Les travaux présentés dans cette thèse peuvent être divisés en deux parties. Dans une première partie, nous avons étudié le processus de photoisomérisation dans plusieurs systèmes. Une analyse de structure électronique accompagnée d’un calcul préliminaire de dynamique semi-classique ont été appliqué à un modèle minimal du rétinal afin d’extraire les degrés de libertés les plus importants lors de l’isomérisation. Cela dans le but de construire des surfaces d’énergie potentielle diabatiques pour effectuer une étude de dynamique quantique. Une approche de type dynamique semi-classique a été appliquée à un modèle de moteur moléculaire dans le but d’étudier l’origine de l’uni-directionalité de sa rotation. Finalement, une étude de structure électronique d’un complexe de Rhénium contenant un ligand de type rétinal a été effectué pour étudier l’influence du métal sur la spectroscopie du ligand rétinal. Dans une deuxième partie nous nous sommes intéressés à l’étude des croisements intersystème dans un complexe de Rhénium. Afin de pouvoir apporter une explication à un comportement contrintuitif de ce complexe, nous avons développé un Hamiltonien modèle capable de tenir compte des couplages vibroniques interétats et spin-orbit. Cet Hamiltonien a été testé sur ce-dit système, et nous a permis, grâce à une étude de structure électronique de proposer un mécanisme de relaxation différent de celui proposé expérimentalement. / This thesis can be divided in two parts.In the first one, we have studied the photoisomerization process in several systems. An electronic structure analysis mixed with a preliminary semi-classical dynamics investigation has been applied to a minimal model of the retinal chromophore in order to select the most important degrees of freedom involved in the process. The goal of this is to build diabatic potential energy surfaces in order to conduct quantum dynamics simulations. A semi-classical approach has also been applied to a molecular motor model to study the origin of the unidirectionality of its rotary motion. Finally, an electronic structure of a rhenium complex with a retinal-like ligand has been performed to study the effect of the coordination to a metallic atom on the spectroscopy of the retinal ligand. In the second part, we have investigated the intersystem crossings in a rhenium complex. In order to bring an explanation to an experimentally observed conterintuitive behavior of this complex, we have developed a model Hamiltonian that includes both interstate vibronic coupling and spin-orbit coupling. This Hamiltonian has been tested on the said complex and, in complement to an electronic structure study, allowed us to formulate a decay mechanism different from the one proposed based on experiments.

Deux stratégies sont présentées à utiliser des effets de couplage de modes pour l’amplification de l’atténuation du son dans les conduits acoustiques. La première est de coupler le mode incident propagatif avec un mode localisé, aussi appelé résonance de Fano. Cette stratégie est présentée et validée dans un système conduit-cavité et un guide d’onde partiellement traité en paroi avec un matériau à réaction locale. La méthode “R-matrix” est introduite pour résoudre le problème de propagation d’onde. Une annulation de la transmission se produit quand un mode piégé (qui est formé par les interférences de deux modes voisins) est excité dans le système ouvert. Ce phénomène est aussi lié au croisement évité des valeurs propres et à un point exceptionnel. Dans la seconde stratégie, un réseau d’inclusions rigides périodiques est intégré dans une couche poreuse pour améliorer l’atténuation du son à basse fréquence. Le couplage de modes est du à la présence de ces inclusions. Le théorème de Floquet-Bloch est proposé pour analyser l’atténuation du son dans un guide d’onde périodique en 2D. Un croisement de l’atténuation de deux ondes de Bloch est observé. Ce phénomène est utilisé pour expliquer le pic de pertes en transmission observé expérimentalement et numériquement dans un guide 3D partiellement traitée par un matériau poreux avec des inclusions périodiques. Enfin, le comportement acoustique d’un liner purement réactif dans un conduit rectangulaire avec et sans écoulement est étudié. Dans une certaine gamme de fréquence, aucune onde ne peut se propager à contre sens de l’écoulement. Par analyse des différent modes à l’aide de la relation de dispersion, il est démontré que le son peut être ralenti et même arrêté. / Two strategies are presented to use the mode coupling effects to enhance sound attenuation in acoustic ducts. The strategy is to couple the incoming propagative mode with the localized mode, which is also called Fano resonance. This strategy is presented and validated in a duct-cavity system and a waveguide partially lined with a locally reacting material. The R-matrix method is introduced to solve the propagation problems. A zero in the transmission is present, due to the excitation of a trapped mode which is formed by the interferences of two neighboured modes. It is also linked to the avoided crossing of the eigenvalues and exceptional point. In the second strategy, a set of periodic rigid inclusions are embedded in a porous lining to enhance sound attenuation at low frequencies. The mode coupling is due to the presence of the embedded inclusions. Floquet - Bloch theorem is proposed to investigate the attenuation in a 2D periodic waveguide. Crossing is observed between the mode attenuations of two Bloch waves. The most important and interesting figure is that near the frequency where the crossing appears, an attenuation peak is observed. This phenomenon can be used to explain the transmission loss peak observed numerically and experimentally in a 3D waveguide partially lined by a porous material embedded with periodic inclusions. Finally, the acoustical behaviours of a purely reacting liner in a duct in absence and presence of flow are investigated. The results exhibit an unusual acoustical behaviour : for a certain range of frequencies, no wave can propagate against the flow. a negative group velocity is found, and it is demonstrated that the sound can be slowed down and even stopped.

Magister Educationis - MEd (Mathematics and Science Education) / The study catered for empirical and metaphysical dimensions of science and IKS. The study employed a quasi-experimental design as well as a qualitative research design. Two cohorts of students from a fictitiously named Culture Secondary School have been used in this study. The list of instruments for data collection were as follows: Conceptions of Fermentation (COF) questionnaire which was used to elicit learnerss pre- and post-test conceptions of fermentation with special reference to traditional beer or Umqombothi an Attitudes to Science (ATS) questionnaire which was used to find out the learners' worldviews, a Science Achievement Test (SAT) which was used to assess the learners' generalised knowledge of fermentation, a classroom observation schedule as well as a focus group interview schedule to gather additional qualitative data. All the instruments were in English with all technical and difficult terms in both English and isiXhosa (the learners’ home language). Both groups were exposed to Science/IKS-based lessons. The only difference between the two groups was that, the experimental group (E group) was exposed to a Dialogical Argumentation Teaching Model (DAIM) and the comparison group (C group) to a traditional teaching approach. The data gathered were both analyzed in terms of qualitative and quantitative descriptions. / South Africa

Um dos principais problemas em testes de hipóteses para a homogeneidade de curvas de sobrevivência ocorre quando as taxas de falha (ou funções de intensidade) não são proporcionais. Apesar do teste de Log-rank ser o teste não paramétrico mais utilizado para se comparar duas ou mais populações sujeitas a dados censurados, este teste apresentada duas restrições. Primeiro, toda a teoria assintótica envolvida com o teste de Log-rank, tem como hipótese o fato das populações envolvidas terem distribuições contínuas ou no máximo mistas. Segundo, o teste de Log-rank não apresenta bom comportamento quando as funções intensidade cruzam. O ponto inicial para análise consiste em assumir que os dados são contínuos e neste caso processos Gaussianos apropriados podem ser utilizados para testar a hipótese de homogeneidade. Aqui, citamos o teste de Renyi e Cramér-von Mises para dados contínuos (CCVM), ver Klein e Moeschberger (1997) [15]. Apesar destes testes não paramétricos apresentar bons resultados para dados contínuos, esses podem ter problemas para dados discretos ou arredondados. Neste trabalho, fazemos um estudo simulação da estatística de Cramér von-Mises (CVM) proposto por Leão e Ohashi [16], que nos permite detectar taxas de falha não proporcionais (cruzamento das taxas de falha) sujeitas a censuras arbitrárias para dados discretos ou arredondados. Propomos também, uma modificação no teste de Log-rank clássico para dados dispostos em uma tabela de contingência. Ao aplicarmos as estatísticas propostas neste trabalho para dados discretos ou arredondados, o teste desenvolvido apresenta uma função poder melhor do que os testes usuais / One of the main problems in hypothesis testing for homogeneity of survival curves occurs when the failure rate (or intensity functions) are nonproportional. Although the Log-rank test is a nonparametric test most commonly used to compare two or more populations subject to censored data, this test presented two constraints. First, all the asymptotic theory involved with the Log-rank test, is the hypothesis that individuals and populations involved have continuous distributions or at best mixed. Second, the log-rank test does not show well when the intensity functions intersect. The starting point for the analysis is to assume that the data is continuous and in this case suitable Gaussian processes may be used to test the assumption of homogeneity. Here, we cite the Renyi test and Cramér-von Mises for continuous data (CCVM), and Moeschberger see Klein (1997) [15]. Despite these non-parametric tests show good results for continuous data, these may have trouble discrete data or rounded. In this work, we perform a simulation study of statistic Cramér-von Mises (CVM) proposed by Leão and Ohashi [16], which allows us to detect failure rates are nonproportional (crossing of failure rates) subject to censure for arbitrary data discrete or rounded. We also propose a modification of the test log-rank classic data arranged in a contingency table. By applying the statistics proposed in this paper for discrete or rounded data, developed the test shows a power function better than the usual testing

De nos jours, la simulation des écoulements diphasiques a de plus en plus d’importance dans les chambres de combustion aéronautiques en tant qu’un des éléments requis pour analyser et maîtriser le processus complet de combustion, afin d’améliorer la performance du moteur et de mieux prédire les émissions polluantes. Dans les applications industrielles, la modélisation du combustible liquide trouvé en aval de l’injecteur sous forme de brouillard de gouttes polydisperse, appelé spray, est de préférence faite à l’aide de méthodes Eulériennes. Ce choix s’explique par les avantages qu’offrent ces méthodes par rapport aux méthodes Lagrangiennes, notamment la convergence statistique intrinsèque, le couplage aisé avec la phase gazeuse ainsi que l’efficacité pour le calcul haute performance. Dans la présente thèse, on utilise une approche Eulérienne basée sur une fermeture au niveau cinétique de type distribution Gaussienne Anisotrope (AG). L’AG résout des moments de vitesse jusqu’au deuxième ordre et permet de capter les croisements des trajectoires (PTC) à petite échelle de manière statistique. Le système d’équations obtenu est hyperbolique, le problème est bien-posé et satisfait les conditions de réalisabilité. L’AG est comparé au modèle monocinétique (MK) d’ordre 1 en vitesse. Il est approprié pour la description des particules faiblement inertielles. Il mène à un système faiblement hyperbolique qui peut générer des singularités. Plusieurs schémas numériques, utilisés pour résoudre les systèmes hyperboliques et faible- ment hyperboliques, sont évalués. Ces schémas sont classifiés selon leur capacité à traiter les singularités naturellement présentes dans les modèles Eulériens, sans perdre l’ordre global de la méthode ni rompre les conditions de réalisabilité. L’AG est testé sur un champ turbulent 3D chargé de particules dans des simulations numériques directes. Le code ASPHODELE est utilisé pour la phase gazeuse et l’AG est implémenté dans le code MUSES3D pour le spray. Les résultats sont comparés aux de simulations Lagrangiennes de référence et aux modèle MK. L’AG est validé pour des gouttes modérément inertielles à travers des résultats qualitatifs et quantitatifs. Il s’avère prometteur pour les applications complexes comprenant des PTC à petite échelle. Finalement, l’AG est étendu à la simulation aux grandes échelles nécessaire dans les cas réels turbulents dans le domaine industriel en se basant sur un filtrage au niveau cinétique. Cette stratégie aide à garantir les conditions de réalisabilités. Des résultats préliminaires sont évalués en 2D pour tester la sensibilité des résultats LES sur les paramètres des modèles de fermetures de sous mailles. / In aeronautical combustion chambers, the ability to simulate two-phase flows gains increasing importance nowadays since it is one of the elements needed for the full understanding and prediction of the combustion process. This matter is motivated by the objective of improving the engine performance and better predicting the pollutant emissions. On the industrial scale, the description of the fuel spray found downstream of the injector is preferably done through Eulerian methods. This is due to the intrinsic statistical convergence of these methods, their natural coupling to the gas phase and their efficiency in terms of High Performance Computing compared to Lagrangian methods. In this thesis, the use of Kinetic-Based Moment Method with an Anisotropic Gaussian (AG) closure is investigated. By solving all velocity moments up to second order, this model reproduces statistically the main features of small scale Particles Trajectories Crossing (PTC). The resulting hyperbolic system of equations is mathematically well-posed and satisfies the realizability properties. This model is compared to the first order model in the KBMM hierarchy, the monokinetic model MK which is suitable of low inertia particles. The latter leads to a weakly hyperbolic system that can generate δ-shocks. Several schemes are compared for the resolution of the hyperbolic and weakly hyperbolic system of equations. These methods are assessed based on their ability to handle the naturally en- countered singularities due to the moment closures, especially without globally degenerating to lower order or violating the realizability constraints. The AG is evaluated for the Direct Numerical Simulation of 3D turbulent particle-laden flows by using ASPHODELE solver for the gas phase, and MUSES3D solver for the Eulerian spray in which the new model is implemented. The results are compared to the reference Lagrangian simulation as well as the MK results. Through the qualitative and quantitative results, the AG is found to be a predictive method for the description of moderately inertial particles and is a good candidate for complex simulations in realistic configurations where small scale PTC occurs. Finally, within the framework of industrial turbulence simulations a fully kinetic Large Eddy Simulation formalism is derived based on the AG model. This strategy of directly applying the filter on the kinetic level is helpful to devise realizability conditions. Preliminary results for the AG-LES model are evaluated in 2D, in order to investigate the sensitivity of the LES result on the subgrid closures.

No description available.

En zonas con alto flujo peatonal y vehicular se presentan mayores congestiones e incidentes que afectan principalmente a los peatones y esto ocurre debido al reducido tiempo de cruce peatonal, consideraciones de diseño deficientes y el inadecuado comportamiento de los usuarios viales. Por ello, es necesario realizar el estudio y la aplicación de medidas que contribuyan a salvaguardar la seguridad de los peatones en estas áreas. Actualmente, en la intersección de las avenidas Abancay con Nicolas de Piérola, se prioriza el paso vehicular, a pesar de la alta demanda peatonal y la alta tasa de accidentes. La presente investigación tiene como objetivo reducir la cantidad de conflictos peatón-vehículo por medio de la aplicación de un crucero peatonal diagonal en esta intersección. Para ello, se construye un modelo de microsimulación en el programa VISSIM que represente el comportamiento de los usuarios y permita el análisis de la propuesta. La metodología se desarrolla en tres partes. Primero, se describe y caracteriza la intersección por medio de las visitas de campo y videos recopilados por dron. Posteriormente, los datos obtenidos se introducen al programa, el modelo resultante es calibrado y validado empleando 5 parámetros de fuerza social. Luego, se realizan modificaciones para incluir el crucero peatonal diagonal con la fase semafórica exclusiva generada en VISTRO. Finalmente, se plantea el diseño de la intersección con crucero peatonal diagonal. Como resultado, se comprueba la reducción de conflictos peatón-vehículo en un 74% y el incremento de la seguridad vial con un enfoque en los peatones. / In areas with high vehicular and pedestrian flow there are greater congestion and incidents that mainly affect pedestrians, this occurs due to many factors such as reduced crossing time, insufficient design considerations and inadequate user behavior. That is why it is necessary to study countermeasures that help safeguard pedestrians in these areas. Currently, at the intersection between Abancay and Nicolas de Pierola Avenues, the vehicular crossing is prioritized despite of the high-density pedestrian traffic and the high rates of accidents. This investigation aims to reduce the number of pedestrian-vehicle conflicts by implementing a scramble crossing at the intersection. Therefore, a microsimulation model is generate using VISSIM Software that replicate the road user behavior and allows analysis of the applied proposal. The methodology used includes three main parts. First, the intersection is described and characterized by site visits and drone videos. Second, the collected data is entered into a model that represents the current situation, for which it is calibrated and validated using 5 parameters of the social force model. Then, on current situation model, a design is made with the crosswalk proposed. An exclusive pedestrian phase is included adapting the traffic signal optimization generated by VISTRO Software. Finally, an intersection design with an appropriate pedestrian interval is presented to help to increase the road safety and it is verified with a checklist. As a result, this verifies the reduction of road incidents caused mainly by the pedestrian-vehicle conflict by 74% and focuses on improvement of road safety for pedestrians. / Tesis

The subject of the master’s thesis is to design a reconstruction of the Letovice railway station for access for persons with reduced mobility and orientation. The thesis deals with adjustment to the railway superstructure, substructure and drainage system of the station. Part of the thesis is explore the possibility of building a new railway stop.

The aim of this diploma thesis is the elaboration of a technical study of Gorkého Street in Brno - Veveří. In the diploma thesis, three variants of situations will be elaborated, which will focus on several different criteria. Variant 1st. focuses primarily on cyclists, a dedicated bike lane and a parking space with sloping and longitudinal layouts. In variant 2nd. is the effort to preserve the existing width arrangement, the original street greenery is preserved. The parking spaces are perpendicular and cycling is covered by a pictogram. Variant 3rd. is primarily concerned with the number of parking spaces. Variant 2nd. was selected for detailed development. The street will be completely reconstructed due to the construction of sewerage and water supply. All construction modifications are designed according to valid standards and regulations.

The subject of this diploma thesis is the design of a pre-station area near the railway station Uherský Ostroh on track 340: Brno - Veselí nad Moravou and its connection to existing roads. The work alternatively addresses the method of connecting the area to the road I/55 in the build-up area of the town, the arrangement of parking and bus stops. Part of the design is also the connection of the area for the needs of pedestrians and suggests places for parking bicycles.