• Journal of the Korea Computer Graphics Society
• /
• v.22 no.3
• /
• pp.31-41
• /
• 2016

This study proposes suitable input processing technique for producing the mobile platform based virtual reality contents. First of all, we produce the mobile platform based virtual reality interactive contents to be used in experiments for improve user's immersion who experience the virtual reality contents, get interests and design the input processing that easily controllable. Then design the input processing technique in two methods, with gamepad that accessibility to mobile and with directly through user's gaze to interface. Through virtual reality based input processing technique that we proposed, we analyse effect of improve user's immersion, cause of get interests and whether provide the convenience or not for controlling contents through experiments. Moreover we verify whether bring negative psychological elements like sickness, fatigue or not.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.22 no.4
• /
• pp.790-800
• /
• 1998

This paper presents a haptic rendering algorithm in the case that the virtual environment elastically deforms in response to the force applied by a user with a virtual tool. Considering friction, elasticity, multiple contacts and dynamics of the virtual object, this algorithm lets the operator have the feel of interactions in the virtual environment as close as to the reality. Based on the proposed algorithm several experiments are conducted and its effectiveness is confirmed.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.18 no.3
• /
• pp.255-260
• /
• 2009

This paper presents an experimental result of virtual mode input shaping for positioning stage. Input shaping is liable to increase the rise time of the system, which often degrades the performance of system. The virtual mode input, shaping is an input shaper design method to improve this problem. Experiments are performed with a precise positioning stage with a flexible beam of which natural frequency is adjustable. The experimental results show that the virtual-mode shaper is useful to reduce the rise time as well as the residual vibration of precise positioning stages.

• 제어로봇시스템학회:학술대회논문집
• /
• 1996.10b
• /
• pp.125-129
• /
• 1996

This paper presents the haptic rendering algorithm which gives the feel information to the operator by manipulating a virtual tool with a haptic device in the simulated environment. The movement of a virtual tool grasped by the operator, which is modeled as a square is displayed in the graphic screen of a computer and the virtual environment is modeled as deformable thin film. When the tool contacts with the virtual environment, the operator is forced to feel the contact and the feature of the deformed virtual environment through the torque control of th haptic device. Contact situations are modeled as close as to the reality considering friction, elasticity and multiple contacts. Several experiments are conducted and the effectiveness of the proposed algorithm is confirmed.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2000.06a
• /
• pp.93-105
• /
• 2000

This paper describes prototype Virtual Reality Ship Simulator (VRSS) that we have recently developed next-generation training equipment based on the virtual reality (VR) technology. The inherent defects of conventional ship simulators are enormous costs and difficult system upgrade due to the system construction, such as large mock-up bridge system, wide visual presentations, In this paper, to cope with those problems, we explored VR technology that can give realistic environments in a virtual world. Then we constructed prototype VRSS system, which is, consists of PC-based human sensors, and Databases set having 3D object models and coefficients of Head Related Transfer Functions (HRTFs). 3D-WEBMASTER authoring tool was used as Virtual Reality Modeling Language (VRML). Using the VRSS system, we constructed Port an Passage Simulator for the harbor of INCHON in Korea, and Ship and Sea State Simulator for an arbitrary given sea environmental states by user. Through many simulation tests, we testified the efficiency of developed prototype VRSS by subject assessment with five participants. Then, we present results on the simulation experiments and conclude with discussion of evaluation results.

• Korean Journal of Computational Design and Engineering
• /
• v.14 no.4
• /
• pp.271-280
• /
• 2009

An experience based training system concerning various fire situations which may result many casualties has been required to make rapid decision and improve the responsiveness. Recently, the necessity of virtual reality (VR) based training system which can replace a dangerous full-scale fire training and be easily adopted to the training or evaluation process is increasing. This study constructed tile virtual environment according to pre-defined scenarios, utilized the FDS(Fire Dynamics Simulator), three dimensional computational fire analysis program, to derive numerically simulated data on the propagation of fire. Finally, by visualizing the realistic fire and smoke behavior through virtual reality technique and implementing real-time interaction, we developed a VR-based fire training simulator. Also, in order to ensure the sense for tile real of a virtual world and reaI-time performance at the same time, we proposed appropriate data processing and space search algorithms, demonstrate d the value of proposed method through experiments.

• Journal of Korea Multimedia Society
• /
• v.24 no.11
• /
• pp.1560-1566
• /
• 2021

Cyber Sickness, which occurs when using Virtual Reality contents, is the most serious problem in immersive Virtual Reality contents. The purpose of this study is to identify the effects and causes of graphic environmental factors on Cyber Sickness in Virtual Reality contents. To this end, cyber sickness experiments were conducted according to the light source and material settings, which are most commonly used in graphical environmental elements. Cyber Sickness measurements were based on the Simulator Sickness Question(SSQ) tool to derive an index that causes Cyber Sickness As a result of the analysis, the smaller the surface roughness, the higher the degree of Cyber Sickness, and the smaller the surface roughness, the smoother the surface of the 3D object, and many specular reflections from the light source occurred, which was confirmed to be the cause of great Cyber Sickness.

• The Journal of Korean Association of Computer Education
• /
• v.11 no.1
• /
• pp.23-32
• /
• 2008

In this paper, we have investigated the education effect of a web-based virtual laboratory for digital logic circuits which consists of multimedia contents about the usages of equipments for logic circuit experiments and the experimental logic circuits. In case of the engineering experiment of the lower grades in universities, preunderstanding about the usages of experimental equipments and the experimental circuits is necessary for the learners to conduct the experiments well. But it is impossible for the learners to have access to the real experimental equipments earlier due to the lack of equipments and the difficulty in management of the equipments. We have implemented the digital logic circuit virtual laboratory which provides the same experimental environment as a real experimental lab, and the learner can conduct the same experiments as the real ones before the real laboratory class. The learners using the laboratory have reduced the experiment completion time by the average of about 8.2% during a term, compared with the learners not using the lab.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.9 no.5
• /
• pp.1184-1192
• /
• 2008

There have been a large number of trials of the experimental education in engineering using virtual laboratories implemented in virtual space, namely on the Web. Although virtual education is regarded as an effective educational means that overcomes the limit of time and space and bring high teaming effects, the problem of lack of reality must be solved. The present study proposed and implemented a real-time remote laboratory as a solution for the problem of lack of reality in virtual education. The remote laboratory provides functions with which learners can perform experiments by remote-controlling circuits and equipment related to experiments and practices on the Web and gets data and image information, so through it learners can make realistic experiments at any time and in any place. The remote laboratory module based on Internet open sources such as JAVA Web start technology, FTP technology and Telnet technology in server-client environment can be implemented at low cost, and is effectively applicable to engineering experiment education in various areas related to real-time hardware control.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.14 no.4
• /
• pp.1520-1542
• /
• 2020

Traditional software testing typically uses many physical resources to manually build various test environments, resulting in high resource costs and long test time due to limited resources, especially for small enterprises. Cloud computing can provide sufficient low-cost virtual resources to alleviate these problems through the virtualization of physical resources. However, the provision of various test environments and services for implementing software testing rapidly and conveniently based on cloud computing is challenging. This paper proposes a multilayer cloud testing model based on cloud computing and implements a hybrid cloud testing system based on virtual machines (VMs) and networks. This system realizes the automatic and rapid creation of test environments and the remote use of test tools and test services. We conduct experiments on this system and evaluate its applicability in terms of the VM provision time, VM performance and virtual network performance. The experimental results demonstrate that the performance of the VMs and virtual networks is satisfactory and that this system can improve the test efficiency and reduce test costs through rapid virtual resource provision and convenient test services.