• Journal of Life Science
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• v.18 no.1
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• pp.46-51
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• 2008

This study investigated the effects of Punica granatum L. (PG) ethanol extracts on serum lipid levels in ovariectomized rats. In order to elucidate the effects of PG ethanol extracts on the change of lipid concentration in rats, Sprague-Dawley female rats were randomly assigned to groups as follows: sham-operated rats (sham), ovariectomized control rats (OVX-control), ovariectomized rats supplemented with ethanol extracts of PG seed at 50 mg/kg bw/day (OVX-PS50), ovariectomized rats supplemented with ethanol extracts of PG seed at 200 mg/kg bw/day (OVX-PS200), ovariectomized rats supplemented with ethanol extracts of PG peel at 50 mg/kg bw/day (OVX-PS50), ovariectomized rats supplemented with ethanol extracts of PG peel at 200 mg/kg bw/day (OVX-PP200). PG ethanol extracts were orally supplemented at the level of 1mL per day for 7 weeks. The body weight gain, food intake and food efficiency ratio were not significantly different between groups by t-test. The levels of total-cholesterol and triglyceride in serum were not changed by supplementation of PG ethanol extracts. The level of HDL-cholesterol on serum of the OVX-PS50 and OVX-PS200 groups were similar to the OVX-control group, but the OVX-PP50 and OVX-PP200 groups were higher than sham group. These results suggest that ethanol extracts of PG peel were more effected than those of PG seed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.5
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• pp.749-759
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• 1998

Distribution of zooplankton abundance was studied in the front zone in the East Sea in November, 1996, Averaged total abundance in the front zone was less than that in the nearby cold surface water areas but more than that in the nearby warm surface water areas. The number of taxa was the greatest in the upper layer of mixing. Abundance and the number of tun in the front zone were contributed by the cold water and the warm water, respectively. Inspite of the differences in sampling time (day vs night), the species composition and abundance distribution were similar at two sites within cold or warm water area, However, they were quite different at two sites in the front zone although the sampling time of the day was the same. from this, the history of mixing was believed to be the most important factor for the species composition and abundance distribution in the front zone. Zooplankton distribution in the study area was mainly controlled by the dominant cold water Copepod Species Metridia paoifica, the only taxon that showed significant diet vertical migration. Most other taxa showed no significant diel vortical migration, Seawater temperature also affected zooplankton distribution. Positive correlations in the warm area, weak negative correlations in the cold water area, and no significant correlation in the front zone were obtained in general between the seawater temperature and the abundances of the major taxa.

• Korean Chemical Engineering Research
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• v.50 no.2
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• pp.217-222
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• 2012

The synthesis of dimethyl carbonate(DMC) is a promising reaction for the use of naturally abundant carbon dioxide. DMC has gained considerable interest owing to its versatile chemical reactivity and unique properties such as high oxygen content, low toxicity, and excellent biodegradability. In this study, the synthesis of DMC through the transesterification of ethylene carbonate(EC) with methanol was investigated by using ionic liquid and metal oxide catalysts. The screening test of different catalysts revealed that choline hydroxide ([Choline][OH]) and 1-n-butyl-3-methyl imidazolium hydroxide([BMIm][OH]) had better catalytic performance than metal salts catalysts such as MgO, ZnO and CaO. The effects of reaction parameters such as reaction temperature, MeOH/EC mole ratio, and carbon dioxide pressure on the reactivity of [Choline][OH] catalyst were discussed. High temperature and high MeOH/EC mole ratio were favorable for high conversion of EC. However, the yield of DMC showed a maximum when carbon dioxide pressure was 1.34 MPa, and then it decreased for higher carbon dioxide pressure. Zinc chloride($ZnCl_2$) was used as co-catalyst with the ionic liquid catalyst. The mixed catalyst showed a synergy effect on the EC conversion and DMC yield probably due to the acid-base properties of the catalysts.

• Journal of Life Science
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• v.25 no.4
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• pp.397-405
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• 2015

S-allylcysteine (SAC) is a water-soluble organosulfur compound abundant in the aged garlic extract and has been drawing attention as a diet-derived alternative agent not only for the effects of anti-oxidation and anti-inflammation but also for the prevention and treatment of various types of cancer. However, there is no report about the anticancer effects of SAC on cervical cancer cells. The aim of this study was to analyze the inhibitory effects of SAC on cell proliferation of cervical cancer cell line, HeLa and to examine its effects on the apoptosis and cell cycle as the cellular mechanisms of anti-proliferation. For this, we examined effects of different concentrations of SAC on cell proliferation according to treatment periods. Treatment with SAC not only induced morphological changes but also resulted in the reduction of cell viability and the inhibition of concentration- and time-dependant cell proliferation of HeLa. Furthermore, SAC also induced fragmentation of DNA in both DNA fragmentation and TUNEL assays, and induced cell cycle arrest at the G₂/M phase in cell cycle analysis. These results suggest that SAC inhibits proliferation of HeLa at least in part through the induction of apoptosis and the cell cycle arrest.

• Journal of the HCI Society of Korea
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• v.5 no.1
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• pp.37-43
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• 2010

Twitter has been continuously growing since October, 2006. Especially, not only the users and the number of messages have been increasing but also a new concept in social networking called 'micro blogging' has diffused. Within Korea, service such as 'me2day' has already been introduced and the improvement of internet accessibility within mobile devices is expected to expand the 'micro blogs'. In this point, this research is executed to study the new medium, 'micro blog'. To do so, we collected and analyzed Twitter logs of Korean users. Especially, we were curious about the extreme heavy users using Twitter, despite of the linguistic and cultural barrier of the foreign service. Who they are, why and how they use the 'micro blog'. First, we reviewed the general aspect of followers and messages by collecting a certain number of random samples. Using the Lorenz curve we found out that there was the imbalance within the users and based on this phenomenon we deducted an extreme heavy user group. In order to perform further analysis, log analysis was performed on the extreme heavy users. As the result, the users used multiple mobile and desktop 'Twitter' clients. The usage pattern was similar to that of internet usage time but was used during their "micro" time. The users using 'Twitter' not only to spread messages about important information, special events and emotions, but also as a habitual 'chatting tool' to express ordinary personal chats similar to SMS and IM services. In this research, it is proved that 68% of the total messages were ordinary personal chats. Also, with 24% of the total messages were retweets, we were able to find out that virtually connected 'people' and 'relationships' acted as the dominant trigger of their articulation.

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.5
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• pp.290-303
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• 2003

Modern agriculture has been heavily dependent on chemical fertilizers to meet the food demands of ever increasing population. Progressive depletion of major plant nutrients in soil due to intensive cultivation practices has also necessitated the use of higher dose of chemical fertilizers particularly in soils where the organic matter content is very low. Indiscriminate use of chemical fertilizers and pressure on agriculturists to enhance per area crop yields has led to fast depletion of fossil fuel resources with concomitant increase in the prices of chemical fertilizers and also led to environmental pollution. Hence, the current trend throughout the world is to explore the possibility of using alternate nutrient sources or increasing the efficiency of chemical fertilizers by supplementing them with organic fertilizers and bioinoculants comprising largely microbes like, bacteria, fungi, algae etc to enhance nitrogen and phosphates in the soil thus creating a sustainable agricultural environment. Among the different microbial inoculants or biofertilizers, Azospirillum could be a potential candidate due to its non specific host root colonization. It had the capability to fix $N_2$ in wide pH regimes and even in presence of combined nitrogen. Azospirillum inoculation can increase the crop yield to 10-25% and substitute 25% of recommended doses of nitrogenous fertilizers. Apart from nitrogen fixation, Azospirillum is also involved in the root improvement, the activity which was attributed to an increase in the rate of water and mineral uptake by roots. The ability of Azospirillum to produce phytohormones was reported to enhance the root respiration rate, metabolism and root proliferation. They have also been reported to produce polyhydroxybutyrate, that can be used as a biodegradable thermosplastic. A lot of studies have addressed improvements in enhancing its efficiency to fix nitrogen fixation and hormone production.

• Journal of Korean Philosophical Society
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• v.142
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• pp.265-294
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• 2017

In the early days of human history, the governing groups of rulers needed to justify their rule. The cause of rule became the ruling ideology. In China, the backbone of the ruling ideology was originally referred to as 'Di(帝)' or 'Shangdi(上帝)', who was later replaced by 'Tian(天)', Heaven. So there was a claim that Heaven gave the cause of the rule. This idea is the 'Tianming (天命)' idea. When the Zhou(周) Dynasty took control of the central government, the 'Tianming' idea had had a relatively sophisticated form. It was the 'Zhouli(周禮)' that organized the systematic order of the Zhou Dynasty. After this system collapsed, those who recognized 'Zhouli' as a desirable social system considered the collapse of 'Zhouli' as a situation of turbulent age. It was Qin(秦) State that unified all of the states of the period. However, after the unification, the Qin Dynasty fell sharply. The next dynasty was the Han(漢) Dynasty. The new ruling powers of the Han Dynasty needed to justify their regime. That means that it was necessary to establish the ruling ideology of the Han Dynasty. The representative of the ruling ideology of the Han Dynasty was Dongzhongshu, whose thought was based on Confucianism. His thought was related to "Chunqiugongyangzhuan(春秋公羊傳)", an interpretation of "Chunqiu(春秋)". This interpretation perspective is based on the idea of religious Heaven. Dongzhongshu thought that there were co-communions between Heaven and humans. His thought has the meaning of political theology in which rulers hold the basis of the rulers' sovereignty.

• Journal of Korean Classical Literature and Education
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• no.38
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• pp.37-63
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• 2018

The purpose of this study is to determine in the minor characters in alternative versions of Pansori stories. Because, unlike the variations in the main characters, the changes in the minor characters seemed to clearly reveal the specific reasons to the enjoyers of Pansori literature. Bangja in Chunhyang-jeon serves as a narrator by providing information about characters and events, and enlivens the text by satirizing and ridiculing the feudalism class. He appears in certain narrative unit of Chunhyang-jeon and further expands in the order of encounter unit, farewell unit, and reunion unit. At the encounter unit, he helps the bachelor Lee and Chunhyang meet And in the farewell unit, he urges their separation and goes to Han Yang with his master Lee. At the reunion unit, Chunhyang's letter is delivered to the bachelor Lee. The following can be seen from the information above discussion. First of all, the 'Bangja' acquires the better occupation of stories. The enjoyers have changed that he regards as a important figure. Next, in Chunhyang-jeon, the expansion of the role of the Bangja was done in the direction of converging the few characters such as Mabu, Tongin, and the farmer. Especially, the increase of his proportion in the Pansori works can be related to the expansion of the theatricality. Finally, Bangja's frequency increases in the direction of the whole narrative, but it can not be seen as an increase that his role or function has increased. Because his function as a guide expands, but his function as a critic has diminished.

• Journal of Korean Philosophical Society
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• v.130
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• pp.337-361
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• 2014

The main purpose of this paper is to reconstruct the modern thought of love in terms of Dewey's esthetic experience. In the contemporary Korean society, discussions of love are represented in the two tendencies, scientification of love and idealization of love. In actuality, they support the insistence of impossibility of love by the modern sociologists. The former deals with love as chemical reactions in brain, which is based on physiology and biology. The latter regards hypothetical love through the media as the idea of love and displaces concrete love in reality with it. To see love as the subject catching, understanding, and desiring the object depends upon a narrow concept of experience. It comes from the idea that experience is not doing and suffering in a concrete situation but knowing and understanding the object. In this case, the uniqueness and the qualitativeness with each experience of love are ignored. When these traits of a romantic relationship are disregarded, love cannot help but subordinate to the logic of capitalism. This paper, therefore, attempts to find a new way to understand experience of love, focusing on Dewey's concept of aesthetic experience. I suggest that we can expect the possibility of experience of love if love is experienced in a similar way with aesthetic experience based on emotional interaction, and that the very experience of love leads to growth of our personality. Furthermore, I think this communicative experience makes people to change their community as well as each person's private life.

• Journal of Technology Innovation
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• v.28 no.4
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• pp.151-163
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• 2020

The routinized tasks in the post-COVID era are to be replaced by digital technologies, while there is a high possibility that digital transformation technologies and non-routinized tasks have strong complementarity. In particular, looking at the job composition within Korea's industries, the intensities of routinized works appear to be continuously rising. It suggests that the potential side effects on the labor market caused by the acceleration of digital transformation in the post-COVID era will be greater within Korean innovation system. With this background, this study aims to provide a conceptual framework for dealing with potential crises such as, job polarization and widening gaps between workers in terms of economic earnings, based on an in-depth understanding of the inherent properties of digital transformation that will lead to structural changes in our economic and social system. In particular, focusing on the interaction between digital transformation technology and learning in the post-COVID era, this study attempts to redefine the role of the innovation policy for making a successful transition to a new equilibrium state. In addition, this study examines the institutional conditions of the Korean innovation system which affect the creative learning activities of economic actors to draw policy implications for establishing future-oriented innovation policy. Based on these approaches, this study highlights the importance of coevolution between the skills demand and skills supply to spur inclusiveness of Korean innovation system in the post-COVID era.