• 제목/요약/키워드: Relationship coefficient

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Effect of Knit Structure on the Drapability of Weft Knitted Fabrics (편성조직의 위편성물의 드레이프성에 미치는 영향)

  • Suh, Jung-Kwon
    • Journal of the Korea Fashion and Costume Design Association
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    • v.14 no.1
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    • pp.111-121
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    • 2012
  • This study focused on the plane and side drape coefficients of weft knitted fabrics as a function of knit structure, stitch density, and stiffness. Fifteen weft knitted fabrics are produced with five different structures (interlock, single pique, royal interlock, cross miss interlock, and mock royal interlock) and three different gauges (7G, 10G, and 12G). Five knit structures were the application of knit, tuck, and miss stitch on the basis of interlock of the double knit fabric For this purpose, three-dimensional shapes of the draped sample were obtained by using a drapability tester which can record the contour line coordinates of a projected plane drape. Then, projected shapes of the plane and side drape were derived from those three-dimensional ones to review the relationship between plane drape coefficients and side ones. It was found that the theoretical values of plane and side drape coefficients depending on the change of deflection angles fit to their experimental ones. A5 a result of a regression analysis of the relationship between plane and side drape coefficients, the relationship could be expressed as $y=0.5838x-0.0065x^2+9.03{\times}10^{-5}x^3$. In case of mean of drape coefficient, it was increased according to the rule of that the more tuck and miss stitch overlap. A high degree of correlation was found between stiffness and drape coefficient. The regression equation of drape coefficient($y$) can be represented by $y=y=\sqrt[3]{Stiffness}-10.72$.

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Fabrication and Analysis of Multilayer Ceramic Capacitors for Medium and High Voltage (중, 고압용 적층 세라믹 캐패시터 제작 및 분석)

  • Yoon, Jung-Rag;Kim, Min-Ki;Lee, Heun-Young;Lee, Serk-Won
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.18 no.8
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    • pp.685-689
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    • 2005
  • In the fabrication and design of MLCCs (Multilayer Ceramic Capacitors) with Ni inner electrode for medium and high voltage, reliability and dielectric breakdown mode have been investigated. For thickness of green sheet, the relationship between the rated voltage versus the thickness of green sheet. Increasing the thickness of green sheet increases the dielectric breakdown voltage. However, a practical limit to this linear relationship occurs at 30 urn and above. As the thickness of green sheet increased, dielectric breakdown voltage and weibull coefficient is increased, but abruptly decrease at 30 urn and 36 urn. When 24 urn of green sheet thickness, weibull coefficient and dielectric breakdown voltage were 13.58 and 70 V/um respectively. The results enabling the MLCCs to demonstrate high levels of reliability at medium and high voltage.

Prediction of Yield from Leaf weight and Leaf area (건엽중 및 엽면적에 의한 잎담배 수량예측)

  • 이철환;이병철
    • Journal of the Korean Society of Tobacco Science
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    • v.11 no.2
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    • pp.115-126
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    • 1989
  • This study was conducted to determine the time and methods of predicting tobacco yield, by studying the relationship of yield components to yield. 1. The relationship between each position in leaf dry weight and approached gradually each other and also correlation coefficient of top leaf was higher than that of lower leaf. The leaf dry weight per plant was highly correlated with leaf area from 16th leaf position on stalk. Leaf dry weight of each leaf position on stalk was highly correlated with leaf dry weight per plant at 14 to 16th leaf position. 2. The correlation coefficient between leaf dry weight and leaf area per plant was higher at the late growth stage than at the early growth stage, and higher between the near stages. Correlation coefficient between leaf dry weights was higher than that of leaf areas. 3. Flue-cured tobacco yield be estimated from leaf dry weight per plant at 50 to 55 days after transplanting. 4. Air-cured tobacco yield could be predicted from leaf dry weight per plant at 60 days after transplanting.

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Effects of Friction Coefficient on Creep Life Assessment of Sheet (박판 크리프 수명평가에 마찰계수의 영향)

  • Jeong, J.Y.;Im, J.W.;Keum, Y.T.
    • Transactions of Materials Processing
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    • v.19 no.7
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    • pp.435-440
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    • 2010
  • The creep life of 9Cr1MoVNb steel, in terms of Larson-Miller parameter(LMP), was evaluated by small punch(SP) creep simulation and verified by uniaxial creep test. By employing the elastoplastic FEM(finite element method), the small punch creep behaviors associated with various friction coefficients were simulated to identify a real friction phenomena. The friction coefficient, ${\mu}$=0.7, determined by comparing deflection history was used in the small punch creep simulation to find the equivalent stresses with which the relationship between punch load and uniaxial creep stress was found. The creep life was then predicted by the LMP, which was the relationship among the rupture time, temperature, and stress. Finally, the LMP calculated by SP-creep simulation was compared with that had computed by the uniaxial creep test and fairly matched LMPs were found.

MFSC: Mean-Field-Theory and Spreading-Coefficient Based Degree Distribution Analysis in Social Network

  • Lin, Chongze;Zheng, Yi
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.8
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    • pp.3630-3656
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    • 2018
  • Degree distribution can provide basic information for structural characteristics and internal relationship in social network. It is a critical procedure for social network topology analysis. In this paper, based on the mean-field theory, we study a special type of social network with exponential distribution of time intervals. First of all, in order to improve the accuracy of analysis, we propose a spreading coefficient algorithm based on intimate relationship, which determines the number of the joined members through the intimacy among members. Then, simulation show that the degree distribution of follows the power-law distribution and has small-world characteristics. Finally, we compare the performance of our algorithm with the existing algorithms, and find that our algorithm improves the accuracy of degree distribution as well as reducing the time complexity significantly, which can complete 29.04% higher precision and 40.94% lower implementation time.

A Numerical Study on Nonlinear Flow in Porous Medium (다공성 매질에서 비선형 흐름에 대한 수치적 연구)

  • Jeong, Woo Chang
    • Proceedings of the Korea Water Resources Association Conference
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    • 2017.05a
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    • pp.384-384
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    • 2017
  • In this study, the numerical investigation of nonlinear flow in a porous medium was carried out. The applied numerical model is ANSYS CFX which is a three-dimensional fluid dynamic model, and the verification of this model was carried out by using the experimental data obtained from Mayer et al works(2011). The experimental and numerical results of velocity and Reynolds number-friction coefficient relationship show relatively a good agreement. Based on the experimental results, we analysed numerically the velocity and Reynolds number-friction coefficient relationship with the variation of permeability, dynamic viscosity and porosity and quantitatively the variation by applying the best curve fitting for each case.

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Active Days around Solar Minimum and Solar Cycle Parameter

  • Chang, Heon-Young
    • Journal of Astronomy and Space Sciences
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    • v.38 no.1
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    • pp.23-29
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    • 2021
  • Utilizing a new version of the sunspot number and group sunspot number dataset available since 2015, we have statistically studied the relationship between solar activity parameters describing solar cycles and the slope of the linear relationship between the monthly sunspot numbers and the monthly number of active days in percentage (AD). As an effort of evaluating possibilities in use of the number of active days to predict solar activity, it is worthwhile to revisit and extend the analysis performed earlier. In calculating the Pearson's linear correlation coefficient r, the Spearman's rank-order correlation coefficient rs, and the Kendall's τ coefficient with the rejection probability, we have calculated the slope for a given solar cycle in three different ways, namely, by counting the spotless day that occurred during the ascending phase and the descending phase of the solar cycle separately, and during the period corresponding to solar minimum ± 2 years as well. We have found that the maximum solar sunspot number of a given solar cycle and the duration of the ascending phase are hardly correlated with the slope of a linear function of the monthly sunspot numbers and AD. On the other hand, the duration of a solar cycle is found to be marginally correlated with the slope with the rejection probabilities less than a couple of percent. We have also attempted to compare the relation of the monthly sunspot numbers with AD for the even and odd solar cycles. It is inconclusive, however, that the slopes of the linear relationship between the monthly group numbers and AD are subject to the even and odd solar cycles.

Analysis of Correlation Relationship for Flow and Water Quality at Up and Down Streams (수계 상하류의 유량 및 수질 상관관계 분석)

  • Chang, In-Soo;Jung, Jin-Kyeng;Park, Ki-Bum
    • Journal of Environmental Science International
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    • v.19 no.6
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    • pp.771-778
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    • 2010
  • The prediction of discharge is very important in water resources management and plan. In this study, we have analyzed discharge data of site at up and down stream in watershed. In order to forecast discharge the regression equations were developed by measuring flow data. Also, to forecast the change of water quality followed by change of inflow the correlation relationship between inflow of the Youngchun site and the Chunhju dam was shown as very high. The forecast of inflow at the Chungju dam would be possible through flow analysis of the Youngchun site. And, it is possible to forecast water quality by flow analysis because the correlation relationship of SS and turbidity followed by change of flow for each station of investigation was very high.

Mass transfer characteristics of continuous electrocoagulation for dyestuff solution using aluminum flat plate electrode (Al 전극에 의한 염료의 전기응집에서 물질전달 특성)

  • Kim, Tak-Hyun;Park, Chulhwan;Shin, Eung-Bai;Kim, Sangyong
    • Proceedings of the KAIS Fall Conference
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    • 2001.05a
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    • pp.290-291
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    • 2001
  • The relationship between velocity, viscosity, diffusion coefficient, mass transfer coefficient and characteristic length and mass transfer data can be correlated by dimensionless relationship in electrolytic process. The performance of dyestuff removal was decreased as the flow rate of electrolyte was increased. It was due to the effect of retention time decreasing was superior to that of turbulent inlet mixing. Sh/Sc$\^$1/3/ vs Re plot for Al flat electrode did not showed the general tendency of the relationship between Sh/Sc$\^$1/3/ and Re. It can be thought that flow rate was not sufficiently high to increase the effect of mixing.

Predicting of Uncorrected Astigmatism from Decimal Visual Acuity in Spherical Equivalent

  • Moon, Byeong-Yeon;Kim, Sang-Yoeb;Cho, Hyun Gug
    • Journal of the Optical Society of Korea
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    • v.17 no.2
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    • pp.219-223
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    • 2013
  • The purpose of this study was to determine the relationship between the spherical equivalent visual acuity (VA) and uncorrected astigmatism. On 108 emmetropic eyes, the spherical equivalent VA was measured for cross cylindrical lens (CC lens)-induced astigmatic eyes and the VA-astigmatism relation determined. On 158 astigmatic eyes, the spherical equivalent VA and corrected astigmatism were measured and the measured values were compared with the calculated values from the VA-astigmatism relation by correlation coefficient analysis. Subsequent to that, the relationship between spherical equivalent VA and uncorrected astigmatism was made. The relationship was fitted for an exponential equation. Correlation coefficient between calculated values by equation and measured values for astigmatic eyes was 0.991 (p<0.01). The relationship between the spherical equivalent VA and the uncorrected astigmatism was decided as follows (spherical equivalent VA / uncorrected astigmatism): 1.0 / 0.25 D, 0.9 / 0.50 D, 0.8 / 0.75 D, 0.7 / 1.00 D, 0.6 / 1.25 D, 0.5 / 1.50 D, 0.4 / 2.00 D, 0.3 / 2.50 D, 0.2 / 3.00 D, 0.1 / 4.00 D, and 0.05 / 4.75 D. In conclusion, the relationship table devised from this study is a useful reference for predicting uncorrected astigmatism by measurement of decimal VA in spherical equivalent.