Teoria de carteiras e a alocação de parques eólicos offshore

The consumption of energy on the planet is currently based on fossil fuels. They are responsible for adverse effects on the environment. Renewables propose solutions for this scenario, but must face issues related to the capacity of the power supply. Wind energy offshore emerging as a promising alternative. The speed and stability are greater winds over oceans, but the variability of these may cause inconvenience to the generation of electric power fluctuations. To reduce this, a combination of wind farms geographically distributed was proposed. The greater the distance between them, the lower the correlation between the wind velocity, increasing the likelihood that together achieve more stable power system with less fluctuations in power generation. The efficient use of production capacity of the wind park however, depends on their distribution in marine environments. The objective of this research was to analyze the optimal allocation of wind farms offshore on the east coast of the U.S. by Modern Portfolio Theory. The Modern Portfolio Theory was used so that the process of building portfolios of wind energy offshore contemplate the particularity of intermittency of wind, through calculations of return and risk of the production of wind farms. The research was conducted with 25.934 observations of energy produced by wind farms 11 hypothetical offshore, from the installation of 01 simulated ocean turbine with a capacity of 5 MW. The data show hourly time resolution and covers the period between January 1, 1998 until December 31, 2002. Through the Matlab R software, six were calculated minimum variance portfolios, each for a period of time distinct. Given the inequality of the variability of wind over time, set up four strategies rebalancing to evaluate the performance of the related portfolios, which enabled us to identify the most beneficial to the stability of the wind energy production offshore. The results showed that the production of wind energy for 1998, 1999, 2000 and 2001 should be considered by the portfolio weights calculated for the same periods, respectively. Energy data for 2002 should use the weights derived from the portfolio calculated in the previous time period. Finally, the production of wind energy in the period 1998-2002 should also be weighted by 1/11. It follows therefore that the portfolios found failed to show reduced levels of variability when compared to the individual production of wind farms hypothetical offshore

Structural change and domestic technological capabilities

Includes bibliography

O cinema de Manoel de Oliveira: um caso singular

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Using 3D Animations in Teaching Chemistry

This paper discuss possibilities of use of 3D animation as a tool for teaching Chemistry support. The research proposes to investigate the conception process and development of educational animations to use in a Blended Learning environment in undergraduate chemistry. Associated with general chemistry teachers, were raised the demands and difficulties on the content transmission, and the most relevant topics, about "Atomic Theory" with propose to create appropriate animations to meeting needs of themes. Thinking about offering more dynamic materials, we elaborate animations in a format of "micro-documentary", with a length between 4 and 7 minutes. We use the narration aloud to the subject-matter understanding, leaving the external text as a complement of the animation. The conclusions are positives, students accepted well the format and they proved are able to remember, organize and systematize several information presented in animations. These skills don't ensure knowledge acquisition, but may be considered prerequisites to learning occur.

Aplicação da moderna teoria do Portfólio em ativos não financeiros

The Markowitz's objective functions, Value-at-Risk and Conditional Value-at-Risk, are largely used tools in the financial Market for portfolio optimization. This paper tries to analyze these functions having as a target to adapt them for application in non-financial assets portfolios. The paper uses as an example the Electricity Market to analyze and optimize a fictitious investment portfolio of a possible electric power utility. Showing that, besides being possible, which considerations must be taken and which analysis must be made to apply the Modern Portfolio Theory in the non-financial universe

A New Control Architecture for Robust Controllers in Rear Electric Traction Passenger HEVs

It is well known that control systems are the core of electronic differential systems (EDSs) in electric vehicles (EVs)/hybrid HEVs (HEVs). However, conventional closed-loop control architectures do not completely match the needed ability to reject noises/disturbances, especially regarding the input acceleration signal incoming from the driver's commands, which makes the EDS (in this case) ineffective. Due to this, in this paper, a novel EDS control architecture is proposed to offer a new approach for the traction system that can be used with a great variety of controllers (e. g., classic, artificial intelligence (AI)-based, and modern/robust theory). In addition to this, a modified proportional-integral derivative (PID) controller, an AI-based neuro-fuzzy controller, and a robust optimal H-infinity controller were designed and evaluated to observe and evaluate the versatility of the novel architecture. Kinematic and dynamic models of the vehicle are briefly introduced. Then, simulated and experimental results were presented and discussed. A Hybrid Electric Vehicle in Low Scale (HELVIS)-Sim simulation environment was employed to the preliminary analysis of the proposed EDS architecture. Later, the EDS itself was embedded in a dSpace 1103 high-performance interface board so that real-time control of the rear wheels of the HELVIS platform was successfully achieved.

Crítica y poesía. Elementos para una tradición

Este ensayo estudia las operaciones epistemológicas actuantes en la crítica argentina contemporánea de poesía, tomando en cuenta el estatuto teórico-filosófico de su discurso. Para ello, postula una tradición emergente en las últimas décadas del siglo XX, desde la constitución de un texto fundacional: el ensayo de Noé Jitrik titulado "Alturas de Machu Picchu. Una marcha piramidal a través de un discurso poético incesante". Posteriormente, se muestra en dos críticos destacados de una promoción posterior -Cristina Piña y Daniel Freidemberg- la coexistencia de tendencias opuestas en las elecciones estéticas, propias de las poéticas de los años sesenta y prolongadas hasta los ochenta, pero con la común característica del productivo procesamiento de la moderna teoría literaria.

Crítica y poesía. Elementos para una tradición

Este ensayo estudia las operaciones epistemológicas actuantes en la crítica argentina contemporánea de poesía, tomando en cuenta el estatuto teórico-filosófico de su discurso. Para ello, postula una tradición emergente en las últimas décadas del siglo XX, desde la constitución de un texto fundacional: el ensayo de Noé Jitrik titulado "Alturas de Machu Picchu. Una marcha piramidal a través de un discurso poético incesante". Posteriormente, se muestra en dos críticos destacados de una promoción posterior -Cristina Piña y Daniel Freidemberg- la coexistencia de tendencias opuestas en las elecciones estéticas, propias de las poéticas de los años sesenta y prolongadas hasta los ochenta, pero con la común característica del productivo procesamiento de la moderna teoría literaria.

Crítica y poesía. Elementos para una tradición

Este ensayo estudia las operaciones epistemológicas actuantes en la crítica argentina contemporánea de poesía, tomando en cuenta el estatuto teórico-filosófico de su discurso. Para ello, postula una tradición emergente en las últimas décadas del siglo XX, desde la constitución de un texto fundacional: el ensayo de Noé Jitrik titulado "Alturas de Machu Picchu. Una marcha piramidal a través de un discurso poético incesante". Posteriormente, se muestra en dos críticos destacados de una promoción posterior -Cristina Piña y Daniel Freidemberg- la coexistencia de tendencias opuestas en las elecciones estéticas, propias de las poéticas de los años sesenta y prolongadas hasta los ochenta, pero con la común característica del productivo procesamiento de la moderna teoría literaria.

Key reconciliation for high performance Quantum Key Distribution

Quantum Key Distribution is carving its place among the tools used to secure communications. While a difficult technology, it enjoys benefits that set it apart from the rest, the most prominent is its provable security based on the laws of physics. QKD requires not only the mastering of signals at the quantum level, but also a classical processing to extract a secret-key from them. This postprocessing has been customarily studied in terms of the efficiency, a figure of merit that offers a biased view of the performance of real devices. Here we argue that it is the throughput the significant magnitude in practical QKD, specially in the case of high speed devices, where the differences are more marked, and give some examples contrasting the usual postprocessing schemes with new ones from modern coding theory. A good understanding of its implications is very important for the design of modern QKD devices.

Hayek and complexity: coordination, evolution and methodology in social adaptive systems

The affinity between the work of the Austrian economist Friedrich A. Hayek and the approach of Complexity Economics is widely recognized by the literature. In spite of this, there still is a lack of studies that seek to analyze in depth the relationship between Hayek and complexity. This dissertation is a contribution to the filling of this large gap in the literature. In the first part of the work, we analyze the various periods in the development of Hayek\'s vision of complexity, showing that this vision is strongly present in his works on knowledge, competition, methodology, evolution, and spontaneous order. In the second part, we explore how Hayek was influenced by two of the main precursors of modern complexity theory - cybernetics and general system theory - from the time he was working on his book on theoretical psychology, The Sensory Order (1952), until the end of his intellectual career.

Análise de portfólio: uma perspectiva bayesiana

Este trabalho tem com objetivo abordar o problema de alocação de ativos (análise de portfólio) sob uma ótica Bayesiana. Para isto foi necessário revisar toda a análise teórica do modelo clássico de média-variância e na sequencia identificar suas deficiências que comprometem sua eficácia em casos reais. Curiosamente, sua maior deficiência não esta relacionado com o próprio modelo e sim pelos seus dados de entrada em especial ao retorno esperado calculado com dados históricos. Para superar esta deficiência a abordagem Bayesiana (modelo de Black-Litterman) trata o retorno esperado como uma variável aleatória e na sequência constrói uma distribuição a priori (baseado no modelo de CAPM) e uma distribuição de verossimilhança (baseado na visão de mercado sob a ótica do investidor) para finalmente aplicar o teorema de Bayes tendo como resultado a distribuição a posteriori. O novo valor esperado do retorno, que emerge da distribuição a posteriori, é que substituirá a estimativa anterior do retorno esperado calculado com dados históricos. Os resultados obtidos mostraram que o modelo Bayesiano apresenta resultados conservadores e intuitivos em relação ao modelo clássico de média-variância.

Essai critique sur l'hypothèse des atomes dans la science contemporaine,

"La première édition ... a été publiée dans les Annales de l'Université de Lyon, 1895."

Versuch einer genetischen Entwickelung der mechanischen Krystallisations-Gesetze : nebst vorläufigen Erörterungen über die mechanischen Bedingungen des dreifachen Aggregatzustandes der Körper überhaupt /

Mode of access: Internet.

Théorie des atomes et des équivalents chimiques: suivie d'une table très-étendue /

Includes index.