3D Virtual Space Research Articles

3D Visual Activity Assessment Based on Natural Scene Statistics

One of the most challenging ongoing issues in the field of 3D visual research is how to perceptually quantify object and surface visualizations that are displayed within a virtual 3D space between a human eye and 3D display. To seek an effective method of quantification, it is necessary to measure various elements related to the perception of 3D objects at different depths. We propose a new framework for quantifying 3D visual information that we call 3D visual activity (3DVA), which utilizes natural scene statistics measured over 3D visual coordinates. We account for important aspects of 3D perception by carrying out a 3D coordinate transform reflecting the nonuniform sampling resolution of the eye and the process of stereoscopic fusion. The 3DVA utilizes the empirical distortions of wavelet coefficients to a parametric generalized Gaussian probability distribution model and a set of 3D perceptual weights. We conducted a series of simulations that demonstrate the effectiveness of the 3DVA for quantifying the statistical dynamics of visual 3D space with respect to disparity, motion, texture, and color. A successful example application is also provided, whereby 3DVA is applied to the problem of predicting visual fatigue experienced when viewing 3D displays.

Stereoscopy benefits processing of dynamic visual scenes by disambiguating object occlusions

How and to what extent stereoscopic cues help process dynamic visual scenes is still unknown. As we navigate in crowds or when we play sports we are often obliged to make rapid decisions in complex motion environments while attending to multiple elements. Stereoscopy can improve speed thresholds for a multiple object tracking (MOT) (Faubert & Sidebottom, 2012), but the nature of this advantage remains undetermined. From an attention perspective, there are at least two possible hypotheses to explain this advantage. One possibility is that stereoscopy reduces the attentional bottleneck as seen in 2-dimensional MOT environments (Intrilligator & Canavagh, 2001) by distributing attention uniformly in 3D space. Another hypothesis is that the stereoscopy helps attentional tracking by segregating the target and the non-target objects during occlusions. We have addressed these hypotheses by testing subjects with and without stereoscopic cues for different stimulus configurations in which pairs of spheres were rotating in orbit with one another in a 3D virtual space. In one set of conditions, object pairs rotated without ever occluding each other. In the second set of conditions, the objects occasionally occluded each other as they were rotating around an axis perpendicular to the observer. All conditions consisted of 4 pairs of spheres presented in each quadrant of the visual field at 20 degrees of eccentricity. Stereoscopy improved MOT speed threshold by a factor of about 3 when objects occluded each other, but slightly, yet significantly, impaired speed threshold by about 18% when objects did not occlude each other. We conclude that the overall benefit of stereoscopy for processing dynamic scenes comes from improved attention tracking by disambiguating targets from non-targets during occlusions. Conversely, stereoscopic cues were a disadvantage in absence of occlusions. Meeting abstract presented at VSS 2013

VR-Based Interactive Experienced Platform for Showroom

With the rapid development of information technology and new media technology, the introduction of the experience economy, using the new media interactive tools into industry of real estate has become a very powerful method to increase the value of estate product. The article has used virtual reality technology to design the interactive experienced platform for showroom, realized the whole architecture of the platform, and designed interactive experience of living room, bedroom, kitchen and bathroom in real time. In the platform, users can experience the one-bedroom showroom interactively and as really as possible. Finally, the article has introduced the processes and methods of building 3D model and virtual space model.

가상현실공간에서 아바타를 통한 원격학습이 아바타 사용자의 교수효능감에 미치는 영향

이 연구의 목적은 가상현실공간에서 아바타를 이용한 원격강의 경험이 사용자의 교수효능감에 미치는 영향을 알아보는 것이다. 이 연구를 위해 J대학교 교육학 전공 강좌의 수강생 9명이 연구에 참여하였다. 이들은 모두 교육학 전공의 박사과정 학생들이었다. 이 강좌의 첫 번째 강의에서 6시간 동안 세컨드라이프 사용법에 대해 면대면 강의가 이루어졌으며, 이후 3시간씩 14회의 강의는 모두 세컨드라이프 내 강의실에서 이루어졌다. 설문에 응한 5명의 참여자로부터의 성찰노트, 연구자 관찰 및 면담 내용을 분석한 결과, 세컨드라이프에서 아바타를 사용한 원격강의 수강과 발표 경험은 세컨드라이프에서 아바타를 사용한 원격 강의를 수행할 수 있는 자신감에 영향을 미친 것으로 나타났다. 이 연구는 세컨드라이프라는 가상현실공간에서 아바타를 사용한 원격교육의 가능성을 확인하였다는 것에 의의가 있으며, 향후 원격 교육에 대한 연구를 촉진할 것으로 기대된다. The purpose of this study was to investigate the influence of distance education experience using users' avatars in virtual reality space on their teaching efficacy belief. There were 9 participants who were enrolled in a course in doctoral program of education department in J University for the study. The first class of six sessions was face to face class on how to use Second Life and the 14 classes of 3 sessions were done in a classroom of Second Life. According to the analysis of reflection notes, interviews, researcher's observations of 5 participants, their experiences of presentation and taking classes in distance education using their own avatars in Second Life had positive influence on participants' teaching efficacy belief in their future working for distance education using avatars of Second Life. The implication of this study is to show some conditions for successful distance education as well as to see the potential of distance education in 3D virtual reality space using avatars. This study will contribute to promote the future study in distance education field.

The Design of Virtual Reality Flight Simulation Platform Based on Rigidbody Kinematics

MATLAB○R /Simulink○R simulation platform with man-in-the-loop was designed to realize virtual reality flight based on rigid-body kinematics. Joystick orders input by operators can be transformed into control signals. Position translation, rotation quaternion and other parameters calculated by flight motion module were sent to 3D virtual reality space. 3D virtual reality space based on VRML was designed by V-realm Builder. Joystick inputs, flight motion module and 3D virtual reality space were combined into a whole simulation system by Simulink 3D Animation Blockset. Results of simulation demonstrated that the simulation platform can realize piloting task under the control of multiple operators with good maneuverability and verisimilar visual human-computer interface when 3D flight trajectory was drawing in the 3D space at the same time.

Direct Manipulation Interface for 3D Agents Based on Stretched Word-end Voice Commands

With the recent progress in computer hardware and computer graphics (CG) techniques, applications using 3D virtual space are getting popular. So far, a mouse and a keyboard are generally used in these applications. While a mouse is a very successful input device for continuously controlling 2D objects, it is not necessarily intuitive for controlling 3D objects. In order to control 3D objects such as an avatar or a moving camera in a virtual space, speech interface has a potential to be a more natural and powerful alternative to a mouse. We propose speech based direct manipulation interface based on stretched word-end voice that controls continuous movements of 3D objects. By combining the proposed method with normal word based commands, both continuous movements and discrete actions are seamlessly controlled. Therefore, everything can be controlled using speech. The proposed method is implemented as an interface to the Second Life system. We compare it with a conventional speech based method that specifies start and end timing of motions. Analyses based on human subjects show that the proposed method is superior to the conventional speech based method. Moreover, we show that the best result is obtained when both methods are combined.

How to Apply Real Bat and BallintoVirtual Baseball Contents

It is very challenging issue to utilize human-being’s behaviours or reactions as a way of interacting to virtual world. Indoor baseball simulation system is one of good candidates to combine real equipment and actions with virtual contents. As one of experimental approach to break a barrier between virtual game space and human-being’s real behaviour, we mapped out an experiment on seamless gaming between 3D virtual game space and human-being’s real behavioural space, where real balls and bats are augmented with online baseball contents through computer vision and sensor technologies. The Simulation Engine, the key part of our proposal, consists of 6 components: Pitch Recognizer, Toss Controller, Swing Detector, Vehicle Recognizer, Vehicle Tracker and Trajectory Calculator. This approach, utilizing human-being's behaviours as input event, will open the new field of digital interfaces.

CFD를 이용한 가연성 가스의 확산 및 폭발 Simulation

현재 가연성 가스의 누출시 누출된 가스의 확산과 VCE에 의한 과압을 예측하기 위해 여러 모델들이 이용되고 있다. 그러나 이 모델들은 누출설비의 지형과 장애물 그리고 건물들의 영향에 대해서는 충분히 고려하지 않은 단순한 접근방법을 이용하고 있다. 이에 본 연구는 누출된 물질의 연소형태, 설비의 Geometry, 난류, 장애물, 바람의 영향 등 여러 변수를 고려하여 보다 정확하게 분석할 수 있는 CFD(Computational Fluid Dynamics) Model을 검토함으로서 누출된 가스의 확산과정과 분포형태 그리고 폭발시 화염과 과압의 결과를 2D와 3D의 가상공간에서 제시하였다. 이러한 CFD 분석결과는 폭발에 대한 리스크 분석과 리스크 기반의 설계에 있어 유용하게 활용될 것으로 판단된다. Various models are currently applied to predict the dispersion of leaked combustible gas and overpressure from a vapor cloud explosion(VCE). However, those models use simple approaches where topography and barriers of anti-leakage facilities and the effects of buildings were not sufficiently taken into considerations. For this reason, this study has proposed the dispersion process of leaked gas, distribution patterns, and flames and overpressure generated from gas explosions in 2D and 3D virtual spaces by reviewing more accurately analyzable computational fluid dynamics (CFD) model by considering various variables including combustion types of leaked substances, geometry of facility, warm currents, barriers, the influence of wind, and others. The CFD analysis results are anticipated to be usefully applied for the risk analysis of explosion and for the risk-based design.

Caring in the dynamics of design and languaging: exploring second language learning in 3D virtual spaces

This study provides concrete evidence of ecological, dialogical views of languaging within the dynamics of coordination and cooperation in a virtual world. Beginning level second language learners of Chinese engaged in cooperative activities designed to provide them opportunities to refine linguistic actions by way of caring for others, for the world, and for themselves. Increased target language use in highly-aligned co-ordinations was traced in the non-linear design of problem-solving spaces by looking at how meaning making and values-realizing trajectories were co-developed with semiotic resources and sociocultural material artifacts in goal-directed activities. More significantly, the non-linear design gives rise to two new problem spaces: coordinating problems and emergent problems, both of which promoted caring and individualized values-realization. Consequently, learners’ diverse identity development occurs in connection with localized values-realization and through sociohistorical experiences. Reciprocally, this development allows language learners to discover and create new affordances in coordinating their thoughts, feelings, actions, and values with others in an ongoing cycle of problem solving.

Virtual Reality Platform Based Simulation System of Environmental Noise Abatement Research

The general mathematic mode of computing noise abatement is commonly used for most project planning and appraisal of environmental noise abatement projects. However, the inconvenient and impracticable mode and algorithm usually cannot meet the real world computation and testing. Therefore, a more practicable abatement mode and algorithm (multiple noise sources with multiband under sound barriers) which had been applied to VR based simulation system. That implemented the function of real-time demonstrating noise scattering condition within 3D virtual space, furthermore, with sound barriers added in 3D scene, the effectiveness of denoise by sound barriers also can be demonstrated within this system. That provides a significant solution for environmental noise abatement projects as a whole.

W011006 釜石モデルによる津波解析・避難シミュレーションとその可視化 : バーチャルリアリティ空間の津波リスク認知モデルとしての活用

W011006 釜石モデルによる津波解析・避難シミュレーションとその可視化 : バーチャルリアリティ空間の津波リスク認知モデルとしての活用

Multi-Modal Inference in Animacy Perception for Artificial Object

Sometimes we feel animacy for artificial objects and their motion. Animals usually interact with environments through multiple sensory modalities. Here we investigated how the sensory responsiveness of artificial objects to the environment would contribute to animacy judgment for them. In a 90-s trial, observers freely viewed four objects moving in a virtual 3D space. The objects, whose position and motion were determined following Perlin-noise series, kept drifting independently in the space. Visual flashes, auditory bursts, or synchronous flashes and bursts appeared with 1–2 s intervals. The first object abruptly accelerated their motion just after visual flashes, giving an impression of responding to the flash. The second object responded to bursts. The third object responded to synchronous flashes and bursts. The forth object accelerated at a random timing independent of flashes and bursts. The observers rated how strongly they felt animacy for each object. The results showed that the object responding to the auditory bursts was rated as having weaker animacy compared to the other objects. This implies that sensory modality through which an object interacts with the environment may be a factor for animacy perception in the object and may serve as the basis of multi-modal and cross-modal inference of animacy.

Realistic perspective projections for virtual objects and environments

Computer graphics systems provide sophisticated means to render virtual 3D space to 2D display surfaces by applying planar geometric projections. In a realistic viewing condition the perspective applied for rendering should appropriately account for the viewer's location relative to the image. As a result, an observer would not be able to distinguish between a rendering of a virtual environment on a computer screen and a view “through” the screen at an identical real-world scene. Until now, little effort has been made to identify perspective projections which cause human observers to judge them to be realistic. In this article we analyze observers' awareness of perspective distortions of virtual scenes displayed on a computer screen. These distortions warp the virtual scene and make it differ significantly from how the scene would look in reality. We describe psychophysical experiments that explore the subject's ability to discriminate between different perspective projections and identify projections that most closely match an equivalent real scene. We found that the field of view used for perspective rendering should match the actual visual angle of the display to provide users with a realistic view. However, we found that slight changes of the field of view in the range of 10-20% for two classes of test environments did not cause a distorted mental image of the observed models.

Detailed visualization and morphometric analysis of reconstructed neurons using Blender and Python

Topology and functional features are two related aspects in a neuron. Understanding and measuring the neuron's topology is therefore an important step in inferring and constraining its functional properties. Unfortunately the sheer complexity of most neuron's structures makes it virtually impossible to describe the topology richness in just a handful of parameters. Ultimately, the best way to describe a neuron's topology is by plainly performing reconstruction and visualizing it in a virtual 3D space. Here we present a collection of scripts, written in python programming language, which use Blender for 3D visualization. Blender is a well established free open source 3D content creation suite, available for all major operating systems under the GNU General Public License. The main script is able to read the ASC file format from Neurolucida (MicroBrightField, Inc.), the most commonly used system for single neuron reconstruction, and parse the following structures: cell body contour, axonal trees, dendritic trees, spines and varicosities. The script offers several options for rendering each of these structures: levels of detail for each structure, type of cell body representation, level of interpolation in trees for smoother representation, which types of structures should be rendered, etc. All trees (axonal and dendritic) are created using an algorithm which produces a single mesh for each tree. The tree mesh is built in sequence, with each new raw 3D point being used to pull and grow the mesh towards the new point. Interpolation, if selected, uses cubic Bezier curves to smooth tree curvatures. The construction of the models from the raw data is very fast and trees take only a few seconds to be built and rendered, even if they are made up of several thousand 3D points. Varicosities are slower to render and a neuron with a few thousand varicosities can take several minutes to be reconstructed. The graphical user interface (GUI) for the main script and a snapshot of a reconstructed neuron visualized with the script, are shown in Figure ​Figure11. Figure 1 Rendered neuron using the visualization script. Blue and red spheres represent varicosities. The script's GUI is shown in the bottom right. In addition to the main script, a collection of python functions were created to perform measurements and calculations on the parsed neuron data. These functions are accessible through an interactive python command window and they allow, among other things, calculation of varicosities densities, fiber lengths and inter-spine distances. The scripts can easily be extended to incorporate new functions.

Effects of environmental context on temporal perception bias in apparent motion

We investigated whether the directional effect on the kappa effect can be attributed to the directional anisotropy of retinotopical space or to the representation of forces provided by environmental contexts (e.g., gravity) in an observed event. We examined whether different contexts with similar directional changes (straight vs. reversed motion) influence the kappa effect in four experiments. The object’s motion appeared to depict only forces under the natural laws of physics on a slope (Experiment 1) or on a horizontal plane (Experiment 2) in virtual 3D space. In Experiments 3 and 4, the motion appeared to be subjected to external or self-driving forces additionally influenced by internal forces on a slope (Experiment 3) or a horizontal plane (Experiment 4). The results demonstrated that the directional effect on the kappa effect was observed only in Experiment 1, and not in Experiments 2 and 3, while the kappa effect was preserved. Furthermore, not even the kappa effect was observed in the reversed motion of Experiment 4. The results of the present study suggest that the determining factor of direction in the kappa effect is not a simple anisotropy, but rather the context of observed events.

Affordances and Constraints to E-Learning: Role of Architecture in 3D Learning Space Digital Design

While abundant research has been devoted to investigate successful learning prospects of 3D Virtual Learning Environments (VLEs), sparse research explores users’ satisfaction from buildings used within these 3DVLEs. No research depicts users’ contentment levels, preferences or requirements from 3D educational buildings’ different constructional and architectural design elements. This paper is part of an ongoing research investigating the presence of such impact of architectural features of 3D virtual educational classrooms on users’ comfort within them, by recording and categorizing higher education students’ space design propositions to enhance virtual campuses, internally and externally. This has potential to boost e-learning experiences within 3DVLEs analogous to the positive effect of physical real-life architecture on students’ learning within their respective classrooms. The second part of this paper offers an example. For, while former research also reveals that architectural colour-design of physical learning spaces directly affects students’ learning, there is no equivalent study supporting similar impact of 3D virtual learning spaces’ colour design on students in 3D VLEs, whether as affordances or constraints to the e-learning process. To fill this gap, this paper examines the various positive and negative emotions expressed by students during exposure to different colours inside 3D virtual educational buildings; in an attempt to determine best practices in digital colour-design of learning spaces inside 3D virtual worlds to enhance students’ overall e-learning experiences and satisfaction within them.

3D Virtual Knowledge Space for Collaboration in New Product Development Processes

The purpose of this article is to create a virtual knowledge space, K-SPACE (Knowledge Space), that enables communication and knowledge sharing between a business level and a plant level for mutual decision-making. Another purpose of a virtual knowledge space is to enable successful collaboration that ensures better quality while reducing costs and time by checking the task progress of departments participating in new product development (NPD) under the concurrent engineering (CE) paradigm. The Croquet software development kit is utilized to develop the knowledge space, which is a small-talk based, object-oriented language. The use of K-SPACE at enterprises that adapt the CE philosophy for NPD processes is expected to reduce both time and cost through fast, accurate, efficient, and collaborative decision making for various conflicting issues.

Symmetry brings an impression of familiarity but does not improve recognition memory

Studies have shown that symmetric stimuli are recognized better than asymmetric stimuli but evidence suggests that this advantage may result from a familiarity bias induced by symmetry. We used a classic episodic memory paradigm to test this bias and see if it truly accounts for the symmetry advantage. Subjects first encoded symmetric and asymmetric figures. During a subsequent recognition phase, they discriminated the encoded (old) figures from new intermixed figures. The recognition rate of old figures was higher with symmetric figures than asymmetric figures. However, the tendency to falsely recognize new figures was also higher when they were symmetric, meaning that the higher recognition rate for symmetric figures was artificially inflated by a response bias. Three other experiments further tested this finding and examined the influence of some variables (rotation in virtual 3D space, stimulus meaningfulness, and redundancy of information) on the bias. A fifth experiment with photo stimuli confirmed that the response bias also applies to objects that we regularly encounter in everyday life. In conclusion, our results show that symmetry does not enhance mnemonic processes but instead induces a response bias leading individuals to judge such stimuli as having been seen.

2D and 3D Traveling Salesman Problem

When a two-dimensional (2D) traveling salesman problem (TSP) is presented on a com- puter screen, human subjects can produce near-optimal tours in linear time. In this study we tested human performance on a real and virtual floor, as well as in a three- dimensional (3D) virtual space. Human performance on the real floor is as good as that on a computer screen. Performance on a virtual floor is very similar, while that in a 3D space is slightly but systematically worse. We modeled these results by a graph pyramid algorithm. The same algorithm can account for the results with 2D and 3D problems, which suggests that deterioration of performance in the 3D space can be attributed to geometrical relations between hierarchical clustering in a 3D space and coarse-to-fine production of a tour.

E_motions in process

This research project maps virtual emotions. Rauch uses 3D-surface capturing devices to scan facial expressions in (stuffed) animals and humans, which she then sculpts with the Phantom Arm/ SensAble FreeForm device in 3D virtual space. The results are rapidform printed objects and 3D animations of morphing faces and gestures. Building on her research into consciousness studies and emotions, she has developed a new artwork to reveal characteristic aspects of human emotions (i.e. laughing, crying, frowning, sneering, etc.), which utilises new technology, in particular digital scanning devices and special effects animation software. The proposal is to use a 3D high-resolution laser scanner to capture animal faces and, using the data of these faces, animate and then combine them with human emotional facial expressions. The morphing of the human and animal facial data are not merely layers of the different scans but by applying an algorithmic programme to the data, crucial landmarks in the animal face are merged in order to match with those of the human. The results are morphings of the physical characteristics of animals with the emotional characteristics of the human face in 3D. The focus of this interdisciplinary research project is a collaborative practice that brings together researchers from UCL in London and researchers at OCAD University’s data and information visualization lab. Rauch uses Darwin’s metatheory of the continuity of species and other theories on evolution and internal physiology (Ekman et al) in order to re-examine previous and new theories with the use of new technologies, including the SensAble FreeForm Device, which, as an interface, allows for haptic feedback from digital data.<strong></strong>