• 한국IT서비스학회지
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• 제15권2호
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• pp.169-184
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• 2016

Smartphone use is rapidly spreading due to the advantage of being able to connect to the Internet anytime, anywhere--and mobile app development is developing accordingly. The characteristic of the mobile app market is the ability to launch one's app into foreign markets with ease as long as the platform is the same. However, a large amount of prior research asserts that consumers behave differently depending on their culture and, from this perspective, various studies comparing the differences between consumer behaviors in different countries exist. Accordingly, this research, which uses online product reviews (OPRs) in order to analyze the cultural differences in consumer behavior comparatively by nationality, proposes to compare the U.S. and South Korea by selecting ten apps which were released in both countries in order to perform a sentimental analysis on the basis of star ratings and, based on those ratings, to interpret the sentiments in reviews. This research was carried out to determine whether, on the basis of ratings analysis, analysis of review contents for sentiment differences, analysis of LDA topic modeling, and co-occurrence analysis, actual differences in online reviews in South Korea and the U.S. exist due to cultural differences. The results confirm that the sentiments of reviews for both countries appear to be more negative than those of star ratings. Furthermore, while no great differences in high-raking review topics between the U.S. and South Korea were revealed through topic modeling and co-occurrence analyses, numerous differences in sentiment appeared-confirming that Koreans evaluated the mobile apps' specialized functions, while Americans evaluated the mobile apps in their entirety. This research reveals that differences in sentiments regarding mobile app reviews due to cultural differences between Koreans and Americans can be seen through sentiment analysis and topic modeling, and, through co-occurrence analysis, that they were able to examine trends in review-writing for each country.

• Nuclear Engineering and Technology
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• 제46권2호
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• pp.147-158
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• 2014

In order to investigate how the microstructure of fuel/matrix-interaction (FMI) layers change during irradiation, different U-7Mo dispersion fuel plates have been irradiated to high fission density and then characterized using scanning electron microscopy (SEM). Specifially, samples from irradiated U-7Mo dispersion fuel elements with pure Al, Al-2Si and AA4043 (~4.5 wt.%Si) matrices were SEM characterized using polished samples and samples that were prepared with a focused ion beam (FIB). Features not observable for the polished samples could be captured in SEM images taken of the FIB samples. For the Al matrix sample, a relatively large FMI layer develops, with enrichment of Xe at the FMI layer/Al matrix interface and evidence of debonding. Overall, a significant penetration of Si from the FMI layer into the U-7Mo fuel was observed for samples with Si in the Al matrix, which resulted in a change of the size (larger) and shape (round) of the fission gas bubbles. Additionally, solid fission product phases were observed to nucleate and grow within these bubbles. These changes in the localized regions of the microstructure of the U-7Mo may contribute to changes observed in the macroscopic swelling of fuel plates with Al-Si matrices.

• Nuclear Engineering and Technology
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• 제45권7호
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• pp.827-838
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• 2013

Interaction layer growth between U-Mo alloy fuel particles and Al in a dispersion fuel is a concern due to the volume expansion and other unfavorable irradiation behavior of the interaction product. To reduce interaction layer (IL) growth, a small amount of Si is added to the Al. As a result, IL growth is affected by the Si content in the Al matrix. In order to predict IL growth during fabrication and irradiation, empirical models were developed. For IL growth prediction during fabrication and any follow-on heating process before irradiation, out-of-pile heating test data were used to develop kinetic correlations. Two out-of-pile correlations, one for the pure Al matrix and the other for the Al matrix with Si addition, respectively, were developed, which are Arrhenius equations that include temperature and time. For IL growth predictions during irradiation, the out-of-pile correlations were modified to include a fission-rate term to consider fission enhanced diffusion, and multiplication factors to incorporate the Si addition effect and the effect of the Mo content. The in-pile correlation is applicable for a pure Al matrix and an Al matrix with the Si content up to 8 wt%, for fuel temperatures up to $200^{\circ}C$, and for Mo content in the range of 6 - 10wt%. In order to cover these ranges, in-pile data were included in modeling from various tests, such as the US RERTR-4, -5, -6, -7 and -9 tests and Korea's KOMO-4 test, that were designed to systematically examine the effects of the fission rate, temperature, Si content in Al matrix, and Mo content in U-Mo particles. A model converting the IL thickness to the IL volume fraction in the meat was also developed.

• Nuclear Engineering and Technology
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• 제55권4호
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• pp.1300-1309
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• 2023

Simulated debris was synthesized using UO₂, Zr, and stainless steel and a heat treatment method under inert or oxidizing conditions. The primary U solid phase of the debris synthesized at 1473 K under inert conditions was UO₂, whereas a (U, Zr)O₂ solid solution formed at 1873 K. Under oxidizing conditions, a mixture of U₃O₈ and (Fe, Cr)UO₄ phases formed at 1473 K, whereas a (U, Zr)O_2+x solid solution formed at 1873 K. The leaching behavior of the fission products from the simulated debris was evaluated using two methods: the irradiation method, for which fission products were produced via neutron irradiation, and the doping method, for which trace amounts of non-radioactive elements were doped into the debris. The dissolution behavior of U depended on the properties of the debris and aqueous solution for immersion. Cs, Sr, and Ba leached out regardless of the primary solid phases. The leaching of high-valence Eu and Ru ions was suppressed, possibly owing to their solid-solution reaction with or incorporation into the uranium compounds of the simulated debris.

• 대한수학회지
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• 제34권1호
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• pp.23-42
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• 1997

A 6-dimensional sphere considered as a homogeneous space $G_2/SU(3)$ where $G_2$ is the group of automorphism of the octonians O. From this representation, we can define an almost comlex structure on a 6-dimensional sphere by making use of the vector cross product of the octonians. Also it is known that a homogeneous space $G_2/U(2)$ coincides with the Grassmann manifold of oriented 2-planes of a 7-dimensional Euclidean space.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2002년도 춘계학술대회 논문집
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• pp.179-180
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• 2002

사회가 고도록 발달하면서 사람들의 생활공간은 대부분 사무실이나 가정에서 보내는 시간이 하루의 80-90% 이상을 차지하고 있다. 대부분의 시간을 특정공간에서 보내게 되므로 건강과 편리함을 위해 설치되고 있는 가구나 카펫, 그리고 기타 다양한 제품에서 방출되는 휘발성 유기화합물에 대한 관심이 증가하고 있다. 한 예로, 미국 소비자 생산품 안전 위원회 (U.S. Consumer Product Safety Commission, CPSC)는 1988년부터 1990년 초까지 206가구에서 335명의 주민들로부터 새로 설치된 카펫에서 방출되는 다양한 화학물질로 인한 여러 가지 고통을 접수하였다. (중략)

• 생약학회지
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• 제29권2호
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• pp.75-78
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• 1998

In the course of phytochemical studies for the aerial parts of Ajuga multiflora, one flavonoid and two iridoid glycosides were isolated and identified as apigenin (1), 8-O-acetylharpagide (2) and harpagide (3) on the basis of spectroscopic evidence.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2005년도 추계학술발표회
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• pp.300-301
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• 2005

• 무역상무연구
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• 제38권
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• pp.265-302
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• 2008

This paper intends to analyse some legal issues on "Zeroing" which is based on the article 2.4.2 under the WTO Anti-dumping Agreement. "Zeroing" stands for a specific methodology in calculating a general dumping margin for a product in question under which negative individual dumping margins are treated as zero (thus "zeroed") before aggregating all individual dumping margins. The article 2.4.2 of the Anti-dumping Agreement regulates three types of calculating methodology on dumping margin as first symmetrical method(average-to-average: A-A), second symmetrical method(individual-to-individual: I-I) and asymmetrical method(average-to-individual: A-I). However, this article does not have any provisions about the "Zeroing" practice. In their anti-dumping practices, the EC and the United-States calculated dumping margin based on the "Zeroing", but this methodology has been disputed in the Dispute Settlement Body(DSB) of the WTO. This paper analysed their legal problems with some WTO cases in particular concerning EC-Bed Linen, U.S.-Softwood Lumber Zeroing, U.S.-Zeroing(EC) and U.S.-Sunset Review(Japan) cases. On the basis of theses analysis, we can therefore ask some questions as follows; To begin with, although the article 2.4.2 of the WTO Anti-dumping Agreement does not clearly refer to the "Zeroing", how do some developing countries, as the U.S.A and the E.U. calculate dumping margin as the "Zeroing"? Secondly, what is the relationship between the symmetrical method and asymmetrical method to the dumping margin? And if we adopt the zeroing method, what is the different rate to anti-dumping margin? Thirdly, although the Panel decided that the zeroing methodology of dumping margin used by th U.S.A in administrative review between the U.S.A and the E.U, why does the Appellate Body made the decision that the american methodology is incompatible with the WTO Anti-dumping Agreement? Lastly, what will be affected the upper decision taken by the Appellate Body to the DDA negotiation of anti-dumping matters? Even though the WTO Appellate made a decision that the zeroing method is incompatible with the principles of the WTO law, this methodology contains a lot of problems. Some members of the WTO as the U.S.A and the E.U did not officially declare this methodology to abandon, and the debate concerned is arguing. Therefore this paper tried to present the adequate solution in order to promote the zeroing methodology in the international anti-dumping system and practices.

• 한국해양바이오학회지
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• 제1권2호
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• pp.63-70
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• 2006

본 연구에서는 U937 인체 백혈병 세포의 증식에 미치는 PTX-2의 영향을 조사한 결과, PTX-2의 처리에 따라 U937 세포는 처리 농도 및 처리 시간 의존적으로 심한 형태적 변형과 함께 증식이 억제되었다. 이러한 PTX-2 처리에 의한 U937 세포의 증식억제는 apoptosis 유발과 관련이 있었으며, 이를 DAPI staining에 의한 apoptotic body 형성, flow cytometry를 이용한 sub-G1 세포 빈도의 정량적 분석을 통하여 확인하였다. 이러한 PTX-2 처리에 의한 U937 세포의 apoptosis 유발은 Bcl-2 family에 속하는 anti-apoptotic 인자인 Bcl-$X_L$의 발현 감소 및 IAPs family에 속하는 유전자들의 선택적 발현 감소와 연관성이 있음을 알 수 있었다. 이상의 결과들은 인체 암세포에서 PTX-2의 항암작용을 이해하는데 중요한 자료가 될 것이고 나아가 PTX-2을 포함한 그와 유사한 항암제 후보물질들의 연구에 있어서 기초 자료로서 사용될 수 있을 것으로 생각된다.