• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.570-571
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• 2008

This paper presents a method for the determination of total transfer capability in interconnected power systems, which is based on sequential quadratic programming (SQP). The objective function is the maximization of the interconnected line flow. To calculate TTC the control variables are the active power of the generating units, the voltage magnitude of the generator, transformer tap settings and SVC setting. The state variables are the bus voltage magnitude, the reactive power of the generating unit, line flows and the tie line flow. The method proposed is applied to the modified IEEE 14 buses model system.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.31 no.10
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• pp.109-115
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• 1982

Reactor dynamics were studied by reactor noise at TRIGA MARK Il reactor whose rated power is 250KW thermal. The power spectral densities(PSD) of the noise were measured by stochastic method with high resolution digital filters and Fast Fourier Transformers. The transfer function of the reactor at zero power was identical to the theoretical characteristics. When the power was increasec above 1KW, reactor showed its poswer resonances at 3Hz and 10 Hz. It was analyzed that 3Hz peak was generated by heat transfer and coolant flow effects and 10Hz peak by nuclear reaction effects.

• Journal of Ocean Engineering and Technology
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• v.33 no.3
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• pp.229-235
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• 2019

In this study, a two-dimensional oscillating foil with forward speed in a propagating wave flow field was considered. The time-mean power to maintain the heaving and pitching motions of the foil was analyzed using the perturbation theory in an ideal fluid. The power, which was a non-linear quantity of the second-order, was expressed in terms of the quadratic transfer functions related to the mutual product of the heaving and pitching motions and incoming vertical flow. The effects of the pivot point and phase difference among the disturbances were studied. The negative power, which indicates energy extraction from the fluid, is shown as an example calculation.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.3
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• pp.1450-1463
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• 2019

The problem towards crowd behavior recognition in a serious clustered scene is extremely challenged on account of variable scales with non-uniformity. This paper aims to propose a crowed behavior classification framework based on a transferring hybrid network blending 3D res-net with inception-v3. First, the 3D res-inception network is presented so as to learn the augmented visual feature of UCF 101. Then the target dataset is applied to fine-tune the network parameters in an attempt to classify the behavior of densely crowded scenes. Finally, a transferred entropy function is used to calculate the probability of multiple labels in accordance with these features. Experimental results show that the proposed method could greatly improve the accuracy of crowd behavior recognition and enhance the accuracy of multiple label classification.

• Proceedings of the KIPE Conference
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• 2014.07a
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• pp.321-322
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• 2014

In this paper, a zero-voltage switching (ZVS) phase shift full-bridge converter is analyzed. The small-signal model is derived to design a digital controller. PLECS simulation shows how sampling method effects on transfer function of ZVS phase shift full-bridge converter.

• Proceedings of the KIPE Conference
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• 2012.07a
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• pp.423-424
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• 2012

본 논문에서는 피크 전류 모드 제어를 적용한 플라이백 컨버터의 정확한 Control-to-Output Transfer Function을 제시한다. 기존 저주파 극점만으로 간략화 된 모델은 실제 디스크리트 모델(Discrete Model)과 소신호 해석에서 많은 차이를 보인다. 본 논문에서는 정확한 저주파 극점을 유도하고, PSIM을 통한 모의실험을 통해 제안된 모델에 대한 정확성을 검증한다.

• Journal of Power System Engineering
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• v.18 no.5
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• pp.22-27
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• 2014

The objectives of this paper are to obtain an empirical equations regarding the correlations between heat transfer and pressure drop of oval fin-tube heat exchanger having large diameter using wilson plot method. It was difficult to find any recommendable heat transfer and friction factor correlation available for our large diameter experimental cases. Overall heat transfer coefficients are composed of the heat transfer coefficients both inside and outside tubes. The resulting empirical correlations for the Nui and f-factor are given as $Nu_i=0.0146Re^{0.809}Pr^{0.3}$ and $f=4.366Re^{-0.64}$, respectively. The empirical correlations of the Nui and f-factors were developed for the large diameter oval finned-tube heat exchanger as a function of the Reynolds number. As the EG(Ethylene glycol) and air flow rate increases, the heat transfer rate and pressure drop is increased largely.

• Journal of the Korean Solar Energy Society
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• v.27 no.3
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• pp.63-69
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• 2007

The heat transfer characteristics of inorganic salt for high temperature heat storage material of solar power system were examined. The inorganic salts employed in this study was a mixture of $NaNO_3$ and $KNO_3$ and the operating temperature range was determined by measuring the melting temperature with DSC and by measuring the thermal decomposition temperature with TGA. The heat transfer characteristics was qualitatively obtained in terms of temperature profiles of salt in the tanks during the heat storage and heat release process as a function of steam flow rates, steam inlet temperature and the inlet position of steam. The effects of steam flow rates and inlet temperature of steam were experimentally determined and the effect of natural convection was observed due to significant density difference with temperature.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.52 no.11
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• pp.647-654
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• 2003

As electrical power system has become complicated and enlarged to cope with the increasing electric demand, it has to be expected that higher speed, higher reliability, higher function and higher arithmetic ability in protective relay should be realized. Therefore, in this papers, by hardware design and implementation used DMA controller that transfer blocks of data to any location in the memory map without interfering with CPU operation, CPU utilization is increased effectively, as a result it made possible to implement multi-function digital protective relay which has high trust and high function of protection as well as control and metering for power transformers using single processor(DSP).

• Archives of Reconstructive Microsurgery
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• v.11 no.1
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• pp.41-46
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• 2002

Purpose : To assess the clinical results of second toe-to-finger transfer in traumatic amputated index finger. Materials and Methods : For the clinical evaluation, we have analyzed 12 patients with ROM of finger joints, pinch power, static two point discrimination, life functional assessment, and patient's satisfaction. Results : In genral ROM was $54.4^{\circ}$ at MP joint, $17^{\circ}$ at PIP joint and $6.7^{\circ}$ at DIP joint. Pinch power was good in 3 cases, fair in 7 cases, and poor in 2 cases. Daily life activity and patient's acceptance were satisfactory. Conclusion : Although transfered toe function may be poorer than normal finger, the hand was restored to a useful, sensate and versatile functional unit.