abstract: Oxygen fugacity (ƒO2) is a thermodynamic variable used to represent the redox state of a material or a system. It is equivalent to the partial pressure of oxygen in a particular environment corrected for the non-ideal behavior of the gas. ƒO2 is often used to indicate the potential for iron to occur in a more oxidized or reduced state at a particular temperature and pressure in a natural system. Secondary ion mass spectrometry (SIMS) is a powerful analytical instrument that can be used to analyze elemental and isotopic compositional information about microscopic features within solid materials. SIMS analyses of the secondary ion energy distribution of semi-pure metals demonstrate that the energy spectrum of individual mass lines can provide information about alterations in its surface environment. The application of high-resolution (see Appendix C) energy spectrum calibrations to natural ilmenite led to the investigation of zirconium (90Zr+) and niobium (93Nb+) as potential indicators of sample ƒO2. Energy spectrum measurements were performed on an array of ilmenite crystals from the earth’s upper mantle retrieved from kimberlites and from a reduced meteorite. In all studied materials, variability in the peak shape and width of the energy spectra has been correlated with inferred sample ƒO2. The best descriptor of this relationship is the full-width at half-maximum (FWHM; see Appendix C) of the energy spectra for each sample. It has been estimated that a 1eV change in the FWHM of 93Nb+ energy spectra is roughly equivalent to 1 log unit ƒO2. Simple estimates of precision suggest the FWHM values can be trusted to  1eV and sample ƒO2 can be predicted to ±1 log unit, assuming the temperature of formation is known. The work of this thesis also explores the applicability of this technique beyond analysis of semi-pure metals and ilmenite crystals from kimberlites. This technique was applied to titanium oxides experimentally formed at known ƒO2 as well as an ilmenite crystal that showed compositional variations across the grain (i.e., core to rim chemical variations). Analyses of titanium oxides formed at known ƒO2 agree with the estimation that 1 eV change in the FWHM of 93Nb+ is equivalent to ~1 log unit ƒO2 (in all cases but one); this is also true for analyses of a natural ilmenite crystal with compositional variations across the grain. / Dissertation/Thesis / Masters Thesis Geological Sciences 2019

A presente pesquisa busca analisar e comparar as peças All My Sons [Todos Eram Meus Filhos] (1947) e An Enemy of the People [Um Inimigo do Povo] (1951), do dramaturgo norte-americano Arthur Miller (19152005). Em dois momentos cruciais da história norte-americana (o pósguerra e o macarthismo, respectivamente) Miller recorre ao dramaturgo norueguês Henrik Ibsen (1828 1906) para responder artistica e politicamente a essas situações. Tal resposta teve um forte impacto na estrutura formal dessas peças em um período no qual Arthur Miller pensava em desistir de ser dramaturgo. Em All My Sons, a Técnica Analítica, teorizada por Peter Szondi em Teoria do Drama Moderno, coloca no palco o passado e sua análise como elementos essenciais de ação, contradizendo fundamentalmente os princípios rigorosos do drama. A estrutura Greco-Ibseniana presente na peça é também um dos recursos pelos quais a peça alcança um efeito singular no qual forma e conteúdo interagem dialeticamente e contribuem para que Arthur Miller ocupe uma posição de destaque entre os dramaturgos norte-americanos. Em An Enemy of the People, Miller recorre novamente a Ibsen de maneira mais direta, sendo esta peça originalmente escrita pelo próprio norueguês e reescrita/adaptada por Arthur Miller no contexto do macarthismo. Sua forma, segundo teoriza Raymond Williams em Tragédia Moderna, é a da Tragédia Liberal cuja marca mais essencial é a de discutir a luta do homem contra sua sociedade. As aproximações e distanciamentos entre ambas as versões (a de Ibsen e a de Miller) levarão a uma reflexão sobre o tipo de adaptação que Arthur Miller buscou fazer e como isso representou um avanço formal. O estudo e a elucidação do processo formal em que ambas as peças estão ancoradas, apontam para uma fusão dos ideais de Miller enquanto escritor e cidadão e que ajudaram a revolucionar o teatro norte-americano. Ao escrever tais peças, Miller atesta a necessidade de se pensar e refletir trazendo a fúria, a lucidez e a coerência de Henrik Ibsen para o olho do furacão nos Estados Unidos. / The research focuses on the analysis and comparison of the plays All My Sons (1947) and An Enemy of the People (1951), by American playwright Arthur Miller (19152005). In two crucially important moments of American History (PostWar period and McCarthyism, respectively) Miller turns to Norwegian playwright Henrik Ibsen (18281906) to respond both artistically and politically to these situations. Such a response had a strong impact on the formal structure of the plays at a time in which Arthur Miller was almost giving up on being a dramatist. In All My Sons, the Analytical Technique, theorized by Peter Szondi in Theory of Modern Drama, places the past and its analysis on stage as essential elements of action, fundamentally contradicting the strict principles of drama. The Greco-Ibsen structure present in the play is also one of the elements that helps the play reach a remarkable effect in which form and content interact dialectically and contribute to exalt Arthur Millers position as a singular figure among other American dramatists. In An Enemy of the People, Miller turns to Ibsen once again in a direct way by choosing this play which had been originally written by the Norwegian playwright himself and now adapted by Arthur Miller in the context of McCarthyism. Its form, according to what Raymond Williams says in Modern Tragedy, is that of the Liberal Tragedy whose most essential mark is to discuss the struggle of man against his own society. The proximities and detachments between both versions (Ibsens and Millers) will lead to some reflection about which kind of adaptation Arthur Miller tried to have and how it endorsed a formal advance. The study and elucidation of the formal process in which both plays are rooted, point out to a merging of Millers ideals as a writer and citizen which helped revolutionize the American theater. By writing such plays, Miller attests the need to think and reflect, bringing the fury, the lucidity and the coherence of Henrik Ibsen to the eye of the storm within the United States

A presente pesquisa busca analisar e comparar as peças All My Sons [Todos Eram Meus Filhos] (1947) e An Enemy of the People [Um Inimigo do Povo] (1951), do dramaturgo norte-americano Arthur Miller (19152005). Em dois momentos cruciais da história norte-americana (o pósguerra e o macarthismo, respectivamente) Miller recorre ao dramaturgo norueguês Henrik Ibsen (1828 1906) para responder artistica e politicamente a essas situações. Tal resposta teve um forte impacto na estrutura formal dessas peças em um período no qual Arthur Miller pensava em desistir de ser dramaturgo. Em All My Sons, a Técnica Analítica, teorizada por Peter Szondi em Teoria do Drama Moderno, coloca no palco o passado e sua análise como elementos essenciais de ação, contradizendo fundamentalmente os princípios rigorosos do drama. A estrutura Greco-Ibseniana presente na peça é também um dos recursos pelos quais a peça alcança um efeito singular no qual forma e conteúdo interagem dialeticamente e contribuem para que Arthur Miller ocupe uma posição de destaque entre os dramaturgos norte-americanos. Em An Enemy of the People, Miller recorre novamente a Ibsen de maneira mais direta, sendo esta peça originalmente escrita pelo próprio norueguês e reescrita/adaptada por Arthur Miller no contexto do macarthismo. Sua forma, segundo teoriza Raymond Williams em Tragédia Moderna, é a da Tragédia Liberal cuja marca mais essencial é a de discutir a luta do homem contra sua sociedade. As aproximações e distanciamentos entre ambas as versões (a de Ibsen e a de Miller) levarão a uma reflexão sobre o tipo de adaptação que Arthur Miller buscou fazer e como isso representou um avanço formal. O estudo e a elucidação do processo formal em que ambas as peças estão ancoradas, apontam para uma fusão dos ideais de Miller enquanto escritor e cidadão e que ajudaram a revolucionar o teatro norte-americano. Ao escrever tais peças, Miller atesta a necessidade de se pensar e refletir trazendo a fúria, a lucidez e a coerência de Henrik Ibsen para o olho do furacão nos Estados Unidos. / The research focuses on the analysis and comparison of the plays All My Sons (1947) and An Enemy of the People (1951), by American playwright Arthur Miller (19152005). In two crucially important moments of American History (PostWar period and McCarthyism, respectively) Miller turns to Norwegian playwright Henrik Ibsen (18281906) to respond both artistically and politically to these situations. Such a response had a strong impact on the formal structure of the plays at a time in which Arthur Miller was almost giving up on being a dramatist. In All My Sons, the Analytical Technique, theorized by Peter Szondi in Theory of Modern Drama, places the past and its analysis on stage as essential elements of action, fundamentally contradicting the strict principles of drama. The Greco-Ibsen structure present in the play is also one of the elements that helps the play reach a remarkable effect in which form and content interact dialectically and contribute to exalt Arthur Millers position as a singular figure among other American dramatists. In An Enemy of the People, Miller turns to Ibsen once again in a direct way by choosing this play which had been originally written by the Norwegian playwright himself and now adapted by Arthur Miller in the context of McCarthyism. Its form, according to what Raymond Williams says in Modern Tragedy, is that of the Liberal Tragedy whose most essential mark is to discuss the struggle of man against his own society. The proximities and detachments between both versions (Ibsens and Millers) will lead to some reflection about which kind of adaptation Arthur Miller tried to have and how it endorsed a formal advance. The study and elucidation of the formal process in which both plays are rooted, point out to a merging of Millers ideals as a writer and citizen which helped revolutionize the American theater. By writing such plays, Miller attests the need to think and reflect, bringing the fury, the lucidity and the coherence of Henrik Ibsen to the eye of the storm within the United States

Les structures mécaniques utilisées de nos jours ne cessent d’évoluer en utilisant des matériaux composites ou à gradient fonctionnel afin de répondre aux enjeux de résistance accrue, allégement de la structure et amélioration des performances. Ceux-ci nécessitent un contrôle adéquat de leur état de santé afin de s’assurer de l’intégrité de la structure. L’utilisation des ondes guidées ultrasonores fournit un moyen efficace et rapide d’inspection sur de longues distances. Néanmoins, ces ondes présentent certaines caractéristiques complexes qui rendent la tâche très difficile. L’utilisation d’outils d’analyse tels que les modèles numériques constitue un grand atout pour ce type d’application. Dans ce contexte, l’objectif de cette de thèse est le développement d’un outil de modélisation performant, permettant d’étudier la propagation des ondes guidées ultrasonores avec une grande précision et une faible consommation de ressources et de temps de calculs. De ce fait, l’intérêt est porté sur des méthodes numériques d’ordres élevés dont les propriétés de convergence sont beaucoup améliorées que les méthodes classiques. En particulier, la méthode semi-analytique éléments finis de Galerkin discontinue pour la détermination des courbes de dispersion des ondes guidées est développée. La méthode est applicable aux structures planes et cylindriques fabriquées de matériaux isotropes, anisotropes et hétérogènes (à gradient fonctionnel de propriétés). Une étude comparative sur l’analyse des performances de ces méthodes est effectuée. Celle-ci a démontré la capacité de la méthode à modéliser la propagation des ondes guidées ultrasonores dans des guides d’ondes à section arbitraire avec des performances prometteuses par rapport à la méthode des éléments finis classique. / The mechanical structures used today are constantly evolving using composite or functionally gradient materials to meet the challenges of increased strength, lightening the structure and improving performance. These require adequate control of their state of health to ensure the integrity of the structure. The use of Ultrasound Guided Waves (UGW) provides an efficient and fast way of inspection over long distances. Nevertheless, these waves have some complex features that make the task very difficult. The use of analysis tools such as numerical models is a great asset for this type of application. In this context, the objective of this thesis is the development of a powerful modeling tool, allowing to study the propagation of UGWs with a great precision, less computational time and consumption of resources. Accordingly, we are interested in higher order numerical methods whose convergence properties are much improved than the classical methods. In particular, a semi-analytical discontinuous Galerkin finite element method (SADG-FE) is developped for the determination of the dispersion properties of guided waves in arbitrary cross-section waveguides. The method is applicable to plates and cylindrical structures made of isotropic, anisotropic heterogeneous (functionally graded) materials. The performance analysis of these methods and their comparisons are performed with respect to the models based on the classical finite element method. The results demonstrated the ability of the proposed method to model the propagation of ultrasounic guided waves in arbitrary section waveguides with promising performance over the conventional finite element method.

The power distribution system is the final link to transfer the electrical energy to the individual customers. It is distributed in a complex technical grid but is associated with the majority of all outages occurring. Improving its reliability is an efficient way to reduce the effects of outages. A common way of improving the reliability is by designing loop structures containing two connected feeders separated by a section point. The location of the section point will decide how the system structure is connected and its level of reliability. By finding the optimal location, an improved reliability may be accomplished. This Master’s thesis has developed a method of finding optimized section points locations in a primary distribution system in order to improve its reliability. A case study has been conducted in a part of Mälarenergi Elnät’s distribution system with the objective of developing an algorithm in MATLAB able to generate the optimal section points in the area. An analytical technique together with a method called Failure Modes and Effect Analysis (FMEA) as preparatory step, was used to simulate the impact of outages in various components based on historical data and literature reviews. Quantifying the impact was made by calculating the System Average Interruption Duration Index (SAIDI) and the Expected Cost (ECOST) which represented the reliability from a customer- and a socio-economic perspective. Using an optimization routine based on a Greedy algorithm an improvement of the reliability was made possible. The result of the case study showed a possible improvement of 28% on SAIDI and 41% on ECOST if optimizing the location of section points. It also indicated that loop structures containing mostly industry-, trade- and service-sectors may improve ECOST considerably by having a relocated section point. The analysis concluded that based on the considerable improvement the case study showed, a distribution system could be highly benefitted by optimizing the location of section points. The created algorithm may provide a helpful tool well representative for such a process in a cost-effective way. Applying it into a full size system was considered being possible but it would first require some additional improvements of reliability inputs and to resolve some fundamental issues like rated current in lines and geographical distances to substations.