Collaborative learning in multi-user virtual environments

Multi-user virtual environments (MUVEs) have captured the attention and interest of educators as remote collaborative learning environments due to their immersion, interaction and communication capabilities. However, productive learning interactions cannot be considered a given and careful consideration of the design of learning activities and organizational support must be provided to foster collaboration. In this paper, a model to support collaborative learning in MUVEs is presented. This model enables the scaffolding of learning workflows and organizes collaborative learning activities by regulating interactions. Software architecture is developed to support the model, and to deploy and enact collaborative learning modules. A user-centered design has been followed to identify successful strategies for modeling collaborative learning activities in a case study. The results show how interactions with elements of 3D virtual worlds can enforce collaboration in MUVEs.     

Natural perception in dynamic stereoscopic augmented reality environments

Notwithstanding the recent diffusion of the stereoscopic 3D technologies for the development of powerful human computer interaction systems based on augmented reality environment, with the conventional approaches an observer freely moving in front of a 3D display could experience a misperception of the depth and of the shape of virtual objects. Such distortions can cause eye fatigue and stress for entertainment applications, and they can have serious consequences in scientific and medical fields, where a veridical perception of the scene layout is required. We propose a novel technique to obtain augmented reality systems capable to correctly render 3D virtual objects to an observer that changes his/her position in the real world and acts in the virtual scenario. By tracking the positions of the observer’s eyes, the proposed technique generates the correct virtual view points through asymmetric frustums, thus obtaining the correct left and right projections on the screen. The natural perception of the scene layout is assessed through three experimental sessions with several observers.     

Factors that affect depth perception in stereoscopic displays.

This study investigated several factors that affect depth perception in stereoscopic displays: half-image separation magnitude, separation direction (crossed vs. uncrossed), viewing distance, stimulus size, and exposure duration. The depth perceived under various combinations of levels of these factors was compared with depth predicted by the geometry of stereopsis. Perceived depth in the crossed-separation direction was frequently close to predictions, such that increases in separation and viewing distance produced appropriate increases in perceived depth. Depth in the uncrossed direction was frequently less than that predicted, especially for small stimuli presented at a long viewing distance, with a large half-image separation, and/or with a brief duration. Thus depth in both crossed and uncrossed directions equaled predictions only for large stimuli exposed for a long duration.     

Exploring embedded guidance and self-efficacy in educational multi-user virtual environments

In this paper, we present the results of an exploratory study into the relationship between student self-efficacy and guidance use in a Multi-User Virtual Environment (MUVE) science curriculum project. We describe findings from a sample of middle school science students on the combined impact on learning of student self-efficacy in scientific inquiry and use of individualized guidance messages, and on the interplay between levels of self-efficacy and use of an embedded guidance system in an educational MUVE. Results from our study showed that embedded guidance was associated with improved learning outcomes for learners across a spectrum of self-reported efficacy in science. However, we also found that learners with low levels of initial self-efficacy in science viewed fewer guidance messages than their higher efficacy peers, and did not perform as well as their higher efficacy peers regardless of guidance use level. At the same time, outcomes for low self-efficacy students who used the guidance system heavily were raised to the level of high self-efficacy students who did not use the system.     

Creating genetic applications for informal science learning in multi-user virtual environments

A team of developers at the Cornell Theory Center (CTC), Cornell University's high-performance computing and interdisciplinary research center, has implemented a 3D multi-user virtual science museum, SciCentr. SciCentr is a virtual world based on Active Worlds client/server technology. Related to gaming technology, and thus attractive to youth, virtual environments can be applied to formal and informal science education in areas such as genetics, as well as to language learning and social studies. In this paper, we review the current state of our understanding of the impact of this technology on informal science learning. We attempt to identify some of the advantages of using this technology, design features of our implementation, and ideas for managing the social interaction among educational users. More specifically, we will discuss pilot user experiences focused on crop genetics in SciCentr's Plant Breeding Beds and on the related SciFair exhibits, both examples of collaborative experiences in our virtual worlds. Finally, we describe the next stage in interactive interface development for our Gene Bot feature.     

Fast and high-quality virtual view synthesis from multi-view plus depth videos

Multimedia Tools and Applications - Depth image based rendering (DIBR) is an effective method for virtual view synthesis from Multi-view Plus Depth(MVD) video. Synthetic images, however, often...     

Towards perceptual fidelity: Slant perception in real and interactive virtual environments

An innovative motoric measure of slant based on gait is proposed as the angle between the foot and the walking surface during walking. This work investigates whether the proposed action-based measure is affected by factors such as material and inclination of the walking surface. Experimental studies were conducted in a real environment set-up and in its virtual simulation counterpart evaluating behavioural fidelity and user performance in ecologically-valid simulations. In the real environment, the measure slightly overestimated the inclined path whereas in the virtual environment it slightly underestimated the inclined path. The results imply that the proposed slant measure is modulated by motoric caution. Since the “reality” of the synthetic environment was relatively high, performance results should have revealed the same degree of caution as in the real world, however, that was not the case. People become more cautious when the ground plane was steep, slippery, or virtual.     

Storytelling in virtual environments from a virtual guide perspective

This paper describes our proposal for storytelling in virtual environments from a virtual guide perspective, detailing the involved knowledge representation and algorithms. In our model the guide begins at a particular location and starts to navigate the world telling the user stories related to the places she visits. Our guide tries to emulate a real guides behaviour in such a situation. In particular, she behaves as a spontaneous real guide who knows stories about the places in the virtual world but has not prepared an exhaustive tour nor a storyline.     

Three views of virtual reality: virtual environments in the USmilitary

A virtual environment is a generic, relatively low-cost real-time interactive simulation. It is shown that the US military has been a primary supporter of real-time simulation for more than 60 years, ever since the development of the Link Flight Instrument Trainer in the late 1930s. The development of flight simulation systems and head-mounted displays are reviewed. The use of virtual environments for team training, battlefield review and tactics development is discussed. Several research projects involving virtual environments and military applications are described     

Scape: supporting stereoscopic collaboration in augmented and projective environments

Our collaborative augmented reality system for multiple users simultaneously creates outside-in workbench views and inside-out life-size walkthrough views, bridging the virtual and augmented reality paradigms. Here we introduce a collaborative infrastructure - stereoscopic collaboration in augmented and projective environments(Scape). Scape seamlessly merges the paradigm of virtual reality with that of augmented reality in a single system and provides multimodality interface devices and unique widget interfaces to facilitate collaborative work in 3D environments. A custom-designed cross-platform application-programming interface (API) allows high and medium-level controls over the Scape workspace to enable augmented interaction and collaboration.     

The influence of the availability of visual cues on the accurate perception of spatial dimensions in architectural virtual environments

Several authors have observed that spatial dimensions tend to be underestimated in virtual environments. In this study, we hypothesize that the availability of visual cues in virtual environments has an influence on the accuracy of perception. An experiment was conducted to compare spatial perception in real and virtual environments that were modeled differently and visualized using a head-mounted display. Results suggest that the greater the availability of visual cues, the greater the level of accuracy in the estimates, especially for egocentric dimensions (p < 0.001). In the end, this study contributes to a better understanding of how architectural virtual environments should be modeled for use in professional or commercial applications where accurate and reliable simulations are required.     

Human knowledge acquisition from 3D interaction in virtual environments

Recently,virtual environment (VE) based design and planning,which is a kind of interaction intensive computing,has shown great potential.Most users of such systems are specialists or technicians and their 3D interactions with the system embed a great deal of knowledge and skills.Thus,how to integrate human knowledge and skills into VE is a great challenge to researchers in the human computer interaction field.This paper proposes a method for acquiring user knowledge from VE.The main ideas and work include,abstracting the interactive process and formalizing the interactive semantics,as well as providing a semantic model of an interactive information repository,from which user interactive processes can be retrieved and all kinds of application logics can be established.A virtual assembly planning system is introduced as an example of a practical application of this method.Experiments show that the related models can well capture user knowledge and retrieve the interaction process.     

A sense of self: The role of presence in virtual environments

Several factors contribute to an individual’s experiences in computer-based environments. Previous research shows one such factor, the degree to which users feel connected to a virtual environment, influences the actions of individuals within the environment ( and ). Additional factors, such as people’s personality and the personality of their avatar, influence behaviors in virtual environments (McCreery, Krach, Schrader, & Boone, 2012). The current study focused on the role of presence as it affects behavior within the virtual environment. Presence has been defined as the psychological state where virtual experiences feel authentic. However, the degree to which presence acts as a mediating variable in virtual environments is not well understood. The current study employed a combination of survey instruments and direct observation to explore the relationships among personality of self and avatar, presence, and behaviors within a virtual environment. Findings indicated that participant scores in the domain of agreeableness were a significant predictor of agreeable behavior in the virtual environment. However, with the exception of negative effects (e.g., dizziness), presence does not appear to influence behavior. Overall implications for these findings are discussed.     

Presence: a unique characteristic in educational virtual environments

This article investigates the effect of presence on learning outcomes in educational virtual environments (EVEs) in a sample of 60 pupils aged between 11 and 13 years. We study the effect of personal presence, social presence and participant’s involvement on certain learning outcomes. We also investigate if the combination of the participant’s representation model in the virtual environment (VE) with the way it is presented gives a higher sense of presence that contributes to learning outcomes. Our results show that the existence of an avatar as the pupils’ representation enhanced presence and helped them to successfully perform their learning tasks. The pupils had a high sense of presence for both cases of the EVE presentation, projection on a wall and through a head mounted display (HMD). Our socialized virtual environment seems to play an important role in learning outcomes. The pupils had a higher sense of presence and completed their learning tasks more easily and successfully in the case of their egocentric representation model using the HMD.     

The WALKABOUT: Using virtual environments to assess large-scale spatial abilities

Computer-simulated virtual environments (VEs) offer promise for assessing people's spatial abilities in large real-world environments. This paper introduces the WALKABOUT, a VE-based test that simulates navigation through large spaces. Participants' ability to form an accurate mental representation of a familiar large-scale environment correlated nearly as highly with their performance on the WALKABOUT as it did with their self-reported sense of direction. Performance on two subscales of the test further indicated that the ability to account for changing egocentric relationships as a result of self-movement and the ability to recognize a novel perspective on an environment are both significantly related to spatial ability at the environmental scale.