• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.1215-1218
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• 2009

The goal of this research is to apply the neural networks models for the disaggregation of the pan evaporation (PE) data, Republic of Korea. The neural networks models consist of generalized regression neural networks model (GRNNM) and multilayer perceptron neural networks model (MLP-NNM), respectively. The disaggregation means that the yearly PE data divides into the monthly PE data. And, for the performances of the neural networks models, they are composed of training and test performances, respectively. The training data consist of the mixed data The mixed data involves the historic data and the generated data using PARMA (1,1). And, the testing data consist of the only historic data, respectively. From this research, we evaluate the impact of GRNNM and MLP-NNM for the disaggregation of the nonlinear time series data. We should, furthermore, construct the credible data of the monthly PE data from the disaggregation of the yearly PE data, and can suggest the methodology for the irrigation and drainage networks system.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.1211-1214
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• 2009

The goal of this research is to apply the neural networks models for the disaggregation of the pan evaporation (PE) data, Republic of Korea. The neural networks models consist of generalized regression neural networks model (GRNNM) and multilayer perceptron neural networks model (MLP-NNM), respectively. The disaggregation means that the yearly PE data divides into the monthly PE data. And, for the performances of the neural networks models, they are composed of training and test performances, respectively. The training data consist of the generated data using PARMA (1,1). And, the testing data consist of the historic data, respectively. From this research, we evaluate the impact of GRNNM and MLP-NNM for the disaggregation of the nonlinear time series data. We should, furthermore, construct the credible data of the monthly PE data from the disaggregation of the yearly PE data, and can suggest the methodology for the irrigation and drainage networks system.

• Journal of Korean Society for Quality Management
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• v.24 no.4
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• pp.29-43
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• 1996

This paper identifies these data by the data diagnosis in lognormal distribution and presents the method to obtain exact parameter estimates and confidence intervals of regression line. The life-stress relationship uses Arrhenius model and life data generate Class-H insulation complete data by simulation. Also, the method to estimate parameters uses least squares estimation and externally Studentized residuals can be used as test statistics for identifing outliers. And influential cases are identified by Cook's distance. This research is intended to obtain the useful information for the life of products and test method, to save time and costs, and to help optimum accelerated life test plans.

• Korean Management Science Review
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• v.33 no.3
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• pp.105-117
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• 2016

In this paper, we present empirical testing result to examine the validity of inbound supply and outbound demand risk factors in the sense of early predicting the firm's bankruptcy risk level. The risk factors are drawn from industry uncertainty attributes categorized as uncertainties of input market (inbound supply), and product market (outbound demand). On the basis of input-output table, industry level inbound and outbound sectors are identified to formalize supply chain structures, relevant inbound and outbound uncertainty attributes and corresponding risk factors. Subsequently, publicly available macro-economic indicators are used to appropriately quantify these risk factors. Total 68 industry level bankruptcy risk forecasting results are presented with the average R-square scores of between 53.4% and 37.1% with varying time lag. The findings offers useful insights to incorporate supply chain risk to the body of firm's bankruptcy risk level prediction literature.

• Korean Journal of Child Studies
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• v.31 no.1
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• pp.113-124
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• 2010

This study analyzed the relationships between home environment, child characteristics and school readiness. In particular, it examined the influence of home environment and child characteristics upon children's school readiness with a focus on attitudes towards and other socio-emotional aspects. 57 children's characteristics, including such items as IQ performance and demographic variables were obtained by means of both individual testing of the child and through a questionnaire given to their parents. Relative levels of school readiness were then rated by teachers. Pearson correlations, and a multiple regression analysis were carried out using the SPSS Win 12.0 program. Our results indicated that (1) school readiness was positively related with mother's job, HOME, the ages of the children, Performance IQ, and Total IQ. (2) The level of the other's education, her job and the child's age was found to significantly predict the level of school readiness.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.697-702
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• 1999

Among several non-destructive testing methods, ultrasonic pulse velocity method has been widely used for the evaluation of concrete strength. However, this method might not provide accurate estimated results since factors influencing the relationship between strength and wave velocity is not considered. In this study, the evaluation methods of concrete strength using compression wave velocities measured by either ultrasonic pulse velocity method or impact-resonance method are proposed. A basic equation is obtained by the linear regression with velocity vs. strength data at a specific age and then, ageing factor is employed in the equation to consider the difference of the increasing rate between wave velocity and strength. Strengths predicted by the proposed equation agree well with test results.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.4
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• pp.591-595
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• 2002

Three hundred thirty five progeny testing steers of Korean beef cattle were evaluated ultrasonically for back fat thickness (BFT), longissimus muscle area (LMA) and intramuscular fat (IF) before slaughter. Class measurements associated with the Korean yield grade and quality grade were also obtained. Residual standard deviation between ultrasonic estimates and carcass measurements of BFT, LMA were 1.49 mm and $0.96cm^2$. The linear correlation coefficients (p<0.01) between ultrasonic estimates and carcass measurements of BFT, LMA and IF were 0.75, 0.57 and 0.67, respectively. Results for improving predictions of yield grade by four methods-the Korean yield grade index equation, fat depth alone, regression and decision tree methods were 75.4%, 79.6%, 64.3% and 81.4%, respectively. We conclude that the decision tree method can easily predict yield grade and is also useful for increasing prediction accuracy rate.

• International Journal of Contents
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• v.5 no.4
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• pp.19-29
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• 2009

This study is focused on the causal relationship between children's intimate behavior and the level of perception towards their grandparents. Their perceptions are related to factors such as proximity, similarity, superiority, favorableness, and self-disclosure. We clarified the relation between intimate behavior and perception using effect factors of children's behavior regarding their grandparents so that this study could be used as an elementary material in developing a solution to improve grandparent-grandchild relationship where the grandparent actively encourages grandchildren's intimate behavior. Regression analysis was used as a hypothesis testing method. The results indicated the following three points. First, perception factors affect active intimate behavior in the order of favorableness, superiority, self-disclosure, and similarity. Second, perception factors affect intimate behavior will in the order of favorableness, superiority, and self-disclosure. Lastly, it was shown that a child's active intimate behavior has an influence on their intimate behavior will.

• Communications for Statistical Applications and Methods
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• v.8 no.1
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• pp.127-135
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• 2001

In this paper, we consider a simple method for testing the assumption of independent censoring on the basis of a Cox proportional hazards regression model with a time-dependent covariate. This method involves a two-stage sampling in which a random subset of censored observations is selected and followed-up until their true survival times are observed. Lee and Wolfe(1998) proposed an adjusted estimate of the survivor function for the dependent censoring under a proportional hazards alternative. This paper extends their result to obtain a bootstrap confidence interval for the adjusted survivor function under the dependent censoring. The proposed procedure is illustrated with an example of a clinical trial for lung cancer analysed in Lee and Wolfe(1998).

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.2
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• pp.228-236
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• 2001

Economic crisis in Korea since December 1997 had tremendously affected consumer behavior. This study examined consumer perception of the economic crisis and investigated its impacts on consumer ethnocentrism and purchase behaviors of foreign products. Two product categories of clothing and cosmetics were selected fro empirical testing. Data were obtained from a questionnaire survey to female consumers in Korea during September 1998, and 468 responses were analyzed. The consumer perception of the economic crisis(PCEP) scale was developed for the study. Correlation and regression analyses revealed: 1) the positive relationship between PCEP and consumer ethnocentrism(ETHN); 2) the positive effects of attitude toward foreign products(ATTI) on actual purchase of foreign products since the economic crisis(PB) and on purchase intention of foreign products(PI) for both clothing and cosmetics; 3) the negative effect of ETHN on PI for both product categories; and 4) the negative effects of PCEP on PB and PI for clothing.