• Proceedings of the Optical Society of Korea Conference
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• 2007.02a
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• pp.147-148
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• 2007

• Journal of Digital Contents Society
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• v.9 no.2
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• pp.349-356
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• 2008

MMORPG which offers a utopian world that includes a different rule from the real to satisfy players' needs for escape from the real world has changed. In these days, MMORPGs which have a unique world than middle-age fantasy have appeared as a new experience field. This paper compares MMORPGs have a middle-aged fantasy background story like J.R.R. Tolkein with another types bases on fantasy theory and presents difference.

• The KSFM Journal of Fluid Machinery
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• v.1 no.1 s.1
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• pp.58-63
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• 1998

To investigate turbine flow fields under realistic conditions, a rotating turbine test facility has been developed at the Inha University Propulsion Laboratory. The experimental facility consists of an air inlet, settling chamber, single turbine stage test section, and diffuser. This turbine has a design flow coefficient of 0.55 and work coefficient of 1.88. The turbine test rig has four features. First, a large scale test section improves space resolution. Second, low speed rpm enhances safety and reduces required power, Third, DC motor/generator is able to regenerate blower power. Fourth, various types of experiment can be carried out.

• Proceedings of the Acoustical Society of Korea Conference
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• 1996.06a
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• pp.9-12
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• 1996

This paper introduces an analysis of the non-axisymmetric mode due to in-plane vibration of an annular type piezoelectric actuator using FEM(Finite Element Method). The actuator is used as stator of ultrasonec motor. The freqrency charecterisrics and non-axisymmetric mode of the annular piezoelectric acruator are considered at a steady-state condition. The non-axisymmetric mode is occured by two sinusodial voltage sources with $\pi$/2 phase difference on the time domain. The resonant frequency of non-axisymmetric of non-axisymmetric mode is 60.358 kHz and 59.880 kHz for calculation and measurement, respectivly. The error was 0.8% between calculation and measurement. The revolution of the non-axisymmetric mode for actuator is analized at a period of exciting voltage sources using annimation. It is confirmed that the actuator has an usefulness as the stator of ultrasonic motor and the preposed method has a properity.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.12
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• pp.1979-1985
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• 2016

A protection algorithm using a voltage-controlled overcurrent element for a looped collection circuit in a wind farm is suggested in this paper. Because the proposed algorithm uses voltage relaying signals as well as current relaying signals, any fault in the looped collection circuit can be cleared by voltage-controlled overcurrent relays located at the two adjacent relaying points, the nearest place in each direction from the fault point. The algorithm can also distinguish the external faults which occur at the outside of a wind farm from the internal faults. It means that the proposed algorithm can provide the proper ability of protection coordination to the relays in the looped collection circuits of a large wind farm. The performance of the proposed algorithm is verified under various fault conditions using PSCAD/EMTDC simulations.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.11a
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• pp.367-370
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• 2007

Present study examines detonation wave propagation characteristics in annular channel. A normalized value of channel width to the annular radius was considered as a geometric parameter. A parametric study was carried out for a various regimes of detonation waves from weakly unstable to highly unstable detonation waves. Numerical approaches that used in the previous study of numerical requirements of the simulation of detonation wave propagations in 2D and 3D channel were used also for the present study with OpenMP parallization for multi-core SMP machines. The major effect of the curved geometry on the detonation wave propagation seems to be a flow compression effect, regardless of the detonation regimes. The flow compression behind the detonation wave by the curved geometry of the circular channel pushes the detonation wave front and results in the overdriven detonation waves with increased detonation speed beyond the Chapmann-Jouguet speed. This effect gets stronger as the normalized radius smaller, as expected. The effect seems to be negligible beyond the normalized radius of 10.

• Korean Architects
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• no.3 s.407
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• pp.81-85
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• 2003

새로운 정부에 걸맞는 에너지 절약형 희망도시를 찾아보려 노력한 결과 직접 방문하지는 않았지만, 박용남 선생의 '꿈의 도시 꾸리찌바'를 통해 가능성을 찾을 수 있었다. 이명박 서울시장이 이곳을 방문하여 그곳 시장과 교류활성화에 합의하였다는 소식을 접하고 용기를 내어 관련자료들을 모아 간략하게나마 소개하고자 한다. 희망의 도시 쿠리치바를 능가하는 길은 세계적인 월드컵을 성공리에 이루어 낸 대한민국이라면 결코 어렵지도 않고 불가능하지도 않다. 이 시점에서 우리들에게 필요한 것은 기존의 잘못된 진보에 대한 환상을 과감히 버리고, 늦었지만 이제 새롭게 시작하자는 것이다. 다음의 몇 가지 중요한 글과 사진은 공공의 계몽이라는 명제아래 박용남 선생의 저서에서 퍼온 것임을 밝힌다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.217-222
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• 2006

Internal combustion engine is the main source of environmental pollutants and therefore advanced technology is required to reduce harmful elements from the exhaust gases all over the world. Especially, when the exhaust gas is released front the automotive muffler, exhaust noise has many bad influence on the surrounding environment. In order to reduce the exhaust noise, it is necessary that automotive muffler must be designed for best exhaust efficiency. The sound insulation room was installed for the analysis of an acoustics characteristics of the noise from automotive muffler, in this study. Exhaust gas noise, noise distribution characteristics, pressure and temperature of exhaust gas were investigated with the change of annulus temperature of air cooled annulus automotive muffler and cooled annulus automotive muffler. The following results were obtained with this study. From the frequency analysis of automotive muffler, high noise distribution was observed in the range $100{\sim}2000Hz$. It means that the noise in this range has an dominate influence for the overall noise. Noise reduction of automotive muffler was affected by the temperature of annulus. It is caused the result that the high temperature and pressure of exhaust gas are changed lower by the drop of annulus temperature. The tendencies of noise, the temperature and pressure of exhaust gas are similar to the performance curve of engine. Exhaust gas pressure is determined by the r.p.m. of engine and affected by the cooling performance of automotive muffler.

• Journal of TMJ Balancing Medicine
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• v.8 no.1
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• pp.24-29
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• 2018

Objectives: The purpose of this study was to report the effect of Postural Yinyang Correction of the Temporomandibular joint (Functional Cerebrospinal Therapy, FCST) for phantogeusia. Methods: A patient with phantogeusia was treated at the Department of Acupuncture & Moxibustion, Dong-Eui University Korean Medicine Hospital from Oct 10th, 2018 to Dec 4th, 2018. A patient received 24 times of FCST with Customized TMJ Balancing Intraoral Appliance, upper cervical manipulation. To estimate the efficacy, Visual Analogue Scale (VAS), Oral Health Impact Profile-14 (OHIP-14) and questionnaire. Results: The patient showed a certain degree of improvement in phantogeusia and other subject symtoms within 8 weeks. Adverse effects were not reported. Conclusions: These results showed that FCST using an Customized TMJ Balancing Intraoral Appliance, may be useful for reducing the symptoms of phantogeusia.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1986.06a
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• pp.26-29
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• 1986

회전축계의 강제진동으로 가장 전형적이고 공업상 중요한 것은 넓은 의미로서 불평형 진동이다. 불평형은 회전체의 제작상 피할 수 없으며 진동이 전혀 문제가 되지 않는 정도로 제작하는 것은 경제적인 면에서도 불가능하다. 지금까지 미끄럼 베어링으로 지지된 회전축계의 불평형 응답 특성에 대하여는 여러 연구자에 의해 연구가 진행되고 있다. 수중에서 운전되는 펌프는 물의 감쇠작용 때문에 축진동 문제는 적다고 생각되어 펌프의 축진동에 관한 보고는 별로 없다. Black은 펌프의 축진동을 연구하여, 시일부분이 축진동 응답에 큰 영향을 미치는 것을 보였다. 그러나 시일형상에 따른 유체력 평가가 충분히 구명되지 않았기 때문에 환상 시일부분의 틈새,폭경비 및 압력차 등이 펌프진동에 어느 정도 영향을 미치는가가 충분히 검토 되어 있지않다. 이에 저자는 펌프용 시일의 유체력에 의한 진동 특성에 관한 일련의 연구를 진행하여 각종 시일의 유체력을 해석하였고, 이 유체력이 회전축계의 안정성에 미치는 영향을 검토하였으며 범용 안정성해석 프로그램을 개발하였다.