• Journal of Power Electronics
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• 제16권3호
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• pp.946-959
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• 2016

A novel Virtual Space Vector (VSV) modulation strategy for complete control of potential neutral point (NP) issues is proposed in this paper. The neutral point potential balancing problems of multi-level converters, which include elimination of low frequency oscillations and self-balancing for NP dc unbalance, are investigated first. Then a set of improved virtual space vectors with dynamic adjustment factors are introduced and a multi-objective optimization algorithm which aims to optimize these adjustment factors is presented in this paper. The improved virtual space vectors and the multi-objective optimization algorithm constitute the novel Virtual Space Vector modulation. The proposed novel Virtual Space Vector modulation can simultaneously recover NP dc unbalance and eliminate low frequency oscillations of the neutral point. Experiment results show that the proposed strategy has excellent performance, and that both of the neutral point potential issues can be solved.

• 한국멀티미디어학회논문지
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• 제12권10호
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• pp.1466-1477
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• 2009

3D 가상공간은 도시 및 건축 설계 분야에 매우 적합한 활용 기술로 인식되어 다양한 연구가 시도 되고 있다. 그러나 도시 및 건축 설계의 과정이 다양한 관계자들의 협업에 의해 이루어지는 반면, 이를 지원하는 연구는 아직 미흡한 상황이다. 3D 가상공간이 협업을 지원하기 위해서는 무엇보다 가상공간 내에 의사소통을 지원해야 하며, 이를 위해서는 빠르고 직접적인 의사 표현 기술을 필요로 한다. 이러한 의사 표현 방법으로는 Sketch 기법이 효과적이며, Sketch의 부 정확한 선은 협업과정의 아이디어 단계에서 사고의 폭을 넓혀줄 수 있다는 점에서도 매우 효과적인 표현 방식이다. 그러나 이러한 전통적인 Sketch 기법만으로는 사실상 3D 가상공간에서 협업을 지원하기 어렵다. Sketch 기법을 협업에 적용한 기존의 연구들이 있지만 주로 3D 가상공간에 Sketch Annotation을 입력하는 것에만 중점을 두고, 입력된 Sketch가 담고 있는 내용을 잘 전달할 수 있는 지에 대해선 고려하지 못하였다. 따라서 평면이 아닌 객체에는 Sketch Annotation 입력이 불가능하거나, 입력되더라도 그 내용전달이 어려운 경우가 발생한다. 이 논문에서는 3차원 공간에서도 효과적으로 의사를 전달 할 수 있도록, 어떠한 형태의 면에 대해서도 Sketch Annotation의 내용이 정확히 전달될 수 있는 Sketch-Box를 이용한 Annotation기법을 연구한다.

• 한국실내디자인학회논문집
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• 제14권4호
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• pp.122-133
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• 2005

This study could begin with the improvement of computer graphic technology The graphic technology is the standards of computer technology level and up-to-date technology intensive. Above all, the technology of virtual reality has developed rapidly and the development of the program has changed from professional one only for the experts to easy of access ones for the space designers. Moreover, the program which major internet user's can experience the virtual model has been made, as the development of virtual reality technology that is based on the web. These graphic technology and the development of the web helped to extract human experiences on the space design step. However, to find the meeting point with real recognition is not easy though the virtual reality technology develops. Because the real space is made up of various senses that people feel in their surroundings. But, this study was possible because most of the space recognition is based on the visual organ, even though it can't satisfy all sensible factors that we feel in reality. Therefore, the significant of this study is the standards and criteria of evaluation, the technological proposal, expecting to make more advanced alternative design than before.

• 한국언론정보학보
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• 제37권
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• pp.342-376
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• 2007

이 연구는 온라인 롤프레잉 게임 이용자가 현실공간과 가상공간에서 형성하는 자아정체감의 관계를 탐색하고, 그것이 온라인 게임중독과 현실부적응감에 미치는 영향을 경험적으로 검증하고자 했다. 분석결과 현실공간의 자아정체감과 가상공간의 자아정체감은 정적으로 높은 상관성을 보였다. 구체적으로 현실공간의 자아정체감이 높은 사람들은 가상공간에서도 높은 자아정체감을 보였다. 또한 두 공간의 자아정체감은 게임중독과 현실부적응감과도 매우 높은 상관성을 보였는데, 두 공간 모두 자아정체감이 높을수록 게임중독과 현실부적응감 수준은 낮아지는 것으로 나타났다. 그중에서도 현실공간의 자아정체감은 게임의 부정적 효과들, 즉 중독과 현실부적응감 수준을 결정하는 요인으로 나타났다. 가상공간의 자아정체감은 비록 독립적인 영향력을 발휘하지는 못했지만, 현실공간의 그것과 상호보완적으로 영향을 미칠 가능성을 보였다. 이것은 현실공간에서 자아정체감이 낮은 사람들에게 가상공간이 이상적인 자아를 발견하고 자신에 대해 긍정적인 인식을 발전시킬 수 있는 대안적인 공간으로 작용하지 못함을 의미한다. 중독에 이르고 현실부적응감 수준이 높은 사람들은 현실공간과 마찬가지로 가상공간에서의 자신에 대해서도 부정적으로 인식하기 때문이다.

• 디지털콘텐츠학회 논문지
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• 제19권2호
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• pp.229-236
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• 2018

본 연구는 근대적 시공간 개념이 물리적 공간에서 4차 산업혁명의 시대를 살고 있는 현재는 그 범위가 가상의 공간으로까지 확대 되었다. 이러한 가상현실의 공간적 특징을 시각적 촉각성과 환영성을 바탕으로 현실과 같은 상호작용의 가능성에 대해 제안 하고자 한다. 본 연구의 범위는 현재 가상현실 콘텐츠 중 활용도가 높은 게임의 공간에 대한 환영성과 상호작용성의 몰입 관계를 분석한다. 연구 결과는 가상현실의 상호작용은 시공간이 융합된 공간으로 디지털 이미지의 환영성은 원본이 없는 실재의 현실적 위치에 있다. 현실공간과 가상공간에 대한 매체 투영 방법과 함께 가상공간에 대한 상호작용에 대한 연구는 새로운 영상문법으로 콘텐츠 활용 방안을 모색하는 데 기여하게 될 것이다.

• Journal of Information Processing Systems
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• 제13권4호
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• pp.876-892
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• 2017

A virtual reality is a virtual space constructed by a computer that provides users the opportunity to indirectly experience a situation they have not experienced in real life through the realization of information for virtual environments. Various studies have been conducted to realize virtual reality, in which the user interface is a major factor in maximizing the sense of immersion and usability. However, most existing methods have disadvantages, such as costliness or being limited to the physical activity of the user due to the use of special devices attached to the user's body. This paper proposes a new type of interface that enables the user to apply their intentions and actions to the virtual space directly without special devices, and test content is introduced using the new system. Users can interact with the virtual space by throwing an object in the space; to do this, moving object detectors are produced using infrared sensors. In addition, the users can control the virtual space with their own postures. The method can heighten interest and concentration, increasing the sense of reality and immersion and maximizing user's physical experiences.

• 산업공학
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• 제18권1호
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• pp.82-87
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• 2005

Most of virtual reality systems ask users to control 3D objects or to navigate 3D world using 3D controllers. To maximize the human performance in the control, the design of virtual reality system and its input and output devices should be optimized. In this study, an experiment was designed to investigate the effects of three resolution factors of a virtual reality system on the human performance. Six subjects conducted the experiment for the factors; two frame rates, three spatial resolutions, and three pictorial contents. The result showed that the greater the spatial resolution was, the higher the human performance was. For the temporal resolution, fixed frame rate at 18 Hz was better than the varied maximized frame rate. For the pictorial contents, the virtual space with orientation cues marked the greatest performance than the other two conditions; the virtual space without any orientation cue and the virtual space like real world. These results could be applied for the design of virtual reality systems.

• 한국의류학회지
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• 제47권5호
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• pp.891-906
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• 2023

The essence of fashion brands' marketing with metaverse-based virtual spaces is to capture more potential consumers and boost the sales of companies' virtual and physical products. However, existing research has not fully addressed customer responses and behavioral outcomes regarding fashion virtual brand spaces. This study uses flow theory to address this gap and explores the factors that lead to the flow experience in virtual brand spaces. It also establishes the causal relationships between the flow experience, satisfaction with virtual spaces, the intention to purchase virtual products, and the intention to purchase actual products. We chose "Ralph Lauren World" of Ralph Lauren on Zepeto as the virtual brand space for this study and analyzed 239 valid data sets. We tested the hypotheses using structural equation modeling and bootstrapping for the mediation analyses. The findings indicate that the flow experience in virtual brand spaces positively and indirectly affects the purchase intention of virtual products via satisfaction with virtual brand spaces. In addition, virtual space satisfaction had an indirect, positive effect on actual product purchase intention through virtual product purchase intention. The research emphasizes that the purchase intention of virtual and actual products has a positive causal relationship.

• International Journal of Computer Science & Network Security
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• 제22권5호
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• pp.375-380
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• 2022

Virtual and augmented reality technologies provide access to learning materials and improve the organization of a modern library's media space. This article aims to identify the significance and role of virtual and augmented reality technologies in the modern library's media space organization. Methodology. The research uses a university library case study methodology to empirically investigate virtual and augmented reality technologies. Results. Virtual and augmented reality technologies provide research and improve learning outcomes by engaging students and learners with significant interest in such technologies. Libraries offer users the opportunity to create their VR content through available software. Students can test their VR content in the libraries' labs. Libraries support access to a variety of virtual and augmented reality content. The content is accessed using "virtual reality headsets" for viewing and workstations with "authoring software and loanable 360 cameras" for creating. The library lab is a space to support students' digital creativity and research through virtual and augmented reality. There are 3D Design Labs within the libraries as a medium to large group design learning spaces with virtual reality technology. Libraries form a media space where users can create videos, podcasts, portfolios, edit media, and book tours, and students and researchers can explore different scientific knowledge. In this way, technology ensures that risks in learning are minimized as opposed to hands-on seminars and classes.

• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2009년도 학술대회
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• pp.862-867
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• 2009

박물관의 개념을 새롭게 변화시키고 있는 가상현실 기반 박물관의 전시 특성을 분석하고, 분석 결과를 토대로 활용 가능성을 제시하고자 한다.