• Title/Summary/Keyword: ClusterAnalysis

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Emotional adjective profiles of various odor stimuli (감성형용사를 사용한 다양한 향의 프로파일)

  • Jung, Yun-Jin;Lee, Guk-Hee;Li, Hyung-Chul O.;Kim, Shin-Woo
    • Science of Emotion and Sensibility
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    • v.18 no.2
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    • pp.75-84
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    • 2015
  • Although various methods have been proposed and utilized for video reality improvement, use of olfaction still remains at a rudimentary stage. Previous research reported reality improvement effect of some scents when a video displayed specific objects whose odors matched to the scents provided. In addition, another study showed that provision of scents that correspond to the prevailing color of a video improves sense of immersion. However, the above studies have clear limitations because not all videos have specific odor or obvious color. Assuming, in this study, that sensibility-based scent provision in the absence of main odor or color will increase sense of reality, the present study aimed at building adjective profiles of various scents that convey different sensibilities. To this end, in Experiments 1 and 2, we collected a set of adjectives appropriate for description of scents, and in Experiment 3, we built profiles of 16 scents using 30 adjectives. In addition, we grouped scents of similar sensibilities using cluster analysis. These results could be used not only for video reality improvement but also for the purposes of emphasizing product concepts or store positioning, etc.

Benthic Polychaetous Community in Northern Kyeonggi Bay in December 1995 (1995년 12월 경기만 북부해역에서와 저서다모류 군집)

  • Shin, H.C.;Koh, C.H.
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.3 no.4
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    • pp.261-270
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    • 1998
  • This study was carried out in order to investigate the distribution and species composition of benthic polychaetous community in northern Kyeonggi Bay in September 1995. Mean density of benthic animals was 557 indiv./$m^2$. Benthic polychaetes were the most dominant faunal group, comprising 60 species with a mean density of 488 indiv./$m^2$. Benthic polychaetes were most abundant in Yumha Channel centering on Incheon Harbor, whereas relatively poor in the intertidal zones fringing Yongjong Island and Songdo area, and in the offshore main channel. The most dominant polychaete was Heteromastus filiformis (47.3% of polychaetous community), followed by Nephtys palybranchia, Tharyx sp., Sternaspis scutata and so on. Kyeonggi Bay could be divided into 4 regions from cluster analysis based on the dominant species composition: offsea/channel region, Incheon Harbor, intertidal zone of Yongjong Island, and intertidal zone of Songdo area. Highest species number and diversity index (H') were recorded at offsea/channel region, whereas highest faunal density at Incheon Harbor. Incheon Harbor was characterized by high abundance of H. filiformis. Compared with the previous studies carried out in Kyeonggi Bay, faunal density and species number have little changed for the recent 10 years. Dominant species was different between each study, but has been among opportunistic species of small-sized polychaetes belonging to capitellids, cirratulids or spionids. These results indicate that Kyeonggi Bay has been organically polluted steadily; specifically, this study reveals that Incheon Harbor has been the center of pollution and that the benthic community in the outer sea off Sihwa dike has become unstable.

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Construction of DNA Profile Data Base of Strawberry Cultivars Using Microsatellite Markers (Microsatellite 마커를 이용한 딸기 품종의 DNA Profile Database 구축)

  • Hong, Jee-Hwa;Choi, Keun-Jin;Kwon, Yong-Sham
    • Horticultural Science & Technology
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    • v.32 no.6
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    • pp.853-863
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    • 2014
  • This study was carried out to construct a DNA profile database of 100 strawberry cultivars using microsatellite markers. Two hundred seventy four microsatellite primer pairs were screened with a set of 21 strawberry cultivars with different morphological traits. Twenty five primer pairs were selected because they produced reliable and reproducible fingerprints. These primer pairs were used to develop DNA profiles of 100 strawberry cultivars. Three to thirteen alleles were detected by each marker with an average of 7.50. The average polymorphism information content varied from 0.331 to 841 (average 0.706). Cluster analysis showed that the 100 cultivars were divided into 7 major groups reflecting geographic origin and pedigree information. Moreover, most of the cultivars could be discriminated by marker genotypes. These markers will be useful as a tool for the protection of plant breeders' intellectual property rights in addition to providing the means to intervene seed disputes relating to variety authentication.

Spatial Distribution of Epilithic Diatom Communities in the Estuary of Korean Peninsula (한반도 하구역 부착돌말류의 공간적 분포)

  • Kim, Ha-Kyung;Cho, In-Hwan;Kim, Young-Hyo;Lee, Min-Hyuk;Kim, Yong-Jae;Won, Du-Hee;Hwang, Su-Ok;Byun, Jung-Hwan;Hwang, Soon-Jin;Kim, Baik-Ho
    • Korean Journal of Ecology and Environment
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    • v.51 no.1
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    • pp.1-15
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    • 2018
  • With land-use (cover) and water quality, the distributional characteristics of epilithic diatom communities were studied with 193 samples from estuaries of Korean peninsula between 2015 and 2016. Of total 394 taxa classified, Nitzschia perminuta (19.6%) and N. inconspicua (14.0%) were the 1st and 2nd dominant species. Using a cluster analysis, the epilithic diatom communities of Korean estuaries were divided into four groups (G1-G4). Ecological characteristics of each group were followed: G1 was located in estuaries of the East Sea, and characterized by high forest land-use and high DO and low nutrients; G2 was the eastern part of the South Sea, and characterized by low turbidity and nutrients; G3 was the western part of the South Sea, and characterized by high agriculture, low electric conductivity and low salinity; G4 was the Yellow Sea, and characterized by high nutrients. The environmental factors having significant correlation with diatom distributions were as follows: TN to G1, turbidity to G2, agriculture to G3, and TP to G4. Moreover, the important factors affecting the occurrence of indicator species were forest land-use for Fragilaria construens var. venter in G1, turbidity for Rhoicosphenia abbreviata in G2, urban land- use and total phosphorus (TP) for Bacillaria paradoxa and Hantzschia amphioxys of G3, and TP and turbidity for N. ovalis and Stephanodiscus invistatus of G4. These results collectively indicate that the distribution of epilithic diatom communities in Korean peninsula was largely effected by water quality and land cover/use.

Changes in Community Structure of Chironomidae Caused by Variability of Environmental Factors among Weir Sections in Korean Rivers (국내 보구간의 환경요인 차이에 의한 깔따구의 군집 구성 변화)

  • Kim, Won-Seok;Park, Jae-Won;Hong, Cheol;Choi, Bohyung;Kim, Ho-Joon;Park, YeonJeong;Park, Jung-Ho;Song, Haeng-Seop;Kwak, Ihn-Sil
    • Korean Journal of Ecology and Environment
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    • v.53 no.1
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    • pp.46-54
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    • 2020
  • Artificial and natural changes such as weir construction and climate change often cause abnormal blooming of organism. Therefore, variations in species community of organisms have been actively investigated to identify influential environmental changes on the fresh water ecosystem. In this study, we investigated Chironomidae community and environmental factors at 5 representative weirs (Ipo, IP; Sejong, SJ; Juksan, JS; Gangjeong-goryung, GG; and Dalsung weir) in 4 Korean major rivers to figure out relationship between Chironomidae community and environmental factors. Environmental factors indicating organic matter (total organic carbon, TOC and Chlorophyll-a, Chl-a) showed lower concentration in IP and SJ compared with other sites(JS, GG and DS). 3 sub-family 18 genus 25 species of Chironomidae community were found in this study. Among them, Chironominae was dominant in JS (Tanytarsus sp.1), GG (Polypedilum scalaenum) and DS (Polypedilum scalaenum), while different sub-family were dominant in IP (Orthcladinae, Tokunagayusurika akamushi) and SJ (Tanypodinae, Tanypus punctipennis). Moreover, based on the dominant species of Chironomidae community and environmental factors, the cluster analysis classified our study sites into 3 groups. These results imply that the diet resource is the most important factor for dominance of Chironomidae in Korean rivers. We also suggest that further study on the identification of diet resources for each Chironomidae specie is required for better understating of distribution in species community of Chironomidae at various ecosystems.

Exploring the Class Observation and Nomination System for the Identification of Gifted Students Using a Concept Mapping Approach (영재교사들이 지각하는 관찰-추천 영재판별 시스템의 방향, 중요도, 실행수준 분석: 개념도 연구법을 활용하여)

  • Han, Ki-Soon;Lee, Jeong-Yong
    • Journal of Gifted/Talented Education
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    • v.21 no.1
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    • pp.107-122
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    • 2011
  • The purpose of this study is to explore the perception of the observation and nomination system for the identification of the gifted and to find out the importance and practice level perceived by the gifted education teachers using the concept mapping approach. For this, twelve gifted education teachers brainstormed and gathered ideas for the ideal ways of observation and nomination system and the gathered statements were solicited. Multidimensional scaling and hierarchical cluster analysis were also used. In addition, 112 gifted education teachers rated the importance of and the practice level for the suggested ideas of observation and nomination system. Results were as follows: First, 36 statements were solicited and as a result of concept mapping the suggested observation and nomination system were categorized as 'attainment of professionality', 'attainment of administrative support', 'attainment of fairness', and 'considering points for recommendation.' Second, there were significant differences between the perceived importance levels and the practice levels. Based on the results, imlications of the study were discussed in depth.

Spatial Distribution of Benthic Macrofaunal Community in Ulsan Bay and Onsan Bay, Eastern Coast of Korea (울산만과 온산만 저서동물군집의 공간분포)

  • Yoon, Seong-Myeoung;Koh, Chul-Hwan;Shin, Hyun-Chool
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.6 no.3
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    • pp.180-189
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    • 2001
  • This study was conducted to investigate the macrobenthic community in Ulsan Bay and Onsan Bay, in November of 1997. The density of benthic animals was 535 md./m2, and the number of species was 117. Polychaeta was the most dominant faunal group, comprising a total of 63 species, and its density was 380 md./m2 The most dominant benthic macrofauna was Cirratulrus cirratulas (2.7%), and followed by Tharyx sp. (16.6%), Ruditapes philippinarum (16.1%), Lumbrineris longifolia (10.3%) and so on. The dominant species occupied their distinct unique distribution area. Tharyx sp., R. philippinarum and Grandidierella sp.1 occurred mainly in Ulsan Bay, L. longifolia and Euchone sp. in Onsan Bay, and C. cirratulas and Cirriforimia tentaculata in both bays. By cluster analysis, study area was divided into 4 station groups: Northern Ulsan Bay (Al), the middle area of Ulsan Bay (Bl), offsea area between Ulsan Bay and Onsan Bay (Bll), and Onsan Bay (C). Northern Ulsan Bay was characterized by low species number and high density. The dominant species were C. cirratulas R. philippinarum and Tharyx sp. The middle area of Ulsan Bay was by low species number and density, and its characteristic species was Grandidierella sp.1. The offsea area between Ulsan and Onsan Bay was by high species number and low density. Onsan Bay was by high species number and high density, and its important species were L. longifolia and Euchone sp.

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Spatio-temporal Distributions of Macrobenthic Community on Subtidal Area around Mokpo, Korea (목포 주변 해역 조하대 저서동물 군집의 시 ${\cdot}$ 공간적 분포)

  • Lee, Jae-Hac;Choi, Jin-Woo;Park, Heung-Sik
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.5 no.2
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    • pp.169-176
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    • 2000
  • This study was carried out to clarify the spatial and temporal patterns of macrobenthic assemblages on the subtidal area around Mokpo, southwest of Korea. A total of 238 species and 663 ind./$m^{2}$ were collected. Polychaetes were the most abundant faunal group that comprised 88 species and had a mean density of 389 ind./$m^{2}$. In the semi-enclosed Youngsan River estuarine bay and neighbouring Mokpo Port area were composed of fine sediments with high organic content, and revealed large seasonal variations in the salinity of surface water and bottom dissolved oxygen in contrast to little seasonal changes in those parameters in the outer area. The study area was classified into four station groups by the cluster analysis; the harbor area, the offshore area, and the inner and outer estuarine bay. Two estuarine bay areas showed different species composition; the dominant species of inner bay were Tharyx sp., Poecilochaetus johnsoni, Heteromastus filiformis and other opportunistic species whereas those in the outer bay were Ruditapes philippinarum, Corophium sinense. From the environmental data and species composition of benthic community, the inner bay was characterized to have unstable benthic faunal assemblages, especially under the seasonal disturbance and receiving large amount of organic matter input and intermittant discharge of fresh water. The coastal developments around Mokpo city also seem to have stressed the subtidal communities spatio-temporally.

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Macrobenthic Community of the Subtidal Soft Bottom of Aenggang Bay in the Southern Coast of Korea (남해 앵강만 조하대 연성저질 저서동물 군집)

  • Lim, Hyun-Sig;Park, Heung-Sik;Choi, Jin-Woo;Je, Jong-Geel
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.4 no.1
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    • pp.80-92
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    • 1999
  • This study was conducted to describe the community structure of macrobenthos in Aenggang Bay, the southern coast of Korea. Sampling was performed seasonally using van Veen grab from October 1994 to August 1995. A total of 233 species occurred; polychaetes accounted for 90 species, crustaceans 66 species, and mollusks 46 species. The mean density of macrobenthos was 1,358 ind./$m^2$, and polychaetes accounted for 64% of total abundance with its density of 874 ind./$m^2$. Mean macrobenthic biomass was 261.96 gWWt/$m^2$, and echinoderms accounted for 52.6% of total biomass with its biomass of 137.76 gWWt/$m^2$. Dominant species were a serpulid worm, Ditrupa arientina (245 ind./$m^2$), a cirratulid worm, Tharyx sp. (166 ind./$m^2$), and a scaphopod Fustaria nipponica (132 ind./$m^2$). Ditrupa arientina and Fustaria nipponica were distributed mainly in the mouth of Aenggang Bay, whereas Tharyx sp. showed its high density in the central region of the bay. The study area showed a regional difference in species richness, abundance, and biomass; the eastern region of the bay sustained relatively more abundant and richer macrobenthos than the western part. The study area could be divided into 5 regions by the cluster analysis based on the species composition of macrobenthos; the inner bay, two central regions, and two mouth areas of the bay.

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Distribution Patterns of the Benthic Macrofaunal Community in the Coastal Area of Inchon, Korea (인천연안역 저서동물군집의 시.공간적 분포 양상)

  • Koh, Byoung-Seol;Lee, Jae-Hac;Hong, Jae-Sang
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.2 no.1
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    • pp.31-41
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    • 1997
  • This study was carried out to investigate the composition and the distribution of the benthic community in the coastal area of Inchon seasonally from May 1994 to February 1995, and to estimate the environmental factors that effect the temporal and the spatial changes of benthic species composition. In the present study, 231 species were collected with the average density of 455 ind./$m^2$. The dominant species were Heteromastus sp., Sternaspis scutata, Chaetozone setosa, Mediomastus sp., Glycinde sp., Glycera sp. and Nephtys oligobranchia, which are in the polychaete group; abundance of these species showed seasonal and spatial variations. The study area was divided into 4 regions by cluster analysis such as outside area of Palmido (I), main channel region and adjacent are of Shihwa sea wall (II), north-eastern area of Youngjongdo (III), and the Inchon harbor and the mouth area of Sorae harbor (IV). The particle size of sediment which generally influences the distribution of the benthic community, the differences of the concentration of heavy metals, and of the dissolved oxygen, the increase of the proportion of polychaetes and molluscs, the absence of the crustacean phoxocephalids, and the increase of the abundance of pollution indicator species, indicated that the environment of the areas have been degrading gradually from Group I to Group IV.

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