• Korean Journal of Environmental Biology
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• v.36 no.3
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• pp.400-411
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• 2018

This study was a survey of the Wonju stream in Wonju city from May 2015 to September 2016. A total of three sites were selected from the upstream area Gwanseol-dong to the downstream area Hojeo-myeon. Physicochemical analysis, aquatic insect changes, cluster analysis, functional group analysis, rarefaction curve, and statistical analysis were compared between 2004 and 2016. A total of 19 species (38.78%) in 2004 and 22 species (36.67%) in 2016 were analyzed, with the largest number belonging to ephemeroptera. The individual ratio ranged from 27,759.2 (ind. $m^{-2}$, 84.30%) in 2004 to 4,573.2 (ind. $m^{-2}$, 41.64%) in 2016, with the highest number involving diptera. As a result of the community analysis, significant differences were detected in the indices of dominance, diversity, evenness, and richness in 2004 and 2016 (p<0.05). Burrowers of the habitat orientation groups showed the greatest variation with an average of -68.00% (${\pm}2.15$) and the collector-gatherers of the functional feeding groups showed the highest variation of -40.12% (${\pm}1.77$). The rarefaction curve analysis suggested that the species was the poorest in the midstream regions in 2004 and 2016. Physical factors and water quality showed a significant correlation with diversity index, evenness index, and the number of individuals. MDS analysis of the similarity of upstream and downstream regions was high in 2004, and low in 2016. The differences were attributed to physicochemical changes such as increase in flow velocity due to improvement of small dams and changes in bottom structure.

• Journal of Information Management
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• v.42 no.4
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• pp.75-94
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• 2011

The purpose of this study is to analyze the domain on the field of Electrical Engineering in Korea by the author bibliographic coupling analysis. The data set contains a total of 2,157 articles from two core journals with 23,411 citation data from 2005 to 2009 published in two prestigious journals. In order to achieve the purpose of this study, MDS analysis, clustering analysis and network analysis were used to examine core subject areas. In addition, the centrality analysis in the weighted networks was used to explore the key authors in this field such as the top global centrality authors and the top local centrality authors. The findings of this study can be utilized to guide the current research trend and author network for collection development and information services in the field of Electrical Engineering.

• Asia Marketing Journal
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• v.5 no.3
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• pp.35-59
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• 2003

본 연구는 동일 제품범주 내에서 상호 대체가능성(substitutability)을 중심으로 연구 되어 왔던 상표간의 사용상황 대체(substitution-in-use) 이론을 산업간 경쟁의 차원으로 확대하여 적용할 수 있는 가능성을 탐색하는데 그 목적이 있다. 이를 위해 소비자의 소비경험이 선택기준의 중요한 요소로 작용하는 서비스부문을 대상으로 소비자의 선택동기, 즉 소비동기의 차원에서 산업간 경쟁구조와 경쟁강도를 분석하고자 하였다. 연구의 범위는 마케팅 분야에서 비교적 소외되어 왔던 엔터테인먼트 부문, 특히 문화예술부문과 스포츠부문에 초점을 맞추었다. 연구방법으로는 이들간의 심리적 거리를 측정하여, 그 근접성의 정도에 따라 산업간 경쟁구조와 경쟁특성을 분석하였다. 분석도구는 그 동안 마케팅의 영역에서 특정 산업 내에의 상표간 경쟁구조를 연구하는데 이용되었던 심리적 거리측정도구를 이용하였다. 이에 따라 구매자의 사용목적에 따른 상표간 대체 가능성을 산업간의 심리적 근접성을 이용해 측정하고 그 거리의 크기에 따라 경쟁강도의 선택의 대체성을 분석하였다. 방법론적 측면에서는 먼저 엔터테인먼트산업, 문화예술과 공연예술산업, 그리고 스포츠 등의 소비동기 유형을 살펴본 후, 이들 중에서 중복가능성이 있는 동기유형을 선별하였다. 이에 따라 다양한 관람 엔터테인먼트산업에서 나타나고 있는 12개의 소비동기 유 형을 발견할 수 있었다. 이후 이렇게 추출된 동기유형을 대상으로 산업간 대체성을 심적 거리좌표를 이용하여 측정하고 측정된 자료를 다차원척도법(MDS)을 이용해 2차원의 공간 상에 투사하였다. 그리고 상호간의 근접성과 경쟁구조를 확인하고 분석결과에 대해 논의 하였다. 분석결과 엔터테인먼트 상품들간에는 근접성의 차원에서 서로 대체될 수 있음을 발견할 수 있었고 이는 이들이 동일한 시장을 대상으로 경쟁관계가 있음을 시사하는 것이다. 개별 관람동기 차원의 분석 결과, 관람 엔터테인먼트 소비자들은 동일한 관람동기를 서로 다른 많은 유형의 엔터테인먼트산업이나 공연예술, 문화예술상품, 쇼나 오락, 관람스포츠 등에 의해 해결하고 있음을 발견할 수 있었다. 본 연구에서 사용한 접근방법과 연구의 결과는 향후 간접적 관계에서 직접적 관계로 경쟁이 확대되는 많은 마케팅분야에 적용될 수 있을 것이다.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.24 no.1
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• pp.207-228
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• 2013

Due to the advance of scholarly communication, the field of open access has been studied over the last decade. The purpose of this study is to analyze and demonstrate the field of open access via co-word analysis. The data set was collected from Web of Science citation database during the period from January 1998 to July 2012 using the Topic category. A total of 479 journal articles were retrieved and 8,643 noun keywords were extracted from the titles and abstracts. In order to achieve the purpose of this study, network analysis, clustering analysis and multidimensional scaling mapping were used to examine the domain and the sub-domains of open access field. 18 clusters in the network analysis are recognized and 4 clusters are shown in the map of multidimensional scaling. In addition, the centrality analysis in the weighted networks was used to explore the significant keywords in this field. The results of this study are expected to demonstrate and guide the intellectual structure and new approaches of open access field.

• Korean Journal of Ichthyology
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• v.30 no.1
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• pp.36-45
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• 2018

The temporal and depth-related variations in the species composition and abundance of demersal fish assemblage were studied in the coastal waters off Hupo, East Sea. Fish samples were collected seasonally between 2011 and 2017 at two stations of study area using trammel net and bottom gill net. In total, 46 fish species belonging to 17 families were collected during study period, with 36 and 22 species occurring in depths of ~80 m (site A) and ~140 m (site B), respectively. Glyptocephalus stelleri, Cleisthenes pinetorum and Gymnocanthus herzensteini were abundant at shallower site, and Dasycottus setiger at deeper site. The number of species, abundance, biomass and diversity fluctuated with water depth, but not temporally (both seasonally and annually). Analysis of similarity (ANOSIM) revealed that the fish assemblage structures were significantly different with water depth, but not by year or season. Non-metric multidimensional scaling (MDS) ordination plot emphasized visually in spatial difference of fish assemblages, and it was due to differential contributions of dominant species in relation to water depth and temperature.

• Korean Journal of Environmental Biology
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• v.36 no.2
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• pp.140-149
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• 2018

Seasonal variations in the community structure of larval fish assemblage in Jinhae Bay were investigated in February, May, August and November of 2015, and in the same months in 2016. During the study period, a total of 28 larvae species belonging to 24 families were collected. The dominant species were Clupea pallasii, Liparis tanakae, Callionymidae sp., Sillago japonica, Ernogrammus hexagrammus and Engraulis japonica. These six species accounted for 77.6% of the total number of larvae during the survey period. The larvae of C. pallasii and L. tanakae were exclusively caught in February 2015 and 2016, while those of Apogon lineatus and Sillago japonica were exclusively caught in August 2015 and 2016. Overall, species diversity of the fish larvae was highest in February and August, although it was relatively low in May. The results of the non-metric multidimensional scaling (nMDS) analysis using the number of individual larval fish showed that they are divided into four seasonal groups. Our results showed that the community of larval fish in Jinhae Bay was affected by seasonal changes in temperature and the emergence of spawning fish species. Additionally, we suggest that the high abundance of larval fish came from around Jam-do and the northern part of Chilcheon-do; these locations are the main spawning grounds of Jinhae Bay.

• Applied Chemistry for Engineering
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• v.32 no.3
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• pp.320-325
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• 2021

In this study, an optimization for the production of water emulsion was designed by adding an extract of wheat sprout, which is known to contain a large amount of antioxidants. The central composite design of reaction surface analysis method (CCD-RSM) was used for the optimization process. The amount of emulsifier, emulsification time, and added amount of wheat sprout extract were selected as independent variables based on our preliminary experiments. The mean droplet size (MDS), viscosity, and emulsion stability index (ESI) were set as the responses to evaluate the stability of the emulsion. For each independent variable, the P-value and coefficient of determination were evaluated to verify the reliability of the experiments. From the result of CCD-RSM, optimum conditions for the emulsification were determined as 23.6 min, 7.7 wt.%, and 3.9 wt.% for the emulsification time, amount of emulsifier, and amount of sprout, respectively. From the optimized condition obtained, MDS, viscosity, and ESI after 7 days from reaction were estimated as 252.3 nm, 616.7 cP, and 88.7%, respectively. The overall satisfaction was 0.9137, which supported the validity of the experiments, and the error rate was measured at 0.5% or less by advancing the experiments. Therefore, an optimized process for producing an emulsion by adding the malt extract was designed by the CCD-RSM.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.11 no.3
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• pp.97-107
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• 2006

The nektonic assemblages of upper tidal flat area located in the Jangbong Island, near Incheon, were studied using a fence net from March to November 2001. A total of 49 species were recorded, with a mean abundance and biomass of 489 individuals and 5,170.4 g, respectively. The most abundant species by number were Exopalaemon carinicauda(40.9%) and Johnius grypotus(13.2%). By catch weight the dominant species were Acanthogobius hasta(33.7%), Johnius grypotus(14.6%) and Scomberomorus niphonius(10.2%). The conventional multivariate statistics(Cluster analysis and non-metric Multi-Dimensional Scaling) applied to assess temporal variation in nektonic communities. As a result of cluster analysis and MDS ordination, the faunal group could be divided into spring and summer/autumn dominant species group. The spring species included the pisces Acanthogobius luridus, the crab Macrophthalmus japonicus and the gastropods Bullacta exarata and Lunatia gilva. The summer/autumn species were the pisces J. grypotus, Sardinella zunasi, Konosirus punctatus, Chelon haematocheila, S. niphonius and Takifugu niphobles, the shrimp Metapenaeus joyneri and the cephalopod Loligo beka.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.3
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• pp.211-218
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• 2007

In this study, we investigated the spatial distribution of macrozoobenthos in the estuarine sandy flat, the Bongam tidal flat located in Masan Bay during March, 2004. A total 13 species were identified at 12 stations within the tidal flat. The mean density was $20,267\;ind./m^2$, and mean biomass was $228.1g/m^2$. Dominant species in the Bongam tidal flat were all polychaetes: Prionospio japonicus ($11,716\;ind./m^2$, 57.8%) and Polydora ligni ($3,929\;ind./m^2$, 19.4%) of spionoid polychaete, and Neanthes succinea ($3,425\;ind./m^2$, 16.9%) of nereid polychaete. The most dominant species, P. japonicus distributed evenly all stations in the tidal flat. But N. succinea showed high density at the upper area of the tidal flat. Species diversity index (H') was in the range of 0.6 to 1.2 which is relatively low due to the prominent of P. japonicus and few species richness at each station. The study area was divided into two station groups (group A and B) based on the cluster analysis and MDS ordination, and the spatial distribution of macrozoobenthos on the Bongam tidal flat seemed to be in the influence of exposure duration from tidal levels and specific geological topography.

• Journal of the Korean Society for Library and Information Science
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• v.40 no.2
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• pp.333-355
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• 2006

Network generation methods to visualize bibliometric data for examining the intellectual structure of knowledge domains are investigated in some detail. Among the four methods investigated in this study, pathfinder network algorithm is the most effective method in representing local details as well as global intellectual structure. The nearest neighbor graph, although never used in bibliometic analysis, also has some advantages such as its simplicity and clustering ability. The effect of input data preparation process on resulting intellectual structures are examined, and concluded that unlike MDS map with clusters, the network structure could be changed significantly by the differences in data matrix preparation process. The network generation methods investigated in this paper could be alternatives to conventional multivariate analysis methods and could facilitate our research on examining intellectual structure of knowledge domains.