The discovery of metamaterials has led to major advances in different fields of physics including optics, microwave engineering and acoustics. Specific to theoretical electromagnetism, the introduction of metamaterials have led to the development of negative-index materials (NIMs) with simultaneous negative permittivity and negative permeability with backward-wave propagation. In recent studies, exact analytical solutions for wave propagation from a step/graded-index interface between a right-handed material (RHM) and a left-handed material (LHM) have been obtained. This study attempts to provide numerical validation of the analytical solutions obtained by Dalarsson et al. by using the simulation tool CST. An square-SRR/strip-wire unit element was designed, with real part of relative permittivity equal to -1.96 and real part of relative permeability equal to -1.01. Such unit elements were orderly structured to produce a NIM structure. Furthermore, a positive-index material (PIM) structure was produced by reversing the sign of the material properties of the NIM. Both the results for the step- and graded-index interfaces have shown to possess backward-wave propagation for a normal incidence angle. The graded-index interface profiles have a more smooth and continuous wave propagation between the materials, which counteracts the effects of discontinuous material transitions present in step-index interface profiles. However, because the results of the present study were considerably affected by unwanted field effects, the analytical solutions are only qualitatively validated, and not validated in terms of their numerical accuracy. / Upptäckten av metamaterial har lett till stora framsteg inom olika fysikområden inklusive optik, mikrovågsteknik och akustik. Specifikt för teoretisk elektromagnetism, har introduktionen av metamaterial lett till utvecklingen av negativa indexmaterial (NIM) med samtidig negativ permittivitet och negativ permeabilitet med bakåtvågsutbredning. I nyligen genomförda studier, har exakta analytiska lösningar för vågutbredning över ett steg-/graderat- indexgränssnitt mellan ett högerhänt material (RHM) och ett vänsterhänt material (LHM) erhållits. Denna studie försöker tillhanda-hålla numerisk validering, med hjälp av simuleringsverktyget CST, av de analytiska lösningar som erhållits av Dalarsson et al. En square-SRR/strip-wire enhetselement designades, med realdelen av relativ permittivitet lika med -1,96 och realdelen av relativ permeabilitet lika med -1,01. Sådana enhetselement strukturerades för att producera en materialstruktur med negativt index. Dessutom producerades en materialstruktur med positivt index (PIM) genom att vända tecknet av materialegenskaperna hos det negativa indexmaterialet (NIM). Både resultaten för steggränssnittet och det graderade indexgränssnittet har visat sig ha bakåtvågutbredning för vinkelrätt infall. De graderade indexgränssnittsprofilerna har en mer jämn och kontinuerlig vågutbredning mellan materialen, vilket motverkar effekterna av diskontinuerliga materialövergångar som finns i stegindexgränssnittsprofiler. Men eftersom resultaten av den aktuella studien påverkades avsevärt av oönskade fälteffekter, har de analytiska lösningarna validerats endast kvalitativt och valideras inte i termer av deras numeriska noggrannhet.

The diploma thesis deals with metamaterial structures. Metamaterials are periodic structures, which have got permittivity or permeability, eventually both parameters, negative. Test is applied on three basic structures: Split Loop Array; Spiral Array a Double Spiral Array. For each structure is made dispersion diagram and are monitored S – parameters. Test is run in Ansoft High Frequency Structure Simulator and CST Microwave Studio software. Are monitored bandgaps and when structure is as left – handed medium or right – handed medium. Results are compared with results in literature.

This dissertation investigates how cognates are organized in the bilingual mental lexicon and examines whether orthography in one language, via phonological representations, influences the processing of cognates and false friends in the other language. In light of the framework of two well-known models of bilingual visual word recognition, the Bilingual Interactive Activation (BIA) and the Bilingual Interactive Activation Plus (BIA+), the premise is that there is activation from orthography to phonology across a bilingual’s two languages and that this activation is modulated by the degree of orthographic and phonological code overlap. Two objective metrics were used to assess crosslinguistic similarity of Portuguese-English cognates and false friends that were selected for a cross-language lexical decision task with masked priming. Dynamic time warping (DTW), an algorithm that was originally conceived to compare different speech patterns in automatic speech recognition and to measure acoustic similarity between two time-dependent sequences, was used to compute crosslinguistic phonological similarity. The Normalized Levenshtein Distance (NLD), an algorithm that calculates the minimum number of single-character insertions, deletions or substitutions required to change one word into another and normalizes the result by their lengths, was used to compute crosslinguistic orthographic similarity. Portuguese-English bilinguals who acquired their second language after reaching puberty, and English functional monolinguals who grew up speaking primarily English were recruited to participate in the experimental task. Based on collected reaction time and accuracy data, mixed-effects models analyses are used to estimate the individual effects of crosslinguistic orthographic, phonological and semantic similarity and the role each of them, along with English proficiency, word frequency and length play in the organization of the Portuguese-English bilingual mental lexicon.

El uso de la Realidad Virtual dentro del campo de la Rehabilitaci on Motora en pacientes con Da~no Cerebral Adquirido (DCA) es un hecho cient camente contrastado en los ultimos a~nos. Los prometedores y satisfactorios resultados que se est an obteniendo en esta l nea de investigaci on (tanto a nivel cognitivo, como a nivel motor), en conjunci on con los procesos terap euticos tradicionales, proporcionan el auge de un nuevo hito dentro de la rehabilitaci on tradicional conocido como Virtual Motor Rehabilitation cuyo acr onimo es (VMR), describi endolo como Rehabilitaci on Virtual Motora (RVM). Hoy en d a, el Da~no Cerebral Adquirido es uno de los principales problemas de discapacidad y muerte en el mundo, donde las metodolog as propuestas dentro del campo de la rehabilitaci on tradicional, proporcionan resultados prometedores y esperanzadores. No obstante, este tipo de terapias presentan inconvenientes como son la falta de motivaci on del paciente, que lleva a una limitada adherencia al tratamiento, o las limitaciones de tiempo, espacio o coste que surgen en el proceso rehabilitador. Tradicionalmente, los principales experimentos realizados dentro del campo de la Rehabilitaci on Motora, se han realizado en pacientes DCA post-agudos y agudos, con escasas publicaciones basadas en el proceso rehabilitador motor de pacientes DCA cr onicos. En la presente tesis se han desarrollado sistemas de Rehabilitaci on Virtual para que, gracias al uso de dispositivos de bajo coste y las aportaciones obtenidas por los especialistas cl nicos, se haya validado la hip otesis: Mediante t ecnicas de rehabilitaci on virtual es posible obtener en pacientes cr onicos una recuperaci on del equilibrio estad sticamente signi- cativa, y similar a la que es posible obtener en pacientes agudos. Los experimentos realizados en el proceso rehabilitador, junto con las validaciones cl nicas realizadas en el Hospital Valencia al Mar, y el Instituto Valenciano de la Discapacidad, han servido para obtener unos resultados contrastables y satisfactorios, que corroboran la hip otesis de trabajo planteada. / Albiol Pérez, S. (2014). Rehabilitación Virtual Motora: una Evaluación al tratamiento de pacientes con Daño Cerebral Adquirido [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/38450