• Title/Summary/Keyword: multidimensional scaling(MDS)

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Annual Variations in Community Structure of Mesozooplankton by Short-term Sampling in Jangmok Harbor of Jinhae Bay (진해만의 장목항에서 단주기 샘플링에 의한 중형동물플랑크톤 군집의 연변동)

  • Hwang, Ok-Myung;Shin, Kyoung-Soon;Baek, Seung-Ho;Lee, Woo-Jin;Kim, Su-Am;Jang, Min-Chul
    • Ocean and Polar Research
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    • v.33 no.3
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    • pp.235-253
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    • 2011
  • The annual variation of mesozooplankton community in the Jangmok harbor of Jinhae Bay was studied in relation to environmental variables. Sampling was carried out weekly from January to December 2009. During the study periods, mesozooplankton community consisted of 44 taxa and the annual mean abundance was 8308 inds. $m^{-3}$. The maximum abundance was observed to be 50043 inds. $m^{-3}$ in August and the minimum in April with 1013 inds. $m^{-3}$. Of these, Penilia avirostris, cirripedia larvae, Evadne tergestina, Acartia omorii, Oikopleura s, Paracalanus parvus s. l., Eurytemora pacifica, Podon s, Oithona s, and Acartia steueri were observed as dominant species in Jangmok bay and they also contributed to 79% of total mesozooplankton. According to non-metric multidimensional scaling (nMDS) and cluster analysis based on the mesozooplankton community data from each season, the community was divided into three groups. The first group included appearence species in winter and spring season, which is mainly dominated the copepod such as A. omorii and E. pacifica. The second and third group was composed with observed species in summer and autumn, respectively. Based on the SIMPER (similarity percentages), P. avirostris in summer and cirripedia larvae in autumn were significantly dominated. Our results indicate that although the mesozooplankton abundances in Jangmok harbor fluctuated abruptly, its annual variation was strongly influenced by water temperature.

Distribution Patterns of Sandy Bottom Macrobenthic Community on the Hupo Coastal Area, in the East Sea of Korea (동해 후포주변 사질조하대에 서식하는 대형저서동물군집의 분포특성)

  • Paik, Sang-Gyu;Kang, Rae-Seon;Jeon, Jae-Ok;Lee, Jae-Hac;Yun, Sung-Gyu
    • Ocean and Polar Research
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    • v.29 no.2
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    • pp.123-134
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    • 2007
  • Distribution patterns of sandy bottom macrobenthic communities were studied around the Hupo coastal area. The seasonal surveys were conducted at 15 chosen sites within a depth range of 10 to 50 m along 10 km of the coastline using a Smith-McIntyre grab $(0.05\;m^2)$ in 2005. Overall depth distribution following the direction of the offshore become deeper parallel to the coastline. A total of 319 macrobenthic species were sampled with a mean density of $1,972\;ind./m^2$, and mean biomass was 82.5 wet-weight $g/m^2$. The major individual-dominant species were three polychaetes Spiophanes bombyx ($436\;ind./m^2$), Scoletoma longifolia ($250\;ind./m^2$) and Magelona japonica ($170\;ind./m^2$), and bivalve Adontorhina subquadrata ($73\;ind./m^2$). Cluster analysis and non-metric multidimensional scaling (nMDS) analysis based on Bray-Curtis similarity identified 2 major station groups which corresponded to macrobenthic faunal assemblages and their characteristic species. In addition, environmental conditions were significantly different between station groups. Group I contained mostly 20 and 50 m deep sites and was associated with sandy mud. Group I was characterized by high abundance of S. bombyx, S. longifolia, A. subquadrata. It was divided into two sub-groups (I-I and I-II) in relation to depth. Sub-group I-I was associated with deeper sites than sub-group I-II. Group II included mostly inshore area shallower than 15 m and was associated with coarse and medium sand. Group II was characterized by Lumbrinerides hayashii and Urothoe grimaldii japonica.

Development and a Psychometric Evaluation of Cardiovascular Disease-Specific Quality of Life Scale for Koreans (한국 심혈관질환 특이형 삶의 질 측정도구 개발 및 평가)

  • Lee, Eun-Hyun;Tahk, Seong-Jai;Shin, Jun-Han;Lee, Young-Whee;Song, Rha-Yun
    • Journal of Korean Academy of Nursing
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    • v.37 no.3
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    • pp.313-323
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    • 2007
  • Purpose: Health-related quality of life (HRQOL) in patients with cardiovascular disease in Korea has rarely been studied, mostly due to the lack of a psychometrically validated disease-specific instrument. The purpose of this study was to develop and validate a cardiovascular specific-HRQOL questionnaire (CD-QOL). Method: The CD-QOL was developed and validated as follows; item generation, pilot study, and psychometric tests. Patients were recruited from three-university hospitals. The patients were asked to complete the preliminary questionnaire comprising the content-validated items, SF-36, and CES-D. The NYHA and KASI classifications were used to classify the functional performance of the patients. The data was analyzed using correlation, factor analysis, multidimensional scaling, multitrait/multi-item matrix, ANOVA, and Cronbach's alpha. Result: Preliminarily, thirty-nine items were generated. Factor analysisextracted a five-factor solution with a total of twenty-two items. One item was deleted based upon the MDS. The remaining items were moderately correlated with the subscales of the SF-36 and associated with depression measured with the CES-D. The mean scores of patients in NYHA and KASI class I were significantly higher than those in NYHA and KASI class II or/and III, which suggested patients with better functional performance were likely to have a better HRQOL. Cronbach's alphas of the total and subscales were all greater than 0.70. Conclusion: The CD-QOL is a easily applicable instrument with excellent psychometric properties of content, criterion, factorial, convergent, and known-groups validity, and internal consistency reliability in Korean patients with cardiovascular disease.

Seasonal Variation of Zooplankton Communities in the Southern Coastal Waters of Korea (남해 연안 동물플랑크톤 군집의 계절변동)

  • Moon, Seong-Yong;Oh, Hyun-Ju;Soh, Ho-Young
    • Ocean and Polar Research
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    • v.32 no.4
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    • pp.411-426
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    • 2010
  • The seasonal variations in the zooplankton community of the southern coastal waters of Korea were investigated seasonally in May, August, November 2005, and February 2006. A total of 74 taxa were sampled, with an average abundance ranging from 2,426~23,793 indiv./$m^3$, among which Noctiluca scintillans predominated. Noctiluca scintillans, Acartia omorii, Acartia erythraea, Paracalanus parvus s. l., Centropages abdominalis, Tortanus forcipatus, and Pseudevadne tergestina were the most abundant species detected. Zooplankton diversity was high around the inner regions during the summer, but it was relatively low in the stations located in the outer regions in the autumn. Non-metric multidimensional scaling (nMDS) revealed significant differences in the structures of the zooplankton community among the three regions. Our results showed that the seasonal variations in zooplankton communities in the southern coastal waters of Korea were attributable to seasonal changes in temperature, salinity, chlorophyll a concentrations, and N. scintillans blooms; additionally, this particularly study area might have been specifically influenced by the appearance of the Tsushima Warm Current.

Effect of geography and altitude on the community characteristics of epigeic spiders in rice field levees (지형 및 고도에 따른 토양성 논거미 군집특성)

  • Eo, Jinu;Kim, Myung-Hyun;Kim, Min-Kyeong;Choi, Soon-Kun
    • Korean Journal of Environmental Biology
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    • v.38 no.4
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    • pp.594-602
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    • 2020
  • This study investigated the effect of geography and altitude on epigeic spider communities in rice field levees in Jeollabuk-do. Spider communities in the mountainous and plain areas were compared to determine the effect of geography on the cultivation periods. The effect of altitude was compared between the Jeongeup and Jangsu areas during non-cultivation periods. Analysis using nMDS (non-metric multidimensional scaling), MRPP (multiple response permutation procedure), and ANOSIM (analysis of similarity) revealed differences in spider community structures between the two types of study areas. Lycosidae predominated at the family level, and its abundance was greater in the mountainous area than in the plains area. The total abundance did not differ between the two areas with different altitudes, but the abundance of three Pardosa species was greater at lower altitudes than at higher altitudes. Geography and altitude had a minimal effect on species richness and diversity indices at the community level. However, several Lycosidae species showed species-specific responses to both geography and altitude in the rice fields.

Spatial and Temporal Distribution and Characteristics of Zooplankton Communities in the Southern Coast of Korea from Spring to Summer Period (봄과 여름철의 남해안 동물플랑크톤 시·공간적 분포와 군집 특성)

  • Moon, Seong Yong;Lee, Mi Hee;Jung, Kyung Mi;Kim, Heeyong;Jung, Jin Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.55 no.2
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    • pp.154-170
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    • 2022
  • The zooplankton composition, abundance, community structure, and species diversity in the major commercial fishery species spawning grounds in the southern coast of Korea were investigated in this study. A total of 80 taxa were sampled, with the mean abundance range of 5,612-11,720 ind. m-3 and the mean biomass range of 41.6-1,086.8 mg m-3. The dominant species were Paracalanus copepodites, Paracalanus parvus s. l., Oithona copepodites, Paracalanus nauplii, Noctiluca scintillans, Oithona similis, and Ditrichocorycaeus affinis. The species diversity indices were highest in August, suggesting that diversity is influenced by neritic and oceanic warm-water species. A cluster analysis with non-metric multidimensional scaling (nMDS) revealed three groups of zooplankton communities. The April and May samples clustered into Group A, having the highest mean total zooplankton abundance and lowest species diversity, consisting mainly of temperate species located in the middle region of the southern coast of Korea. Cluster Group B was from the early summer season (June) and contained the highest species diversity with some oceanic and neritic zooplankton species. Cluster Group C from the summer season (July and August) mainly comprised P. parvus s. l. and O. similis. The redundancy analysis (RDA) indicated that abundance is positively correlated with salinity, and chlorophyll-a concentrations.

Distribution Changes of Freshwater Microalgae Community in the Nakdonggang River, Korea (낙동강 담수 미세조류 군집 분포 변화)

  • Suk Min Yun;Dae Ryul Kwon;Mirye Park;Chang Soo Lee;Sang Deuk Lee
    • Journal of Korean Society on Water Environment
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    • v.39 no.2
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    • pp.181-193
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    • 2023
  • Distribution changes in microalgae communities were studied in the Nakdonggang River at two sampling stations (St.1 Gyeongcheongyo Bridge (GB) and St.2 Daedong Wharf (DW)) at monthly intervals from January 2021 to November 2021. A total of 83 taxa included 82 species, 1 forma, belonging to 49 genera, 32 families, 21 orders, and 8 classes. The most important groups were Bacillariophyta and Chlorophyta. The number of species ranged from 5 to 24 in GB, and from 9 to 21 taxa in DW. The contribution of Bacillariophyta to the total species richness was the highest during all survey periods, and Chlorophyta yielded the next highest value in the study area. The dominant taxa were Aulacoseira ambigua, A. ambigua f. japonica, and Ulnaria acus in this study. Cluster analysis and non-metric multidimensional scaling (nMDS) analysis based on Bray- Curtis similarity identified 4 major groups, which corresponded to microalgae assemblages and their characteristic species. Correlation was analyzed through the CCA analysis. It was found that there was a correlation between the microalgae and environmental factors. It was revealed that the divided groups were distinguished because of the differences by the survey period. Therefore, seasonal change was judged as a major factor affecting the distribution of microalgae communities.

A Study on Coffee Shop Brands Image Positioning by Store Personality Scale (점포개성 척도를 이용한 커피전문점 브랜드 이미지 포지셔닝)

  • Lee, Dong-Han;Lee, Chang-Joo;Lee, Hyung-Keun
    • The Korean Journal of Franchise Management
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    • v.4 no.1
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    • pp.25-53
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    • 2013
  • The coffee shop market in Korea has been rapidly increased in quantitative terms over 10 years since the time when Starbucks opened their first shop in 1999. In recent years, the mature market characteristics that the serious competition of the coffee shop brands make the difference in taste or service reduce has been shown in that market. It's important to build the differentiated brand image for the differentiation of products and services and obtaining a price premium in serious competitive mature market. This study presented practical implications based on the results of empirical analysis of current positioning using 'Store Personality Scale.

A Study on Brand Positioning of Franchise Snack Bar - Focused on Busan Area - (프랜차이즈 분식점의 브랜드 포지셔닝에 관한 연구 - 부산 지역 대학생을 중심으로 -)

  • Lee, Soon-A;Kang, Hee-Seog;Lee, Sang-Mook
    • Culinary science and hospitality research
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    • v.23 no.2
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    • pp.11-22
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    • 2017
  • This study is focused on five franchise snack bars to create an effective marketing strategy by analyzing the competitive relationships among them and by grasping selection properties that satisfy customers. Discriminant Analysis was utilized to suggest methodological frameworks, and the results show three factors (food quality, employees' service, and physical environment) were extracted that contains twenty five questions. A one-way analysis of variance (ANOVA) was carried out in order to verify if there were statistically meaningful differences in the Franchise snack bars, and post hoc comparisons were conducted using the Duncan method. In addition, Multidimensional Scaling (MDS) was used to measure brand similarity, selection attributes, and brand preferences. The results of the analysis show that Addal had the highest scores on average in all three factors (food quality, employees' service, and physical environment), Bong-Gus Babberger had two higher scored factors (employees' service and physical environment) than the average, and Gobongmin kimbab had also two higher scored factors (food quality and physical environment) than the average. Kimbab chunguk appeared to have lower scores than the average in all three factors (food quality, employees's service, and physical environment). The findings of this study provide a useful positioning map of competitiveness among five brands and offer practical marketing proposals.

Seasonal Variation of Larval Fish Community in Jinhae Bay, Korea (진해만 자어 군집의 계절 변동)

  • Moon, Seong Yong;Lee, Jeong-Hoon;Choi, Jung-Hwa;Ji, Hwan Sung;Yoo, Joon-Taek;Kim, Jung-Nyun;Im, Yang Jae
    • 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.