Search for dissertations about: "mode-matching"
Showing result 6 - 10 of 13 swedish dissertations containing the word mode-matching.
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6. Electronic Structure and Transport in Nanofabricated Low-Dimensional Semiconductor Systems : A theoretical study
Abstract : Systematic studies of the transport properties in one type of low-dimensional semiconductor nanostructures, in which the motion of carriers is governed by quantum mechanics, are presented in this thesis. In addition, the electronic states in lowdimensional systems fabricated from GaAs / Al?Ga1-?As heterostructures have been investigated by using both transport methods and the static calculations. READ MORE
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7. Twist-Symmetric Periodic Structures : Properties and Applications
Abstract : In this thesis, periodic structures with higher symmetries symmetries are discussed. The main focus of the thesis is on twist symmetries. Importantly, the attractive properties of twist symmetries for the control of electromagnetic wave propagation are demonstrated. READ MORE
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8. Online power transformer diagnostics using multiple modes of microwave radiation
Abstract : In the present thesis, we propose and investigate a new approach to diagnose the effects of the various degradation mechanisms, including thermal degradation at hot spots, winding deformations due to the mechanical forces from short circuit currents, partial discharges due to local electric field surges, and increased moisture levels in the cellulose insulation due to decomposition, that affect electric power transformers during their normal operation in an electric power grid.Although the proposed diagnostics method can in principle be used to detect various degradation mechanisms mentioned above, we focus in the present thesis on mechanical deformations of transformer winding structures. READ MORE
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9. Structure-borne sound properties of vibration isolators
Abstract : This thesis consists of four papers concerning the audibledynamic stiffness of a vibration isolator; includingmeasurements and theoretical modeling. The study focus isrubber isolators, being the most popular material in theaudible frequency domain - though the measurement principlealso applies to other resilient elements. READ MORE
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10. Stochastic model updating and model selection with application to structural dynamics
Abstract : Uncertainty induced by our incomplete state of knowledge about engineering systems and their surrounding environment give rise to challenging problems in the process of building predictive models for the system behavior. One such challenge is the model selection problem, which arises due to the existence of invariably multiple candidate models with different mathematical forms to represent the system behavior, and so there is a need to assess their plausibility based on experimental data. READ MORE