• Journal of Life Science
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• v.21 no.4
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• pp.534-541
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• 2011

Retinoic acid (RA), a metabolite of vitamin A, is known to regulate dedifferentiation of rabbit articular chondrocytes. The regulatory mechanism of dedifferentiation by RA is not yet understood. Thus, the effect of RA on the regulation of nitric oxide (NO)-induced dedifferentiation was investigated in rabbit articular chondrocytes. RA caused loss of the differentiated chondrocyte phenotype as demonstrated by inhibition of type II collagen expression and proteoglycan synthesis. RA also accelerated NO-induced dedifferentiation in rabbit articular chondrocytes as detected by expression of type II collagen and Sox-9 using Western blot analysis and production of sulfated proteoglycan using Alcain blue staining. Further, RA potentiated NO-induced activation of ERK. Inhibition of ERK with PD98059 (PD) recovered the expression of type II collagen and Sox-9 and production of sulfate proteoglycan in NO-induced dedifferentiated chondrocytes by RA treatment. Our findings suggest that RA accelerates NO-induced dedifferentiation of rabbit articular chondrocytes via the ERK pathway.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.2
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• pp.1032-1037
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• 2011

In this study, simulation and optimization works for a demethanizer column have been performed to obtain ethane and heavier products from a pretreated natural gas stream. Pretreated natural gas feed stream was partially condensed after being precooled by exchanging heat with demethanizer top vapor stream and by using an external refrigeration cycle with a propane refrigerant. Vapor stream was cooled further and partially condensed through a turbo-expander. The power generated from the expansion of turbo-expander was delivered to the compressor for the residue gas compression. Liquid stream was cooled by Joule-Thomson expansion valve and was fed to the middle section of the demethanizer. Recovery percent of ethane for feed natural was set to 80% and methane to ethane molar ratio was fixed as 0.0119. On the other hand, some of the cold heat could be recovered by splitting the feed stream and by exchanging heat with side reboiler in order to reduce the heat duty in the propane refrigeration cycle.

• (The) Research of the performance art and culture
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• no.19
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• pp.61-86
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• 2009

Jainpalkwangdae(慈仁八廣大) of Kyungsan area in Kyungbuk province was restored through over 50 years gap. This play basically has the structure of conflict - reconcillation, which is differentiated from a masque and a tightrope walking. The characters of this play are a nobleman, Malttuki (a servant), a legal wife and a second wife. Their personality is deviant from a existing Korean masque. This weird and artificial appearance may be a problem in the process of restoration. Otherwise, it might be a very different transmission type of masque. Therefore, we need to investigate why Jainpalkwangdae is different from a traditional masque.

• Journal of the Korean Institute of Gas
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• v.9 no.4 s.29
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• pp.17-25
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• 2005

The dealuminated and alkali/alkaline-earth metal exchanged Y-zeolites were prepared as a catalyst. Elemental compositions and structures of the prepared catalysts were analyzed by the various spectroscopic techniques such as inductively coupled plasma-atomic emission spectroscopy(ICP-AES), X-ray fluorescence(XRF) and X-ray diffraction(XRD), and the desorption behaviors of adsorbed species on the catalyst surfaces were investigated via NO-TPD experiment. Comparing with the composition of the starting material of NaY zeolite, the magnitudes of Si/Al ratio in catalytic materials were increased after dealumination. The Si/Al ratio of catalytic materials after dealumination followed by Cs and Ba cation exchange were additionally decreased. Dealumination to catalysts induced a destruction of basic frame due to a detachment of aluminum, which results in reducing framework structure, while increasing non-framework structure. This phenomenon becomes more serious with increasing time of steam treatment and even more significant for the cation exchanged catalysts. In NO-TPD experiments, the desorption peaks of NO which indicates an activity point of catalysts shifted to the low temperature region after dealumination and cation exchange. The desorption peaks of the NO-TPD profiles taken after steam treatment also shifted to the low temperature region as the steam treatment time increased. In dealuminated and cation exchanged Y-zeolites, the catalytic activities were more influenced by exchanged cation and the formation of non-framework structure.

• Aerospace Industry
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• v.85
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• pp.44-45
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• 2004

약 20여년 전 국내에서도 큰 인기를 끌었던 ''''A특공대''''라는 외국 TV드라마를 기억하는지? 그 프로그램의 주인공 중 한 사람인 BA(미스터 T 분)는 전혀 비행기를 탈 수 없는 비행공포증 환자여서 비행기를 탈 일이 있으면 동료들이 수면제를 먹인 후에 타야 했다. 하지만 비행공포증에 시달리는 사람들은 드라마 속 뿐 아니라 우리 주위에도 많이 있다. 어떻게 해야 극복할 수 있을까?

• 건강소식
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• v.35 no.7
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• pp.22-23
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• 2011

날씨가 더운 여름이면 남녀노소 누구나 땀으로 흘린 원기를 보충하기 위해 보양 음식, 찬 음식을 찾게 된다. 그러나 보양 음식은 기름진 육식이 대부분이라 장에 무리를 줄 수 있고 찬 음식은 장에 탈이 날 수 있는데 닭고기는 찬 성질을 가지고 있지만, 장과 위를 보호해 차게 먹어도 탈이 나지 않는 음식이다.

• Proceedings of The Korean Cleft Lip And Palate Association
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• 1998.06a
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• pp.38-38
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• 1998

• Proceedings of the Optical Society of Korea Conference
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• 2005.02a
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• pp.304-305
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• 2005

두께가 있는 물체의 단면영상을 얻는 기술은 현대 영상 기술에서 가장 도전적인 관제 중 하나이다. 특히 광학현미경을 이용해 물체의 단면 영상을 얻기 위해 특정 단면에 초점을 맺을 경우 초점 맺어지지 않은 면으로부터 산란되어오는 빛은 탈 초점잡음(defocused noise)으로 작용한다. 이번 발표에서는 물체의 복소 홀로그램 정보를 광 스케닝 홀로그램 방법을 이용하여 추출하고 그를 수치적인 방법으로 연산해 탈 초점 잡음을 제거한다.

• Proceedings of the Korean Nuclear Society Conference
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• 2004.05a
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• pp.267.2-267.2
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• 2004

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.1 no.2
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• pp.27-65
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• 2006

This study reviews the success cases of National Research&Development Projects such as TDX and CDMA projects at the catching-up stage and FTTH technology development project at the post catching-up stage. First, we investigate why the success model of national R&D projects at the catching-up stage failed to operate properly at the post catching-up stage, and then we propose improved policies for a successful national R&D project at the post-catching up stage. From the comparison of FTTH development case at the post catching-up with TDX and CDMA cases at the catching-up stage, we observed that at the catching-up stage 1) there are high uncertainties in technology development and it is very difficult to establish technology standards, 2) it is difficult to conduct government driven R&D and to develop a market for the technology developed, 3) it is difficult to share a vision among the participants in the H&D consortium, and 4) commercialization of the technology developed from the project was carried out by SMEs and venture businesses with little marketing capabilities. Also, we discuss the national level technology development strategies and the role of the government for a successful national research and develop project at the post catching-up stage.