• 한국고분자학회지:고분자과학과기술
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• 제19권6호
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• pp.530-540
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• 2008

• 융합신호처리학회 학술대회논문집
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• 한국신호처리시스템학회 2000년도 하계종합학술대회논문집
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• pp.125-128
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• 2000

가상적인 검출잡음을 가정하고 칼만 필타(Kalman Filter)를 고려하여 근사적 최적 레귤레이터의 특성에 가깝게 함으로써 견실 안정성을 회복할 수 있는 제어 시스템의 설계에 관하여 검토한다. 본 연구에서는 관측기를 이용한 최적 레귤레이터 계에 적분기를 결합한 견실제어계의 설계법을 나타내고 견실성을 회복할 수 있는 제어기의 파라미터 설정법을 나타낸다. 제어대상의 파라미터 변동에 의해서 생기는 등가인 외란을 억제하고 과도특성이 변하지 않는 제어 시스템을 모델 매칭의 원리에 기초하여 설계한다.

• 대한물리치료과학회지
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• 제3권4호
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• pp.181-187
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• 1996

The purpose of this study is to help understand the pressure pain threshold's comparison following time progress after IMS to the trigger point and recognize this methode' effect for treating these kind of myofascial pain syndrome in clinic. Resently, myofascial pain syndrome is a disease that keeps the highest rate of patients visiting the Department of Rehabilitation Medicine. and so one should understand the change of IMS'effect following time progress for patients to be dealt rightly in clinic. In addition, the theory and treatment of myofascial pain syndrome needs to be understood or to be dealt rightly for therapists to treat and to approach to the right moment in right mode for the patients with myofascial pain syndrome. Therefore, one should know where to stimulate and why one stimulate trigger point and what effect one obtain after IMS.

• 조명전기설비학회논문지
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• 제14권6호
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• pp.12-17
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• 2000

IN induction heating system the high frequency operation allows a rapid response to current fluctuation in the inverter and result in improved welding quality. To work induction heating of nonferrous metals, a welding power supply is need high working frequency and high power. This paper is shown design technique for increasing working frequency in induction heating for welding coppers. A series-parallel resonate inverter consists of H-type bridges, each of whose arms is composed of a combination of two parallel IGBTs. Inverter operating with the fixed frequency is controlled by pulse width modulation (PWM). As switching adapted the Zero-Voltage Switching technique to reduce switching losses the system is high efficiency. The propose inverter has feature which is high efficiency for very wide load variations with a narrow range of duty cycle ratio control and load short circuit capability. Detailed experimental results obtained from a 48[V] output, 500[W] experimental inverter are presented to verify the concept.

• Journal of Advanced Marine Engineering and Technology
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• 제8권1호
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• pp.64-71
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• 1984

In this paper, the fundemental equation on the Trans-vector control of 3.phi. Induction motor drive and the new equivalent circuit to be adapted for this equation, have been obtained, and control drives system to be coincide with this equation is made. Therefore, it has been obtained that control scheme can always be used motor drive. 3.phi. Induction motor drive has been got the dynamic behavior the same as that of DC motor drive. The drive dynamic response is very rapid because of Trans-vector control on the I_1$ (primary current) and .${\omega}_1$ (frequency of primary current) of the Induation mechine. This paper indicates that a practicality of the drive control system and the rationalty of the theory have been identified with the experimental results. The effect of parameter variations on the drive dynamic response can be evaluated from these results.

• Journal of Advanced Marine Engineering and Technology
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• 제29권1호
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• pp.132-139
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• 2005

This paper describes the application of sliding mode control based on the variable structure control(VSC) concept for high-performance position control of an induction servo motor A design method based on external load parameters has been developed for the robust control of AC induction servo drive. Also, a slip frequency vector control with software current control technique has been adopted to achieve fast response of an induction motor drive The position control scheme is comprised of a variable structure controller and slip frequency vector control for inverter fed induction servo motor. Simulated results are given to verify the proposed design method by adoption of sliding mode and show robust control for a change of shaft inertia, viscous friction and torque disturbance.

• Journal of Advanced Marine Engineering and Technology
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• 제9권3호
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• pp.250-256
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• 1985

With the advant of thryistors having large peak inverse voltages, current-source inverters are becoming very popular to feed induction motors. But it is very difficult to analysis the commutation. Since the actual variation of current during commutation is neither instantaneous nor linear and is effected by many parameters. Minimized bias-time of reverse voltages during commutation is expressed in term of machine parameters, capacitor voltage, load current and so on. The minimized bias-time is computed with y and z and also the commuation mechanism is tested on 2.2 kw induction motor. The computed results are compared with the experimental results, and the results give a good information for designing the commutation mechanism.

• 한국가구학회지
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• 제10권1호
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• pp.23-32
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• 1999

The ultrastructural characteristics of shear fracture surfaces of laminated wood prepared from major four Korea wood specimens were examined. Commercial urea and urethan resin were used as adhesives for laminated woods of both homospecies and heterospecies. The morphology of fracture surface was observed using an optical microscopy and scanning electron microscopy. Three anatomical failure types were recognized : intercell failure, intrawall failure and transwall failure. In dry specimen, failure occurred mainly in woods. Laminated woods of softwoods showed mostly intrawall failure and transwall failure of tracheids, and them of hardwoods indicated mainly intrawall failure and interwall failure. Laminated woods prepared with urethan resin showed coarse fracture surface, on the other hand, those prepared with an urea formaldehyde resin had clean surface. In wet specimen, failure occurred dominantly in glue line. Intrawall failure and flags were characterized in laminated wood prepared with urethan resin. In heterospecies laminated woods, failure was occurred mainly in softwood. Consequently, fracture morphology of laminated wood may be influenced by adhesives, moisture content, species and anatomical characteristics.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1991년도 하계학술대회 논문집
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• pp.717-719
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• 1991

In this paper, the basic principle and theory of fuzzy control was discribed, and the control plant was estabilished to construct system. Computer software for fuzzy control was developed, and evaluation of the properties was performed by simulation. In this result, the speed of response(time constant + dead time) was investigated, and when the control plant has astable elements, the stabilization was discribed.

• 전기학회논문지P
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• 제66권4호
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• pp.219-223
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• 2017

In this paper, we calculated the losses in the high voltage lines of power distribution system. The losses caused by high voltage lines are calculated using maximum current, resistance, loss factor, and dispersion loss factor. The accurate extraction of these factors are very important to calculate the losses exactly. Thus, the maximum loads are subdivided to regions and calculated monthly for more accurate maximum current calculation. Also, the composite resistance is calculated according to the ratio of the used wire types. In order to calculate the loss factor, the load factors according to the characteristics of each region were calculated. Finally, the losses of the distribution system is calculated by adding the losses by the transformers and the low voltage lines.