A l'échelle de plusieurs dizaines de millions d'années, un système de subduction implique de grandes déformations de la plaque plongeante assimilée un solide viscoélastique, et du manteau supérieur assimilé à un fluide newtonien. L'objectif de ce travail est de développer une stratégie de couplage solide-fluide appliquée à l'étude de l'interaction lithosphère-asthénosphère. Cette stratégie est basée sur l'utilisation de maillages non-conformes aux interfaces et d'une méthode de domaines fictifs (MDF) pour la résolution du problème fluide. Pour l'efficience des modèles 3D, nous employons une formulation simplifiée de la méthode de domaines fictifs par multiplicateurs de Lagrange. La MDF développée est validée par des comparaisons avec des solutions analytiques qui montrent que la méthode est d'ordre 1. La stratégie de couplage est également validée par la comparaison avec d'autres méthodes de couplage solide-fluide. Une première étude est ensuite menée pour analyser l'influence de certains paramètres rhéologiques et cinématiques sur la dynamique d'une subduction contrôlée par les vitesses des plaques. Cette étude, en 2D, concerne plus spécifiquement le mécanisme de plissement périodique du slab lorsque celui-ci est ancré à 660 km de profondeur. Ce mécanisme induit des variations de pendage du slab générant des variations de l'état de contrainte de la plaque chevauchante. Un intérêt particulier est porté sur l'influence de la viscosité du manteau sur les plissements. Dans ce cadre, nous réalisons une application à la subduction andine. / Over the time scale of tens of millions of years, a subduction system involves large deformations of tectonics plates, as one plate sinks into the Earth's mantle. The aim of this work was to develop a soli-fluid coupling method applied to the lithosphere-asthenosphere interaction in the context of subduction zones. Plates were assumed to behave as viscoelastic bodies, while the upper mantle was assimilated to a newtonian fluid. The method developped here is based on the use of non-matching interface meshes and a fictitious domain method (FDM) for the fluid problem. To optimize the computational efficiency of 3D model, we used a simplified version of the Lagrange multipliers fictitious domain method. The developped FDM has been benchmarked with analytical solutions and we showed that this FDM is a first-order method. The coupling method has also been compared to other fluid-solid coupling methods using matching interfaces meshes. A first two-dimensional study was performed in order to evaluate the influence of some rheological and kinematic parameters on the dynamics of a subduction controlled by the velocity of the plates. This study aimed at investigating cyclic slab folding over a rigid 660 km depth transition zone. This folding mechanism induces variations in slab dip that generate variations in the stress state of the overriding plate. We focussed on the influence of the upper mantle viscosity on slab folding. We also applied this model to the Andean subduction zone. Several studies have determined a cyclic variation of the South-American tectonic regime (period of 30-40~Myrs) which may have been related to the slab dip evolution.

The rise in the world population can be correlated with an increase in energy need. Fossil fuels are not going to able to cover this need in energy because not only are they limited, they also have a negative effect on the environment. A reason the more to switch renewable energy. One of the most popular renewable energy source is solar energy. The organic solar cell could be a low-cost, light-weight and flexible option for photovoltaics. This thesis will discuss the morphology of the active layer of an organic solar cell. The polymer poly(9,9-dioctylfluorenyl-2,7-diyl) and the fullerene derivate [6,6]-phenyl C61-butyric acid methyl ester were used as model components for the active layer. These two components were processed in different solvents, different ratios, different total concentrations and were either dip- or spin-coated on glass substrates. These samples were analyzed with atomic force microscopy, steady state and time resolved fluorescence and UV/Vis spectroscopy. The analysis show that the morphology of the films processed in chloroform and tetrahydrofuran would react very similar in α-phase and β-phase by dip- and spin-coated samples. Xylene would react the opposite as tetrahydrofuran and chloroform while ethylbenzene would react little with different samples. / De stijging in wereldpopulatie kan gelinkt worden met een stijging in energieverbruik. Het is niet aan te raden om fossiele brandstoffen te gebruiken voor deze energiestijging want niet alleen zijn ze beperkt aanwezig op aarde ook zijn ze niet goed voor het milieu. Een reden te meer om naar duurzame energie over te schakelen. Één van de meeste populaire energiebronnen is zonne-energie. Hierbij zou de organische zonnecel een goedkope, lichte en flexibele optie zijn. Deze thesis zal de morfologie van de actieve laag van een zonnecel bespreken. Het polymeer poly(9,9-dioctylfluorenyl-2,7-diyl) en het fullereen derivaat [6,6]-fenyl C61-butylzuur waren de twee model componenten voor de actieve laag. Deze twee componenten werden in verschillende oplosmiddelen, verschillende verhoudingen en verschillende totaal concentraties bereidt en werden vervolgens gedipcoated of gespincoated op glazen substraten. De stalen werden vervolgens geanalyseerd door atomic force microscopy, steady state en time resolved fluorescence en UV/Vis spectroscopy. De analyse toont dat de morfologie van de films bereidt in chloroform en tetrahydrofuraan gelijkaardig reageren in α- fase en β-fase bij gedipt- en gespincoaten stalen. Terwijl xyleen net omgekeerd reageert als chloroform en tetrahydrofuraan. Bij ethylbenzeen zou de fases maar heel weinig veranderen bij de verschillende stalen.

This thesis focuses on economic situation assessment of a company active in the field of manufacturing industry. The assessment is done using elementary methods of financial analysis. Based on the results, measures are suggested to improve the financial situation of the company. An analysis of general and field-specific surrounding of the assessed organization is also included in the thesis.

The work deals with the deposition of layers for electrochromic device with different methods. Transparent electrically conductive layer of SnO2 was deposited by pyrolytic decomposition of peroxostannate solution. Hydrogen peroxide in starting solution contributes to the oxidation process of growth layers and to increase the electrical conductivity. Active electrochromic layer of WO3 was electrolytic deposited from the peroxotungstic acid solution. Optimal deposition time and the optimal annealing temperature of deposited layers were found. Passive electrochromic layer of V2O5 was deposited using dip-coating method from peroxovanadate solution. A contribution of solution diluted with distilled water was investigated. Found results were used to construct complete electrochromic device with polymer gel electrolyte.

Basic facial emotion recognition is suggested to be negatively affected by puberty onset reflected in a “pubertal dip” in performance compared to pre- or post-puberty. However, findings remain inconclusive. Further, research points to an own-age bias, i.e., a superior emotion recognition for peer faces. We explored adolescents’ ability to recognize specific emotions. Ninety-five children and adolescents, aged 8–17 years, judged whether the emotions displayed by adolescent or adult faces were angry, sad, neutral, or happy. We assessed participants a priori by pubertal status while controlling for age. Results indicated no “pubertal dip”, but decreasing reaction times across adolescence. No own-age bias was found. Taken together, basic facial emotion recognition does not seem to be disrupted during puberty as compared to pre- and post-puberty.

No description available.

Alloy 617 displays a ductility dip during straining at exactly 1000˚C, leading to brittle fracture. A sudden decrease in ductility appearing during Gleeble hot ductility tests of Ni-based superalloys is a well-known phenomenon, while its cause is unknown. Many mechanisms have been established as possible contributors to the issue, and in later years not one, but the simultaneous presence of several of these mechanisms were confirmed as the cause. The ductility dip leads to solid state cracking and a specific solid state cracking phenomenon known as ductility dip cracking is specifically common in Ni-based superalloys. Ductility dip cracking is identified by intergranular cracks and the occurrence of specific precipitates, among other things. This work investigates the possibility that the decreased ductility is due to ductility dip cracking. Furthermore, other possible explanations are investigated. Visual examination was conducted through LOM, SEM and chemical analysis using EDS technique. Combined with thermodynamic calculations, the existence of Cr-rich M23C6 carbides, Ti(N,C) and Mo-rich particles, most likely M3B2, were confirmed. Further, it is established that the ductility dip is related to the lack of dynamic recrystallization at 1000˚C. It is not confirmed that the ductility dip in alloy 617 is due to ductility dip cracking. / Nickelbaslegeringen 617 uppvisar en minskning i duktilitet under Gleeble-dragprovning vid exakt 1000˚C vilket leder till sprött brott. En plötslig sänkning av duktiliteten vid varmdragning av Ni-baserade superlegeringar är ett välkänt fenomen, dock är orsaken inte fastställd. Många mekanismer har bekräftats som bidrag till problemet och under de senaste åren har den simultana närvaron av fler av dessa mekanismer bekräftats som orsaken. Sänkningen i duktilitet leder till sprickbildning i fast fas och en specifik typ av sprickbildning känd som ”ductility dip cracking” är speciellt förekommande i Ni-bas legeringar. Denna identifieras bland annat genom intergranulära sprickor och närvaron av specifika utskiljningar. Detta arbete undersöker möjligheten att duktilitetssänkningen beror på  ”ductility dip cracking”. Dessutom undersöks fler tänkbara förklaringar. Visuell granskning genomfördes via LOM och SEM och analys av sammansättningar via EDS-analys. I kombination med termodynamiska simuleringar blev förekomsten av Cr-rika M23C6 karbider, Ti(N,C) och Mo-rika partiklar, troligtvis M3B2, bekräftad. Fortsatt är det bekräftat att duktilitetssänkningen är relaterat till avsaknaden av rekristallisation vid 1000˚C. Det är inte bekräftat i detta arbete att duktilitetssänkningen i legering 617 beror av ”ductility dip cracking”.

This project deals with voltage source converters with energy storage capability. The main objective is to study the possible benefits of energy storage to a power system with a VSC as the interface between them. First of all, a converter control system is proposed for a two level VSC. In the conventional converter control, the control system usually takes the voltage measured at the point where the converter is connected and calculates the reference voltage for the converter; with a modulation system the converter then produces the required 'average voltage'. In this project, a novel flux modulation scheme, combined with the deadbeat current control strategy, is proposed. The current controller is capable of controlling both positive and negative sequence current components. With flux modulation, the control system measures the bus flux and commands the converter to generate the required flux. Based on the proposed control strategies, several application studies have been carried out. The first application study investigates the effect of energy storage on the power quality at the point of common coupling when a system is subject to load disturbances. The voltage at PCC in a weak network is very sensitive to load changes. A sudden change in active load will cause both a phase jump and a magnitude fluctuation in the bus voltage, whereas reactive load changes mainly affect the voltage magnitude. With the addition of energy storage to a StatCom, it is possible to compensate for the active power change as well as providing reactive power support. In this thesis, some effective active power compensation schemes are proposed. Simulations and experiments have been performed to verify the compensation schemes. The results show that a StatCom with energy storage can significantly reduce phase jumps and magnitude deviations of the bus voltage. pact of the energy storage on the performance of weak systems under fault conditions has been investigated. The investigation was done by studying an example system. The system model was established based on a real system, in which some induction motors driving pumps along a pipeline are fed from a radial transmission line. Studies show that for a weak system with induction motor loads, a StatCom with certain energy storage capacity will effectively improve the system recovery after faults. Although this incurs extra cost for the increasing dc voltage rating and size of the dc side capacitor, the overall rating of the converter can be reduced by utilization of the proposed active power compensation scheme. The last case study investigates the possible use of a StatCom with energy storage to improve the power quality at the point of common coupling where a cyclic load is connected. Studies show that by providing both fast reactive and fast active power support to the network, not only the voltage magnitude can be well controlled, but also the voltage phase jump can be reduced significantly. / QC 20101124

No description available.

Recently, Zn-XAl-YMg coatings have emerged as lighter-weight substitutes for traditional Zn-based coatings for the corrosion protection of steels; however, little is currently known concerning the interactions between the oxides present on advanced high strength steel (AHSS) surfaces and the Zn-Al-Mg bath. In the current contri- bution, the selective oxidation and reactive wetting of a series of C-Mn AHSS were determined with the objective of providing a quantitative description of this pro- cess. The process atmosphere pO2 was varied using dew points of −50◦C, −30◦C and −5◦C. The surface oxide chemistry and morphology were analysed by means of SEM and XPS techniques. Reactive wetting of the selectively oxidized surfaces using a Zn-1.6 wt.% Al-1.6 wt.% Mg bath was monitored as a function of annealing time at 60 s, 100 s and 140 s at 800◦C. The resulting bare spot defects in the Zn-1.6 wt.% Al-1.6 wt.% Mg coating were assessed by means of SAM-AES and FIB, while coating adhesion was analysed by 180◦ bend tests. Annealing the steel substrates resulted in the formation of surface MnO, which varied based on pO2 and Mn alloy content, and that this MnO greatly reduced the wettability of the steel by the Zn-1.6 wt.% Al- 1.6 wt.% Mg bath, resulting in bare spot defects. It was determined that the reactive wetting of the steel substrate was dependant on the oxide morphology and oxidation mode, which was a function of both alloying content of Mn in the steel and annealing pO2 process atmosphere (dew point). Finally, it was concluded that the bare spot area percentage on the coated panels was statistically invariant for annealing times of between 60 s and 140 s at 800◦C. / Thesis / Master of Applied Science (MASc) / Metallic coatings are applied to steels that are not naturally corrosion resistant. The aim of this research was to determine how well a coating containing zinc, aluminum and magnesium adhered to high strength automotive steel. It was deter- mined that manganese oxides formed on the steel during heating prior to applying the metallic coating. The manganese oxides prevented good adhesion between the steel and the coating, resulting in bare spot defects in the coating. The bare spot defects are undesirable as they leave the steel exposed and therefore susceptible to corrosion and are unsightly when painted.