• 전력전자학회:학술대회논문집
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• 전력전자학회 2012년도 전력전자학술대회 논문집
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• pp.138-139
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• 2012

본 논문에서는 고주파 공진형 인버터 접속의 가열 코일로부터 비접촉 상태로 전자유도 와전류를 구조물에 가하여 발열하는 공진형 인버터를 이용한 유도가열 방식의 최적설계를 제안하였다. 설계한 시스템 인버터는 스위칭주파수 20[kHz] 대역에서 동작하는 하프-브리지 고주파 직렬 부하 공진형이며 LC공진 설계 시 부하 자체를 L로 설정하여 효율을 최대화 하였다. 또한 유도가열용 인버터에 적용 가능한 스너버회로의 특성분석을 통해 본 시스템의 최적화에 관한 연구를 하였다.

• 한국미생물·생명공학회지
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• 제17권4호
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• pp.273-276
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• 1989

Bti 균주를 배양하여 포자와 $\delta$-endotoxin의 복합물을 직접 field에 적용시키면 미생물 생태계에 변화를 초래할 가능성이 있으며, 배양 후 포자로부터 $\delta$-endotoxin만을 분리할 경우에는 대량생산을 위한 기술적인 어려움이 있다. 또한 $\delta$-endotoxin은 용혈성 단백질을 함유하고 있어 Bti 균주로부터 무포자이며 $\delta$-endotoxin을 생산하는 변이주의 분리와 아울러 $\delta$-endotoxin의 용혈성 인자의 제거 또는 약화를 시도하였다. 그 결과 Bti 균주를 열처리시켜 SPO3 (Spo$^-$ Cry$^+$) 변이주를 분리 선별하고, 그 $\delta$-endotoxin의 모기유충에 대한 LC$_{50}$ 및 응혈성을 조사해 본 결과 LC$_{50}$는 약 20배, 용혈성은 약 25배정도 야생주의 $\delta$-endotoxin에 비해 약화되었다. 이는 변이주의 $\delta$-endotoxin내에 28KDa 단백질의 소실에 기인된 것이라 생각되며, 이는 면역확산반응과 면역전기영동 및 SDS-PAGE에 의해 확인되었다.

• 대한수의학회지
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• 제43권3호
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• pp.429-433
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• 2003

This study was aimed to develop a more rapid, simple and sensitive method to determine ceftiofur in bovine serum using LC/MS with electrospray interface. Separation was achieved on the Nova-Pak $C_{18}$ reverse phase column. The mobile phase consisted of 0.1% acetic add in water (A) and acetonitrile (B) and gradiently flowed at the rate of 0.4 mL/min. As a result of analysis of blank muscle samples, matrix interference was not shown. Limit of detection and limit of quantitaion was 5 ng/g and 20 ng/g, respectively. The values of precision and recovery satisfied the guideline of NVRQS. The precision and recovery developed in this method are suitable and sensitive to determine the concentration of ceftiofur in the bovine serum. These results could be applied for the confirmation and quantification in the biofluid.

• 한국수산과학회지
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• 제37권5호
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• pp.380-384
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• 2004

The toxic impact of parathion on bagrid catfish (Pseudobagrus fulvidraco) juvenile was examined 96 hr $LC_{50}$ value of parathion estimated as 1 90 mg/L. Chronically, bagrid catfish were exposed for 30 days to concentrations of parathion, i.e. 63, 95, 190 and $380\;{\mu}g/L$, representing 3.3, 5.0, 10.0 and $20.0{\%}$ of the 96 hr $LC_{50}$. Survival rate was significantly affected by the concentration over $63\;{\mu}g/L$ after 10 days. Growth rate, specific growth rate (SGR) and feed efficiency were reduced in time as concentration dependent manner. Growth rates of the exposed groups were significantly reduced as $28.06-60.63{\%}$ to the control fish, SGR was decresed as $1.50-4.72{\%}$ and feed efficiency was declined as $6.10-11.90{\%}$. It can be concluded that if p. lulvidraco is chronically exposed to parathion over $63\;{\mu}g/L$ concentration, the physiological damages might affect growth factors of the fish.

• 한국실내디자인학회논문집
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• 제14권5호
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• pp.218-225
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• 2005

In this apartment market, many apartments are being reconstructed within even less than 20 years from their first construction. This entails many problems in environmental and economical facets, for which many researches are under way in several institutions and universities. International cases show that the international trend goes for remodeling of maintenance, management, and repairing rather than new building. The purpose of this study is to investigate the factors of cost evaluation for establishing the time period of apartment based on durability of material and equipment while considering the economic feasibility of apartment, when remodeling as a concept of sustainability regarding building is being vitalized. This study investigates the proper period of remodeling in consideration of weight accruing to the LC(Life Cycle) and cost based on the standardized durability. The weight of cost, period establishment analysis, and LC according durability varies the data values of remodeling periods. The physical durability and cost from this data enable the investigation into not only the repair period of individual materials of the apartment but also remodeling period.

• 한국수산과학회지
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• 제42권6호
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• pp.628-632
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• 2009

In order to estimate acute toxicity of various heavy metals on mysid, Neomysis japonica, the experiments were conducted by renewal bioassay method at $20\pm0.5^{\circ}C$ and $30\pm0.3$ psu salinity. The 96 hr $LC_{50}$ of Neomysis japonica exposed to cadmium, copper, zinc, arsenic, lead and chromium were $90.4\;{\mu}g/L$, $82.3\;{\mu}g/L$, $646.1\;{\mu}g/L$, $1488.5\;{\mu}g/L$, $1758.8\;{\mu}g/L$ and $1609.6\;{\mu}g/L$, respectively, and were ranked in order of toxicity: copper > cadmium > zinc > arsenic > chromium > lead.

• 조명전기설비학회논문지
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• 제21권8호
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• pp.20-26
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• 2007

본 논문은 반도체 소자의 사용없이 구성된 LC 공진 타입의 점화기를 분석하고 설계하였다. 일반적으로 사용되고 있는 점화기는 다이악, 아크갭, SCR과 같은 반도체 소자가 사용된다. 이러한 반도체 소자의 사용으로 인해 회로의 구성이 복잡해지며 신뢰성이 저하된다. 따라서 본 논문에서는 수동 소자로만 구성된 점화기 회로를 분석 및 설계하였으며 제안한 점화기는 램프의 정상 상태에서는 영향을 미치지 않는다. 수학적 분석, 컴퓨터 시뮬레이션과 1[kW] 메탈 핼라이드 램프용 전자식 안정기를 제작하여 실제 적용해 봄으로서 제안한 점화기의 유용함을 증명하였다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.68-71
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• 2003

To be able to show moving images without visual problems like blurring and tailing, the response time of liquid crystal display (LCDs) must be improved. In this paper we will discuss our progress in improving the response time by optimizing the cell configuration and the use of new liquid crystal mixtures. A 20.1inch diagonal UXGA IPS TFT-LCD has been developed having a response time as fast as l-frame time (16msec) for white-black operation and less than 16msec in all gray levels without applying ODC (Over Driving Circuit). This is very important because one of the technology to reduce motion blurring, the use of scanning backlight is conditioned by 16msec for all grays. The excellent gray-to-gray response can be explained by virtue of fundamental characteristics of S-IPS mode and makes a good contrast with the results of VA mode.

• JSTS:Journal of Semiconductor Technology and Science
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• 제8권4호
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• pp.295-301
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• 2008

Recently, the demand on mm-wave (millimeter-wave) applications has increased dramatically. While circuits operating in the mm-wave frequency band have been traditionally implemented in III-V or SiGe technologies, recent advances in Si MOSFET operation speed enabled mm-wave circuits realized in a Si CMOS technology. In this work, a 58 GHz CMOS LC cross-coupled VCO (Voltage Controlled Oscillator) was fabricated in a $0.13-{\mu}m$ Si RF CMOS technology. In the course of the circuit design, active device models were modified for improved accuracy in the mm-wave range and EM (electromagnetic) simulation was heavily employed for passive device performance predicttion and interconnection parasitic extraction. The measured operating frequency ranged from 56.5 to 58.5 GHz with a tuning voltage swept from 0 to 2.3 V. The minimum phase noise of -96 dBc/Hz at 5 MHz offset was achieved. The output power varied around -20 dBm over the measured tuning range. The circuit drew current (including buffer current) of 10 mA from 1.5 V supply voltage. The FOM (Figure-Of-Merit) was estimated to be -165.5 dBc/Hz.

• 전자공학회논문지SC
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• 제45권3호
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• pp.80-85
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• 2008

기존의 캡슐형 내시경은 공간적 제약으로 인해 약 30mW 용량의 1차 전지를 사용한다. 그러나 1차 전지를 사용하는 방식은 배터리 용량의 한계와 1회용 소모품으로 가격이 비싸다. 이러한 문제를 해결하기 위해 신체 외부에서 캡슐형 내시경에 무선으로 에너지를 전송 방식을 제안하였다. 제안된 방식은 송 수신측 양단에 LC공진 회로를 이용하여 $10{\sim}20cm$의 공극을 통해 송신측 코일에서 캡슐형 내시경으로 에너지를 전달하는 방식이다. 위치와 방향성에 상관없이 에너지 효율의 증가를 위해 수신측 코일은 페라이트 코어를 이용한 3축 권선 방식을 이용하였다. 실험에 의한 측정 결과 제안된 방식은 수신측 회로에 안정적으로 30mW의 전력을 공급할 수 있음을 확인하였다.