• Title/Summary/Keyword: the principal component analysis

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Seasonal and Spatial Distribution of Soft-bottom Polychaetesin Jinju Bay of the Southern Coast of Korea (진주만에서 저서 다모류의 시 · 공간 분포)

  • Kang Chang Keun;Baik Myung Sun;Kim Jeong Bae;Lee Pil Yong
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.35 no.1
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    • pp.35-45
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    • 2002
  • Seasonal quantitative van Veen grab sampling was conducted to characterize the composition and structure of the benthic polychaete community inhabiting the shellfish farming ground of a coastal bay system of Jiniu Bay (Korea). A total of 132 polychaete species were identified and the polychaetes accounted for about $80\%$ of overall abundance of benthic animals. There was little significant seasonal difference in densities (abundances) of polychaetes, Maximum biomass was obseued in summer (August) and minimum value was recorded in winter (February) and spring (May). Conversely, diversity and richness were lowest in summer, indicating a seasonal variability in the polychaetous community structure, The cluster analysis indicated that such a seasonal variability resulted mainly from the appearance of a few small, r-selected opportunists in spring and the tubiculous species of the family Maldanidae in summer. On the other hand, several indicator species for the organically enriched environments such as Capitelia capitata, Notoniashs Jatericeus and hmbrineris sp. showed high densities during all the study period. Density and biomass of univariate measures of community structure were significantly lower in the arkshell-farming ground of the southern area than in the non-farming sites of the bay, A similar general tendency was also found in the spatial distributions of species diversity and richness. Principal component analysis revealed the existence of different groups of benthic assemblages between the arkshell-farming ground and non-farming sites, The lack of colonization of r-selected opportunists and/or tubiculous species in the former ground seemed to contribute to the spatial differences in the composition and structure of the polychaetous communities. Although finer granulometric composition and high sulfide concentration in sediments of the arkshell-farming ground and low salinity in the northern area were likely to account for parts of the differences, other environmental variables observed were unlikely. The spatial distribution of polychaetes in Jiniu Bay may be rather closely related to the sedimentary disturbance by selection of shells for harvesting in spring.

A Study on the Marine Biological and Chemical Environments in Yeosu Expo Site, Korea (여수 엑스포 해역의 생물.화학적 해양환경 특성)

  • Noh, Il-Hyeon;Oh, Seok-Jin;Park, Jong-Sick;An, Yeong-Kyu;Yoon, Yang-Ho
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.13 no.1
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    • pp.1-11
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    • 2010
  • In order to understand the biological environmental characteristics with temporal variations of the physico-chemical factors in 2012 Yeosu Expo site of Korea, we investigated at one station, once per week, from April 2006 to December 2007. The surface water temperature ranged from 6.8 to $27.8^{\circ}C$ and the bottom water temperature ranged from 6.3 to 25.9 $25.9^{\circ}C$. The salinity varied from 12.8 to 33.0 psu in the surface water and from 25.2 to 33.6 psu in the bottom water. A strong halocline was observed between the surface and bottom layers in the summer when a rapid decrease of salinity coincided with heavy rainfall. The DIN concentration ranged from 1.36 to $82.7{\mu}M$ in the surface water and from 0.82 to $25.2{\mu}M$ in the bottom water. Phosphate concentration varied from 0.06 to $2.13{\mu}M$ in the surface water and from 0.07 to $1.38{\mu}M$ in the bottom water. Silicate was $1.68-52.0{\mu}M$ in the surface water and $1.37-30.7{\mu}M$ in the bottom water. The nutrient concentrations were generally high during heavy rainfalls and low water temperature periods, and considerably decreased in spring and autumn. The N/P ratio ranged from 4.43 to 325 in the surface water and from 3.8 to 321 in the bottom water. It increased rapidly during the heavy rainfall season and remained at a value of approximately 16 in other periods. The chlorophyll a concentration ranged from 0.46 to $65.0{\mu}g$ $L^{-1}$ in the surface water and from 0.71 to $15.0{\mu}g$ $L^{-1}$ in the bottom water. $Chl-{\alpha}$ concentration remained low in periods of low water temperature, however rapidly increased in periods of high water temperature. From the results of principal component analysis (PCA) and multiple regression analysis (MRA), we conclude that temporal variations of physico-chemical and biological factors were greatly affected by the influx of fresh water, and that nutrients were well controlled by their uptake and assimilation by phytoplankton. Also, during the low water temperature periods, environmental structure in this study site was affected by recycled nutrients through nutrient cycling and mineralization.

Development of the Korean Version of the Brief Measure of Worry Severity(BMWS) (한국어판 간이걱정척도의 개발)

  • Lim, Jae-Hyoung;Joe, Sook-Haeng;Han, Chang-Su;Kim, Seung-Hyun;Yang, Jae-Won;Lee, Moon-Soo;Jeong, Hyun-Ghang;Ko, Young-Hoon
    • Korean Journal of Psychosomatic Medicine
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    • v.19 no.2
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    • pp.92-100
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    • 2011
  • Objectives:We developed a Korean version of the Brief Measure of Worry Severity(BMWS), and examined its reliability, validity, and factor structures. We also explored the associations of pathological worry with depression and anxiety. Methods:Three hundreds fifty-two subjects including community population and college students completed the BMWS, and 27 subjects repeated the scale three weeks later. Reliability was assessed by Cronbach's coefficient ${\alpha}$ and test-retest correlation. The external validity was examined by the correlation of the BMWS score with the scores of Beck Depression Inventory(BDI), Patient Health questionnaire-2(PHQ-2), State Anxiety Inven-tory(SAI), and Trait Anxiety Inventory(TAI). And principal component analysis was performed to evaluate the construct validity. The associations of pathological worry with depression and anxiety were explored using partial correlation analysis. Results:Cronbach's coefficient ${\alpha}$ for the BMWS was 0.904 and test-retest correlation was 0.56(P<0.01). The Spearman correlation coefficients of the BMWS score with the scores of BDI, PHQ-2, SAI, and TAI were 0.60(P<0.01), 0.42(P<0.01), 0.36(P<0.01), and 0.59(P<0.01), respectively. The BMWS showed unifactorial construct. When controlling for TAI score, the correlation coefficient between the BMWS score and the BDI score was 0.357(P<0.01), and when controlling for BDI score the correlation coefficient between the BMWS score and the TAI score was 0.446(P<0.01). Conclusion:The Korean version of the BMWS was found to be a reliable and valid questionnaire for measuring pathological worry. And we could identify the associations of the pathological worry with depression as well as anxiety.

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Characteristics on spatial distributions of phytoplankton communities in relation to water masses in the western South Sea, Korea in early autumn 2021 (2021년 이른 가을 남해 서부 해역의 수괴 분포 및 식물플랑크톤 군집의 공간분포 특성)

  • Yang Ho Yoon
    • Korean Journal of Environmental Biology
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    • v.39 no.4
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    • pp.559-572
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    • 2021
  • A survey was conducted to analyze water masses and spatial distributions of phytoplankton communities at 15 stations on the surface and chlorophyll a maximum layers (CML) in the western South Sea of Korea from September 8 to 9, 2021. As a result, water masses were classified into Coastal Waters (CW) with relatively low salinity, the Tsushima Warm Current (TWC) with high water temperature and high salinity, and mixed waters (MW) showing a mixture of these two water masses. Turbidity showed high concentration in both the surface and CML. The chlorophyll a concentration was as low as 0.90±0.43 ㎍ L-1 in the surface, more than 1.1 ㎍ L-1 in CW, around 1.0 ㎍ L-1 in MW, and less than 0.5 ㎍ L-1 in the TWC. CML was 1.64±0.54 ㎍ L-1. Regarding species composition of phytoplankton communities, there were 57 species in 31 genera(diatoms, 57.8%; dinoflagellates, 35.1%; and other phytoflagellates, 7.1%). The phytoplankton standing crop had 4.6±7.6 cells mL-1 in the surface, more than 30 cells mL-1 in the CW, 2-5 cells mL-1 in the MW, and less than 2 cells mL-1 in the TWC. CML was slightly higher than the surface with a variation of 5.7±8.4 cells mL-1. Dominant species were found to be Rhizosolenia flagilissima f. flagilissima, Skeletonema costatum-ls, and Nitzschia sp./ small size in the surface. For the CML Rh. flagilisima f. flagilissima showed a dominance of 12.0%. For the surface, the diversity variation was 2.36±0.40, which was high for TWC but low for MW. For CML, the diversity variation was 2.29±0.52, which was slightly lower than that of the surface. The dominance in the surface was 0.50±0.15, with a fluctuation range of more than 0.5 in MW and less than 0.5 in the TWC, which was different from the diversity. According to correlation analysis and principal component analysis (PCA), the presence of phytoplankton standing crops was high in CW but low in MW and TWC. That is, phytoplankton communities in early autumn were strongly affected by the expansion and mixing of water masses in western South Sea.

The Validation Study of Beck Depression Scale 2 in Korean Version (한국판 벡 우울 척도 2판의 타당화 연구)

  • Lim, Sun-Young;Lee, Eun-Jeong;Jeong, Seong-Won;Kim, Hee-Chul;Jeong, Cheol-Ho;Jeon, Tae-Yeon;Yi, Min-Soo;Kim, Jae-Min;Jo, Hyeon-Ju;Kim, Jeong-Beom
    • Anxiety and mood
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    • v.7 no.1
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    • pp.48-53
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    • 2011
  • Objective : Korean Version of Beck-II Depression Inventory to verify the reliability and validity of the proposed standards are practical and standardized, cut-off score by establishing a baseline indicating the presence of depression and depression On in the evaluation was to evaluate the clinical usefulness. Methods : 739 patients with major depression using the SCID and normal controls were 302 study subjects. Of patients with clinically significant medical condition, or psychotic disorders, organic mental disorder, epilepsy or seizure disorder, eating disorders are associated with patients taking anti-convulsants experienced in the past, patients were excluded from the study. Results : The main findings of this study were as follows. First, with respect to the KBDI-II items, the correlation between them ranged from 0.51 to 0.74, and was 0.60 over all questions. Further, the overall correlation of the KBDI-II plates showing confidence 'normal' than it was verified that. Second, the BDIII was used in each group to examine internal consistency and thus, whether Cronbach's alpha values were greater than 0.94. Third, the principal component analysis sought to extract factors in a way consistent with the results inspected last 3 factors were extracted and the total variance explained was 47.3%. Fourth, the Cutting calculated the score on the KBDI-II for ROC (Receiver operator characteristic) analysis yielding 18 dot, with the highest sensitivity and specificity was seen. Conclusion : Based on the results of this Study, the KBDI-II cut-off point should be valid as prescribed in 18 is considered.

Eco-environmental assessment in the Sembilan Archipelago, Indonesia: its relation to the abundance of humphead wrasse and coral reef fish composition

  • Amran Ronny Syam;Mujiyanto;Arip Rahman;Imam Taukhid;Masayu Rahmia Anwar Putri;Andri Warsa;Lismining Pujiyani Astuti;Sri Endah Purnamaningtyas;Didik Wahju Hendro Tjahjo;Yosmaniar;Umi Chodrijah;Dini Purbani;Adriani Sri Nastiti;Ngurah Nyoman Wiadnyana;Krismono;Sri Turni Hartati;Mahiswara;Safar Dody;Murdinah;Husnah;Ulung Jantama Wisha
    • Fisheries and Aquatic Sciences
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    • v.26 no.12
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    • pp.738-751
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    • 2023
  • The Sembilan Archipelago is famous for its great biodiversity, in which the humphead wrasse (Cheilinus undulatus) (locally named Napoleon fish) is the primary commodity (economically important), and currently, the environmental degradation occurs due to anthropogenic activities. This study aimed to examine the eco-environmental parameters and assess their influence on the abundance of humphead wrasse and other coral reef fish compositions in the Sembilan Archipelago. Direct field monitoring was performed using a visual census throughout an approximately one km transect. Coral cover data collection and assessment were also carried out. A coastal water quality index (CWQI) was used to assess the water quality status. Furthermore, statistical-based analyses [hierarchical clustering, Pearson's correlation, principal component analysis (PCA), and canonical correspondence analysis (CCA)] were performed to examine the correlation between eco-environmental parameters. The Napoleon fish was only found at stations 1 and 2, with a density of about 3.8 Ind/ha, aligning with the dominant composition of the family Serranidae (covering more than 15% of the total community) and coinciding with the higher coral mortality and lower reef fish abundance. The coral reef conditions were generally ideal for supporting marine life, with a living coral percentage of about > 50% in all stations. Based on CWQI, the study area is categorized as good and excellent water quality. Of the 60 parameter values examined, the phytoplankton abundance, Napoleon fish, and temperature are highly correlated, with a correlation coefficient value greater than 0.7, and statistically significant (F < 0.05). Although the adaptation of reef fish to water quality parameters varies greatly, the most influential parameters in shaping their composition in the study area are living corals, nitrites, ammonia, larval abundance, and temperature.

Quality Characteristics and Consumer Acceptability of Brownies with Rice Bran Dietary Fiber (현미 식이섬유를 대체한 브라우니의 품질 및 관능적 특성)

  • Yeom, Kyung Hun;Kim, Ji Hyun;Lee, Jee Hyun;Bae, In Hyu;Chun, Soon Sil
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.12
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    • pp.1823-1829
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    • 2016
  • This study investigated the optimal percentage of brownies substituted with rice bran dietary fiber (3%, 6%, 9%, and 12%). The sample and control were compared for quality characteristics, specific gravity, viscosity, pH, moisture content, water activity, specific volume, color, textural characteristic, consumer acceptance, and CATA (check-all-that-apply). The specific gravity of the control sample was not significantly different among the samples. The viscosity was highest at the brownie containing 12% of rice bran dietary fiber. Moisture content and water activity were highest in the 6% sample. pH of control sample batter was highest, but reduced with increasing amounts of rice bran dietary fiber. For colors, lightness of the 6% sample batter was highest at 25.31, and redness and yellowness significantly increased with increasing amounts of rice bran dietary fiber. For textural characteristics, hardness, and chewiness significantly increased with increasing amounts of rice bran dietary fiber. Cohesiveness and resilience were not significantly different between samples. In the sensory evaluation, overall acceptability was highest in the control group and lowest for the 12% sample. In the frequency analysis of the CATA, as rice bran dietary fiber was added, the amount of bran flavor, oliy, and unpleasant increased while frequency of bitterness, sweetness, and chocolate taste decreased. In the principal component analysis, characteristics of unpleasant, oily, soybean flavor, and sweetness were strongly detected in the 12% sample. The control sample showed strong sweetness and bitterness. The results indicate that 3% to 6% rice bran dietary fiber is appropriate for production of brownies.

Physicochemical Characteristics and Antioxidant activities of Sikhye Made with Pigmented Rice (유색미로 제조한 식혜의 이화학적 특성 및 항산화 활성에 관한 연구)

  • Yang, Ji-won;Kim, Young Eon;Lee, Kyung Hee
    • Journal of the East Asian Society of Dietary Life
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    • v.25 no.5
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    • pp.830-841
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    • 2015
  • This study compared the physicochemical characteristics, proximate composition, taste compound and antioxidant properties of Sikhye prepared with pigmented rice. Proximate composition showed a significant difference depending on the type of pigmented rice except crude fat contents and pH, color was a significant difference depending on the type of pigmented rice. The highest brix degree was $15.07^{\circ}Brix$ in red and black rice Sikhye. Each highest value of reducing sugar and free sugar content showed milled rice and brown rice Sikhye. Titratable acidity and total acidity of the pigmented rice Sikhye were highest for black rice Sikhye, free sugar content were highest for green rice Sikhye. Analysis of their relative antioxidative properties indicated that black rice Sikhye had the highest total polyphenol, flavonoid, and anthocyanin content, the highest levels of DPPH radical scavenging ability, and the highest level of reducing power and ferric reducing ability of plasma scores. Principal component analysis suggested that black rice Sikhye had a strong association with antioxidant properties, brown and red rice Sikhye had the strongest association with the sweetness and unique flavor.

Analysis of Quality State for Gochujang Produced by Regional Rural Families (지역별 농가 생산 고추장의 품질 현황 분석)

  • Lee, Seul;Yoo, Seon Mi;Park, Bo Ram;Han, Hye Min;Kim, Ha Yun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.7
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    • pp.1088-1094
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    • 2014
  • This study investigated the quality properties of glutinous rice Gochujang produced by regional rural families in order to determine the present state of quality of traditional Gochujang. A total of 80 Gochujang samples were collected from nationwide rural families and their physicochemical characteristics were analyzed. Based on regional mean, ranges of moisture contents, pH, acidity, crude protein contents, and salinity of Gochujang were $44.31{\pm}5.73%{\sim}50.50{\pm}5.65%$, $4.59{\pm}0.36{\sim}4.79{\pm}0.15$, $1.18{\pm}0.22%{\sim}1.54{\pm}0.36%$, $5.28{\pm}0.90%{\sim}6.93{\pm}.09%$, and $5.55{\pm}0.85%{\sim}8.29{\pm}1.19%$, respectively. The mean contents of amino type N, reducing sugars, and capsaicinoids were $488.81{\pm}79.74mg%{\sim}715.16{\pm}78.09mg%$, $22.32{\pm}9.43%{\sim}28.61{\pm}8.80%$, and $44.31{\pm}18.71mg/kg{\sim}65.15{\pm}47.98mg/kg$, respectively, and differences were significant among the Gochujang samples. Hunter color values (L, a, and b) of Gochujang were $4.84{\pm}3.08$, $21.26{\pm}10.53$, and $8.20{\pm}5.91$, respectively, and the range of viscosity was $31,511{\pm}11,764{\sim}72,923{\pm}32,555$ cP. The acidity, salinity, moisture, crude protein, and amino type N contents of Gochujang produced from the Gangwon-do and Gyeonggi-do areas were significantly higher than those of other regions. According to principal component analysis of the physicochemical characteristics of Gochujang produced by rural families, the salinity, acidity, moisture, crude protein, and amino type N contents were strong characteristics of Gochujang produced by Gangwon-do and Gyeonggi-do. These results indicate that traditional Gochujang produced by rural families shows various quality properties and regional differences in physicochemical characteristics.

Comparative analysis of volatile and non-volatile flavor compounds in rice paste made by α-amylase according to cultivars (α-amylase를 이용하여 제조한 쌀 페이스트의 품종에 따른 휘발성비휘발성 향미성분 비교분석)

  • Son, Eun Young;Kim, Hye Won;Kim, Sun Ah;Lee, Sang Mi;Paek, Se Hee;Kim, Sun Hee;Seo, Yong Ki;Park, Hye-Young;Oh, Sea-Kwan;Kim, Young-Suk
    • Journal of Applied Biological Chemistry
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    • v.60 no.3
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    • pp.283-291
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    • 2017
  • Rice that the half of population in the world eats as a staple food is mostly produced and consumed in Asia. However, its consumption is nowadays decreasing mainly due to diet diversity. Accordingly, some attempts are in demand to enhance the utilization of rice. In this study, profiling of volatile and non-volatile flavor components in rice pastes obtained by ${\alpha}$-amylase was performed and compared according to nine different rice cultivars domestically cultivated in Korea using gas chromatography-mass spectrometry combined by solid phase microextraction and gas chromatography-time of flight-mass spectrometry after a derivatization, respectively. In total, 46 volatile compounds identified included 6 alcohols, 6 aldehydes, 4 esters, 4 furan derivatives, 4 ketones, 1 acid, 1 sulfur-containing compound, 7 hydrocarbons, 5 aromatics and 8 terpenes. The non-volatile flavor components found were composed of 12 amino acids, 6 sugars and 4 sugar alcohols. In principal component analysis, rice paste samples could be discriminated according to cultivars on the score plots of volatile and non-volatile flavor compounds. In particular, some volatile compounds such as pentanal and 4,7-dimethylundecane could contribute to distinguish Senong 17 white and Senong 17 brown, whereas ethanol, 6-methylhep-5-en-2-one, and tridecane could be highly related to the discrimination of Iipum from other cultivars. Among non-volatile compounds, some amino acids such as glycine, serine and ${\gamma}$-aminobutyric acid and some sugars such as sucrose and fructose were mainly responsible for the discrimination of Danmi from the other cultivars. On the other hand, galactose, arabitol and mannose were more closely related to Senong 17 white than Senong 17 brown.