• Korean Journal of Ecology and Environment
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• v.52 no.4
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• pp.285-292
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• 2019

Our study was based on the long-term surveys with respect to the major reservoirs located in the Yeongsan and Seomjin river basins. A total of 45 survey sites have been surveyed four times a year from 2008 to 2017. We identified 166 zooplankton species, including 127 rotifers, 26 cladocerans, and 13 copepods. Mean population density and species number of small reservoirs were higher than those of mid and large reservoirs. Considering outliers exceeding the 90th percentile between species occupancy and mean abundance, 10 of 11 habitat generalists were rotifers, and Bosmina longirostris was the only cladoceran. Habitat specialist consisted of three species of rotifers and emerged from one to three survey sites. According to the modularity results, it was found that the survey sites covering the entire river basins were characterized into five groups, which was similar to the classification by maximum water surface areas(MWSA). The result of the eigenvector centrality showed that the size of MWSA had a greater impact on the similarity of zooplankton community structure between reservoirs than the difference in distance between reservoirs. In the case of survey points in near dam or estuary bank of Juam and Youngsan reservoirs, modularity class were separated from other internal survey points of those. Given that the zooplankton interactions may contribute to freshwater functions more than species diversity. These topological features provide new insight into studying zooplankton distribution patterns, their organization and impacts on freshwater-associated function.

• Journal of Distribution Research
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• v.8 no.1
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• pp.91-116
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• 2003

This study empirically analyzes the relationships among small and medium-sized stores' competitive strategies, marketing capabilities, and retail performance to cope with hostile environments like mass merchandisers' threats. To accomplish the proposed research objectives, data were collected from 325 small and medium-sized stores scattered nationwide. Three types of competitive strategies were significantly classified as follows cost leadership, merchandise differentiation, and service differentiation. Also, several strategic groups such as doing-nothing type, service differentiation type, cost leadership type, and merchandiser differentiation type were recognized through the cluster analysis. The test results show that the small and medium-sized stores perceiving hostile environments less importantly marked the high retail performance among clusters like cost leadership type, merchandise differentiation type, and even doing-nothing type. On the other hand, the moderating effects resulted from the interaction between strategic groups and environmental hostility did not have significant influence on retail performance. Additionally, merchandise differentiation cluster obtains and accumulates marketing capability most efficiently and the cluster like cost leadership, service differentiation, and doing-nothing follows next in order. Finally, merchandise differentiation cluster shows the most highest retail performance among the clusters while there was no difference between cost leadership and service differentiation cluster in terms of retail performance.

• Journal of the Korean Geophysical Society
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• v.3 no.3
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• pp.141-152
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• 2000

In the vicinity of the Antarctic-Scotia plate boundary off Elephant Island(EI), geophysical data(multichannel seismic and gravity data) reveal rapid structural variation of the Shackleton Fracture Zone(SFZ) along its strike. The SFZ ridge terminates in front of the Antarctic Peninsula margin, whereas the transform fault of the SFZ continues farther southeast near EI and the width of the SFZ broadens toward the southeast. Accordingly, the SFZ transform fault changes its morphology along its strike as (1) a graben structure along the high Shackleton ridge in Drake Passage, (2) a half-graben structure in oceanic crust just southeast of the Antarctic-Scotia plate boundary, and (3) splay faults deforming the margin of EI. Two phases of tectonic deformation are clearly observed along the transform fault. Major extensional deformation had formed a large-scale half-graben during roughly about $10{\sim}20$ Ma when Drake Passage had opened. And then, the Shackleton fault has been reactivated with reverse sense, which has been caused by recent convergence between Antarctic and Scotia plates due to westward movement of the Scotia plate since 6 Ma.

• The Journal of the Petrological Society of Korea
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• v.14 no.3 s.41
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• pp.157-168
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• 2005

Trachytic rocks among the bimodal metavolcanic rocks of the Gyemyeongsan Formation and adjacent areas are investigated. Some rocks reveal very high content of iron and most rocks show very high abundances of rare earth elements and high field strength elements. Most rocks show significant Eu negative anomaly, which can be interpreted as the result of plagioclase fractionation. Lack of noticeable Nb negative anomaly indicates not-involvement of crustal material in their generation, which excludes the arc environment or remelting of continental crust from their genetic process. Metatrachytes of the Gymyeongsan Formation are plotted within the within-plate environment of the tectonic discrimination diagram utilizing immobile high field strength element Nb and Y. They also show typical characteristics of A-type magma, such as high Ga content. Considering their affinity to Al-type of Eby (1992) and their age of 750 Ma (Lee et al., 1998), they seem to have been produced by the differentiation of mantle-derived within-plate magmatism at the rift, related with the separation of Neoproterozoic supercontinent Rodinia. Possible connection of Gyemyeongsan and Munjuri Formations of the Okcheon metamorphic belt, at least part of them, to the Cathaysia block of South China during the Neoproterozoic is strongly suggested.

• The Journal of the Petrological Society of Korea
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• v.14 no.3 s.41
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• pp.169-179
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• 2005

Acidic metavolcanic rocks distributed around the Chungju iron deposit show significantly high abundances of rare earth elements and high field strength elements. Relatively high ${\epsilon}_{Nd}$(0) values and lack of negative Nb anomaly suggest that assimilation of crustal material is not involved in their generation. They are plotted within the within-plate environment according the tectonic discrimination diagrams. Such geochemical characteristics are very similar to the acidic metavolcanic rocks of Munjuri Formation. They also show geochemical characteristics of Al-type magma of Eby (1992). All such diagnostic characters indicate differentiation of mantle-derived magma produced from the rift environment, related to the breakup of continent. In contrast to the alkali granites and the rare metal deposit both having age of c. 330 Ma, Sm-Nd isotopic data of the acidic metavolcanic rocks do not form well defined isochron. However, the alkali granites reveal low ${\epsilon}_{Nd}$(0) values, while the acidic metavolcanic rocks and the rare metal deposit both have significantly higher ${\epsilon}_{Nd}$(0) values. Considering such differences, we propose following generation hypothesis: The acidic metavolcanic rocks around Chungju iron deposit was erupted at 750 Ma as rest of the acidic metavolcanic rocks of Gyemyeongsan and Munjuri Formations. About 330 Ma ago, partial melting of existing Al-type igneous materials and some old crustal materials produced alkali granite. The rare metal deposit was also produced by redistribution of related materials within the acidic volcanics due to hydrothermal activities occurred at the same time. Sm-Nd isotopic systematics of the acidic metavolcanic rocks were disturbed during the regional metamorphic event at ca. 280 Ma.

• Korean Journal of Ecology and Environment
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• v.55 no.4
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• pp.398-405
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• 2022

The research was based on long-term studies on the major physico-chemical and hydrological factors and zooplankton community dynamics in the Hwang River. We had 341 times survey and collected zooplankton samples in the Hwang River of mid-Nakdong River from 1995 to 2013. We identified 97 zooplankton species, including 77 rotifers, 16 cladocerans, and 4 copepods. The total zooplankton abundance and species diversity were shown distinctive temporal variation (ANOVA, p<0.001). Annual average of zooplankton population density was 58.4±3.2 ind L^-1 (n=341) and the lowest was 17.0±3.8 ind L^-1 (1996, n=20), while the highest was 151.5±32.3 ind L^-1 (2010, n=22). For zooplankton, small rotifer groups(e.g., Keratella sp., Brachionus sp., Trichotria sp.) dominated the study site for 19 years survey. Statistical analysis revealed that there were positive relationships with SiO₂ (p=0.002) and water level (p<0.001) for the high abundance of rotifer community. There were considerable variations both the total cladocerans population and the number of cladocerans' species concerning annual precipitation. Despite the appearance of various zooplankton in the Hwang River, the mean population density remained low. Due to the lateral structures in the Nakdong River, the downstream basin of the Hwang River is inevitably affected. The zooplankton community in our study site is considered to be mainly influenced by external factors that can stably increase and maintain the volume of the water body and internal factors that induce an increase in food sources through the inflow of nutrients into the water body.

• Journal of Digital Convergence
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• v.14 no.10
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• pp.241-252
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• 2016

The purpose of this study is to explain the word-of-mouth communication that evolve differently from traditional marketing communications using existing mass media in an environment of the flooding of new products. In particular, people use digital devices as internet users and various communication is activated in blogs and communities. It is expanding that companies use market maven as a facilitator of communication. The role of Market maven due to the spread of the Internet seems to be more meaningful for marketing activities. Market maven is a look at how it should study moderate effect on word of mouth of new products. Empirical results show that perceived curiosity and perceived innovativeness of new product has a positive impact on the word of mouth of new product, and was confirmed in a moderate effect of market maven.

• The Journal of the Korea Contents Association
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• v.16 no.8
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• pp.540-555
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• 2016

Art in the modern sense takes the lead to reform the society through constant interaction with members in society. Therefore the works of Art should be understood as social compositions that are reconstructed creatively according to the social environmental impact. Recording, collecting and preserving the references are compulsory for the constant social reform, so the importance of Archive is stressed. However, the Art Archive in Korea is operating very limitedly just to provide simple references to the users. Thus, We need to seek for various ways and user-focused service to utilize the digitalized Art culture records, and need positive research on Art Archive to enhance the creative activities. So in this study, we subdivided the interactivity and applied TAM model. Our analysis on the effect on the purpose of use shows that the users need to be provided with useful informations easily for their creative activities. It also shows that the purpose of use increases through awareness of interactivity. However, the result of this study has a limit of the sample so further studies for the purpose is suggested.

• Journal of Global Scholars of Marketing Science
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• v.9
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• pp.189-201
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• 2002

Objectives of this study were: First, the purpose of this study is to develope the factors affecting private brand based on past researches and to review effects of the consumer perception factors affecting private brand preference. Second, to set up research model specifying relationships among price perception, information search and experience, Quality perception and private brand preference. Third, to test hypotheses derived from the research model of this study and to attempts to explain how to have the effect the private brand preference. Marketing implications of this study were: As a result LISREL analysis, price perception, informations search and experience, quality perception increase and enhance private brand preference. Limitations of this study were: Data collection methods used in this study were questionable for the lack of general analysis in the difference of preference between characteristics of purchaser and characteristics of non-purchaser exactly because our sample was only limited to Changwon, Masan and Jinhae. So future study has to include samples in other regions.

• Science of Emotion and Sensibility
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• v.19 no.3
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• pp.71-80
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• 2016

The purpose of this study was to examine the effects of display on time on tasks and virtual presence in the immersive virtual reality. Head mounted display (HMD) and monitor conditions were compared when the participants were asked to complete navigation tasks in a virtual classroom. Time on tasks and virtual presence were measured. Three factors of the virtual presence were applied as dependent variables such as 1) spatial presence, 2) involvement, and 3) realness. The results showed that HMD condition took longer time to finish tasks than monitor conditions. HMD condition showed significantly higher perception from all of the virtual presence factors. Interestingly, there was a significant interaction effect between the display conditions and presence factors. The relationship between display types and virtual presence factors were discussed for future study.