• 조명전기설비학회논문지
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• 제26권8호
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• pp.1-7
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• 2012

In this paper, a new LED driving circuit which is able to control dimming of LED is proposed using charge pump. The proposed LED driving circuit steps down the input voltage to operate LED without DC-DC converter. The operation of this driving circuit is verified by P-Spice simulation, and the characteristics of the driving circuit is measured and evaluated in the experiments. As a result, the driving circuit efficiency of 88.5[%] is obtained when all LEDs are turned on by digital control method at the highest dimming level(255/255).

• 산업기술연구
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• 제31권B호
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• pp.67-73
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• 2011

Ceramic metal halide lamps have been widely used due to long lifetime, high luminous efficiency and good colour rendering. In this paper, we developed dimming control system of electronic ballast for 70W ceramic metal halide lamp by using 1-10V interface. The proposed electronic ballast is consists of EMI filter, Full-wave rectifier, Active PFC, DBI(Dual Buck Inverter), Igniter and control circuit.It enables to supply both low-frequency rectangular wave voltage and current to the lamp by using DBI(Dual Bcuk Inverter) structure. By using 1-10V interface, the system that able to dimming the lamp is demonstrated by P-spice simulation and experimental results.

• 대한전자공학회논문지
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• 제22권5호
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• pp.50-56
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• 1985

A common failure mechanism in bulk CMOS integrated circuits is the latch-up of parasitic SCR structure inherent in the bulk CMOS structure. Latch-up triggering and holding charac-teristics have been measured in the test devicrs which include conventional and Schottky-damped CMOS structures with various well depths and n+/p+ spacings. It is demonstrated that Schottky-clamped CMOS is more latch-up immune than conventional bulk CMOS. Finally, the simulation results by circuit simulation program (SPICE) are compared with measured results in order to verify the validity of the latch-up modal composed of nan, pnp transistors and two external resistors.

• 전자공학회논문지B
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• 제28B권11호
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• pp.859-865
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• 1991

The paper proposes a design of high-speed dynamic CMOS PLA (Programmable Logic Array) which performs stable circuit operation. The race problem which nay occur in a NOR-NOR implementation of PLA is free in the proposed dynamic CMOS PLA by delaying time between the clocks to the AND- and to the OR-planes. The delay element has the same structure as the product line of the longest delay in the AND p`ane. Therefore it is unnecessary to design the delay element or to calculate correct delay time. The correct delay generated by the delay element makes the dynamic CMOS PLA to perform correct and stable circuit operation. Theproposed dynamic CMOS PLA has few variation of switching delay with the increasing number of inputs or outputs in PLA. It is verified by SPICE circuit simulation that the proposed dynamic CMOS PLA has the better performance over existing dynamic CMOS PLA's.

• Plant Resources
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• 제8권2호
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• pp.96-102
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• 2005

As part of developing natural food preservatives, the antimicrobial effect of ethanol and water extracts from the Cruciferous vegetable was examined Korean traditional Brassica juncea Coss. was used widely as an ingredient of Kimchi, a natural flavoring and spice for a long time. Antimicrobial activities were examined against 15 microorganisms which were food-born pathogens and/or food poisioning microorganisms and food-related bacteria and yeasts. Ethanol extract from leaf mustard showed an antimicrobial effect in most of the strains used in the present study. The lowest minimum inhibitory concentration (MIC) were seen in Bacillus subtilis and Bacillus natto at 10 mg/ml. MIC of water extract was 40-60 mg/ml for bacteria and yeast. Antimicrobial activity of the ethanol extract was not disappeared by the heating at $121^{\circ}C$ for 15 min and not affected by pH.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -2
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• pp.1017-1020
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• 2000

In this paper, a CNN using 1-dimensional chaos circuits with controllable nonlinear functions is proposed. The proposed CNN consists of $\p{times}q$ chaos circuits which are called cell circuits. The nonlinear functions of the cell circuits can be controlled by employing fuzzy scheme. Thanks to the controllability of the nonlinear functions, the proposed circuit can adjust transition behavior of the CNN electronically. Furthermore, the chaotic behavior of the cell circuit which is a portion of the proposed CNN is simple since the cell circuit is a 1-dimensional chaos circuit. To confirm the validity of the circuit design, SPICE simulations were performed concerning the proposed CNN.

• 전력전자학회논문지
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• 제5권3호
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• pp.246-253
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• 2000

전동기의 제어기법과 제어기 등의 발달로 유도전동기는 산업용으로 널리 보급되고 있으며, 유도전동기를 고효율로 제어하기 위하여 PWM 인버터가 널리 사용되고 있다. 그리고 IGBT와 같은 고속 스위칭 소자의 발달로 인해 전압형 PWM 인버터의 스위칭 주파수가 증가가 가능하게 됐으며, 그로 인해 매우 우수한 동작 특성을 가지게 되었다. 그러나 고속 스위칭은 전압과 전류의 급격한 변화로 인해 매 스위칭마다 발생하는 고주파 성분의 커먼 모드전압과 전류를 발생하게 되고 이들은 베어링 전류와 축전압, 전도 및 방사 EMI, 기기의 절연수명 단축, 등의 악영향을 유발한다. 본 연구에서는 이러한 커먼 모드 전압과 전류에 대한 시스템 레벨 해석이 가능한 시뮬레이션 기법에 대해 실제 측정과 시뮬레이션을 통해 검정하였다. 이를 통해서 커먼 모드 전압과 전류가 PWM 인버터 시스템의 각 부에 미치는 영향을 쉽게 확인 할 수 있으며, 커먼 모드 전압과 전류의 저감을 위해 추가될 수 있는 부가적인 보조회로의 영향에 대해서도 제시된 시뮬레이션 기법을 통해 확인 할 수 있다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 B
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• pp.1098-1100
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• 1993

In this paper, We found the thermal characterstic of impulsed magnetizing fixture system through the SPICE modeling and investigated the applied possibility in application aspects. As the detailed thermal characteristic of magnetizing fixure can be obtained, the efficient design of the magnetizing fixture which produce desired magnet will be possible using our thermal modeling. The purpose of this work is to compute the temperature increasing for different magnetizing conditions. The method uses multi-lumped model with equivalent thermal resistance and thermal capacitance. The model ing and experimental results are in close agreement.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.1077-1078
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• 2007

본 논문은 고출력 MHL(Metal Halide Lamp) 전자식 안정기에 적합한 새로운 형태의 수동 PFC 회로를 제안하였다. 제안한 수동 PFC 회로는 저단가로 구현할 수 있으며 수동 소자의 사용으로 인해 신뢰성을 향상시켰다. 또한 기존의 수동 PFC 회로보다 입력 전류의 THD 및 역률을 개선하였다. 제안된 수동 PFC 회로에 사용된 소자값의 결정 방법을 수식적으로 제시하였으며 P-spice를 이용한 컴퓨터 시뮬레이션 및 1000W MHL 전자식 안정기에 실제 적용한 실험을 통하여 제안된 수동 PFC의 성능을 증명하였다.

• 생약학회지
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• 제50권3호
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• pp.159-164
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• 2019

Zanthoxylum Peel is widely used as a common spice for a variety of foods. In the orient, it has also been used as traditional agents for treating diseases such as indigestion. Recently, Zanthoxylum Peel has been reported to have anti-cancer activity, anti-microbial activity, and anti-inflammatory activity. Chemical components are known sanshool compounds and xanthoxylin. In this study, we were carried out to investigate the constituents of inhibiting a drug metabolizing enzyme CYP3A4 from Zanthoxylum Peel. CYP3A4 is known as an enzyme involved in drug metabolism as monooxygenase containing the heme. As a result of experiment, we found that bergapten ($IC_{50}=18.21{\mu}M$) and quercetin ($IC_{50}=17.27{\mu}M$) isolated from EtOAc extract of Zanthoxylum Peel showed remarkable CYP3A4-inhibiting activities. Structures of the isolated active compounds were established by chemical and spectroscopic means.