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- Ensino Superior na União Europeia: uma abordagem comparativa entre Estados MembrosPublication . Praça, Lídia GalvãoA construção do Espaço Europeu de Ensino Superior, resultante do acordo de Bolonha, estabeleceu três ciclos de estudo (licenciatura, mestrado e doutoramento) de forma a tornar o ensino mais compatível e comparável na Europa, ao mesmo tempo que estabeleceu o sistema de créditos ECTS (European Credit Transfer and Accumulation System), por forma a facilitar a mobilidade académica e o reconhecimento de qualificações entre os diferentes países (European Education Area, 2025). É neste contexto, que surge este trabalho, cujo principal objetivo é o estudo da evolução do Ensino Superior por estado membro da União Europeia (UE), para o período compreendido entre 2013 e 2023
- Breve análise ao perfil do Ensino Superior em PortugalPublication . Praça, Lídia GalvãoPretende-se com este estudo analisar a evolução do Ensino Superior em Portugal, por ciclo de estudos (licenciatura, mestrado ou doutoramento), nacionalidade do aluno (portuguesa ou estrangeira), género e subsistema de ensino frequentado (público ou privado). Tem por base dados estatísticos publicados pelo INE e Pordata, para o período compreendido entre 2008 e 2024.
- Evaluation of a low-volume unpaved roadPublication . Paula, António Miguel; Minhoto, ManuelLow volume roads complement the national and regional networks, constituting a considerable extension of the existing road network, playing an important social and economic role. In most countries, EBVT networks also integrate unpaved roads and paths, normally connecting more distant and isolated places, often located in protected ecological and agricultural zones. The behavior of these roads is very dependent on the type of soil and its mechanical properties, as well as traffic actions and weather conditions. The evaluation of the mechanical characteristics and bearing capacity of the soils that constitute them is of great importance and is based on the execution of geotechnical characterization tests. A study is presented of an unpaved road, 3.1 km long, located in the natural park of Montesinho, Bragança, which ensures circulation through the park, particularly, the access between two dams that supply water to localities in the region of Bragança. The proper conservation of this unpaved road, by the managing institution (CMB), requires that its structural and functional state be periodically evaluated. Thus, a functional evaluation was carried out, by using an adequate methodology, observing the state of degradation of its road surface and the drainage system, which is of great importance for its integrity. A structural, or geotechnical, assessment was also carried out at points located every 100 meters, based on which the length of the road was subdivided into homogeneous sections. This subdivision was carried out using the accumulated differences method, proposed by the American Association of State Highway and Transportation Officials (AASHTO), based on the results obtained in the following tests: Plate Load, Light Dynamic Penetrometer, Dynamic Load Tests, which include the Light Falling Weight Deflectometer (LFWD)) and dynamic CBR, and the standard CBR test. In the representative points of each homogeneous section, soil samples were extracted with the objective of carrying out the following laboratory tests: granulometric analysis and consistency limits (identification), Proctor Tests and California Bearing Ratio (CBR). It was taken care to ensure that this type of assessment was carried out annually in campaigns before and after winter. From the results analysed, at the level of each homogeneous section, there was a convergence of results between the different types of tests in each evaluation campaign. It was also found that the evaluated parameters varied between different evaluation campaigns, concluding that these vary in time, with the climatic seasons and with the conservation interventions. A study and update of a relationship between the CBR and the Modulus of the soil of subgrade was also carried out, in order to contribute to a better mechanical characterization (E vs CBR) of road foundations, like of the type recommended in the scope of different methodologies for the design of flexible pavements.
- Rainwater harvesting with conventional or green roofs?Publication . Silva, Flora; Calheiros, Cristina; Albuquerque, António; Lopes, Jorge; Geraldes, Ana MariaThe present approach aims to evaluate the technical and financial feasibility of a rainwater harvesting system for an industrial building in Northeast Portugal, considering the existing conventional roof (scenario 1) and the adaptation of a green roof to the existing roof (scenario 2). In this evaluation, the impact of the two scenarios on the water savings of the building was considered. The expected water savings were 64.47% and 59.43% for scenarios 1 and 2, respectively. Therefore, the expected reduction in the annual water bill was €3867.07 + VAT (scenario 1) and €3564.63 + VAT (scenario 2). For scenario 1, considering a reservoir of 70 m3 for non-potable purposes, such as washing the floor of the building and use in industrial machinery, and an initial investment of 41,109.13 € + VAT, the single payback is 11.29 years. The single payback for Scenario 2 largely exceeded the lifetime of the green roof. However, financial incentives could be proposed to implement green roofs in this building typology, as they are considered interesting solutions to reduce the negative externalities of industrial settlements.
- Modelling techniques for the fire performance of empty cavities in LSF wallsPublication . Piloto, Paulo A.G.; Gomes, Stephan; Torres, Leonardo; Couto, Carlos; Vila Real, PauloThree different solution models were used to compare the fire performance of LSF walls with void cavities. The first solution method considers the air-structure interaction in the cavity region. The second solution method considers the existence of interface elements for the radiation heat transfer in the cavity region allowing the bulk temperature prediction. The third solution method considers the convection and radiation in the cavity region with a prescribed bulk temperature from experiments (hybrid). Solution methods 1 and 3 give a smaller root mean square error (RMSE), when compared with solution method 2. Solution method 3 gives a better approximation because can capture the main fire events during fire testing, such as the cracks and fall off.
- Austenitic hollow stainless steel beams at elevated temperatures: experimental and numerical validationPublication . Piloto, Paulo A.G.; Mesquita, Luís M.R.; Cruz, Áureo; Lopes, Nuno; Arrais, Flávio; Vila Real, Paulo
- A new proposal for estimating the temperatures on the steel deck components of composite slabs under firePublication . Balsa, Carlos; Lima, Lídia; Piloto, Paulo A.G.This work aims to improve the estimation of the temperatures on the steel deck under fire. An accurate estimation of these temperatures is crucial to determine the load-bearing capacity (R) of the slab. An analytical method, alternative to the simplified method provided by Eurocode 4, that enables temperature estimation on the steel deck components (web, lower and upper flange), is derived from the numerical results, obtained with a three-dimensional computational model. This new proposal considers the effect of the concrete thickness ℎ1, enables to obtain unbiased temperatures and, contrary to the Eurocode 4 proposal, fits very well the numerical results.
- Accurate 3D numerical models for the fire performance on lsf partition walls under different fire scenariosPublication . Piloto, Paulo A.G.; Silva, Renata; Frizzera, Giovanna; Torres, Leonardo; Couto, Carlos; Vila Real, Paulo; Mesquita, Luís M.R.; Lopes, NunoThis study presents the development and validation of advanced 3D numerical models to analyse the fire performance of non-load-bearing Light Steel Frame (LSF) partition walls under different fire scenarios, specifically the standard ISO 834 and HYDROCARBON fire. Medium-scale experimental fire resistance tests from prior research were used for validation, focusing on LSF walls with and without cavity insulation (external composite insulation). Three computational solution methods were compared and used to predict the fire behaviour of LSF walls with a void cavity. The finite element method was employed for transient thermal analysis with temperature-dependent material properties, including adaptations to simulate material degradation such as gypsum board cracking and rock wool melting under HYDROCARBON fire conditions. Hydrocarbon fires reduced fire resistance by an average of 57% compared to ISO 834 fires for cavity-insulated walls, whereas external insulation configurations showed less reduction.
- Working capital and financial performance in portuguese accommodation companiesPublication . Fernandes, António B. ; Cardim, Sofia; Ferreira, Jessica; Pinto, LígiaPurpose: This study aims to analyse the impact of Working Capital on the Free Cash Flow of Portuguese companies that operate under the Division 55 Accommodation, and that represent the main companies in the tourism sector. Methodology: The research used a sample of 2,227 companies, with a total of 26,689 observations between 2011 and 2023, obtained from the Sistema de Análise de Balanços Ibéricos database. A multiple linear regression was developed based on financial data from companies in Division 55 and 12 research hypotheses were formulated and tested, in order to analyse the impact of different components of working capital in determining the free cash flow of companies in the Accommodation sector. Results: The variation in working capital proved to have a negative and statistically significant impact on the free cash flow of the companies analysed. It was also found that all the variables studied have a significant influence on the model, explaining around 60 per cent of the variation in Free Cash Flow. Research limitations: The study focuses only on a specific sector, which may limit the generalisation of the results to other economic sectors. Originality: This research contributes to the literature by empirically evaluating the relationship between working capital and free cash flow in the Accommodation sector in Portugal, which is a relevant sector for Gross Domestic Product and its companies are characterised by several specificities.
- Tourism in transition: financial sustainability as a compass for resiliencePublication . Fernandes, António B. ; Ferreira, Jessica; Seidi, Fadiba; Cardim, SofiaPurpose: This study aims to analyse the economic and financial sustainability of companies in the tourism sector in Portugal, focusing on Divisions 55 - Accommodation and 56 - Food and Beverage Service Activities, based on the Return on Assets (ROA) indicator, to identify performance differences over time, by firm size and across regions. The methodological choice to use ROA is due to its robustness and the possibility of comparison in longitudinal and cross-sectional evaluations. Methodology: The analysis is based on a sample of 8,735 companies, corresponding to 113,559 observations between 2011 and 2023. The main variable used was Return on Assets (ROA). After checking for the absence of normality and homogeneity of variances, robust statistical methods were applied, namely Welch's ANOVA and the Games-Howell post hoc test using bootstrapping, in order to guarantee reliability in the inferences. Results: The results showed statistically significant differences in the economic and financial sustainability of companies over the years, between companies of different sizes and between regions. Small companies had a higher average ROA than micro, medium and large companies. Regionally, the Algarve stood out for its better performance, unlike the Autonomous Region of the Azores, which recorded the worst average ROA results. Research limitations: The analysis focused exclusively on quantitative financial performance indicators and did not include qualitative variables that could enrich the understanding of the factors that condition sustainability. Additionally, the lack of statistical normality and the heterogeneity of the sample limited the application of conventional parametric tests. Originality: The study contributes to the literature by offering a longitudinal and regional perspective on financial sustainability in the tourism sector in Portugal (Divisions 55 - Accommodation and 56 - Food and Beverage Service Activities), with a robust approach. It also emphasises the role of small businesses as vectors of resilience and the importance of defining public policies that are differentiated according to territorial context.