Environment. Within this project, Profibus was chosen as the fieldbus platform. Essentially, extensions to the current Profibus standard are being developed in order to provide Profibus with wireless, mobility and industrialmultimedia capabilities. In fact, providing these extensions means fulfilling strong requirements, namely to encompass the communication between wired (currently available) and wireless/mobile devices and to support real-time control traffic and multimedia traffic in the same network.
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