Thesis (M.S.)--Naval Postgraduate School. / "March 2007." Includes bibliographical references (p. 37). Also available online from the Web site of the Naval Postgraduate School (http://www.nps.edu).

Thesis (M. Eng.(Electronic engineering))-University of Pretoria, 2006. / Includes bibliographical references. Available on the Internet via the World Wide Web.

Th. doct.--Hist.--Paris--Faculté des Lettres et sciences humaines, 1957. / Notes bibliogr. Index.

Texte remanié de: Tesis de doctorado--Universidad de Cádiz, 1995. / Contient de nombreux documents de l'époque. Bibliogr. p. 495-498. Index.

Une étude de Nielsen (2006), largement citée, indique que les internautes explorent les pages Web suivant un pattern en forme de "F". Ce résultat a amené les concepteurs à organiser les informations d'une page en fonction de ce comportement, même si aucune étude n'a permis de répliquer ces résultats. Bien que les conclusions de cette étude portent sur le comportement visuel, la question des patterns comportementaux permettant de décrire la navigation des internautes se pose de manière plus générale. L'objectif de cette thèse a donc été de déterminer si des patterns pouvaient être mis en lumière à partir de différents indicateurs. Trois études ont été réalisées. Dans la première étude, 112 participants devaient réaliser quatre tâches de recherche d’information sur deux sites web différents. Le protocole impliquait une répétition immédiate de ces mêmes tâches. Une classification automatique a permis d'identifier 4 patterns qui se distinguent à la fois en termes de navigation sur la page d’accueil, mais aussi de performances. Lors des répétitions, la classification nous a permis d’identifier 3 des 4 patterns précédents. Ceci implique que les individus ne répètent pas forcément leur façon de rechercher l'information et ceci, peu importe la tâche, et le site. La deuxième étude a porté sur 27 individus et impliquait, pour les participants, de se présenter trois fois consécutives à 48 heures d’intervalle, afin de refaire les mêmes tâches. La répétition des tâches, que ce soit à court ou à moyen terme, entraîne une augmentation des performances, c'est-à-dire que les tâches sont réalisées plus rapidement et de façon plus efficiente. Toutefois, les patterns identifiés diffèrent entre les répétitions à court et moyen terme. Un autre résultat observé est que les stratégies ou patterns ne sont pas propres aux individus. En d'autres termes, un individu peut présenter ou adopter plusieurs patterns d'une tâche à une autre, d'un site à un autre ou d'une répétition à l'autre. Enfin, pour notre dernière étude, nous nous sommes demandé si l’homogénéité de nos échantillons pouvait influer sur les patterns. Nous avons donc réalisé une expérimentation comptant 47 participants avec des profils variés. Les individus ont eu tendance à se distinguer selon les 4 mêmes patterns identifiés. Nous avons pu observer qu’en fonction des individus, une même stratégie pouvait conduire à la réussite ou à l’échec de la tâche. De plus, les styles d’apprentissage ne semblent pas liés aux patterns observés. Les limites et les perspectives de ces travaux sont discutées. / A study by Nielsen (2006), widely cited, indicates that Internet users explore web pages following a "F" shape pattern. This result brought the designers to organize the information of a page according to this behavior, even if no study replicated these results. Although the conclusions of this study concern the visual behavior, the question of the behavioral patterns allowing describing the navigation of the Internet users remains in a more general way. Thus the aim of this thesis was to determine if patterns could be revealed from various indicators. Three studies were conducted. In the first study, 112 participants had to perform four information search tasks on two different websites. The experimental protocol involved an immediate repetition of the same tasks. A clustering method allowed us to identify 4 behavioral patterns, which distinguish themselves in terms of navigation on the homepage, but also in terms of performances. During the repetitions, the classification allowed us to identify 3 patterns out of the 4 previous ones. This implies that the individuals do not repeat necessarily the way they look for the information and this, no matter the task, and the Web site. The second experiment involved 27 persons. They had to come three times, with 48 hour intervals to repeat the same tasks. The repetition of the tasks, whether in short or medium-term, increased the performances of the users, that is the tasks are more quickly realized and in a more efficient way. However, the identified patterns differ between the short and medium-term repetitions. Another observed result is that the strategies or patterns are not peculiar to the individuals. In other words, an individual can present or adopt several patterns from a task to another one, from a site to an other one or from a repetition to the other one. Finally, in our last study, we wondered if the homogeneity of our previous samples could have influenced the patterns. So we conducted an experiment with 47 participants with varied profiles. The individuals tended to distinguish themselves according to 4 same identified patterns. We were able to observe that according to the individuals, the same strategy could lead to the success or to the failure of the task. Furthermore, the learning styles did not seem to be related to the observed patterns. Limits and prospects of this work are discussed.

Humans today rely heavily on navigational aids on their smartphones to find their way. These aids have shown to be decreasing our ability to learn routes since the interaction with the environment is minimal. Technology assisting indoor navigation is getting more common, and the same approach, which has shown to impair spatial ability, is used, and will most likely result in the same problems. In the current study an application was developed that uses landmarks represented as icons to guide the users. The application was tested in a wayfinding task and compared to a control group using text instructions. Time for completing the route, wayfinding errors and route knowledge were measured and compared between groups. The results show that the text group had a faster walking time, but no significant difference was found in the other measurement. The route knowledge test turned out to be too difficult for the participants. The conclusion of the study is that icon based indoor navigation works but more research needs to be done to test if it facilitates spatial learning

According to the Canadian Cancer Society, half of Ontario’s population will be diagnosed with cancer in their lifetime. Many patients being assessed for cancer however become overwhelmed when having to manage information overload, many appointments with different instructions and locations, and recommendations on how to improve their lifestyle. This causes much anxiety and uncertainty among patients. Some cancer assessment clinics offer some guidance in the form of paper-based patient navigators, which provide much reliable information to patients but are limited in terms of dynamic updates to appointments, opportunities for sharing knowledge between healthcare providers and patients, and of patients supporting each other. This thesis proposes a new web-based, mobile, and user-friendly virtual patient navigator application framework named Care Ami, which incorporates the information found in an existing paper-based navigator along with the new features such as remote updates to personal care paths and calendars, personalized navigation guidance, sharing of symptoms/medications information, and peer group support. Unlike existing solutions, Care Ami is configurable to support multiple types of diseases (e.g., lung cancer and breast cancer). This application is evaluated through testing and the usage of heuristic evaluation guidelines related to usability, and a comparison with related work highlights its many benefits.

The aim of this paper is to examine how Tanums kommuns website's global navigation menu, local menu and search engine can get better and how to improve them. I have chosen to use usability testing, surveys and research about similar products in order to find out how this can be done. I have found that the website has problems with not getting results when searching in a specific way. I have also found, among other things, that users don't find it logical to find certain information at some places and also that the labeling of certain elements in the menu needs improvement. A few of my suggestions were to help the user by suggesting different ways to search, that there is a way to filter the search, that the labeling of the menu elements were looked through and that information were put where users finds it logical. I also suggested that a bigger usability test could be carried out before or after some changes to the website was done.

This thesis is a brief look at a new solution to a problem that has been approached in many different ways in the past - the N body problem. By focusing on planetary systems, satellite dynamics can be modeled in a fashion similar to the Circular Restricted Three Body Problem (CR3BP) with the Circular Restricted N Body Problem (CRNBP). It was found that this new formulation of the dynamics can then utilize the tools created from all the research into the CR3BP to reassess the possibility of different complex trajectories in systems where there are more than just two large gravitational bodies affecting the dynamics, namely periodic and semi-periodic orbits, halo orbits, and low energy transfers It was also found that not only system dynamics, but models of the Jacobi constant could also be formulated similarly to the CR3BP. Validating the authenticity of these new sets of equations, the CRNBP dynamics are applied to a satellite in the Earth-Moon system and compared to a simulation of the CR3BP under identical circumstances. This test verified the dynamics of the CRNBP, showing that the two systems created almost identical results with relatively small deviations over time and with essentially identical path trends. In the Jovian system, it was found the mass ratio required to validated the assumptions required to integrate the equations of motion was around .1$\%$. Once the mass ratio grew past that limit, trajectories propagated with the CRNBP showed significant deviation from trajectories propagated with a higher fidelity model of Newtonian motion. The results from the derivation of the Jacobi constant are consistent with the 3 body system, but they are fairly standalone.

Unmanned ground vehicles (UGVs) have been widely used in many areas such as agriculture, mining, construction and military applications. This results from the fact that UGVs can not only be easily built and controlled, but also be featured with high mobility and handling hazardous situations in complex environments. Among the competences of UGVs, autonomous navigation is one of the most challenging problems. This is because that the success in achieving autonomous navigation depends on four factors: Perception, localization, cognition, and proper motion controller. In this thesis, we introduce the realization of autonomous navigation for a two-wheeled differential ground robot under the robot operating system (ROS) environment from both the simulation and experimental perspectives. In Chapter 2, the simulation work is discussed. Firstly, the robot model is described in the unified robot description format (URDF)-based form and the working environment for the robot is simulated. Then we use the \textit{gmapping} package which is one of the packages integrating simultaneous localization and mapping (SLAM) algorithm to build the map of the working environment. In addition, ROS packages including \textit{tf}, \textit{move\_base}, \textit{amcl}, etc., are used to realize the autonomous navigation. Finally, simulation results show the feasibility and effectiveness of the autonomous navigation system for the two-wheeled UGV with the ability to avoid collisions with obstacles. In Chapter 3, we introduce the experimental studies of implementing autonomous navigation for a two-wheeled UGV. The necessary hardware peripherals on the UGV to achieve autonomous navigation are given. The process of implementation in the experiment is similar to that in simulation, however, calibration of several devices is necessary to adapt the scenario in a practical environment. Additionally, a proportional-integral-derivative (PID) controller for the robot base is used to handle the external noise during the experiment. The experimental results demonstrate the success in the implementation of autonomous navigation for the UGV in practice. / Graduate