• The Journal of the Korea institute of electronic communication sciences
• /
• v.2 no.3
• /
• pp.157-162
• /
• 2007

The goal of researching a proper crowd animation is to design system that is satisfied with the reality of scenes, performance of system, and interaction with users to show the crowd vividly and effectively in virtual underwater world. In this paper, we smartly expressed the behavior patterns for flocks of fish in virtual underwater and we made up for the weak points in spending time and cost to produce crowd animation. We compared with the number of mesh, the number of fish, the number of frame, elapsed time, and resolution and analyzes them with the fish behavior simulating system. We developed a virtual underwater simulator using this system.

• Journal of Institute of Convergence Technology
• /
• v.5 no.2
• /
• pp.37-42
• /
• 2015

This paper presents the effects of the computational time-varying delay on the stability of the haptic system that includes a virtual wall and a first-order-hold method. The model of a haptic system includes a haptic device model with a mass and a damper, a virtual wall model, a first-order-hold model and a computational time-varying delay model. In this paper, the maximum of the computational time-varying delay is assumed to be as much as the sampling time. Using the simulation, it is analyzed how the sample-hold methods and the computational time-varying delay affect the maximum available stiffness. As the maximum of computational time-varying delay increases, the maximal available stiffness of a virtual wall model is reduced.

• The Transactions of the Korea Information Processing Society
• /
• v.6 no.11S
• /
• pp.3243-3250
• /
• 1999

There are many problems to be satisfied the various commercial demand in the present VRML node, and the VRML-based system by the contact with other technology is burdened with the direct participation of developer related with it. In this study, remote control and monitoring system using EAI(External Authoring Interface) is reposed to overcome the limit of VRML. In other words, This study is about mechanism of interaction between control and monitoring subject in real world and object in virtual world mapped with it. Object oriented method by one to one mapping of the Java class which have VRML virtual world and the object control is proposed. Introduction method of video monitoring through method of image synthesis and the integrated development environment is described. Finally automobile-gate control system based on the development method of Internet virtual reality-based system which is proposed in this study is described.

• Proceedings of the KSRS Conference
• /
• 2004.10a
• /
• pp.77-80
• /
• 2004

In this study the spatial distribution characters of burnt forest site was first considered by analyzing spatial data and monitoring forest landscape before/after lire to restore the site. Then suitable tree species on each forest site should be selected through the weighted score analysis of GIS analysis methods. Finally. the best forest stand arrangement method could be simulated on the system for the advanced reforestation technology in Korea. For this purpose, the virtual reforestation system was implemented by using the concept of virtual GIS and CBD (Component Based Development) method. By use of this system the change of forest landscape of burnt forest area some years after reforestation practice could be detected and monitored by applying the site index and 3D modeling method.

• 제어로봇시스템학회:학술대회논문집
• /
• 2001.10a
• /
• pp.153.1-153
• /
• 2001

This paper describes a development of rehabilitation training system for the postural balance control. A new rehabilitation training system, designated as a virtual cycling system, was developed to improve postural balance control by combining virtual reality technology with an unfixed bicycle. In this experiment, 20 normal adults were tested to investigate the influencing parameters of postural balance control. In order to evaluate the usefulness and the training effects of the system, several parameters Including path deviation, cycling velocity, cycling time, center of pressure, and head movement were evaluated and analyzed quantitatively. Also, to improve the effect of balance training, the visual feedback information related to the subject´s weight shift was ...

• Proceedings of the Safety Management and Science Conference
• /
• 2002.11a
• /
• pp.171-177
• /
• 2002

In the real environment, it is very limited for the trainees to participate the effective training using actual training equipments by themselves and also to simulate several hazard situations for safety because of the direct exposure to the hazards of the actual system. But the virtual environment(VE) can help the trainees to get the effective training participating by themselves and to simulate all kind of possible situation without the exposure to the hazards of the actual system. In this paper, the new idea is proposed for developing the virtual driving system to provide a realistic driving experience for safety driving. The proposed idea contains the contents of a virtual driving system.

• Journal of the Korea Safety Management & Science
• /
• v.4 no.4
• /
• pp.45-52
• /
• 2002

In the real environment, it is very limited for the trainees to participate the effective training using actual training equipments by themselves and also to simulate several hazard situations for safety because of the direct exposure to the hazards of the actual system. But the virtual environment(VE) can help the trainees to get the effective training participating by themselves and to simulate all kind of possible situation without the exposure to the hazards of the actual system. In this paper, the new idea is proposed for developing the virtual driving system to provide a realistic driving experience for safety driving. The proposed idea contains the contents of a virtual driving system.

• Current Optics and Photonics
• /
• v.5 no.6
• /
• pp.660-671
• /
• 2021

We present a novel optical system for an augmented reality head-up display (AR HUD) with two virtual images at different conjugates by employing a confocal off-axis two-mirror and introducing the horopter circle. For a far virtual image with large asymmetrical aberrations, we initially obtain an off-axis two-mirror system corrected for these aberrations and compensated for the down angle by configuring its parameters to satisfy the confocal and Scheimpflug conditions, respectively. In addition, this system is designed to reduce the biocular parallax by matching Petzval surface into the longitudinal horopter circle in a near virtual image. This design approach enables us to easily balance the residual aberrations and biocular parallax when configuring the optical system with two different conjugates, which results in an AR HUD available for near and far virtual images together.

• Journal of the Korean Society for Precision Engineering
• /
• v.24 no.10
• /
• pp.137-145
• /
• 2007

The purpose of this study is developing a virtual bicycle system for improving the ability of postural balance control for adults in various age groups. The system consists of an exercise bicycle that allows tilt in accordance with the postural balance of the subject in the system, a visual display that shows virtual road, and a visual feedback system. The rider of the system tries to maintain balance on the bicycle with a visual feedback of a virtual road while the pedaling speed, the heading direction, and various weight distribution information are updated to the subject as visual feedbacks in the display. A series of experiments were performed with various subjects to find the factors related to postural balance control in the system. The related parameters obtained were weight shift, magnitude of the deviation from the center of the virtual road, and variables related to the movement of the center of pressure. The results found that the ability to control postural balance in the system improved with the presentation of visual feedback information of the distribution of weight. It was also found that the general performance of the subject on balance in the system improved after ten days long training. The results show that the newly developed system can be used for the diagnosis of postural balance as well as for the stimulation of various senses such as vision and somatic sense in the field of rehabilitation training.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2007.04a
• /
• pp.421-425
• /
• 2007

The application of 3 dimensional virtual reality continuously pursues 3 dimensional system implementation in geographical information system, and is applied and studied in various fields like visualization, simulation, and 3 dimensional analysis. Orthoimage produced to construct basic data of virtual city is evaluated in accuracy, to fall in allowable error of the specification of image map generation. In this paper, 3 dimensional virtual city is constructed and evaluated around Bucheon University using 3 dimensional virtual reality technique and digital photogrammetry. Consequently, the constructed 3 dimensional virtual city around Bucheon University can visualize 3 dimensional reality, to help making decision. It can be substituted for existed 2 dimensional GIS in public and private sectors, and be helpful to decision makers.