• Title/Summary/Keyword: Partial Correlation

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The rank determination for the source identification utilizing partial coherence function technique (부분 기여도 함수를 이용한 소음/진동원 검출에 있어서의 우선순위 결정에 관한 연구)

  • 박정석;김광준
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1990.10a
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    • pp.3-8
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    • 1990
  • 소음/진동 문제를 해결하는 데 있어서 우선은 소음/진동원들의 위치를 알아 내고 그들 중에 비중이 가장 큰 소음/진동원을 파악하는 것이 중요하다. 다 입력/단일출력 모형을 이용한 소음/진동원 규명에 대한 방법에는 주파수 응 답함수를 이용하는 방법(frequency response function approach)과 부분 기여 도 함수(partial coherence function)를 이용하는 방법 등이 있는데, 입력들 사이의 상호상관(correlation)이 없는 경우에는 전자의 방법을 사용하여 출력 에 가장 큰 비중을 차지하는 소음/진동원을 알아낼 수 있으나 상호상관이 존 재하는 경우에는 후자의 방법을 사용하게 된다. 그러나 후자의 방법을 적용 함에 있어서도 기본적으로 소음/진동원들의 위치를 알아야 하는 것 이외에 그들 사이의 원인.효과관계(causaling), 또는 우선순위(rank)를 우선적으로 아 는 것이 중요한데 이는 입력들 사이의 우선순위를 어떻게 두느냐에 따라 해 석 결과가 다르게 나타나기 때문이다 [1,2,3]. 본 연구에서는 부분 기여도 함 수를 이용하여 소음/진동원을 규명할 때 그들 사이의 우선순위를 결정하는 방법을 제시하고 2입력/1출력 모형에 대해 적용하여 보았다.

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Prediction of Chemical Compositions for On-line Quality Measurement of Red Pepper Powder Using Near Infrared Reflectance Spectroscopy (NIRS)

  • Lee, Sun-Mee;Kim, Su-Na;Park, Jae-Bok;Hwang, In-Kyeong
    • Food Science and Biotechnology
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    • v.14 no.2
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    • pp.280-285
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    • 2005
  • Applicability of near infrared reflectance spectroscopy (NIRS) was examined for quality control of red pepper powder in milling factories. Prediction of chemical composition was performed using modified partial least square (MPLS) techniques. Analysis of total 51 and 21 red pepper powder samples by conventional methods for calibration and validation, respectively, revealed standard error of prediction (SEP) and correlation coefficient ($R^2$) of moisture content, ASTA color value, capsaicinoid content, and total sugar content were 0.55 and 0.90, 8.58 and 0.96, 31.60 and 0.65, and 1.82 and 0.86, respectively; SEP and $R^2$ were low and high, respectively, except for capsaicinoid content. The results indicate, with slight improvement, on-line quality measurement of red pepper powder with NIRS could be applied in red pepper milling factories.

The Comparison of Nutrients intake and Dietary Environment between Rural and Asylum Elderly in partial area of Kyunggi (경기일부지역 농촌노인과 양로원 노인의 영양섭취상태와 식생활환경요인의 비교)

  • 박양자;이승교
    • Korean Journal of Rural Living Science
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    • v.7 no.1
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    • pp.39-50
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    • 1996
  • This study was carried out to investigate nutrients intake and dietary environments of rural and asylum elderly in partial Kyunggi area. Results were as followes: (1) Educational level of 2 groups of rural and asylum elderly was only literacy, And rural elderly worked more than the aged of asylum. (2) The nutrients intake of rural elderly was very small quantity: Energy intake was 62% of RDA, that of protein 59%, calcium 56%, and iron 72% only. This nutrients intake state was lower than that of asylum elderly. (3) Health score CMI was selected 31 cases of items for aged. Ryal elderly received 11.7/31, but the scores of asylum elderly were 7.1 only. It means that asylum elderly felt more healthy than rural. (4) The correlation Serum TG was significant with protein fat and calcium, but serum calcium was not significant with intake of calcium. The nutrients intake was correlated with CMI score and dietary habit score.

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Assessment of Insulation Condition in Large Turbine Generator Stator Windings (대용량 터빈발전기 고정자 권선의 절연상태 평가)

  • Kim, Hee-Dong;Lee, Young-Jun;Park, Deok-Hyun
    • Proceedings of the KIEE Conference
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    • 1999.07e
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    • pp.2093-2096
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    • 1999
  • This paper describes to access the insulation deterioration condition of the stator windings in three large turbine generators. Nondestructive tests have been carried out on stand-still generators which have been in service for 2 to 30 years. In most cases these tests include ac current increase rate($\Delta$I), delta tan delta( ${\Delta}tan{\delta}$), and maximum partial discharge(Qm). Gen. 2 show that the $tan{\delta}$ is higher than other two generators in the $tan{\delta}$-voltage curve. Partial discharge(PD) patterns were observed internal, corona and treeing discharges in large turbine generators. The PD tests were confirmed the correlation between discharge patterns and the kinds of defects.

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Propagation Characteristics of Acoustic Signals Produced by Partial Discharge in Insulation Oil (유중 부분방전 음향신호의 전달특성)

  • Kim, Sung-Wook;Park, Chan-Yong;Park, Dae-Won;Kil, Gyung-Suk;Rhyu, Keel-Soo
    • Proceedings of the KSR Conference
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    • 2009.05a
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    • pp.841-847
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    • 2009
  • This paper describes the propagation characteristics of acoustic signals as a function of distance from the location of partial discharge(PD) occurrence to analyze correlation between discharge magnitude and acoustic signal in insulation oil. To measure small acoustic signals produced by PD, we fabricated an amplifier and simulated PD at a needle-plane electrode system set in insulation oil. The amplifier has the gain of 40 dB and the frequency bandwidth of 1.6 kHz$\sim$1.6 MHz. These are enough characteristics for the measurement of acoustic signals. After a comparative calibration experiment by a standard pulse generator and a coupling capacitor, we analyzed the propagation characteristics of acoustic signals in insulation oil.

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Quantitative Analysis of Indomethacin by the Portable Near-Infrared (NIR) System (근적외분광분석법을 이용한 인도메타신의 정량분석)

  • 김도형;우영아;김효진
    • YAKHAK HOEJI
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    • v.47 no.5
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    • pp.261-265
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    • 2003
  • Near-infrared (NIR) system was used to determine rapidly and simply indomethacin in buffer solution for a dissolution test of tablets and capsules. Indomethacin standards were prepared ranging from 10 to 50 ppm using the mixture of phosphate buffer (pH 7.2) and water (1 : 4). The near-infrared (NIR) transmittance spectra of indomethacin standard solutions were collected by using a quartz cell in 1 mm and 2 mm pathlength. Partial least square regression (PLSR) was explored to develop calibration models over the spectral range 1100∼1700 nm. The model using 1 mm quartz cell was better than that using 2 mm quartz cell. The PLSR models developed gave standard error of prediction (SEP) of 0.858 ppm. In order to validate the developed calibration model, routine analysis was performed using another standard solutions. The NIR routine analysis showed good correlation with actual values. Standard error of prediction (SEP) is 1.414 ppm for 7 indomethacin samples in routine analysis and its error was permeable in the regulation of Korean Pharmacopoeia (VII). These results show the potential use of the real time monitoring for indomethacin during a dissolution test.

Properties of PD Pulses Accompanying with Bush-type Tree in LDPE (저밀도 폴리에틸렌에서 부시형 전기트리에 수반되는 부분방전 펄스의 특성)

  • 강성화;박영국;정수현;이광우;임기조
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.11 no.12
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    • pp.1055-1059
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    • 1998
  • The correlation between the propagation of electrical tree and distributions of partial discharge(PD) pulses accompanying with electrical tree of bush type in low density polyethylene were discussed. We measured the growth of electrical tree by using optical microscope and PD data simultaneously. The PD data detected and analyzed were PD magnitude, repetition rate, average discharge power, average phase angle, and $\psi$-q-n distribution pattern. The average discharge power and repetition rate of PD had good linear relation with area of tree. Repetition rate and peak discharge magnitude and width of discharge phase angle increased with the tree.

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Tree Shape and Partial Dishcharge in LDPE Blended with Organic Compounds (유기화합물이 첨가된 LDPE에서의 트리 형상과 부분방전)

  • Kang, S.H.;Choi, H.S.;Shin, Y.S.;Jeong, D.Y.;Lim, K.J.;Park, D.H.
    • Proceedings of the KIEE Conference
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    • 1993.07b
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    • pp.1130-1133
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    • 1993
  • In this paper, it is discussed the correlation between shape of tree and internal partial discharge in low density polyethylene(LDPE) blended with organic compounds that used to improve the effect of resistance to treeing. Initiation and growing of tree are retarded in specimens blended with organic compounds that comprised radical having large electron affinity, and also discharge magnitude and counts of discharging pulse per unit time in these samples are more than those in others. It is observed that the shape of tree in these samples is bush type, but in case of pure LDPE samples dendrite type.

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Association of PAH-DNA adducts and Urinary PAH metabolites influenced by polymorphisms of xenobiotic metabolism enzymes in industrial wase incinerating workers (산업폐기물 소각장 근로자에서 요중 PAHs 대사산물과 혈중 aromatic-DNA adducts)

  • ;Masayoshi Ichiba
    • Environmental Mutagens and Carcinogens
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    • v.22 no.4
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    • pp.303-311
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    • 2002
  • This study evaluated the concentrations of urinary metabolites of polycyclic aromatic hydrocarbons (PAHs) in industrial waste incineration workers. The effect of genetic polymorphisms of xenobiotic metabolism enzymes on urinary concentration of PAH metabolites was assessed. And, aromatic DNA adduct levels were also determined in total white blood cells. Fifty employees were recruited from a company handling industrial wastes located in Ansan, Korea: non-exposed group (n=21), exposed group (n=29). Sixteen ambient PAHs were determined by GC/MSD (NIOSH method) from personal breathing zone samples of nine subjects near incinerators. Urinary 1-hydroxypyrene glucuronide (1-OHPG), a major pyrene metabolite, was assayed by synchronous fluorescence spectroscopy after immunoaffinity purification using monoclonal antibody 8E11 (SFS/IAC). Multiplex PCR was used for genotyping for GSTMI/TI and PCR-RFLP for genotyping of CYP1A1 (MspI and Ile/Val). PAH-DNA adducts in peripheral blood WBC were measured by the nuclease P1-enhanced postlabeling assay. Smoking habit, demographic and occupational information were collected by self-administered questionnaire. The range of total ambient PAH levels were 0.00-7.00 mg/㎥ (mean 3.31). Urinary 1-OHPG levels were significantly higher in workers handling industrial wastes than in those with presumed lower exposure to PAHs (p=0.006, by Kruskal-Wallis test). There was a statistically significant dose-response increase in 1-OHPG levels with the number of cigarettes consumed per day (Pearson correlation coefficient=0.686, p<0.001). Urinary 1-OHPG levels in occupationally exposed smoking workers were highest compared with non-occupationally exposed smokers (p=0.053, by Kruskal-Wallis test). Smoking and GSTMI genotype were significant predictors for log-transformed 1-OHPG by multiple regression analysis (overall model R²=0.565, p<0.001), whereas smoking was the only significant predictor for log-transformed aromatic DNA adducts (overall model R²=0.249, p=0.201). Aromatic DNA adducts was also a significantly correlation between log transferred urinary 1-OHPG levels (pearson's correlation coefficient=0.307, p=0.04). However, the partial correlation coefficient adjusting for Age, Sex, and cigarette consumption was not significant (r=0.154, p=0.169). The significant association exists only in individuals with the GSTMI null genotype (pearsons correlation coefficient=0.516, p=0.010; partial correlation coefficient adjusting for age, sex, and cigarette consumption, r=0.363, p=0.038). Our results suggest that the significant increase in urinary 1-OHPG in the exposed workers is due to higher prevalence of smokers among them, and that the association between urinary PAH metabolites and aromatic DNA adducts in workers of industrial waste handling may be modulated by GSTMI genotype. There results remain to be confirmed in future larger studies.

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The Effects of Children's Self-Esteem on Their School Adjustment: Focusing on the Mediation of Peer Attachment (초등학생의 자아존중감이 학교생활적응에 미치는 영향: 또래애착의 매개효과를 중심으로)

  • Kwon, Hye Jin;Sung, Mi Young
    • Human Ecology Research
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    • v.52 no.4
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    • pp.395-403
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    • 2014
  • The purpose of this study was to analyze the effects of children's self-esteem on their school adjustment, focusing on the mediation of peer attachment. A total of 2,200 3rd grade children from the third Korea Child-Adolescent Panel Survey participated in this study. The instruments used in this study were the Self-esteem Scale, Peer Attachment Scale, and School Adjustment Scale. The collected data were analyzed by using a Student's t -test, Pearson's partial correlation, simple regression, and hierarchical multiple regression with SPSS ver. 16.0 software. The main results of this study are as follows: first, the boys had higher self-esteem, peer attachment, and school adjustment scores than the girls. Second, there was a significant positive correlation between children's self-esteem and peer attachment as well as a significant positive correlation between children's self-esteem and school adjustment. Further, there was a significant positive correlation between children's peer attachment and school adjustment. Finally, children's self-esteem exerted positive effects on their peer attachment, and children's peer attachment had a positive influence on their school adjustment. The effect of children's self-esteem on their school adjustment was partially mediated by their peer attachment. These findings provide preliminary evidence that the relationships between children's self-esteem and school adjustment may be mediated by their peer attachment.