This study is concerned with the development of a practical and effective form of computer-aided analysis of the visual impact of building development in rural areas. Its contribution is fourfold. Firstly, a conceptual model has been developed for the process of seeing in the context of visual impact analysis. Secondly, a mathematical model for a consistent series of visual descriptors has been devised. Thirdly, a suitable design tool has been devised to make use of visual descriptors in visual impact analysis. Fourthly, visual descriptors have actually been implemented as computer software. The concept of visual impact analysis is defined and placed within the wider context of landscape research. The problems faced by a designer in the context of visual impact analysis are identified and the concept of a 'design tool' is introduced and defined. A number of existing computer software packages, intended or used for visual impact analysis, are reviewed critically. The concept of 'visual descriptors' as measures to be used by designers is introduced and examined critically. A conceptual model is presented for the process of seeing in the context of visual impact analysis. A range of possible measures for use as visual descriptors is presented and developed further into a series of precise definitions. A method of implementing visual descriptors is presented together with formal algorithms for the derivation of eight visual descriptors. A software package incorporating these descriptors is presented and verification and case studies of its use carried out. Visual descriptors, as implemented, are assessed for their effectiveness as a design tool for visual impact analysis.

Clinically it is important to combine information provided by mammographic images from multiple views or at different times. Taking regular mammographic screening and comparing corresponding mammograms are necessary for early detection of breast cancer, which is the key to successful treatment. However, mammograms taken at different times are often obtained under different compressions, orientations or body positions. A temporal pair of mammograms may vary quite significantly due to the spatial disparities caused by the variety in acquisition environments, including the 3D position of the breast, the amount of the pressure applied, etc. Such disparities can be corrected through the process of temporal registration. We have implemented and utilized finite element models for temporal registration of digital mammography. In our work, we applied the patient specific breast model, where patients have both mammograms and MRIs available, and generic model, where only patient mammograms are available. After we applied the temporal registration algorithm, the average error among the 14 patient datasets was 3.4 plus/minus 0.86 mm for Euclidean distance and 4.3 plus/minus 0.52 mm for predicted 2D lesion position. With generic model, the average error among the 14 patient datasets using the measure of Euclidean distance between the predicted lesion position in T1 and T2 was 5.0 plus/minus 0.74 mm for Euclidean distance and 5.7 plus/minus 0.83 mm for predicted 2D lesion position. Compared with the average lesion size (10mm~40mm), this error is acceptable. With lesion correspondence, our finite element method can be used to suppress technical variations (e.g., mammogram positioning or compression) and to emphasize genuine alterations in the breast.

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Cette thèse propose une analyse assistée par ordinateur des espaces imaginaires dans un corpus de littérature de jeunesse. Elle part du constat qu’il existe, dans ce genre littéraire particulier, une dualité dans la construction spatiale. En effet, on y trouve d’une part un espace quotidien (que Tolkien nomme monde primaire), et de l’autre un espace magique (le monde secondaire). Le périple du héros-enfant, qui prend la forme d’un ou de plusieurs aller-retours entre ces deux mondes, le conduit à grandir et à se métamorphoser. En ce sens, l’espace participe à sa transformation. Le parcours du protagoniste est jalonné de lieux et de motifs spatiaux récurrents dans le corpus tels que les maisons, les forêts, les jardins, les souterrains. Plus que de simples éléments de décors, ils apparaissent comme signifiants parce qu’ils traduisent à la fois les étapes nécessaires à la construction du héros et son état d’esprit. Il s’agit, dans cette perspective, de comprendre les enjeux symboliques de ces espaces imaginaires. L’étude de l’organisation des espaces narratifs à partir de données quantitatives montre qu’il existe une dualité entre les deux mondes, renforcée par une série de dichotomies. Malgré cet antagonisme structurel, le héros est capable de passer d’un univers à l’autre. L’analyse des modalités et des moments du passage de la frontière révèle que le monde secondaire est un espace mental et spirituel. En effet, il est à a fois l’espace du rêve, de la mort et du sacré. / This thesis is a computer-aided analysis of a corpus composed of twenty British children’s novels. It is based on the fact that, in this literary genre, space is organized by a structural opposition. Indeed, there is, on one hand, a daily environment (the primary world according to Tolkien) and, on the other hand, a magical space (the secondary world). The hero’s journey leads him to grow up and to metamorphose. In this respect, the narrative space is part of his transformation. The hero’s journey is marked out by a series of recurring places and motifs such as houses, forests, gardens and undergrounds. More than mere settings, they are meaningful because they reflect the protagonist’s state of mind. All these topographical elements are interdependent and constitute the spatial system of the narrative. The aim of this research is to understand what is symbolically at stake regarding imaginary spaces. The study of the spatial organization, based on quantitative data, shows a duality between the two worlds, emphasized by a series of dichotomies. Despite this structural antagonism, the hero is able to pass from one land to the other. Focusing on how and when the crossing of the border is possible reveals that the secondary world is a mental and spiritual space. Indeed, it is at the same time the land of dreams, of death and of the sacred.