• Macromolecular Research
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• 제9권3호
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• pp.164-170
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• 2001

Recently in order to describe the complex rheological behavior of polymer melts with long side branches like low density polyethylene, new constitutive equations called the pom-pom equations have been derived by McLeish and Larson on the basis of the reptation dynamics with simplified branch structure taken into account. In this study mathematical stability analysis under short and high frequency wave disturbances has been performed for the simplified differential version of these constitutive equations. It is proved that they are globally Hadamard stable except for the case of maximum constant backbone stretch (λ = q) with arm withdrawal s$\_$c/ neglected, as long as the orientation tensor remains positive definite or the smooth strain history in the now is previously given. However this model is dissipative unstable, since the steady shear How curves exhibit non-monotonic dependence on shear rate. This type of instability corresponds to the nonlinear instability in simple shear flow under finite amplitude disturbances. Additionally in the flow regime of creep shear flow where the applied constant shear stress exceeds the maximum achievable value in the steady now curves, the constitutive equations will possibly violate the positive definiteness of the orientation tensor and thus become Hadamard unstable.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.716-717
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• 2006

Gas release behavior from aluminum and Al 7075 alloy powders during heating in argon was investigated by in-situ gas chromatography. Water vapor, hydrogen, carbon mono-oxide were detected as individual evolution spectra against heating temperature and time. The mechanisms of water and hydrogen evolutions were studied in detail for the determination of effective degassing condition. Magnesium in the alloy powder was found to lower the hydrogen evolution temperature to enhance overall hydrogen release.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.652-656
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• 2004

Crashworthy design of trains is now indispensable procedure in modern railway vehicle design for ensuring the safety of Passengers and crew. It is now widely recognized that a more strategic approach is needed in order to absorb higher level energy in a controlled manner and minimize passenger injuries effectively. The first design step in this strategic approach is the design of the front end structure(so called HE extremities) to absorb a large part of total impact energy and then the structure of passengers non-accommodation zones(so called LE extremities) is designed to absorb the rest of impact energy. In this paper, the passengers entrance door area is selected as the LE(low energy) extremities and the design of the LEE was carried out. The main part of LEE design procedures is the design of energy absorbing tubes. For this purpose, the several tube candidates are introduced and compared to each others with numerical crash simulation.

• 대한심미치과학회지
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• 제13권1호
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• pp.31-39
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• 2004

For the prosthodontic results which are compatible with esthetics to be fulfilled, the first prerequisite would be periodontal intervention and stability, the second one may be functional competency and the ultimate goal should be ascribed to esthetic considerations. Other words, esthetic dentistry is a whole entity which encompasses the biological stability of the periodontium, physical accuracy of the prosthodontic structure and finally, the beauty which can be found in natural dentition. It also implies the harmonized lip line which reveals the well-balanced tooth morphology and health gum profiles (Red-White Esthetics). Largely, there lie some differences in the input system of the 3-dimentional data from the prepared abutments between respective computer-assisted systems available now. But the manufacturing systems (CAM) are very similar between them, to say, comprise numeric control systems with whole 3-dimensional milling units according to the restorations to be made. Now the author is going to present CAD/CAM Zirconia All Ceramic Restoration on the topics for the Red-White Esthetics, periodontal control and maintenance, treatment for the discolored teeth, post & core build-up works for the devitalized teeth, characteristics of the Zirconium oxide All Ceramics, fabrication procedures, clinical considerations and its application to diverse clinical situations.

• 복식문화연구
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• 제20권2호
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• pp.286-293
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• 2012

Years ago, anthropologists gave no attention to clothing and dress; but in the 1980s, a new research agenda was created placing the body surface at center stage (Tranberg-Hansen, 2004). Now culture is seen as a process created through agency, practice, and performance-no doubt, clothing very much has a human element. Just as important, we now understand that the globalization process has both local and global impact. Highest on this local/global interaction is the process of consumption. Certainly we are not surprised by this when we know that clothes may be inspired from France, tech-packed from New York, sourced from all over the world, produced in China, and sold in shops on the other side of the globe.

• 음성과학
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• 제14권3호
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• pp.59-76
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• 2007

The purpose of this study is to investigate the pitch rules of Chinese poetry. Pitch rules are concerned with the high tone and the low tone. Because Chinese poetry is a fixed form of verse, it must keep pitch rules to compose Chinese poetry. But until now there has been no acoustic study of pitch rules of Chinese poetry. So, for the first time the present study investigates pitch rules of Chinese poetry acoustically. Pitch contours were analyzed from the sound spectrogram made by Praat. Results showed that actual pitch patterns did not coincide with theoretical pitch rules in reciting Chinese poetry. Therefore, in studying Chinese classics, the Chinese poetry, which has traditionally been considered to be recited according to original Chinese pitch rules, must now be considered in terms of how pitch rules may have changed over time in Korea since it was first introduce to Korean scholars.

• 천문학회보
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• 제41권1호
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• pp.61.1-61.1
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• 2016

As a new way to explore the universe, astronomers are now performing time-domain astronomy by surveying the universe looking for new transient phenomena and taking movies of the universe with telescopes. Large-area, time-series survey of astronomical objects are uncovering many interesting, fast-changing objects that have now been poorly understood before, such as GRBs, tidal disruption phenomena, and new types of supernova. In order to characterize these new, exciting events, it is very critical to perform follow-up observations, and 1-2m telescopes can effectively contribute to such efforts. Since 2007, our group has been performing follow-up observations of gamma-ray bursts (GRBs) and interesting transients using BOAO and other KASI facilities. Here, we present results from several key transient studies that were done by using BOAO: (1) tidal disruption event Swift J1644+57; (2) SN 2011fe that occurred in M101; and (3) several GRB events. These study demonstrates the usefulness of BOAO as a powerful transient follow-up facility. Finally, we will discuss how BOAO research activities can possibly be bolstered in this newly emerging field of astronomy.

• 한국한의학연구원논문집
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• 제7권1호
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• pp.55-66
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• 2001

According to the customary, naming is done after the subject is in existence. But the name's Hae-ba-ra-gi(해바라기), 향일규(向日葵), 향일화(向日花))' has been used as an alias of Hibiscus manihot L.(닥풀) long before Helianthus annuus L.(sunflower) was brought in to Korea. And now the usage of the name has been conversed since them. Since the incorrect record of '葵藿' and '葵花'as '해바라기' in ${\ulcorner}$조선어사전(朝鮮語辭典)${\lrcorner}$(1920), the mistake has been carried on this must be corrected from now on. Incorrect record of hollyhock(蜀葵花) '해바라기' in ${\ulcorner}$몽유(蒙喩))${\lrcorner}$(1810) took a role in this incorrect trend.

• 한국가스학회지
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• 제8권3호
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• pp.57-62
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• 2004

본 연구는 천연가스 생산기지를 구성하는 설비 가운데 핵심설비라 할 수 있는 LNG 저장탱크의 설계 기술을, 세계에서 다섯 번째로 국내 기술로 설계를 완료하여 건설 중에 있는, OO 생산기지 LNG 저장탱크(용량 ; 14만kl, 형식 : 지상식, $9\%$ Ni강 내조 $\cdot$ Prestressed Concrete 외조) 1기에 대한 공정설비의 설계 적합성과 탱크 외벽에 대한 소화설비의 설계 적합성에 관하여 연구하였다.

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2004년도 추계학술발표대회 논문집
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• pp.187-190
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• 2004

The world has been transfiguring so rapidly thesedays. Especially, Shanghai, the symbol of the modernization of China, its speed is now so transcendental, indeed. A lot of Korean companies have made inroads into the China market so actively. There a building called PosPlaza was investigated by PohangJechul(POSCO) in the financial business trade area of Pudong, Shanghai. It has a main building of thirty-four stories with an industrial of four stories as an office area, which is now perceived as a symbolic architecture of Pudong. As for many employers who needed a large-scale restaurant, it was planned to pursue the convenience, to feel the Korean traditions and the cozy of the sunshine through the large flat window with the simplicity as the people enter the main hall.