• Ocean and Polar Research
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• 제32권1호
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• pp.1-13
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• 2010

To assess short-term variation of summer phytoplankton community structure in different water masses, phytoplankton and environmental factors were monitored from 31 stations on and off the southern coasts of Korea, from June 18 to June 20 2009. According to multidimensional scaling (MDS) and cluster analysis based on phytoplankton community data from each station, the southern sea was divided into two groups. The first group included stations in the south-eastern region of Jeju Island, which is strongly influenced by the Kuroshio warm current. The second group located along the coastal region of the southern sea, which was mainly comprised of Bacillariophyceae and Crytophyceae. Of these stations, St. 13 and 28 formed a temperature front caused by different hydrological conditions. In particular, nutrients and Chl.a concentrations in these two stations were significantly higher compared to those in the other stations. This indicates that phytoplankton population and subsequent microalgal growth under high nutrient concentrations vary in different water masses. Our results support the theory that phytoplankton community structure in the southern sea of Korea can be influenced on a short-term scale by different water masses and currents.

• 한국어류학회지
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• 제28권2호
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• pp.79-86
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• 2016

본 연구는 동해 남부 연안에서 출현하는 도화망둑 (Amblychaeturichthys hexanema)과 수염문절 (A. sciistius)의 위 내용물을 분석하여 두 어종의 위 내용물 조성을 조사하고, 종 간 그리고 성장에 따른 먹이자원의 분할이 있는지 연구하였다. 도화망둑과 수염문절은 저서성 갑각류를 주로 섭식하는 저서 섭식 육식성어류였다. 저서성 무척추동물과 부유성 먹이 또한 각각 도화망둑과 수염문절의 먹이로써 중요도가 다소 높았다. 중량비 자료를 이용한 non-metric multidimensional scaling (nMDS)와 다변량 분석 (multivariate analyses)에서 두 어종의 위 내용물 조성은 그 차이가 유의하였다. 그러나 두 어종 모두 성장에 따른 위 내용물 조성 변화에서 차이가 유의하지 않았다. 두 어종이 섭식한 먹이생물의 차이는 섭식 행동의 차이와 관련있다. 결론적으로, 본 연구해역에서 두 어종의 위 내용물 분석 결과는 도화망둑과 수염문절 사이에 생태지위 분리의 증거와 먹이 자원에 대한 종 간 경쟁 감소의 가능성을 보여주었다.

• Fisheries and Aquatic Sciences
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• 제10권2호
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• pp.93-101
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• 2007

Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were determined in marine sediments from Mokpo coastal water of Korea. Total and toxic equivalent (TEQ) concentrations of PCDD/Fs ranged from 19.4 to 175pg/g dry weight and ranged from 0.195 to 2.87 pg WHO-TEQ/g dry weight, respectively. These PCDD/F concentrations were below the safety sediment value (20 pg TEQ/g dry weight) of chronic toxicity. A highly significant correlation between the concentrations of PCDD/Fs and total organic carbon (TOC) in marine sediments was observed. Overall PCDD/F concentrations in the sediments were elevated in rivers and at inner locations close to harbors, indicating that these contaminants derived from local discharges of human activities. PCDD/F concentrations measured in our study were lower than those in several industrialized areas in Korea. Nonparametric multidimensional scaling (MDS) ordination showed that combustion processes from industrial complexes are the major source of PCDD/Fs in Mokpo coastal water.

• ALGAE
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• 제23권4호
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• pp.277-288
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• 2008

The relationship between nutrients and phytoplankton dynamics was investigated daily from 12 April to 22 July 2003 in Sagami Bay, Japan. According to multidimensional scaling (MDS) and cluster analysis, phytoplankton community was divided into four distinct groups. The first group was consisted of centric diatom species, such as Guinardia spp., Detonula spp., Letocylindrus danicus, Skeletonema costatum, Eucampia zodiacus and Chaetoceros spp.. The second and third clusters comprised mainly diatoms and dinoflagellates, respectively. The other cluster was restricted to the samples collected during the last sampling period when the rainfall and river discharge was frequently recorded. Canonical correspondence analysis (CCA) was applied to analyze four groups respectively, which focused on the effects of nutrients concentration and ratio on phytoplankton variations. Based on CCA analysis, most species of centric diatom were negatively correlated with DSi concentrations and Si/N ratio. Nutrients were strongly limited phytoplankton growth during the summer when the rainfall was not observed, whereas river discharge by rainfall and counterclockwise coastal currents (although the surface circulation pattern is often altered by Kuroshio Current, the counterclockwise coastal currents are generally dominant) has brought phytoplankton population accumulation and triggered the micoalgae growth in western part of the bay. Phosphorous (P) was strongly limited after significantly increases in the phytoplankton abundances. However, silicate (Si) was not a major limiting factor for phytoplankton production, since Si/DIN and Si/P ratio did not create any potential stoichiometric limitation. This indicates that high Si availability contributes favorably to the maintenance of diatom ecosystems in Sagami Bay.

• 인지과학
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• 제25권1호
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• pp.25-49
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• 2014

본 연구는 한 제품 군(음료)의 다양한 TV 광고들을 대상으로 광고 수용자들이 어떤 속성을 중심으로 광고를 인식하는지 알아보고자 하였다. 이를 위해 다차원척도법을 사용하여, 14개의 음료 광고들의 각 쌍에 대한 광고 수용자의 유사성 평정에 근거한 광고들의 포지셔닝 맵을 도출하였다. 광고 수용자의 인식 구조를 반영하는 포지셔닝 맵의 차원을 알아보고자 각 광고에 대한 주의 요소, 태도, 구매의도에 대한 평정치와 포지셔닝 맵 상의 각 광고 위치 좌표 간의 상관을 조사하였다. 실험 결과, 음료 광고인식 차원은 내용에 대한 주의, 색상, 움직임에 대한 주의 요소와 높은 상관을 보였다. 특히, 주의 요소들 중 내용에 대한 주의가 강조될수록 광고에 대한 감성적, 행동적 태도가 긍정적으로 형성되었으며, 구매 의도도 증가하였다. 이러한 결과는 주의를 끄는 내용이 담긴 광고가 소비자의 긍정적인 태도와 관련이 높음을 시사한다.

• 한국콘텐츠학회논문지
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• 제14권1호
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• pp.386-399
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• 2014

교육 분야에서의 정보시스템 활용도가 높아짐에 따라 교육기관 및 관련기관에서의 개인정보유출 등의 보안사고가 빈번하게 발생하고 있지만, 교육기관의 정보보호 업무자의 현황을 파악하고 이를 체계적으로 관리할 수 있는 교육훈련은 미흡한 실정이다. 본 논문에서는 정보보호 교육의 필요성이 대두되고 있는 국내 교육관련기관 종사자의 기관유형, 근무지역, 담당직무별로 요구되는 정보보호 분야 지식 및 기술에 차이가 있는지를 정보보호 업무자 대상의 설문결과에 대한 다차원척도법(MDS) 분석을 통해 검증하고, 이를 토대로 교육관련기관의 정보보호 교육 프레임워크를 설계하여 제시하였다.

• 동아시아경상학회지
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• 제7권2호
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• pp.21-30
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• 2019

Purpose - In this work, we categorize the 21 shopping items which foreign tourists purchase in South Korea and monitor the level of dissimilarity (or similarity) between each item by utilizing distance matrix, and both hierarchical and k-means cluster analyses, respectively, based on several purpose of visit attributes in 2017. In addition, multidimensional scaling (MDS) method is applied for mining visual appearance of proximities among shopping items based on purpose of visit attributes. Research design and methodology - This study is carried out in 2017 by Ministry of Culture, Sports and Tourism and conduct a face-to-face survey of foreign tourists from 20 countries who purchase shopping items in South Korea. CLUSTER, PROXIMITIES and ALSCAL modules in IBM SPSS 23.0 are used to perform this work. Results - We ascertain that 21 shopping items can be classified into five similar groups which have homogeneous traits by going through two-step cluster analysis. We can position homogeneous places of cluster and shopping items joining each cluster. Conclusions - We can relatively assess patterns and characteristics of each shopping item, come by useful information in activating shopping tour based on the actual state of recognition of foreign tourists and practically apply to each tourism industry on underlying results.

• 정보관리연구
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• 제35권3호
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• pp.125-138
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• 2004

이 연구에서는 현재의 정보검색 환경에서 이용자 친화적인 검색 시스템을 개발하기 위한 한 방안으로 개별문서의 계층적 지식구조 브라우징 인터페이스를 제안하였다. 계층적 형태를 갖는 개별문서의 지식구조를 자동 생성하기 위해 개별문서에 출현한 용어를 이용하여 대군집과 소군집의 용어 클러스터링 결과에 대해 클러스터 대표어 선정 작업을 수행하였고, 이를 대상으로 다차원 척도법을 이용하여 2차원 공간에 개별문서의 지식구조를 표현함으로써 이용자가 개별문서에 대해 보다 용이하게 접근할 수 있는 브라우징 인터페이스를 마련하였다.

• 인터넷정보학회논문지
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• 제20권1호
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• pp.39-46
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• 2019

This paper investigates the importance of various environmental factors that have a strong influence on strawberry yields grown in greenhouse using the pattern recognition methods. The environmental factors influencing the production of strawberries were six factors such as average inside temperature, average inside humidity, average $CO_2$ level, average soil temperature, cumulative solar radiation, and average illumination. The results of analyzing the observed data using Dynamic Time Warping (DTW) showed that the most significant factor influencing the strawberry production was average soil temperature, average inside humidity, and cumulative solar radiation. Second, the results of analyzing the observed data using Multidimensional Scaling (MDS) showed that the most influential factors on the strawberry yields, such as average $CO_2$ level, average inside humidity, and average illumination were differently given for each farms. However, these results are based on the distance in 3D space and can be deduced from the fact that there is not a large difference between these distances. Therefore, in order to increase the harvest of strawberries cultivated in the farms, it is necessary to manage the environmental factors such as thoroughly controlling the humidity and maintaining the concentration of $CO_2$ constantly by ventilation of the greenhouse.

• 수산경영론집
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• 제48권2호
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• pp.53-66
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• 2017

More than 90% of cultured fish is consumed by sliced raw fish which is usually an eating out menu in South Korea. In order to develop the aquaculture industry in Korea, It is very important to know whether consumers can differentiate each species or not and how consumers recognize each species by certain criteria. for example taste, seasonal preference. The purpose of this study is to understand the competitive relationship through positioning studies of each species by the selection attributes. A total of 221 consumers were surveyed in korea. This study adapted multidimensional scaling(MDS) analysis to explore how consumers position sliced raw fish species based on selection attributes. This study has produced perceptual maps of sliced raw fish market. Empirical data was collected from sliced raw fish consumers in Korea. The results of MDS analysis reveal that 7 species are divided into 3 groups(flat fish, black rock fish), (red sea bream, salmon, tuna), (sea bass, gray mullet). In this study flat fish and black rock fish are perceived as safe, familiar, good value species. Red seabream, salmon, tuna are perceived as luxurious species. Sea bass and gray mullet are perceived as unfamiliar species.