• 한국전기전자재료학회논문지
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• 제18권1호
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• pp.17-23
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• 2005

The switching characteristics of MOS-Controlled Thyristor(MCT) is studied with variation of the channel length and impurity concentration in ON and OFF FET channel. The proposed MCT power device has the lateral structure and P-epitaxial layer in substrate. Two dimensional MEDICI simulator and PSPICE simulator are used to study the latch-up current and forward voltage-drop from the characteristics of I-V and the switching characteristics with variation of channel length and impurity concentration in P and N channel. The channel length and N impurity concentration of the proposed MCT power device show the strong affect on the transient characteristics of current and power. The N channel length affects only on the OFF characteristics of power and anode current, while the N doping concentration in P channel affects on the ON and OFF characteristics.

• Asia Marketing Journal
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• 제16권2호
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• pp.15-38
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• 2014

This paper explores the influence of pursuing goals on customer channel preference in Chinese rural market. With the rapid change in distribution channels and increase in multi-channels, it is necessary to understand the preference for channel choice as well as product choice. This study empirically validated the conceptual framework of the relationship between the pursuing goals and customer channel choice proposed by Balasubramanian, Raghunathan, and Mahajan (2005). Based on the survey data of 232 fertilizer customers in Chinese rural market, this study explores how economic, social, and psychological pursuing goals can impact customer channel preference by mediating variables of product utility and process utility. The results indicate that pursuing goals positively related with product utility and process utility, and product / process utility can mediate the relationship between pursuing goals and customer channel preference positively. Consequently, we can conclude that customers' economic-social-psychological pursuing goals can directly influence customer channel preference via their purchase process utility and product utility. This result also implies that product utility is effective on process utility during consumer's buying decision making, and process utility and product utility are not mutually independent. Therefore, purchase process utility is a "latent driving force" on customer's channel choice decision.

• 한국전기전자재료학회논문지
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• 제24권5호
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• pp.359-363
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• 2011

To integrate the sensor driver and logic circuits, fabricating down scaled transistors has been main issue. At this research, short channel effects were analyzed after n channel polycrystalline silicon thin film transistor was fabricated at high temperature. As a result, on current, on/off current ratio and transconductance were increased but threshold voltage, electron mobility and s-slope were reduced with a decrease of channel length. When carriers that develop at grain boundary in activated polycrystalline silicon have no gate biased, on current was increased with punch through by drain current. Also, due to BJT effect (parallel bipolar effect) that developed under region of channel by increase of gate voltage on current was rapidly increased.

• 한국정보시스템학회지:정보시스템연구
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• 제22권1호
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• pp.181-200
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• 2013

Electronic channel of automobile insurance has emerged as an attractive way of lowering costs and saving time to do the transaction for customers. Electronic channel refers to using web sites to find useful information on insurance products, buy automobile insurance, and ask for services related to the insurance. This study suggests a modified model of the UTAUT and examines the factors influencing intention to use electronic channel in the transaction of automobile insurance. Based on 203 responses from potential automobile insurance buyers, the results showed that performance expectancy, effort expectancy, social influence, service expectancy, and security risk are significantly related to intention to use electronic channel. The results also showed that age as a moderator influences the effects of performance expectancy and effort expectancy on intention to use electronic channel. The study results would improve the understanding of the factors to which managers of insurance companies should pay attention in order to increase their sales through electronic channel.

• 한국통신학회논문지
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• 제33권11C호
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• pp.868-873
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• 2008

본 논문에서는 수직 자기기록 채널에서 연집에러에 따른 LDPC(low density parity check) 부호의 성능을 분석한다. 수직 자기기록 채널에서 연집에러가 발생하면 수신부에서는 채널상태정보(channel state information)를 통하여 연집에러 부분을 알아낸 후 채널검출기의 연판정(Log Likelihood Ratio) 값을 0으로 초기화하는 방법을 사용한다. 패리티 검사 행렬은 부호율이 0.94인 (4336,4096)와 (8672,8192)를 사용한다. 그리고 채널 검출기는 연산량이 적은 SOVA(soft output Viterbi algorithm)를 사용한다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 제14회 신호처리 합동 학술대회 논문집
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• pp.579-582
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• 2001

The performance of a coherent rake receiver of DS-CDMA systems is significantly affected by the accuracy of channel estimation. The performance of the channel estimator can be improved by employing a channel estimation filter (CEF) whose impulse response is adjusted according to the channel condition. In this paper, we consider the design of an adaptive channel estimator for DS-CDMA systems with a pilot channel. The proposed channel estimator estimates the channel condition, which can be performed without haying exact a priori information on the operating condition. The estimated channel condition adjusts the impulse response of the CEF. Numerical results show that the use of the proposed channel estimator can provide BER performance quite robust to a wide range of channel condition.

• 한국통신학회논문지
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• 제36권5B호
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• pp.517-529
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• 2011

본 논문에서는 차세대 해상 통신 시스템인 SANET (Ship Ad-hoc NETwork)의 우선 전송 규격 파라미터를 설정하고, VHF 대역의 실측 해상 채널을 분석하여 SANET 채널 모델링을 수행한다. 또한, 프리앰블, guard time, 파일롯을 포함한 단일 및 다중 반송파 시스템을 위한 프레임 구조를 제안하며, 제안된 프레임 구조 하에서 채널 보상과 채널 부호화 기법에 의한 SANET 시스템의 BER (Bit Error Rate) 성능을 평가 및 분석한다. 결과로 ${\pi}$/4-DQPSK와 ${\pi}$/8-D8PSK를 적용한 단일 반송파 SANET의 경우, differential 변조방식 채택에 의하여 별도의 채널 보상을 하지 않으며, 부호화 이득을 얻을 수 있는 컨볼루션 부호화를 적용하기로 한다. 다중 반송파 SANET의 경우에는 해상환경, 파도에 의한 선박의 움직임 등에 의한 K값의 변화를 고려하여 시스템의 성능을 최대화 하도록 채널 보상 기법과 컨볼루션 부호화를 적용한다.

• 한국의류학회지
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• 제42권6호
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• pp.909-923
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• 2018

Online retailers' offline channel expansion is rapidly growing as an important consumer incentive strategy, despite the enormous initial costs of establishing a store. This study focuses on the offline channel operation of online shopping malls, and examines the effects and influencing factors of the channel expansion strategy from a consumer perspective. In-depth interviews were conducted with ten customers in their 20s and 30s who had visited online retailers' stores or purchased products. Major issues were extracted based on the framework of a channel effect mechanism proposed by Cao and Li (2015). Subsequently, it was found that existing online retailers could enhance brand image and perception by expanding their channels to offline stores. It was also emphasized that the consumer trust on the quality of the product in offline stores is a key variable, and it has a significant influence on consumer's continuous purchase and revisit intention. This study showed that borderless channel integration was the most important task when expanding channels of online retailers. So it will be necessary to strive for an omni-channel strategy so that channel integration can be strategically executed and consumers can interact regardless of channels.

• 전기학회논문지
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• 제59권11호
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• pp.2108-2113
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• 2010

The Long Term Evolution (LTE) system is based on the Orthogonal Frequency Division Multiplexing (OFDM) and relies its channel estimation on the lattice-type pilot samples in the multipath fading channel environment. The estimation of the channel frequency response (CFR) makes use of the least squares estimate (LSE) for each pilot samples, followed by an interpolation both in time- and in frequency-domain to fill up the channel estimates for subcarriers corresponding to data samples. Any interpolation scheme could be adopted for this purpose. Depending on the requirements of the target system, we may choose a simple linear interpolation or a sophisticated one. For any choice of an interpolation scheme, these is a trade-off between estimation accuracy and numerical cost. For those wireless communication systems based on the OFDM and the preamble-type pilot structure, the DFT-based channel estimation and its variants have been successfully. Yet, it may not be suitable for the lattice-type pilot structure, since the pilot samples are not sufficient to provide an accurate estimate and it is known to be sensitive to the location as well as the length of the time-domain window. In this paper, we propose a simple interpolated based on the upsampling mechanism in the multirate signal processing. The proposed method provides an excellent alternative to the DFT-based methods in terms of numerical cost and accuracy. The performance of the proposed technique is verified on a multipath environment suggested on a 3GPP LTE specification.

• JSTS:Journal of Semiconductor Technology and Science
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• 제13권3호
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• pp.213-223
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• 2013

A unified channel thermal noise model valid in all operation regions is presented for short channel MOS transistors. It is based on smooth interpolation between weak and strong inversion models and consistent physical model including velocity saturation, channel length modulation, and carrier heating. From testing for noise benchmark and comparing with published noise data, it is shown that the proposed noise model could be useful in simulating the MOSFET channel thermal noise in all operation regions.