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Entre a aliança e a adversidade.
Publication . Neves, Bruno Gonçalves
Na segunda metade do século XVII, durante o reinado de Luís XIV, assistiu-se ao investimento e desenvolvimento do porto de Brest como a principal base naval no Atlântico para a Marinha francesa. A sua posição geográfica, bem como as características físicas do território, permitia-lhe constituir-se como base de projeção para uma eventual invasão das ilhas britânicas, mas também como ponto de apoio logístico para uma força naval permanente, capaz de ameaçar o comércio marítimo britânico.
No século XVIII, com a Guerra da Sucessão Espanhola, e sobretudo durante a denominada Guerra dos Sete Anos, o bloqueio naval de Brest constituiu-se como um dos principais pilares da estratégia naval britânica, forçando os navios franceses a manterem-se no porto, permitindo à Royal Navy a iniciativa e o uso do mar, essenciais para garantir a segurança das ilhas britânicas, da navegação e do comércio marítimo. Com o rebentar da guerra contra a França Revolucionária, em 1793, o bloqueio de Brest e o controlo da navegação no canal da Mancha e mares adjacentes às ilhas britânicas voltou a ser uma prioridade para a Royal Navy. A Coroa Portuguesa foi então chamada a colaborar com a Grã-Bretanha, no quadro da aliança luso-britânica, sendo solicitado o reforço das forças navais britânicas no Mediterrâneo, sob o comando do Almirante Hood. Por iniciativa e insistência do seu Ministro da Marinha, D. Martinho de Melo e Castro, a Coroa Portuguesa entendeu que a futura esquadra de auxílio, a
ser constituída pelas principais unidades navais da Armada Portuguesa, deveria antes atuar no Atlântico, bloqueando os portos franceses como Brest e Rochefort, de onde poderiam sair os navios que colocariam em risco o litoral continental português, ilhas atlânticas e, sobretudo, os portos do Brasil, como havia sucedido nos dois anteriores grandes conflitos daquele século. A partir de meados de 1793, até ao início de 1795, os navios portugueses da chamada Esquadra de Auxílio a Inglaterra, ou simplesmente Esquadra do Canal, foram sujeitos às maiores provações, resultantes da constante variação de ventos e frequentes tempestades, obrigando a procurar proteção nos portos e fundeadouros da costa sudoeste britânica. Mas, também aqui encontravam frequentes ameaças, pois fortes correntes, baixios e outros perigos, ou simplesmente o erro ao falhar a correta aproximação a terra, acabavam por provocar a perda de navios por encalhe e naufrágio, como sucedeu com a fragata portuguesa São Rafael, em 31 de agosto de 1794, nos baixios à entrada do Solent, o canal da Ilha de Wight. Com a presente comunicação pretende-se identificar os principais desafios que a navegação no canal da Mancha representava para os navios da esquadra portuguesa, bem como caracterizar a sua ação e opções tomadas de acordo com os mesmos.
Investigation of the operation of a railgun system with laboratory proportion
Publication . Pereira, P. Sampaio; Gatta, Mário; Teodoro, M. Filomena; Springer Nature
In this document it is addressed the basic principles underlying the function ofthe railgun focusing in the electrodynamic questions. It is intended to acquirefamiliarity with this kind of weapon through the critical study of his functionalprinciples. At first glance, the basic principle of operation of a railgun may seem simple in the light of the immediate application of the Lorenz force in aconductor driven by current. However, everything becomes more complicatedin the case of a quick change of the involved parameters (transitional regime),which requires a more thorough analysis of current behavior, electric andmagnetic fields, and all involved materials in the system.
This project also included the construction of two railguns, initially asmaller size one to gain familiarity with the system, and lastly a laboratoryproportion one in which was performed and analyzed a number of tests withdifferent materials and distinct projectile sizes. To better understand theprocess that involve the railgun process, an analysis in the time domain, of thespatial distribution of the electromagnetic field, electrical current and energyflow was performed. In the present paper, we describe the preliminary conceptsabout the studied weapon, the energy flow, complemented by a summary of theexperimental work associated to the construction of the second railgun (inlaboratory proportions) that allowed us to test distinct materials, forms andsizes.
Measuring ESG adoption in investment funds: Evidence from the Portuguese asset management sector
Soares, Ricardo de Moraes e; Nunes, Alexandre Morais; Kaiseler, Ana Catarina; Gariso, Clara Simões
The article observes the evolution of ESG adoption in Portuguese investment funds during the period 2021–2024 in the context of the strengthening of the European Union’s regulatory framework. The objective was to measure the degree of adoption of the principles, the institutional asymmetries, and the temporal dynamics induced by regulation. The study focused on four fund management companies, representing a total of 259 active funds, and employed a composite indicator on a discrete scale [0.3], defined on the basis of five ESG sub-dimensions. A structured content analysis and
descriptive statistics were conducted, allowing an assessment of the mean, median, absolute and relative dispersion, skewness, and kurtosis of the distributions. The results suggest a continuous growth of the average indicator, from 0.75 in 2021 to 2.20 in 2024, accompanied by an increase in the median from 0.80 to 2.70. The standard deviation increased from 0.36 to 0.93, reflecting a greater absolute heterogeneity, while the coefficient of variation decreased from 0.48 to 0.32 between 2021 and 2022 and normalized around 0.41-0.42. The distributions exhibit persistent negative skewness (between −0.27 and −0.73) and negative kurtosis (between −1.85 and −1.70), which suggests an absence of full convergence and persistence of structural asymmetries. The subdimensions showed higher average values compared to those associated with quantitative measurement and the principle of double materiality. The analysis concludes that the inclusion of the metrics has evolved significantly, but asymmetries persist, which attests to the validity of the indicator as an appropriate tool for conducting ESG analyses.
An Exploratory Framework for Measuring the Levels of Adoption of ESG Principles
Soares, Ricardo de Moraes e; Gariso, Clara; Kaizeler, Ana Catarina; Arcanjo, Mariana
The adoption of environmental, social and governance (ESG) criteria in financial markets is currently playing a key role in redefining investment processes, risk management and non-financial reporting by financial funds. Sustainability reporting, especially in the European context, is marked by a strengthening of the regulatory framework and a requirement for increased availability of information. Despite the increasing centrality of ESG principles and the establishment of the concept of double materiality as structural elements of non-financial reporting, there is a methodological gap in terms of the existence
of standardised, systematic, transparent and comparable instruments that enable the measurement of the levels of implementation of ESG metrics in investment funds. The study proposes to develop a possible experimental indicator to measure the levels of adoption of ESG principles in financial funds, based on a documentary analysis of financial statements, sustainability reports and regulatory disclosures by investment fund management companies. The study proposes to develop a possible experimental indicator to measure the levels of adoption of ESG principles in financial funds, based on a documentary analysis of financial statements, sustainability reports and regulatory disclosures by investment fund management companies. The proposed model, the ESG Methodology Adoption Indicator (IAM-ESG), includes five essential dimensions of ESG integration and aims to reflect aspects related to financial investment policy and processes, regulatory compliance, application of the double materiality principle, adoption of quantitative metrics, and quality of governance and non-financial reporting. Ultimately, the indicator provides a ranking of funds and management companies according to their different levels of maturity in terms of ESG principles and promotes institutional and temporal comparability of investment markets. On an experimental basis, the proposal aims to contribute to the literature and discussion of sustainable finance through the development of an ESG instrument that is theoretically grounded, empirically applicable, aligned with the regulatory framework, and relevant to academia, institutions, and practice.