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Optimized reinforcement learning for sesource allocation in Vehicular Ad Hoc networks
Get PDFThe vehicular ad hoc networks VANET is an essential part of intelligent transportation systems (ITSs) since it may offer various multimedia services and safety services to pedestrians, passengers, and even drivers. A wireless communication protocol called dedicated short-range communication (DSRC) was created for toll collection systems. Nevertheless, DSRC standards are extremely constrained, necessitating the development of next-generation communication protocols appropriate for VANET. Here, intended to develop an Optimized Reinforcement Learning (ORL) for obtaining resource allocation in VANET. This proposed methodology is developed for achieving resource allocation with efficient data transmission. This proposed approach is utilized to adjust the control channel interval (CCI) and service channel interval (SCI) to empower network performance. Additionally, it is utilized to reduce data collisions and optimize the network’s backoff distribution. The proposed method is a combination of reinforcement learning (RL) and adaptive coati optimization (ACO). The coati optimization mimics the characteristics of coati in natures in which it depends upon the coati escape from predators and hunting and attacking behaviour at various climates.The RL is utilized to obtain an efficient channel access algorithm. In the RL, the Q value is optimally selected by using ACO. Based on this algorithm, the proposed method is utilized to enhance the performance of VANET data transmission by achieving optimal resource allocation. The proposed method is implemented in MATLAB, and performances are evaluated using performance measures. Additionally, to validate the performance of the proposed methodology, it is compared with conventional techniques
As orientações da OCDE em matéria de preços de transferência [artigo de imprensa]
No full textO mundo dos negócios tem vindo adaptar-se, e a formação de grandes grupos económicos é uma realidade no mercado global. Esta reorganização económica evidencia desafios ao nível fiscal, considerando o aumento das transações entre entidades do mesmo grupo. [...
Capacitação em Responsabilidade Social no Ensino Superior: Uma competência transversal essencial
Get PDFEste estudo de caso analisa metodologias pedagógicas que fomentam a competência em responsabilidade social (RS) e sustentabilidade nos estudantes do ensino superior (ES), dado que esta competência contribui para o desenvolvimento de cidadãos socialmente comprometidos. Tendo as Instituições de Ensino Superior (IES) a missão de formar, integralmente os estudantes, a capacitação em RS e sustentabilidade terá impacto na construção de cidadãos solidários em prol de uma sociedade mais justa e mais coesa. Este trabalho assenta em estudos sobre metodologias pedagógicas ativas (e.g., Projectbased Learning (PBL) e Aprendizagem e Serviço (ApS)) que têm como foco a promoção de competências, nomeadamente, em RS e sustentabilidade. Os dados recolhidos, nas entrevistas a três docentes do ES, foram analisados através da técnica de análise de conteúdo. Verifica-se que as práticas pedagógicas que capacitam em RS e sustentabilidade contribuem para a construção de cidadãos socialmente responsáveis, desenvolve seres reflexivos e participativos em que a dimensão humanista norteia as suas ações. Conclui-se da relevância do desenvolvimento de projetos interdisciplinares, no ES, com metodologias PBL e ApS em complementaridade, em contextos sociais reais. Entendese essencial capacitar em RS e sustentabilidade e q u e o t e m a se constitua como área de formação transversal a todos os cursos do ES
High-performance real-time human activity recognition using Machine Learning
Get PDFHuman Activity Recognition (HAR) is a vital technology in domains such as healthcare, fitness, and smart environments. This paper presents an innovative HAR system that leverages machine-learning algorithms deployed on the B-L475E-IOT01A Discovery Kit, a highly efficient microcontroller platform designed for low-power, real-time applications. The system utilizes wearable sensors (accelerometers and gyroscopes) integrated with the kit to enable seamless data acquisition and processing. Our model achieves outstanding performance in classifying dynamic activities, including walking, walking upstairs, and walking downstairs, with high precision and recall, demonstrating its reliability and robustness. However, distinguishing between static activities, such as sitting and standing, remains a challenge, with the model showing a lower recall for sitting due to subtle postural differences. To address these limitations, we implement advanced feature extraction, data augmentation, and sensor fusion techniques, which significantly improve classification accuracy. The ease of use of the B-L475E-IOT01A kit allows for real-time activity classification, validated through the Tera Term interface, making the system ideal for practical applications in wearable devices and embedded systems. The novelty of our approach lies in the seamless integration of real-time processing capabilities with advanced machine-learning techniques, providing immediate, actionable insights. With an overall classification accuracy of 90%, this system demonstrates great potential for deployment in health monitoring, fitness tracking, and eldercare applications. Future work will focus on enhancing the system’s performance in distinguishing static activities and broadening its real-world applicability
Do real estate investment companies profit from house price growth? Evidence from Portugal
No full textThis study aims to study the sensitivity of nonlisted real estate investment companies’ accounting earnings to house prices. This study evaluates whether house price changes determined these companies’ return on equity (ROE) or if other factors influenced the industry’s profitability beyond house price growth
Clima e guerra como desafios da salvaguarda do nosso património [artigo de imprensa]
No full textA Carta de Veneza, carta internacional para a conservação e restauro de monumentos e sítios, 60 anos depois, continua de enorme atualidade nos fundamentos da salvaguarda do património e nos princípios que a sustentam. Os seus conceitos mantêm-se inalteráveis, basilares e cruciais no pensamento da conservação do património, alargados, hoje, nos planos material e imaterial. Os seus valores continuam a ecoar, ano após ano, com rigor e assertividade face às inúmeras necessidades e desafios que comporta a ação de salvaguarda e de preservação de bens tão marcantes nas nossas vidas. [...
The Abbreviated 3-Item Versions of the Satisfaction With Life Scale and the Satisfaction With Love Life Scale
Get PDFThe Satisfaction with Life Scale (SWLS) and the Satisfaction with Love Life Scale (SWLLS) are cognitive measures of subjective well-being. Each scale includes 5 items. The major goals of this work were to analyze the psychometric features and validity of the abbreviated 3-item forms of the Satisfaction with Life Scale (SWLS-3) and the Satisfaction with Love Life Scale (SWLLS-3), as well as the measurement invariance (MI) by gender and age in a Portuguese population. The sample comprised 1,271 participants with an average age of 38 years. Confirmatory factor analyses (CFA) demonstrated that the two-dimensional model of SWLS-3 and of SWLLS-3 presented good fit indices. The reliability was adequate. Furthermore, these scales demonstrated MI across gender and age. The correlations of the 3- and 5-item measures with these well-being measures were very similar. Overall, the 3-item versions of the SWLS-3 and the SWLLS-3 are presented as valid and reliable measurement tools
Inmates’ Mental Health and Violent Outcomes: An Exploratory Study
No full textPerfil de investigadora ainda não criado.Objective: The present study intends to examine (a) the prevalence of mental health problems among male and female detainees and (b) the role of different conditions on various violence-related outcomes among remand prisoners. To advance these primary objectives, the study additionally aims to explore the validity of the Jail Screening Assessment Tool (JSAT), developed to identify mental health problems in jails and prisons. Method: This study included a total of 198 individuals who were in prison awaiting trial between July 2021 and March 2023. Results: This study revealed that JSAT shows good psychometric properties in terms of item sensibility, convergent and discriminant validity, and known-groups validity. Our results showed that, generally, the most prevalent problems were anxiety, depression, and blame. In addition, our findings confirmed that women reported more somatic problems, anxiety, depression, suicide, and motor retardation, while men reported a higher prevalence of blunted affect and motor hyperactivity. Moreover, this study revealed that JSAT dimensions are associated with measures of violent behavior. Our results showed that certain dimensions, such as suspiciousness and motor retardation, were found to predict multiple violence-related outcomes. Conclusions: Overall, this study denoted that JSAT has promising results in different validity and sensibility markers, shedding light on its contribution to understanding the influence of mental health conditions on violent behaviors
Assessing and promoting data fragility in schools: Open questionnaires for auto-evaluation in educational roles
No full textSPADATAS is an Erasmus + that aims to raise awareness on data fragility and enhance data protection of students in academic data management. One of the objectives of the project is to develop tools or instruments for auto-assessment of data protection knowledge and skills. In this manuscript we present different questionnaires designed to assess data fragility and enhance data privacy among educational roles such as teachers, principals, IT admins, and data privacy officers. The tool, developed based on the principles of DigCompEdu, aims to raise awareness about data protection processes, responsible use of digital competence, and the need for acquiring digital skills. By evaluating participants’ perceptions, the tool help to stakeholders address objectives such as analyzing data literacy proficiency, mapping data academic management processes, identifying flaws and gaps in data treatment, and detecting needs for digital skills and competencies. Schools can utilize this tool to assess their digital skills, enhance data literacy, and reinforce privacy and security measures for students’ data, ultimately fostering policy updates for data treatment
The protection of Ukrainian migrants in Portugal: From the International and European Regime to Portuguese Law
Get PDFThe war in Ukraine caused a major humanitarian crisis, leading thousands of civilians to leave the country and seek refuge in third countries. In this perspective, rather than being migrants, the people fleeing this war shall be considered as refugees in accordance with the 1951 Refugee Convention and its 1967 Protocol. Council Directive 2001/55, of July 2001 created a special procedure to deal with a “mass influx” of people in need of international protection. Due to the war in Ukraine, this Directive was triggered by EU Council Decision 2022/382 of 4 March 2022. In this sequence, in response to the need for assistance to and protection of refugees, Portugal presented a plan for their reception, having established a legal regime delimiting criteria for their protection, as well as the scope of temporary protection to be granted under the decree-law 24-B/2022. We propose to analyse the protection regime granted, considering the criteria defined by Public International Law and European Union Law, to assess the convenience, opportunity and sufficiency of the measures implemented before proposing solutions consistent with the humanitarian crisis-situation experienced in Europe, and the reception and integration of these migrants