• IEIE Transactions on Smart Processing and Computing
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• 제6권4호
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• pp.276-280
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• 2017

This paper presents computationally efficient image compression for wireless transmission of high-definition video, to adaptively utilize available channel bandwidth and improve image quality. The method indirectly predicts an unknown available channel bandwidth by monitoring encoder buffer status, and adaptively controls a quantization parameter to fully utilize the bandwidth. Experimental results show that the proposed method is robust to variations in channel bandwidth.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -3
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• pp.1463-1466
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• 2002

This paper suggests the effective channel assignment scheme for mobility prediction handover. For maintaining required quality of service (QoS) during handover, there are handover algorithms these reserve the channel where the movement is predicted. But channel assignment schemes these have been studied are not considered mobility prediction handover. This paper suggests the channel assignment scheme that considers mobility predicted handover. The suggested algorithm maintains dropping probability of handover calls, decreases blocking probability of new calls and increases channel utilization.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 통신소사이어티 추계학술대회논문집
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• pp.277-280
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• 2003

In this paper, we analyze the performance of transmitter and receiver of W-CDMA system using the channel coding and space time code in downlink over ITU-R realistic channel model. We can improve the reliability of communications and increase the data rate by channel coding, and we can get a diversity gain by using the space time code over fading channels. We also apply the RAKE receiver to improve tile performance in multi-Path fading channel environment.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.39-40
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• 2006

This paper modeled UWB system transmission channel in indoor environment. For channel modeling, we extracted transmission channel parameter, and then measured from 10MHz to 16.01GHz by using method of CIR(Channel Impulse Response) and CTF(Channel Transfer Function) in small room($5.5{\times}5.5m^2$) environment.

• ETRI Journal
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• 제33권5호
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• pp.806-809
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• 2011

This letter considers the channel estimation for two-way relay MIMO OFDM systems. A least square (LS) channel estimation algorithm under block-based training is proposed. The mean square error (MSE) of the LS channel estimate is computed, and the optimal training sequences with respect to this MSE are derived. Some numerical examples are presented to evaluate the performance of the proposed channel estimation method.

• 유통과학연구
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• 제9권2호
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• pp.31-36
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• 2011

본 논문은 오프라인 채널이 온라인 채널로 사업 영역을 확장할 경우 기존 오프라인 채널의 경쟁적 자산, 이를테면, 브랜드 명성, 서비스 만족도 등이 온라인 채널의 선호도로 연결될 수 있는지를 실증분석을 통해 증명하였다. 연구결과, 오프라인 채널의 브랜드 명성과 서비스 만족도가 오프라인 채널의 선호도에는 직접적으로 긍정적인 영향을 미치고, 온라인 채널의 선호도에는 간접적으로 영향을 미친다. 즉, 오프라인 채널의 경쟁력이 우수할 경우 고객 입장에서는 오프라인 채널의 선호도가 높아져서 거래관계에 대한 몰입과 충성심이 증가한 뒤, 시간적 거리를 두고 오프라인 기업이 확장한 온라인 채널에 대한 선호도 향상으로 발전해 갈 수 있음이 입증되었다. 즉, 오프라인 채널의 경쟁력 향상은 현재와 미래 모두의 사업 기회를 확보하는 데 긍정적 영향을 미치는 것이다. 본 연구의 주요 시사점을 정리하면 다음과 같다. 첫째, 유통 채널의 서비스 품질 관리가 브랜드 명성 관리보다 더욱 중요하다. 고객의 서비스에 대한 체험과 주관적인 평가는 장기적인 브랜드 명성 관리의 선행요소로서 중요할 뿐만 아니라, 채널 선호도에도 더 큰 영향을 미친다. 따라서, 신규 고객을 포함한 일반 고객을 대상으로 하는 광범위한 브랜드 포지셔닝 전략 보다는 기존 우수 고객을 대상으로 하는 서비스 만족도 향상 전략이 더 중요하다는 의미이다. 둘째, 기존의 오프라인 채널이 온라인 채널로서 인터넷쇼핑몰을 구축할 경우 기존의 오프라인 채널의 고객 선호도, 주관적인 평가가 그대로 온라인 채널에도 영향을 미친다는 점이다. 유통기관의 오프라인 채널이 온라인 채널로 확장한 경우뿐만 아니라, 기존의 전통 제조기업이나 서비스 기업이 영업활동의 확장으로서 온라인으로 채널을 확장한 경우도 마케팅 채널의 수직적 통합(Vertical Integration)으로서 유통채널의 확장에 준하여 모두 이에 해당될 수 있다. 셋째, '채널확장'이란 '기업이 자사의 마케팅 활동이나 영업활동의 채널을 증대하기 위하여 온라인 또는 오프라인으로 채널을 확대시키는 의사결정과 그 실행'을 의미하는 것임을 확인할 수 있다. 일반적으로 오프라인 기업의 온라인으로의 채널 확장은 유통채널 확장 그 자체를 위한 목적과 전반적인 경영 프로세스 혁신의 목적 두 가지로 나누어 질 수 있다. 전자는 전통 오프라인 기업의 매출액을 증대하여 수익창출에 기여하기 위함이고, 후자는 주로 오프라인 기업의 비용절감을 통해 수익증대에 기여하기 위함이다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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• pp.211.2-211.2
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• 2015

In order to investigate the effect of front channel in DAL (dual active layer) TFT (thin film transistor), we successfully fabricated DAL TFT composed of ITZO and IGZO as active layer using the solution process. In this structure, ITZO and IGZO active layer were used as front and back channel, respectively. The front channel was changed from 0.05 to 0.2 M at fixed 0.3 M IGZO of back channel. When the mol concentration of front channel was increased, the threshold voltage (VTH) was increased from 2.0 to -11.9 V and off current also was increased from 10-12 to 10-11. This phenomenon is due to increasing the carrier concentration by increasing the volume of the front channel. The saturation mobility of DAL TFT with 0.05, 0.1, and 0.2 M ITZO were 0.45, 4.3, and $0.65cm2/V{\cdot}s$. Even though 0.2 M ITZO has higher carrier concentration than 0.05 and 0.1 M ITZO, the 0.1 M ITZO/0.3 M IGZO DAL TFT has the highest saturation mobility. This is due to channel defect such as pores and pin-holes. These defect sites were created during deposition process by solvent evaporation. Due to these defect sites, the 0.1 M ITZO/0.3 M IGZO DAL TFT shows the higher saturation mobility than that of DAL TFT with front channel of 0.2 M ITZO.

• 신재생에너지
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• 제3권4호
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• pp.8-15
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• 2007

Liquid water in flow channel is an important factor that limits the steady and transient performance of PEM fuel cells. A computational fluid dynamics study based on the volume-of-fluid [VOF] multi-phase model was conducted to understand the two-phase flow behavior of liquid water in cathode gas channels. The liquid water transport in $180^{\circ}{\Delta}$ bends was investigated, where the effects of surface characteristics (hydrophilic and hydrophobic surfaces], channel geometries (rectangular and chamfered corners], and air velocity in channel were discussed. The two-phase flow behavior of liquid water with hydrophilic channel surface and that with hydrophobic surface was found very different; liquid water preferentially flows along the corners of flow channel in hydrophilic channels while it flows in rather spherical shape in hydrophobic channels. The results showed that liquid water transport was generally enhanced when hydrophobic channel with rounded corners was used. However, the surface characteristics and channel geometries became less important when air velocity was increased over 10m/s. This study is believed to provide a useful guideline for design optimization of flow patterns or channel configurations of PEM fuel cells.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 추계학술대회
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• pp.407-410
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• 2006

Selection of flow channel in the separation plate of PEMFC is very important parameter to improve its performance and reduce parasite loss. Flow patterns in the channel have great influence on the transport of hydrogen and all and water generated from electrochemical reaction in diffusion layer In this study, fluid flow in flow channel with parallel and interdigitated patterns are simulated three dimensionally on full flow domain including anode and cathode electrode together. The numerical results show that the fuel cell with interdigitated flow channel represents better performance than that with parallel flow channel due to its strong convective transport across the gas diffusion layer. But the pressure drop in parallel flow channel is much more than that in nterdigitated flow channel. The effect of temperature and stoichiometric number on performance can be calculated and analyzed as well.

• Asian Journal of Business Environment
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• 제9권4호
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• pp.15-22
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• 2019

Purpose: Omni-channel retailing is a new retail phenomenon. Consumers in the omni-channel environment do not rely on one channel but integrate different channels from the same retailers freely during a particular shopping journey. The purpose of this study is to better understand omni-channel shoppers in the fashion retailing context. The present study uses consumer characteristics -- fashion innovativeness, technology innovativeness, and fashion purchase involvement -- as determinants predicting consumers' omni-channel shopping intentions for fashion products. Research design, data, and methodology: Data were collected from 403 U.S. consumers, and the Structural Equation Modeling (SEM) was performed to test proposed hypotheses. The survey for this research consisted of three parts. The first part measured consumer traits in terms of their innovativeness and purchase involvement. The second part was designed to measure consumers' omni-channel shopping intentions, and the third part gathered consumer demographic information. Results: The findings confirmed that fashion innovativeness, technology innovativeness, and fashion purchase involvement positively affected consumers' omni-channel shopping intentions. Conclusions: Fashion retailers should integrate various customer touchpoints and offer mobile-enabled technologies to boost consumer traffic to both online and offline stores. They also need to create a shopping environment that is optimized for customer engagement in various shopping processes and allow them to explore different shopping channel options for best purchase decisions.