Epstein et al.'s Theory of Overlapping Spheres of Influence focuses on the interaction and communication, or partnerships, among families, schools, and the community to bring the three closer together. The theory works in conjunction with Epstein's typology of parental involvement, which focuses on six types of involvement that are instrumental to a child's development and his/her school and educational success. These serve as the framework for the study and support the construct of parent's involvement in children's schooling. The purpose of the current study was to conduct further validation analyses of an inventory designed to measure the construct of parent involvement in their children's schooling through the investigation of measurement invariance to determine if the measurement properties of the inventory varied by race/ethnicity. The study compared the responses of 126 Hispanic parents/guardians with 116 White/non-Hispanic parents/guardians to investigate if these two groups were interpreting the items on the inventory in the same manner. The inventory was administered to a sample of parents/guardians of children in grades 3 through 5 in a local school district. Findings indicated that the measurement model was misspecified for the White/non-Hispanic group and the Hispanic group and further measurement invariance testing was not conducted. Exploratory factor analyses were conducted in order to investigate which models would best fit the data for both groups. Feedback also was obtained from parents/guardians about the clarity of the inventory, which revealed their confusion with the response scale and the wording of particular items. In addition, they supplied issues or aspects of parent involvement that they found important but missing from the inventory. Results from the psychometric analyses and qualitative feedback indicated that the inventory requires modification and further psychometric investigation. In addition, caution should be exercised for anyone who may be considering utilizing the inventory. Results of the study were interpreted in terms of contributions to the parent involvement literature, as well as recommendations for the improvement of the inventory.

As a result of growing attention in cross-cultural research, existing measurement instruments developed in one language are being translated and adapted for use in other languages and cultural contexts. The benefits of having the same instrument across cultures can only be realized if the process of translation and adaptation of the measurement instruments produces measurement operations that function similarly across national and cultural boundaries. Producing invariant measurement instruments that assess educational and psychological constructs provide a way of testing the cross-cultural generality of theories that include these constructs. The major purposes of the study were to translate and adapt the Teaching Perspectives Inventory (Pratt, 1992, 1990) from English to Bahasa Malaysia and compare the psychometric properties of the two versions. The TPI is an instrument developed by Pratt (1992) to ascertain the different conceptions that teachers in higher education have about teaching. The TPI has 45 items, which are divided into five subscales or perspectives referred to as Transmission, Apprenticeship, Developmental, Nurturing, and Social Reform. The first phase of this study translated and adapted the TPI from English into the Malay language of Malaysia or Bahasa Malaysia (BM) using multiple approaches as recommended by the International Test Commission. The approaches used to translate the TPI included forward and back translations, an expert panel review, a pilot study, and cognitive interviews. In the translation process, three initial translators, two back translators, and six expert panel members, including the researcher, came up with a pre-final version of the Malay TPI. During the translation process, two items were found to contain expressions that had no exact equivalent forms in Malay: "virtuoso performers" and "higher ideals." Overall, translating the TPI was a challenging task due to the relatively large number of items in the instrument (45) as well as the complexity and very abstract nature of the constructs. Many of the words and expressions that were brief and concise in the English version became longer and more verbose when translated in Malay. As a result, the translated TPI version appeared longer than the original version. Pilot testing with 25 native speakers of Malay who were faculty members from a number of public universities in Malaysia revealed nine items that needed modification. Cognitive interviewing with five participants from the pilot group revealed one item requiring a change by adding a borrowed word "novis" in brackets next to the Malay expressions, which refers to the original word novice. Due to the confusion with the words referring to `people' in many of the items, additional instructions were added at the beginning of the survey to ensure that the participants responded according to the original intention of the items, which focuses on learners in the faculty's specific classroom context instead of people in the society in general. Following changes to the TPI, this instrument was administered in phase two to a Malaysian sample of 561 faculty. In the second phase, the study assessed the psychometric properties of the original English version of the TPI with 605 faculty in the U. S. and the translated TPI version of the TPI with the Malaysian sample. The overall internal consistency reliability of both the English (α=.88) and the Malay TPI (α=.93) appeared to be adequate. At the subscale level, the internal consistency reliabilities of all the scales were on the lower side considering the large number of items (9) for each subscale (range = .67 to .83 for the U. S. and .59 to .81 for Malaysia). It was found that three out of the five subscales of the U. S. and Malay TPI had similar alpha reliabilities (Apprenticeship, Nurturing, Social Reform). To assess the cross-cultural factorial validity and measurement invariance of the TPI, confirmatory factor analysis (CFA) was carried out for both the original and the Malay TPI. The sample size for the U. S. group was 605 and the Malay group was 561. The fit for both the U. S. and the Malay correlated five-factor models was less than adequate with the Malay model showing a much worse fit. Correlated errors were found between 64 item pairs in the U. S. model and 389 item pairs in the Malay model. The correlations between the five perspectives in the Malay sample were much higher than those in the U. S. sample suggesting that the perspectives had limited discriminant validity. For example, the correlations between the Nurturing and Developmental perspectives and Nurturing and Social Reform perspectives were 1.0. The inadequate fit of the five-factor correlated model in the Malaysian sample and the minimally acceptable fit in the U. S. sample led to the decision to carry out analyses and compare the groups one subscale at a time. Model modifications for each subscale of both samples were carried out to improve the fit by adding one or more parameters (i.e., correlated errors) for each subscale model to obtain acceptable baseline models. The results of the invariance testing for each subscale did not support the existence of measurement invariance. Overall, the results indicate that the Malay version of the TPI is not ready for use and additional translation and adaptation work is recommended. Future efforts could incorporate improvements in the translation process in the form of recruiting a larger number of certified translators who have in-depth knowledge of teaching in higher education as well as a deep knowledge of the philosophy and purposes behind the TPI. Additional cognitive interviews before and after pretesting and pilot testing of the pre-final version are recommended. Finally, adding a large sample of bilingual educators who would complete both the Malay and English versions of the TPI would provide important psychometric data on the equivalence of the TPI items.

Les propriétés physiques d'un système homogène à l'équilibre thermodynamique sont fortement contraintes par sa dimensionnalité. Le gaz de Bose à deux dimensions est un système particulier de ce point de vue : bien que l'établissement d'un ordre à longue portée soit impossible à température non-nulle, il existe néanmoins une transition de phase vers un état superfluide à basse température. De plus, la dimensionalité réduite du système rend son équation d'état invariante par changement d'échalle pour de faibles interactions atomiques répulsives. Dans ce manuscrit de thèse, nous présentons une étude expérimentale du gaz de Bose à deux dimensions. Nous mesurons son équation d'état de deux methodes différentes, et trouvons un résultat en bon accord avec les prédictions analytiques et numériques. Ces résultats ont également permis de confirmer l'invariance d'échelle du système. De plus, l'une des méthodes ne nécessite qu'un seul paramètre ajustable pour la mesure de l'équation d'état. Nous présentons ensuite une mesure locale du caractère superfluide du gaz. À cet effet, nous avons mis en évidence l'absence de dissipation lors de la perturbation du système par un obstacle en mouvement. Enfin, nous effectuons une analyse des fluctuations du gaz de Bose 2D, qui a permis de confirmer la suppression des fluctuations de densité dans la phase superfluide, ainsi que le rôle dominant joué par les phonons dans les fluctuations de phase.

In this paper, we present a nonlinear curvelet-based sparsity-promoting formulation for three problems in seismic processing and imaging namely, seismic data regularization from data with large percentages of traces missing; seismic amplitude recovery for subsalt images obtained by reverse-time migration and primary-multiple separation, given an inaccurate multiple prediction. We argue why these nonlinear formulations are beneficial.

The Kalman Filter has many applications in control and signal processing but may also be used to reconstruct a higher resolution image from a sequence of lower resolution images (or frames). If the sequence of low resolution frames is recorded by a moving camera or sensor, where the motion can be accurately modeled, then the Kalman filter may be used to update pixels within a higher resolution frame to achieve a more detailed result. This thesis outlines current methods of implementing this algorithm on a scene of interest and introduces possible improvements for the speed and efficiency of this method by use of block operations on the low resolution frames. The effects of noise on camera motion and various blur models are examined using experimental data to illustrate the differences between the methods discussed.

Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal

Cette thèse porte sur les relations entre les processus SLE, les ensembles CLE et le champ libre Gaussien. Dans le chapitre 2, nous donnons une construction des processus SLE(k,r) à partir des boucles des CLE(k) et d'échantillons de restriction chordale. Sheffield et Werner ont prouvé que les CLE(k) peuvent être construits à partir des processus d'exploration symétriques des SLE(k,r).Nous montrons dans le chapitre 3 que la configuration des boucles construites à partir du processus d'exploration asymétrique des SLE(k,k-6) donne la même loi CLE(k). Le processus SLE(4) peut être considéré comme les lignes de niveau du champ libre Gaussien et l'ensemble CLE(4) correspond à la collection des lignes de niveau de ce champ libre Gaussien. Dans la deuxième partie du chapitre 3, nous définissons un paramètre de temps invariant conforme pour chaque boucle appartenant à CLE(4) et nous donnons ensuite dans le chapitre 4 un couplage entre le champ libre Gaussien et l'ensemble CLE(4) à l'aide du paramètre de temps. Les processus SLE(k) peuvent être considérés comme les lignes de flot du champ libre Gaussien. Nous explicitons la dimension de Hausdorff de l'intersection de deux lignes de flot du champ libre Gaussien. Cela nous permet d'obtenir la dimension de l'ensemble des points de coupure et des points doubles de la courbe SLE, voir le chapitre 5. Dans le chapitre 6, nous définissons la mesure de restriction radiale, prouvons la caractérisation de ces mesures, et montrons la condition nécessaire et suffisante de l'existence des mesures de restriction radiale.

Dans ce travail, nous nous sommes intéressés d'une part à la théorie du chaos multiplicatif Gaussien introduite par Kahane en 1985 et d'autre part à la théorie des matrices aléatoires dont les pionniers sont Wigner, Wishart et Dyson. La première partie de ce manuscrit contient une brève introduction à ces deux théories ainsi que les contributions personnelles de ce manuscrit expliquées rapidement. Les parties suivantes contiennent les textes des articles publiés [1], [2], [3], [4], [5] et pré-publiés [6], [7], [8] sur ces résultats dans lesquels le lecteur pourra trouver des développements plus détaillés

The analysis of Human brain activity in magnetoencephalography (MEG) can be generally conducted in two ways: either by focusing on the average response evoked by a stimulus repeated over time, more commonly known as an ''event-related field'' (ERF), or by decomposing the signal into functionally relevant oscillatory or frequency bands (such as alpha, beta or gamma). However, the major part of brain activity is arrhythmic and these approaches fail in describing its complexity, particularly in resting-state. As an alternative, the analysis of the 1/f-type power spectrum observed in the very low frequencies, a hallmark of scale-free dynamics, can overcome these issues. Yet it remains unclear whether this scale-free property is functionally relevant and whether its fluctuations matter for behavior. To address this question, our first concern was to establish a visual learning paradigm that would entail functional plasticity during an MEG session. In order to optimize the training effects, we developed new audiovisual (AV) stimuli (an acoustic texture paired with a colored visual motion) that induced multisensory integration and indeed improved learning compared to visual training solely (V) or accompanied with acoustic noise (AVn). This led us to investigate the neural correlates of these three types of training using first a classical method such as the ERF analysis. After source reconstruction on each individual cortical surface using MNE-dSPM, the network involved in the task was identified at the group-level. The selective plasticity observed in the human motion area (hMT+) correlated across all individuals with the behavioral improvement and was supported by a larger network in AV comprising multisensory areas. On the basis of these findings, we further explored the links between the behavior and scale-free properties of these same source-reconstructed MEG signals. Although most studies restricted their analysis to the global measure of self-similarity (i.e. long-range fluctuations), we also considered local fluctuations (i.e. multifractality) by using the Wavelet Leader Based Multifractal Formalism (WLBMF). We found intertwined modulations of self-similarity and multifractality in the same cortical regions as those revealed by the ERF analysis. Most astonishing, the degree of multifractality observed in each individual converged during the training towards a single attractor that reflected the asymptotic behavioral performance in hMT+. Finally, these findings and their associated methodological issues are compared with the ones that came out from the ERF analysis.

Cette thèse en traitement d'images aborde le problème de la mise en évidence de certaines structures remarquables, comme des objets que nous percevons visuellement. Celles-ci peuvent être autant monodimensionnelles, comme des contours, que bidimensionnelles, ce qui correspond des objets plus complexes. Un problème important issu de la vision par ordinateur est de détecter de telles structures, ainsi que d'extraire des grandeurs caractéristiques de celles-ci. Dans diverses applications, comme la reconnaissance d'objets, l'appariement d'images, le suivi de mouvement ou le rehaussement de certains éléments particuliers, il s'agit d'une première étape avant d'autres opérations de plus haut niveau. Ainsi, la formulation de détecteurs performants apparaît comme essentielle. Nous montrons que cela peut être réalisé grâce des décompositions en ondelettes ; en particulier, il est possible de définir certaines lignes de maxima, qui s'avèrent pertinentes vis à vis de ce problème : d'une part, pour détecter des objets (par des régions d'intérêt), et, d'autre part, afin de les caractériser (calculs de régularité Lipschitzienne et d'échelle caractéristique). Cette approche originale de détection fondée sur des lignes de maxima peut alors être comparée aux approches classiques.