• KIPE Magazine
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• v.25 no.5
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• pp.60-65
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• 2020

• Proceedings of the KIPE Conference
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• 2011.07a
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• pp.522-523
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• 2011

독립부하가 존재하는 분산발전시스템에서 FRT 기능을 수행하는 경우, 계통의 이상전압이 인버터의 독립부하에 그대로 걸리게 되는 문제가 있다. 이에 따라 FRT 기능을 준수함과 동시에 독립부하에도 일정한 품질의 전압을 공급할 수 있는 전압보상기법이 제안된 바 있다. 이때 무효전류 주입에 의해 IGBT의 전류정격이 증가되는데 본 논문에서는 인버터의 정격 상승량 분석을 통하여 이에 맞는 스위치를 선정하고 인버터의 모델을 고려한 전압보상기법 제어기 설계 기법을 제안한다.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.442_443
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• 2009

A large wind farm should satisfy the requirements for a grid and accomplish the optimization of the wind farm system. In that point of view, the wind farm intertie protection system, which must consider the Fault Ride-Through (FRT) requirement for more reliable protection, should be improved. This paper proposes a modified distance relay suitable for protection of a wind farm intertie considering a FRT requirement. The frequency change is used to discriminate the intertie fault from a outside zone fault. The performance of the proposed algorithm is verified using a PSCAD/EMTDC simulator.

• Korean Journal of Optics and Photonics
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• v.8 no.2
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• pp.154-160
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• 1997

On the base of the fractional Fourier transform(FRT) which is known as a generalized form of the conventional Fourier transform, the fractional correlation has been implemented. Shift-variance property of the fraction correlation has been evaluated and compared with the shift-invariance of the conventional correlation. The fractional correlation operation has been implemented by using a planar optics configuration which integrates all of the optical components on a single glass substrate. A good agreement between the experimental and calculated results has been obtained.

• Journal of Korean Clinical Health Science
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• v.3 no.4
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• pp.490-494
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• 2015

Purpose. The purpose of this study was to evaluate the effects of calf muscle massage on the balance of low extremities and flexibility of both ankles. Methods. The subjects were 16 healthy adults(men 8, women 8). The group was applied effleurage, tapotement, pressure forms of massage on their calf muscles. The intervention was offered during 3 minutes per one leg, to a total of 6 minutes. We assessed their balance and flexibility of both ankles using Functional reaching test(FRT) and One leg standing test(OLST) with trampoline before and after applying massage. Results. In this study, the data shows the ability of FRT and the ability of OLST with trampoline is improved in massage group. Conclusions. These results suggest that massages help to improve the balance of low extremities and the flexibility of both ankles.

• Journal of Advanced Marine Engineering and Technology
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• v.19 no.4
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• pp.72-78
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• 1995

The diffusion of fuzzy logic techniques into real applications requires specific software supports which save development time and reduce the programming effort. But we has been lack of a tool devoted to support the design of fuzzy controllers. In this paper, on the basis of the general fuzzy set and .alpha.-cut set decomposition of fuzzy sets, a set of fuzzy reasoning tool(FRT) devoted to support the design of fuzzy dontroller for servo systems is developed. The major features of this tool are: 1) It supports users to analyze fuzzy ingerence status based on input deta and expected results by three-D graphic display. 2) It supports users to prepare input data and expected result. 3) It supports users to tuned scaling factor of membership functions, rules and fuzzy inference. The paper shows how the suggested design tools are suitable to give a consistent answer to the tuning of fuzzy control system. This FRT is expected to exert good performance and devoted to support which the design of fuzzy controller is illustrated in the servo systems.

• Proceedings of the KIPE Conference
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• 2010.07a
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• pp.322-323
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• 2010

본 논문은 2MW급 풍력시스템의 이중여자유도형 발전기(DFIG)를 제어하기 위한 PCS의 전력변환장치와 주변장치 및 제어기술에 대해서 기술한다. 최근 국내 뿐만 아니라 해외 전력회사에서는 계통전원 사고 시 풍력시스템이 계통연계를 유지하면서 계통의 전력품질에 기여할 수 있는 기능(FRT)을 요구하고 있다. FRT기능 구현을 위한 H/W와 제어 시퀀스를 소개한다.

• Proceedings of the Korea Contents Association Conference
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• 2013.05a
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• pp.223-224
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• 2013

이 연구는 뇌졸중환자를 대상으로 낙상예방을 위하여 오타고운동과 요부안정화운동을 실시하고 신체기능 및 장애물 보행의 변화를 측정하였다. 뇌졸중환자 20명을 대상으로 신체기능은 근력, 균형능력을 측정하였고, 장애물 보행은 장애물 극복속도와 최대수직여유를 측정하여 운동 전과 운동 후, 각 운동군 간을 비교분석하였다. 근력은 30초 의자에서 앉았다 일어나기, 균형은 FRT와 TUG 검사, 그리고 장애물 보행은 장애물 극복속도와 최대수직여유로 측정하였다. 실험결과 운동 후 ?고운동군은 요부안정화운동군에 비해 FRT와 장애물 극복속도는 유의하게 증가되었으며, TUG는 유의하게 감소되었다. 결론적으로 오타고 운동이 뇌졸중 환자의 신체기능 및 장애물 보행에 긍정적인 영향을 미친다.

• Journal of International Academy of Physical Therapy Research
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• v.9 no.1
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• pp.1387-1392
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• 2018

The purpose of this study was to investigate the effect of fall injuries on the balancing abilities and ankle flexibility. Fifteen of the voluntary participants had no experience of falling in the last two years (none falling group, NFG) and 15 others experienced at least one (falling group, FG). Static balance (sway length, sway area), dynamic balance (timed up and go (TUG), and functional to reach test (FRT) were measured in each group. In comparison of static balance, sway length was not significantly different between NFG and FG in both eyes open and eyes close, however the sway area of the FG was significantly wider than that of the NFG (p<.05). In dynamic balance comparisons, TUG of FG was significantly longer than that of NFG (p <.05), however FRT and STS were no significant difference between groups. Ankle flexibility was significantly higher in NFG than in FG. This study suggests that the fall prevention program should include methods for improving ankle stability and lower extremity function.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.10a
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• pp.381-386
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• 2002

Recently, The machine tools have been needed for high speed and accuracy to increase productivity. The most important thing to get a more stabilized machine is to know the frequncy response which has an effect on manufacture a lot. This problem should be considered seriously by many researchers. There are many programs about FEM. but just using FEM program to get information of the object is not enough to put our confidence in the stability of the structure design. Therefore, the purpose of this research is to make a study for proving one of the ways to design to produce stabilized a machine more efficiently by comparing FRT with Simulation through FEM. At this two tests, we can learn about the frequency response area causing resonance and we can reconfirm the result to trust.