• Journal of the Korean Vacuum Society
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• v.14 no.4
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• pp.258-262
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• 2005

We report on the field emission properties from vertically aligned carbon nanotubes (CNTs) produced by a triode PECVD with a SiNx capping layer on metal catalyst. It is found that the CNTs density can be controlled by the capping layer thickness and decreases with increasing SiNx thickness. The CNT density of $\~$ 104/$cm^{2}$ exhibited highest electron emission characteristics, the threshold field of 1.2 V/$\mu$m and the current density of 0.17 mA/$cm^{2}$ at 3.6 V/$\mu$m. We have carried out investigation of electron emission stability under ambient gas of N2. The electron emission stability was improved with decreasing CNT density. Under $1\times$$10^{-5}$ Torr ambient pressure, the CNTs in 5 $\mu$m hole show electron emission current higher than $1\times$$10^{-4}$ A/cm2 and it's electron emission uniformity has $2\%$.

• Annual Conference of KIPS
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• 2022.05a
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• pp.513-516
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• 2022

YouTube 이용자의 급증으로 많은 사람이 유튜브 알고리즘에 의해 무분별한 영상에 노출되고 있다. 이는 YouTube 이용자에게 부정적인 영향을 미칠 수 있으며 더 나아가 사회적으로 미성숙한 미디어 문화를 조장할 수 있다. 본 논문에서는 YouTube 컨텐츠에 대한 감정분석 연구를 처음으로 시도한다. 구체적으로, YouTube 컨텐츠 자막에 대해 기존의 자연어 처리 기반 감정분석 기법을 적용하여 성능을 분석한다.

• Composites Research
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• v.14 no.6
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• pp.32-37
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• 2001

It is known that recoating or protection with glass-tube can prevent FBG sensor from being affected by birefringence. However, the effect on the strain transfer of such treatment has not been verified yet. Three types (uncoated, recoated and glass-tube protection) of FBG sensors are fabricated to verify the effect on the strain transfer of each treatment. The strain from each sensor embedded into a graphite/epoxy composite specimen was compared with that of ESG attached on the surface through the tensile test. And the signal characteristics of each sensor were also compared using the tensile test of a tapered aluminum specimen which was under the state of strain gradient.

• The Transactions of the Korean Institute of Power Electronics
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• v.14 no.1
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• pp.31-37
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• 2009

Hybrid ballast for field emission lamp with CNT (carbon nano tube) emitter is proposed. Hybrid ballast consists of a high voltage dc part and hi-polar pulse generation part. Field emission lamp with CNT lamp is composed of three electrodes (anode, gate, and cathode). High voltage dc part is for anode and gate and hi-polar pulse generation part is for gate and cathode in CNT triode respectively. The experimental results demonstrate that the proposed topology is good for driving CNT lamp. To protect the lamp and ballast, OCP (Over Current Protection), OVP (Over Voltage Protection), and OTP (Over Temperature Protection) are added and the experimental results demonstrate that the proposed method is good for driving field emission lamp with CNT emitter.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.2
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• pp.676-684
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• 2021

This study examined how much Korean male middle school students used YouTube to determine if the social support from parents, teachers, and friends might moderate the relationships between YouTube overuse and internalizing and externalizing problems. Three hundred and twenty male middle school students completed questionnaires asking about their YouTube use, levels of YouTube addiction, internalizing and externalizing behaviors, and the degree of social support from parents, teachers, and friends. The results indicated that the YouTube addiction was positively related to the levels of internalizing and externalizing problems. Parental support moderated the relationships between YouTube addiction and internalizing problems. On the other hand, the moderating effects of teachers' or friends' supports were not significant. In contrast, teachers' support was the most crucial moderating factor regarding externalizing problems, while parental and friends' supports were only related to delinquency but not to aggression. These results suggest that the role of parental or teacher supports should be unique depending on the types of problem behaviors. Furthermore, the 'protective effects' of social support were not found in the highly addicted group, suggesting that the early prevention of YouTube overuse is a crucial intervention.

• Journal of the Korea Convergence Society
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• v.13 no.3
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• pp.133-146
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• 2022

Despite the fact that Internet users around the world watch YouTube every day, very few users accurately recognize the recommendation algorithm for search results, and Google and YouTube are not disclosing it. Researchers tried to explore the undisclosed algorithm of YouTube in a reverse engineering design method, find key factors, and check the logical structure in which media platform operators recommend keyword search results and arrange them on the screen. Therefore, researchers studied the basic content priority factors through several months of discussion and data collection, and tried to reverse engineer the influencing factors based on the recommendation results according to male and female gender among the collected keyword search results. Although researchers' design only analyzed some of the almost infinite level of data uploaded and viewed for more than hundreds of hours every hour, these exploratory attempts will study media platform algorithms in the future, understand the intentions of operators, and protect users. thought it could be done.

• Korean Journal of Optics and Photonics
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• v.15 no.5
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• pp.449-454
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• 2004

The optical limiter is an optical component which reduces laser beam intensity for the protection of eyes and light sensors. Carbon nanotube is now known as a highly efficient optical limiting material. Optical limiting effect of the multi-walled carbon nanotube suspensions, in several kinds of solvents such as distilled water, chloroform, ethanol and ethylene glycol, were measured in the range from room temperature to near to the boiling points of the solvents. The pulsed Nd:YAG laser whose wavelength is 1064 nm and pulse duration is 6 ns was used as a light source. The experimental result shows that the limiting efficiency was reduced as the temperature increased, and the suspension which has lower boiling point, viscosity and surface tension has highest efficiency.

• The Journal of the Korea Contents Association
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• v.20 no.10
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• pp.615-629
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• 2020

Conducting Focus Group Interview (FGI), this study examined the roles and discourses of cryptocurrency's online communities and media (legacy media and YouTube), and based on this, the study proposed the direction of cryptocurrency policy. By reviewing previous literature, this study analyzed the characteristics of investors, the online community, and YouTube, which is an investment environment factor. The study figured out the purpose of use and role of the community via interviews with cryptocurrency professional investors and online community members and analyzed main discussion themes of the five top-ranked YouTube channels related to cryptocurrency with the highest number of subscribers. The results suggested that cryptocurrency's investment was led by those who are in their 20s and 30s, the investors preferred and trusted information on new media than legacy media. The online community played the role of emotional homogeneity and empathy, and YouTube mainly performed the informational role. As a result of discourse analysis and interviews, this study argued that the legal stability of cryptocurrency's policy and protection of individual investors are needed. This study's significance indicates that it used various research methods such as literature research, interviews, content analysis of community/YouTube to analyze the informational role and emotional aspects of new media and suggested policy direction of the digital new deal blockchain technology and the fairness of financial industry.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2019.06a
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• pp.291-295
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• 2019

4차 산업혁명과 더불어 1인 미디어 시대를 맞아 개인의 미디어 컨텐츠 제작과 소비가 간편해졌다. 이에, 유튜브, 트위치 등의 플랫폼을 통해 엄청난 양의 미디어 컨텐츠가 생성 소비되고 있다. 이와 관련하여 미디어 컨텐츠의 저작권에 대한 분쟁이 뜨겁다. 특히, 뮤직(음원)컨텐츠의 경우, 동영상을 비롯한 거의 모든 컨텐츠의 제작에 있어 없어서는 안 될 요소로 자리 잡고 있기 때문에 뮤직 컨텐츠와 관련된 저작권 분쟁은 더욱 치열하다. 이에, 본 논문에서는 뮤직 컨텐츠에 대한 저작권 분쟁을 블록체인을 적용하여 해결할 수 있는 방안을 제안한다.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.118-118
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• 2003

홍조류 김속 해조 5종(모무늬돌김, 방사무늬김, 참김, 긴잎돌김, 잇바디돌김)의 사상체를 2단계 냉각법으로 액체질소 중에서 동결보존을 시행하였다. 시료를 여러 가지 동해보호제에 현탁시킨 후 프로그램 냉각기로 4시간에 걸쳐 -4$0^{\circ}C$까지 천천히 동결시켰다. 일차 완만동결 종결 후 즉시 동결용 튜브를 액체질소 중에 수용하여 급속동결 시켰다. 해동시에는 4$0^{\circ}C$의 항온수조에서 대부분의 얼음 결정을 급격히 해동시킨 후 냉각수내에서 완전히 해동시켰다. 생존률은 김 속 해조에서는 neutral red로 염색하여 산정하였으며 50% 해수에 10% DMSO와 0.5M sorbitol 혼합액을 동해보호제로 사용하였을 때의 생존율이 54.6~70.9%였다.