This dissertation describes the preparation of a novel inorganic membrane for hydrogen permeation and its application in a membrane reactor for the study of the methane steam reforming reaction. The investigations include both experimental studies of the membrane permeation mechanism and theoretical modeling of mass transfer through the membrane and simulation of the membrane reactor with 1-D and 2-D models. A hydrothermally stable and hydrogen selective membrane composed of silica and alumina was successfully prepared on a macroporous alumina support by chemical vapor deposition in an inert atmosphere at high temperature. Before the deposition of the silica-alumina composite, multiple graded layers of alumina were coated on the alumina support with a mean pore size of 100 nm by the sequential application of three boehmite sols with gradually decreasing sol particle sizes of 630, 200 and 40 nm, respectively. The resulting supported composite alumina-silica membrane had high permeability for hydrogen in the order of 10-7 mol m-2 s-1 Pa-1 at 873 K with a H2 /CH4 selectivity of 940 and exhibited much higher stability to water vapor at the high temperature of 873 K. In addition, the same unusual permeance order of Heï¼ H2ï¼ Ne previously observed for the pure silica membrane was also observed for the alumina-silica membrane, indicating that the silica structure did not change much after introduction of the alumina. The permeation of hydrogen and helium through vitreous glass and silica membranes was modeled using ab initio density functional calculations. Comparison of the calculated activation energies to those reported for vitreous glass (20—40 kJ mol -1) indicated the presence of 5- and 6-membered siloxane rings, consistent with the accepted structure of glass as a disordered form of cristobalite. The experimental studies of the steam reforming of methane were examined at various temperatures (773-923 K) and pressures (1-20 atm) with a commercial Ni/MgAl2O4 catalyst in a hydrogen selective silica-alumina membrane reactor and compared with a packed bed reactor. One-dimensional and two-dimensional modeling of the membrane rector and the packed bed reactor were performed at the same conditions and their performances were compared with the values obtained in the experimental study. Improved methane conversions and hydrogen yields were obtained in the membrane reactor compared to the packed bed reactor at all temperatures and pressures. From the two modeling studies, it was also found out that the two-dimensional model performed better in the membrane reactor case especially at higher pressures. / Ph. D.

La cognition sociale a récemment connu un intérêt croissant en neuropsychologique clinique. Cet engouement s’explique notamment par le caractère transdiagnostique mais aussi invalidant des troubles. Cependant, ce construit se heurte encore à de nombreux écueils, tant conceptuels que méthodologiques. Ainsi, dans la schizophrénie, les données de la littérature internationale divergent. Nous faisons l’hypothèse que ces contradictions peuvent être sous-tendues par : 1) le manque de considération pour le caractère multidimensionnel de la cognition sociale, et 2) l’hétérogénéité interindividuelle du fonctionnement. L’objectif général de ce travail de thèse était de réaliser une étude comparée des profils de fonctionnement en cognition sociale dans la population générale et dans la schizophrénie. Pour ce faire, une première étape a été consacrée à une revue systématique des études sur la structure factorielle de la cognition sociale en neuropsychologie clinique (Article 1). Cette revue a permis de proposer un modèle bidimensionnel de la cognition sociale, où les processus de bas et de haut niveau croisent les processus affectifs et cognitifs. Une deuxième étape a consisté à fournir des éléments de validation supplémentaires au PECS-B, une batterie d’évaluation de la cognition sociale composée de sept tâches évaluant cinq dimensions (Article 2). Les résultats ont révélé des qualités psychométriques satisfaisantes en population générale (N = 131) comme dans la schizophrénie (N = 101). Enfin, la troisième étape a consisté à réaliser des analyses en clusters pour explorer l’hétérogénéité interindividuelle dans ces mêmes populations (Article 3). Trois profils différents dans l’échantillon population générale ont été mis en évidence, dont deux caractérisés par des faiblesses spécifiques. En revanche, les trois profils obtenus dans l’échantillon schizophrénie étaient caractérisés par trois niveaux de fonctionnement en cognition sociale : capacités efficientes (similaires aux témoins), moyennes et faibles. Ces deux derniers niveaux étaient également caractérisés par des difficultés d’ordre alexithymique ou neurocognitive. Dans une perspective de pratique basée sur la preuve, ces résultats ont des implications importantes tant pour l’évaluation de la cognition sociale que pour l’orientation des interventions thérapeutiques. / Social cognition has received a growing interest in clinical neuropsychology. This popularity can be explained by the transdiagnostic and negative outcome of social cognition disorders. However, this construct faces many difficulties, conceptual as well as methodological. Thus, concerning schizophrenia, data from the international literature is inconsistent. We hypothesize that these contradictions may be underpinned by: 1) a lack of consideration for the multidimensionality of social cognition, and 2) interindividual heterogeneity of functioning. The overall goal of this thesis was to explore and compare the social cognition functioning profiles in the general population with those for schizophrenia. To do this, a first step was devoted to a systematic review of studies that explored the factor structure of social cognition in clinical neuropsychology (Article 1). This review allowed the proposition of a two-dimensional model of social cognition, in which low and high-level processes cross affective and cognitive ones. A second step was to provide additional validation elements to the PECS-B, a social cognition assessment battery with seven tasks assessing five dimensions (Article 2). The results reported satisfactory psychometric qualities in the general population (N = 131) as well as in schizophrenia (N = 101). Finally, the third step was to carry out cluster analyses to explore interindividual heterogeneity in these same populations (Article 3). Three different profiles in the general population sample were highlighted, of which two were characterized by specific weaknesses. In contrast, the three profiles in the schizophrenia sample were characterized by three levels of social cognition functioning: good (similar to controls), medium and low. The last two levels were also characterized by alexithymic or neurocognitive difficulties. From an evidence-based practice perspective, these findings have important implications for both the assessment and the direction of therapeutic interventions.

Two-dimensional (2-D) models of electrical resistivity are improved by jointly inverting radiomagnetotelluric (RMT) and direct-current resistivity (DCR) data or by allowing for displacement currents in the inversion of RMT data collected on highly resistive bedrock. Uniqueness and stability of the 2-D models are assessed with a model variance and resolution analysis that allows for the non-linearity of the inverse problem. Model variance and resolution are estimated with a truncated singular value decomposition (TSVD) of the sensitivity matrix. In the computation of model errors, inverse singular values are replaced by non-linear semi-axes and the number of included eigenvectors is increased until a given error threshold is reached. Non-linear error estimates are verified with most-squares inversions. For the obtained truncation levels, model resolution matrices are computed. For RMT data, non-linear error appraisals are smaller than linearized ones. Hence, the consideration of the non-linearity in RMT data leads to reduced model errors or enhanced model resolution. The dielectric effect on RMT data is investigated with a new 2-D forward and inverse code that allows for displacement currents. As compared to the quasi-static approximation, apparent resistivities and phases of the impedance tensor elements are found to be significantly smaller and the vertical magnetic transfer function exhibits more distinct sign reversals. More reliable models of electrical resistivity are obtained from areas with highly resistive bedrock, if displacement currents are allowed for. In contrast, inversions with a quasi-static scheme introduce artefactual structures with extremely low or high resistivities. A smoothness-constrained 2-D joint inversion of RMT and DCR data is presented. The non-linear model variance and resolution analysis is applied to single and joint inverse models. For DCR data, the errors estimated by most-squares inversions are consistently larger than those estimated by the non-linear semi-axes, indicating that DCR models are poorly resolved. Certain areas of the joint inverse models are better resolved than in the single inverse models.

This thesis investigates novel algorithms for enabling the use of first-principle electrochemical models for battery monitoring and control in advanced battery management systems (BMSs). Specifically, the fast solution and state estimation of a high-fidelity spatially resolved thermal-electrochemical lithium-ion battery model commonly referred to as the pseudo two-dimensional (P2D) model are investigated. The partial-differential algebraic equations (PDAEs) constituting the model are spatially discretised using Chebyshev orthogonal collocation enabling fast and accurate simulations up to high C-rates. This implementation of the P2D model is then used in combination with an extended Kalman filter (EKF) algorithm modified for differential-algebraic equations (DAEs) to estimate the states of the model, e.g. lithium concentrations, overpotential. The state estimation algorithm is able to rapidly recover the model states from current, voltage and temperature measurements. Results show that the error on the state estimate falls below 1% in less than 200s despite a 30% error on battery initial state-of-charge (SoC) and additive measurement noise with 10mV and 0.5°C standard deviations. The parameter accuracy of such first-principle models is of utmost importance for the trustworthy estimation of internal battery electrochemical states. Therefore, the identifiability of the simpler single particle (SP) electrochemical model is investigated both in principle and in practice. Grouping parameters and partially non-dimensionalising the SP model equations in order to understand the maximum expected degrees of freedom in the problem reveals that there are only six unique parameters in the SP model. The structural identifiability is then examined by asking whether the transfer function of the linearised SP model is unique. It is found that the model is unique provided that the electrode open circuit voltage curves have a non-zero gradient, the parameters are ordered, and that the behaviour of the kinetics of each electrode is lumped together into a single parameter which is the charge transfer resistance. The practical estimation of the SP model parameters from frequency-domain experimental data obtained by electrochemical impedance spectroscopy (EIS) is then investigated and shows that estimation at a single SoC is insufficient to obtain satisfactory results and EIS data at multiple SoCs must be combined.

An integrated use of radio magnetotelluric (RMT) and controlled source tensor magnetotelluric (CSTMT) measurements, the so-called CSRMT method, has been employed in environmental and resource exploration studies. A number of case histories, including a groundwater investigation in glacial deposits, a study of fracture zones for geotechnical purposes and a mining exploration study of a copper deposit, are presented in this thesis in order to illustrate the usefulness and capability of the CSRMT method. The resolutions of the estimated models using various types of data are studied. Magnetotelluric transfer functions are used to analyze the dimensionality, the near surface resistivity distortions and the near field effects in the case of CSTMT data analysis. The near field effects in CSTMT data have also been identified by performing 2½D forward modelling. Data analysis, dimensionality tests and forward modelling show that at the lowest frequencies used the CSTMT transfer functions are generally distorted by source effects, except when the source-receiver distances are sufficient large compared with the penetration depth. Regarding CSTMT transfer functions, apparent resistivities are generally less distorted than phases. TM mode transfer functions are more affected by the sources than TE mode, while tipper vectors generally contain source signatures at all frequencies. Based on the analysis of dimensionality and source effects 2D inverse modelling of CSTMT and RMT data, as well as their combination, have been performed under the plane wave assumption. The RMT method proved to be a powerful tool for imaging the upper 50 m near-surface, but their penetration depth reduces as a conductive layer structures cover the targets at depth. The penetration depth can be increased by including the CSTMT data in the modelling if the measurements are in the far field range. The resolution of the deeper parts of the models may be improved by performing a joint inversion of TE and TM modes, if the strike direction is well-defined. Alternatively, inversion of determinant data can be performed, since the determinant data are less affected by 3D structures and source effects. However the resolution of the determinant models is somewhat degraded compared to the models inverted from combined TE and TM modes.

The diploma thesis is focused on a quantification of hydrodynamic load of overflowed bridge deck. Solution was pursued by using two–dimensional numerical simulation of open channel flow in vertical plane created in ANSYS 15.0 software (modules: Workbench, Design Modeler, Meshing, Fluent). Values of drag force, lift force, moment, drag coefficient, lift coefficient and moment coefficient is result of computation. Various types of bridge decks were tested in relation to the degree of inundation (inundation ratio) and flow velocity.The thesis provides comparison of numerical simulation with physical experimental testing and result published in accessible resources.

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