Near Field Communication (NFC) approach may be seen as a perspective way to improve user experience of quick data access with mobile devices to various services (secure payments, information exchange between users, etc.) in a city. This thesis concerns the topic of challenges which may be faced by interaction designers using this approach for creating a context-aware mobile solution for personalized data access in service-intensive urban environments. This research is based on considerations from researches, which explored which mobile information needs in particular seemed to be relevant for a modern user. Moreover, affordances and design blends concept are discussed in this work through a prism of the human-computer interaction in a city. ‘Research through design’ concept allowed performing the investigation of the given problem, starting from a user research, followed by prototyping an alternative solution and after - user evaluation of the prototype. Finally, a critical overview of the performed research gives suggestions for further improvement of the project.

Public services have been provided in an electronic format to reduce time and cost and to improve service quality. In this context, significant investments have been made since 2003 in Turkey and many government agencies started to provide services via the Internet. Government agencies need to learn the effectiveness of the offered services and the benefits of these services to citizens. The purposes of this thesis are to evaluate e-government websites in a comprehensive manner and to identify website design related problems. Especially, the study focuses on user-centered design of the e-government application. For this purpose, 33 e-government websites are evaluated, and an interview was conducted with eight government agencies websites&rsquo / designers. As a result of these studies, the problems encountered while using government electronic services are identified. Also, causes of these problems are found out. The study aims to provide a guideline in order to design user-centered e-government applications.

Cette thèse porte sur la conception de systèmes multi-agents ambiants pour faciliter l'autonomie et l'accessibilité aux espaces publics, en particulier aux personnes âgées. Le vieillissement de la population et l'accroissement des situations de handicap liées à la progression en âge, appellent une approche nouvelle de l'accessibilité des espaces publics urbains. Dans ce contexte, cette thèse propose la conception d'un dispositif outillé d'assistance aux personnes âgées dans leurs activités quotidiennes à l'extérieur qui s'adapte à l'environnement ouvert et évolutif de son usager. Pour permettre son acceptabilité, ce dispositif d'assistance ambiant s'appuie sur une démarche de conception centrée utilisateur, interdisciplinaire et collaborative. Un prototype a été réalisé et il offre une assistance en temps réel aux activités quotidiennes par apprentissage. En effet, il permet de détecter des anomalies dans le comportement, de notifier des alertes ou de proposer des recommandations. / The purpose of my thesis is to design and develop an ambient multi-agent system for seniors to increase their autonomy and their accessibility to public spaces. The ageing of the population and the increase of disability situations linked to age, call for a new approach to the accessibility of urban public spaces. In this context, this thesis provides a personalized system to assist elderly in their daily outdoor activities. It takes into account the openness and the evolution of the environment to which the system should adapt. In order to ensure its acceptability, this ambient sociotechnical system is based on a user-centered interdisciplinary collaborative design approach. A prototype has been implemented and it offers assistance in daily external activities thanks to learning. In fact, the system detects unusual situations and acts accordingly (notifications, alerts or recommendations).

<p><b><u>Introduction</u></b>: Mobile health applications (mHealth apps) have the potential to assist patients in adhering to their physician’s advice in chronic disease management through the use of persuasive nudge. However, systematically developing the persuasive features of a mHealth app for the major user demographic of older adults is challenging. The current usability engineering framework could ensure the user-friendliness of the app but not the persuasiveness. It is necessary to extend the current framework with appropriate measures to better understand the effectiveness of persuasive design elements in an iterative design process.</p><p> </p><p><b><u>Methods:</u></b> A pilot design project was run, a persuasive mHealth app for dietary management was developed using the user-centered design approach (persona, use scenario, task analysis, and cognitive walkthrough), the pilot testing result showed high potential of technology acceptance of older adults. To further evaluate persuasiveness, a food choice experimental protocol and human decision performance metrics based on Signal Detection Theory (SDT) were proposed. A mixed-methods, full factorial user testing study was conducted with twenty older adults aged over 60 and twenty students age 18-35. Critical persuasive User Interface (UI) design variables included decision paradigm (digital nudge), nutrition information format (information nudge), and the system default pre-selection (default nudge). The proposed SDT metrics to evaluate persuasiveness were then compared with confusion matrix metrics which are frequently used to validate system decision-making performance. The relationship between the human performance, subjective workload, and perceived usability of the proposed mHealth app was also investigated.</p><p> </p><p><b><u>Results:</u></b> The ‘Two Alternative Forced Choice’ layout significantly increased the d-prime and accuracy (persuasiveness), the system default pre-selection decreased persuasiveness. The interpretative FSA Nutri-scores label reduced time of response and workload, and increased perceived ease of use, perceived ease of learning, and satisfaction. Among older adults, results differed by age, computer proficiency, and health literacy.</p><p><b><u> </u></b></p><b><u>Conclusion:</u></b> The findings of this study imply the proposed framework is a valid persuasive design research approach. And digital nudge is an effective persuasive design for mHealth app, while default nudge may give rise to negative effects. A generalized human-centered digital nudge design framework along with ageing-centered guidelines were suggested for the similar research and design projects for persuasive technology performed in the future.

Les moteurs de recherche exploratoire (MRE) sont des logiciels aidant les utilisateurs à explorer un domaine d’intérêt pour y faire des découvertes. Ces moteurs se distinguent en cela des moteurs de recherche classiques tels que Google, Bing ou Yahoo!, lesquels supportent plutôt des recherches ciblées ou recherches de consultation (lookup). Si l’on admet que l’évaluation des MRE vise à vérifier si ces derniers aident effectivement les utilisateurs à réaliser leur tâche d’exploration, on constate que les méthodes existantes d’évaluation de ces systèmes ne permettent pas réellement cette vérification. L’une des raisons à cela est que ces méthodes ne reposent pas sur un modèle approprié de la recherche exploratoire (RE) ou qu’elles restent accrochées à un modèle de la recherche de consultation. L’objectif principal de cette thèse est de proposer aux concepteurs de ces MRE des méthodes d’évaluation centrées utilisateurs reposant sur un modèle du processus de RE. Ainsi, après avoir modélisé le processus de RE, nous proposons deux méthodes d’évaluation qui peuvent être utilisées tout au long du processus de conception. La première méthode, une méthode d’inspection sans utilisateurs, peut être utilisée dès les premières maquettes, et repose sur des heuristiques de RE. Nous avons également proposé des outils facilitant l’utilisation de ces heuristiques : un formulaire en ligne ainsi qu’une extension Google Chrome appelée CheXplore. La seconde méthode, avec utilisateurs, peut être utilisée dès la première version d’un prototype fonctionnel. Cette méthode se présente comme une procédure de test utilisateur personnalisable. Dans cette thèse, nous nous intéressons plus particulièrement à deux éléments de cette procédure : un protocole d’élaboration de tâches de RE et une grille d’analyse d’enregistrements vidéo de session de RE. La pertinence du modèle ainsi que les méthodes qui en découlent ont été évaluées à l’occasion de tests utilisateurs. Le modèle, les heuristiques et le protocole d’élaboration des tâches de RE ont été validés. Les premières évaluations de la grille d’analyse d’enregistrements vidéos ont révélé des points à améliorer. / Exploratory search systems are search engines that help users to explore a topic of interest. A shortcoming of current evaluation methods is that they cannot be used to determine if an exploratory search system can effectively help the user in performing exploratory search tasks. Indeed, the assessment cannot be the same between classic search systems (such as Google, Bing, Yahoo!...) and exploratory search systems. The complexity and the difficulty to have a consensus definition of the exploratory search concept and process are reflected in the difficulties to evaluate such systems. Indeed, they combine several specifics features and behaviors forming an alchemy difficult to evaluate. The main objective of this thesis is to propose for the designers of these systems (i.e. computer scientists) user-centered evaluation methods of exploratory search systems. These methods are based on a model of exploratory search process in order to help the evaluators to verify if a given system supports effectively the exploratory search process. Thus, after elaborating a model of exploratory search process, we propose two model-based methods, with and without users, which can be used all along the design process. The first method, without users, can be used from the first sketch of the system, consists of a set of heuristics of exploratory search and a procedure for using them. We also propose two tools facilitating their use: an online form format and an Google Chrome plugin, CheXplore. The second method involves real end-users of exploratory search systems who test a functional prototype or version of an exploratory search system. In this thesis, we mainly focus on two model-based elements of a customizable user testing procedure: a protocol for the elaboration of exploratory search tasks and a video analysis grid for the evaluation of recorded exploratory search sessions.