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Mestrado em Análise Financeira Submitted by Filomena Borba (fmborba@iscal.ipl.pt) on 2021-11-12T12:16:50Z No. of bitstreams: 1 Documento Final_Revisão_Dissertacao Joao Batista_ ABR_2021.pdf: 4083289 bytes, checksum: 006fbcc1d1e926d471cfe886b5447155 (MD5) Made available in DSpace on 2021-11-12T12:16:51Z (GMT). No. of bitstreams: 1 Documento Final_Revisão_Dissertacao Joao Batista_ ABR_2021.pdf: 4083289 bytes, checksum: 006fbcc1d1e926d471cfe886b5447155 (MD5) Previous issue date: 2020-11 info:eu-repo/semantics/publishedVersion

Extreme meteorological events have had devastating consequences all over the world throughout the ages. In this study, we look into the floods at the mouth of the Douro River (Porto, Portugal) in the eighteenth century to expand the data series of floods in Northern Portugal. Information was gathered mostly from documentary narrative sources, either individual or institutional (administrative and ecclesiastic), some of which include reports of Pro Serenitate ceremonies. A study by the priest Rebelo Costa (1789) and the memories of the merchant Ignacio Henckell from 1717 to 1800 stand out among the individual sources. We concluded that there was great interannual variability in the occurrence of the 54 recorded floods, the highest number of which occurred in the 1780s. The “catastrophic” floods were recorded in 1727, 1739, 1769, 1774, 1777, 1788 and 1798, four of which are studied in detail in this paper. The greatest number of flood events took place in winter and autumn, and most of them lasted between 1 and 3 days. An analysis of the description of the floods, their impacts and the associated meteorological causes was carried out. In most cases, the frontal activity associated with Atlantic cyclonic systems was the cause of positive precipitation anomalies in NW Iberia. The great variability in heavy precipitation was confirmed by the new data. However, hardly any temporal simultaneity was found with other case studies in Southern Europe, except for Spain, especially several localities of Galicia and the mid Douro Valley (Zamora).

There are concerns that recent climate change is altering the frequency and magnitude of river floods in an unprecedented way. Historical studies have identified flood-rich periods in the past half millennium in various regions of Europe. However, because of the low temporal resolution of existing datasets and the relatively low number of series, it has remained unclear whether Europe is currently in a flood-rich period from a long-term perspective. Here we analyse how recent decades compare with the flood history of Europe, using a new database composed of more than 100 high-resolution (sub-annual) historical flood series based on documentary evidence covering all major regions of Europe. We show that the past three decades were among the most flood-rich periods in Europe in the past 500 years, and that this period differs from other flood-rich periods in terms of its extent, air temperatures and flood seasonality. We identified nine flood-rich periods and associated regions. Among the periods richest in floods are 1560–1580 (western and central Europe), 1760–1800 (most of Europe), 1840–1870 (western and southern Europe) and 1990–2016 (western and central Europe). In most parts of Europe, previous flood-rich periods occurred during cooler-than-usual phases, but the current flood-rich period has been much warmer. Flood seasonality is also more pronounced in the recent period. For example, during previous flood and interflood periods, 41 per cent and 42 per cent of central European floods occurred in summer, respectively, compared with 55 per cent of floods in the recent period. The exceptional nature of the present-day flood-rich period calls for process-based tools for flood-risk assessment that capture the physical mechanisms involved, and management strategies that can incorporate the recent changes in risk., This work was supported by the ERC Advanced Grant ‘FloodChange’ project (no. 291152), the Horizon 2020 ETN ‘System Risk’ project (no. 676027), the DFG project FOR 2416, the FWF projects I 3174 and W1219-N22, the Spanish Agency of Science and FEDER/UE projects CGL2016-75475/R, CGL2017-86839-C3-1-R, CGL2016-75996-R and CTM2017-83655-C2-2-R, the ICREA Academia programme, and project CZ.02.1.01/0.0/0.0/16_019/0000797, Ministry of Education, Youth and Sports of the Czech Republic.

Flood historical records are important to place current flooding events into a long-term perspective. With these data sets it is possible to identify patterns in past recent floods and use these to characterize and model future floods. In what concerns to Portugal, some studies had already used some documentary evidence in order to reconstruct flood events, in particular centered in the year 1786 that was the rainiest in Portugal, triggering floods in northwestern and central Portugal, followed by a extremely wet and rainfall 1788 year that caused floods along the largest Iberian rivers: Douro, Mondego and Tagus. However, very little is known about the characteristics of these events prior to the beginning of regular meteorological/hydrological observations (late 19th century in Portugal).Within this framework, we aim to reconstruct a high-resolution history of floods occurred on the estuary of the Douro River (near the city of Porto, Portugal, Iberian’ Northwest) during the 19th century. The Douro River is the third-longest river in the Iberian Peninsula (after the Tagus and the Ebro rivers) and it drains an area of 97.600 square kilometers (the most largely in the Iberian Peninsula). To achieve our main aim, early instrumental observations and documentary evidence from multiple archival sources were collected. Further, the flooding archive was used to make a serial analysis of the years of floods, their chronological distribution, frequency, duration and intensity, associated with meteorological phenomena and their impacts.

Dadas as diferenças no que tange a restritividade da regulação ambiental entre o Brasil e os países da OCDE, este estudo teve por objetivo principal analisar os efeitos exercidos pela regulação ambiental praticada pela OCDE sobre as exportações de grãos brasileiros, à luz da hipótese de pollution haven e por meio do modelo gravitacional. Os resultados mostraram que a regulação ambiental mais restritiva praticada pelos países da OCDE tende a intensificar a exportação brasileira dos grãos considerados neste estudo, avaliando as diferentes categorias de política ambiental. Tais resultados vão de encontro às demandas internacionais com relação ao avanço da regulação ambiental dos países. Salienta-se que apesar de a regulação brasileira possuir destaque quanto ao seu desenvolvimento e pelo grau de especificidade com que trata os diversos problemas ambientais e manejo dos recursos naturais, esta ainda é ineficiente no combate aos efeitos das atividades produtivas sobre o meio ambiente.

The mutation score is an important measure to evaluate the quality of the test cases. It is obtained by executing a lot of mutant programs generated by a set of operators. A common problem, however, is that some operators can generate unnecessary and redundant mutants. Because of this, different strategies were proposed to find a set of operators that generates a reduced number of mutants without decreasing the mutation score. However, the operator selection, in practice, may include real constraints and is dependent on diverse factors besides the number of mutants and score, such as: number of test data, execution time, number of revealed faults, number of equivalent mutants, etc. In fact this is a multi-objective problem, which does not have a single solution. Different set of operators exist for multiple objectives to be satisfied, and some restrictions can be used to choose among the existing sets. To make this choice possible, in this paper, we introduce a multi-objective strategy. We investigate three multi-objective algorithms and introduce a procedure to establish a set of operators to prioritize mutation score. Better results are obtained in comparison with traditional strategies.

In the context of object-oriented software, a common problem is the determination of test orders for the integration test of classes, known as the class integration and test order (CITO) problem. The existing approaches, based on graphs, usually generate solutions that are sub-optimal, and do not consider the different factors and measures that can affect the construction of stubs. To overcome this limitation, solutions based on genetic algorithms (GA) have presented promising results. However, the determination of a cost function, which is able to generate the best solution, is not always a trivial task, mainly for complex systems. Therefore, to better represent the CITO problem, we introduce, in this paper, a multi-objective optimization approach, to generate a set of good solutions that achieve a balanced compromise between the different measures (objectives). Three different multi-objective optimization algorithms (MOA) were implemented: Pareto ant colony, multi-objective Tabu search and non-dominated sorting GA. The approach is applied to real programs and the obtained results allow comparison with the simple GA approach and evaluation of the different MOA.

This article explores the various place-names given to the geographic localities in the South Atlantic by European cartographers in the 16th and 17th centuries. Despite of the fact that representation of continental space seem to have been more common in mapmaking at the time than the depiction of oceans and seas, oceanic waters often received particular names - regional seas - depending on the coastline in combination to the classical names. A series of connections can be established between this fact and the process of consolidation of slave trading and competition between empires. O artigo explora as diferentes designações toponímicas que o espaço geográfico situado no Atlântico sul recebeu na cartografia européia dos séculos XVI e XVII. Nela, a representação do espaço continental era mais comum do que o registro dos espaços marítimos, frequentemente denominados por designações particulares - mares regionais -, atribuídas segundo a linha da costa. Uma série de conexões podem ser estabelecidas com o processo de consolidação do tráfico negreiro e a concorrência interimperial.

The final stage of the Little Ice Age in Europe was characterized by strong climatic variability. New documentary sources containing information referring to weather and climate are used in this study to reconstruct and to describe climate conditions in Portugal during the 18th century, mainly in the 1780s. Indexation of documentary data concerning hydric and thermal conditions was based on C. Pfister’s methodology and early instrumental data (1780s and 1790s) were used to verify the reconstruction. Precipitation and temperature were highly variable throughout the 18th century: an alternation of extremely hot to extremely cold months was found. Very cold years occurred mostly in the first 2 decades of the 18th century, but several other cold winters were also detected. Precipitation information is far more frequent than for temperature, and allowed yearly and seasonal indexations. The highest variability was detected in the 1730s and the 1780s. The early 1780s were very dry: during the winter and spring of 1781 and the spring of 1782 several drought episodes occurred, as confirmed by ‘pro-pluvia’ rogations. In contrast, heavy precipitation prevailed from 1784 onwards. The year 1786 was the rainiest in Portugal, triggering floods in northwestern and central Portugal. The year of 1788 was extremely wet and rainfall caused floods along the largest rivers: Douro, Mondego and Tagus. A storm that struck north - western Iberia between 23 and 24 February 1788 is analyzed in detail KLIMHIST: Reconstruction and model simulations of past climate in Portugal using documentary and early instrumental sources (17th-19th century) (PTDC/AAC-CLI/119078/2010)

Transgenic maize was approved in Brazil in 2008/2009. In 2012, it occupied 73% of the country maize growing area. This high adoption rate confirms studies indicating that technology use has been the major driving force in Brazilian agriculture. Maize seed market in the world has been a concentrated sector. Although, when this sector is associated with transgenesis, this concentration increases sharply. In one side, there is the idea that companies can benefit from gains of scale and complementarities to maximize their efficiency in research and development (R&D). On the other side, this concentration may allow the exercise of "market power" by dominant companies. The objective of this study is to analyze the impacts of the adoption of transgenic technology in the arrangements of maize breeding programs and seed production sector in Brazil. A critical analysis of the situation of the breeding programs that do not have this technology is made. A tecnologia de transgênicos em milho no Brasil foi liberada em 2008/2009 e em 2012 ocupou 73% da área de milho. Esta alta taxa de adoção confirma estudos que indicam que a opção por uso de tecnologia tem sido o principal fator do desenvolvimento da agricultura nacional. O mercado de sementes de milho no mundo em geral é concentrado, mas a transgenia ampliou esta concentração. De um lado, há a ideia que as empresas podem se beneficiar dos ganhos de escala e complementaridades para maximizar sua eficiência de Pesquisa e Desenvolvimento. De outro, esta concentração pode permitir o exercício do chamado "poder de mercado" pelas empresas dominantes. O objetivo deste artigo foi analisar os impactos da adoção desta tecnologia no arranjo dos programas de melhoramento e no setor brasileiro de produção de sementes. Uma análise crítica da situação dos programas de melhoramento que não detêm esta tecnologia é feita.

Resumo: No desenvolvimento de software frequentemente é necessário validar a especificação dos dados do sistema, geralmente descrita por esquemas. O esquema de dados define a estrutura lógicae os relacionamentos entre os dados manipulados e armazenados por aplicações de software. Para auxiliar a detectar defeitos em esquemas e garantir a integridade dos dados por eles definidos, foi proposta uma abordagem de teste baseada em defeitos, denominada Análise de Instâncias de Dados Alternativas (AIDA). Na abordagem AIDA, uma instância de dados associada ao esquema em teste sofre alterações simples gerando instâncias de dados alternativas. A Análise de Instâncias de Dados Alternativas (AIDA) pode ser aplicada no teste de diferentes tipos de esquema, desde que o mesmo seja representado de acordo com um modelo formal. Apesar de existirem trabalhos na literatura que utilizam informações do esquema para testar as aplicações, a maioria não considera os possíveis efeitos presentes no esquema para gerar os dados de teste. Esses defeitos podem ocasionar falhas na aplicação e, considerando esse fato, este trabalho explora a utilização da AIDA no teste de aplicações que utilizam esquemas de dados, introduzindo estratégias de uso em dois contextos de aplicação: aplicações de banco de dados relacional e aplicações que utilizam Serviços Web. Para validar as estratégias em ambos contextos foram realizados experimentos em aplicações reais. Os resultados obtidos são analisados e verifica-se que a abordagem utilizada foi eficaz em revelar não somente defeitos de esquema, mas também defeitos relacionados à própria aplicação.

Dissertação de mestrado em Informática., Digital representations of Cultural Heritage (CH) and Natural Science (NS) artefacts often use collected data from the real world together with computer graphics techniques and skilled human intervention. A scholar will trust these representations when they are extended to digital surrogates, with all empir ical provenance information logged in. and use them when they are robust, affordable and easy to access and handle. This was the main context and motivation for this dissertation. Image-based techniques are a popular way to acquire and model surface materials. Reflectance Transformation Imaging (RTI) provide a powerful and efficient tool to build a model of the surface of an artefact, with a reliable 3D visualization, as analysed in this dissertation. An automated process pipeline was developed to acquire and build an RTI representation as a digital surrogate, in an open source context, the RTIbuilder. This automated process pipeline uses computer vision algorithms to acquire the information required by the generation stage and offers the user a set of tools for the most commonly used image processing procedures. The RTIbuilder not only apply software engineering techniques to solve the user’s problems, but also addresses most of the concerns posed by the scientific method: it removes the unreliable human factor from the RTI gen eration process during the workflow automation, by storing and preserving all the empirical provenance that include the unaltered empirical data gath ered, the process and parameters history and all human intervention over the gathered empirical information and process parameters. Workshops and tutorials were given to audiences with CH and NS profes sionals, and the RTIbuilder was field tested in several locations worldwide. Feedbacks were valuable to tune the application and opened new tracks for future work., Representações digitais de artefactos da herança cultural e das ciências natu rais usam dados do mundo real em combinação com técnicas de computação gráfica e intervenção de profissionais especializados. Um investigador apenas poderá confiar nestas representações digitais se elas forem convertidas em substitutos digitais, que deverão incluir toda a informação de proveniência. Técnicas baseadas em imagem são uma forma tradicional de capturar e modelar materiais. "Reflectance Transformation Imaging (RTI)" disponibi liza uma ferramenta poderosa e eficiente para construir uma representação da superfície de um artefacto, com uma visualização 3D fidedigna, tal como se demonstra ao longo desta dissertação. Foi desenvolvido um encadeamento de processos automático para capturar e produzir representações RTI enquanto substitutos digitais, num contexto de software aberto, dando origem a uma ferramenta designada RTIbuilder. Esta metodologia usa algoritmos de visão computacional para adquirir e calcular os parâmetros de entrada necessários à geração das representações RTI. Para além disso, disponibiliza um conjunto de ferramentas para as técnicas de processamento mais utilizadas no processo. O RTIbuilder, para além de aplicar técnicas de engenharia de software na resolução de problemas do utilizador, vai também ao encontro dos principais problemas decorrentes do método científico: remove a falibilidade humana do processo de geração de RTI, uma vez que armazena e preserva a proveniência empírica. A proveniência empírica engloba as observações empíricas recolhi das e inalteradas, a sequência de processos e respectivos parâmetros usados, bem como todo o histórico de manipulação da informação empírica recolhida e parâmetros de processo. Foram ministrados workshops e tutoriais a profissionais da herança cul tural e ciencias naturais e o RTIbuilder foi testado em situações reais em vários locais a nível mundial. Os resultados desses testes foram imprescindíveis para afinar a aplicação e abriu novos caminhos para trabalho futuro.

Entre os países ibero-americanos a História da Cartografia tem alguma tradição junto dos eruditos, dos militares e dos diplomatas: os velhos mapas espanhóis ou portugueses fazem parte do imaginário historiográfico ligado aos episódios da expansão geográfica europeia da Época Moderna; as cartas corográficas mexicanas ou brasileiras relaciona-as o público com a disputa e fixação das fronteiras no Novo Mundo, após as independências. Mas a quantidade e a qualidade dos documentos cartográficos pro...

Dissertação (Mestrado em Administração) - Pontifícia Universidade Católica de Minas Gerais, Belo Horizonte.

Dissertação de mestrado em Engenharia de Informática, Current computational platforms have become continuously more and more heterogeneous and parallel over the last years, as a consequence of incorporating accelerators whose architectures are parallel and different from the CPU. As a result, several frameworks were developed to aid to program these platforms mainly targeting better productivity ratios. In this context, GAMA framework is being developed by the research group involved in this work, targeting both regular and irregular algorithms to efficiently run in heterogeneous platforms. Scheduling is a key issue of GAMA-like frameworks. The state of the art solutions of scheduling on heterogeneous platforms are efficient for regular applications but lack adequate mechanisms for irregular ones. The scheduling of irregular applications is particularly complex due to the unpredictability and the differences on the execution time of their composing computational tasks. This dissertation work comprises the design and validation of a dynamic scheduler’s model and implementation, to simultaneously address regular and irregular algorithms. The devised scheduling mechanism is validated within the GAMA framework, when running relevant scientific algorithms, which include the SAXPY, the Fast Fourier Transform and two n-Body solvers. The proposed mechanism is validated regarding its efficiency in finding good scheduling decisions and the efficiency and scalability of GAMA, when using it. The results show that the model of the devised dynamic scheduler is capable of working in heterogeneous systems with high efficiency and finding good scheduling decisions in the general tested cases. It achieves not only the scheduling decision that represents the real capacity of the devices in the platform, but also enables GAMA to achieve more than 100% of efficiency as defined in [3], when running a relevant scientific irregular algorithm. Under the designed scheduling model, GAMA was also able to beat CPU and GPU efficient libraries of SAXPY, an important scientific algorithm. It was also proved GAMA’s scalability under the devised dynamic scheduler, which properly leveraged the platform computational resources, in trials with one central quad-core CPU-chip and two GPU accelerators., As plataformas computacionais actuais tornaram-se cada vez mais heterogéneas e paralelas nos últimos anos, como consequência de integrarem aceleradores cujas arquitecturas são paralelas e distintas do CPU. Como resultado, várias frameworks foram desenvolvidas para programar estas plataformas, com o objectivo de aumentar os níveis de produtividade de programação. Neste sentido, a framework GAMA está a ser desenvolvida pelo grupo de investigação envolvido nesta tese, tendo como objectivo correr eficientemente algoritmos regulares e irregulares em plataformas heterogéneas. Um aspecto chave no contexto de frameworks congéneres ao GAMA é o escalonamento. As soluções que compõem o estado da arte de escalonamento em plataformas heterogéneas são eficientes para aplicaçóes regulares, mas ineficientes para aplicações irregulares. O escalonamento destas é particularmente complexo devido à imprevisibilidade e ás diferenças no tempo de computação das tarefas computacionais que as compõem. Esta dissertação propõe o design e validação de um modelo de escalonamento e respectiva implementação, que endereça tanto aplicações regulares como irregulares. O mecanismo de escalonamento desenvolvido é validado na framework GAMA, executando algoritmos científicos relevantes, que incluem a SAXPY, a Transformada Rápida de Fourier e dois algoritmos de resolução do problema n-Corpos. O mecanismo proposto é validado quanto à sua eficiência em encontrar boas decisões de escalonamento e quanto à eficiência e escalabilidade do GAMA, quando fazendo uso do mesmo. Os resultados obtidos mostram que o modelo de escalonamento proposto é capaz de executar em plataformas heterogéneas com alto grau de eficiência, uma vez que encontra boas decisões de escalonamento na generalidade dos casos testados. Além de atingir a decisão de escalonamento que melhor representa o real poder computacional dos dispositivos na plataforma, também permite ao GAMA atingir mais de 100% de eficiência tal como definida em [3], executando um importante algoritmo científico irregular. Integrando o modelo de escalonamento desenvolvido, o GAMA superou ainda bibliotecas eficientes para CPU e GPU na execução do SAXPY, um importante algoritmo científico. Foi também provada a escalabilidade do GAMA sob o modelo desenvolvido, que aproveitou da melhor forma os recursos computacionais disponíveis, em testes para um CPU-chip de 4 núcleos e dois GPUs.