• Development and Reproduction
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• v.3 no.1
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• pp.107-111
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• 1999

To find out the desirable cryoprotectant for cryopreservation of bivalve trochophores, four types of cryoprotectant were tested with trochophores of the pearl oyster (pinctada fucata martensii) generally used in the pearl production in Korea. Each cryoprotectant (dimethyl sulfoxide, ethylene glycol, glycerol and 1,2-propanediol) was mixed with 0.2 M sucrose to make final concentrations of 0.01, 0.1, 1.0 and 2.0 M. The trochophores were immersed in each preparation, waiting for 10 minutes to reach equilibration and cryopreserved in the liquid nitrogen (-l96$^{\circ}C$). Survival rate of trochophores thawed after cryopreservation increased as the media concentration increase. However, a few number of the trochophores seemed to be damaged with the efflux of cell inclusions. Our study rsults indicate that desirable cryoprotectants for cryopreservation of pearl oyster trochophores are 1.0~2.0 M dimethyl sulfoxide and ethylene glycol : 82.8~97.4% of the trochophores cryopreserved with these media survived after thawing.

• Journal of the Korea Society of Computer and Information
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• v.5 no.4
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• pp.7-12
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• 2000

This paper is an attempt to design and implement a multimedia title for the lesson of' Creatu Environment' which appears in the textbook of the second semester for the fourth graders. The title make the most use do multimedia features so that students my be able to reach the best result of activities. The title adopts the Cocktail program developed by Hite-Media Co. It is designed to resolve that are associated with sequential and letter-centered simplicity. As a result, students can interact on the other and the amount of their lessons. The title can effectively combines visual and aural (i. e. information to bring in motivations and participations in learning activities. This title is believed to help students to solve many classroom questions and to try individual learning. Finally, it is hoped that the title helps students to understand the ultimate go subject. 'Environment does affect the life of plants'.

• Journal of Preventive Medicine and Public Health
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• v.44 no.4
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• pp.141-148
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• 2011

Annual epidemics of seasonal influenza occur during autumn and winter in temperate regions and have imposed substantial public health and economic burdens. At the global level, these epidemics cause about 3-5 million severe cases of illness and about 0.25-0.5 million deaths each year. Although annual vaccination is the most effective way to prevent the disease and its severe outcomes, influenza vaccination coverage rates have been at suboptimal levels in many countries. For instance, the coverage rates among the elderly in 20 developed nations in 2008 ranged from 21% to 78% (median 65%). In the U.S., influenza vaccination levels among elderly population appeared to reach a "plateau" of about 70% after the late 1990s, and levels among child populations have remained at less than 50%. In addition, disparities in the coverage rates across subpopulations within a country present another important public health issue. New approaches are needed for countries striving both to improve their overall coverage rates and to eliminate disparities. This review article aims to describe a broad conceptual framework of vaccination, and to illustrate four potential determinants of influenza vaccination based on empirical analyses of U.S. nationally representative populations. These determinants include the ongoing influenza epidemic level, mass media reporting on influenza-related topics, reimbursement rate for providers to administer influenza vaccination, and vaccine supply. It additionally proposes specific policy implications, derived from these empirical analyses, to improve the influenza vaccination coverage rate and associated disparities in the U.S., which could be generalizable to other countries.

• Nuclear Engineering and Technology
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• v.51 no.7
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• pp.1799-1804
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• 2019

The concept of a new method, the CARBEX (CARBonate EXtraction) process, was proposed for reprocessing of spent uranium oxide fuel. The proposed process is based on use of water solutions of $Na_2CO_3$ or $(NH_4)_2CO_3$ and solvent extraction (SE) by the quaternary ammonium compounds for selective recovery and purification of U from the fission products (FPs). Applying of SE allows to reach high degree of purification of U from FPs. Carrying out the processes in poorly aggressive alkaline carbonate media leads to increasing safety of SNF's reprocessing and better selectivity of separation of lanthanides and actinides. Moreover carbonate reprocessing media allows to carry out a recycling and regeneration of reagents. We have been done laboratory scale experiments on the extraction components of simulated voloxidated spent fuel in the solutions of NaOH or $Na_2CO_3-H_2O_2$ and recovery of U from carbonate solutions by SE method using carbonate of methyltrioctylammonium in toluene. It was shown that the purification factors of U from impurities of simulated FPs reached values $10^3-10^5$. The received results support our opinion that CARBEX after the further development can become more safe, simple and profitable method of spent fuel reprocessing.

• Journal of the Korea Convergence Society
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• v.13 no.2
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• pp.143-150
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• 2022

Audio-based SNS also needs a visual guide to reach the contents desired by the users. Therefore, this study investigates visual interface design elements that influence the experience of using audio contents in audio-based SNS. Prior researches have identified that the generally acknowledged interface design elements are important for the usability of audio contents. Through the analysis of the currently launched audio-based SNS, the influence of general interface elements were again confirmed, and via the analysis of other audio content services, a new interface evaluation element was explored. Accordingly, with five general interface evaluation elements-layout, color, icon, typography, graphic image, multimedia elements are newly defined and proposed as crucial factors in evaluating the UI of audio-based SNS.

• Journal of Information Processing Systems
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• v.13 no.3
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• pp.559-572
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• 2017

Cyberbullying has been an emerging issue in recent years where research has revealed that users generally spend an increasing amount of time in social networks and forums to keep connected with each other. However, issue arises when cyberbullies are able to reach their victims through these social media platforms. There are different types of cyberbullying and like traditional bullying; it causes victims to feel overly selfconscious, increases their tendency to self-harm and generally affects their mental state negatively. Such situations occur due to security issues such as user anonymity and the lack of content restrictions in some social networks or web forums. In this paper, we highlight the existing solutions, which are Intrusion Prevention System and Intrusion Detection System from a number of researchers. However, even with such solutions, cyberbullying acts still occurs at an alarming rate. As such, we proposed an alternative solution that aims to prevent cyberbullying activities at a younger age, e.g., young children. The application would provide an alternative method to preventing cyberbullying activities among the younger generations in the future.

• Korean Journal of Medicinal Crop Science
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• v.12 no.5
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• pp.366-371
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• 2004

Aconitine alkaloids produced from cell suspension cultures of Aconitum napellus for the first time. The effects of various culture conditions on cell biomass and aconitine accumulation in cell suspension cultures were investigated. Suspension cell cultures of A. napellus were established by transferring callus tissues from leaf explants onto liquid MS medium supplemented with $1\;mg/l$ NAA and $0.1\;mg/l$ kinetin. Among the culture media tested, MS medium had a pronounced effect on cell growth and aconitine accumulation. The maximum dry cell weight was obtained at inoculum size of 3 g (FCW) per flask and in MS medium supplemented with 5% sucrose after 8 weeks. The addition of salicylic acid (SA) and yeast extract (YE) in the MS medium enhanced aconitine accumulation. Using a proper combination of culture condition and supplements, aconitine content could reach 0.043% (dry weight basis), that was $2.5{\sim}3$ fold higher that detected in control cultures.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.33.2-33.2
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• 2017

Symbiotic stars and quasars show strong far UV resonance doublets including O VI 1032 and 1038, which are known to be major coolants of astrophysical plasma with high temperature T > $10^5K$. We investigate the transfer of $H{\alpha}$ and $Ly{\beta}$ in an emission nebula of temperature T ~ $10^5$, where n=2 population is significant. Line photons of $H{\alpha}$ and $Ly{\beta}$ are transferred in the medium through spatial and frequency diffusion altering their identity according to the branching ratios. We adopt a Monte Carlo technique to describe the transfer of $H{\alpha}$ and $Ly{\beta}$ in an emission nebula with a uniform density and a simple geometrical figure. We find that the temperature of the emission nebula is the major controlling parameter to produce a nonnegligible flux of $Ly{\beta}$. In particular, when T exceeds $10^5K$ the number flux ratio may reach ~ 25% with line center optical depth of a few. We discuss the formation of broad $H{\alpha}$ wings from Raman scattering of $Ly{\beta}$ emergent from a hot emission nebula.

• Transactions of the Korean hydrogen and new energy society
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• v.15 no.2
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• pp.166-174
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• 2004

Purple non-sulfur bacteria, Rhodobacter sphaeroides KD131 grew to reach the maximum cell concentration in 45 hrs of incubation in the synthetic media containing (NH4)2SO4, L-aspartic acid and succinic acid as the carbon and nitrogen sources, respectively, at 30oC under 8 klux irradiance using halogen lamp. The strain produced hydrogen from the middle of the logarithmic growth phase and continued until the cell growth leveled out. The strain grew and produced hydrogen under the irradiance of 3-30 klux, but cell growth was inhibited over 100 klux. In addition, anaerobic/light culture condition was better than the aerobic/dark on the hydrogen production. Among various photo-bioreactors examined, the flat-vertical reactor manufactured using clear acrylic plastic material showed the best hydrogen production rate at the given culture condition.

• Asian review of World Histories
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• v.2 no.1
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• pp.105-127
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• 2014

The Silk Road, a trans-Eurasian network of trade routes connecting East and Southeast Asia to Central Asia, India, Southwest Asia, the Mediterranean, and northern Europe, which flourished from roughly 100 BCE to around 1450, has enjoyed two modern eras of intense academic study. The first spanned a period of little more than five decades, from the late nineteenth century into the early1930s, when a succession of European, Japanese, and American scholar-adventurers, working primarily in Chinese Turkestan (present-day Xinjiang Uyghur Autonomous Region, which comprises China's vast northwest) and China's Gansu Province (to the immediate east of Xinjiang) rediscovered and often looted many of the ancient sites and artifacts of the Silk Road. The second era began to pick up momentum in the 1980s due to a number of geopolitical, cultural, and technological realities as well as the emergence of the New World History as a historiographical field and area of teaching. This second period of fascination with the Silk Road has resulted in not only a substantial body of both learned and popular publications as well as productions in other media but also in an ever-expanding sense among historians of the scope, reach, and significance of the Silk Road.