• Journal of the Korea Society of Computer and Information
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• v.18 no.8
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• pp.141-148
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• 2013

Traditional face-to-face university education has shifted its course to combine the advantages of both online and offline education in a blended-learning approach. However, there is still much that is unknown about the actual effect of blended learning, particularly it's learning outcomes in terms of cost effectiveness. This study qualitatively examines the costs and the learning outcomes of blended learning at an on-line college and off-line university. Online college level English pedagogy courses and blended with offline operations at an online university were studied across two semesters in terms of the quality of education, and both direct and indirect cost savings. Other causes for various learning outcomes and cost implications are proposed and validated.

• Journal of Broadcast Engineering
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• v.13 no.5
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• pp.662-676
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• 2008

This paper presents a video copy detection algorithm that blocks online transfer of illegally copied DTV broadcast programs. Particularly, the proposed algorithm establishes a set of keyframes by detecting abrupt changes of luminance, and then exploits the spatio-temporal features of keyframes. Comparing with the preregistered features stored in the database of DTV broadcast programs, the proposed scheme performs a function of video filtering in order to distinguish whether an uploaded video is illegally copied or not. Note that we analyze only a set of keyframes instead of an entire video frame. Thus, it is highly efficient to identify illegal copied video when we deal with a vast size of broadcast programs. Also, we confirm that the proposed technique is robust to a variety of video edit-effects that are often applied by online video redistribution, such as apsect-ratio change, logo insertion, caption insertion, visual quality degradation, and resolution change (downscaling). In addition, we perform a benchmark test in which the proposed scheme outperforms previous techniques.

• Journal of the Korean Home Economics Association
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• v.47 no.5
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• pp.23-34
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• 2009

The purpose of this study was to e${\times}$amine the effect of visual imagery stimulated by product information on consumer responses in online shopping conte${\times}$ts. Dual coding theory provided the theoretical framework of the study. The proposed model of the study was e${\times}$amined by conducting an e${\times}$periment using mock apparel websites with a between-subject factorial design: [2 (pictorial information: detailed views vs. no detailed views) ${\times}$ 2 (verbal information: detailed descriptions vs. abstract descriptions)]. A total of 439 female college students participated in the e${\times}$periment, and 433 responses were ultimately used to test the hypotheses. The findings from the results revealed: (1) the main effects of the pictorial and verbal information on visual imagery, and (2) positive relationships between (a) visual imagery and mood, (b) visual imagery and perceived product quality, (c) mood and perceived product quality, and (d) perceived quality and purchase intentions.

• Journal of the Korea Society of Computer and Information
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• v.28 no.12
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• pp.259-266
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• 2023

In this paper, we propose an algorithm that can improve the accuracy performance of collaborative filtering using attribute-based opinion mining (ABOM). For the experiment, a total of 1,227 online consumer review data about smartphone apps from domestic smartphone users were used for analysis. After morpheme analysis using the KKMA (Kkokkoma) analyzer and emotional word analysis using KOSAC, attribute extraction is performed using LDA topic modeling, and the topic modeling results for each weighted review are used to add up the ratings of collaborative filtering and the sentiment score. MAE, MAPE, and RMSE, which are statistical model performance evaluations that calculate the average accuracy error, were used. Through experiments, we predicted the accuracy of online customers' app ratings (APP_Score) by combining traditional collaborative filtering among the recommendation algorithms and the attribute-based opinion mining (ABOM) technique, which combines LDA attribute extraction and sentiment analysis. As a result of the analysis, it was found that the prediction accuracy of ratings using attribute-based opinion mining CF was better than that of ratings implementing traditional collaborative filtering.

• The Journal of the Acoustical Society of Korea
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• v.40 no.5
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• pp.503-514
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• 2021

Reverberation in speech signals tends to significantly degrade the performance of the Blind Source Separation (BSS) system. Especially in online systems, the performance degradation becomes severe. Methods based on joint diagonalizability constraints have been recently developed to tackle the problem. To improve the quality of separated speech, in this paper, we add the proposed de-reverberation method to the online BSS algorithm based on the constraints in reverberant environments. Through experiments on the WSJCAM0 corpus, the proposed method was compared with the existing online BSS algorithm. The performance evaluation by the Signal-to-Distortion Ratio and the Perceptual Evaluation of Speech Quality demonstrated that SDR improved from 1.23 dB to 3.76 dB and PESQ improved from 1.15 to 2.12 on average.

• 한국HCI학회:학술대회논문집
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• 2007.02a
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• pp.137-142
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• 2007

한정된 주의력 자원을 회복 시키기 위한 방법 중 피드백이 효과가 있는 것으로 보고되고 있다. 그러나 피드백의 구체적 내용에 대한 집중력 회복의 연구는 미미하다. 본 연구는 집중력을 회복할 수 있는 감각적 자극 중 정서적 피드백 간의 효과 차이를 분석 하였다. 집중력을 평가하기 위한 온라인 실험 시스템을 구축하고 시각, 청각, 촉각 피드백 자극을 제시하여 각각의 감각자극과 집중력 회복의 효과를 분석 하였다. 실험 참여자의 감각 피드백의 선호도에 따른 영향 요인을 알아보기 위하여 실험 후 주관적 설문을 실시하였다. 감각 피드백을 6명의 대학원생에게 일주일에 걸쳐 반복적으로 약200개의 자극을 제시하고 5회 이상 실험을 통하여 얻어진 30회 결과를 분석하였다. 결과적으로 피드백 별 수행 수준에서는 청각, 촉각, 시각 순으로 효과가 높았으며, 반응 시간에서는 촉각, 청각, 시각 순으로 효과적으로 나타났다.

• Journal of The Korean Association For Science Education
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• v.39 no.5
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• pp.669-679
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• 2019

In this study, we investigated how 'Scientific Inquiry Experiment,' a newly introduced subject under the 2015 revised curriculum, was implemented to identify the difficulties that science teachers face in the process of teaching the subject and to explore how to support them through online survey and interview methods. A questionnaire of the survey, which consisted of environmental factors of class, preparation and execution of class, teacher self-evaluation of class, and direction for the subject, was developed, and the online survey was requested with a response from one teacher per school from 1674 high schools nationwide. We analyzed the results from 814 teachers who answered all required questions, and we also conducted interviews and online advisory discussions to ensure the validity of our analysis. In the results of the study, teachers complained of lack of time for preparation and execution of the subject, and they demanded laboratory assistants and quality teaching materials. In addition, in order to achieve the goal of the subject, they agreed the necessity of using the 'block scheduling' though they also agreed the difficulties of its implementation. Meanwhile, the alteration of guidelines for evaluation, which was changed from 9-grade system to 3-grade system, was positively recognized by teachers. As a result of this change, the percentage of performance assessment increased in 2019 compared to 2018, but there were no significant changes in the number of 'hands-on activity.' Finally, we proposed ways to support 'scientific inquiry experiment'.

• Information Systems Review
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• v.25 no.4
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• pp.1-25
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• 2023

The online fitness industry has experienced rapid growth in recent years, overcoming physical constraints of conventional fitness programs. The COVID-19 pandemic accelerated the trend as social distancing policies were implemented. However, as financial distress of offline gyms worsened, the Korean government implemented the "With-COVID19" policy, which lifted most of the restrictions and regulations on offline gyms, on November 1st, 2021, raising concerns about the loss of drivers for the growth of the online fitness industry. Using regression discontinuity design in time (RDDiT), this study investigates the causal effect of the "With-COVID19" policy on the viewer engagement of online fitness content. Contrary to expectations that viewer engagement would decrease, it increased by 21%. Additionally, subgroup analysis based on opportunity cost reveals heterogeneity, and the high-cost group experienced a greater increase of 32% compared to low-cost group. Based on these findings, the study provides possible mechanisms of the increase, theoretical contributions on using RDDiT in the Information Systems, and practical implications for guidelines on managing online fitness platforms and content in the era of digital transformation.

• Korean journal of communication and information
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• v.79
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• pp.165-195
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• 2016

This paper aims to examine the third-person effect(TPE) of hate comments on online news, and analyze how the issue-relevant audience factors as well as the characteristics of the online message have influence on the TPE. More specifically, based on the distinction between hateful and logical comments regarding the issue of illegal immigration, the authors have conducted an online experiment that compares how the message-related features, i.e., ways of expressing the ideas, lead to the difference in TPE. Analysis was also conducted with regards to how political orientation and discriminatory predisposition to immigrants among the audiences, have different impacts on the TPE. The 479 participants in the experiments were randomly assigned to experimental group(exposed to hate comments) or control group(exposed to logical comments). The results reveal that the TPE of hate comments is higher than that of logical message. The same message proved to be more effective for news users with liberal orientation and discriminatory predisposition. The significance of this paper lies in that it has examined the effect of online hate comments in a rigorous experimental setting. Also the research further elaborated on the audience-related variables, for which the previous studies tended to focus those on the general psychological level rather than relate them more specifically to the issues.

• Journal of the Korean Home Economics Association
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• v.47 no.9
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• pp.101-110
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• 2009

The purpose of this study was to examine the effect for information load on perceived information quality and website quality, and the relationships among perceived information quality, website quality and behavioral intentions in online apparel shopping contexts. The information load theory provided the theoretical framework for this study. The research strategy employed an online experimentation using an apparel mock website. The total of 647 responses were used for data analyses. The model of the study was tested by MANOVA and SEM. The results of MANOVA revealed the effect of information load on perceived information quality and website quality. The medium level of information load was perceived as having more positive information quality and website quality as compared to the low or high level of information load. The findings of SEM revealed the positive effect of information quality on website quailty, the positive effect of website quality on WOM and willingness to pay more, and the negative effect of website quailty on willingness to switch. Online apparel retailers and website designers need to manage information quantity and quality by understanding the importance of information load.