• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.30-30
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• 2008

Lead-free piezoelectric ceramics 0.97$(Na_{0.5}K_{0.5})NbO_3$-0.03Ba$(Ti_{1-x}Sn_x)O_3$ [NKN-BTS-x] ceramics doped with 1 mol% $MnO_2$ have been fabricated by a sintering technique with muffling. The $MnO_2$-doped NKN-BTS-x ceramics with x$\leq$0.2 have pure orthorhombic perovskite structure at room temperature. The dense microstructure was developed with grain growth as an increase of amount of Sn. Moreover, the addition of Sn was found to have a significant influence on piezoelectric properties. In particular, the $MnO_2$-doped NKN-BTS-0.1 ceramics showed improved piezoelectric properties of piezoelectric constant ($d_{33}$=145pC/N), relatively large electromechanical coupling factor ($k_p$=43%), dielectic constant (${\varepsilon}^T_{33}/{\varepsilon}_0$=676) dielectric loss (tan$\delta$=1.3%).

• CELLMED
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• v.8 no.4
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• pp.21.1-21.2
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• 2018

The aim of this article is to argue that repeated singing helps to feel 'misery loves company.' Folksong is popular music in the past. Korean folk songs have almost repetitive chorus. The repetitive refrain is made easy for everyone to follow. So, people become comrades who share the chorus together. Repetitive music makes people more intimate and more intimate. So, people feel that they share thoughts and feelings with music. It gives me energy to never give in to destiny. So, they encourage each other to be worth living. They sing together and sympathize and comfort each other's pain. 'Hook song' is the most popular form in these days in Korean music. The form of K-pop (Korean pop), which is gaining popularity worldwide, has many repetitions and concentration of melody. BTS (Bang Tan Sonyundan, Boyband) also tells teens around the world through repetitive melodies that "Let's share our joy and sorrow." This is the highest value of music therapy. BTS is a Korean boy band that has gained a worldwide reputation. Recently, their songs are affecting teenagers all over the world. In this way, the author thinks that the repetition of folk songs was reborn as a 'Hook song' and the repetitive form of music is a good way to give support to anyone. The author thinks this is best accomplished by singing 'misery loves company.'

• Structural Engineering and Mechanics
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• v.72 no.4
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• pp.469-477
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• 2019

The understanding of tool-rock interaction mechanism is of high essence for improving the rock breaking efficiency and optimizing the drilling parameters in mechanical rock breaking. In this study, the tool-rock interaction models of indentation and cutting are carried out by employing the discrete element method (DEM) to examine the rock failure modes of various brittleness rocks and critical indentation and cutting depths of the ductile to brittle failure mode transition. The results show that the cluster size and inter-cluster to intra-cluster bond strength ratio are the key factors which influence the UCS magnitude and the UCS to BTS ratio. The UCS to BTS strength ratio can be increased to a more realistic value using clustered rock model so that the characteristics of real rocks can be better represented. The critical indentation and cutting depth decrease with the brittleness of rock increases and the decreasing rate reduces dramatically against the brittleness value. This effort may lead to a better understanding of rock breaking mechanisms in mechanical excavation, and may contribute to the improvement in the design of rock excavation machines and the related parameters determination.

• Journal of Internet Computing and Services
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• v.21 no.4
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• pp.59-68
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• 2020

The present study aims to explore the influence of BTS, which is popular around the world. Specifically, it aims to look at differences between Korean and Chinese BTS female fandom. Besides, it also explores factors affecting fandom's daily happiness. The study conducted a survey with Korean and Chinese female fans. Findings from surveys suggest that first, there are differences on star attributes, fandom activity and illusory romance between Korean and Chinese female fandom. Specifically, Chinese female fandom's professionalism and artistic attractiveness which are included in star attributes, and illusory romance which is gained in fandom activity are higher than Korean. In addition, Korean female fans actively participated in offline fandom activities, while Chinese female fans actively participated in online fandom activities. Second, it is found that fandom activity, star identification and illusory romance have positive effects on daily happiness. Based on these findings, implication, limitations, and topics for future research are discussed.

• Journal of Embryo Transfer
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• v.21 no.4
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• pp.339-344
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• 2006

This study was to investigate the optimal short-term storage diluents for goat spermatozoa. Semen was collected with electro-ejaculation from two goats. The collected semen was diluted in BTS and centrifuged at 500 g for 5 minutes. The supernatant was discarded and diluted with BTS, Modena or Triladyl$^{(R)}$ and stored at 4 or $17^{\circ}C$ for 8 days. The motility of spermatozoa in BTS and Modena stored at $4^{\circ}C$ was rapidly decreased at day 1. The motility of spermatozoa in BTS at $17^{\circ}C$ was decreased to 30$\sim$45% at day 2. In Modena at $17^{\circ}C$, the inappropriate motility fur artificial insemination (AI) was reached at day 4. The spermatozoa stored in Triladyl$^{(R)}$ at 4 or $17^{\circ}C$ were more viable and higher motility up to day 4. In conclusion, liquid storage of goat spermatozoa in Triladyl$^{(R)}$ at 4 or $17^{\circ}C$ for 4 days showed permissible viability for AI.

• Journal of Life Science
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• v.14 no.1
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• pp.72-81
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• 2004

Sexually matured guppies (Poeiria reticulata) were exposed to TBTCI (0.1, 0.32, 1, 3.2, 10, 25, 32, 50, 75 and 100 $\mug/l$) for 144 hours to determine the bioaccumulation rate and effects on the reproduction and behavior. The ratio of TBT residues to $\SigmaBTs\; (TBT:\SigmaBTs)$ was 67% or higher in all the guppies exposed to TBTCl, and the higher the level of TBTCl exposed, the higher the ratio of TBT:∑BTs, suggesting that the higher the level of TBTCl exposed, the lower the metabolism rate of the fish. TBTCl exposure led to a poor reproductivity and an abnormal sexual behavior in the fish, i.e. a reduced number of the male sexual sigmoid display and of spermatophore in the efferent duct was observed in the fish exposed to 0.1 $\mug/l$ and higher levels of TBTCl, and a decreasing ratio of the testicular spermatophore cyst to the whole germ cell cysts was observed in the fish exposed to 0.32∼10 $\mug/l$)of TBTCl. The reduced ratio of the spermatophore cyst seems to be an effect of the endocrine disrupter inhibiting spermiogenesis. In the fish exposed to 25 $\mug/l$ and higher levels of TBTCl, more serious effects, such as a rapid increase of mortality, the necrosis of most of the germ cells, great damages in Sertoli cells and epithelial cells of the efferent duct, a significant increase of abnormal swimming behavior, and a cessation of feeding were observed, which suggest the acute toxicity of TBTCl inhibiting not only the reproduction and behavior but also the survival of the fish itself.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.19 no.1
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• pp.1-7
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• 2014

Butyltin compounds (BTs) were determined in surface sediment samples from Ulsan Bay in 2009 and 2011, to assess the contamination status and the effectiveness of tributylin (TBT) restriction of Korea. Dibutyltin and TBT concentrations in sediments in 2011 ranged from 19.5 to 980 and 14.2 to 1204 ng Sn $g^{-1}$ dry weight, respectively. The highest TBT concentration was found in a big shipyard complex and the next highest was found in harbor, suggesting that harbor and shipyard activities are a major contamination source of TBT in Ulsan Bay. Concentrations of BTs in Ulsan Bay sediments were significantly lower in 2009 and 2011 than that in 2003 survey previously reported, probably as a consequence of the legislative action in Korea. However, TBT concentrations in sediments still exceeded ecotoxicological values. Therefore, it will be important to monitor and reduce TBT contamination in sediments until the levels fall well below ecotoxicological levels.

• The Journal of the Korea Contents Association
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• v.21 no.4
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• pp.723-733
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• 2021

'Reboot' and 'Homage' are using as creative techniques in traditional storytelling media fields such as movies or dramas, but the possibility of expanding the transmedia story world has not yet been presented. This study was written to present a new concept of transmedia story world expansion type using the 'Reboot' and 'Homage' methods. 'Reboot' and 'Homage' are typical storytelling methods of K-POP idol groups that need to develop content. I selected , , and , which have built their story world, and examined both the narrative creation section and the marketing application section. The result of the study is as follows. First, EXO is an example of a reboot case. They set the original set as 'past' and insert the new storylines. Second, BTS is an example of a character's reboot. They built a story world by paralleling 'Idol BTS' and 'Character BTS'. Third, Wanna One is an example of the original story world's homage. They reorganize the story world of and attracting the attention of the existing audience. Fourth, BTS is an example of other media homage which reinterprets the meaning of BTS characters and story world by using the meaning of classic works.

• Korean Journal of Animal Reproduction
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• v.26 no.1
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• pp.9-16
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• 2002

This study was carried out to investigate the effects of extenders such as Beltsville thawing solution(BTS), Modena and Androhep, preservation temperature and period of liquid boar semen on semen characteristics and reproductive performance. Boars were raised at Swine Artificial Insemination Center in National Livestock Research Institute, Sunghwan, Chungnam, Korea. This experiment was carried out from 1995 to 2000. The results obtained were summarized as follows. 1. Sperm motility in the samples with Androhep and BTS reduced from day 5 and in the samples with Modena reduced from day 3 of storage. pH or 3 extenders varied from 6.24 to 7.04 during day 1 to 5 of storage. Farrowing rate of sows inseminated with liquid boar semen offended with BTs, Modena and Androhep extenders did not show any differences until day f after semen collection. Sows inseminated with Androhep extender had better farrowing rates (P＜0.05) than those with Modena extender at day 1 or 5 after semen collection, but farrowing rates after AI using BTS did not differ compared to those Androhep and Modena. Litter size did not show any differences among the three extenders, but Androhep had the decreased litter size from day i of storage. 2. Motility and normal acrosome of the sperm preserved at 5$^{\circ}C$ did not show any differences until day 4 of storage, but those at 17$^{\circ}C$ changed from day 3 and 4, respectively. Farrowing rate of sows artificially inseminated with liquid boa. semen preserved at 17$^{\circ}C$ had higher, than at 5$^{\circ}C$ (p＜0.05), but there was no significant differences in litter size. Farrowing rates and litter size were decreased from day 2 and day 3 of storage at 17$^{\circ}C$, respectively. Farrowing rate of sows inseminated with the preserved semen at 5$^{\circ}C$ did not changed until day 4, but the litter size at 5$^{\circ}C$ was lower than that at 17$^{\circ}C$.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1172-1175
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• 2007

We have investigated the threshold voltage shifts(${\Delta}Vth$) and drain current level shift (${\Delta}Ids$) in subthreshold region of a-Si:H TFTs induced by DC Bias (Vgs and Vds) - Temperature stress (BTS) condition. We plotted the transfer curves and the ${\Delta}Vth$ contour maps as Vds-Vds stress bias and Temperature to examine the severe damage cases on TFTs. Also, by drawing out the time-dependent transfer curve (Ids-Vgs) in the region of $10^{-8}\;{\sim}\;10^{-13}$ (A) current level, we can estimate the failure time of TFTs in a operating condition.