Most Virtual Reality systems employ some form of parallel processing, making use of multiple processors which are often distributed over large areas geographically, and which communicate via various forms of message passing. The approaches to parallel decomposition differ for each system, as do the performance implications of each approach. Previous comparisons have only identified and categorized the different approaches. None have examined the performance issues involved in the different parallel decompositions. Performance measurement for a Virtual Reality system differs from that of other parallel systems in that some measure of the delays involved with the interaction of the separate components is required, in addition to the measure of the throughput of the system. Existing performance analysis approaches are typically not well suited to providing both these measures. This thesis describes the development of a performance analysis technique that is able to provide measures of both interaction latency and cycle time for a model of a Virtual Reality system. This technique allows performance measures to be generated as symbolic expressions describing the relationships between the delays in the model. It automatically generates constraint regions, specifying the values of the system parameters for which performance characteristics change. The performance analysis technique shows strong agreement with values measured from implementation of three common decomposition strategies on two message passing architectures. The technique is successfully applied to a range of parallel decomposition strategies found in Parallel and Distributed Virtual Reality systems. For each system, the primary decomposition techniques are isolated and analysed to determine their performance characteristics. This analysis allows a comparison of the various decomposition techniques, and in many cases reveals trends in their behaviour that would have gone unnoticed with alternative analysis techniques. The work described in this thesis supports the Performance Analysis and Comparison of Parallel and Distributed Virtual Reality systems. In addition it acts as a reference, describing the performance characteristics of decomposition strategies used in Virtual Reality systems.

Virtual Reality is currently an affordable and consumer ready technology used by many in the games and interactive media industry, however unlike the user interface standards in mobile, PCs, and Macs, VR UI design can vary in complexity and usability. VR has many times been linked in films, TV shows, and animation as a method for navigating through cyberspace. It has been portrayed to be involved in the process of hacking a computer on some network. This study will look at approaches to developing a UI system using cyber-security research applications as a basis for designing a framework. Throughout, this research will analyze the different approaches to UI design and data visualization, extract relevant information, and find out what approaches will help improve the VR software front end design.

Indiana University-Purdue University Indianapolis (IUPUI) / Introduction: Anxiety is a debilitating and difficult sensation many people face on a daily basis. Up to 20% of American adults experience dental anxiety2. Dental anxiety can present both psychologically and physiologically as a barrier to starting, completing and/or finishing dental treatment.2,4 Catastrophizing the procedure, which is common practice in anxious patients, will alter and increase the perception of pain66. Approaching and understanding dental anxiety has shown to produce more positive treatment outcomes and overall increased patient satisfaction2, 4, 6. Non-pharmacological approaches to reducing dental anxiety can be a quick, non-invasive, method to put patients at ease and can save chair time for both practitioner and patient, as well as a more pleasant experience for the patient. Objectives: The goal of this study is to investigate non-pharmacologic approaches to reducing dental anxiety prior to non-surgical root canal treatment. This will be done by comparing an Auditory Alone Brief Relaxation period (ABR) to a Relaxation Virtual Reality period (RVR). Materials and Methods: 60 subjects who need non-surgical root canal treatment was randomly allocated into 2 groups. One group received earphones to listen to a guided brief relaxation recording, focusing on breathing and a body scan. The other group received virtual reality goggles and choose a scene of their liking to experience. State Trait Anxiety Indicator (STAI), Visual Analog Scale (VAS), and vitals were measured to objectively determine baseline anxiety score followed by the same metrics after brief relaxation or virtual reality experience. A student will perform root canal treatment, and VAS and vitals were again be recorded at the end of the appointment. Results: Both RVR and ABR showed a statistically significant decrease in anxiety in STAI-S (p value <.001 for both), STAI-T (p value 0.025 ABR; <.001 RVR). VAS scores also significantly reduced from T1 to T2 to T3 time frame. Discussion: Our study investigated and compared two different interventions in reducing anxiety prior to endodontic therapy. The results showed that both ABR and RVR reduced anxiety prior to endodontic therapy and had an effect even after the endodontic therapy was completed. Additionally, when comparing the time points T1, T2, and T3, heart rate decreased throughout the procedure and more importantly, after the intervention (ABR or RVR) was delivered. Both anxiety scales, STAI and VAS showed a statistical significant decrease in anxiety throughout the appointment. Conclusion: Non-pharmacological techniques like guided meditation and virtual reality are a valid and unique approach to reducing anxiety prior to endodontic therapy. Both ABR and RVR interventions reduced the feelings of anxiety throughout the entire endodontic appointment. This study displays the ease of incorporating both interventions to reduce anxiety in an economical and noninvasive fashion.

Note:

Due to the increased popularity of virtual environment (VE) technology and its potential to develop further technological advances in many fields, considerable research is being done in this area. Nevertheless, VE technology, due to its very nature, depends very strongly on its human user. One of the biggest drawbacks of VE technology today is the health and safety concerns it presents to users. Many VE users experience motion sickness and other aftereffects. In addition, the human body reacts to-these disturbances by adapting to the VE, returning an individual that has learned maladaptive behavior. This is a big concern due to potential health and safety risks. Thus, there is potential to develop effective. measurement techniques that measure changes in visuomotor functioning, such as the kinesthetic position sense (i.e., eye-hand coordination), to gauge VE aftereffects. This research project consists of identifying and testing an objective measurement algorithm that may determine changes in eye-hand coordination by evaluating an individual's pointing ability before and after VE exposure. In order to obtain an effective measurement technique, methods that have proven to quantitatively characterize the nature of pointing behavior and, therefore, provide a measure of kinesthetic position sense, as well as other proposed methods, were investigated. These methods included pointing accuracy in the X, Y and Z directions, difference between identity and experimental touch, the total distance, and the average pointing error. Data gathered from an experiment was analyzed in order to obtain a measurement technique that demonstrates reliability and sensitivity . The results from this study suggested that when measuring changes in proprioceptive functioning due to VE exposure, an individual's exact coordinate location in X, Y and Z dimensions with eyes open conditions (visual feedback) should be measured since, compared to other measurement techniques, this method provides more reliability and sensitivity to changes in proprioceptive functioning.

This study focused on three different menu designs each with their own unique interactions and organizational structures to determine which design features would perform the best. Fifty-four participants completed 27 tasks using each of the three designs. The menus were analyzed based on task performance, accuracy, usability, intuitiveness, and user preference. Also, an analysis was conducted between two different menu organization styles: top-down menu organization (Method-TD) and bottom-up organization (Method-BU). There was no evidence that demographic factors had any effect on the overall results. By and large, the Stacked menu design received very positive results and feedback from all the participants. The Spatial design received average feedback with some participants preferring it while others struggled to use it and felt that it was too physically demanding. The worst performer was the Radial design that consistently ranked last and failed to pass usability and accuracy tests. A NGOMSL study was conducted to determine any differences in performance between a top-down menu organizational approach and a bottom-up approach or differences between the predicted task completion times and the reported times. The results of this study predicted that the Spatial design should have taken the least amount of time to perform, however, the experimental results showed that the Stacked design in fact out-performed the Spatial design’s task completion times. A potential explanation as to why the Stacked outperformed the Spatial is the increased physical demand of the Spatial design not anticipated with the NGOMSL analysis because of a design feature which caused a high level of cumbersomeness with the interactions. Overall, there were no statistical differences found between Method-TD and Method-BU, but a large difference found between the predicted times and observed times for Stacked, Radial, and Spatial. Participants overwhelmingly performed better than the predicted completion times for the Stacked design, but then did not complete the tasks by the predicted times for the Radial and Spatial. This study recommends the Stacked menu for VR environments and proposes further research into a Stacked-Spatial hybrid design to allow for the participant’s preferred design aspects of both designs to be used in a VR environment.

No / The article surveys virtual humans and techniques to control the face and body. It also covers higher level interfaces for direct speech input and issues of real-time control.

Virtual Reality has once again emerged as a platform with great potential for exploratory research. An expectation for the next generation virtual reality platforms is to be used as a tool for graphical designers as a new way to access the virtual world and interact with digital content. Just as mobile applications are developed for smaller screens with touch capabilities and desktop applications for computer screens with the input of mouse and keyboard, the interfaces of VR applications need to be designed with the capabilities and limitations of the platform in mind. A common component in modern graphic editing software is layer management: having the final output of the application divided into sub-components. This thesis explores how layer management can best be implemented in room-scale Virtual Reality with a focus on selection, navigation and manipulation through an iterative design study. The study concludes that, to improve the learnability of a system, interactions should be based on real-world interaction for naturalistic tasks while drawing inspiration from desktop applications for more abstract tasks. Furthermore, the environment needs to be adjusted to the systems designated tasks as well as the physical characteristics of the user. Lastly, as previous studies have suggested, amplifying the movement of manipulated objects in relation to the movement of the controller decreases the required movement of the user, reducing fatigue and increasing the user’s reach. However, this amplification was perceived as a reduction in precision, which some users valued more than movement reduction. Therefore, the amplification factor should be adjusted in relation to the operation’s precision requirements. While directly applicable to layer management in VR, these findings could serve as guidelines for applications utilizing 2D content in a virtual environment, room-scale VR applications designed to perform abstract tasks, and productivity tools for Virtual Reality. / Virtual Reality (VR) har på senare år sett ett uppsving både vad gäller teknisk utveckling och intresse hos konsumenter. Den nya generationens VR-plattformar har stor potential för utforskande studier både vad gäller användningsområden och interaktionsgränssnitt. En av förväntningarna är att VR ska kunna användas inom grafisk formgivning som ett verktyg för att tillgå- och interagera med digitalt innehåll på nya sätt. Precis som mobila applikationer är utvecklade för mindre touch-skärmar och PC-applikationer är designade för mus- och tangentbordsinteraktion med återkoppling genom en datorskärm så kommer gränssnitten för framtidens VR applikationer att vara utformade efter denna plattforms specifikationer. En vanlig komponent i dagens grafiska redigeringsprogramvaror är bildlagerhantering; att ha en bild eller bildruta uppdelad i mindre delar där varje del kan redigeras och påverkas som en separat enhet. Denna uppsats utforskar genom en iterativ designstudie hur bildlagerhantering kan implementeras i en VR miljö med fokus på navigation, val av objekt och manipulation av objekt. Studien visar att interaktionsgränssnitten som baseras på interaktioner med verkligheten och interaktion med traditionella PC applikationer för naturliga respektive abstrakta operationer gör interaktionerna lättare att lära sig och förstå. Förutom de uppgifter som systemet är ämnat att utföra bör även utformningen av den virtuella miljön ta hänsyn till de fysiska egenskaperna hos användaren. Som tidigare studier har visat så kan ett förstärkt utslag av manipulerade objekt i förhållande till kontrollen minska den rörelse som krävs av användaren för att utföra en uppgift och därigenom minska trötthet och öka användarens effektiva räckvidd. Denna förstärkning uppfattades dock som en reducering av precision, vilket vissa användare värdesatte mer än reducering av krävd rörelse. Därför ska förstärkningsgraden sättas i relation till den precision som krävs av varje operation. Studiens resultat är direkt applicerbara för lagerhantering i VR men kan också användas som riktlinjer för VR applikationer som hanterar 2D-innehåll i en 3D miljö samt VR applikationer med syfte att användas som produktivitetsverktyg.

Brummett’s ontological view of epistemic rhetoric frames a world in which reality is truly only shaped once it is communicated. This reality creation is uniquely performed within online spaces that are separated from the physical world by means of programming code and internal culture. These spaces are constructed of language and constitute new realities (Chesebro ) which are fundamentally rhetorical. However, the study of these tools lack shared terminology with which to classify and understand their potential as educational spaces. This study explores connections between communication mechanics of multi-user social technologies and their effectiveness as teaching tools. The study focuses on virtual worlds (defined as WAN-based, persistent, multi-user spaces which include avatars), such as Second Life and World of Warcraft, as examples of multi-user social technologies because these tools converge mechanics and communication tools found separately elsewhere. Communication mechanics are operationalized as facets found through the application of Shiyali Ranganathan’s Faceted Classification method. The facets of seventy worlds are first identified. These facets are then used to describe typical uses of the facets through Activity Theory (Engeström) and Genre Ecology Models (Spinuzzi). Finally, a framework is suggested for selecting virtual worlds and the most effective activities within them by ensuring coordination among the strategic, tactical, and operational goals and activities of the tool, the course/instructor, and student. / Incommensurate terms, incommensurate practices -- Background and current state of virtual world technology -- Classification of virtual worlds -- Using activity theory and genre ecology models to connect facets with motivations in virtual world education -- Implications, limitations and further study. / Department of English

Thesis (M. Arch.)--University of Washington, 1996. / Includes bibliographical references (leaves [47]-50). Issued also electronically via World Wide Web.