Global Hypoellipticity for Strongly Invariant Operators

In this note, by analyzing the behavior at infinity of the matrix symbol of an invariant operator $P$ with respect to a fixed elliptic operator, we obtain a necessary and sufficient condition to guarantee that $P$ is globally hypoelliptic. We also investigate relations between the global hypoellipticity of $P$ and global subelliptic estimates.Comment: 20 page

is the European Union doing its best to prevent them?

Diversos instrumentos de direito internacional do mar impõe aos Estados Membros da União Europeia a obrigação de assegurar serviços de busca e salvamento eficientes. Por é m, desde 2013, 19 956 pessoas morreram ou desapareceram ao tentar atravessar o Mar Mediterrâneo. Isto é o resultado de uma infeliz combinação de políticas de combate ao tráfico de migrantes, que poderão estar inadvertidamente a tornar a travessia do Mediterrâneo ainda mais perigosa; de práticas que privilegiam o controlo fronteiriço em detrimento de operações de busca e salvamento; e de leis que permitem que os Estados punam organizaçõ es n ão governamentais que, de forma voluntária, tentam preencher a existen t e lacuna operaci onal de salvamento Devido à insufici ência de vias que permitam aos migrantes chegar à Europa de modo regular, estes vão continuar a tentar fazê lo irregularmente e continuarão a perder se vidas. Por isso, é urgente e necess ário fazer mais para o s resgata r. Atendendo ao regime jurídico internacional de busca e salvamento marítimo e ao princípio da solidariedade e da partilha equitativa de responsabilidades, a União Europeia deve promover um acordo regional atrav é s do qual a responsabilidade pelas operações de busca e salvamento no Mediterrâneo possa ser redistribuída entre os Estados Membros Estas deverão distinguir se das competências de controlo fronteiriço e das de combate ao tráfico de migrantes, tanto na lei, como na prática, atendendo à natureza dive rsa dos objetivos em causa Mormente, o envolvimento de organizaçõ es n ão governamentais nestas operações deve ser valorizado e não criminalizado, pelo que as leis europeias em mat éria de aux í lio à entrada e ao trânsito irregulares devem ser revistas. Final mente, devem ser imediatamente abandonadas quaisquer políticas que visem impedir entradas irregulares e que sejam incompatíveis com o direito internacional dos direitos humanos.Several international law of the sea instruments impose on the European Union and on its Member State s the obligation to ensure efficient maritime search and rescue services. In spite of this, since 2013, a total of 19 956 people attempting to cross the Mediterranean Sea have either died or gone missing. This is the result of an unfortunate combination of European laws, policies and practices. Policies aimed at combating migrant smuggling which may inadvertently be making the Mediterranean Sea even deadlier. Practices which prioritise border control operations over maritime search and rescue. And laws that allow for States to prosecute non governmental organisations which volunteer to fill in the resultant operational gap. Due to insufficient legal pathways for migration, migrants will keep on trying to reach Europe irregularly and thus lives will continue to be lost at sea. For this reason, it remains urgent and necessary to do more to rescue them. In line with the international legal framework of maritime search and rescue and with the principle of solidarity and fair sharing of responsibilities, the Europ ean Union must promote the development of a regional agreement through which responsibility for search and rescue in the Mediterranean can be shared. These services need to be separate from border control and from anti migrant ’s smuggling operations, both in law and in practice, due to the conflicting nature of their respective goals. Additionally, the involvement of non governmental organisations in these operations must be valued, not criminalised. As such, the European Union's laws on facilitation of una uthorised entry, transit and residence must be revised. Finally, policies aimed at directly or indirectly preventing irregular arrivals which do not comply with international human rights law must be immediately abandoned

Le soutien de l´académie aux rencontres internationales dans le cadre du Processus de Bologne

Dans le cadre du soutien institutionnel auquel sont déjà obligés Universités et autres établissements d’enseignement, on réfléchira aux implications de la construction européenne en ce qui concerne les Conférences européennes et, en particulier, le Processus de Bologne. On en déduira ensuite quelques principes, en suggérant un certain nombre de bonnes pratiques qui devraient être appliquées à l’espace global de l’Enseignement Supérieur. A reflection is made about certain implications of European construction in the domain of the institutional support Universities and other learning institutions should provide to European Conferences that implicitly are underlying Bologna Process. Some rules are deduced and some good practices are suggested, which should in fact be extended to a global space of Higher Education

Risk profiling: perception and reality

Mestrado em FinançasRetail banks classification of clients according to their risk profile has been a theme very much under discussion in the last few years. In this paper we aim to investigate, for the affluent and private banking client segment, if the perception that people have of their risk profile effectively corresponds to their real risk profile as given by a measure of historical volatility. In addition, we analyze, on the real portfolio of financial investments, the impact of each of the following factors in regard to people's attitude towards risk: age, gender, degree of education, financial situation and investment experience

CleanGraph - Graph viewing and editing for family trees and UML class diagrams

Traditionally, different types of diagrams are used to represent varying types of data in a fast and easy way to read. Their usage includes describing systems, understanding their features and presenting how different parts are interconnected, making them useful for many applications. Unfortunately, as the complexity of the data showed increases, so does the complexity of the diagram, making it more difficult to read and interpret. Since interactions are usually limited to panning and zooming, there is room for improvement with more interaction and different input methods. The goal is to tackle these issues in two types of diagrams -- Family Trees (FT) and Universal Modeling Language (UML) class diagrams. To achieve this, a new platform will be created, capable of generating diagrams and displaying them in a way where overlapping and unrelated data is minimised alongside having better methods for interacting with and manipulating information. These diagrams will prioritise visual clarity by grouping together elements with relevant or important information, as well as having new ways of interaction, such as selecting elements to receive more information and manually grouping them to better explore the data. Guaranteeing the viability of the solution will require two main issues to be addressed: (1) Defining a fitting diagram disposition and why it is the more advantageous; (2) Understanding the best way to create interactions with diagrams while making it intuitive and keeping them readable. Finding the best platform for the solution to reach its intended audience while providing the desired ease of use is one of the priorities. The evaluation of this work will be attained through previously defined metrics, to ensure that the generated diagram is adequate. The quality of the diagrams will be defined by characteristics such as overlapping connections between elements, related or unrelated data of adjacent elements to the selected one and the amount of displayed data at once. The result of the proposal aims to give a better tool to users seeking improved methods to view their ancestry data, as well as software architects, project managers and system analysts, who would benefit from a better platform for system representation. The developed features can help them convey their ideas easily to developers or anyone interested in the data represented, improving simplicity, workflow and potentially bringing new and improved methods of viewing and displaying information in these areas

The impact of capital regulation on banks' cost and profit efficiency under stressful economic conditions : cross-country evidence

This thesis evaluates how regulation on capital requirements is associated with cost and profit efficiency of banks. It allows an international comparison on banking regulation, capturing changes on public policies towards banks over time further, it encompasses one of the major financial crises since 1929. The impact of regulatory capital requirements on banking efficiency is assessed using the stochastic frontier production function for panel data to estimate inefficiency effects. It is used a panel dataset of 865 observations from 156 publicly listed commercial banks operating in 30 countries and covering a nine year time-horizon (2004-2012). Besides the impact on capital regulation, we also controlled for the influence of other regulatory variables, macroeconomic conditions, market structure characteristics and the state of financial development. Our results suggest that capital requirements negatively affect inefficiency, meaning that, for our sample, an increase on regulatory equity ratios will lead to an efficiency improvement. Regarding other regulatory control variables, we would say that regulation should aim to increase market discipline, while restricting banks activities. The power of supervisory agencies seems to negatively impact banks’ efficiency, but in in stressful conditions, it may help banks being more cost efficient

The role of electron transfer in DNA building blocks: evaluation of strand breaks and their implications

Dissertação para obtenção do Grau de Doutor em Engenharia FísicaRadiation-induced damage to biological systems, both direct and indirect processes, has increasingly come under scrutiny by the international scientific community due to recent findings that electrons are a very effective agent in damaging DNA/RNA. Indeed, much remains to be discovered regarding the exact physico-chemical processes that occur in the nascent stages of DNA/RNA damage by incident radiation. However, it is also known that electrons do not exist freely in the physiological medium, but rather solvated and/or pre-solvated states. This leads to the need for new techniques that can better explore the damaging role of “bound” electrons to DNA/RNA. The work presented in this thesis consists on the study of electron transfer in collisions of atomic species with molecules of biological relevance. In order to study these processes, two experimental setups were used. One setup consists of a crossed beam experiment where a neutral potassium beam is created and made to collide with an effusive molecular target beam. The anionic products that stem from electron transfer in potassium atom to the molecular target collisions are then extracted and time-of-flight (TOF) mass analysed. In the second setup a beam of anionic species is formed and made to collide with a molecular target. Collisions with three different anionic beams were performed (H-, O- and OH-), as well as with different simple organic molecules, by measuring the positive and negative ion fragmentation patterns with a quadrupole mass spectrometer (QMS). A comparison between these two collisional systems can greatly help to understand the underlying mechanisms of the electron transfer processes. Finally, studies of potassium collisions with sugar surrogates D-Ribose and THF were performed. These studies show very different fragmentation patterns from DEA, although in the case of THF, it is suggested that the initially accessed states are the same as in DEA. With these studies was also possible to show for the first time collision induced site and bond selectivity breaking, where the electron is transferred into a given state of the acceptor molecule and the resulting fragmentation pathways are exclusive to the initial anionic state. Furthermore, the role of the potassium cation post collisionwas explored and indeed its presence is suggested to induce at least partial suppression of auto-detachment. The implications that ensue from this degradation are analysed in the light of the obtained fragmentation patterns

Redes definidas por software flexíveis

The fifth generation of mobile networks (5G) are able to offer better services than its predecessors mainly through the usage of software defined networks (SDN) and network functions virtualization (NFV) However, after multiple solutions developed using OpenFlow, the conclusion was that the even after several years of the first version released, OpenFlow fails to offer full flexibility and cannot handle unknown protocols. With that in mind, the community got together and created what is known today as P4. P4 is a language designed to program the data plane behavior, that, with the help of P4Runtime, the alternative of OpenFlow to P4 enabled devices, it allows the management of the data plane behavior regarding the target or the protocol. All of that because, unlike OpenFlow, P4Runtime does not assume that network devices have a fixed and well defined behavior, usually described by the ASIC chip. In this work, P4 ecosystem is used to implement offloading of functions to the network devices and evaluate whether that is impactful for the network performance. Given the low amount of work developed with P4 regarding publish-subscribe systems, that traditionally rely on brokers, it was decided to offload several functions of such systems to the dataplane with P4, leading that the overall solution can be comparable to distributed broker ones. However, P4 is limited regarding the management of state related data, just like of TCP sessions, which many publish-subscribe system rely on. Zenoh, a new publish-subscribe protocol that is still in early phases and directed to IoT, is also able to run over UDP and therefore is a great candidate to be implemented in P4 to overcome such issues. It is then used to show the advantages of doing offloading of processing to the dataplane. The conceptualized system was then compared to two more traditional ones, that do not make use of offloading. The overall results achieved are promising. Results show that there are benefits in the offloading of certain tasks to the dataplane and therefore be closer to the end user and with that improve latency. However, regarding the pure Zenoh, the results achieved are poorer. That can be explained by the usage of software switches that are not production grade ready and whose performance is highly impacted by several data plane factors. That makes it necessary to do more tests on expensive hardware equipment for a more concrete conclusion.As redes móveis de quinta geração (5G) conseguem oferecer melhores serviços que as suas anteriores gerações maioritariamente através do uso de tecnologias como redes definidas por software (SDN) e virtualização das funções da rede (NFV). No entanto, após vários anos de implementações de soluções usando OpenFlow, chegou-se à conclusão que este tem limitações relativamente a protocolos desconhecidos, mesmo após vários anos da primeira versão. Então, a comunidade juntou-se e criou o que hoje é o ecossistema P4/P4Runtime. Sendo o P4 uma linguagem destinada à programação do comportamento do plano de dados e o P4Runtime o equivalente ao OpenFlow para equipamentos que suportam P4, no entanto permite uma gestão do comportamento do plano de dados independente do dispositivo e do protocolo, uma vez que não assume que os equipamentos de rede têm um comportamento fixo bem definido, normalmente descrito pelo chip ASIC. Neste trabalho, faz-se uso do ecossistema do P4 para implementação de offloading de funções para os próprios equipamentos de rede e avalia-se se esta solução traz benefícios para a performance da rede. Devido à pouca exploração em P4 de sistemas publish-subscribe, que dependem tradicionalmente de brokers, foi decidido fazer offloading de funções de um desses sistemas através do uso de P4, permitindo ainda que a solução como um todo possa ser comparável com as oferecidas por um broker distribuído. No entanto, o P4 tem limitações ao nível de gestão de sessões TCP. O Zenoh, um protocol publish-subscribe ainda em evolução e direcionado para IoT, permite também transporte sobre UDP, e é por isso um grande candidato a ser implementado em P4 para demonstrar as vantagens de fazer offloading de processamento para o plano de dados. O sistema conceptualizado e desenvolvido foi então comparado com outros dois sistemas mais tradicionais que não fazem uso de offloading. Os resultados são animadores mostrando que existe benefício em fazer ffloading de certas funções para o plano de dados, visto que certas operações podem ser feitas mais perto do utilizador final. No entanto, comparando os resultados com os oferecidos pelo Zenoh puro, os resultados são piores, sendo isto explicado pelo facto de os equipamentos de rede utilizados serem switches em software que não estão preparados para ambientes de produção e são muito penalizados por diversos fatores do comportamento do plano de dados. É por isso necessário fazer testes em equipamentos de hardware para uma avaliação mais profunda e consequente conclusão.Mestrado em Engenharia de Computadores e Telemátic

Equity research: Jerónimo Martins SGPS, SA

The main objective of this dissertation is to carry out a global valuation of Jerónimo Martins and determine its value per share based on cash flows forecasts. In that sense, an analysis of the company was made, as well as a market study regarding the evolution of the retail industry. Jerónimo Martins SGPS is a Portuguese company, leader in the food retail market in Poland and one of the major players in the Portuguese market, beyond that it is also presence in the Colombian market. Jerónimo Martins also operates in the specialized retail, namely in cosmetics and confectionery markets and in the agribusiness industry. On 31/12/2020 Jerónimo Martins SGPS was listed on the Euronext Lisbon stock exchange and closed the year with a value of €13.82 per share. To determine the company value three valuation methods were used, the DCF, the EVA and the multiples methodology. According with the DCF model, the target price is €13.92, which represents an appreciation of 0.76% and thus the value offered by the market does not recognize the potential growth of the company. A sensitivity analysis was also performed to analyse the sensitivity of the share price to the discount rate and to the perpetual growth rate, two of the most crucial variables. In conclusion, it was done a comparative analysis of the results obtained through the several methods, which lead to a Buy recommendation, in line with the analysis carried out by CAIXA BANK.Esta dissertação tem como principal objetivo realizar uma avaliação global à Jerónimo Martins e determinar o valor das suas ações com base nas perspetivas futuras. Para isso, foi feita uma análise da empresa e também um estudo ao mercado que engloba a evolução do setor do retalho. A Jerónimo Martins SGPS é uma empresa portuguesa, líder no mercado alimentar na Polónia e um dos maiores players no mercado português e conta ainda com presença no mercado Colombiano. A Jerónimo Martins tem também presença no retalho especializado, nomeadamente em cosmética e confeitaria e também no mercado agro-alimentar. A 31/12/2020 a Jerónimo Martins SGPS estava cotada na bolsa de valores Euronext Lisboa e fechou o ano com as ações a valerem 13.82 euros Para determinar o valor da empresa vão ser utilizados três métodos de avaliação, o DCF, o EVA e por último, foi utilizado o método dos múltiplos. Segundo o modelo DCF, o preço alvo é de €13.92, o que representa uma apreciação de 0.76% e deste modo o valor oferecido pelo mercado não reconhece o potencial crescimento da empresa. Foi também realizado uma análise de sensibilidade tendo por base variações em duas das variáveis mais críticas, para que seja possível avaliar a sensibilidade do preço da ação relativamente à taxa de desconto e à taxa de crescimento perpétuo. Em suma, é também realizada uma comparação dos resultados obtidos através dos diversos métodos, o que origina uma recomendação de compra, em linha com a análise realizada pelo CAIXA BANK

Real-time collaborative editing of OutSystems DSL models

Real-time collaborative editing systems are common nowadays, and their advantages are widely recognized. Examples of such systems include Google Docs, ShareLaTeX, among others. This thesis aims to adopt this paradigm in a software development environment. The OutSystems visual language lends itself very appropriate to this kind of collaboration, since the visual code enables a natural flow of knowledge between developers regarding the developed code. Furthermore, communication and coordination are simplified. This proposal explores the field of collaboration on a very structured and rigid model, where collaboration is made through the copy-modify-merge paradigm, in which a developer gets its own private copy from the shared repository, modifies it in isolation and later uploads his changes to be merged with modifications concurrently produced by other developers. To this end, we designed and implemented an extension to the OutSystems Platform, in order to enable real-time collaborative editing. The solution guarantees consistency among the artefacts distributed across several developers working on the same project. We believe that it is possible to achieve a much more intense collaboration over the same models with a low negative impact on the individual productivity of each developer