bluuebunny/crossref_metadata_2025 huggingface dataset:
Haptic Virtual Environments for Blind People: Exploratory Experiments with Two Devices
Authors: Jansson G , Petrie H , Colwell C , Kornbrot D. , Fänger J. , König H. , Billberger K. , Hardwick A. , Furner S.
Published: October 2019

This paper is a fusion of two independent studies investigating related problems concerning the use of haptic virtual environments for blind people: a study in Sweden using a PHANToM 1.5 A and one in the U.K. using an Impulse Engine 3000. In general, the use of such devices is a most interesting option to provide blind people with information about representations of the 3D world, but the restriction at each moment to only one point of contact between observer and virtual object might decrease their effectiveness. The studies investigated the perception of virtual textures, the identification of virtual objects and the perception of their size and angles. Both sighted (blindfolded in one study) and blind people served as participants. It was found (1) that the PHANToM can effectively render textures in the form of sandpapers and simple 3D geometric forms and (2) that the Impulse Engine can effectively render textures consisting of grooved surfaces, as well as 3D objects, properties of which were, however, judged with some over- or underestimation. When blind and sighted participants' performance was compared differences were found that deserves further attention. In general, the haptic devices studied have demonstrated the great potential of force feedback devices in rendering relatively simple environments, in spite of the restricted ways they allow for exploring the virtual world. The results highly motivate further studies of their effectiveness, especially in more complex contexts.
Virtual Reality Technology Development in Korea
Authors: Park ChanJong
Published: October 2019

Korea is constructing its information highway scheduled for completion by 2015. However, not all this highway infrastructure is part of the national strategy. The development plan includes extensive software applications for the movie, game, and multimedia industries. At the present time the Internet can represented as the sea of information (cyber space) which can be searched for any information, new concept, or promotion over time and space. The increasing number and demands of Internet users drive the development. In particular, those demands are promoting the movement from 2D to 3D environments, as well as interactions that make the virtual, or cyber, world more closely resemble the real world. With those efforts go an increasing interest in virtual reality (VR), and there is currently much VR research and the development of commercial VR applications taking place in Korea. In this paper I describe the technology trends, the organizations involved in VR research, and introduce the other articles in this issue of the IJVR
Registration of a 3D Model on a Single Image in Wide Angle Augmented Reality
Authors: Lee Youngmin , Wohn Kwangyun
Published: October 2019

This paper presents a new design of a wide angle augmented reality (AR) system and an effective registration method using a single image. The AR system is designed to meet three requirements: (1) the field of view (FOV) of the AR system must be wide enough to view reference constructions in outdoor scenes; (2) the precise registration of virtual objects should be guaranteed at any position of the image; and (3) the registration should be valid after motion of the camera. We use camera calibration and calibration-free methodologies in our approach. The internal parameters of the camera are determined roughly by the camera calibration and how the distortion coefficient of the camera lens is refined. The external parameters are determined by the calibration-free approach. At least four coplanar points forming a projected parallelogram are needed to construct the affine coordinates that are used for the registration. The only presumed condition is that the user specifies some projected parallelogram lines of the reference object interactively. The experimental results demonstrate the display prototype of the wide angle AR system with the distorted images removed and registration of 3D virtual models in static and dynamic camera environments.
A New Simplification Algorithm for Colored or Textured Polygonal Models
Authors: Zhou Kun , Zhang Mingmin , Shi Jiaoying , Pan Zhigeng
Published: October 2019

Many applications in computer graphics require complex and highly detailed models. However, the level of detail actually necessary may vary considerably. It is often desirable to use approximations in place of excessively detailed models to control processing time. A new polygonal mesh simplification algorithm is presented for colored or textured models based on vertex clustering, and a more accurate error-measuring method for vertex clustering is introduced. The algorithm can produce high quality approximations of polygonal models. It makes adaptive subdivision of the bounding box in the original model using octree structure and performs vertex clustering in an error range specified by users. The color or texture information defined over the mesh can be preserved during simplification by constructing a texture map for the simplified mesh. To make a continuous transition between level of detail (LoD) models possible, an efficient interpolating method is also proposed. The efficiency of the algorithm is demonstrated in the experimental results.
Virtual Bronchoscopy
Authors: Heng Pheng-Ann , Fung Ping-Fu , Leung Kwong-Sak , Sun Han-Qiu , Wong Tien-Tsin
Published: October 2019

Patients potentially suffer and are exposed to danger during invasive bronchoscopic diagnosis and surgery. In order to reduce this hazardous risk, we have developed an interactive virtual environment for the simulation of bronchoscopy (in short, called "virtual bronchoscopy"). Because of this state-of-the-art application, medical doctors can now obtain pre-operative information and perform pilot examinations in a virtual environment without any invasive or needless surgery. This 3D lung volume data of the patient is first acquired from CT and/or MRI scanning, without any pain being inflicted upon the patient. Then a vessel-tracking process is used to extract the patient's bronchial tree from the data. It is important to note that while manual tracking is tedious and labor-intensive, fully automatic tracking may not be as reliable in such a critical medical application. Thus a semi-automatic tracking technique called the Intelligent Path Tracker, which provides automation and sufficient user control during the tracking process, is most useful. This methodology is applied to a virtual bronchoscopy session, where doctors can use a 3D pen input device to navigate and visualize the bronchial tree of patients in a natural and interactive manner. To support an interactive frame rate, we also propose a new volume rendering acceleration technique, named IsoRegion Leaping. Through this technique visualization is further accelerated using a distributed rendering process based upon a TCP/IP network of low-cost PCs. Combining these approaches enables a 256x256x256 volumetric data representation of a human lung to be navigated and visualized at a frame rate of over 10 Hz in our virtual bronchoscopy system.
Image-Based Virtual Navigation System for Art Caves
Authors: Lu Dongming , Pan Yunhe
Published: October 2019

Dunhuang Art Cave (DAC), one of the most famous cultural heritage sites in the world, is confronted with serious natural efflorescence. How to virtually rebuild the caves and support their investigation and exploitation with computer graphics (CG) and Virtual Reality (VR) technologies is an urgent and important project. In this paper we discuss in detail the essential technical issues in our image-based virtual DAC navigation system. For DAC modeling of the cave architecture we employ 3D surface modeling, texture and 2D image-based modeling, murals, and painted statues. For DAC rendering we use the level of detail (LOD) method for murals and image-based rendering for painted statues. For DAC shadow generation we investigate a simple 3D model-based solution. Finally, this paper will show the general system architecture as well as demos of virtual navigation.
Multi-Resolution Modeling for Virtual Design
Authors: Cheng Chiyi , Zhang Mingmin , Pan Zhigeng
Published: October 2019

The benefits of multi-resolution modeling techniques in virtual reality are vast, but one essential component of this model is how it can be used to speedup the process of virtual design and virtual prototyping. In this paper we propose a new multi-resolution representation scheme called MRM, which can support efficient extraction of both fixed and variable resolution modeling data for handling multiple objects in the same scene. One important feature of the MRM scheme is that it supports unified selective simplifications and selective refinements over the mesh representation of the object. In addition, multi-resolution models may be used to support real-time geometric transmission of data in collaborative virtual design and prototyping applications. These key features in MRM, may be applied to a variety of VR applications.
Longitudinal Study of Habituation and Participatory Design for Multi-User Shared Virtual Environments
Authors: Ashraf N. , Anderson J. , Douther C. , McKay I. , Jack M. , Platt P.
Published: October 2019

This paper details the results of a longitudinal study of user habituation, usage and involvement with a shared virtual 3D environment acting as a meeting space. The study involved investigation of the effectiveness of a range of design features which were included to enhance communication, discussion and social interaction among a group of four users of the shared space. The users took part in six sessions over a period of seven weeks. The paper focuses on usage of the shared space and details user involvement in the design process in terms of reactions to avatar personalisation; avatar life signs, gestures and navigation control; the means for identifying who is talking; and symbolic acting by avatars. The results indicate the importance of key features for the design of virtual environments. Participants wanted to identify their own protocols for turn-taking in conversation and they wanted simple gesture control. For example, one-click visual buttons for the selection of gestures were preferred to pulldown menus. It took users five or six sessions to complete the participatory design process at which point they were totally comfortable with the use of the virtual meeting space. Finally, symbolic acting was shown to be a viable addition to the shared space to assist group dynamics.
Testing a Biological Weapon Detection System in a Distributed Virtual Reality Environment
Authors: Beckman Paul
Published: October 2019

A study called Bio-Sim was sponsored by the U.S. Army to examine the LR-BSDS (Long-Range Biological Standoff Detection System), a laser-based biological cloud detector. Testing of the device was performed in a distributed virtual reality environment (DVRE). The three primary objectives of the study were to: 1) determine appropriate tactics, techniques, and procedures for use of the LR-BSDS, 2) gain a better understanding of those battlefield situations and characteristics that limit the effective use of the LR-BSDS, and 3) demonstrate the potential to use a DVRE simulation for training using the LR-BSDS. This paper will focus on the third of those objectives. The study consisted of three phases. The first phase involved calculating theoretical concentration limits of a dispersed biohazard as a function of time, dispersion concentration, and distance to sensor. The second phase resulted in a set of abbreviated bio-cloud detection missions run in a DVRE. The third phase was a set of full-length human-in-the-loop trial missions run by trained LR-BSDS operators and helicopter flight crews, using a DVRE and computer-based simulators for the LR-BSDS, helicopter, biocloud dispersion, and bio-cloud transport.
Discursive Citizenship: The Body Politic in Cyberspace
Authors: Kolko Beth
Published: October 2019

Questions of community and identity dominate discussions of cyberspace. Recent work in a variety of disciplines points to a fluidity of identity within virtual environments that is both a determining factor in how the space is used and also a way to begin theorizing the possibilities of the space. Mark Poster, Sherry Turkle, Alluecquere Stone, Lisa Nakamura, and Jennifer Mnookin are a few of the scholars who have provided wide-ranging analyses that resonate with one another in their portrayals of dispersed and fragmented presences in virtual communities. These questions of identity have variously raised issues relating to the body, and much current research on cyberspace addresses the ways in which the material is implicated in the virtual. This paper explores how discursive formations of identity affect community development in virtual environments, primarily with regard to experiments in governance within online communities. In particular, the paper examines how the collaborative nature of cyberspace complicates effective use of virtual environments for complex community functions. While focusing on rhetorical theory, the paper argues that traditional relations between speaker and audience are blurred substantially in cyberspace, sufficiently so that attempts at establishing a kind of communicative ethics online are difficult at best. The premise that cyberspace communities, in particular MUDs (multiuser domains) and MOOs (multiuser object oriented environments), are writing environments wherein discursive negotiation plays a major role in community formation frames the analysis of the rhetorical function of place. Although new media, and increased bandwidth, are expanding the kinds of sign systems that are used to communicate in cyberspace, the claim to identity online is still very much a matter of discursive choice.
Virtual Reality In Paraplegia: A Test Bed Applicationn
Authors: Riva Giuseppe
Published: October 2019

The paper presents an overview of the ergonomic/design issues of a VR-enhanced orthopaedic appliance to be used in rehabilitation of patients with Spinal Cord Injury. First, some design considerations are described and an outline of aims which the tool should pursue are given. Finally, the design issues are described focusing both on the development of a test-bed rehabilitation device and on the description of a preliminary study detailing the use of the device with a long-term SCI patient. The basis for this approach is that physical therapy and motivation are crucial for maintaining flexibility and muscle strength and for reorganizing the nervous system after SCIs.
VRSEMLAB: A Low Cost Virtual Reality System to Illustrate Complex Concepts Involving Spatial Relationships
Authors: Sines P. , Das B.
Published: October 2019

Virtual Reality (VR) is a powerful education/training tool, and its interactive immersive environment is particularly suitable for the illustration of complex concepts involving spatial relationships. Although many virtual reality applications have been developed for education and training, the wide spread use of this technology has been primarily limited by the high cost of VR systems. We have developed VRSEMLAB, a low cost VR application to teach the complex subject of semiconductor device physics to undergraduate students. VRSEMLAB demonstrates an effective method for using virtual reality to model complex 3D systems in an experimental environment free of concerns of physical safety, equipment limitations, and size limitations.
EDITORIAL The International Journal of Virtual Reality 2006 - 05(2)
Authors: Kim Gerard J. , Chen Jim X.
Published: October 2019

Editorial IJVR 5-2
The Virtual Human Platform: Simplifying the Use of Virtual Characters
Authors: Knöpfle Christian , Jung Yvonne
Published: October 2019

In this paper, we will explain our approach to create and animate virtual characters for real-time rendering applications in an easy and intuitive way. Furthermore we show a way how to develop interactive storylines for such real-time environments involving the created characters. We outline useful extensions for character animation based on the VRML97 and X3D standards and describe how to incorporate commercial tools for an optimized workflow. These results were developed within the Virtual Human project. An overview of the project is included in this paper
Virtual Reality Technology and Museum Exhibit
Authors: Hirose Michitaka
Published: October 2019

More than 15 years have passed since the word "virtual reality" became popular in our society. Now VR technology is at the stage where realistic application should be discussed. For example, it is said that museums are now a good application field of VR technology. In this paper, recent VR technologies which can be utilized for museum exhibits are introduced. The topics include sophisticated image environments such as IPT (immersive projection technology), image-based world generation methodology, and "real world VR" supported by wearable computers
Multiresolution Graphics on Ubiquitous Displays using Wavelets
Authors: Wu Fan , Agu Emmanuel , Ward Matthew
Published: October 2019

Large meshes or images cannot be rendered at full resolution on mobile devices such as cell phones, PDAs and laptops since these devices have limited storage, CPU, memory, display, and battery power. Wavelet-based multiresolution analysis can represent meshes and graphics input at multiple Levels of Detail (LODs). We propose UbiWave, a wavelet-based framework for scalable transmission of large meshes and graphics content to heterogeneous ubiquitous computing devices. In UbiWave, a base representation and different levels of wavelet coefficients are pre-generated at the server. An optimal LOD level is transmitted to each mobile client based on its spacification and wireless channel conditions, where the corresponding LOD is reconstructed. To save scarce resources on mobile devices, we render graphics content at the lowest LOD that does not show visual artifacts, called the point of indiscernability (PoI). By rendering content at the PoI instead of the highest resolution, we are able save 61% decode time and 45% energy usage on the client
Projected Reality - Content Delivery Right onto Objects of Daily Life
Authors: Ehnes Jochen , Hirose Michitaka
Published: October 2019

Spatial augmented reality using controllable projector-camera-systems to project onto objects directly, or Projected Reality as we call it, offers the possibility to augment objects without requiring their users to wear or carry any devices. In order to provide the freedom of movement to users, we developed an architecture that allows projected applications to roam a network of projection units to follow the users. The concept of connecting physical objects with content in form of projected applications, although devised for projection based augmented reality systems, can be applied to HMD based or hand held AR systems as well. After a description of our AR projection system and a example application that could be used to provide location specific information to travelers using public transportation systems, we will lay out our vision of a system that may be able to provide content on a global scale
Metazoa Ludens: Mixed Reality Environment for Playing Computer Games with Pets
Authors: Tan Roger K. C. , Cheok Adrian David , Teh James K. S.
Published: October 2019

For better or worse, technological advancement has changed the world to the extent that at a professional level demands from the working executive required more hours either in the office or on business trips, on a social level the population (especially the younger generation) are glued to the computer either playing video games or surfing the internet. Traditional leisure activities, especially interaction with pets have been neglected or forgotten. This paper introduces Metazoa Ludens, a new computer mediated gaming system which allows pets to play new mixed reality computer games with humans via custom built technologies and applications. During the game-play the real pet chases after a physical movable bait in the real world within a predefined area; infra-red camera tracks the pets' movements and translates them into the virtual world of the system, corresponding them to the movement of a virtual pet avatar running after a virtual human avatar. The human player plays the game by controlling the human avatar's movements in the virtual world, this in turn relates to the movements of the physical movable bait in the real world which moves as the human avatar does. This unique way of playing computer game would give rise to a whole new way of mixed reality interaction between the pet owner and her pet thereby bringing technology and its influence on leisure and social activities to the next level
Garden Alive: an Emotionally Intelligent Interactive Garden
Authors: Ha Taejin , Woo Woontack
Published: October 2019

In this paper, we introduce the "Garden Alive" system that allows users to interact with an emotionally intelligent virtual garden by manipulating tangible user interfaces. The Garden Alive aims to provide both entertainment and education. The proposed system is composed of three components. In the first module, tangible user interfaces bridge to the garden in a virtual world. In the second module, an artificial intelligent module consists of two sub-modules: an evolution module and an emotion module. The third module is the virtual garden, which displays growth and the reactions of virtual plants. As for the user interfaces, user's hand gestures are recognized by cameras, the amount of light measured by light detection sensors, and the position of water detected by water detection sensors. Based on this sensed information, the artificial intelligent module determines the evolutionary direction of the plants and changes their emotional state. Our Virtual Garden has adapted the L-system [12] so the virtual plants grow in a similar manner to real plants. In this proposed "Garden Alive" system, there are several kinds of plants and each has different genes that is to individually unique. So we can observe plants evolving for generations by evaluating a proposed fitness function. Finally, we implemented intelligent plants which show emotional reactions according to interaction with the user, instead of simply reacting to stimulus. Therefore, the proposed system is applicable for use to both entertainment and education.
Multi-Modal VR for Medical Simulation
Authors: Indhumathi C , Chen Wenyu , Cai Yiyu
Published: October 2019

Over the past three decades computer graphics and virtual reality (VR) have played a significant role in adding value to medicine for diagnosis and treatment applications. Medical simulation is increasingly used in medical training and surgical planning. This paper investigates the multi-modal VR interface for medical simulation focusing on motion tracking, stereographic visualization, voice navigation, and interactions. Applications in virtual anatomy learning, surgical training and pre-treatment planning will also be discussed.
Volume Decomposition for Hierarchical Skeletonization
Authors: Zhang Xiaopeng , Liu Jianfei , Jaeger Marc , Li Zili
Published: October 2019

Hierarchical skeletons and shape components are important shape features, and they are useful for shape description and shape understanding. Techniques to extract shape components and hierarchical skeletons from volume data are analyzed in this paper based on multiple distance transformations. The application of volume decomposition for the extraction of hierarchical skeletons is emphasized and specified here. This work includes an establishment of the hierarchical structure of the object volume, a decomposition of the volume into simple sub-volumes, an extraction of compact skeleton segments corresponding to each independent sub-volume, and a connection of these skeleton segments into a hierarchical structure reflecting the organization the initial data
DockPro: A VR-Based Tool for Protein-Protein Docking Problem
Authors: Cakici Serdar , Sumengen Selcuk , Sezerman Ugur , Balcisoy Selim
Published: October 2019

Proteins are large molecules that are vital for all living organisms and they are essential components of many industrial products. The process of binding a protein to another is called protein-protein docking. Many automated algorithms have been proposed to find docking configurations that might yield promising protein-protein complexes. However, these automated methods are likely to come up with false positives and have high computational costs. Consequently, Virtual Reality has been used to take advantage of user's experience on the problem; and proposed applications can be further improved. Haptic devices have been used for molecular docking problems; but they are inappropriate for protein-protein docking due to their workspace limitations. Instead of haptic rendering of forces, we provide a novel visual feedback for simulating physicochemical forces of proteins. We propose an interactive 3D application, DockPro, which enables domain experts to come up with dockings of protein-protein couples by using magnetic trackers and gloves in front of a large display.
Real-time Dynamic Simulation of 3D Cloud for Marine Search and Rescue Simulator
Authors: Shen Helong , Yin Yong , Li Yongjin , Wang Pengcheng
Published: October 2019

As the main scenery of sky, the effect of 3D cloud influences the fidelity of visual system and the immersion effect of simulator. In this paper, based on the work of Y. Dobashi and T. Nishita, small region Cellular Automaton is generated and more realistic cloud simulation is improved. The experimental results show that the visual system of simulator can run in real-time and has a relatively higher refresh rate after changeable 3D cloud being applied.
Virtual Reality Simulation of Active Car Suspension System
Authors: Smoker Jason , Baz Amr , Zheng Ling
Published: October 2019

This paper presents the design of a Nonlinear Energy Sink (NES) controller and its application to active sus-pension systems in the Virtual Reality Environment. In this en-vironment, the design engineers are immersed in an audio-visually coupled tele-operated environment whereby direct in-teraction with and control of the design process is achieved in real time. In this manner, the behavior of synthetic models of the full car can be monitored by literally walking around the car and adjusting the design parameters of the suspension as needed to ensure optimal performance while satisfying design and operational requirements. The control actuators which provide forces equivalent to nonlinear stiffness and damping elements are attached to the vehicle in order to actively isolate it from road excitation. The effect of the parameters of the NES controller on the vehicle performance is studied both in the frequency and time domain. The effectiveness of the NES controller is validated by numeri-cal simulation. The robustness of the nonlinear energy pumping process is studied by varying the magnitude of road excitation. The simulation results in the Virtual Reality Environment show that under certain conditions, the nonlinear energy pumping can be induced and significant vibration isolation can be achieved. The performance of vehicle including the ride com-fort and road holding capability can be improved significantly. When the magnitude of road excitation is increased, the capaci-ty of the NES to absorb energy from the main system is also enhanced. This is very important to achieve vibration isolation objectives. The virtual reality simulation results also show that the nonlinear NES controller performs better than the classical LQR controller particularly as the road condition becomes worst.
Mixed Reality Entertainment and Art
Authors: Cheok Adrian David , Haller Michael , Fernando Owen Noel Newton , Wijesena Janaka Prasad
Published: October 2019

Social and physical interactions are new paradigms that outline the vision of the next generation of entertainment. We can provide these interactions through employment of technologies such as mixed reality to merge the human physical world with the virtual game world. However, there are a few obstacles in achieving physical, mobile, tangible and social interaction for people's entertainment. The authors had organized a workshop on this topic of "Mixed Reality Entertainment and Art" at the ISMAR 2007 conference in Nara, and the presentations are summarized in this paper. Furthermore, the authors detail their related systems, including BlogWall, MediaMe, and Shared Design Space to provide artistic and entertainment mixed reality.
Enhancing Collaborative Manipulation Through the Use of Feedback and Awareness in CVEs
Authors: Garcia Arturo S. , Molina José P. , Martínez Diego , González Pascual
Published: October 2019

In the research community, Collaborative Virtual Environments (CVEs) developers usually refer to the terms awareness and feedback as something necessary to maintain a fluent collaboration when highly interactive task have to be performed. However, it is remarkable that few studies address the effect that including special kind of awareness has on the task performance and the user experience.This paper proposes how to face the implementation of awareness in order to be taken into account early in the development of a CVE. In addition, it is also described an experiment that was carried out to evaluate the effect of providing some visual cues, showing that users tend to make more mistakes when they are not provided.
Reconstruction Techniques for Image Analysis of Ancient Islamic Mosaics
Authors: Gil Francisco Albert , Gomis José María , Pérez Manuel
Published: October 2019

This paper presents a methodology for tile image reconstruction. This methodology is integrated in a computer tool that allows automatic image analysis. Both, the reconstruction and analysis techniques are based on vectorial tools, the application of the theory of symmetry groups and perceptual psychology. Image analysis allows us to obtain information about design patterns which is used to restitute (recover missing motifs), unify (choose between different motifs that should be equal) and standardize (fit motifs exactly to their symmetry axes and rotation centers) old designs. This methodology for tile image reconstruction has been applied to different Islamic mosaics from the Alhambra of Granada (Spain), the Aq-Saray Palace of Shar-i-Sabz (Uzbekistan) and the Red Fortress of Agra (India). The analysis results are presented in this paper.
A Groupware for Pigment Identification in Cultural Heritage
Authors: Palazzi Claudio E. , Roccetti Marco
Published: October 2019

The preservation of cultural heritage is a multidisciplinary field of study that is aimed at analyzing and preserving ancient artifacts. Nowadays, cultural heritage investigators can make use of available non-invasive solutions able to provide useful information about materials, techniques, and retouches. Yet, investigations on artworks are manually performed with very little automation. This is due to the need for the unique expertise of human operators but also to the lack of adequate digital support. To this aim, we have designed a groupware for supporting collaborative work among cultural heritage investigators even when located far from each other. As a practical case study we have chosen the pigment identification problem in artworks and included in the groupware an automated procedure for selecting investigation areas and for matching unknown pigments on the considered artwork with known standards in a database.
Virtual Reality and Physical Activity: Attentional and Behavioral Aspects
Authors: Dagonneau Virginie , Maïano Christophe , Mercier Charles-Symphorien , Mestre Daniel R.
Published: October 2019

The present study tested the effects of sensorial inputs on performance and attentional focus during physical training on a computerized ergometer. 18 students were involved in this study. The experimental procedure consisted in a 3x3x4 mixed design, with 3 practice modalities (virtual feedback, virtual feedback and music, virtual and heart rate feedback) 3 course phases (e.g., flat, uphill, downhill) and 4 sessions. The virtual feedback was a video film of the course subjects had to complete. Video display speed was proportional to the subject's pedalling speed. Results show a training effect on the subjects' overall performance and a reduction of the time spent gazing at video feedback across sessions. The results are discussed in terms of the functional status of sensorial stimulation and its interactions with exercise intensity and subject performance.
Virtual Environments for Sport Analysis: Perception-Action Coupling in Handball Goalkeeping
Authors: Vignais Nicolas , Bideau Benoit , Craig Cathy , Brault Sébastien , Multon Franck , Kulpa Richard
Published: October 2019

In sports science, the link between the experimental protocol and the subject's behaviour in real condition is a key issue. Virtual reality enables to examine this topic because of the reproducibility of situations and the total control of animated humanoids in situations similar to the real world. This study aimed to analyze the influence of the degree of perception-action coupling on the performance of handball goalkeepers in a virtual environment. 8 national handball goalkeepers were asked to react to the actions of a virtual handball thrower in two conditions: a perception-action uncoupled condition (defined as a judgment task) and a perception-action coupled condition (defined as a motor task). In the judgment condition, goalkeepers were asked to make a perceptual judgment with their hand in their own time after the virtual throw; in the motor task condition, goalkeepers had to react in real-time to the virtual throwing motion. Results showed that percentage of successful response was higher in the motor task condition and radial error (distance between the ball and the closest limb when trial was unsuccessful) was lower for the same condition. Implications of our findings are discussed, as well as suggestions for further research..
Automatic Surface Scanning of 3D Artifacts
Authors: Fang Shiaofen , George Basil , Palakal Mathew
Published: October 2019

This paper describes an automatic 3D surface scanning technique using a 3D scanner. It allows the acquisition of a complete surface model of a 3D artifact without any manual registration and human interference. A two-pass approach is applied using a rotary table. In the first pass, a sequence of 2D images of the artifact are collected using a small rotation step. An image similarity measure is then taken to compare adjacent images to assess the differences between consecutive images to establish the optimal scanning angles. In the second pass, 3D scans are taken using the scanning angles derived in the first pass. An Iterative Closest Point (ICP) algorithm is employed to provide precise data alignment of neighboring scans. A new space encoding algorithm is developed to filter the over sampling areas for smoother polygonization. This technique is being implemented in a digital library project for the reconstructions of 3D computer models for artifacts from a collection in several Museums.
Space Time Carving for Shape and Motion Recovery
Authors: Sakaue Fumihiko , Takami Masaaki , Sato Jun
Published: October 2019

Recently, a lot of methods for shape and motion reconstruction have been studied extensively. This paper describes a method for simultaneous shape and motion reconstruction without any corresponding points. We call the method space-time carving. The proposed method is based on a space carving method which can reconstruct 3D shape without any corresponding points. The method uses photo-consistency for 3D space carving. Our proposed method also uses photo-consistency for carving high dimensional space which represents not only shape but also motion. As a result, the proposed method can recover not only 3D shapes but also 3D motions of objects. The experimental results show that the proposed method works well.
Image-Based Modeling from a High -Resolution Route Panorama
Authors: Shibata Ryuji , Nagahara Hajime
Published: October 2019

Image-based modeling methods for generating 3D models from an image sequence have been widely studied. Most of these methods, however, require huge redundant spatio-temporal images to estimate scene depth. This is not an effective use of capturing higher resolution texture. On the other hand, a route panorama, which is a continuous panoramic image along a path, is an efficient way of consolidating information from multiple viewpoints into a single image. A route panorama captured by a line camera also has the advantage of capturing higher resolution easily. In this paper, we propose a method for estimating the depth of an image from a route panorama using color drifts. The proposed method detects color drift by deformable window matching of the color channels. It also uses a hierarchical belief propagation to estimate the depth stably and decrease the computation cost thereof.
Exploring Wireless Mesh Networks for Collaborative Augmented Reality Environments
Authors: Hamidian Ali , Palazzi Claudio E. , Chong Tin Y. , Gerla Mario , K�rner Ulf
Published: October 2019

Exploring Wireless Mesh Networks for Collaborative Augmented Reality Environments
Communications and Decisions of Autonomous Vehicles in Virtual Environments
Authors: R. Ronald R. , Yin Zhishuai , Lin Yingzi , Kamarthi Sagar
Published: October 2019

In many virtual environments, autonomous objects, such as people and vehicles, are essential to increase the feeling of presence. A goal is to have autonomous objects behave as humans, or in the case of vehicles, as if humans controlled them. Such objects are known as intelligent autonomous objects. We present a combination of a communication model and a decisionmaking model to achieve the goal of modeling autonomous objects that behave intelligently. Both models are attached to autonomous objects that represent people and vehicles in a virtual environment. This enables such an autonomous object to be an independent entity that is self-motivated and self-controlled. These intelligent autonomous objects are able to communicate with other autonomous objects via their communication model according to decisions reached by their decision-making model. The decision-making model relies on the communication model to investigate possible outcomes before making decisions. The communication model defines senders, receivers, contents, and channels (media through which content is transferred) in realtime to gather desired information from specified objects. The decision-making model is divided into two levels, the global level and the local level. These work, respectively, with global information perceived by a perception model and the local information received by the communications model. A group of logic rules are formulated as decision trees to model the process of making decisions on the basis of real-time activities. We used traffic and people, in a virtual environments based driving simulator, as examples of intelligent communicating autonomous objects
PEGASE: A Generic and Adaptable Intelligent System for Virtual Reality Learning Environments
Authors: Buche Cédric , Bossard Cyril , Querrec Ronan , Chevaillier Pierre
Published: October 2019

The context of this research is the creation of human learning environments using virtual reality. We propose the integration of a generic and adaptable intelligent tutoring system (Pegase) into a virtual environment. The aim of this environment is to instruct the learner, and to assist the instructor. The proposed system is created using a multi-agent system. This system emits a set of knowledge (actions carried out by the learner, knowledge about the �eld, etc.) which Pegase uses to make informed decisions. Our study focuses on the representation of knowledge about the environment, and on the adaptable pedagogical agent providing instructive assistance
Collaborative Virtual Surgery: Techniques, Applications and Challenges
Authors: Qin Jing , Choi Kup-Sze , Pang Wai-Man , Yi Zhang , Heng Pheng-Ann
Published: October 2019

While considerable effort has been dedicated to improve medical education with virtual reality based surgical simulators, relatively little attention is given to the simulation of the collaborative procedures in distributed environments. In this paper, we first present a literature review of techniques involved in the development of collaborative simulators, including network architecture, transmission protocol, collaboration mechanism, schedule algorithm, collaborative user-interaction feature and haptic communication. We introduce the details of each technique and discuss the advantages and drawbacks. Then, we review some of the existing applications to illustrate how to apply these techniques to implement an efficient and robust collaborative simulator. Finally, we discuss the challenges that need to be addressed in the future.
Recent Advances on Human Crowd Simulation
Authors: Mao Tianlu , Jiang Hao , Xia Shihong , Wang Zhaoqi
Published: October 2019

Human crowd simulation is a new technology in the virtual reality field. Since it could simulate evacuation, it has strong demands in risk assessment for public buildings. In this paper we discuss the development of the main related research topics, including semantic description for virtual environments and crowd models which generate continuum human flow. Additionally, we introduce a system named Guarder that is designed for human crowd simulation and is suit for simulating evacuation in public buildings. We also demonstrate some simulation results of Guarder to show that it could efficiently simulate evacuation in a large-scale and complex environment.
Agile Development of WebVR Applications
Authors: Shen Zhixing , Jia Jinyuan
Published: October 2019

This paper presents a novel "Roll and Raid" WebVR development model to solve the problems of conventional WebVR development practices. Firstly, agile methodology is introduced into the life cycle of developing WebVR. Secondly, some principles are further proposed to guide the entire WebVR development process. We choose some typical WebVR projects to verify its effectiveness. The experimental results show that our proposed "Roll and Raid" model is much advantageous over conventional WebVR development methods with lower cost, higher efficiency, stronger adaptiveness and easier team management.
Semantic Modeling Approach of 3D City Models and Applications in Visual Exploration
Authors: Xu Weiping , Zhu Qing , Zhang Yeting
Published: October 2019

In recent years, the necessity of the incorporation of semantic information into three-dimensional city models (3DCMs) has become a consensus in 3D GIS field. In order to provide practical support for visual applications concerned with semantics, this paper firstly presents an extended semantic model based on the CityGML standard, which was worked out for the general storage and representation of semantics. In this model, concepts like Room, Corridor and Stair are all derived from concept Space which corresponds to the concept of Room in CityGML. This extension will benefit the indoor structure representation. Geological feature is also supported by the model for the underground analysis. Next, for the promotion of semantic modeling by this model, a semi-automatic process of semantic enrichment is implemented in a data integration tool. It provides an adaptive way to link semantics with pure geometry. Finally, two typical cases of visual exploration are illustrated to prove the model's practicability in a national 3D GIS project of China. One is indoor routing, which adopts this model to extract the geometric path and thus enrich traditional semantic-enhanced navigation routine; another case is unified profiler, where semantics are intergrated in order to fill up the cross section correctly and ensure the topological and semantic consistency.
A Hierarchical Model of Motor Skill for Haptic-assisted Virtual Reality Training
Authors: Wang Dangxiao , Zhang Yuru , Wu Jun
Published: October 2019

Model of motor skill pattern is a fundamental component to support feedback mechanism in haptic-assisted motor skill training. Because of the diversity of manipulation tasks in real world, it is a challenge to construct a generic model for various motor skill patterns. Considering fine motor skill mediated by a rigid tool, criteria for a general model of motor skill are identified: generality, quantifiable representation and the capability to support real-time error computation. A hierarchical motor skill model is proposed in a two-level architecture: the spatial-temporal coupling mechanism in task level and the quantified representation in action level. The purpose of task level is to decompose a motor skill into basic elements that can be described with quantified representation. The purpose of the action level is to give quantified representation in each single dimension in the Cartesian Space. Based on the combinations of independent variants, mapping functions in the action level are classified as five basic types. The proposed model can provide a systematical view to compare various motor skills in literatures, and thus can help us to identify unexplored topics in haptic-enabled motor skill training area. Furthermore, examples of two motor skill tasks show that the proposed model can provide a systematic way to design training system for complex motor skills.
Automating Terrain Texturing in Real-Time Using a Rule-Based Approach
Authors: Ferraris John , Gatzidis Christos , Tian Feng
Published: October 2019

This publication proposes a novel approach to automatically colour and texture a given terrain mesh in real time. Through the use of weighting rules, a simple syntax allows for the generation of texture and colour values based on the elevation and angle of a given vertex. It is through this combination of elevation and angle that complex features such as ridges, hills and mountains can be described, with the mesh coloured and textured accordingly. The implementation of the approach is done entirely on the GPU using 2D lookup textures, delivering a great performance increase over typical approaches that pass colour and weighting information in the fragment shader. In fact, the rule set is abstracted enough to be used in conjunction with any colouring/texturing approach that uses weighting values to dictate which surfaces are depicted on the mesh
Natural Feature Detection on Mobile Phones with 3D FAST
Authors: Weimert Achim , Tan Xueting , Yang Xubo
Published: October 2019

In this paper, we present a novel feature detection approach designed for mobile devices, showing optimized solutions for both detection and description. It is based on FAST (Features from Accelerated Segment Test) and named 3D FAST. Being robust, scale-invariant and easy to compute, it is a candidate for augmented reality (AR) applications running on low performance platforms. Using simple calculations and machine learning, FAST is a feature detection algorithm known to be efficient but not very robust in addition to its lack of scale information. Our approach relies on gradient images calculated for different scale levels on which a modified9 FAST algorithm operates to obtain the values of the corner response function. We combine the detection with an adapted version of SURF (Speed Up Robust Features) descriptors, providing a system with all means to implement feature matching and object detection. Experimental evaluation on a Symbian OS device using a standard image set and comparison with SURF using Hessian matrix-based detector is included in this paper, showing improvements in speed (compared to SURF) and robustness (compared to FAST)