• Title/Summary/Keyword: Correlation equation

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Experimental Studies of the Short-Term Fluctuations of Net Photosynthesis Rate of Norway Spruce Needles under Field Conditions (야외조건하(野外條件下)에서 독일가문비(Picea abies Karst) 침엽(針葉)의 순(純) 광합성률(光合成率)의 단기(短期) 변화(變化)에 대한 실험적(實驗的) 연구(硏究))

  • Bolondinsky, V.;Oltchev, A.;Jin, Hyun O.;Joo, Yeong Teuk;Chung, Dong Jun
    • Journal of Korean Society of Forest Science
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    • v.88 no.1
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    • pp.38-46
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    • 1999
  • Canopy structure conductances of a Norway spruce forest in the Solling Hills(Central Germany) and Central Forest Biosphere Reserve(320km to the north-west from Moscow) were derived from LE(latent heat flux) and H(sensible heat flux) fluxes measured(by Eddy correlation technique and energy balance method) and modelled(by one dimensional non-steady-state) SVAT(soil-vegetation-atmosphere-transfer) model(SLODSVAT) using a rearranged Penman-Monteith equation("Big-leaf" approximation) during June 1996. They were compared with canopy stomatal conductances estimated by consecutive intergrating the stomatal conductance of individual needles over the whole canopy("bottom-up" approach) using SLODSVAT model. The result indicate a significant difference between the canopy surface conductances derived from measured and modelled fluxes("top-down" approach) and the stomatal conductances modelled by the SLODSVAT("bottom-up" approach). This difference was influenced by some nonphysiological factors within the forest canopy(e.g. aerodynamic and boundary layer resistances, radiation budget, evapotranspiration from the forest understorey). In general, canopy surface conductances derived from measured and modelled fluxes exceeded canopy stomatal conductance during the whole modelled period, The contribution of the understorey's evapotranspiration to the total forest evapotranspiration was small (up to 5-9% of the total LE flux) and was not depended on total radiation balance of forest canopy. Ignoring contribution of the understorey's evapotranspiration resulted in an overestimation of the canopy surface conductance for a spruce forest up to 2mm/s(about 10-15%).

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Isothermal Vapor-liquid Equilibria for the Binary Mixtures of 3-Methylpentane with Ethylene Glycol Monopropyl Ether and Ethylene Glycol Isopropyl Ether (3-메틸펜테인과 에틸렌 글리콜 모노프로필 에테르 및 에틸렌 글리콜 아이소프로필 에테르 혼합물에 대한 2성분계 등온 기-액 상 평형)

  • Hyeong, Seonghoon;Jang, Sunghyun;Kim, Hwayong
    • Korean Chemical Engineering Research
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    • v.53 no.3
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    • pp.302-308
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    • 2015
  • Isothermal vapor liquid equilibria for the binary system of 3-methylpentane with ethylene glycol monopropyl ether ($C_3E_1$) and ethylene glycol isopropyl ether ($iC_3E_1$) were measured at 303.15, 318.15, and 333.15K. In our previous work, phase equilibria for the binary system of $C_3E_1$ mixtures were investigated according to the chain length of alkane, alcohol or those isomer. But in this study, we discussed the different effect of $C_3E_1$ and its isomer, $iC_3E_1$, on the phase equilibria. The measured systems were correlated with a Peng-Robinson equation of state (PR EOS) combined with Wong-Sandler mixing rule for the vapor phase, and NRTL, UNIQUAC, and Wilson activity coefficient models for the liquid phase. All the measured systems showed good agreement with the correlation results. And it was found that the phase equilibria showed very little difference between the $iC_3E_1$ mixture system and the $C_3E_1$ mixture system.

Evaluation of Ballistic Resistance Performance by Thickness and Proportion of Magnetic Aggregate of Concrete (콘크리트 두께와 자철광 함량에 따른 방탄 성능 평가)

  • Lim, Cha-Yeon;Kim, Kuk-Joo;Roh, Jeong-Heon;Jang, Chang-Su;Park, Young-Jun
    • Journal of the Korea Institute of Building Construction
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    • v.20 no.1
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    • pp.43-51
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    • 2020
  • The main purpose of protective facility for small military unit is to provide the protection of not all the weapons system but the near-miss bullet in Korean army. In particular about the small caliber bullets, especially KM80 in Korea, there were many studies that both of the experiential and structural design methods dose not reflect enough the military threat. For that reason, a new equation to calculate effective anti-piercing depths for RC slabs against small caliber bullets is proposed in earlier research with actual shooting test. But, the test only considers the strength of concrete without the thickness of concrete, types of aggregate, the angle of yaw of bullet, high-strength concrete, etc. Therefore, this study evaluated the ballistic resistance performance by thickness and proportion of magnetic aggregate of concrete. As a result, we identified two major statistical estimations that the error of piercing depth by the angle of yaw of bullet could be cancelled by barrage and the thickness and proportion of magnetic aggregate of concrete dose not effect on the protection ability of concrete structure.

An Analysis of Structural Relationships of the Cognitive and Communication Ability Related Variables on Infants (영아기 인지·의사소통 발달 관련요인 간의 구조적 관계 분석)

  • Back, Ji Sook;Kwon, Eun Joo
    • Korean Journal of Child Education & Care
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    • v.18 no.1
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    • pp.103-123
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    • 2018
  • This study investigated the structural relationships among infant's cognitive and communication ability, temperament, teacher-infants interaction, and mothers' parenting stress. Subjects used in this study were 249 infnats whose mean age of 30.21 months, and who were attended in preschool in S city. Research instruments used in collecting data were 'K-ASQ(Korean Ages and Stages Questionnaires)', 'EAS(Emotionality, Activity, and Sociability-Temperament Survey for Children-Parental Ratings)', 'PSI/SF(Parenting Stress Index/ Short Form)', 'ECOI'. The collected data were analyzed through SPSS 18.0 and AMOS 18.0 program. Pearson's correlation and Structural equation model analysis were used to analyze the data. Findings are as follows. First, there were positive correlations between infant's cognitive and communication ability with social-ability temperament, teacher-infants interaction. There were negative correlations between infant's cognitive and communication ability with infant's emotionality temperament, mothers' parenting stress. Second, social-ability temperament directly affected disposition toward cognitive ability, but in-direct effect was not significant. Emotionality temperament partially mediated the effects of parenting stress toward cognitive ability. Third, social ability directly affected disposition toward language ability, but in-direct effect was not significant. There has no significant path of temperament to teacher-child interaction, but teacher-child interaction has direct effect to infant's cognitive ability. Finally, all path about infant's communication ability were not significant.

Analysis of Component Factors Concerned in Taste of Korean Hot Pepper by Sensory Evaluation (관능평가를 이용한 고추의 맛에 관여하는 성분 요인 분석)

  • Soh, Jae-Woo;Choi, Ki-Young;Lee, Yong-Beom;Nam, Sang-Yong
    • Journal of Bio-Environment Control
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    • v.20 no.4
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    • pp.297-303
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    • 2011
  • The contents of capsaicinoid, free sugars and organic acids of six varieties of Korean hot pepper, Supermanita, Dokyacheongcheong, Shinseokyeoi, Wangdaebak, Hanbando, and Chungyang, were measured. The sensory evaluations of its extracts were compared in order to investigate the indirect effect or reaction of the composition of taste components on sensory acceptability of Korean hot pepper. The contents of capsaicinoid were considerably from $37.8mg{\cdot}100g^{-1}$ to $164.1mg{\cdot}100g^{-1}$, and the contents of free sugars were from 9.3% to 18.2%, and the contents of organic acids were from 8.1% to 14.7% in Korean hot peppers. Although the pungent sensory evaluation of water extract of pepper powder was completely accordant with instrumental analysis result of capsaicinoid contents, they did not show a significant relationship to the sensory of taste. Multiple regression with capsaicinoid (CAP), total sugars (TS) and total organic acid (TOA) contents increased the correlation coefficient for sensory of taste to r = 0.927 and the coefficient of determination for them to $R^2=0.906$. However, we suggest the more efficient function for it which is composed of two independent variables only. As the result, a regression equation of Y = 0.69 X + 0.11 with $R^2=0.884$ was obtained for quantitative analysis of sensory evaluation of pepper taste by two factors between capsaicinoid and total free sugar.

Time-split Mixing Model for Analysis of 2D Advection-Dispersion in Open Channels (개수로에서 2차원 이송-분산 해석을 위한 시간분리 혼합 모형)

  • Jung, Youngjai;Seo, Il Won
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.33 no.2
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    • pp.495-506
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    • 2013
  • This study developed the Time-split Mixing Model (TMM) which can represent the pollutant mixing process on a three-dimensional open channel through constructing the conceptual model based on Taylor's assumption (1954) that the shear flow dispersion is the result of combination of shear advection and diffusion by turbulence. The developed model splits the 2-D mixing process into longitudinal mixing and transverse mixing, and it represents the 2-D advection-dispersion by the repetitive calculation of concentration separation by the vertical non-uniformity of flow velocity and then vertical mixing by turbulent diffusion sequentially. The simulation results indicated that the proposed model explains the effect of concentration overlapping by boundary walls, and the simulated concentration was in good agreement with the analytical solution of the 2-D advection-dispersion equation in Taylor period (Chatwin, 1970). The proposed model could explain the correlation between hydraulic factors and the dispersion coefficient to provide the physical insight about the dispersion behavior. The longitudinal dispersion coefficient calculated by the TMM varied with the mixing time unlike the constant value suggested by Elder (1959), whereas the transverse dispersion coefficient was similar with the coefficient evaluated by experiments of Sayre and Chang (1968), Fischer et al. (1979).

A Study on the Analysis of Cause and Effect Relationship between Korea Image Attributes and Korea Image Making in Uzbekistan (우즈베키스탄에서의 한국 이미지 속성과 한국 이미지 메이킹의 인과관계 분석)

  • Ryu, Ki-Hwan;Park, Myung-Chan
    • International Commerce and Information Review
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    • v.15 no.1
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    • pp.161-183
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    • 2013
  • The essential purpose of this study is to exemplify empirically some relations of between Korea image attributes and Korea image making in Uzbekistan. This study is for providing basically empirical analysis for intensifying Korea's economic capacity based on Korean image in Uzbekistan and for offering any kinds of implications for the entry and management activities of Korean enterprises in world-wide business. This study is organized in two stages. First, the study model is designed by reappraising relevant theories, previous studies and the current investment qualifications concerning the country image attributes and image making. Second, the survey of Uzbekistan people who are living in South Korea is accomplished by collecting questionnaires. SPSS 15.0 for windows is being activated for correlation, reliability, validity and finally the statistical method of structural equation modeling is utilized to testing the hypothesis by AMOS 7.0 for windows. In conclusion partially, Korea image attributes: economic capability, popular culture, national traits and enterprise competence are proved to influence positively to Korea image making: recognition, attractiveness and confidence which is considered generally by Uzbekistan people.

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The Effects of Family Resilience on the positive attitudes toward a Children with Disabilities and Non-Disabled Siblings (장애아동 가족의 가족탄력성이 장애아동에 대한 비 장애 형제 자매의 긍정적 태도에 미치는 영향)

  • Bae, Seon-Young;Cho, Nam-Ju;Park, Sun-Ja
    • Journal of Digital Convergence
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    • v.11 no.9
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    • pp.239-246
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    • 2013
  • The purpose of this study was to identify the effects of family resilience on the positive attitudes toward a children with disabilities of non-disabled siblings. For this purpose, a survey data was collected from 110 siblings with disabled children. The general characteristics of the parent questionnaire, and the general characteristics of a child with a disability, non-disability sibling's general characteristics, be receptive attitude, consisted of family resilience, and the data were analyzed by frequency analysis, descriptive statistics, t test, ANOVA and regression analysis by SPSS 18.0. Structural equation was used for black AMOS18. The results of the measurement analysis were summarized as follows: 1. family resilience showed positive correlation with positive attitudes toward a children with disabilities of non-disabled siblings. 2. as a result of regression analysis for find out influence of family resilience on the positive attitude of non-disabled siblings, family resilience was statistically significant influence factors, which 50%, 50% explanatory power. In conclusion, these results reinforce the important of considering family context as a contributor to the positive attitudes toward a children with disabilities of non-disabled siblings, so it could be suggested that family resilience needs to be improve.

An analysis on Structure Equation Model of Convergent Influence on Academic Burnout of Health Major Students in Studying for TOEIC (보건계열 대학생의 토익 학업소진에 미치는 융복합적인 요인에 관한 구조방정식 모형 분석)

  • Hong, Soomi;Kim, Seung-Hee;Bae, Sang-Yun
    • Journal of Digital Convergence
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    • v.15 no.7
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    • pp.329-342
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    • 2017
  • This study investigates convergent influence on Self Factors(SF), Stress Factors(STF), Resilience & Control Factors(RCF), Test Anxiety(TA), Learning Flow(LF) and academic burnout among Health College Students in TOEIC class(HCST). The survey was administered to 291 HCST from 1 college located in J area during the period from April 3, 2017 to April 14, 2017. The structured self-administered questionaries were used. With the analysis of covariance structure, we could confirm relationship among the six factors such as SF, STF, RCF, TA, LF and academic burnout. The results of the study indicate that the efforts, to manage these factors, are required to decrease the academic burnout of HCST. Squared multiple correlations, which explain the academic burnout related with the stress from economic pressure and job seeking, test anxiety, learning flow and self factors, were 98.8%. The results are expected to be useful for the development of TOEIC learning curriculum and course to decrease the academic burnout of HCST. In the following study, the analysis about additional factors of influence on academic burnout will be needed.

The Effect of SNS Use by Prospective Early Childhood Teachers in PBL-Based Class on the Flow and Problem-Solving Skills (PBL적용수업에서 예비유아교사의 SNS활용이 플로우(FLOW)와 문제해결력에 미치는 영향)

  • Woo, Kyung Ae;Kim, Se Gon
    • Korean Journal of Childcare and Education
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    • v.10 no.6
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    • pp.165-184
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    • 2014
  • The purpose of this study is to examine the effect of SNS use by prospective early childhood teachers in PBL class on flow and problem-solving skills. For this purpose, the PBL class was conducted for eight weeks with 44 prospective students in the early childhood social studies course, and measured the classroom situation in terms of usefulness of SNS, flow, and problem-solving skills by using a cognitive test. To analyze the measured values, frequency analysis, reliability analysis, factor analysis, and correlation analysis were performed. Also, to verify the hypotheses set in this study, structural equation modeling was used based on AMOS. The result is as follows: First, in PBL-based class, use of SNS had a positive effect on flow. Second, flow had a direct influence on problem-solving skills. Third, however, use of SNS did not have a direct influence on problem-solving skills and, therefore, flow plays a mediating role for problem-solving skills. Based on the result, in the study, it was found that the use of SNS in PBL class can increase interest, motivation, and participation of students and they then become more willing to contribute to class activities.