• Journal of the Korean Institute of Gas
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• v.21 no.5
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• pp.89-94
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• 2017

The VR(Virtuality Reality) technology provides very close experience to reality by stimulating humans' external recognition with artificial technologies. In order to overcome the limitation of real-environment training, VR is being applied in industry field as a key technology to prevent safety accident and its control procedure training. However, it is difficult to build VR-based training system because 3D modeling and software coding are necessary for materialization of VR environment demands of many development resource. In this research referring to VR based training content implementation, a method to utilizing VRDC(VR-based Dynamic visualization Component) is suggested and by applying it to plant safety training system, it was confirmed its practicality.

• Journal of KIISE:Computer Systems and Theory
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• v.33 no.12
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• pp.867-879
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• 2006

This paper concerns fast and time accurate HW/SW cosimulation for MPSoC(Multi-Processor System-on-chip) architecture where multiple software and/or hardware components exist. It is becoming more and more common to use MPSoC architecture to design complex embedded systems. In cosimulation of such architecture, as the number of the component simulators participating in the cosimulation increases, the time synchronization overhead among simulators increases, thereby resulting in low overall cosimulation performance. Although SystemC cosimulation frameworks show high cosimulation performance, it is in inverse proportion to the number of simulators. In this paper, we extend the novel technique, called virtual synchronization, which boosts cosimulation speed by reducing time synchronization overhead: (1) SystemC simulation is supported seamlessly in the virtual synchronization framework without requiring the modification on SystemC kernel (2) Parallel execution of component simulators with virtual synchronization is supported. We compared the performance and accuracy of the proposed parallel SystemC cosimulation framework with MaxSim, a well-known commercial SystemC cosimulation framework, and the proposed one showed 11 times faster performance for H.263 decoder example, while the accuracy was maintained below 5%.

• Asia pacific journal of information systems
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• v.22 no.2
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• pp.39-69
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• 2012

With the advent of communication technologies including electronic collaborative tools and conferencing systems provided over the Internet, virtual collaboration is becoming increasingly common in organizations. Virtual collaboration refers to an environment in which the people working together are interdependent in their tasks, share responsibility for outcomes, are geographically dispersed, and rely on mediated rather than face-to face, communication to produce an outcome. Research suggests that new sets of individual skill, knowledge, and ability (SKAs) are required to perform effectively in today's virtualized workplace, which is labeled as individual virtual competence. It is also argued that use of online social networking sites may influence not only individuals' daily lives but also their capability to manage their work-related relationships in organizations, which in turn leads to better performance. The existing research regarding (1) the relationship between virtual competence and task performance and (2) the relationship between online networking and task performance has been conducted based on different theoretical perspectives so that little is known about how online social networking and virtual competence interplay to predict individuals' task performance. To fill this gap, this study raises the following research questions: (1) What is the individual virtual competence required for better adjustment to the virtual collaboration environment? (2) How does online networking via diverse social network service sites influence individuals' task performance in organizations? (3) How do the joint effects of individual virtual competence and online networking influence task performance? To address these research questions, we first draw on the prior literature and derive four dimensions of individual virtual competence that are related with an individual's self-concept, knowledge and ability. Computer self-efficacy is defined as the extent to which an individual beliefs in his or her ability to use computer technology broadly. Remotework self-efficacy is defined as the extent to which an individual beliefs in his or her ability to work and perform joint tasks with others in virtual settings. Virtual media skill is defined as the degree of confidence of individuals to function in their work role without face-to-face interactions. Virtual social skill is an individual's skill level in using technologies to communicate in virtual settings to their full potential. It should be noted that the concept of virtual social skill is different from the self-efficacy and captures an individual's cognition-based ability to build social relationships with others in virtual settings. Next, we discuss how online networking influences both individual virtual competence and task performance based on the social network theory and the social learning theory. We argue that online networking may enhance individuals' capability in expanding their social networks with low costs. We also argue that online networking may enable individuals to learn the necessary skills regarding how they use technological functions, communicate with others, and share information and make social relations using the technical functions provided by electronic media, consequently increasing individual virtual competence. To examine the relationships among online networking, virtual competence, and task performance, we developed research models (the mediation, interaction, and additive models, respectively) by integrating the social network theory and the social learning theory. Using data from 112 employees of a virtualized company, we tested the proposed research models. The results of analysis partly support the mediation model in that online social networking positively influences individuals' computer self-efficacy, virtual social skill, and virtual media skill, which are key predictors of individuals' task performance. Furthermore, the results of the analysis partly support the interaction model in that the level of remotework self-efficacy moderates the relationship between online social networking and task performance. The results paint a picture of people adjusting to virtual collaboration that constrains and enables their task performance. This study contributes to research and practice. First, we suggest a shift of research focus to the individual level when examining virtual phenomena and theorize that online social networking can enhance individual virtual competence in some aspects. Second, we replicate and advance the prior competence literature by linking each component of virtual competence and objective task performance. The results of this study provide useful insights into how human resource responsibilities assess employees' weakness and strength when they organize virtualized groups or projects. Furthermore, it provides managers with insights into the kinds of development or training programs that they can engage in with their employees to advance their ability to undertake virtual work.

• Journal of Korea Multimedia Society
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• v.15 no.11
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• pp.1399-1408
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• 2012

The light source is an important visual component that empirically affects the color and illumination of graphic objects, and it is necessary to precisely store and appropriately employ the information of all light sources in the real world in order to obtain photo-realistic composition results. The information of real light sources can be accurately stored in HDR environment maps; however, it is impossible to create new environment maps corresponding to dynamic virtual light sources from a single HDR environment map captured under a fixed lighting situation. In this paper, we present a technique to dynamically generate well-matched information for arbitrarily selected virtual light sources using HDR environment maps created under predefined lighting position and orientation. Using the information obtained from light intensity and distribution analysis, our technique automatically generates HDR environment maps for virtual light sources via image interpolation. By applying the interpolated environment maps to an image-based lighting technique, we show that virtual light can create photo-realistically rendered images for graphic models.

• Journal of KIISE:Computing Practices and Letters
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• v.15 no.6
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• pp.454-458
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• 2009

The technology of virtual environments has been developed with better-quality appearance on a computer display in mind, but without consideration for objects' precise measurements in physical units. With the increased application of computer graphics in a variety of areas, there is a need for precise measurement functionality in addition to visualization. This paper describes the definition of physical properties using measurement units for X3D based virtual objects, to provide their precise physical information in virtual environments. To this end, we have included the physical property node in the X3D specification. The physical measurement units, such as length, mass, time, temperature, etc., are based on SI units (International System of Units).

• Journal of the Korea Fashion and Costume Design Association
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• v.23 no.3
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• pp.11-21
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• 2021

Virtual reality is currently mainly used in games, but is starting to be applied as a variety of media fields, such as broadcasting and film. Virtual reality provides more fun than reality, and can provide new experiences in areas that cannot be experienced in reality due to the constraints of time, space, and environment. In particular, as the social non-contact arena has increased due to COVID-19, it is being applied to education, health, and medical industries. The contents are further expanding into design and military fields. Therefore, the purpose of this study was to observe the change in distribution of load and pressure felt by the body in the flying state while wearing a short pants harness, which are mainly used in the game and entertainment industry. In the experiment, the average pressure in the flying state was measured by attaching a pressure sensor to the back and front of a human mannequin. As a result, it was confirmed that the load concentrated on the waist in the flying state was 44 N, with a pressure of 1353 kPa. The pressure distribution was concentrated in front of the center of gravity, and was measured was at 98% by the pressure sensors, with an average pressure value of approximately 15 kPa, and a pressure value of approximately 12 kPa at the back, which was measured at 67% by the pressure sensor. The results of the load and pressure distribution measurement are presented as fundamental data to improve the wearability and comfort of harnesses in the future, and are compared to actual measured pressure values by analyzing the clothing pressure in flight through virtual wear of harnesses through the CLO 3D program.

• The Transactions of the Korean Institute of Power Electronics
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• v.22 no.6
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• pp.496-503
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• 2017

This study proposes a high-performance current control algorithm for a diode-bridge-type single-phase boost power factor correction (PFC) converter. The conventional asynchronous single-phase current controllers that directly control AC-type current tend to be accompanied by steady-state errors due to their poor dynamic characteristics for the transient-state, which can be attributed to bandwidth limitations and phase delays. In the proposed algorithm, an ideal current control with minimal phase delays and steady-state errors can be achieved by using a virtual DQ synchronous reference frame and by controlling the synchronous reference frame excluding the frequency component in the single-phase system. The performance of the conventional asynchronous single-phase current controller is compared with that of the proposed algorithm through simulation and experiments, and the results have confirmed the superiority of the latter.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2039-2044
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• 2003

The advanced infrastructure for accelerating the development of personal robots is presented. Based on this structure, effective ways for integrating the various commercial components and interfacing among them are studied. The infrastructure includes the technology such as modularization based on independent processing and standardization open to other developers. The infrastructure supports not only that each hardware component of a personal robot can be easily attached to and detached from the whole system mechanically but also that each software of the components can be functionally distributed. As a result, we developed the fully modularized personal robots mechanically, and a virtual machine for the control of these robots. In this paper the proposed infrastructure and its implementations are described.

• Korean Institute of Interior Design Journal
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• v.16 no.2 s.61
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• pp.314-321
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• 2007

The statistical method of human sensibility ergonomics is widely used for analyzing interior design because it has standard processes and it can help to get quantifiable results. However applying this method demands repeated intense work and great time and effort is required. In this study, a tool applying Web and virtual reality techniques for statistical human sensibility ergonomic interior design analysis is proposed and the key parts of the tool including database and interface are implemented. The database contains the sensibility adjective table and the physical interior design factor table for analyzing the relationship between human sense and physical design factors. Interface of the tool is implemented using Web technologies, so testers can evaluate interior design samples via standard Web browsers. The 3D control which is an important component of the interface is also implemented. Employing the suggested tool can reduce effort and time for evaluating human sense in Interior design field.

• Journal of Applied Reliability
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• v.12 no.3
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• pp.187-199
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• 2012

In general, accelerated life testing is performed to reduce testing time. But it is difficult to apply accelerated life testing to a system besides components. This paper developed a software which estimates reliability measures of the system from results of accelerated life testing of components building the system. This software can handle the system with a large number of components and complex topology. Multiple failure modes of a component were also considered in this software. Based on the software, reliability measures of a gearbox example at several conditions were estimated from the accelerated life testing results of three components of the gearbox.