• Journal of the Korea Computer Graphics Society
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• v.27 no.3
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• pp.43-53
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• 2021

This paper presents an interactive wind system that generates artificial winds in a virtual reality (VR) environment according to online user inputs from a steering wheel and an acceleration pedal. Our system is composed of a head-mounted display (HMD) and three electric fans to make the user sense touch from the winds blowing from three different directions in a racing car VR application. To evaluate the effectiveness of the winds for reducing VR cybersickness, we employ the simulator sickness questionnaire (SSQ), which is one of the most common measures for cybersickness. We conducted experiments on 13 subjects for the racing car contents first with the winds and then without them or vice versa. Our results showed that the VR contents with the artificial winds clearly reduce cybersickness while providing a positive user experience.

• Journal of Mechanical Science and Technology
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• v.17 no.2
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• pp.221-229
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• 2003

In the virtual environment, reality can be enhanced by offering the motion based on a motion simulator in harmony with visual and auditory modalities. In this research the Stewart-Gough-platform-based motion simulator has been developed. Implementation of vehicle dynamics is necessary in the motion simulator for realistic sense of motion, so bicycle dynamics is adopted in this research. In order to compensate for the limited range of the motion simulator compared with the real vehicle motion, washout algorithm composed of high-pass filter, low-pass filter and tilt coordination is usually employed. Generally, the washout algorithm is used with fixed parameters. In this research a new approach is proposed to tune the filter parameters based on fuzzy logic in real-time. The cutoff frequencies of the filters are adjusted according to the workspace margins and driving conditions. It is shown that the washout filter with the fuzzy-based parameters presents better performance than that with the fixed ones.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1996.06b
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• pp.23-28
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• 1996

Model-based coding is one of several approaches to very low bit rate image coding and it can be used in many applications such as image creation and virtual reality. However, its analysis and synthesis processes remain difficult, especially in the sense that the resulting synthesized image reveals some degradation in detailed facial components such as furrows around eyes and mouth. To solve the problem, a large number of methods have been proposed and the texture update method is one of them. In this paper, we investigate texture synthesis for model-based coding. In the update process of the proposed texture synthesis algorithm, texture information is stored in a memory and the decoder reuses it. With this method, the transmission bit rate for texture data can be reduced compared with the conventional method updating texture periodically.

• 한국HCI학회:학술대회논문집
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• 2006.02b
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• pp.156-162
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• 2006

It was hypothesized that mobile 3D provide the sense of presence in different quantity and quality aspects in virtual reality. And it was supposed that the construction of presence involves various levels and dimensions. The factors of mobile 3D game are divided into 4 super-factors; condition factor, interface factor, attention factor, feedback factor that resulted into 20 sub-factors resulted from the factor analysis. Our primary goal is the development of valid Mobile 3D presence scale, and to find out the factor structure of the scale.

• Journal of Digital Contents Society
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• v.18 no.2
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• pp.283-291
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• 2017

Though new body movement based input system immerged in Virtual Reality (VR), VR still has a visually induced motion sickness (VIMS) problem to be accepted for users. VIMS are caused by changes in visually perceived movement that discord with vestibular system's sense of movement. Not only Head-body movements, but also hand gestures to make commands and torso movement can affect visual movement perception by enhancing immersion and its psychological product; presence. The question arises does whole body movement and hand gesture to make commands are more dominant to arousal, presence, and VIMS? To address this question, we conducted "2 (IV1; head-body movements only vs. whole body movements) * 1" between subject design experiment. The results showed that significant effect on whole body movements and arousal, marginally significant effect on presence. Eyewear usage was a moderator between hand gesture and presence relationship.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2687-2692
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• 2003

Recent advancement in information technology requires new interpretations for the space among human, machines and environment. Investigation of space between information and human could lead to the proper ways, in which human and machines meet. Various concepts regarding space have been explored in terms of “virtual reality in cyberspace” and “embodiment in tangible space.” “Mom (embodiment),” space, virtuality, sensation/perception, and interactive technology are some of the key ideas to be explored. Human “Mom” is such a fundamental membrane through which human can interact with the environment physically and mentally. An embodied interaction paradigm, based on “Mom,” is investigated. This leads to interactive technology paradigm. Sound space is an invisible but a tangible space in a sense that it travels in emotional tremors and stimulates new sensations and perceptions. Three cases are introduced to experiment such tangible space as a new and proper interactive paradigm. Also, a historical model of interaction is reviewed, which includes electrical, symbolic, textual, graphical, tangible, and social interaction.

• The Journal of the Korea Contents Association
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• v.6 no.11
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• pp.182-189
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• 2006

Consumers can choose suitable shoes for their feet in off-line shopping. However, in on-line shopping, because they can not wear shoes, compare to the off-line shopping, there are many problems in internet shopping. And the solution of user-oriented internet shopping is development of new type of prototype which is accessible to user and to offer visual information through 3D-virtual reality. We made this Prototype that the consumer can measure their own shoes size. And the consumer can print out their foot size in the internet database and measure their own foot size and type. And we maximized the visual experience though it is indirect and then we wanted to overcome a emotional experience in the real world. we visualized first, 'the softness' of shoes meterial, second 'the drainage' in the realtion of shoes meterial and water, third 'the close adhesion' in the realtion of shoes and consumer's their own foot and last 'the elasticity' in the relation of the shoes outer sole and surface. The result of this research can solve the problem in the existing on-line shoes' shop and it will become an alternative plan. And this prototype just will not become the localization at the on-line shoes' shop. In true sense, it will be an important example in the whole internet industry.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.12
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• pp.161-168
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• 2016

Thanks to mass production and provision of smartphones and the HMD (head mounted display), VR (virtual reality) is now being applied to various areas. The VR HMD is the interface equipment which allows users to have realistic experiences through human sensory organs such as vision and auditory sense. Since the majority of VR equipment is operated by the display for both eyes, 360-degree video content and the depth information, the VR mechanism is closely related to human senses, especially vision. Previous studies have focused on how to minimize negative impact such as motion sickness or visual fatigue. Little attention has been paid on research about the visual treatment. Therefore, the focus of this study is to develop technical elements for utilization of vision therapy with the VR HMD and explore possible areas to apply it. To this end, we analyzed the past case studies and technical elements to identify 16 areas for vision therapy. We also developed the optical parameters for utilization of the VR HMD visual targets. The result of this study is expected to be utilized for development of visual targets for vision therapy based on the VR HMD.

• The Journal of the Acoustical Society of Korea
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• v.21 no.4
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• pp.339-438
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• 2002

This paper presents a method to simulate noise propagation by a computer for outdoor environment. Sound propagated in 3 dimensional space generates reflected waves whenever it hits boundary surfaces. If a receiver is away from a sound source, it receives multiple sound waves which are reflected from various boundary surfaces in space. The algorithm being developed in this paper is based on a ray sound theory. If we get 3 dimensional geometry input as well as sound sources, we can compute sound effects all over the boundary surfaces. In this paper, we present two approaches to compute sound: the first approach, called forward tracing, traces sounds forwards from sound sources. while the second approach, called geometry based computation, computes possible propagation routes between sources and receivers. We compare two approaches and suggest the geometry based sound computation for outdoor simulation. Also this approach is very efficient in the sense we can save computational time compared to the forward sound tracing. Sound due to impulse-response is governed by physical environments. When a sound source waveform and numerically computed impulse in time is convoluted, the result generates a synthetic sound. This technique can be easily generalized to synthesize realistic stereo sounds for virtual reality, while the simulation result is visualized using VRML.

• Korean Journal of Construction Engineering and Management
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• v.22 no.1
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• pp.3-12
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• 2021

In the remodeling projects, clients without architectural expertise have limitations in presenting requirements accurately. In some cases, designers and contractors may not recognize their demands exactly, and deliver final products that are different from the clients' intentions. 3D modeling visualizing final products in previous has been regarded as a solution to enhance understanding and communication. However, this approach has the limitation that the final results are presented as a virtual outputs. In the remodeling project, an alternative, mixed-reality, is likely to reinforce the reality as it enables to present remain structure and the parts to be built together. This paper examines the mixed reality as a solution to support decision making of clients and practitioners in remodeling projects. The examinations is conducted in high-rise office remodeling projects by means of action-research. Clients and practitioners, overview product models presented in the format of 2D drawings, BIM and mixed reality asked to evaluate the effectiveness of each methods in 12 standards. The results have shown that mixed reality has improved the sense of reality, making it easier to predict results, but recognizing patterns is difficult in some areas such as the floor, and it caused dizziness.