. . . . "Syst\u00E8me d'information g\u00E9ographique" . . . "This research introduces a qualitative spatial model for the description of a terrain silhouette, considered as either a profile or a frontier between Earth and the sky at the horizon. This model is based on the assumption that the conventional map paradigm is not adapted to cognitive representations, and then not appropriate for the development of our modelling approach. Instead the research presented follows the principles underlined by Naive Geography. We introduce a model where the main modelling primitives are considered as objects rather than geometric primitives. The model is also based on the assumption that the perception of a particular landform is dependent of the perception of saliencies defined as significant points of interest in the silhouette description. The description of a given silhouette includes topological relationships, and takes into account object indeterminate boundaries, and contains several levels of details derived from a mereological hierarchy. A prototype and interface implementation illustrates the potential of the approach, and allows for the integration of sample silhouettes and the computation of landform sequences." . . "Psychologie de la forme" . "Text" . "2008" . "Relief (g\u00E9ographie) -- Mod\u00E8les math\u00E9matiques" . . "Physique qualitative" . "Cette th\u00E8se d\u00E9veloppe un mod\u00E8le qualitatif de description d\u2019une silhouette de terrain telle que pourrait la percevoir un observateur situ\u00E9 au sol. Une silhouette repr\u00E9sente une s\u00E9paration terre / ciel \u00E0 l'horizon ou une coupe de terrain. Constatant que le paradigme cartographique n\u2019est pas adapt\u00E9 \u00E0 tous les modes de repr\u00E9sentation cognitifs de l\u2019espace, la th\u00E8se se positionne dans le courant de la G\u00E9ographie Na\u00EFve et introduit un mod\u00E8le de description des reliefs selon une approche s\u00E9mantique dont les primitives sont des objets signifiants et non plus des \u00E9l\u00E9ments g\u00E9om\u00E9triques as\u00E9mantiques. Ce mod\u00E8le repose sur le principe que la perception d'une forme particuli\u00E8re de relief est contingente de la perception de saillances, d\u00E9finies ici comme des points qualitativement remarquables. La description d'une silhouette inclut les relations topologiques qui relient les formes de relief d\u00E9tect\u00E9es, tient compte de l'impr\u00E9cision des fronti\u00E8res des objets g\u00E9ographiques et se d\u00E9cline \u00E0 diff\u00E9rents niveaux d'abstractions calcul\u00E9s selon une hi\u00E9rarchisation m\u00E9r\u00E9ologique. Un prototype a \u00E9t\u00E9 impl\u00E9ment\u00E9." . . . . . "A qualitative and semantic based approach for the description of landforms" . . "Th\u00E8ses et \u00E9crits acad\u00E9miques" . "Une approche qualitative spatiale pour une description s\u00E9mantique des reliefs" . "Une approche qualitative spatiale pour une description s\u00E9mantique des reliefs" . .