http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Dongoh Lee (검색결과 22 건)
- 무료
- 기관 내 무료
- 유료
-
-
-
Lee, Younghun,Lee, Sungho,Zhao, Xing Guan,Lee, Dongoh,Kim, Taemin,Jung, Hoeryong,Kim, Namsu Techno-Press 2018 Smart Structures and Systems, An International Jou Vol.22 No.2
In the last decade, there has been an exponential increase of scientific interest in smart additive manufacturing (AM) technology. Among the different AM techniques, one of the most commonly applied processes is digital light processing (DLP). DLP uses a digital projector screen to flash an ultraviolet light which cures photopolymer resins. The resin is cured to form a solid to produce parts with precise high dimensional accuracy. During the curing process, there are several process parameters that need to be optimized. Among these, the exposure time affects the quality of the 3D printed specimen such as mechanical strength and dimensional accuracy. This study examines optimal exposure times and their impact on printed part. It was found that there is optimal exposure time for printed part to have appropriate mechanical strength and accurate dimensions. The gel fraction and TGA test results confirmed that the improvement of mechanical properties with the increasing UV exposure time was due to the increase of crosslinked network formation with UV exposure time in acrylic resins. In addition, gel fraction and thermogravimetric analysis were employed to microscopically investigate how this process parameter impacts mechanical performance.
-
-
신동오(DongOh Shin),강전일(Jeonil Kang),양대헌(DaeHun Nyang),이석준(Sokjoon Lee),이경희(KyungHee Lee) 한국통신학회 2014 韓國通信學會論文誌 Vol.39 No.1(네트워크)
스마트폰 사용자의 증가는 이동 통신사업자에게 커피숍, 지하철과 같은 공공장소에 와이파이 핫스팟을 제공함으로써 폭증하는 3/4G 트래픽을 분산시키는 노력을 하게 하였다. 전통적인 무선랜에서의 인증은 서비스 제공자측면에서 설계되었기 때문에, 서비스 이용자는 서비스 제공자에게 자신이 고객임을 증명하는 방식으로 이루어진다. 802.11 표준에서는 802.1X를 이용한 상호인증이 지원되지만, 서비스 이용자는 자신이 접속하려는 무선 AP가 정말 서비스제공자가 설치한 것인지 확인하는 것은 어렵다. 공격자는 사용자들의 개인 정보를 얻어내기 위하여 서비스 제공자가 설치한 AP와 동일한 SSID를 가진 위장 AP를 설치할 수 있다. 이 논문에서는 스마트폰 사용자 입장에서 정상적인 무선 AP를 인증하는 기법에 대해 소개한다. 그리고 이 논문의 제안이 이미 제공된 와이파이 핫스팟에서 보안 플러그인 형태로 잘 동작할 수 있음을 보이고, 이를 실험을 통해 증명한다. The increase of smartphone users have made mobile carriers offload increasingly congested traffic of 3/4G by providing Wi-Fi hot-spots in the public places such as coffee shops and subway stations. In the traditional authentication in WLAN, the users should convince the service providers that they are valid customers before they use WLAN services. Since the authentication protocol is designed for service providers. Even with the mutual authentication based on the IEEE 802.1X, which is supported by IEEE 802.11 standard, it is difficult to be convinced of that the service providers really have installed the WLAN APs, which users are confronted with. An attacker can install rogue APs that masquerade as legitimate APs by copying the SSID, MAC address, etc. in order to obtain users’ private information. In this paper, we introduce a method of authenticating legitimate APs for smartphone users. And we show our proposal can be well utilized for the current Wi-Fi hot-spots as a security plug-in and prove it through our experiments.
-
Younghun Lee,Sungho Lee,Xing Guan Zhao,Dongoh Lee,Taemin Kim,정회룡,Namsu Kim 국제구조공학회 2018 Smart Structures and Systems, An International Jou Vol.22 No.2
In the last decade, there has been an exponential increase of scientific interest in smart additive manufacturing (AM) technology. Among the different AM techniques, one of the most commonly applied processes is digital light processing (DLP). DLP uses a digital projector screen to flash an ultraviolet light which cures photopolymer resins. The resin is cured to form a solid to produce parts with precise high dimensional accuracy. During the curing process, there are several process parameters that need to be optimized. Among these, the exposure time affects the quality of the 3D printed specimen such as mechanical strength and dimensional accuracy. This study examines optimal exposure times and their impact on printed part. It was found that there is optimal exposure time for printed part to have appropriate mechanical strength and accurate dimensions. The gel fraction and TGA test results confirmed that the improvement of mechanical properties with the increasing UV exposure time was due to the increase of crosslinked network formation with UV exposure time in acrylic resins. In addition, gel fraction and thermogravimetric analysis were employed to microscopically investigate how this process parameter impacts mechanical performance.
-
Uterine expression of tight junctions in the Canine uterus
Changhwan Ahn,Da-Hye Shin,Dongoh Lee,Hee Young Kang,Eui-Bae Jeung 충북대학교 동물의학연구소 2015 Journal of Biomedical and Translational Research Vol.16 No.3
Tight junctions (TJs) form continuous intercellular contacts in intercellular junctions. TJs involve integral proteins such as occludin (OCLN) and claudins (CLDNs) as well as peripheral proteins such as zona occludens-1 (ZO-1) and junctional adhesion molecules (JAMs). TJs control paracellular transportation across cell-to-cell junctions. Although TJs have been studied for several decades, comparison of the transcriptional-translational levels of these molecules in canine organs has not yet been performed. In this study, we examined uterine expression of CLDNs, OCLN, junction adhesion molecule-A, and ZO-1 in canine. Expression levels of canine uterine TJ proteins, including CLDN1, 2, 4, 5, JAM-A, ZO-1, and OCLN, were measured using reverse transcription PCR, real-time PCR, and Western blotting, whereas TJs distribution was determined by immunohistochemistry. The mRNA and protein expression levels of OCLN, CLDN-1, 4, JAM-1, and ZO-1 were identified in the uterus. Immunohistochemistry demonstrated that TJs were localized to the endometrium and/or myometrium of the uterus. Our results show that canine TJ proteins, including CLDNs, OCLN, JAM-A, and ZO-1, were expressed in the canine uterus. Taken together, these proteins may perform unique physiological roles in the uterus. Therefore, these findings may serve as a basis for further studies on TJ proteins and their roles in the physiological or pathological condition of the canine uterus.
-
키워드 네트워크 분석을 활용한 어휘 중재 연구 동향 분석
이미경 ( Lee¸ Mikyung ),홍정숙 ( Hong¸ Jeongsuk ),홍성욱 ( Hong¸ Seongwook ),문동오 ( Moon¸ Dongoh ) 대구대학교 한국특수교육문제연구소 2021 특수교육저널 : 이론과 실천 Vol.22 No.3
[목적] 본 연구는 키워드 네트워크 분석을 시행하여 어휘 중재 연구의 동향을 살펴보는 데 목적을 두었다. [방법] 어휘 중재 연구 동향을 알아보기 위해 학술연구정보서비스(RISS)와 한국학술지 인용색인(KCI)의 데이터베이스를 활용하여 어휘 중재 관련 문헌 78편을 최종적으로 수집하였다. 이후 텍스톰을 활용하여 키워드 정제를 시행한 후 키워드 빈도, 가중치(TF-IDF), 키워드의 공출현 빈도(N-gram)를 분석하였다. 1-mood 네트워크를 구축한 후 Ucinet의 Netdraw를 사용하여 핵심어 간의 중심성을 분석하고, 핵심어 연결 구조를 시각화하여 의미를 도출하였다. [결과] 첫째, 어휘 중재 관련 연구가 가장 활발히 이루어진 연도는 2011년과 2016년으로 밝혀졌다. 어휘 중재 관련 논문이 가장 많이 게재된 학술지는 언어치료 연구로 나타났다. 어휘 중재가 실시된 연령은 유아와 초등학교 저학년이 많은 것으로 나타났다. 둘째, 어휘 중재와 관련된 키워드 주요 172개 중 가장 높은 빈도를 나타낸 것은 어휘력 향상과 아동이었다. 어휘 중재 키워드의 가충치 (TF-IDF) 분석 결과 아동이 제일 높았으며, 다음으로 유아의 순으로 나타났다. N-gram(공출현)의 빈도는 어휘력 향상과 아동, 언어발달지체아동과 어휘력 향상이 동시에 높은 순으로 출현하는 것으로 분석되었다. 셋째, 네트워크 중심성을 분석한 결과 총 8개의 그룹군이 도출되었다. 각 그룹은 대상별로 관련 주제가 응집되어 나타났다. [결론] 어휘 중재 관련 연구의 동향을 객관적으로 분석한 본 연구는 향후 어휘 중재 관련 연구의 방향성을 모색하는데 필요한 기초자료로 활용할 수 있을 것이다. [Purpose] This study was to examine the trends of vocabulary intervention research by conducting keyword network analysis. [Method] To investigate the research trends of vocabulary intervention, 78 articles related to vocabulary intervention were collected from the databases of the Academic Research Information Service and the Korean Journal of Citation Index. After keyword refinement was perfomrmed using textome, the keyword frequency, weight, term frequency-inverse document frequency, and keyword co-occurrence frequency (N-gram) were analyzed. [Results] First, 2011 and 2016 were identified to be years in which vocabulary intervention was most active. The journal with the most articles related to vocabulary intervention was Journal of speech & hearing disorders. Moreover, vocabulary intervention was found to be performed was found mostly with infants and lower elementary school students. Second, the keywords “vocabulary improvement” and “children” showed the highest frequency among 172 major keywords related to vocabulary intervention. As a result of the TF-IDF analysis of lexical intervention keywords, “children” was found to have the highest number, followed by infants. As for the frequency of N-gram (co-appearance), the analysis indicated that “vocabulary improvement and children”, “children with language development delay and vocabulary improvement”, and “vocabulary improvement” appeared simultaneously in the highest order. Third, as a result of the network centrality analysis, a total of eight groups were derived. In each group, related keywords were aggregated by subject. [Conclusion] This study, which objectively analyzed the trends of vocabulary intervention-related research, can be used as basic data to explore the direction of vocabulary intervention-related research in the future.
-
신동오(DongOh Shin),강전일(Jeonil Kang),양대헌(DaeHun Nyang),이경희(KyungHee Lee) 한국정보보호학회 2011 정보보호학회논문지 Vol.21 No.1
문자와 숫자의 조합으로 이루어진 패스워드는 외우기 쉽고 사용하기 쉽지만 낮은 복잡도를 가지고 있다. 그렇기 때문에 안전하지 않은 환경에서 키보드와 같은 입력 장치를 통하여 패스워드를 그대로 입력하는 행위는 훔쳐보기와 같은 공격으로 쉽게 노출될 수 있다. 이러한 문제를 극복하고자 사용자 비밀의 형태를 다른 것으로 바꾸거나 복잡한 입력과정을 통하여 인증을 수행하는 방법들이 제안되고 있으나, 보안성과 사용자 편의성에 있어서 적합한 타헙점을 찾지 못하고 있다. S3PAS는 사용자의 편의성을 만족시키면서 훔쳐보기로부터 사용자의 패스워드를 보호할 수 있는 보안성도 갖추었다고 알려진 인증기법이다. 그러나 공격자가 인증 세션을 여러 번 바라본 이후에 얻어낸 정보를 이용하여 인증을 시도하는 교차 공격에 대해서는 고려하지 않았다. 이 논문에서는 S3PAS에 대하여, 인증세션이 여러 번 공격자에게 노출되었을 때 발생할 수 있는 보안문제에 대해서 살펴보고, 사용자 실험과 모의실험을 통하여 이를 확인한다. 또한, 이러한 문제를 극복하기 위한 대안에 대하여 고찰한다. While The passwords that combined with characters and numbers are easy to memorize and use, they have low complexity. Therefore they can easily be revealed by the shoulder-surfing attack when they are inputted through the input devices such like keyboard. To overcome these problems, many new authentication schemes, which change the user secret different form or let users input their secret through the more complex manners, have been suggested, but it is still hard to find the balanced point between usability and security. S3PAS is one of well-known schemes which had both usability and security against shoulder-surfing attack. However, this scheme was not considered about intersection attack that the attacker tried to pass the authentication system after observing several authentication sessions. In this paper, we consider the security problem of S3PAS; what the attacker can do when he can observe the authentication sessions in several times. We contirm it through user study and experiments. And also we consider the alternative that overcomes the problem.
-
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
