• Korean journal of communication and information
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• v.56
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• pp.194-218
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• 2011

Focusing on the individuals' structural positions and roles in the internet discussion network, this research explores whether and how the opinion leaders' network characteristics are associated with the message quality and interpersonal influence in terms of attention-drawing and response-generation, which prior studies often failed to fully explicate. Findings suggest that discussion participants with high message quality occupy more central positions in the discussion network, thus enjoy more attention and responses of other following participants. However, opinion leader's network centralities, which tap the structural positions and unique roles in the online discussion network, systematically mediate the effect of the message quality on interpersonal influence. Moreover, significant interaction between opinion perception and network centrality was found only on the majority opinion group, rendering the entire discussion structure toward more enclaved deliberation and group polarization. Taken together, the results imply that the influence of the online opinion leader can only be substantiated with participant's central positions in the discussion network, which has been ignored by the prior opinion leadership research.

• Journal of Korean Home Economics Education Association
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• v.27 no.3
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• pp.79-97
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• 2015

Curriculum may be defined as everything students learn at school or the specific plan of a subject that students are supposed to learn. The purpose and goals of the curriculum or who is in charge of developing the curriculum may differ by country. This study aimed at comparing the mechanisms in which the Home Economics curriculum is implemented in Korea and the Unite States at different levels. Considering that Korean government now supports increased autonomy of schools, allowing them to execute curricula according to their educational environments, it is meaningful that the advantages and disadvantages of the implementation mechanisms of two countries are explored. Specifically, middle schools in a City of Kyung-gi Province in South Korea and three states(Wisconsin, Ohio, and Washington states) in the United States are examined. The curriculum documents at different levels as well as study plans used by actual teachers are compared for this purpose. In case of South Korea, the nation state is in charge of curriculum development and the curriculum document defines the educational contents to detail in order to provide standardized learning experience to students. This type of closely controlled system warrants standardized educational contents and thus allows nation-wide assessment using standardized measures. On the other hand, it is difficult to accommodate diversities among students in terms of aptitudes and learning styles, and also limits creativity enhancement or integrative approach to teaching and learning. In comparison, curriculum in the United States is rather loosely defined, and more autonomy is granted to schools and teachers. Each of these two different systems may have advantages and disadvantages of their own. The findings of this study is expected to provide implications to curriculum development as well as to the development of framework and guidelines to the curriculum implementation.

• Journal of the Korean association of regional geographers
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• v.7 no.3
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• pp.107-120
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• 2001

This study is concerned with providing a reliable procedure of calibrating a set of places specific distance parameters and with applying it to U.S. inter-State migration flows between 1985 and 1900. It attempts to conform to recent advances in quantitative geography that are characterized by an integration of ESDA(exploratory spatial data analysis) and local statistics. ESDA aims to detect the spatial clustering and heterogeneity by visualizing and exploring spatial patterns. A local statistic is defined as a statistically processed value given to each location as opposed to a global statistic that only captures an average trend across a whole study region. Whereas a global distance parameter estimates an averaged level of the friction of distance, place-specific distance parameters calibrate spatially varying effects of distance. It is presented that a poisson regression with an adequately specified design matrix yields a set of either origin-or destination-specific distance parameters. A case study demonstrates that the proposed model is a reliable device of measuring a spatial dimension of migration, and that place-specific distance parameters are spatially heterogeneous as well as spatially clustered.

• Journal of Food Hygiene and Safety
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• v.20 no.1
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• pp.1-6
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• 2005

To investigate whether there are estrogenic and anti-estrogenic activities in various medicinal herbs and discover prominent chemo-preventive agents, we screened and compared the ethanol extracts of 9 plants through the recombinant yeast assay and MCF-7 human breast cancer cell assay, In recombinant yeast assay, seven medicinal herbs showed estrogenicity, and four extracts showed androgenecity. In MCF-7 proliferation assay, the growth of MCF-7 cells was inhibited by eight extracts before and even after co-treatment with bisphenol A. It is interesting that the extracts of Glycyrrhiza uralensis, Cassia tora, Syringa velutina, Zingiber officinale, Malva verticillata, and Panax ginseng C.A. Meyer exhibited inhibitory effects as phytoestrogens in estrogen-responsive human breast cancer cells. This study suggests that some Korean medicinal herbs might be considered as phytoestrogens and be useful to further analyze those plants which contain the estrogenic effect in order to identify the active principles.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.5
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• pp.690-700
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• 2012

The experiment was conducted by in vitro fermentation and bacterial community analysis to investigate the reduction of odorous compounds in response to the use of feed additives (FA) during carbohydrate overload in growing pigs. Soluble starch at 1% (control) and various FA at 0.1% Ginseng meal (FA1); Persimmon leaf (FA2); Gingko nut (FA3) and Oregano lippia (FA4) were added to fecal slurry and incubated anaerobically for 12 and 24 h. In vitro parameters and microbial diversity of the dominant bacteria following fermentation were analyzed using Denaturing Gradient Gel Electrophoresis (DGGE), band cloning and sequencing of the V3 region. Results showed that total gas production increased with the advancement of incubation (p<0.05). pH values of FAs and control groups were decreased except the FA4 group which increased somewhat from 12 to 24 h (p<0.05). Ammonia nitrogen ($NH_3$-N) and $H_2S$ gas concentrations were comparatively lower in both stages in FA4 treatment than in the other groups (p<0.05). Hence, $NH_3$-N concentrations in liquid phases were increased (p<0.05) from 12 to 24 h, but the trend was lowest in FA4 than in the other groups at both stages. The total VFA production was comparatively lower and butyrate levels were moderate in FA4 group than in the the other groups during both stages (p<0.05). Indirect odor-reducing compounds such as $NO_2$, $NO_3$ and $SO_4$ concentrations were higher in the FA4 and FA3 than in the other groups at 24 h (p<0.05). After fermentation, ten dominant bands appeared, six of which appeared in all samples and four in only the FA4 treated group. The total number of DGGE bands and diversity was higher in the FA4-group compared to other groups. Additionally, similarity indices were lowest (71%) in the FA4, which represented a different bacterial community compared with the other groups. These findings indicate that $NH_3$-N, $H_2S$ and VFA production was minimal, and pH was also better in the FA4 group than in the other groups. Furthermore, the conversion of odor-reducing indirect compounds or their intermediates was higher in the FA4 group in compared to the other groups. FA4 group generated less odorous products and more indirect products by in vitro fermentation at 24 h, and their microbial pattern appeared to differ from that of the other groups. These findings suggest that this particular FA could change the microbial population, which may have a beneficial effect on odor reduction. It is recommended that the oregano lippia may be supplied to growing pigs as FA along with excess carbohydrate sources to reduce the production of odorous compounds.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.1
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• pp.8-14
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• 2006

High phosphate accumulations in greenhouse soils have been considered as a new agricultural problem in Korea. The effects of silicate on changes in phosphate fractions and on the yield of Chinese cabbage without P fertilization were investigated by pot experiment. For this experiment, P-accumulated soil was selected (Total-P; $2140mg\;kg^{-1}$). Three levels of silicate (0, 2, and $4Mg\;ha^{-1}$) without P fertilization and P fertilizer without silicate application (Si0+NPK) were applied in 1/2000a pots. The same amount of nitrogen and potassium fertilizers were applied to the all pots. The application of $4Mg\;ha^{-1}$ of silicate greatly increased the yield of Chinese cabbage by 25% compared to Si0+NPK treatment. Although there is no significant difference in plant P absorption among all the treatments, the uptake of P in the $4Mg\;ha^{-1}$ silicate application was significantly higher than Si0+NPK treatment due to increase in yield. The content of available $SiO_2$ in soil increased with increasing silicate application rates. The Si concentration of plant showed a positive correlation with available $SiO_2$ contents in soil and the yield of Chinese cabbage. Total P greatly decreased with increasing rates of silicate application, yet the change in available P content was not significant. The Si0+NPK treatment increased the content of Ca-P by 11%, however, which was decreased by 27% in the $4Mg\;ha^{-1}$ silicate application. Therefore, the effect of silicate on reducing total-P was mainly attributed to the change in concentration of Ca-P. Our results suggest that the application of silicate in P-accumulated soils not only increase the crops yield but also reduces phosphate accumulation.

• Journal of the Korean Society for Marine Environment & Energy
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• v.15 no.4
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• pp.337-348
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• 2012

The Yellow Sea Ecoregion Conservation Project is a joint international project which is carried out under the purposes of conserving the habitats in the Yellow Sea Ecoregion and biodiversity from various threats that damage ecosystems, informing the importance and value of the Yellow Sea Ecoregion, and promoting the understanding and interests of Korea, China and Japan. Subsequent to the Yellow Sea Ecoregion Planning Programme which had been performed during the period from 2002 to 2006, the Yellow Sea Ecoregion Support Project has been performed over 7 years in total from 2007 to 2014. Panasonic is sponsoring the financing of the project, and the organizations in charge of the project by country are Korea Institute of Ocean Science & Technology for Korea and World Wide Fund for Nature branches for China and Japan. While the Yellow Sea Ecoregion Planning Programme was focused on the biological assessment and the selection of potential priority area by scientific review, the Yellow Sea Ecoregion Support Project is oriented toward practical activities targeting more diversified stakeholder. Especially, this project plans to support direct conservation activities in the region and participation and cooperation from local residents. The project plan is comprised of 3 phases. During the first period from 2008 to 2009, small grant projects were operated targeting 16 institutions of Korea and China, and for the second period from 2010 to 2012, one place each was selected as demonstration site for habitat conservation in Korea and China respectively and supported for three years to introduce the conservation method based on international standards such as the management of marine protected areas, ecosystem-based management and community-based management and simultaneously to develop habitat conservation activities suitable for national and regional characteristics. During the period from 2013 to 2014 which is the last phase, the project plans to distribute the performance of small grant projects and demonstration site activities through a series of forums among stakeholder. Through the activities described above, the recognition of general public on the conservation of the Yellow Sea Ecoregion was changed positively, and community-based management began to be reflected in the policies for the marine protected areas of central and local government.