Integration of electric vehicles into distribution networks

The objectives of this research were to investigate the impact of electric vehicle battery charging on grid demand at a national level and on the steady state parameters of distribution networks. An agent-based control system that coordinates the battery charging of electric vehicles according to electric vehicle owner preferences, distribution network technical limits and electricity prices was designed and developed and its operation was tested experimentally. The impact on grid demand peak increases at the national systems of Great Britain and Spain was evaluated using low and high electric vehicle uptake levels of 7% and 48.5% of the car fleet for the year 2030 with a deterministic method. It was found that a low uptake will not raise significantly the grid demand peaks in both countries under investigation. However, a high uptake will raise significantly the grid demand peaks. The impact from residential electric vehicle battery charging on steady state voltages, power line losses, transformers’ and cables’ loadings of distribution networks was evaluated using a deterministic and a probabilistic method. It was found that low and medium uptake levels of electric vehicles equivalent to 12.5% and 33% per residential area of 384 customers in 2030, can be safely accommodated by reinforcing the distribution network. A combination of reinforcements, installation of microgenerators and control of electric vehicle battery charging will be required to accommodate safely a high uptake of 71% with regards to the constraints studied. An agent-based control system that coordinates the battery charging of electric vehicles was designed and developed. Search techniques and neural networks were used for the decision making processes. The ability of the agent-based control system to operate successfully in both normal and abnormal conditions for the electrical network was proved with experimental validation in the laboratory of Tecnalia research institute in Spain.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

The variation of the fine structure constant: testing the dipole model with thermonuclear supernovae

The large-number hypothesis conjectures that fundamental constants may vary. Accordingly, the space-time variation of fundamental constants has been an active subject of research for decades. Recently, using data obtained with large telescopes a phenomenological model in which the fine structure constant might vary spatially has been proposed. We test whether this hypothetical spatial variation of alpha, which follows a dipole law, is compatible with the data of distant thermonuclear supernovae. Unlike previous works, in our calculations we consider not only the variation of the luminosity distance when a varying alpha is adopted, but we also take into account the variation of the peak luminosity of Type Ia supernovae resulting from a variation of alpha. This is done using an empirical relation for the peak bolometric magnitude of thermonuclear supernovae that correctly reproduces the results of detailed numerical simulations. We find that there is no significant difference between the several phenomenological models studied here and the standard one, in which alpha does not vary spatially. We conclude that the present set of data of Type Ia supernovae is not able to distinguish the standard model from the dipole models, and thus cannot be used to discard nor to confirm the proposed spatial variation of alpha.Peer ReviewedPostprint (published version

Uma Interpretação Epistemológica do Processo de Modelagem Matemática: implicações para a matemática

Neste artigo, discutimos aspectos epistemológicos do processo de modelagem matemática motivados por uma análise da componente 'realidade' nesse processo. Descrições do processo de modelagem matemática, inspiradas pela matemática aplicada como método científico de pesquisa, são apresentadas, focando nelas a realidade a ser modelada, o que nos conduz em seguida a um desdobramento dessa componente do processo e subsequente análise epistemológica, diferenciando, notoriamente, a realidade inicial de uma pseudo-realidade, sendo, esta última, o objeto do conhecimento. Isso nos leva a uma releitura do referido processo, fundamentada em concepções de filosofia da ciência como realismo, estruturalismo e empirismo, que logo é adaptada ao estudo de situações matemáticas consideradas como a realidade inicial a ser modelada, permitindo uma visão semi-empírica da matemática, cujas consequências para a Educação Matemática são evidenciadas

La renovación de la palabra en el bicentenario de la Argentina : los colores de la mirada lingüística

El libro reúne trabajos en los que se exponen resultados de investigaciones presentadas por investigadores de Argentina, Chile, Brasil, España, Italia y Alemania en el XII Congreso de la Sociedad Argentina de Lingüística (SAL), Bicentenario: la renovación de la palabra, realizado en Mendoza, Argentina, entre el 6 y el 9 de abril de 2010. Las temáticas abordadas en los 167 capítulos muestran las grandes líneas de investigación que se desarrollan fundamentalmente en nuestro país, pero también en los otros países mencionados arriba, y señalan además las áreas que recién se inician, con poca tradición en nuestro país y que deberían fomentarse. Los trabajos aquí publicados se enmarcan dentro de las siguientes disciplinas y/o campos de investigación: Fonología, Sintaxis, Semántica y Pragmática, Lingüística Cognitiva, Análisis del Discurso, Psicolingüística, Adquisición de la Lengua, Sociolingüística y Dialectología, Didáctica de la lengua, Lingüística Aplicada, Lingüística Computacional, Historia de la Lengua y la Lingüística, Lenguas Aborígenes, Filosofía del Lenguaje, Lexicología y Terminología

The history of a forgotten town: Comacchio and its archaeology

Revisione dei dati pregressi e presentazione delle nuove risultanze per l'inquadramento storico-archeologico di Comacchio dalla fondazione ai primi secoli alto-medievali. Contestualizzazione di questo emporio adriatico nell'ambito dell'economia nord-italiana ed adriatica tra VII e X secolo