• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.237-240
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• 2003

This paper reports the characteristics of TFTs, formed inside a location-controlled grain: "single-crystalline" Si TFTs (c-Si TFTs). Position of the grains were controlled with a great precision by "${\mu}-Czochralski$ (grain-filter) process". Effects of process parameters, such as, deposition method of gate $SiO_2$, crystallization energy density and position of the channel with respect to the grain filters on TFT characteristics is investigated. It is concluded that the characteristics of TFTs drastically improved by avoiding the grain filter from the channel region. With TFTs having the current-flow direction parallel to radial direction from the grain-filter, electron mobility and subthreshold swing of 600 $cm^2/Vs$ and 0.21 V/dec. respectively are obtained.

• Journal of Information Technology Applications and Management
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• v.20 no.4
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• pp.315-338
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• 2013

As a result of New media that affects the marketing system, it is appeared a new marketing system called Market Platform in terms of market governance of trading. Market Platform is a new marketing system for ideal market system through the community structure from a hierarchy structure. It is determined that Market Platform as the role of adjustment of each side of market, buyer and seller, developed an existing marketing system. In this study, to target the Market Platform has recently emerged as the center of the market management in the new media environment. This study investigates what characteristics and impact of infrastructure of Market Platform will affect the cognitive impact on both buyers and sellers to clarify the impact on the self efficacy of the shopping process. Through this investigation, modeling for the impact that new media environment will attract Market Platform will be developed from the investigation of attractiveness of mobile market platform environment. Changes in the technical media environment gave the characteristics of the customer in the market platform, so consumers could involve not only consumed, but also manufactured. Thus, it is possible to increase the attractiveness if market must be able to not only for the convenience of shopping, but also make people to enjoy the experience of value co-creation. In other words, the new media, as a result of affecting the marketing system, mobile market platform is organized around the market of communication base. Network centrality, visible openness, ubiquitous multiplexity, 3 properties of new media increase the market self-efficacy of their customers. Therefore, the structure of market platform that enhance self-efficacy has higher attractiveness.

• The Journal of the Korea Contents Association
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• v.22 no.6
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• pp.342-353
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• 2022

This study aims to help revitalize the real-time online education platform market by analyzing the instructor characteristics, content characteristics, and platform characteristics of real-time online education platforms for local learners in China. A total of 670 questionnaires were collected through an online survey and an empirical analysis was conducted. As a result of the analysis, first, except for attractiveness, which is the characteristic of the instructor, professionalism and sincerity had a significant positive influence on both learning satisfaction. Second, the usefulness, abundance, and appropriateness of content characteristics had a significant positive influence on learning satisfaction. Third, except for interaction, which is a platform characteristic, technology and convenience confirmed a significant positive influence relationship on both learning satisfaction. Fourth, learning satisfaction had a significant positive effect on the intention to continue using. This study presented practical implications for real-time online education platform and future research directions.

• The Journal of Information Systems
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• v.31 no.2
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• pp.111-136
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• 2022

Purpose The purpose of this study is to examine the effect that insecurity and autonomy of platform work have an influence on work-life balance and psychological well-being in an era of platform economy based on two characteristics of online platform work and self-determination theory. Design/methodology/approach This study suggested the structural equation model integrating two antecedents, insecurity and autonomy, work-life balance, and psychological well-being and proposed five hypotheses driven from the research model. A total of 334 valid samples were collected from platform workers by employing questionnaire including 24 question items of four constructs. Findings Three hypotheses were supported and one hypothesis was not supported at the significance level of 0.05. Insecurity of platform work has a negative influence on work-life balance at the significance level of 0.01, whereas insecurity of platform work has no a significant influence on psychological well-being. Autonomy of platform work has a positive influence on both work-life balance and psychological well-being at the significance level of 0.01. Work-life balance has a positive impact on psychological well-being at the significance level of 0.001. Insecurity have an influence on psychological well-being indirectly through mediation of work-life balance. Implications for academicians and practitioners were suggested.

• Journal of Information Technology Services
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• v.21 no.5
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• pp.15-28
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• 2022

Recently, government agencies are actively adopting the platform model as a means of public policy. However, existing studies on the public platform are minimal and have focused on user experiences or the possibility of public usage of the platform model. Now the research concerning building governance structure and utilizing network effects of the platform after adopting the platform model in the public sector is keenly required. This study intended to ignite academic dialogue on the governance of public platforms in the context of digital transformation. This study focused on a case of the 'Special delivery,' a public delivery app established by Gyeonggi-do. In order to analyze the characteristics of the public platform and its governance structure, data were collected from press releases, policy reports, and news articles. Data was analyzed using the frame of Hagui's platform design factors and Ansell & Gash's collaborative governance model. The results of the public platform analyses showed 1) incompleteness in the value trade-off accounting, which was designed for platform business based on general cost-benefit analysis, and 2) a closed governance structure that limits direct participation of diverse user groups(i.e., service provider, customer) in order to enhance providers' utility by preventing customers' excessive online activities. The results of this study provided theoretical and policy implications regarding designing the strategy for accounting for value trade-offs and functioning governance structure for public platforms.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11a
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• pp.235-240
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• 2001

A four degrees of freedom (dof) motion platform for bicycle simulator is developed. The motion platform, capable of the vertical linear and three angular motions, is designed based on analysis of the typical motion characteristics revealed by the existing six dof bicycle simulator. The platform essentially consists of two parts： the three dof parallel manipulator, consisting of a moving platform, a fixed base and three actuators, and the turntable to generate the yaw motion. The nonlinear kinematics and dynamics of the three dof parallel manipulator with multiple closed loop chains are analyzed for tracking control of the motion platform. The tracking performances of the three control schemes are experimentally compared： the computed torque method (CTM), the sliding mode control (SMC) and the PD control. The CTM and SMC, incorporated with the system dynamics model, are found to be equally better in performance than the PD controller, irrespective of the presence of external disturbance.

• Laser Solutions
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• v.14 no.1
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• pp.6-13
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• 2011

Manufacturing technology platform for automotive and mobile industries has been constructed since 2009, for the platform technology project funded by ministry of knowledge and economics. Technology platform in laser welding has also been developed for automotive steel sheets with a strength up to 1GPa. Laser welding technology platform will provide welding characteristics for various laser sources, steel plates and welding conditions. This article shortly explains outline of laser welding technology platform and partially introduces the developed laser welding data base.

• The Journal of the Acoustical Society of Korea
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• v.40 no.6
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• pp.615-625
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• 2021

Prior to proposing appropriate standard for subway station platform, this study conducted field measurements to examine characteristics of room acoustics on platform of two subway stations. As a result of analyzing the longitudinal length of the platform, Sound Pressure Level (SPL) decreased (maximum difference : 14 dB), Reverberation Time (RT) tended to increase (maximum difference of 0.8 s ~ 1.5 s), and C50 and D50 were decreased (maximum difference: 5.9 dB ~ 9.1 dB and 31.8 % ~ 37.6 %, respectively) as measurement positions moved away from the sound source. The Interaural Cross-correlation Coefficient (IACC) did not show clear tendency, but it was lower than 0.3 in entire points. It is judged that the subway platform has non-uniform sound field characteristics due to various combinations of direct and reflective sound even though it is finished with a strong reflective material.This indicates that the room acoustic characteristics of the near and far sound field are clearly expressed depending on the source-receiver distances in the subway platform having a long flat shape with a low height compared to the length.Therefore, detailed architectural and electric acoustic design based on the characteristics of each location of speaker and sound receiver in the platform is required for an acoustic design with clear sound information at all positions of the platform.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.8 s.173
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• pp.118-127
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• 2005

A spatial 3 degrees-of-freedom mechanism employing Stewart Platform structure is proposed: the mechanism maintains the 3- RRPS structure of Stewart Platform but has an additional passive PRR serial sub-chain at the center area of the mechanism in order to constrain the output motion of the mechanism within the output motion space of the added PRR serial subchain. The forward and reverse position analyses of the mechanism are performed. Then the mechanism having both the forward and the reverse closed-form solutions is suggested and its closed form solutions are derived. It is confirmed, through the kinematic analysis of those two proposed mechanisms via kinematic isotropic index, that both the proposed mechanisms have fairly good kinematic characteristics compared to the existing spatial 3-DOF mechanisms in literature.

• Journal of KSNVE
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• v.9 no.1
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• pp.49-59
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• 1999

The mechanism of Stewart platform has many advantages for kinematic analysis and control. Thus there have been many research about employing this mechanism in the new type of machine tool. Since the vibration caused during the manufacturing process has a severely adverse effect on the machining precision. it is very important to enhance the vibrational characteristics. However. it is not easy to use finite element model for the vibration analysis. That is because the vibration behaviors of the structure vary in a complicated manner according as the length of links varies. In this paper, a Stewart platform type of machine tool is modeled in finite element method and then updated by using the experimental modal data. Finally. the static and dynamic characteristics of the finite element model are predicted and then discussed.