• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.8
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• pp.1437-1443
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• 2000

This paper considers a channel estimation technique in a wireless local area network (WLAN) system with complementary code keying (CCK) signaling over multipath fading channels. This scheme uses the maximum correlator output of RAKE receiver for the extraction of the channel parameters. The performance of the proposed detection technique is compared with that of a noncoherent detection technique, and a significant improvement of performance is observed in terms of the bit error probability.

• Proceedings of the IEEK Conference
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• 2001.06e
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• pp.43-46
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• 2001

This paper has been studied a implementation Home Automation by PLM and Telephone system. The PLM is composed of FSK IC-chip and the circuit for the power line communication. In this paper load control was made with PIC16F84A and its communication speed was 1200 baud rates.

• Journal of information and communication convergence engineering
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• v.1 no.3
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• pp.129-132
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• 2003

In this paper, cobalt (Co)-electrode FBAR devices fabricated on seven-layered Bragg Reflectors are presented along with their resonance characteristics. ZnO films are used as the resonating material in FBAR devices where the Co electrode is 3000${\AA}$ thick. All processes are preformed in an RF magnetron sputtering system. As a result of characterization, the resonance characteristics are observed to depend strongly on the quality of ZnO film and Bragg Reflectors. In addition, the FBAR devices with W/$SiO_2$ reflectors show good resonance characteristics in term of return loss and quality-factor (Q-factor).

• ETRI Journal
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• v.38 no.4
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• pp.645-653
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• 2016

This paper demonstrates the performance of a metal-substrate power module with multiple fabricated chips for a high current electrical application, and evaluates the proposed module using a 1.5-kW sinusoidal brushless direct current (BLDC) motor. Specifically, the power module has a hybrid structure employing a single-layer heat-sink extensible metal board (Al board). A fabricated motor driver IC and trench gate DMOSFET (TDMOSFET) are implemented on the Al board, and the proper heat-sink size was designed under the operating conditions. The fabricated motor driver IC mainly operates as a speed controller under various load conditions, and as a multi-phase gate driver using an N-ch silicon MOSFET high-side drive scheme. A fabricated power TDMOSFET is also included in the fabricated power module for three-phase inverter operation. Using this proposed module, a BLDC motor is operated and evaluated under various pulse load tests, and our module is compared with a commercial MOSFET module in terms of the system efficiency and input current.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.475-478
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• 2001

Ex vivo hematopoietic cells can treat patients suffering from hematopoietic malignancies using bone marrow transplantation therapies. A initial cell density of $1.5{\times}10^6cells/ml$ and a growth factors of IL-3(5ng/ml), SCF(5ng/ml) and FL(25ng/ml) result in a 3.6-fold expansion of LTC- IC but a unexpansion of total cells.

• Natural Product Sciences
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• v.2 no.2
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• pp.123-129
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• 1996

Chemical carcinogenesis is associated with the increase of intracellular polyamine levels, and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mouse epidermal ODC activity are essential to skin tumor promotion by TPA. Therefore, for the discovery of new cancer chemopreventive agents, we have evaluated about 73 kinds of natural products to study inhibitory effects against ODC activity induced by TPA in T24 cell culture system. The total methanol extracts of plants fractionated into three layers (hexane, ethyl acetate and water layer) were tested and the hexane fraction of Angelica gigas $(root\;bark,\;IC_{50}:\;7.4\;{\mu}g/ml)$ and the ethyl acetate fraction of Corydalis ternata $(root,\;IC_{50}:\;7.5\;{\mu}g/ml)$ were the most effective on the inhibition of TPA-induced ODC activity, These active fractions are under investigation with further sequential fractionation using column chromatography.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.7
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• pp.576-579
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• 2009

This paper suggests a autonomous linear Li-ion battery charger which can safely distribute power between an external power source(AC adapter, auto adapter, or USB source), battery, and the system load. Depending on an external power source's capability, the charger selects proper charging-mode automatically. The charger IC designed and fabricated on Dongbu HITEC's $0.35{\mu}m$ BCD process with layers of one poly and three metals.

• Proceedings of the KIPE Conference
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• 2011.07a
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• pp.287-289
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• 2011

본 논문은 인피니언 테크놀로지스의 RC-IGBT (Reverse Conducting Isolated Gate Bipolar Transistor)와 SOI 드라이브 IC(Integrated Circuit)를 사용한 DIL(Dual-In-Line) 구조의 저전력 모듈인 CIPOS TM (Control Integrated POwer System) 제품을 소개한다. 이 전력 모듈은 최적의 게이트 구동회로, 트렌치 필드스톱의 RC-IGBT를 사용하여 기존의 IGBT 와 Diode를 사용하는 구조에서 최소화 된 패키지 크기를 사용하여 높은 효율을 구현할 수 있다. 본 논문을 통하여 인버터의 어플리케이션에 적합하게 설계된 전력모듈에 대한 소개와 그 특징 및 시스템 구성을 위한 고려사항에 대하여 기술하였다.

• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.1176-1178
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• 1992

This paper shows enhanced working performance of the battery fork-lift truck by developing the IGBT full bridge dc-dc convertor using one-chip micro-processor. The PWM pulse is generated from a 16 bit one-chip micro-processor for the speed control of DC motor. In order to ensure the operation of IGBT and motor pecewisely, IGBT gate drive circuit was designed by using current limiting IC and hige voltage limit IC. And also It is able to regenerative braking.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.55 no.4
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• pp.224-230
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• 2006

The conventional way to implement a bidirectional converter with boost/buck has been to use two general purpose PWM ICs with a single supply voltage. In this case, when one direction mode is in operation, the other is disabled and the output of the error amplifier of the disabled IC may be saturated to a maximum value or zero. Therefore, during mode transition, a circuit which can disable the switching operation for a certain time interval is required making it impossible to get a seamless transition. In this paper, the limitations of the conventional 42V/14V bi-directional DC/DC converter implemented with general current mode PWM ICs with a single supply voltage are reviewed and a new current mode PWM controller circuit with a dual voltage system is proposed. The validity of the proposed circuit is investigated through simulation. and experiments.