In this thesis, the dynamics of two plates overlapping and connected by three bolts are studied. The data collected in the test are used in modal analysis. The vibrational test and the modal analysis were made using an LMS system. Hammer excitation is used for the tests. The main purpose of this thesis is to study how the suspensions affect the extracted eigenfrequencies and modal dampings. In this thesis, more than 10 suspensions were examined. Another objective in this thesis work is to build an FE-model. This model is made using the software Abaqus. To improve the reliability of the FE-model, a set of reliable experimental data is used to calibrate the model. The calibrated FE-model, using the measurement data, has a dynamic behavior close to the measurement data.

Chapter 1 introduces the notions of multisensory integration (the binding of information coming from different modalities into a unitary percept) and multisensory response enhancement (the improvement of the response to multisensory stimuli, relative to the response to the most efficient unisensory stimulus), as well as the general goal of the present thesis, which is to investigate different aspects of the multisensory integration of auditory and visual stimuli in manual and saccadic responses. The subsequent chapters report experimental evidence of different factors affecting the multisensory response: spatial discrepancy, stimulus salience, congruency between cross-modal attributes, and the inhibitory influence of concurring distractors. Chapter 2 reports three experiments on the role of the superior colliculus (SC) in multisensory integration. In order to achieve this, the absence of S-cone input to the SC has been exploited, following the method introduced by Sumner, Adamjee, and Mollon (2002). I found evidence that the spatial rule of multisensory integration (Meredith & Stein, 1983) applies only to SC-effective (luminance-channel) stimuli, and does not apply to SC-ineffective (S-cone) stimuli. The same results were obtained with an alternative method for the creation of S-cone stimuli: the tritanopic technique (Cavanagh, MacLeod, & Anstis, 1987; Stiles, 1959; Wald, 1966). In both cases significant multisensory response enhancements were obtained using a focused attention paradigm, in which the participants had to focus their attention on the visual modality and to inhibit responses to auditory stimuli. Chapter 3 reports two experiments showing the influence of shape congruency between auditory and visual stimuli on multisensory integration; i.e. the correspondence between structural aspects of visual and auditory stimuli (e.g., spiky shape and “spiky” sounds). Detection of audio-visual events was faster for congruent than incongruent pairs, and this congruency effect occurred also in a focused attention task, where participants were required to respond only to visual targets and could ignore irrelevant auditory stimuli. This particular type of cross-modal congruency was been evaluated in relation to the inverse effectiveness rule of multisensory integration (Meredith & Stein, 1983). In Chapter 4, the locus of the cross-modal shape congruency was evaluated applying the race model analysis (Miller, 1982). The results showed that the violation of the model is stronger for some congruent pairings in comparison to incongruent pairings. Evidence of multisensory depression was found for some pairs of incongruent stimuli. These data imply a perceptual locus for the cross-modal shape congruency effect. Moreover, it is evident that multisensoriality does not always induce an enhancement, and in some cases, when the attributes of the stimuli are particularly incompatible, a unisensory response may be more effective that the multisensory one. Chapter 5 reports experiments centred on saccadic generation mechanisms. Specifically, the multisensoriality of the saccadic inhibition (SI; Reingold&Stampe, 2002) phenomenon is investigated. Saccadic inhibition refers to a characteristic inhibitory dip in saccadic frequency beginning 60-70 ms after onset of a distractor. The very short latency of SI suggests that the distractor interferes directly with subcortical target selection processes in the SC. The impact of multisensory stimulation on SI was studied in four experiments. In Experiments 7 and 8, a visual target was presented with a concurrent audio, visual or audio-visual distractor. Multisensory audio-visual distractors induced stronger SI than did unisensory distractors, but there was no evidence of multisensory integration (as assessed by a race model analysis). In Experiments 9 and 10, visual, auditory or audio-visual targets were accompanied by a visual distractor. When there was no distractor, multisensory integration was observed for multisensory targets. However, this multisensory integration effect disappeared in the presence of a visual distractor. As a general conclusion, the results from Chapter 5 results indicate that multisensory integration occurs for target stimuli, but not for distracting stimuli, and that the process of audio-visual integration is itself sensitive to disruption by distractors.

This work explores the interaction of electromagnetic radiation with periodic metal-dielectric composite materials. In particular, the majority of the studies explore the role of evanescent diffraction in the regime where the wavelength of the incident radiation is of the order of the period of the array just below the onset of diffraction. The underlying aim of the thesis is to build on the current knowledge and gain deeper understanding into the causal mechanism of the electromagnetic response of these periodic materials. Developments in metamaterial research have led to a resurgance of interest in the use of periodic metallic surface to control the transmission of electromagnetic radiation. The response of these surfaces can be `tuned' to provide the required response simply by altering the geometric parameters of the material. Numerical modelling techniques are often used to predict the response of such structures. However, the aim of this work is to gain a deeper understanding of the reasons for the response and therefore an analytical modal matching method has been used. The modal matching method provides the opportunity to extract greater understanding of the resonant phenomena by linking them to specific mathematical terms in the analytical formulation. The modal matching technique is initially used to study the response from a single layer bigrating comprising a square array of square holes in a PEC sheet and its complementary system of a square array of square PEC patches. The importance of evanescent diffraction in both resonant phenomena and tunneling responses is discussed and it is shown that complete transmission (reflection) is supported by these structures even for very high (low) metal occupancy. This technique is extended and adapted to describe a variety of structures in chapters 5 and 6, exploring how resonant excitation of surface waves via evanescent diffraction leads to highly interesting electromagnetic responses. In chapter 7, alternating multilayer stacks of two different subwavelength meshes provide an observable one-dimensional topological mode in a physical system for particular mesh configurations.

Ingeniero Civil Electricista / Los sistemas eléctricos de potencia (SEP) cada día se encuentran más exigidos, en tanto el crecimiento de la demanda últimamente aumenta a mayor tasa que las inversiones en el rubro. Esto ha obligado a que la operación de estos sea cada vez más cerca de sus límites de estabilidad. Verificar la respuesta en el tiempo de un sistema dinámico tan grande, a la vez para miles de perturbaciones posible resulta una tarea titánica, por lo cual el análisis transitorio de estabilidad se reserva solo para contingencias críticas. En cambio, para las contingencias de menor importancia y que pueden calificar dentro de la categoría de perturbación, basta con un análisis de estabilidad de pequeña señal. Los estudios de pequeña señal permiten identificar los modos de oscilación para todo un conjunto de perturbaciones pequeñas, con un menor esfuerzo computacional, aunque a costa de una menor precisión. Reconocer los modos de oscilación de un sistema permite identificar aquellos inestables o de bajo amortiguamiento, para así tomar decisiones de inversión en transmisión que mejoren esta situación, pero incluso, últimamente se está utilizando el reconocimiento modal para la ejecución de acciones en tiempo real que permitan controlar las oscilaciones, por lo que el estudio de pequeña señal aún resulta ser un campo con aplicaciones industriales relevantes, sobre todo ahora que los sistemas de comunicaciones permiten recopilar la información de toda la red de manera rápida y confiable. En este trabajo se busca en primer lugar, validar la utilización de los modelos de pequeña señal, comparando la respuesta transitoria de sistemas de prueba contra la linealización del mismo. Luego, se procede a identificar las variables más relevantes y que aportan en mayor medida a las oscilaciones e inestabilidades del sistema, para finalmente aplicar un estudio de análisis modal a un caso real, mediante el modelamiento simplificado del Sistema Interconectado Central chileno. En este contexto, se analiza el escenario presente, y un escenario con nuevas inversiones en transmisión, para verificar si existe algún impacto en los modos de oscilación naturales del sistema. Además se estudia el efecto de la variación en el escenario de generación, incrementando la diferencia angular entre barras del sistema. Por último, se incluye un análisis de sensibilidad para todos los casos estudiados, determinando la ubicación del valor propio de menor amortiguación en el plano complejo, frente a contingencias e inversiones en elementos serie de la red de trasmisión. Los resultados concluyen que el efecto de la red de transmisión es acotado en mejorar la estabilidad, impactando solo de manera puntual a algunos valores propios, pudiendo una misma acción (inversión o contingencia) empeorar o mejorar el amortiguamiento de las oscilaciones electromecánicas.

A concurrent system is a computer system with components that run in parallel and interact with each other. Such systems are ubiquitous and are notably responsible for supporting the infrastructure for transport, commerce and entertainment. They are very difficult to design and implement correctly: many different modeling languages and verification techniques have been devised to reason about them and verifying their correctness. However, existing languages and techniques can only express a limited range of systems and properties. In this dissertation, we address some of the shortcomings of established models and theories in four ways: by introducing a general modal logic, extending a modelling language with types and a more general operation, providing an automated tool support, and adapting an established behavioural type theory to specify and verify systems with unreliable communication. A modal logic for transition systems is a way of specifying properties of concurrent system abstractly. We have developed a modal logic for nominal transition systems. Such systems are common and include the pi-calculus and psi-calculi. The logic is adequate for many process calculi with regard to their behavioural equivalence even for those that no logic has been considered, for example, CCS, the pi-calculus, psi-calculi, the spi-calculus, and the fusion calculus. The psi-calculi framework is a parametric process calculi framework that subsumes many existing process calculi. We extend psi-calculi with a type system, called sorts, and a more general notion of pattern matching in an input process. This gives additional expressive power allowing us to capture directly even more process calculi than was previously possible. We have reestablished the main results of psi-calculi to show that the extensions are consistent. We have developed a tool that is based on the psi-calculi, called the psi-calculi workbench. It provides automation for executing the psi-calculi processes and generating a witness for a behavioural equivalence between processes. The tool can be used both as a library and as an interactive application. Lastly, we developed a process calculus for unreliable broadcast systems and equipped it with a binary session type system. The process calculus captures the operations of scatter and gather in wireless sensor and ad-hoc networks. The type system enjoys the usual property of subject reduction, meaning that well-typed processes reduce to well-typed processes. To cope with unreliability, we also introduce a notion of process recovery that does not involve communication. This is the first session type system for a model with unreliable communication.

Visual deprivation in early life causes widespread changes to the visual pathway. Structures normally dedicated to vision can be recruited for processing of the remaining senses (i.e. audition). This thesis used magnetic resonance imaging to explore how the 'visual' pathway reorganises in congenital bilateral anophthalmia, a condition where individuals are born without eyes. Anophthalmia provides a unique model of complete deprivation, since the ‘visual’ pathway has not experienced pre- or post-natal visual input. Firstly, this thesis explored reorganisation of the anophthalmic 'visual' pathway for auditory processing, from subcortical structures responding to basic sounds (Chapters 3 and 4), to higher-order occipital areas extracting meaning from speech sounds (Chapter 7). Secondly, this thesis looked to better understand the neurochemical, neuroanatomical and behavioural changes that accompany reorganisation in anophthalmia (Chapters 5 and 6). Finally, this thesis investigated whether similar changes can take place in the sighted brain after a short period of visual deprivation (Chapter 8). The experiments in this thesis provide some evidence that the lack of pre-natal visual experiences affects cross-modal reorganisation. Chapter 4 describes a unique subcortico-cortical route for auditory input in anophthalmia. Furthermore, Chapter 7 suggests that hierarchical processing of sensory information in the occipital cortex is maintained in anophthalmia, which may not be the case in congenital or early-onset blindness. However, this thesis also suggests that some reorganisation thought to be limited to anophthalmia can be found in early-onset blindness, for example with the subcortical functional changes described in Chapter 3. In addition, neurochemical, neuroanatomical and behavioural changes described in Chapters 5 and 6 are comparable to those reported in early-onset blindness, therefore demonstrating important similarities between these populations. Finally, this thesis describes how some of these functional and behavioural changes can also take place in sighted subjects after a short period of blindfolding, although this effect is extremely variable across subjects (Chapter 8). The thesis concludes by highlighting the considerable contribution of individual differences in studies of cross-modal reorganisation, and emphasises the need for larger more homogenous groups when investigating subcortical and cortical plasticity in the absence of visual input.

The aim of this thesis is to examine the current Dutch modal particles and ascertain if this word class is fully translatable into Czech and Slovak language. The first, theoretical part of this thesis focuses primarily on the Dutch modal particles as such; explains what is modality, classifies particles as a word class, describes the characteristics of modal particles, which specific words are considered as modal particles, what kinds of modal particles exist in the Dutch language and what are their attributes both from a pragmatic and syntactic perspective. The theoretical part explains in detail the ways in which modality is expressed in Czech and Slovak, what kinds of particles in these two languages exist, and if there exist modal particles, which words are considered as these. In the conclusion of the theoretical part of the thesis is summarized what do have these three languages in common in this area, whether by the term modal particles is understood the same word class in each of these languages and whether it appears that the Dutch modal particles do have in Czech and Slovak their exact equivalents and are therefore fully translatable into these two languages. This claim will be verified in the practical part of the thesis. In the second, practical part of the thesis are the Dutch modal...

Ingeniero Civil Mecánico / La Comisión Chilena de Energía Nuclear (CCHEN), cuenta con un reactor de investigación de 5 [MWt] y fabrica los elementos combustibles (EC) tipo MTR para su operación en la Planta Elemento Combustible (PEC). Es un objetivo estratégico diseñar y fabricar nuevos diseños de EC para clientes en el extranjero, por lo que se propone aumentar la capacidad de diseño de la planta. Para estos nuevos diseños se debe verificar su comportamiento mecánico, siendo fundamental para la operación conocer el comportamiento del prototipo ante vibraciones externas. El objetivo general de la memoria persigue diseñar una bancada de ensayos de vibración para verificación mecánica del diseño del Elemento Combustible MTR y de nuevos diseños, mediante ensayos en ambiente seco (al aire). Los objetivos específicos se estructuran según nivel de complejidad, comenzando con la Ingeniería Conceptual, que permita identificar los requerimientos de implementación y operación. Se sigue con la Ingeniería Básica, que abarca pruebas experimentales, definición de criterios y parámetros de diseño y elaboración de memorias de cálculo y planos preliminares. Culmina la fase de diseño con la Ingeniería de Detalle, mediante la preparación de planos de fabricación de la estructura y definición de elementos comerciales, basados en las correspondientes memorias de cálculo definitivas. Finalmente, se determina el presupuesto para la fabricación e implementación de la bancada de ensayos de vibración. La metodología utilizada consiste en la elaboración de un bosquejo preliminar de la solución en base al levantamiento de información, para posteriormente entrar en un proceso iterativo de diseño y memorias de cálculo, alimentado con los resultados obtenidos de los ensayos de análisis modal experimental aplicados al modelo de EC MTR placas planas. El cálculo se basa en simulaciones de análisis modal mediante ANSYS, aplicación de las normas NCh 427 para la estructura y NCh 170-2016 para el diseño en hormigón. Una vez alcanzado el diseño final, se obtienen como entregables el modelo CAD, diseñado en Inventor, los planos general, de despiece y fabricación, el diagrama de instrumentación P&ID y un análisis económico. Finalmente, los lineamientos proyectados se cumplen a cabalidad, culminando con el modelo CAD, la elaboración de planos de fabricación, construcción e instrumentación, memorias de cálculo estructural y de análisis modal, presupuesto y análisis económico. El estudio concluye con propuestas de modificación y trabajo futuro, con miras a la implementación de la bancada, interacción con nuevos proyectos y estudios complementarios que aporten al desarrollo del diseño de EC MTR. / Este trabajo ha sido parcialmente financiado por la Comisión Chilena de Energía Nuclear (CCHEN)

Esta pesquisa apresenta um estudo investigativo da análise modal aplicada a Sistemas de Distribuição (SDs) frente às distorções harmônicas, no contexto da Qualidade da Energia Elétrica (QEE). A partir do método de análise da ressonância modal, foi conduzido um estudo investigativo para apontar quais barramentos são mais sensíveis e permitem uma melhor observação frente às distorções harmônicas. Vale adiantar que o método de análise de ressonância modal, o qual é fundamentado na decomposição espectral da matriz de admitância do sistema elétrico, já apresenta interessantes trabalhos voltados para sistemas de transmissão. O desafio desta pesquisa foi então investigar a sua aplicação para SDs com um direcionamento às distorções harmônicas, bem como ao seu monitoramento. Dentre os resultados encontrados no desenvolvimento da pesquisa, destaca-se um melhor entendimento do problema das distorções harmônicas, o qual permitiu evidenciar a sensibilidade e a observabilidade dos SDs testes frente ao problema definido no contexto da QEE. / This research presents an investigative study of the modal analysis applied to Distribution Systems (DSs) in the context of Power Quality (PQ) considering the harmonic distortions. From the modal resonance analysis, an investigative study was conducted to indicate which bus bars are more sensitive and allow better observation in face of harmonic distortions. It is worth mentioning that the method of modal resonance analysis, which is based on the spectral decomposition of the admittance matrix of the electric system, already presents interesting applications focused on transmission systems. The challenge of this research was to investigate its application to DSs focusing on harmonic distortions, as well as their monitoring. Among the observed results of the research development, a better understanding of the harmonic distortions problem was achieved, which made it possible to highlight the sensitivity and observability of the DSs tests against the problem defined in the context of the PQ.

This study represents an attempt to make explicit, within a contrastive perspective, the various types of meaning which can be expressed by the modal auxiliary verbs of English and Afrikaans. Chapter 1 investigates the potential of contrastive analysis for application in the field of foreign-language teaching and it is found that this linguistic technique is of definite pedagogical relevance because negative learning transfer or interference, which results from differences between source and target languages, is a major cause of learner error. It is also noted here that generally speaking the most acceptable type of linguistic theory within which a contrastive analysis should be framed is one which recognises both surface and deeper levels of structure so that the surface forms in each language can be ultimately related to a common semantic base. The modal auxiliaries of the two languages were selected for study because of the high degree of formal similarity or congruence that obtains between the English and Afrikaans counterparts, a fact which can be expected to lead to a considerable amount of learning transfer. As the semantics of these forms is not always equivalent, however, some of this transfer is bound to be negative, i.e. error-generating. In Chapter 2 the syntactic and morphological characteristics of the English and Afrikaans forms are compared. Although, as Chapter 2 reveals, the modal auxiliaries constitute a fairly well-defined formal class in each language, they relate semantically to an extensive set of other expressions, all of which mark modality, a rather complex concept which may be broadly characterised as relating to qualifications on the truth-value of the basic proposition which a speaker expresses. In Chapter 3 various classifications of types of modality are discussed and a basic distinction is made between epistemic modality (qualification relates directly to the speaker's assessment of the factuality of the proposition expressed) and non-epistemic modality (qualifications relate more specifically to conditions on the process referred to). In both cases the 11 qualification" can be expressed as a kind of "possibility" or a kind of "necessity", and within the framework of our analysis modality is represented at the level of deep-semantic structure by POSS and NEC as higher abstract predicates linked to one another by a set of meaning postulates. The interpretation of these predicates depends on the kinds of arguments which accompany them in the semantic representation and these arguments are classified and labelled broadly in accordance with Fillmore's functionalsemantic definitions of "case". The modal abstract predicates take as arguments a predication which is labelled as a Goal and either an Agent or Instrument as a source. Unlike traditional "modal operators", then, they are two-place transitive-causative predicates and the basic structure of the modal content of sentences is seen to be something of the order of "x makes-possible/necessary y (pre di ca ti on)". . Representations of epistemic modality contain a further BELIEVE predicate as part of the Goal predication. Depending on the prelexical transformations that apply (e.g. whether the modality source is deleted or not) syntactically different modality markers are derived from the same basic semantic representation and so expressions such as John allows Fred ... ,Fred is allowed ... and Fred can ... are shown to be broadly synonymous. Our main concern here is not with the actual transformations but with the "semantic primitives" in terms of which different types of modality may be represented and related to one another. Using the framework outlined in Chapter 3, the semantics of the "possibility" and the "necessity" modal auxiliaries in each language is discussed in Chapters 4 and 5 respectively. Both non-oblique ("present") and oblique ("imperfect") forms are related to one another and to other modality markers. Chapter 6 deals briefly with negative forms of the modal auxiliaries before summarising the semantic similarities and contrasts between the congruent English and Afrikaans forms. It is found that in spite of considerable parallelism in the meaning-form relations expressed by the modal auxiliaries in the two languages, there are also a number of basic differences. The pedagogical implications and applications relating to this study, its findings and its approach, are reviewed briefly by way of conclusion. / Linguistics and Modern Languages