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Controlling Scalability in Distributed Virtual EnvironmentsSingh, Hermanpreet 01 May 2013 (has links)
A Distributed Virtual Environment (DVE) system provides a shared virtual environment where physically separated users can interact and collaborate over a computer network. More simultaneous DVE users could result in intolerable system performance degradation. We address the three major challenges to improve DVE scalability: effective DVE system performance measurement, understanding the controlling factors of system performance/quality and determining the consequences of DVE system changes.
We propose a DVE Scalability Engineering (DSE) process that addresses these three major challenges for DVE design. DSE allow us to identify, evaluate, and leverage trade-offs among DVE resources, the DVE software, and the virtual environment. DSE has three stages. First, we show how to simulate different numbers and types of users on DVE resources. Collected user study data is used to identify representative user types. Second, we describe a modeling method to discover the major trade-offs between quality of service and DVE resource usage. The method makes use of a new instrumentation tool called ppt. ppt collects atomic blocks of developer-selected instrumentation at high rates and saves it for offline analysis. Finally, we integrate our load simulation and modeling method into a single process to explore the effects of changes in DVE resources.
We use the simple Asteroids DVE as a minimal case study to describe the DSE process. The larger and commercial Torque and Quake III DVE systems provide realistic case studies and demonstrate DSE usage. The Torque case study shows the impact of many users on a DVE system. We apply the DSE process to significantly enhance the Quality of Experience given the available DVE resources. The Quake III case study shows how to identify the DVE network needs and evaluate network characteristics when using a mobile phone platform. We analyze the trade-offs between power consumption and quality of service.
The case studies demonstrate the applicability of DSE for discovering and leveraging tradeoffs between Quality of Experience and DVE resource usage. Each of the three stages can be used individually to improve DVE performance. The DSE process enables fast and effective DVE performance improvement. / Ph. D.
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Human Perception of Aural and Visual Disparity in Virtual EnvironmentsWiker, Erik Daniel 13 September 2018 (has links)
With the development of technology over the past decade and the former challenges of virtual environments mitigated, the need for further study of human interaction with these environments has grown apparent. The visual and interaction components for virtual reality applications have been comprehensively studied, but a lack of spatial audio fidelity leaves a need for understanding how well humans can localize aural cues and discern audio-visual disparity in these virtual environments. In order for development of accurate and efficient levels of audio fidelity, a human study was conducted with 18 participants to see how far a bimodal audio and visual cue need to separate for someone to notice. As suspected, having a visual component paired with an auditory one led to biasing toward the visual component. The average participant noticed a disparity when the audio component was 33.7° apart from the visual one, pertaining to the azimuth. There was no significant evidence to suggest that speed or direction of audio component disparity led to better localization performance by participant. Presence and prior experience did not have an effect on localization performance; however, a larger participant base may be needed to draw further conclusions. Increase in localization ability was observed within a few practice rounds for participants. Overall, performance in virtual reality was parallel to augmented reality performance when a visual source biased sound localization, and can this be a both tool and design constraint for virtual environment developers. / Master of Science / Virtual Reality has overcame a large technological gap over the past decade, allowing itself to be a strong tool in many applications from training to entertainment. The need for studying audio fidelity in virtual environments has emerged from a gap of research in the virtual reality domain. Therefore, a human participant study was conducted to see how well they could localize sound in a virtual environment. This involved signaling when they noticed a visual object and a sound split. The average of 72 trials with 18 participants was 33.7° of separation on the horizontal plane. This can be both a tool and a design constraint for virtual reality developers, who can use this visual biasing as a guideline for future applications.
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Immersive Space to Think: Immersive Analytics for Sensemaking with Non-Quantitative DatasetsLisle, Lorance Richard 09 February 2023 (has links)
Analysts often work with large complex non-quantitative datasets in order to better understand concepts, themes, and other forms of insight contained within them. As defined by Pirolli and Card, this act of sensemaking is cognitively difficult, and is performed iteratively and repetitively through various stages of understanding. Immersive analytics has purported to assist with this process through putting users in virtual environments that allows them to sift through and explore data in three-dimensional interactive settings. Most previous research, however, has focused on quantitative data, where users are interacting with mostly numerical representations of data. We designed Immersive Space to Think, an immersive analytics approach to assist users perform the act of sensemaking with non-quantitative datasets, affording analysts the ability to manipulate data artifacts, annotate them, search through them, and present their findings. We performed several studies to understand and refine our approach and how it affects users sensemaking strategies. An exploratory virtual reality study found that users place documents in 2.5-dimensional structures, where we saw semicircular, environmental, and planar layouts. The environmental layout, in particular, used features of the environment as scaffolding for users' sensemaking process. In a study comparing levels of mixed reality as defined by Milgram-Kishino's Reality-Virtuality Continuum, we found that an augmented virtuality solution best fits users' preferences while still supporting external tools. Lastly, we explored how users deal with varying amounts of space and three-dimensional user interaction techniques in a comparative study comparing small virtual monitors, large virtual monitors, and a seated-version implementation of Immersive Space to Think. Our participants found IST best supported the task of sensemaking, with evidence that users leveraged spatial memory and utilized depth to denote additional meaning in the immersive condition. Overall, Immersive Space to Think affords an effective sensemaking three-dimensional space using 3D user interaction techniques that can leverage embodied cognition and spatial memory which aids the users understanding. / Doctor of Philosophy / Humans are constantly trying to make sense of the world around them. Whether they're a detective trying to understand what happened at a crime scene or a shopper trying to find the best office chair, people are consuming vast quantities of data to assist them with their choices. This process can be difficult, and people are often returning to various pieces of data repeatedly to remember why they are making the choice they decided upon. With the advent of cheap virtual reality products, researchers have pursued the technology as a way for people to better understand large sets of data. However, most mixed reality applications looking into this problem focus on numerical data, whereas a lot of the data people process is multimedia or text-based in nature. We designed and developed a mixed reality approach for analyzing this type of data called Immersive Space to Think. Our approach allows users to look at and move various documents around in a virtual environment, take notes or highlight those documents, search those documents, and create reports that summarize what they've learned. We also performed several studies to investigate and evolve our design. First, we ran a study in virtual reality to understand how users interact with documents using Immersive Space to Think. We found users arranging documents around themselves in a semicircular or flat plane pattern, or using various cues in the virtual environment as a way to organize the document set. Furthermore, we performed a study to understand user preferences with augmented and virtual reality. We found a mix of the two, also known as augmented virtuality, would best support user preferences and ability. Lastly, we ran two comparative studies to understand how three dimensional space and interaction affects user strategies. We ran a small user study looking at how a single student uses a desktop computer with a single display as well as immersive space to think to write essays. We found that they wrote essays with a better understanding of the source data with Immersive Space to Think than the desktop setup. We conducted a larger study where we compared a small virtual monitor simulating a traditional desktop screen, a large virtual monitor simulating a monitor 8 times the size of traditional desktop monitors, and immersive space to think. We found participants engaged with documents more in Immersive Space to Think, and used the space to denote importance for documents. Overall, Immersive Space to Think provides a compelling environment that assists users in understanding sets of documents.
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The Effect of Varied Learning Environments and Modalities on Anatomical Knowledge Acquisition, Perceived Workload, Cybersickness, and Learner Engagement / ANATOMY EDUCATION AND VIRTUAL REALITYHasan, Farah Zareen January 2024 (has links)
Institutions are looking to find the best learning technologies to deliver anatomy curricula to diverse student populations, often working with financial and time-based constraints. Visualization techniques, particularly the widespread use of virtual reality headsets, have made once-impossible learning experiences possible. This thesis explores the effect of different learning modalities (virtual reality headset, computer screen, and 3D-printed models) and environments (clinical context or context-free) on knowledge acquisition and learning experiences for a pelvic floor anatomy module. We investigated how these factors, along with mental rotation ability and stereoacuity, impact various aspects of learning, including performance on anatomy tests, perceived workload (measured using the NASA Task Load Index), cybersickness (measured using the Simulator Sickness Questionnaire), and engagement during learning (measured using the User Engagement Scale). Significant interactions were found between modality and environment for test scores and workload, a significant main effect of modality and environment for cybersickness, and a significant main effect of modality for engagement. Importantly, though significant differences were found between modalities and environments, participants reported concerningly high levels of workload and cybersickness across all conditions. High levels of engagement were also reported across all learning conditions. The lack of meaningful differences between intervention groups emphasizes the importance of curricular design over the implementation of new technologies and the need to be critical of the impression that a one-size-fits-all solution exists. Theories of cognitive load, constructivism, syncretion, visuospatial ability, cybersickness, and embodied learning in the context of technology-enhanced anatomy education are discussed as the foundation upon which design decisions should be made. A multi-faceted approach focused on aligning learning objectives with learning activities is outlined as a means of driving more impactful research and improving anatomy education. / Thesis / Master of Science (MSc) / Institutions are looking to find the best learning technologies to deliver anatomy curricula to diverse student populations, often working with financial and time-based constraints. Visualization techniques have been at the forefront of this innovation, and the widespread use of virtual reality headsets has made once-impossible learning experiences achievable. This thesis explores the effect of different learning modalities and environments on learning with a pelvic floor anatomy module. We investigated how these factors, along with mental rotation ability and stereoacuity impact test performance and the perception of workload, cybersickness, and engagement. The results emphasize the importance of curricular design over the implementation of new technologies and the need to be critical of the impression that a one-size-fits-all solution exists.
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Improving Conveyor Belt Safety Training Through the Use of Virtual RealityLucas, Jason David 30 January 2009 (has links)
Working around conveyor belts is the cause of numerous accidents each year that are costly to the mining industry. Current safety training practices generally include the use of slide show presentations, lectures, videos, and paper material before sending each worker onto site with an experienced person for on-the-job task training. These training methods are passive in nature and do not allow for an actual realization of consequences resulting from ignoring safety practices during interaction between the employee and the environment. It is with this in mind that virtual reality (VR) is being proposed as an added effective method of safety training.
In order to prove this hypothesis, a working VR prototype application of a mining environment has been developed. The application is designed in two modules. The first consists of an instructional based module, where the user is given all relevant information based on background research dealing with safety issues, hazard awareness, conveyor maintenance, and conveyor components and assemblies. The second module is a task-based training session that then tracks the user's performance as they complete assigned tasks.
An evaluation scheme was performed on the prototype to determine the usability and usefulness and identify areas in need of improvement. First, industry professionals were presented the application in an informal setting where the types of information and overall concept were examined and perceived usefulness was discussed. Secondly, users, both novice and industry professionals, were asked to go through the prototype training application and rate their agreement with statements based on the user interface and usability of the application. Finally, subjective interviews were performed to record perceived benefits of the virtual reality application over typical training material. This final stage consists of using both industry professionals and novice experience individuals and documenting their perceptions of benefits and challenges of using both typical methods of training and the designed prototype.
This document consists of an explanation of the research steps and papers that are published (or in press) detailing certain areas of the research, compiled findings, conclusions, and future research suggestions. / Master of Science
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Lessons Learned Over a Growing Development Cycle in Medical SimulationPacheco-San Martin, Alex 01 August 2024 (has links) (PDF)
For the last five years, East Tennessee State University’s Department of Digital Media has partnered with the East Tennessee Children’s Hospital in downtown Knoxville to create a collection of training modules for their nursing staff. Dozens of students have devoted thousands of hours both inside and outside of the department’s various production courses to build the eleven modules currently in use today. However, development has not been without its hurdles, particularly in moving from one project to the next. Poor documentation and miscommunications compounded with faults in the projects’ design philosophies to repeatedly delay production. While each deliverable was playable by the end of the given semesters, there were often bugs and other quality issues left unaddressed. Luckily, graduate assistants and interns were brought on to help direct students in class, and to finish the projects on off-semesters. As one of those graduate assistants, I’ve had the pleasure of working alongside Stephanie Nicely, our project manager and hospital liaison to build on the works of past developers, assist in managing the development of current projects, and lay groundwork for future growth.
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The effect of viewing conditions on visual stress, sickness, and distance estimation in a helmet-mounted displayEhrlich, Jennifer 01 January 1999 (has links)
No description available.
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The effect of restricted field of view on locomotion tasks, head movements, and motion sicknessAllen, Robert Canning 01 October 2000 (has links)
No description available.
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Assessing the readaptation process associated with virtual environment post-exposureReeves, Leah M. 01 January 1999 (has links)
No description available.
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Effects of low stereo acuity on performance presence, and sickness within a virtual environmnetKingdon, Kelly S. 01 July 2001 (has links)
No description available.
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