Nowadays, there is a growing demand for personalization and the "one-size-fits-all" approach for hypermedia systems is no longer applicable. Adaptive hypermedia (AH) systems adapt their behavior to the needs of individual users. However due to the complexity of their authoring process and the different skills required from authors, only few of them have been proposed. These last years, numerous efforts have been put to propose assistance for authors to create their own AH. However, as explained in this thesis some problems remain.In this thesis, we tackle two particular problems. A first problem concerns the integration of authors' materials (information and user profile) into models of existing systems. Thus, allowing authors to directly reuse existing reasoning and execute it on their materials. We propose a semi-automatic merging/specialization process to integrate an author's model into a model of an existing system. Our objectives are twofold: to create a support for defining mappings between elements in a model of existing models and elements in the author's model and to help creating consistent and relevant models integrating the two models and taking into account the mappings between them.A second problem concerns the adaptation specification, which is famously the hardest part of the authoring process of adaptive web-based systems. We propose an EAP framework with three main contributions: a set of elementary adaptation patterns for the adaptive navigation, a typology organizing the proposed elementary adaptation patterns and a semi-automatic process to generate adaptation strategies based on the use and the combination of patterns. Our objectives are to define easily adaptation strategies at a high level by combining simple ones. Furthermore, we have studied the expressivity of some existing solutions allowing the specification of adaptation versus the EAP framework, discussing thus, based on this study, the pros and cons of various decisions in terms of the ideal way of defining an adaptation language. We propose a unified vision of adaptation and adaptation languages, based on the analysis of these solutions and our framework, as well as a study of the adaptation expressivity and the interoperability between them, resulting in an adaptation typology. The unified vision and adaptation typology are not limited to the solutions analysed, and can be used to compare and extend other approaches in the future. Besides these theoretical qualitative studies, this thesis also describes implementations and experimental evaluations of our contributions in an e-learning application.

Aujourd'hui, l’approche « one-size-fits-all » pour les hypermédias n'est plus applicable. Les Hypermédias Adaptatifs (AH) proposent d’adapter leur comportement aux besoins des utilisateurs. Cependant, en raison de la complexité de leur processus de création et des différentes compétences requises par les auteurs, peu d'entre eux ont été développés. Ces dernières années, de nombreux efforts ont été faits pour proposer d’aider les auteurs à créer leurs propres AH. mais certains problèmes demeurent non résolus.Nous nous sommes intéressées à deux problèmes particuliers.Le premier problème concerne l'intégration des ressources des auteurs dans des systèmes existants. Cela permet aux auteurs de réutiliser directement les adaptations prévues dans un système et de les exécuter sur leurs ressources. Pour répondre à ce problème, nous proposons un processus semi-automatique de fusion / spécialisation pour intégrer le modèle d'un auteur dans un modèle d'un système existant. Notre objectif est double: créer un support pour la définition des correspondances entre les éléments d’un modèle existant et ceux du modèle de l'auteur, et aider à créer un modèle cohérent intégrant les deux modèles et les correspondances entre eux. De cette façon, nous permettons aux auteurs d’intégrer leur modèle complet sans aucune transformation ni perte d’information. Le deuxième problème concerne la spécification de l'adaptation, qui est notoirement le processus le plus difficile dans la création des hypermédias adaptatifs. Nous proposons un framework EAP avec trois contributions principales : un ensemble de 22 patrons d'adaptation élémentaires pour l’adaptation de navigation, une typologie organisant les différents patrons d'adaptation élémentaires et un processus pour générer des stratégies d'adaptation basées sur l'utilisation et la combinaison semi-automatique des patrons d’adaptation élémentaires. Nos objectifs sont de permettre de définir facilement des stratégies d'adaptation à un niveau d’abstraction élevé en combinant des stratégies d’adaptation simples. Nous avons comparé l'expressivité du framework EAP à des solutions existantes, identifiant ainsi les avantages et les inconvénients des différentes décisions nécessaires à la définition d’un langage d'adaptation idéal. Nous proposons aussi une vision unifiée de l'adaptation et des langages d'adaptation, basée sur l’analyse de ces solutions et de notre framework, ainsi que sur l'étude de l'expressivité de l'adaptation et de l'interopérabilité entre les différentes solutions analysées. La vision unifiée sur l'adaptation n’est pas limitée aux solutions analysées. Elle peut être utilisée pour comparer et étendre d'autres approches.Outre ces études théoriques qualitatives, cette thèse décrit également des implémentations et des évaluations expérimentales. / Nowadays, there is a growing demand for personalization and the “one-size-fits-all” approach for hypermedia systems is no longer applicable. Adaptive hypermedia (AH) systems adapt their behavior to the needs of individual users. However due to the complexity of their authoring process and the different skills required from authors, only few of them have been proposed. These last years, numerous efforts have been put to propose assistance for authors to create their own AH. However, as explained in this thesis some problems remain.In this thesis, we tackle two particular problems. A first problem concerns the integration of authors’ materials (information and user profile) into models of existing systems. Thus, allowing authors to directly reuse existing reasoning and execute it on their materials. We propose a semi-automatic merging/specialization process to integrate an author’s model into a model of an existing system. Our objectives are twofold: to create a support for defining mappings between elements in a model of existing models and elements in the author’s model and to help creating consistent and relevant models integrating the two models and taking into account the mappings between them.A second problem concerns the adaptation specification, which is famously the hardest part of the authoring process of adaptive web-based systems. We propose an EAP framework with three main contributions: a set of elementary adaptation patterns for the adaptive navigation, a typology organizing the proposed elementary adaptation patterns and a semi-automatic process to generate adaptation strategies based on the use and the combination of patterns. Our objectives are to define easily adaptation strategies at a high level by combining simple ones. Furthermore, we have studied the expressivity of some existing solutions allowing the specification of adaptation versus the EAP framework, discussing thus, based on this study, the pros and cons of various decisions in terms of the ideal way of defining an adaptation language. We propose a unified vision of adaptation and adaptation languages, based on the analysis of these solutions and our framework, as well as a study of the adaptation expressivity and the interoperability between them, resulting in an adaptation typology. The unified vision and adaptation typology are not limited to the solutions analysed, and can be used to compare and extend other approaches in the future. Besides these theoretical qualitative studies, this thesis also describes implementations and experimental evaluations of our contributions in an e-learning application.