• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 A
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• pp.325-329
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• 1994

This paper describes a compact design and control method of PWM inverter-mounted induction motor especially designed for reducing the size and weight considerably, which may be applied to the speed control system such as air conditionr,conveyor and textile mill, etc. To obtain higher power density without derating performance, a new mechanical configuration unifying the inverter circuit and motor is proposed. Also, through the use of current minimization control method during V/f operation it is possible to reduce the size of heat-sink related to the losses of power circuit. By the proposed design method, a compact inverter-mounted induction motor system of 1Hp is built and its validity can be verified through the experimental results.

• 한국동물위생학회지
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• 제17권1호
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• pp.54-60
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• 1994

Anaplasmosis is a tick-borne disease mainly of cattle, sheep, and goats. Anaplasmosis in goat had been reported at last year by authors. The disease brought the economic losses in the goat farm in Chonbuk province. In order to treat the disease, a long-acting formulation terramycin injectable solution was used experimental animals which indigenous goats were sick with moderate anemia. We were devided into two groups was treated with single dosage (20mg /kg of body weight). one group was treated with single injection, the other group was treated with twice of the same dosage intramusculary injection. The results indicate that the use of long-acting terramycin would minimize clinical signs of anaplasmosis infection in goat. After treament the differrences of hematological appearences and parasitaemia were observed in the effect of terramycin treatment. obviously, increased value of RBC. HB and HCT, and parasitaemia by means of Giemsa staining and acrydine orange staining was observed decreased due to treatment.

• 대한수의학회지
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• 제1권1호
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• pp.65-70
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• 1961

Many losses in domestic animals have bern reported in this country, since sodium monofluoroacetate (Compound 1080) was used as a rodenticide. Lesions described inclubed multiple petechiae in epi- and endocardium, lung and intestinal mucosa, or superficial necrosis of the gastric mucosa. In this studies as to the poisoning 7 rabbits were administered 0.6mg (Group I), 0.4mg (Group II), and 0.3mg (Group III) of sodium monofluoroacetate per kilogram of body weight. and the results obtained were as follows: In addition to the changes mentioned above fatty degeneration in central parts of hepatic lobule or nut meg liver, haemorrhagic feci in cerebral cortex and leptomeninges and fatty degeneration in kidney and cardiac muscles were found.

• 전력전자학회논문지
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• 제18권5호
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• pp.443-447
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• 2013

This paper deals with LLC resonant converter of on-board charger for electric vehicle charging. Generally, the on-board charger must have a very widely charging voltage, higher efficiency, higher power factor, lower volume and lower weight. For reducing the switching losses, voltage and current stress of the device, the on-board charger is apply the half-bridge LLC resonant converter topology. To have a wide voltage range, it is design the hardware parameters and determine the switching frequency range of the LLC resonant converter. The experimental results show a wide charge voltage.

• 조명전기설비학회논문지
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• 제12권4호
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• pp.90-99
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• 1998

DC/DC 컨버터의 리액티브 성분의 물리적 크기를 저감하고 동특성을 개선하기 위해서는 동작 스위칭 주파수 를 증가시키는 것이 바람직하다. 그러나 이것은 발열 및 스트레스로 인한 파워 소자의 파괴, 스위칭 손실 증가 로 인한 효율 감소 및 EM! 동의 문제가 발생한다. 따라서, 본 논문에서는 이러한 문제점을 해결하기 위해 보조 회로를 웅용한 소프트 스위칭 Forward-Flyback PWM DC/DC 컨버터를 제안하였다. 시뮬레이션 및 실험 결과로부터 제안한 컨버터의 타당성을 확인하였다.

• 한국표면공학회지
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• 제23권2호
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• pp.11-17
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• 1990

The erosion characteristice of plasma-sprayed tungsten carbide chromium carbide coatings were investigated. Erosion tests were perfomed at room temperature by using Al2O3 and SiC particles accleerated in air stream. Weight losses of the coatings were measured over a range of paricle velocities and impingement angle. It was found that, for both of this coatings, the maximum erosion occurrd at a normal angle of impact, and the erosion rate at this impact angle was a power function of pparticle velocity. The values of the velocty emponent were between 3.07 and 3.50 Erosion value of chromium carbide coating was higher than that of tungsten carbide coating.

• Food Science and Biotechnology
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• 제15권3호
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• pp.441-446
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• 2006

The biological effects of heating and chemical treatment on castor meal were investigated in order to develop a procedure to inactivate its antigenic activity in a way that is suitable for industrial applications. A 1% solution of purified castor bean allergen (CB-1A) was heat-treated with or without exposure to NaOH and NaOCI (250 ppm each). CB-1A exhibited extreme stability when heat-treated alone. In the presence of NaOH and NaOCl, CB-1A showed a drastic decrease in antigenic activity as the temperature surpassed the critical level of $70^{\circ}C$. The gradual disappearance of disc gel electrophoresis bands presumably responsible for the allergenicity of CB-1A, along with the significant losses of the amino acids phenylalanine, methionine, arginine, histidine, and cysteine correlated with the loss of CB-1A activity. CB-1A showed a single symmetrical band in SDS acrylamide gel electrophoresis with an estimated molecular weight of 6,000 daltons. The chemical and heat treatments reduced the disulfide bond content of CB-1A by 9.1% with a coincident increase in sulfhydryl bonds.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집 특별세미나,특별/일반세션
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• pp.623-628
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• 2009

There is an increasing demand for efficient high power/weight auxiliary power supplies for use on high speed traction application. Many new conversion techniques have been proposed to reduce the voltage and current stress of switching components, and the switching losses in the traditional pulse width modulation(PWM) converter. Especially, the phase shift full bridge zero voltage switching PWM techniques are thought most desirable for many applications because this topology permits all switching devices to operate under zero voltage switching(ZVS) by using circuit parasitic components such as leakage inductance of high frequency transformer and power device junction capacitance. The proposed topology is found to have higher efficiency than conventional soft-switching converter. Also it is easily applicable to phase shift full bridge converter by applying an energy recovery snubber consisted of fast recovery diodes and capacitors.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.321-324
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• 2008

Recently, there is an increasing demand for efficient high power/weight auxiliary power supplies for use on high speed traction application. many new conversion techniques have been proposed to reduce the voltage and current stress of switching components, and the switching losses in the traditional pulse width modulation(PWM) converter. Among them, the phase shift full bridge zero voltage switching PWM techniques are thought most desirable for many applications because this topology permits all switching devices to operate under zero voltage switching(ZVS) by using circuit parasitic components such as leakage inductance of high frequency transformer and power device junction capacitance. The proposed topology is found to have higher efficiency than conventional soft-switching converter. Also it is easily applicable to phase shift full bridge converter by applying an energy recovery snubber consisted of fast recovery diodes and capacitors.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2009년도 추계학술대회
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• pp.333-336
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• 2009

장비의 리액터브 성분의 물리적 크기를 저감하고 동특성을 개선하기 위하여 동작스위칭 주파수를 증가 시키는 것이 우수하나 이러한 방식은 발열과 스트레스로 인한 전력소자의 파괴, 스위칭손실 증가로 인한 효율 감소등 다양한 문제가 발생하게 된다. 따라서, 본 논문에서는 이러한 문제점을 해결하기 위해 보조장치를 응용한 기동전류 회로를 적용한 하프브리지 방식의 Intense Pulse Light를 제안 하였다. 시뮬레이션 및 실험결과를 통해 20% 향상을 가져와 환자에게 보다 더 질적인 측정을 할 수가 있다고 확인하였다.