Le (Ga,Mn)As est un matériau de choix pour l'électronique de spin, étant à la fois semiconducteur et ferromagnétique, à la suite de l'interaction d'échange entre les spins des atomes de manganèse (3d5-4s2), et ceux des trous qu'ils apportent. Sa température de Curie (Tc) se situe typiquement entre 50 et 150 K.<br />Afin de découpler les dopages magnétique ([Mn]) et électrique (p), une technique de passivation par hydrogène a été développée, pour former des complexes (Mn,H) électriquement neutres. Ses effets magnétiques (apparition d'une phase paramagnétique), électriques (diminution de p) et structuraux sur la couche ont tout d'abord été étudiés. <br />Puis, des échantillons de dopage croissant ont été fabriqués grâce à ce procédé, pour des couches en tension ou en compression. Un bon accord avec les prévisions de la théorie de champ moyen a été obtenu pour l'évolution de leur anisotropie magnétique, et de leurs Tc en fonction de la contrainte épitaxiale, et de la densité de porteurs.<br />Une dernière étude s'est penchée sur les domaines magnétiques et les mécanismes de renversement d'aimantation de couches continues, puis de microstructures monodomaines aimantées perpendiculairement au plan. Un procédé de passivation locale par hydrogénation a été développé pour structurer magnétiquement des couches de (Ga,Mn)As (taille minimale des motifs ~ 200 nm). Il a entre autres permis d'abaisser fortement les champs de retournement d'aimantation de réseaux de plots microniques, par rapport à ceux obtenus dans des structures fabriquées par gravure. Enfin, des résultats préliminaires de déplacement de parois de domaines par un champ magnétique ou un courant polarisé ont été obtenus dans des pistes structurées par hydrogénation.

Die elektrische Dehnungsmesstechnik auf der Grundlage separater Dehnungsmessstreifen (DMS) stellt heute eine der wesentlichsten Methoden zur experimentellen Beanspruchungs- analyse dar. Präzise Messungen außerhalb der Kalibrierbedingungen, insbesondere bei großen Deformationen oder hohen Querdehnungsanteilen, erfordern die Berücksichtigung nicht- linearer Zusammenhänge zwischen den zu bestimmenden Komponenten der Bauteildehnung und der Widerstandsänderung des Messgitters. Die Theorie dieser Zusammenhänge wird in zwei unterschiedlichen Formulierungen dargestellt. In der ersten Formulierung werden die für den Messgitterwerkstoff geltenden Leitfähigkeiten durch einem dreidimensionalen Ansatz mit den Dehnungskomponenten im Leiter verknüpft. Die Bestimmung der definierten Leitfähigkeitsparameter erfolgt exemplarisch für eine DMS-Konstantanfolie. In Form von Übertragungsfaktoren wird berücksichtigt, dass die Querdehnungskomponente der Bauteildehnung nicht vollständig auf die Stege und Umlenkstellen des Messgitters übertragen wird. Die zweite Formulierung basiert auf den vom DMS-Hersteller angegebenen Empfindlichkeiten präparierter Dehnungsmessstreifen in Längs- und Querrichtung. Die Genauigkeit der abgeleiteten Widerstands-Dehnungsbeziehungen wird durch zwei unter- schiedliche Versuche, bei denen die DMS-Messstellen längs bzw. quer zum einachsigen Spannungsfeld orientiert sind, überprüft. Die maximalen Dehnungen betragen dabei 5 bzw. 8 %.

IH-35 is a major north-south interstate highway across the State of Texas. It is an important business corridor, conveniently connecting four large Texas cities, Austin, Dallas, Fort Worth, and San Antonio, as well as facilitating trade between Mexico and the United States. During construction of the SH-71/IH-35 Interchange, the Austin District of the Texas Department of Transportation (TxDOT) has had to close the main lanes of IH-35 and re-route traffic. Three main lane closures happened during three weekends in 2011. During those closures, a parallel route, the SH-130 toll road, was made free to travelers. TxDOT provided both pre-trip and en-route information about the closure. They used radio, TV, portable message sign (PMS), and dynamic message signs (DMS) to inform commuters about the closure. To inform travelers passing through Austin about the closure and the existing alternative (SH-130 was toll free), they even collaborated with Dallas and San Antonio TxDOT district personnel. However, usage of SH130 was less than anticipated, and there was significant traffic queuing on IH-35. In this study, we tried to document the quantity of traffic that used the alternative path during the IH-35 closure and explore options for relieving delays on IH-35 during future closures. / text

Field asymmetric waveform ion mobility spectrometry (FAIMS) is a gas phase atmospheric pressure separation technique that exploits the difference in the mobility of ions in alternating low and high electric fields as they are carried between two electrodes. In this thesis, a miniaturised FAIMS separation step has been applied to increase selectivity, enhance sensitivity and improve the quality of mass spectral data for rapid, high-throughput protein and peptide analysis. In Chapter 2, charge state separations were used to generate pseudo-peptide mass fingerprint data by FAIMS-MS, permitting confident protein identification using ESI sample introduction as an alternative to MALDI-TOF-MS methods. In addition, pre-cursor ions were targeted prior to MS/MS analysis. Chapter 3 describes the analysis of intact proteins by miniaturised FAIMS-MS. Multiple charge states of intact proteins were separated on the basis of differences in differential mobility. Higher charge states were found to be transmitted at similar CVs suggesting that the miniaturised FAIMS device was separating ions on the basis of 3D structure. In addition, multiple species could be observed at the same m/z suggesting the presence of different protein conformers. In Chapter 4, miniaturised FAIMS was used to select ions on the basis of differential mobility prior to in-source collision-induced dissociation CID, LC and ToF-MS analysis for qualitative and quantitative analysis of peptides mixtures. This was applied to the analysis of co-eluting model peptides and tryptic peptides derived from human plasma proteins, allowing precursor ion selection and CID to yield product ion data suitable for peptide identification via database searching.

Functional magnetic resonance imaging (fMRI) is a relatively new tool that has been used to examine patterns of neural activation within those with traumatic brain injuries (TBI). A review of relevant literature is presented, including alterations in activity within the frontal and parietal regions that are thought to be compensatory in nature. In addition, possible explanations for discrepancies within this research are discussed. The current study expands upon previous work by incorporating a delayed-match-to-sample (DMS) task within an event-related paradigm and neuropsychological testing to compare 12 individuals with a history of TBI to 12 control participants with orthopedic injuries (OI). Participants in the TBI group were high functioning and in the chronic stage of recovery. Neuropsychological testing revealed statistically significant group differences in measures of working memory, processing speed, memory, and executive functioning. However, groups were comparable in accuracy on the DMS task. Percent signal changes in fMRI data revealed statistically significantly increased activation within the right dorsolateral prefrontal cortex (BA 46) for the TBI group compared to controls. Additional alterations in activation were found between groups within the inferior temporal (BA 37) and parietal (BA 7) regions. Regression analyses showed no relationship between neuropsychological testing and percent signal change within BA 46, but predictive relationships between testing and BA 37 and BA 7. Logistic regression analyses suggest that fMRI data did not add any incremental predictive value beyond neuropsychological testing alone when attempting to predict group (TBI vs. OI) membership.

Ce travail se situe dans un cadre d'étude de matériaux et de structures présentant les propriétés physiques recherchées pour de futures applications en électronique de spins. Les semi-conducteurs magnétiques dilués sont de bons candidats à l'utilisation simultanée de la charge et du spin des électrons ou des trous. Nous exploitons la possibilité d'induire une polarisation de spins totale, d'un gaz de trous 2D dans un puits quantique de (Cd,Mn)Te dopé par modulation ; et ceci à faible champ magnétique. L'accent est mis sur l'identification des niveaux d'énergie mis en jeu lors de la photoluminescence, ainsi que les énergies caractéristiques du système (énergie de liaison du trion positif dans l'état singulet, excitations et polarisation du gaz 2D), en fonction du champ magnétique et de la densité de trous. Nous démontrons aussi que l'aimantation d'un puits quantique de (Cd,Mn)Te, inséré dans une structure de diode pin, peut être contrôlée par l'application d'une tension électrique.

The ocean emission and subsequent oxidation of dimethylsulfide (DMS) provides a source of sulfate in the atmosphere, potentially affecting the amount of solar radiation reaching the Earth's surface through both direct and indirect radiative effects of sulfate aerosols. DMS in the ocean can be quite variable with season and location, which in turn leads to high spatial and temporal variability of ocean DMS emissions. This study tested currently available observational and empirically-based climatologies of DMS concentration in the surface ocean. The exploration of the existing parameterizations mainly reveals the limitations of estimating DMS with an empirical model based on variables such as chlorophyll and mixed layer depth. The different algorithms show significant differences in spatial pattern, and none correlate strongly with observations. There is considerable uncertainty both in terms of the spatiotemporal distribution in DMS concentration and flux, as well as in the global total DMS flux. The present research investigates the influence of DMS on sulfate aerosols and radiative fluxes given different DMS climatologies in the fourth generation of the Canadian Global Atmospheric Climate Model (CanAM4.1). In general, the response in the radiative flux seems to follow the variation in the global mean flux of DMS linearly. Differences in the spatial and temporal structure of oceanic DMS have only a secondary effect on the radiative changes. The overall response of the atmosphere to the presence or absence of structure of DMS in space and time is distinctly smaller compared to the possible uncertainty of this response associated with the magnitude of the annually averaged global flux. / Graduate / 0425 / 0725 / 0416 / jetesdal@uvic.ca

Submitted by Cláudia Bueno (claudiamoura18@gmail.com) on 2015-10-15T20:22:58Z No. of bitstreams: 2 Dissertação - Hermínia Veridiana dos Santos Pessoni e Silva - 2014.pdf: 14354082 bytes, checksum: d89e39503d04982864d158786be9e59b (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Rejected by Luciana Ferreira (lucgeral@gmail.com), reason: A primeira letra das palavras-chaves são em maiúscula. Vc colocou: ferromagnetism, reação de combustão, BMP, spintrônica, combustion reaction spintonics on 2015-10-16T11:10:10Z (GMT) / Submitted by Cláudia Bueno (claudiamoura18@gmail.com) on 2015-10-16T16:35:28Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação - Hermínia Veridiana dos Santos Pessoni e Silva - 2014.pdf: 14354082 bytes, checksum: d89e39503d04982864d158786be9e59b (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-10-19T14:33:30Z (GMT) No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação - Hermínia Veridiana dos Santos Pessoni e Silva - 2014.pdf: 14354082 bytes, checksum: d89e39503d04982864d158786be9e59b (MD5) / Made available in DSpace on 2015-10-19T14:33:30Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação - Hermínia Veridiana dos Santos Pessoni e Silva - 2014.pdf: 14354082 bytes, checksum: d89e39503d04982864d158786be9e59b (MD5) Previous issue date: 2014-05-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This work has as a general proposition the production of a DMS based on ZnO semiconductor and Co transition metal, as well as the study of the origin of ferromagnetism in these materials using the models of magnetic interaction in the literature. The combustion reaction was chosen as a synthesis route for the production of samples Zn1 - x Co x O with molar concentrations of x= 0,00, 0,005, 0,01, 0,03, 0,05, 0,07 and 0,09. The samples were obtained in the form of powders and chemical, structural and morphological characterization performed by EDS, DRX e MET measures. These characterizations indicated good crystallinity with the formation of the hexagonal crystalline phase wurtizita characteristic of ZnO without adding spurious phase for all molar concentrations. Powders presented nanometric dimension (~ 18 nm) with spherical particle shape and molars contractions of very similar elements of stoichiometric proposals. The optical characterizations via FTIR e UV-Vis confirmed the presence of the bond Zn - O and the replacement of Zn for Co in tetrahedral sites in ZnO crystal structure in the samples with x 0,00. By UV-Vis spectroscopy was also possible to obtain the optical bandgap values of the samples and confirm the semiconducting property, as well as calculate the dielectric constant of these materials. Magnetic characterizations performed by VSM measures (room temperature and high temperature) and Magnetometry at low temperatures indicated wide variety of magnetic systems in the studied temperature range. The x = 0,05 sample showed ferromagnetism across the temperature range of 5< Y (K) < 594. This same sample showed a value of 2,66 effective moment magnetic dipole and 2,52 for the saturation magnetization at low temperatures, that are significant results compared to several papers published. Through adjustments to the theoretical models, the ferromagnetism at low temperatures was attributed to the BMP magnetic interaction model. The room temperature ferromagnetismo was attibuted to the RKKY interaction model due to the high density of defects and free charge carriers in the samples. / Este trabalho teve como proposta geral a produção de um DMS com base no semicondutor ZnO e no metal de transição Co, bem como o estudo da origem do ferromagnetismo neste material utilizando de modelos de interação magnética existentes na literatura. A reação de combustão foi escolhida como rota de síntese para a produção das amostras de Zn1 -xCox O com concentrações molares de x= 0,00, 0, 005, 0,01, 0,03, 0,05, 0,07 e 0,09. As amostras foram obtidas na forma de pós e as caracterizações químicas, estruturais e morfológicas realizadas por meio de medidas de EDS, DRX e MET. Estas caracterizações indicaram boa cristalinidade com formação da fase cristalina hexagonal wurtizita característica do ZnO sem adição de fase espúria para todas as concentrações molares. Os pós apresentaram dimensão nanométrica (~ 18 nm) com formato esférico das partículas e contrações molares dos elementos muito próximas das propostas estequiometricamente. As caracterizações ópticas via FTIR e UV-Vis confirmaram a presença da ligação e a substituição do Zn por Co nos sítios tetraédricos da estrutura cristalina do ZnO nas amostras com x diferente 0,00. Pela espectroscopia UV-Vis também foi possível obter os valores de bandgap óptico das amostras e confirmar a propriedade de semicondutividade, bem como, calcular a constante dielétrica destes materiais. Já as caracterizações magnéticas realizadas via medidas de VSM (temperatura ambiente e a altas temperaturas) e Magnetometria à baixas temperaturas indicaram grande variedade de ordenamentos magnéticos em toda a faixa de temperatura estudada sendo ferromagnetismo identificado na faixa de temperatura de 5 < T (K) < 594 para a amostra x = 5. Essa amostra também apresentou valor de 2,66 para o momento de dipolo magnético efetivo e 2,52 para a magnetização de saturação à baixas temperaturas que são resultados expressivos em comparação à diversos trabalhos publicados. O ferromagnetismo à baixas temperaturas foi atribuído, por meio de ajustes com os modelos teóricos, ao modelo de interação magnética BMP, já o ferromagnetismo à temperatura ambiente ao modelo de interação RKKY devido à alta densidade de defeitos e portadores de cargas livres nas amostras.

This work documents the whole process of developing an information system for a small advertising agency. Its main sphere of business is the internet, hence the company is classified as a digital or interactive agency. My objectives are: analyzing business processes, assembling the functional specification and developing the core of the application and the module for a document management. I start with gathering some common parameters of DMS along with requirements for a web application framework, which is intended to use for a base of the intranet. Then I move to presenting specifics of our agency and I analyze its processes in order to capture all content and desired functionality of the developed system. Next phase is dedicated to design. First, I set the intranet in the context of global Enterprise architecture. I continue with modeling all architectural layers (conceptual, technological and implemental). The application is modular and benefits from using MVC architectural pattern. DMS module implements workflow functionality and I have used principles of Workflow Management Coalition to design that features. The last part of my work describes developed modules in more detail. My objectives were accomplished, core of the intranet is developed and currently in process of testing.

Enterprise document management has been in a long-term progress. Not long ago only files and folders were enough for enterprise document management, but nowadays most of enterprise documents are in the electronic form. The electronisation of enterprise documents has carried simplified manipulation, but it has also caused disorderliness in many cases. Systems called Document managament system (DMS) bring support for better management of electronic enterprise documents. This diploma thesis deals with the implementation of DMS into the environment of a specific company where it is designed to support effective function concerning enterprise document management.