As one of the main topics in Virtual Reality (VR), travel interfaces have been studied by many researchers in the past decades. However, it is still a challenging topic today. One of the design problems is the tradeoff between speed and precision. Some tasks (e.g., driving) require a user to travel long distances with less concern about precise movement, while other tasks (e.g., walking) require users to approach nearby objects in a more precise way, and to care less about the speed. Between these two extremes there are scenarios when both speed and precision become equally important. In the real world, we often seamlessly balance these requirements. However, most VR systems only support a single travel mode, which may be good for one range of travel, but not others. We propose and evaluate a new VR travel framework which supports three separate multi-touch travel techniques for different distance ranges, that all use the same input device with a unifying metaphor of the user’s fingers becoming their legs. We investigate the usability and user acceptance for the fingers-as-legs metaphor, as well as the efficiency, naturalness, and impact on spatial awareness such an interface has.

Scientific visualization is primarily concerned with the visual presentation of three-dimensional phenomena in domains like medicine, meteorology, astrophysics, etc. The emphasis in scientific visualization research has been on the efficient rendering of measured or simulated data points, surfaces, volumes, and a time component to convey the dynamic nature of the studied phenomena. With the explosive growth in the size of the data, interactive visualization of scientific data becomes a real challenge. In recent years, the graphics community has witnessed tremendous improvements in the performance capabilities of graphics processing units (GPUs), and advances in GPU-accelerated rendering have enabled data exploration at interactive rates. Nevertheless, the majority of techniques rely on the assumption that a true three-dimensional geometric model capturing physical phenomena of interest, is available and ready for visualization. Unfortunately, this assumption does not hold true in many scientific domains, in which measurements are obtained from a given scanning modality at sparsely located intervals in both space and time. This calls for the fusion of data collected from multiple sources in order to fill the gaps and tell the story behind the data. For years, data fusion has relied on machine learning techniques to combine data from multiple modalities, reconstruct missing information, and track features of interest through time. However, these techniques fall short in solving the problem for datasets with large spatio-temporal gaps. This realization has led researchers in the data fusion domain to acknowledge the importance of human-in-the-loop methods where human expertise plays a major role in data reconstruction. This PhD research focuses on developing visualization and interaction techniques aimed at addressing some of the challenges that experts are faced with when analyzing the spatio-temporal behavior of physical phenomena. Given a number of datasets obtained from different measurement modalities and from simulation, we propose a generalized framework that can guide research in the field of multi-sensor data fusion and visualization. We advocate the use of GPU parallelism in our developed techniques in order to emphasize interaction as a key component in the successful exploration and analysis of multi-sourced data sets. The goal is to allow the user to create a mental model that captures their understanding of the spatio-temporal behavior of features of interest; one which they can test against real data measurements to verify their model. This model creation and verification is an iterative process in which the user interacts with the visualization, explores and builds an understanding of what occurred in the data, then tests this understanding against real-world measurements and improves it. We developed a system as a reference implementation of the proposed framework. Reconstructed data is rendered in a way that completes the users' cognitive model, which encodes their understanding of the phenomena in question with a high degree of accuracy. We tested the usability of the system and evaluated its support for this cognitive model construction process. Once an acceptable model is constructed, it is fed back to the system in the form of a reference dataset, which our framework uses to guide the real-time tracking of measurement data. Our results show that interactive exploration tasks enable the construction of this cognitive model and reference set, and that real-time interaction is achievable during the exploration, reconstruction, and enhancement of multi-modal time-variant three-dimensional data, by designing and implementing advanced GPU-based visualization techniques. / Ph. D.

No / It is becoming increasingly popular to expose government and citywide sensor data as linked data. Linked data appears to offer a great potential for exploratory search in supporting smart city goals of helping users to learn and make sense of complex and heterogeneous data. However, there are no systematic user studies to provide an insight of how browsing through linked data can support exploratory search. This paper presents a user study that draws on methodological and empirical underpinning from relevant exploratory search studies. The authors have developed a linked data browser that provides an interface for user browsing through several datasets linked via domain ontologies. In a systematic study that is qualitative and exploratory in nature, they have been able to get an insight on central issues related to exploratory search and browsing through linked data. The study identifies obstacles and challenges related to exploratory search using linked data and draws heuristics for future improvements. The authors also report main problems experienced by users while conducting exploratory search tasks, based on which requirements for algorithmic support to address the observed issues are elicited. The approach and lessons learnt can facilitate future work in browsing of linked data, and points at further issues that have to be addressed.

User interaction in visual analytic systems is critical to enabling visual data exploration. Through interacting with visualizations, users engage in sensemaking, a process of developing and understanding relationships within datasets through foraging and synthesis. For example, two-dimensional layouts of high-dimensional data can be generated by dimension reduction models, and provide users with an overview of the relationships between information. However, exploring such spatializations can require expertise with the internal mechanisms and parameters of these models. The core contribution of this work is semantic interaction, capable of steering such models without requiring expertise in dimension reduction models, but instead leveraging the domain expertise of the user. Semantic interaction infers the analytical reasoning of the user with model updates, steering the dimension reduction model for visual data exploration. As such, it is an approach to user interaction that leverages interactions designed for synthesis, and couples them with the underlying mathematical model to provide computational support for foraging. As a result, semantic interaction performs incremental model learning to enable synergy between the user's insights and the mathematical model. The contributions of this work are organized by providing a description of the principles of semantic interaction, providing design guidelines through the development of a visual analytic prototype, ForceSPIRE, and the evaluation of the impact of semantic interaction on the analytic process. The positive results of semantic interaction open a fundamentally new design space for designing user interactions in visual analytic systems. This research was funded in part by the National Science Foundation, CCF-0937071 and CCF-0937133, the Institute for Critical Technology and Applied Science at Virginia Tech, and the National Geospatial-Intelligence Agency contract #HMI1582-05-1-2001. / Ph. D.

Learning from text data often involves a loop of tasks that iterate between foraging for information and synthesizing it in incremental hypotheses. Past research has shown the advantages of using spatial workspaces as a means for synthesizing information through externalizing hypotheses and creating spatial schemas. However, spatializing the entirety of datasets becomes prohibitive as the number of documents available to the analysts grows, particularly when only a small subset are relevant to the tasks at hand. To address this issue, we developed the multi-model semantic interaction (MSI) technique, which leverages user interactions to aid in the display layout (as was seen in previous semantic interaction work), forage for new, relevant documents as implied by the interactions, and then place them in context of the user's existing spatial layout. This results in the ability for the user to conduct both implicit queries and traditional explicit searches. A comparative user study of StarSPIRE discovered that while adding implicit querying did not impact the quality of the foraging, it enabled users to 1) synthesize more information than users with only explicit querying, 2) externalize more hypotheses, 3) complete more synthesis-related semantic interactions. Also, 18% of relevant documents were found by implicitly generated queries when given the option. StarSPIRE has also been integrated with web-based search engines, allowing users to work across vastly different levels of data scale to complete exploratory data analysis tasks (e.g. literature review, investigative journalism). The core contribution of this work is multi-model semantic interaction (MSI) for usable big data analytics. This work has expanded the understanding of how user interactions can be interpreted and mapped to underlying models to steer multiple algorithms simultaneously and at varying levels of data scale. This is represented in an extendable multi-model semantic interaction pipeline. The lessons learned from this dissertation work can be applied to other visual analytics systems, promoting direct manipulation of the data in context of the visualization rather than tweaking algorithmic parameters and creating usable and intuitive interfaces for big data analytics. / Ph. D.

This dissertation investigates the interplay between a selected set of museum practices, such as online strategies, digitisation of artwork reproductions, and crowdsourcing, through a theoretically grounded perspective. Existing discourse and debate on the museum's movement from an exclusively physical, to a digital or hybrid presence display an excessive interest in advocacy, usually focusing on small examples of successful practices which are then argued as somehow empowering or resolutive, usually from a 'social justice' point of view. Conversely, in those same discourses little attention is paid to the macro-context within which these cases take place: current debates lack an articulation of how museum practices reflect ongoing trends and paradigms on a culture-wide level, and also eschew non-advocative, neutral discussion of the politics, discourses and power relations that such practice entail. I suggest that the contemporary constructivist, digital museum can be better contextualised if we frame emergent digital museum praxis within a framework that resorts to well-established, and well-described theoretical paradigms that can be observed in other cultural and social contexts as well. The advantage of such an approach is that museum practice, and the museum as an institution, can then be seen in continuity with current macro-trends, rather than as isolates whose usefulness and sustainability begins and ends within the museum's precinct. This dissertation begins this proposed shift in point of view by addressing emergent museum practices such as the drafting of digital strategies; the creation of digital reproductions of artworks for online display; and crowdsourcing in the context of theoretical frameworks such as the utopian imagination; ontology of digital-beings; and contemporary labour practices. While not comprehensive, and exploratory in nature, this dissertation contributes to the discipline by providing a new, more in-depth point of view on 'hot' practices, encouraging a contextualisation of the museum that goes beyond the museum itself, into a theoretical and interdisciplinary field that takes advantage of ideas developed within digital humanities, labour critique, informatics and cultural studies.

Cette thèse traite des technologies persuasives et plus particulièrement de leur adaptation, pour en optimiser l’efficacité et la pertinence auprès de l’utilisateur. Les technologies persuasives sont des technologies conçues pour modifier le comportement de leurs utilisateurs, sans utilisation de la coercition ni de la tromperie. L’étude de la persuasion technologique se caractérise par un grand nombre de techniques pour altérer le comportement de l’utilisateur, mais des méthodes pour mettrent en oeuvre ces technologies encoreperfectibles.Elles ont pour fondement la persuasion inter-personnelle, étudiée depuis plus de deux millénaires dans le champ de la rhétorique, de la philosophie, et plus récemment de la psychologie. Cette dernière discipline proposent des théories et modèles pour rendre compte et comprendre les processus à l’oeuvre dans le choix d’un comportement. Ces théories nous montrent en particulier que les situations persuasives sont complexes, variées, avec de nombreux facteurs d’influence. C’est pourquoi nous proposons la notion de technologies persuasives adaptatives, des technologies capables d’adapter leurs stratégies de persuasion à l’utilisateur dans son contexte. Pour mettre en oeuvre ces dispositifs, nous proposons dans un premier un modèle du contexte persuasif, c’est-à-dire de l’ensemble des contraintes qui influencent l’adoption d’un comportement cible par un individu et à un instant donnés. Chacune de ces contraintes est à la fois un critère d’adaptation et un levier d’action dans la quête persuasive de la technologie. Pour chacun de ces leviers, nous avons identifié les techniques de persuasion qui permettent de les actionner. Dans un second temps, nous avons caractérisé l’adaptation de la persuasion sur un espace problème autour de cinq axes : la finalité, la cible, les critères et la dynamique de l’adaptation, ainsi que le rôle joué par l’utilisateur dans ce processus. Enfin, nous avons montré l’intérêt de l’adaptation, et des outils précédemment cités, dans la mise en oeuvre d’un dispositif persuasif dédié à la régulation du temps d’usage du smartphone. / This thesis deals with persuasive technologies, and in particular adaptation of the persuasion in order to optimize efficiency and relevance of those technologies. Persuasive technologies are technologies design to change behaviors without using coercion or deception. Numerous techniques to shape user behavior but few and perfectible methods to design these technologies characterized the research domain of persuasive technologies.The background of persuasive technologies is the traditional interpersonal persuasion, studied for over two thousand years in rethoric, philosophy, and more recently psychology. This last discipline offers many theories and models to understand more precisely the process that determine human behaviors. These theories show in particular that persuasive situations are complex, varied, with many influence factors. That is why we propose the notion of adaptive persuasive technologies : technologies able to adapt their persuasive stategies to the user context. To design these products and services, we propose in the first place a model of the persuasive context, that is all the constraints that influence the practice of a targeted behavior by the user at a given time. Each constraint in the persuasive context is at the same time an adaptation criteria and an action lever for the adaptive persuasive technology. For each lever, we identify the persuasive principle that can be used to move it. In a second time, we propose a problem space that characterized the adaptation of the persuasion, thanks to five axis : the purpose, the target, the criteria and the dynamic of the adaptation, and the user role in the adaptation process. Finally, by making and assessing TILT, a persuasive application dedicated to smartphone usage regulation, we show that the adaptation of the persuasion, with the use of the persuasive contexte model and the problem space, benefits to the persuasive efficiency.

This thesis analyzes the interior of the solar car, used by the JU Solar Team, to improve the user experience in terms of user interaction and ergonomics. Following the Design Thinking methodology, it starts with a research phase to understand how the user interacts with the car and the elements required for this interaction during the race. It also studies the dimension of the actual interior and the anthropometric factors, some changes are proposed for a more efficient use of the space. The next phase explores new buttons and configurations for the steering wheel. The use of prototypes and sketches leads the development of the ideas, which are further developed and defined, including the graphical design and the dimensions of the interior. In the findings, the redesign of the steering wheel and interior is shown in several renders with an explanation of the final design decisions, which can be summarized in: A new shape for the steering wheel where most of the buttons have been added with new shapes and colors. The emergency buttons and light indicators have been allocated on a central control panel. The user has access to the buttons without releasing the steering wheel and the dimension of the canapé has been reduced thanks to a more efficient use of the space. As a part of the thesis a full scale model of the steering wheels and a 1:10 scale model of the interior is provided. This thesis solves some of the problems in the actual design of the solar car and explore some of the important factors in user interaction. A human-centered design approach to a project usually driven by the performance of the car and not the user experience. / Denna avhandling omfattar utveckling av interiör för solbilar med inriktning mot att förbättra för användaren. Arbetet avser att appliceras på Ju Solar teams solbil som ska delta för Högskolan i Jönköping i World Solar Challenge 2017. Forskningen i projektet fokuserar på att förstå hur användaren interagerar och samspelar med bilen och de faktiska problem som föraren har att hantera under tävlingen. Studien omfattar också antropometriska mått där förslag på ändringar gjorts för att optimera utrymmet. Utvärdering av idéer har gjorts med hjälp av skisser och prototyper, som inkluderar den grafiska designen Designbesluten kan sammanfattas med följande: • De viktiga knapparna är alla samlade i ratten. • Användning av form och färg samt position för att enkelt kunna skilja mellan knappar och dess funktioner. • Ny form för ratten med en extra grepp-zon i den övre delen. Ny utformning av knappar, former och konfiguration för ratten. • En central manöverpanel med ljusindikatorer för föraren. • Nya dimensioner av interiören för att minska förarhuvens storlek och därmed minska luftmotståndet. Som en del av avhandlingen finns en fullskalemodell av ratten och en modell i skala 1:10 av interiören tillhandahålls. Solbilar utvecklas vanligen med prestanda som prioritet men denna avhandling utforskar de problemområden som finns i anslutning till solbilens förarmiljö med människan i centrum.

Context-awareness in pervasive computing environments can reduce user interactions with computing devices by making applications adaptive and autonomous. Context-aware applications rely on information about user context and user preferences to guide their own behaviour. However, context-aware applications do not always behave as users expect due to imperfection of context information, incorrect user preferences or incorrect adaptation rules. This may cause users to feel loss of control over their applications. To mitigate these problems, context-aware systems must provide mechanisms to strike a suitable balance between user control and software autonomy. Allowing users to scrutinise the system and allowing the system to sometimes include users in the adaptation decision making, can provide a balance of user control. This thesis addresses the shortcoming in development of context-aware pervasive systems with regard to providing balance between user control and software autonomy. The thesis shows that rather than making a context-aware application a complete black box, it is possible to allow user control of application adaptations. The system can reveal to the user what context information the system uses and how it arrives at adaptation decisions if the user requests such information. The user may decide to alter the adaptive behaviour of the system to achieve desired outcomes. Hence, a context-aware application becomes a closed loop system where the user is put into the loop if requested. The proposed approach is developed under an assumption that users differ in the level of their technology expertise and therefore the system has to provide explanations that are suitable for a particular level of user expertise. The thesis makes two important research contributions: design of the architectural framework and development of the platform exposing autonomic behaviour of context-aware applications. The architectural framework supports developers of context aware-applications in providing balance of control between users and software autonomy. The framework describes a set of models that allow revealing the adaptation behaviour of context-aware applications in a way suitable for users with various levels of expertise. The framework consists of: (i) a model for exposing elements that influence the context-aware behaviour, (ii) a generic architecture for providing balance of control, (iii) a user model, and (iv) a context graph based overview of context-aware adaptations. The platform exposing autonomic behaviour of context-aware applications is a proof of concept prototype of a software infrastructure (middleware) providing balance of control. The software infrastructure includes: (i) a Semantic Manager, developed to serve the description of elements required for explanations of the application behaviour; (ii) an extension of the PACE Middleware, to enable the middleware to expose the context information, preferences, adaptation rules and their evaluation traces, respectively. (iii) supporting tools for the application designer to prepare the overview of context-aware adaptations and review the evaluation traces. Finally, this thesis presents a case study that illustrates and evaluates the system supporting balance of control. This evaluation involves the existing application which is developed using the previous version of the PACE middleware. The case study validates the architectural framework and illustrates the process and issues involved in developing context-aware application that are able to expose elements that influence context-aware behaviour.

Decerno is a software consultancy company who designs and builds large software information systems. They are interested in more knowledge and insight in the benefits and limitations of touch-enabled interfaces as a means of incorporating these into their own products. The aim of this study is to find advice on how to design touch-enabled functionality that would work in a company’s main computer system to be used by staff on a daily basis in order to fulfill their work tasks.Comparing a touch interface to a conventional mouse interface exposes differences in use that need to be kept in mind when designing for touch interaction usability. With a simple flick of the mouse you are able to dart your mouse-pointer across the screen on your conventional mouse interface, but a touch interface requires you to both lift and extend your arm in order to point your finger at the far corner of the touch screen. Extensive use of large or monotonous movements might cause muscle fatigue, which requires you to adapt your interface design to allow for effective touch-interaction use.The main research question in this study has been to derive guidelines and advice on how to present a set of dynamic information making it possible for the user to effectively find and select a specific target by touch interaction. For this purpose a set of sub questions were identified and a test interface was produced in order to evaluate the users touch interaction and their feedback. The results from these user tests have formed the foundation of the concluding guidelines.This has been evaluated both quantitatively and qualitatively in a user study. Measurements was taken on how the users performed, such as number of errors and time to finish the user task. The users were also asked to perform a think-aloud evaluation which collected information on how they used the interface and their thoughts and reactions while doing it. The user tests were concluded with open-ended questions in which the users were asked to reflect on their actions, how user-effective the interface was and to compare different test setups.The results conclude that most users does not like horizontal scrolling. The horizontal movement make the text much harder to follow. Habit also seems to be an important factor as several users expressed the fact that they are much more used to scrolling vertically.Most users preferred the display with both images and text as it made the page more interesting and pleasant to look at, this is in contrast with the fact that most users stated that locating an item is faster and easier without images and only minimal text information, limited to only the search task answer. The aesthetical features of an interface seem to be equally important as the functionality.Another important conclusion is the difference in hand-position when the tablet is placed on the table compared to when it is hand-held. When designing a touch interface, some consideration should be taken to how the user might be working with the interface. The button placement might need to be different depending on if they are likely to be holding the tablet while using it (perhaps in a more informal setting, standing up or moving around) or will they be using it while it is placed on the table.