• Bulletin of the Korean Chemical Society
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• v.31 no.10
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• pp.2786-2790
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• 2010

Three new oleanane-type triterpene saponins (1, 2 and 3) were isolated from aerial parts of Gladiolus gandavensis, along with two known compounds (4 and 5). Their structures were elucidated as 29-O-($\beta$-D-glucopyranosyl)-$2{\beta}$,$3{\beta}$-dihydroxyolean-12-en-28-oicacid(1), 3-O-($\beta$-D-xylopyranosyl)-29-O-($\beta$-D-glucopyranosyl)-12-en-28-oic acid (2), and $2{\beta}$,$3{\beta}$,29-trihydroxyolean-12-en-28-oic acid 28-O-[$\beta$-D-glucopyranosyl($1{\rightarrow}2$)-($\alpha$-L-rhamnopyranosyl($1{\rightarrow}6$))-$\beta$-D-glucopyranosyl] ester (3), by spectroscopic methods, and by comparison with known analogues. These oleanane-type triterpene saponins glycosidated at C-29 were not obtained frequently.

• Journal of Microbiology and Biotechnology
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• v.30 no.4
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• pp.515-525
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• 2020

Interferon (IFN)-λ plays an essential role in mucosal cells which exhibit strong antiviral activity. Lactobacillus plantarum (L. plantarum) has substantial application potential in the food and medical industries because of its probiotic properties. Alphacoronaviruses, especially porcine epidemic diarrhea virus (PEDV) and transmissible gastroenteritis virus (TGEV), cause high morbidity and mortality in piglets resulting in economic loss. Co-infection by these two viruses is becoming increasingly frequent. Therefore, it is particularly important to develop a new drug to prevent diarrhea infected with mixed viruses in piglets. In this study, we first constructed an anchored expression vector with CWA (C-terminal cell wall anchor) on L. plantarum. Second, we constructed two recombinant L. plantarum strains that anchored IFN-λ3 via pgsA (N-terminal transmembrane anchor) and CWA. Third, we demonstrated that both recombinant strains possess strong antiviral effects against coronavirus infection in the intestinal porcine epithelial cell line J2 (IPEC-J2). However, recombinant L. plantarum with the CWA anchor exhibited a more powerful antiviral effect than recombinant L. plantarum with pgsA. Consistent with this finding, Lb.plantarum-pSIP-409-IFN-λ3-CWA enhanced the expression levels of IFN-stimulated genes (ISGs) (ISG15, OASL, and Mx1) in IPEC-J2 cells more than did recombinant Lb.plantarum-pSIP-409-pgsA'-IFN-λ3. Our study verifies that recombinant L. plantarum inhibits PEDV and TGEV infection in IPEC-J2 cells, which may offer great potential for use as a novel oral antiviral agent in therapeutic applications for combating porcine epidemic diarrhea and transmissible gastroenteritis. This study is the first to show that recombinant L. plantarum suppresses PEDV and TGEV infection of IPEC-J2 cells.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1911_1912
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• 2009

본 논문에서는 증강현실(Augmented Reality, 이하 AR)을 이용한 PLC 기술교육 시스템을 제안하였다. 제안된 시스템은 PLC 기술 교육 과정을 교사의 지도없이 교육생 스스로가 습득할 때까지 반복 실습이 가능한 시스템이다. 또한, 제안된 시스템은 기초적인 내용의 실습을 3단계로 구성하여 제공함으로써, 각 실습단계의 장비 사용법과 배선 방법이 포함된 교육 내용을 교육생이 자유롭게 실습하도록 하였다.

• Annual Conference of KIPS
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• 2000.10a
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• pp.423-426
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• 2000

본 논문에서는 학생생활지도 활동을 정보기술적 차원에서 보다 효과적으로 지원할 수 있는 방안을 모색하기 위해, 기업에서 적용되고 있는 CRM기법과 학생생활지도기법을 비교하고 검토하였다. 이를 토대로, 학생생활지도활동을 CRM에 관련된 정보기술로써 어떻게 지원할 것인가를 제시하였다.

• Structural Engineering and Mechanics
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• v.57 no.5
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• pp.951-968
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• 2016

Long-span cross-strait bridges extending into deep-sea waters are exposed to complex marine environments. During the construction stage, the flexible freestanding bridge towers are more vulnerable to environmental loads imposed by wind and wave loads. This paper presents an experimental investigation on the dynamic responses of a 389-m-high freestanding bridge tower model in a test facility with a wind tunnel and a wave flume. An elastic bridge model with a geometric scale of 1:150 was designed based on Froude similarity and was tested under wind-only, wave-only and wind-wave combined conditions. The dynamic responses obtained from the tests indicate that large deformation under resonant sea states could be a structural challenge. The dominant role of the wind loads and the wave loads change according to the sea states. The joint wind and wave loads have complex effects on the dynamic responses of the structure, depending on the approaching direction angle and the fluid-induced vibration mechanisms of the waves and wind.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.05a
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• pp.656-659
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• 2015

Recently, due to the standard of a new browser developed by the Google and Mozilla "Service Worker", future users is expected to be able to make use of favorite Web sites offline. Google's is, Web sites have developed a standard of a new browser so as to always respond to user requests. Service Worker, websites that provide space capable of offline work to the user's browser to store various document information, to provide the necessary resources. Then, in order to greatly reduce the data exchange operations between the browser and the server, the speed of the Web page increases. Not only cooks as native app that can use the Web application offline, in that us to also further enhance the characteristics of an existing Web application that is running without installing destructive high technology. Service worker specifications, use experience of Web application is very can be improved, is an innovative technology indicates the version of the web evolve as the future of the platform. Service Worker is not included in HTML5 standard final, is currently being continued standardization. Future Service Worker technology I expect what kind of thing unfolds when applied to the Web browser.

• Journal of Engineering Education Research
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• v.18 no.4
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• pp.45-56
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• 2015

The goal of this study was to analyze the research trends of engineering education in elementary and secondary education. To accomplish this goal, this study analyzed the journal papers by 'published year', 'research topic', 'research subject', 'research method' and 'related school subject'. Followings are the results of this study. First, regarding the published year, the studies related to the elementary and secondary school level engineering education had been conducted 1 to 3 pieces intermittently from 1995 to 2009. And the number of studies are more than 5 pieces after 2010. Second, regarding the research topic, the number of study followed by 'investigation for current status', 'tendency analysis', 'development of teaching method or model', 'verification of teaching method/models' effect'. Third, regarding the research subject, the number of study followed by 'student', 'literature', 'professor', 'teacher'. Fourth, regarding the research method, the number of study followed by 'survey research' and 'literature research', 'qualitative research', 'experimental research' and 'integrated research'. Fifth, regarding the related subject, the number of study followed by 'science', 'technology', 'mathematics', 'practical arts'. Based on the results of this study, there are the needs for further studies to establish theoretical foundation on the engineering content elements in elementary and secondary school level, analyze on related variables and effects, develop engineering assessment instrument, use a variety of research methods, and conduct study on the applications of engineering in math subject.

• Proceedings of the Korea Society of Information Technology Applications Conference
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• 2007.11a
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• pp.133-133
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• 2007

• The Journal of Korean Association of Computer Education
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• v.22 no.3
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• pp.135-146
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• 2019

Big data analysis is actively used for collecting and analyzing direct information on related topics in each field of society. Applying big data analysis technology in education field is increasingly interested in Korea, because applying this technology helps to identify the effectiveness of education methods and policies and applying them for policy formulation. In this paper, we propose our approach of utilizing big data analysis technology in education field. We focus on free semester program, one of the current core education policies, and we analyze the main points of interests and differences in the free semester through analysis and visualization of texts that are written on the operation reports prepared by each school. We compare regional differences in key characteristics and interests based on the free semester operation reports from middle schools particularly at Seoul and Gangwon-do regions. In conclusion, applying and utilizing big data analysis technology according to the needs and requirements of education field is a great significance.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1625-1632
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• 2014

A concise and efficient one-pot synthesis of chroman-2,4-dione-based HKA derivatives by three component reaction of HKAs, triethoxymethane and 4-hydroxycoumarin derivatives under solvent-free and catalyst-free conditions is described. This protocol has many advantages, in that the GAP (Group-Assistant-Purification) chemistry process is involved in this method. As a result, the experimenter can avoid cumbersome process steps such as traditional chromatography and recrystallization purifications. The desired products can be easily obtained by washing the crude products with 95% EtOH.