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- Title
- AUGMENTATION IN VISUAL REALITY (AVR).
- Creator
-
Zhang, Yunjun, Hughes, Charles, University of Central Florida
- Abstract / Description
-
Human eyes, as the organs for sensing light and processing visual information, enable us to see the real world. Though invaluable, they give us no way to ``edit'' the received visual stream or to ``switch'' to a different channel. The invention of motion pictures and computer technologies in the last century enables us to add an extra layer of modifications between the real world and our eyes. There are two major approaches to modifications that we consider here, offline...
Show moreHuman eyes, as the organs for sensing light and processing visual information, enable us to see the real world. Though invaluable, they give us no way to ``edit'' the received visual stream or to ``switch'' to a different channel. The invention of motion pictures and computer technologies in the last century enables us to add an extra layer of modifications between the real world and our eyes. There are two major approaches to modifications that we consider here, offline augmentation and online augmentation. The movie industry has pushed offline augmentation to an extreme level; audiences can experience visual surprises that they have never seen in their real lives, even though it may take a few months or years for the production of the special visual effects. On the other hand, online augmentation requires that modifications be performed in real time. This dissertation addresses problems in both offline and online augmentation. The first offline problem addressed here is the generation of plausible video sequences after removing relatively large objects from the original videos. In order to maintain temporal coherence among the frames, a motion layer segmentation method is applied. From this, a set of synthesized layers is generated by applying motion compensation and a region completion algorithm. Finally, a plausibly realistic new video, in which the selected object is removed, is rendered given the synthesized layers and the motion parameters. The second problem we address is to construct a blue screen key for video synthesis or blending for Mixed Reality (MR) applications. As a well researched area, blue screen keying extracts a range of colors, typically in the blue spectrum, from a captured video sequence to enable the compositing of multiple image sources. Under ideal conditions with uniform lighting and background color, a high quality key can be generated through commercial products, even in real time. However, A Mixed Realty application typically involves a head-mounted display (HMD) with poor camera quality. This in turn requires the keying algorithm to be robust in the presence of noise. We conduct a three stage keying algorithm to reduce the noise in the key output. First a standard blue screen keying algorithm is applied to the input to get a noisy key; second the image gradient information and the corresponding region are compared with the result in the first step to remove noise in the blue screen area; and finally a matting approach is applied on the boundary of the key to improve the key quality. Another offline problem we address in this dissertation is the acquisition of correct transformation between the different coordinate frames in a Mixed Reality (MR) application. Typically an MR system includes at least one tracking system. Therefore the 3D coordinate frames that need to be considered include the cameras, the tracker, the tracker system and a world. Accurately deriving the transformation between the head-mounted display camera and the affixed 6-DOF tracker is critical for mixed reality applications. This transformation brings the HMD cameras into the tracking coordinate frame, which in turn overlaps with a virtual coordinate frame to create a plausible mixed visual experience. We carry out a non-linear optimization method to recover the camera-tracker transformation with respect to the image reprojection error. For online applications, we address a problem to extend the luminance range in mixed reality environments. We achieve this by introducing Enhanced Dynamic Range Video, a technique based on differing brightness settings for each eye of a video see-through head mounted display (HMD). We first construct a Video-Driven Time-Stamped Ball Cloud (VDTSBC), which serves as a guideline and a means to store temporal color information for stereo image registration. With the assistance of the VDTSBC, we register each pair of stereo images, taking into account confounding issues of occlusion occurring within one eye but not the other. Finally, we apply luminance enhancement on the registered image pairs to generate an Enhanced Dynamic Range Video.
Show less - Date Issued
- 2007
- Identifier
- CFE0001757, ucf:47285
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001757
- Title
- SERIES OF DISINTEGRATED MEMORIES.
- Creator
-
balas, simona, Hall, Scott, University of Central Florida
- Abstract / Description
-
Being absent from things or places for a period of time, we try to connect by revisiting our memories. There is always a vivid remembrance of certain objects or surroundings, but when we try to connect them, the truth in our mind deviates from the reality. The disintegration of the memories and the morphing of our imagination create a different reality in our minds that we begin to believe, considering that the truth becomes almost completely abstracted and obscured as time passes.
- Date Issued
- 2007
- Identifier
- CFE0001655, ucf:47248
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001655
- Title
- THE DEVELOPMENT OF A DISMOUNTED INFANTRY EMBEDDED TRAINER WITH AN INTELLIGENT TUTOR SYSTEM.
- Creator
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Sims, Jason, Kincaid, Peter, University of Central Florida
- Abstract / Description
-
The dismounted infantry system is a man wearable system with intelligent tutoring tool used to assess training. The tasks used to assess training for the intelligent tutoring were: (1) move as a member of a fireteam, (2) enter and clear a room, and (3) report battlefield information. The soldier wearing the simulation system acts as a member of a fireteam to conduct a virtual mission. The soldier's teammates are computer generated entities to conduct the mission. Soldiers were surveyed on the...
Show moreThe dismounted infantry system is a man wearable system with intelligent tutoring tool used to assess training. The tasks used to assess training for the intelligent tutoring were: (1) move as a member of a fireteam, (2) enter and clear a room, and (3) report battlefield information. The soldier wearing the simulation system acts as a member of a fireteam to conduct a virtual mission. The soldier's teammates are computer generated entities to conduct the mission. Soldiers were surveyed on the tasks assessed as well as the features of the system. Soldiers were also surveyed on tasks they felt needed to be added to the tutoring functions of the system. The intelligent tutor system and training in virtual reality was generally accepted by the participants. The general consensus was the technology needed additional refinement to provide a better training environment. Most felt that working with Semi-Automated Forces (SAF) entities made the scenario more difficult to execute. The parameters established for successful completion of the movement and reporting tasks were too strict and hindered the experience for the participant. Locomotion is another aspect that deserves further research. Moving the locomotion controls to the feet would free the soldier from having to accomplish multiple tasks with only two hands. Future research should concentrate on locomotion methods and controls, as well as only using human participants for all unit members.
Show less - Date Issued
- 2006
- Identifier
- CFE0000986, ucf:46717
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000986
- Title
- TRAINING WAYFINDING: NATURAL MOVEMENT IN MIXED REALITY.
- Creator
-
Savage, Ruthann, Gilson, Richard, University of Central Florida
- Abstract / Description
-
The Army needs a distributed training environment that can be accessed whenever and wherever required for training and mission rehearsal. This paper describes an exploratory experiment designed to investigate the effectiveness of a prototype of such a system in training a navigation task. A wearable computer, acoustic tracking system, and see-through head mounted display (HMD) were used to wirelessly track users' head position and orientation while presenting a graphic representation of...
Show moreThe Army needs a distributed training environment that can be accessed whenever and wherever required for training and mission rehearsal. This paper describes an exploratory experiment designed to investigate the effectiveness of a prototype of such a system in training a navigation task. A wearable computer, acoustic tracking system, and see-through head mounted display (HMD) were used to wirelessly track users' head position and orientation while presenting a graphic representation of their virtual surroundings, through which the user walked using natural movement. As previous studies have shown that virtual environments can be used to train navigation, the ability to add natural movement to a type of virtual environment may enhance that training, based on the proprioceptive feedback gained by walking through the environment. Sixty participants were randomly assigned to one of three conditions: route drawing on printed floor plan, rehearsal in the actual facility, and rehearsal in a mixed reality (MR) environment. Participants, divided equally between male and female in each group, studied verbal directions of route, then performed three rehearsals of the route, with those in the map condition drawing it onto three separate printed floor plans, those in the practice condition walking through the actual facility, and participants in the MR condition walking through a three dimensional virtual environment, with landmarks, waypoints and virtual footprints. A scaling factor was used, with each step in the MR environment equal to three steps in the real environment, with the MR environment also broken into "tiles", like pages in an atlas, through which participant progressed, entering each tile in succession until they completed the entire route. Transfer of training testing that consisted of a timed traversal of the route through the actual facility showed a significant difference in route knowledge based on the total time to complete the route, and the number of errors committed while doing so, with "walkers" performing better than participants in the paper map or MR condition, although the effect was weak. Survey knowledge showed little difference among the three rehearsal conditions. Three standardized tests of spatial abilities did not correlate with route traversal time, or errors, or with 3 of the 4 orientation localization tasks. Within the MR rehearsal condition there was a clear performance improvement over the three rehearsal trials as measured by the time required to complete the route in the MR environment which was accepted as an indication that learning occurred. As measured using the Simulator Sickness Questionnaire, there were no incidents of simulator sickness in the MR environment. Rehearsal in the actual facility was the most effective training condition; however, it is often not an acceptable form of rehearsal given an inaccessible or hostile environment. Performance between participants in the other two conditions were indistinguishable, pointing toward continued experimentation that should include the combined effect of paper map rehearsal with mixed reality, especially as it is likely to be the more realistic case for mission rehearsal, since there is no indication that maps should be eliminated. To walk through the environment beforehand can enhance the Soldiers' understanding of their surroundings, as was evident through the comments from participants as they moved from MR to the actual space: "This looks like I was just here", and "There's that pole I kept having trouble with". Such comments lead one to believe that this is a tool to continue to explore and apply. While additional research on the scaling and tiling factors is likely warranted, to determine if the effect can be applied to other environments or tasks, it should be pointed out that this is not a new task for most adults who have interacted with maps, where a scaling factor of 1 to 15,000 is common in orienteering maps, and 1 to 25,000 in military maps. Rehearsal time spent in the MR condition varied widely, some of which could be blamed on an issue referred to as "avatar excursions", a system anomaly that should be addressed in future research. The proprioceptive feedback in MR was expected to positively impact performance scores. It is very likely that proprioceptive feedback is what led to the lack of simulator sickness among these participants. The design of the HMD may have aided in the minimal reported symptoms as it allowed participants some peripheral vision that provided orientation cues as to their body position and movement. Future research might include a direct comparison between this MR, and a virtual environment system through which users move by manipulating an input device such as a mouse or joystick, while physically remaining stationary. The exploration and confirmation of the training capabilities of MR as is an important step in the development and application of the system to the U.S. Army training mission. This experiment was designed to examine one potential training area in a small controlled environment, which can be used as the foundation for experimentation with more complex tasks such as wayfinding through an urban environment, and or in direct comparison to more established virtual environments to determine strengths, as well as areas for improvement, to make MR as an effective addition to the Army training mission.
Show less - Date Issued
- 2006
- Identifier
- CFE0001288, ucf:46917
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001288
- Title
- THE ROLE OF EXPECTATIONS IN THE PERCEIVED USEFULNESS AND ACCEPTANCE OF VIRTUAL REALITY AS A PREVENTATIVE TECHNIQUE FOR POST-TRAUMATIC STRESS DISORDER.
- Creator
-
Kreutzer, Christine, Bowers, Clint, University of Central Florida
- Abstract / Description
-
Expectancy theory is based on the subjective probability (expectancy) and projected value (valence). Based on this notion, an individual chooses his or her behaviors based on the interaction between the valences perceived to be associated with the outcomes, and the appraisal of the probability of that behavior resulting in those outcomes. Expectancies have been found to be predictive of many outcomes, such as treatment outcomes, behavioral change, and training reactions. The goal of the...
Show moreExpectancy theory is based on the subjective probability (expectancy) and projected value (valence). Based on this notion, an individual chooses his or her behaviors based on the interaction between the valences perceived to be associated with the outcomes, and the appraisal of the probability of that behavior resulting in those outcomes. Expectancies have been found to be predictive of many outcomes, such as treatment outcomes, behavioral change, and training reactions. The goal of the present study is to empirically investigate this issue within the mental health field. While virtual reality appears to be a promising preventative technique for post-traumatic stress disorder, the literature has not yet accounted for expectations and their influence on reactions. More specifically, it is unknown how expectancies influence reactions. Therefore, this study examines videogame self-efficacy as a mechanism through which expectations influence reactions. In the present study 60 participants completed an expectancy scale, VGSE scale, played a serious game designed to prepare soldiers for the psychological challenges associated with deployment, and completed a reactions survey. A mediation analysis was conducted to examine if videogame self-efficacy is a mechanism through which expectations predict reactions. Analyses revealed that videogame self-efficacy partially mediated the relationship between expectancies and reactions.
Show less - Date Issued
- 2013
- Identifier
- CFH0004523, ucf:45189
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH0004523
- Title
- EXPLORING ADDITIONAL FACTORS OF PRESENCE.
- Creator
-
Chertoff, Dustin, Goldiez, Brian, University of Central Florida
- Abstract / Description
-
One of the oft cited reasons for virtual environments is that they provide experiences with places one would never be able to visit and to perform tasks that would otherwise be dangerous, or inaccessible. The ability to become transported to another environment, such that you think you are "there," is known as presence. Existing presence literature focuses largely on the sensory aspects of virtual environment experiences. However, there is more to experience than what is sensed. This...
Show moreOne of the oft cited reasons for virtual environments is that they provide experiences with places one would never be able to visit and to perform tasks that would otherwise be dangerous, or inaccessible. The ability to become transported to another environment, such that you think you are "there," is known as presence. Existing presence literature focuses largely on the sensory aspects of virtual environment experiences. However, there is more to experience than what is sensed. This dissertation investigates the theoretical components of holistic experiences in virtual environments. In order to explore the relationship between experiential design and presence, a new evaluation tool was needed. This ultimately led to the development of the Virtual Experience Test. To validate the Virtual Experience Test, an experiment was designed that utilized subjective evaluations regarding game-play in the commercial game Mirror's Edge. Measures of experiential design, flow, and presence were taken and the relationships between the measures analyzed. The results of this research showed that environments utilizing holistic designs result in significantly higher presence. Furthermore, this study produced a validated measure of holistic experience that designers could use to evaluate their virtual environments.
Show less - Date Issued
- 2009
- Identifier
- CFE0002779, ucf:48133
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002779
- Title
- BEHAVIORAL RESPONSE TO ENDOGENOUS RISK IN THE LABORATORY.
- Creator
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Sen, Shabori, Harrison, Glenn, University of Central Florida
- Abstract / Description
-
Risk is endogenous when an individual is able to undertake mitigation or self protection actions that reduce the risk that he faces. Most risky environments studied in economics involve endogenous risk. This dissertation studies the conceptual and behavioral implications of introducing endogeneity in the controlled environment of the laboratory. The dissertation consists of three different experiments designed to examine how endogeneity affects risk attitudes and risk perceptions in simple...
Show moreRisk is endogenous when an individual is able to undertake mitigation or self protection actions that reduce the risk that he faces. Most risky environments studied in economics involve endogenous risk. This dissertation studies the conceptual and behavioral implications of introducing endogeneity in the controlled environment of the laboratory. The dissertation consists of three different experiments designed to examine how endogeneity affects risk attitudes and risk perceptions in simple experimental set ups. All three experiments employ a virtual reality scenario where the subject is able to form his own beliefs, based on naturalistic cues provided by the virtual reality experience. In the first experiment, a ÂÂ"short runÂÂ" individual experiment, subjects experience several forest fires that allow them to form beliefs about the probability of a house in the simulated forest being destroyed by fire. The evidence suggests that endogenous risk settings do cause subjects to employ different subjective beliefs than they use in an exogenous risk setting, although risk attitudes appear stable across these settings. Typically, the risk of natural disaster in any area is very small, and an adverse event like a forest fire occurs only once in a couple of decades. This has implications for self-protection expenditure where risk is endogenous. A ÂÂ"long runÂÂ" individual experiment with several rounds of decision making allows the estimation of subjective beliefs about the risk of the property burning when a fire may occur. This design allows for the study of the effect of an actual experience of forest fire on a subjectÂÂ's beliefs. Several mitigation options are collective in nature and require group contributions for the self-protection action to be provided. In an extension of the long run design, we study the effect of an actual experience of fire on beliefs when the risk is faced by a group rather than an individual. This framework also allows us to compare behavior in a public goods game involving risk, with the standard public goods game.
Show less - Date Issued
- 2010
- Identifier
- CFE0003315, ucf:48485
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003315
- Title
- Mediated Physicality: Inducing Illusory Physicality of Virtual Humans via Their Interactions with Physical Objects.
- Creator
-
Lee, Myungho, Welch, Gregory, Wisniewski, Pamela, Hughes, Charles, Bruder, Gerd, Wiegand, Rudolf, University of Central Florida
- Abstract / Description
-
The term virtual human (VH) generally refers to a human-like entity comprised of computer graphics and/or physical body. In the associated research literature, a VH can be further classified as an avatar(-)a human-controlled VH, or an agent(-)a computer-controlled VH. Because of the resemblance with humans, people naturally distinguish them from non-human objects, and often treat them in ways similar to real humans. Sometimes people develop a sense of co-presence or social presence with the...
Show moreThe term virtual human (VH) generally refers to a human-like entity comprised of computer graphics and/or physical body. In the associated research literature, a VH can be further classified as an avatar(-)a human-controlled VH, or an agent(-)a computer-controlled VH. Because of the resemblance with humans, people naturally distinguish them from non-human objects, and often treat them in ways similar to real humans. Sometimes people develop a sense of co-presence or social presence with the VH(-)a phenomenon that is often exploited for training simulations where the VH assumes the role of a human. Prior research associated with VHs has primarily focused on the realism of various visual traits, e.g., appearance, shape, and gestures. However, our sense of the presence of other humans is also affected by other physical sensations conveyed through nearby space or physical objects. For example, we humans can perceive the presence of other individuals via the sound or tactile sensation of approaching footsteps, or by the presence of complementary or opposing forces when carrying a physical box with another person. In my research, I exploit the fact that these sensations, when correlated with events in the shared space, affect one's feeling of social/co-presence with another person. In this dissertation, I introduce novel methods for utilizing direct and indirect physical-virtual interactions with VHs to increase the sense of social/co-presence with the VHs(-)an approach I refer to as mediated physicality. I present results from controlled user studies, in various virtual environment settings, that support the idea that mediated physicality can increase a user's sense of social/co-presence with the VH, and/or induced realistic social behavior. I discuss relationships to prior research, possible explanations for my findings, and areas for future research.
Show less - Date Issued
- 2019
- Identifier
- CFE0007485, ucf:52687
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007485
- Title
- CONFORMAL TRACKING FOR VIRTUAL ENVIRONMENTS.
- Creator
-
Davis, Jr., Larry Dennis, Rolland, Jannick P., University of Central Florida
- Abstract / Description
-
A virtual environment is a set of surroundings that appears to exist to a user through sensory stimuli provided by a computer. By virtual environment, we mean to include environments supporting the full range from VR to pure reality. A necessity for virtual environments is knowledge of the location of objects in the environment. This is referred to as the tracking problem, which points to the need for accurate and precise tracking in virtual environments.Marker-based tracking is a technique...
Show moreA virtual environment is a set of surroundings that appears to exist to a user through sensory stimuli provided by a computer. By virtual environment, we mean to include environments supporting the full range from VR to pure reality. A necessity for virtual environments is knowledge of the location of objects in the environment. This is referred to as the tracking problem, which points to the need for accurate and precise tracking in virtual environments.Marker-based tracking is a technique which employs fiduciary marks to determine the pose of a tracked object. A collection of markers arranged in a rigid configuration is called a tracking probe. The performance of marker-based tracking systems depends upon the fidelity of the pose estimates provided by tracking probes.The realization that tracking performance is linked to probe performance necessitates investigation into the design of tracking probes for proponents of marker-based tracking. The challenges involved with probe design include prediction of the accuracy and precision of a tracking probe, the creation of arbitrarily-shaped tracking probes, and the assessment of the newly created probes.To address these issues, we present a pioneer framework for designing conformal tracking probes. Conformal in this work means to adapt to the shape of the tracked objects and to the environmental constraints. As part of the framework, the accuracy in position and orientation of a given probe may be predicted given the system noise. The framework is a methodology for designing tracking probes based upon performance goals and environmental constraints. After presenting the conformal tracking framework, the elements used for completing the steps of the framework are discussed. We start with the application of optimization methods for determining the probe geometry. Two overall methods for mapping markers on tracking probes are presented, the Intermediary Algorithm and the Viewpoints Algorithm.Next, we examine the method used for pose estimation and present a mathematical model of error propagation used for predicting probe performance in pose estimation. The model uses a first-order error propagation, perturbing the simulated marker locations with Gaussian noise. The marker locations with error are then traced through the pose estimation process and the effects of the noise are analyzed. Moreover, the effects of changing the probe size or the number of markers are discussed.Finally, the conformal tracking framework is validated experimentally. The assessment methods are divided into simulation and post-fabrication methods. Under simulation, we discuss testing of the performance of each probe design. Then, post-fabrication assessment is performed, including accuracy measurements in orientation and position. The framework is validated with four tracking probes. The first probe is a six-marker planar probe. The predicted accuracy of the probe was 0.06 deg and the measured accuracy was 0.083 plus/minus 0.015 deg. The second probe was a pair of concentric, planar tracking probes mounted together. The smaller probe had a predicted accuracy of 0.206 deg and a measured accuracy of 0.282 plus/minus 0.03 deg. The larger probe had a predicted accuracy of 0.039 deg and a measured accuracy of 0.017 plus/minus 0.02 deg. The third tracking probe was a semi-spherical head tracking probe. The predicted accuracy in orientation and position was 0.54 plus/minus 0.24 deg and 0.24 plus/minus 0.1 mm, respectively. The experimental accuracy in orientation and position was 0.60 plus/minus 0.03 deg and 0.225 plus/minus 0.05 mm, respectively. The last probe was an integrated, head-mounted display probe, created using the conformal design process. The predicted accuracy of this probe was 0.032 plus/minus 0.02 degrees in orientation and 0.14 plus/minus 0.08 mm in position. The measured accuracy of the probe was 0.028 plus/minus 0.01 degrees in orientation and 0.11 plus/minus 0.01 mm in position
Show less - Date Issued
- 2004
- Identifier
- CFE0000058, ucf:52856
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000058
- Title
- ORIENTING OF VISUAL-SPATIAL ATTENTION WITH AUGMENTED REALITY: EFFECTS OF SPATIAL AND NON-SPATIAL MULTI-MODAL CUES.
- Creator
-
Jerome, Christian, Mouloua, Mustapha, University of Central Florida
- Abstract / Description
-
Advances in simulation technology have brought about many improvements to the way we train tasks, as well as how we perform tasks in the operational field. Augmented reality (AR) is an example of how to enhance the user's experience in the real world with computer generated information and graphics. Visual search tasks are known to be capacity demanding and therefore may be improved by training in an AR environment. During the experimental task, participants searched for enemies (while...
Show moreAdvances in simulation technology have brought about many improvements to the way we train tasks, as well as how we perform tasks in the operational field. Augmented reality (AR) is an example of how to enhance the user's experience in the real world with computer generated information and graphics. Visual search tasks are known to be capacity demanding and therefore may be improved by training in an AR environment. During the experimental task, participants searched for enemies (while cued from visual, auditory, tactile, combinations of two, or all three modality cues) and tried to shoot them while avoiding shooting the civilians (fratricide) for two 2-minute low-workload scenarios, and two 2-minute high-workload scenarios. The results showed significant benefits of attentional cuing on visual search task performance as revealed by benefits in reaction time and accuracy from the presence of the haptic cues and auditory cues when displayed alone and the combination of the visual and haptic cues together. Fratricide occurrence was shown to be amplified by the presence of the audio cues. The two levels of workload produced differences within individual's task performance for accuracy and reaction time. Accuracy and reaction time were significantly better with the medium cues than all the others and the control condition during low workload and marginally better during high workload. Cue specificity resulted in a non-linear function in terms of performance in the low workload condition. These results are in support of Posner's (1978) theory that, in general, cueing can benefit locating targets in the environment by aligning the attentional system with the visual input pathways. The cue modality does not have to match the target modality. This research is relevant to potential applications of AR technology. Furthermore, the results identify and describe perceptual and/or cognitive issues with the use of displaying computer generated augmented objects and information overlaid upon the real world. The results also serve as a basis for providing a variety of training and design recommendations to direct attention during military operations. Such recommendations include cueing the Soldier to the location of hazards, and mitigating the effects of stress and workload.
Show less - Date Issued
- 2006
- Identifier
- CFE0001481, ucf:47092
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001481
- Title
- SURVIVING REALITY: SURVIVOR & PARASOCIAL INTERACTION.
- Creator
-
Davila-Rosado, Pedro, Collins, Steven, University of Central Florida
- Abstract / Description
-
Parasocial interaction is the name that Horton & Wohl coined to describe a viewer's attachmentent toward onscreen persona that they had never physically interacted with (1956). A. Rubin, Perse, & Powell (1985) continued the research and created the Parasocial Interaction Scale. The scale has become the standard in gauging parasocial interaction in various forms of media from soap operas to newscasts. The purpose of this study was top examine parasocial interaction and see if the concept could...
Show moreParasocial interaction is the name that Horton & Wohl coined to describe a viewer's attachmentent toward onscreen persona that they had never physically interacted with (1956). A. Rubin, Perse, & Powell (1985) continued the research and created the Parasocial Interaction Scale. The scale has become the standard in gauging parasocial interaction in various forms of media from soap operas to newscasts. The purpose of this study was top examine parasocial interaction and see if the concept could be applied to the current television trend of reality television. Simultaneously, the study also examined parasocial interaction and its possible connections to loneliness, interpersonal functional alternatives, television viewing motives, exposure, gender, age, and spokesperson selection. The data for this study was collected on the Internet website www.Survivorthesis.com. More than 450 respondents attempted the survey, but only 444 were viable due to incomplete data, repetition, and lack of proof of age. The results of the study found that there was a link between parasocial interaction and loneliness, exposure, spokesperson selection, and television viewing motives. There was no correlation found between parasocial interaction and interpersonal functional alternatives, age, gender.
Show less - Date Issued
- 2006
- Identifier
- CFE0001090, ucf:46779
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001090
- Title
- THE EFFECTS OF ALCOHOL BASED CUES: VIRTUAL REALITY VERSUS GUIDED IMAGERY.
- Creator
-
Labriola, Nicole, Cassisi, Jeffrey, University of Central Florida
- Abstract / Description
-
The use of Virtual Reality (VR) and Imagery have been utilized in psychological practices and treatment. VR has recently been the focus of research with treatments for post traumatic stress disorder, substance abuse, and phobias, among other social and behavioral issues. VR allows the researcher to create realistic controlled environments in which they are able to manipulate the experiment. Imagery permits the individual to imagine and recall scenarios from their past in order to create a...
Show moreThe use of Virtual Reality (VR) and Imagery have been utilized in psychological practices and treatment. VR has recently been the focus of research with treatments for post traumatic stress disorder, substance abuse, and phobias, among other social and behavioral issues. VR allows the researcher to create realistic controlled environments in which they are able to manipulate the experiment. Imagery permits the individual to imagine and recall scenarios from their past in order to create a more personal environment. This experiment aimed to expand upon VR practices and treatment in regards to alcohol research. In this experiment, 70 participants, 39 females and 31 males, were exposed to two VR alcohol and two Imagery alcohol cue environments. Subject craving and psychophysiological measures were taken across all four scenes and all baselines. Overall, craving measures demonstrated that female nondrinkers developed higher cravings during Imagery. Conversely, male social drinkers demonstrated higher cravings during VR. This study supports the use of VR environments in the study of alcohol cue reactivity.
Show less - Date Issued
- 2011
- Identifier
- CFH0003813, ucf:44723
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH0003813
- Title
- Odorants, memory, and presence in warfighters: Do the scents of war matter?.
- Creator
-
Munyan, Benson, Neer, Sandra, Beidel, Deborah, Jentsch, Florian, Joseph, Dana, University of Central Florida
- Abstract / Description
-
Background: Exposure therapy (EXP) is a first-line intervention for combat-related PTSD. EXP works by repeatedly exposing the patient to the feared stimuli, situation, or physical sensations in the absence of actual danger until the stimuli no longer evoke maladaptive responses. Over the past decade, multiple technologies have been introduced to augment the EXP process by presenting multi-sensory cues (e.g., sights, smells, sounds) to increase patients' sense of presence. Exploratory research...
Show moreBackground: Exposure therapy (EXP) is a first-line intervention for combat-related PTSD. EXP works by repeatedly exposing the patient to the feared stimuli, situation, or physical sensations in the absence of actual danger until the stimuli no longer evoke maladaptive responses. Over the past decade, multiple technologies have been introduced to augment the EXP process by presenting multi-sensory cues (e.g., sights, smells, sounds) to increase patients' sense of presence. Exploratory research has only broadly examined the effect of odorants on the patient's sense of presence during simulated exposure tasks. This study hypothesized that those with autobiographical memories similar to the virtual environment (VE) and those who received odorants would report experiencing more presence than experimental controls. Methods: 61 veterans and civilian subjects were randomized and asked to participate in a virtual environment simulating a routine OIF/OEF/OND convoy. The effects of odorants and autobiographical memory on presence were assessed via electrodermal activity, respiration, heart rate variability, and self-report measures. Results: Odorants did not significantly influence presence. A relationship between military experience and presence, HRV, and realism was observed. Conclusion: Odorants did not have a statistically significant effect on presence while engaged in a simulated exposure task, which was inconsistent with previous research. The rationale for these findings and recommendations for future research are made.
Show less - Date Issued
- 2018
- Identifier
- CFE0007060, ucf:51999
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007060
- Title
- If a Virtual Tree Falls in a Simulated Forest, is the Sound Restorative? An Examination of the Role of Level of Immersion in the Restorative Capacity of Virtual Nature Environments.
- Creator
-
Michaelis, Jessica, Smither, Janan, Mcconnell, Daniel, Beidel, Deborah, Harris, Paul, University of Central Florida
- Abstract / Description
-
Stress and cognitive fatigue have become a pervasive problem, especially in Western society. Stress and cognitive fatigue can have deleterious effects not only on performance, but also on one's physical and mental health. This dissertation presents a study in which the aim is to investigate the effects of virtual nature on stress reduction and cognitive restoration. Specifically, this study assessed the effects of Immersion (Non-immersive, Semi-immersive, Fully-immersive) and Exploration ...
Show moreStress and cognitive fatigue have become a pervasive problem, especially in Western society. Stress and cognitive fatigue can have deleterious effects not only on performance, but also on one's physical and mental health. This dissertation presents a study in which the aim is to investigate the effects of virtual nature on stress reduction and cognitive restoration. Specifically, this study assessed the effects of Immersion (Non-immersive, Semi-immersive, Fully-immersive) and Exploration (Passive vs Active) on stress reduction and cognitive restoration. Additionally, restoration from the most effective virtual nature environment was compared to that of taking an active coloring break. Eighty-three university students with normal color vision, depth perception and good visual acuity participated in this study. The overall findings of the study suggest that virtual nature is able to reduce stress and anxiety, generally the more immersive and interactive the better. Moreover, though both the those in the passive VR nature condition and those in the coloring condition reported a reduction in stress, only those in the passive VR nature condition exhibited the physiological changes indicative of stress reduction.
Show less - Date Issued
- 2019
- Identifier
- CFE0007687, ucf:52516
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007687
- Title
- AR Physics: Transforming physics diagrammatic representations on paper into interactive simulations.
- Creator
-
Zhou, Yao, Underberg-Goode, Natalie, Lindgren, Robb, Moshell, Jack, Peters, Philip, University of Central Florida
- Abstract / Description
-
A problem representation is a cognitive structure created by the solver in correspondence to the problem. Sketching representative diagrams in the domain of physics encourages a problem solving strategy that starts from 'envisionment' by which one internally simulates the physical events and predicts outcomes. Research studies also show that sketching representative diagrams improves learner's performance in solving physics problems. The pedagogic benefits of sketching representations on...
Show moreA problem representation is a cognitive structure created by the solver in correspondence to the problem. Sketching representative diagrams in the domain of physics encourages a problem solving strategy that starts from 'envisionment' by which one internally simulates the physical events and predicts outcomes. Research studies also show that sketching representative diagrams improves learner's performance in solving physics problems. The pedagogic benefits of sketching representations on paper make this traditional learning strategy remain pivotal and worthwhile to be preserved and integrated into the current digital learning landscape.In this paper, I describe AR Physics, an Augmented Reality based application that intends to facilitate one's learning of physics concepts about objects' linear motion. It affords the verified physics learning strategy of sketching representative diagrams on paper, and explores the capability of Augmented Reality in enhancing visual conceptions. The application converts the diagrams drawn on paper into virtual representations displayed on a tablet screen. As such learners can create physics simulation based on the diagrams and test their (")envisionment(") for the diagrams. Users' interaction with AR Physics consists of three steps: 1) sketching a diagram on paper; 2) capturing the sketch with a tablet camera to generate a virtual duplication of the diagram on the tablet screen, and 3) placing a physics object and configuring relevant parameters through the application interface to construct a physics simulation.A user study about the efficiency and usability of AR Physics was performed with 12 college students. The students interacted with the application, and completed three tasks relevant to the learning material. They were given eight questions afterwards to examine their post-learning outcome. The same questions were also given prior to the use of the application in order to comparewith the post results. System Usability Scale (SUS) was adopted to assess the application's usability and interviews were conducted to collect subjects' opinions about Augmented Reality in general. The results of the study demonstrate that the application can effectively facilitate subjects' understanding the target physics concepts. The overall satisfaction with the application's usability was disclosed by the SUS score. Finally subjects expressed that they gained a clearer idea about Augmented Reality through the use of the application.
Show less - Date Issued
- 2014
- Identifier
- CFE0005566, ucf:50292
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005566
- Title
- PREDICTORS OF PRESENCE IN VIRTUAL REALITY.
- Creator
-
Sollins, Brandon, Beidel , Deborah, University of Central Florida
- Abstract / Description
-
The subjective experience of presence is considered to be important in the treatment of anxiety disorders using virtual reality. Presence can be defined as a psychological phenomenon through which one's cognitive processes are oriented towards another world. Most of the research on presence has focused on the roles of technological factors influencing presence, while the number of studies focusing on the personality and physiological predictors are far fewer. Thus, the present study examined...
Show moreThe subjective experience of presence is considered to be important in the treatment of anxiety disorders using virtual reality. Presence can be defined as a psychological phenomenon through which one's cognitive processes are oriented towards another world. Most of the research on presence has focused on the roles of technological factors influencing presence, while the number of studies focusing on the personality and physiological predictors are far fewer. Thus, the present study examined the relationship between various personality variables and presence, along with physiological correlates of presence when engaged in a virtual environment. The Presence Questionnaire, to determine their experience of presence, and a small battery of personality-related questionnaires were administered to 70 young adults who participated in 3 different virtual reality scenarios. Participants' physiological responses were recorded in the form of heart rate, galvanic skin levels, and galvanic skin responses were assessed as were urges to drink (craving). Data analysis showed that expectations, levels of craving, and drinking history played a significant role in the experience of presence.
Show less - Date Issued
- 2011
- Identifier
- CFH0003794, ucf:44754
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH0003794
- Title
- Personalized Digital Body: Enhancing Body Ownership and Spatial Presence in Virtual Reality.
- Creator
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Jung, Sungchul, Hughes, Charles, Foroosh, Hassan, Wisniewski, Pamela, Bruder, Gerd, Sandor, Christian, University of Central Florida
- Abstract / Description
-
person's sense of acceptance of a virtual body as his or her own is generally called virtual body ownership (VBOI). Having such a mental model of one's own body transferred to a virtual human surrogate is known to play a critical role in one's sense of presence in a virtual environment. Our focus in this dissertation is on top-down processing based on visual perception in both the visuomotor and the visuotactile domains, using visually personalized body cues. The visual cues we study here...
Show moreperson's sense of acceptance of a virtual body as his or her own is generally called virtual body ownership (VBOI). Having such a mental model of one's own body transferred to a virtual human surrogate is known to play a critical role in one's sense of presence in a virtual environment. Our focus in this dissertation is on top-down processing based on visual perception in both the visuomotor and the visuotactile domains, using visually personalized body cues. The visual cues we study here range from ones that we refer to as direct and others that we classify as indirect. Direct cues are associated with body parts that play a central role in the task we are performing. Such parts typically dominate a person's foveal view and will include one or both of their hands. Indirect body cues come from body parts that are normally seen in our peripheral view, e.g., legs and torso, and that are often observed through some mediation and are not directly associated with the current task.This dissertation studies how and to what degree direct and indirect cues affect a person's sense of VBOI for which they are receiving direct and, sometimes, inaccurate cues, and to investigate the relationship between enhanced virtual body ownership and task performance. Our experiments support the importance of a personalized representation, even for indirect cues. Additionally, we studied gradual versus instantaneous transition between one's own body and a virtual surrogate body, and between one's real-world environment and a virtual environment. We demonstrate that gradual transition has a significant influence on virtual body ownership and presence. In a follow-on study, we increase fidelity by using a personalized hand. Here, we demonstrate that a personalized hand significantly improves dominant visual illusions, resulting in more accurate perception of virtual object sizes.
Show less - Date Issued
- 2018
- Identifier
- CFE0007024, ucf:52033
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007024
- Title
- FIELD OF VIEW EFFECTS ON REFLEXIVE MOTOR RESPONSEIN FLIGHT SIMULATION.
- Creator
-
Covelli, Javier, Rolland, Jannick, University of Central Florida
- Abstract / Description
-
Virtual Reality (VR) and Augmented Reality (AR) Head Mounted Display (HMD) or Head Worn Display (HWD) technology represents low-cost, wide Field of Regard (FOR), deployable systems when compared to traditional simulation facilities. However, given current technological limitations, HWD flight simulator implementations provide a limited effective Field of View (eFOV) far narrower than the normal human 200º horizontal and 135º vertical FOV. Developing a HWD with such a wide FOV is...
Show moreVirtual Reality (VR) and Augmented Reality (AR) Head Mounted Display (HMD) or Head Worn Display (HWD) technology represents low-cost, wide Field of Regard (FOR), deployable systems when compared to traditional simulation facilities. However, given current technological limitations, HWD flight simulator implementations provide a limited effective Field of View (eFOV) far narrower than the normal human 200º horizontal and 135º vertical FOV. Developing a HWD with such a wide FOV is expensive but can increase the aviator's visual stimulus, perception, sense of presence and overall training effectiveness. This research and experimentation test this proposition by manipulating the eFOV of experienced pilots in a flight simulator while measuring their reflexive motor response and task performance. Reflexive motor responses are categorized as information, importance and effort behaviors. Performance metrics taken include runway alignment error (RAE) and vertical track error (VTE). Results indicated a significant and systematic change in visual scan pattern, head movement and flight control performance as the eFOV was sequentially decreased. As FOV decreased, the average visual scan pattern changed to focus less on out-the-window (OTW) and more on the instruments inside the cockpit. The head range of movement significantly increased below 80º horizontal x 54º vertical eFOV as well as significantly decreasing runway alignment and vertical track performance, which occurred below 120° horizontal x 81° vertical eFOV.
Show less - Date Issued
- 2008
- Identifier
- CFE0002002, ucf:47617
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002002
- Title
- USER-CENTERED VIRTUAL ENVIRONMENT ASSESSMENT AND DESIGN FOR COGNITIVE REHABILITATION APPLICATIONS.
- Creator
-
Fidopiastis, Cali, Rolland, Jannick, University of Central Florida
- Abstract / Description
-
Virtual environment (VE) design for cognitive rehabilitation necessitates a new methodology to ensure the validity of the resulting rehabilitation assessment. We propose that benchmarking the VE system technology utilizing a user-centered approach should precede the VE construction. Further, user performance baselines should be measured throughout testing as a control for adaptive effects that may confound the metrics chosen to evaluate the rehabilitation treatment. To support these claims we...
Show moreVirtual environment (VE) design for cognitive rehabilitation necessitates a new methodology to ensure the validity of the resulting rehabilitation assessment. We propose that benchmarking the VE system technology utilizing a user-centered approach should precede the VE construction. Further, user performance baselines should be measured throughout testing as a control for adaptive effects that may confound the metrics chosen to evaluate the rehabilitation treatment. To support these claims we present data obtained from two modules of a user-centered head-mounted display (HMD) assessment battery, specifically resolution visual acuity and stereoacuity. Resolution visual acuity and stereoacuity assessments provide information about the image quality achieved by an HMD based upon its unique system parameters. When applying a user-centered approach, we were able to quantify limitations in the VE system components (e.g., low microdisplay resolution) and separately point to user characteristics (e.g., changes in dark focus) that may introduce error in the evaluation of VE based rehabilitation protocols. Based on these results, we provide guidelines for calibrating and benchmarking HMDs. In addition, we discuss potential extensions of the assessment to address higher level usability issues. We intend to test the proposed framework within the Human Experience Modeler (HEM), a testbed created at the University of Central Florida to evaluate technologies that may enhance cognitive rehabilitation effectiveness. Preliminary results of a feasibility pilot study conducted with a memory impaired participant showed that the HEM provides the control and repeatability needed to conduct such technology comparisons. Further, the HEM affords the opportunity to integrate new brain imaging technologies (i.e., functional Near Infrared Imaging) to evaluate brain plasticity associated with VE based cognitive rehabilitation.
Show less - Date Issued
- 2006
- Identifier
- CFE0001203, ucf:46946
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001203
- Title
- MODELING, SIMULATION, AND VISUALIZATION OF 3D LUNG DYNAMICS.
- Creator
-
Santhanam, Anand, Rolland, Jannick, University of Central Florida
- Abstract / Description
-
Medical simulation has facilitated the understanding of complex biological phenomenon through its inherent explanatory power. It is a critical component for planning clinical interventions and analyzing its effect on a human subject. The success of medical simulation is evidenced by the fact that over one third of all medical schools in the United States augment their teaching curricula using patient simulators. Medical simulators present combat medics and emergency providers with video-based...
Show moreMedical simulation has facilitated the understanding of complex biological phenomenon through its inherent explanatory power. It is a critical component for planning clinical interventions and analyzing its effect on a human subject. The success of medical simulation is evidenced by the fact that over one third of all medical schools in the United States augment their teaching curricula using patient simulators. Medical simulators present combat medics and emergency providers with video-based descriptions of patient symptoms along with step-by-step instructions on clinical procedures that alleviate the patient's condition. Recent advances in clinical imaging technology have led to an effective medical visualization by coupling medical simulations with patient-specific anatomical models and their physically and physiologically realistic organ deformation. 3D physically-based deformable lung models obtained from a human subject are tools for representing regional lung structure and function analysis. Static imaging techniques such as Magnetic Resonance Imaging (MRI), Chest x-rays, and Computed Tomography (CT) are conventionally used to estimate the extent of pulmonary disease and to establish available courses for clinical intervention. The predictive accuracy and evaluative strength of the static imaging techniques may be augmented by improved computer technologies and graphical rendering techniques that can transform these static images into dynamic representations of subject specific organ deformations. By creating physically based 3D simulation and visualization, 3D deformable models obtained from subject-specific lung images will better represent lung structure and function. Variations in overall lung deformations may indicate tissue pathologies, thus 3D visualization of functioning lungs may also provide a visual tool to current diagnostic methods. The feasibility of medical visualization using static 3D lungs as an effective tool for endotracheal intubation was previously shown using Augmented Reality (AR) based techniques in one of the several research efforts at the Optical Diagnostics and Applications Laboratory (ODALAB). This research effort also shed light on the potential usage of coupling such medical visualization with dynamic 3D lungs. The purpose of this dissertation is to develop 3D deformable lung models, which are developed from subject-specific high resolution CT data and can be visualized using the AR based environment. A review of the literature illustrates that the techniques for modeling real-time 3D lung dynamics can be roughly grouped into two categories: Geometrically-based and Physically-based. Additional classifications would include considering a 3D lung model as either a volumetric or surface model, modeling the lungs as either a single-compartment or a multi-compartment, modeling either the air-blood interaction or the air-blood-tissue interaction, and considering either a normal or pathophysical behavior of lungs. Validating the simulated lung dynamics is a complex problem and has been previously approached by tracking a set of landmarks on the CT images. An area that needs to be explored is the relationship between the choice of the deformation method for the 3D lung dynamics and its visualization framework. Constraints on the choice of the deformation method and the 3D model resolution arise from the visualization framework. Such constraints of our interest are the real-time requirement and the level of interaction required with the 3D lung models. The work presented here discusses a framework that facilitates a physics-based and physiology-based deformation of a single-compartment surface lung model that maintains the frame-rate requirements of the visualization system. The framework presented here is part of several research efforts at ODALab for developing an AR based medical visualization framework. The framework consists of 3 components, (i) modeling the Pressure-Volume (PV) relation, (ii) modeling the lung deformation using a Green's function based deformation operator, and (iii) optimizing the deformation using state-of-art Graphics Processing Units (GPU). The validation of the results obtained in the first two modeling steps is also discussed for normal human subjects. Disease states such as Pneumothorax and lung tumors are modeled using the proposed deformation method. Additionally, a method to synchronize the instantiations of the deformation across a network is also discussed.
Show less - Date Issued
- 2006
- Identifier
- CFE0001301, ucf:47033
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001301
