Cette thèse examine les notions de représentations sociales et de rapport à l'écriture (Barré-De Miniac 2000), situées dans un contexte plurilingue. Le premier enjeu de la thèse est de réinvestir ces notions issues de la didactique du français langue maternelle (LM) dans le contexte plurilingue d'un programme de français dans une université en Australie. Le deuxième enjeu est d'analyser l'évolution de la capacité scripturale des apprenants de la deuxième année à la quatrième année de français et de comparer la description de leurs processus d'écriture en LM et en langue étrangère (LE). L'objectif est de saisir l'activité scripturale dans ses dimensions psychologique, sociale et cognitive. L'analyse du topic (Berthoud 1996) réalisée sur le corpus discursif des enseignants (à partir d'entretiens individuels) montre les limites de la notion de rapport à l'écriture dans un contexte plurilingue et a permis de dégager une notion centrale dans cette situation d'enseignement : le rapport à la langue étrangère apprise. L'analyse du topic réalisée sur le corpus discursif des apprenants (groupes de discussion) indique que leur travail d'écriture en LE commence par celui des idées, et que le passage à l'écriture en LE s'avère un moment privilégié de prise de conscience des phénomènes langagiers par le fait que cet instant d'écriture active la connaissance de deux ou plusieurs langues. Cette situation de transition entre les langues, rendue plus aiguë par l'écriture, est rapprochée de la zone prochaine de développement (ZPD) de la théorie socioculturelle de Vygotski dans la mesure où sont mises en évidence l'élaboration de stratégies d'apprentissage et l'intériorisation de la langue dans ce travail de négociation. La comparaison des procédures d'écriture en LE et celles en LM indique que l'attention porte sur des points différents d'écriture selon le niveau de l'apprenant. L'analyse des données scripturales se subdivise en trois parties. Premièrement, sont extraits des consignes rédactionnelles les aspects qui renforcent la littératie en LE par l'écrit. Deuxièmement, les productions écrites proposent une autre entrée sur le rapport à l'écriture des apprenants. Analysées à partir d'une approche basée sur la linguistique systémique fonctionnelle de M. K. Halliday pour déterminer l'investissement des scripteurs dans leurs productions, elles démontrent un investissement différent du scripteur selon son niveau de langue. Enfin, l'analyse des annotations des lecteurs évaluateurs établit la continuité des topics élaborés au niveau discursif dans le corpus scriptural, et met en évidence que les annotations appuient surtout le rapport à la langue. L'analyse des données orales et scripturales dans un contexte plurilingue a permis d'observer le rapport à l'écriture par la saisie de la continuité du topic sur l'ensemble du corpus et contribue à préciser théoriquement la notion utilisée dans un contexte universitaire plurilingue par la mise en évidence des notions telles que le rapport à la langue, le rapport à l'apprentissage, et celle de passage entre les langues.

<p>In Western society, food is debated and in various ways contested. Social science research has described various cultural imperatives related to food and choices of diet, that raises questions about how people understand issues of food and eating in their everyday lives. The aim of this study is to explore everyday notions of food and eating in urban Sweden. Drawing on social representations theory, qualitative interviews were carried out with fifteen men and women about their experiences and understandings of food and eating, also using a photo-elicitation method where visual material from cookery books and dietary advice were used as a point of departure for the interview conversation.</p><p>The interviewees categorize food into different sorts, such as ‘ordinary food’, ‘modern food’, ‘dangerous food’, ‘healthy food’, ‘ethic food’ and ‘festive food’, that are ascribed a meaning in relation to different arenas in time and space, for instance childhood, and related to health values as well as ethical and aesthetic values. Food is also discussed as different diets, such as mixed or vegetarian, and patterns of eating, which are in turn related to risk, health and the body. The analysis thus reveal notions about what food is and how we should eat, notions that are characterised by internal tensions and contradictions such as discipline contra pleasure, societal norms contra personal interests, everyday life contra ideals. These ‘fields of tension’ are analysed as a cultural repertoire of identity-positions. Finally, these results are discussed in terms of risk and opportunities, where the reflexive human being is depicted as able to both incorporate food imperatives and to challenge these imperatives in a process of striving for bodily and mental balance.</p>

<p>This thesis aims to find a graph structure for representing XML documents and to implement the former representation for storing such documents. The graph structure, in fact, is the complete representation for the XML documents; this is dued to the id/idref attribute which could be present inside the XML document tag.</p><p>Two different graph structures have been defined on this thesis, they are called most granular and customizable representations. The first one is the simplest way for representing XML documents, while the second one makes some improvements for optimizing inserting, deleting, and querying functions.</p><p>The implementation of the former graph structures is made over a new kind of database built specifically for storing semi-structured data, such database is called Neo. Neo database works only with three primitives: node, relationship, and property. Such data model represents a new solution compared to the traditional relational view.</p><p>The XML information manager implements two different API which work with the two former graph structure respectively. The first API works with the customizable representation, while the second one works with the customizable representation.</p><p>Some evaluations have been done over the second implemented API, and they showed that the implemented code is free of bugs and moreover that the customizable representation brings about some improvements on making queries over the stored data.</p>

<p>This thesis demonstrates that infants represent temporarily non-visible, or occluded, objects. From 4 months of age, infants could accurately predict the reappearance of a moving object after 660 ms of non visibility; indicating accurate spatiotemporal representations. At this age predictions were dominated by associations between specific events and outcomes (associative rules). Between 6 and 8 months of age predictions became dominated by extrapolations (Study III). From 6 months infants could represent occluded objects for up to 4 seconds. The number of successful predictions decreased, however, if the information contained in the occlusion event diminished (time of accretion and deletion). As infants grew older (up to 12 months) they produced more accurate predictions. (Study II). The similarities between adult and infant performances were numerous (Study I). These conclusion are based on one cross sectional (Study I) and two longitudinal studies (Study II & III) in which an object, a ‘happy face’, moved on circular (Study I, II, & III) and other complex trajectories (Study III). One portion of each trajectory was covered by a screen that blocked the object from sight. In each study participants gaze were recorded with an infrared eye tracking system (ASL 504) and a magnetic head tracker (Flock of Birds). This data was combined with data from the stimulus and stored for of line analysis.</p>

<p>In this thesis we introduce and study a notion of effectivity (or computability) for test functions and for distributions. This is done using the theory of effective (Scott-Ershov) domains and effective domain representations.</p><p>To be able to construct effective domain representations of the spaces of test functions considered in distribution theory we need to develop the theory of admissible domain representations over countable pseudobases. This is done in the first paper of the thesis. To construct an effective domain representation of the space of distributions, we introduce and develop a notion of partial continuous function on domains. This is done in the second paper of the thesis. In the third paper we apply the results from the first two papers to develop an effective theory of distributions using effective domains. We prove that the vector space operations on each space, as well as the standard embeddings into the space of distributions effectivise. We also prove that the Fourier transform (as well as its inverse) on the space of tempered distributions is effective. Finally, we show how to use convolution to compute primitives on the space of distributions. In the last paper we investigate the effective properties of a structure theorem for the space of distributions with compact support. We show that each of the four characterisations of the class of compactly supported distributions in the structure theorem gives rise to an effective domain representation of the space. We then use effective reductions (and Turing-reductions) to study the reducibility properties of these four representations. We prove that three of the four representations are effectively equivalent, and furthermore, that all four representations are Turing-equivalent. Finally, we consider a similar structure theorem for the space of distributions supported at 0.</p>

Computational modules early in the human vision system typically generate sparse information about the shapes of visible surfaces in the scene. Moreover, visual processes such as stereopsis can provide such information at a number of levels spanning a range of resolutions. In this paper, we extend this multi-level structure to encompass the subsequent task of reconstructing full surface descriptions from the sparse information. The mathematical development proceeds in three steps. First, the surface most consistent with the sparse constraints is characterized as the solution to an equilibrium state of a thin flexible plate. Second, local, finite element representations of surfaces are introduced and, by applying the finite element method, the continuous variational principle is transformed into a discrete problem in the form of a large system of linear algebraic equations whose solution is computable by local-support, cooperative mechanisms. Third, to exploit the information available at each level of resolution, a hierarchy of discrete problems is formulated and a highly efficient multi-level algorithm, involving both intra-level relaxation processes and bi-directional inter-level algorithm, involving both intra-level relaxation processes and bidirectional inter-level local interpolation processes is applied to their simultaneous solution.. Examples of the generation of hierarchies of surface representations from stereo constraints are given. Finally, the basic surface approximation problem is revisited in a broader mathematical context whose implications are of relevance to vision.

This thesis demonstrates that infants represent temporarily non-visible, or occluded, objects. From 4 months of age, infants could accurately predict the reappearance of a moving object after 660 ms of non visibility; indicating accurate spatiotemporal representations. At this age predictions were dominated by associations between specific events and outcomes (associative rules). Between 6 and 8 months of age predictions became dominated by extrapolations (Study III). From 6 months infants could represent occluded objects for up to 4 seconds. The number of successful predictions decreased, however, if the information contained in the occlusion event diminished (time of accretion and deletion). As infants grew older (up to 12 months) they produced more accurate predictions. (Study II). The similarities between adult and infant performances were numerous (Study I). These conclusion are based on one cross sectional (Study I) and two longitudinal studies (Study II &amp; III) in which an object, a ‘happy face’, moved on circular (Study I, II, &amp; III) and other complex trajectories (Study III). One portion of each trajectory was covered by a screen that blocked the object from sight. In each study participants gaze were recorded with an infrared eye tracking system (ASL 504) and a magnetic head tracker (Flock of Birds). This data was combined with data from the stimulus and stored for of line analysis.

In Western society, food is debated and in various ways contested. Social science research has described various cultural imperatives related to food and choices of diet, that raises questions about how people understand issues of food and eating in their everyday lives. The aim of this study is to explore everyday notions of food and eating in urban Sweden. Drawing on social representations theory, qualitative interviews were carried out with fifteen men and women about their experiences and understandings of food and eating, also using a photo-elicitation method where visual material from cookery books and dietary advice were used as a point of departure for the interview conversation. The interviewees categorize food into different sorts, such as ‘ordinary food’, ‘modern food’, ‘dangerous food’, ‘healthy food’, ‘ethic food’ and ‘festive food’, that are ascribed a meaning in relation to different arenas in time and space, for instance childhood, and related to health values as well as ethical and aesthetic values. Food is also discussed as different diets, such as mixed or vegetarian, and patterns of eating, which are in turn related to risk, health and the body. The analysis thus reveal notions about what food is and how we should eat, notions that are characterised by internal tensions and contradictions such as discipline contra pleasure, societal norms contra personal interests, everyday life contra ideals. These ‘fields of tension’ are analysed as a cultural repertoire of identity-positions. Finally, these results are discussed in terms of risk and opportunities, where the reflexive human being is depicted as able to both incorporate food imperatives and to challenge these imperatives in a process of striving for bodily and mental balance.

In this thesis we introduce and study a notion of effectivity (or computability) for test functions and for distributions. This is done using the theory of effective (Scott-Ershov) domains and effective domain representations. To be able to construct effective domain representations of the spaces of test functions considered in distribution theory we need to develop the theory of admissible domain representations over countable pseudobases. This is done in the first paper of the thesis. To construct an effective domain representation of the space of distributions, we introduce and develop a notion of partial continuous function on domains. This is done in the second paper of the thesis. In the third paper we apply the results from the first two papers to develop an effective theory of distributions using effective domains. We prove that the vector space operations on each space, as well as the standard embeddings into the space of distributions effectivise. We also prove that the Fourier transform (as well as its inverse) on the space of tempered distributions is effective. Finally, we show how to use convolution to compute primitives on the space of distributions. In the last paper we investigate the effective properties of a structure theorem for the space of distributions with compact support. We show that each of the four characterisations of the class of compactly supported distributions in the structure theorem gives rise to an effective domain representation of the space. We then use effective reductions (and Turing-reductions) to study the reducibility properties of these four representations. We prove that three of the four representations are effectively equivalent, and furthermore, that all four representations are Turing-equivalent. Finally, we consider a similar structure theorem for the space of distributions supported at 0.

This thesis studies two topics in sequence analysis. In the first part, we investigate the large deviations of the shape of the random RSK Young diagrams, associated with a random word of size n whose letters are independently drawn from an alphabet of size m=m(n). When the letters are drawn uniformly and when both n and m converge together to infinity, m not growing too fast with respect to n, the large deviations of the shape of the Young diagrams are shown to be the same as that of the spectrum of the traceless GUE. Since the length of the top row of the Young diagrams is the length of the longest (weakly) increasing subsequence of the random word, the corresponding large deviations follow. When the letters are drawn with non-uniform probability, a control of both highest probabilities will ensure that the length of the top row of the diagrams satisfies a large deviation principle. In either case, both speeds and rate functions are identified. To complete our study, non-asymptotic concentration bounds for the length of the top row of the diagrams, are obtained for both models. In the second part, we investigate the order of the r-th, 1<= r < +∞, central moment of the length of the longest common subsequence of two independent random words of size n whose letters are identically distributed and independently drawn from a finite alphabet. When all but one of the letters are drawn with small probabilities, which depend on the size of the alphabet, the r-th central moment is shown to be of order n^{r/2}. In particular, when r=2, we get the order of the variance of the longest common subsequence.