1,720,977 research outputs found
Pedestrian Navigation with Degraded GPS Signal: Investigating the Effects of Visualizing Position Uncertainty
No full textNavigation in 3D Virtual Environments: Effects of User Experience and Location-pointing Navigation Aids
No full textIn this paper, we describe the results of an experimental study whose objective was twofold: (1) comparing three navigation aids that help users perform wayfinding tasks in desktop virtual environments (VEs) by pointing out the location of objects or places; (2) evaluating the effects of user experience with 3D desktop VEs on their effectiveness with the considered navigation aids. In particular, we compared navigation performance (in terms of total time to complete an informed search task) of 48 users divided into two groups: subjects in one group had experience in navigating 3D VEs while subjects in the other group did not. The experiment comprised four conditions that differed for the navigation aid that was employed. The first and the second condition, respectively, exploited 3D and 2D arrows to point towards objects that users had to reach; in the third condition, a radar metaphor was employed to show the location of objects in the VE; the fourth condition was a control condition with no location-pointing navigation aid available. The search task was performed both in a VE representing an outdoor geographic area and in an abstract VE that did not resemble any familiar environment. For each VE, users were also asked to order the four conditions according to their preference. Results show that the navigation aid based on 3D arrows outperformed (both in terms of user performance and user preference) the others, except in the case when it was used by experienced users in the geographic VE. In that case, it was as effective as the others. Finally, in the geographic VE, experienced users took significantly less time than inexperienced users to perform the informed search, while in the abstract VE the difference was significant only in the control and the radar conditions. From a more general perspective, our study highlights the need to take into specific consideration user experience in navigating VEs when designing navigation aids and evaluating their effectiveness. © 2007 Elsevier Ltd. All rights reserved
Passive and active navigation of virtual environments vs. traditional printed evacuation maps: A comparative evaluation in the aviation domain
Full text linkPrinted maps are the most common tool to prepare people for emergency evacuation in contexts such as public buildings or transportation. Unfortunately, they are poorly understood and often ignored by people. Virtual environments (VEs) could be a more effective method to support people in acquiring spatial knowledge about the real-world environment to evacuate. This paper pursues three main goals. First, we propose a VE-based tool to support spatial knowledge acquisition for evacuation purposes, using aviation as a real-world domain in which such knowledge is crucial for passengers' safety. Second, we study in detail one of the VE design choices (active or passive navigation), comparing a version of our tool in which users navigate by actively controlling their position with another version in which users are passively led along pre-defined routes. Third, we contrast the two versions of the tool with the traditional, printed diagrammatic map provided to passengers by airlines. Results of our study show that the VE-based approach produces objectively better spatial knowledge when users are asked to pinpoint their assigned position in the environment, and that active navigation produces a performance improvement in a subsequent virtual evacuation. Moreover, the VE-based approach is perceived as more enjoyable, easier to comprehend and more effective than printed maps when active navigation is available
Augmenting Audio Messages with Visual Directions in Mobile Guides: an Evaluation of Three Approaches
No full textSupporting users’ navigation is a fundamental feature of mobile
guides. This paper presents an experimental evaluation
comparing three different ways of providing navigation guidance
by combining visual and audio directions during guided
city tours. The three considered solutions differ in the way
audio directions are augmented with visual directions: a
traditional map-based solution, a combination of a map and
photographs of the area, a combination of large arrows and
photographs. The results of our evaluation show that when
the map is combined with photographs that clearly indicate
the direction to the user or when the map is replaced by a
combination of directional arrows and photographs, users’
performance is significantly better. Moreover, the combination
of map and photographs was highly preferred by users
Interactive visual analysis of geographic data on mobile devices based on dynamic queries
No full textThe capabilities of current mobile devices, especially PDAs, are making it possible to design and
develop mobile applications that employ visual techniques for using geographic data in the field.
These applications can be extremely useful in areas as diverse as tourism, business, natural resources
management and homeland security. In this paper, we present a system aimed at supporting users in
the exploratory analysis of geographic data on PDAs through a highly interactive interface based on
visual dynamic queries. We propose alternative visualizations to display query results and present an
experimental evaluation aimed at comparing their effectiveness on a PDA in a tourist scenario. Our
findings provide an experimental confirmation of the unsuitability of the typical visualization,
employed by classic dynamic query systems, which displays only those results that fully satisfy a
query, in those cases where only sub-optimal results are obtainable. For such cases, the results of our
study highlight the usefulness of visualizations that display all results and their degree of satisfaction
of the query
Mobrex: Visualizing Users' Mobile Browsing Behaviors
No full textThis paper deals with the Mobile Browsing Explorer (Mobrex) to give analysts a set of interactive visualizations that highlight various aspects of how users browse an information space. Here, we describe the tool and demonstrate its support of a user study of three browsing techniques for mobile maps. Although we mainly focus here on PDAs and mobile map browsing, Mobrex can easily support analysts studying user interaction with other information spaces and other devices, including mobile phones and desktop computers
Visualizing References to Off-Screen Content on Mobile Devices: a Comparison of Arrows, Wedge, and Overview plus Detail
No full textWhen navigating large information spaces on mobile devices, the small size of the display often causes relevant content to shift off-screen, greatly increasing the difficulty of spatial tasks such as planning routes or finding points of interest on a map. Two possible approaches to mitigate the problem are Contextual Cues, i.e. visualizing abstract shapes in the border region of the view area to function as visual references to off-screen objects of interest, and Overview + Detail, i.e., simultaneously displaying a detail view and a small-scale overview of the information space. In this paper, we compare the effectiveness of two different Contextual Cues techniques, Wedge (Gustafson et al., 2008) and Scaled Arrows (Burigat et al., 2006), and a classical Overview + Detail visualization that highlights the location of objects of interest in the overview. The study involved different spatial tasks and investigated the scalability of the considered visualizations, testing them with two different numbers of off-screen objects. Results were multifaceted. With simple spatial tasks, no differences emerged among the visualizations. With more complex spatial tasks, Wedge had advantages when the task required to order off-screen objects with respect to their distance from the display window, while Overview + Detail was the best solution when users needed to find those off-screen objects that were closest to each other. Finally, we found that even a small increase in the number of off-screen objects negatively affected user performance in terms of accuracy, especially in the case of Scaled Arrows, while it had a negligible effect in terms of task completion time
Designing a mobile persuasive application to encourage reduction of users' exposure to cell phone RF emissions
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