Browsing by Author "Alves, Ana"
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- Building life cycle applied to refurbishment of a traditional building from Oporto, PortugalPublication . Rodrigues, Fernanda; Matos, Raquel; Alves, Ana; Ribeirinho, Paulo; Rodrigues, HugoBuildings management along with its life cycle is currently an issue that requires a great optimisation considering the high cost associated with the buildings use and due to the operation and maintenance costs. The number of existing buildings needing refurbishment actions justify the need of an intervention model that optimise its service life after the refurbishment process. So, a refurbishment, maintenance and costs planning should be established and guided by value for money principles. The aim of this paper is to analyse the application of Buildings Life Cycle Management (BLCM) to a case study under a refurbishment process, to study the specific solutions and to assess the correspondent service life using the factor method according the ISO 15686 family. With this study, was possible to assess solutions and refurbishment conditions in terms of durability, when compared between the different proposals. In order to improve the case study Building Life Cycle maintenance, in addition, was applied Building Information Modelling (BIM), as BLCM is connected with BIM in order to highlight the importance of their inter-relationship. This study concludes about the most advantageous type of maintenance, how BIM can contributes to BLCM and how can improve maintenance plans. Thus, this study contributes to highlight the importance of preventive maintenance, to promote its implementation and consequently, to use maintenance plans reducing life cycle cost and increasing materials service life.
- Multi-Class Intrusion Detection in Internet of Vehicles: Optimizing Machine Learning Models on Imbalanced DataPublication . Palma, Ágata; Antunes, Mário; Bernardino, Jorge; Alves, AnaThe Internet of Vehicles (IoV) presents complex cybersecurity challenges, particularly against Denial-of-Service (DoS) and spoofing attacks targeting the Controller Area Network (CAN) bus. This study leverages the CICIoV2024 dataset, comprising six distinct classes of benign traffic and various types of attacks, to evaluate advanced machine learning techniques for instrusion detection systems (IDS). The models XGBoost, Random Forest, AdaBoost, Extra Trees, Logistic Regression, and Deep Neural Network were tested under realistic, imbalanced data conditions, ensuring that the evaluation reflects real-world scenarios where benign traffic dominates. Using hyperparameter optimization with Optuna, we achieved significant improvements in detection accuracy and robustness. Ensemble methods such as XGBoost and Random Forest consistently demonstrated superior performance, achieving perfect accuracy and macro-average F1-scores, even when detecting minority attack classes, in contrast to previous results for the CICIoV2024 dataset. The integration of optimized hyperparameter tuning and a broader methodological scope culminated in an IDS framework capable of addressing diverse attack scenarios with exceptional precision.
- Reference values for respiratory muscle strength in portuguese healthy peoplePublication . Alves, Ana; Miranda, Sara; Machado, Ana; Paixão, Cátia; Oliveira, Ana; Rebelo, Patrícia; Cruz, Joana; Jácome, Cristina; Marques, AldaBackground: Maximal inspiratory (MIP) and expiratory pressures (MEP) are measures to assess respiratory muscle strength. Reference values are population-specific and are lacking for the respiratory muscle strength of the Portuguese population. Overcoming this absence is important, to avoid over- or underestimation of such values and to facilitate the identification of Portuguese individuals with respiratory muscle weakness, so tailored interventions can be delivered. Reference values for respiratory muscle strength in portuguese healthy people. Objective: To determine reference values for MIP and MEP in middle aged and older Portuguese healthy people. Methods: A cross-sectional study was conducted in the north and center regions of Portugal. Healthy participants were recruited from community centers. MIP and MEP were assessed using a respiratory pressure gauge (MicroRPM, CareFusion, Kent, United Kingdom). Descriptive statistics were used to determine reference values by age decades (50-59; 60-69; 70-79 and >80 years) and sex. Independent sample t-tests were used to analyse differences between sex in each age decade and one-way ANOVA with Bonferroni-correction to compare age decades. Results: A total of 164 healthy participants were included in this study (67.7±9.7yrs, n=79♂, 28.0±4.8kg/m2). MIP and MEP reference values are shown in table 1. MIP and MEP values were higher in males (92.3±26.3; 139.1±35.2 cmH2O) than in females (78.3±23.4; 104.3±25.6 cmH2O) (p<0.001). MIP mean values were significantly different among age decades (F=5.4; p=0.002), specifically between 50-59 and >80years decades (p=0.01) and between 60-69 and >80years decades (p=0.003). The mean values of MEP were not significantly different across age decades. Conclusion: In Portuguese healthy people, respiratory muscle strength differs between males and females and among age decades. This is part of an ongoing work that will increase the sample size to characterise respiratory muscle strength in the Portuguese healthy population.
- Relationship between 1-minute sit-to-stand and respiratory muscle strength in COPDPublication . Alves, Ana; Miranda, Sara; Machado, Ana; Paixão, Cátia; Oliveira, Ana; Rebelo, Patrícia; Cruz, Joana; Jácome, Cristina; Marques, AldaBackground: It has been suggested that patients with chronic obstructive pulmonary disease (COPD) with respiratory muscle weakness achieve poorer results in exercise capacity tests, namely in the six-minute walk test (6MWT). The 1-minute sit-to-stand test (1-min STST) is simple to perform and a reliable and valid indicator of functional exercise capacity that correlates well with the 6MWT. However, its association with respiratory muscle strength in COPD is poorly studied. Objective: To explore the relationship between the 1-min STST and maximum inspiratory (MIP) and expiratory pressures (MEP) in patients with COPD. Methods: A cross-sectional study was conducted in the center and north regions of Portugal. Outpatients with COPD were recruited from routine pulmonology appointments. The 1-min STST and MIP/MEP were collected and predicted percentages (pp) of MIP/MEP were calculated using the equation set by Neder and colleagues. Correlations between the number of repetitions in the 1-min STST and MIPpp/MEPpp were explored by sex using Spearman coefficient correlation. Results: 376 outpatients with COPD (66.3±10.2y; 76.1%♂; FEV1 61.1±23.4pp; 101.6±8.0% ♂MIPpp; 79.2±5.2% ♀MIPpp; 110.9±8.1% ♂MEPpp; 76.7±6.5% ♀MEPpp) were included in this study. When the correlation was assessed by sex, low positive correlations were found between 1-min STST and MIP/MEPpp in males (r=0.37, p<0.001) (Fig.1). There was no significant correlation between 1-min STST and of MIP/MEPpp in females (p>0.05). Conclusion: 1-min STST correlated significantly with predicted respiratory muscle strength in male patients with COPD. Patients with respiratory muscle impairment seem to have worse functional capacity than those with better MIP and MEP. Thus, respiratory muscle training may play an important role in the improvement of functional capacity in patients with COPD with respiratory muscle weakness.
- RespirArFundo: Um programa de promoção de exercício físico em professores e funcionários em contexto escolar - Estudo quantitativo e qualitativoPublication . Brito, Sara; Morouço, Pedro; Matos, Rui; Alves, Ana; Frontini, Roberta; Silva, Marlene; Antunes, RaulO projeto RespirArFundo, através de uma metodologia mista quantitativa e qualitativa teve como objetivo avaliar o efeito de um programa de intervenção (22 “sessões teórico-práticas”), com realização de diferentes tipos de atividades, para melhorar os níveis de aptidão física, bem-estar e qualidade de vida (QdV) em professores e funcionários de uma escola secundária da região centro de Portugal. Pretendeu-se ainda avaliar os níveis de satisfação dos participantes com o projeto e identificar as principais barreiras e facilitadores à sua participação. A fase de intervenção deste projeto decorreu entre janeiro e junho de 2021. A amostra foi constituída por 26 profissionais da escola (19 professores e 7 funcionários não docentes), sendo na sua maioria (92.3%) do sexo feminino (53.7 ± 5.0 anos). Para a avaliação da aptidão física foram utilizados os testes “levantar e sentar da cadeira”, “levantar, percorrer 2.44m e sentar” e o “teste de preensão manual”. Para a avaliação do bem-estar recorreu-se às escalas PANAS, SWLS e SVS enquanto o WHOQOL-Bref foi utilizado para a avaliação da QdV. Foi ainda realizado um grupo focal. Apóso programa, verificou-se que os participantes melhoraram no teste “levantar e sentar na cadeira” (η2=0.51), em relação ao momento inicial. Para além disso, os participantes revelaram níveis elevados de satisfação com o programa e percecionaram a existência de benefícios físicos e de bem-estar associados ao projeto, adotando hábitos saudáveis. A importância do projeto foi reconhecida pela Direção da escola, tendo sido atribuídas horas específicas para que o projeto continuassea funcionar nos seguintes anos letivos.