• 제목/요약/키워드: Independent Variables

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A Study on Weight Estimation Model of Floating Offshore Structures using Enhanced Genetic Programming Method (개선된 유전적 프로그래밍 방법을 이용한 부유식 해양 구조물의 중량 추정 모델 연구)

  • Um, Tae-Sub;Roh, Myung-Il;Shin, Hyunkyoung
    • Journal of the Society of Naval Architects of Korea
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    • v.52 no.1
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    • pp.1-7
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    • 2015
  • The weight estimation of floating offshore structures such as FPSO, TLP, semi-Submersibles, Floating Offshore Wind Turbines etc. in the preliminary design, is one of direct measures of both construction cost and basic performance. Through both literature investigation and internet search, the weight data of floating offshore structures such as FPSO and TLP was collected. In this study, the weight estimation model with the genetic programming was suggested for FPSO. The weight estimation model using genetic programming was established by fixing the independent variables based on this data. In addition, the correlation analysis was performed to make up for the weak points of genetic programming; it is apt to induce over-fitting when the number of data is relatively smaller than that of independent variables. That is, by reducing the number of variables through the analysis of the correlation between the independent variables, the increasing effect in the number of weight data can be expected. The reliability of the developed weight estimation model was within 2% of error rate.

A Study on the Determinants of Pro-Environmental Attitude and Water Consumption of Urban Households (도시 가구의 환경 친화적인 태도와 물 소비에 관한 연구)

  • 이경희
    • Journal of the Korean Home Economics Association
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    • v.41 no.3
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    • pp.93-111
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    • 2003
  • This study aimed to examine the water consumption of urban households according to pro-environmental attitude for environmental protection. In contrast to preview studies, this study purposed to include various related independent variables, motive to environmental behavior, in special, in the model, and suggest informative data for research, education and strategies related to environmental protection. The data were from 665 housewives living in five urban areas. For the analysis of data, frequencies, means, percentages, GLM analysis, DMR test and Chi-square test were used. The main results of this study were as follows; 1. The respondents held high pro-environmental attitude that pro-environmental behaviors are important to protect environment. The pro-environmental attitude among the respondents were statistically different from the independent variables : spouse's occupation, living area, help of housekeeper, knowledge about environmental protection, convenience to check water consumption, and perception of voluntary conservative behavior among neighborhood 2. There were great difference on water consumption among respondents. The significant independent variables to have effects on water consumption were different between water consumption per person and higher/lower average water consumption. The relationships of pro-environmental attitude and motive to pro-environmental behavior with two water consumption as dependent variables were unique. Also, living areas and knowledge about environment protection were consistently important to explain the difference of water consumption.

The Effect of Teacher-Infant Interaction and the Multiple Mediation of Classroom Environment on the Effect of Infant Teacher Expertise, Teaching Creativity, and Play Beliefs on Play Teaching Efficacy (영유아 교사의 전문성, 교수창의성, 놀이신념이 놀이교수효능감에 미치는 영향에 있어 교사-영유아 상호작용과 교실환경의 다중매개효과)

  • Lee, Misun;Hwang, Hye Jung
    • Human Ecology Research
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    • v.60 no.1
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    • pp.87-98
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    • 2022
  • This study examined the relationships between teacher variables that improve the efficacy of the play teaching of infants and toddlers following a play-oriented curriculum. The participants were 287 infant teachers. The results were as follows. First, the independent variables had a significant effect on the efficacy of play teaching, teacher-infant interaction, and classroom environment. Second, the mediating effects of teacher-infant interaction and classroom environment on the effect of independent variables on the efficacy of play teaching were as follows. The interaction mediating effect between professionalism and play belief was significant, but teaching creativity was found to be significant. In the mediating effect of the classroom environment, expertise, play belief, and teaching creativity were found to be significant. Third, both teacher-infant interaction and the multimedia effect of the classroom environment were statistically significant in mediating the effect of independent variables on the efficacy of play teaching. These results provide basic data on the necessity for teacher education to explore ways to improve teachers' sense of efficacy in teaching play and their teaching skills.

Screening Vital Few Variables and Development of Logistic Regression Model on a Large Data Set (대용량 자료에서 핵심적인 소수의 변수들의 선별과 로지스틱 회귀 모형의 전개)

  • Lim, Yong-B.;Cho, J.;Um, Kyung-A;Lee, Sun-Ah
    • Journal of Korean Society for Quality Management
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    • v.34 no.2
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    • pp.129-135
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    • 2006
  • In the advance of computer technology, it is possible to keep all the related informations for monitoring equipments in control and huge amount of real time manufacturing data in a data base. Thus, the statistical analysis of large data sets with hundreds of thousands observations and hundred of independent variables whose some of values are missing at many observations is needed even though it is a formidable computational task. A tree structured approach to classification is capable of screening important independent variables and their interactions. In a Six Sigma project handling large amount of manufacturing data, one of the goals is to screen vital few variables among trivial many variables. In this paper we have reviewed and summarized CART, C4.5 and CHAID algorithms and proposed a simple method of screening vital few variables by selecting common variables screened by all the three algorithms. Also how to develop a logistics regression model on a large data set is discussed and illustrated through a large finance data set collected by a credit bureau for th purpose of predicting the bankruptcy of the company.

The Relationship between Social Competency of the Child and the Child Rearing Involvement of the Father (아버지의 양육 참여도와 아동의 사회적 능력과의 관계)

  • Choi, Kyung Soon
    • Korean Journal of Child Studies
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    • v.14 no.2
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    • pp.115-135
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    • 1993
  • The purpose of this study was to develop instruments for measuring paternal child rearing involvement. A second purpose was to investigate the relationship between social competency of child and the father's involvement in child rearing. Fathers' child rearing involvement inventories were administered to 513 5th and 6th grade school students to evaluate children's perceived father's rearing involvement. Assessment of the child's social competency by the mother was by the modified Iowa Social Competency Scale. Data were analyzed by factor analysis, Pearson's correlation coefficient, and canonical correlation. The main results were as follows: (1) There were differences in mean scores between variables on father's child rearing involvement. The mean score of 'day-to-day guidance' was higher than such father's involvement variables as 'family activities', 'household affairs', 'home education'. (2) There was a significant correlation between the social competency of children and father's child rearing involvement. In other words, fathers' child rearing involvement showed significant correlations with 'the capability' and 'leadership' of children. (3) The canonical analysis in two variables-the fathers' child rearing involvement (independent variables) and the children's social competency (dependent variables)-showed that the child variables most highly correlated to the independent variables were 'capability' and 'affection toward parents'. This also indicated that the father variables accounted for about 9.4% of the variation in social competency. In conclusion, the father's child rearing involvement can he recognized as significant variable in predicting the social competency of children.

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The Processing Optimization of Caviar Analogs Encapsulated by Calcium-Alginate Gel Membranes

  • Ji, Cheong-Il;Cho, Sueng-Mock;Gu, Yeun-Suk;Kim, Seon-Bong
    • Food Science and Biotechnology
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    • v.16 no.4
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    • pp.557-564
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    • 2007
  • We prepared caviar analogs encapsulated by calcium-alginate gel membranes as a means to replace higher priced natural caviars. Processing the caviar analogs (beluga type) was optimized by response surface methodology with central composite design. Concentrations of sodium alginate ($X_1$) and $CaCl_2\;(X_2)$ were chosen as the independent variables. In order to compare characteristics of the caviar analogs with the natural caviar, sphericity ($Y_1$), diameter ($Y_2$), membrane thickness ($Y_3$), rupture strength ($Y_4$), rupturing deformation ($Y_5$), and sensory score ($Y_6$) were used as the dependent variables. The sphericity of the caviar analogs showed a similar value to that of natural caviar (over 94%) in the range of independent variables. Generally, the $CaCl_2$ concentration ($X_2$) affected all dependent variables to a greater extent than the sodium alginate concentration ($X_l$), For the multiple response optimization of the 5 dependent variables ($Y_1,\;Y_2,\;Y_4,\;Y_5$, and $Y_6$), the desirability function was defined as the following conditions: target values ($Y_1\;=\;100%,\;Y_2\;=\;3.0\;mm,\;Y_4\;=\;1,470\;g,\;Y_5\;=\;1.1\;mm,\;and\;Y_6\;=\;10\;points$). Membrane thickness ($Y_3$) was eliminated from the dependent variables for multiple response optimization because it could not be measured with an image analyzer. The values of the independent variables as evaluated by multiple response optimization were $X_1\;=\;-0.093$ (78%) and $X_2\;=\;-0.322$ (1.07%), respectively.

Performance Improvement of General Regression Neural Network Using Principal Component Analysis (주요성분분석에 의한 일반회귀 신경망의 성능개선)

  • Cho, Yong-Hyun
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.11
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    • pp.3408-3416
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    • 2000
  • This paper proposes an efficient method for improving the performance of a general regression neural network by using the feature to the independent variables as the center for partern-layer neurons. The adaptive principal component analysis is applied for extracting, efficiently the fcarures by reducing the dimension of given independent variables. In can acluevc a supertor property of the principal component analysis that converts input data into set of statistically independent features and the general regression neuralnetwork, espedtively. The proposed general regression neural network has been applied to regress the Solow's economy(2-independent variable set) and the wie elephone(1-independent vanable set). The simulation results show that the proposed meural networks have better performances of the regressionfor the lest data, in comparison with those using the means or the weighted means of independent variables. Also,it is affected less by the number of neurons and the scope of the smoothing factor.

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Estimating the reliability and distribution of ratio in two independent variables with different distributions

  • Yun, Sang-Un;Lee, Chang-Soo
    • Journal of the Korean Data and Information Science Society
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    • v.23 no.5
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    • pp.1017-1025
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    • 2012
  • We consider estimations for the reliability in two independent variables with Pareto and uniform or exponential distributions. And then we compare the mean squared errors of two reliability estimators for each case. We also observe the skewness of densities of the ratio for each case.

A tightness theorem for product partial sum processes indexed by sets

  • Hong, Dug-Hun;Kwon, Joong-Sung
    • Journal of the Korean Mathematical Society
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    • v.32 no.1
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    • pp.141-149
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    • 1995
  • Let N denote the set of positive integers. Fix $d_1, d_2 \in N with d = d_1 + d_2$. Let X and Y be real random variables and let ${X_i : i \in N^d_1} and {Y_j : j \in N^d_2}$ be independent families of independent identically distributed random variables with $L(X) = L(X_i) and L(Y) = L(Y_j)$, where $L(\cdot)$ denote the law of $\cdot$.

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