• Proceedings of the Korea Information Processing Society Conference
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• 2022.05a
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• pp.217-220
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• 2022

디지털 전환 시대를 맞아 일상생활 대부분이 온라인으로 이동하면서 온라인상에서 자신을 나타내는 신뢰할 수 있는 신분증의 필요성이 커지게 되었다. 신원 확인 방법은 중앙 집중식 모델에서 현재는 자기주권신원 모델로 변화하는 과정에 있으며 사용되는 핵심 기술은 탈중앙 식별자 DID(Decentralized Identifier)이다. DID는 기존 신원 체계와 달리 개인의 데이터 소유권을 개인에게 돌려줘 데이터 주권을 지킬 수 있게 해줌으로써 개인의 정보 공유 범위를 결정하는 SSI(Self Sovereign Identity)를 실현하는 기술이다. DID를 이용하면 데이터의 무결성, 투명성을 보장하는 자격 증명(Verifiable Credential, Verifiable Presentation) 발급이 가능하며 이를 검증하는 데이터는 모두 블록체인에 올라가 있는 것이 특징이다. 본 논문에서는 실제 서비스와 유사한 시뮬레이션 환경을 구축하여 자격 증명의 사용자 프라이버시를 보호하는 방법인 BBS+서명 기법에 대해 알아보고자 한다.

• Proceedings of the Korean Society of Computer Information Conference
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• 2020.07a
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• pp.395-396
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• 2020

본 논문에서는 디지털 콘텐츠의 유통과정의 복잡함과 창작자에 대한 권리를 보장하기 위하여 블록체인 기반 플랫폼을 통하여 투명하고 무결성이 보장된 자기권한 관리가 가능하도록 DID(Decentralized Identity)의 적용을 연구하였다. DID의 효율적 적용을 위하여 DID문서와 Verifiable Credential과 presentation의 관리상 특징을 고려하고 DID를 통한 인증과정에서 발생하는 다양한 메타데이터에 대하여 차별화된 암호화 기법적용이 가능하도록 하였다. 본 논문의 연구를 통하여 디지털 콘텐츠에 대한 자기권한 관리가 보다 간단해지고 권리인증 과정 시 안정된 성능 제공이 가능할 것으로 사료된다.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.1
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• pp.30.2-30.2
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• 2021

The extended Lyα nebulae (also known as Lyα blobs or LABs) observed at z=2-6 can provide clues to galaxy formation in the early universe. The connection of LABs with the overdensities of compact Lyα emitters suggests that they are associated with matter density peaks in the universe and thus likely to evolve into the present-day groups and clusters of galaxies. However, the mechanism powering the extended Lyα emission in LABs is remained controversial. The detection of polarization signals that follow the theoretically predicted trend is interpreted as strong evidence supporting that the LABs are caused primarily by the resonance scattering of Lyα originating from star-forming galaxies and AGNs. However, Trebitsch et al. (2016) claimed that the radial profile of polarization could be better explained by the scenario in which Lyα photons are produced in the cooling gas surrounding galaxies and then self-scattered by the gas, rather than by the scattering scenario of photons originating from the central galaxies. In this presentation, using LaRT, a state-of-art Lyα radiative transfer code, it is demonstrated that the observed polarization pattern can be reproduced even with the scattering scenario.

• Clinical Endoscopy
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• v.56 no.4
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• pp.521-526
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• 2023

Portobiliary fistulas are rare but may lead to life-threatening complications. Biliary plastic stent-induced portobiliary fistulas during endoscopic retrograde cholangiopancreatography have been described. Herein, we present a case of portal cavernography and recurrent hemobilia after endoscopic retrograde cholangiopancreatography in which a portobiliary fistula was detected in a patient with portal biliopathy. This likely indicates a change in clinical presentation (from bilhemia to hemobilia) after biliary drainage that was successfully treated by placement of a fully covered, self-expandable metallic stent.

• Korean Journal of Health Education and Promotion
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• v.29 no.2
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• pp.47-58
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• 2012

Objectives: The purpose of this study is to analyze contents of beer advertisements in Korea. Research has suggested the influence of alcohol advertisements on viewer's drinking behavior, attitude, and expectancies. Korea's policy on alcohol advertising relies on limited government regulation and self regulation among alcohol industries. This study is expected to lay a foundation for further discussion on regulating alcohol advertising in Korea. Methods: A total of 81 beer advertisements broadcasted between 2008 and 2011 were analyzed. The contents were categorized into themes (22 themes were used), models, and presentation techniques. Results: The themes most frequently appeared in beer advertisements were quality (66.7%), relaxation (44%), camaraderie (41%), and individuality (39.5%), respectively. Analysis of models revealed that most advertisements had more than three models (64.2%), and most of them were in their 20s (68%). As much as 82% of advertisements used celebrity models. Analysis on presentation techniques showed that 91.4% displayed drinking scenes, and 27% displayed gulping down the whole bottle or the glass. Finally, about 10% of ads showed drinking in hazardous situations such as during water sports. Conclusion: The results of the study reflect the minimal regulation of alcohol advertising in Korea. The need for joint effort by legislators, researchers, alcohol industries, and advertising agencies is discussed in order to establish healthier drinking environment.

• Communications of Mathematical Education
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• v.25 no.1
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• pp.185-205
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• 2011

In this paper, we investigated the mathematical output of a gifted student's independent study. We chose one student who was taking a mentorship course in mathematics at the Gifted Education Center in Chonnam National University, and analyzed the characters of the result which a student showed through the output of independent study and studied the psychological change of a student while he was making a presentation of the results of his study. We found following facts. First, a mentor-independent study improves a mathematical gifted student's inductive thinking and ability to generalize and apply to other cases. Second, presenting a mathematical gifted student's output for mentor-independent study improves his ability of mathematical communication in the abilities of creative problem solving. Finally, there is an increased change in his perception and self-efficacy of mathematics after the presentation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.5
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• pp.559-564
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• 2020

In order to attain the best-educated people in a rapidly changing, modern society with English is an official language, this study applies the problem-based learning (PBL) method to the English Science Class. PBL problems were developed for PBL classes, and their effectiveness has been proven. The focus of this study was five PBL questions posed during the first semester, targeting seven learners in the fourth grade of Elementary School A. The questions were divided into levels aimed at each grade, with the emphasis on specialized English education. Learners wrote journals, peer evaluations, and self-evaluations after finishing their PBL classes. Also, a survey about PBL was conducted after the first semester. The results of the study showed that learners experienced an 86% improvement in presentation skills, an 86% improved interest in learning, 86% better understanding, and 100% improvement in both problem-solving skills and cooperation. On the other hand, learners had difficulty in understanding PBL problems, and with research using the internet. PBL was somewhat unfamiliar to the students, but the survey found that learners are already aware of its effectiveness, and that they are interested in PBL.

• Journal of the Korean Society of Costume
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• v.64 no.8
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• pp.1-19
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• 2014

The purpose of this study is to do an in-depth examination of Korean women in their 30's on the characteristics of their online fashion shopping, clothes-wearing, and presentation. In-depth interview and quantitative analysis were conducted as study methods. Results of this in-depth analysis showed that the factor with the most significant influence in their lifestyle was "childbirth." Childbirth was a major factor during fashion shopping and clothes-wearing. Also the results showed that the reason they used online shopping was for convenience, efficiency, rationality, pursuit of information, variety, and hedonism. In particular, women in their 30's had a higher motivation for efficiency and rationality compared to those in their 20's, and of those women, married working women showed the highest preference for fashion soho malls. Meanwhile, full-time homemakers, who pursued rationality, used open markets to search for fashion items based on price. Furthermore, the factors that women in their 30's considered during online shopping were price, design, purpose or situation for wearing the clothing, respectively. Compared to the women in their 20's, they emphasized recommendation, product properties, credibility, economy more than women in their 20's. Factors such as marriage and childbirth were more influential than occupation. Meanwhile, the factors that women in their 30's considered for wearing and presentation were time, place, and occasion(TPO), which all showed high importance in in-depth interview and quantitative analysis. Other factors were 'suitable image to self' and 'covering up body figure.'

• The Journal of Advanced Prosthodontics
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• v.7 no.6
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• pp.437-445
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• 2015

PURPOSE. A survey was conducted to assess the impact of a TED-like educational session on participants' willingness to accept dental implant therapy. MATERIALS AND METHODS. Volunteers interested in having information about dental implant therapies were recruited and asked to complete a two-part survey before and after an educational session. The initial survey elicited demographic information, self-perceived knowledge on dental implants and willingness to this kind of treatment. A "TED-style" presentation that provided information about dental implant treatments was conducted before asking the participants to complete a second set of questions assessing the impact of the session. RESULTS. The survey was completed by 104 individuals, 78.8% were women and the mean age was $66.5{\pm}10.8$. Before the educational session, 76.0% of the participants refused dental implants mainly due to lack of knowledge. After the educational session, the rejection of dental implants decreased by almost four folds to 20.2%. CONCLUSION. This study proved that an educational intervention can significantly increase willingness to accept treatment with dental implants in a segment of the population who is interested in having information about dental implant therapy. Furthermore, educational interventions, such as TED-like talks, might be useful to increase popular awareness on dental implant therapy.

• Journal of the Korean School Mathematics Society
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• v.1 no.1
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• pp.139-149
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• 1998

The purpose of this study is to check out whether the method that students make problems and anouence them to both students and teacher in the next class influence on the students' intersts, attitudes, logical thinking ability and lerning achievement in mathematics. The following is the experimental design and procedure. First, the author divided students into two groups. One is the experimental group and the other is the control group. These two groups' students consist of the advanced level, the intermediate level and the elementary level according to the students' learning proficiency Second, the author used the different teaching method between the experimental group and the control group. The author gave the experimental group's students the learning assignment problems according to their three levels and made students present the problems to the instructor and classmates in the next class. On the other hand, the author gave the control group's students learning assignment problems according to their three levels, and made them only submit their assingment to the instructor. The results of this study are as follows : 1)The method of solving and presenting the self-made problems on the basis of the informations to solve the given preceding model learning problems according to students' levels made students' learning attitudes more positive even though the method couldn't enhance the students' interests in mathematics. 2)The method of solving and presenting the self-made problems was effective to improve the logical thinking ability for especially the intermediate level's students among the three levels. In addition, the intermediate level's students showed great positive changes in their improvements of the learning achievment. It is assumed that this result is caused by two major factors(reasons). One is students' confidence that they can solve the fundamental problems without difficulty. And the other is students' desire to solve the problems of the intermediate level or more advanced level.