ESTiG - Artigos em Revistas Indexados à WoS/Scopus
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- From a techno-economic towards a socio-technical approach—a review of the influences and policies on home energy renovations’ decisionsPublication . Abreu, Maria Isabel; Pereira, Andreia; Gervásio, Helena; .Over the past decades, the debate on how to encourage energy efficiency in existing homes has been guided by a technic-economic model that has a strong focus on technologies and cost savings, in which human behavior has been devalued to a narrow behavioral economics overview. While this specific area of behavioral science enabled to capture of the dimension of energy renovations as a problem of homeowners’ individual choice, the collective and social aspects of energy efficiency are still largely overlooked on the energy policy agenda. With its emphasis on how social structures interpenetrate individual actions, social sciences offer additional insights that go beyond the identification of barrier-drivers underlying investment choices and also help to identify positive opportunities for renovation within the conditions of domestic and social life. Until recently, comprehensive behavioral aspects and the social dimension of home energy renovation have been ignored in policy initiatives, and the integration of complementary disciplines is only in its early stages. Based on a broad literature review, this paper aims to provide an up-to-date interdisciplinary perspective of the theoretical evolutionary background, which has been the support to gradually redefine and address the problems associated with energy improvements in homes.
- An agent-based approach for implementing asset administration shell type 3Publication . Sakurada, Lucas; De la Prieta, Fernando; Leitão, PauloIndustry 4.0 (I4.0) is driving the digitization of traditional manufacturing systems toward intelligent and adaptable factories, where industrial assets are interconnected and capable of collaborating inside and cross-company to enhance production processes. A key enabler of this transition is the Asset Administration Shell (AAS), a standardized digital representation of an asset that encapsulates all asset-relevant information throughout its lifecycle. The AAS ensures that all assets, regardless of their type or function, can be seamlessly integrated into the I4.0, facilitating interoperability and efficient data exchange across the entire production network. However, traditional AAS solutions, namely AAS Types 1 and 2, cannot address all the requirements of modern industry environments. To overcome these limitations, the AAS Type 3 (proactive) extends beyond the conventional functionalities of traditional AAS by incorporating more sophisticated features, enabling I4.0 components to operate with greater autonomy, intelligence, and collaborative capabilities. While traditional AAS implementations (Types 1 and 2) have been widely studied and adopted, research on AAS Type 3 is still in its early stages, lacking formal specifications and standardized guidelines for its design and implementation. In this context, this article presents an agent-based AAS approach for implementing AAS Type 3, offering readers a clearer, more accessible description of its features and practical applicability while encouraging further research and development in this emerging topic. For this purpose, several experiments were performed to gain a better understanding of its application in industrial scenarios. Additionally, the article discusses the experiences, insights, limitations and future perspectives derived from the design and experimental implementation of the agent-based AAS approach.
- Exposure to occupational risks in a portuguese care-home for elderly people: a case studyPublication . Oliveira, Rui; Fidalgo, Sandra; Cardim, Sofia; .Residential Structures for the Elderly People (care homes) play an essential role in the social response to support aging populations, reflecting the growing rate of aging in Portugal. These services are carried out by people in different, specific professional categories exposed to labour risks that affect the workers' physical, mental, and social health. Analysing and assessing the risks inherent in the various jobs is key to controlling them and preventing accidents and occupational illnesses. This study involves analysing the risks to which workers in a care home are exposed and, consequently, the preventive measures best suited to eliminating and controlling risks. The methodology involves the application of a questionnaire drawn up based on bibliographical research duly adjusted for the different professional categories. Subsequently, through non-participant observation, the existing risks were surveyed and evaluated, with the other sources of information being duly considered. The results show the need for specific training for the organization's employees and the implementation of lesser used preventive measures, which require more significant investment and support for their application in similar care-home institutions.
- An attempt to predict temperature-time histories for large scale compartment fires: a parametric analysisPublication . Hachana, Romaissa; Benarous, Abdallah; Roudane, Mohamed; Piloto, Paulo A.G.The accurate prediction of thermal conditions within compartment fires poses a significant challenge for fire safety engineers. In fact, sprinkler design, exit sceneries, and collapse structure configurations are closely related to the temporal evolution of the temperature inside the compartments. Through a comprehensive review of existing methodologies and standards, this study attempts to contribute for advancing the state of the art in fire dynamics modelling. The work deals with a comparative analysis of various temperature-time formulations proposed in the literature, providing insights into the discrepancies between theoretical models and real-world standards. It investigates the influence of key factors namely, the opening factor, the fuel load density, and the walls effusivity, on temperature histories. The natural fire curve, such as EPFC leads towards real world planning requirements, allows for a more tailored and pragmatic assessment for large-scale compartment fires, compared to the standard curves. The analysis aims, through a case study, to provide designers and architects with a practical way that facilitates early-stage planning and allows for effective fire prevention implementations.
- Institutional trust as a driver of product boycotts in EuropePublication . Baptista, Nuno; Dos-Santos, Maria; Mata, Fernando; Silva, Natacha JesusDespite the significant growth in consumer boycotts, research has devoted insuffi- cient attention to the institutional factors that may motivate consumers to engage in such behaviour. This article aims to address this research gap. The main objective is to analyse the factors that affect consumer boycotts from an institutional sustainabil- ity perspective, by focusing on a specific dimension of institutional sustainability: institutional trust. Information and data came from the 2023 round of the European Social Survey, a cross-national survey covering 25 Countries. The article applies a binomial univariable logit model to test the influence of institutional trust and other potential drivers on boycott decisions and a multivariable binomial logistic regres- sion to explore possible interrelationship between independent variables. The results confirm that boycotts are affected by institutional trust and other factors including demographic and socio-economic characteristics of the consumers, consumers’ per- ception of ICT, satisfaction with public institutions, and consumers’ evaluation of personal well-being. This article contributes to political consumerism literature by focusing on the impact of institutional trust in boycotting behaviour. This relation- ship is underexplored in existing literature, since most literature researches con- sumer boycotts from a triple-bottom perspective and neglects the effects of the insti- tutional dimension of sustainability in consumer behaviour. The article brings new insights into the motivations of consumers at the political and institutional levels and opens new directions for future research to explore institutional sustainability related to the good practices of governance.
- Fire after earthquake assessment of 3D reinforced concrete structuresPublication . Ismail Haouach; Abdelhak Kada; Belkacem Lamri; Piloto, Paulo A.G.Despite that, an earthquake’s occurrence can lead to dramatic effects with significant damage in urban areas, including human and material losses. Fire after an earthquake amplifies the overall impact and becomes a catastrophic event. Most constructions in Algeria are made of reinforced concrete, and current regulations overlook fires after earthquakes. Structural designs are inadequate to handle such events. This study aims to investigate the behaviour of 3D reinforced concrete frames, as part of a residential building, designed according to internal codes, CBA93 and RPA99 v2003. This 3D RC structure is exposed to several load levels of its vertical load bearing capacity. The structural system is assumed to undergo seismic scenarios characterised by various levels of story drift and damage level types. The structure is then exposed to the standard fire ISO834 model. Numerical investigations are carried out for thermo-mechanical analysis using the finite element software ANSYS, taking into account geometric and material non-linearities. Results highlight the significant impact of vertical loads, story drifts, fire scenarios, and structural damage on a building’s response to fire following an earthquake. These factors collectively influence the collapse probabilities, underlining the importance of holistic risk assessment in structural design.
- Insulation strategies to enhance fire resistance in composite slabs with reduced carbon emissionsPublication . Ribeiro, O.G.N.; Piloto, Paulo A.G.; Gidrão, G.D.M.S.Composite slabs have gained popularity in modern high-rise construction due to their superior load-bearing capacity and reduced self-weight. The vulnerability of the unprotected steel deck under fire conditions poses serious challenges, as the rapid reduction in steel strength and stiffness can compromise structural resistance and accelerate fire spread. This study presents a comprehensive numerical simulation to assess the fire behaviour of a novel composite slab and a new proposal for a simplified method. Three insulation techniques are investigated: a steel shield for the thinner part, a steel shield with the cavity filled with mineral wool, and a mineral wool plate applied from below. The simplified method is proposed to evaluate the fire resistance using new empirical coefficients, recalibrated within the framework of the prEN 1994-1-2 to allow for precise temperature predictions in steel components under standard fire. The numerical model, validated against experimental results, shows that the steel shield insulation extends the time to reach critical temperatures by approximately 25%. In contrast, mineral wool insulation proved to be substantially more effective by reducing temperatures in the UPPER 2 region by up to 89% compared to uninsulated slabs, after 60 min of fire exposure. This significant temperature reduction increases the load-bearing capacity during 60 min of fire exposure by 29%, also resulting in a potential reduction of approximately 22% in carbon emissions. The findings underscore and highlight the potential of these insulation systems to enhance the overall safety and resilience of composite slabs under fire, offering valuable insights for structural fire design.
- An AI-driven Ukrainian history web platformPublication . Kolomiets, Valentyna; Oliveira, Pedro Filipe; Matos, PauloThe AI-driven Ukrainian History web platform offers an innovative way for users to engage with the nation’s rich history. By integrating artificial intelligence, natural language processing (NLP), and geospatial analysis, it presents historical events, significant locations, and notable figures in an interactive and visually engaging format. The platform systematically gathers historical data using tools like Scrapy for web scraping and Tesseract OCR for digitizing scanned documents. While noisy or degraded documents may affect accuracy, the availability of high-quality sources ensures reliable data extraction. Fine-tuned NLP models, including transformers like BERT and RoBERTa, process the data to identify and categorize key entities such as dates, locations, and names of historical figures. Contextual summarization ensures the extracted information is both accurate and easy to understand. Geospatial data is managed with PostGIS, an extension of PostgreSQL, and visualized using Leaflet.js. An interactive map interface enables users to explore events by location and time period, with filters for categories like political milestones or cultural events. The backend, built on PostgreSQL, ensures scalability and performance, while development in Visual Studio Code streamlined integration across components. This platform not only preserves Ukraine’s cultural heritage but also demonstrates the potential of modern technology to transform historical education, offering an intuitive way to connect with the past and explore its influence on Ukraine’s landscape and culture.
- Toward greener mortars with wastewater sludge as cement replacementPublication . Martins, Ramiro; Pietrobelli, JulianaThe cement industry significantly impacts environmental issues, leading to growing demand and research into developing alternatives that result in more environmentally friendly building materials. This research investigates the potential of using sludge from the Bragança Wastewater Treatment Plant (WWTP) as a partial substitute for cement in the formulation of mortar, offering a more eco-friendly solution while promoting waste reutilization. The sludge was prepared using five different methods to evaluate this possibility. M1 was oven-dried, M2 and M3 were sun-dried, M4 was incinerated in a muffle furnace, and M5 was pyrolyzed. Compression tests were carried out to evaluate the mechanical strength of the mortar. Different mixtures were formulated and analyzed, and the M3 specimen containing 7% sludge, showed the highest strength, outperforming the control mortar and those with M1, M2, and M4 sludge preparations, which displayed similar results. On the other hand, the mixture subjected to the pyrolysis treatment (M5) showed the least satisfactory results in terms of strength, even lower than those obtained for the control mortar. Considering the environmental perspective and the pressing need to move towards a circular economy, evaluating the associated energy consumption and mechanical performance is essential. The findings indicated that partial substitution of cement with treated sludge led to a noticeable decrease in energy demand, particularly when low-energy processes like solar drying were employed. It is important to highlight that all the modified mortars, following different methods, were shown to comply with the EN 998-1:2018 standard for compressive strength, which attests to their viability for practical applications. The incorporation of WWTP sludge in mortar production not only reduces cement consumption but also minimises the environmental impacts associated with this industry. At the same time, it contributes to sustainable waste management and economic valorization. The study highlights the feasibility of using mortars incorporating sludge as a cost-effective alternative that also plays a role in mitigating environmental issues. Further studies should assess long-term durability and potential environmental trade-offs, in order to clarify the practical impact of this strategy in actual construction scenarios.
- Tracking urban impacto n the Fervença river via water quality indexPublication . Martins, Ramiro; Pietrobelli, JulianaWater quality is crucial for the survival of living organisms and their environment. The Water Quality Index (WQI) is commonly used to monitor and minimize pollution. This study utilized The WQI was used to evaluate the water quality of the Fervença River in Bragança, Portugal, from January to June 2022. Water samples were collected monthly at five locations along the river. The WQI, which is based on physical, chemical, and biological parameters, provides a comprehensive numerical assessment, ranging from 0 to 100. In general, points 1-4 exhibited a good WQI and showed similar results. However, at point 5, reduced WQI values were consistently observed in all sampling campaigns, indicating a likely connection with discharge from the nearby wastewater treatment plant. The winter season, which is typically characterized by higher rainfall in the region, experienced severe drought during the study period. Consequently, the influence of rainfall on the WQI parameters could not be evaluated as expected, particularly from January to March. Comparing the obtained results, it is evident that as the Fervença River flows through the city of Bragança, the water quality indices decrease in most campaigns, particularly after Point 5. This finding highlights the negative influence of cities on the river water quality. This study highlights the importance of assessing water quality. Points 1 to 4 demonstrated good water quality, whereas point 5 showed reduced quality, linked to the wastewater treatment plant. Drought and city influence affect river water quality, which is crucial for the survival of living organisms and their environments.