The Fidelity of ’Feel’: Emotional Affordance in Virtual Environments
2005-07-01
The Fidelity of “Feel”: Emotional Affordance in Virtual Environments Jacquelyn Ford Morie, Josh Williams, Aimee Dozois, Donat-Pierre Luigi... environment but also the participant. We do this with the focus on what emotional affordances this manipulation will provide. Our first evaluation scenario...emotionally affective VEs. Keywords: Immersive Environments , Virtual Environments , VEs, Virtual Reality, emotion , affordance, fidelity, presence
The ALIVE Project: Astronomy Learning in Immersive Virtual Environments
NASA Astrophysics Data System (ADS)
Yu, K. C.; Sahami, K.; Denn, G.
2008-06-01
The Astronomy Learning in Immersive Virtual Environments (ALIVE) project seeks to discover learning modes and optimal teaching strategies using immersive virtual environments (VEs). VEs are computer-generated, three-dimensional environments that can be navigated to provide multiple perspectives. Immersive VEs provide the additional benefit of surrounding a viewer with the simulated reality. ALIVE evaluates the incorporation of an interactive, real-time ``virtual universe'' into formal college astronomy education. In the experiment, pre-course, post-course, and curriculum tests will be used to determine the efficacy of immersive visualizations presented in a digital planetarium versus the same visual simulations in the non-immersive setting of a normal classroom, as well as a control case using traditional classroom multimedia. To normalize for inter-instructor variability, each ALIVE instructor will teach at least one of each class in each of the three test groups.
Avatars, Pedagogical Agents, and Virtual Environments: Social Learning Systems Online
ERIC Educational Resources Information Center
Ausburn, Lynna J.; Martens, Jon; Dotterer, Gary; Calhoun, Pat
2009-01-01
This paper presents a review of literature that introduces major concepts and issues in using avatars and pedagogical agents in first- and second-person virtual environments (VEs) for learning online. In these VEs, avatars and pedagogical agents represent self and other learners/participants or serve as personal learning "guides". The…
Using Immersive Virtual Environments for Certification
NASA Technical Reports Server (NTRS)
Lutz, R.; Cruz-Neira, C.
1998-01-01
Immersive virtual environments (VEs) technology has matured to the point where it can be utilized as a scientific and engineering problem solving tool. In particular, VEs are starting to be used to design and evaluate safety-critical systems that involve human operators, such as flight and driving simulators, complex machinery training, and emergency rescue strategies.
ERIC Educational Resources Information Center
Foreman, Nigel
2009-01-01
The benefits of using virtual environments (VEs) in psychology arise from the fact that movements in virtual space, and accompanying perceptual changes, are treated by the brain in much the same way as those in equivalent real space. The research benefits of using VEs, in areas of psychology such as spatial learning and cognition, include…
ERIC Educational Resources Information Center
Parsons, Sarah; Mitchell, Peter; Leonard, Anne
2005-01-01
The potential for using virtual environments (VEs) in educational contexts for people with autistic spectrum disorders (ASDs) has been recognized. However, very little is known about how people with ASDs interpret and understand VEs. This study aimed to investigate this directly with a group of 12 adolescents with ASDs, each individually matched…
Collaborative voxel-based surgical virtual environments.
Acosta, Eric; Muniz, Gilbert; Armonda, Rocco; Bowyer, Mark; Liu, Alan
2008-01-01
Virtual Reality-based surgical simulators can utilize Collaborative Virtual Environments (C-VEs) to provide team-based training. To support real-time interactions, C-VEs are typically replicated on each user's local computer and a synchronization method helps keep all local copies consistent. This approach does not work well for voxel-based C-VEs since large and frequent volumetric updates make synchronization difficult. This paper describes a method that allows multiple users to interact within a voxel-based C-VE for a craniotomy simulator being developed. Our C-VE method requires smaller update sizes and provides faster synchronization update rates than volumetric-based methods. Additionally, we address network bandwidth/latency issues to simulate networked haptic and bone drilling tool interactions with a voxel-based skull C-VE.
Bugnariu, Nicoleta L.
2016-01-01
Abstract Virtual environments (VEs) may be useful for delivering social skills interventions to individuals with autism spectrum disorder (ASD). Immersive VEs provide opportunities for individuals with ASD to learn and practice skills in a controlled replicable setting. However, not all VEs are delivered using the same technology, and the level of immersion differs across settings. We group studies into low-, moderate-, and high-immersion categories by examining five aspects of immersion. In doing so, we draw conclusions regarding the influence of this technical manipulation on the efficacy of VEs as a tool for assessing and teaching social skills. We also highlight ways in which future studies can advance our understanding of how manipulating aspects of immersion may impact intervention success. PMID:26919157
Makssoud, Hassan El; Richards, Carol L; Comeau, François
2009-01-01
Virtual reality (VR) technology offers the opportunity to expose patients to complex physical environments without physical danger and thus provides a wide range of opportunities for locomotor training or the study of human postural and walking behavior. A VR-based locomotor training system has been developed for gait rehabilitation post-stroke. A clinical study has shown that persons after stroke are able to adapt and benefit from this novel system wherein they walk into virtual environments (VEs) on a self-paced treadmill mounted on a platform with 6 degrees of freedom. This platform is programmed to mimic changes in the terrain encountered in the VEs. While engaging in these VEs, excessive trunk movements and speed alterations have been observed, especially during the pitch perturbations accompanying uphill or downhill terrain changes. An in-depth study of the subject's behavior in relation to the platform movements revealed that the platform rotational axes need to be modified, as previously shown by Barton et al, and in addition did not consider the subject's position on the treadmill. The aim of this study was to determine an optimal solution to simulate walking in real life when engaging in VEs.
ERIC Educational Resources Information Center
Ehrlich, Justin
2010-01-01
The application of virtual reality is becoming ever more important as technology reaches new heights allowing virtual environments (VE) complete with global illumination. One successful application of virtual environments is educational interventions meant to treat individuals with autism spectrum disorder (ASD). VEs are effective with these…
A survey on virtual environment applications to fear of public speaking.
Vanni, F; Conversano, C; Del Debbio, A; Landi, P; Carlini, M; Fanciullacci, C; Bergamasco, M; Di Fiorino, A; Dell'Osso, L
2013-06-01
Social Anxiety Disorder (SAD) is one of the most prevalent anxiety disorders in Europe and comprises the fear of public speaking as its typical sub-type. Cognitive-Behavioural Therapy (CBT) is the intervention of choice for SAD, and it includes exposure to anxiety-provoking stimuli to induce systematic desensitization and reduce anxiety. Similarly, exposure therapy per se has been used and found effective, although it is not as specific as CBT for the treatment of SAD. Interestingly, exposure to anxiety-provoking situations can be achieved in Virtual Environments (VEs) through the simulation of social situations allowing individuals with public speaking anxiety to live and develop real exposure-like reactions. The Virtual Reality Exposure Therapy (VRET) is the treatment of anxiety disorders based on such VEs. This article aims to provide an overview of the scientific literature related to the applications of Virtual Reality to the treatment of fear of public speaking. We conducted the literature review on PubMed and Google Scholar for studies including the fear-of-public-speaking VEs. Reviewed studies addressed two main aspects: the design parameters of the VEs for adequate reactions to synthetic social stimuli, and the efficacy of VEs for fear of public speaking treatment. VEs resulted effective for triggering as-if-real reactions in relation to public speaking. VE-based exposures reduced public speaking anxiety measurements, decreased scores and maintained them at 3 month follow-up. Studies comparing VRET to pharmacological therapy are lacking, and there are few randomized controlled trials that compare VRET to CBT, especially on fear of public speaking treatment.
Designing Awe in Virtual Reality: An Experimental Study.
Chirico, Alice; Ferrise, Francesco; Cordella, Lorenzo; Gaggioli, Andrea
2017-01-01
Awe is a little-studied emotion with a great transformative potential. Therefore, the interest toward the study of awe's underlying mechanisms has been increased. Specifically, researchers have been interested in how to reproduce intense feelings of awe within laboratory conditions. It has been proposed that the use of virtual reality (VR) could be an effective way to induce awe in controlled experimental settings, thanks to its ability of providing participants with a sense of "presence," that is, the subjective feeling of being displaced in another physical or imaginary place. However, the potential of VR as awe-inducing medium has not been fully tested yet. In the present study, we provided an evidence-based design and a validation of four immersive virtual environments (VEs) involving 36 participants in a within-subject design. Of these, three VEs were designed to induce awe, whereas the fourth VE was targeted as an emotionally neutral stimulus. Participants self-reported the extent to which they felt awe, general affect and sense of presence related to each environment. As expected, results showed that awe-VEs could induce significantly higher levels of awe and presence as compared to the neutral VE. Furthermore, these VEs induced significantly more positive than negative affect. These findings supported the potential of immersive VR for inducing awe and provide useful indications for the design of awe-inspiring virtual environments.
Tuning self-motion perception in virtual reality with visual illusions.
Bruder, Gerd; Steinicke, Frank; Wieland, Phil; Lappe, Markus
2012-07-01
Motion perception in immersive virtual environments significantly differs from the real world. For example, previous work has shown that users tend to underestimate travel distances in virtual environments (VEs). As a solution to this problem, researchers proposed to scale the mapped virtual camera motion relative to the tracked real-world movement of a user until real and virtual motion are perceived as equal, i.e., real-world movements could be mapped with a larger gain to the VE in order to compensate for the underestimation. However, introducing discrepancies between real and virtual motion can become a problem, in particular, due to misalignments of both worlds and distorted space cognition. In this paper, we describe a different approach that introduces apparent self-motion illusions by manipulating optic flow fields during movements in VEs. These manipulations can affect self-motion perception in VEs, but omit a quantitative discrepancy between real and virtual motions. In particular, we consider to which regions of the virtual view these apparent self-motion illusions can be applied, i.e., the ground plane or peripheral vision. Therefore, we introduce four illusions and show in experiments that optic flow manipulation can significantly affect users' self-motion judgments. Furthermore, we show that with such manipulations of optic flow fields the underestimation of travel distances can be compensated.
Vecchiato, Giovanni; Tieri, Gaetano; Jelic, Andrea; De Matteis, Federico; Maglione, Anton G; Babiloni, Fabio
2015-01-01
Nowadays there is the hope that neuroscientific findings will contribute to the improvement of building design in order to create environments which satisfy man's demands. This can be achieved through the understanding of neurophysiological correlates of architectural perception. To this aim, the electroencephalographic (EEG) signals of 12 healthy subjects were recorded during the perception of three immersive virtual reality environments (VEs). Afterwards, participants were asked to describe their experience in terms of Familiarity, Novelty, Comfort, Pleasantness, Arousal, and Presence using a rating scale from 1 to 9. These perceptual dimensions are hypothesized to influence the pattern of cerebral spectral activity, while Presence is used to assess the realism of the virtual stimulation. Hence, the collected scores were used to analyze the Power Spectral Density (PSD) of the EEG for each behavioral dimension in the theta, alpha and mu bands by means of time-frequency analysis and topographic statistical maps. Analysis of Presence resulted in the activation of the frontal-midline theta, indicating the involvement of sensorimotor integration mechanisms when subjects expressed to feel more present in the VEs. Similar patterns also characterized the experience of familiar and comfortable VEs. In addition, pleasant VEs increased the theta power across visuomotor circuits and activated the alpha band in areas devoted to visuospatial exploration and processing of categorical spatial relations. Finally, the de-synchronization of the mu rhythm described the perception of pleasant and comfortable VEs, showing the involvement of left motor areas and embodied mechanisms for environment appreciation. Overall, these results show the possibility to measure EEG correlates of architectural perception involving the cerebral circuits of sensorimotor integration, spatial navigation, and embodiment. These observations can help testing architectural hypotheses in order to design environments matching the changing needs of humans.
Vecchiato, Giovanni; Tieri, Gaetano; Jelic, Andrea; De Matteis, Federico; Maglione, Anton G.; Babiloni, Fabio
2015-01-01
Nowadays there is the hope that neuroscientific findings will contribute to the improvement of building design in order to create environments which satisfy man's demands. This can be achieved through the understanding of neurophysiological correlates of architectural perception. To this aim, the electroencephalographic (EEG) signals of 12 healthy subjects were recorded during the perception of three immersive virtual reality environments (VEs). Afterwards, participants were asked to describe their experience in terms of Familiarity, Novelty, Comfort, Pleasantness, Arousal, and Presence using a rating scale from 1 to 9. These perceptual dimensions are hypothesized to influence the pattern of cerebral spectral activity, while Presence is used to assess the realism of the virtual stimulation. Hence, the collected scores were used to analyze the Power Spectral Density (PSD) of the EEG for each behavioral dimension in the theta, alpha and mu bands by means of time-frequency analysis and topographic statistical maps. Analysis of Presence resulted in the activation of the frontal-midline theta, indicating the involvement of sensorimotor integration mechanisms when subjects expressed to feel more present in the VEs. Similar patterns also characterized the experience of familiar and comfortable VEs. In addition, pleasant VEs increased the theta power across visuomotor circuits and activated the alpha band in areas devoted to visuospatial exploration and processing of categorical spatial relations. Finally, the de-synchronization of the mu rhythm described the perception of pleasant and comfortable VEs, showing the involvement of left motor areas and embodied mechanisms for environment appreciation. Overall, these results show the possibility to measure EEG correlates of architectural perception involving the cerebral circuits of sensorimotor integration, spatial navigation, and embodiment. These observations can help testing architectural hypotheses in order to design environments matching the changing needs of humans. PMID:26733924
Impact of Virtual Environments on Sensorimotor Coordination and User Safety
NASA Technical Reports Server (NTRS)
Harm, Deborah L.; Taylor, Laura C.; Kennedy, Robert S.; Reschke, Millard F.
2011-01-01
One critical unresolved issue related to the safe use of virtual environments (VEs) is maladaptive sensorimotor coordination following exposure to VEs. Moving visual displays used in VEs, especially in the absence of concordant vestibular signals leads to adaptive responses during VE exposure, but maladaptive responses following return to the normal environment. In the current set of investigations, we examined the effect of HMD and dome VE displays on eye-head-hand coordination, gaze holding and postural equilibrium. Subjects (61) performed a navigation and a pick and place task. Further, we compared 30 min and 60 min exposures across 3 days (each separated by 1 day). A subset of these results will be presented. In general, we found significant decrements in all three measures following exposure to the VEs. In addition, we found that these disturbances generally recovered within 1-2 hrs and decreased across days. These findings suggest the need for post-VE monitoring of sensorimotor coordination and for developing a set of recommendations for users concerning activities that are safe to engage in following use of a VE.
Diabetes Self-management Training in a Virtual Environment.
Reagan, Louise; Pereira, Katherine; Jefferson, Vanessa; Evans Kreider, Kathryn; Totten, Susan; D'Eramo Melkus, Gail; Johnson, Constance; Vorderstrasse, Allison
2017-08-01
Diabetes self-management training (DSMT) improves diabetes health outcomes. However, low numbers of patients receive DSMT. Using virtual environments (VEs) for DSMT is an innovative approach to removing barriers for patients. The purpose of this paper is to describe the experience of health professionals and diabetes educators establishing and teaching DSMT in a VE, Diabetes LIVE© (Learning in Virtual Environments), and the implications for future use of VEs in DSMT. It was found that providing DSMT in a VE preserves real-time interaction between patients and educators. To facilitate ongoing patient learning and engagement, the DSMT curriculum was expanded beyond the core content as "Above and Beyond" topics. Using a VE for DSMT presents challenges and opportunities. Challenges include overcoming technological barriers and improving comfort levels to orient educators and patients to the functionality of the VE. Opportunities include overcoming barriers to reaching patients, particularly given the diabetes epidemic and relatively small number of diabetes educators. Using a VE also affords a simulated community for experiential learning. VEs may become powerful tools for diabetes and other health educators to reach patients. Ongoing education and support are vital to successful self-management of chronic disease.
Virtual Environments and Autism: A Developmental Psychopathological Approach
ERIC Educational Resources Information Center
Rajendran, G.
2013-01-01
Individuals with autism spectrum disorders supposedly have an affinity with information and communication technology (ICT), making it an ideally suited media for this population. Virtual environments (VEs)--both two-dimensional and immersive--represent a particular kind of ICT that might be of special benefit. Specifically, this paper discusses…
ERIC Educational Resources Information Center
Chen, Chwen Jen; Fauzy Wan Ismail, Wan Mohd
2008-01-01
The real-time interactive nature of three-dimensional virtual environments (VEs) makes this technology very appropriate for exploratory learning purposes. However, many studies have shown that the exploration process may cause cognitive overload that affects the learning of domain knowledge. This article reports a quasi-experimental study that…
ERIC Educational Resources Information Center
Waller, David; Richardson, Adam R.
2008-01-01
The tendency to underestimate egocentric distances in immersive virtual environments (VEs) is not well understood. However, previous research (A. R. Richardson & D. Waller, 2007) has demonstrated that a brief period of interaction with the VE prior to making distance judgments can effectively eliminate subsequent underestimation. Here the authors…
ERIC Educational Resources Information Center
Parsons, Sarah; Leonard, Anne; Mitchell, Peter
2006-01-01
Previous research has shown that computer-based tasks can motivate people with autism and encourage learning. As a computer-based medium, Virtual Environments (VEs) offer a potentially useful tool for social skills training for people with autistic spectrum disorders (ASDs). However, there are some concerns over whether people with ASDs can…
ERIC Educational Resources Information Center
Vasquez, Eleazar, III; Nagendran, Arjun; Welch, Gregory F.; Marino, Matthew T.; Hughes, Darin E.; Koch, Aaron; Delisio, Lauren
2015-01-01
Students with autism spectrum disorder (ASD) show varying levels of impairment in social skills situations. Interventions have been developed utilizing virtual environments (VEs) to teach and improve social skills. This article presents a systematic literature review of peer-reviewed journal articles focusing on social interventions in VEs…
Kozlov, Michail D; Johansen, Mark K
2010-12-01
The purpose of this research was to illustrate the broad usefulness of simple video-game-based virtual environments (VEs) for psychological research on real-world behavior. To this end, this research explored several high-level social phenomena in a simple, inexpensive computer-game environment: the reduced likelihood of helping under time pressure and the bystander effect, which is reduced helping in the presence of bystanders. In the first experiment, participants had to find the exit in a virtual labyrinth under either high or low time pressure. They encountered rooms with and without virtual bystanders, and in each room, a virtual person requested assistance. Participants helped significantly less frequently under time pressure but the presence/absence of a small number of bystanders did not significantly moderate helping. The second experiment increased the number of virtual bystanders, and participants were instructed to imagine that these were real people. Participants helped significantly less in rooms with large numbers of bystanders compared to rooms with no bystanders, thus demonstrating a bystander effect. These results indicate that even sophisticated high-level social behaviors can be observed and experimentally manipulated in simple VEs, thus implying the broad usefulness of this paradigm in psychological research as a good compromise between experimental control and ecological validity.
ERIC Educational Resources Information Center
Choi, Gil Ok
2008-01-01
For the past few years, virtual environments (VEs) have gained broad attention from both scholarly and practitioner communities. However, in spite of intense and widespread efforts, most VE-related research has focused on the technical aspects of applications, and the necessary theoretical framework to assess the quality of interfaces and designs…
ERIC Educational Resources Information Center
Lockwood, Nicholas S.
2011-01-01
Geographically dispersed teams rely on information and communication technologies (ICTs) to communicate and collaborate. Three ICTs that have received attention are audio conferencing (AC), video conferencing (VC), and, recently, 3D virtual environments (3D VEs). These ICTs offer modes of communication that differ primarily in the number and type…
ERIC Educational Resources Information Center
Korallo, Liliya; Foreman, Nigel; Boyd-Davis, Stephen; Moar, Magnus; Coulson, Mark
2012-01-01
Studies examined the potential use of VEs in teaching historical chronology to 127 children of primary school age (8-9 years). The use of passive fly-through VEs had been found, in an earlier study, to be disadvantageous with this age group when tested for their subsequent ability to place displayed sequential events in correct chronological…
Pollock, Brice; Burton, Melissa; Kelly, Jonathan W; Gilbert, Stephen; Winer, Eliot
2012-04-01
Stereoscopic depth cues improve depth perception and increase immersion within virtual environments (VEs). However, improper display of these cues can distort perceived distances and directions. Consider a multi-user VE, where all users view identical stereoscopic images regardless of physical location. In this scenario, cues are typically customized for one "leader" equipped with a head-tracking device. This user stands at the center of projection (CoP) and all other users ("followers") view the scene from other locations and receive improper depth cues. This paper examines perceived depth distortion when viewing stereoscopic VEs from follower perspectives and the impact of these distortions on collaborative spatial judgments. Pairs of participants made collaborative depth judgments of virtual shapes viewed from the CoP or after displacement forward or backward. Forward and backward displacement caused perceived depth compression and expansion, respectively, with greater compression than expansion. Furthermore, distortion was less than predicted by a ray-intersection model of stereo geometry. Collaboration times were significantly longer when participants stood at different locations compared to the same location, and increased with greater perceived depth discrepancy between the two viewing locations. These findings advance our understanding of spatial distortions in multi-user VEs, and suggest a strategy for reducing distortion.
Zhou, Y; Murata, T; Defanti, T A
2000-01-01
Despite their attractive properties, networked virtual environments (net-VEs) are notoriously difficult to design, implement, and test due to the concurrency, real-time and networking features in these systems. Net-VEs demand high quality-of-service (QoS) requirements on the network to maintain natural and real-time interactions among users. The current practice for net-VE design is basically trial and error, empirical, and totally lacks formal methods. This paper proposes to apply a Petri net formal modeling technique to a net-VE-NICE (narrative immersive constructionist/collaborative environment), predict the net-VE performance based on simulation, and improve the net-VE performance. NICE is essentially a network of collaborative virtual reality systems called the CAVE-(CAVE automatic virtual environment). First, we introduce extended fuzzy-timing Petri net (EFTN) modeling and analysis techniques. Then, we present EFTN models of the CAVE, NICE, and transport layer protocol used in NICE: transmission control protocol (TCP). We show the possibility analysis based on the EFTN model for the CAVE. Then, by using these models and design/CPN as the simulation tool, we conducted various simulations to study real-time behavior, network effects and performance (latencies and jitters) of NICE. Our simulation results are consistent with experimental data.
Virtual Heritage Tours: Developing Interactive Narrative-Based Environments for Historical Sites
NASA Astrophysics Data System (ADS)
Tuck, Deborah; Kuksa, Iryna
In the last decade there has been a noticeable growth in the use of virtual reality (VR) technologies for reconstructing cultural heritage sites. However, many of these virtual reconstructions evidence little of sites' social histories. Narrating the Past is a research project that aims to re-address this issue by investigating methods for embedding social histories within cultural heritage sites and by creating narrative based virtual environments (VEs) within them. The project aims to enhance the visitor's knowledge and understanding by developing a navigable 3D story space, in which participants are immersed. This has the potential to create a malleable virtual environment allowing the visitor to configure their own narrative paths.
NASA Astrophysics Data System (ADS)
Zhang, Wenyu; Zhang, Shuai; Cai, Ming; Jian, Wu
2015-04-01
With the development of virtual enterprise (VE) paradigm, the usage of serviceoriented architecture (SOA) is increasingly being considered for facilitating the integration and utilisation of distributed manufacturing resources. However, due to the heterogeneous nature among VEs, the dynamic nature of a VE and the autonomous nature of each VE member, the lack of both sophisticated coordination mechanism in the popular centralised infrastructure and semantic expressivity in the existing SOA standards make the current centralised, syntactic service discovery method undesirable. This motivates the proposed agent-based peer-to-peer (P2P) architecture for semantic discovery of manufacturing services across VEs. Multi-agent technology provides autonomous and flexible problemsolving capabilities in dynamic and adaptive VE environments. Peer-to-peer overlay provides highly scalable coupling across decentralised VEs, each of which exhibiting as a peer composed of multiple agents dealing with manufacturing services. The proposed architecture utilises a novel, efficient, two-stage search strategy - semantic peer discovery and semantic service discovery - to handle the complex searches of manufacturing services across VEs through fast peer filtering. The operation and experimental evaluation of the prototype system are presented to validate the implementation of the proposed approach.
Kothgassner, Oswald D; Goreis, Andreas; Kafka, Johanna X; Hlavacs, Helmut; Beutl, Leon; Kryspin-Exner, Ilse; Felnhofer, Anna
2018-05-01
While virtual humans are increasingly used to benefit the elderly, considerably little is still known about older adults' virtual experiences. However, due to age-related changes, older adults' perceptions of virtual environments (VEs) may be unique. Hence, our objective was to examine possible gender differences in immersion, flow, and emotional states as well as physical and social presence in elderly males and females interacting either with a computer-controlled agent or a human-controlled avatar. Seventy-eight German-speaking older adults were randomly assigned to an avatar or an agent condition and were exposed to a brief social encounter in a virtual café. Results indicate no overall gender differences, but a significant effect of agency on social presence, physical presence, immersion, and flow. Participants in the avatar condition reported higher levels in all measures, except for involvement. Furthermore, significant gender × agency interactions were found, with females showing more social presence, spatial presence, and flow when interacting with a human-controlled avatar and more realism when conversing with an agent. Also, all participants showed significant changes in their affect post exposure. In sum, older adults' virtual experiences seem to follow unique patterns, yet, they do not preclude the elderly from successfully participating in VEs.
Merians, Alma S; Fluet, Gerard G; Qiu, Qinyin; Lafond, Ian; Adamovich, Sergei V
2011-01-01
Robotic systems that are interfaced with virtual reality gaming and task simulations are increasingly being developed to provide repetitive intensive practice to promote increased compliance and facilitate better outcomes in rehabilitation post-stroke. A major development in the use of virtual environments (VEs) has been to incorporate tactile information and interaction forces into what was previously an essentially visual experience. Robots of varying complexity are being interfaced with more traditional virtual presentations to provide haptic feedback that enriches the sensory experience and adds physical task parameters. This provides forces that produce biomechanical and neuromuscular interactions with the VE that approximate real-world movement more accurately than visual-only VEs, simulating the weight and force found in upper extremity tasks. The purpose of this article is to present an overview of several systems that are commercially available for ambulation training and for training movement of the upper extremity. We will also report on the system that we have developed (NJIT-RAVR system) that incorporates motivating and challenging haptic feedback effects into VE simulations to facilitate motor recovery of the upper extremity post-stroke. The NJIT-RAVR system trains both the upper arm and the hand. The robotic arm acts as an interface between the participants and the VEs, enabling multiplanar movements against gravity in a three-dimensional workspace. The ultimate question is whether this medium can provide a motivating, challenging, gaming experience with dramatically decreased physical difficulty levels, which would allow for participation by an obese person and facilitate greater adherence to exercise regimes. PMID:21527097
Sankaranarayanan, Ganesh; Halic, Tansel; Arikatla, Venkata Sreekanth; Lu, Zhonghua; De, Suvranu
2010-01-01
Purpose Surgical simulations require haptic interactions and collaboration in a shared virtual environment. A software framework for decoupled surgical simulation based on a multi-controller and multi-viewer model-view-controller (MVC) pattern was developed and tested. Methods A software framework for multimodal virtual environments was designed, supporting both visual interactions and haptic feedback while providing developers with an integration tool for heterogeneous architectures maintaining high performance, simplicity of implementation, and straightforward extension. The framework uses decoupled simulation with updates of over 1,000 Hz for haptics and accommodates networked simulation with delays of over 1,000 ms without performance penalty. Results The simulation software framework was implemented and was used to support the design of virtual reality-based surgery simulation systems. The framework supports the high level of complexity of such applications and the fast response required for interaction with haptics. The efficacy of the framework was tested by implementation of a minimally invasive surgery simulator. Conclusion A decoupled simulation approach can be implemented as a framework to handle simultaneous processes of the system at the various frame rates each process requires. The framework was successfully used to develop collaborative virtual environments (VEs) involving geographically distributed users connected through a network, with the results comparable to VEs for local users. PMID:20714933
Maciel, Anderson; Sankaranarayanan, Ganesh; Halic, Tansel; Arikatla, Venkata Sreekanth; Lu, Zhonghua; De, Suvranu
2011-07-01
Surgical simulations require haptic interactions and collaboration in a shared virtual environment. A software framework for decoupled surgical simulation based on a multi-controller and multi-viewer model-view-controller (MVC) pattern was developed and tested. A software framework for multimodal virtual environments was designed, supporting both visual interactions and haptic feedback while providing developers with an integration tool for heterogeneous architectures maintaining high performance, simplicity of implementation, and straightforward extension. The framework uses decoupled simulation with updates of over 1,000 Hz for haptics and accommodates networked simulation with delays of over 1,000 ms without performance penalty. The simulation software framework was implemented and was used to support the design of virtual reality-based surgery simulation systems. The framework supports the high level of complexity of such applications and the fast response required for interaction with haptics. The efficacy of the framework was tested by implementation of a minimally invasive surgery simulator. A decoupled simulation approach can be implemented as a framework to handle simultaneous processes of the system at the various frame rates each process requires. The framework was successfully used to develop collaborative virtual environments (VEs) involving geographically distributed users connected through a network, with the results comparable to VEs for local users.
Stanton, D; Foreman, N; Wilson, P N
1998-01-01
In this chapter we review some of the ways in which the skills learned in virtual environments (VEs) transfer to real situations, and in particular how information about the spatial layouts of virtual buildings acquired from the exploration of three-dimensional computer-simulations transfers to their real equivalents. Four experiments are briefly described which examined VR use by disabled children. We conclude that spatial information of the kind required for navigation transfers effectively from virtual to real situations. Spatial skills in disabled children showed progressive improvement with repeated exploration of virtual environments. The results are discussed in relation to the potential future benefits of VR in special needs education and training.
Merians, Alma S; Fluet, Gerard G; Qiu, Qinyin; Lafond, Ian; Adamovich, Sergei V
2011-03-01
Robotic systems that are interfaced with virtual reality gaming and task simulations are increasingly being developed to provide repetitive intensive practice to promote increased compliance and facilitate better outcomes in rehabilitation post-stroke. A major development in the use of virtual environments (VEs) has been to incorporate tactile information and interaction forces into what was previously an essentially visual experience. Robots of varying complexity are being interfaced with more traditional virtual presentations to provide haptic feedback that enriches the sensory experience and adds physical task parameters. This provides forces that produce biomechanical and neuromuscular interactions with the VE that approximate real-world movement more accurately than visual-only VEs, simulating the weight and force found in upper extremity tasks. The purpose of this article is to present an overview of several systems that are commercially available for ambulation training and for training movement of the upper extremity. We will also report on the system that we have developed (NJIT-RAVR system) that incorporates motivating and challenging haptic feedback effects into VE simulations to facilitate motor recovery of the upper extremity post-stroke. The NJIT-RAVR system trains both the upper arm and the hand. The robotic arm acts as an interface between the participants and the VEs, enabling multiplanar movements against gravity in a three-dimensional workspace. The ultimate question is whether this medium can provide a motivating, challenging, gaming experience with dramatically decreased physical difficulty levels, which would allow for participation by an obese person and facilitate greater adherence to exercise regimes. © 2011 Diabetes Technology Society.
Enrichment of Human-Computer Interaction in Brain-Computer Interfaces via Virtual Environments
Víctor Rodrigo, Mercado-García
2017-01-01
Tridimensional representations stimulate cognitive processes that are the core and foundation of human-computer interaction (HCI). Those cognitive processes take place while a user navigates and explores a virtual environment (VE) and are mainly related to spatial memory storage, attention, and perception. VEs have many distinctive features (e.g., involvement, immersion, and presence) that can significantly improve HCI in highly demanding and interactive systems such as brain-computer interfaces (BCI). BCI is as a nonmuscular communication channel that attempts to reestablish the interaction between an individual and his/her environment. Although BCI research started in the sixties, this technology is not efficient or reliable yet for everyone at any time. Over the past few years, researchers have argued that main BCI flaws could be associated with HCI issues. The evidence presented thus far shows that VEs can (1) set out working environmental conditions, (2) maximize the efficiency of BCI control panels, (3) implement navigation systems based not only on user intentions but also on user emotions, and (4) regulate user mental state to increase the differentiation between control and noncontrol modalities. PMID:29317861
Female artists and the VR crucible: expanding the aesthetic vocabulary
NASA Astrophysics Data System (ADS)
Morie, Jacquelyn Ford
2012-03-01
Virtual Reality was a technological wonder in its early days, and it was widely held to be a domain where men were the main practitioners. However, a survey done in 2007 of VR Artworks (Immersive Virtual Environments or VEs) showed that women have actually created the majority of artistic immersive works. This argues against the popular idea that the field has been totally dominated by men. While men have made great contributions in advancing the field, especially technologically, it appears most artistic works emerge from a decidedly feminine approach. Such an approach seems well suited to immersive environments as it incorporates aspects of inclusion, wholeness, and a blending of the body and the spirit. Female attention to holistic concerns fits the gestalt approach needed to create in a fully functional yet open-ended virtual world, which focuses not so much on producing a finished object (like a text or a sculpture) but rather on creating a possibility for becoming, like bringing a child into the world. Immersive VEs are not objective works of art to be hung on a wall and critiqued. They are vehicles for experience, vessels to live within for a piece of time.
Mental rotation - A key to mitigation of motion sickness in the virtual environments?
NASA Technical Reports Server (NTRS)
Parker, Donald E.; Harm, Deborah L.
1992-01-01
If mental rotation is important for the reduction of motion sickness and complement performance in virtual environments (VEs), the use of the Howard (1982) mental rotation test battery may identify individuals with lower susceptibility to VE-induced motion sickness and therefore a greater probability of success as VE operators. An apparatus and its associated procedures are currently under development for astronaut microgravity training aimed at reducing motion sickness; it is hypothesized that this system may be of significance to VE testing and training.
ERIC Educational Resources Information Center
Gilford, J.; Falconer, R. E.; Wade, R.; Scott-Brown, K. C.
2014-01-01
Interactive Virtual Environments (VEs) have the potential to increase student interest in soil science. Accordingly a bespoke "soil atlas" was created using Java3D as an interactive 3D VE, to show soil information in the context of (and as affected by) the over-lying landscape. To display the below-ground soil characteristics, four sets…
2018-01-01
Background Virtual environments (VEs) facilitate interaction and support among individuals with chronic illness, yet the characteristics of these VE interactions remain unknown. Objective The objective of this study was to describe social interaction and support among individuals with type 2 diabetes (T2D) who interacted in a VE. Methods Data included VE-mediated synchronous conversations and text-chat and asynchronous emails and discussion board posts from a study that facilitated interaction among individuals with T2D and diabetes educators (N=24) in 2 types of sessions: education and support. Results VE interactions consisted of communication techniques (how individuals interact in the VE), expressions of self-management (T2D-related topics), depth (personalization of topics), and breadth (number of topics discussed). Individuals exchanged support more often in the education (723/1170, 61.79%) than in the support (406/1170, 34.70%) sessions or outside session time (41/1170, 3.50%). Of all support exchanges, 535/1170 (45.73%) were informational, 377/1170 (32.22%) were emotional, 217/1170 (18.55%) were appraisal, and 41/1170 (3.50%) were instrumental. When comparing session types, education sessions predominately provided informational support (357/723, 49.4%), and the support sessions predominately provided emotional (159/406, 39.2%) and informational (159/406, 39.2%) support. Conclusions VE-mediated interactions resemble those in face-to-face environments, as individuals in VEs engage in bidirectional exchanges with others to obtain self-management education and support. Similar to face-to-face environments, individuals in the VE revealed personal information, sought information, and exchanged support during the moderated education sessions and unstructured support sessions. With this versatility, VEs are able to contribute substantially to support for those with diabetes and, very likely, other chronic diseases. PMID:29467118
Blocking of Goal-Location Learning Based on Shape
ERIC Educational Resources Information Center
Alexander, Tim; Wilson, Stuart P.; Wilson, Paul N.
2009-01-01
Using desktop, computer-simulated virtual environments (VEs), the authors conducted 5 experiments to investigate blocking of learning about a goal location based on Shape B as a consequence of preliminary training to locate that goal using Shape A. The shapes were large 2-dimensional horizontal figures on the ground. Blocking of spatial learning…
Design and Functionality of the Graphical Interactive Narrative (Gin) System Version 0.2
2012-08-01
System. The purpose of the Gin system is to increase the interactivity and sense of agency for human subjects in virtual environments (VEs) used for...tractability of scenario development while providing the user with an increased sense of agency by allowing them to control their own navigation
Software Architecture for a Virtual Environment for Nano Scale Assembly (VENSA).
Lee, Yong-Gu; Lyons, Kevin W; Feng, Shaw C
2004-01-01
A Virtual Environment (VE) uses multiple computer-generated media to let a user experience situations that are temporally and spatially prohibiting. The information flow between the user and the VE is bidirectional and the user can influence the environment. The software development of a VE requires orchestrating multiple peripherals and computers in a synchronized way in real time. Although a multitude of useful software components for VEs exists, many of these are packaged within a complex framework and can not be used separately. In this paper, an architecture is presented which is designed to let multiple frameworks work together while being shielded from the application program. This architecture, which is called the Virtual Environment for Nano Scale Assembly (VENSA), has been constructed for interfacing with an optical tweezers instrument for nanotechnology development. However, this approach can be generalized for most virtual environments. Through the use of VENSA, the programmer can rely on existing solutions and concentrate more on the application software design.
Software Architecture for a Virtual Environment for Nano Scale Assembly (VENSA)
Lee, Yong-Gu; Lyons, Kevin W.; Feng, Shaw C.
2004-01-01
A Virtual Environment (VE) uses multiple computer-generated media to let a user experience situations that are temporally and spatially prohibiting. The information flow between the user and the VE is bidirectional and the user can influence the environment. The software development of a VE requires orchestrating multiple peripherals and computers in a synchronized way in real time. Although a multitude of useful software components for VEs exists, many of these are packaged within a complex framework and can not be used separately. In this paper, an architecture is presented which is designed to let multiple frameworks work together while being shielded from the application program. This architecture, which is called the Virtual Environment for Nano Scale Assembly (VENSA), has been constructed for interfacing with an optical tweezers instrument for nanotechnology development. However, this approach can be generalized for most virtual environments. Through the use of VENSA, the programmer can rely on existing solutions and concentrate more on the application software design. PMID:27366610
Cue exposure treatment in a virtual environment to reduce nicotine craving: a functional MRI study.
Moon, Jiyoon; Lee, Jang-Han
2009-02-01
Smokers show an increase in cue reactivity during exposure to smoking-related cues. CET aims at extinguishing cue reactivity by repeated presentation of substance-related cues and has been claimed a potentially effective method of treating addictive behaviors, including cigarette smoking. We applied CET to eight late-adolescent smokers in virtual environments (VEs). When comparing pre-CET regions to those of post-CET, the inferior frontal gyrus and superior frontal gyrus were detected. These regions are consistent with previous studies of activated brain regions related to nicotine craving, and VE-CET seems to be an effective method of treating nicotine craving.
Building a Virtual Environment for Diabetes Self-Management Education and Support
Johnson, Constance; Feenan, Kevin; Setliff, Glenn; Pereira, Katherine; Hassell, Nancy; Beresford, Henry F.; Epps, Shelly; Nicollerat, Janet; Tatum, William; Feinglos, Mark; Vorderstrasse, Allison
2015-01-01
The authors developed an immersive diabetes community to provide diabetes self-management education and support for adults with type 2 diabetes. In this article the authors describe the procedures used to develop this virtual environment (VE). Second Life Impacts Diabetes Education & Self-Management (SLIDES), the VE for our diabetes community was built in Second Life. Social Cognitive Theory, behavioral principles and key aspects of virtual environments related to usability were applied in the development in this VE. Collaboration between researchers, clinicians and information technology (IT) specialists occurred throughout the development process. An interactive community was successfully built and utilized to provide diabetes self-management education and support. VEs for health applications may be innovative and enticing, yet it must be kept in mind that there are substantial effort, expertise, and usability factors that must be considered in the development of these environments for health care consumers. PMID:25699133
Korocsec, D; Holobar, A; Divjak, M; Zazula, D
2005-12-01
Medicine is a difficult thing to learn. Experimenting with real patients should not be the only option; simulation deserves a special attention here. Virtual Reality Modelling Language (VRML) as a tool for building virtual objects and scenes has a good record of educational applications in medicine, especially for static and animated visualisations of body parts and organs. However, to create computer simulations resembling situations in real environments the required level of interactivity and dynamics is difficult to achieve. In the present paper we describe some approaches and techniques which we used to push the limits of the current VRML technology further toward dynamic 3D representation of virtual environments (VEs). Our demonstration is based on the implementation of a virtual baby model, whose vital signs can be controlled from an external Java application. The main contributions of this work are: (a) outline and evaluation of the three-level VRML/Java implementation of the dynamic virtual environment, (b) proposal for a modified VRML Timesensor node, which greatly improves the overall control of system performance, and (c) architecture of the prototype distributed virtual environment for training in neonatal resuscitation comprising the interactive virtual newborn, active bedside monitor for vital signs and full 3D representation of the surgery room.
Toet, Alexander; van Schaik, Martin; Theunissen, Nicolet C. M.
2013-01-01
Background Desktop virtual environments (VEs) are increasingly deployed to study the effects of environmental qualities and interventions on human behavior and safety related concerns in built environments. For these applications it is essential that users appraise the affective qualities of the VE similar to those of its real world counterpart. Previous studies have shown that factors like simulated lighting, sound and dynamic elements all contribute to the affective appraisal of a desktop VE. Since ambient odor is known to affect the affective appraisal of real environments, and has been shown to increase the sense of presence in immersive VEs, it may also be an effective tool to tune the affective appraisal of desktop VEs. This study investigated if exposure to ambient odor can modulate the affective appraisal of a desktop VE with signs of public disorder. Method Participants explored a desktop VE representing a suburban neighborhood with signs of public disorder (neglect, vandalism and crime), while being exposed to either room air or subliminal levels of unpleasant (tar) or pleasant (cut grass) ambient odor. Whenever they encountered signs of disorder they reported their safety related concerns and associated affective feelings. Results Signs of crime in the desktop VE were associated with negative affective feelings and concerns for personal safety and personal property. However, there was no significant difference between reported safety related concerns and affective connotations in the control (no-odor) and in each of the two ambient odor conditions. Conclusion Ambient odor did not affect safety related concerns and affective connotations associated with signs of disorder in the desktop VE. Thus, semantic congruency between ambient odor and a desktop VE may not be sufficient to influence its affective appraisal, and a more realistic simulation in which simulated objects appear to emit scents may be required to achieve this goal. PMID:24250810
Lewinski, Allison A; Anderson, Ruth A; Vorderstrasse, Allison A; Fisher, Edwin B; Pan, Wei; Johnson, Constance M
2018-02-21
Virtual environments (VEs) facilitate interaction and support among individuals with chronic illness, yet the characteristics of these VE interactions remain unknown. The objective of this study was to describe social interaction and support among individuals with type 2 diabetes (T2D) who interacted in a VE. Data included VE-mediated synchronous conversations and text-chat and asynchronous emails and discussion board posts from a study that facilitated interaction among individuals with T2D and diabetes educators (N=24) in 2 types of sessions: education and support. VE interactions consisted of communication techniques (how individuals interact in the VE), expressions of self-management (T2D-related topics), depth (personalization of topics), and breadth (number of topics discussed). Individuals exchanged support more often in the education (723/1170, 61.79%) than in the support (406/1170, 34.70%) sessions or outside session time (41/1170, 3.50%). Of all support exchanges, 535/1170 (45.73%) were informational, 377/1170 (32.22%) were emotional, 217/1170 (18.55%) were appraisal, and 41/1170 (3.50%) were instrumental. When comparing session types, education sessions predominately provided informational support (357/723, 49.4%), and the support sessions predominately provided emotional (159/406, 39.2%) and informational (159/406, 39.2%) support. VE-mediated interactions resemble those in face-to-face environments, as individuals in VEs engage in bidirectional exchanges with others to obtain self-management education and support. Similar to face-to-face environments, individuals in the VE revealed personal information, sought information, and exchanged support during the moderated education sessions and unstructured support sessions. With this versatility, VEs are able to contribute substantially to support for those with diabetes and, very likely, other chronic diseases. ©Allison A Lewinski, Ruth A Anderson, Allison A Vorderstrasse, Edwin B Fisher, Wei Pan, Constance M Johnson. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 21.02.2018.
Toet, Alexander; van Schaik, Martin; Theunissen, Nicolet C M
2013-01-01
Desktop virtual environments (VEs) are increasingly deployed to study the effects of environmental qualities and interventions on human behavior and safety related concerns in built environments. For these applications it is essential that users appraise the affective qualities of the VE similar to those of its real world counterpart. Previous studies have shown that factors like simulated lighting, sound and dynamic elements all contribute to the affective appraisal of a desktop VE. Since ambient odor is known to affect the affective appraisal of real environments, and has been shown to increase the sense of presence in immersive VEs, it may also be an effective tool to tune the affective appraisal of desktop VEs. This study investigated if exposure to ambient odor can modulate the affective appraisal of a desktop VE with signs of public disorder. Participants explored a desktop VE representing a suburban neighborhood with signs of public disorder (neglect, vandalism and crime), while being exposed to either room air or subliminal levels of unpleasant (tar) or pleasant (cut grass) ambient odor. Whenever they encountered signs of disorder they reported their safety related concerns and associated affective feelings. Signs of crime in the desktop VE were associated with negative affective feelings and concerns for personal safety and personal property. However, there was no significant difference between reported safety related concerns and affective connotations in the control (no-odor) and in each of the two ambient odor conditions. Ambient odor did not affect safety related concerns and affective connotations associated with signs of disorder in the desktop VE. Thus, semantic congruency between ambient odor and a desktop VE may not be sufficient to influence its affective appraisal, and a more realistic simulation in which simulated objects appear to emit scents may be required to achieve this goal.
MERIANS, A. S.; TUNIK, E.; FLUET, G. G.; QIU, Q.; ADAMOVICH, S. V.
2017-01-01
Aim Upper-extremity interventions for hemiparesis are a challenging aspect of stroke rehabilitation. Purpose of this paper is to report the feasibility of using virtual environments (VEs) in combination with robotics to assist recovery of hand-arm function and to present preliminary data demonstrating the potential of using sensory manipulations in VE to drive activation in targeted neural regions. Methods We trained 8 subjects for 8 three hour sessions using a library of complex VE’s integrated with robots, comparing training arm and hand separately to training arm and hand together. Instrumented gloves and hand exoskeleton were used for hand tracking and haptic effects. Haptic Master robotic arm was used for arm tracking and generating three-dimensional haptic VEs. To investigate the use of manipulations in VE to drive neural activations, we created a “virtual mirror” that subjects used while performing a unimanual task. Cortical activation was measured with functional MRI (fMRI) and transcranial magnetic stimulation. Results Both groups showed improvement in kinematics and measures of real-world function. The group trained using their arm and hand together showed greater improvement. In a stroke subject, fMRI data suggested virtual mirror feedback could activate the sensorimotor cortex contralateral to the reflected hand (ipsilateral to the moving hand) thus recruiting the lesioned hemisphere. Conclusion Gaming simulations interfaced with robotic devices provide a training medium that can modify movement patterns. In addition to showing that our VE therapies can optimize behavioral performance, we show preliminary evidence to support the potential of using specific sensory manipulations to selectively recruit targeted neural circuits. PMID:19158659
Ramírez-Fernández, Cristina; Morán, Alberto L; García-Canseco, Eloísa; Gómez-Montalvo, Jorge R
2017-03-23
1) To enhance the content of an ontology for designing virtual environments (VEs) for upper limb motor rehabilitation of stroke patients according to the suggestions and comments of rehabilitation specialists and software developers, 2) to characterize the perceived importance level of the ontology, 3) to determine the perceived usefulness of the ontology, and 4) to identify the safety characteristics of the ontology for VEs design according to the rehabilitation specialists. Using two semi-structured Web questionnaires, we asked six rehabilitation specialists and six software developers to provide us with their perception regarding the level of importance and the usability of the ontology. From their responses we have identified themes related to perceived and required safety characteristics of the ontology. Significant differences in the importance level were obtained for the Stroke Disability, VE Configuration, Outcome Measures, and Safety Calibration classes, which were perceived as highly important by rehabilitation specialists. Regarding usability, the ontology was perceived by both groups with high usefulness, ease of use, learnability and intention of use. Concerning the thematic analysis of recommendations, eight topics for safety characteristics of the ontology were identified: adjustment of therapy strategies; selection and delimitation of movements; selection and proper calibration of the interaction device; proper selection of measuring instruments; gradual modification of the difficulty of the exercise; adaptability and variability of therapy exercises; feedback according to the capabilities of the patient; and real-time support for exercise training. The rehabilitation specialists and software developers confirmed the importance of the information contained in the ontology regarding motor rehabilitation of the upper limb. Their recommendations highlight the safety features and the advantages of the ontology as a guide for the effective design of VEs.
Kinematic/Dynamic Characteristics for Visual and Kinesthetic Virtual Environments
NASA Technical Reports Server (NTRS)
Bortolussi, Michael R. (Compiler); Adelstein, B. D.; Gold, Miriam
1996-01-01
Work was carried out on two topics of principal importance to current progress in virtual environment research at NASA Ames and elsewhere. The first topic was directed at maximizing the temporal dynamic response of visually presented Virtual Environments (VEs) through reorganization and optimization of system hardware and software. The final results of this portion of the work was a VE system in the Advanced Display and Spatial Perception Laboratory at NASA Ames capable of updating at 60 Hz (the maximum hardware refresh rate) with latencies approaching 30 msec. In the course of achieving this system performance, specialized hardware and software tools for measurement of VE latency and analytic models correlating update rate and latency for different system configurations were developed. The second area of activity was the preliminary development and analysis of a novel kinematic architecture for three Degree Of Freedom (DOF) haptic interfaces--devices that provide force feedback for manipulative interaction with virtual and remote environments. An invention disclosure was filed on this work and a patent application is being pursued by NASA Ames. Activities in these two areas are expanded upon below.
Simulating Navigation with Virtual 3d Geovisualizations - a Focus on Memory Related Factors
NASA Astrophysics Data System (ADS)
Lokka, I.; Çöltekin, A.
2016-06-01
The use of virtual environments (VE) for navigation-related studies, such as spatial cognition and path retrieval has been widely adopted in cognitive psychology and related fields. What motivates the use of VEs for such studies is that, as opposed to real-world, we can control for the confounding variables in simulated VEs. When simulating a geographic environment as a virtual world with the intention to train navigational memory in humans, an effective and efficient visual design is important to facilitate the amount of recall. However, it is not yet clear what amount of information should be included in such visual designs intended to facilitate remembering: there can be too little or too much of it. Besides the amount of information or level of detail, the types of visual features (`elements' in a visual scene) that should be included in the representations to create memorable scenes and paths must be defined. We analyzed the literature in cognitive psychology, geovisualization and information visualization, and identified the key factors for studying and evaluating geovisualization designs for their function to support and strengthen human navigational memory. The key factors we identified are: i) the individual abilities and age of the users, ii) the level of realism (LOR) included in the representations and iii) the context in which the navigation is performed, thus specific tasks within a case scenario. Here we present a concise literature review and our conceptual development for follow-up experiments.
Visual Perspective and Feedback Guidance for VR Free-Throw Training.
Covaci, Alexandra; Olivier, Anne-Hélène; Multon, Franck
2015-01-01
Accurate distance perception and natural interactions are mandatory conditions when training precision aiming tasks in VR. However, many factors specific to virtual environments (VEs) lead to differences in the way users execute a motor task in VR versus the real world. To investigate these differences, the authors performed a study on basketball beginners' free-throw performance in VEs under different visual conditions. Although the success rate is not statistically different, some adaptations occurred in the way the users performed the task, depending on the visual conditions. In the third-person perspective visual condition, the release parameters indicate that the users more accurately estimated distance to target. Adding visual guidance information (gradual depth information showing the ideal ball trajectory) also led to more natural motor behavior. The final aim of this study was to develop a reliable basketball free-throw training system in VEs, so the authors compared beginners' performances in VR with experts' models of performance. Their results show that most of the performance variables tended to evolve closer to the experts' performance during the training in the VE.
Magdalon, Eliane C; Michaelsen, Stella M; Quevedo, Antonio A; Levin, Mindy F
2011-09-01
Virtual reality (VR) technology is being used with increasing frequency as a training medium for motor rehabilitation. However, before addressing training effectiveness in virtual environments (VEs), it is necessary to identify if movements made in such environments are kinematically similar to those made in physical environments (PEs) and the effect of provision of haptic feedback on these movement patterns. These questions are important since reach-to-grasp movements may be inaccurate when visual or haptic feedback is altered or absent. Our goal was to compare kinematics of reaching and grasping movements to three objects performed in an immersive three-dimensional (3D) VE with haptic feedback (cyberglove/grasp system) viewed through a head-mounted display to those made in an equivalent physical environment (PE). We also compared movements in PE made with and without wearing the cyberglove/grasp haptic feedback system. Ten healthy subjects (8 women, 62.1±8.8years) reached and grasped objects requiring 3 different grasp types (can, diameter 65.6mm, cylindrical grasp; screwdriver, diameter 31.6mm, power grasp; pen, diameter 7.5mm, precision grasp) in PE and visually similar virtual objects in VE. Temporal and spatial arm and trunk kinematics were analyzed. Movements were slower and grip apertures were wider when wearing the glove in both the PE and the VE compared to movements made in the PE without the glove. When wearing the glove, subjects used similar reaching trajectories in both environments, preserved the coordination between reaching and grasping and scaled grip aperture to object size for the larger object (cylindrical grasp). However, in VE compared to PE, movements were slower and had longer deceleration times, elbow extension was greater when reaching to the smallest object and apertures were wider for the power and precision grip tasks. Overall, the differences in spatial and temporal kinematics of movements between environments were greater than those due only to wearing the cyberglove/grasp system. Differences in movement kinematics due to the viewing environment were likely due to a lack of prior experience with the virtual environment, an uncertainty of object location and the restricted field-of-view when wearing the head-mounted display. The results can be used to inform the design and disposition of objects within 3D VEs for the study of the control of prehension and for upper limb rehabilitation. Copyright © 2011 Elsevier B.V. All rights reserved.
Direct manipulation of virtual objects
NASA Astrophysics Data System (ADS)
Nguyen, Long K.
Interacting with a Virtual Environment (VE) generally requires the user to correctly perceive the relative position and orientation of virtual objects. For applications requiring interaction in personal space, the user may also need to accurately judge the position of the virtual object relative to that of a real object, for example, a virtual button and the user's real hand. This is difficult since VEs generally only provide a subset of the cues experienced in the real world. Complicating matters further, VEs presented by currently available visual displays may be inaccurate or distorted due to technological limitations. Fundamental physiological and psychological aspects of vision as they pertain to the task of object manipulation were thoroughly reviewed. Other sensory modalities -- proprioception, haptics, and audition -- and their cross-interactions with each other and with vision are briefly discussed. Visual display technologies, the primary component of any VE, were canvassed and compared. Current applications and research were gathered and categorized by different VE types and object interaction techniques. While object interaction research abounds in the literature, pockets of research gaps remain. Direct, dexterous, manual interaction with virtual objects in Mixed Reality (MR), where the real, seen hand accurately and effectively interacts with virtual objects, has not yet been fully quantified. An experimental test bed was designed to provide the highest accuracy attainable for salient visual cues in personal space. Optical alignment and user calibration were carefully performed. The test bed accommodated the full continuum of VE types and sensory modalities for comprehensive comparison studies. Experimental designs included two sets, each measuring depth perception and object interaction. The first set addressed the extreme end points of the Reality-Virtuality (R-V) continuum -- Immersive Virtual Environment (IVE) and Reality Environment (RE). This validated, linked, and extended several previous research findings, using one common test bed and participant pool. The results provided a proven method and solid reference points for further research. The second set of experiments leveraged the first to explore the full R-V spectrum and included additional, relevant sensory modalities. It consisted of two full-factorial experiments providing for rich data and key insights into the effect of each type of environment and each modality on accuracy and timeliness of virtual object interaction. The empirical results clearly showed that mean depth perception error in personal space was less than four millimeters whether the stimuli presented were real, virtual, or mixed. Likewise, mean error for the simple task of pushing a button was less than four millimeters whether the button was real or virtual. Mean task completion time was less than one second. Key to the high accuracy and quick task performance time observed was the correct presentation of the visual cues, including occlusion, stereoscopy, accommodation, and convergence. With performance results already near optimal level with accurate visual cues presented, adding proprioception, audio, and haptic cues did not significantly improve performance. Recommendations for future research include enhancement of the visual display and further experiments with more complex tasks and additional control variables.
Review of Enabling Technologies to Facilitate Secure Compute Customization
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aderholdt, Ferrol; Caldwell, Blake A; Hicks, Susan Elaine
High performance computing environments are often used for a wide variety of workloads ranging from simulation, data transformation and analysis, and complex workflows to name just a few. These systems may process data for a variety of users, often requiring strong separation between job allocations. There are many challenges to establishing these secure enclaves within the shared infrastructure of high-performance computing (HPC) environments. The isolation mechanisms in the system software are the basic building blocks for enabling secure compute enclaves. There are a variety of approaches and the focus of this report is to review the different virtualization technologies thatmore » facilitate the creation of secure compute enclaves. The report reviews current operating system (OS) protection mechanisms and modern virtualization technologies to better understand the performance/isolation properties. We also examine the feasibility of running ``virtualized'' computing resources as non-privileged users, and providing controlled administrative permissions for standard users running within a virtualized context. Our examination includes technologies such as Linux containers (LXC [32], Docker [15]) and full virtualization (KVM [26], Xen [5]). We categorize these different approaches to virtualization into two broad groups: OS-level virtualization and system-level virtualization. The OS-level virtualization uses containers to allow a single OS kernel to be partitioned to create Virtual Environments (VE), e.g., LXC. The resources within the host's kernel are only virtualized in the sense of separate namespaces. In contrast, system-level virtualization uses hypervisors to manage multiple OS kernels and virtualize the physical resources (hardware) to create Virtual Machines (VM), e.g., Xen, KVM. This terminology of VE and VM, detailed in Section 2, is used throughout the report to distinguish between the two different approaches to providing virtualized execution environments. As part of our technology review we analyzed several current virtualization solutions to assess their vulnerabilities. This included a review of common vulnerabilities and exposures (CVEs) for Xen, KVM, LXC and Docker to gauge their susceptibility to different attacks. The complete details are provided in Section 5 on page 33. Based on this review we concluded that system-level virtualization solutions have many more vulnerabilities than OS level virtualization solutions. As such, security mechanisms like sVirt (Section 3.3) should be considered when using system-level virtualization solutions in order to protect the host against exploits. The majority of vulnerabilities related to KVM, LXC, and Docker are in specific regions of the system. Therefore, future "zero day attacks" are likely to be in the same regions, which suggests that protecting these areas can simplify the protection of the host and maintain the isolation between users. The evaluations of virtualization technologies done thus far are discussed in Section 4. This includes experiments with 'user' namespaces in VEs, which provides the ability to isolate user privileges and allow a user to run with different UIDs within the container while mapping them to non-privileged UIDs in the host. We have identified Linux namespaces as a promising mechanism to isolate shared resources, while maintaining good performance. In Section 4.1 we describe our tests with LXC as a non-root user and leveraging namespaces to control UID/GID mappings and support controlled sharing of parallel file-systems. We highlight several of these namespace capabilities in Section 6.2.3. The other evaluations that were performed during this initial phase of work provide baseline performance data for comparing VEs and VMs to purely native execution. In Section 4.2 we performed tests using the High-Performance Computing Conjugate Gradient (HPCCG) benchmark to establish baseline performance for a scientific application when run on the Native (host) machine in contrast with execution under Docker and KVM. Our tests verified prior studies showing roughly 2-4% overheads in application execution time & MFlops when running in hypervisor-base environments (VMs) as compared to near native performance with VEs. For more details, see Figures 4.5 (page 28), 4.6 (page 28), and 4.7 (page 29). Additionally, in Section 4.3 we include network measurements for TCP bandwidth performance over the 10GigE interface in our testbed. The Native and Docker based tests achieved >= ~9Gbits/sec, while the KVM configuration only achieved 2.5Gbits/sec (Table 4.6 on page 32). This may be a configuration issue with our KVM installation, and is a point for further testing as we refine the network settings in the testbed. The initial network tests were done using a bridged networking configuration. The report outline is as follows: - Section 1 introduces the report and clarifies the scope of the proj...« less
Gender issues in the use of virtual environments.
Larson, P; Rizzo, A A; Buckwalter, J G; Van Rooyen, A; Kratz, K; Neumann, U; Kesselman, C; Thiebaux, M; Van Der Zaag, C
1999-01-01
Gender differences in cognitive and behavioral performance have been reported throughout the psychological literature. Consequently, gender differences should be considered and controlled for when cognitive research is conducted in virtual environments (VEs). These variables may include gender-related differences in cognitive performance, susceptibility for cybersickness, and the impact of sex hormones on cognition. Such issues are addressed in the context of a recent VE study of the visuospatial ability referred to as mental rotation. The Mental Rotation Test (MRT), a paper and pencil measure, has been shown to produce one of the largest gender differences in the cognitive literature. The outcomes of the MRT are in favor of males. However, results reported from a Virtual Reality Spatial Rotation (VRSR) test demonstrate no gender differences when subjects were able to manually manipulate the stimuli in a VE. Further analysis uncovers gender differences in the patterns of associations between verbal and spatial tasks and performance on VRSR. Results are discussed in terms of dimensionality factors and hemispheric lateralization.
Adamovich, S.V.; August, K.; Merians, A.; Tunik, E.
2017-01-01
Purpose Emerging evidence shows that interactive virtual environments (VEs) may be a promising tool for studying sensorimotor processes and for rehabilitation. However, the potential of VEs to recruit action observation-execution neural networks is largely unknown. For the first time, a functional MRI-compatible virtual reality system (VR) has been developed to provide a window into studying brain-behavior interactions. This system is capable of measuring the complex span of hand-finger movements and simultaneously streaming this kinematic data to control the motion of representations of human hands in virtual reality. Methods In a blocked fMRI design, thirteen healthy subjects observed, with the intent to imitate (OTI), finger sequences performed by the virtual hand avatar seen in 1st person perspective and animated by pre-recorded kinematic data. Following this, subjects imitated the observed sequence while viewing the virtual hand avatar animated by their own movement in real-time. These blocks were interleaved with rest periods during which subjects viewed static virtual hand avatars and control trials in which the avatars were replaced with moving non-anthropomorphic objects. Results We show three main findings. First, both observation with intent to imitate and imitation with real-time virtual avatar feedback, were associated with activation in a distributed frontoparietal network typically recruited for observation and execution of real-world actions. Second, we noted a time-variant increase in activation in the left insular cortex for observation with intent to imitate actions performed by the virtual avatar. Third, imitation with virtual avatar feedback (relative to the control condition) was associated with a localized recruitment of the angular gyrus, precuneus, and extrastriate body area, regions which are (along with insular cortex) associated with the sense of agency. Conclusions Our data suggest that the virtual hand avatars may have served as disembodied training tools in the observation condition and as embodied “extensions” of the subject’s own body (pseudo-tools) in the imitation. These data advance our understanding of the brain-behavior interactions when performing actions in VE and have implications in the development of observation- and imitation-based VR rehabilitation paradigms. PMID:19531876
Cybersickness Following Repeated Exposure to DOME and HMD Virtual Environments
NASA Technical Reports Server (NTRS)
Taylor, Laura C.; Harm, Deborah L.; Kennedy, Robert S.; Reschke, Millard F.; Loftin, R. Bowen
2011-01-01
Virtual environments (VE) offer unique training opportunities, including training astronauts to preadapt them to the novel sensory conditions of microgravity. However, one unresolved issue with VE use is the occurrence of cybersickness during and following exposure to VE systems. Most individuals adapt and become less ill with repeated interaction with VEs. The goal of this investigation was to compare motion sickness symptoms (MSS) produced by dome and head-mounted (HMD) displays and to examine the effects of repeated exposures on MSS. Sixty-one subjects participated in the study. Three experimental sessions were performed each separated by one day. The subjects performed a navigation and pick and place task in either a dome or HMD VE. MSS were measured using a Simulator Sickness Questionnaire before, immediately after, and at 1, 2, 4 and 6 hours following exposure to the VEs. MSS data were normalized by calculating the natural log of each score and an analysis of variance was performed. We observed significant main effects for day and time and a significant day by time interaction for total sickness and for each of the subscales, nausea, oculomotor and disorientation. However, there was no significant main effect for device. In conclusion, subjects reported a large increase in MSS immediately following exposure to both the HMD and dome, followed by a rapid recovery across time. Sickness severity also decreased over days, which suggests that subjects become dual-adapted over time making VE training a viable pre-flight countermeasure for space motion sickness.
Liu, Cheng-Li
2009-05-01
Only a few studies in the literature have focused on the effects of age on virtual environment (VE) sickness susceptibility and even less research was carried out focusing on the elderly. In general, the elderly usually browse VEs on a thin film transistor liquid crystal display (TFT-LCD) at home or somewhere, not a head-mounted display (HMD). While the TFT-LCD is used to present VEs, this set-up does not physically enclose the user. Therefore, this study investigated the factors that contribute to cybersickness among the elderly when immersed into a VE on TFT-LCD, including exposure durations, navigation rotating speeds and angle of inclination. Participants were elderly, with an average age of 69.5 years. The results of the first experiment showed that the rate of simulator sickness questionnaire (SSQ) scores increases significantly with navigational rotating speed and duration of exposure. However, the experimental data also showed that the rate of SSQ scores does not increase with the increase in angle of inclination. In applying these findings, the neuro-fuzzy technology was used to develop a neuro-fuzzy cybersickness-warning system integrating fuzzy logic reasoning and neural network learning. The contributing factors were navigational rotating speed and duration of exposure. The results of the second experiment showed that the proposed system can efficiently determine the level of cybersickness based on the associated subjective sickness estimates and combat cybersickness due to long exposure to a VE.
Predictive Compensator Optimization for Head Tracking Lag in Virtual Environments
NASA Technical Reports Server (NTRS)
Adelstein, Barnard D.; Jung, Jae Y.; Ellis, Stephen R.
2001-01-01
We examined the perceptual impact of plant noise parameterization for Kalman Filter predictive compensation of time delays intrinsic to head tracked virtual environments (VEs). Subjects were tested in their ability to discriminate between the VE system's minimum latency and conditions in which artificially added latency was then predictively compensated back to the system minimum. Two head tracking predictors were parameterized off-line according to cost functions that minimized prediction errors in (1) rotation, and (2) rotation projected into translational displacement with emphasis on higher frequency human operator noise. These predictors were compared with a parameterization obtained from the VE literature for cost function (1). Results from 12 subjects showed that both parameterization type and amount of compensated latency affected discrimination. Analysis of the head motion used in the parameterizations and the subsequent discriminability results suggest that higher frequency predictor artifacts are contributory cues for discriminating the presence of predictive compensation.
High sensitivity to multisensory conflicts in agoraphobia exhibited by virtual reality.
Viaud-Delmon, Isabelle; Warusfel, Olivier; Seguelas, Angeline; Rio, Emmanuel; Jouvent, Roland
2006-10-01
The primary aim of this study was to evaluate the effect of auditory feedback in a VR system planned for clinical use and to address the different factors that should be taken into account in building a bimodal virtual environment (VE). We conducted an experiment in which we assessed spatial performances in agoraphobic patients and normal subjects comparing two kinds of VEs, visual alone (Vis) and auditory-visual (AVis), during separate sessions. Subjects were equipped with a head-mounted display coupled with an electromagnetic sensor system and immersed in a virtual town. Their task was to locate different landmarks and become familiar with the town. In the AVis condition subjects were equipped with the head-mounted display and headphones, which delivered a soundscape updated in real-time according to their movement in the virtual town. While general performances remained comparable across the conditions, the reported feeling of immersion was more compelling in the AVis environment. However, patients exhibited more cybersickness symptoms in this condition. The result of this study points to the multisensory integration deficit of agoraphobic patients and underline the need for further research on multimodal VR systems for clinical use.
Feinglos, Mark; Pereira, Katherine; Hassell, Nancy; Blascovich, Jim; Nicollerat, Janet; Beresford, Henry F; Levy, Janet; Vorderstrasse, Allison
2014-01-01
Background Innovative interventions that empower patients in diabetes self-management (DSM) are needed to provide accessible, sustainable, cost-effective patient education and support that surpass current noninteractive interventions. Skills acquired in digital virtual environments (VEs) affect behaviors in the physical world. Some VEs are programmed as real-time three-dimensional representations of various settings via the Internet. For this research, a theoretically grounded VE that facilitates DSM was developed and pilot tested. It offered weekly synchronous DSM education classes, group meetings, and social networking in a community in which participants practiced real world skills such as grocery shopping, exercising, and dining out, allowing for interactive knowledge application. The VE was available 24/7 on the Internet, minimizing access barriers. Objective The objective of this study was to evaluate the feasibility and efficacy of participation in a VE for DSM education and support. Methods This study utilized a single group, pre-mid-post measure design. At 0, 3, and 6 months, we assessed participants’ perceived VE usability and usefulness, self-efficacy, diabetes self-management behaviors, perceived social support, and diabetes knowledge using validated survey measures; and we recorded metabolic indicators (HbA1c, BP, BMI). Process data were continuously collected in the VE (log-ins, voice recordings, locations visited, objects interacted with, and movement). Data analysis included descriptive statistics, t tests to evaluate changes in mediators and outcomes over time, and depiction of utilization and movement data. Results We enrolled 20 participants (13/20, 65% white, 7/20, 35% black), with an age range of 39-72 years (mean age, 54 years) and diabetes duration from 3 months to 25 years. At baseline, 95% (18/19) and 79% (15/19) of participants rated usefulness and ease of use as high on validated surveys with no significant changes at 3 or 6 months. Participants logged into the site a mean of 2.5 hours/week over the course of 6 months. High DSM class attendance was reflected by the largest percentage of time spent in the classroom (48.6%). Self-efficacy, social support, and foot care showed significant improvement (P<.05). There were improvement trends in clinical outcomes that were clinically meaningful but did not reach statistical significance given the small sample size. Conclusions Because relatively little is known about usability, acceptability, and efficacy of health interventions in VEs, this study constitutes an important, innovative first step in exploring the potential of VEs for facilitating DSM. The preliminary data suggest that VEs provide a feasible and useful platform for patients and educators that affects self-management and related mediators. Flexible access to both synchronous and asynchronous diabetes education, skill building activities, and support from a home computer remove barriers to attending clinic-based meetings. This program has potential for improving DSM in an easily disseminated alternative model. PMID:24713420
Johnson, Constance; Feinglos, Mark; Pereira, Katherine; Hassell, Nancy; Blascovich, Jim; Nicollerat, Janet; Beresford, Henry F; Levy, Janet; Vorderstrasse, Allison
2014-04-08
Innovative interventions that empower patients in diabetes self-management (DSM) are needed to provide accessible, sustainable, cost-effective patient education and support that surpass current noninteractive interventions. Skills acquired in digital virtual environments (VEs) affect behaviors in the physical world. Some VEs are programmed as real-time three-dimensional representations of various settings via the Internet. For this research, a theoretically grounded VE that facilitates DSM was developed and pilot tested. It offered weekly synchronous DSM education classes, group meetings, and social networking in a community in which participants practiced real world skills such as grocery shopping, exercising, and dining out, allowing for interactive knowledge application. The VE was available 24/7 on the Internet, minimizing access barriers. The objective of this study was to evaluate the feasibility and efficacy of participation in a VE for DSM education and support. This study utilized a single group, pre-mid-post measure design. At 0, 3, and 6 months, we assessed participants' perceived VE usability and usefulness, self-efficacy, diabetes self-management behaviors, perceived social support, and diabetes knowledge using validated survey measures; and we recorded metabolic indicators (HbA1c, BP, BMI). Process data were continuously collected in the VE (log-ins, voice recordings, locations visited, objects interacted with, and movement). Data analysis included descriptive statistics, t tests to evaluate changes in mediators and outcomes over time, and depiction of utilization and movement data. We enrolled 20 participants (13/20, 65% white, 7/20, 35% black), with an age range of 39-72 years (mean age, 54 years) and diabetes duration from 3 months to 25 years. At baseline, 95% (18/19) and 79% (15/19) of participants rated usefulness and ease of use as high on validated surveys with no significant changes at 3 or 6 months. Participants logged into the site a mean of 2.5 hours/week over the course of 6 months. High DSM class attendance was reflected by the largest percentage of time spent in the classroom (48.6%). Self-efficacy, social support, and foot care showed significant improvement (P<.05). There were improvement trends in clinical outcomes that were clinically meaningful but did not reach statistical significance given the small sample size. Because relatively little is known about usability, acceptability, and efficacy of health interventions in VEs, this study constitutes an important, innovative first step in exploring the potential of VEs for facilitating DSM. The preliminary data suggest that VEs provide a feasible and useful platform for patients and educators that affects self-management and related mediators. Flexible access to both synchronous and asynchronous diabetes education, skill building activities, and support from a home computer remove barriers to attending clinic-based meetings. This program has potential for improving DSM in an easily disseminated alternative model.
Design of a 3D Navigation Technique Supporting VR Interaction
NASA Astrophysics Data System (ADS)
Boudoin, Pierre; Otmane, Samir; Mallem, Malik
2008-06-01
Multimodality is a powerful paradigm to increase the realness and the easiness of the interaction in Virtual Environments (VEs). In particular, the search for new metaphors and techniques for 3D interaction adapted to the navigation task is an important stage for the realization of future 3D interaction systems that support multimodality, in order to increase efficiency and usability. In this paper we propose a new multimodal 3D interaction model called Fly Over. This model is especially devoted to the navigation task. We present a qualitative comparison between Fly Over and a classical navigation technique called gaze-directed steering. The results from preliminary evaluation on the IBISC semi-immersive Virtual Reality/Augmented Realty EVR@ platform show that Fly Over is a user friendly and efficient navigation technique.
Malešević, Jovana; Štrbac, Matija; Isaković, Milica; Kojić, Vladimir; Konstantinović, Ljubica; Vidaković, Aleksandra; Dedijer Dujović, Suzana; Kostić, Miloš; Keller, Thierry
2017-11-01
The goal of this study was to investigate surface motor activation zones and their temporal variability using an advanced multi-pad functional electrical stimulation system. With this system motor responses are elicited through concurrent activation of electrode matrix pads collectively termed "virtual electrodes" (VEs) with appropriate stimulation parameters. We observed VEs used to produce selective wrist, finger, and thumb extension movements in 20 therapy sessions of 12 hemiplegic stroke patients. The VEs which produce these three selective movements were created manually on the ergonomic multi-pad electrode by experienced clinicians based on visual inspection of the muscle responses. Individual results indicated that changes in VE configuration were required each session for all patients and that overlap in joint movements was evident between some VEs. However, by analyzing group data, we defined the probability distribution over the electrode surface for the three VEs of interest. Furthermore, through Bayesian logic we obtained preferred stimulation zones that are in accordance with our previously reported heuristically obtained results. We have also analyzed the number of active pads and stimulation amplitudes for these three VEs. Presented results provide a basis for an automated electrode calibration algorithm built on a priori knowledge or the starting point for manual selection of stimulation points. © 2017 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.
NASA Technical Reports Server (NTRS)
Harm, Deborah L.; Taylor, L. C.; Bloomberg, J. J.
2007-01-01
Virtual environments (VE) offer unique training opportunities, particularly for training astronauts and preadapting them to the novel sensory conditions of microgravity. Sensorimotor aftereffects of VEs are often quite similar to adaptive sensorimotor responses observed in astronauts during and/or following space flight. The purpose of this research was to compare disturbances in sensorimotor coordination produced by dome virtual environment display and to examine the effects of exposure duration, and repeated exposures to VR systems. The current study examined disturbances in eye-head-hand (EHH) and eye-head coordination. Preliminary results will be presented. Eleven subjects have participated in the study to date. One training session was completed in order to achieve stable performance on the EHH coordination and VE tasks. Three experimental sessions were performed each separated by one day. Subjects performed a navigation and pick and place task in a dome immersive display VE for 30 or 60 min. The subjects were asked to move objects from one set of 15 pedestals to the other set across a virtual square room through a random pathway as quickly and accurately as possible. EHH coordination was measured before, immediately after, and at 1 hr, 2 hr, 4 hr and 6 hr following exposure to VR. EHH coordination was measured as position errors and reaction time in a pointing task that included multiple horizontal and vertical LED targets. Repeated measures ANOVAs were used to analyze the data. In general, we observed significant increases in position errors for both horizontal and vertical targets. The largest decrements were observed immediately following exposure to VR and showed a fairly rapid recovery across test sessions, but not across days. Subjects generally showed faster RTs across days. Individuals recovered from the detrimental effects of exposure to the VE on position errors within 1-2 hours. The fact that subjects did not significantly improve across days suggests that in order to achieve dual adaptation of EHH coordination may require more than three training sessions. These findings provide some direction for developing training schedules for VE users that facilitate adaptation, support the idea that preflight training of astronauts may serve as useful countermeasure for the sensorimotor effects of space flight, and support the idea that VEs may serve as an analog for sensorimotor effects of spaceflight.
Gestural interaction in a virtual environment
NASA Astrophysics Data System (ADS)
Jacoby, Richard H.; Ferneau, Mark; Humphries, Jim
1994-04-01
This paper discusses the use of hand gestures (i.e., changing finger flexion) within a virtual environment (VE). Many systems now employ static hand postures (i.e., static finger flexion), often coupled with hand translations and rotations, as a method of interacting with a VE. However, few systems are currently using dynamically changing finger flexion for interacting with VEs. In our system, the user wears an electronically instrumented glove. We have developed a simple algorithm for recognizing gestures for use in two applications: automotive design and visualization of atmospheric data. In addition to recognizing the gestures, we also calculate the rate at which the gestures are made and the rate and direction of hand movement while making the gestures. We report on our experiences with the algorithm design and implementation, and the use of the gestures in our applications. We also talk about our background work in user calibration of the glove, as well as learned and innate posture recognition (postures recognized with and without training, respectively).
Salchow, Christina; Valtin, Markus; Seel, Thomas; Schauer, Thomas
2016-06-13
Functional Electrical Stimulation via electrode arrays enables the user to form virtual electrodes (VEs) of dynamic shape, size, and position. We developed a feedback-control-assisted manual search strategy which allows the therapist to conveniently and continuously modify VEs to find a good stimulation area. This works for applications in which the desired movement consists of at least two degrees of freedom. The virtual electrode can be moved to arbitrary locations within the array, and each involved element is stimulated with an individual intensity. Meanwhile, the applied global stimulation intensity is controlled automatically to meet a predefined angle for one degree of freedom. This enables the therapist to concentrate on the remaining degree(s) of freedom while changing the VE position. This feedback-control-assisted approach aims to integrate the user's opinion and the patient's sensation. Therefore, our method bridges the gap between manual search and fully automatic identification procedures for array electrodes. Measurements in four healthy volunteers were performed to demonstrate the usefulness of our concept, using a 24-element array to generate wrist and hand extension.
Viewing medium affects arm motor performance in 3D virtual environments.
Subramanian, Sandeep K; Levin, Mindy F
2011-06-30
2D and 3D virtual reality platforms are used for designing individualized training environments for post-stroke rehabilitation. Virtual environments (VEs) are viewed using media like head mounted displays (HMDs) and large screen projection systems (SPS) which can influence the quality of perception of the environment. We estimated if there were differences in arm pointing kinematics when subjects with and without stroke viewed a 3D VE through two different media: HMD and SPS. Two groups of subjects participated (healthy control, n=10, aged 53.6 ± 17.2 yrs; stroke, n=20, 66.2 ± 11.3 yrs). Arm motor impairment and spasticity were assessed in the stroke group which was divided into mild (n=10) and moderate-to-severe (n=10) sub-groups based on Fugl-Meyer Scores. Subjects pointed (8 times each) to 6 randomly presented targets located at two heights in the ipsilateral, middle and contralateral arm workspaces. Movements were repeated in the same VE viewed using HMD (Kaiser XL50) and SPS. Movement kinematics were recorded using an Optotrak system (Certus, 6 markers, 100 Hz). Upper limb motor performance (precision, velocity, trajectory straightness) and movement pattern (elbow, shoulder ranges and trunk displacement) outcomes were analyzed using repeated measures ANOVAs. For all groups, there were no differences in endpoint trajectory straightness, shoulder flexion and shoulder horizontal adduction ranges and sagittal trunk displacement between the two media. All subjects, however, made larger errors in the vertical direction using HMD compared to SPS. Healthy subjects also made larger errors in the sagittal direction, slower movements overall and used less range of elbow extension for the lower central target using HMD compared to SPS. The mild and moderate-to-severe sub-groups made larger RMS errors with HMD. The only advantage of using the HMD was that movements were 22% faster in the moderate-to-severe stroke sub-group compared to the SPS. Despite the similarity in majority of the movement kinematics, differences in movement speed and larger errors were observed for movements using the HMD. Use of the SPS may be a more comfortable and effective option to view VEs for upper limb rehabilitation post-stroke. This has implications for the use of VR applications to enhance upper limb recovery. © 2011 Subramanian and Levin; licensee BioMed Central Ltd.
Viewing medium affects arm motor performance in 3D virtual environments
2011-01-01
Background 2D and 3D virtual reality platforms are used for designing individualized training environments for post-stroke rehabilitation. Virtual environments (VEs) are viewed using media like head mounted displays (HMDs) and large screen projection systems (SPS) which can influence the quality of perception of the environment. We estimated if there were differences in arm pointing kinematics when subjects with and without stroke viewed a 3D VE through two different media: HMD and SPS. Methods Two groups of subjects participated (healthy control, n = 10, aged 53.6 ± 17.2 yrs; stroke, n = 20, 66.2 ± 11.3 yrs). Arm motor impairment and spasticity were assessed in the stroke group which was divided into mild (n = 10) and moderate-to-severe (n = 10) sub-groups based on Fugl-Meyer Scores. Subjects pointed (8 times each) to 6 randomly presented targets located at two heights in the ipsilateral, middle and contralateral arm workspaces. Movements were repeated in the same VE viewed using HMD (Kaiser XL50) and SPS. Movement kinematics were recorded using an Optotrak system (Certus, 6 markers, 100 Hz). Upper limb motor performance (precision, velocity, trajectory straightness) and movement pattern (elbow, shoulder ranges and trunk displacement) outcomes were analyzed using repeated measures ANOVAs. Results For all groups, there were no differences in endpoint trajectory straightness, shoulder flexion and shoulder horizontal adduction ranges and sagittal trunk displacement between the two media. All subjects, however, made larger errors in the vertical direction using HMD compared to SPS. Healthy subjects also made larger errors in the sagittal direction, slower movements overall and used less range of elbow extension for the lower central target using HMD compared to SPS. The mild and moderate-to-severe sub-groups made larger RMS errors with HMD. The only advantage of using the HMD was that movements were 22% faster in the moderate-to-severe stroke sub-group compared to the SPS. Conclusions Despite the similarity in majority of the movement kinematics, differences in movement speed and larger errors were observed for movements using the HMD. Use of the SPS may be a more comfortable and effective option to view VEs for upper limb rehabilitation post-stroke. This has implications for the use of VR applications to enhance upper limb recovery. PMID:21718542
An Analysis of VR Technology Used in Immersive Simulations with a Serious Game Perspective.
Menin, Aline; Torchelsen, Rafael; Nedel, Luciana
2018-03-01
Using virtual environments (VEs) is a safer and cost-effective alternative to executing dangerous tasks, such as training firefighters and industrial operators. Immersive virtual reality (VR) combined with game aspects have the potential to improve the user experience in the VE by increasing realism, engagement, and motivation. This article investigates the impact of VR technology on 46 immersive gamified simulations with serious purposes and classifies it towards a taxonomy. Our findings suggest that immersive VR improves simulation outcomes, such as increasing learning gain and knowledge retention and improving clinical outcomes for rehabilitation. However, it also has limitations such as motion sickness and restricted access to VR hardware. Our contributions are to provide a better understanding of the benefits and limitations of using VR in immersive simulations with serious purposes, to propose a taxonomy that classifies them, and to discuss whether methods and participants profiles influence results.
Baus, Oliver; Bouchard, Stéphane
2014-01-01
This paper reviews the move from virtual reality exposure-based therapy to augmented reality exposure-based therapy (ARET). Unlike virtual reality (VR), which entails a complete virtual environment (VE), augmented reality (AR) limits itself to producing certain virtual elements to then merge them into the view of the physical world. Although, the general public may only have become aware of AR in the last few years, AR type applications have been around since beginning of the twentieth century. Since, then, technological developments have enabled an ever increasing level of seamless integration of virtual and physical elements into one view. Like VR, AR allows the exposure to stimuli which, due to various reasons, may not be suitable for real-life scenarios. As such, AR has proven itself to be a medium through which individuals suffering from specific phobia can be exposed “safely” to the object(s) of their fear, without the costs associated with programing complete VEs. Thus, ARET can offer an efficacious alternative to some less advantageous exposure-based therapies. Above and beyond presenting what has been accomplished in ARET, this paper covers some less well-known aspects of the history of AR, raises some ARET related issues, and proposes potential avenues to be followed. These include the type of measures to be used to qualify the user’s experience in an augmented reality environment, the exclusion of certain AR-type functionalities from the definition of AR, as well as the potential use of ARET to treat non-small animal phobias, such as social phobia. PMID:24624073
Baus, Oliver; Bouchard, Stéphane
2014-01-01
This paper reviews the move from virtual reality exposure-based therapy to augmented reality exposure-based therapy (ARET). Unlike virtual reality (VR), which entails a complete virtual environment (VE), augmented reality (AR) limits itself to producing certain virtual elements to then merge them into the view of the physical world. Although, the general public may only have become aware of AR in the last few years, AR type applications have been around since beginning of the twentieth century. Since, then, technological developments have enabled an ever increasing level of seamless integration of virtual and physical elements into one view. Like VR, AR allows the exposure to stimuli which, due to various reasons, may not be suitable for real-life scenarios. As such, AR has proven itself to be a medium through which individuals suffering from specific phobia can be exposed "safely" to the object(s) of their fear, without the costs associated with programing complete VEs. Thus, ARET can offer an efficacious alternative to some less advantageous exposure-based therapies. Above and beyond presenting what has been accomplished in ARET, this paper covers some less well-known aspects of the history of AR, raises some ARET related issues, and proposes potential avenues to be followed. These include the type of measures to be used to qualify the user's experience in an augmented reality environment, the exclusion of certain AR-type functionalities from the definition of AR, as well as the potential use of ARET to treat non-small animal phobias, such as social phobia.
Is a dark virtual environment scary?
Toet, Alexander; van Welie, Marloes; Houtkamp, Joske
2009-08-01
This study investigated the effects of nighttime lighting conditions and stress on the affective appraisal of a virtual environment (VE). The effective application of VEs in emotionally intense simulations requires precise control over their characteristics that affect the user's emotions and behavior. It is known that humans have an innate fear of darkness, which increases after exposure to stress and extrapolates to ecologically valid (immersive) VEs. This study investigated if the simulated level of illumination determines the affective appraisal of a VE, particularly after stress. Participants explored either a daytime or a nighttime version of a VE, after performing either an acute psychosocial stress task (Trier Social Stress Test, or TSST) or a relaxing control task. The affective qualities of the VE were appraised through the Russel and Pratt semantic questionnaire on the valence and arousal dimensions. Distress was assessed through free salivary cortisol, the state self-report scale from the Spielberger State-Trait Anxiety Inventory (STAI), and heart rate. In addition, memory for scenic details was tested through a yes-no recognition test. Free salivary cortisol levels, heart rates, and scores on the STAI all indicate that participants who were subjected to the stress task indeed showed signs of distress, whereas participants in the control group showed no signs of stress. The results of the semantic questionnaire and the recognition test showed no significant overall effect of time-of-day conditions on the affective appraisal of the VE or on the recognition of its details, even after prior stress. The experiences of users exploring the VE were not affected by the simulated lighting conditions, even after acute prior stress. Thus, lowering the illumination level in a desktop VE is not sufficient to elicit anxiety. Hence, desktop VE representations are different from immersive VE representations in this respect. This finding has implications for desktop VE representations that are deployed for serious gaming and training purposes.
NASA Technical Reports Server (NTRS)
Garrahan, Steven L.; Tolson, Robert H.; Williams, Robert L., II
1995-01-01
Industrial robots are usually attached to a rigid base. Placing the robot on a compliant base introduces dynamic coupling between the two systems. The Vehicle Emulation System (VES) is a six DOF platform that is capable of modeling this interaction. The VES employs a force-torque sensor as the interface between robot and base. A computer simulation of the VES is presented. Each of the hardware and software components is described and Simulink is used as the programming environment. The simulation performance is compared with experimental results to validate accuracy. A second simulation which models the dynamic interaction of a robot and a flexible base acts as a comparison to the simulated motion of the VES. Results are presented that compare the simulated VES motion with the motion of the VES hardware using the same admittance model. The two computer simulations are compared to determine how well the VES is expected to emulate the desired motion. Simulation results are given for robots mounted to the end effector of the Space Shuttle Remote Manipulator System (SRMS). It is shown that for fast motions of the two robots studied, the SRMS experiences disturbances on the order of centimeters. Larger disturbances are possible if different manipulators are used.
Cogné, Mélanie; Violleau, Marie-Hélène; Klinger, Evelyne; Joseph, Pierre-Alain
2018-01-31
Topographical disorientation is frequent among patients after a stroke and can be well explored with virtual environments (VEs). VEs also allow for the addition of stimuli. A previous study did not find any effect of non-contextual auditory stimuli on navigational performance in the virtual action planning-supermarket (VAP-S) simulating a medium-sized 3D supermarket. However, the perceptual or cognitive load of the sounds used was not high. We investigated how non-contextual auditory stimuli with high load affect navigational performance in the VAP-S for patients who have had a stroke and any correlation between this performance and dysexecutive disorders. Four kinds of stimuli were considered: sounds from living beings, sounds from supermarket objects, beeping sounds and names of other products that were not available in the VAP-S. The condition without auditory stimuli was the control. The Groupe de réflexion pour l'évaluation des fonctions exécutives (GREFEX) battery was used to evaluate executive functions of patients. The study included 40 patients who have had a stroke (n=22 right-hemisphere and n=18 left-hemisphere stroke). Patients' navigational performance was decreased under the 4 conditions with non-contextual auditory stimuli (P<0.05), especially for those with dysexecutive disorders. For the 5 conditions, the lower the performance, the more GREFEX tests were failed. Patients felt significantly disadvantaged by the non-contextual sounds sounds from living beings, sounds from supermarket objects and names of other products as compared with beeping sounds (P<0.01). Patients' verbal recall of the collected objects was significantly lower under the condition with names of other products (P<0.001). Left and right brain-damaged patients did not differ in navigational performance in the VAP-S under the 5 auditory conditions. These non-contextual auditory stimuli could be used in neurorehabilitation paradigms to train patients with dysexecutive disorders to inhibit disruptive stimuli. Copyright © 2018 Elsevier Masson SAS. All rights reserved.
Social values for ecosystem services (SolVES): Documentation and user manual, version 2.0
Sherrouse, Benson C.; Semmens, Darius J.
2012-01-01
In response to the need for incorporating quantified and spatially explicit measures of social values into ecosystem services assessments, the Rocky Mountain Geographic Science Center (RMGSC), in collaboration with Colorado State University, developed a geographic information system (GIS) application, Social Values for Ecosystem Services (SolVES). With version 2.0 (SolVES 2.0), RMGSC has improved and extended the functionality of SolVES, which was designed to assess, map, and quantify the perceived social values of ecosystem services. Social values such as aesthetics, biodiversity, and recreation can be evaluated for various stakeholder groups as distinguished by their attitudes and preferences regarding public uses, such as motorized recreation and logging. As with the previous version, SolVES 2.0 derives a quantitative, 10-point, social-values metric, the Value Index, from a combination of spatial and nonspatial responses to public attitude and preference surveys and calculates metrics characterizing the underlying environment, such as average distance to water and dominant landcover. Additionally, SolVES 2.0 integrates Maxent maximum entropy modeling software to generate more complete social value maps and to produce robust statistical models describing the relationship between the social values maps and explanatory environmental variables. The performance of these models can be evaluated for a primary study area, as well as for similar areas where primary survey data are not available but where social value mapping could potentially be completed using value-transfer methodology. SolVES 2.0 also introduces the flexibility for users to define their own social values and public uses, model any number and type of environmental variable, and modify the spatial resolution of analysis. With these enhancements, SolVES 2.0 provides an improved public domain tool for decisionmakers and researchers to evaluate the social values of ecosystem services and to facilitate discussions among diverse stakeholders regarding the tradeoffs among different ecosystem services in a variety of physical and social contexts ranging from forest and rangeland to coastal and marine.
Sherrouse, Benson C.; Riegle, Jodi L.; Semmens, Darius J.
2010-01-01
In response to the need for incorporating quantified and spatially explicit measures of social values into ecosystem services assessments, the Rocky Mountain Geographic Science Center, in collaboration with Colorado State University, has developed a geographic information system application, Social Values for Ecosystem Services (SolVES). SolVES can be used to assess, map, and quantify the perceived social values of ecosystem services. SolVES derives a quantitative social values metric, the Value Index, from a combination of spatial and nonspatial responses to public attitude and preference surveys. SolVES also generates landscape metrics, such as average elevation and distance to water, calculated from spatial data layers describing the underlying physical environment. Using kernel density calculations and zonal statistics, SolVES derives and maps the 10-point Value Index and reports landscape metrics associated with each index value for social value types such as aesthetics, biodiversity, and recreation. This can be repeated for various survey subgroups as distinguished by their attitudes and preferences regarding public uses of the forests such as motorized recreation and logging for fuels reduction. The Value Index provides a basis of comparison within and among survey subgroups to consider the effect of social contexts on the valuation of ecosystem services. SolVES includes regression coefficients linking the predicted value (the Value Index) to landscape metrics. These coefficients are used to generate predicted social value maps using value transfer techniques for areas where primary survey data are not available. SolVES was developed, and will continue to be enhanced through future versions, as a public domain tool to enable decision makers and researchers to map the social values of ecosystem services and to facilitate discussions among diverse stakeholders regarding tradeoffs between different ecosystem services in a variety of physical and social contexts.
Social Values for Ecosystem Services, version 3.0 (SolVES 3.0): documentation and user manual
Sherrouse, Ben C.; Semmens, Darius J.
2015-01-01
The geographic information system (GIS) tool, Social Values for Ecosystem Services (SolVES), was developed to incorporate quantified and spatially explicit measures of social values into ecosystem service assessments. SolVES 3.0 continues to extend the functionality of SolVES, which was designed to assess, map, and quantify the social values of ecosystem services. Social values—the perceived, nonmarket values the public ascribes to ecosystem services, particularly cultural services, such as aesthetics and recreation—can be evaluated for various stakeholder groups. These groups are distinguishable by their attitudes and preferences regarding public uses, such as motorized recreation and logging. As with previous versions, SolVES 3.0 derives a quantitative 10-point, social-values metric—the value index—from a combination of spatial and nonspatial responses to public value and preference surveys. The tool also calculates metrics characterizing the underlying environment, such as average distance to water and dominant landcover. SolVES 3.0 is integrated with Maxent maximum entropy modeling software to generate more complete social-value maps and offer robust statistical models describing the relationship between the value index and explanatory environmental variables. A model’s goodness of fit to a primary study area and its potential performance in transferring social values to similar areas using value-transfer methodology can be evaluated. SolVES 3.0 provides an improved public-domain tool for decision makers and researchers to evaluate the social values of ecosystem services and to facilitate discussions among diverse stakeholders regarding the tradeoffs among ecosystem services in a variety of physical and social contexts ranging from forest and rangeland to coastal and marine.
Marsh, T; Wright, P; Smith, S
2001-04-01
New and emerging media technologies have the potential to induce a variety of experiences in users. In this paper, it is argued that the inducement of experience presupposes that users are absorbed in the illusion created by these media. Looking to another successful visual medium, film, this paper borrows from the techniques used in "shaping experience" to hold spectators' attention in the illusion of film, and identifies what breaks the illusion/experience for spectators. This paper focuses on one medium, virtual reality (VR), and advocates a transparent or "invisible style" of interaction. We argue that transparency keeps users in the "flow" of their activities and consequently enhances experience in users. Breakdown in activities breaks the experience and subsequently provides opportunities to identify and analyze potential causes of usability problems. Adopting activity theory, we devise a model of interaction with VR--through consciousness and activity--and introduce the concept of breakdown in illusion. From this, a model of effective interaction with VR is devised and the occurrence of breakdown in interaction and illusion is identified along a continuum of engagement. Evaluation guidelines for the design of experience are proposed and applied to usability problems detected in an empirical study of a head-mounted display (HMD) VR system. This study shows that the guidelines are effective in the evaluation of VR. Finally, we look at the potential experiences that may be induced in users and propose a way to evaluate user experience in virtual environments (VEs) and other new and emerging media.
Kuppusamy, Saranya; Thavamani, Palanisami; Megharaj, Mallavarapu; Venkateswarlu, Kadiyala; Lee, Yong Bok; Naidu, Ravi
2016-11-05
Diversity, distribution and composition of bacterial community of soils contaminated long-term with both polycyclic aromatic hydrocarbons (PAHs) and heavy metals were explored for the first time following 454 pyrosequencing. Strikingly, the complete picture of the Gram positive (+ve) and Gram negative (-ve) bacterial profile obtained in our study illustrates novel postulates that include: (1) Metal-tolerant and PAH-degrading Gram -ves belonging to the class Alphaproteobacteria persist relatively more in the real contaminated sites compared to Gram +ves, (2) Gram +ves are not always resistant to heavy metal toxicity, (3) Stenotrophomonas followed by Burkholderia and Pseudomonas are the dominant genera of PAH degraders with high metabolic activity in long-term contaminated soils, (4) Actinobacteria is the predominant group among the Gram +ves in soils contaminated with high molecular weight PAHs that co-exist with toxic heavy metals like Pb, Cu and Zn, (5) Microbial communities are nutrient-driven in natural environments and (6) Catabolically potential Gram +/-ves with diverse applicability to remediate the real contaminated sites evolve eventually in the historically-polluted soils. Thus, the most promising indigenous Gram +/-ve strains from the long-term contaminated sites with increased catabolic potential, enzymatic activity and metal tolerance need to be harnessed for mixed contaminant cleanups. Copyright © 2016 Elsevier B.V. All rights reserved.
Incrocci, L; Hop, W C; Slob, A K
1996-12-01
To establish the number of patients with erectile dysfunction (ED) who appear to be sexually potent when exposed to visual erotic (VES) and vibrotactile stimulation (VIB) and to investigate whether or not older patients are less responsive to VES/VIB than young patients. Retrospective analysis of data on 406 consecutive patients screened for ED with VES, VES + VIB, VES + Intracavernous injection (ICI). Partial or full erection was obtained in 34% of patients with VES, 52% with VES + VIB, 82% with VES + ICI. Men < 40 y (n = 86) responded better than men > 40; between 40 and 80 no differences in penile responses were found. 50% of patients who reported no morning/night erections appeared to have good, rigid nocturnal penile tumescence (NPT). The use of VES, VES + VIB, VES + ICI is strongly recommended in the screening of men with ED of all ages; up to 80% will respond with a good erection. Only a positive penile response has diagnostic significance. The positive results reduce the necessity for further invasive investigations.
Le Quintrec, Jean-Laurent; Bussy, Caroline; Golmard, Jean-Louis; Hervé, Christian; Baulon, Alain; Piette, François
2005-03-01
Very elderly subjects (VES; aged 80 years or older) constitute a special population as they frequently present multiple diseases (polypathology). Results from trials on general adult populations therefore cannot be extrapolated to VES. We performed a census of randomized controlled trials (RCT) on VES published between 1990 and 2002, and carried out a descriptive and methodological analysis of these RCT/VES, comparing them with matched RCT on general adult populations (control RCT, RCT/C). We searched for RCT/VES in two international databases (EMBASE and MEDLINE) and then manually. RCT/C were matched to RCT/VES for disease area and year of publication. The methodological quality of each RCT was assessed with Chalmers' scale. We identified 84 RCT/VES, 63 of which were conclusive and 21, inconclusive. Subjects were institutionalized in 48 RCT, and community dwelling in 11 RCT (unspecified in 25 RCT). Efficacy was the main criterion in 75 RCT; tolerance in 9 RCT. Twenty-six RCT were published by geriatrics journals, and 58 by general medical journals. The RCT/VES covered most of the disease areas of geriatrics. The 84 RCT/VES had a mean methodological quality score of 0.578 +/- 0.157. The matched 84 RCT/C had a mean methodological quality score of 0.592 +/- 0.116 (p = .466). The methodological quality score of RCT/VES increased with the number of included subjects (p = .004) and the year of publication (p = .001). The methodological quality of RCT/VES is equivalent to that of RCT in general adult populations. Nevertheless, RCT/VES remain very scarce, and neglect certain diseases. RCT/VES and the inclusion of very elderly subjects in RCT on adults should be strongly encouraged.
NASA Astrophysics Data System (ADS)
Connolly, Adam; Robson, Matthew D.; Schneider, Jürgen; Burton, Rebecca; Plank, Gernot; Bishop, Martin J.
2017-09-01
Novel low-energy defibrillation therapies are thought to be driven by virtual-electrodes (VEs), due to the interaction of applied monophasic electric shocks with fine-scale anatomical structures within the heart. Significant inter-species differences in the cardiac (micro)-anatomy exist, however, particularly with respect to the degree of endocardial trabeculations, which may underlie important differences in response to low-energy defibrillation protocols. Understanding the interaction of monophasic electric fields with the specific human micro-anatomy is therefore imperative in facilitating the translation and optimisation of these promising experimental therapies to the clinic. In this study, we sought to investigate how electric fields from implanted devices interact with the highly trabeculated human endocardial surface to better understand shock success in order to help optimise future clinical protocols. A bi-ventricular human computational model was constructed from high resolution (350 μm) ex-vivo MR data, including anatomically accurate endocardial structures. Monophasic shocks were applied between a basal right ventricular catheter and an exterior ground. Shocks of varying strengths were applied with both anodal [positive right ventricle (RV) electrode] and cathodal (negative RV electrode) polarities at different states of tissue refractoriness and during induced arrhythmias. Anodal shocks induced isolated positive VEs at the distal side of "detached" trabeculations, which rapidly spread into hyperpolarised tissue on the surrounding endocardial surfaces following the shock. Anodal shocks thus depolarised more tissue 10 ms after the shock than cathodal shocks where the propagation of activation from VEs induced on the proximal side of "detached" trabeculations was prevented due to refractory endocardium. Anodal shocks increased arrhythmia complexity more than cathodal shocks during failed anti-arrhythmia shocks. In conclusion, multiple detached trabeculations in the human ventricle interact with anodal stimuli to induce multiple secondary sources from VEs, facilitating more rapid shock-induced ventricular excitation compared to cathodal shocks. Such a mechanism may help explain inter-species differences in response to shocks and help to develop novel defibrillation strategies.
Yu, W; Sanders, B G; Kline, K
1997-01-01
RRR-alpha-tocopheryl succinate (vitamin E succinate, VES) treatment of murine EL4 T lymphoma cells induced the cells to undergo apoptosis. After 48 hours of VES treatment at 20 micrograms/ml, 95% of cells were apoptotic. Evidence for the induction of apoptosis by VES treatments is based on staining of DNA for detection of chromatin condensation/fragmentation, two-color flow-cytometric analyses of DNA content, and end-labeled DNA and electrophoretic analyses for detection of DNA ladder formation. VES-treated EL4 cells were blocked in the G1 cell cycle phase; however, apoptotic cells came from all cell cycle phases. Analyses of mRNA expression of genes involved in apoptosis revealed decreased c-myc and increased bcl-2, c-fos, and c-jun mRNAs within three to six hours after treatment. Western analyses showed increased c-Jun, c-Fos, and Bcl-2 protein levels. Electrophoretic mobility shift assays showed increased AP-1 binding at 6, 12, and 24 hours after treatment and decreased c-Myc binding after 12 and 24 hours of VES treatment. Treatments of EL4 cells with VES+RRR-alpha-to-copherol reduced apoptosis without effecting DNA synthesis arrest. Treatments of EL4 cells with VES+rac-6-hydroxyl-2, 5,7,8-tetramethyl-chroman-2-carboxylic acid, butylated hydroxytoluene, or butylated hydroxyanisole had no effect on apoptosis or DNA synthesis arrest caused by VES treatments. Analyses of bcl-2, c-myc, c-jun, and c-fos mRNA levels in cells receiving VES + RRR-alpha-tocopherol treatments showed no change from cells receiving VES treatments alone, implying that these changes are correlated with VES treatments but are not causal for apoptosis. However, treatments with VES + RRR-alpha-tocopherol decreased AP-1 binding to consensus DNA oligomer, suggesting AP-1 involvement in apoptosis induced by VES treatments.
A methodology toward manufacturing grid-based virtual enterprise operation platform
NASA Astrophysics Data System (ADS)
Tan, Wenan; Xu, Yicheng; Xu, Wei; Xu, Lida; Zhao, Xianhua; Wang, Li; Fu, Liuliu
2010-08-01
Virtual enterprises (VEs) have become one of main types of organisations in the manufacturing sector through which the consortium companies organise their manufacturing activities. To be competitive, a VE relies on the complementary core competences among members through resource sharing and agile manufacturing capacity. Manufacturing grid (M-Grid) is a platform in which the production resources can be shared. In this article, an M-Grid-based VE operation platform (MGVEOP) is presented as it enables the sharing of production resources among geographically distributed enterprises. The performance management system of the MGVEOP is based on the balanced scorecard and has the capacity of self-learning. The study shows that a MGVEOP can make a semi-automated process possible for a VE, and the proposed MGVEOP is efficient and agile.
Liu, Yuling; Xu, Yingqi; Wu, Minghui; Fan, Lijiao; He, Chengwei; Wan, Jian-Bo; Li, Peng; Chen, Meiwan; Li, Hui
2016-01-01
Mitoxantrone (MIT) is a chemotherapeutic agent with promising anticancer efficacy. In this study, Pluronic F68-vitamine E succinate (F68-VES) amphiphilic polymer micelles were developed for delivering MIT and enhancing its anticancer activity. MIT-loaded F68–VES (F68–VES/MIT) micelles were prepared via the solvent evaporation method with self-assembly under aqueous conditions. F68–VES/MIT micelles were found to be of optimal particle size with the narrow size distribution. Transmission electron microscopy images of F68–VES/MIT micelles showed homogeneous spherical shapes and smooth surfaces. F68–VES micelles had a low critical micelle concentration value of 3.311 mg/L, as well as high encapsulation efficiency and drug loading. Moreover, F68–VES/MIT micelles were stable in the presence of fetal bovine serum for 24 hours and maintained sustained drug release in vitro. Remarkably, the half maximal inhibitory concentration (IC50) value of F68–VES/MIT micelles was lower than that of free MIT in both MDA-MB-231 and MCF-7 cells (two human breast cancer cell lines). In addition, compared with free MIT, there was an increased trend of apoptosis and cellular uptake of F68–VES/MIT micelles in MDA-MB-231 cells. Taken together, these results indicated that F68–VES polymer micelles were able to effectively deliver MIT and largely improve its potency in cancer therapy. PMID:27471384
van Geel, Nanja; Lommerts, Janny E; Bekkenk, Marcel W; Prinsen, Cecilia A C; Eleftheriadou, Viktoria; Taieb, Alain; Picardo, Mauro; Ezzedine, Khaled; Wolkerstorfer, Albert; Speeckaert, Reinhart
2017-03-01
The Vitiligo Extent Score (VES) has recently been introduced as a physicians' score for the clinical assessment of the extent of vitiligo, but a good patient self-assessment score is lacking. The objective is to develop and validate a simplified version of the VES as a patient-reported outcome measure (PROM). After extensive pilot testing, patients were asked to score their vitiligo extent twice with an interval of 2 weeks using the Self Assessment Vitiligo Extent Score (SA-VES). The scores were compared with the physicians' evaluation (VES). The SA-VES demonstrated very good test-retest reliability (intraclass correlation = 0.948, 95% confidence interval [CI]: 0.911-0.970) that was not affected by age, skin type, or vitiligo distribution pattern. According to patients, this evaluation method was easy to use (22% very easy; 49% easy; 29% normal) and required <5 minutes in the majority of patients (73%, <5 minutes; 24%, 5-10 minutes; 2%, 10-15 minutes). Comparison of the SA-VES and the VES demonstrated excellent correlation (r = 0.986, P <.001). Few patients had a dark skin type. The results demonstrate excellent reliability of the SA-VES and excellent correlation with its investigator-reported counterpart (VES). This patient-oriented evaluation method provides a useful tool for the assessment of vitiligo extent. Copyright © 2016 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.
Li, Zhen; Chen, Qixian; Qi, Yan; Liu, Zhihao; Hao, Tangna; Sun, Xiaoxin; Qiao, Mingxi; Ma, Xiaodong; Xu, Ting; Zhao, Xiuli; Yang, Chunrong; Chen, Dawei
2018-04-11
A multifunctional nanoparticulate system composed of methoxy poly(ethylene glycol)-poly(l-histidine)-d-α-vitamin E succinate (MPEG-PLH-VES) copolymers for encapsulation of doxorubicin (DOX) was elaborated with the aim of circumventing the multidrug resistance (MDR) in breast cancer treatment. The MPEG-PLH-VES nanoparticles (NPs) were subsequently functionalized with biotin motif for targeted drug delivery. The MPEG-PLH-VES copolymer exerts no obvious effect on the P-gp expression level of MCF-7/ADR but exhibited a significant influence on the loss of mitochondrial membrane potential, the reduction of intracellular ATP level, and the inhibition of P-gp ATPase activity of MCF-7/ADR cells. The constructed MPEG-PLH-VES NPs exhibited an acidic pH-induced increase on particle size in aqueous solution. The DOX-encapsulated MPEG-PLH-VES/biotin-PEG-VES (MPEG-PLH-VES/B) NPs were characterized to possess high drug encapsulation efficiency of approximate 90%, an average particle size of approximately 130 nm, and a pH-responsive drug release profile in acidic milieu. Confocal laser scanning microscopy (CLSM) investigations revealed that the DOX-loaded NPs resulted in an effective delivery of DOX into MCF-/ADR cells and a notable carrier-facilitated escape from endolysosomal entrapment. Pertaining to the in vitro cytotoxicity evaluation, the DOX-loaded MPEG-PLH-VES/B NPs resulted in more pronounced cytotoxicity to MCF-/ADR cells compared with DOX-loaded MPEG-PLH-VES NPs and free DOX solution. In vivo imaging study in MCF-7/ADR tumor-engrafted mice exhibited that the MPEG-PLH-VES/B NPs accumulated at the tumor site more effectively than MPEG-PLH-VES NPs due to the biotin-mediated active targeting effect. In accordance with the in vitro results, DOX-loaded MPEG-PLH-VES/B NPs showed the strongest inhibitory effect against the MCF-7/ADR xenografted tumors with negligible systemic toxicity, as evidenced by the histological analysis and change of body weight. The multifunctional MPEG-PLH-VES/B nanoparticulate system has been demonstrated to provide a promising strategy for efficient delivery of DOX into MCF-7/ADR cancerous cells and reversing MDR.
Baumgartner, Thomas; Speck, Dominique; Wettstein, Denise; Masnari, Ornella; Beeli, Gian; Jäncke, Lutz
2008-01-01
Virtual reality (VR) is a powerful tool for simulating aspects of the real world. The success of VR is thought to depend on its ability to evoke a sense of “being there”, that is, the feeling of “Presence”. In view of the rapid progress in the development of increasingly more sophisticated virtual environments (VE), the importance of understanding the neural underpinnings of presence is growing. To date however, the neural correlates of this phenomenon have received very scant attention. An fMRI-based study with 52 adults and 25 children was therefore conducted using a highly immersive VE. The experience of presence in adult subjects was found to be modulated by two major strategies involving two homologous prefrontal brain structures. Whereas the right DLPFC controlled the sense of presence by down-regulating the activation in the egocentric dorsal visual processing stream, the left DLPFC up-regulated widespread areas of the medial prefrontal cortex known to be involved in self-reflective and stimulus-independent thoughts. In contrast, there was no evidence of these two strategies in children. In fact, anatomical analyses showed that these two prefrontal areas have not yet reached full maturity in children. Taken together, this study presents the first findings that show activation of a highly specific neural network orchestrating the experience of presence in adult subjects, and that the absence of activity in this neural network might contribute to the generally increased susceptibility of children for the experience of presence in VEs. PMID:18958209
Šelb, J; Kogovšek, R; Šilar, M; Košnik, M; Korošec, P
2016-04-01
No study has assessed the diagnostic sensitivity of rApi m 1 and rVes v 5 on Immulite testing system. To compare the diagnostic sensitivity of commercially available venom recombinant allergens between the currently available immunoassays [ImmunoCAP (CAP) and Immulite (LITE)] and establish their correlation with the severity of the sting reaction. This study evaluated 95 bee venom and 110 yellow jacket venom-allergic subjects. We measured the levels of sIgE to rApi m 1, rVes v 5 (LITE and CAP), rApi m 2 (LITE), rVes v 1 (CAP) and total IgE (CAP). Forty-nine healthy subjects served as controls. The diagnostic sensitivity of rApi m 1 and rVes v 5 was significantly higher with the LITE than with the CAP system (71% vs. 88% and 82% vs. 93%). The specificity of both assays for both allergens was between 94% and 98%. Twenty-nine patients that tested negative for rApi m 1 or rVes v 5 with CAP were positive with LITE, but none of the patients that tested negative with LITE were positive with CAP. The positive values of rApi m 1 and rVes v 5 were on average 2.7 and 2.3 times higher, with the LITE than with the CAP system. The combination of rApi m 1 and rApi m 2 (LITE) and the combination of rVes v 5 (LITE) and rVes v 1 (CAP) almost matched the sensitivity of native venoms (95% and 97%, respectively), whereas the diagnostic sensitivity of the combination of rVes v 5 and rVes v 1 (CAP) did not reach the sensitivity of rVes v 5 (LITE) alone (90% vs. 93%). IgE levels to venom recombinants and total IgE did not correlate with the severity of sting reaction. The use of rApi m 1 and rVes v 5 with the LITE system significantly enhanced diagnostic utility of venom recombinants and should improve the dissection of bee and yellow jacket venom allergy. © 2015 John Wiley & Sons Ltd.
Wang, Jye; Lin, Wender; Chang, Ling-Hui
2018-01-01
The Vulnerable Elders Survey-13 (VES-13) has been used as a screening tool to identify vulnerable community-dwelling older persons for more in-depth assessment and targeted interventions. Although many studies supported its use in different populations, few have addressed Asian populations. The optimal scaling system for the VES-13 in predicting health outcomes also has not been adequately tested. This study (1) assesses the applicability of the VES-13 to predict the mortality of community-dwelling older persons in Taiwan, (2) identifies the best scaling system for the VES-13 in predicting mortality using generalized additive models (GAMs), and (3) determines whether including covariates, such as socio-demographic factors and common geriatric syndromes, improves model fitting. This retrospective longitudinal cohort study analyzed the data of 2184 community-dwelling persons 65 years old or older from the 2003 wave of the national-wide Taiwan Longitudinal Study on Aging. Cox proportional hazards models and Generalized Additive Models (GAMs) were used. The VES-13 significantly predicted the mortality of Taiwan's community-dwelling elders. A one-point increase in the VES-13 score raised the risk of death by 26% (hazard ratio, 1.26; 95% confidence interval, 1.21-1.32). The hazard ratio of death increased linearly with each additional VES-13 score point, suggesting that using a continuous scale is appropriate. Inclusion of socio-demographic factors and geriatric syndromes improved the model-fitting. The VES-13 is appropriate for an Asian population. VES-13 scores linearly predict the mortality of this population. Adjusting the weighting of the physical activity items may improve the performance of the VES-13. Copyright © 2017 Elsevier B.V. All rights reserved.
Jackson, Andrew P.; Otto, Thomas D.; Darby, Alistair; Ramaprasad, Abhinay; Xia, Dong; Echaide, Ignacio Eduardo; Farber, Marisa; Gahlot, Sunayna; Gamble, John; Gupta, Dinesh; Gupta, Yask; Jackson, Louise; Malandrin, Laurence; Malas, Tareq B.; Moussa, Ehab; Nair, Mridul; Reid, Adam J.; Sanders, Mandy; Sharma, Jyotsna; Tracey, Alan; Quail, Mike A.; Weir, William; Wastling, Jonathan M.; Hall, Neil; Willadsen, Peter; Lingelbach, Klaus; Shiels, Brian; Tait, Andy; Berriman, Matt; Allred, David R.; Pain, Arnab
2014-01-01
Babesia spp. are tick-borne, intraerythrocytic hemoparasites that use antigenic variation to resist host immunity, through sequential modification of the parasite-derived variant erythrocyte surface antigen (VESA) expressed on the infected red blood cell surface. We identified the genomic processes driving antigenic diversity in genes encoding VESA (ves1) through comparative analysis within and between three Babesia species, (B. bigemina, B. divergens and B. bovis). Ves1 structure diverges rapidly after speciation, notably through the evolution of shortened forms (ves2) from 5′ ends of canonical ves1 genes. Phylogenetic analyses show that ves1 genes are transposed between loci routinely, whereas ves2 genes are not. Similarly, analysis of sequence mosaicism shows that recombination drives variation in ves1 sequences, but less so for ves2, indicating the adoption of different mechanisms for variation of the two families. Proteomic analysis of the B. bigemina PR isolate shows that two dominant VESA1 proteins are expressed in the population, whereas numerous VESA2 proteins are co-expressed, consistent with differential transcriptional regulation of each family. Hence, VESA2 proteins are abundant and previously unrecognized elements of Babesia biology, with evolutionary dynamics consistently different to those of VESA1, suggesting that their functions are distinct. PMID:24799432
Jackson, Andrew P; Otto, Thomas D; Darby, Alistair; Ramaprasad, Abhinay; Xia, Dong; Echaide, Ignacio Eduardo; Farber, Marisa; Gahlot, Sunayna; Gamble, John; Gupta, Dinesh; Gupta, Yask; Jackson, Louise; Malandrin, Laurence; Malas, Tareq B; Moussa, Ehab; Nair, Mridul; Reid, Adam J; Sanders, Mandy; Sharma, Jyotsna; Tracey, Alan; Quail, Mike A; Weir, William; Wastling, Jonathan M; Hall, Neil; Willadsen, Peter; Lingelbach, Klaus; Shiels, Brian; Tait, Andy; Berriman, Matt; Allred, David R; Pain, Arnab
2014-06-01
Babesia spp. are tick-borne, intraerythrocytic hemoparasites that use antigenic variation to resist host immunity, through sequential modification of the parasite-derived variant erythrocyte surface antigen (VESA) expressed on the infected red blood cell surface. We identified the genomic processes driving antigenic diversity in genes encoding VESA (ves1) through comparative analysis within and between three Babesia species, (B. bigemina, B. divergens and B. bovis). Ves1 structure diverges rapidly after speciation, notably through the evolution of shortened forms (ves2) from 5' ends of canonical ves1 genes. Phylogenetic analyses show that ves1 genes are transposed between loci routinely, whereas ves2 genes are not. Similarly, analysis of sequence mosaicism shows that recombination drives variation in ves1 sequences, but less so for ves2, indicating the adoption of different mechanisms for variation of the two families. Proteomic analysis of the B. bigemina PR isolate shows that two dominant VESA1 proteins are expressed in the population, whereas numerous VESA2 proteins are co-expressed, consistent with differential transcriptional regulation of each family. Hence, VESA2 proteins are abundant and previously unrecognized elements of Babesia biology, with evolutionary dynamics consistently different to those of VESA1, suggesting that their functions are distinct. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.
Castagneto, B; Di Pietrantonj, C; Stevani, I; Anfossi, A; Arzese, M; Giorcelli, L; Giaretto, L
2013-12-01
The importance of prognostic value of the comprehensive geriatric assessment (CGA) is well known in geriatric oncology, but there is no consensus on the use of alternative abbreviated screening methods for the evaluation of older patient disabilities. The participants in this study underwent vulnerable elderly survey 13 (VES 13) at first entry in Oncology Department and were later assessed by a geriatrician according to CGA. A score >3 for VES 13 identified patients as vulnerable. Aim of this study was to evaluate the specificity, sensibility, positive predictive value (PPV), and negative predictive value (NPV) of VES 13 versus cumulative illness rating scale (CIRS), activities of daily living (ADL), instrumental activities of daily living (IADL), and short portable mental status questionnaire (SPMSQ). Hundred and seventeen patients (mean age 78.8 years) entered the study. The NPV of VES was 74.6% for CIRS, 90.1% for IADL, 93.0% for ADL, and 100% for SPMSQ. As for PPV, the VES 13 showed no accuracy. We can conclude that VES 13 demonstrated sufficient accuracy as a screening test in identifying elderly "fit" patients in order to spare the more time-consuming CGA.
Kluckova, Katarina; Zobalova, Renata; Goodwin, Jacob; Tilly, David; Stursa, Jan; Pecinova, Alena; Philimonenko, Anatoly; Hozak, Pavel; Banerjee, Jaideep; Ledvina, Miroslav; Sen, Chandan K.; Houstek, Josef; Coster, Mark J.
2011-01-01
Abstract Aims A plausible strategy to reduce tumor progress is the inhibition of angiogenesis. Therefore, agents that efficiently suppress angiogenesis can be used for tumor suppression. We tested the antiangiogenic potential of a mitochondrially targeted analog of α-tocopheryl succinate (MitoVES), a compound with high propensity to induce apoptosis. Results MitoVES was found to efficiently kill proliferating endothelial cells (ECs) but not contact-arrested ECs or ECs deficient in mitochondrial DNA, and suppressed angiogenesis in vitro by inducing accumulation of reactive oxygen species and induction of apoptosis in proliferating/angiogenic ECs. Resistance of arrested ECs was ascribed, at least in part, to the lower mitochondrial inner transmembrane potential compared with the proliferating ECs, thus resulting in the lower level of mitochondrial uptake of MitoVES. Shorter-chain homologs of MitoVES were less efficient in angiogenesis inhibition, thus suggesting a molecular mechanism of its activity. Finally, MitoVES was found to suppress HER2-positive breast carcinomas in a transgenic mouse as well as inhibit tumor angiogenesis. The antiangiogenic efficacy of MitoVES was corroborated by its inhibitory activity on wound healing in vivo. Innovation and Conclusion We conclude that MitoVES, a mitochondrially targeted analog of α-tocopheryl succinate, is an efficient antiangiogenic agent of potential clinical relevance, exerting considerably higher activity than its untargeted counterpart. MitoVES may be helpful against cancer but may compromise wound healing. Antioxid. Redox Signal. 15, 2923–2935. PMID:21902599
NASA Astrophysics Data System (ADS)
Lian, He; Zhang, Tianhong; Sun, Jin; Pu, Xiaohui; Tang, Yilin; Zhang, Youxi; He, Zhonggui
2014-04-01
The aim of this study was to evaluate the underlying mechanism of enhanced oral absorption of paclitaxel (PTX)-loaded chitosan-vitamin E succinate- N-acetyl- l-cysteine (CS-VES-NAC) nanomicelles from the cellular level. In aqueous solution, CS-VES-NAC copolymer self-assembled into the polymeric nanomicelles, with the size ranging from 190 to 240 nm and the drug loading content as high as 20.5 %. Cytotoxicity results showed that the PTX-loaded nanomicelles exhibited the similar effect to PTX solution (PTX-Sol) on Caco-2 cells, but no toxicity observed for blank CS-VES-NAC nanomicelles. The cellular uptake of PTX was significantly increased by CS-VES-NAC nanomicelles, compared with that of PTX-Sol, due to the possible escapement of P-glycoprotein (P-gp) efflux pumps by endocytosis pathway. Confocal laser scanning microscope (CLSM) images also confirmed CS-VES-NAC nanomicelles could be effectively internalized by Caco-2 cells. More importantly, P app value of PTX-loaded CS-VES-NAC nanomicelles was 2.3-fold higher than that of PTX-Sol, and the efflux ratio decreased by more than 10.8-fold for the nanomicelles. As a consequence of opening of tight junctions and P-gp inhibition induced by free CS-VES-NAC copolymer, the P app value of PTX was almost increased up to 19.5-fold. All the results indicate that CS-VES-NAC copolymer hold great promises as nanocarrier for antitumor drug oral delivery by improving paracellular and transcellular permeation.
Dong, Lan-Feng; Jameson, Victoria J. A.; Tilly, David; Cerny, Jiri; Mahdavian, Elahe; Marín-Hernández, Alvaro; Hernández-Esquivel, Luz; Rodríguez-Enríquez, Sara; Stursa, Jan; Witting, Paul K.; Stantic, Bela; Rohlena, Jakub; Truksa, Jaroslav; Kluckova, Katarina; Dyason, Jeffrey C.; Ledvina, Miroslav; Salvatore, Brian A.; Moreno-Sánchez, Rafael; Coster, Mark J.; Ralph, Stephen J.; Smith, Robin A. J.; Neuzil, Jiri
2011-01-01
Mitochondrial complex II (CII) has been recently identified as a novel target for anti-cancer drugs. Mitochondrially targeted vitamin E succinate (MitoVES) is modified so that it is preferentially localized to mitochondria, greatly enhancing its pro-apoptotic and anti-cancer activity. Using genetically manipulated cells, MitoVES caused apoptosis and generation of reactive oxygen species (ROS) in CII-proficient malignant cells but not their CII-dysfunctional counterparts. MitoVES inhibited the succinate dehydrogenase (SDH) activity of CII with IC50 of 80 μm, whereas the electron transfer from CII to CIII was inhibited with IC50 of 1.5 μm. The agent had no effect either on the enzymatic activity of CI or on electron transfer from CI to CIII. Over 24 h, MitoVES caused stabilization of the oxygen-dependent destruction domain of HIF1α fused to GFP, indicating promotion of the state of pseudohypoxia. Molecular modeling predicted the succinyl group anchored into the proximal CII ubiquinone (UbQ)-binding site and successively reduced interaction energies for serially shorter phytyl chain homologs of MitoVES correlated with their lower effects on apoptosis induction, ROS generation, and SDH activity. Mutation of the UbQ-binding Ser68 within the proximal site of the CII SDHC subunit (S68A or S68L) suppressed both ROS generation and apoptosis induction by MitoVES. In vivo studies indicated that MitoVES also acts by causing pseudohypoxia in the context of tumor suppression. We propose that mitochondrial targeting of VES with an 11-carbon chain localizes the agent into an ideal position across the interface of the mitochondrial inner membrane and matrix, optimizing its biological effects as an anti-cancer drug. PMID:21059645
NASA Astrophysics Data System (ADS)
Singh, Upendra K.; Tiwari, R. K.; Singh, S. B.
2013-03-01
This paper presents the effects of several parameters on the artificial neural networks (ANN) inversion of vertical electrical sounding (VES) data. Sensitivity of ANN parameters was examined on the performance of adaptive backpropagation (ABP) and Levenberg-Marquardt algorithms (LMA) to test the robustness to noisy synthetic as well as field geophysical data and resolving capability of these methods for predicting the subsurface resistivity layers. We trained, tested and validated ANN using the synthetic VES data as input to the networks and layer parameters of the models as network output. ANN learning parameters are varied and corresponding observations are recorded. The sensitivity analysis of synthetic data and real model demonstrate that ANN algorithms applied in VES data inversion should be considered well not only in terms of accuracy but also in terms of high computational efforts. Also the analysis suggests that ANN model with its various controlling parameters are largely data dependent and hence no unique architecture can be designed for VES data analysis. ANN based methods are also applied to the actual VES field data obtained from the tectonically vital geothermal areas of Jammu and Kashmir, India. Analysis suggests that both the ABP and LMA are suitable methods for 1-D VES modeling. But the LMA method provides greater degree of robustness than the ABP in case of 2-D VES modeling. Comparison of the inversion results with known lithology correlates well and also reveals the additional significant feature of reconsolidated breccia of about 7.0 m thickness beneath the overburden in some cases like at sounding point RDC-5. We may therefore conclude that ANN based methods are significantly faster and efficient for detection of complex layered resistivity structures with a relatively greater degree of precision and resolution.
Dai, Caili; Wang, Kai; Liu, Yifei; Fang, Jichao; Zhao, Mingwei
2014-01-01
An investigation was conducted to study the reutilization of clear fracturing flowback fluids composed of viscoelastic surfactants (VES) with additives in surfactant flooding, making the process more efficient and cost-effective. The clear fracturing flowback fluids were used as surfactant flooding system with the addition of α-olefin sulfonate (AOS) for enhanced oil recovery (EOR). The interfacial activity, emulsification activity and oil recovery capability of the recycling system were studied. The interfacial tension (IFT) between recycling system and oil can be reduced by 2 orders of magnitude to 10(-3) mN/m, which satisfies the basic demand of surfactant flooding. The oil can be emulsified and dispersed more easily due to the synergetic effect of VES and AOS. The oil-wet surface of quartz can be easily converted to water-wet through adsorption of surfactants (VES/AOS) on the surface. Thirteen core plug flooding tests were conducted to investigate the effects of AOS concentrations, slug sizes and slug types of the recycling system on the incremental oil recovery. The investigations prove that reclaiming clear fracturing flowback fluids after fracturing operation and reuse it in surfactant flooding might have less impact on environment and be more economical.
Dai, Caili; Wang, Kai; Liu, Yifei; Fang, Jichao; Zhao, Mingwei
2014-01-01
An investigation was conducted to study the reutilization of clear fracturing flowback fluids composed of viscoelastic surfactants (VES) with additives in surfactant flooding, making the process more efficient and cost-effective. The clear fracturing flowback fluids were used as surfactant flooding system with the addition of α-olefin sulfonate (AOS) for enhanced oil recovery (EOR). The interfacial activity, emulsification activity and oil recovery capability of the recycling system were studied. The interfacial tension (IFT) between recycling system and oil can be reduced by 2 orders of magnitude to 10−3 mN/m, which satisfies the basic demand of surfactant flooding. The oil can be emulsified and dispersed more easily due to the synergetic effect of VES and AOS. The oil-wet surface of quartz can be easily converted to water-wet through adsorption of surfactants (VES/AOS) on the surface. Thirteen core plug flooding tests were conducted to investigate the effects of AOS concentrations, slug sizes and slug types of the recycling system on the incremental oil recovery. The investigations prove that reclaiming clear fracturing flowback fluids after fracturing operation and reuse it in surfactant flooding might have less impact on environment and be more economical. PMID:25409507
Saiano, Mario; Pellegrino, Laura; Casadio, Maura; Summa, Susanna; Garbarino, Eleonora; Rossi, Valentina; Dall'Agata, Daniela; Sanguineti, Vittorio
2015-02-19
Lack of social skills and/or a reduced ability to determine when to use them are common symptoms of Autism Spectrum Disorder (ASD). Here we examine whether an integrated approach based on virtual environments and natural interfaces is effective in teaching safety skills in adults with ASD. We specifically focus on pedestrian skills, namely street crossing with or without traffic lights, and following road signs. Seven adults with ASD explored a virtual environment (VE) representing a city (buildings, sidewalks, streets, squares), which was continuously displayed on a wide screen. A markerless motion capture device recorded the subjects' movements, which were translated into control commands for the VE according to a predefined vocabulary of gestures. The treatment protocol consisted of ten 45-minutes sessions (1 session/week). During a familiarization phase, the participants practiced the vocabulary of gestures. In a subsequent training phase, participants had to follow road signs (to either a police station or a pharmacy) and to cross streets with and without traffic lights. We assessed the performance in both street crossing (number and type of errors) and navigation (walking speed, path length and ability to turn without stopping). To assess their understanding of the practiced skill, before and after treatment subjects had to answer a test questionnaire. To assess transfer of the learned skill to real-life situations, another specific questionnaire was separately administered to both parents/legal guardians and the subjects' personal caregivers. One subject did not complete the familiarization phase because of problems with depth perception. The six subjects who completed the protocol easily learned the simple body gestures required to interact with the VE. Over sessions they significantly improved their navigation performance, but did not significantly reduce the errors made in street crossing. In the test questionnaire they exhibited no significant reduction in the number of errors. However, both parents and caregivers reported a significant improvement in the subjects' street crossing performance. Their answers were also highly consistent, thus pointing at a significant transfer to real-life behaviors. Rehabilitation of adults with ASD mainly focuses on educational interventions that have an impact in their quality of life, which includes safety skills. Our results confirm that interaction with VEs may be effective in facilitating the acquisition of these skills.
Geoelectrical characterization by joint inversion of VES/TEM in Paraná basin, Brazil
NASA Astrophysics Data System (ADS)
Bortolozo, C. A.; Couto, M. A.; Almeida, E. R.; Porsani, J. L.; Santos, F. M.
2012-12-01
For many years electrical (DC) and transient electromagnetic (TEM) soundings have been used in a great number of environmental, hydrological and mining exploration studies. The data of both methods are interpreted usually by individual 1D models resulting in many cases in ambiguous models. This can be explained by how the two different methodologies sample the subsurface. The vertical electrical sounding (VES) is good on marking very resistive structures, while the transient electromagnetic sounding (TEM) is very sensitive to map conductive structures. Another characteristic is that VES is more sensitive to shallow structures, while TEM soundings can reach deeper structures. A Matlab program for joint inversion of VES and TEM soundings, by using CRS algorithm was developed aiming explore the best of the both methods. Initially, the algorithm was tested with synthetic data and after it was used to invert experimental data from Paraná sedimentary basin. We present the results of a re-interpretation of 46 VES/TEM soundings data set acquired in Bebedouro region in São Paulo State - Brazil. The previous interpretation was based in geoelectrical models obtained by single inversion of the VES and TEM soundings. In this work we present the results with single inversion of VES and TEM sounding inverted by the Curupira Program and a new interpretation based in the joint inversion of both methodologies. The goal is increase the accuracy in determining the underground structures. As a result a new geoelectrical model of the region is obtained.
Sherrouse, Benson C.; Semmens, Darius J.; Clement, Jessica M.
2014-01-01
Despite widespread recognition that social-value information is needed to inform stakeholders and decision makers regarding trade-offs in environmental management, it too often remains absent from ecosystem service assessments. Although quantitative indicators of social values need to be explicitly accounted for in the decision-making process, they need not be monetary. Ongoing efforts to map such values demonstrate how they can also be made spatially explicit and relatable to underlying ecological information. We originally developed Social Values for Ecosystem Services (SolVES) as a tool to assess, map, and quantify nonmarket values perceived by various groups of ecosystem stakeholders. With SolVES 2.0 we have extended the functionality by integrating SolVES with Maxent maximum entropy modeling software to generate more complete social-value maps from available value and preference survey data and to produce more robust models describing the relationship between social values and ecosystems. The current study has two objectives: (1) evaluate how effectively the value index, a quantitative, nonmonetary social-value indicator calculated by SolVES, reproduces results from more common statistical methods of social-survey data analysis and (2) examine how the spatial results produced by SolVES provide additional information that could be used by managers and stakeholders to better understand more complex relationships among stakeholder values, attitudes, and preferences. To achieve these objectives, we applied SolVES to value and preference survey data collected for three national forests, the Pike and San Isabel in Colorado and the Bridger–Teton and the Shoshone in Wyoming. Value index results were generally consistent with results found through more common statistical analyses of the survey data such as frequency, discriminant function, and correlation analyses. In addition, spatial analysis of the social-value maps produced by SolVES provided information that was useful for explaining relationships between stakeholder values and forest uses. Our results suggest that SolVES can effectively reproduce information derived from traditional statistical analyses while adding spatially explicit, social-value information that can contribute to integrated resource assessment, planning, and management of forests and other ecosystems.
Performance Evaluation of Passive Haptic Feedback for Tactile HMI Design in CAVEs.
Lassagne, Antoine; Kemeny, Andras; Posselt, Javier; Merienne, Frederic
2018-01-01
This article presents a comparison of different haptic systems, which are designed to simulate flat Human Machine Interfaces (HMIs) like touchscreens in virtual environments (VEs) such as CAVEs, and their respective performance. We compare a tangible passive transparent slate to a classic tablet and a sensory substitution system. These systems were tested during a controlled experiment. The performance and impressions from 20 subjects were collected to understand more about the modalities in the given context. The results show that the preferences of the subjects are strongly related to the use-cases and needs. In terms of performance, passive haptics proved to be significantly useful, acting as a space reference and a real-time continuous calibration system, allowing subjects to have lower execution durations and relative errors. Sensory substitution induced perception drifts during the experiment, causing significant performance disparities, demonstrating the low robustness of perception when spatial cues are insufficiently available. Our findings offer a better understanding on the nature of perception drifts and the need of strong multisensory spatial markers for such use-cases in CAVEs. The importance of a relevant haptic modality specifically designed to match a precise use-case is also emphasized.
Chang, Wen-Chang; Shen, Szu-Chuan; Wu, James Swi-Bea
2013-07-24
The unbalance of glucose metabolism in humans may cause the excessive formation of methylglyoxal (MG), which can react with various biomolecules to form the precursor of advanced glycation end products (AGEs). Vescalagin (VES) is an ellagitannin that alleviates insulin resistance in cell study. Results showed that VES reduced the value of oral glucose tolerance test, cardiovascular risk index, AGEs, and tumor necrosis factor-α contents while increasing C-peptide and d-lactate contents significantly in rats orally administered MG and VES together. The preventive effect of VES on MG-induced inflammation and carbohydrate metabolic disorder in rats was thus proved. On the basis of the experiment data, a mechanism, which involves the increase in d-lactate to retard AGE formation and the decrease in cytokine release to prevent β-cell damage, is proposed to explain the bioactivities of VES in antiglycation and in the alleviation of MG-induced carbohydrate metabolic disorder in rats.
Xu, He-Lin; Fan, Zi-Liang; ZhuGe, De-Li; Shen, Bi-Xin; Jin, Bing-Hui; Xiao, Jian; Lu, Cui-Tao; Zhao, Ying-Zheng
2017-10-01
Severe toxicity and poor tumour penetration are two intrinsic limited factors to hinder the broad clinical application for most of first-line chemotherapeutics. In this study, a novel vitamin E succinate-grafted ε-polylysine (VES-g-PLL) polymer was synthesized by using ε-polylysine as backbone. By adjusting VES graft ratio, VES-g-PLL (50) with a theoretic VES graft ratio of 50% could self-assemble into a supermolecular micelle with a hydrodynamic diameter (D h ) of ca.20nm, and Zeta potential of 19.6mV. VES-g-PLL micelles themselves displayed a strong anti-tumour effect on glioma. The poorly water-soluble curcumin was effectively encapsulated in VES-g-PLL micelles with the drug loading amount and entrapment efficiency reaching 4.32% and 82.27%, respectively. In a physiologic medium, curcumin-loaded VES-g-PLL micelles (Cur-Micelles) not only remained stable without obvious drug leakage but also sustained the release of its encapsulated curcumin for a long time. Because of the ultra-small size and positively-charged surface, Cur-Micelles penetrated the deeper tumour zone than free curcumin, resulting in a significant inhibition of tumour spheroids growth. Moreover, in vivo strong antitumor effect of Cur-Micelles was also exhibited at assistance of ultrasound-targeted microbubble destruction and the real-time MRI imaging demonstrated a nearly complete suppression of glioma after 28days of treatment. TUNEL staining showed that the therapeutic mechanism of Cur-Micelles was relevant to the apoptosis of tumour cells. Finally, in vivo nontoxicity of Cur-Micelles against normal organs including heart, liver, spleen, lung and kidney tissues was also demonstrated by the HE staining. In conclusion, VES-g-PLL micelles may serve as a potential carrier for curcumin to enhance tumour penetration and improve therapeutic effect on glioma. Copyright © 2017 Elsevier B.V. All rights reserved.
Contact dermatitis in children.
Rademaker, M; Forsyth, A
1989-02-01
125 children under the age of 12 years were patch tested over a period of 7 years. 60 (48%) of the children had 1 or more positive (+ve) reactions, of which 92% (55/60) were considered relevant. The most common allergens were metals (35 + ves), fragrances (24 + ves) and rubber compounds (11 + ves). 40 of the children were also tested for contact urticaria against food additives and fragrances, of whom 20 were positive (benzoic acid 14, cinnamaldehyde 12).
High Energy Lithium-Ion VES Cells And Batteries Performances
NASA Astrophysics Data System (ADS)
Castric, A.-F.; Lawson, S.; Borthomieu, Y.
2011-10-01
b Saft's Space VES range of lithium-ion cells have been designed specifically to meet the satellites on-board power need, while meeting the legitimate high levels of requirements for space products. The purpose of the paper is to develop how the VES batteries designs have progressively evolved in order to accommodate the needs, requirements and constraints evolutions. The following topics will be presented: - Description of the main design features of the VES Li- ion batteries. - How the optimised battery configuration is selected against the required EOL power need or other constraints. - Presentation of the batteries performances (electrical, mechanical, thermal, interface, weight, ...). - Measures implemented in order to maintain these performances, and to guarantee the best product quality as per space standards.
Biganzoli, Laura; Mislang, Anna Rachelle; Di Donato, Samantha; Becheri, Dimitri; Biagioni, Chiara; Vitale, Stefania; Sanna, Giuseppina; Zafarana, Elena; Gabellini, Stefano; Del Monte, Francesca; Mori, Elena; Pozzessere, Daniele; Brunello, Antonella; Luciani, Andrea; Laera, Letizia; Boni, Luca; Di Leo, Angelo; Mottino, Giuseppe
2017-07-01
Frailty increases the risk of adverse health outcomes and/or dying when exposed to a stressor, and routine frailty assessment is recommended to guide treatment decision. The Balducci frailty criteria (BFC) and Fried frailty criteria (FFC) are commonly used, but these are time consuming. Vulnerable Elders Survey-13 (VES-13) score of ≥7, a simple and resource conserving function-based scoring system, may be used instead. This prospective study evaluates the performance of VES-13 in parallel with BFC and FFC, to identify frailty in elderly patients with early-stage cancer. Patients aged ≥70 years with early-stage solid tumors were classified as frail/nonfrail based on BFC (≥1 criteria), FFC (≥3 criteria), and VES-13 (score ≥ 7). All patients were assessed for functional decline and death. We evaluated 185 patients. FFC had a 17% frailty rate, whereas BFC and VES-13 both had 25%, with poor concordance seen between the three geriatric tools. FFC (hazard ratio = 1.99, p = .003) and VES-13 (hazard ratio = 2.81, p < .001) strongly discriminated for functional decline, whereas BFC (hazard ratio = 3.29, p < .001) had the highest discriminatory rate for deaths. BFC and VES-13 remained prognostic for overall survival in multivariate analysis correcting for age, tumor type, stage, and systemic treatment. A VES-13 score of ≥7 is a valuable discriminating tool for predicting functional decline or death and can be used as a frailty-screening tool among older cancer patients in centers with limited resources to conduct a comprehensive geriatric assessment. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Müller, U; Schmid-Grendelmeier, P; Hausmann, O; Helbling, A
2012-08-01
Diagnostic tests in patients with Hymenoptera venom allergy are frequently positive to venoms of both honey bee and wasp (Vespula). Component-resolved analysis with recombinant species-specific major allergens (rSSMA) may help to distinguish true double sensitization from crossreactivity. Included were 121 patients with systemic allergic reactions to Hymenoptera stings, 76 with double positivity of serum-specific IgE (sIgE) to both venoms, 45 with single positivity to bee or wasp venom, and 32 controls without history of systemic reactions to Hymenoptera stings and no sIgE to whole venoms. In venom-allergic patients and controls, sIgE to rSSMA Api m 1 of bee venom and to Ves v 1 and Ves v 5 of wasp venom were tested by ImmunoCAP. Only 47% of 76 patients with double positivity to whole venoms reacted also to rSSMA of both species. Specificity of sIgE to the 3 rSSMA was very high, with no sIgE to rSSMA of the other species in single-positive venom-allergic patients and only one control with low sIgE to Ves v 1. All wasp-allergic single-positive patients had sIgE to Ves v 5 and/or Ves v 1, and 78.3% of single-positive bee venom-allergic patients had sIgE to Api m 1. Specificity of sIgE to rSSMA of both species is excellent. Sensitivity of sIgE to rSSMA was optimal for wasp venom. Sensitivity of bee venom Api m 1 could be increased by adding rSSMA of other important bee venom allergens. © 2012 John Wiley & Sons A/S.
Assessment of Diesse Ves-matic automated system for measuring erythrocyte sedimentation rate.
Caswell, M; Stuart, J
1991-01-01
Measurement of the erythrocyte sedimentation rate (ESR) using a closed tube system reduces the biohazard risk to laboratory staff. The Diesse Ves-matic system offers manual or vacuum collection of blood into plastic tubes, automated mixing of the sample, and automated reading of the end point after 20 minutes of sedimentation. This system was compared with the 1977 Westergren ESR method of the International Council for Standardization in Haematology (ICSH) and with the 1988 ICSH undiluted ESR method. Manually collected Ves-matic samples showed good agreement with ICSH values, although there was a tendency to false low results at low ESR values which may represent dilution of plasma protein with excess citrate. Vacuum collected Ves-matic samples also showed good agreement with ICSH values, although there was a tendency to false high results which may reflect a change in the blood: citrate ratio caused by loss of anticoagulant diluent or vacuum from plastic tubes during storage. The Diesse Ves-matic system incorporates several improvements over previous technology and offers a safer, quicker, and more standardised ESR. PMID:1752986
Joshi, Amit; Tandon, Nidhi; Patil, Vijay M; Noronha, Vanita; Gupta, Sudeep; Bhattacharjee, Atanu; Prabhash, Kumar
2017-01-01
Comprehensive geriatric assessment (CGA) in routine practice is not logistically feasible. Short geriatric screening tools are available for selecting patients for CGA. However none of them is validated in India. In this analysis we aim to compare the level of agreement between three commonly used short screening tools (Flemish version of TRST (fTRST), G8 and VES-13. Patients ≥65 years with a solid tumor malignancy undergoing cancer directed treatment were interviewed between March 2013 to July 2014. Geriatric screening with G8, fTRST and VES-13 tools was performed in these patients. G8 score ≤14, fTRST score ≥1 and VES-13 score ≥3 were taken as indicators for the presence of a high risk geriatric profile respectively. R version 3.1.2 was used for analysis. Cohen kappa agreement statistics was used to compare the agreement between the 3 tools. p value of 0.05 was taken as significant. The kappa statistics value for agreement between G8 score and fTRST, between VES-13 and fTRST and between VES-13 and G8 were 0.12 (P = 0.04), 0.16 (P = 0.07) and 0.05 (P = 0.45) respectively. It was found that maximum agreement was observed for VES-13 and fTRST. The agreement value of VES-13 and fTRST observed was 59.44 %(39.63% for high risk profile and 19.81% for low risk profile). The agreement value of G-8 and fTRST was 39.62% (2.83% only for high risk profile and 36.79% for low risk profile). The lowest agreement was between G8 and VES-13, 35.84% (7.54% for high risk detection and 28.30% for low risk detection). There was poor agreement (in view of kappa value been below 0.2) between the 3 short geriatric screening tools. Research needs to be directed to compare the agreement level between these 3 scales and CGA, so that the appropriate short screening tool can be selected for routine use.
NASA Astrophysics Data System (ADS)
Lichnovský, J.; Kupka, J.; Štěrbová, V.; Andráš, P.; Midula, P.
2017-10-01
The deposits, located in Nová Ves and Zlaté Hory were well known and important sources of metal ore in Jesenniky region in the past. Especially the one in Nová Ves, which is recently the most important hydrothermal deposit of venous type in the whole area. The mining activity, aimed on lead and zinc minerals was practically permanent here from the middle-age to 1959. On the other hand, the site in Zlaté Hory is the most important ore deposit in Czech Silesia. The non-venous types of polymetallic, copper and gold deposits, evolved in the complex of metamorphic devon rocks are located on south and south-west directions of the area. Long and permanent mining industry caused remarkable changes in the local environment, creating mine heaps and depressions. The probability, that dump material contains potentially toxic substances that could be possibly leaked into surrounded environment is high. This contribution presents the part of complex study results, aimed on evaluating of potential environmental impacts in above mentioned locations. It aims on contamination, caused by potentially toxic heavy metals (Pb, Zn, Cu, Ni, Fe, Mn, Co, Cd, Cr and As) at the sites, exposed to mining activity in the past. The study focus on the contamination of these sites and evaluate them as potential risk for surrounded environment.
VES/TEM 1D joint inversion by using Controlled Random Search (CRS) algorithm
NASA Astrophysics Data System (ADS)
Bortolozo, Cassiano Antonio; Porsani, Jorge Luís; Santos, Fernando Acácio Monteiro dos; Almeida, Emerson Rodrigo
2015-01-01
Electrical (DC) and Transient Electromagnetic (TEM) soundings are used in a great number of environmental, hydrological, and mining exploration studies. Usually, data interpretation is accomplished by individual 1D models resulting often in ambiguous models. This fact can be explained by the way as the two different methodologies sample the medium beneath surface. Vertical Electrical Sounding (VES) is good in marking resistive structures, while Transient Electromagnetic sounding (TEM) is very sensitive to conductive structures. Another difference is VES is better to detect shallow structures, while TEM soundings can reach deeper layers. A Matlab program for 1D joint inversion of VES and TEM soundings was developed aiming at exploring the best of both methods. The program uses CRS - Controlled Random Search - algorithm for both single and 1D joint inversions. Usually inversion programs use Marquadt type algorithms but for electrical and electromagnetic methods, these algorithms may find a local minimum or not converge. Initially, the algorithm was tested with synthetic data, and then it was used to invert experimental data from two places in Paraná sedimentary basin (Bebedouro and Pirassununga cities), both located in São Paulo State, Brazil. Geoelectric model obtained from VES and TEM data 1D joint inversion is similar to the real geological condition, and ambiguities were minimized. Results with synthetic and real data show that 1D VES/TEM joint inversion better recovers simulated models and shows a great potential in geological studies, especially in hydrogeological studies.
Assessing a VR-based learning environment for anatomy education.
Hoffman, H; Murray, M; Hettinger, L; Viirre, E
1998-01-01
The purpose of the research proposed herein is to develop an empirical, methodological tool for the assessment of visual depth perception in virtual environments (VEs). Our goal is to develop and employ a behaviorally-based method for assessing the impact of VE design features on the perception of visual depth as indexed by the performance of fundamental perceptual-motor activities. Specifically, in this experiment we will assess the affect of two dimensions of VE system design--(1) viewing condition or "level of immersion", and (2) layout/design of the VE--on the performance of an engaging, game-like task. The characteristics of the task to be employed are as follows--(1) it places no demands on cognition in the form of problem solving, retrieval of previously learned information, or other analytic activity in order to assure that (2) variations in task performance can be exclusively attributed to the extent to which the experimental factors influence visual depth perception. Subjects' performance will be assessed in terms of the speed and accuracy of task performance, as well as underlying dimensions of performance such as workload, fatigue, and physiological well being (i.e., cybersickness). The results of this experiment will provide important information on the effect of VE immersion and other VE design issues on human perception and performance. Further development, refinement, and validation of this behaviorally-based methodology will be pursued to provide user-centered design criteria for the design and use of VE systems.
Increased level of antibodies cross-reacting with Ves v 5 and CRISP-2 in MAR-positive patients.
Brunner-Agten, S; Pavlovic, R; Müller, L; Horn, M P; Huber, A R; Stadler, B M; Vogel, M
2013-01-01
Anti-sperm antibodies (ASA) have been described to be involved in immunological infertility. A possible antigen for ASA is the human cysteine-rich secretory protein 2 (CRISP-2), a sperm surface protein important in sperm-oocyte interaction. Furthermore, anti-CRISP-2 antibodies were shown to decrease fertility rates in vitro. Recently, we have reported cross-reacting antibodies recognizing CRISP-2 and antigen 5 from yellow jacket venom (Ves v 5) in human serum. Here, we investigated anti-Ves v 5 and CRISP-2 antibodies in sera from two groups of donors: MAR+ and MAR- patients. A higher incidence of allergy against hymenoptera venom was found in MAR+ patients. Interestingly, affinity-purified ASA from MAR+ patients' sera reacted against both Ves v 5 and CRISP-2, leading to sperm immobilization. Immunofluorescence analysis showed that ASA bound to the sperm surface, including the head part where CRISP-2 is localized. Taken together, these results showed a higher incidence of antibodies cross-reacting with Ves v 5 and CRISP-2 in MAR+ patients. This leads to the hypothesis that MAR+ patients may have a higher risk to develop wasp allergy. Copyright © 2012 S. Karger AG, Basel.
Owusu, Cynthia; Margevicius, Seunghee; Schluchter, Mark; Koroukian, Siran M; Schmitz, Kathryn H; Berger, Nathan A
2016-08-15
The purpose of this study was to determine the ability of the Vulnerable Elders Survey (VES-13) to predict the composite outcome of functional decline and death within 12 months of breast cancer treatment among women 65 years old or older with newly diagnosed stage I to III breast cancer. Two hundred and six participants were recruited from ambulatory oncology clinics at an academic center between April 2008 and April 2013. Participants competed the VES-13 at baseline just before neoadjuvant/adjuvant treatment. The primary outcome, functional decline/death, was defined as either a decrease of at least 1 point on the Activities of Daily Living scale and/or the Instrumental Activities of Daily Living scale or death between baseline and 12 months (yes or no). One hundred and eighty four participants (89%) completed 12 months of follow-up. Twenty-two percent functionally declined (n = 34) or died (n = 7). Univariately, with increasing VES-13 scores, the estimated risk of functional decline/death rose from 23% for participants with a VES-13 score of 3 to 76% for participants with a VES-13 score of 10. In multivariate logistic regression analysis, VES-13 scores (adjusted odds ratio, 1.37; 95% confidence interval, 1.18-1.57) and having a high school education or less (adjusted odds ratio, 2.47; 95% confidence interval, 1.08-5.65) were independent predictors of functional decline/death (area under the receiver operator curve, 0.79). Among older women with newly diagnosed nonmetastatic breast cancer, approximately 1 in 5 functionally declined and/or died within 12 months of breast cancer treatment initiation. Women with high school education or less were disproportionately affected. The VES-13 is a useful instrument for the early identification of those at risk for functional decline and/or death. Cancer 2016;122:2579-86. © 2016 American Cancer Society. © 2016 American Cancer Society.
Classification of O Stars in the Yellow-Green: The Exciting Star VES 735
NASA Astrophysics Data System (ADS)
Kerton, C. R.; Ballantyne, D. R.; Martin, P. G.
1999-05-01
Acquiring data for spectral classification of heavily reddened stars using traditional criteria in the blue-violet region of the spectrum can be prohibitively time consuming using small to medium sized telescopes. One such star is the Vatican Observatory emission-line star VES 735, which we have found excites the H II region KR 140. In order to classify VES 735, we have constructed an atlas of stellar spectra of O stars in the yellow-green (4800-5420 Å). We calibrate spectral type versus the line ratio He I lambda4922:He II lambda5411, showing that this ratio should be useful for the classification of heavily reddened O stars associated with H II regions. Application to VES 735 shows that the spectral type is O8.5. The absolute magnitude suggests luminosity class V. Comparison of the rate of emission of ionizing photons and the bolometric luminosity of VES 735, inferred from radio and infrared measurements of the KR 140 region, to recent stellar models gives consistent evidence for a main-sequence star of mass 25 M_solar and age less than a few million years with a covering factor 0.4-0.5 by the nebular material. Spectra taken in the red (6500-6700 Å) show that the stellar Hα emission is double-peaked about the systemic velocity and slightly variable. Hβ is in absorption, so that the emission-line classification is ``(e)''. However, unlike the case of the more well-known O(e) star zeta Oph, the emission from VES 735 appears to be long-lived rather than episodic.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-09-23
... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration Proposed Information Collection; Comment Request; Social Values of Ecosystem Services (SolVES) in Marine Protected Areas for Management Decision-Making AGENCY: National Oceanic and Atmospheric Administration, Commerce. ACTION: Notice...
Sherrouse, B.C.; Semmens, D.J.
2010-01-01
Ecosystem services can be defined in various ways; simply put, they are the benefits provided by nature, which contribute to human well-being. These benefits can range from tangible products such as food and fresh water to cultural services such as recreation and esthetics. As the use of these benefits continues to increase, additional pressures are placed on the natural ecosystems providing them. This makes it all the more important when assessing possible tradeoffs among ecosystem services to consider the human attitudes and preferences that express underlying social values associated with their benefits. While some of these values can be accounted for through economic markets, other values can be more difficult to quantify, and attaching dollar amounts to them may not be very useful in all cases. Regardless of the processes or units used for quantifying such values, the ability to map them across the landscape and relate them to the ecosystem services to which they are attributed is necessary for effective assessments. To address some of the needs associated with quantifying and mapping social values for inclusion in ecosystem services assessments, scientists at the Rocky Mountain Geographic Science Center (RMGSC), in collaboration with Colorado State University, have developed a public domain tool, Social Values for Ecosystem Services (SolVES). SolVES is a geographic information system (GIS) application designed to use data from public attitude and preference surveys to assess, map, and quantify social values for ecosystem services. SolVES calculates and maps a 10-point Value Index representing the relative perceived social values of ecosystem services such as recreation and biodiversity for various groups of ecosystem stakeholders. SolVES output can also be used to identify and model relationships between social values and physical characteristics of the underlying landscape. These relationships can then be used to generate predicted Value Index maps for areas where survey data are not available. RMGSC will continue to develop more robust versions of SolVES by pursuing opportunities to work with land and resource managers as well as other researchers to apply SolVES to specific ecosystem management problems.
Geomorphological and Geoelectric Techniques for Kwoi's Multiple Tremor Assessment
NASA Astrophysics Data System (ADS)
Dikedi, P. N.
2017-12-01
This work epicentres on geomorphological and geoelectric techniques for multiple tremor assessment in Kwoi, Nigeria. Earth tremor occurrences have been noted by Akpan and Yakubu (2010) within the last 70 years, in nine regions in Nigeria; on September 11,12,20,22, 23 and 24, 2016, additional earth tremors rocked the village of Kwoi eleven times. Houses cracked and collapsed, a rock split and slid and smoke evolved at N9027''5.909''', E800'44.951'', from an altitude of 798m. By employing the Ohmega Meter and Schlumberger configuration, four VES points are sounded for subsurface structure characterisation. Thereafter, a cylindrical steel ring is hammered into the ground at the first point (VES 1) and earth samples are scooped from this location; this procedure is repeated for other points (VES 2, 3 and 4). Winresist, Geo-earth, and Surfer version 12.0.626 software are employed to generate geo-sections, lithology, resistivity profile, Iso resistivity and Isopach maps, of the region. Outcome of results reveal some lithological formations of lateritic topsoil, fractured basement and fresh basement; additionally, results reveal 206.6m, 90.7m, 73.2m and 99.4m fractured basement thicknesses for four points. Scooped samples are transferred to the specimen stage of a Scanning Electron Microscope (SEM). SEM images show rounded inter-granular boundaries—the granular structures act like micro-wheels making the upper crustal mass susceptible to movement at the slightest vibration. Collapsed buildings are sited around VES1 location; samples from VES 1 are the most well fragmented sample owing to multiple microfractures—this result explains why VES 1 has the thickest fractured basement. Abrupt frictional sliding occurs between networks of fault lines; there is a likelihood that friction is most intense at the rock slide site on N9027'21.516'' and E800'44.9993'', VES 1 at N9027'5.819'' and E8005'3.1120'' and smoke sites—holo-centres are suspected below these locations. The presence of borehole facilities and quarry activities around the region serve as artificial causal factors of these tremors.
NASA Astrophysics Data System (ADS)
Zhong, L.; Wu, X.; Dai, C.
2017-12-01
Over the past decade, the rapid rise of unconventional shale gas and tight sandstone oil development through horizontal drilling and high volume hydraulic fracturing has expanded the extraction of hydrocarbon resources. Hydraulic fracturing fluids play very important roles in enhanced oil/gas recovery. However, damage to the reservoir rock and environmental contamination caused by hydraulic fracturing flowback fluids has raised serious concerns. The development of reservoir rock friendly and environmental benign fracturing fluids is in immediate demand. Studies to improve properties of hydraulic fracturing fluids have found that viscoelastic surfactant (VES) fracturing fluid can increase the productivity of gas/oil and be efficiently extracted after fracturing. Compared to conventional polymer fracturing fluid, VES fracturing fluid has many advantages, such as few components, easy preparation, good proppant transport capacity, low damage to cracks and formations, and environment friendly. In this work, we are developing a novel CO2-responsive VES fracking fluid that can readily be reused. This fluid has a gelling-breaking process that can be easily controlled by the presence of CO2 and its pressure. We synthesized erucamidopropyl dimethylamine (EA) as a thickening agent for hydraulic fracturing fluid. The influence of temperature, presence of CO2 and pressure on the viscoelastic behavior of this fluid was then investigated through rheological measurements. The fracturing fluid performance and recycle property were lastly studied using core flooding tests. We expect this fluid finds applications not only in enhanced oil/gas recovery, but also in areas such as controlling groundwater pollution and microfluidics.
Estimating Distance in Real and Virtual Environments: Does Order Make a Difference?
Ziemer, Christine J.; Plumert, Jodie M.; Cremer, James F.; Kearney, Joseph K.
2010-01-01
This investigation examined how the order in which people experience real and virtual environments influences their distance estimates. Participants made two sets of distance estimates in one of the following conditions: 1) real environment first, virtual environment second; 2) virtual environment first, real environment second; 3) real environment first, real environment second; or 4) virtual environment first, virtual environment second. In Experiment 1, participants imagined how long it would take to walk to targets in real and virtual environments. Participants’ first estimates were significantly more accurate in the real than in the virtual environment. When the second environment was the same as the first environment (real-real and virtual-virtual), participants’ second estimates were also more accurate in the real than in the virtual environment. When the second environment differed from the first environment (real-virtual and virtual-real), however, participants’ second estimates did not differ significantly across the two environments. A second experiment in which participants walked blindfolded to targets in the real environment and imagined how long it would take to walk to targets in the virtual environment replicated these results. These subtle, yet persistent order effects suggest that memory can play an important role in distance perception. PMID:19525540
Toxic Anterior Segment Syndrome Outbreak after Cataract Surgery Triggered by Viscoelastic Substance.
Altıntaş, AyşeGül Koçak; Ciritoğlu, Meryem Yaşar; BeyazyıldıZ, Özlem; Can, Çiğdem Ülkü; Polat, Sibel
2017-01-01
The purpose of this study is to present toxic anterior segment syndrome (TASS) outbreak at our clinic and discuss possible causes of TASS. Thirty-four eyes of 34 patients developed TASS in a consecutive 2 weeks period were included in this study. Both anterior segment and fundus examinations were performed before and after uncomplicated cataract surgery. During the follow-up period, clinical features and all possible causes were evaluated including perioperative products and processing such as sterilization technique of surgical instruments, irrigating solutions, drugs, viscoelastic substance (VES), and intraocular lens. Patients had corneal edema, anterior chamber reactions, and decreased vision. No patient had purulent secretion, chemosis, lid involvement, and pain. At first 2 postoperative days, patients treated as infectious endophthalmitis by topical and oral antibiotics and then TASS was suspected, and patients treated completely with topical steroids. Suspected cause for TASS was VES substance, 2% sodium hyaluronate which had newly been used as VES product in phacoemulsification surgery. No new case has occurred after stopped usage of this VES product. As far as we know, this is the largest report of TASS outbreak in the shortest period from the same clinic caused by VES. Suboptimal products of surgical materials can be the cause of TASS. Close monitoring of each surgical step and elimination of causative agent can prevent the outbreaks of TASS.
Plancher, Gaën; Gyselinck, Valérie; Piolino, Pascale
2018-01-01
Memory is one of the most important cognitive functions in a person's life as it is essential for recalling personal memories and performing many everyday tasks. Although a huge number of studies have been conducted in the field, only a few of them investigated memory in realistic situations, due to methodological issues. The various tools that have been developed using virtual environments (VEs) have gained popularity in cognitive psychology and neuropsychology because they enable to create naturalistic and controlled situations, and are thus particularly adapted to the study of episodic memory (EM), for which an ecological evaluation is of prime importance. EM is the conscious recollection of personal events combined with their phenomenological and spatiotemporal encoding contexts. Using an original paradigm in a VE, the objective of the present study was to characterize the construction of episodic memories. While the concept of working memory has become central in the understanding of a wide range of cognitive functions, its role in the integration of episodic memories has seldom been assessed in an ecological context. This experiment aimed at filling this gap by studying how EM is affected by concurrent tasks requiring working memory resources in a realistic situation. Participants navigated in a virtual town and had to memorize as many elements in their spatiotemporal context as they could. During learning, participants had either to perform a concurrent task meant to prevent maintenance through the phonological loop, or a task aimed at preventing maintenance through the visuospatial sketchpad, or no concurrent task. EM was assessed in a recall test performed after learning through various scores measuring the what, where and when of the memories. Results showed that, compared to the control condition with no concurrent task, the prevention of maintenance through the phonological loop had a deleterious impact only on the encoding of central elements. By contrast, the prevention of visuo-spatial maintenance interfered both with the encoding of the temporal context and with the binding. These results suggest that the integration of realistic episodic memories relies on different working memory processes that depend on the nature of the traces.
NASA Astrophysics Data System (ADS)
Bortolozo, Cassiano Antonio; Bokhonok, Oleg; Porsani, Jorge Luís; Monteiro dos Santos, Fernando Acácio; Diogo, Liliana Alcazar; Slob, Evert
2017-11-01
Ambiguities in geophysical inversion results are always present. How these ambiguities appear in most cases open to interpretation. It is interesting to investigate ambiguities with regard to the parameters of the models under study. Residual Function Dispersion Map (RFDM) can be used to differentiate between global ambiguities and local minima in the objective function. We apply RFDM to Vertical Electrical Sounding (VES) and TEM Sounding inversion results. Through topographic analysis of the objective function we evaluate the advantages and limitations of electrical sounding data compared with TEM sounding data, and the benefits of joint inversion in comparison with the individual methods. The RFDM analysis proved to be a very interesting tool for understanding the joint inversion method of VES/TEM. Also the advantage of the applicability of the RFDM analyses in real data is explored in this paper to demonstrate not only how the objective function of real data behaves but the applicability of the RFDM approach in real cases. With the analysis of the results, it is possible to understand how the joint inversion can reduce the ambiguity of the methods.
Using smartphone technology to deliver a virtual pedestrian environment: usability and validation.
Schwebel, David C; Severson, Joan; He, Yefei
2017-09-01
Various programs effectively teach children to cross streets more safely, but all are labor- and cost-intensive. Recent developments in mobile phone technology offer opportunity to deliver virtual reality pedestrian environments to mobile smartphone platforms. Such an environment may offer a cost- and labor-effective strategy to teach children to cross streets safely. This study evaluated usability, feasibility, and validity of a smartphone-based virtual pedestrian environment. A total of 68 adults completed 12 virtual crossings within each of two virtual pedestrian environments, one delivered by smartphone and the other a semi-immersive kiosk virtual environment. Participants completed self-report measures of perceived realism and simulator sickness experienced in each virtual environment, plus self-reported demographic and personality characteristics. All participants followed system instructions and used the smartphone-based virtual environment without difficulty. No significant simulator sickness was reported or observed. Users rated the smartphone virtual environment as highly realistic. Convergent validity was detected, with many aspects of pedestrian behavior in the smartphone-based virtual environment matching behavior in the kiosk virtual environment. Anticipated correlations between personality and kiosk virtual reality pedestrian behavior emerged for the smartphone-based system. A smartphone-based virtual environment can be usable and valid. Future research should develop and evaluate such a training system.
A GIS application for assessing, mapping, and quantifying the social values of ecosystem services
Sherrouse, Benson C.; Clement, Jessica M.; Semmens, Darius J.
2011-01-01
As human pressures on ecosystems continue to increase, research involving the effective incorporation of social values information into the context of comprehensive ecosystem services assessments is becoming more important. Including quantified, spatially explicit social value metrics in such assessments will improve the analysis of relative tradeoffs among ecosystem services. This paper describes a GIS application, Social Values for Ecosystem Services (SolVES), developed to assess, map, and quantify the perceived social values of ecosystem services by deriving a non-monetary Value Index from responses to a public attitude and preference survey. SolVES calculates and maps the Value Index for social values held by various survey subgroups, as distinguished by their attitudes regarding ecosystem use. Index values can be compared within and among survey subgroups to explore the effect of social contexts on the valuation of ecosystem services. Index values can also be correlated and regressed against landscape metrics SolVES calculates from various environmental data layers. Coefficients derived through these analyses were applied to their corresponding data layers to generate a predicted social value map. This map compared favorably with other SolVES output and led to the addition of a predictive mapping function to SolVES for value transfer to areas where survey data are unavailable. A more robust application is being developed as a public domain tool for decision makers and researchers to map social values of ecosystem services and to facilitate discussions among diverse stakeholders involving relative tradeoffs among different ecosystem services in a variety of physical and social contexts.
Kallesen, Molly; Psirides, Alex; Huckabee, Maggie-Lee
2016-06-01
Orotracheal intubation is known to impair cough reflex, but the validity of cough reflex testing (CRT) as a screening tool for silent aspiration in this population is unknown. One hundred and six participants in a tertiary-level intensive care unit (ICU) underwent CRT and videoendoscopic evaluation of swallowing (VES) within 24 hours of extubation. Cough reflex threshold was established for each participant using nebulized citric acid. Thirty-nine (37%) participants had an absent cough to CRT. Thirteen (12%) participants aspirated on VES, 9 (69%) without a cough response. Sensitivity of CRT to identify silent aspiration was excellent, but specificity was poor. There was a significant correlation between intubation duration and presence of aspiration on VES (P= .0107). There was no significant correlation between silent aspiration on VES and length of intubation, age, sex, diagnosis at intensive care unit admission, indication for intubation, Acute Physiology and Chronic Health Evaluation III score, morphine equivalent dose, or time of testing postextubation. Intensive care unit patients are at increased risk of aspiration in the 24 hours following extubation, and an impaired cough reflex is common. However, CRT overidentifies risk of silent aspiration in this population. Copyright © 2016 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Gilford, J.; Falconer, R. E.; Wade, R.; Scott-Brown, K. C.
2014-09-01
Interactive Virtual Environments (VEs) have the potential to increase student interest in soil science. Accordingly a bespoke 'soil atlas' was created using Java3D as an interactive 3D VE, to show soil information in the context of (and as affected by) the over-lying landscape. To display the below-ground soil characteristics, four sets of artistic illustrations were produced, each set showing the effects of soil organic-matter density and water content on fungal density, to determine potential for visualisations and interactivity in stimulating interest in soil and soil illustrations, interest being an important factor in facilitating learning. The illustrations were created using 3D modelling packages, and a wide range of styles were produced. This allowed a preliminary study of the relative merits of different artistic styles, scientific-credibility, scale, abstraction and 'realism' (e.g. photo-realism or realism of forms), and any relationship between these and the level of interest indicated by the study participants in the soil visualisations and VE. The study found significant differences in mean interest ratings for different soil illustration styles, as well as in the perception of scientific-credibility of these styles, albeit for both measures there was considerable difference of attitude between participants about particular styles. There was also found to be a highly significant positive correlation between participants rating styles highly for interest and highly for scientific-credibility. There was furthermore a particularly high interest rating among participants for seeing temporal soil processes illustrated/animated, suggesting this as a particularly promising method for further stimulating interest in soil illustrations and soil itself.
ERIC Educational Resources Information Center
Aitken, Liz; Chadwick, Arthur; Hughes, Maria
2006-01-01
Centres of Vocational Excellence (CoVEs) were established in 2001, intended to be a key driver in enhancing the contribution of the further education (FE) sector to meeting skills needs. Current government policy expects employers and individuals to pay a greater share of the costs of training, particularly at Level 3, which is the CoVE priority…
Soubeyran, Pierre; Bellera, Carine; Goyard, Jean; Heitz, Damien; Curé, Hervé; Rousselot, Hubert; Albrand, Gilles; Servent, Véronique; Jean, Olivier Saint; van Praagh, Isabelle; Kurtz, Jean-Emmanuel; Périn, Stéphane; Verhaeghe, Jean-Luc; Terret, Catherine; Desauw, Christophe; Girre, Véronique; Mertens, Cécile; Mathoulin-Pélissier, Simone; Rainfray, Muriel
2014-01-01
Background Geriatric Assessment is an appropriate method for identifying older cancer patients at risk of life-threatening events during therapy. Yet, it is underused in practice, mainly because it is time- and resource-consuming. This study aims to identify the best screening tool to identify older cancer patients requiring geriatric assessment by comparing the performance of two short assessment tools the G8 and the Vulnerable Elders Survey (VES-13). Patients and Methods The diagnostic accuracy of the G8 and the (VES-13) were evaluated in a prospective cohort study of 1674 cancer patients accrued before treatment in 23 health care facilities. 1435 were eligible and evaluable. Outcome measures were multidimensional geriatric assessment (MGA), sensitivity (primary), specificity, negative and positive predictive values and likelihood ratios of the G8 and VES-13, and predictive factors of 1-year survival rate. Results Patient median age was 78.2 years (70-98) with a majority of females (69.8%), various types of cancer including 53.9% breast, and 75.8% Performance Status 0-1. Impaired MGA, G8, and VES-13 were 80.2%, 68.4%, and 60.2%, respectively. Mean time to complete G8 or VES-13 was about five minutes. Reproducibility of the two questionnaires was good. G8 appeared more sensitive (76.5% versus 68.7%, P = 0.0046) whereas VES-13 was more specific (74.3% versus 64.4%, P<0.0001). Abnormal G8 score (HR = 2.72), advanced stage (HR = 3.30), male sex (HR = 2.69) and poor Performance Status (HR = 3.28) were independent prognostic factors of 1-year survival. Conclusion With good sensitivity and independent prognostic value on 1-year survival, the G8 questionnaire is currently one of the best screening tools available to identify older cancer patients requiring geriatric assessment, and we believe it should be implemented broadly in daily practice. Continuous research efforts should be pursued to refine the selection process of older cancer patients before potentially life-threatening therapy. PMID:25503576
Colhoun, Andrew F; Speich, John E; Cooley, Lauren F; Bell, Eugene D; Barbee, R Wayne; Guruli, Georgi; Ratz, Paul H; Klausner, Adam P
2017-08-01
Low amplitude rhythmic contractions (LARC) occur in detrusor smooth muscle and may play a role in storage disorders such as overactive bladder and detrusor overactivity. The purpose of this study was to determine whether LARC frequencies identified in vitro from strips of human urinary bladder tissue correlate with in vivo LARC frequencies, visualized as phasic intravesical pressure (p ves ) waves during urodynamics (UD). After IRB approval, fresh strips of human urinary bladder were obtained from patients. LARC was recorded with tissue strips at low tension (<2 g) and analyzed by fast Fourier transform (FFT) to identify LARC signal frequencies. Blinded UD tracings were retrospectively reviewed for signs of LARC on the p ves tracing during filling and were analyzed via FFT. Distinct LARC frequencies were identified in 100% of tissue strips (n = 9) obtained with a mean frequency of 1.97 ± 0.47 cycles/min (33 ± 8 mHz). Out of 100 consecutive UD studies reviewed, 35 visually displayed phasic p ves waves. In 12/35 (34%), real p ves signals were present that were independent of abdominal activity. Average UD LARC frequency was 2.34 ± 0.36 cycles/min (39 ± 6 mHz) which was similar to tissue LARC frequencies (p = 0.50). A majority (83%) of the UD cohort with LARC signals also demonstrated detrusor overactivity. During UD, a subset of patients displayed phasic p ves waves with a distinct rhythmic frequency similar to the in vitro LARC frequency quantified in human urinary bladder tissue strips. Further refinements of this technique may help identify subsets of individuals with LARC-mediated storage disorders.
[Cross reactions between Hymenoptera venoms from different families, genera and species].
Hemmer, W
2014-09-01
Simultaneous reactivity with the venoms of different Hymenoptera is commonly seen in patients allergic to insect venoms. Strong, though individually variable, cross-reactivity occurs between the venoms of different Vespinae species (Vespula, Dolichovespula, Vespa). In Middle Europe, anaphylaxis after European hornet stings is nearly always due to cross-reactivity with Vespula venom. The identification of the primary venom in patients testing positive for Vespula and Polistes (paper wasps) is particularly important in Mediterranean areas. Component-resolved diagnosis with the marker allergens Ves v 5 and Pol d 5 may directly identify the causative venom in the majority of patients. There is substantial cross-reactivity between honeybee and bumblebee venom, sometimes causing allergic symptoms in patients allergic to honeybee venom after accidental bumblebee stings. However, subjects strongly exposed to bumblebees may show bumblebee-specific sensitization and require immunotherapy with bumblebee venom. More than half of all venom-allergic patients show double-positive test results to honeybee and vespid venoms. This may be due to true double sensitization or due to cross-reactivity between homologous allergens present in both venoms and sharing around 50 % sequence identity, i.e. hyaluronidases (Api m 2/Ves v 2), dipeptidyl peptidases (Api m 5/Ves v 3), and vitellogenins (Api m 12/Ves v 6). The clinical relevance of these cross-reactions is unknown. In up to 50 % the double-positivity is caused by clinically irrelevant IgE antibodies against CCDs. Many (though not all) patients with true double sensitization may be identified by means of the species-specific marker allergens Api m 1 and Ves v 1/5. Some Vespula venom-allergic patients may clinically cross-react to fire ant stings (Solenopsis), but otherwise allergen relationships with other ant species are not well studied.
Bidirectional Cardio-Respiratory Interactions in Heart Failure.
Radovanović, Nikola N; Pavlović, Siniša U; Milašinović, Goran; Kirćanski, Bratislav; Platiša, Mirjana M
2018-01-01
We investigated cardio-respiratory coupling in patients with heart failure by quantification of bidirectional interactions between cardiac (RR intervals) and respiratory signals with complementary measures of time series analysis. Heart failure patients were divided into three groups of twenty, age and gender matched, subjects: with sinus rhythm (HF-Sin), with sinus rhythm and ventricular extrasystoles (HF-VES), and with permanent atrial fibrillation (HF-AF). We included patients with indication for implantation of implantable cardioverter defibrillator or cardiac resynchronization therapy device. ECG and respiratory signals were simultaneously acquired during 20 min in supine position at spontaneous breathing frequency in 20 healthy control subjects and in patients before device implantation. We used coherence, Granger causality and cross-sample entropy analysis as complementary measures of bidirectional interactions between RR intervals and respiratory rhythm. In heart failure patients with arrhythmias (HF-VES and HF-AF) there is no coherence between signals ( p < 0.01), while in HF-Sin it is reduced ( p < 0.05), compared with control subjects. In all heart failure groups causality between signals is diminished, but with significantly stronger causality of RR signal in respiratory signal in HF-VES. Cross-sample entropy analysis revealed the strongest synchrony between respiratory and RR signal in HF-VES group. Beside respiratory sinus arrhythmia there is another type of cardio-respiratory interaction based on the synchrony between cardiac and respiratory rhythm. Both of them are altered in heart failure patients. Respiratory sinus arrhythmia is reduced in HF-Sin patients and vanished in heart failure patients with arrhythmias. Contrary, in HF-Sin and HF-VES groups, synchrony increased, probably as consequence of some dominant neural compensatory mechanisms. The coupling of cardiac and respiratory rhythm in heart failure patients varies depending on the presence of atrial/ventricular arrhythmias and it could be revealed by complementary methods of time series analysis.
ERIC Educational Resources Information Center
Williams, Ruth; Yarrow, Karen
2006-01-01
Centres of Vocational Excellence (CoVEs) deliver specialist vocational provision with a focus on increasing learner numbers at Level 3. They aim to produce skilled and appropriately qualified workers to meet the needs of the economy by enhancing the skills and careers of those already in work, the employability of new entrants to the labor …
NASA Astrophysics Data System (ADS)
Bayewu, Olateju O.; Oloruntola, Moroof O.; Mosuro, Ganiyu O.; Laniyan, Temitope A.; Ariyo, Stephen O.; Fatoba, Julius O.
2017-12-01
The geophysical assessment of groundwater in Awa-Ilaporu, near Ago Iwoye southwestern Nigeria was carried out with the aim of delineating probable areas of high groundwater potential. The area falls within the Crystalline Basement Complex of southwestern Nigeria which is predominantly underlain by banded gneiss, granite gneiss and pegmatite. The geophysical investigation involves the very low frequency electromagnetic (VLF-EM) and Vertical Electrical Sounding (VES) methods. The VLF-EM survey was at 10 m interval along eight traverses ranging between 290 and 700 m in length using ABEM WADI VLF-EM unit. The VLF-EM survey was used to delineate areas with conductive/fractured zones. Twenty-three VES surveys were carried out with the use of Campus Ohmega resistivity meter at different location and at locations areas delineated as high conductive areas by VLF-EM survey. The result of VLF-EM survey along its traverse was used in delineating high conductive/fractured zones, it is, however, in agreement with the delineation of the VES survey. The VES results showed 3-4 geoelectric layers inferred as sandy topsoil, sandy clay, clayey and fractured/fresh basement. The combination of these two methods, therefore, helped in resolving the prospecting location for the groundwater yield in the study area.
Quadrado, Virgínia Helena; Silva, Talita Dias da; Favero, Francis Meire; Tonks, James; Massetti, Thais; Monteiro, Carlos Bandeira de Mello
2017-11-10
To examine whether performance improvements in the virtual environment generalize to the natural environment. we had 64 individuals, 32 of which were individuals with DMD and 32 were typically developing individuals. The groups practiced two coincidence timing tasks. In the more tangible button-press task, the individuals were required to 'intercept' a falling virtual object at the moment it reached the interception point by pressing a key on the computer. In the more abstract task, they were instructed to 'intercept' the virtual object by making a hand movement in a virtual environment using a webcam. For individuals with DMD, conducting a coincidence timing task in a virtual environment facilitated transfer to the real environment. However, we emphasize that a task practiced in a virtual environment should have higher rates of difficulties than a task practiced in a real environment. IMPLICATIONS FOR REHABILITATION Virtual environments can be used to promote improved performance in ?real-world? environments. Virtual environments offer the opportunity to create paradigms similar ?real-life? tasks, however task complexity and difficulty levels can be manipulated, graded and enhanced to increase likelihood of success in transfer of learning and performance. Individuals with DMD, in particular, showed immediate performance benefits after using virtual reality.
Shared virtual environments for aerospace training
NASA Technical Reports Server (NTRS)
Loftin, R. Bowen; Voss, Mark
1994-01-01
Virtual environments have the potential to significantly enhance the training of NASA astronauts and ground-based personnel for a variety of activities. A critical requirement is the need to share virtual environments, in real or near real time, between remote sites. It has been hypothesized that the training of international astronaut crews could be done more cheaply and effectively by utilizing such shared virtual environments in the early stages of mission preparation. The Software Technology Branch at NASA's Johnson Space Center has developed the capability for multiple users to simultaneously share the same virtual environment. Each user generates the graphics needed to create the virtual environment. All changes of object position and state are communicated to all users so that each virtual environment maintains its 'currency.' Examples of these shared environments will be discussed and plans for the utilization of the Department of Defense's Distributed Interactive Simulation (DIS) protocols for shared virtual environments will be presented. Finally, the impact of this technology on training and education in general will be explored.
The specificity of memory enhancement during interaction with a virtual environment.
Brooks, B M; Attree, E A; Rose, F D; Clifford, B R; Leadbetter, A G
1999-01-01
Two experiments investigated differences between active and passive participation in a computer-generated virtual environment in terms of spatial memory, object memory, and object location memory. It was found that active participants, who controlled their movements in the virtual environment using a joystick, recalled the spatial layout of the virtual environment better than passive participants, who merely watched the active participants' progress. Conversely, there were no significant differences between the active and passive participants' recall or recognition of the virtual objects, nor in their recall of the correct locations of objects in the virtual environment. These findings are discussed in terms of subject-performed task research and the specificity of memory enhancement in virtual environments.
Component-resolved diagnosis in hymenoptera allergy.
Antolín-Amérigo, D; Ruiz-León, B; Boni, E; Alfaya-Arias, T; Álvarez-Mon, M; Barbarroja-Escudero, J; González-de-Olano, D; Moreno-Aguilar, C; Rodríguez-Rodríguez, M; Sánchez-González, M J; Sánchez-Morillas, L; Vega-Castro, A
Component-resolved diagnosis based on the use of well-defined, properly characterised and purified natural and recombinant allergens constitutes a new approach in the diagnosis of venom allergy. Prospective readers may benefit from an up-to-date review on the allergens. The best characterised venom is that of Apis mellifera, whose main allergens are phospholipase A2 (Api m1), hyaluronidase (Api m2) and melittin (Api m4). Additionally, in recent years, new allergens of Vespula vulgaris have been identified and include phospholipase A1 (Ves v1), hyaluronidase (Ves v2) and antigen 5 (Ves v5). Polistes species are becoming an increasing cause of allergy in Europe, although only few allergens have been identified in this venom. In this review, we evaluate the current knowledge about molecular diagnosis in hymenoptera venom allergy. Copyright © 2017 SEICAP. Published by Elsevier España, S.L.U. All rights reserved.
[Values of marine ecosystem services in Sanggou Bay].
Zhang, Zhao-hui; Lü, Ji-bin; Ye, Shu-feng; Zhu, Ming-yuan
2007-11-01
A valuation study was conducted in Sanggou Bay, a typical and intensive coastal aquaculture area in China Yellow Sea. The results showed that the total value of ecosystem services (VES) in Sanggou Bay was 6.07 x 10(8) Yen in 2003, with an average unit VES being 4.24 x 10(6) Yen x km(-2). Within the total VES, the provision services, regulation services, and culture services accounted for 51.29%, 17.34%, and 31.37%, respectively. Among the eight primary and secondary services valuated in Sanggou Bay, food provision services held the highest value (50.45%), followed by tourism and entertainment services (29.89%) and climate regulation services (9.18%). Harmful organism and disease control services have the lowest value (0.0017%). The aquaculture activities had greater contributions to the local social economy, environmental regulation, and social culture. Aquaculture activities, especially macro-algae farming, are of significance in maintaining and enhancing the ecosystem services.
Validation of virtual reality as a tool to understand and prevent child pedestrian injury.
Schwebel, David C; Gaines, Joanna; Severson, Joan
2008-07-01
In recent years, virtual reality has emerged as an innovative tool for health-related education and training. Among the many benefits of virtual reality is the opportunity for novice users to engage unsupervised in a safe environment when the real environment might be dangerous. Virtual environments are only useful for health-related research, however, if behavior in the virtual world validly matches behavior in the real world. This study was designed to test the validity of an immersive, interactive virtual pedestrian environment. A sample of 102 children and 74 adults was recruited to complete simulated road-crossings in both the virtual environment and the identical real environment. In both the child and adult samples, construct validity was demonstrated via significant correlations between behavior in the virtual and real worlds. Results also indicate construct validity through developmental differences in behavior; convergent validity by showing correlations between parent-reported child temperament and behavior in the virtual world; internal reliability of various measures of pedestrian safety in the virtual world; and face validity, as measured by users' self-reported perception of realism in the virtual world. We discuss issues of generalizability to other virtual environments, and the implications for application of virtual reality to understanding and preventing pediatric pedestrian injuries.
An Audio Architecture Integrating Sound and Live Voice for Virtual Environments
2002-09-01
implementation of a virtual environment. As real world training locations become scarce and training budgets are trimmed, training system developers ...look more and more towards virtual environments as the answer. Virtual environments provide training system developers with several key benefits
Realistic terrain visualization based on 3D virtual world technology
NASA Astrophysics Data System (ADS)
Huang, Fengru; Lin, Hui; Chen, Bin; Xiao, Cai
2009-09-01
The rapid advances in information technologies, e.g., network, graphics processing, and virtual world, have provided challenges and opportunities for new capabilities in information systems, Internet applications, and virtual geographic environments, especially geographic visualization and collaboration. In order to achieve meaningful geographic capabilities, we need to explore and understand how these technologies can be used to construct virtual geographic environments to help to engage geographic research. The generation of three-dimensional (3D) terrain plays an important part in geographical visualization, computer simulation, and virtual geographic environment applications. The paper introduces concepts and technologies of virtual worlds and virtual geographic environments, explores integration of realistic terrain and other geographic objects and phenomena of natural geographic environment based on SL/OpenSim virtual world technologies. Realistic 3D terrain visualization is a foundation of construction of a mirror world or a sand box model of the earth landscape and geographic environment. The capabilities of interaction and collaboration on geographic information are discussed as well. Further virtual geographic applications can be developed based on the foundation work of realistic terrain visualization in virtual environments.
Realistic terrain visualization based on 3D virtual world technology
NASA Astrophysics Data System (ADS)
Huang, Fengru; Lin, Hui; Chen, Bin; Xiao, Cai
2010-11-01
The rapid advances in information technologies, e.g., network, graphics processing, and virtual world, have provided challenges and opportunities for new capabilities in information systems, Internet applications, and virtual geographic environments, especially geographic visualization and collaboration. In order to achieve meaningful geographic capabilities, we need to explore and understand how these technologies can be used to construct virtual geographic environments to help to engage geographic research. The generation of three-dimensional (3D) terrain plays an important part in geographical visualization, computer simulation, and virtual geographic environment applications. The paper introduces concepts and technologies of virtual worlds and virtual geographic environments, explores integration of realistic terrain and other geographic objects and phenomena of natural geographic environment based on SL/OpenSim virtual world technologies. Realistic 3D terrain visualization is a foundation of construction of a mirror world or a sand box model of the earth landscape and geographic environment. The capabilities of interaction and collaboration on geographic information are discussed as well. Further virtual geographic applications can be developed based on the foundation work of realistic terrain visualization in virtual environments.
Maidenbaum, Shachar; Levy-Tzedek, Shelly; Chebat, Daniel-Robert; Amedi, Amir
2013-01-01
Virtual worlds and environments are becoming an increasingly central part of our lives, yet they are still far from accessible to the blind. This is especially unfortunate as such environments hold great potential for them for uses such as social interaction, online education and especially for use with familiarizing the visually impaired user with a real environment virtually from the comfort and safety of his own home before visiting it in the real world. We have implemented a simple algorithm to improve this situation using single-point depth information, enabling the blind to use a virtual cane, modeled on the “EyeCane” electronic travel aid, within any virtual environment with minimal pre-processing. Use of the Virtual-EyeCane, enables this experience to potentially be later used in real world environments with identical stimuli to those from the virtual environment. We show the fast-learned practical use of this algorithm for navigation in simple environments. PMID:23977316
MERIANS, Alma S.; TUNIK, Eugene; ADAMOVICH, Sergei V.
2015-01-01
Stroke patients report hand function as the most disabling motor deficit. Current evidence shows that learning new motor skills is essential for inducing functional neuroplasticity and functional recovery. Adaptive training paradigms that continually and interactively move a motor outcome closer to the targeted skill are important to motor recovery. Computerized virtual reality simulations when interfaced with robots, movement tracking and sensing glove systems are particularly adaptable, allowing for online and offline modifications of task based activities using the participant’s current performance and success rate. We have developed a second generation system that can exercise the hand and the arm together or in isolation and provides for both unilateral and bilateral hand and arm activities in three-dimensional space. We demonstrate that by providing haptic assistance for the hand and arm and adaptive anti-gravity support, the system can accommodate patients with lower level impairments. We hypothesize that combining training in VE with observation of motor actions can bring additional benefits. We present a proof of concept of a novel system that integrates interactive VE with functional neuroimaging to address this issue. Three components of this system are synchronized, the presentation of the visual display of the virtual hands, the collection of fMRI images and the collection of hand joint angles from the instrumented gloves. We show that interactive VEs can facilitate activation of brain areas during training by providing appropriately modified visual feedback. We predict that visual augmentation can become a tool to facilitate functional neuroplasticity. PMID:19592790
G2H--graphics-to-haptic virtual environment development tool for PC's.
Acosta, E; Temkin, B; Krummel, T M; Heinrichs, W L
2000-01-01
For surgical training and preparations, the existing surgical virtual environments have shown great improvement. However, these improvements are more in the visual aspect. The incorporation of haptics into virtual reality base surgical simulations would enhance the sense of realism greatly. To aid in the development of the haptic surgical virtual environment we have created a graphics to haptic, G2H, virtual environment developer tool. G2H transforms graphical virtual environments (created or imported) to haptic virtual environments without programming. The G2H capability has been demonstrated using the complex 3D pelvic model of Lucy 2.0, the Stanford Visible Female. The pelvis was made haptic using G2H without any further programming effort.
Grasping trajectories in a virtual environment adhere to Weber's law.
Ozana, Aviad; Berman, Sigal; Ganel, Tzvi
2018-06-01
Virtual-reality and telerobotic devices simulate local motor control of virtual objects within computerized environments. Here, we explored grasping kinematics within a virtual environment and tested whether, as in normal 3D grasping, trajectories in the virtual environment are performed analytically, violating Weber's law with respect to object's size. Participants were asked to grasp a series of 2D objects using a haptic system, which projected their movements to a virtual space presented on a computer screen. The apparatus also provided object-specific haptic information upon "touching" the edges of the virtual targets. The results showed that grasping movements performed within the virtual environment did not produce the typical analytical trajectory pattern obtained during 3D grasping. Unlike as in 3D grasping, grasping trajectories in the virtual environment adhered to Weber's law, which indicates relative resolution in size processing. In addition, the trajectory patterns differed from typical trajectories obtained during 3D grasping, with longer times to complete the movement, and with maximum grip apertures appearing relatively early in the movement. The results suggest that grasping movements within a virtual environment could differ from those performed in real space, and are subjected to irrelevant effects of perceptual information. Such atypical pattern of visuomotor control may be mediated by the lack of complete transparency between the interface and the virtual environment in terms of the provided visual and haptic feedback. Possible implications of the findings to movement control within robotic and virtual environments are further discussed.
ERIC Educational Resources Information Center
Cheng, Yufang; Huang, Ruowen
2012-01-01
The focus of this study is using data glove to practice Joint attention skill in virtual reality environment for people with pervasive developmental disorder (PDD). The virtual reality environment provides a safe environment for PDD people. Especially, when they made errors during practice in virtual reality environment, there is no suffering or…
Intelligent Motion and Interaction Within Virtual Environments
NASA Technical Reports Server (NTRS)
Ellis, Stephen R. (Editor); Slater, Mel (Editor); Alexander, Thomas (Editor)
2007-01-01
What makes virtual actors and objects in virtual environments seem real? How can the illusion of their reality be supported? What sorts of training or user-interface applications benefit from realistic user-environment interactions? These are some of the central questions that designers of virtual environments face. To be sure simulation realism is not necessarily the major, or even a required goal, of a virtual environment intended to communicate specific information. But for some applications in entertainment, marketing, or aspects of vehicle simulation training, realism is essential. The following chapters will examine how a sense of truly interacting with dynamic, intelligent agents may arise in users of virtual environments. These chapters are based on presentations at the London conference on Intelligent Motion and Interaction within a Virtual Environments which was held at University College, London, U.K., 15-17 September 2003.
ERIC Educational Resources Information Center
O'Connor, Eileen A.; Domingo, Jelia
2017-01-01
With the advent of open source virtual environments, the associated cost reductions, and the more flexible options, avatar-based virtual reality environments are within reach of educators. By using and repurposing readily available virtual environments, instructors can bring engaging, community-building, and immersive learning opportunities to…
Coercive Narratives, Motivation and Role Playing in Virtual Worlds
2002-01-01
resource for making immersive virtual environments highly engaging. Interaction also appeals to our natural desire to discover. Reading a book contains...participation in an open-ended Virtual Environment (VE). I intend to take advantage of a participants’ natural tendency to prefer interaction when possible...I hope this work will expand the potential of experience within virtual worlds. K e y w o r d s : Immersive Environments , Virtual Environments
Myer, Landon; Dunning, Lorna; Lesosky, Maia; Hsiao, Nei-Yuan; Phillips, Tamsin; Petro, Greg; Zerbe, Allison; McIntyre, James A; Abrams, Elaine J
2017-02-15
The numbers of human immunodeficiency virus (HIV)-infected women initiating antiretroviral therapy (ART) in pregnancy are increasing rapidly with global policy changes. There are widespread concerns about ART adherence during pregnancy and postpartum but few data on viral suppression (VS) over time in these populations. We followed a cohort of 523 women in Cape Town, South Africa, initiating ART in pregnancy (once-daily tenofovir 300 mg, emtricitabine 200 mg, and efavirenz 600 mg) and achieving VS (<50 copies/mL). Participants provided specimens through 12 months postpartum for batched viral load (VL) testing separate from routine care. Analyses described the incidence of major (>1000 copies/mL) and minor (50-1000 copies/mL) viremic episodes (VEs) and factors associated with major VEs. In the cohort (median age, 28 years; median pre-ART VL, 3.99 copies/mL; 3% previously defaulted ART; 24% with previous exposure to short-course antiretrovirals), the median time of follow-up from VS was 322 days. Overall, 70% maintained VS throughout follow-up, 8% experienced minor VEs only, and at least 1 major VE was documented in 22% of women. In women with VEs, peak viremia (median, 3.79 log10 copies/mL) was linearly related to pre-ART VL. The incidence of major VEs after initial VS was independently associated with younger age, ART initiation during the third trimester, previous defaulting on ART, and postpartum follow-up. Viremia appears to occur frequently, particularly postpartum, among HIV-infected women after initial VS in this setting. More intensive VL monitoring is warranted in this population; the immediate causes and long-term implications of VE require investigation. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.
Vogt, Tobias; Herpers, Rainer; Askew, Christopher D.; Scherfgen, David; Strüder, Heiko K.; Schneider, Stefan
2015-01-01
Virtual reality environments are increasingly being used to encourage individuals to exercise more regularly, including as part of treatment those with mental health or neurological disorders. The success of virtual environments likely depends on whether a sense of presence can be established, where participants become fully immersed in the virtual environment. Exposure to virtual environments is associated with physiological responses, including cortical activation changes. Whether the addition of a real exercise within a virtual environment alters sense of presence perception, or the accompanying physiological changes, is not known. In a randomized and controlled study design, moderate-intensity Exercise (i.e., self-paced cycling) and No-Exercise (i.e., automatic propulsion) trials were performed within three levels of virtual environment exposure. Each trial was 5 minutes in duration and was followed by posttrial assessments of heart rate, perceived sense of presence, EEG, and mental state. Changes in psychological strain and physical state were generally mirrored by neural activation patterns. Furthermore, these changes indicated that exercise augments the demands of virtual environment exposures and this likely contributed to an enhanced sense of presence. PMID:26366305
Vogt, Tobias; Herpers, Rainer; Askew, Christopher D; Scherfgen, David; Strüder, Heiko K; Schneider, Stefan
2015-01-01
Virtual reality environments are increasingly being used to encourage individuals to exercise more regularly, including as part of treatment those with mental health or neurological disorders. The success of virtual environments likely depends on whether a sense of presence can be established, where participants become fully immersed in the virtual environment. Exposure to virtual environments is associated with physiological responses, including cortical activation changes. Whether the addition of a real exercise within a virtual environment alters sense of presence perception, or the accompanying physiological changes, is not known. In a randomized and controlled study design, moderate-intensity Exercise (i.e., self-paced cycling) and No-Exercise (i.e., automatic propulsion) trials were performed within three levels of virtual environment exposure. Each trial was 5 minutes in duration and was followed by posttrial assessments of heart rate, perceived sense of presence, EEG, and mental state. Changes in psychological strain and physical state were generally mirrored by neural activation patterns. Furthermore, these changes indicated that exercise augments the demands of virtual environment exposures and this likely contributed to an enhanced sense of presence.
ERIC Educational Resources Information Center
Jiman, Juhanita
This paper discusses the use of Virtual Reality (VR) in e-learning environments where an intelligent three-dimensional (3D) virtual person plays the role of an instructor. With the existence of this virtual instructor, it is hoped that the teaching and learning in the e-environment will be more effective and productive. This virtual 3D animated…
Cybersickness and Anxiety During Simulated Motion: Implications for VRET.
Bruck, Susan; Watters, Paul
2009-01-01
Some clinicians have suggested using virtual reality environments to deliver psychological interventions to treat anxiety disorders. However, given a significant body of work on cybersickness symptoms which may arise in virtual environments - especially those involving simulated motion - we tested (a) whether being exposed to a virtual reality environment alone causes anxiety to increase, and (b) whether exposure to simulated motion in a virtual reality environment increases anxiety. Using a repeated measures design, we used Kim's Anxiety Scale questionnaire to compare baseline anxiety, anxiety after virtual environment exposure, and anxiety after simulated motion. While there was no significant effect on anxiety for being in a virtual environment with no simulated motion, the introduction of simulated motion caused anxiety to significantly increase, but not to a severe or extreme level. The implications of this work for virtual reality exposure therapy (VRET) are discussed.
2-D inversion of VES data in Saqqara archaeological area, Egypt
NASA Astrophysics Data System (ADS)
El-Qady, Gad; Sakamoto, Chika; Ushijima, Keisuke
1999-10-01
The interpretation of actual geophysical field data still has a problem for obtaining a unique solution. In order to investigate the groundwater potentials in Saqqara archaeological area, vertical electrical soundings with Schlumberger array have been carried out. In the interpretation of VES data, 1D resistivity inversion has been performed based on a horizontally layered earth model by El-Qady (1995). However, some results of 1D inversion are not fully satisfied for actual 3D structures such as archaeological tombs. Therefore, we have carried out 2D inversion based on ABIC least squares method for Schlumberger VES data obtained in Saqqara area. Although the results of 2D cross sections were correlated with the previous interpretation, the 2D inversion still shows a rough spatial resistivity distribution, which is the abrupt change in resistivity between two neighboring blocks of the computed region. It is concluded that 3D interpretation is recommended for visualizing ground water distribution with depth in the Saqqara area.
Virtual Education: Guidelines for Using Games Technology
ERIC Educational Resources Information Center
Schofield, Damian
2014-01-01
Advanced three-dimensional virtual environment technology, similar to that used by the film and computer games industry, can allow educational developers to rapidly create realistic online virtual environments. This technology has been used to generate a range of interactive Virtual Reality (VR) learning environments across a spectrum of…
Reaction time for processing visual stimulus in a computer-assisted rehabilitation environment.
Sanchez, Yerly; Pinzon, David; Zheng, Bin
2017-10-01
To examine the reaction time when human subjects process information presented in the visual channel under both a direct vision and a virtual rehabilitation environment when walking was performed. Visual stimulus included eight math problems displayed on the peripheral vision to seven healthy human subjects in a virtual rehabilitation training (computer-assisted rehabilitation environment (CAREN)) and a direct vision environment. Subjects were required to verbally report the results of these math calculations in a short period of time. Reaction time measured by Tobii Eye tracker and calculation accuracy were recorded and compared between the direct vision and virtual rehabilitation environment. Performance outcomes measured for both groups included reaction time, reading time, answering time and the verbal answer score. A significant difference between the groups was only found for the reaction time (p = .004). Participants had more difficulty recognizing the first equation of the virtual environment. Participants reaction time was faster in the direct vision environment. This reaction time delay should be kept in mind when designing skill training scenarios in virtual environments. This was a pilot project to a series of studies assessing cognition ability of stroke patients who are undertaking a rehabilitation program with a virtual training environment. Implications for rehabilitation Eye tracking is a reliable tool that can be employed in rehabilitation virtual environments. Reaction time changes between direct vision and virtual environment.
NASA Astrophysics Data System (ADS)
Ribeiro, Eduardo Afonso; Lopes, Eduardo Márcio de Oliveira; Bavastri, Carlos Alberto
2017-12-01
Viscoelastic materials have played an important role in passive vibration control. Nevertheless, the use of such materials in supports of rotating machines, aiming at controlling vibration, is more recent, mainly when these supports present additional complexities like multiple degrees of freedom and require accurate models to predict the dynamic behavior of viscoelastic materials working in a broad band of frequencies and temperatures. Previously, the authors propose a methodology for an optimal design of viscoelastic supports (VES) for vibration suppression in rotordynamics, which improves the dynamic prediction accuracy, the speed calculation, and the modeling of VES as complex structures. However, a comprehensive numerical study of the dynamics of rotor-VES systems, regarding the types and combinations of translational and rotational degrees of freedom (DOFs), accompanied by the corresponding experimental validation, is still lacking. This paper presents such a study considering different types and combinations of DOFs in addition to the simulation of their number of additional masses/inertias, as well as the kind and association of the applied viscoelastic materials (VEMs). The results - regarding unbalance frequency response, transmissibility and displacement due to static loads - lead to: 1) considering VES as complex structures which allow improving the efficacy in passive vibration control; 2) acknowledging the best configuration concerning DOFs and VEM choice and association for a practical application concerning passive vibration control and load resistance. The specific outcomes of the conducted experimental validation attest the accuracy of the proposed methodology.
NASA Astrophysics Data System (ADS)
Mesbah, Hany S.; Morsy, Essam A.; Soliman, Mamdouh M.; Kabeel, Khamis
2017-06-01
This paper presents the results of the application of the Geoelectrical Resistivity Sounding (GRS) and Ground Penetrating Radar (GPR) for outlining and investigating of surface springing out (flow) of groundwater to the base of an service building site, and determining the reason(s) for the zone of maximum degree of saturation; in addition to provide stratigraphic information for this site. The studied economic building is constructed lower than the ground surface by about 7 m. A Vertical Electrical Sounding (VES) survey was performed at 12 points around the studied building in order to investigate the vertical and lateral extent of the subsurface sequence, three VES's were conducted at each side of the building at discrete distances. And a total of 9 GPR profiles with 100- and 200-MHz antennae were conducted, with the objective of evaluating the depth and the degree of saturation of the subsurface layers. The qualitative and quantitative interpretation of the acquired VES's showed easily the levels of saturations close to and around the studied building. From the interpretation of GPR profiles, it was possible to locate and determine the saturated layers. The radar signals are penetrated and enabled the identification of the subsurface reflectors. The results of GPR and VES showed a good agreement and the integrated interpretations were supported by local geology. Finally, the new constructed geoelectrical resistivity cross-sections (in contoured-form), are easily clarifying the direction of groundwater flow toward the studied building.
NASA Astrophysics Data System (ADS)
Asfahani, Jamal
2016-05-01
A new alternative approach based on using Vertical electrical sounding (VES) technique is proposed for computing the hydraulic conductivity K of an aquifer. The approach takes only the salinity of the groundwater into consideration. VES measurements in the locations, where available water samples exist, are required in such an approach, in order to calibrate and establish empirical relationships between transverse resistance Dar-Zarrouck TR parameter and modified transverse resistance MTR, and between MTR and transmissivity T. Those relationships are thereafter used to extrapolate the transmissivity even in the VES points where no water samples exist. This approach is tested and practiced in the Khanasser valley, Northern Syria, where the hydraulic conductivity of the Quaternary aquifer is computed. An acceptable agreement is found between the hydraulic conductivity values obtained by the proposed approach and those obtained by the pumping test which range between 0.864 and 8.64 m/day (10-5 and 10-4 m/s). The Quaternary aquifer transmissivity of the Khanasser Valley, has been characterized by using this approach and by adapting the MTR parameter. The transmissivity varies between a minimum of 79 m2/day and a maximum of 814 m2/day, with an average of 283 m2/day and a standard deviation of 145 m2/day. The easy and inexpensive approach proposed in this paper can be applied in other semi arid regions.
Brain Activity on Navigation in Virtual Environments.
ERIC Educational Resources Information Center
Mikropoulos, Tassos A.
2001-01-01
Assessed the cognitive processing that takes place in virtual environments by measuring electrical brain activity using Fast Fourier Transform analysis. University students performed the same task in a real and a virtual environment, and eye movement measurements showed that all subjects were more attentive when navigating in the virtual world.…
A Virtual Education: Guidelines for Using Games Technology
ERIC Educational Resources Information Center
Schofield, Damian
2014-01-01
Advanced three-dimensional virtual environment technology, similar to that used by the film and computer games industry, can allow educational developers to rapidly create realistic online vir-tual environments. This technology has been used to generate a range of interactive Virtual Real-ity (VR) learning environments across a spectrum of…
Lee, Jae M; Ku, Jeong H; Jang, Dong P; Kim, Dong H; Choi, Young H; Kim, In Y; Kim, Sun I
2002-06-01
The fear of speaking is often cited as the world's most common social phobia. The rapid growth of computer technology enabled us to use virtual reality (VR) for the treatment of the fear of public speaking. There have been two techniques used to construct a virtual environment for the treatment of the fear of public speaking: model-based and movie-based. Virtual audiences and virtual environments made by model-based technique are unrealistic and unnatural. The movie-based technique has a disadvantage in that each virtual audience cannot be controlled respectively, because all virtual audiences are included in one moving picture file. To address this disadvantage, this paper presents a virtual environment made by using image-based rendering (IBR) and chroma keying simultaneously. IBR enables us to make the virtual environment realistic because the images are stitched panoramically with the photos taken from a digital camera. And the use of chroma keying allows a virtual audience to be controlled individually. In addition, a real-time capture technique was applied in constructing the virtual environment to give the subjects more interaction, in that they can talk with a therapist or another subject.
2017-08-08
Usability Studies In Virtual And Traditional Computer Aided Design Environments For Spatial Awareness Dr. Syed Adeel Ahmed, Xavier University of...virtual environment with wand interfaces compared directly with a workstation non-stereoscopic traditional CAD interface with keyboard and mouse. In...navigate through a virtual environment. The wand interface provides a significantly improved means of interaction. This study quantitatively measures the
A virtual therapeutic environment with user projective agents.
Ookita, S Y; Tokuda, H
2001-02-01
Today, we see the Internet as more than just an information infrastructure, but a socializing place and a safe outlet of inner feelings. Many personalities develop aside from real world life due to its anonymous environment. Virtual world interactions are bringing about new psychological illnesses ranging from netaddiction to technostress, as well as online personality disorders and conflicts in multiple identities that exist in the virtual world. Presently, there are no standard therapy models for the virtual environment. There are very few therapeutic environments, or tools especially made for virtual therapeutic environments. The goal of our research is to provide the therapy model and middleware tools for psychologists to use in virtual therapeutic environments. We propose the Cyber Therapy Model, and Projective Agents, a tool used in the therapeutic environment. To evaluate the effectiveness of the tool, we created a prototype system, called the Virtual Group Counseling System, which is a therapeutic environment that allows the user to participate in group counseling through the eyes of their Projective Agent. Projective Agents inherit the user's personality traits. During the virtual group counseling, the user's Projective Agent interacts and collaborates to recover and increase their psychological growth. The prototype system provides a simulation environment where psychologists can adjust the parameters and customize their own simulation environment. The model and tool is a first attempt toward simulating online personalities that may exist only online, and provide data for observation.
Distributed virtual environment for emergency medical training
NASA Astrophysics Data System (ADS)
Stytz, Martin R.; Banks, Sheila B.; Garcia, Brian W.; Godsell-Stytz, Gayl M.
1997-07-01
In many professions where individuals must work in a team in a high stress environment to accomplish a time-critical task, individual and team performance can benefit from joint training using distributed virtual environments (DVEs). One professional field that lacks but needs a high-fidelity team training environment is the field of emergency medicine. Currently, emergency department (ED) medical personnel train by using words to create a metal picture of a situation for the physician and staff, who then cooperate to solve the problems portrayed by the word picture. The need in emergency medicine for realistic virtual team training is critical because ED staff typically encounter rarely occurring but life threatening situations only once in their careers and because ED teams currently have no realistic environment in which to practice their team skills. The resulting lack of experience and teamwork makes diagnosis and treatment more difficult. Virtual environment based training has the potential to redress these shortfalls. The objective of our research is to develop a state-of-the-art virtual environment for emergency medicine team training. The virtual emergency room (VER) allows ED physicians and medical staff to realistically prepare for emergency medical situations by performing triage, diagnosis, and treatment on virtual patients within an environment that provides them with the tools they require and the team environment they need to realistically perform these three tasks. There are several issues that must be addressed before this vision is realized. The key issues deal with distribution of computations; the doctor and staff interface to the virtual patient and ED equipment; the accurate simulation of individual patient organs' response to injury, medication, and treatment; and an accurate modeling of the symptoms and appearance of the patient while maintaining a real-time interaction capability. Our ongoing work addresses all of these issues. In this paper we report on our prototype VER system and its distributed system architecture for an emergency department distributed virtual environment for emergency medical staff training. The virtual environment enables emergency department physicians and staff to develop their diagnostic and treatment skills using the virtual tools they need to perform diagnostic and treatment tasks. Virtual human imagery, and real-time virtual human response are used to create the virtual patient and present a scenario. Patient vital signs are available to the emergency department team as they manage the virtual case. The work reported here consists of the system architectures we developed for the distributed components of the virtual emergency room. The architectures we describe consist of the network level architecture as well as the software architecture for each actor within the virtual emergency room. We describe the role of distributed interactive simulation and other enabling technologies within the virtual emergency room project.
Ecological validity of virtual environments to assess human navigation ability
van der Ham, Ineke J. M.; Faber, Annemarie M. E.; Venselaar, Matthijs; van Kreveld, Marc J.; Löffler, Maarten
2015-01-01
Route memory is frequently assessed in virtual environments. These environments can be presented in a fully controlled manner and are easy to use. Yet they lack the physical involvement that participants have when navigating real environments. For some aspects of route memory this may result in reduced performance in virtual environments. We assessed route memory performance in four different environments: real, virtual, virtual with directional information (compass), and hybrid. In the hybrid environment, participants walked the route outside on an open field, while all route information (i.e., path, landmarks) was shown simultaneously on a handheld tablet computer. Results indicate that performance in the real life environment was better than in the virtual conditions for tasks relying on survey knowledge, like pointing to start and end point, and map drawing. Performance in the hybrid condition however, hardly differed from real life performance. Performance in the virtual environment did not benefit from directional information. Given these findings, the hybrid condition may offer the best of both worlds: the performance level is comparable to that of real life for route memory, yet it offers full control of visual input during route learning. PMID:26074831
NASA Astrophysics Data System (ADS)
Ukpai, S. N.; Okogbue, C. O.
2017-11-01
Until this study, the location and depth of the saline units in Uburu-Okposi salt lake areas and environs have been unknown. This study aimed at delineating the saline lithofacies and dispersal configurations to water bodies, using electrical geophysical methods such as constant separation traversing (CST) and vertical electrical sounding (VES). Results showed weathered zones that represent aquifers mostly at the fourth geoelectric layer: between upper layered aquitards and underlying aquitards at depths 30-140 m. Lateral distribution of resistivity variance was defined by the CST, whereas the VES tool, targeted at low-resistivity zones, detected isolated saline units with less than 10 ohm-m at depths generally >78 m. The saline lithofacies were suspected to link freshwater zones via shear zones, which steer saline water towards the salt lakes and influence the vulnerability of groundwater to salinization. The level of salinization was verified by water sampling and analysis, and results showed general alkaline water type with a mean pH of 7.66. Water pollution was indicated: mean total dissolved solids (TDS) 550 mg/l, electrical conductivity (EC) 510 μS/cm, salinity 1.1‰, Cl- 200 mg/l, N03 -35.5 mg/l, Na+ 19.6 mg/l and Ca2+ 79.3 mg/l. The salinity is controlled by NaCl salt, as deduced from correlation analysis using the software package Statistical Product for Service Solutions (SPSS). Generally, concentrations of dissolved ions in the water of the area are enhanced via mechanisms such as evaporation, dissociation of salts, precipitation run off and leaching of dissolved rock minerals.
Virtual Virtuosos: A Case Study in Learning Music in Virtual Learning Environments in Spain
ERIC Educational Resources Information Center
Alberich-Artal, Enric; Sangra, Albert
2012-01-01
In recent years, the development of Information and Communication Technologies (ICT) has contributed to the generation of a number of interesting initiatives in the field of music education and training in virtual learning environments. However, music education initiatives employing virtual learning environments have replicated and perpetuated the…
Burbank works on the CIR in the U.S. Laboratory
2012-04-10
ISS030-E-234735 (10 April 2012) --- NASA astronaut Dan Burbank, Expedition 30 commander, works on the Combustion Integrated Rack (CIR) in the Destiny laboratory of the International Space Station. Burbank disconnected the Moderate Temperature Loop (MTL), Vacuum Exhaust System (VES) and station nitrogen lines of the Optics Bench, translated and rotated it out of the way and replaced a Fluids and Combustion Facility / Diagnostic Control Module (FCF DCM) on its back. Afterwards, Burbank returned the Optics Bench to its nominal position and reconnected the MTL, VES and station nitrogen lines.
VES263: an intermediate mass YSO candidate as a new eruptive variable
NASA Astrophysics Data System (ADS)
Giannini, T.; Antoniucci, S.; Lorenzetti, D.; Harutyunyan, A.; Licchelli, D.; Munari, U.
2018-05-01
In the framework of our EXor monitoring programme dubbed EXORCISM (EXOR OptiCal and Infrared Systematic Monitoring - Antoniucci et al. 2013 PPVI, Lorenzetti et al. 2007 ApJ 665, 1182; Lorenzetti et al. 2009 ApJ 693, 1056), we observed the object VES263 signalled by a recent GAIA alert (http://gsaweb.ast.cam.ac.uk/alerts/alert/Gaia18azl) as "an emission line star undergoing repeat outbursts" having detected an alerting magnitude of 11.66 wrt a historic magnitude of 12.16.
Transfer of motor learning from virtual to natural environments in individuals with cerebral palsy.
de Mello Monteiro, Carlos Bandeira; Massetti, Thais; da Silva, Talita Dias; van der Kamp, John; de Abreu, Luiz Carlos; Leone, Claudio; Savelsbergh, Geert J P
2014-10-01
With the growing accessibility of computer-assisted technology, rehabilitation programs for individuals with cerebral palsy (CP) increasingly use virtual reality environments to enhance motor practice. Thus, it is important to examine whether performance improvements in the virtual environment generalize to the natural environment. To examine this issue, we had 64 individuals, 32 of which were individuals with CP and 32 typically developing individuals, practice two coincidence-timing tasks. In the more tangible button-press task, the individuals were required to 'intercept' a falling virtual object at the moment it reached the interception point by pressing a key. In the more abstract, less tangible task, they were instructed to 'intercept' the virtual object by making a hand movement in a virtual environment. The results showed that individuals with CP timed less accurate than typically developing individuals, especially for the more abstract task in the virtual environment. The individuals with CP did-as did their typically developing peers-improve coincidence timing with practice on both tasks. Importantly, however, these improvements were specific to the practice environment; there was no transfer of learning. It is concluded that the implementation of virtual environments for motor rehabilitation in individuals with CP should not be taken for granted but needs to be considered carefully. Copyright © 2014 Elsevier Ltd. All rights reserved.
Can virtual reality be used to conduct mass prophylaxis clinic training? A pilot program.
Yellowlees, Peter; Cook, James N; Marks, Shayna L; Wolfe, Daniel; Mangin, Elanor
2008-03-01
To create and evaluate a pilot bioterrorism defense training environment using virtual reality technology. The present pilot project used Second Life, an internet-based virtual world system, to construct a virtual reality environment to mimic an actual setting that might be used as a Strategic National Stockpile (SNS) distribution site for northern California in the event of a bioterrorist attack. Scripted characters were integrated into the system as mock patients to analyze various clinic workflow scenarios. Users tested the virtual environment over two sessions. Thirteen users who toured the environment were asked to complete an evaluation survey. Respondents reported that the virtual reality system was relevant to their practice and had potential as a method of bioterrorism defense training. Computer simulations of bioterrorism defense training scenarios are feasible with existing personal computer technology. The use of internet-connected virtual environments holds promise for bioterrorism defense training. Recommendations are made for public health agencies regarding the implementation and benefits of using virtual reality for mass prophylaxis clinic training.
Development of a virtual speaking simulator using Image Based Rendering.
Lee, J M; Kim, H; Oh, M J; Ku, J H; Jang, D P; Kim, I Y; Kim, S I
2002-01-01
The fear of speaking is often cited as the world's most common social phobia. The rapid growth of computer technology has enabled the use of virtual reality (VR) for the treatment of the fear of public speaking. There are two techniques for building virtual environments for the treatment of this fear: a model-based and a movie-based method. Both methods have the weakness that they are unrealistic and not controllable individually. To understand these disadvantages, this paper presents a virtual environment produced with Image Based Rendering (IBR) and a chroma-key simultaneously. IBR enables the creation of realistic virtual environments where the images are stitched panoramically with the photos taken from a digital camera. And the use of chroma-keys puts virtual audience members under individual control in the environment. In addition, real time capture technique is used in constructing the virtual environments enabling spoken interaction between the subject and a therapist or another subject.
ERIC Educational Resources Information Center
O'Connor, Eileen A.
2015-01-01
Opening with the history, recent advances, and emerging ways to use avatar-based virtual reality, an instructor who has used virtual environments since 2007 shares how these environments bring more options to community building, teaching, and education. With the open-source movement, where the source code for virtual environments was made…
Perturbed Communication in a Virtual Environment to Train Medical Team Leaders.
Huguet, Lauriane; Lourdeaux, Domitile; Sabouret, Nicolas; Ferrer, Marie-Hélène
2016-01-01
The VICTEAMS project aims at designing a virtual environment for training medical team leaders to non-technical skills. The virtual environment is populated with autonomous virtual agents who are able to make mistakes (in action or communication) in order to train rescue team leaders and to make them adaptive with all kinds of situations or teams.
Aerospace applications of virtual environment technology.
Loftin, R B
1996-11-01
The uses of virtual environment technology in the space program are examined with emphasis on training for the Hubble Space Telescope Repair and Maintenance Mission in 1993. Project ScienceSpace at the Virtual Environment Technology Lab is discussed.
Social Interaction Development through Immersive Virtual Environments
ERIC Educational Resources Information Center
Beach, Jason; Wendt, Jeremy
2014-01-01
The purpose of this pilot study was to determine if participants could improve their social interaction skills by participating in a virtual immersive environment. The participants used a developing virtual reality head-mounted display to engage themselves in a fully-immersive environment. While in the environment, participants had an opportunity…
Gattinger, Pia; Lupinek, Christian; Kalogiros, Lampros; Silar, Mira; Zidarn, Mihaela; Korosec, Peter; Koessler, Christine; Novak, Natalija; Valenta, Rudolf; Mittermann, Irene
2018-01-01
Allergy to bee and wasp venom can lead to life-threatening systemic reactions. The identification of the culprit species is important for allergen-specific immunotherapy. To determine a panel of recombinant bee and wasp allergens which is suitable for the identification of bee or wasp as culprit allergen sources and to search for molecular surrogates of clinical severity of sting reactions. Sera from eighty-seven patients with a detailed documentation of their severity of sting reaction (Mueller grade) and who had been subjected to titrated skin testing with bee and wasp venom were analyzed for bee and wasp-specific IgE levels by ImmunoCAPTM. IgE-reactivity testing was performed using a comprehensive panel of recombinant bee and wasp venom allergens (rApi m 1, 2, 3, 4, 5 and 10; rVes v 1 and 5) by ISAC chip technology, ImmunoCAP and ELISA. IgG4 antibodies to rApi m 1 and rVes v 5 were determined by ELISA and IgE/IgG4 ratios were calculated. Results from skin testing, IgE serology and IgE/IgG4 ratios were compared with severity of sting reactions. The panel of rApi m 1, rApi m 10, rVes v 1 and rVes v 5 allowed identification of the culprit venom in all but two of the 87 patients with good agreement to skin testing. Severities of sting reactions were not associated with results obtained by skin testing, venom-specific IgE levels or molecular diagnosis. Severe sting reactions were observed in patients showing < 1 ISU and < 2kUA/L of IgE to Api m 1 and/or Ves v 5. We identified a minimal panel of recombinant bee and wasp allergens for molecular diagnosis which may permit identification of bee and/or wasp as culprit insect in venom-sensitized subjects. The severity of sting reactions was not associated with parameters obtained by molecular diagnosis.
Yoshida, Naruo; Hirata, Hirokuni; Watanabe, Mineaki; Sugiyama, Kumiya; Arima, Masafumi; Fukushima, Yasutsugu; Ishii, Yoshiki
2015-07-01
Ves v 5 and Pol d 5, which constitute antigen 5, are recognized as the major, most potent allergens of family Vespidae. Several studies have reported the diagnostic sensitivity of the novel recombinant (r)Ves v 5 and rPol d 5 allergens in routine clinical laboratory settings by analyzing a group of Vespula and Polistes venom-allergic patients. In this study, we analyzed the sensitivity to venom specific (s)IgE by spiking with rVes v 5 and rPol d 5 in Japanese patients suspected of Hymenoptera venom allergy. Subjects were 41 patients who had experienced systemic reactions to hornet and/or paper wasp stings. Levels of serum sIgE against hornet and paper wasp venom by spiking with rVes v 5 and rPold d 5, respectively, as improvement testing, compared with hornet and paper wasp venom, as conventional testing, were measured by ImmunoCAP. Of the 41 patients, 33 (80.5%) were positive (≥0.35 UA/ml) for hornet and/or paper wasp venom in conventional sIgE testing. sIgE levels correlated significantly (P < 0.01) between hornet (R = 0.92) or paper wasp venom (R = 0.78) in improvement testing and conventional testing. To determine specificity, 20 volunteers who had never experienced a Hymenoptera sting were all negative for sIgE against these venoms in both improvement and conventional testing. Improved sensitivity was seen in 8 patients negative for sIgE against both venoms in conventional testing, while improvement testing revealed sIgE against hornet or paper wasp venom in 5 (total 38 (92.7%)) patients. The measurement of sIgE following spiking of rVes v 5 and rPol d 5 by conventional testing in Japanese subjects with sIgE against hornet and paper wasp venom, respectively, improved the sensitivity for detecting Hymenoptera venom allergy. Improvement testing for measuring sIgE levels against hornet and paper wasp venom has potential for serologically elucidating Hymenoptera allergy in Japan. Copyright © 2015 Japanese Society of Allergology. Production and hosting by Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Leite, David Nakamura; Bortolozo, Cassiano Antonio; Porsani, Jorge Luís; Couto, Marco Antonio; Campaña, Julian David Realpe; dos Santos, Fernando Acácio Monteiro; Rangel, Rodrigo Corrêa; Hamada, Luiz Rodrigo; Sifontes, Rimary Valera; Serejo de Oliveira, Gabriela; Stangari, Marcelo César
2018-04-01
Although Brazil is well known by the large rivers and the Amazon Rain Forest most cities do not have access to sufficient quantities of surface water to supply the population. Because of this 61% of Brazilian population (IBGE, 2003) depends on groundwater resources. In order to help the conscious exploration of this resource in Urupês city (São Paulo State) which is characterized by problems of lack of water, this research applied the transient electromagnetic method (TDEM) and Vertical Electrical Sounding (VES) for the geoelectrical characterization of the interest region. So, the objective of this work was increase the hydrogeological basis for groundwater exploitation of Bauru sedimentary aquifer and Serra Geral fractured aquifer (Paraná Basin). A total of 23 TDEM and 15 VES soundings were conducted during the years of 2009, 2011 and 2012. In addition, 10 pairs of VES/TDEM soundings were acquired with coincident centers to be able to perform the joint inversion. The joint inversion technique is a promising tool, which enables to get the best of both methods, where the VES add the shallow information and TDEM the deeper one. In this work, the individual and joint inversions were performed using the "Curupira" software. After data process and inversion, the results were interpreted based on geological well information provided by the Department of Water and Electrical Power (DAEE) and the Brazilian Geological Survey (CPRM) which enabled to estimate favorable places to exploitation of water in Bauru and Serra Geral aquifers. For the Bauru aquifer, the results suggest areas where thickness exceeds 100 m. In these areas, the resistivity calculated was about 20 Ω·m. Therefore, the sediments have been interpreted as saturated sandy clay. In the basalt layer of Serra Geral Formation, the suggested locations present resistivity values <100 Ω·m at 200 m depth. The indicated places in sedimentary aquifer and the locations in the fractured aquifer will may show alternative sources for groundwater exploitation and water supply for Urupês city.
Virtual environments simulation in research reactor
NASA Astrophysics Data System (ADS)
Muhamad, Shalina Bt. Sheik; Bahrin, Muhammad Hannan Bin
2017-01-01
Virtual reality based simulations are interactive and engaging. It has the useful potential in improving safety training. Virtual reality technology can be used to train workers who are unfamiliar with the physical layout of an area. In this study, a simulation program based on the virtual environment at research reactor was developed. The platform used for virtual simulation is 3DVia software for which it's rendering capabilities, physics for movement and collision and interactive navigation features have been taken advantage of. A real research reactor was virtually modelled and simulated with the model of avatars adopted to simulate walking. Collision detection algorithms were developed for various parts of the 3D building and avatars to restrain the avatars to certain regions of the virtual environment. A user can control the avatar to move around inside the virtual environment. Thus, this work can assist in the training of personnel, as in evaluating the radiological safety of the research reactor facility.
Evaluation of the cognitive effects of travel technique in complex real and virtual environments.
Suma, Evan A; Finkelstein, Samantha L; Reid, Myra; V Babu, Sabarish; Ulinski, Amy C; Hodges, Larry F
2010-01-01
We report a series of experiments conducted to investigate the effects of travel technique on information gathering and cognition in complex virtual environments. In the first experiment, participants completed a non-branching multilevel 3D maze at their own pace using either real walking or one of two virtual travel techniques. In the second experiment, we constructed a real-world maze with branching pathways and modeled an identical virtual environment. Participants explored either the real or virtual maze for a predetermined amount of time using real walking or a virtual travel technique. Our results across experiments suggest that for complex environments requiring a large number of turns, virtual travel is an acceptable substitute for real walking if the goal of the application involves learning or reasoning based on information presented in the virtual world. However, for applications that require fast, efficient navigation or travel that closely resembles real-world behavior, real walking has advantages over common joystick-based virtual travel techniques.
Butterfly valve in a virtual environment
NASA Astrophysics Data System (ADS)
Talekar, Aniruddha; Patil, Saurabh; Thakre, Prashant; Rajkumar, E.
2017-11-01
Assembly of components is one of the processes involved in product design and development. The present paper deals with the assembly of a simple butterfly valve components in a virtual environment. The assembly has been carried out using virtual reality software by trial and error methods. The parts are modelled using parametric software (SolidWorks), meshed accordingly, and then called into virtual environment for assembly.
Ergonomic aspects of a virtual environment.
Ahasan, M R; Väyrynen, S
1999-01-01
A virtual environment is an interactive graphic system mediated through computer technology that allows a certain level of reality or a sense of presence to access virtual information. To create reality in a virtual environment, ergonomics issues are explored in this paper, aiming to develop the design of presentation formats with related information, that is possible to attain and to maintain user-friendly application.
Sarver, Nina Wong; Beidel, Deborah C; Spitalnick, Josh S
2014-01-01
Two significant challenges for the dissemination of social skills training programs are the need to assure generalizability and provide sufficient practice opportunities. In the case of social anxiety disorder, virtual environments may provide one strategy to address these issues. This study evaluated the utility of an interactive virtual school environment for the treatment of social anxiety disorder in preadolescent children. Eleven children with a primary diagnosis of social anxiety disorder between 8 to 12 years old participated in this initial feasibility trial. All children were treated with Social Effectiveness Therapy for Children, an empirically supported treatment for children with social anxiety disorder. However, the in vivo peer generalization sessions and standard parent-assisted homework assignments were substituted by practice in a virtual environment. Overall, the virtual environment programs were acceptable, feasible, and credible treatment components. Both children and clinicians were satisfied with using the virtual environment technology, and children believed it was a high-quality program overall. In addition, parents were satisfied with the virtual environment augmented treatment and indicated that they would recommend the program to family and friends. Findings indicate that the virtual environments are viewed as acceptable and credible by potential recipients. Furthermore, they are easy to implement by even novice users and appear to be useful adjunctive elements for the treatment of childhood social anxiety disorder.
Human Rights and Private Ordering in Virtual Worlds
NASA Astrophysics Data System (ADS)
Oosterbaan, Olivier
This paper explores the application of human rights in (persistent) virtual world environments. The paper begins with describing a number of elements that most virtual environments share and that are relevant for the application of human rights in such a setting; and by describing in a general nature the application of human rights between private individuals. The paper then continues by discussing the application in virtual environments of two universally recognized human rights, namely freedom of expression, and freedom from discrimination. As these specific rights are discussed, a number of more general conclusions on the application of human rights in virtual environments are drawn. The first general conclusion being that, because virtual worlds are private environments, participants are subject to private ordering. The second general conclusion being that participants and non-participants alike have to accept at times that in-world expressions are to an extent private speech. The third general conclusion is that, where participants represent themselves in-world, other participants cannot assume that such in-world representation share the characteristics of the human player; and that where virtual environments contain game elements, participants and non-participants alike should not take everything that happens in the virtual environment at face value or literally, which does however not amount to having to accept a higher level of infringement on their rights for things that happen in such an environment.
Wong, Nina; Beidel, Deborah C.; Spitalnick, Josh
2013-01-01
Objective Two significant challenges for the dissemination of social skills training programs are the need to assure generalizability and provide sufficient practice opportunities. In the case of social anxiety disorder, virtual environments may provide one strategy to address these issues. This study evaluated the utility of an interactive virtual school environment for the treatment of social anxiety disorder in preadolescent children. Method Eleven children with a primary diagnosis of social anxiety disorder between 8 to 12 years old participated in this initial feasibility trial. All children were treated with Social Effectiveness Therapy for Children, an empirically supported treatment for children with social anxiety disorder. However, the in vivo peer generalization sessions and standard parent-assisted homework assignments were substituted by practice in a virtual environment. Results Overall, the virtual environment programs were acceptable, feasible, and credible treatment components. Both children and clinicians were satisfied with using the virtual environment technology, and children believed it was a high quality program overall. Additionally, parents were satisfied with the virtual environment augmented treatment and indicated that they would recommend the program to family and friends. Conclusion Virtual environments are viewed as acceptable and credible by potential recipients. Furthermore, they are easy to implement by even novice users and appear to be useful adjunctive elements for the treatment of childhood social anxiety disorder. PMID:24144182
Geoelectric Characterization of Thermal Water Aquifers Using 2.5D Inversion of VES Measurements
NASA Astrophysics Data System (ADS)
Gyulai, Á.; Szűcs, P.; Turai, E.; Baracza, M. K.; Fejes, Z.
2017-03-01
This paper presents a short theoretical summary of the series expansion-based 2.5D combined geoelectric weighted inversion (CGWI) method and highlights the advantageous way with which the number of unknowns can be decreased due to the simultaneous characteristic of this inversion. 2.5D CGWI is an approximate inversion method for the determination of 3D structures, which uses the joint 2D forward modeling of dip and strike direction data. In the inversion procedure, the Steiner's most frequent value method is applied to the automatic separation of dip and strike direction data and outliers. The workflow of inversion and its practical application are presented in the study. For conventional vertical electrical sounding (VES) measurements, this method can determine the parameters of complex structures more accurately than the single inversion method. Field data show that the 2.5D CGWI which was developed can determine the optimal location for drilling an exploratory thermal water prospecting well. The novelty of this research is that the measured VES data in dip and strike direction are jointly inverted by the 2.5D CGWI method.
Design and Validation of PEG-Derivatized Vitamin E Copolymer for Drug Delivery into Breast Cancer.
Li, Yanping; Liu, Qinhui; Li, Wenyao; Zhang, Ting; Li, Hanmei; Li, Rui; Chen, Lei; Pu, Shiyun; Kuang, Jiangying; Su, Zhiguang; Zhang, Zhirong; He, Jinhan
2016-08-17
This study examined the ability of amphiphilic poly(ethylene glycol) (PEG) derivatives to assemble into micelles for drug delivery. Linear PEG chains were modified on one end with hydrophobic vitamin E succinate (VES), and PEG and VES were mixed in different molar ratios to make amphiphiles, which were characterized in terms of critical micelle concentration (CMC), drug loading capacity (DLC), serum stability, tumor spheroid penetration and tumor targeting in vitro and in vivo. The amphiphile PEG5K-VES6 (PAMV6), which has a wheat-like structure, showed a CMC of 3.03 × 10(-6) M, good serum stability, and tumor accumulation. The model drug, pirarubicin (THP), could be efficiently loaded into PAMV6 micelles at a DLC of 24.81%. PAMV6/THP micelles were more effective than THP solution at inducing cell apoptosis and G2/M arrest in 4T1 cells. THP-loaded PAMV6 micelles also inhibited tumor growth much more than free THP in a syngeneic mouse model of breast cancer. PAMV6-based micellar systems show promise as nanocarriers for improved anticancer chemotherapy.
SAFT VES180 SA High Specific Energy Cell Qualification
NASA Astrophysics Data System (ADS)
Borthomieu, Y.; Semerie, J.-P.
2005-05-01
A « high specific energy Li-Ion cell» is under development in the frame of the Artes 8 (Alphabus) programme. The purpose of this cell is to reduce the battery weight for the Alphabus satellite by at least 50 kg. The objective is to increase the specific energy by more than 25 % compared to the existing 140 Wh cell. The specific energy target for the 180Wh is 170 Wh/kg.In addition to improving the energy density, this development aimed to introduce a design improvement of the cell, in order to sustain higher mechanical environments than the state of the art cells.
NASA Astrophysics Data System (ADS)
Ge, Yuanzheng; Chen, Bin; liu, Liang; Qiu, Xiaogang; Song, Hongbin; Wang, Yong
2018-02-01
Individual-based computational environment provides an effective solution to study complex social events by reconstructing scenarios. Challenges remain in reconstructing the virtual scenarios and reproducing the complex evolution. In this paper, we propose a framework to reconstruct a synthetic computational environment, reproduce the epidemic outbreak, and evaluate management interventions in a virtual university. The reconstructed computational environment includes 4 fundamental components: the synthetic population, behavior algorithms, multiple social networks, and geographic campus environment. In the virtual university, influenza H1N1 transmission experiments are conducted, and gradually enhanced interventions are evaluated and compared quantitatively. The experiment results indicate that the reconstructed virtual environment provides a solution to reproduce complex emergencies and evaluate policies to be executed in the real world.
2009-03-20
involved the development of an environment within the Multiverse virtual world, oriented toward allowing individuals to acquire and reinforce skills via...PetBrain software G2: Creation of a scavenger hunt scenario in the Multiverse virtual world, in which humans and AIs can collaboratively play scavenger...carried out by Novamente LLC for AOARD during June 2008 ? February 2009. It involved the development of an environment within the Multiverse virtual world
Validation of smoking-related virtual environments for cue exposure therapy.
García-Rodríguez, Olaya; Pericot-Valverde, Irene; Gutiérrez-Maldonado, José; Ferrer-García, Marta; Secades-Villa, Roberto
2012-06-01
Craving is considered one of the main factors responsible for relapse after smoking cessation. Cue exposure therapy (CET) consists of controlled and repeated exposure to drug-related stimuli in order to extinguish associated responses. The main objective of this study was to assess the validity of 7 virtual reality environments for producing craving in smokers that can be used within the CET paradigm. Forty-six smokers and 44 never-smokers were exposed to 7 complex virtual environments with smoking-related cues that reproduce typical situations in which people smoke, and to a neutral virtual environment without smoking cues. Self-reported subjective craving and psychophysiological measures were recorded during the exposure. All virtual environments with smoking-related cues were able to generate subjective craving in smokers, while no increase was observed for the neutral environment. The most sensitive psychophysiological variable to craving increases was heart rate. The findings provide evidence of the utility of virtual reality for simulating real situations capable of eliciting craving. We also discuss how CET for smoking cessation can be improved through these virtual tools. Copyright © 2012 Elsevier Ltd. All rights reserved.
Distracting people from sources of discomfort in a simulated aircraft environment.
Lewis, Laura; Patel, Harshada; Cobb, Sue; D'Cruz, Mirabelle; Bues, Matthias; Stefani, Oliver; Grobler, Tredeaux
2016-07-19
Comfort is an important factor in the acceptance of transport systems. In 2010 and 2011, the European Commission (EC) put forward its vision for air travel in the year 2050 which envisaged the use of in-flight virtual reality. This paper addressed the EC vision by investigating the effect of virtual environments on comfort. Research has shown that virtual environments can provide entertaining experiences and can be effective distracters from painful experiences. To determine the extent to which a virtual environment could distract people from sources of discomfort. Experiments which involved inducing discomfort commonly experienced in-flight (e.g. limited space, noise) in order to determine the extent to which viewing a virtual environment could distract people from discomfort. Virtual environments can fully or partially distract people from sources of discomfort, becoming more effective when they are interesting. They are also more effective at distracting people from discomfort caused by restricted space than noise disturbances. Virtual environments have the potential to enhance passenger comfort by providing positive distractions from sources of discomfort. Further research is required to understand more fully the reasons why the effect was stronger for one source of discomfort than the other.
Paleotopographic control of landslides in lacustrine deposits (Trièves plateau, French western Alps)
NASA Astrophysics Data System (ADS)
Bièvre, Grégory; Kniess, Ulrich; Jongmans, Denis; Pathier, Erwan; Schwartz, Stéphane; van Westen, Cees J.; Villemin, Thierry; Zumbo, Vilma
2011-01-01
Paleotopography in Quaternary sedimentary environments can be an important factor that controls landslide movement. This study investigates the relation between paleotopography and landslide activity in two adjacent landslides in glaciolacustrine sediments located in the Trièves area (French western Alps). Although both are in slopes underlain by the same lacustrine deposits, the Avignonet and Harmalière landslides exhibit major differences in morphology and displacement rates. Through a combination of geological mapping, airborne light detection and ranging (LiDAR) data, aerial photographs, global positioning system (GPS), and seismic noise measurements, a three-dimensional impression was made of both landslides. The analysis reveals that the difference in kinematics between the two mass movements can be traced back to at least 50 years ago. The results show that the Harmalière slide, which failed catastrophically in 1981, is still much more active than the Avignonet landslide. The fear was that the Avignonet landslide might develop in a similar catastrophic manner, threatening a number of houses constructed on the landslide. A geophysical survey based on ambient noise measurements allowed us to map the base of the lacustrine clays, and the results indicate the presence of a N-S ridge of hard sediments (Jurassic bedrock and/or compact alluvial layers) on the eastern side of the Avignonet landslide. This ridge disappears when approaching the Harmalière landslide and makes a place to what can be interpreted as a NW-SE oriented paleovalley of the river Drac. We proposed that the ridge acts as a buttress that could mechanically prevent the Avignonet landslide from evolving as fast as the Harmalière. Furthermore, the NW-SE paleovalley located under the Harmalière landslide corresponds to the motion direction of the slide. Therefore, the different behaviour of the two landslides is partly controlled by the paleotopographic setting of Lake Trièves during the last Glacial Maximum extension. These results suggest a major influence of the bedrock paleotopography on the kinematics of the landslides.
Virtual environment architecture for rapid application development
NASA Technical Reports Server (NTRS)
Grinstein, Georges G.; Southard, David A.; Lee, J. P.
1993-01-01
We describe the MITRE Virtual Environment Architecture (VEA), a product of nearly two years of investigations and prototypes of virtual environment technology. This paper discusses the requirements for rapid prototyping, and an architecture we are developing to support virtual environment construction. VEA supports rapid application development by providing a variety of pre-built modules that can be reconfigured for each application session. The modules supply interfaces for several types of interactive I/O devices, in addition to large-screen or head-mounted displays.
Clandestine Message Passing in Virtual Environments
2008-09-01
accessed April 4, 2008). Weir, Laila. “Boring Game? Outsorce It.” (August 24, 2004). http://www.wired.com/ entertainment / music /news/2004/08/ 64638...Multiplayer Online MOVES - Modeling Virtual Environments and Simulation MTV – Music Television NPS - Naval Postgraduate School PAN – Personal Area...Network PSP - PlayStation Portable RPG – Role-playing Game SL - Second Life SVN - Subversion VE – Virtual Environments vMTV – Virtual Music
Pacheco, Thaiana Barbosa Ferreira; Oliveira Rego, Isabelle Ananda; Campos, Tania Fernandes; Cavalcanti, Fabrícia Azevedo da Costa
2017-01-01
Virtual Reality (VR) has been contributing to Neurological Rehabilitation because of its interactive and multisensory nature, providing the potential of brain reorganization. Given the use of mobile EEG devices, there is the possibility of investigating how the virtual therapeutic environment can influence brain activity. To compare theta, alpha, beta and gamma power in healthy young adults during a lower limb motor task in a virtual and real environment. Ten healthy adults were submitted to an EEG assessment while performing a one-minute task consisted of going up and down a step in a virtual environment - Nintendo Wii virtual game "Basic step" - and in a real environment. Real environment caused an increase in theta and alpha power, with small to large size effects mainly in the frontal region. VR caused a greater increase in beta and gamma power, however, with small or negligible effects on a variety of regions regarding beta frequency, and medium to very large effects on the frontal and the occipital regions considering gamma frequency. Theta, alpha, beta and gamma activity during the execution of a motor task differs according to the environment that the individual is exposed - real or virtual - and may have varying size effects if brain area activation and frequency spectrum in each environment are taken into consideration.
Virtual World Currency Value Fluctuation Prediction System Based on User Sentiment Analysis.
Kim, Young Bin; Lee, Sang Hyeok; Kang, Shin Jin; Choi, Myung Jin; Lee, Jung; Kim, Chang Hun
2015-01-01
In this paper, we present a method for predicting the value of virtual currencies used in virtual gaming environments that support multiple users, such as massively multiplayer online role-playing games (MMORPGs). Predicting virtual currency values in a virtual gaming environment has rarely been explored; it is difficult to apply real-world methods for predicting fluctuating currency values or shares to the virtual gaming world on account of differences in domains between the two worlds. To address this issue, we herein predict virtual currency value fluctuations by collecting user opinion data from a virtual community and analyzing user sentiments or emotions from the opinion data. The proposed method is straightforward and applicable to predicting virtual currencies as well as to gaming environments, including MMORPGs. We test the proposed method using large-scale MMORPGs and demonstrate that virtual currencies can be effectively and efficiently predicted with it.
Virtual World Currency Value Fluctuation Prediction System Based on User Sentiment Analysis
Kim, Young Bin; Lee, Sang Hyeok; Kang, Shin Jin; Choi, Myung Jin; Lee, Jung; Kim, Chang Hun
2015-01-01
In this paper, we present a method for predicting the value of virtual currencies used in virtual gaming environments that support multiple users, such as massively multiplayer online role-playing games (MMORPGs). Predicting virtual currency values in a virtual gaming environment has rarely been explored; it is difficult to apply real-world methods for predicting fluctuating currency values or shares to the virtual gaming world on account of differences in domains between the two worlds. To address this issue, we herein predict virtual currency value fluctuations by collecting user opinion data from a virtual community and analyzing user sentiments or emotions from the opinion data. The proposed method is straightforward and applicable to predicting virtual currencies as well as to gaming environments, including MMORPGs. We test the proposed method using large-scale MMORPGs and demonstrate that virtual currencies can be effectively and efficiently predicted with it. PMID:26241496
A computer vision system for the recognition of trees in aerial photographs
NASA Technical Reports Server (NTRS)
Pinz, Axel J.
1991-01-01
Increasing problems of forest damage in Central Europe set the demand for an appropriate forest damage assessment tool. The Vision Expert System (VES) is presented which is capable of finding trees in color infrared aerial photographs. Concept and architecture of VES are discussed briefly. The system is applied to a multisource test data set. The processing of this multisource data set leads to a multiple interpretation result for one scene. An integration of these results will provide a better scene description by the vision system. This is achieved by an implementation of Steven's correlation algorithm.
Research on Large Whales off California, Oregon, and Washington in 2003
2004-11-01
whale Fin whale Gray whale Humpback Killer whale Date VES Launch site Pers Activity Beg End Hours Nmi S# Tot IDs S# Tot IDs S# Tot IDs S# Tot IDs S...Humpback whale identifications are being compiled by DFO. Blue whale Fin whale Gray whale Humpback Killer whale Sperm whale Date VES Pers Beg End... Puget Sound 79 0 0 0 2 0 0 0 0 0 2 0 0 1 0 0 0 0 0 0 5 All 20 91 150 213 111 218 282 398 257 260 365 366 290 435 388 269 308 346 398 1,565
The effect of viewing a virtual environment through a head-mounted display on balance.
Robert, Maxime T; Ballaz, Laurent; Lemay, Martin
2016-07-01
In the next few years, several head-mounted displays (HMD) will be publicly released making virtual reality more accessible. HMD are expected to be widely popular at home for gaming but also in clinical settings, notably for training and rehabilitation. HMD can be used in both seated and standing positions; however, presently, the impact of HMD on balance remains largely unknown. It is therefore crucial to examine the impact of viewing a virtual environment through a HMD on standing balance. To compare static and dynamic balance in a virtual environment perceived through a HMD and the physical environment. The visual representation of the virtual environment was based on filmed image of the physical environment and was therefore highly similar. This is an observational study in healthy adults. No significant difference was observed between the two environments for static balance. However, dynamic balance was more perturbed in the virtual environment when compared to that of the physical environment. HMD should be used with caution because of its detrimental impact on dynamic balance. Sensorimotor conflict possibly explains the impact of HMD on balance. Copyright © 2016 Elsevier B.V. All rights reserved.
Vision-based navigation in a dynamic environment for virtual human
NASA Astrophysics Data System (ADS)
Liu, Yan; Sun, Ji-Zhou; Zhang, Jia-Wan; Li, Ming-Chu
2004-06-01
Intelligent virtual human is widely required in computer games, ergonomics software, virtual environment and so on. We present a vision-based behavior modeling method to realize smart navigation in a dynamic environment. This behavior model can be divided into three modules: vision, global planning and local planning. Vision is the only channel for smart virtual actor to get information from the outside world. Then, the global and local planning module use A* and D* algorithm to find a way for virtual human in a dynamic environment. Finally, the experiments on our test platform (Smart Human System) verify the feasibility of this behavior model.
Establishing a virtual learning environment: a nursing experience.
Wood, Anya; McPhee, Carolyn
2011-11-01
The use of virtual worlds has exploded in popularity, but getting started may not be easy. In this article, the authors, members of the corporate nursing education team at University Health Network, outline their experience with incorporating virtual technology into their learning environment. Over a period of several months, a virtual hospital, including two nursing units, was created in Second Life®, allowing more than 500 nurses to role-play in a safe environment without the fear of making a mistake. This experience has provided valuable insight into the best ways to develop and learn in a virtual environment. The authors discuss the challenges of installing and building the Second Life® platform and provide guidelines for preparing users and suggestions for crafting educational activities. This article provides a starting point for organizations planning to incorporate virtual worlds into their learning environment. Copyright 2011, SLACK Incorporated.
Height effects in real and virtual environments.
Simeonov, Peter I; Hsiao, Hongwei; Dotson, Brian W; Ammons, Douglas E
2005-01-01
The study compared human perceptions of height, danger, and anxiety, as well as skin conductance and heart rate responses and postural instability effects, in real and virtual height environments. The 24 participants (12 men, 12 women), whose average age was 23.6 years, performed "lean-over-the-railing" and standing tasks on real and comparable virtual balconies, using a surround-screen virtual reality (SSVR) system. The results indicate that the virtual display of elevation provided realistic perceptual experience and induced some physiological responses and postural instability effects comparable to those found in a real environment. It appears that a simulation of elevated work environment in a SSVR system, although with reduced visual fidelity, is a valid tool for safety research. Potential applications of this study include the design of virtual environments that will help in safe evaluation of human performance at elevation, identification of risk factors leading to fall incidents, and assessment of new fall prevention strategies.
Jones, Jake S.
1999-01-01
An apparatus and method of issuing commands to a computer by a user interfacing with a virtual reality environment. To issue a command, the user directs gaze at a virtual button within the virtual reality environment, causing a perceptible change in the virtual button, which then sends a command corresponding to the virtual button to the computer, optionally after a confirming action is performed by the user, such as depressing a thumb switch.
Perception of Graphical Virtual Environments by Blind Users via Sensory Substitution
Maidenbaum, Shachar; Buchs, Galit; Abboud, Sami; Lavi-Rotbain, Ori; Amedi, Amir
2016-01-01
Graphical virtual environments are currently far from accessible to blind users as their content is mostly visual. This is especially unfortunate as these environments hold great potential for this population for purposes such as safe orientation, education, and entertainment. Previous tools have increased accessibility but there is still a long way to go. Visual-to-audio Sensory-Substitution-Devices (SSDs) can increase accessibility generically by sonifying on-screen content regardless of the specific environment and offer increased accessibility without the use of expensive dedicated peripherals like electrode/vibrator arrays. Using SSDs virtually utilizes similar skills as when using them in the real world, enabling both training on the device and training on environments virtually before real-world visits. This could enable more complex, standardized and autonomous SSD training and new insights into multisensory interaction and the visually-deprived brain. However, whether congenitally blind users, who have never experienced virtual environments, will be able to use this information for successful perception and interaction within them is currently unclear.We tested this using the EyeMusic SSD, which conveys whole-scene visual information, to perform virtual tasks otherwise impossible without vision. Congenitally blind users had to navigate virtual environments and find doors, differentiate between them based on their features (Experiment1:task1) and surroundings (Experiment1:task2) and walk through them; these tasks were accomplished with a 95% and 97% success rate, respectively. We further explored the reactions of congenitally blind users during their first interaction with a more complex virtual environment than in the previous tasks–walking down a virtual street, recognizing different features of houses and trees, navigating to cross-walks, etc. Users reacted enthusiastically and reported feeling immersed within the environment. They highlighted the potential usefulness of such environments for understanding what visual scenes are supposed to look like and their potential for complex training and suggested many future environments they wished to experience. PMID:26882473
Perception of Graphical Virtual Environments by Blind Users via Sensory Substitution.
Maidenbaum, Shachar; Buchs, Galit; Abboud, Sami; Lavi-Rotbain, Ori; Amedi, Amir
2016-01-01
Graphical virtual environments are currently far from accessible to blind users as their content is mostly visual. This is especially unfortunate as these environments hold great potential for this population for purposes such as safe orientation, education, and entertainment. Previous tools have increased accessibility but there is still a long way to go. Visual-to-audio Sensory-Substitution-Devices (SSDs) can increase accessibility generically by sonifying on-screen content regardless of the specific environment and offer increased accessibility without the use of expensive dedicated peripherals like electrode/vibrator arrays. Using SSDs virtually utilizes similar skills as when using them in the real world, enabling both training on the device and training on environments virtually before real-world visits. This could enable more complex, standardized and autonomous SSD training and new insights into multisensory interaction and the visually-deprived brain. However, whether congenitally blind users, who have never experienced virtual environments, will be able to use this information for successful perception and interaction within them is currently unclear.We tested this using the EyeMusic SSD, which conveys whole-scene visual information, to perform virtual tasks otherwise impossible without vision. Congenitally blind users had to navigate virtual environments and find doors, differentiate between them based on their features (Experiment1:task1) and surroundings (Experiment1:task2) and walk through them; these tasks were accomplished with a 95% and 97% success rate, respectively. We further explored the reactions of congenitally blind users during their first interaction with a more complex virtual environment than in the previous tasks-walking down a virtual street, recognizing different features of houses and trees, navigating to cross-walks, etc. Users reacted enthusiastically and reported feeling immersed within the environment. They highlighted the potential usefulness of such environments for understanding what visual scenes are supposed to look like and their potential for complex training and suggested many future environments they wished to experience.
Ganier, Franck; Hoareau, Charlotte; Tisseau, Jacques
2014-01-01
Virtual reality opens new opportunities for operator training in complex tasks. It lowers costs and has fewer constraints than traditional training. The ultimate goal of virtual training is to transfer knowledge gained in a virtual environment to an actual real-world setting. This study tested whether a maintenance procedure could be learnt equally well by virtual-environment and conventional training. Forty-two adults were divided into three equally sized groups: virtual training (GVT® [generic virtual training]), conventional training (using a real tank suspension and preparation station) and control (no training). Participants then performed the procedure individually in the real environment. Both training types (conventional and virtual) produced similar levels of performance when the procedure was carried out in real conditions. Performance level for the two trained groups was better in terms of success and time taken to complete the task, time spent consulting job instructions and number of times the instructor provided guidance.
Focus, locus, and sensus: the three dimensions of virtual experience.
Waterworth, E L; Waterworth, J A
2001-04-01
A model of virtual/physical experience is presented, which provides a three dimensional conceptual space for virtual and augmented reality (VR and AR) comprising the dimensions of focus, locus, and sensus. Focus is most closely related to what is generally termed presence in the VR literature. When in a virtual environment, presence is typically shared between the VR and the physical world. "Breaks in presence" are actually shifts of presence away from the VR and toward the external environment. But we can also have "breaks in presence" when attention moves toward absence--when an observer is not attending to stimuli present in the virtual environment, nor to stimuli present in the surrounding physical environment--when the observer is present in neither the virtual nor the physical world. We thus have two dimensions of presence: focus of attention (between presence and absence) and the locus of attention (the virtual vs. the physical world). A third dimension is the sensus of attention--the level of arousal determining whether the observer is highly conscious or relatively unconscious while interacting with the environment. After expanding on each of these three dimensions of experience in relation to VR, we present a couple of educational examples as illustrations, and also relate our model to a suggested spectrum of evaluation methods for virtual environments.
Virtual Environments in Scientific Visualization
NASA Technical Reports Server (NTRS)
Bryson, Steve; Lisinski, T. A. (Technical Monitor)
1994-01-01
Virtual environment technology is a new way of approaching the interface between computers and humans. Emphasizing display and user control that conforms to the user's natural ways of perceiving and thinking about space, virtual environment technologies enhance the ability to perceive and interact with computer generated graphic information. This enhancement potentially has a major effect on the field of scientific visualization. Current examples of this technology include the Virtual Windtunnel being developed at NASA Ames Research Center. Other major institutions such as the National Center for Supercomputing Applications and SRI International are also exploring this technology. This talk will be describe several implementations of virtual environments for use in scientific visualization. Examples include the visualization of unsteady fluid flows (the virtual windtunnel), the visualization of geodesics in curved spacetime, surface manipulation, and examples developed at various laboratories.
Modulation of walking speed by changing optic flow in persons with stroke
Lamontagne, Anouk; Fung, Joyce; McFadyen, Bradford J; Faubert, Jocelyn
2007-01-01
Background Walking speed, which is often reduced after stroke, can be influenced by the perception of optic flow (OF) speed. The present study aims to: 1) compare the modulation of walking speed in response to OF speed changes between persons with stroke and healthy controls and 2) investigate whether virtual environments (VE) manipulating OF speed can be used to promote volitional changes in walking speed post stroke. Methods Twelve persons with stroke and 12 healthy individuals walked on a self-paced treadmill while viewing a virtual corridor in a helmet-mounted display. Two experiments were carried out on the same day. In experiment 1, the speed of an expanding OF was varied sinusoidally at 0.017 Hz (sine duration = 60 s), from 0 to 2 times the subject's comfortable walking speed, for a total duration of 5 minutes. In experiment 2, subjects were exposed to expanding OFs at discrete speeds that ranged from 0.25 to 2 times their comfortable speed. Each test trial was paired with a control trial performed at comfortable speed with matching OF. For each of the test trials, subjects were instructed to walk the distance within the same time as during the immediately preceding control trial. VEs were controlled by the CAREN-2 system (Motek). Instantaneous changes in gait speed (experiment 1) and the ratio of speed changes in the test trial over the control trial (experiment 2) were contrasted between the two groups of subjects. Results When OF speed was changing continuously (experiment 1), an out-of-phase modulation was observed in the gait speed of healthy subjects, such that slower OFs induced faster walking speeds, and vice versa. Persons with stroke displayed weaker (p < 0.05, T-test) correlation coefficients between gait speed and OF speed, due to less pronounced changes and an altered phasing of gait speed modulation. When OF speed was manipulated discretely (experiment 2), a negative linear relationship was generally observed between the test-control ratio of gait speed and OF speed in healthy and stroke individuals. The slope of this relationship was similar between the stroke and healthy groups (p > 0.05, T-test). Conclusion Stroke affects the modulation of gait speed in response to changes in the perception of movement through different OF speeds. Nevertheless, the preservation of even a modest modulation enabled the persons with stroke to increase walking speed when presented with slower OFs. Manipulation of OF speed using virtual reality technology could be implemented in a gait rehabilitation intervention to promote faster walking speeds after stroke. PMID:17594501
Digital Immersive Virtual Environments and Instructional Computing
ERIC Educational Resources Information Center
Blascovich, Jim; Beall, Andrew C.
2010-01-01
This article reviews theory and research relevant to the development of digital immersive virtual environment-based instructional computing systems. The review is organized within the context of a multidimensional model of social influence and interaction within virtual environments that models the interaction of four theoretical factors: theory…
Jones, J.S.
1999-01-12
An apparatus and method of issuing commands to a computer by a user interfacing with a virtual reality environment are disclosed. To issue a command, the user directs gaze at a virtual button within the virtual reality environment, causing a perceptible change in the virtual button, which then sends a command corresponding to the virtual button to the computer, optionally after a confirming action is performed by the user, such as depressing a thumb switch. 4 figs.
Ni, Jing; Pang, See-Too; Yeh, Shuyuan
2007-04-01
Epidemiological studies showed Vit E has protective effects against prostate cancer (PCa). Interestingly, different prostate cancer cells have different sensitivity to alpha-Vit E or VES treatment. The goal of this study is to determine whether cellular Vit E bioavailability and its transport proteins are important contributing factors. alpha-Vit E and its ester form, VES, were used to treat prostate cancer LNCaP, PC3, and DU145 cells, and their growth rates were determined by MTT assay. Cellular levels of Vit E were quantified using HPLC as the index of bioavailability. The expression levels of Vit E transport proteins were determined by real-time PCR. Among these PCa cells, only LNCaP cells were sensitive to 20 microM alpha-Vit E treatment, while both LNCaP and PC3 cells were sensitive to 20 microM VES treatment. Coordinately, cellular levels of alpha-Vit E and VES positively correlated to their inhibitory effects. Further study found expression levels of Vit E transport proteins, including tocopherol associated protein (TAP), scavenger receptor class B type I (SR-BI), alpha-tocopherol transfer protein (TTP), and ATP binding cassette transporter A1 (ABCA1), were different in various PCa cells, which may contribute to cellular Vit E bioavailability. This notion is further supported by the findings that overexpression or knockdown of TTP could coordinately alter cellular alpha-Vit E levels in PCa cells. Antiproliferative efficacy of alpha-Vit E is correlated with its cellular bioavailability in PCa cells. Modulating the expression of the efflux or influx transporters could sensitize the growth inhibition efficacy of Vit E in prostate cancer cells.
NASA Astrophysics Data System (ADS)
Younis, Abdellatif; Soliman, Mamdouh; Moussa, Salah; Massoud, Usama; ElNabi, Sami Abd; Attia, Magdy
2016-06-01
Continuous evaluation of groundwater aquifers in the basin of Kharga Oasis is very important. Groundwater in Kharga Oasis represents the major factor for the development plans of this area as it is the sole source for water supplies required for drinking and irrigation purposes. This study is concerned by analyzing the groundwater potentiality of the shallow aquifer at the northern part of Kharga basin by integrated application of Vertical Electrical Sounding (VES) and Time domain Electromagnetic (TEM) techniques. The VES data were measured at 28 points arranged along a north-south trending line by applying Schlumberger array with a maximum current-electrode spacing (AB) of 1000 m. The TEM data were measured at 167 points arranged along 11 east-west trending lines by using a single square loop with 50 m loop-side length. The VES and TEM data have been individually inverted, where the VES models were used as initial models for TEM data inversion. The final models were used for construction of 17 geoelectrical sections and 5 contour maps describing subsurface water-bearing layers at the investigated area. Correlation of the obtained models with geologic, hydrogeologic and borehole information indicates that the shallow aquifer comprises two zones (A-up) and (B-down) separated by a highly conductive shale layer. The upper zone (A) is composed of fine to medium sand with thin clay intercalations. It exhibits low to moderate resistivities. This zone was detected at depth values ranging from 10 to 70 m below ground surface (bgs) and shows a thickness of 25-90 m. The lower zone (B) exhibits moderate to high resistivity values with expected good water quality. The upper surface of zone B was detected at 60-165 m depth.
Owusu, Cynthia; Koroukian, Siran M.; Schluchter, Mark; Bakaki, Paul; Berger, Nathan A.
2011-01-01
Background The Vulnerable Elders Survey (VES-13) has been validated for screening older cancer patients for a Comprehensive Geriatric Assessment (CGA). To identify a widely acceptable approach that encourages oncologists to screen older cancer patients for a CGA, we examined the Eastern Cooperative Oncology Group Performance Status (ECOG-PS) and Karnofsky Index of Performance Status (KPS) scales’ ability to identify abnormalities on a CGA and compared the performance of the two instruments with the VES-13. Methods We enrolled 117 participants, ≥65 years with stage I–IV cancer into this cross-sectional study. Our primary outcome variable was ≥two abnormalities on the CGA, (Yes or No). We employed receiver operating characteristic curve analysis to compare the discriminatory abilities of the three instruments to identify ≥two abnormalities on the CGA. Results Of the 117 participants, 43% had ≥two abnormalities on the CGA. The VES-13 was predictive of ≥two abnormalities on the CGA, area under the curve (AUC)=0.85 [(95% CI: 0.78–0.92); sensitivity=88%, specificity=69%, at cut-off ≥3]. The ECOG-PS and KPS showed similar discriminatory powers, AUC=0.88 [(95% CI: 0.83–0.94); sensitivity=94%, specificity=55%, at cut-off ≥1]; and AUC=0.90 [(95% CI: 0.84–0.96); sensitivity=78%, specificity=91%, at cut-off ≤80%], respectively. Conclusion The ECOG-PS and KPS were equivalent to the VES-13 in identifying older cancer patients with at least two abnormalities on the CGA. Given that oncologists are already conversant with the KPS and ECOG-PS, these two instruments offer medical oncologists a widely acceptable approach for screening older patients for a CGA. PMID:21927633
Virtual Learning Environment for Interactive Engagement with Advanced Quantum Mechanics
ERIC Educational Resources Information Center
Pedersen, Mads Kock; Skyum, Birk; Heck, Robert; Müller, Romain; Bason, Mark; Lieberoth, Andreas; Sherson, Jacob F.
2016-01-01
A virtual learning environment can engage university students in the learning process in ways that the traditional lectures and lab formats cannot. We present our virtual learning environment "StudentResearcher," which incorporates simulations, multiple-choice quizzes, video lectures, and gamification into a learning path for quantum…
ERIC Educational Resources Information Center
Hassani, Kaveh; Nahvi, Ali; Ahmadi, Ali
2016-01-01
In this paper, we present an intelligent architecture, called intelligent virtual environment for language learning, with embedded pedagogical agents for improving listening and speaking skills of non-native English language learners. The proposed architecture integrates virtual environments into the Intelligent Computer-Assisted Language…
Usability Evaluation of an Adaptive 3D Virtual Learning Environment
ERIC Educational Resources Information Center
Ewais, Ahmed; De Troyer, Olga
2013-01-01
Using 3D virtual environments for educational purposes is becoming attractive because of their rich presentation and interaction capabilities. Furthermore, dynamically adapting the 3D virtual environment to the personal preferences, prior knowledge, skills and competence, learning goals, and the personal or (social) context in which the learning…
Exploring Non-Traditional Learning Methods in Virtual and Real-World Environments
ERIC Educational Resources Information Center
Lukman, Rebeka; Krajnc, Majda
2012-01-01
This paper identifies the commonalities and differences within non-traditional learning methods regarding virtual and real-world environments. The non-traditional learning methods in real-world have been introduced within the following courses: Process Balances, Process Calculation, and Process Synthesis, and within the virtual environment through…
Learning Relative Motion Concepts in Immersive and Non-Immersive Virtual Environments
ERIC Educational Resources Information Center
Kozhevnikov, Michael; Gurlitt, Johannes; Kozhevnikov, Maria
2013-01-01
The focus of the current study is to understand which unique features of an immersive virtual reality environment have the potential to improve learning relative motion concepts. Thirty-seven undergraduate students learned relative motion concepts using computer simulation either in immersive virtual environment (IVE) or non-immersive desktop…
ERIC Educational Resources Information Center
Katlianik, Ivan
2013-01-01
Enabling distant individuals to assemble in one virtual environment, synchronous distance learning appeals to researchers and practitioners alike because of its unique educational opportunities. One of the vital components of successful synchronous distance learning is interactivity. In virtual environments, interactivity is limited by the…
Nature and origins of virtual environments - A bibliographical essay
NASA Technical Reports Server (NTRS)
Ellis, S. R.
1991-01-01
Virtual environments presented via head-mounted, computer-driven displays provide a new media for communication. They may be analyzed by considering: (1) what may be meant by an environment; (2) what is meant by the process of virtualization; and (3) some aspects of human performance that constrain environmental design. Their origins are traced from previous work in vehicle simulation and multimedia research. Pointers are provided to key technical references, in the dispersed, archival literature, that are relevant to the development and evaluation of virtual-environment interface systems.
Ontological implications of being in immersive virtual environments
NASA Astrophysics Data System (ADS)
Morie, Jacquelyn F.
2008-02-01
The idea of Virtual Reality once conjured up visions of new territories to explore, and expectations of awaiting worlds of wonder. VR has matured to become a practical tool for therapy, medicine and commercial interests, yet artists, in particular, continue to expand the possibilities for the medium. Artistic virtual environments created over the past two decades probe the phenomenological nature of these virtual environments. When we inhabit a fully immersive virtual environment, we have entered into a new form of Being. Not only does our body continue to exist in the real, physical world, we are also embodied within the virtual by means of technology that translates our bodied actions into interactions with the virtual environment. Very few states in human existence allow this bifurcation of our Being, where we can exist simultaneously in two spaces at once, with the possible exception of meta-physical states such as shamanistic trance and out-of-body experiences. This paper discusses the nature of this simultaneous Being, how we enter the virtual space, what forms of persona we can don there, what forms of spaces we can inhabit, and what type of wondrous experiences we can both hope for and expect.
NASA Astrophysics Data System (ADS)
McFadden, D.; Tavakkoli, A.; Regenbrecht, J.; Wilson, B.
2017-12-01
Virtual Reality (VR) and Augmented Reality (AR) applications have recently seen an impressive growth, thanks to the advent of commercial Head Mounted Displays (HMDs). This new visualization era has opened the possibility of presenting researchers from multiple disciplines with data visualization techniques not possible via traditional 2D screens. In a purely VR environment researchers are presented with the visual data in a virtual environment, whereas in a purely AR application, a piece of virtual object is projected into the real world with which researchers could interact. There are several limitations to the purely VR or AR application when taken within the context of remote planetary exploration. For example, in a purely VR environment, contents of the planet surface (e.g. rocks, terrain, or other features) should be created off-line from a multitude of images using image processing techniques to generate 3D mesh data that will populate the virtual surface of the planet. This process usually takes a tremendous amount of computational resources and cannot be delivered in real-time. As an alternative, video frames may be superimposed on the virtual environment to save processing time. However, such rendered video frames will lack 3D visual information -i.e. depth information. In this paper, we present a technique to utilize a remotely situated robot's stereoscopic cameras to provide a live visual feed from the real world into the virtual environment in which planetary scientists are immersed. Moreover, the proposed technique will blend the virtual environment with the real world in such a way as to preserve both the depth and visual information from the real world while allowing for the sensation of immersion when the entire sequence is viewed via an HMD such as Oculus Rift. The figure shows the virtual environment with an overlay of the real-world stereoscopic video being presented in real-time into the virtual environment. Notice the preservation of the object's shape, shadows, and depth information. The distortions shown in the image are due to the rendering of the stereoscopic data into a 2D image for the purposes of taking screenshots.
The virtual environment display system
NASA Technical Reports Server (NTRS)
Mcgreevy, Michael W.
1991-01-01
Virtual environment technology is a display and control technology that can surround a person in an interactive computer generated or computer mediated virtual environment. It has evolved at NASA-Ames since 1984 to serve NASA's missions and goals. The exciting potential of this technology, sometimes called Virtual Reality, Artificial Reality, or Cyberspace, has been recognized recently by the popular media, industry, academia, and government organizations. Much research and development will be necessary to bring it to fruition.
Measurement Tools for the Immersive Visualization Environment: Steps Toward the Virtual Laboratory.
Hagedorn, John G; Dunkers, Joy P; Satterfield, Steven G; Peskin, Adele P; Kelso, John T; Terrill, Judith E
2007-01-01
This paper describes a set of tools for performing measurements of objects in a virtual reality based immersive visualization environment. These tools enable the use of the immersive environment as an instrument for extracting quantitative information from data representations that hitherto had be used solely for qualitative examination. We provide, within the virtual environment, ways for the user to analyze and interact with the quantitative data generated. We describe results generated by these methods to obtain dimensional descriptors of tissue engineered medical products. We regard this toolbox as our first step in the implementation of a virtual measurement laboratory within an immersive visualization environment.
Modeling Environmental Impacts on Cognitive Performance for Artificially Intelligent Entities
2017-06-01
of the agent behavior model is presented in a military-relevant virtual game environment. We then outline a quantitative approach to test the agent...relevant virtual game environment. We then outline a quantitative approach to test the agent behavior model within the virtual environment. Results show...x Game View of Hot Environment Condition Displaying Total “f” Cost for Each Searched Waypoint Node
ERIC Educational Resources Information Center
Lim, Keol; Kim, Mi Hwa
2015-01-01
The use of virtual learning environments (VLEs) has become more common and educators recognized the potential of VLEs as educational environments. The learning community in VLEs can be a mixture of people from all over the world with different cultural backgrounds. However, despite many studies about the use of virtual environments for learning,…
Methods and systems relating to an augmented virtuality environment
Nielsen, Curtis W; Anderson, Matthew O; McKay, Mark D; Wadsworth, Derek C; Boyce, Jodie R; Hruska, Ryan C; Koudelka, John A; Whetten, Jonathan; Bruemmer, David J
2014-05-20
Systems and methods relating to an augmented virtuality system are disclosed. A method of operating an augmented virtuality system may comprise displaying imagery of a real-world environment in an operating picture. The method may further include displaying a plurality of virtual icons in the operating picture representing at least some assets of a plurality of assets positioned in the real-world environment. Additionally, the method may include displaying at least one virtual item in the operating picture representing data sensed by one or more of the assets of the plurality of assets and remotely controlling at least one asset of the plurality of assets by interacting with a virtual icon associated with the at least one asset.
Object Creation and Human Factors Evaluation for Virtual Environments
NASA Technical Reports Server (NTRS)
Lindsey, Patricia F.
1998-01-01
The main objective of this project is to provide test objects for simulated environments utilized by the recently established Army/NASA Virtual Innovations Lab (ANVIL) at Marshall Space Flight Center, Huntsville, Al. The objective of the ANVIL lab is to provide virtual reality (VR) models and environments and to provide visualization and manipulation methods for the purpose of training and testing. Visualization equipment used in the ANVIL lab includes head-mounted and boom-mounted immersive virtual reality display devices. Objects in the environment are manipulated using data glove, hand controller, or mouse. These simulated objects are solid or surfaced three dimensional models. They may be viewed or manipulated from any location within the environment and may be viewed on-screen or via immersive VR. The objects are created using various CAD modeling packages and are converted into the virtual environment using dVise. This enables the object or environment to be viewed from any angle or distance for training or testing purposes.
The Influence of Virtual Learning Environments in Students' Performance
ERIC Educational Resources Information Center
Alves, Paulo; Miranda, Luísa; Morais, Carlos
2017-01-01
This paper focuses mainly on the relation between the use of a virtual learning environment (VLE) and students' performance. Therefore, virtual learning environments are characterised and a study is presented emphasising the frequency of access to a VLE and its relation with the students' performance from a public higher education institution…
Full Immersive Virtual Environment Cave[TM] in Chemistry Education
ERIC Educational Resources Information Center
Limniou, M.; Roberts, D.; Papadopoulos, N.
2008-01-01
By comparing two-dimensional (2D) chemical animations designed for computer's desktop with three-dimensional (3D) chemical animations designed for the full immersive virtual reality environment CAVE[TM] we studied how virtual reality environments could raise student's interest and motivation for learning. By using the 3ds max[TM], we can visualize…
Temporal Issues in the Design of Virtual Learning Environments.
ERIC Educational Resources Information Center
Bergeron, Bryan; Obeid, Jihad
1995-01-01
Describes design methods used to influence user perception of time in virtual learning environments. Examines the use of temporal cues in medical education and clinical competence testing. Finds that user perceptions of time affects user acceptance, ease of use, and the level of realism of a virtual learning environment. Contains 51 references.…
The Doubtful Guest? A Virtual Research Environment for Education
ERIC Educational Resources Information Center
Laterza, Vito; Carmichael, Patrick; Procter, Richard
2007-01-01
In this paper the authors describe a novel "Virtual Research Environment" (VRE) based on the Sakai Virtual Collaboration Environment and designed to support education research. This VRE has been used for the past two years by projects of the UK Economic and Social Research Council's Teaching and Learning Research Programme, 10 of which…
Using Virtual Reality to Help Students with Social Interaction Skills
ERIC Educational Resources Information Center
Beach, Jason; Wendt, Jeremy
2015-01-01
The purpose of this study was to determine if participants could improve their social interaction skills by participating in a virtual immersive environment. The participants used a developing virtual reality head-mounted display to engage themselves in a fully-immersive environment. While in the environment, participants had an opportunity to…
ERIC Educational Resources Information Center
Passarelli, Brasilina
2008-01-01
Introduction: The ToLigado Project--Your School Interactive Newspaper is an interactive virtual learning environment conceived, developed, implemented and supported by researchers at the School of the Future Research Laboratory of the University of Sao Paulo, Brazil. Method: This virtual learning environment aims to motivate trans-disciplinary…
Using SOLO to Evaluate an Educational Virtual Environment in a Technology Education Setting
ERIC Educational Resources Information Center
Padiotis, Ioannis; Mikropoulos, Tassos A.
2010-01-01
The present research investigates the contribution of an interactive educational virtual environment on milk pasteurization to the learning outcomes of 40 students in a technical secondary school using SOLO taxonomy. After the interaction with the virtual environment the majority of the students moved to higher hierarchical levels of understanding…
Virtual Environments Supporting Learning and Communication in Special Needs Education
ERIC Educational Resources Information Center
Cobb, Sue V. G.
2007-01-01
Virtual reality (VR) describes a set of technologies that allow users to explore and experience 3-dimensional computer-generated "worlds" or "environments." These virtual environments can contain representations of real or imaginary objects on a small or large scale (from modeling of molecular structures to buildings, streets, and scenery of a…
ERIC Educational Resources Information Center
Akdemir, Ömür; Vural, Ömer F.; Çolakoglu, Özgür M.
2015-01-01
Individuals act different in virtual environment than real life. The primary purpose of this study is to investigate the prospective teachers' likelihood of performing unethical behaviors in the real and virtual environments. Prospective teachers are surveyed online and their perceptions have been collected for various scenarios. Findings revealed…
Virtual environments for scene of crime reconstruction and analysis
NASA Astrophysics Data System (ADS)
Howard, Toby L. J.; Murta, Alan D.; Gibson, Simon
2000-02-01
This paper describes research conducted in collaboration with Greater Manchester Police (UK), to evalute the utility of Virtual Environments for scene of crime analysis, forensic investigation, and law enforcement briefing and training. We present an illustrated case study of the construction of a high-fidelity virtual environment, intended to match a particular real-life crime scene as closely as possible. We describe and evaluate the combination of several approaches including: the use of the Manchester Scene Description Language for constructing complex geometrical models; the application of a radiosity rendering algorithm with several novel features based on human perceptual consideration; texture extraction from forensic photography; and experiments with interactive walkthroughs and large-screen stereoscopic display of the virtual environment implemented using the MAVERIK system. We also discuss the potential applications of Virtual Environment techniques in the Law Enforcement and Forensic communities.
Exploration for limestone deposit at Onigbedu, South-Western Nigeria
NASA Astrophysics Data System (ADS)
Oyedele, Kayode F.; Oladele, Sunday; Emakpor, Charles A.
2016-09-01
The Onigbedu limestone deposit was investigated using the aeromagnetic data, resistivity soundings and borings with the aim of characterizing the limestone deposit and estimating its reserves. The subsurface structural features and depth to basement were identified with the analysis of aeromagnetic data. Twenty nine boreholes were drilled for subsurface appraisal and correlation of the limestone deposit. Eighty nine Vertical Electrical Sounding (VES) were acquired using the Schlumberger array. The results showed NE-SW trending lineaments that segmented the limestone. Depth to basement varied from 144.2 m to 1090 m. The VES results showed four to six layers indicating the topsoil (7-315 Ωm), clay (2-25 Ωm), shale (6-31 Ωm), limestone (20-223 Ωm), sandstone (>200 Ωm) and sandy materials. The VES results correlated well with the lithological unit delineated from the borehole. The overburden thickness ranged from 3.3 m to 28 m, while the limestone thickness varies between 18.1 m and 48.3 m. The limestone reserve was estimated at 1.9 × 109 t. This study concluded that the study area had vast occurrence of the limestone deposits, which would be of economic importance, if exploited.
NASA Astrophysics Data System (ADS)
Singh, U. K.; Tiwari, R. K.; Singh, S. B.
2005-02-01
This paper deals with the application of artificial neural networks (ANN) technique for the study of a case history using 1-D inversion of vertical electrical resistivity sounding (VES) data from the Puga valley, Kashmir, India. The study area is important for its rich geothermal resources as well as from the tectonic point of view as it is located near the collision boundary of the Indo-Asian crustal plates. In order to understand the resistivity structure and layer thicknesses, we used here three-layer feedforward neural networks to model and predict measured VES data. Three algorithms, e.g. back-propagation (BP), adaptive back-propagation (ABP) and Levenberg-Marquardt algorithm (LMA) were applied to the synthetic as well as real VES field data and efficiency of supervised training network are compared. Analyses suggest that LMA is computationally faster and give results, which are comparatively more accurate and consistent than BP and ABP. The results obtained using the ANN inversions are remarkably correlated with the available borehole litho-logs. The feasibility study suggests that ANN methods offer an excellent complementary tool for the direct detection of layered resistivity structure.
Emerging CAE technologies and their role in Future Ambient Intelligence Environments
NASA Astrophysics Data System (ADS)
Noor, Ahmed K.
2011-03-01
Dramatic improvements are on the horizon in Computer Aided Engineering (CAE) and various simulation technologies. The improvements are due, in part, to the developments in a number of leading-edge technologies and their synergistic combinations/convergence. The technologies include ubiquitous, cloud, and petascale computing; ultra high-bandwidth networks, pervasive wireless communication; knowledge based engineering; networked immersive virtual environments and virtual worlds; novel human-computer interfaces; and powerful game engines and facilities. This paper describes the frontiers and emerging simulation technologies, and their role in the future virtual product creation and learning/training environments. The environments will be ambient intelligence environments, incorporating a synergistic combination of novel agent-supported visual simulations (with cognitive learning and understanding abilities); immersive 3D virtual world facilities; development chain management systems and facilities (incorporating a synergistic combination of intelligent engineering and management tools); nontraditional methods; intelligent, multimodal and human-like interfaces; and mobile wireless devices. The Virtual product creation environment will significantly enhance the productivity and will stimulate creativity and innovation in future global virtual collaborative enterprises. The facilities in the learning/training environment will provide timely, engaging, personalized/collaborative and tailored visual learning.
The Problem Patron and the Academic Library Web Site as Virtual Reference Desk.
ERIC Educational Resources Information Center
Taylor, Daniel; Porter, George S.
2002-01-01
Considers problem library patrons in a virtual environment based on experiences at California Institute of Technology's Web site and its use for virtual reference. Discusses the virtual reference desk concept; global visibility and access to the World Wide Web; problematic email; and advantages in the electronic environment. (LRW)
Brundage, Shelley B; Brinton, James M; Hancock, Adrienne B
2016-12-01
Virtual reality environments (VREs) allow for immersion in speaking environments that mimic real-life interactions while maintaining researcher control. VREs have been used successfully to engender arousal in other disorders. The purpose of this study was to investigate the utility of virtual reality environments to examine physiological reactivity and subjective ratings of distress in persons who stutter (PWS). Subjective and objective measures of arousal were collected from 10PWS during four-minute speeches to a virtual audience and to a virtual empty room. Stuttering frequency and physiological measures (skin conductance level and heart rate) did not differ across speaking conditions, but subjective ratings of distress were significantly higher in the virtual audience condition compared to the virtual empty room. VREs have utility in elevating subjective ratings of distress in PWS. VREs have the potential to be useful tools for practicing treatment targets in a safe, controlled, and systematic manner. Copyright © 2016 Elsevier Inc. All rights reserved.
A Proposed Framework for Collaborative Design in a Virtual Environment
NASA Astrophysics Data System (ADS)
Breland, Jason S.; Shiratuddin, Mohd Fairuz
This paper describes a proposed framework for a collaborative design in a virtual environment. The framework consists of components that support a true collaborative design in a real-time 3D virtual environment. In support of the proposed framework, a prototype application is being developed. The authors envision the framework will have, but not limited to the following features: (1) real-time manipulation of 3D objects across the network, (2) support for multi-designer activities and information access, (3) co-existence within same virtual space, etc. This paper also discusses a proposed testing to determine the possible benefits of a collaborative design in a virtual environment over other forms of collaboration, and results from a pilot test.
Information Virtulization in Virtual Environments
NASA Technical Reports Server (NTRS)
Bryson, Steve; Kwak, Dochan (Technical Monitor)
2001-01-01
Virtual Environments provide a natural setting for a wide range of information visualization applications, particularly wlieit the information to be visualized is defined on a three-dimensional domain (Bryson, 1996). This chapter provides an overview of the issues that arise when designing and implementing an information visualization application in a virtual environment. Many design issues that arise, such as, e.g., issues of display, user tracking are common to any application of virtual environments. In this chapter we focus on those issues that are special to information visualization applications, as issues of wider concern are addressed elsewhere in this book.
Kibria, Muhammad Golam; Ali, Sajjad; Jarwar, Muhammad Aslam; Kumar, Sunil; Chong, Ilyoung
2017-09-22
Due to a very large number of connected virtual objects in the surrounding environment, intelligent service features in the Internet of Things requires the reuse of existing virtual objects and composite virtual objects. If a new virtual object is created for each new service request, then the number of virtual object would increase exponentially. The Web of Objects applies the principle of service modularity in terms of virtual objects and composite virtual objects. Service modularity is a key concept in the Web Objects-Enabled Internet of Things (IoT) environment which allows for the reuse of existing virtual objects and composite virtual objects in heterogeneous ontologies. In the case of similar service requests occurring at the same, or different locations, the already-instantiated virtual objects and their composites that exist in the same, or different ontologies can be reused. In this case, similar types of virtual objects and composite virtual objects are searched and matched. Their reuse avoids duplication under similar circumstances, and reduces the time it takes to search and instantiate them from their repositories, where similar functionalities are provided by similar types of virtual objects and their composites. Controlling and maintaining a virtual object means controlling and maintaining a real-world object in the real world. Even though the functional costs of virtual objects are just a fraction of those for deploying and maintaining real-world objects, this article focuses on reusing virtual objects and composite virtual objects, as well as discusses similarity matching of virtual objects and composite virtual objects. This article proposes a logistic model that supports service modularity for the promotion of reusability in the Web Objects-enabled IoT environment. Necessary functional components and a flowchart of an algorithm for reusing composite virtual objects are discussed. Also, to realize the service modularity, a use case scenario is studied and implemented.
Chong, Ilyoung
2017-01-01
Due to a very large number of connected virtual objects in the surrounding environment, intelligent service features in the Internet of Things requires the reuse of existing virtual objects and composite virtual objects. If a new virtual object is created for each new service request, then the number of virtual object would increase exponentially. The Web of Objects applies the principle of service modularity in terms of virtual objects and composite virtual objects. Service modularity is a key concept in the Web Objects-Enabled Internet of Things (IoT) environment which allows for the reuse of existing virtual objects and composite virtual objects in heterogeneous ontologies. In the case of similar service requests occurring at the same, or different locations, the already-instantiated virtual objects and their composites that exist in the same, or different ontologies can be reused. In this case, similar types of virtual objects and composite virtual objects are searched and matched. Their reuse avoids duplication under similar circumstances, and reduces the time it takes to search and instantiate them from their repositories, where similar functionalities are provided by similar types of virtual objects and their composites. Controlling and maintaining a virtual object means controlling and maintaining a real-world object in the real world. Even though the functional costs of virtual objects are just a fraction of those for deploying and maintaining real-world objects, this article focuses on reusing virtual objects and composite virtual objects, as well as discusses similarity matching of virtual objects and composite virtual objects. This article proposes a logistic model that supports service modularity for the promotion of reusability in the Web Objects-enabled IoT environment. Necessary functional components and a flowchart of an algorithm for reusing composite virtual objects are discussed. Also, to realize the service modularity, a use case scenario is studied and implemented. PMID:28937590
Proof-of-Concept Part Task Trainer for Close Air Support Procedures
2016-06-01
TVDL Tactical Video Down Link VE Virtual Environment VR Virtual Reality WTI Weapons and Tactics Instructor xvii ACKNOWLEDGMENTS I would first...in training of USMC pilots for close air support operations? • What is the feasibility of developing a prototype virtual reality (VR) system that...Chapter IV provides a review of virtual reality (VR)/ virtual environment (VE) and part-task trainers currently used in military training
360° Film Brings Bombed Church to Life
NASA Astrophysics Data System (ADS)
Kwiatek, K.
2011-09-01
This paper explores how a computer-generated reconstruction of a church can be adapted to create a panoramic film that is presented in a panoramic viewer and also on a wrap-around projection system. It focuses on the fundamental principles of creating 360º films, not only in 3D modelling software, but also presents how to record 360º video using panoramic cameras inside the heritage site. These issues are explored in a case study of Charles Church in Plymouth, UK that was bombed in 1941 and has never been rebuilt. The generation of a 3D model of the bombed church started from the creation of five spherical panoramas and through the use of Autodesk ImageModeler software. The processed files were imported and merged together in Autodesk 3ds Max where a visualisation of the ruin was produced. A number of historical images were found and this collection enabled the process of a virtual reconstruction of the site. The aspect of merging two still or two video panoramas (one from 3D modelling software, the other one recorded on the site) from the same locations or with the same trajectories is also discussed. The prototype of 360º non-linear film tells a narrative of a wartime wedding that occurred in this church. The film was presented on two 360º screens where members of the audience could make decisions on whether to continue the ceremony or whether to run away when the bombing of the church starts. 3D modelling software made this possible to render a number of different alternati ves (360º images and 360º video). Immersive environments empower the visitor to imagine the building before it was destroyed.
NASA Astrophysics Data System (ADS)
Frend, Chauncey; Boyles, Michael
2015-03-01
This paper describes an environmental feedback device (EFD) control system aimed at simplifying the VR development cycle. Programmable Immersive Peripheral Environmental System (PIPES) affords VR developers a custom approach to programming and controlling EFD behaviors while relaxing the required knowledge and expertise of electronic systems. PIPES has been implemented for the Unity engine and features EFD control using the Arduino integrated development environment. PIPES was installed and tested on two VR systems, a large format CAVE system and an Oculus Rift HMD system. A photocell based end-to-end latency experiment was conducted to measure latency within the system. This work extends previously unpublished prototypes of a similar design. Development and experiments described in this paper are part of the VR community goal to understand and apply environment effects to VEs that ultimately add to users' perceived presence.
NASA Astrophysics Data System (ADS)
Prusten, Mark J.; McIntyre, Michelle; Landis, Marvin
2006-02-01
A 3D workflow pipeline is presented for High Dynamic Range (HDR) image capture of projected scenes or objects for presentation in CAVE virtual environments. The methods of HDR digital photography of environments vs. objects are reviewed. Samples of both types of virtual authoring being the actual CAVE environment and a sculpture are shown. A series of software tools are incorporated into a pipeline called CAVEPIPE, allowing for high-resolution objects and scenes to be composited together in natural illumination environments [1] and presented in our CAVE virtual reality environment. We also present a way to enhance the user interface for CAVE environments. The traditional methods of controlling the navigation through virtual environments include: glove, HUD's and 3D mouse devices. By integrating a wireless network that includes both WiFi (IEEE 802.11b/g) and Bluetooth (IEEE 802.15.1) protocols the non-graphical input control device can be eliminated. Therefore wireless devices can be added that would include: PDA's, Smart Phones, TabletPC's, Portable Gaming consoles, and PocketPC's.
Computer Vision Assisted Virtual Reality Calibration
NASA Technical Reports Server (NTRS)
Kim, W.
1999-01-01
A computer vision assisted semi-automatic virtual reality (VR) calibration technology has been developed that can accurately match a virtual environment of graphically simulated three-dimensional (3-D) models to the video images of the real task environment.
NASA Technical Reports Server (NTRS)
Benford, Steve; Bowers, John; Fahlen, Lennart E.; Greenhalgh, Chris; Snowdon, Dave
1994-01-01
This paper explores the issue of user embodiment within collaborative virtual environments. By user embodiment we mean the provision of users with appropriate body images so as to represent them to others and also to themselves. By collaborative virtual environments we mean multi-user virtual reality systems which support cooperative work (although we argue that the results of our exploration may also be applied to other kinds of collaborative systems). The main part of the paper identifies a list of embodiment design issues including: presence, location, identity, activity, availability, history of activity, viewpoint, action point, gesture, facial expression, voluntary versus involuntary expression, degree of presence, reflecting capabilities, manipulating the user's view of others, representation across multiple media, autonomous and distributed body parts, truthfulness and efficiency. Following this, we show how these issues are reflected in our own DIVE and MASSIVE prototype collaborative virtual environments.
Perfecting Scientists' Collaboration and Problem-Solving Skills in the Virtual Team Environment
NASA Astrophysics Data System (ADS)
Jabro, A.; Jabro, J.
2012-04-01
PPerfecting Scientists' Collaboration and Problem-Solving Skills in the Virtual Team Environment Numerous factors have contributed to the proliferation of conducting work in virtual teams at the domestic, national, and global levels: innovations in technology, critical developments in software, co-located research partners and diverse funding sources, dynamic economic and political environments, and a changing workforce. Today's scientists must be prepared to not only perform work in the virtual team environment, but to work effectively and efficiently despite physical and cultural barriers. Research supports that students who have been exposed to virtual team experiences are desirable in the professional and academic arenas. Research supports establishing and maintaining established protocols for communication behavior prior to task discussion provides for successful team outcomes. Research conducted on graduate and undergraduate virtual teams' behaviors led to the development of successful pedagogic practices and assessment strategies.
3D multiplayer virtual pets game using Google Card Board
NASA Astrophysics Data System (ADS)
Herumurti, Darlis; Riskahadi, Dimas; Kuswardayan, Imam
2017-08-01
Virtual Reality (VR) is a technology which allows user to interact with the virtual environment. This virtual environment is generated and simulated by computer. This technology can make user feel the sensation when they are in the virtual environment. The VR technology provides real virtual environment view for user and it is not viewed from screen. But it needs another additional device to show the view of virtual environment. This device is known as Head Mounted Device (HMD). Oculust Rift and Microsoft Hololens are the most famous HMD devices used in VR. And in 2014, Google Card Board was introduced at Google I/O developers conference. Google Card Board is VR platform which allows user to enjoy the VR with simple and cheap way. In this research, we explore Google Card Board to develop simulation game of raising pet. The Google Card Board is used to create view for the VR environment. The view and control in VR environment is built using Unity game engine. And the simulation process is designed using Finite State Machine (FSM). This FSM can help to design the process clearly. So the simulation process can describe the simulation of raising pet well. Raising pet is fun activity. But sometimes, there are many conditions which cause raising pet become difficult to do, i.e. environment condition, disease, high cost, etc. this research aims to explore and implement Google Card Board in simulation of raising pet.
ERIC Educational Resources Information Center
Thomas, Wayne W.; Boechler, Patricia M.
2014-01-01
With teachers taking more interest in utilizing 3D virtual environments for educational purposes, research is needed to understand how learners perceive and process information within virtual environments (Eschenbrenner, Nah, & Siau, 2008). In this study, the authors sought to determine if learning style or digital literacy predict incidental…
ERIC Educational Resources Information Center
Demirer, Veysel; Erbas, Cagdas
2016-01-01
This study aims to review studies on virtual learning environments in Turkey through the content analysis method. 63 studies consisting of thesis, articles and proceedings published in Turkish and English between 1996-2014 years were analyzed. It was observed that "Second Life" was mostly preferred as the virtual learning environment.…
ERIC Educational Resources Information Center
Murphrey, Theresa Pesl; Rutherford, Tracy A.; Doerfert, David L.; Edgar, Leslie D.; Edgar, Don W.
2014-01-01
Educational technology continues to expand with multi-user virtual environments (e.g., Second Life™) being the latest technology. Understanding a virtual environment's usability can enhance educational planning and effective use. Usability includes the interaction quality between an individual and the item being assessed. The purpose was to assess…
ERIC Educational Resources Information Center
Coffey, Amy Jo; Kamhawi, Rasha; Fishwick, Paul; Henderson, Julie
2017-01-01
Relatively few studies have empirically tested computer-based immersive virtual environments' efficacy in teaching or enhancing pro-social attitudes, such as intercultural sensitivity. This channel study experiment was conducted (N = 159) to compare what effects, if any, an immersive 3D virtual environment would have upon subjects' intercultural…
ERIC Educational Resources Information Center
Bakas, Christos; Mikropoulos, Tassos A.
2003-01-01
Explains the design and development of an educational virtual environment to support the teaching of planetary phenomena, particularly the movements of Earth and the sun, day and night cycle, and change of seasons. Uses an interactive, three-dimensional (3D) virtual environment. Initial results show that the majority of students enthused about…
ERIC Educational Resources Information Center
Ferrer-Garcia, Marta; Gutierrez-Maldonado, Jose; Caqueo-Urizar, Alejandra; Moreno, Elena
2009-01-01
This article explores the efficacy of virtual environments representing situations that are emotionally significant to patients with eating disorders (ED) to modify depression and anxiety levels both in these patients and in controls. Eighty-five ED patients and 108 students were randomly exposed to five experimental virtual environments (a…
ERIC Educational Resources Information Center
Standen, P. J.; Brown, D. J.; Cromby, J. J.
2001-01-01
Reviews the use of one type of computer software, virtual environments, for its potential in the education and rehabilitation of people with intellectual disabilities. Topics include virtual environments in special education; transfer of learning; adult learning; the role of the tutor; and future directions, including availability, accessibility,…
ERIC Educational Resources Information Center
Martinez, Guadalupe; Naranjo, Francisco L.; Perez, Angel L.; Suero, Maria Isabel; Pardo, Pedro J.
2011-01-01
This study compared the educational effects of computer simulations developed in a hyper-realistic virtual environment with the educational effects of either traditional schematic simulations or a traditional optics laboratory. The virtual environment was constructed on the basis of Java applets complemented with a photorealistic visual output.…
ERIC Educational Resources Information Center
Barkand, Jonathan; Kush, Joseph
2009-01-01
Virtual Learning Environments (VLEs) are becoming increasingly popular in online education environments and have multiple pedagogical advantages over more traditional approaches to education. VLEs include 3D worlds where students can engage in simulated learning activities such as Second Life. According to Claudia L'Amoreaux at Linden Lab, "at…
ERIC Educational Resources Information Center
Barbalios, N.; Ioannidou, I.; Tzionas, P.; Paraskeuopoulos, S.
2013-01-01
This paper introduces a realistic 3D model supported virtual environment for environmental education, that highlights the importance of water resource sharing by focusing on the tragedy of the commons dilemma. The proposed virtual environment entails simulations that are controlled by a multi-agent simulation model of a real ecosystem consisting…
Learning in 3D Virtual Environments: Collaboration and Knowledge Spirals
ERIC Educational Resources Information Center
Burton, Brian G.; Martin, Barbara N.
2010-01-01
The purpose of this case study was to determine if learning occurred within a 3D virtual learning environment by determining if elements of collaboration and Nonaka and Takeuchi's (1995) knowledge spiral were present. A key portion of this research was the creation of a Virtual Learning Environment. This 3D VLE utilized the Torque Game Engine…
Virtual hand: a 3D tactile interface to virtual environments
NASA Astrophysics Data System (ADS)
Rogowitz, Bernice E.; Borrel, Paul
2008-02-01
We introduce a novel system that allows users to experience the sensation of touch in a computer graphics environment. In this system, the user places his/her hand on an array of pins, which is moved about space on a 6 degree-of-freedom robot arm. The surface of the pins defines a surface in the virtual world. This "virtual hand" can move about the virtual world. When the virtual hand encounters an object in the virtual world, the heights of the pins are adjusted so that they represent the object's shape, surface, and texture. A control system integrates pin and robot arm motions to transmit information about objects in the computer graphics world to the user. It also allows the user to edit, change and move the virtual objects, shapes and textures. This system provides a general framework for touching, manipulating, and modifying objects in a 3-D computer graphics environment, which may be useful in a wide range of applications, including computer games, computer aided design systems, and immersive virtual worlds.
NASA Technical Reports Server (NTRS)
Lehnert, H.; Blauert, Jens; Pompetzki, W.
1991-01-01
In every-day listening the auditory event perceived by a listener is determined not only by the sound signal that a sound emits but also by a variety of environmental parameters. These parameters are the position, orientation and directional characteristics of the sound source, the listener's position and orientation, the geometrical and acoustical properties of surfaces which affect the sound field and the sound propagation properties of the surrounding fluid. A complete set of these parameters can be called an Acoustic Environment. If the auditory event perceived by a listener is manipulated in such a way that the listener is shifted acoustically into a different acoustic environment without moving himself physically, a Virtual Acoustic Environment has been created. Here, we deal with a special technique to set up nearly arbitrary Virtual Acoustic Environments, the Binaural Room Simulation. The purpose of the Binaural Room Simulation is to compute the binaural impulse response related to a virtual acoustic environment taking into account all parameters mentioned above. One possible way to describe a Virtual Acoustic Environment is the concept of the virtual sound sources. Each of the virtual sources emits a certain signal which is correlated but not necessarily identical with the signal emitted by the direct sound source. If source and receiver are non moving, the acoustic environment becomes a linear time-invariant system. Then, the Binaural Impulse Response from the source to a listener' s eardrums contains all relevant auditory information related to the Virtual Acoustic Environment. Listening into the simulated environment can easily be achieved by convolving the Binaural Impulse Response with dry signals and representing the results via headphones.
Massetti, Thais; Fávero, Francis Meire; Menezes, Lilian Del Ciello de; Alvarez, Mayra Priscila Boscolo; Crocetta, Tânia Brusque; Guarnieri, Regiani; Nunes, Fátima L S; Monteiro, Carlos Bandeira de Mello; Silva, Talita Dias da
2018-04-01
To evaluate whether people with Duchenne muscular dystrophy (DMD) practicing a task in a virtual environment could improve performance given a similar task in a real environment, as well as distinguishing whether there is transference between performing the practice in virtual environment and then a real environment and vice versa. Twenty-two people with DMD were evaluated and divided into two groups. The goal was to reach out and touch a red cube. Group A began with the real task and had to touch a real object, and Group B began with the virtual task and had to reach a virtual object using the Kinect system. ANOVA showed that all participants decreased the movement time from the first (M = 973 ms) to the last block of acquisition (M = 783 ms) in both virtual and real tasks and motor learning could be inferred by the short-term retention and transfer task (with increasing distance of the target). However, the evaluation of task performance demonstrated that the virtual task provided an inferior performance when compared to the real task in all phases of the study, and there was no effect for sequence. Both virtual and real tasks promoted improvement of performance in the acquisition phase, short-term retention, and transfer. However, there was no transference of learning between environments. In conclusion, it is recommended that the use of virtual environments for individuals with DMD needs to be considered carefully.
ERIC Educational Resources Information Center
Kraemer, David J. M.; Schinazi, Victor R.; Cawkwell, Philip B.; Tekriwal, Anand; Epstein, Russell A.; Thompson-Schill, Sharon L.
2017-01-01
Using novel virtual cities, we investigated the influence of verbal and visual strategies on the encoding of navigation-relevant information in a large-scale virtual environment. In 2 experiments, participants watched videos of routes through 4 virtual cities and were subsequently tested on their memory for observed landmarks and their ability to…
Virtual agents in a simulated virtual training environment
NASA Technical Reports Server (NTRS)
Achorn, Brett; Badler, Norman L.
1993-01-01
A drawback to live-action training simulations is the need to gather a large group of participants in order to train a few individuals. One solution to this difficulty is the use of computer-controlled agents in a virtual training environment. This allows a human participant to be replaced by a virtual, or simulated, agent when only limited responses are needed. Each agent possesses a specified set of behaviors and is capable of limited autonomous action in response to its environment or the direction of a human trainee. The paper describes these agents in the context of a simulated hostage rescue training session, involving two human rescuers assisted by three virtual (computer-controlled) agents and opposed by three other virtual agents.
Headphone and Head-Mounted Visual Displays for Virtual Environments
NASA Technical Reports Server (NTRS)
Begault, Duran R.; Ellis, Stephen R.; Wenzel, Elizabeth M.; Trejo, Leonard J. (Technical Monitor)
1998-01-01
A realistic auditory environment can contribute to both the overall subjective sense of presence in a virtual display, and to a quantitative metric predicting human performance. Here, the role of audio in a virtual display and the importance of auditory-visual interaction are examined. Conjectures are proposed regarding the effectiveness of audio compared to visual information for creating a sensation of immersion, the frame of reference within a virtual display, and the compensation of visual fidelity by supplying auditory information. Future areas of research are outlined for improving simulations of virtual visual and acoustic spaces. This paper will describe some of the intersensory phenomena that arise during operator interaction within combined visual and auditory virtual environments. Conjectures regarding audio-visual interaction will be proposed.
Training in virtual environments: putting theory into practice.
Moskaliuk, Johannes; Bertram, Johanna; Cress, Ulrike
2013-01-01
Virtual training environments are used when training in reality is challenging because of the high costs, danger, time or effort involved. In this paper we argue for a theory-driven development of such environments, with the aim of connecting theory to practice and ensuring that the training provided fits the needs of the trained persons and their organisations. As an example, we describe the development of VirtualPolice (ViPOL), a training environment for police officers in a federal state of Germany. We provided the theoretical foundation for ViPOL concerning the feeling of being present, social context, learning motivation and perspective-taking. We developed a framework to put theory into practice. To evaluate our framework we interviewed the stakeholders of ViPOL and surveyed current challenges and limitations of virtual training. The results led to a review of a theory-into-practice framework which is presented in the conclusion. Feeling of presence, social context, learning motivation and perspective-taking are relevant for training in virtual environments. The theory-into-practice framework presented here supports developers and trainers in implementing virtual training tools. The framework was validated with an interview study of stakeholders of a virtual training project. We identified limitations, opportunities and challenges.
NASA Astrophysics Data System (ADS)
Abakumov, Evgeny
2016-04-01
Physical properties of the soils of the cold environments are underestimated. Soil and permafrost border and active layer thickness are the key classification indicators for the polar soils. That is why electrophysical research has been conducted with aim to determine the soil-permafrost layer heterogeneity and the depth of the uppermost permafrost layer on examples of selected plots in Antarctic region and Russian Arctic. The electric resistivity (ER) was measured directly in the soil profiles using the vertical electrical sounding (VERS) method, which provides data on the changes in the electrical resistivity throughout the profile from the soil surface without digging pits or drilling. This method allows dividing the soil layer vertically into genetic layers, which are different on main key properties and characteristics Different soil layers have different ER values, that is why the sharp changes in ER values in soil profile can be interpreted as results of transition of one horizon to another. In our study, the resistivity measurements were performed using four-electrode (AB + MN) arrays of the AMNB configuration with use of the Schlumberger geometry. A Landmapper ERM-03 instrument (Landviser, USA) was used for the VES measurements in this study. Electrodes were situated on the soil surface, distance between M and N was fixes, while distance from A to B were changed during the sounding. Vertical Electrical Resistivity Soundings (VERS) using Schlumberger array were carried out at stations, situated on the different plots of terrestrial ecosystems of Arctic and Antarctic. The resistance readings at every VERS point were automatically displayed on the digital readout screen and then written down on the field note book. The soils had been 'sounded' thoroughly and found to vary between 5 cm and 3-5 m in A-B distances. It was shown that use of VES methodology in soil survey is quite useful for identification of the permafrost depth without digging of soil pit. This method allow identify soil heterogeneity, because the ER values are strongly affected by soil properties and intensively changes on the border of different geochemical regimes, i.e. on the border of active layer and permafrost. VES data obtained show that the upper border of the permafrost layer coincides with that border, which were identified in field on the base of soil profile morphology. The VERS method also can used for identification of Gleyic, Histic and Podzolic layers. It has been also shown that permafrost layer is less homogenous in upper part of permafrost, than in lower one. It is caused by number of cracks, channels and other paths of dissolved organic matter and iron containing compounds migration. VES methodology is useful for preliminary soil survey in the regions with permafrost affected soil cover. It is also can be applied for detalization of soil-permafrost layer stratification in field soil pits.
Gokeler, Alli; Bisschop, Marsha; Myer, Gregory D; Benjaminse, Anne; Dijkstra, Pieter U; van Keeken, Helco G; van Raay, Jos J A M; Burgerhof, Johannes G M; Otten, Egbert
2016-07-01
The purpose of this study was to evaluate the influence of immersion in a virtual reality environment on knee biomechanics in patients after ACL reconstruction (ACLR). It was hypothesized that virtual reality techniques aimed to change attentional focus would influence altered knee flexion angle, knee extension moment and peak vertical ground reaction force (vGRF) in patients following ACLR. Twenty athletes following ACLR and 20 healthy controls (CTRL) performed a step-down task in both a non-virtual reality environment and a virtual reality environment displaying a pedestrian traffic scene. A motion analysis system and force plates were used to measure kinematics and kinetics during a step-down task to analyse each single-leg landing. A significant main effect was found for environment for knee flexion excursion (P = n.s.). Significant interaction differences were found between environment and groups for vGRF (P = 0.004), knee moment (P < 0.001), knee angle at peak vGRF (P = 0.01) and knee flexion excursion (P = 0.03). There was larger effect of virtual reality environment on knee biomechanics in patients after ACLR compared with controls. Patients after ACLR immersed in virtual reality environment demonstrated knee joint biomechanics that approximate those of CTRL. The results of this study indicate that a realistic virtual reality scenario may distract patients after ACLR from conscious motor control. Application of clinically available technology may aid in current rehabilitation programmes to target altered movement patterns after ACLR. Diagnostic study, Level III.
Virtual environments special needs and evaluative methods.
Brown, D J; Standen, P J; Cobb, S V
1998-01-01
This paper presents an overview of the development of the Learning in Virtual Environments programme (LIVE), carried out in special education over the last four years. It is more precisely a project chronology, so that the reader can sense the historical development of the programme rather than giving emphasis to any one particular feature or breakthrough, which are covered in other papers and available through the authors. The project conception in a special school in Nottingham is followed by a description of the development of experiential and communicational virtual learning environments. These are followed, in turn, by the results of our testing programmes which show that experience gained in a virtual environment can transfer to the real world and that their use can encourage self-directed activity in students with severe learning difficulties. Also included is a discussion of the role of virtual learning environments (VLEs) in special education and of its attributes in the context of contemporary educational theory.
NASA Astrophysics Data System (ADS)
Simonnet, Mathieu; Jacobson, Dan; Vieilledent, Stephane; Tisseau, Jacques
Navigating consists of coordinating egocentric and allocentric spatial frames of reference. Virtual environments have afforded researchers in the spatial community with tools to investigate the learning of space. The issue of the transfer between virtual and real situations is not trivial. A central question is the role of frames of reference in mediating spatial knowledge transfer to external surroundings, as is the effect of different sensory modalities accessed in simulated and real worlds. This challenges the capacity of blind people to use virtual reality to explore a scene without graphics. The present experiment involves a haptic and auditory maritime virtual environment. In triangulation tasks, we measure systematic errors and preliminary results show an ability to learn configurational knowledge and to navigate through it without vision. Subjects appeared to take advantage of getting lost in an egocentric “haptic” view in the virtual environment to improve performances in the real environment.
Seeing ahead: experience and language in spatial perspective.
Alloway, Tracy Packiam; Corley, Martin; Ramscar, Michael
2006-03-01
Spatial perspective can be directed by various reference frames, as well as by the direction of motion. In the present study, we explored how ambiguity in spatial tasks can be resolved. Participants were presented with virtual reality environments in order to stimulate a spatialreference frame based on motion. They interacted with an ego-moving spatial system in Experiment 1 and an object-moving spatial system in Experiment 2. While interacting with the virtual environment, the participants were presented with either a question representing a motion system different from that of the virtual environment or a nonspatial question relating to physical features of the virtual environment. They then performed the target task assign the label front in an ambiguous spatial task. The findings indicate that the disambiguation of spatial terms can be influenced by embodied experiences, as represented by the virtual environment, as well as by linguistic context.
NASA Technical Reports Server (NTRS)
1994-01-01
This symposium on measurement and control in robotics included sessions on: (1) rendering, including tactile perception and applied virtual reality; (2) applications in simulated medical procedures and telerobotics; (3) tracking sensors in a virtual environment; (4) displays for virtual reality applications; (5) sensory feedback including a virtual environment application with partial gravity simulation; and (6) applications in education, entertainment, technical writing, and animation.
[The use of virtual learning environment in teaching basic and advanced life support].
Cogo, Ana Luísa Petersen; Silveira, Denise Tolfo; Lírio, Aline de Morais; Severo, Carolina Lopes
2003-12-01
The present paper is the result of an experiment conducted as part of the Nursing: basic and advanced life support course, which was offered as a semi-online course using the virtual learning environment called Learning Space. The virtual learning environment optimizes classroom dynamics, since in the classroom setting, practical activities may be privileged; besides, learning is customized as students may access the environment whenever and wherever they wish.
Verification of Emmert's law in actual and virtual environments.
Nakamizo, Sachio; Imamura, Mariko
2004-11-01
We examined Emmert's law by measuring the perceived size of an afterimage and the perceived distance of the surface on which the afterimage was projected in actual and virtual environments. The actual environment consisted of a corridor with ample cues as to distance and depth. The virtual environment was made from the CAVE of a virtual reality system. The afterimage, disc-shaped and one degree in diameter, was produced by flashing with an electric photoflash. The observers were asked to estimate the perceived distance to surfaces located at various physical distances (1 to 24 m) by the magnitude estimation method and to estimate the perceived size of the afterimage projected on the surfaces by a matching method. The results show that the perceived size of the afterimage was directly proportional to the perceived distance in both environments; thus, Emmert's law holds in virtual as well as actual environments. We suggest that Emmert's law is a specific case of a functional principle of distance scaling by the visual system.
Effects of optokinetic stimulation induced by virtual reality on locomotion: a preliminary study.
Ohyama, Seizo; Nishiike, Suetaka; Watanabe, Hiroshi; Matsuoka, Katsunori; Takeda, Noriaki
2008-11-01
Exposure to a virtual environment for 20 min was sufficient to cause adaptive changes in locomotion in healthy subjects, suggesting that virtual environments might improve locomotor deviation in patients with unilateral labyrinthine defects. Postural and locomotor control in patients with unilateral labyrinthine defects deviates towards the lesion side. The aim of this study was to examine whether active locomotion within a virtual environment can increase the functionality of rehabilitation. We examined the effects of optokinetic stimulation produced by a virtual reality environment on ocular movement and locomotor tracks in 10 healthy subjects. During the 20 min experiment, the mean locomotor deviation and the mean frequency and mean amplitude of optokinetic nystagmus during the last period of the experiment were significantly higher than those during the initial period.
2017-08-08
Usability Studies In Virtual And Traditional Computer Aided Design Environments For Fault Identification Dr. Syed Adeel Ahmed, Xavier University...virtual environment with wand interfaces compared directly with a workstation non-stereoscopic traditional CAD interface with keyboard and mouse. In...the differences in interaction when compared with traditional human computer interfaces. This paper provides analysis via usability study methods
ERIC Educational Resources Information Center
Bailenson, Jeremy N.; Yee, Nick; Blascovich, Jim; Beall, Andrew C.; Lundblad, Nicole; Jin, Michael
2008-01-01
This article illustrates the utility of using virtual environments to transform social interaction via behavior and context, with the goal of improving learning in digital environments. We first describe the technology and theories behind virtual environments and then report data from 4 empirical studies. In Experiment 1, we demonstrated that…
Instructional Features for Training in Virtual Environments
2006-07-01
Technical Report 1184 Instructional Features for Training in Virtual Environments Michael J. Singer U. S. Army Research Institute Jason P. Kring...Report 1184 Instructional Features for Training in Virtual Environments Michael J. Singer U. S. Army Research Institute Jason P. Kring University of...provides in comparison to traditional, real world experience training programs (Hays & Singer , 1989; Swezey & Andrews, 2001). First, as with the
Human Machine Interfaces for Teleoperators and Virtual Environments
NASA Technical Reports Server (NTRS)
Durlach, Nathaniel I. (Compiler); Sheridan, Thomas B. (Compiler); Ellis, Stephen R. (Compiler)
1991-01-01
In Mar. 1990, a meeting organized around the general theme of teleoperation research into virtual environment display technology was conducted. This is a collection of conference-related fragments that will give a glimpse of the potential of the following fields and how they interplay: sensorimotor performance; human-machine interfaces; teleoperation; virtual environments; performance measurement and evaluation methods; and design principles and predictive models.
ERIC Educational Resources Information Center
Zeichner, Orit; Zilka, Gila
2016-01-01
This study focused on feelings of threat and challenge among pre-service teachers in different learning environments--virtual and blended courses. The two goals of this study were (1) to define the subjects' feelings in virtual and blended learning environments, and the relationship between them, and (2) to examine how their feelings changed…
Virtual Golden Foods Corporation: Generic Skills in a Virtual Crisis Environment (A Pilot Study)
ERIC Educational Resources Information Center
Godat, Meredith
2007-01-01
Workplace learning in a crisis-rich environment is often difficult if not impossible to integrate into programs so that students are able to experience and apply crisis management practices and principles. This study presents the results of a pilot project that examined the effective use of a virtual reality (VR) environment as a tool to teach…
NASA Technical Reports Server (NTRS)
Ellis, Stephen R.
1991-01-01
Natural environments have a content, i.e., the objects in them; a geometry, i.e., a pattern of rules for positioning and displacing the objects; and a dynamics, i.e., a system of rules describing the effects of forces acting on the objects. Human interaction with most common natural environments has been optimized by centuries of evolution. Virtual environments created through the human-computer interface similarly have a content, geometry, and dynamics, but the arbitrary character of the computer simulation creating them does not insure that human interaction with these virtual environments will be natural. The interaction, indeed, could be supernatural but it also could be impossible. An important determinant of the comprehensibility of a virtual environment is the correspondence between the environmental frames of reference and those associated with the control of environmental objects. The effects of rotation and displacement of control frames of reference with respect to corresponding environmental references differ depending upon whether perceptual judgement or manual tracking performance is measured. The perceptual effects of frame of reference displacement may be analyzed in terms of distortions in the process of virtualizing the synthetic environment space. The effects of frame of reference displacement and rotation have been studied by asking subjects to estimate exocentric direction in a virtual space.
NASA Technical Reports Server (NTRS)
1990-01-01
While a new technology called 'virtual reality' is still at the 'ground floor' level, one of its basic components, 3D computer graphics is already in wide commercial use and expanding. Other components that permit a human operator to 'virtually' explore an artificial environment and to interact with it are being demonstrated routinely at Ames and elsewhere. Virtual reality might be defined as an environment capable of being virtually entered - telepresence, it is called - or interacted with by a human. The Virtual Interface Environment Workstation (VIEW) is a head-mounted stereoscopic display system in which the display may be an artificial computer-generated environment or a real environment relayed from remote video cameras. Operator can 'step into' this environment and interact with it. The DataGlove has a series of fiber optic cables and sensors that detect any movement of the wearer's fingers and transmit the information to a host computer; a computer generated image of the hand will move exactly as the operator is moving his gloved hand. With appropriate software, the operator can use the glove to interact with the computer scene by grasping an object. The DataSuit is a sensor equipped full body garment that greatly increases the sphere of performance for virtual reality simulations.
Novel Virtual Environment for Alternative Treatment of Children with Cerebral Palsy
de Oliveira, Juliana M.; Fernandes, Rafael Carneiro G.; Pinto, Cristtiano S.; Pinheiro, Plácido R.; Ribeiro, Sidarta
2016-01-01
Cerebral palsy is a severe condition usually caused by decreased brain oxygenation during pregnancy, at birth or soon after birth. Conventional treatments for cerebral palsy are often tiresome and expensive, leading patients to quit treatment. In this paper, we describe a virtual environment for patients to engage in a playful therapeutic game for neuropsychomotor rehabilitation, based on the experience of the occupational therapy program of the Nucleus for Integrated Medical Assistance (NAMI) at the University of Fortaleza, Brazil. Integration between patient and virtual environment occurs through the hand motion sensor “Leap Motion,” plus the electroencephalographic sensor “MindWave,” responsible for measuring attention levels during task execution. To evaluate the virtual environment, eight clinical experts on cerebral palsy were subjected to a questionnaire regarding the potential of the experimental virtual environment to promote cognitive and motor rehabilitation, as well as the potential of the treatment to enhance risks and/or negatively influence the patient's development. Based on the very positive appraisal of the experts, we propose that the experimental virtual environment is a promising alternative tool for the rehabilitation of children with cerebral palsy. PMID:27403154
Lehtinen, Matti; Söderlund-Strand, Anna; Vänskä, Simopekka; Luostarinen, Tapio; Eriksson, Tiina; Natunen, Kari; Apter, Dan; Baussano, Iacopo; Harjula, Katja; Hokkanen, Mari; Kuortti, Marjo; Palmroth, Johanna; Petäjä, Tiina; Pukkala, Eero; Rekonen, Sirpa; Siitari-Mattila, Mari; Surcel, Heljä-Marja; Tuomivaara, Leena; Paavonen, Jorma; Dillner, Joakim; Dubin, Gary; Garnett, Geoffrey
2018-03-01
Human papillomavirus (HPV) vaccine is efficacious but the real-life effectiveness of gender-neutral and girls-only vaccination strategies is unknown. We report a community-randomized trial on the protective effectiveness [(PE) = vaccine efficacy (VE) + herd effect (HE)] of the two strategies among females in virtually HPV vaccination naïve population. We randomized 33 Finnish communities into Arm A) gender-neutral vaccination with AS04-adjuvanted HPV16/18 vaccine (11 communities), Arm B) HPV vaccination of girls and hepatitis B-virus (HBV) vaccination of boys (11 communities) or Arm C) gender-neutral HBV vaccination (11 communities). All resident 39,420 females and 40,852 males born 1992-95 were invited in 2007-09. Virtually all (99%) 12- to 15-year-old participating males (11,662) and females (20,513) received three doses resulting in uniform 20-30% male and 50% female vaccination coverage by birth cohort. Four years later (2010-14) 11,396 cervicovaginal samples obtained from 18.5 year-old women were tested for HPV DNA, and prevalence of cervical HPV infections by trial arm and birth cohort was the main outcome measure. VEs against HPV16/18 varied between 89.2% and 95.2% across birth cohorts in arms A and B. The VEs against non-vaccine types consistent with cross-protection were highest in those born 1994-95 for HPV45 (VE A 82.8%; VE B 86.1%) and for HPV31 (VE A 77.6%, VE B 84.6%). The HEs in the non HPV-vaccinated were statistically significant in those born 1994-95 for HPV18 (HE A 51.0%; 95% CI 8.3-73.8, HE B 47.2%; 6.5-70.2) and for HPV31/33 in arm A (HE A 53.7%; 22.1-72.5). For HPV16 and 45 no significant herd effects were detected. PE estimates against HPV16/18 were similar by both strategies (PE A 58.1%; 45.1-69.4; PE B 55.7%; 42.9-66.6). PE estimates against HPV31/33 were higher by the gender-neutral vaccination (PE A 60.5%; 43.6-73.4; PE B 44.5%; 24.9-60.6). In conclusion, while gender-neutral strategy enhanced the effectiveness of HPV vaccination for cross-protected HPV types with low to moderate coverage, high coverage in males appears to be key to providing a substantial public health benefit also to unvaccinated females. Trial registration www.clinicaltrials.gov.com NCT000534638. © 2017 UICC.
Physical environment virtualization for human activities recognition
NASA Astrophysics Data System (ADS)
Poshtkar, Azin; Elangovan, Vinayak; Shirkhodaie, Amir; Chan, Alex; Hu, Shuowen
2015-05-01
Human activity recognition research relies heavily on extensive datasets to verify and validate performance of activity recognition algorithms. However, obtaining real datasets are expensive and highly time consuming. A physics-based virtual simulation can accelerate the development of context based human activity recognition algorithms and techniques by generating relevant training and testing videos simulating diverse operational scenarios. In this paper, we discuss in detail the requisite capabilities of a virtual environment to aid as a test bed for evaluating and enhancing activity recognition algorithms. To demonstrate the numerous advantages of virtual environment development, a newly developed virtual environment simulation modeling (VESM) environment is presented here to generate calibrated multisource imagery datasets suitable for development and testing of recognition algorithms for context-based human activities. The VESM environment serves as a versatile test bed to generate a vast amount of realistic data for training and testing of sensor processing algorithms. To demonstrate the effectiveness of VESM environment, we present various simulated scenarios and processed results to infer proper semantic annotations from the high fidelity imagery data for human-vehicle activity recognition under different operational contexts.
ERIC Educational Resources Information Center
Huang, Hsiu-Mei; Liaw, Shu-Sheng; Lai, Chung-Min
2016-01-01
Advanced technologies have been widely applied in medical education, including human-patient simulators, immersive virtual reality Cave Automatic Virtual Environment systems, and video conferencing. Evaluating learner acceptance of such virtual reality (VR) learning environments is a critical issue for ensuring that such technologies are used to…
ERIC Educational Resources Information Center
Liu, Chang; Zhong, Ying; Ozercan, Sertac; Zhu, Qing
2013-01-01
This paper presents a template-based solution to overcome technical barriers non-technical computer end users face when developing functional learning environments in three-dimensional virtual worlds (3DVW). "iVirtualWorld," a prototype of a platform-independent 3DVW creation tool that implements the proposed solution, facilitates 3DVW…
ERIC Educational Resources Information Center
Annetta, Leonard; Klesath, Marta; Meyer, John
2009-01-01
A 3-D virtual field trip was integrated into an online college entomology course and developed as a trial for the possible incorporation of future virtual environments to supplement online higher education laboratories. This article provides an explanation of the rationale behind creating the virtual experience, the Bug Farm; the method and…
Pre-Service Teachers' Perspectives on Using Scenario-Based Virtual Worlds in Science Education
ERIC Educational Resources Information Center
Kennedy-Clark, Shannon
2011-01-01
This paper presents the findings of a study on the current knowledge and attitudes of pre-service teachers on the use of scenario-based multi-user virtual environments in science education. The 28 participants involved in the study were introduced to "Virtual Singapura," a multi-user virtual environment, and completed an open-ended questionnaire.…
Introducing and Evaluating the Behavior of Non-Verbal Features in the Virtual Learning
ERIC Educational Resources Information Center
Dharmawansa, Asanka D.; Fukumura, Yoshimi; Marasinghe, Ashu; Madhuwanthi, R. A. M.
2015-01-01
The objective of this research is to introduce the behavior of non-verbal features of e-Learners in the virtual learning environment to establish a fair representation of the real user by an avatar who represents the e-Learner in the virtual environment and to distinguish the deportment of the non-verbal features during the virtual learning…
ERIC Educational Resources Information Center
Harrington, M. C. R.
2011-01-01
Over the past 20 years, there has been a debate on the effectiveness of virtual reality used for learning with young children, producing many ideas but little empirical proof. This empirical study compared learning activity in situ of a real environment (Real) and a desktop virtual reality (Virtual) environment, built with video game technology,…
Virtual reality environments for post-stroke arm rehabilitation.
Subramanian, Sandeep; Knaut, Luiz A; Beaudoin, Christian; McFadyen, Bradford J; Feldman, Anatol G; Levin, Mindy F
2007-06-22
Optimal practice and feedback elements are essential requirements for maximal motor recovery in patients with motor deficits due to central nervous system lesions. A virtual environment (VE) was created that incorporates practice and feedback elements necessary for maximal motor recovery. It permits varied and challenging practice in a motivating environment that provides salient feedback. The VE gives the user knowledge of results feedback about motor behavior and knowledge of performance feedback about the quality of pointing movements made in a virtual elevator. Movement distances are related to length of body segments. We describe an immersive and interactive experimental protocol developed in a virtual reality environment using the CAREN system. The VE can be used as a training environment for the upper limb in patients with motor impairments.
NASA Technical Reports Server (NTRS)
Hammrs, Stephan R.
2008-01-01
Virtual Satellite (VirtualSat) is a computer program that creates an environment that facilitates the development, verification, and validation of flight software for a single spacecraft or for multiple spacecraft flying in formation. In this environment, enhanced functionality and autonomy of navigation, guidance, and control systems of a spacecraft are provided by a virtual satellite that is, a computational model that simulates the dynamic behavior of the spacecraft. Within this environment, it is possible to execute any associated software, the development of which could benefit from knowledge of, and possible interaction (typically, exchange of data) with, the virtual satellite. Examples of associated software include programs for simulating spacecraft power and thermal- management systems. This environment is independent of the flight hardware that will eventually host the flight software, making it possible to develop the software simultaneously with, or even before, the hardware is delivered. Optionally, by use of interfaces included in VirtualSat, hardware can be used instead of simulated. The flight software, coded in the C or C++ programming language, is compilable and loadable into VirtualSat without any special modifications. Thus, VirtualSat can serve as a relatively inexpensive software test-bed for development test, integration, and post-launch maintenance of spacecraft flight software.
Future Evolution of Virtual Worlds as Communication Environments
NASA Astrophysics Data System (ADS)
Prisco, Giulio
Extensive experience creating locations and activities inside virtual worlds provides the basis for contemplating their future. Users of virtual worlds are diverse in their goals for these online environments; for example, immersionists want them to be alternative realities disconnected from real life, whereas augmentationists want them to be communication media supporting real-life activities. As the technology improves, the diversity of virtual worlds will increase along with their significance. Many will incorporate more advanced virtual reality, or serve as major media for long-distance collaboration, or become the venues for futurist social movements. Key issues are how people can create their own virtual worlds, travel across worlds, and experience a variety of multimedia immersive environments. This chapter concludes by noting the view among some computer scientists that future technologies will permit uploading human personalities to artificial intelligence avatars, thereby enhancing human beings and rendering the virtual worlds entirely real.
Agreements in Virtual Organizations
NASA Astrophysics Data System (ADS)
Pankowska, Malgorzata
This chapter is an attempt to explain the important impact that contract theory delivers with respect to the concept of virtual organization. The author believes that not enough research has been conducted in order to transfer theoretical foundations for networking to the phenomena of virtual organizations and open autonomic computing environment to ensure the controllability and management of them. The main research problem of this chapter is to explain the significance of agreements for virtual organizations governance. The first part of this chapter comprises explanations of differences among virtual machines and virtual organizations for further descriptions of the significance of the first ones to the development of the second. Next, the virtual organization development tendencies are presented and problems of IT governance in highly distributed organizational environment are discussed. The last part of this chapter covers analysis of contracts and agreements management for governance in open computing environments.
Exploring a novel environment improves motivation and promotes recall of words.
Schomaker, Judith; van Bronkhorst, Marthe L V; Meeter, Martijn
2014-01-01
Active exploration of novel environments is known to increase plasticity in animals, promoting long-term potentiation in the hippocampus and enhancing memory formation. These effects can occur during as well as after exploration. In humans novelty's effects on memory have been investigated with other methods, but never in an active exploration paradigm. We therefore investigated whether active spatial exploration of a novel compared to a previously familiarized virtual environment promotes performance on an unrelated word learning task. Exploration of the novel environment enhanced recall, generally thought to be hippocampus-dependent, but not recognition, believed to rely less on the hippocampus. Recall was better for participants that gave higher presence ratings for their experience in the virtual environment. These ratings were higher for the novel compared to the familiar virtual environment, suggesting that novelty increased attention for the virtual rather than real environment; however, this did not explain the effect of novelty on recall.
Virtual interface environment workstations
NASA Technical Reports Server (NTRS)
Fisher, S. S.; Wenzel, E. M.; Coler, C.; Mcgreevy, M. W.
1988-01-01
A head-mounted, wide-angle, stereoscopic display system controlled by operator position, voice and gesture has been developed at NASA's Ames Research Center for use as a multipurpose interface environment. This Virtual Interface Environment Workstation (VIEW) system provides a multisensory, interactive display environment in which a user can virtually explore a 360-degree synthesized or remotely sensed environment and can viscerally interact with its components. Primary applications of the system are in telerobotics, management of large-scale integrated information systems, and human factors research. System configuration, research scenarios, and research directions are described.
Altering User Movement Behaviour in Virtual Environments.
Simeone, Adalberto L; Mavridou, Ifigeneia; Powell, Wendy
2017-04-01
In immersive Virtual Reality systems, users tend to move in a Virtual Environment as they would in an analogous physical environment. In this work, we investigated how user behaviour is affected when the Virtual Environment differs from the physical space. We created two sets of four environments each, plus a virtual replica of the physical environment as a baseline. The first focused on aesthetic discrepancies, such as a water surface in place of solid ground. The second focused on mixing immaterial objects together with those paired to tangible objects. For example, barring an area with walls or obstacles. We designed a study where participants had to reach three waypoints laid out in such a way to prompt a decision on which path to follow based on the conflict between the mismatching visual stimuli and their awareness of the real layout of the room. We analysed their performances to determine whether their trajectories were altered significantly from the shortest route. Our results indicate that participants altered their trajectories in presence of surfaces representing higher walking difficulty (for example, water instead of grass). However, when the graphical appearance was found to be ambiguous, there was no significant trajectory alteration. The environments mixing immaterial with physical objects had the most impact on trajectories with a mean deviation from the shortest route of 60 cm against the 37 cm of environments with aesthetic alterations. The co-existance of paired and unpaired virtual objects was reported to support the idea that all objects participants saw were backed by physical props. From these results and our observations, we derive guidelines on how to alter user movement behaviour in Virtual Environments.
NASA Astrophysics Data System (ADS)
Jurdana-Šepić, R.; Poljančić Beljan, I.
Searching for T Tauri stars or related early type variables we carried out a BVRI photometric measurements of five candidates with positions within the field of the pre-main sequence object V733 Cephei (Persson's star) located in the dark cloud L1216 near to Cepheus OB3 Association: VES 946, VES 950, NSV 14333, NSV 25966 and V385 Cep. Their magnitudes are determined on the plates from Asiago Observatory historical photographic archive exposed 1971 - 1978. We provide finding charts for program stars and comparison sequence stars, magnitude estimations, magnitude mean values and BVR_cI_c light curves of program stars.
Report from the Field: Psychological First Aid for Haiti's Storm Orphans.
Giraldo, Gloria
2008-07-01
In 2004, the final death toll in Haiti from Tropical Storm Jeanne was recorded at 3,006; of these, 2,826 in Gonaïves, a city floating in ruins. The road to Gonaïves was washed out, leaving the city and the department of Artibonite cut off for days from the rest of the country. Dr Juan Carlos Ch�vez, who headed the Cuban medical team in Haiti at the time, recalls that 17 Cuban health professionals were working in the area when the storm barrelled through, among the 400 already serving in the country. They were later joined by another 72 doctors, nurses, technicians and engineers sent directly from Cuba.
Using voice input and audio feedback to enhance the reality of a virtual experience
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miner, N.E.
1994-04-01
Virtual Reality (VR) is a rapidly emerging technology which allows participants to experience a virtual environment through stimulation of the participant`s senses. Intuitive and natural interactions with the virtual world help to create a realistic experience. Typically, a participant is immersed in a virtual environment through the use of a 3-D viewer. Realistic, computer-generated environment models and accurate tracking of a participant`s view are important factors for adding realism to a virtual experience. Stimulating a participant`s sense of sound and providing a natural form of communication for interacting with the virtual world are equally important. This paper discusses the advantagesmore » and importance of incorporating voice recognition and audio feedback capabilities into a virtual world experience. Various approaches and levels of complexity are discussed. Examples of the use of voice and sound are presented through the description of a research application developed in the VR laboratory at Sandia National Laboratories.« less
ERIC Educational Resources Information Center
Paulsson, Fredrik; Naeve, Ambjorn
2006-01-01
Based on existing Learning Object taxonomies, this article suggests an alternative Learning Object taxonomy, combined with a general Service Oriented Architecture (SOA) framework, aiming to transfer the modularized concept of Learning Objects to modularized Virtual Learning Environments. The taxonomy and SOA-framework exposes a need for a clearer…
NASA Astrophysics Data System (ADS)
Schmeil, Andreas; Eppler, Martin J.
Despite the fact that virtual worlds and other types of multi-user 3D collaboration spaces have long been subjects of research and of application experiences, it still remains unclear how to best benefit from meeting with colleagues and peers in a virtual environment with the aim of working together. Making use of the potential of virtual embodiment, i.e. being immersed in a space as a personal avatar, allows for innovative new forms of collaboration. In this paper, we present a framework that serves as a systematic formalization of collaboration elements in virtual environments. The framework is based on the semiotic distinctions among pragmatic, semantic and syntactic perspectives. It serves as a blueprint to guide users in designing, implementing, and executing virtual collaboration patterns tailored to their needs. We present two team and two community collaboration pattern examples as a result of the application of the framework: Virtual Meeting, Virtual Design Studio, Spatial Group Configuration, and Virtual Knowledge Fair. In conclusion, we also point out future research directions for this emerging domain.
Perfecting scientists’ collaboration and problem-solving skills in the virtual team environment
USDA-ARS?s Scientific Manuscript database
Perfecting Scientists’ Collaboration and Problem-Solving Skills in the Virtual Team Environment Numerous factors have contributed to the proliferation of conducting work in virtual teams at the domestic, national, and global levels: innovations in technology, critical developments in software, co-lo...
Virtual Reality Calibration for Telerobotic Servicing
NASA Technical Reports Server (NTRS)
Kim, W.
1994-01-01
A virtual reality calibration technique of matching a virtual environment of simulated graphics models in 3-D geometry and perspective with actual camera views of the remote site task environment has been developed to enable high-fidelity preview/predictive displays with calibrated graphics overlay on live video.
ERIC Educational Resources Information Center
Schwienhorst, Klaus
2002-01-01
Discussion of computer-assisted language learning focuses on the benefits of virtual reality environments, particularly for foreign language contexts. Topics include three approaches to learner autonomy; supporting reflection, including self-awareness; supporting interaction, including collaboration; and supporting experimentation, including…
Towards Gesture-Based Multi-User Interactions in Collaborative Virtual Environments
NASA Astrophysics Data System (ADS)
Pretto, N.; Poiesi, F.
2017-11-01
We present a virtual reality (VR) setup that enables multiple users to participate in collaborative virtual environments and interact via gestures. A collaborative VR session is established through a network of users that is composed of a server and a set of clients. The server manages the communication amongst clients and is created by one of the users. Each user's VR setup consists of a Head Mounted Display (HMD) for immersive visualisation, a hand tracking system to interact with virtual objects and a single-hand joypad to move in the virtual environment. We use Google Cardboard as a HMD for the VR experience and a Leap Motion for hand tracking, thus making our solution low cost. We evaluate our VR setup though a forensics use case, where real-world objects pertaining to a simulated crime scene are included in a VR environment, acquired using a smartphone-based 3D reconstruction pipeline. Users can interact using virtual gesture-based tools such as pointers and rulers.
Assessment of radiation awareness training in immersive virtual environments
NASA Astrophysics Data System (ADS)
Whisker, Vaughn E., III
The prospect of new nuclear power plant orders in the near future and the graying of the current workforce create a need to train new personnel faster and better. Immersive virtual reality (VR) may offer a solution to the training challenge. VR technology presented in a CAVE Automatic Virtual Environment (CAVE) provides a high-fidelity, one-to-one scale environment where areas of the power plant can be recreated and virtual radiation environments can be simulated, making it possible to safely expose workers to virtual radiation in the context of the actual work environment. The use of virtual reality for training is supported by many educational theories; constructivism and discovery learning, in particular. Educational theory describes the importance of matching the training to the task. Plant access training and radiation worker training, common forms of training in the nuclear industry, rely on computer-based training methods in most cases, which effectively transfer declarative knowledge, but are poor at transferring skills. If an activity were to be added, the training would provide personnel with the opportunity to develop skills and apply their knowledge so they could be more effective when working in the radiation environment. An experiment was developed to test immersive virtual reality's suitability for training radiation awareness. Using a mixed methodology of quantitative and qualitative measures, the subjects' performances before and after training were assessed. First, subjects completed a pre-test to measure their knowledge prior to completing any training. Next they completed unsupervised computer-based training, which consisted of a PowerPoint presentation and a PDF document. After completing a brief orientation activity in the virtual environment, one group of participants received supplemental radiation awareness training in a simulated radiation environment presented in the CAVE, while a second group, the control group, moved directly to the assessment phase of the experiment. The CAVE supplied an activity-based training environment where learners were able to use a virtual survey meter to explore the properties of radiation sources and the effects of time and distance on radiation exposure. Once the training stage had ended, the subjects completed an assessment activity where they were asked to complete four tasks in a simulated radiation environment in the CAVE, which was designed to provide a more authentic assessment than simply testing understanding using a quiz. After the practicum, the subjects completed a post-test. Survey information was also collected to assist the researcher with interpretation of the collected data. Response to the training was measured by completion time, radiation exposure received, successful completion of the four tasks in the practicum, and scores on the post-test. These results were combined to create a radiation awareness score. In addition, observational data was collected as the subjects completed the tasks. The radiation awareness scores of the control group and the group that received supplemental training in the virtual environment were compared. T-tests showed that the effect of the supplemental training was not significant; however, calculation of the effect size showed a small-to-medium effect of the training. The CAVE group received significantly less radiation exposure during the assessment activity, and they completed the activities on an average of one minute faster. These results indicate that the training was effective, primarily for instilling radiation sensitivity. Observational data collected during the assessment supports this conclusion. The training environment provided by the immersive virtual reality recreated a radiation environment where learners could apply knowledge they had been taught by computer-based training. Activity-based training has been shown to be a more effective way to transfer skills because of the similarity between the training environment and the application environment. Virtual reality enables the training environment to look and feel like the application environment. Because of this, radiation awareness training in an immersive virtual environment should be considered by the nuclear industry, which is supported by the results of this experiment.
ERIC Educational Resources Information Center
Dickey, Michele D.
2005-01-01
Three-dimensional virtual worlds are an emerging medium currently being used in both traditional classrooms and for distance education. Three-dimensional (3D) virtual worlds are a combination of desk-top interactive Virtual Reality within a chat environment. This analysis provides an overview of Active Worlds Educational Universe and Adobe…
VECTR: Virtual Environment Computational Training Resource
NASA Technical Reports Server (NTRS)
Little, William L.
2018-01-01
The Westridge Middle School Curriculum and Community Night is an annual event designed to introduce students and parents to potential employers in the Central Florida area. NASA participated in the event in 2017, and has been asked to come back for the 2018 event on January 25. We will be demonstrating our Microsoft Hololens Virtual Rovers project, and the Virtual Environment Computational Training Resource (VECTR) virtual reality tool.
Virtual acoustic environments for comprehensive evaluation of model-based hearing devices.
Grimm, Giso; Luberadzka, Joanna; Hohmann, Volker
2018-06-01
Create virtual acoustic environments (VAEs) with interactive dynamic rendering for applications in audiology. A toolbox for creation and rendering of dynamic virtual acoustic environments (TASCAR) that allows direct user interaction was developed for application in hearing aid research and audiology. The software architecture and the simulation methods used to produce VAEs are outlined. Example environments are described and analysed. With the proposed software, a tool for simulation of VAEs is available. A set of VAEs rendered with the proposed software was described.
De Leo, Gianluca; Diggs, Leigh A; Radici, Elena; Mastaglio, Thomas W
2014-02-01
Virtual-reality solutions have successfully been used to train distributed teams. This study aimed to investigate the correlation between user characteristics and sense of presence in an online virtual-reality environment where distributed teams are trained. A greater sense of presence has the potential to make training in the virtual environment more effective, leading to the formation of teams that perform better in a real environment. Being able to identify, before starting online training, those user characteristics that are predictors of a greater sense of presence can lead to the selection of trainees who would benefit most from the online simulated training. This is an observational study with a retrospective postsurvey of participants' user characteristics and degree of sense of presence. Twenty-nine members from 3 Air Force National Guard Medical Service expeditionary medical support teams participated in an online virtual environment training exercise and completed the Independent Television Commission-Sense of Presence Inventory survey, which measures sense of presence and user characteristics. Nonparametric statistics were applied to determine the statistical significance of user characteristics to sense of presence. Comparing user characteristics to the 4 scales of the Independent Television Commission-Sense of Presence Inventory using Kendall τ test gave the following results: the user characteristics "how often you play video games" (τ(26)=-0.458, P<0.01) and "television/film production knowledge" (τ(27)=-0.516, P<0.01) were significantly related to negative effects. Negative effects refer to adverse physiologic reactions owing to the virtual environment experience such as dizziness, nausea, headache, and eyestrain. The user characteristic "knowledge of virtual reality" was significantly related to engagement (τ(26)=0.463, P<0.01) and negative effects (τ(26)=-0.404, P<0.05). Individuals who have knowledge about virtual environments and experience with gaming environments report a higher sense of presence that indicates that they will likely benefit more from online virtual training. Future research studies could include a larger population of expeditionary medical support, and the results obtained could be used to create a model that predicts the level of presence based on the user characteristics. To maximize results and minimize costs, only those individuals who, based on their characteristics, are supposed to have a higher sense of presence and less negative effects could be selected for online simulated virtual environment training.
A study on haptic collaborative game in shared virtual environment
NASA Astrophysics Data System (ADS)
Lu, Keke; Liu, Guanyang; Liu, Lingzhi
2013-03-01
A study on collaborative game in shared virtual environment with haptic feedback over computer networks is introduced in this paper. A collaborative task was used where the players located at remote sites and played the game together. The player can feel visual and haptic feedback in virtual environment compared to traditional networked multiplayer games. The experiment was desired in two conditions: visual feedback only and visual-haptic feedback. The goal of the experiment is to assess the impact of force feedback on collaborative task performance. Results indicate that haptic feedback is beneficial for performance enhancement for collaborative game in shared virtual environment. The outcomes of this research can have a powerful impact on the networked computer games.
NASA Technical Reports Server (NTRS)
Hyde, Patricia R.; Loftin, R. Bowen
1993-01-01
These proceedings are organized in the same manner as the conference's contributed sessions, with the papers grouped by topic area. These areas are as follows: VE (virtual environment) training for Space Flight, Virtual Environment Hardware, Knowledge Aquisition for ICAT (Intelligent Computer-Aided Training) & VE, Multimedia in ICAT Systems, VE in Training & Education (1 & 2), Virtual Environment Software (1 & 2), Models in ICAT systems, ICAT Commercial Applications, ICAT Architectures & Authoring Systems, ICAT Education & Medical Applications, Assessing VE for Training, VE & Human Systems (1 & 2), ICAT Theory & Natural Language, ICAT Applications in the Military, VE Applications in Engineering, Knowledge Acquisition for ICAT, and ICAT Applications in Aerospace.
A collaborative molecular modeling environment using a virtual tunneling service.
Lee, Jun; Kim, Jee-In; Kang, Lin-Woo
2012-01-01
Collaborative researches of three-dimensional molecular modeling can be limited by different time zones and locations. A networked virtual environment can be utilized to overcome the problem caused by the temporal and spatial differences. However, traditional approaches did not sufficiently consider integration of different computing environments, which were characterized by types of applications, roles of users, and so on. We propose a collaborative molecular modeling environment to integrate different molecule modeling systems using a virtual tunneling service. We integrated Co-Coot, which is a collaborative crystallographic object-oriented toolkit, with VRMMS, which is a virtual reality molecular modeling system, through a collaborative tunneling system. The proposed system showed reliable quantitative and qualitative results through pilot experiments.
Virtual community centre for power wheelchair training: Experience of children and clinicians.
Torkia, Caryne; Ryan, Stephen E; Reid, Denise; Boissy, Patrick; Lemay, Martin; Routhier, François; Contardo, Resi; Woodhouse, Janet; Archambault, Phillipe S
2017-11-02
To: 1) characterize the overall experience in using the McGill immersive wheelchair - community centre (miWe-CC) simulator; and 2) investigate the experience of presence (i.e., sense of being in the virtual rather than in the real, physical environment) while driving a PW in the miWe-CC. A qualitative research design with structured interviews was used. Fifteen clinicians and 11 children were interviewed after driving a power wheelchair (PW) in the miWe-CC simulator. Data were analyzed using the conventional and directed content analysis approaches. Overall, participants enjoyed using the simulator and experienced a sense of presence in the virtual space. They felt a sense of being in the virtual environment, involved and focused on driving the virtual PW rather than on the surroundings of the actual room where they were. Participants reported several similarities between the virtual community centre layout and activities of the miWe-CC and the day-to-day reality of paediatric PW users. The simulator replicated participants' expectations of real-life PW use and promises to have an effect on improving the driving skills of new PW users. Implications for rehabilitation Among young users, the McGill immersive wheelchair (miWe) simulator provides an experience of presence within the virtual environment. This experience of presence is generated by a sense of being in the virtual scene, a sense of being involved, engaged, and focused on interacting within the virtual environment, and by the perception that the virtual environment is consistent with the real world. The miWe is a relevant and accessible approach, complementary to real world power wheelchair training for young users.
Pain modulation during drives through cold and hot virtual environments.
Mühlberger, Andreas; Wieser, Matthias J; Kenntner-Mabiala, Ramona; Pauli, Paul; Wiederhold, Brenda K
2007-08-01
Evidence exists that virtual worlds reduce pain perception by providing distraction. However, there is no experimental study to show that the type of world used in virtual reality (VR) distraction influences pain perception. Therefore, we investigated whether pain triggered by heat or cold stimuli is modulated by "warm "or "cold " virtual environments and whether virtual worlds reduce pain perception more than does static picture presentation. We expected that cold worlds would reduce pain perception from heat stimuli, while warm environments would reduce pain perception from cold stimuli. Additionally, both virtual worlds should reduce pain perception in general. Heat and cold pain stimuli thresholds were assessed outside VR in 48 volunteers in a balanced crossover design. Participants completed three 4-minute assessment periods: virtual "walks " through (1) a winter and (2) an autumn landscape and static exposure to (3) a neutral landscape. During each period, five heat stimuli or three cold stimuli were delivered via a thermode on the participant's arm, and affective and sensory pain perceptions were rated. Then the thermode was changed to the other arm, and the procedure was repeated with the opposite pain stimuli (heat or cold). We found that both warm and cold virtual environments reduced pain intensity and unpleasantness for heat and cold pain stimuli when compared to the control condition. Since participants wore a head-mounted display (HMD) in both the control condition and VR, we concluded that the distracting value of virtual environments is not explained solely by excluding perception of the real world. Although VR reduced pain unpleasantness, we found no difference in efficacy between the types of virtual world used for each pain stimulus.
Virtual Environments: Issues and Opportunities for Researching Inclusive Educational Practices
NASA Astrophysics Data System (ADS)
Sheehy, Kieron
This chapter argues that virtual environments offer new research areas for those concerned with inclusive education. Further, it proposes that they also present opportunities for developing increasingly inclusive research processes. This chapter considers how researchers might approach researching some of these affordances. It discusses the relationship between specific features of inclusive pedagogy, derived from an international systematic literature review, and the affordances of different forms of virtual characters and environments. Examples are drawn from research in Second LifeTM (SL), virtual tutors and augmented reality. In doing this, the chapter challenges a simplistic notion of isolated physical and virtual worlds and, in the context of inclusion, between the practice of research and the research topic itself. There are a growing number of virtual worlds in which identified educational activities are taking place, or whose activities are being noted for their educational merit. These encompasses non-themed worlds such as SL and Active Worlds, game based worlds such as World of Warcraft and Runescape, and even Club Penguin, a themed virtual where younger players interact through a variety of Penguin themed environments and activities. It has been argued that these spaces, outside traditional education, are able to offer pedagogical insights (Twining 2009) i.e. that these global virtual communities have been identified as being useful as creative educational environments (Delwiche 2006; Sheehy 2009). This chapter will explore how researchers might use these spaces to investigative and create inclusive educational experiences for learners. In order to do this the chapter considers three interrelated issues: What is inclusive education?; How might inclusive education influence virtual world research? And, what might inclusive education look like in virtual worlds?
Virtual Learning Environments.
ERIC Educational Resources Information Center
Follows, Scott B.
1999-01-01
Illustrates the possibilities and educational benefits of virtual learning environments (VLEs), based on experiences with "Thirst for Knowledge," a VLE that simulates the workplace of a major company. While working in this virtual office world, students walk through the building, attend meetings, read reports, receive e-mail, answer the telephone,…
Handbook of Research on Collaborative Teaching Practice in Virtual Learning Environments
ERIC Educational Resources Information Center
Panconesi, Gianni, Ed.; Guida, Maria, Ed.
2017-01-01
Modern technology has enhanced many aspects of life, including classroom education. By offering virtual learning experiences, educational systems can become more efficient and effective at teaching the student population. The "Handbook of Research on Collaborative Teaching Practice in Virtual Learning Environments" highlights program…
Information Seeking in a Virtual Learning Environment.
ERIC Educational Resources Information Center
Byron, Suzanne M.; Young, Jon I.
2000-01-01
Examines the applicability of Kuhlthau's Information Search Process Model in the context of a virtual learning environment at the University of North Texas that used virtual collaborative software. Highlights include cognitive and affective aspects of information seeking; computer experience and confidence; and implications for future research.…
Garretson, Justin R [Albuquerque, NM; Parker, Eric P [Albuquerque, NM; Gladwell, T Scott [Albuquerque, NM; Rigdon, J Brian [Edgewood, NM; Oppel, III, Fred J.
2012-05-29
Apparatus and methods for modifying the operation of a robotic vehicle in a real environment to emulate the operation of the robotic vehicle in a mixed reality environment include a vehicle sensing system having a communications module attached to the robotic vehicle for communicating operating parameters related to the robotic vehicle in a real environment to a simulation controller for simulating the operation of the robotic vehicle in a mixed (live, virtual and constructive) environment wherein the affects of virtual and constructive entities on the operation of the robotic vehicle (and vice versa) are simulated. These effects are communicated to the vehicle sensing system which generates a modified control command for the robotic vehicle including the effects of virtual and constructive entities, causing the robot in the real environment to behave as if virtual and constructive entities existed in the real environment.
Simulation fidelity of a virtual environment display
NASA Technical Reports Server (NTRS)
Nemire, Kenneth; Jacoby, Richard H.; Ellis, Stephen R.
1994-01-01
We assessed the degree to which a virtual environment system produced a faithful simulation of three-dimensional space by investigating the influence of a pitched optic array on the perception of gravity-referenced eye level (GREL). We compared the results with those obtained in a physical environment. In a within-subjects factorial design, 12 subjects indicated GREL while viewing virtual three-dimensional arrays at different static orientations. A physical array biased GREL more than did a geometrically identical virtual pitched array. However, addition of two sets of orthogonal parallel lines (a grid) to the virtual pitched array resulted in as large a bias as that obtained with the physical pitched array. The increased bias was caused by longitudinal, but not the transverse, components of the grid. We discuss implications of our results for spatial orientation models and for designs of virtual displays.
A Stochastic Model of Plausibility in Live Virtual Constructive Environments
2017-09-14
objective in virtual environment research and design is the maintenance of adequate consistency levels in the face of limited system resources such as...provides some commentary with regard to system design considerations and future research directions. II. SYSTEM MODEL DVEs are often designed as a...exceed the system’s requirements. Research into predictive models of virtual environment consistency is needed to provide designers the tools to
ERIC Educational Resources Information Center
deNoyelles, Aimee; Seo, Kay Kyeong-Ju
2012-01-01
A 3D multi-user virtual environment holds promise to support and enhance student online learning communities due to its ability to promote global synchronous interaction and collaboration, rich multisensory experience and expression, and elaborate design capabilities. Second Life[R], a multi-user virtual environment intended for adult users 18 and…
Amato, Mauro; Veglia, Fabrizio; de Faire, Ulf; Giral, Philippe; Rauramaa, Rainer; Smit, Andries J; Kurl, Sudhir; Ravani, Alessio; Frigerio, Beatrice; Sansaro, Daniela; Bonomi, Alice; Tedesco, Calogero C; Castelnuovo, Samuela; Mannarino, Elmo; Humphries, Steve E; Hamsten, Anders; Tremoli, Elena; Baldassarre, Damiano
2017-08-01
Carotid plaque size and the mean common carotid intima-media thickness measured in plaque-free areas (PF CC-IMT mean ) have been identified as predictors of vascular events (VEs), but their complementarity in risk prediction and stratification is still unresolved. The aim of this study was to evaluate the independence of carotid plaque thickness and PF CC-IMT mean in cardiovascular risk prediction and risk stratification. The IMPROVE-study is a European cohort (n = 3703), where the thickness of the largest plaque detected in the whole carotid tree was indexed as cIMT max . PF CC-IMT mean was also assessed. Hazard Ratios (HR) comparing the top quartiles of cIMT max and PF CC-IMT mean versus their respective 1-3 quartiles were calculated using Cox regression. After a 36.2-month follow-up, there were 215 VEs (125 coronary, 73 cerebral and 17 peripheral). Both cIMT max and PF CC-IMT mean were mutually independent predictors of combined-VEs, after adjustment for center, age, sex, risk factors and pharmacological treatment [HR (95% CI) = 1.98 (1.47, 2.67) and 1.68 (1.23, 2.29), respectively]. Both variables were independent predictors of cerebrovascular events (ischemic stroke, transient ischemic attack), while only cIMT max was an independent predictor of coronary events (myocardial infarction, sudden cardiac death, angina pectoris, angioplasty, coronary bypass grafting). In reclassification analyses, PF CC-IMT mean significantly adds to a model including both Framingham Risk Factors and cIMT max (Integrated Discrimination Improvement; IDI = 0.009; p = 0.0001) and vice-versa (IDI = 0.02; p < 0.0001). cIMT max and PF CC-IMT mean are independent predictors of VEs, and as such, they should be used as additive rather than alternative variables in models for cardiovascular risk prediction and reclassification. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.
Characterization of the groundwater aquifers at El Sadat City by joint inversion of VES and TEM data
NASA Astrophysics Data System (ADS)
Massoud, Usama; Kenawy, Abeer A.; Ragab, El-Said A.; Abbas, Abbas M.; El-Kosery, Heba M.
2014-12-01
Vertical Electrical Sounding (VES) and Transient ElectroMagnetic (TEM) survey have been applied for characterizing the groundwater aquifers at El Sadat industrial area. El-Sadat city is one of the most important industrial cities in Egypt. It has been constructed more than three decades ago at about 80 km northwest of Cairo along the Cairo-Alexandria desert road. Groundwater is the main source of water supplies required for domestic, municipal and industrial activities in this area due to the lack of surface water sources. So, it is important to maintain this vital resource in order to sustain the development plans of this city. In this study, VES and TEM data were identically measured at 24 stations along 3 profiles trending NE-SW with the elongation of the study area. The measuring points were arranged in a grid-like pattern with both inter-station spacing and line-line distance of about 2 km. After performing the necessary processing steps, the VES and TEM data sets were inverted individually to multi-layer models, followed by a joint inversion of both data sets. Joint inversion process has succeeded to overcome the model-equivalence problem encountered in the inversion of individual data set. Then, the joint models were used for the construction of a number of cross sections and contour maps showing the lateral and vertical distribution of the geoelectrical parameters in the subsurface medium. Interpretation of the obtained results and correlation with the available geological and hydrogeological information revealed TWO aquifer systems in the area. The shallow Pleistocene aquifer consists of sand and gravel saturated with fresh water and exhibits large thickness exceeding 200 m. The deep Pliocene aquifer is composed of clay and sand and shows low resistivity values. The water-bearing layer of the Pleistocene aquifer and the upper surface of Pliocene aquifer are continuous and no structural features have cut this continuity through the investigated area.
Sorensen, Mads Solvsten; Mosegaard, Jesper; Trier, Peter
2009-06-01
Existing virtual simulators for middle ear surgery are based on 3-dimensional (3D) models from computed tomographic or magnetic resonance imaging data in which image quality is limited by the lack of detail (maximum, approximately 50 voxels/mm3), natural color, and texture of the source material.Virtual training often requires the purchase of a program, a customized computer, and expensive peripherals dedicated exclusively to this purpose. The Visible Ear freeware library of digital images from a fresh-frozen human temporal bone was segmented, and real-time volume rendered as a 3D model of high-fidelity, true color, and great anatomic detail and realism of the surgically relevant structures. A haptic drilling model was developed for surgical interaction with the 3D model. Realistic visualization in high-fidelity (approximately 125 voxels/mm3) and true color, 2D, or optional anaglyph stereoscopic 3D was achieved on a standard Core 2 Duo personal computer with a GeForce 8,800 GTX graphics card, and surgical interaction was provided through a relatively inexpensive (approximately $2,500) Phantom Omni haptic 3D pointing device. This prototype is published for download (approximately 120 MB) as freeware at http://www.alexandra.dk/ves/index.htm.With increasing personal computer performance, future versions may include enhanced resolution (up to 8,000 voxels/mm3) and realistic interaction with deformable soft tissue components such as skin, tympanic membrane, dura, and cholesteatomas-features some of which are not possible with computed tomographic-/magnetic resonance imaging-based systems.
Sense of presence and anxiety during virtual social interactions between a human and virtual humans.
Morina, Nexhmedin; Brinkman, Willem-Paul; Hartanto, Dwi; Emmelkamp, Paul M G
2014-01-01
Virtual reality exposure therapy (VRET) has been shown to be effective in treatment of anxiety disorders. Yet, there is lack of research on the extent to which interaction between the individual and virtual humans can be successfully implanted to increase levels of anxiety for therapeutic purposes. This proof-of-concept pilot study aimed at examining levels of the sense of presence and anxiety during exposure to virtual environments involving social interaction with virtual humans and using different virtual reality displays. A non-clinical sample of 38 participants was randomly assigned to either a head-mounted display (HMD) with motion tracker and sterescopic view condition or a one-screen projection-based virtual reality display condition. Participants in both conditions engaged in free speech dialogues with virtual humans controlled by research assistants. It was hypothesized that exposure to virtual social interactions will elicit moderate levels of sense of presence and anxiety in both groups. Further it was expected that participants in the HMD condition will report higher scores of sense of presence and anxiety than participants in the one-screen projection-based display condition. Results revealed that in both conditions virtual social interactions were associated with moderate levels of sense of presence and anxiety. Additionally, participants in the HMD condition reported significantly higher levels of presence than those in the one-screen projection-based display condition (p = .001). However, contrary to the expectations neither the average level of anxiety nor the highest level of anxiety during exposure to social virtual environments differed between the groups (p = .97 and p = .75, respectively). The findings suggest that virtual social interactions can be successfully applied in VRET to enhance sense of presence and anxiety. Furthermore, our results indicate that one-screen projection-based displays can successfully activate levels of anxiety in social virtual environments. The outcome can prove helpful in using low-cost projection-based virtual reality environments for treating individuals with social phobia.
The virtual windtunnel: Visualizing modern CFD datasets with a virtual environment
NASA Technical Reports Server (NTRS)
Bryson, Steve
1993-01-01
This paper describes work in progress on a virtual environment designed for the visualization of pre-computed fluid flows. The overall problems involved in the visualization of fluid flow are summarized, including computational, data management, and interface issues. Requirements for a flow visualization are summarized. Many aspects of the implementation of the virtual windtunnel were uniquely determined by these requirements. The user interface is described in detail.
Current limitations into the application of virtual reality to mental health research.
Huang, M P; Alessi, N E
1998-01-01
Virtual Reality (VR) environments have significant potential as a tool in mental health research, but are limited by technical factors and by mental health research factors. Technical difficulties include cost and complexity of virtual environment creation. Mental health research difficulties include current inadequacy of standards to specify needed details for virtual environment design. Technical difficulties are disappearing with technological advances, but the mental health research difficulties will take a concerted effort to overcome. Some of this effort will need to be directed at the formation of collaborative projects and standards for how such collaborations should proceed.
Virtual Learning: Possibilities and Realization
ERIC Educational Resources Information Center
Kerimbayev, Nurassyl
2016-01-01
In the article it was important to consider two basic moments i.e., impact mode of using virtual environment at training process within one faculty of the University, directly at training quality and what outcomes can be reached therewith. The work significance consists of studying the virtual environment effect instead of traditional educational…
Large-Scale Networked Virtual Environments: Architecture and Applications
ERIC Educational Resources Information Center
Lamotte, Wim; Quax, Peter; Flerackers, Eddy
2008-01-01
Purpose: Scalability is an important research topic in the context of networked virtual environments (NVEs). This paper aims to describe the ALVIC (Architecture for Large-scale Virtual Interactive Communities) approach to NVE scalability. Design/methodology/approach: The setup and results from two case studies are shown: a 3-D learning environment…
Designing a Virtual-Reality-Based, Gamelike Math Learning Environment
ERIC Educational Resources Information Center
Xu, Xinhao; Ke, Fengfeng
2016-01-01
This exploratory study examined the design issues related to a virtual-reality-based, gamelike learning environment (VRGLE) developed via OpenSimulator, an open-source virtual reality server. The researchers collected qualitative data to examine the VRGLE's usability, playability, and content integration for math learning. They found it important…
Virtual Reality and Special Needs
ERIC Educational Resources Information Center
Jeffs, Tara L.
2009-01-01
The use of virtual environments for special needs is as diverse as the field of Special Education itself and the individuals it serves. Individuals with special needs often face challenges with attention, language, spatial abilities, memory, higher reasoning and knowledge acquisition. Research in the use of Virtual Learning Environments (VLE)…
Pedagogical Intercultural Practice of Teachers in Virtual Environments
ERIC Educational Resources Information Center
Barreto, Carmen Ricardo; Haydar, Jorge Mizzuno
2016-01-01
This study presents some of the results of the project "Training and Development of Intercultural Competency of Teachers in Virtual Environments", carried out in ten Colombian Caribbean higher education institutions (HEI) offering virtual programs. It was performed in three steps: 1-diagnosis, 2-training, and 3-analysis of the…
Meal-Maker: A Virtual Meal Preparation Environment for Children with Cerebral Palsy
ERIC Educational Resources Information Center
Kirshner, Sharon; Weiss, Patrice L.; Tirosh, Emanuel
2011-01-01
Virtual reality (VR) technology enables evaluation and practice of specific skills in a motivating, user-friendly and safe way. The implementation of virtual game environments within clinical settings has increased substantially in recent years. However, the psychometric properties and feasibility of many applications have not been fully…
Two-photon calcium imaging in mice navigating a virtual reality environment.
Leinweber, Marcus; Zmarz, Pawel; Buchmann, Peter; Argast, Paul; Hübener, Mark; Bonhoeffer, Tobias; Keller, Georg B
2014-02-20
In recent years, two-photon imaging has become an invaluable tool in neuroscience, as it allows for chronic measurement of the activity of genetically identified cells during behavior(1-6). Here we describe methods to perform two-photon imaging in mouse cortex while the animal navigates a virtual reality environment. We focus on the aspects of the experimental procedures that are key to imaging in a behaving animal in a brightly lit virtual environment. The key problems that arise in this experimental setup that we here address are: minimizing brain motion related artifacts, minimizing light leak from the virtual reality projection system, and minimizing laser induced tissue damage. We also provide sample software to control the virtual reality environment and to do pupil tracking. With these procedures and resources it should be possible to convert a conventional two-photon microscope for use in behaving mice.
Sounds of silence: How to animate virtual worlds with sound
NASA Technical Reports Server (NTRS)
Astheimer, Peter
1993-01-01
Sounds are an integral and sometimes annoying part of our daily life. Virtual worlds which imitate natural environments gain a lot of authenticity from fast, high quality visualization combined with sound effects. Sounds help to increase the degree of immersion for human dwellers in imaginary worlds significantly. The virtual reality toolkit of IGD (Institute for Computer Graphics) features a broad range of standard visual and advanced real-time audio components which interpret an object-oriented definition of the scene. The virtual reality system 'Virtual Design' realized with the toolkit enables the designer of virtual worlds to create a true audiovisual environment. Several examples on video demonstrate the usage of the audio features in Virtual Design.
A MOO-Based Virtual Training Environment.
ERIC Educational Resources Information Center
Mateas, Michael; Lewis, Scott
1996-01-01
Describes the implementation of a virtual environment to support the training of engineers in Panels of Experts (POE), a vehicle for gathering customer data. Describes the environment, discusses some issues of communication and interaction raised by the technology, and relays the experiences of new users within this environment. (RS)
Virtual Environments in Biology Teaching
ERIC Educational Resources Information Center
Mikropoulos, Tassos A.; Katsikis, Apostolos; Nikolou, Eugenia; Tsakalis, Panayiotis
2003-01-01
This article reports on the design, development and evaluation of an educational virtual environment for biology teaching. In particular it proposes a highly interactive three-dimensional synthetic environment involving certain learning tasks for the support of teaching plant cell biology and the process of photosynthesis. The environment has been…
Lahav, Orly; Schloerb, David W.; Srinivasan, Mandayam A.
2014-01-01
This paper presents the integration of a virtual environment (BlindAid) in an orientation and mobility rehabilitation program as a training aid for people who are blind. BlindAid allows the users to interact with different virtual structures and objects through auditory and haptic feedback. This research explores if and how use of the BlindAid in conjunction with a rehabilitation program can help people who are blind train themselves in familiar and unfamiliar spaces. The study, focused on nine participants who were congenitally, adventitiously, and newly blind, during their orientation and mobility rehabilitation program at the Carroll Center for the Blind (Newton, Massachusetts, USA). The research was implemented using virtual environment (VE) exploration tasks and orientation tasks in virtual environments and real spaces. The methodology encompassed both qualitative and quantitative methods, including interviews, a questionnaire, videotape recording, and user computer logs. The results demonstrated that the BlindAid training gave participants additional time to explore the virtual environment systematically. Secondly, it helped elucidate several issues concerning the potential strengths of the BlindAid system as a training aid for orientation and mobility for both adults and teenagers who are congenitally, adventitiously, and newly blind. PMID:25284952
LVC interaction within a mixed-reality training system
NASA Astrophysics Data System (ADS)
Pollock, Brice; Winer, Eliot; Gilbert, Stephen; de la Cruz, Julio
2012-03-01
The United States military is increasingly pursuing advanced live, virtual, and constructive (LVC) training systems for reduced cost, greater training flexibility, and decreased training times. Combining the advantages of realistic training environments and virtual worlds, mixed reality LVC training systems can enable live and virtual trainee interaction as if co-located. However, LVC interaction in these systems often requires constructing immersive environments, developing hardware for live-virtual interaction, tracking in occluded environments, and an architecture that supports real-time transfer of entity information across many systems. This paper discusses a system that overcomes these challenges to empower LVC interaction in a reconfigurable, mixed reality environment. This system was developed and tested in an immersive, reconfigurable, and mixed reality LVC training system for the dismounted warfighter at ISU, known as the Veldt, to overcome LVC interaction challenges and as a test bed for cuttingedge technology to meet future U.S. Army battlefield requirements. Trainees interact physically in the Veldt and virtually through commercial and developed game engines. Evaluation involving military trained personnel found this system to be effective, immersive, and useful for developing the critical decision-making skills necessary for the battlefield. Procedural terrain modeling, model-matching database techniques, and a central communication server process all live and virtual entity data from system components to create a cohesive virtual world across all distributed simulators and game engines in real-time. This system achieves rare LVC interaction within multiple physical and virtual immersive environments for training in real-time across many distributed systems.
Constraint, Intelligence, and Control Hierarchy in Virtual Environments. Chapter 1
NASA Technical Reports Server (NTRS)
Sheridan, Thomas B.
2007-01-01
This paper seeks to deal directly with the question of what makes virtual actors and objects that are experienced in virtual environments seem real. (The term virtual reality, while more common in public usage, is an oxymoron; therefore virtual environment is the preferred term in this paper). Reality is difficult topic, treated for centuries in those sub-fields of philosophy called ontology- "of or relating to being or existence" and epistemology- "the study of the method and grounds of knowledge, especially with reference to its limits and validity" (both from Webster s, 1965). Advances in recent decades in the technologies of computers, sensors and graphics software have permitted human users to feel present or experience immersion in computer-generated virtual environments. This has motivated a keen interest in probing this phenomenon of presence and immersion not only philosophically but also psychologically and physiologically in terms of the parameters of the senses and sensory stimulation that correlate with the experience (Ellis, 1991). The pages of the journal Presence: Teleoperators and Virtual Environments have seen much discussion of what makes virtual environments seem real (see, e.g., Slater, 1999; Slater et al. 1994; Sheridan, 1992, 2000). Stephen Ellis, when organizing the meeting that motivated this paper, suggested to invited authors that "We may adopt as an organizing principle for the meeting that the genesis of apparently intelligent interaction arises from an upwelling of constraints determined by a hierarchy of lower levels of behavioral interaction. "My first reaction was "huh?" and my second was "yeah, that seems to make sense." Accordingly the paper seeks to explain from the author s viewpoint, why Ellis s hypothesis makes sense. What is the connection of "presence" or "immersion" of an observer in a virtual environment, to "constraints" and what types of constraints. What of "intelligent interaction," and is it the intelligence of the observer or the intelligence of the environment (whatever the latter may mean) that is salient? And finally, what might be relevant about "upwelling" of constraints as determined by a hierarchy of levels of interaction?
de Bruin, E D; Schoene, D; Pichierri, G; Smith, S T
2010-08-01
Virtual augmented exercise, an emerging technology that can help to promote physical activity and combine the strengths of indoor and outdoor exercise, has recently been proposed as having the potential to increase exercise behavior in older adults. By creating a strong presence in a virtual, interactive environment, distraction can be taken to greater levels while maintaining the benefits of indoor exercises which may result in a shift from negative to positive thoughts about exercise. Recent findings on young participants show that virtual reality training enhances mood, thus, increasing enjoyment and energy. For older adults virtual, interactive environments can influence postural control and fall events by stimulating the sensory cues that are responsible in maintaining balance and orientation. However, the potential of virtual reality training has yet to be explored for older adults. This manuscript describes the potential of dance pad training protocols in the elderly and reports on the theoretical rationale of combining physical game-like exercises with sensory and cognitive challenges in a virtual environment.
Command & Control in Virtual Environments: Designing a Virtual Environment for Experimentation
2010-06-01
proceed with the research: Second Life/ OpenSim A popular leader in the desktop virtual worlds revolution, for many Second Life has become...prototype environments and adapt them quickly within the world. OpenSim is an open-source community built around upon the Second Life platform...functionality natively present in Second Life and the Opensim platform. With the recent release of Second Life Viewer 2.0, which contains a complete
NASA Technical Reports Server (NTRS)
Hyde, Patricia R.; Loftin, R. Bowen
1993-01-01
The volume 2 proceedings from the 1993 Conference on Intelligent Computer-Aided Training and Virtual Environment Technology are presented. Topics discussed include intelligent computer assisted training (ICAT) systems architectures, ICAT educational and medical applications, virtual environment (VE) training and assessment, human factors engineering and VE, ICAT theory and natural language processing, ICAT military applications, VE engineering applications, ICAT knowledge acquisition processes and applications, and ICAT aerospace applications.
ERIC Educational Resources Information Center
Ageel, Mohammed
2012-01-01
The adoption of ICT-enabled teaching in contemporary schools has largely lagged behind despite its obvious and many benefits, mainly because teachers still hold ignorant, misinformed and highly negative attitudes towards ICT-enabled teaching. This article aimed at investigating the effect of Virtual Learning Environments (VLE) on university…
A Collaborative Molecular Modeling Environment Using a Virtual Tunneling Service
Lee, Jun; Kim, Jee-In; Kang, Lin-Woo
2012-01-01
Collaborative researches of three-dimensional molecular modeling can be limited by different time zones and locations. A networked virtual environment can be utilized to overcome the problem caused by the temporal and spatial differences. However, traditional approaches did not sufficiently consider integration of different computing environments, which were characterized by types of applications, roles of users, and so on. We propose a collaborative molecular modeling environment to integrate different molecule modeling systems using a virtual tunneling service. We integrated Co-Coot, which is a collaborative crystallographic object-oriented toolkit, with VRMMS, which is a virtual reality molecular modeling system, through a collaborative tunneling system. The proposed system showed reliable quantitative and qualitative results through pilot experiments. PMID:22927721
Consistency of performance of robot-assisted surgical tasks in virtual reality.
Suh, I H; Siu, K-C; Mukherjee, M; Monk, E; Oleynikov, D; Stergiou, N
2009-01-01
The purpose of this study was to investigate consistency of performance of robot-assisted surgical tasks in a virtual reality environment. Eight subjects performed two surgical tasks, bimanual carrying and needle passing, with both the da Vinci surgical robot and a virtual reality equivalent environment. Nonlinear analysis was utilized to evaluate consistency of performance by calculating the regularity and the amount of divergence in the movement trajectories of the surgical instrument tips. Our results revealed that movement patterns for both training tasks were statistically similar between the two environments. Consistency of performance as measured by nonlinear analysis could be an appropriate methodology to evaluate the complexity of the training tasks between actual and virtual environments and assist in developing better surgical training programs.
NASA Astrophysics Data System (ADS)
Beckhaus, Steffi
Virtual Reality aims at creating an artificial environment that can be perceived as a substitute to a real setting. Much effort in research and development goes into the creation of virtual environments that in their majority are perceivable only by eyes and hands. The multisensory nature of our perception, however, allows and, arguably, also expects more than that. As long as we are not able to simulate and deliver a fully sensory believable virtual environment to a user, we could make use of the fully sensory, multi-modal nature of real objects to fill in for this deficiency. The idea is to purposefully integrate real artifacts into the application and interaction, instead of dismissing anything real as hindering the virtual experience. The term virtual reality - denoting the goal, not the technology - shifts from a core virtual reality to an “enriched” reality, technologically encompassing both the computer generated and the real, physical artifacts. Together, either simultaneously or in a hybrid way, real and virtual jointly provide stimuli that are perceived by users through their senses and are later formed into an experience by the user's mind.
NASA Technical Reports Server (NTRS)
Twombly, I. Alexander; Smith, Jeffrey; Bruyns, Cynthia; Montgomery, Kevin; Boyle, Richard
2003-01-01
The International Space Station will soon provide an unparalleled research facility for studying the near- and longer-term effects of microgravity on living systems. Using the Space Station Glovebox Facility - a compact, fully contained reach-in environment - astronauts will conduct technically challenging life sciences experiments. Virtual environment technologies are being developed at NASA Ames Research Center to help realize the scientific potential of this unique resource by facilitating the experimental hardware and protocol designs and by assisting the astronauts in training. The Virtual GloveboX (VGX) integrates high-fidelity graphics, force-feedback devices and real- time computer simulation engines to achieve an immersive training environment. Here, we describe the prototype VGX system, the distributed processing architecture used in the simulation environment, and modifications to the visualization pipeline required to accommodate the display configuration.
Gallagher, Rosemary; Damodaran, Harish; Werner, William G; Powell, Wendy; Deutsch, Judith E
2016-08-19
Evidence based virtual environments (VEs) that incorporate compensatory strategies such as cueing may change motor behavior and increase exercise intensity while also being engaging and motivating. The purpose of this study was to determine if persons with Parkinson's disease and aged matched healthy adults responded to auditory and visual cueing embedded in a bicycling VE as a method to increase exercise intensity. We tested two groups of participants, persons with Parkinson's disease (PD) (n = 15) and age-matched healthy adults (n = 13) as they cycled on a stationary bicycle while interacting with a VE. Participants cycled under two conditions: auditory cueing (provided by a metronome) and visual cueing (represented as central road markers in the VE). The auditory condition had four trials in which auditory cues or the VE were presented alone or in combination. The visual condition had five trials in which the VE and visual cue rate presentation was manipulated. Data were analyzed by condition using factorial RMANOVAs with planned t-tests corrected for multiple comparisons. There were no differences in pedaling rates between groups for both the auditory and visual cueing conditions. Persons with PD increased their pedaling rate in the auditory (F 4.78, p = 0.029) and visual cueing (F 26.48, p < 0.000) conditions. Age-matched healthy adults also increased their pedaling rate in the auditory (F = 24.72, p < 0.000) and visual cueing (F = 40.69, p < 0.000) conditions. Trial-to-trial comparisons in the visual condition in age-matched healthy adults showed a step-wise increase in pedaling rate (p = 0.003 to p < 0.000). In contrast, persons with PD increased their pedaling rate only when explicitly instructed to attend to the visual cues (p < 0.000). An evidenced based cycling VE can modify pedaling rate in persons with PD and age-matched healthy adults. Persons with PD required attention directed to the visual cues in order to obtain an increase in cycling intensity. The combination of the VE and auditory cues was neither additive nor interfering. These data serve as preliminary evidence that embedding auditory and visual cues to alter cycling speed in a VE as method to increase exercise intensity that may promote fitness.
A specification of 3D manipulation in virtual environments
NASA Technical Reports Server (NTRS)
Su, S. Augustine; Furuta, Richard
1994-01-01
In this paper we discuss the modeling of three basic kinds of 3-D manipulations in the context of a logical hand device and our virtual panel architecture. The logical hand device is a useful software abstraction representing hands in virtual environments. The virtual panel architecture is the 3-D component of the 2-D window systems. Both of the abstractions are intended to form the foundation for adaptable 3-D manipulation.
ERIC Educational Resources Information Center
Salinas Vacca, Yakelin
2014-01-01
This paper reports on an exploratory, descriptive, and interpretive study in which the roles of discussion boards, the students, the teacher, and the monitors were explored as they constructed a collaborative class project in a virtual environment. This research was conducted in the virtual program of a Colombian public university. Data were…
Annerstedt, Matilda; Jönsson, Peter; Wallergård, Mattias; Johansson, Gerd; Karlson, Björn; Grahn, Patrik; Hansen, Ase Marie; Währborg, Peter
2013-06-13
Experimental research on stress recovery in natural environments is limited, as is study of the effect of sounds of nature. After inducing stress by means of a virtual stress test, we explored physiological recovery in two different virtual natural environments (with and without exposure to sounds of nature) and in one control condition. Cardiovascular data and saliva cortisol were collected. Repeated ANOVA measurements indicated parasympathetic activation in the group subjected to sounds of nature in a virtual natural environment, suggesting enhanced stress recovery may occur in such surroundings. The group that recovered in virtual nature without sound and the control group displayed no particular autonomic activation or deactivation. The results demonstrate a potential mechanistic link between nature, the sounds of nature, and stress recovery, and suggest the potential importance of virtual reality as a tool in this research field. Copyright © 2013 Elsevier Inc. All rights reserved.
A fast simulation method for radiation maps using interpolation in a virtual environment.
Li, Meng-Kun; Liu, Yong-Kuo; Peng, Min-Jun; Xie, Chun-Li; Yang, Li-Qun
2018-05-10
In nuclear decommissioning, virtual simulation technology is a useful tool to achieve an effective work process by using virtual environments to represent the physical and logical scheme of a real decommissioning project. This technology is cost-saving and time-saving, with the capacity to develop various decommissioning scenarios and reduce the risk of retrofitting. The method utilises a radiation map in a virtual simulation as the basis for the assessment of exposure to a virtual human. In this paper, we propose a fast simulation method using a known radiation source. The method has a unique advantage over point kernel and Monte Carlo methods because it generates the radiation map using interpolation in a virtual environment. The simulation of the radiation map including the calculation and the visualisation were realised using UNITY and MATLAB. The feasibility of the proposed method was tested on a hypothetical case and the results obtained are discussed in this paper.
Declarative Knowledge Acquisition in Immersive Virtual Learning Environments
ERIC Educational Resources Information Center
Webster, Rustin
2016-01-01
The author investigated the interaction effect of immersive virtual reality (VR) in the classroom. The objective of the project was to develop and provide a low-cost, scalable, and portable VR system containing purposely designed and developed immersive virtual learning environments for the US Army. The purpose of the mixed design experiment was…
ERIC Educational Resources Information Center
Richardson, April; Hazzard, Matthew; Challman, Sandra D.; Morgenstein, Aaron M.; Brueckner, Jennifer K.
2011-01-01
This article describes the emerging role of educational multiuser virtual environments, specifically Second Life[TM], in anatomical sciences education. Virtual worlds promote inquiry-based learning and conceptual understanding, potentially making them applicable for teaching and learning gross anatomy. A short introduction to Second Life as an…
A Test of Spatial Contiguity for Virtual Human's Gestures in Multimedia Learning Environments
ERIC Educational Resources Information Center
Craig, Scotty D.; Twyford, Jessica; Irigoyen, Norma; Zipp, Sarah A.
2015-01-01
Virtual humans are becoming an easily available and popular component of multimedia learning that are often used in online learning environments. There is still a need for systematic research into their effectiveness. The current study investigates the positioning of a virtual human's gestures when guiding the learner through a multimedia…
ERIC Educational Resources Information Center
Triggs, Riley; Jarmon, Leslie; Villareal, Tracy A.
2010-01-01
Virtual environments can resolve many practical and pedagogical challenges within higher education. Economic considerations, accessibility issues, and safety concerns can all be somewhat alleviated by creating learning activities in a virtual space. Because of the removal of real-world physical limitations like gravity, durability and scope,…
Spatial Integration under Contextual Control in a Virtual Environment
ERIC Educational Resources Information Center
Molet, Mikael; Gambet, Boris; Bugallo, Mehdi; Miller, Ralph R.
2012-01-01
The role of context was examined in the selection and integration of independently learned spatial relationships. Using a dynamic 3D virtual environment, participants learned one spatial relationship between landmarks A and B which was established in one virtual context (e.g., A is left of B) and a different spatial relationship which was…
Active Learning through the Use of Virtual Environments
ERIC Educational Resources Information Center
Mayrose, James
2012-01-01
Immersive Virtual Reality (VR) has seen explosive growth over the last decade. Immersive VR attempts to give users the sensation of being fully immersed in a synthetic environment by providing them with 3D hardware, and allowing them to interact with objects in virtual worlds. The technology is extremely effective for learning and exploration, and…
A Virtual World Workshop Environment for Learning Agile Software Development Techniques
ERIC Educational Resources Information Center
Parsons, David; Stockdale, Rosemary
2012-01-01
Multi-User Virtual Environments (MUVEs) are the subject of increasing interest for educators and trainers. This article reports on a longitudinal project that seeks to establish a virtual agile software development workshop hosted in the Open Wonderland MUVE, designed to help learners to understand the basic principles of some core agile software…
ERIC Educational Resources Information Center
Patera, Marianne; Draper, Steve; Naef, Martin
2008-01-01
This paper presents an exploratory study that created a virtual reality environment (VRE) to stimulate motivation and creativity in imaginative writing at primary school level. The main aim of the study was to investigate if an interactive, semi-immersive virtual reality world could increase motivation and stimulate pupils' imagination in the…
Pre-Service Teachers Designing Virtual World Learning Environments
ERIC Educational Resources Information Center
Jacka, Lisa; Booth, Kate
2012-01-01
Integrating Information Technology Communications in the classroom has been an important part of pre-service teacher education for over a decade. The advent of virtual worlds provides the pre-service teacher with an opportunity to study teaching and learning in a highly immersive 3D computer-based environment. Virtual worlds also provide a place…
Impact of Virtual Work Environment on Traditional Team Domains.
ERIC Educational Resources Information Center
Geroy, Gary D.; Olson, Joel; Hartman, Jackie
2002-01-01
Examines a virtual work team to determine the domains of the team and the effect the virtual work environment had on the domains. Discusses results of a literature review and a phenomenological heuristic case study, including the effects of post-modern philosophy and postindustrial society on changes in the marketplace. (Contains 79 references.)…
Walk, Fly, or Teleport to Learning: Virtual Worlds in the Classroom
ERIC Educational Resources Information Center
Yoder, Maureen Brown
2009-01-01
For educators looking for new ways to engage their students, multiuser virtual environments (MUVEs) offer a great opportunity for creative teaching and learning. MUVEs teach students social, technical, and practical life skills in a setting that is engaging and playful. One might be surprised how much these virtual environments teach students…
Virtual reality and physical rehabilitation: a new toy or a new research and rehabilitation tool?
Keshner, Emily A
2004-01-01
Virtual reality (VR) technology is rapidly becoming a popular application for physical rehabilitation and motor control research. But questions remain about whether this technology really extends our ability to influence the nervous system or whether moving within a virtual environment just motivates the individual to perform. I served as guest editor of this month's issue of the Journal of NeuroEngineering and Rehabilitation (JNER) for a group of papers on augmented and virtual reality in rehabilitation. These papers demonstrate a variety of approaches taken for applying VR technology to physical rehabilitation. The papers by Kenyon et al. and Sparto et al. address critical questions about how this technology can be applied to physical rehabilitation and research. The papers by Sveistrup and Viau et al. explore whether action within a virtual environment is equivalent to motor performance within the physical environment. Finally, papers by Riva et al. and Weiss et al. discuss the important characteristics of a virtual environment that will be most effective for obtaining changes in the motor system. PMID:15679943
Using SecondLife Online Virtual World Technology to Introduce Educators to the Digital Culture
NASA Technical Reports Server (NTRS)
Jamison, John
2008-01-01
The rapidly changing culture resulting from new technologies and digital gaming has created an increasing language gap between traditional educators and today's learners (Natkin, 2006; Seely-Brown, 2000). This study seeks to use the online virtual world of SecondLife.com as a tool to introduce educators to this new environment for learning. This study observes the activities and perceptions of a group of educators given unscripted access to this virtual environment. The results 'suggest that although serious technology limitations do currently exist, the potential of this virtual world environment as a learning experience for educators is strong.
Enhancing Security by System-Level Virtualization in Cloud Computing Environments
NASA Astrophysics Data System (ADS)
Sun, Dawei; Chang, Guiran; Tan, Chunguang; Wang, Xingwei
Many trends are opening up the era of cloud computing, which will reshape the IT industry. Virtualization techniques have become an indispensable ingredient for almost all cloud computing system. By the virtual environments, cloud provider is able to run varieties of operating systems as needed by each cloud user. Virtualization can improve reliability, security, and availability of applications by using consolidation, isolation, and fault tolerance. In addition, it is possible to balance the workloads by using live migration techniques. In this paper, the definition of cloud computing is given; and then the service and deployment models are introduced. An analysis of security issues and challenges in implementation of cloud computing is identified. Moreover, a system-level virtualization case is established to enhance the security of cloud computing environments.
Guidelines for developing distributed virtual environment applications
NASA Astrophysics Data System (ADS)
Stytz, Martin R.; Banks, Sheila B.
1998-08-01
We have conducted a variety of projects that served to investigate the limits of virtual environments and distributed virtual environment (DVE) technology for the military and medical professions. The projects include an application that allows the user to interactively explore a high-fidelity, dynamic scale model of the Solar System and a high-fidelity, photorealistic, rapidly reconfigurable aircraft simulator. Additional projects are a project for observing, analyzing, and understanding the activity in a military distributed virtual environment, a project to develop a distributed threat simulator for training Air Force pilots, a virtual spaceplane to determine user interface requirements for a planned military spaceplane system, and an automated wingman for use in supplementing or replacing human-controlled systems in a DVE. The last two projects are a virtual environment user interface framework; and a project for training hospital emergency department personnel. In the process of designing and assembling the DVE applications in support of these projects, we have developed rules of thumb and insights into assembling DVE applications and the environment itself. In this paper, we open with a brief review of the applications that were the source for our insights and then present the lessons learned as a result of these projects. The lessons we have learned fall primarily into five areas. These areas are requirements development, software architecture, human-computer interaction, graphical database modeling, and construction of computer-generated forces.
Visual landmarks facilitate rodent spatial navigation in virtual reality environments
Youngstrom, Isaac A.; Strowbridge, Ben W.
2012-01-01
Because many different sensory modalities contribute to spatial learning in rodents, it has been difficult to determine whether spatial navigation can be guided solely by visual cues. Rodents moving within physical environments with visual cues engage a variety of nonvisual sensory systems that cannot be easily inhibited without lesioning brain areas. Virtual reality offers a unique approach to ask whether visual landmark cues alone are sufficient to improve performance in a spatial task. We found that mice could learn to navigate between two water reward locations along a virtual bidirectional linear track using a spherical treadmill. Mice exposed to a virtual environment with vivid visual cues rendered on a single monitor increased their performance over a 3-d training regimen. Training significantly increased the percentage of time avatars controlled by the mice spent near reward locations in probe trials without water rewards. Neither improvement during training or spatial learning for reward locations occurred with mice operating a virtual environment without vivid landmarks or with mice deprived of all visual feedback. Mice operating the vivid environment developed stereotyped avatar turning behaviors when alternating between reward zones that were positively correlated with their performance on the probe trial. These results suggest that mice are able to learn to navigate to specific locations using only visual cues presented within a virtual environment rendered on a single computer monitor. PMID:22345484
Christie, Lorna S.; Goossens, Richard H. M.; de Ridder, Huib; Jakimowicz, Jack J.
2010-01-01
Background The aim of this study is to investigate the influence of the presence of anatomic landmarks on the performance of angled laparoscope navigation on the SimSurgery SEP simulator. Methods Twenty-eight experienced laparoscopic surgeons (familiar with 30° angled laparoscope, >100 basic laparoscopic procedures, >5 advanced laparoscopic procedures) and 23 novices (no laparoscopy experience) performed the Camera Navigation task in an abstract virtual environment (CN-box) and in a virtual representation of the lower abdomen (CN-abdomen). They also rated the realism and added value of the virtual environments on seven-point scales. Results Within both groups, the CN-box task was accomplished in less time and with shorter tip trajectory than the CN-abdomen task (Wilcoxon test, p < 0.05). No significant differences were found between the performances of the experienced participants and the novices on the CN tasks (Mann–Whitney U test, p > 0.05). In both groups, the CN tasks were perceived as hard work and more challenging than anticipated. Conclusions Performance of the angled laparoscope navigation task is influenced by the virtual environment surrounding the exercise. The task was performed better in an abstract environment than in a virtual environment with anatomic landmarks. More insight is required into the influence and function of different types of intrinsic and extrinsic feedback on the effectiveness of preclinical simulator training. PMID:20419318
Suma, Evan A; Lipps, Zachary; Finkelstein, Samantha; Krum, David M; Bolas, Mark
2012-04-01
Walking is only possible within immersive virtual environments that fit inside the boundaries of the user's physical workspace. To reduce the severity of the restrictions imposed by limited physical area, we introduce "impossible spaces," a new design mechanic for virtual environments that wish to maximize the size of the virtual environment that can be explored with natural locomotion. Such environments make use of self-overlapping architectural layouts, effectively compressing comparatively large interior environments into smaller physical areas. We conducted two formal user studies to explore the perception and experience of impossible spaces. In the first experiment, we showed that reasonably small virtual rooms may overlap by as much as 56% before users begin to detect that they are in an impossible space, and that the larger virtual rooms that expanded to maximally fill our available 9.14 m x 9.14 m workspace may overlap by up to 31%. Our results also demonstrate that users perceive distances to objects in adjacent overlapping rooms as if the overall space was uncompressed, even at overlap levels that were overtly noticeable. In our second experiment, we combined several well-known redirection techniques to string together a chain of impossible spaces in an expansive outdoor scene. We then conducted an exploratory analysis of users' verbal feedback during exploration, which indicated that impossible spaces provide an even more powerful illusion when users are naive to the manipulation.
Gutiérrez-Maldonado, José; Ferrer-García, Marta; Caqueo-Urízar, Alejandra; Letosa-Porta, Alex
2006-10-01
The aim of this study was to assess the usefulness of virtual environments representing situations that are emotionally significant to subjects with eating disorders (ED). These environments may be applied with both evaluative and therapeutic aims and in simulation procedures to carry out a range of experimental studies. This paper is part of a wider research project analyzing the influence of the situation to which subjects are exposed on their performance on body image estimation tasks. Thirty female patients with eating disorders were exposed to six virtual environments: a living-room (neutral situation), a kitchen with high-calorie food, a kitchen with low-calorie food, a restaurant with high-calorie food, a restaurant with low-calorie food, and a swimming-pool. After exposure to each environment the STAI-S (a measurement of state anxiety) and the CDB (a measurement of depression) were administered to all subjects. The results show that virtual reality instruments are particularly useful for simulating everyday situations that may provoke emotional reactions such as anxiety and depression, in patients with ED. Virtual environments in which subjects are obliged to ingest high-calorie food provoke the highest levels of state anxiety and depression.
The Evolution of Constructivist Learning Environments: Immersion in Distributed, Virtual Worlds.
ERIC Educational Resources Information Center
Dede, Chris
1995-01-01
Discusses the evolution of constructivist learning environments and examines the collaboration of simulated software models, virtual environments, and evolving mental models via immersion in artificial realities. A sidebar gives a realistic example of a student navigating through cyberspace. (JMV)
Real-time recording and classification of eye movements in an immersive virtual environment.
Diaz, Gabriel; Cooper, Joseph; Kit, Dmitry; Hayhoe, Mary
2013-10-10
Despite the growing popularity of virtual reality environments, few laboratories are equipped to investigate eye movements within these environments. This primer is intended to reduce the time and effort required to incorporate eye-tracking equipment into a virtual reality environment. We discuss issues related to the initial startup and provide algorithms necessary for basic analysis. Algorithms are provided for the calculation of gaze angle within a virtual world using a monocular eye-tracker in a three-dimensional environment. In addition, we provide algorithms for the calculation of the angular distance between the gaze and a relevant virtual object and for the identification of fixations, saccades, and pursuit eye movements. Finally, we provide tools that temporally synchronize gaze data and the visual stimulus and enable real-time assembly of a video-based record of the experiment using the Quicktime MOV format, available at http://sourceforge.net/p/utdvrlibraries/. This record contains the visual stimulus, the gaze cursor, and associated numerical data and can be used for data exportation, visual inspection, and validation of calculated gaze movements.
Real-time recording and classification of eye movements in an immersive virtual environment
Diaz, Gabriel; Cooper, Joseph; Kit, Dmitry; Hayhoe, Mary
2013-01-01
Despite the growing popularity of virtual reality environments, few laboratories are equipped to investigate eye movements within these environments. This primer is intended to reduce the time and effort required to incorporate eye-tracking equipment into a virtual reality environment. We discuss issues related to the initial startup and provide algorithms necessary for basic analysis. Algorithms are provided for the calculation of gaze angle within a virtual world using a monocular eye-tracker in a three-dimensional environment. In addition, we provide algorithms for the calculation of the angular distance between the gaze and a relevant virtual object and for the identification of fixations, saccades, and pursuit eye movements. Finally, we provide tools that temporally synchronize gaze data and the visual stimulus and enable real-time assembly of a video-based record of the experiment using the Quicktime MOV format, available at http://sourceforge.net/p/utdvrlibraries/. This record contains the visual stimulus, the gaze cursor, and associated numerical data and can be used for data exportation, visual inspection, and validation of calculated gaze movements. PMID:24113087
Virtual reality training improves students' knowledge structures of medical concepts.
Stevens, Susan M; Goldsmith, Timothy E; Summers, Kenneth L; Sherstyuk, Andrei; Kihmm, Kathleen; Holten, James R; Davis, Christopher; Speitel, Daniel; Maris, Christina; Stewart, Randall; Wilks, David; Saland, Linda; Wax, Diane; Panaiotis; Saiki, Stanley; Alverson, Dale; Caudell, Thomas P
2005-01-01
Virtual environments can provide training that is difficult to achieve under normal circumstances. Medical students can work on high-risk cases in a realistic, time-critical environment, where students practice skills in a cognitively demanding and emotionally compelling situation. Research from cognitive science has shown that as students acquire domain expertise, their semantic organization of core domain concepts become more similar to those of an expert's. In the current study, we hypothesized that students' knowledge structures would become more expert-like as a result of their diagnosing and treating a patient experiencing a hematoma within a virtual environment. Forty-eight medical students diagnosed and treated a hematoma case within a fully immersed virtual environment. Student's semantic organization of 25 case-related concepts was assessed prior to and after training. Students' knowledge structures became more integrated and similar to an expert knowledge structure of the concepts as a result of the learning experience. The methods used here for eliciting, representing, and evaluating knowledge structures offer a sensitive and objective means for evaluating student learning in virtual environments and medical simulations.
Treasure hunt of mineral resources: a serious game in a virtual world
NASA Astrophysics Data System (ADS)
Boniello, Annalisa
2015-04-01
This posterdescribes a geoscience activities on mineral resources for students of 14-18 years old. The activities are created as a treasure hunt of mineral resources, students must pass test and solve questions, search mineral in different environments: near a volcanos, in the river, in a lake, in a cave, under the sea and on a mountain. The activity is created using a virtual environment a virtual world built with a software, Opensim, a opensource software. In this virtual world every student as avatar, a virtual rapresentation of himself, search information, objects, mineral as in a serious game, a digital serious game. In the serious game buit as a treasure hunt, students interact with environment in a learning by doing, and they interact with other students in a cooperative learning and a collaborative environment. In the hunt there is a challenge that student must overcome: understanding what is a mineral resource collecting data on mineral analyzing environments where they are created so the students can improve motivation and learn, and improve scientific skills.
Virtual Jupiter - Real Learning
NASA Astrophysics Data System (ADS)
Ruzhitskaya, Lanika; Speck, A.; Laffey, J.
2010-01-01
How many earthlings went to visit Jupiter? None. How many students visited virtual Jupiter to fulfill their introductory astronomy courses’ requirements? Within next six months over 100 students from University of Missouri will get a chance to explore the planet and its Galilean Moons using a 3D virtual environment created especially for them to learn Kepler's and Newton's laws, eclipses, parallax, and other concepts in astronomy. The virtual world of Jupiter system is a unique 3D environment that allows students to learn course material - physical laws and concepts in astronomy - while engaging them into exploration of the Jupiter's system, encouraging their imagination, curiosity, and motivation. The virtual learning environment let students to work individually or collaborate with their teammates. The 3D world is also a great opportunity for research in astronomy education to investigate impact of social interaction, gaming features, and use of manipulatives offered by a learning tool on students’ motivation and learning outcomes. Use of 3D environment is also a valuable source for exploration of how the learners’ spatial awareness can be enhanced by working in 3-dimensional environment.
Brundage, Shelley B; Hancock, Adrienne B
2015-05-01
Virtual reality environments (VREs) are computer-generated, 3-dimensional worlds that allow users to experience situations similar to those encountered in the real world. The purpose of this study was to investigate VREs for potential use in assessing and treating persons who stutter (PWS) by determining the extent to which PWS's affective, behavioral, and cognitive measures in a VRE correlate with those same measures in a similar live environment. Ten PWS delivered speeches-first to a live audience and, on another day, to 2 virtual audiences (neutral and challenging audiences). Participants completed standard tests of communication apprehension and confidence prior to each condition, and frequency of stuttering was measured during each speech. Correlational analyses revealed significant, positive correlations between virtual and live conditions for affective and cognitive measures as well as for frequency of stuttering. These findings suggest that virtual public speaking environments engender affective, behavioral, and cognitive reactions in PWS that correspond to those experienced in the real world. Therefore, the authentic, safe, and controlled environments provided by VREs may be useful for stuttering assessment and treatment.
ERIC Educational Resources Information Center
Pares-Toral, Maria T.
2013-01-01
The ever increasing popularity of virtual worlds, also known as 3-D multi-user virtual environments (MUVEs) or simply virtual worlds provides language instructors with a new tool they can exploit in their courses. For now, "Second Life" is one of the most popular MUVEs used for teaching and learning, and although "Second Life"…
Virtually-augmented interfaces for tactical aircraft.
Haas, M W
1995-05-01
The term Fusion Interface is defined as a class of interface which integrally incorporates both virtual and non-virtual concepts and devices across the visual, auditory and haptic sensory modalities. A fusion interface is a multi-sensory virtually-augmented synthetic environment. A new facility has been developed within the Human Engineering Division of the Armstrong Laboratory dedicated to exploratory development of fusion-interface concepts. One of the virtual concepts to be investigated in the Fusion Interfaces for Tactical Environments facility (FITE) is the application of EEG and other physiological measures for virtual control of functions within the flight environment. FITE is a specialized flight simulator which allows efficient concept development through the use of rapid prototyping followed by direct experience of new fusion concepts. The FITE facility also supports evaluation of fusion concepts by operational fighter pilots in a high fidelity simulated air combat environment. The facility was utilized by a multi-disciplinary team composed of operational pilots, human-factors engineers, electronics engineers, computer scientists, and experimental psychologists to prototype and evaluate the first multi-sensory, virtually-augmented cockpit. The cockpit employed LCD-based head-down displays, a helmet-mounted display, three-dimensionally localized audio displays, and a haptic display. This paper will endeavor to describe the FITE facility architecture, some of the characteristics of the FITE virtual display and control devices, and the potential application of EEG and other physiological measures within the FITE facility.
Chalil Madathil, Kapil; Greenstein, Joel S
2017-11-01
Collaborative virtual reality-based systems have integrated high fidelity voice-based communication, immersive audio and screen-sharing tools into virtual environments. Such three-dimensional collaborative virtual environments can mirror the collaboration among usability test participants and facilitators when they are physically collocated, potentially enabling moderated usability tests to be conducted effectively when the facilitator and participant are located in different places. We developed a virtual collaborative three-dimensional remote moderated usability testing laboratory and employed it in a controlled study to evaluate the effectiveness of moderated usability testing in a collaborative virtual reality-based environment with two other moderated usability testing methods: the traditional lab approach and Cisco WebEx, a web-based conferencing and screen sharing approach. Using a mixed methods experimental design, 36 test participants and 12 test facilitators were asked to complete representative tasks on a simulated online shopping website. The dependent variables included the time taken to complete the tasks; the usability defects identified and their severity; and the subjective ratings on the workload index, presence and satisfaction questionnaires. Remote moderated usability testing methodology using a collaborative virtual reality system performed similarly in terms of the total number of defects identified, the number of high severity defects identified and the time taken to complete the tasks with the other two methodologies. The overall workload experienced by the test participants and facilitators was the least with the traditional lab condition. No significant differences were identified for the workload experienced with the virtual reality and the WebEx conditions. However, test participants experienced greater involvement and a more immersive experience in the virtual environment than in the WebEx condition. The ratings for the virtual environment condition were not significantly different from those for the traditional lab condition. The results of this study suggest that participants were productive and enjoyed the virtual lab condition, indicating the potential of a virtual world based approach as an alternative to conventional approaches for synchronous usability testing. Copyright © 2017 Elsevier Ltd. All rights reserved.
Envisioning the future of home care: applications of immersive virtual reality.
Brennan, Patricia Flatley; Arnott Smith, Catherine; Ponto, Kevin; Radwin, Robert; Kreutz, Kendra
2013-01-01
Accelerating the design of technologies to support health in the home requires 1) better understanding of how the household context shapes consumer health behaviors and (2) the opportunity to afford engineers, designers, and health professionals the chance to systematically study the home environment. We developed the Living Environments Laboratory (LEL) with a fully immersive, six-sided virtual reality CAVE to enable recreation of a broad range of household environments. We have successfully developed a virtual apartment, including a kitchen, living space, and bathroom. Over 2000 people have visited the LEL CAVE. Participants use an electronic wand to activate common household affordances such as opening a refrigerator door or lifting a cup. Challenges currently being explored include creating natural gesture to interface with virtual objects, developing robust, simple procedures to capture actual living environments and rendering them in a 3D visualization, and devising systematic stable terminologies to characterize home environments.
Virtual Learning Environment for Interactive Engagement with Advanced Quantum Mechanics
NASA Astrophysics Data System (ADS)
Pedersen, Mads Kock; Skyum, Birk; Heck, Robert; Müller, Romain; Bason, Mark; Lieberoth, Andreas; Sherson, Jacob F.
2016-06-01
A virtual learning environment can engage university students in the learning process in ways that the traditional lectures and lab formats cannot. We present our virtual learning environment StudentResearcher, which incorporates simulations, multiple-choice quizzes, video lectures, and gamification into a learning path for quantum mechanics at the advanced university level. StudentResearcher is built upon the experiences gathered from workshops with the citizen science game Quantum Moves at the high-school and university level, where the games were used extensively to illustrate the basic concepts of quantum mechanics. The first test of this new virtual learning environment was a 2014 course in advanced quantum mechanics at Aarhus University with 47 enrolled students. We found increased learning for the students who were more active on the platform independent of their previous performances.
Visualizing vascular structures in virtual environments
NASA Astrophysics Data System (ADS)
Wischgoll, Thomas
2013-01-01
In order to learn more about the cause of coronary heart diseases and develop diagnostic tools, the extraction and visualization of vascular structures from volumetric scans for further analysis is an important step. By determining a geometric representation of the vasculature, the geometry can be inspected and additional quantitative data calculated and incorporated into the visualization of the vasculature. To provide a more user-friendly visualization tool, virtual environment paradigms can be utilized. This paper describes techniques for interactive rendering of large-scale vascular structures within virtual environments. This can be applied to almost any virtual environment configuration, such as CAVE-type displays. Specifically, the tools presented in this paper were tested on a Barco I-Space and a large 62x108 inch passive projection screen with a Kinect sensor for user tracking.
Hybrid Cloud Computing Environment for EarthCube and Geoscience Community
NASA Astrophysics Data System (ADS)
Yang, C. P.; Qin, H.
2016-12-01
The NSF EarthCube Integration and Test Environment (ECITE) has built a hybrid cloud computing environment to provides cloud resources from private cloud environments by using cloud system software - OpenStack and Eucalyptus, and also manages public cloud - Amazon Web Service that allow resource synchronizing and bursting between private and public cloud. On ECITE hybrid cloud platform, EarthCube and geoscience community can deploy and manage the applications by using base virtual machine images or customized virtual machines, analyze big datasets by using virtual clusters, and real-time monitor the virtual resource usage on the cloud. Currently, a number of EarthCube projects have deployed or started migrating their projects to this platform, such as CHORDS, BCube, CINERGI, OntoSoft, and some other EarthCube building blocks. To accomplish the deployment or migration, administrator of ECITE hybrid cloud platform prepares the specific needs (e.g. images, port numbers, usable cloud capacity, etc.) of each project in advance base on the communications between ECITE and participant projects, and then the scientists or IT technicians in those projects launch one or multiple virtual machines, access the virtual machine(s) to set up computing environment if need be, and migrate their codes, documents or data without caring about the heterogeneity in structure and operations among different cloud platforms.
NASA Astrophysics Data System (ADS)
Watanuki, Keiichi; Kojima, Kazuyuki
The environment in which Japanese industry has achieved great respect is changing tremendously due to the globalization of world economies, while Asian countries are undergoing economic and technical development as well as benefiting from the advances in information technology. For example, in the design of custom-made casting products, a designer who lacks knowledge of casting may not be able to produce a good design. In order to obtain a good design and manufacturing result, it is necessary to equip the designer and manufacturer with a support system related to casting design, or a so-called knowledge transfer and creation system. This paper proposes a new virtual reality based knowledge acquisition and job training system for casting design, which is composed of the explicit and tacit knowledge transfer systems using synchronized multimedia and the knowledge internalization system using portable virtual environment. In our proposed system, the education content is displayed in the immersive virtual environment, whereby a trainee may experience work in the virtual site operation. Provided that the trainee has gained explicit and tacit knowledge of casting through the multimedia-based knowledge transfer system, the immersive virtual environment catalyzes the internalization of knowledge and also enables the trainee to gain tacit knowledge before undergoing on-the-job training at a real-time operation site.
Learning Rationales and Virtual Reality Technology in Education.
ERIC Educational Resources Information Center
Chiou, Guey-Fa
1995-01-01
Defines and describes virtual reality technology and differentiates between virtual learning environment, learning material, and learning tools. Links learning rationales to virtual reality technology to pave conceptual foundations for application of virtual reality technology education. Constructivism, case-based learning, problem-based learning,…
A Multi-User Virtual Environment for Building and Assessing Higher Order Inquiry Skills in Science
ERIC Educational Resources Information Center
Ketelhut, Diane Jass; Nelson, Brian C.; Clarke, Jody; Dede, Chris
2010-01-01
This study investigated novel pedagogies for helping teachers infuse inquiry into a standards-based science curriculum. Using a multi-user virtual environment (MUVE) as a pedagogical vehicle, teams of middle-school students collaboratively solved problems around disease in a virtual town called River City. The students interacted with "avatars" of…
ERIC Educational Resources Information Center
Keskitalo, Tuulikki
2011-01-01
This research article focuses on virtual reality (VR) and simulation-based training, with a special focus on the pedagogical use of the Virtual Centre of Wellness Campus known as ENVI (Rovaniemi, Finland). In order to clearly understand how teachers perceive teaching and learning in such environments, this research examines the concepts of…
Virtual Worlds as the Next Asset of Virtual Learning Environments for Students in Business?
ERIC Educational Resources Information Center
Pelet, Jean-Eric; Lecat, Benoît
2012-01-01
The authors' research examines the effectiveness of a web-based virtual learning environment (VLE) in the context of management studies. This article provides two main contributions. First, an exploratory study introduces and describes the concept of VLE applied to the training of seven students in an "interactivity design" (IS) course.…
ERIC Educational Resources Information Center
Frank, Christine; Kassanke, Stephan; Suhl, Leena
This paper addresses the importance of assessing and realizing students' needs and expectations while developing a virtual learning environment (VLE). The project Virtual OR/MS is funded by the Federal Ministry of Education and Research of the German Government. It involves seven German partners from six universities. The goal of the project…
Power, Influence Tactics, and Influence Processes in Virtual Teams
ERIC Educational Resources Information Center
Boughton, Marla
2011-01-01
Current studies of power, influence tactics, and influence processes in virtual teams assume that these constructs operate in a similar manner as they do in the face-to-face (FtF) environment. However, the virtual context differs from the FtF environment on a variety of dimensions, such as the availability of status cues. The differences between…
ERIC Educational Resources Information Center
Mohamed, Fahim; Abdeslam, Jakimi; Lahcen, El Bermi
2017-01-01
Virtual Environments for Training (VET) are useful tools for visualization, discovery as well as for training. VETs are based on virtual reality technique to put learners in training situations that emulate genuine situations. VETs have proven to be advantageous in putting learners into varied training situations to acquire knowledge and…
Civic Participation among Seventh-Grade Social Studies Students in Multi-User Virtual Environments
ERIC Educational Resources Information Center
Zieger, Laura; Farber, Matthew
2012-01-01
Technological advances on the Internet now enable students to develop participation skills in virtual worlds. Similar to controlling a character in a video game, multi-user virtual environments, or MUVEs, allow participants to interact with others in synchronous, online settings. The authors of this study created a link between MUVEs and…
Mitigating Challenges of Using Virtual Reality in Online Courses: A Case Study
ERIC Educational Resources Information Center
Stewart, Barbara; Hutchins, Holly M.; Ezell, Shirley; De Martino, Darrell; Bobba, Anil
2010-01-01
Case study methodology was used to describe the challenges experienced in the development of a virtual component for a freshman-level undergraduate course. The purpose of the project was to use a virtual environment component to provide an interactive and engaging learning environment. While some student and faculty feedback was positive, this…
ERIC Educational Resources Information Center
Ahmed, Iftekhar
2009-01-01
Virtual Research Environments (VRE) are electronic meeting places for interaction among scientists created by combining software tools and computer networking. Virtual teams are enjoying increased importance in the conduct of scientific research because of the rising cost of traditional scientific scholarly communication, the growing importance of…
ERIC Educational Resources Information Center
Sadler, Randall
2012-01-01
This book focuses on one area in the field of Computer-Mediated Communication that has recently exploded in popularity--Virtual Worlds. Virtual Worlds are online multiplayer three-dimensional environments where avatars represent their real world counterparts. In particular, this text explores the potential for these environments to be used for…
A Study of Faculty's Role in a Virtual Environment in Iran
ERIC Educational Resources Information Center
Kian, Maryam
2014-01-01
"Faculty" is one element of virtual education curricula that facilitates the learning process. However, the lack of physical presence has led to a need to redefine the faculty role. This qualitative study considered the changing roles of faculty in virtual environments in universities in Iran. The main question was What role(s) do…
ERIC Educational Resources Information Center
Shelton, Angela
2012-01-01
Many United States secondary students perform poorly on standardized summative science assessments. Situated Assessments using Virtual Environments (SAVE) Science is an innovative assessment project that seeks to capture students' science knowledge and understanding by contextualizing problems in a game-based virtual environment called…
ERIC Educational Resources Information Center
Dukas, Georg
2009-01-01
Though research in emerging technologies is vital to fulfilling their incredible potential for educational applications, it is often fraught with analytic challenges related to large datasets. This thesis explores these challenges in researching multiuser virtual environments (MUVEs). In a MUVE, users assume a persona and traverse a virtual space…
ERIC Educational Resources Information Center
Lawless-Reljic, Sabine Karine
2010-01-01
Growing interest of educational institutions in desktop 3D graphic virtual environments for hybrid and distance education prompts questions on the efficacy of such tools. Virtual worlds, such as Second Life[R], enable computer-mediated immersion and interactions encompassing multimodal communication channels including audio, video, and text-.…
ERIC Educational Resources Information Center
Abeldina, Zhaidary; Moldumarova, Zhibek; Abeldina, Rauza; Makysh, Gulmira; Moldumarova, Zhuldyz Ilibaevna
2016-01-01
This work reports on the use of virtual tools as means of learning process activation. A good result can be achieved by combining the classical learning with modern computer technology. By creating a virtual learning environment and using multimedia learning tools one can obtain a significant result while facilitating the development of students'…
ERIC Educational Resources Information Center
Kim, Mi Hwa
2013-01-01
The purpose of this experimental study was to investigate the impact of the use of a virtual environment for learning Korean history on high school students' learning outcomes and attitudes toward virtual worlds (collaboration, engagement, general use of SL [Second Life], and immersion). In addition, this experiment examined the relationships…
3D Virtual Learning Environments in Education: A Meta-Review
ERIC Educational Resources Information Center
Reisoglu, I.; Topu, B.; Yilmaz, R.; Karakus Yilmaz, T.; Göktas, Y.
2017-01-01
The aim of this study is to investigate recent empirical research studies about 3D virtual learning environments. A total of 167 empirical studies that involve the use of 3D virtual worlds in education were examined by meta-review. Our findings show that the "Second Life" platform has been frequently used in studies. Among the reviewed…
Virtual Environments as a Tool for Improving Sequence Ability of Deaf and Hard of Hearing Children
ERIC Educational Resources Information Center
Eden, Sigal; Ingber, Sara
2014-01-01
The study examined the efficacy of an early intervention program to improve children's sequential time perception through virtual versus pictorial training in arranging episodes of temporal scripts. The researchers examined 65 deaf and hard of hearing children ages 4-7 years who were divided into two groups: (a) virtual environments technological…
A training system of orientation and mobility for blind people using acoustic virtual reality.
Seki, Yoshikazu; Sato, Tetsuji
2011-02-01
A new auditory orientation training system was developed for blind people using acoustic virtual reality (VR) based on a head-related transfer function (HRTF) simulation. The present training system can reproduce a virtual training environment for orientation and mobility (O&M) instruction, and the trainee can walk through the virtual training environment safely by listening to sounds such as vehicles, stores, ambient noise, etc., three-dimensionally through headphones. The system can reproduce not only sound sources but also sound reflection and insulation, so that the trainee can learn both sound location and obstacle perception skills. The virtual training environment is described in extensible markup language (XML), and the O&M instructor can edit it easily according to the training curriculum. Evaluation experiments were conducted to test the efficiency of some features of the system. Thirty subjects who had not acquired O&M skills attended the experiments. The subjects were separated into three groups: a no-training group, a virtual-training group using the present system, and a real-training group in real environments. The results suggested that virtual-training can reduce "veering" more than real-training and also can reduce stress as much as real training. The subjective technical and anxiety scores also improved.
NASA Technical Reports Server (NTRS)
Searcy, Brittani
2017-01-01
Using virtual environments to assess complex large scale human tasks provides timely and cost effective results to evaluate designs and to reduce operational risks during assembly and integration of the Space Launch System (SLS). NASA's Marshall Space Flight Center (MSFC) uses a suite of tools to conduct integrated virtual analysis during the design phase of the SLS Program. Siemens Jack is a simulation tool that allows engineers to analyze human interaction with CAD designs by placing a digital human model into the environment to test different scenarios and assess the design's compliance to human factors requirements. Engineers at MSFC are using Jack in conjunction with motion capture and virtual reality systems in MSFC's Virtual Environments Lab (VEL). The VEL provides additional capability beyond standalone Jack to record and analyze a person performing a planned task to assemble the SLS at Kennedy Space Center (KSC). The VEL integrates Vicon Blade motion capture system, Siemens Jack, Oculus Rift, and other virtual tools to perform human factors assessments. By using motion capture and virtual reality, a more accurate breakdown and understanding of how an operator will perform a task can be gained. By virtual analysis, engineers are able to determine if a specific task is capable of being safely performed by both a 5% (approx. 5ft) female and a 95% (approx. 6'1) male. In addition, the analysis will help identify any tools or other accommodations that may to help complete the task. These assessments are critical for the safety of ground support engineers and keeping launch operations on schedule. Motion capture allows engineers to save and examine human movements on a frame by frame basis, while virtual reality gives the actor (person performing a task in the VEL) an immersive view of the task environment. This presentation will discuss the need of human factors for SLS and the benefits of analyzing tasks in NASA MSFC's VEL.
Encarnação, L Miguel; Bimber, Oliver
2002-01-01
Collaborative virtual environments for diagnosis and treatment planning are increasingly gaining importance in our global society. Virtual and Augmented Reality approaches promised to provide valuable means for the involved interactive data analysis, but the underlying technologies still create a cumbersome work environment that is inadequate for clinical employment. This paper addresses two of the shortcomings of such technology: Intuitive interaction with multi-dimensional data in immersive and semi-immersive environments as well as stereoscopic multi-user displays combining the advantages of Virtual and Augmented Reality technology.
Miller, Haylie L.; Bugnariu, Nicoleta; Patterson, Rita M.; Wijayasinghe, Indika; Popa, Dan O.
2018-01-01
Visuomotor integration (VMI), the use of visual information to guide motor planning, execution, and modification, is necessary for a wide range of functional tasks. To comprehensively, quantitatively assess VMI, we developed a paradigm integrating virtual environments, motion-capture, and mobile eye-tracking. Virtual environments enable tasks to be repeatable, naturalistic, and varied in complexity. Mobile eye-tracking and minimally-restricted movement enable observation of natural strategies for interacting with the environment. This paradigm yields a rich dataset that may inform our understanding of VMI in typical and atypical development. PMID:29876370
Trees, Jason; Snider, Joseph; Falahpour, Maryam; Guo, Nick; Lu, Kun; Johnson, Douglas C; Poizner, Howard; Liu, Thomas T
2014-01-01
Hyperscanning, an emerging technique in which data from multiple interacting subjects' brains are simultaneously recorded, has become an increasingly popular way to address complex topics, such as "theory of mind." However, most previous fMRI hyperscanning experiments have been limited to abstract social interactions (e.g. phone conversations). Our new method utilizes a virtual reality (VR) environment used for military training, Virtual Battlespace 2 (VBS2), to create realistic avatar-avatar interactions and cooperative tasks. To control the virtual avatar, subjects use a MRI compatible Playstation 3 game controller, modified by removing all extraneous metal components and replacing any necessary ones with 3D printed plastic models. Control of both scanners' operation is initiated by a VBS2 plugin to sync scanner time to the known time within the VR environment. Our modifications include:•Modification of game controller to be MRI compatible.•Design of VBS2 virtual environment for cooperative interactions.•Syncing two MRI machines for simultaneous recording.
The experiment editor: supporting inquiry-based learning with virtual labs
NASA Astrophysics Data System (ADS)
Galan, D.; Heradio, R.; de la Torre, L.; Dormido, S.; Esquembre, F.
2017-05-01
Inquiry-based learning is a pedagogical approach where students are motivated to pose their own questions when facing problems or scenarios. In physics learning, students are turned into scientists who carry out experiments, collect and analyze data, formulate and evaluate hypotheses, and so on. Lab experimentation is essential for inquiry-based learning, yet there is a drawback with traditional hands-on labs in the high costs associated with equipment, space, and maintenance staff. Virtual laboratories are helpful to reduce these costs. This paper enriches the virtual lab ecosystem by providing an integrated environment to automate experimentation tasks. In particular, our environment supports: (i) scripting and running experiments on virtual labs, and (ii) collecting and analyzing data from the experiments. The current implementation of our environment supports virtual labs created with the authoring tool Easy Java/Javascript Simulations. Since there are public repositories with hundreds of freely available labs created with this tool, the potential applicability to our environment is considerable.
Trees, Jason; Snider, Joseph; Falahpour, Maryam; Guo, Nick; Lu, Kun; Johnson, Douglas C.; Poizner, Howard; Liu, Thomas T.
2014-01-01
Hyperscanning, an emerging technique in which data from multiple interacting subjects’ brains are simultaneously recorded, has become an increasingly popular way to address complex topics, such as “theory of mind.” However, most previous fMRI hyperscanning experiments have been limited to abstract social interactions (e.g. phone conversations). Our new method utilizes a virtual reality (VR) environment used for military training, Virtual Battlespace 2 (VBS2), to create realistic avatar-avatar interactions and cooperative tasks. To control the virtual avatar, subjects use a MRI compatible Playstation 3 game controller, modified by removing all extraneous metal components and replacing any necessary ones with 3D printed plastic models. Control of both scanners’ operation is initiated by a VBS2 plugin to sync scanner time to the known time within the VR environment. Our modifications include:•Modification of game controller to be MRI compatible.•Design of VBS2 virtual environment for cooperative interactions.•Syncing two MRI machines for simultaneous recording. PMID:26150964
BIM based virtual environment for fire emergency evacuation.
Wang, Bin; Li, Haijiang; Rezgui, Yacine; Bradley, Alex; Ong, Hoang N
2014-01-01
Recent building emergency management research has highlighted the need for the effective utilization of dynamically changing building information. BIM (building information modelling) can play a significant role in this process due to its comprehensive and standardized data format and integrated process. This paper introduces a BIM based virtual environment supported by virtual reality (VR) and a serious game engine to address several key issues for building emergency management, for example, timely two-way information updating and better emergency awareness training. The focus of this paper lies on how to utilize BIM as a comprehensive building information provider to work with virtual reality technologies to build an adaptable immersive serious game environment to provide real-time fire evacuation guidance. The innovation lies on the seamless integration between BIM and a serious game based virtual reality (VR) environment aiming at practical problem solving by leveraging state-of-the-art computing technologies. The system has been tested for its robustness and functionality against the development requirements, and the results showed promising potential to support more effective emergency management.
Accurately Decoding Visual Information from fMRI Data Obtained in a Realistic Virtual Environment
2015-06-09
Center for Learning and Memory , The University of Texas at Austin, 100 E 24th Street, Stop C7000, Austin, TX 78712, USA afloren@utexas.edu Received: 18...information from fMRI data obtained in a realistic virtual environment. Front. Hum. Neurosci. 9:327. doi: 10.3389/fnhum.2015.00327 Accurately decoding...visual information from fMRI data obtained in a realistic virtual environment Andrew Floren 1*, Bruce Naylor 2, Risto Miikkulainen 3 and David Ress 4
Lorenz, D; Armbruster, W; Vogelgesang, C; Hoffmann, H; Pattar, A; Schmidt, D; Volk, T; Kubulus, D
2016-09-01
Chief emergency physicians are regarded as an important element in the care of the injured and sick following mass casualty accidents. Their education is very theoretical; practical content in contrast often falls short. Limitations are usually the very high costs of realistic (large-scale) exercises, poor reproducibility of the scenarios, and poor corresponding results. To substantially improve the educational level because of the complexity of mass casualty accidents, modified training concepts are required that teach the not only the theoretical but above all the practical skills considerably more intensively than at present. Modern training concepts should make it possible for the learner to realistically simulate decision processes. This article examines how interactive virtual environments are applicable for the education of emergency personnel and how they could be designed. Virtual simulation and training environments offer the possibility of simulating complex situations in an adequately realistic manner. The so-called virtual reality (VR) used in this context is an interface technology that enables free interaction in addition to a stereoscopic and spatial representation of virtual large-scale emergencies in a virtual environment. Variables in scenarios such as the weather, the number wounded, and the availability of resources, can be changed at any time. The trainees are able to practice the procedures in many virtual accident scenes and act them out repeatedly, thereby testing the different variants. With the aid of the "InSitu" project, it is possible to train in a virtual reality with realistically reproduced accident situations. These integrated, interactive training environments can depict very complex situations on a scale of 1:1. Because of the highly developed interactivity, the trainees can feel as if they are a direct part of the accident scene and therefore identify much more with the virtual world than is possible with desktop systems. Interactive, identifiable, and realistic training environments based on projector systems could in future enable a repetitive exercise with changes within a decision tree, in reproducibility, and within different occupational groups. With a hard- and software environment numerous accident situations can be depicted and practiced. The main expense is the creation of the virtual accident scenes. As the appropriate city models and other three-dimensional geographical data are already available, this expenditure is very low compared with the planning costs of a large-scale exercise.
Tools for Teaching Virtual Teams: A Comparative Resource Review
ERIC Educational Resources Information Center
Larson, Barbara; Leung, Opal; Mullane, Kenneth
2017-01-01
As the ubiquity of virtual work--and particularly virtual project teams--increases in the professional environment, management and other professional programs are increasingly teaching students skills related to virtual work. One of the most common forms of teaching virtual work skills is a virtual team project, in which students collaborate with…
Virtual odors to transmit emotions in virtual agents
NASA Astrophysics Data System (ADS)
Delgado-Mata, Carlos; Aylett, Ruth
2003-04-01
In this paper we describe an emotional-behvioral architecture. The emotional engine sits at a higher layer than the behavior system, and can alter behavior patterns, the engine is designed to simulate Emotionally-Intelligent Agents in a Virtual Environment, where each agent senses its own emotions, and other creature emotions through a virtual smell sensor; senses obstacles and other moving creatures in the environment and reacts to them. The architecture consists of an emotion engine, behavior synthesis system, a motor layer and a library of sensors.
Virtual Glovebox (VGX) Aids Astronauts in Pre-Flight Training
NASA Technical Reports Server (NTRS)
2003-01-01
NASA's Virtual Glovebox (VGX) was developed to allow astronauts on Earth to train for complex biology research tasks in space. The astronauts may reach into the virtual environment, naturally manipulating specimens, tools, equipment, and accessories in a simulated microgravity environment as they would do in space. Such virtual reality technology also provides engineers and space operations staff with rapid prototyping, planning, and human performance modeling capabilities. Other Earth based applications being explored for this technology include biomedical procedural training and training for disarming bio-terrorism weapons.
Age effect on components of episodic memory and feature binding: A virtual reality study.
Plancher, Gaën; Gyselinck, Valerie; Nicolas, Serge; Piolino, Pascale
2010-05-01
The aims were (1) to explore the effects of normal aging on the main aspects of episodic memory--what, where, and when,--and on feature binding in a virtual environment; (2) to explore the influence of the mode of learning, intentional versus incidental; and (3) to benchmark virtual environment findings collected with older adults against data recorded in classical neuropsychological tests. We tested a population of 82 young adults and 78 older adults without dementia (they participated in a short battery of neuropsychological tests). All the participants drove a car in an urban virtual environment composing of 9 turns and specific areas. Half of the participants were told to drive through the virtual town; the other half were asked to drive and to memorize the environment (itinerary, elements, etc.). All aspects of episodic memory were then assessed (what, where, when, and binding). The older participants had less recollection of the spatiotemporal context of events than the younger with intentional encoding (p < .001), but similar recollection with incidental encoding (except for verbal spatial aspect). The younger participants showed better binding than older ones regardless of the type of encoding (p < .001). For the older participants the virtual test was sensitive to mnesic complaints as well as general cognitive changes (p < .05 to p < .01). We view these results as an indication that virtual environments could provide helpful standard tools for assessing age effects on the main aspects of episodic memory.
Virtual reality conditioned place preference using monetary reward
Childs, Emma; Astur, Robert S.; de Wit, Harriet
2017-01-01
Computerized tasks based on conditioned place preference (CPP) methodology offer the opportunity to study learning mechanisms involved in conditioned reward in humans. In this study, we examined acquisition and extinction of a CPP for virtual environments associated with monetary reward ($). Healthy men and women (N=57) completed a computerized CPP task in which they controlled an avatar within a virtual environment. On day 1, subjects completed 6 conditioning trials in which one room was paired with high $ and another with low $. Acquisition of place conditioning was assessed by measuring the time spent in each room during an exploration test of the virtual environments and using self-reported ratings of room liking and preference. Twenty-four hours later, retention and extinction of CPP were assessed during 4 successive exploration tests of the virtual environments. Participants exhibited a place preference for (spent significantly more time in) the virtual room paired with high $ over the one paired with low $ (p=0.015). They also reported that they preferred the high $ room (p<0.001) and liked it significantly more than the low $ room (p<0.001). However, these preferences were short-lived: 24h later subjects did not exhibit a behavioral or subjective preference for the high $ room. These findings show that individuals exhibit transient behavioral and subjective preferences for a virtual environment paired with monetary reward. Variations on this task may be useful to study mechanisms and brain substrates involved in conditioned reward and to examine the influence of drugs upon appetitive conditioning. PMID:28108321
Immersive virtual reality for visualization of abdominal CT
NASA Astrophysics Data System (ADS)
Lin, Qiufeng; Xu, Zhoubing; Li, Bo; Baucom, Rebeccah; Poulose, Benjamin; Landman, Bennett A.; Bodenheimer, Robert E.
2013-03-01
Immersive virtual environments use a stereoscopic head-mounted display and data glove to create high fidelity virtual experiences in which users can interact with three-dimensional models and perceive relationships at their true scale. This stands in stark contrast to traditional PACS-based infrastructure in which images are viewed as stacks of two dimensional slices, or, at best, disembodied renderings. Although there has substantial innovation in immersive virtual environments for entertainment and consumer media, these technologies have not been widely applied in clinical applications. Here, we consider potential applications of immersive virtual environments for ventral hernia patients with abdominal computed tomography imaging data. Nearly a half million ventral hernias occur in the United States each year, and hernia repair is the most commonly performed general surgery operation worldwide. A significant problem in these conditions is communicating the urgency, degree of severity, and impact of a hernia (and potential repair) on patient quality of life. Hernias are defined by ruptures in the abdominal wall (i.e., the absence of healthy tissues) rather than a growth (e.g., cancer); therefore, understanding a hernia necessitates understanding the entire abdomen. Our environment allows surgeons and patients to view body scans at scale and interact with these virtual models using a data glove. This visualization and interaction allows users to perceive the relationship between physical structures and medical imaging data. The system provides close integration of PACS-based CT data with immersive virtual environments and creates opportunities to study and optimize interfaces for patient communication, operative planning, and medical education.
Immersive Virtual Reality for Visualization of Abdominal CT.
Lin, Qiufeng; Xu, Zhoubing; Li, Bo; Baucom, Rebeccah; Poulose, Benjamin; Landman, Bennett A; Bodenheimer, Robert E
2013-03-28
Immersive virtual environments use a stereoscopic head-mounted display and data glove to create high fidelity virtual experiences in which users can interact with three-dimensional models and perceive relationships at their true scale. This stands in stark contrast to traditional PACS-based infrastructure in which images are viewed as stacks of two-dimensional slices, or, at best, disembodied renderings. Although there has substantial innovation in immersive virtual environments for entertainment and consumer media, these technologies have not been widely applied in clinical applications. Here, we consider potential applications of immersive virtual environments for ventral hernia patients with abdominal computed tomography imaging data. Nearly a half million ventral hernias occur in the United States each year, and hernia repair is the most commonly performed general surgery operation worldwide. A significant problem in these conditions is communicating the urgency, degree of severity, and impact of a hernia (and potential repair) on patient quality of life. Hernias are defined by ruptures in the abdominal wall (i.e., the absence of healthy tissues) rather than a growth (e.g., cancer); therefore, understanding a hernia necessitates understanding the entire abdomen. Our environment allows surgeons and patients to view body scans at scale and interact with these virtual models using a data glove. This visualization and interaction allows users to perceive the relationship between physical structures and medical imaging data. The system provides close integration of PACS-based CT data with immersive virtual environments and creates opportunities to study and optimize interfaces for patient communication, operative planning, and medical education.
The development of the virtual reality system for the treatment of the fears of public speaking.
Jo, H J; Ku, J H; Jang, D P; Shin, M B; Ahn, H B; Lee, J M; Cho, B H; Kim, S I
2001-01-01
The fear of public speaking is a kind of social phobias. The patients having the fear of public speaking show some symptoms like shame and timidity in the daily personal relationship. They are afraid that the other person would be puzzled, feel insulted, and they also fear that they should be underestimated for their mistakes. For the treatment of the fear of public speaking, the cognitive-behavioral therapy has been generally used. The cognitive-behavioral therapy is the method that makes the patients gradually experience some situations inducing the fears and overcome those at last. Recently, the virtual reality technology has been introduced as an alternative method for providing phobic situations. In this study, we developed the public speaking simulator and the virtual environments for the treatment of the fear of public speaking. The head-mounted display, the head-tracker and the 3 dimensional sound system were used for the immersive virtual environment. The imagery of the virtual environment consists of a seminar room and 8 virtual audiences. The patient will speak in front of these virtual audiences and the therapist can control motions, facial expressions, sounds, and voices of each virtual audience.
Creation of virtual patients for midwifery education.
Urbanová, Eva; Bašková, Martina; Maskálová, Erika; Kvaltínyová, Eva
2018-07-01
The objective of the study was to create several new, original virtual patients (VPs) in the Slovak language, especially for educational purposes in midwifery. Virtual patients have been created for the needs of university midwifery education in Slovakia. The creation of the six virtual patients basically consisted of three fixed stages: preparation, design and development, implementation into the virtual environment. We used the Open Labyrinth (OL) virtual environment, an open-source system for creating VPs. The VPs include six various scenarios of the most common problems seen in midwifery practice: preterm birth, perinatal loss, gestational diabetes, ineffective breastfeeding, postpartum bleeding and sudden home birth. Currently, six original virtual patients are used in university midwifery education in Slovakia. We use them for contact teaching as well as self-study of students. They present the first VPs in Slovakia and the Czech Republic created in academic settings in these countries. The future perspective of a virtual patient as an interactive process between the student and the medium is that it can deepen and improve learning outcomes, solve specific midwifery issues, and reduce mistakes in the clinical environment. Copyright © 2018 Elsevier Ltd. All rights reserved.
System-Level Virtualization for High Performance Computing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vallee, Geoffroy R; Naughton, III, Thomas J; Engelmann, Christian
2008-01-01
System-level virtualization has been a research topic since the 70's but regained popularity during the past few years because of the availability of efficient solution such as Xen and the implementation of hardware support in commodity processors (e.g. Intel-VT, AMD-V). However, a majority of system-level virtualization projects is guided by the server consolidation market. As a result, current virtualization solutions appear to not be suitable for high performance computing (HPC) which is typically based on large-scale systems. On another hand there is significant interest in exploiting virtual machines (VMs) within HPC for a number of other reasons. By virtualizing themore » machine, one is able to run a variety of operating systems and environments as needed by the applications. Virtualization allows users to isolate workloads, improving security and reliability. It is also possible to support non-native environments and/or legacy operating environments through virtualization. In addition, it is possible to balance work loads, use migration techniques to relocate applications from failing machines, and isolate fault systems for repair. This document presents the challenges for the implementation of a system-level virtualization solution for HPC. It also presents a brief survey of the different approaches and techniques to address these challenges.« less
NASA Astrophysics Data System (ADS)
Tsoupikova, Daria
2006-02-01
This paper will explore how the aesthetics of the virtual world affects, transforms, and enhances the immersive emotional experience of the user. What we see and what we do upon entering the virtual environment influences our feelings, mental state, physiological changes and sensibility. To create a unique virtual experience the important component to design is the beauty of the virtual world based on the aesthetics of the graphical objects such as textures, models, animation, and special effects. The aesthetic potency of the images that comprise the virtual environment can make the immersive experience much stronger and more compelling. The aesthetic qualities of the virtual world as born out through images and graphics can influence the user's state of mind. Particular changes and effects on the user can be induced through the application of techniques derived from the research fields of psychology, anthropology, biology, color theory, education, art therapy, music, and art history. Many contemporary artists and developers derive much inspiration for their work from their experience with traditional arts such as painting, sculpture, design, architecture and music. This knowledge helps them create a higher quality of images and stereo graphics in the virtual world. The understanding of the close relation between the aesthetic quality of the virtual environment and the resulting human perception is the key to developing an impressive virtual experience.
Authoring Adaptive 3D Virtual Learning Environments
ERIC Educational Resources Information Center
Ewais, Ahmed; De Troyer, Olga
2014-01-01
The use of 3D and Virtual Reality is gaining interest in the context of academic discussions on E-learning technologies. However, the use of 3D for learning environments also has drawbacks. One way to overcome these drawbacks is by having an adaptive learning environment, i.e., an environment that dynamically adapts to the learner and the…
Development of visual 3D virtual environment for control software
NASA Technical Reports Server (NTRS)
Hirose, Michitaka; Myoi, Takeshi; Amari, Haruo; Inamura, Kohei; Stark, Lawrence
1991-01-01
Virtual environments for software visualization may enable complex programs to be created and maintained. A typical application might be for control of regional electric power systems. As these encompass broader computer networks than ever, construction of such systems becomes very difficult. Conventional text-oriented environments are useful in programming individual processors. However, they are obviously insufficient to program a large and complicated system, that includes large numbers of computers connected to each other; such programming is called 'programming in the large.' As a solution for this problem, the authors are developing a graphic programming environment wherein one can visualize complicated software in virtual 3D world. One of the major features of the environment is the 3D representation of concurrent process. 3D representation is used to supply both network-wide interprocess programming capability (capability for 'programming in the large') and real-time programming capability. The authors' idea is to fuse both the block diagram (which is useful to check relationship among large number of processes or processors) and the time chart (which is useful to check precise timing for synchronization) into a single 3D space. The 3D representation gives us a capability for direct and intuitive planning or understanding of complicated relationship among many concurrent processes. To realize the 3D representation, a technology to enable easy handling of virtual 3D object is a definite necessity. Using a stereo display system and a gesture input device (VPL DataGlove), our prototype of the virtual workstation has been implemented. The workstation can supply the 'sensation' of the virtual 3D space to a programmer. Software for the 3D programming environment is implemented on the workstation. According to preliminary assessments, a 50 percent reduction of programming effort is achieved by using the virtual 3D environment. The authors expect that the 3D environment has considerable potential in the field of software engineering.
Virtual Representations in 3D Learning Environments
ERIC Educational Resources Information Center
Shonfeld, Miri; Kritz, Miki
2013-01-01
This research explores the extent to which virtual worlds can serve as online collaborative learning environments for students by increasing social presence and engagement. 3D environments enable learning, which simulates face-to-face encounters while retaining the advantages of online learning. Students in Education departments created avatars…
Adaptive User Model for Web-Based Learning Environment.
ERIC Educational Resources Information Center
Garofalakis, John; Sirmakessis, Spiros; Sakkopoulos, Evangelos; Tsakalidis, Athanasios
This paper describes the design of an adaptive user model and its implementation in an advanced Web-based Virtual University environment that encompasses combined and synchronized adaptation between educational material and well-known communication facilities. The Virtual University environment has been implemented to support a postgraduate…
Linkenauger, Sally A.; Leyrer, Markus; Bülthoff, Heinrich H.; Mohler, Betty J.
2013-01-01
The notion of body-based scaling suggests that our body and its action capabilities are used to scale the spatial layout of the environment. Here we present four studies supporting this perspective by showing that the hand acts as a metric which individuals use to scale the apparent sizes of objects in the environment. However to test this, one must be able to manipulate the size and/or dimensions of the perceiver’s hand which is difficult in the real world due to impliability of hand dimensions. To overcome this limitation, we used virtual reality to manipulate dimensions of participants’ fully-tracked, virtual hands to investigate its influence on the perceived size and shape of virtual objects. In a series of experiments, using several measures, we show that individuals’ estimations of the sizes of virtual objects differ depending on the size of their virtual hand in the direction consistent with the body-based scaling hypothesis. Additionally, we found that these effects were specific to participants’ virtual hands rather than another avatar’s hands or a salient familiar-sized object. While these studies provide support for a body-based approach to the scaling of the spatial layout, they also demonstrate the influence of virtual bodies on perception of virtual environments. PMID:23874681
Digital evaluation of sitting posture comfort in human-vehicle system under Industry 4.0 framework
NASA Astrophysics Data System (ADS)
Tao, Qing; Kang, Jinsheng; Sun, Wenlei; Li, Zhaobo; Huo, Xiao
2016-09-01
Most of the previous studies on the vibration ride comfort of the human-vehicle system were focused only on one or two aspects of the investigation. A hybrid approach which integrates all kinds of investigation methods in real environment and virtual environment is described. The real experimental environment includes the WBV(whole body vibration) test, questionnaires for human subjective sensation and motion capture. The virtual experimental environment includes the theoretical calculation on simplified 5-DOF human body vibration model, the vibration simulation and analysis within ADAMS/VibrationTM module, and the digital human biomechanics and occupational health analysis in Jack software. While the real experimental environment provides realistic and accurate test results, it also serves as core and validation for the virtual experimental environment. The virtual experimental environment takes full advantages of current available vibration simulation and digital human modelling software, and makes it possible to evaluate the sitting posture comfort in a human-vehicle system with various human anthropometric parameters. How this digital evaluation system for car seat comfort design is fitted in the Industry 4.0 framework is also proposed.
The role of cognitive apprenticeship in learning science in a virtual world
NASA Astrophysics Data System (ADS)
Ramdass, Darshanand
2012-12-01
This article extends the discussion started by Margaret Beier, Leslie Miller, and Shu Wang's (2012) paper, Science games and the development of possible selves. In this paper, I suggest that a theoretical framework based on a sociocultural theory of learning is critical in learning in a virtual environment. I will discuss relevant research on the application of various components of the sociocultural perspective of learning in classroom environments and the potential for applying them in virtual worlds. I propose that research in science education should explore the processes underlying cognitive apprenticeship and determine how these processes can be used in virtual environments to help students learn science successfully.
The Effects of Virtual Weather on Presence
NASA Astrophysics Data System (ADS)
Wissmath, Bartholomäus; Weibel, David; Mast, Fred W.
In modern societies people tend to spend more time in front of computer screens than outdoors. Along with an increasing degree of realism displayed in digital environments, simulated weather appears more and more realistic and more often implemented in digital environments. Research has found that the actual weather influences behavior and mood. In this paper we experimentally examine the effects of virtual weather on the sense of presence. Thereby we found individuals (N=30) to immerse deeper in digital environments displaying fair weather conditions than in environments displaying bad weather. We also investigate whether virtual weather can influence behavior. The possible implications of theses findings for presence theory as well as digital environment designers will be discussed.
ERIC Educational Resources Information Center
Chihak, Benjamin J.; Plumert, Jodie M.; Ziemer, Christine J.; Babu, Sabarish; Grechkin, Timofey; Cremer, James F.; Kearney, Joseph K.
2010-01-01
Two experiments examined how 10- and 12-year-old children and adults intercept moving gaps while bicycling in an immersive virtual environment. Participants rode an actual bicycle along a virtual roadway. At 12 test intersections, participants attempted to pass through a gap between 2 moving, car-sized blocks without stopping. The blocks were…
Advanced Collaborative Environments Supporting Systems Integration and Design
2003-03-01
concurrently view a virtual system or product model while maintaining natural, human communication . These virtual systems operate within a computer-generated...These environments allow multiple individuals to concurrently view a virtual system or product model while simultaneously maintaining natural, human ... communication . As a result, TARDEC researchers and system developers are using this advanced high-end visualization technology to develop future
ERIC Educational Resources Information Center
Ryan, Jenna; Porter, Marjorie; Miller, Rebecca
2010-01-01
Current literature on libraries is abundant with articles about the uses and the potential of new interactive communication technology, including Web 2.0 tools. Recently, the advent and use of virtual worlds have received top billing in these works. Many library institutions are exploring these virtual environments; this exploration and the…
Virtual Worlds; Real Learning: Design Principles for Engaging Immersive Environments
NASA Technical Reports Server (NTRS)
Wu (u. Sjarpm)
2012-01-01
The EMDT master's program at Full Sail University embarked on a small project to use a virtual environment to teach graduate students. The property used for this project has evolved our several iterations and has yielded some basic design principles and pedagogy for virtual spaces. As a result, students are emerging from the program with a better grasp of future possibilities.
E-Learning in Chemistry Education: Self-Regulated Learning in a Virtual Classroom
ERIC Educational Resources Information Center
Eidelman, Rachel Rosanne; Shwartz, Yael
2016-01-01
The virtual Chemistry classroom is a learning environment for students that are willing to study Chemistry, but have no opportunity to do so at school. The program launched in 2015, and currently, there are 22 students in the 11th grade and 80 students in the 10th grade. This study investigates and characterizes the virtual learning environment,…
Game-Like Language Learning in 3-D Virtual Environments
ERIC Educational Resources Information Center
Berns, Anke; Gonzalez-Pardo, Antonio; Camacho, David
2013-01-01
This paper presents our recent experiences with the design of game-like applications in 3-D virtual environments as well as its impact on student motivation and learning. Therefore our paper starts with a brief analysis of the motivational aspects of videogames and virtual worlds (VWs). We then go on to explore the possible benefits of both in the…
NASA Technical Reports Server (NTRS)
Ross, M. D.; Montgomery, K.; Linton, S.; Cheng, R.; Smith, J.
1998-01-01
This report describes the three-dimensional imaging and virtual environment technologies developed in NASA's Biocomputation Center for scientific purposes that have now led to applications in the field of medicine. A major goal is to develop a virtual environment surgery workbench for planning complex craniofacial and breast reconstructive surgery, and for training surgeons.
ERIC Educational Resources Information Center
Lorenzo, Gonzalo; Pomares, Jorge; Lledo, Asuncion
2013-01-01
This paper presents the use of immersive virtual reality systems in the educational intervention with Asperger students. The starting points of this study are features of these students' cognitive style that requires an explicit teaching style supported by visual aids and highly structured environments. The proposed immersive virtual reality…
Constructing Virtual Training Demonstrations
2008-12-01
virtual environments have been shown to be effective for training, and distributed game -based architectures contribute an added benefit of wide...investigation of how a demonstration authoring toolset can be constructed from existing virtual training environments using 3-D multiplayer gaming ...intelligent agents project to create AI middleware for simulations and videogames . The result was SimBionic®, which enables users to graphically author
NASA Astrophysics Data System (ADS)
Rebolledo-Vieyra, M.; Ravelo-Cervantes, J. I.; Lecossec, A.
2007-12-01
This study reports initial results of combined Time Domain Electromagnetic (TDEM) and vertical electrical sounding (VES), geophysical characterization of the Quintana Roo coastal aquifer, with the aim of establishing effective protocols for subsequent surveys in the area, through the association of TDEM and VES. The high resistivity of the carbonate terrain, combined with the very low resistivity range of fresh-water and sea-water, are ideal to use both tools in combination. The results show that both methods used in a combination may provide a useful tool for hydrogeologial studies. In this survey we were able to identifiy a fracture 100 m x 40 m, that was correlated to fresh-water discharges in to the Puerto Morelos Reef lagoon.
Mazur, Allan; Booth, Alan
2014-02-01
The Vietnam Experience Study (VES) of 4462 male U.S. Army veterans is the first large dataset used to demonstrate that testosterone (but not cortisol) is correlated with diverse measures of antisocial, aggressive or dominant behavior. Many subsequent studies have sustained these relationships while also pointing to important caveats. Some researchers suggest that testosterone is correlated to dominance and aggression only (or mostly) in people with low cortisol, not in those with high cortisol. Here we look back to the VES to test this "dual hormone" hypothesis. We find no testosterone-cortisol interaction for seven measures of antisocial deviance. We consider scope conditions under which the dual hormone hypothesis may be valid. Copyright © 2013 Elsevier B.V. All rights reserved.
Crushing virtual cigarettes reduces tobacco addiction and treatment discontinuation.
Girard, Benoit; Turcotte, Vincent; Bouchard, Stéphane; Girard, Bruno
2009-10-01
Pilot studies revealed promising results regarding crushing virtual cigarettes to reduce tobacco addiction. In this study, 91 regular smokers were randomly assigned to two treatment conditions that differ only by the action performed in the virtual environment: crushing virtual cigarettes or grasping virtual balls. All participants also received minimal psychosocial support from nurses during each of 12 visits to the clinic. An affordable virtual reality system was used (eMagin HMD) with a virtual environment created by modifying a 3D game. Results revealed that crushing virtual cigarettes during 4 weekly sessions led to a statistically significant reduction in nicotine addiction (assessed with the Fagerström test), abstinence rate (confirmed with exhaled carbon monoxide), and drop-out rate from the 12-week psychosocial minimal-support treatment program. Increased retention in the program is discussed as a potential explanation for treatment success, and hypotheses are raised about self-efficacy, motivation, and learning.
Virtual Labs and Virtual Worlds
NASA Astrophysics Data System (ADS)
Boehler, Ted
2006-12-01
Virtual Labs and Virtual Worlds Coastline Community College has under development several virtual lab simulations and activities that range from biology, to language labs, to virtual discussion environments. Imagine a virtual world that students enter online, by logging onto their computer from home or anywhere they have web access. Upon entering this world they select a personalized identity represented by a digitized character (avatar) that can freely move about, interact with the environment, and communicate with other characters. In these virtual worlds, buildings, gathering places, conference rooms, labs, science rooms, and a variety of other “real world” elements are evident. When characters move about and encounter other people (players) they may freely communicate. They can examine things, manipulate objects, read signs, watch video clips, hear sounds, and jump to other locations. Goals of critical thinking, social interaction, peer collaboration, group support, and enhanced learning can be achieved in surprising new ways with this innovative approach to peer-to-peer communication in a virtual discussion world. In this presentation, short demos will be given of several online learning environments including a virtual biology lab, a marine science module, a Spanish lab, and a virtual discussion world. Coastline College has been a leader in the development of distance learning and media-based education for nearly 30 years and currently offers courses through PDA, Internet, DVD, CD-ROM, TV, and Videoconferencing technologies. Its distance learning program serves over 20,000 students every year. sponsor Jerry Meisner
A model for flexible tools used in minimally invasive medical virtual environments.
Soler, Francisco; Luzon, M Victoria; Pop, Serban R; Hughes, Chris J; John, Nigel W; Torres, Juan Carlos
2011-01-01
Within the limits of current technology, many applications of a virtual environment will trade-off accuracy for speed. This is not an acceptable compromise in a medical training application where both are essential. Efficient algorithms must therefore be developed. The purpose of this project is the development and validation of a novel physics-based real time tool manipulation model, which is easy to integrate into any medical virtual environment that requires support for the insertion of long flexible tools into complex geometries. This encompasses medical specialities such as vascular interventional radiology, endoscopy, and laparoscopy, where training, prototyping of new instruments/tools and mission rehearsal can all be facilitated by using an immersive medical virtual environment. Our model recognises and uses accurately patient specific data and adapts to the geometrical complexity of the vessel in real time.
SmallTool - a toolkit for realizing shared virtual environments on the Internet
NASA Astrophysics Data System (ADS)
Broll, Wolfgang
1998-09-01
With increasing graphics capabilities of computers and higher network communication speed, networked virtual environments have become available to a large number of people. While the virtual reality modelling language (VRML) provides users with the ability to exchange 3D data, there is still a lack of appropriate support to realize large-scale multi-user applications on the Internet. In this paper we will present SmallTool, a toolkit to support shared virtual environments on the Internet. The toolkit consists of a VRML-based parsing and rendering library, a device library, and a network library. This paper will focus on the networking architecture, provided by the network library - the distributed worlds transfer and communication protocol (DWTP). DWTP provides an application-independent network architecture to support large-scale multi-user environments on the Internet.
Evaluation of glucose controllers in virtual environment: methodology and sample application.
Chassin, Ludovic J; Wilinska, Malgorzata E; Hovorka, Roman
2004-11-01
Adaptive systems to deliver medical treatment in humans are safety-critical systems and require particular care in both the testing and the evaluation phase, which are time-consuming, costly, and confounded by ethical issues. The objective of the present work is to develop a methodology to test glucose controllers of an artificial pancreas in a simulated (virtual) environment. A virtual environment comprising a model of the carbohydrate metabolism and models of the insulin pump and the glucose sensor is employed to simulate individual glucose excursions in subjects with type 1 diabetes. The performance of the control algorithm within the virtual environment is evaluated by considering treatment and operational scenarios. The developed methodology includes two dimensions: testing in relation to specific life style conditions, i.e. fasting, post-prandial, and life style (metabolic) disturbances; and testing in relation to various operating conditions, i.e. expected operating conditions, adverse operating conditions, and system failure. We define safety and efficacy criteria and describe the measures to be taken prior to clinical testing. The use of the methodology is exemplified by tuning and evaluating a model predictive glucose controller being developed for a wearable artificial pancreas focused on fasting conditions. Our methodology to test glucose controllers in a virtual environment is instrumental in anticipating the results of real clinical tests for different physiological conditions and for different operating conditions. The thorough testing in the virtual environment reduces costs and speeds up the development process.
Functional performance comparison between real and virtual tasks in older adults
Bezerra, Ítalla Maria Pinheiro; Crocetta, Tânia Brusque; Massetti, Thais; da Silva, Talita Dias; Guarnieri, Regiani; Meira, Cassio de Miranda; Arab, Claudia; de Abreu, Luiz Carlos; de Araujo, Luciano Vieira; Monteiro, Carlos Bandeira de Mello
2018-01-01
Abstract Introduction: Ageing is usually accompanied by deterioration of physical abilities, such as muscular strength, sensory sensitivity, and functional capacity, making chronic diseases, and the well-being of older adults new challenges to global public health. Objective: The purpose of this study was to evaluate whether a task practiced in a virtual environment could promote better performance and enable transfer to the same task in a real environment. Method: The study evaluated 65 older adults of both genders, aged 60 to 82 years (M = 69.6, SD = 6.3). A timing coincident task was applied to measure the perceptual-motor ability to perform a motor response. The participants were divided into 2 groups: started in a real interface and started in a virtual interface. Results: All subjects improved their performance during the practice, but improvement was not observed for the real interface, as the participants were near maximum performance from the beginning of the task. However, there was no transfer of performance from the virtual to real environment or vice versa. Conclusions: The virtual environment was shown to provide improvement of performance with a short-term motor learning protocol in a timing coincident task. This result suggests that the practice of tasks in a virtual environment seems to be a promising tool for the assessment and training of healthy older adults, even though there was no transfer of performance to a real environment. Trial registration: ISRCTN02960165. Registered 8 November 2016. PMID:29369177
Immersive Virtual Moon Scene System Based on Panoramic Camera Data of Chang'E-3
NASA Astrophysics Data System (ADS)
Gao, X.; Liu, J.; Mu, L.; Yan, W.; Zeng, X.; Zhang, X.; Li, C.
2014-12-01
The system "Immersive Virtual Moon Scene" is used to show the virtual environment of Moon surface in immersive environment. Utilizing stereo 360-degree imagery from panoramic camera of Yutu rover, the system enables the operator to visualize the terrain and the celestial background from the rover's point of view in 3D. To avoid image distortion, stereo 360-degree panorama stitched by 112 images is projected onto inside surface of sphere according to panorama orientation coordinates and camera parameters to build the virtual scene. Stars can be seen from the Moon at any time. So we render the sun, planets and stars according to time and rover's location based on Hipparcos catalogue as the background on the sphere. Immersing in the stereo virtual environment created by this imaged-based rendering technique, the operator can zoom, pan to interact with the virtual Moon scene and mark interesting objects. Hardware of the immersive virtual Moon system is made up of four high lumen projectors and a huge curve screen which is 31 meters long and 5.5 meters high. This system which take all panoramic camera data available and use it to create an immersive environment, enable operator to interact with the environment and mark interesting objects contributed heavily to establishment of science mission goals in Chang'E-3 mission. After Chang'E-3 mission, the lab with this system will be open to public. Besides this application, Moon terrain stereo animations based on Chang'E-1 and Chang'E-2 data will be showed to public on the huge screen in the lab. Based on the data of lunar exploration,we will made more immersive virtual moon scenes and animations to help the public understand more about the Moon in the future.
Utilizing Virtual and Personal Learning Environments for Optimal Learning
ERIC Educational Resources Information Center
Terry, Krista, Ed.; Cheney, Amy, Ed.
2016-01-01
The integration of emerging technologies in higher education presents a new set of challenges and opportunities for educators. With a growing need for customized lesson plans in online education, educators are rethinking the design and development of their learning environments. "Utilizing Virtual and Personal Learning Environments for…
Bringing the Real World in: Reflection on Building a Virtual Learning Environment
ERIC Educational Resources Information Center
Mundkur, Anuradha; Ellickson, Cara
2012-01-01
We reflect on translating participatory and experiential learning methodologies into an online teaching environment through a Virtual Learning Environment (VLE) that simulates the "real-world" contexts of international development in order to develop an applied critical understanding of gender analysis and gender mainstreaming. Rather than being…
Offering a Framework for Value Co-Creation in Virtual Academic Learning Environments
ERIC Educational Resources Information Center
Ranjbarfard, Mina; Heidari Sureshjani, Mahboobeh
2018-01-01
Purpose: This research aims to convert the traditional teacher-student models, in which teachers determine the learning resources, into a flexible structure and an active learning environment so that students can participate in the educational processes and value co-creation in virtual academic learning environments (VALEs).…
Virtual Reality Training Environments: Contexts and Concerns.
ERIC Educational Resources Information Center
Harmon, Stephen W.; Kenney, Patrick J.
1994-01-01
Discusses the contexts where virtual reality (VR) training environments might be appropriate; examines the advantages and disadvantages of VR as a training technology; and presents a case study of a VR training environment used at the NASA Johnson Space Center in preparation for the repair of the Hubble Space Telescope. (AEF)
ERIC Educational Resources Information Center
Zhong, Ying
2013-01-01
Virtual worlds are well-suited for building virtual laboratories for educational purposes to complement hands-on physical laboratories. However, educators may face technical challenges because developing virtual worlds requires skills in programming and 3D design. Current virtual world building tools are developed for users who have programming…
The effect on lower spine muscle activation of walking on a narrow beam in virtual reality.
Antley, Angus; Slater, Mel
2011-02-01
To what extent do people behave in immersive virtual environments as they would in similar situations in a physical environment? There are many ways to address this question, ranging from questionnaires, behavioral studies, and the use of physiological measures. Here, we compare the onsets of muscle activity using surface electromyography (EMG) while participants were walking under three different conditions: on a normal floor surface, on a narrow ribbon along the floor, and on a narrow platform raised off the floor. The same situation was rendered in an immersive virtual environment (IVE) Cave-like system, and 12 participants did the three types of walking in a counter-balanced within-groups design. The mean number of EMG activity onsets per unit time followed the same pattern in the virtual environment as in the physical environment-significantly higher for walking on the platform compared to walking on the floor. Even though participants knew that they were in fact really walking at floor level in the virtual environment condition, the visual illusion of walking on a raised platform was sufficient to influence their behavior in a measurable way. This opens up the door for this technique to be used in gait and posture related scenarios including rehabilitation.
Designing a successful HMD-based experience
NASA Technical Reports Server (NTRS)
Pierce, J. S.; Pausch, R.; Sturgill, C. B.; Christiansen, K. D.; Kaiser, M. K. (Principal Investigator)
1999-01-01
For entertainment applications, a successful virtual experience based on a head-mounted display (HMD) needs to overcome some or all of the following problems: entering a virtual world is a jarring experience, people do not naturally turn their heads or talk to each other while wearing an HMD, putting on the equipment is hard, and people do not realize when the experience is over. In the Electric Garden at SIGGRAPH 97, we presented the Mad Hatter's Tea Party, a shared virtual environment experienced by more than 1,500 SIGGRAPH attendees. We addressed these HMD-related problems with a combination of back story, see-through HMDs, virtual characters, continuity of real and virtual objects, and the layout of the physical and virtual environments.
NASA Technical Reports Server (NTRS)
Lindsey, Patricia F.
1993-01-01
In its search for higher level computer interfaces and more realistic electronic simulations for measurement and spatial analysis in human factors design, NASA at MSFC is evaluating the functionality of virtual reality (VR) technology. Virtual reality simulation generates a three dimensional environment in which the participant appears to be enveloped. It is a type of interactive simulation in which humans are not only involved, but included. Virtual reality technology is still in the experimental phase, but it appears to be the next logical step after computer aided three-dimensional animation in transferring the viewer from a passive to an active role in experiencing and evaluating an environment. There is great potential for using this new technology when designing environments for more successful interaction, both with the environment and with another participant in a remote location. At the University of North Carolina, a VR simulation of a the planned Sitterson Hall, revealed a flaw in the building's design that had not been observed during examination of the more traditional building plan simulation methods on paper and on computer aided design (CAD) work station. The virtual environment enables multiple participants in remote locations to come together and interact with one another and with the environment. Each participant is capable of seeing herself and the other participants and of interacting with them within the simulated environment.
The NASA Augmented/Virtual Reality Lab: The State of the Art at KSC
NASA Technical Reports Server (NTRS)
Little, William
2017-01-01
The NASA Augmented Virtual Reality (AVR) Lab at Kennedy Space Center is dedicated to the investigation of Augmented Reality (AR) and Virtual Reality (VR) technologies, with the goal of determining potential uses of these technologies as human-computer interaction (HCI) devices in an aerospace engineering context. Begun in 2012, the AVR Lab has concentrated on commercially available AR and VR devices that are gaining in popularity and use in a number of fields such as gaming, training, and telepresence. We are working with such devices as the Microsoft Kinect, the Oculus Rift, the Leap Motion, the HTC Vive, motion capture systems, and the Microsoft Hololens. The focus of our work has been on human interaction with the virtual environment, which in turn acts as a communications bridge to remote physical devices and environments which the operator cannot or should not control or experience directly. Particularly in reference to dealing with spacecraft and the oftentimes hazardous environments they inhabit, it is our hope that AR and VR technologies can be utilized to increase human safety and mission success by physically removing humans from those hazardous environments while virtually putting them right in the middle of those environments.
Employing immersive virtual environments for innovative experiments in health care communication.
Persky, Susan
2011-03-01
This report reviews the literature for studies that employ immersive virtual environment technology methods to conduct experimental studies in health care communication. Advantages and challenges of using these tools for research in this area are also discussed. A literature search was conducted using the Scopus database. Results were hand searched to identify the body of studies, conducted since 1995, that are related to the report objective. The review identified four relevant studies that stem from two unique projects. One project focused on the impact of a clinician's characteristics and behavior on health care communication, the other focused on the characteristics of the patient. Both projects illustrate key methodological advantages conferred by immersive virtual environments, including, ability to maintain simultaneously high experimental control and realism, ability to manipulate variables in new ways, and unique behavioral measurement opportunities. Though implementation challenges exist for immersive virtual environment-based research methods, given the technology's unique capabilities, benefits can outweigh the costs in many instances. Immersive virtual environments may therefore prove an important addition to the array of tools available for advancing our understanding of communication in health care. Published by Elsevier Ireland Ltd.
VERS: a virtual environment for reconstructive surgery planning
NASA Astrophysics Data System (ADS)
Montgomery, Kevin N.
1997-05-01
The virtual environment for reconstructive surgery (VERS) project at the NASA Ames Biocomputation Center is applying virtual reality technology to aid surgeons in planning surgeries. We are working with a craniofacial surgeon at Stanford to assemble and visualize the bone structure of patients requiring reconstructive surgery either through developmental abnormalities or trauma. This project is an extension of our previous work in 3D reconstruction, mesh generation, and immersive visualization. The current VR system, consisting of an SGI Onyx RE2, FakeSpace BOOM and ImmersiveWorkbench, Virtual Technologies CyberGlove and Ascension Technologies tracker, is currently in development and has already been used to visualize defects preoperatively. In the near future it will be used to more fully plan the surgery and compute the projected result to soft tissue structure. This paper presents the work in progress and details the production of a high-performance, collaborative, and networked virtual environment.
Two-photon calcium imaging during fictive navigation in virtual environments
Ahrens, Misha B.; Huang, Kuo Hua; Narayan, Sujatha; Mensh, Brett D.; Engert, Florian
2013-01-01
A full understanding of nervous system function requires recording from large populations of neurons during naturalistic behaviors. Here we enable paralyzed larval zebrafish to fictively navigate two-dimensional virtual environments while we record optically from many neurons with two-photon imaging. Electrical recordings from motor nerves in the tail are decoded into intended forward swims and turns, which are used to update a virtual environment displayed underneath the fish. Several behavioral features—such as turning responses to whole-field motion and dark avoidance—are well-replicated in this virtual setting. We readily observed neuronal populations in the hindbrain with laterally selective responses that correlated with right or left optomotor behavior. We also observed neurons in the habenula, pallium, and midbrain with response properties specific to environmental features. Beyond single-cell correlations, the classification of network activity in such virtual settings promises to reveal principles of brainwide neural dynamics during behavior. PMID:23761738
Monteiro, Alexandra M V; Corrêa, Diogo Goulart; Santos, Alair Augusto Sarmet M D; Cavalcanti, Silvio A; Sakuno, Telma; Filgueiras, Tereza; Just, Eduardo; Santos, Munique; Messina, Luiz Ary; Haddad, Ana Estela; Marchiori, Edson
2011-12-01
To report the experience of the Brazilian Program of Pediatric Teleradiology in combining teleconferencing and a virtual learning environment for services integration, collaborative research, and continuing education in pediatric radiology. We performed virtual meetings from March 2005 to October 2010 on pediatric radiology-related themes, using a combination of videoconferences and Web conferences, which were recorded and made available in an open-source software (Moodle) for reuse. We performed 58 virtual sessions: 29 anatomical-clinical-radiological sessions, 28 on upgrading themes, and 1 virtual symposium. The average of connected points was 12 by videoconference and 39 by Web conference, and of 450 participants per event. At the time of this writing, 318 physicians and students are registered in the virtual learning environment, with a total of 14,678 accesses. Telemedicine is being included in pediatric radiology practice, as a means for distance education, training, and continuing integration between groups.
Two-photon calcium imaging during fictive navigation in virtual environments.
Ahrens, Misha B; Huang, Kuo Hua; Narayan, Sujatha; Mensh, Brett D; Engert, Florian
2013-01-01
A full understanding of nervous system function requires recording from large populations of neurons during naturalistic behaviors. Here we enable paralyzed larval zebrafish to fictively navigate two-dimensional virtual environments while we record optically from many neurons with two-photon imaging. Electrical recordings from motor nerves in the tail are decoded into intended forward swims and turns, which are used to update a virtual environment displayed underneath the fish. Several behavioral features-such as turning responses to whole-field motion and dark avoidance-are well-replicated in this virtual setting. We readily observed neuronal populations in the hindbrain with laterally selective responses that correlated with right or left optomotor behavior. We also observed neurons in the habenula, pallium, and midbrain with response properties specific to environmental features. Beyond single-cell correlations, the classification of network activity in such virtual settings promises to reveal principles of brainwide neural dynamics during behavior.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Imura, K; Fujibuchi, T; Hirata, H
Purpose: Patient set-up skills in radiotherapy treatment room have a great influence on treatment effect for image guided radiotherapy. In this study, we have developed the training system for improving practical set-up skills considering rotational correction in the virtual environment away from the pressure of actual treatment room by using three-dimensional computer graphic (3DCG) engine. Methods: The treatment room for external beam radiotherapy was reproduced in the virtual environment by using 3DCG engine (Unity). The viewpoints to perform patient set-up in the virtual treatment room were arranged in both sides of the virtual operable treatment couch to assume actual performancemore » by two clinical staffs. The position errors to mechanical isocenter considering alignment between skin marker and laser on the virtual patient model were displayed by utilizing numerical values expressed in SI units and the directions of arrow marks. The rotational errors calculated with a point on the virtual body axis as the center of each rotation axis for the virtual environment were corrected by adjusting rotational position of the body phantom wound the belt with gyroscope preparing on table in a real space. These rotational errors were evaluated by describing vector outer product operations and trigonometric functions in the script for patient set-up technique. Results: The viewpoints in the virtual environment allowed individual user to visually recognize the position discrepancy to mechanical isocenter until eliminating the positional errors of several millimeters. The rotational errors between the two points calculated with the center point could be efficiently corrected to display the minimum technique mathematically by utilizing the script. Conclusion: By utilizing the script to correct the rotational errors as well as accurate positional recognition for patient set-up technique, the training system developed for improving patient set-up skills enabled individual user to indicate efficient positional correction methods easily.« less
ERIC Educational Resources Information Center
Reid, Denise
2005-01-01
The Pediatric Volitional Questionnaire (PVQ) was used along with the Test of Playfulness (TOP) to assess 16 children with cerebral palsy who took part in a study of virtual reality play intervention. Both observational measures are designed to assess children as they are engaged in occupations in one or more environments. Virtual reality offers an…
ERIC Educational Resources Information Center
López Gavira, Rosario; Omoteso, Kamil
2013-01-01
As the power of the virtual world continues to manifest itself in people's quality of life and capabilities (including learning), this paper aims to assess accounting students' perceptions of the usefulness of Virtual Learning Environments (VLE) to their learning experiences. It also considers the factors that may influence students' preferences…
ERIC Educational Resources Information Center
Merchant, Zahira; Goetz, Ernest T.; Keeney-Kennicutt, Wendy; Kwok, Oi-man; Cifuentes, Lauren; Davis, Trina J.
2012-01-01
We examined a model of the impact of a 3D desktop virtual reality environment on the learner characteristics (i.e. perceptual and psychological variables) that can enhance chemistry-related learning achievements in an introductory college chemistry class. The relationships between the 3D virtual reality features and the chemistry learning test as…
3D Technology Selection for a Virtual Learning Environment by Blending ISO 9126 Standard and AHP
ERIC Educational Resources Information Center
Cetin, Aydin; Guler, Inan
2011-01-01
Web3D presents many opportunities for learners in a virtual world or virtual environment over the web. This is a great opportunity for open-distance education institutions to benefit from web3d technologies to create courses with interactive 3d materials. There are many open source and commercial products offering 3d technologies over the web…