• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.134-137
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• 1999

The MC-CDMA(Multi-Code CDMA) systems for handling various data transmission rate which is demanded in the IMT-2000 systems are effective transmission technology, which can provide the higher data service than the conventional IS-95 CDMA systems because a user takes advantage of a number of channels. The receiver of MC-CDMA systems to be provided these data service have to be structured of demodulating simultaneously a number of traffic channels. This paper is designed the merged rake receiver demodulating simultaneously a number of traffic channels in the MC-CDMA systems. The merged rake receiver is to reduce the complexity of receiver resulting a number of channels.

• 디지털산업정보학회논문지
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• 제8권1호
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• pp.147-155
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• 2012

Fountain codes ensure reliability and robustness for time varying channels in wireless communication. In this paper, the concatenated fountain codes for AWGN and slow fading channels are investigated. Wireless system model, which includes the concatenated fountain code and modulation, is proposed. Maximum achievable rate is used for analyzing the performance of the system model for AWGN and fading channels. Belief Propagation (BP) algorithm is used for exploiting the soft information received at the decoder. Simulation results show that, concatenated fountain codes performs significantly better than that of a conventional Fountain codes with large packet lengths for higher Signal to Noise Ratio (SNR) in slow fading channels.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.1821-1824
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• 2008

A novel in-mold packaging process has been developed to manufacture devices with closed channels. In this unified process, fabrication of open channels and forming the rigid cover on top of them are sequentially integrated in the same mold. The entire process is comprised of two phases. In the first phase, the open channels are fabricated under an exquisitely controlled temperature and pressure using the conventional micro injection molding technology. In the second phase, the closed channels are fabricated by conducting the injection molding process using the molded structure with the open channels as a mold insert. As a result, the in-mold technology can eliminate the bonding processes such as heating, ultrasonic or chemical processes for cohesion between the channel and the cover, which have been required in conventional methods.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 합동 추계학술대회 논문집 정보 및 제어부문
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• pp.601-604
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• 2002

In this paper, the timing do-skew modeling for a high speed logic tester channels is developed. The time delay of each channel in a logic tester are different from other channels and it can produce timing error in a test. To get the best timing accuracy in the test with a logic tester, the timing skew must be compensated. The timing skew of channels is due to the difference of time delay of pin-electronics devices composing channels and length of metal line placed on PCB. The expected timing difference of channels can be calculated according to the specifications of pin electronics devices and strip line modeling of PCB. With the calculated delay time, the timing skew compensation circuit has been designed. With the timing skew compensation circuit, the timing calibration of a logic tester can be peformed easily and automatically without other time measuring instruments. The calibration method can then be directly applied to logic testers in mass production lines.

• 한국통신학회논문지
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• 제28권5C호
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• pp.506-513
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• 2003

Most existing space-time coding (STC) schemes have been developed for flat fading channels. To obtain antenna diversity gain, they rely on channel state information (CSI) required at the receiver through channel estimation techniques. This paper proposes a new decision feedback decoding scheme for Alamouti-based space-time block coding (STBC) transmission over time-selective fading channels. In wireless channels, time-selective fading effects arise mainly due to Doppler shift and carrier frequency offset, Modelling the time-selective fading channels as the first-order Gauss-Markov processes, we use recursive algorithms such as Kalman filtering, LMS and RLS algorithms for channel tracking. The proposed scheme consists of the symbol decoding stage and channel tracking algorithms. Computer simulations confirm that the proposed scheme shows the better performance and robustness to time-selectivity.

• 한국통신학회논문지
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• 제33권10A호
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• pp.964-971
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• 2008

본 논문에서는 채널이 시간 및 주파수에서 비선택적일 때를 가정하여 복수의 송신 안테나를 사용하는 SC-FDE(Single Carrier with Frequency Domain Equalization) 시스템에서 순환지연 다이버시티 기술과 위상 회전 기술의 성능을 비교한다. OFDM(Orthogonal Frequency Division Multiplexing) 시스템에서는 위상 회전을 이용하여 시간축에서 변화하는 채널을 만드는 것과 순환지연 다이버시티를 사용하여 주파수 선택적 채널을 만드는 것은 유사한 성능을 보인다. 그러나 SC-FDE 시스템에서는 시간축에서 변화하는 채널을 만드는 것이 주파수축에서 변화하는 채널을 만드는 것보다 더 우수한 성능을 보일 수 있다.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2001년도 학술 발표회 진행표 및 논문초록
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• pp.47-47
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• 2001

Opening of $Ca^{2＋}$ -channels represents the final common pathway for insulin secretion in pancreatic beta-cells and related cell lines. We investigated voltage-sensitive calcium channels (VSCCs) and insulin secretion in RINm5F, an insulinoma cell line derived from rat pancreatic beta-cells. Several types of VSCCs were identified in RINm5f cells： dihydropyridine-sensitive L-type, $\omega$-conotoxin GVIA-sensitive N-type, $\omega$-agatoxin IVA-sensitive P-type channels, and $\omega$-conotoxin MVIIC sensitive Q-type channels.(omitted)

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2001년도 학술 발표회 진행표 및 논문초록
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• pp.36-36
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• 2001

Small conductance $Ca^{2＋}$-activated $K^{+}$ channels (or S $K_{Ca}$ channels) are a group of $K^{＋}$-selective ion channels activated by sub-micromolar concentrations of intracellular $Ca^{2＋}$ independent of membrane voltage. We expressed a cloned S $K_{Ca}$ channel, rSK2, in Xenopus oocytes and investigated the monovalent cation selectivity of the channels. We have used site-directed mutagenesis and macro-channel recordings to identify amino acid residues influencing the ion selectivity.(omitted)d)

• 공학논문집
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• 제5권1호
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• pp.119-133
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• 2004

WDM(Wavelength Division Multiplexing) 광통신망의 노드에서 신호채널들이 분기 결합될 때 잔류채널들의 이득을 일정하게 제어해 주기 위해 고정이득 EDFA를 사용한다. 본 논문에서는 양방향 펌프에 의해 고이득을 가지는 L-band EDFA에서 발진광에 의해 입력변화를 보상해주는 방식으로 고정이득 EDFA를 구현하였다. 여기서 발진방향 및 파장에 따른 잔류채널의 과도응답 특성에 있어서 단파장 후방발진의 경우가 최적임을 확인할 수 있었다.

• 한국유통학회지:유통연구
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• 제1권1호
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• pp.223-237
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• 1996

The emergence of the cable television era has spawned the introduction of many new television programming formats such as all-news channels, movie channels, channels catering to cultural events, channels for women, and many others. One of the new programming formats that is expected to have interesting implications for marketing is the home shopping channel. As we have observed in other countries, this new form of distribution may potentially have a major impact on the traditional retail industry. This paper presents a model of home shopping channel viewing behavior. This model is then used to formulate optimal product presentation strategies that may aid managers in the design of home shopping programs. Specifically, by formulating a profit-maximization problem based on tile model, we derive the optimal length of product presentations and explore its properperties through simulating various situations. The discussion of these properties provide insights about making strategic decisions regarding product presentations.