IPS - ESTS – DEM - Artigos científicos
URI permanente para esta coleção:
Navegar
Entradas recentes
- Designing strategic scenarios for the digital transitionPublication . Alcácer, Vítor; Tenera, Alexandra; Araújo, Francisco; Carvalho, Helena; Cruz-Machado, VirgílioStrategic scenarios support decision-making under uncertainty; however, existing Industry 4.0 (I4.0) research predominantly adopts technological perspectives and does not provide methodologies that integrate risk man-agement into scenario development. This study addresses this gap by proposing a methodology for developing strategic scenarios for I4.0 adoption based on risk assessment and risk appetite. Following a Design Science Re-search approach, the study includes a systematic literature review (20 studies) to examine existing scenario development approaches in I4.0, which did not identify any methodologies incorporating risk management. This is complemented by a qualitative case study involving 15 experts from industrial and academic contexts. A structured risk analysis identified 35 risks across 9 categories, enabling the prioritization of key factors influencing digital transformation. The study results in the development of a validated methodological framework and four strategic scenarios derived from the interaction between risk levels and organizational risk appetite. The findings demonstrate how integrating risk management into scenario planning enhances strategic decision-making under uncertainty. This study contributes by addressing a critical gap in risk-based scenario methodologies for I4.0 and by proposing a novel framework that integrates risk management into strategic scenario development.
- Improving information flow and decision-Making in maintenance management through BPMN–CMMS integration: a case study in the energy sectorPublication . Mendes, David; Alcácer, Vítor; Terradillos, Elena; Costa, Olga; Ferreira, Rui; Navas, Helena V. G.; Matias, JoãoMaintenance management increasingly depends on effective information flow and coordination between internal teams and external service providers. This study investigates the use of Business Process Model and Notation (BPMN) to support the formalization of Computerized Maintenance Management System (CMMS) workflows and improve transparency, decision-making, and interorganizational coordination. A single case study was conducted in the maintenance department of an electricity distribution company characterized by tacit knowledge, informal communication practices, and limited process formalization. Existing corrective maintenance workflows were analyzed and modeled using BPMN to identify inefficiencies, decision points, and opportunities for improvement. The proposed BPMN models were aligned with CMMS operational states associated with anomaly management and work-order execution processes and supported by a procedural manual. Results obtained during a three-month observation period suggest reductions in training time, email communications, and dependence on individual decision-makers, together with increased use of CMMS workflow functionalities and improved process traceability. These findings provide preliminary evidence, derived from operational indicators within a single case study, that BPMN-supported process formalization may contribute to workflow standardization, operational clarity, and knowledge management in maintenance-intensive environments. Given the single-case design and limited observation period, the results should be interpreted as context-specific and not directly generalizable to the broader energy sector.
- Wearable technologies in occupational safety and health: a systematic review and a human-centered implementation modelPublication . Mendes, David; Terradillos, Elena; Navas, Helena V. G.; Costa, Olga; Matias, João; Soares, VanessaWearable technologies have emerged as promising tools for supporting Occupational Safety and Health through continuous and multimodal monitoring of physiological, biomechanical, and environmental risk factors. However, evidence regarding their real-world effectiveness and implementation remains fragmented. This study presents a systematic literature review conducted in accordance with PRISMA 2020 guidelines, synthesizing evidence from 60 studies addressing wearable-based monitoring, assessment, and intervention in occupational contexts. The review examines the types of technologies applied, the risks and functions addressed, the evidence on effectiveness, the evaluation metrics used, and the main barriers affecting implementation. The findings show that wearable technologies are mainly applied to ergonomic, physiological, environmental, and critical-event risks, using devices such as inertial sensors, biosensors, smart personal protective equipment, and exoskeletons. While the evidence indicates strong potential for real-time monitoring, risk detection, and data-informed decision-making, most studies rely on controlled or short-term evaluations, and consistent evidence of sustained accident reduction remains limited. The results also highlight technical, organizational, ethical, and human-related barriers, including usability, interoperability, privacy concerns, worker acceptance, and data governance. Based on this synthesis, a conceptual human-centered implementation model is proposed to support responsible and context-sensitive adoption.
- The effect of occupancy and environmental physical variables on classrooms’ natural ventilation: a path modeling approachPublication . Duarte, Rogério; Rodrigues, António Moret; Pimentel, Fernando; Gomes, Maria da GlóriaIn this paper, we use a path model to study natural ventilation in classrooms and research the link between air change rate, occupancy, and both outdoor and indoor physical variables. In general, the path model is derived from the building physics and occupant behavioral considerations via structural equation modeling (SEM), and allows for the use of continuous observable and unobservable factors. The latter are often employed in behavioral and social sciences to represent personal and group attributes. The path model is validated with data gathered during two consecutive academic years from four classrooms of a Portuguese school. The results confirm indoor and outdoor air temperature as major drivers of classroom ventilation, with standardized total path coefficients of approximately 0.55. Solar energy, precipitation, and occupancy are also significant drivers of classroom ventilation, with standardized total path coefficients of 0.24, −0.18, and 0.17, respectively. These results contribute to our understanding of the relative importance of occupancy as well as to identifying the most relevant environmental determinants of natural classroom ventilation. In spite of the statistical significance of the path model as a whole and its detailed causal relationships (direct, indirect, and feedback), only 58% of classroom ventilation variance is explained by the selected input variables. Because naturally ventilated classrooms depend significantly on occupants’ interactions with the built environment, i.e., opening/closing windows and blinds, extending path modeling to include additional personal and context-related drivers of occupants’ behavior would allow for further insights into the complex multi-domain topic of natural classroom ventilation.
- Gestão de segurança e saúde no trabalho em projetosPublication . Costa, Olga; Didelet, Filipe
- Análise do processo de gestão de projetos: um estudo de caso no setor da metalomecânicaPublication . Condeixa, Rui; Costa, Olga
- Legislação de segurança contra incêndios: aplicação em edifícios anteriores ao ano de 2008Publication . Gomes, H.; Costa, Olga
- Applying computational fluid dynamics in the development of smart ripening rooms for traditional cheesesPublication . Alvarenga, Nuno; Martins, João; Caeiro, José; Garcia, João; Passáro, João; Coelho, Luis Manuel Rodrigues; Santos, Maria Teresa; Lampreia, Célia; Martins, António; Dias, JoãoTraditional ewe’s cheese producers face certain challenges caused by fluctuating envi- ronmental parameters inside the ripening room, which lead to lack of homogeneity in the final product. The present research discusses the application of computer fluid dynamics for simulating the distribution of environmental parameters, predicting the airflow pattern, and identifying critical areas where such parameters could cause reduced cheese quality. A new monitoring system was developed including presence sensors, temperature and humidity dataloggers, pneumatic actua- tors, microcontrollers, and microcomputers connected remotely for control, data visualization, and processing. The validation of the computer simulation and monitoring system was made with a batch of 40 ewe’s cheeses distributed in three different zones inside a prototype ripening room and ripened for 35 days. At 35 days, a physical, chemical, and microbiological characterization of cheeses was made for evaluation of the influence of environmental conditions on cheese quality. The comparison between simulated and local measurements showed close agreement, especially concerning air velocity inside the stacks of cheese. The results of Pearson’s correlation analysis and PCA concluded that temperature affected the appearance of the rind, hardness, number and area occupied by holes. Humidity affected aw and mFeret. Air velocity affected pH and the circularity of gas holes.
- Latent thermal energy storage application in a residential building at a mediterranean climatePublication . Coelho, Luis Manuel Rodrigues; Koukou, Maria K.; Dogkas, George; Konstantaras, John; Vrachopoulos, Michail Gr.; Rebola, Amândio; Benou, Anastasia; Choropanitis, John; Karytsas, Constantine; Sourkounis, Constantinos; Chrysanthou, ZenonAn innovative thermal energy storage system (TESSe2b) was retrofitted in a residential building in Cyprus with a typical Mediterranean climate. The system comprises flat-plate solar collectors, thermal energy storage tanks filled with organic phase change material, a geothermal installation consisting of borehole heat exchangers with and without phase change material and a ground source heat pump, an advanced self-learning control system, backup devices and several other auxiliary components. The thermal energy storage tanks cover the building’s needs at certain temperature ranges (10–17 ◦C for cooling, 38–45 ◦C for heating and 50–60 ◦C for domestic hot water). A performance evaluation was conducted by comparing the TESSe2b system with the existing conventional heating and cooling system. The systems were simulated using commercial software, and the performance of the systems and the building’s energy needs were calculated. Based on the energy quantities, an economic analysis followed. The equivalent annual primary energy consumption with the conventional system resulted in being 43335 kWh, while for the storage system, it was only 8398 kWh. The payback period for the storage system was calculated to be equal to 9.76 years. The operation of the installed storage system provided data for calculations of the seasonal performance factor and storage performance. The seasonal performance factor values were very high during June, July and August, since the TESSe2b system works very efficiently in cooling mode due to the very high temperatures that dominate in Cyprus. The measured stored thermal energy for cooling, heating and domestic hot water resulted in being 14.5, 21.9 and 6.2 kWh, respectively. Moreover, the total volume of the phase change material thermal energy storage tanks for heating and domestic hot water was calculated to be roughly several times smaller than the volume of a tank with water as a storage medium.