• Proceedings of the KIPE Conference
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• 2008.06a
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• pp.631-633
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• 2008

현재 풍력발전 기술은 전 세계에서 가장 빠르게 성장하고 있는 기술로서 2010년도에 세계 보급량은 200GW를 넘을 것으로 추정되고 있다. 이에 우리나라도 풍력발전 기술 집약에 전력하고 있지만 풍력단지에 대한 운영 경험은 매우 제한적이며, 연계 기준 수립에 대한 기초가 부족한 실정이다. 따라서 한국계통의 특성을 고려한 연계 기준 및 최적 운영 방안 수립을 위한 다양한 국가에서 적용하고 있는 풍력 발전 단지에 대한 연계 및 운영 기준에 대한 검토가 필요한 실정이며 세계 각국에서 적용되고 있는 풍력 발전기의 계통 연계 기준을 분석 및 검토하였다.

• Journal of Power Electronics
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• v.9 no.3
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• pp.438-446
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• 2009

The performance of direct torque controlled (DTC) interior permanent magnet (IPM) machines is poor at low speeds due to a few reasons, namely limited accuracy of stator voltage acquisition and the presence of offset and drift components in the acquired signals. Due to factors such as forward voltage drop across switching devices in the three phase inverter and dead-time of the devices, the voltage across the machine terminals differ from the reference voltage vector used to estimate stator flux and electromagnetic torque. This can lead to instability of the IPM drive during low speed operation. Compensation schemes for forward voltage drops and dead-time are proposed and implemented in real-time control, resulting in improved performance of the space vector modulated DTC IPM drive, especially at low speeds. No additional hardware is required for these compensators.

• Proceedings of the KIPE Conference
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• 2008.06a
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• pp.139-141
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• 2008

This paper presents a PID controller and PI-PI dual loop controller for a single-phase inverter. The control parameters of conventional controllers are very difficult to make. But parameters of controllers based on pole-assignment are easy to make. Simulation results are presented for the system under R-L load, no load and change reference voltage.

• Proceedings of the KIEE Conference
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• 1988.11a
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• pp.53-55
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• 1988

The application of Sliding Mode Control for inproving the dynamic response of a Multi-Phase-Bipolar (MPB) Brushless DC motor based position Brushless DC motor system is presented. Sliding Mode Control gives fast dynamic response with no overshoot and zero steady state error. It has the important feature of bins highly robust. A design procedure is outlined for the Sliding Mode Controller for a MPB Brushless DC motor. Digital computer simulation of the overall position control system is carried out using a time domain model in the d-q reference frame.

• Proceedings of the KIEE Conference
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• 1998.11c
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• pp.907-909
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• 1998

This paper describes the effect of impulse current on degradation of ZnO blocks. In this study, an impulse current generator which can produce 8/20 [${\mu}s$], 3 [kA] and 4/10 [${\mu}s$], 5 [kA] waveform is designed and fabricated to simulate the lightning impulse current. The residual voltage, reference voltage, and leakage current flowing to the ZnO blocks are observed. The experimental results show that the leakage current increases continuously with the number of applied impulse current, but no significant changes in residual voltage and in operating voltage are observed until the ZnO block is destroyed. Also, it is confirmed that the main factor on degradation of ZnO blocks is rather the total energy applied to ZnO blocks than the peak value of the impulse current.

• Journal of Veterinary Clinics
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• v.33 no.4
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• pp.205-209
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• 2016

A 6-year-old male domestic shorthair cat was referred to Gyeongsang National University Animal Medical Center for labored breathing. According to the patient's history, the client had fed him commercial dog foods. The patient's hematological, radiographic, and echocardiographic examinations were evaluated for diagnosis. Echocardiography results showed marked dilations of ventricles and atriums and mitral regurgitation. A systolic dysfunction was detected. Plasma taurine concentration was lower than the reference range. Based on these results, the patient was diagnosed with feline dilated cardiomyopathy associated with taurine deficiency. Treatment included feline commercial foods, taurine, digoxin, furosemide, and clopidogrel. Digoxin was changed to pimobendan when normal blood pressure was achieved. Clinical signs improved gradually and no abnormalities were detected on echocardiograms at 10 weeks following onset of treatment.

• Journal of Veterinary Clinics
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• v.35 no.2
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• pp.67-69
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• 2018

Three dogs were referred for emergency care after fall accidents. All cases showed hyperglycemia at initial testing, with no history of diabetes mellitus. After varying periods of time, the blood glucose levels in all cases returned to within the reference range. The present report describes three cases of typical trauma-associated hyperglycemia in dogs.

• International Journal of Control, Automation, and Systems
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• v.3 no.spc2
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• pp.302-307
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• 2005

A novel neuro controller based simple neuro-structure with modified error function is introduced in this paper. This controller consists of two independent controllers, known as the voltage regulator and the angular controller. The voltage regulator is used to modify terminal voltage for the purpose of tracking a reference voltage. The angular controller is utilized to guarantee the stability of the system. In this structure each neuron uses a linear hard limit activation function that depends on the controlled variable and its derivatives. There is no need for parameter identification or any off-line training data. Two proposed controllers are merged by a smooth switch to build a complete controller. The effectiveness of the proposed novel control action is demonstrated through some computer simulations on a Single-Machine Infinite-Bus (SMIB) power system.

• Journal of Haehwa Medicine
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• v.22 no.1
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• pp.37-48
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• 2013

This study aims to summarize and makes a reference of anti-inflammatory activities of herbal medicines. In this process, this review collated papers of anti-inflammation-focused studies using herbal medicines in Oriental medical journals since 2003. Finally 221 papers were included and the type of materials, the type and effective classification of herbal medicines, the type of cells used in the experiments and the action and mechanisms of herbal medicine were analysed. The herbal medicines having the effects of decreasing fire and tonifying and nourishment were used the most. Most herbal medicines in this study can decrease proinflammatory cytokines, NO and prostaglandin 2 (PGE 2) production, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression by regulating of nuclear factor kappa B (NF-${\kappa}B$) and/or mitogen activated protein kinases (MAPKs).

• Journal of Ocean Engineering and Technology
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• v.13 no.3B
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• pp.91-98
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• 1999

In order to reject the steady-state tracking error, it is common to introduce integral compensators in servosystems for constant reference signals. However, if the mathematical model of the plant is exact and no disturbance input exists, the integral compensation is not necessary. From this point of view, a two-degree-of-freedom(2DOF) servosystem has been proposed, in which the integral compensation is effective only when there is a modeling error or a disturbance input. The present paper considers a synthesis problems of this 32DOF servosystem with direct transfer term in the system representation. And, a method how we may obtain a gain such that desirable transient response is achieved, is proposed in the presence of the modelling error and disturbance input.