Kyoung Shin Park

Effects of network characteristics on human performance in a collaborative virtual environment

We assessed the effects of network latency and jitter on a cooperative teleoperation task in a collaborative virtual environment. Two remote partners worked together to manipulate shared virtual objects over a network. The task was to minimize the time to transfer a ring through one of four paths with the least number of collisions. The performance of human subjects was measured and analyzed quantitatively as a function of network latency: 10 and 200 msec delays with and without jitter. Jitter had the greatest impact on coordination performance when the latency was high and the task was difficult. These results are discussed in light of current and future CVE tasks.

A review of tele-immersive applications in the CAVE research network

This paper presents an overview of the tele-immersion applications that have been built by collaborators around the world using the CAVERNsoft toolkit, and the lessons learned from building these applications. In particular the lessons learned are presented as a set of rules-of-thumb for developing tele-immersive applications in general.

CAVERNsoft G2: a toolkit for high performance tele-immersive collaboration

This paper describes the design and implementation of CAVERNsoft G2, a toolkit for building collaborative virtual reality applications. G2s special emphasis is on providing the tools to support high-performance computing and data intensive systems that are coupled to collaborative, immersive environments.This paper describes G2s broad range of services, and demonstrates how they are currently being used in a collaborative volume visualization application.

Adaptive networking for tele-immersion

Tele-Immersive applications possess an unusually broad range of networking requirements. As high-speed and Quality of Service-enabled networks emerge, it will becoming more difficult for developers of Tele-Immersion applications, and networked applications in general, to take advantage of these enhanced services. This paper proposes an adaptive networking framework to ultimately allow applications to optimize their network utilization in pace with advances in networking services. In working toward this goal, this paper will present a number of networking techniques for improving performance in tele-immersive applications and examines whether the Differentiated Services mechanism for network Quality of Service is suitable for Tele-Immersion.

Enhanced Image Mapping Algorithm for Computer-Generated Integral Imaging System

An enhanced image mapping algorithm is proposed for a real-time computer-generated (CG) integral imaging system. The proposed algorithm, viewpoint vector rendering, can be easily adapted to generate a set of elemental images from complex three-dimensional (3D) objects and is less affected by system factors and object image quality than previous methods. In addition, it can support all the display modes of the integral imaging system. The feasibility and efficiency of the proposed approach are verified and analyzed through rendering experiments. Using this technique, it is possible to realize an interactive CG integral imaging system which can be applied to virtual reality.

Viewpoint Vector Rendering for Efficient Elemental Image Generation

This paper presents a fast elemental image generation algorithm, called the Viewpoint Vector Rendering (VVR), for the computer-generated integral imaging system. VVR produces a set of elemental images in real-time by assembling the segmented area of the directional scenes taken from a range of viewpoints. This algorithm is less affected by system factors such as the number of elemental lens and the number of polygons. It also supports all display modes of the integral imaging system, real, virtual and focused mode. This paper first describes the characteristics of integral imaging system. It then discusses the design, implementation, and performance evaluation of the VVR algorithm, which can be easily adapted to render the integral images of complex 3D objects.

Effects of guided and unguided style learning on user attention in a virtual environment

In this paper, we investigated the effects of guided and unguided style VR learning on user attention and retained knowledge. We conducted a study where users performed guided or unguided style learning in the virtual environment while user attention was measured through an eye tracking system and physiological sensors. The virtual environment contained the five specific events associated with different stimuli, but the guided task was designed to provide the specific goals whereas the unguided task asked the user to actively search for the interesting items. The results showed that the unguided task followed by the guided task made a considerable learning effect by giving a preview to the user. In addition, tactile feedback, sudden view point change, unique appearance and behavior, and sound stimuli played an important factor in increasing human attention states that also induced enhancing human memory about VR experience.

Emotional intelligent contents: expressing user's own emotion within contents

This paper presents an Emotionally Intelligent Contents (EIC) framework. This framework helps to create content that changes its elements (such as textures, color, light and sound) dynamically in response to a users emotional state. Also, this emotionally intelligent content allows users to add their own emotion characters at run-time. This paper presents an overview of the EIC framework designed to adapt a game environment to a users emotional state as measured physiologically or through an explicit rating of ones affective state. It will then describe a couple of applications built with this framework.

The 3d sensor table for bare hand tracking and posture recognition

The 3D Sensor Table system senses the movement of bare-hand and recognizes simple hand postures, such as stretched-hand, fist, and knife-shape hand. This system is designed for user interaction with real-time two- and three-dimensional graphics applications. It uses the electric field sensing technique to track bare-hand movements up to 30cm away from the display surface. This paper describes an overview of the system design, implementation, and algorithm for the 3D hand position and posture recognition.

Design and Development of a Distributed Tabletop System Using EBITA Framework

Over the past decade, tabletop systems are becoming more popular. However, prior works on tabletop system have mostly focused on supporting user interactions with digital contents on one single tabletop display, which are not easily extendable. In this paper we present a new scalable distributed tabletop system consisted of master/slave computer and tangible interfaces to provide high-resolution interactive tabletop display surfaces. Our work is to develop a tabletop system constructed with LCD panels and a cluster of low-cost commodity PCs to support a large highresolution scalable tiled display. It also employs the tangible user interface using the infrared camera tracking and tangible blocks to support intuitive user interaction on the tabletop surface. In this research, EBITA (Environment for Building Interactive Tangible Applications) framework is developed to support various modules necessary for easy construction of any interactive high-resolution applications that run on the distributed tabletop system. This paper briefly describes the design of EBITA framework and detail implementations of the current prototype of distributed tabletop system. Then it demonstrates two applications developed using EBITA framework: 2D high-resolution image viewer and 3D block crash game.