• Journal of Internet Computing and Services
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• v.16 no.1
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• pp.101-108
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• 2015

This study paid attention to the notable increase of the use of diet/exercise apps on smartphones. Based on channel expansion theory and technology acceptance model (TAM), this study investigated how three predictors-Internet information use efficacy, Internet information credibility, smartphone use efficacy-affected one's attitude toward and intention to use diet/exercise apps. Results from a path analysis indicated that Internet information use efficacy and smartphone use efficacy positively predict the perceived ease of use of diet/exercise apps. Internet information credibility positively predicts the perceived usefulness of such apps. Moreover, there were gender differences in the effects of both Internet information use efficacy and Internet information credibility on the perceived usefulness of diet/exercise apps.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.331-332
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• 2007

최근 디지털 TV방송서비스의 보급으로 채널의 수와 그에 따른 프로그램의 수가 많아짐에 따라 시청자는 모든 프로그램의 정보를 미리 알고 있는 것이 힘들어 졌다. 모든 채널과 방송 프로그램을 탐색하고 자신의 취향에 맞는 프로그램을 찾아 보기 어려워진 문제를 해결하고자 영화, 상품 등의 분야에 국한 되었던 추천연구 분야도 TV채널 까지 확대할 필요가 있다. 본 논문에서는 사용자의 TV시청 기록을 분석하여 사용자 프로파일 테이블을 구성하고, 베이시안 네트워크와 시계열 분석 이론을 접목하여 추천엔진을 구현하는 TV채널 추천 엔진을 제안한다.

• Journal of Digital Convergence
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• v.15 no.10
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• pp.173-182
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• 2017

On the tourism purchasing stage, this study is focused on analyzing the relationship among tourism omnichannel selecting factor, satisfaction and purchasing intention considering the moderator effects of tourism experience and perceived risk. Based upon antecedent studies and literature about tourism omnichannel, We presented the study model and hypotheses. For the accurate analysis, we did field survey with 400 respondents. The results are as follows. First, the positive relationship are found between channel selecting factors during purchasing and tourism omnichannel satisfaction. Secondly there is a positive relationship between tourism omni-channel satisfaction and tourism purchasing intention. Thirdly tourism experience is proved as a positive moderating effect between channel selecting factors during purchasing and tourism omni-channel satisfaction. But the moderating effect of perceived risk is negative between them.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.9
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• pp.2020-2028
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• 2013

In this paper, we propose a novel analysis and design methodology based on complex network theory for wireless large-scale ad hoc networks. We also enhance the conventional analysis methods which does not sufficiently consider the effect of the wireless communication channels and extend the existing random graph theory by reflecting the wireless communication environments. As a main result, the effect of the network topology such as average degree of each communication node on the network capacity through extensive computer simulations.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.1
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• pp.109-117
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• 2013

Polar codes are the first provable error correcting code achieving the symmetric channel capacity in a wide case of binary input discrete memoryless channel(BI-DMC). However, finite length polar codes have an error floor problem with successive-cancellation list(SCL) decoder. From previous works, we can solve this problem by concatenating CRC(Cyclic Redundancy Check) codes. In this paper we propose to make polar codes having extended-minimum distance from original polar codes without outer codes using correlation with generate matrix of polar codes and that of RM(Reed-Muller) codes. And we compare performance of proposed polar codes with that of polar codes concatenating CRC codes.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.1
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• pp.17-27
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• 2012

Broadcast-based data dissemination has become a widely accepted approach of communication in the mobile computing environment. However, with a large set of data items, the expected delay of receiving a desired data increases due to the sequential nature of the broadcast channel. This paper explores the issue of designing proper data allocation on multiple broadcast channels to reduce this wait time, and proposes a new data allocation scheme named near optimal data allocation(NODA). The proposed scheme first partitions all data items in K group based on the theoretical lower-bound of the average expected delay to determine data items which each broadcast channel has to broadcast. Then, NODA further partitions each group of data items in B groups using extended dynamic programming algorithm to broadcast data items allocated on the same broadcast channel in different frequencies. The proposed scheme is capable of minimizing the average expected delay time since it can broadcast data items allocated on the same channel reflecting their popularities.

• Journal of Broadcast Engineering
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• v.20 no.5
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• pp.667-675
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• 2015

As the interest on the high-definition and high-quality broadcasting is increased, the request on the high quality sound signal is enlarged as well as on the video signal's quality. One factor contributing to the high-quality of audio signal is an expansion of reproduction channels like 10.2channel and 22.2channel, but there is a problem of speaker installation issue of these many channels. One solution to solve this problem, we can use frontal loudspeaker array reproduction technique making virtual surround sound. So in this paper, we introduce theocratical analysis on the Wave Field Synthesis used for speaker array based sound reproduction and also present the result about the subjective listening test of reproduction performance based on this technique to check the perfoemance of this system. As a result, we showed WFS based frontal loudspeaker array reproduction method could provide sufficient performance compared to conventional discrete 5.1 channel reproduction method.

• The Journal of the Korea Contents Association
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• v.18 no.8
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• pp.300-314
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• 2018

This study, expending the existing concept of hostile media perception to biased media perception, empirically examined the effects of TV audience's political disposition(liberal, neutral, conservative) and broadcasting company's political disposition perceived by the audience(liberal, neutral, conservative) on evaluations of the broadcasting channel(interestedness, diversity, creativity, reliability, usefulness, fairness, public interest). With the nationwide online survey data from 624 adult audiences, a broadcasting company evaluated as the most neutral in political disposition at the moments of data gathering was selected and respondents' evaluations of the broadcasting channel were analyzed in a two-way factorial multiple analysis of covariance(MANCOVA). The results showed that the perceived political disposition of the broadcasting company affects audiences' evaluations of the channel while audiences' their own political dispositions do not. In addition, due to the interaction effects between audience's and broadcasting company's political dispositions, congruency in political dispositions led to positive evaluations(congenial media perceptions) while incongruency led to negative ones(hostile media perceptions). Based on these results, theoretical and empirical implications were discussed in terms of the formation of attitudes toward TV broadcasting channels.

• Composites Research
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• v.26 no.6
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• pp.363-372
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• 2013

Numerical simulation for Resin Transfer Molding manufacturing process is attempted by using the eXtended Finite Element Method (XFEM) combined with the level set method. XFEM allows to obtaining a good numerical precision of the pressure near the resin flow front, where its gradient is discontinuous. The enriched shape functions of XFEM are derived by using the level set values so as to correctly describe the interpolation with the resin flow front. In addition, the level set method is used to transport the resin flow front at each time step during the mold filling. The level set values are calculated by an implicit characteristic Galerkin FEM. The multi-frontal solver of IPSAP is adopted to solve the system. This work is validated by comparing the obtained results with analytic solutions. Moreover, a localization method of XFEM and level set method is proposed to increase the computing efficiency. The computation domain is reduced to the small region near the resin flow front. Therefore, the total computing time is strongly reduced by it. The efficiency test is made with a simple channel flow model. Several application examples are analyzed to demonstrate ability of this method.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.3
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• pp.479-485
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• 2006

The double gate(DG) MOSFET is a promising candidate to further extend the CMOS scaling and provide better control of short channel effect(SCE). DGMOSFETs, having ultra thin undoped Si channel for SCEs control, ale being validated for sub-20nm scaling. A novel analytical transport model for the subthreshold mode of DGMOSFETs is proposed in this paper. The model enables analysis of short channel effect such as the subthreshold swing(SS), the threshold voltage roil-off$({\Delta}V_{th})$ and the drain induced barrier lowering(DIBL). The proposed model includes the effects of thermionic emission and quantum tunneling of carriers through the source-drain barrier. An approximative solution of the 2D Poisson equation is used for the distribution of electric potential, and Wentzel-Kramers-Brillouin approximation is used for the tunneling probability. The new model is used to investigate the subthreshold characteristics of a double gate MOSFET having the gate length in the nanometer range $(5-20{\sim}nm)$ with ultra thin gate oxide and channel thickness. The model is verified by comparing the subthreshold swing and the threshold voltage roll-off with 2D numerical simulations. The proposed model is used to design contours for gate length, channel thickness, and gate oxide thickness.