• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.9 no.4
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• pp.78-85
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• 1995

This paper covers stability and stabilization of Multi-Excited Induction Motor used in numberous electric equipment system of industrial field. The induction motor with multi-excitation has tow sets of three-phase system : One is connected to the AC source to supply most power required at the load, and the other is to the inverter for variable frequency and/or magnitude of voltage. The conventional induction motor is operated under single excitation mode only, that is called induction mode. But in multi-excited induction motor both the induction mode and the synchronous mode are possible, and the proposed multi-excited induction motor can be driven as a synchronous motor by the extra three-phase input. At the synchronous mode the efficiency is improved so higher than that at induction mode or conventional induction motor. The rating of the inverter used for speed control of numberous electric equipment system can be reduced upto one-tenth of that for conventional induction motor. Also the cost and maintenance fee of multi-excited induction motor can be reduced compared to any other motor.

• ETRI Journal
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• v.32 no.1
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• pp.53-61
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• 2010

We propose a simple technique to stabilize the optical output intensity of a fiber ring resonator. The electronic feedback circuit system, which consists of two voltage control oscillators, a phase comparator, and a low pass filter, is applied to the fiber ring resonator in order to compensate the optical phase shift in the ring loop. The reference electrical signal determines the operating condition of the fiber ring resonator for the desired optical output signal. The experimental results within the operating range agree well with the analytical results. The simulated performance of the proposed model is also compared with that of other existing models and shows significant improvement over them.

• Journal of the Korean Ceramic Society
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• v.27 no.5
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• pp.613-618
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• 1990

The pure and 6mol% MgO-doped ZrO2 powders were prepared by hot petroleum drying method. The power characterization of homogeneous fine powder was indentified by the method of thermal analysis, BET and electron microscope. The transformation, content of t-ZrO2, crystallite size and apparent strain were measured by X-ray diffraction technique. The prepared powders were transformed in order of amorphouslongrightarrowmetastable cubic ZrO2longrightarrowmetastable tetragonal ZrO2longrightarrowstable monoclinic ZrO2 by a adequate heat treatment. The stabilization of metastable phase can be discussed in terms of energetial concept ; the difference of surface energy and internal strain in particle.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.418-423
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• 1992

In this paper, a model reference adaptive control algorithm is applied to the design of the normal acceleration controller for missiles with nonminimum-phase characteristics. The method used in this paper is due to Ohkubo. In this scheme, a feedforward compensator is designed first so that the extended system becomes minimum-phase and after that an adaptive control algorithms is designed for the extended system. The feedforwrd compensator is obtained by solving the robust stabilization problem. It is shown that the performance of the designed controller is satisfied via computer simulation.

• Proceedings of the Optical Society of Korea Conference
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• 2005.02a
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• pp.214-215
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• 2005

• Proceedings of the Optical Society of Korea Conference
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• 2007.07a
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• pp.87-88
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• 2007

• Proceedings of the Optical Society of Korea Conference
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• 2006.02a
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• pp.141-142
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• 2006

• Korean Journal of Applied Biomechanics
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• v.22 no.1
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• pp.83-94
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• 2012

The purpose of this study was to analyse the effect of posture correction & stabilization according to horse rider's(n=10) skill levels of novice(0wk), mid-skill(12wk) & skill(24wk) in walk & trot. First, Mean posture of 3 times experiments; Anterior & posterior leaning posture of trunk showed rather unstable according to progress of the stages of TD1, TO, TD2 phase, and also shoulder & elbow angle, which effects to the distance from bit to rein, showed unstable riding posture. There was close relationship between shoulder and elbow Angle in walk and hip, knee & ankle angle in trot. Second, Posture correction & stabilization according to riding skill levels; Anterior & posterior leaning posture of trunk did not show significant difference statistically but showed approaching tendency to trunk's vertical line and showed significant difference(p<.05) according to improvement of skill levels in walk & trot horse riding. Hip angle showed significant difference according to progress of the stages of TD1, TO, TD2 phase(p<.05) and showed tendency maintaining the larger thigh flexion according to improvement of skill levels in walk & trot. Knee angle showed more stable posture by maintaining the larger flexion between thigh and shank according to improvement of skill levels in walk & trot(p<.05). Ankle angle also showed tendency maintaining the larger plantar flexion of foot according to improvement of skill levels in walk & trot. When considering the above, regular horse riding program could be useful in posture correction & stabilization according to improvement of skill levels of novice(0wk), mid-skill(12wk) & skill(24wk) in walk & trot.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.268-274
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• 2011

In railway, Ballast plays an essential role as intermedium in transmitting train load to subgrade safely. Gyoung-Bu HSL 1st phase consists of ballasted track except for over 5km long tunnels. Ballast track occurred track irregularity by train loads and requires periodic maintenance work. However, Repetitive train operation and tamping work cause to accelerate track irregularity and ballast deterioration such as abrasion and crushing. For these reason, Track irregularity areas had occurred ballast cleaning work to improve track quality. However, for the train to run safety, ballast cleaner working area needs train speed reduction and track stabilization work due to ballast relaxation and initial settlement. In this study, according to train speed-up and cumulative traffic tonnage, we measured and analyzed the track settlement and acceleration of sleepers to evaluate of track stabilization in order to keep the ballast condition stable after cleaning work.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.49-52
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• 2001

An experimental study was conducted to test the feasibility of degradative solidification/stabilization (DS/S) process in treating tetrachloroethylene (PCE) in solid phase systems. The Fe(II)-based ds/s process successfully treated PCE in a soil at the reaction rates that would not allow significant release of the contaminant in the environment. A leach model was also developed that could describe the relative importance of leaching and degradation in ds/s. The first and second Damkohler numbers and dimensionless time were important parameters that determined leaching precesses in wastes treated by ds/s.