This paper studies the topological properties of the International Trade Network (ITN) among world countries using a network analysis. We explore the distribu- tions of the most important network statistics measuring connectivity, assortativ- ity and clustering. We show that the topological properties of the weighted rep- resentation of the ITN are very different from those obtained by a binary network approach. In particular, we find that: (i) the majority of countries are character- ized by weak trade relationships, (ii) well connected countries tend to trade with poorly connected partners and (iii) countries holding more intense trade relation- ships are more clustered. Finally, we display that all structural properties of the ITN have remained remarkably stable over time.

In the first part of this thesis, suitable function spaces for analysis of partial differ- ential equations in unbounded domains are introduced and studied. The results are then applied in the second part on semilinear wave equation in Rd with non- linear source term and nonlinear damping. The source term is supposed to be bounded by a polynomial function with a subcritical growth. The damping term is strictly monotone and satisfying a polynomial-like growth condition. Global existence is proved using finite speed of propagation. Dissipativity in locally uni- form spaces and the existence of a locally compact attractor are then obtained after additional conditions imposed on the damping term.

Title: Changes of lengths of periods with characteristic air temperatures Author: Eva Černochová Department: Department of Meteorology and Environment Protection Supervisor: doc. RNDr. Jaroslava Kalvová, CSc. Supervisor's e-mail address: jaroslava.kalvova@mff.cuni.cz Abstract: Lengths of periods with characteristic air temperatures were derived using two different methods (linear interpolation, robust locally weighted regression) for 10 stations in the Czech Republic and for output data of regional climate models HIRHAM and RCAO in 4 grid points. Averages for a forty-year period (1961-2000) and for a thirty-year period (1961-1990) were computed as well as averages for every decade. Considerable attention was also paid to the analysis of methods used in the research. Most stations showed lengthening of growing season and summer during the twentieth century. Decennary average length of growing season and summer shortened in the years 1971-1980. The comparison of output data of regional climate models HIRHAM and RCAO and measured station data showed that the thirty-year average lengths of growing season and summer estimated by the two models were reasonably accurate approximately half of all cases. The models' estimates were not accurate at all concerning decennary averages. Keywords: robust locally...

L'optimisation de l'exploitation d'un réseau de transport de gaz naturel (RTGN) est typiquement un problème d'optimisation multiobjectif, faisant intervenir notamment la minimisation de la consommation énergétique dans les stations de compression, la maximisation du rendement, etc. Cependant, très peu de travaux concernant l'optimisation multiobjectif des réseaux de gazoducs sont présentés dans la littérature. Ainsi, ce travail vise à fournir un cadre général de formulation et de résolution de problèmes d'optimisation multiobjectif liés aux RTGN. Dans la première partie de l'étude, le modèle du RTGN est présenté. Ensuite, diverses techniques d'optimisation multiobjectif appartenant aux deux grandes classes de méthodes par scalarisation, d'une part, et de procédures évolutionnaires, d'autre part, communément utilisées dans de nombreux domaines de l'ingénierie, sont détaillées. Sur la base d'une étude comparative menée sur deux exemples mathématiques et cinq problèmes de génie des procédés (incluant en particulier un RTGN), un algorithme génétique basé sur une variante de NSGA-II, qui surpasse les méthodes de scalarisation, de somme pondérée et d'ε-Contrainte, a été retenu pour résoudre un problème d'optimisation tricritère d'un RTGN. Tout d'abord un problème monocritère relatif à la minimisation de la consommation de fuel dans les stations de compression est résolu. Ensuite un problème bicritère, où la consommation de fuel doit être minimisée et la livraison de gaz aux points terminaux du réseau maximisée, est présenté ; l'ensemble des solutions non dominées est répresenté sur un front de Pareto. Enfin l'impact d'injection d'hydrogène dans le RTGN est analysé en introduisant un troisième critère : le pourcentage d'hydrogène injecté dans le réseau que l'on doit maximiser. Dans les deux cas multiobjectifs, des méthodes génériques d'aide à la décision multicritère sont mises en oeuvre pour déterminer les meilleures solutions parmi toutes celles déployées sur les fronts de Pareto. / The optimization of a natural gas transportation network (NGTN) is typically a multiobjective optimization problem, involving for instance energy consumption minimization at the compressor stations and gas delivery maximization. However, very few works concerning multiobjective optimization of gas pipelines networks are reported in the literature. Thereby, this work aims at providing a general framework of formulation and resolution of multiobjective optimization problems related to NGTN. In the first part of the study, the NGTN model is described. Then, various multiobjective optimization techniques belonging to two main classes, scalarization and evolutionary, commonly used for engineering purposes, are presented. From a comparative study performed on two mathematical examples and on five process engineering problems (including a NGTN), a variant of the multiobjective genetic algorithm NSGA-II outmatches the classical scalararization methods, Weighted-sum and ε-Constraint. So NSGA-II has been selected for performing the triobjective optimization of a NGTN. First, the monobjective problem related to the minimization of the fuel consumption in the compression stations is solved. Then a biojective problem, where the fuel consumption has to be minimized, and the gas mass flow delivery at end-points of the network maximized, is presented. The non dominated solutions are displayed in the form of a Pareto front. Finally, the study of the impact of hydrogen injection in the NGTN is carried out by introducing a third criterion, i.e., the percentage of injected hydrogen to be maximized. In the two multiobjective cases, generic Multiple Choice Decision Making tools are implemented to identify the best solution among the ones displayed of the Pareto fronts.

Icons surround us but are so ubiquitous they are difficult to observe. Specifically urban cultural icons are a scientific sub-topic under urban morphology's heading and as well are closely related to economic development issues. This study premises that businesses are urban cultural icons which can be computed into four rankings: local cultural icons, focal, zonal, and global cultural icons. And through using dimensional measurement an index is measured. This index can then be used to assess urban morphology. The data set ranges from businesses opening in 1865 to the present. Some are globally-distributed "big boxes"; others are unique one-store shops. The varied data set includes grocery stores, drug stores, prepared food vendors, confectioneries, coffee houses, electronic stores, and an adult entertainment store. Business rankings are premised upon Maslow's Hierarchy of Needs, Tönnies, and Oldenburg's places to socialize, and node intensity of social connection. Time is measured linearly and ordinally. Two formats of geographical ranking are assessed against each other, with the expanded version providing greater insights. Transactions are determined by who initiates them and location where employee enters exchange. Business' internal consistency is based upon product-line inclusion and theme-ing. Scaled measurements are summed with a comparison of Weighted-Place Index Scores against non-weighted Index Scores. As well, economic development impact of businesses is analyzed with three principal components loadings: two business survival and one growth mode. Study results support the use of Weighted-Place Index Scores as compared to nonweighted Index scores when formatting cultural icon index. Index score using four-level geographical ranking ranged from zero to 25. Morning Call Coffee House had lowest ranking (Index score of 3) and Best Buy had the highest score of 22. Weighted-Place Index Scores ranged from zero to 32, with Morning Call Coffee House continuing as lowest score and Starbucks, Bad Ass Coffee, as well ApplianceWorld and Best Buy continuing with four highest scores. This study supports a research method which can be used to measure urban change. By applying Index score within same cities at 20-year increments, sprawl process of globalization within cities can be analyzed.

Le sujet de cette thèse se divise en trois parties: les deux premières traitent chacune d'une extension du modèle utilisé en théorie des automates, tandis que la dernière aborde une partie plus concrète qui consiste à générer des automates avec des propriétés particulières. Tout d'abord, nous donnons une extension du concept d'automate universel, défini sur les mots finis, aux omega-langages. Pour cela, nous avons défini une forme normale pour tenir compte de la spécificité du mode d'acceptation des automates de Büchi qui nous permettent de reconnaître les omega-langages. Ensuite nous avons défini deux types d'omega-factorisations, "classiques" et "pures", qui sont des extensions du concept de factorisation d'un langage, ce qui nous a permis de définir l'automate universel d'un omega-langage. Nous avons prouvé que ce dernier dispose bien des différentes propriétés attendues: il est le plus petit automate de Büchi reconnaissant l'omega-langage et qui possède la propriété d'universalité (moyennant la forme normale). Nous présentons également une méthode pour calculer efficacement les omega-factorisations maximales d'un langage à partir d'un automate prophétique reconnaissant le dit langage. Dans la seconde partie, nous traitons le cas des automates bidirectionnels à multiplicité dans un semi-anneau. Dans un premier temps, nous donnons une version légérement différente de la construction permettant de passer d'un automate bidirectionnel à multiplicité à un automate unidirectionnel à multiplicité et nous prouvons qu'elle préserve la non-ambiguïté mais pas le déterminisme. Nous montrons, également à l'aide d'une construction, que les automates bidirectionnels à multiplicité non-ambigus sont équivalents aux automates unidirectionnels à multiplicité déterministes. Dans un second temps, nous nous concentrons sur les semi-anneaux tropicaux (ou min-+). Nous montrons que sur N-min-+, les automates bidirectionnels sont équivalents aux automates unidirectionnels. Nous montrons également que sur Z-min-+, les automates bidirectionnels n'ont pas toujours un comportement défini et que cette propriété est décidable tandis qu'il n'est pas décidable s'il existe un mot pour lequel le comportement est défini. Dans la dernière partie, nous proposons un algorithme de génération aléatoire d'automate acycliques, accessibles et déterministes ainsi que d'automates acycliques minimaux avec une distribution qui est quasiment uniforme, tout cela à l'aide de chaîne de Markov. Nous prouvons l'exactitude de chacun de ces deux algorithmes et nous expliquons comment adapter en tenant compte de contraintes sur l'ensemble des états finals / The subject of this thesis is decided into three parts: two of them are about extensions of the classical model in automata theory, whereas the third one is about a more concrete aspect which consists in randomly generate automata with specific properties. We first give an extension of the universal automaton on finite words to infinite words. To achieve this, we define a normal form in order to take account of the specific acceptance mode of Büchi automata which recognize omega-langages. Then we define two kinds of omega-factorizations, a "regular" one and the "pure" kind, which are both extensions of the classical concept of factorization of a language. This let us define the universal automaton of an omega-language. We prove that it has all the required properties: it is the smallest Buchi automaton, in normal form, that recognizes the omega-language and which has the universal property. We also give an effective way to compute the "regular" omega-factorizations of a language using a prophetic automaton recognizing the language. In the second part, we deal with two-way automata weighted over a semi ring. First, we give a slightly different version of the computation of a weighted one-way automaton from a weighted two-way automaton and we prove that it preserves the non-ambiguity but not the determinism. We prove that non-ambiguous weighted two-way automata are equivalent to deterministic weighted one-way automata. In a later part, we focus on tropical semi rings (or min-+). We prove that two-way automata on N-min-+ are equivalent to one-way automata on N-min-+. We also prove that the behavior of two-way automata on Z-min-+ are not always defined and that this property is decidable whereas it is undecidable whether or not there exists a word on which the behavior is defined. In the last section, we propose an algorithm in order to randomly generate acyclic, accessible and determinist automata and minimal acyclic automata with an almost uniform distribution using Morkov chains. We prove the reliability of both algorithms and we explain how to adapt them in order to fit with constraints on the set of final states

The theoretical part of the diploma thesis deals with the main aspects of financial analysis, especially with horizontal and vertical analysis of absolute values, financial ratios, new valuation models and bankruptcy prediction models. The following part concentrates on the company Crocodille ČR, spol. s r.o. using the theoretical approaches mentioned above. It focuses on trend analysis, the calculation of Weighted Average Cost of Capital and Economic Value Added as well as industry comparative analysis. The final recommendations regarding e.g. the sensitivity analysis of company indebtedness are included in the last chapter.

[pt] No Brasil, assim como em outros países, a prestação de serviço público de energia elétrica é realizada em concessão sob a coordenação de um órgão regulador independente, atividade que no Brasil é desempenhada pela Aneel – Agência Nacional de Energia Elétrica. É também competência da Aneel a estimação do WACC regulatório – custo médio ponderado de capital do setor elétrico, que remunerará o capital dos investidores do setor, por intermédio das tarifas, até o final do ciclo de revisão tarifária vigente, que ocorre em média a cada cinco anos. Para tanto, o regulador se utiliza de dados da economia norte - americana adaptados para a realidade local, por entender que a bolsa brasileira possui limitações no que tange a consistência das séries. Imprecisões no cálculo do WACC podem levar a concessionária a perceber ganhos adicionais, no caso de uma taxa superestimada, ou perdas, no caso de uma taxa subestimada, podendo resultar em uma possível redução nos investimentos que poderiam afetar a qualidade no serviço prestado ou planos de expansão. Passam por tanto a ser de interesse de toda a sociedade discussões em torno de um aprimoramento da metodologia aplicada na estimação do custo de capital do setor. A proposta apresentada neste trabalho é estimar o custo médio ponderado de capital do setor de distribuição elétrico brasileiro, por meio de aprimoramentos na metodologia atual adotada pelo órgão regulador do setor, alinhando com as melhores práticas da teoria de finanças. Os resultados apontam para a necessidade de aprofundamento de discussões pelo regulador considerando algumas alternativas nos critérios de estrutura de capital, taxa livre de risco, risco-país e prêmio de risco de crédito. / [en] In Brazil, as in other countries public utilities are operated as concessions under the coordination of an independent regulatory agency, a role played in Brazil by Aneel– National Agency of Electricity. It is also Aneel s responsibility the estimation of regulatory WACC – weighted average cost of capital of the electricity sector which remunerates investors capital through tariffs until the end of the current tariff review cycle that occurs on average every 5 years. For that the regulator based the calculation of the WACC on American economic data adapted to Brazil reality assuming that data from Brazilian stock exchange series have some limitation. Inaccuracies in the WACC can lead to companies obtaining additional gains in the case of an overestimated rate, or losses in the event of an underestimated, which might result in reduction in investments and could affect the quality of service or expansion plans. Therefore, it is in the interest of society to discuss improvements of the methodology applied in estimating the cost of capital in the sector. This study aims to estimate the weighted average cost of capital of the Brazilian electricity distribution sector through improvements in current methodology adopted by the regulatory agency, aligning it with finance theory best practices. Results indicate the need for deeply discuss from the regulator about some alternatives improvement in the capital structure, risk free rate, country risk and credit risk premium.

[pt] Há diferentes tipos de investidores que compõem o mercado financeiro e produzem oportunidades de mercado em diferentes escalas de tempo. Isto evidencia uma estrutura heterogênea de mercado. Nesta tese conjecturamos que podem haver oportunidades mais preditivas do que outras, o que motiva a investigação e a construção de estratégias multirresolução. Para estratégias multirresolução há abordagens que utilizam a decomposição de séries temporais para a operação em resoluções distintas ou propostas para a construção de conjuntos de dados de acordo com decisões de negociação multirresolução. As demais estratégias, em sua maioria, são de resolução única. Nesta tese, abordamos dois problemas, maximização de retorno acumulado e maximização de retorno acumulado com o risco controlado, e propomos uma abordagem computacionalmente eficiente para a construção de estratégias multirresolução, a partir da resolução do problema de Agendamento de Intervalos Ponderados. Nossa metodologia consiste em dividir o dia de mercado em intervalos, especializar traders por intervalo e associar um prêmio a cada trader. Para o problema de maximização de retorno acumulado, o prêmio de cada trader corresponde ao retorno acumulado entre dias para o intervalo de operação associado. Para o problema de maximização de retorno acumulado com controle do risco, o prêmio de cada trader corresponde ao retorno acumulado dividido pelo risco para o intervalo de operação associado. Diferentemente do problema anterior, empregamos um conjunto de traders por intervalo e utilizamos o método de Média-Variância, de Markowitz, para encontrar pesos ótimos para conjunto de traders de forma a controlar o risco. Conjecturamos aqui que o controle do risco por intervalo acarreta no controle do risco global da estratégia para o dia. Para a sinalização das ordens de compra e venda, nossos traders utilizam detectores de oportunidades. Estes detectores utilizam algoritmos de Aprendizado de Máquina que processam informações de indicadores de análise técnica e dados de preço e volume. Realizamos experimentos para dez ativos de maior liquidez da BMF&Bovespa para um período de um ano. Nossa estratégia de Composição de um Time de Traders (CTT) apresenta 0, 24 por cento de lucro médio diário e 77, 24 por cento de lucro anual, superando em 300 por cento e 380 por cento, respectivamente, uma estratégia de resolução única. Para os custos adotados, a estratégia CTT é viável a partir de 50.000,00 dólares. Para o problema de maximização do retorno acumulado com risco controlado, a estratégia de Composição de Carteiras por Intervalos (CCI) apresenta em média 0, 179 por cento de lucro diário e 55, 85 por cento de lucro anual, superando o método de Média-Variância de Markowitz. Para os custos adotados, a estratégia CCI é viável a partir de 2.000.000,00 dólares. As principais contribuições desta tese são: abordagem por Agendamentos de Intervalos Ponderados para a construção de estratégias e o emprego do modelo de Média-Variância para compor uma carteira de traders ao invés da tradicional abordagem por ativos. / [en] There are different types of investors who make up the financial market and produce market opportunities at different time scales. This indicates a heterogeneous market structure. In this thesis, we conjecture that may have more predictive opportunities than others, what motivates research and construction of we denominate multirresolution optimal strategies. For multirresolution strategies there are time series decomposition approaches for operating at different resolutions or proposals for dataset construction according to multirresolution trading optimal decisions. The other approaches, are single resolution. Thus, we address two problems, maximizing cumulative returns and maximizing cumulative returns with risk control. Here, we propose solving the Weighted Interval Scheduling problem to build multirresolution strategies. Our methodology consists of dividing the market day into time intervals, specialize traders by interval and associate a prize to each trader. For the cumulative return maximization problem, the prize corresponds to cumulative returns between days for the associated trader operation interval. For the cumulative return maximization problem with risk control each trader prize corresponds to cumulative return divided by risk with associated operation interval. In order to control the risk, we employ a set of traders by interval and apply the Markowitz Mean-Variance method to find optimal weight for set of traders. Here, we conjecture that controlling each interval risk leads to the overall risk control of the day. For signaling buy and sell orders, our traders use opportunity detectors. These detectors correspond to Machine Learning algorithms that process technical analysis indicators, price and volume data. We conducted experiments for ten of the most liquid BMF&Bovespa stocks to a one year span. Our Trading Team Composition strategy results indicates an average of 0.24 per cent daily profit and a 77.24 per cent anual profit, exceeding by 300 per cent and 380 per cent, respectively, a single resolution strategy. Regarding operational costs, CTT strategy is viable from 50,000 dollars. For the cumulative return maximization problem under risk control, our Portfolio Composition by Intervals strategy results indicates an average of 0.179 per cent daily profit and a 55.85 per cent anual profit, exceeding a Markowitz Mean- Variance method. Regarding operational costs, CCI strategy is viable from 2,000,000 dollars. Our main contributions are: the Weighted Interval Scheduling approach for building multirresolution strategies and a portfolio composition of traders instead of stocks performances.

Tout d'abord, cette recherche examine le capitalisme partagé, le développement théorique et historique de la participation des salariés, et les droits de propriété. Deuxièmement, la thèse analyse empirique sur les perspectives de l'actionnariat salarié. Premièrement, la période du 19ème siècle jusqu'au début du 21ème siècle en Allemagne est recherchée. Nous essayons de répondre à la question : "Est-ce que les décideurs politiques en Allemagne veulent créer une société de propriétaires ?" Au cours de la recherche, nous montrons l'hypothèse "L'actionnariat salarié est un critère des pères fondateurs de l'Allemagne afin de stabiliser Allemagne socio-économique après la Seconde guerre mondiale. Supporté bien évidemment par une étude qualitative de recherches d'archives historiques. En Allemagne, il est évident que les pères fondateurs ont poursuivis "Wohlstand für Alle" à travers les actions des citoyens. Deuxièmement, cette recherche examine la relation entre l'actionnariat salarié et le WACC. La thèse analyse le conflit entre les parties prenantes internes et externes, qui est représenté par le cours des actions d'une entreprise en supposant un marché efficace. Nous émettons l'hypothèse : «Un pourcentage plus élevé d'actions détenues par les salariés provoque un WACC inférieur" Ceci est confirmé par un modèle de régression quantitative fixe de panneau d'effet dans le cas de l'indice Société des Bourses Françaises 120 et l'indice 500 de Standard & Poor. / Firstly, this research examines shared capitalism, the theoretical and historical development of employee participation, and ownership rights. Secondly, the thesis analyzes empirically perspectives on employee stock ownership. First, the period from the 19th century until the beginning of the 21st century in Germany is researched. We attempt to answer the question: "Did policy makers in Germany want to create a society of owners?" During the research we prove the hypothesis "Employee ownership was a criterion of Germany's founding fathers in order to stabilize Germany socio-economically after the Second World War." We confirm it through a qualitative study of historical archive researches. In Germany, there is clear evidence that founding fathers pursued "Wohlstand für Alle" through citizen's shares. Second, this research examines the relationship between employee stock ownership and the weighted average cost of capital. The thesis analyzes the conflict between internal and external stakeholders, which is represented through a company's stock price assuming an efficient market. We hypothesize: "A higher percentage of shares held by employees causes a lower WACC." This is confirmed through a quantitative fixed effect panel regression model in the case of the Société des Bourses Françaises 120 index and Standard & Poor's 500 index.