• Journal of Power Electronics
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• v.16 no.3
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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.

• Journal of Korea Multimedia Society
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• v.12 no.10
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• pp.1466-1477
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• 2009

With development of 3D virtual space technology, diverse studies on 3D virtual space are being conducted because virtual space is being recognized as an appropriate technology for the field of urban and architectural design. However, while the process of urban and architectural design is done based on collaboration of various interested parties, there is lack of studies that support such collaboration. Communication within the virtual space must be provided for 3D virtual space to support collaboration, and a quick and direct technique of expressing one's intentions is required. sketch technique is effective. Ambiguous lines of sketch are extremely effective in that the range of thoughts in the idea stage can be broadened. However, such traditional sketch technique alone is difficult to support collaboration in 3D virtual space. That is because diverse shapes of 3D space require input of sketch. Accordingly in this study, sketch annotation that can effectively deliver intentions in 3D space was studied. Annotation technique using sketch-box was examined.

• Korean Institute of Interior Design Journal
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• v.14 no.4 s.51
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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.

• Korean journal of communication and information
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• v.37
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• pp.342-376
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• 2007

This study attempted to explore relationship between self-identities in real space and in virtual space and to inspect empirically both self-identities' influence on addiction and society maladaptation of online role playing game users. The verified results through this study are summarized as follows. First, both self-identity in real space and self-identity in virtual space represent strong interrelationship. In detail, the user with strong self-identity in real space shows strong self-identity in virtual space. Second, self-identities in two spaces have the negative interrelationship with game addiction and maladaptation. Whether real space or virtual space, the higher self-identity, the lower the levels of game addiction and maladaptation. Especially, self-identity in real space appeared an influential variable determining the level of addiction and maladaptation. Although self-identity in virtual space have not an independent influence, it has the possibility to effect complementary with self-identity in real space. This fact means that virtual space is not the place where the user with weak self-identity in real space can discovers the ideal self. Because they also experience the negative recognition about oneself in virtual space.

• Journal of Digital Contents Society
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• v.19 no.2
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• pp.229-236
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• 2018

The background fort this study is related to the concept of modern time and space which has been extended from physical space to virtual space in the present times witnessing the advent of the Fourth Industrial Revolution. Based on visual tactility and illusion in virtual reality, we intended to present the possibility of the interactions as realistic as the interactions occurring in reality. Regarding the scope of this study, we analyzed the relationship between illusion in game space and immersion in interactions based on the games used frequently among current virtual reality contents. The results of the study showed that the interactions in virtual reality occurred within the space converging the time and space and that the illusion of digital images had realistic position of reality without original. Research which investigates the interaction in virtual space and media projection method for real space and virtual space will provide useful basis for promoting technological development based on novel methods differentiated from existing image grammar and for identifying the content utilization methods.

• Journal of Information Processing Systems
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• v.13 no.4
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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.

• IE interfaces
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• v.18 no.1
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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.

• Journal of the Korean Society of Clothing and Textiles
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• v.47 no.5
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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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• v.22 no.5
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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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• 2009.02a
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• pp.862-867
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• 2009

The development of internet has changed the realm of life from off-line to on-line, causing not only the overall change in society but also urgently demanding change in the basic concept of museum. Virtual Museums have appeared in line with such changes, and they utilize space regardless of real time and space unlike the traditional museums that collected and preserved works for exhibition in physical space thereby playing a role of catalyst for exhibition in virtual space and for direct exchange with the public. Through relevant literatures and case studies, the present research particularly investigated the exhibition characteristics of virtual reality-based museums out of all types of cyber museum, in an effort to make a comparison with those of offline museums, and eventually to suggest a direction of virtual reality museums that would be established in the future and to consider the possibilities of utilizing them.