Modelação acoplada dos estuários do Tejo e do Sado e padrões de mesoescala associados

Mestrado em Ciências do Mar e das Zonas CosteirasGiven the close proximity between the Tagus and Sado estuaries, it is understandable that these two hydrodynamic systems have their discharges on the same coastal region. Several studies focus on the investigation of the complex circulation at the mouth of Tagus or Sado estuaries, however, the interaction between these two systems is not taken into account and there are no studies which contemplate the interaction between the two estuaries. With this objective, the three-dimensional model Delft3D-Flow was implemented in order to investigate the complex flows in Tagus and Sado estuaries and adjacent shelf. The numerical model was calibrated and validated using sea surface height, currents, salinity and water temperature data, and then applied to research the role of river discharge and wind effects under mesoscale currents and coastal dynamics at open ocean boundaries on the plumes interaction. The chosen period was the winter of 2009-2010. To examine the response of the estuarine plumes to different wind directions, five scenarios of moderate winds were considered blowing from each of the main four compass points, and with the absence of wind. Through the use of two distinct tracers, three different idealized scenarios were chosen: low, moderate and high Tagus and Sado river discharges. The results showed an evidence of estuarine plumes, filaments and mesoscale eddies caused by the interactions between the estuaries and the nearby coastal region. The obtained results also reveal a intrusion caused by the Sado plume in Tagus estuary after a 10-day simulation. This pattern was not observed for Tagus plume. It was also observed that the Sado estuarine water propagates to Tagus estuary in just 36 hours with coastal dynamics, when compared to the mesoscale currents forcing took around 120 hours. In summary, the model application developed in this study contributed to the characterization and understanding of the interaction between Tagus and Sado estuary’s, and in which conditions these occur.Dada a proximidade entre os estuários do Tejo e do Sado, é reconhecido que as descargas destes estuários ocorrem na mesma região costeira. O conhecimento atual relativo à hidrodinâmica dos estuários do Tejo e do Sado resulta maioritariamente da exploração de resultados de modelos numéricos, que descrevem as propriedades físicas e padrões gerados pelas correntes de maré e descargas fluviais. Não obstante, verificou-se que a interação entre estes dois sistemas não é considerada, não havendo esforços no sentido de estudar os dois sistemas simultaneamente, bem como de descrever as relações que partilham e identificar as mútuas influências a nível dinâmico. Com este objetivo, foi implementado o modelo numérico tridimensional Delft3D-Flow, de forma a investigar a dinâmica do estuário do Tejo, do Sado e da região costeira adjacente. O modelo numérico foi calibrado e validado com a altura de maré, correntes, salinidade e temperatura da água, sendo aplicado para a investigação do efeito das descargas fluviais e do efeito do vento na interação das plumas destes estuários. O período escolhido para as simulações foi o Inverno de 2009-2010. Foram impostos dois tipos de forçamentos na fronteira aberta oceânica, um que comtempla as correntes de mesoescala e outro apenas a dinâmica costeira. Foram considerados cinco cenários para ventos moderados nos quatro principais quadrantes e para a ausência deste. Através do uso de dois traçadores distintos, foram escolhidos três cenários idealizados com descargas baixas, moderadas e altas dos rios Tejo e Sado. Os resultados evidenciaram a presença de plumas estuarinas, filamentos e eddies causados pela interação entre os estuários e a região costeira. Os resultados obtidos revelam ainda uma intrusão da pluma estuarina do Sado no estuário do Tejo após descargas fluviais significativas durante dez dias, contudo, este padrão não foi observado na pluma estuarina do Tejo. Foi ainda observado que a água estuarina do Sado se propaga para o estuário do Tejo em apenas 36 horas com apenas a dinâmica costeira, ao passo que com as correntes de mesoescala só se observou a intrusão após 120 horas. Sumariamente, o modelo desenvolvido para este estudo contribuiu para a caracterização e compreensão da interação entre os estuários do Tejo e Sado, e definição das condições em que esta ocorre

The curse of technological race: the red queen effect

Economic prosperity is tied to scientific development, i.e., there is a strong correlation between science, technology and the wealth of nations. We collected data from scientific and technological production of 183 countries of the last thirty years (1974 to 2003) and applied a super-paramagnetic clustering technique on them, finding nations divided in three regimes, distinguished by the interactions between the agents of their National Systems of Innovation (NSI). The identification of these groups allows us to define the dynamical behavior of the thresholds, that grow exponentially and whose growth rate we have calculated. We show that for the period 1974-2003 the threshold between the immature and the developed NSIs increases by an annual rate of 6.6% (per capita). We identify clearly a "Red Queen Effect". Finally we show that the transitions between the regimes are discontinuous, represented by a structural breakthrough. Therefore, the prerequisite to move from regime I to regime II, and then to regime III are structural changes within NSIs.national systems of innovation; super-paramagnetic clustering technique; moving thresholds

Modeling economic growth fuelled by science and technology

This paper suggests a simulation model to investigate how science and technology fuel economic growth. This model is built upon a synthesis of technological capabilities represented by national innovation systems. This paper gathers data of papers and patents for 183 countries between 1999 and 2003, GDP and population for 2003. These data show a strong correlation between science, technology and income. Three simulation exercises are performed. Feeding our algorithm with data for population, patents and scientific papers, we obtain the world income distribution (R=0.99). These results support our conjecture on the role of science and technology as a source of the wealth of nations.simulation models; systems of innovation; economic growth

Matrices of science and technology interactions: implications for development

Scientific and other non-patent references (NPRs) in patents are important tools to analyze interactions between science and technology. This paper organizes a database with 514,894 USPTO patents granted globally in 1974, 1982, 1990, 1998 and 2006. There are 165,762 patents with at least one reference to science and engineering (S&E) literature, and there are 1,375,503 references. In 2006 there are 83 countries with USPTO patent citing S&E literature. Through a lexical analysis 71.1% of this S&E literature is classified by S&E fields. These data underscore the elaboration of global and national tri-dimensional matrices (by OST technological domains, ISI science and engineering fields and number of references). Descriptive statistics investigate how science and technology linkages differ over time across countries and across levels of development. This paper highlights how the existence (or not) of a pattern of structured growth differentiates mature and immature systems of innovation.science and technology linkages, stages of economic development, systems of innovation

Multimodal metadiscourse: analysis of glosses of the definitions and examples of an English dictionary

In this paper, we examine multimodal resources that perform the metadiscursive function of clarifying the content of definitions and examples in the entries of the Collins COBUILD Illustrated Basic Dictionary of American English (2010). The study is based on Kress and van Leeuwen (2006), regarding the multimodal configuration of texts, on Hyland (1998, 2000, 2007, 2017), concerning the concept of metadiscourse, and on Kumpf (2000), Pontes (2010), Pontes and Fechine (2011, 2012), Fechine (2013), Rocha (2016), and Ribeiro and Pontes (2018), who discuss multimodal metadiscourse. We carried out an overview of the various elements that clarify the content of the definitions and examples in the dictionary and observed that, in general, the content is clarified either through verbal text or images. For this reason, we classified such elements as verbal and visual glosses. Then, we selected and analyzed representative samples of each type of gloss. We concluded that verbal and visual resources rework and even expand the text of definitions and examples in order to facilitate their understanding by a user who has limited knowledge of the English language

The visual metadiscourse of the inserts of an English Dictionary

In this article, we investigate the function of colors and images as metadiscursive elements in the composition of the inserts of the Illustrated Basic Dictionary of American English (2010), which is part of the Collins Cobuild series. The study is based on the categories proposed by Kumpf (2000) for the analysis of the visual metadiscourse and the theory of multimodality by Kress and van Leeuwen (2006). We conclude that the visual resources used for the elaboration of the inserts in this dictionary play the role of organizing the contents, guiding the users, attracting their attention and establishing direct communication between the reader and the author.Key words: visual metadiscourse, inserts, dictionary.</p

O metadiscurso visual do material interposto de um dicionário em Língua Inglesa

In this article, we investigate the function of colors and images as metadiscursive elements in the composition of the inserts of the Illustrated Basic Dictionary of American English (2010), which is part of the Collins Cobuild series. The study is based on the categories proposed by Kumpf (2000) for the analysis of the visual metadiscourse and the theory of multimodality by Kress and van Leeuwen (2006). We conclude that the visual resources used for the elaboration of the inserts in this dictionary play the role of organizing the contents, guiding the users, attracting their attention and establishing direct communication between the reader and the author.Key words: visual metadiscourse, inserts, dictionary.Neste artigo, investigamos a função das cores e das imagens como elementos metadiscursivos no material interposto do IllustratedBasic Dictionary of American English (2010), pertencente à série Collins Cobuild. O estudo tem como base as categorias propostas por Kumpf (2000) para análise do metadiscurso visual e a teoria da multimodalidade de Kress e van Leeuwen (2006). Conclui-se que os recursos visuais utilizados para a elaboração do material interposto deste dicionário organizam os conteúdos, guiam o usuário, atraem sua atenção para a leitura da obra e estabelecem uma comunicação direta entre leitor e autor.Palavras-chave: metadiscurso visual, material interposto, dicionário