• Title/Summary/Keyword: principal component analysis

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Determination of individual sugars in different varieties of persian grape using Near Infrared spectroscopy

  • Kargosha, Kazem;Azad, Jila;Lary, Abas Motamed
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.1527-1527
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    • 2001
  • Glucose, fructose and sucrose being the main sugars that can be found in natural fruit juice. Many instrumental methods, such as GC, LC, electrochemical or spectrometric methods provide information about both the total content of sugars and the specific concentration of each carbohydrate[1]. The simplicity of sample handling and measurement in the near IR(NIR) wavelength region, which allows the use of long pathlength, optical glass cells and optical fibers, makes NIR a good alternative for sugar determination [2]. In the present study, six varieties of persian grapes were harvested at intervals through august to october and analysed for sugars by NIR. The results were processed by principal component regression (PCR) and partial least squares (PLS) analysis. Sample juice was prepared by squeezing through gauze from crashed grape. This solution was treated by zinc ferrocyanide prior to analysis in order to eliminate colored compounds and all optically active nonsugar substances. For glucose and fructose the most characteristic wavelengths were 1456nm corresponding to the first harmonic O-H stretching and the second at 2062nm corresponding to O-H stretching and deformation; secondary characteristic combination bands were also seen at 2265 nm (O-H and C-C stretching) and at 2240 nm (C-H and C-C stretching). However these spectra were taken over a wavelength range from 1100-2500nm at room temperature of 25-$30^{\circ}C$. To test the accuracy of the described procedure, samples of six varieties of grape were analysed by the proposed NIR and a standard method[2]. Good agreement were found between these two sets of the results. To perform the recovery studies , samples of grape juices previously analysed by the proposed method, were spiked with known amounts of each individual sugars and then analysed again. Relative standard deviations varied from 1.4 to 1.8% for six independent measurements of individual and total sugar concentration. In the analysis of real and synthetic samples, precise and accurate results were obtained , providing accuracy errors lower than 1.9% in all cases. Average recoveries of ${97}{\pm}{4%}$ for total sugar and between ${95}{\pm}{5%}$ and ${99}{\pm}{2%}$ for sing1e sugars demonstrate the applicability of the methodology developed to the direct analysis of grape Juice.

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Validity and Reliability Evaluation of Pregnancy Related Stress Scale (임부 스트레스 측정도구의 신뢰도 및 타당도 평가)

  • Lee, Hyejung;Seo, Minjeong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.6
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    • pp.503-512
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    • 2017
  • The perceived stress of pregnant women is a potential contributor to adverse birth outcomes. Although the importance of the psychosocial well-being of pregnant women has been emphasized, there are fewreliable and valid instruments to measure the stress level of pregnant women in Korea. This study evaluated the psychometric properties of Ahn's pregnancy related stress scale (PSS) that was originally developed in 1984. Two hundred pregnant women completed the survey questionnaire, which was comprised of the PSS, depression scale, and demographic information. Principal component analysis and confirmatory factor analysis was used to test the construct validity. The concurrent validity was evaluated using the correlation with depression scores. Based on exploratory factor analysis and a consideration of conceptual meaning, a five-factor structure was extracted, explaining 57.25% of the variance: physical discomfort, fetus, parenting, spouse relationship, and housework. The goodness-of-fit indices showed an acceptable fit overall with the full model and acceptable internal consistency (Cronbach's alpha =.89). The concurrent validity was confirmed by a comparing with the depression score (r=.48, p <.001). The shortened PSS, as a valid and reliable scale, is recommended to be used to assess pregnancy-related stress and to develop stress managing interventions for pregnant women in clinical settings.

Survey of genetic structure of geese using novel microsatellite markers

  • Lai, Fang-Yu;Tu, Po-An;Ding, Shih-Torng;Lin, Min-Jung;Chang, Shen-Chang;Lin, En-Chung;Lo, Ling-Ling;Wang, Pei-Hwa
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.2
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    • pp.167-179
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    • 2018
  • Objective: The aim of this study was to create a set of microsatellite markers with high polymorphism for the genetic monitoring and genetic structure analysis of local goose populations. Methods: Novel microsatellite markers were isolated from the genomic DNA of white Roman geese using short tandem repeated probes. The DNA segments, including short tandem repeats, were tested for their variability among four populations of geese from the Changhua Animal Propagation Station (CAPS). The selected microsatellite markers could then be used to monitor genetic variability and study the genetic structures of geese from local geese farms. Results: 14 novel microsatellite loci were isolated. In addition to seven known loci, two multiplex sets were constructed for the detection of genetic variations in geese populations. The average of allele number, the effective number of alleles, the observed heterozygosity, the expected heterozygosity, and the polymorphism information content were 11.09, 5.145, 0.499, 0.745, and 0.705, respectively. The results of analysis of molecular variance and principal component analysis indicated a contracting white Roman cluster and a spreading Chinese cluster. In white Roman populations, the CAPS populations were depleted to roughly two clusters when K was set equal to 6 in the Bayesian cluster analysis. The founders of private farm populations had a similar genetic structure. Among the Chinese geese populations, the CAPS populations and private populations represented different clads of the phylogenetic tree and individuals from the private populations had uneven genetic characteristics according to various analyses. Conclusion: Based on this study's analyses, we suggest that the CAPS should institute a proper breeding strategy for white Roman geese to avoid further clustering. In addition, for preservation and stable quality, the Chinese geese in the CAPS and the aforementioned proper breeding scheme should be introduced to geese breeders.

Development of a Method to Analyze Powering Performance of a Ship and its Application to Optimum Hull Form Design (선박(船舶)의 정수중(靜水中) 추진성능(推進性能) 해석(解析) 및 최적선형설계(最適船型設計)에의 응용(應用))

  • Seung-Il,Yang
    • Bulletin of the Society of Naval Architects of Korea
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    • v.22 no.2
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    • pp.35-48
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    • 1985
  • The present work develops a method of evaluating thrust deduction and wake for different loads of the propeller using the concerted application of the theoretical tools and experimental techniques. It also shows the applicability of the new method to the design of optimum hull form. Firstly, the problem of hull-propeller interaction was analyzed in terms of inviscid as well as viscous components of the thrust deduction and wake. The wavemaking resistance of a hull and propeller were mathematically represented by sources on the hull surface and sink on the propeller plane, respectively. The strength of sink was determined by utilizing the radial distributions of propeller load and nominal wake. The resistance increment due to a propeller and the axial perturbation flow induced by the hull in the propeller plane were calculated. Especially, the inviscid component of the thrust deduction was calculated by subtraction the wavemaking resistance of a bare hull, the wavemaking resistance of a free-running propeller and the augmentation of propeller resistance due to hull action from the wavemaking resistance of the hull with a propeller. The viscous components of the thrust deduction and wake were estimated as functions of propeller load which were established by the propeller load varying test after deduction the calculated inviscid components. Secondly, an analysis method of powering performance was developed based on the potential theory and the propeller load varying test. The hybrid method estimates the thrust deduction, wake and propeller open-water efficiency for different propeller load. This method can be utilized in the analysis of powering performance for the propeller load variation such as the added resistance due to hull surface roughness, the added resistance due to wind, etc. Finally, the hybrid method was applied to the optimum design of hull form. A series of afterbody shapes was obtained by systematically varying the waterplane and section shapes of a parent afterbody without changing the principal dimensions, block coefficient and prismatic coefficient. From the comparison of the predicted results such as wavemaking resistance, thrust deduction, wake and delivered power, an optimum hull form was obtained. The delivered power of the optimized hull form was reduced by 5.7% which was confirmed by model tests. Also the predicted delivered power by the hybrid method shows fairly good agreement with the test result. It is therefore considered that the new analysis method of powering performance can be utilized as a practical tool for the design of optimum hull form as for the analysis of powering performance for the propeller load variation in the preliminary design stage.

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Restoration, Prediction and Noise Analysis of Geomagnetic Time-series Data (시계열 지자기 측정 자료의 복원, 예측 및 잡음 분석 연구)

  • Ji, Yoon-Soo;Oh, Seok-Hoon;Suh, Baek-Soo;Lee, Duk-Kee
    • Journal of the Korean earth science society
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    • v.32 no.6
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    • pp.613-628
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    • 2011
  • Restoration, prediction and noise analysis of geomagnetic data measured in the Korean Peninsula were performed. Restoration methods based on an optimized principal component analysis (PCA) and the geostatistical kriging approach were proposed, and its effectiveness was also interpreted. The PCA-based method seemed to be effective to restore the periodical signals and the geostatistical approach was stable to fill the gaps of measurements. To analyze the noise level for each observatory, the geomagnetic time-series was plotted by scattergram which reflects the spatial variation, using data observed during same period. The scattergram showed that the observation made at Cheongyang seemed to have better quality in spatial continuity and stability, and the restoration result was also better than that of Icheon site. For the restoration, both of the methods, geostatistical and optimizaed PCA, showed stable result when the missing of observation was within 20 points. However, in case of more missing observations than 20 points and prediction problem, the optimized PCA seemed to be closer to the real observation considering the frequency-domain characteristics. The prediction using the optimized PCA seems to be plausible for one day of period for interpretation.

Physicochemical and Sensory Characteristics of Doenjang Made by Traditional Methods (전통적인 방법으로 제조된 된장 제품의 이화학적 및 관능적 특성에 대한 연구)

  • Byun, Myung-Woo;Nam, Tan-Gong;Chun, Myoung-Sook;Lee, Gyu-Hee
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.10
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    • pp.1543-1548
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    • 2014
  • To study traditional Doenjang characteristics, Doenjang was purchased from five different provinces: Chungcheong (CC), Gangwon (GW), Gyeonggi (GG), Gyeongsang (GS), and Jeolla (JL). To determine physicochemical characteristics, contents of reducing sugar, amino type nitrogen, salt, pH, and acidity were analyzed. The sensory characteristics were analyzed by sensory descriptive analysis. Reducing sugar content was highest for Doenjang from GW province. Amino type nitrogen content was highest for Doenjang from JL province. The salt content was highest in Doenjang from CC and GS provinces. After principal component analysis (PCA) based on sensory descriptive analysis, salty taste and aftertaste were highly correlated with overall acceptance. In the correlation analysis among chemical compounds and overall acceptance, Doenjang contained low reducing sugar content, and high pH value was positively correlated with overall acceptance. In conclusion, Doenjang with high pH value and salty taste and aftertaste have high overall acceptance.

A Cross-Validation of the Korean Version of the Revised Memory and Behavioral Problems Checklist(K-RMBPC): Exploratory and Confirmatory Analyses ("한국형 기억 및 행동문제 개정점검표(Korean Version of the Revised Memory and Behavioral Problems Checklist: K-RMBPC)"의 타당화를 위한 탐색적 연구)

  • Lee, Min-Hong;Yoon, Eun-Kyung
    • Korean Journal of Social Welfare
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    • v.59 no.2
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    • pp.65-88
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    • 2007
  • This study evaluates psychometric properties of the Revised Memory and Behavioral Problems Checklist(RMBPC) in Korean version. The sample includes 387 South Korean family caregivers who provide the majority of day to day tasks and emotional care for their older family members with physical and/or cognitive disabilities. The psychometric properties of the RMBPC are verified by item analysis, exploratory factor analysis(EFA) & confirmatory factor analysis(CFA). For cross-validity, the randomly divided two samples are used: one sample for EFA(n=193, 387/2) and the other sample for CFA(n=194, 387/2). The internal consistency of the K-RMBPC is excellent, and the convergent and criterion-related validity of the K-RMBPC with related variables is empirically confirmed. An EFA based on the Principal Component Analysis(PCA) method with varimax rotation explains 65.85% of variance accounted for by the three factors. A CFA also verifies that the model fit was acceptable. The shorter Korean version of the RMBPC is found reliable and valid. The translated checklist would be very useful for clinical and research settings by (a) focusing on observable, conceptually relevant, potentially modifiable behaviors and (b) using objective criteria within a self-administered framework, to enable clinicians and researchers to pinpoint areas of disturbance and target intervention goals for patients and caregivers in a cost-effective manner.

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Genetic diversity and population structure of indigenous chicken of Bangladesh using microsatellite markers

  • Rashid, Muhammad Abdur;Manjula, Prabuddha;Faruque, Shakila;Bhuiyan, A.K. Fazlul Haque;Seo, Dongwon;Alam, Jahangir;Lee, Jun Heon;Bhuiyan, Mohammad Shamsul Alam
    • Asian-Australasian Journal of Animal Sciences
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    • v.33 no.11
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    • pp.1732-1740
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    • 2020
  • Objective: The objectives of this study were to investigate the genetic diversity, population structure and relatedness among the five chicken populations of Bangladesh using microsatellite markers. Methods: A total of 161 individuals representing 5 chicken populations (non-descript Deshi [ND], naked neck [NN], hilly [HI], Aseel [AS], and red jungle fowl [JF]) were included in this study to investigate genetic diversity measures, population structure, genetic distance and phylogenetic relationships. Genotyping was performed using 16 selected polymorphic microsatellite markers distributed across 10 chromosomes. Results: The average observed and expected heterozygosity, mean number of alleles and polymorphic information content were found to be 0.67±0.01, 0.70±0.01, 10.7 and 0.748, respectively in the studied populations. The estimated overall fixation index across the loci (F), heterozygote deficiency within (FIS) and among (FIT) chicken populations were 0.04±0.02, 0.05 and 0.16, respectively. Analysis of molecular variance analysis revealed 88.07% of the total genetic diversity was accounted for within population variation and the rest 11.93% was incurred with population differentiation (FST). The highest pairwise genetic distance (0.154) was found between ND and AS while the lowest distance was between JF and AS (0.084). Structure analysis depicted that the studied samples can be categorized into four distinct types or varieties (ΔK = 3.74) such as ND, NN, and HI where AS and JF clustered together as an admixed population. The Neighbor-Joining phylogenetic tree and discriminant analysis of principal component also showed close relatedness among three chicken varieties namely AS, HI, and JF. Conclusion: The results reflected that indigenous chicken of Bangladesh still possess rich genetic diversity but weak differentiation among the studied populations. This finding provides some important insight on genetic diversity measures that could support the designing and implementing of future breeding plans for indigenous chickens of Bangladesh.

Comparison study of modeling covariance matrix for multivariate longitudinal data (다변량 경시적 자료 분석을 위한 공분산 행렬의 모형화 비교 연구)

  • Kwak, Na Young;Lee, Keunbaik
    • The Korean Journal of Applied Statistics
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    • v.33 no.3
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    • pp.281-296
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    • 2020
  • Repeated outcomes from the same subjects are referred to as longitudinal data. Analysis of the data requires different methods unlike cross-sectional data analysis. It is important to model the covariance matrix because the correlation between the repeated outcomes must be considered when estimating the effects of covariates on the mean response. However, the modeling of the covariance matrix is tricky because there are many parameters to be estimated, and the estimated covariance matrix should be positive definite. In this paper, we consider analysis of multivariate longitudinal data via two modeling methodologies for the covariance matrix for multivariate longitudinal data. Both methods describe serial correlations of multivariate longitudinal outcomes using a modified Cholesky decomposition. However, the two methods consider different decompositions to explain the correlation between simultaneous responses. The first method uses enhanced linear covariance models so that the covariance matrix satisfies a positive definiteness condition; in addition, and principal component analysis and maximization-minimization algorithm (MM algorithm) were used to estimate model parameters. The second method considers variance-correlation decomposition and hypersphere decomposition to model covariance matrix. Simulations are used to compare the performance of the two methodologies.

Metabolic Discrimination of Rice Cultivars and Relative Quantification of Major Sugar Compounds Using 1H NMR Spectroscopy Combined by Multivariate Statistical Analysis (1H NMR 스펙트럼 데이터의 다변량 통계분석에 의한 벼 품종의 구분 및 주요 당 화합물의 정량분석)

  • Kim, Suk-Weon;Koo, Bon-Cho;Kim, Jong-Hyun;Liu, Jang-Ryol
    • Journal of Plant Biotechnology
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    • v.33 no.4
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    • pp.283-288
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    • 2006
  • Discrimination of 5 rice cultivars (Sangjubyeo , Dongjinbyeo Simbaekbyeo , Hwamanbyeo , and Simbaek-hetero ) using metabolic profiling was carried out. Whole cell extracts from each cultivar were subjected to $^1H$ NMR spectroscopy. When spectral data were analyzed by principal component analysis, 5 cultivars were clustered into 3 groups: SJ, DJ + SB, and HM + SH. Thecultivars showed great difference in carbohydrate region of $^1H$ NMR spectra, suggesting that qualitative and quantitative differences in carbohydrate compounds play a major role in discrimination of the cultivars. In addition, it was readily possible to determine relative quantification of major carbohydrates including sucrose, glucose, maltose from spectral data of the cultivars. SJ showed 2 to 4 times higher content of maltose than the other rice cultivars. Overall results indicate that metabolic discrimination of rice cultivars using $^1H$ NMR spectroscopy combined by multivariate statistical analysis can be used for rapid discrimination of numerous rice cultivars and simple quantitative analysis system of major carbohydrate compounds in rice grains.