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Interação entre a política monetária e orçamental
No full textEsta dissertação estuda a coordenação entre política monetária e política orçamental no contexto português, durante o período 2012 a 2024, e o seu impacto na recuperação económica após a crise da dívida soberana da Zona Euro. Esta investigação parte da constatação de que a política monetária na Zona Euro é centralizada pelo Banco Central Europeu, enquanto a política orçamental é descentralizada, sob jurisdição de cada Estado-membro, o que limita a coordenação entre as instituições europeias e os países.
Recorrendo a dados trimestrais obtidos do BCE, Eurostat e AMECO, aplicaram-se modelos econométricos OLS com variáveis de interação e modelos VAR com uma defasagem, complementados por testes de estacionariedade e análise gráfica. Foram testadas três hipóteses: (1) o "Quantitative Easing" foi mais eficaz quando combinado com défices expansionistas; (2) a política monetária convencional tem um impacto limitado em contextos de défice elevado; e (3) a combinação de despesa pública e taxas de juro baixas promove maior crescimento económico.
Os resultados indicam que o défice, em contexto de política monetária expansionista, contribuiu positivamente para o PIB, enquanto a eficácia das taxas de juro foi limitada em períodos de défice elevado. Estas conclusões acrescentam evidência empírica específica para o caso português, enfatizando a importância de uma coordenação para maximizar o impacto das políticas macroeconómicas, e reforça a necessidade de reformas institucionais na Zona Euro para viabilizar essa coordenação.This dissertation analyses the interplay between monetary and fiscal policy in Portugal over the period 2012–2024, assessing its impact on economic recovery in the aftermath of the Eurozone sovereign debt crisis. The study begins from the premise that monetary policy in the Eurozone is centralised under the authority of the European Central Bank, while fiscal policy remains decentralised, under the jurisdiction of individual Member States. This institutional arrangement constrains effective coordination between European institutions and national governments.
Drawing on quarterly data from the ECB, Eurostat, and AMECO, the analysis employs econometric Ordinary Least Squares (OLS) models with interaction terms and Vector Autoregressive (VAR) models with a single lag, complemented by stationarity tests and graphical analysis. Three hypotheses are tested: (1) Quantitative Easing proved more effective when combined with expansionary fiscal deficits; (2) conventional monetary policy exerts a limited impact in periods of high fiscal deficit; and (3) the simultaneous implementation of public spending measures and low interest rates fosters stronger economic growth.
The results indicate that, in a context of expansionary monetary policy, fiscal deficits contributed positively to GDP, whereas the effectiveness of interest rate adjustments was limited during periods of high deficit. These findings provide country-specific empirical evidence for Portugal, underscoring the importance of policy coordination to maximise the effectiveness of macroeconomic measures, and strengthening the case for institutional reforms within the Eurozone to facilitate such coordination
High-precision pose measurement of containers on the transfer platform of the dual-trolley quayside container crane based on machine vision
Get PDFTo address the high-precision measurement requirements for container pose on dual-trolley quayside crane-transfer platforms, this paper proposes a machine vision-based measurement method that resolves the challenges of multi-scale lockhole detection and precision demands caused by complex illumination and perspective deformation in port operational environments. A hardware system comprising fixed cameras and edge computing modules is established, integrated with an adaptive image-enhancement preprocessing algorithm to enhance feature robustness under complex illumination conditions. A multi-scale adaptive frequency object-detection framework is developed based on YOLO11, achieving improved detection accuracy for multi-scale lockhole keypoints in perspective-distortion scenarios ([email protected] reaches 95.1%, 4.7% higher than baseline models) through dynamic balancing of high–low-frequency features and adaptive convolution kernel adjustments. An enhanced EPnP optimization algorithm incorporating lockhole coplanar constraints is proposed, establishing a 2D–3D coordinate transformation model that reduces pose-estimation errors to millimeter level (planar MAE-P = 0.024 m) and sub-angular level (MAE-0 = 0.11°). Experimental results demonstrate that the proposed method outperforms existing solutions in container pose-deviation-detection accuracy, efficiency, and stability, proving to be a feasible measurement approach.info:eu-repo/semantics/publishedVersio
Enhancing maritime supply chain security and efficiency: A review of Zero-Knowledge Proofs in blockchain applications
Get PDFDespite the maritime supply chain being the backbone of global trade, it faces persistent challenges in transparency, fraud prevention, shipment tracking and data privacy. Blockchain technology has emerged as a transformative solution, enhancing trust and traceability within supply chain networks. However, its limitations in data privacy and scalability necessitate advanced privacy-preserving mechanisms. Zero-Knowledge Proofs (ZKP) offers a cryptographic approach to validate data without exposing sensitive information, addressing blockchain’s privacy constraints. This paper reviews the state of the art on current applications of blockchain in maritime supply chain management and explores the integration of ZKP for secure trade document verification, fraud detection, privacy-preserving traceability and regulatory compliance. Additionally, it examines computational overhead, scalability and adoption barriers while proposing future research directions. Implementing ZKP within blockchain-based port operations enables robust governance models, ensuring data verification without revealing confidential details. This approach fosters a secure and privacy-compliant trade environment, enhancing trust and collaboration among stakeholders. By optimising resource allocation and mitigating risks, integrating ZKP can significantly improve maritime supply chain efficiency. Integrating Zero-Knowledge Proofs with blockchain, maritime logistics can achieve a balance between transparency, security and operational efficiency, addressing existing challenges in data privacy and regulatory compliance, improving the sustainability of port operations.info:eu-repo/semantics/publishedVersio
Adaptive resilience in freight: Problem-solving strategies for the unexpected
Get PDFThis study examines how Portuguese freight transport managers address operational disruptions, including delays, vehicle breakdowns, and fluctuating demand. Through eighteen semi-structured interviews with certified managers, the research identifies key challenges and managerial responses. Common disruptions cited were scheduling delays (16 participants), breakdowns (13), and last-minute client requests (10). Managers predominantly relied on adaptive, experience-based strategies - such as real-time rerouting, maintaining backup vehicles, and proactive Client Relationship Management to manage expectations and maintain service quality. Five core problem-solving competencies emerged: adaptability (90%), crisis management (65%), client relationship management (60%), resilience (50%), and strategic planning (45%). While these strengths were notable, the study found limited application of collaborative problem-solving (CoPS) and minimal integration of sustainability practices. Managers cited high costs and insufficient policy support as primary barriers to adopting greener strategies. Technological use was largely limited to basic tools like GPS tracking and digital documentation. More advanced systems were underutilized due to financial and technical constraints. The research aims to (1) identify primary disruption types, (2) evaluate response strategies, (3) assess sustainability integration, and (4) examine the role of technology. This study extends the Dynamic Capabilities and Purchasing and Supply Management (PSM) competency frameworks by showing how managers in small/medium logistics firms rely on context-specific, improvisational approaches to manage disruptions. A new conceptual framework is proposed, linking disruption types, managerial competencies, and moderating factors such as limited resources and sustainability pressures. Policy recommendations include targeted training, digital upskilling, supportive incentives to promote resilience and sustainable innovation.info:eu-repo/semantics/publishedVersio
Electricity use of automation or how to tax robots?
Get PDFWhile automation technologies replace workers in ever more tasks, robots, 3D-printers, and AI require substantial amounts of electricity. How are automation technologies affected by the price of electricity, and how do robot taxes and electricity taxes affect their adoption? To answer these questions, we generalize a standard economic growth model to incorporate automation and electricity use. In addition, we augment the model with electricity taxes and robot taxes and show the mechanisms by which these taxes affect automation. We find that an electricity tax—that is comparatively easy to implement—can serve a similar purpose as a robot tax.info:eu-repo/semantics/publishedVersio
Le militantisme féminin dans le mouvement syndical Portugais: La persistance des inégalités de genre 50 ans après la Révolution des Œillets
Get PDFTendo nascido androcentrado, o movimento sindical nunca foi tão feminizado como é atualmente. No entanto, a militância sindical no feminino continua menos intensa do que a masculina. Apesar de ao longo das cinco décadas decorridas desde o 25 de Abril se terem registado progressos relativamente importantes, as desigualdades de género persistem, remetendo para um duplo processo de segregação, horizontal e vertical, com este último a ter como consequência uma generalizada sub-representação das mulheres nas equipas dirigentes e nas lideranças sindicais, o que torna o sindicalismo menos inclusivo e menos representativo e restringe o carácter democrático das organizações, ao mesmo tempo que contribui para a perpetuação da dominação masculina.info:eu-repo/semantics/publishedVersio
The ‘shades of grey’ in research integrity—Researchers admit to questionable research practices that they do not perceive to be serious
Get PDFResearch misconduct practices like fabrication, falsification and plagiarism (FFP) are serious deviations from good research conduct, which have attracted attention in the literature due to the damage they can bring to science and society. However, less is known about the grey zone of researchers’ behaviours that deviate from responsible research conduct but do not fall under serious research misconduct practices. These are known as questionable research practices (QRPs), and they are believed to pose a no less serious threat to research integrity and science. Despite increasing research on the topic, the extent of the problem in different research fields and contexts is unknown. Using a sample of researchers working in Portuguese universities in six main fields of research (n = 1573), we report on QRPs that researchers admit to and how serious they perceive them to be, and on predictors of engagement in QRPs. We find that QRPs are widespread across all fields of research and seniority levels. Yet, younger, more prolific researchers, and those dismissing the seriousness of QRPs admitted to more QRPs. This suggests that some groups are at higher risk of misconduct and that there is a need for studying the motivations behind more susceptible groups to engage in QRPs.info:eu-repo/semantics/publishedVersio
Relação entre o work-life balance e a performance: O Impacto do trabalho por turnos
No full textO work-life balance (WLB) é um conceito cada vez mais valorizado pelos trabalhadores e pelas organizações, uma vez que se revela essencial para a performance. Com base no Job-Demands and Resourcves Model, desenhou-se um modelo concetual que procurou testar como o stress e o afeto positivo influenciam a performance, considerando o papel mediador do work-life balance. No entanto, o trabalho por turnos, um sistema de trabalho cada vez mais comum no contexto organizacional, pode comprometer essa relação, como tal hipotetizou-se que o trabalho por turnos seria uma condição contextual capaz de influenciar essa relação. Para tal, foi realizado um estudo quantitativo com uma amostra de 231 trabalhadores em Portugal, através de um questionário online. Os resultados demonstraram que o work-life balance medeia a relação entre o stress e a performance, assim como entre o afeto positivo e a performance. Verificou-se ainda que o trabalho por turnos moderou as relações indiretas anteriores de tal forma que (1) a relação entre o stress e a performance através do work-life balance e (2) entre o afeto positivo e a performance através do work-life balance tornou-se mais forte para quem trabalhava por turnos (versus quem tinha horário fixo de trabalho). Os resultados reforçam a importância de as organizações implementarem medidas que promovam o work-life balance, sobretudo em contextos de trabalho por turnos.Work-life balance (WLB) is an increasingly valued concept among both employees and organizations, as it plays a crucial role in enhancing performance. Based on the Job Demands-Resources Model, a conceptual model was developed to examine how stress and positive affect influence performance, considering the mediating role of work-life balance. However, shift work – a work system that is becoming increasingly common in organizational contexts – may compromise this relationship. Therefore, it was hypothesized that shift work would act as a contextual condition capable of moderating these associations. To test this, a quantitative study was conducted with a sample of 231 workers in Portugal, using an online questionnaire. The results revealed that work-life balance mediates the relationship between stress and performance, as well as between positive affect and performance. Additionally, shift work was found to moderate these indirect relationships, such that (1) the relationship between stress and performance through work-life balance and (2) the relationship between positive affect and performance through work-life balance were both stronger for employees working shifts (versus those with fixed working hours). These findings underscore the importance of implementing strategies that promote work-life balance, particularly in shift-based work environments
Addressing teacher occupational health in challenging times: The role of a positive organizational climate in buffering teachers’ burnout
Get PDFTeacher occupational health is a critical issue worldwide that COVID-19 has worsened. While previous research has highlighted the impact of chronic work-related stress and limited personal resources on burnout, much of this research relies on cross-sectional data that do not capture how these effects develop over time. Additionally, the role of positive organizational factors remains underexplored. Our study examined burnout trajectories among 101 Portuguese elementary teachers (94.1% women, M = 46.03 years, 85.6% enrollment rate) over five data collection points spanning the 1st and 2nd COVID-19 waves (2019–2021) and investigated the impact of organizational climate on teacher burnout indicators. Main work-related stressors were identified through an open-ended question. Trajectories of occupational stress and burnout were analyzed using independent ANOVAs, and moderation analyses tested the relationship between organizational climate, occupational stress, and burnout indicators. Results showed a significant drop in perceived personal accomplishment during the first lockdown. Key stressors included greater job demands and more strained interpersonal relationships. Organizational climate significantly moderated the effect of work-related stress on emotional exhaustion, while having a positive main effect on personal accomplishment. This research contributes to a strengthened theoretical understanding of burnout as a dynamic, context-sensitive process, offering new empirical evidence, especially in underrepresented educational systems like Portugal. It emphasizes the importance of addressing contextual factors when working to reduce teacher burnout. Rethinking professional development and workplace relationships is essential for supporting teachers’ occupational health in today’s uncertain educational environments.info:eu-repo/semantics/publishedVersio
O impacto das ONGD na educação para o desenvolvimento
No full textA presente dissertação tem como objetivo compreender o trabalho desenvolvido em Portugal na área da Educação para o Desenvolvimento pelas Organizações Não Governamentais para o Desenvolvimento, respondendo assim à pergunta de partida: Qual o impacto das ONGD na Educação para o Desenvolvimento.
Neste sentido, foi realizada uma análise bibliográfica qualitativa focada na Educação para o Desenvolvimento (ED) a fim de compreender a evolução histórica desde a sua origem, na década de 1970, até à atualidade conjuntamente com uma avaliação dos projetos de ED, financiados pelo Camões – Instituto da Cooperação e da Língua, I. P. (Camões I.P.) entre 2018 e 2022.
Adicionalmente foram realizadas entrevistas a duas pessoas experientes na área da ED com os seguintes objetivos de compreender como é a promoção da ED dentro das ONGD, analisar os objetivos e sustentabilidade dos projetos e analisar o financiamento dos projetos de ED.
Através da análise efetuada por esta dissertação verifica-se que um dos aspetos importantes da ED é a possibilidade de educar as gerações para as questões globais e educar novos ativistas. É de realçar que a ED permite promover valores essenciais, como tolerância, respeito pela diversidade e responsabilidade social. valores estes que para além de enriquecerem a experiência educativa, são fundamentais para a formação de cidadãos éticos e responsáveis. Conclui-se também que o principal desafio que as ONGD enfrentam é o financiamento. Quanto maior a disponibilidade financeira, tanto maior será o impacto positivo da ED.This dissertation aims to understand the work carried out in Portugal in the area of Development Education in Portugal by Non-Governmental Development Organizations, thus answering the starting question: What is the impact of NGDOs on Development Education.
In this sense, a qualitative bibliographic analysis was carried out with a focus on Education for Development (DE) in order to jointly understand the historical evolution from its origins, in the 1970s, to the present. In addition, an assessment was made of DE projects, funded by Camões – Instituto da Cooperação e da Língua, I. P. (Camões I.P.) between 2018 and 2022.
Additionally, interviews were carried out with two experienced experts in the field of DE with the following objectives: understanding how DE is promoted within NGDOs; analyze the objectives and sustainability of projects and; analyze the financing of ED projects.
Through the analysis carried out in this dissertation, it was possible to conclude that one of the important aspects of the importance of DE is the possibility of educating generations on global issues and educating new activists. It should be noted that ED allows us to promote essential values, such as tolerance, respect for diversity and social responsibility., these values, in addition to enriching the educational experience, are also fundamentally important for the formation of ethical and responsible citizens. It is also concluded that the main challenge that NGDOs face is financing. The greater the financial availability, the greater the positive impact of ED would be