• Journal of the Korean Data and Information Science Society
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• v.18 no.2
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• pp.553-560
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• 2007

In this paper, we consider two components system which lifetimes have Freund's bivariate exponential model with equal failure rates. We propose Bayesian multiple comparisons procedure for the failure rates of I Freund's bivariate exponential populations based on Dirichlet process priors(DPP). The family of DPP is applied in the form of baseline prior and likelihood combination to provide the comparisons. Computation of the posterior probabilities of all possible hypotheses are carried out through Markov Chain Monte Carlo(MCMC) method, namely, Gibbs sampling, due to the intractability of analytic evaluation. The whole process of multiple comparisons problem for the failure rates of bivariate exponential populations is illustrated through a numerical example.

• 한국데이터정보과학회:학술대회논문집
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• 2006.11a
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• pp.71-80
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• 2006

A nonparametric Bayesian multiple comparisons problem (MCP) for dependence parameters in I bivariate exponential populations is studied here. A simple method for pairwise comparisons of these parameters is also suggested. Here we extend the methodology studied by Gopalan and Berry (1998) using Dirichlet process priors. The family of Dirichlet process priors is applied in the form of baseline prior and likelihood combination to provide the comparisons. Computation of the posterior probabilities of all possible hypotheses are carried out through Markov Chain Monte Carlo method, namely, Gibbs sampling, due to the intractability of analytic evaluation. The whole process of MCP for the dependent parameters of bivariate exponential populations is illustrated through a numerical example.

• Communications for Statistical Applications and Methods
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• v.3 no.2
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• pp.187-195
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• 1996

This paper deals with the stochastic comparisons of order statistics from independent but nonidentically distributed (i.n.i.d) variates. And we consider order statistics under positive dependence, negative dependence, and exchangeability.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.148-151
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• 2002

To clarify of chemical contents for the Keumsan ginseng, two attempts have been done for two year: 2 year and 4 year-ginsengs coilected from the phyllite(Ph0 and granite area(Gr), and 1 year, 2 year and 3 year-ginsengs collected from the phyllite(Ph), shale(Sh) and granite (Gr), In the first attempt, the soil contents of the Ph are high in most of elements. In the comparisons between ages of the ginseng, regardless the area, most of the elements are high in the 4 year and these trends are distinctive in the granite area. In the comparisons of the areas, 2 year-ginsengs of the Ph show high contents in the most of the elements. Comparisons between upper part(leaf and branch) and root part of the ginsengs show that in the 2 year-ginseng, the Gr is high in the root part and the Ph is high in the upper part, while in the 4 year-ginseng, most of the elements are high in the root part. Comparisons between contents of soil and ginsengs show similar in crease and decrese trends. However, the 2 year-ginsengs show clear differences between two areas while in the 4 year-ginseng, differences between the Gr and Ph is not clear. It suggest that the ginsengs absorb eligible element contents with ages, despite of clear content differences of the different soils. In the second attempt, the Gr shows high W, Pb, Th, U, Sn and B contents wlile Ph and Sh show high Ni, Cr, Co, Sc, V, As, Cu and Zn contents. In the comparisons between ages of the ginseng, regardless the area, most of the elements are high in the 2 year, especially in the Gr and Ph. In the comparisons of the areas, 2 year-ginsengs of the Gr show low contents in the most of the elements, and the S1 show higher Ni, V, Th and U contents than the Ph. 3 year-ginsengs of the Gr show low contents in the most of the elements, while the S1 show high contents in the most of elements. relative to the Ph. Comparisons between upper part and root part of the ginsengs show that in the ginseng, regardless the ages, the upper part is high. Comparisons between contents of soil and ginsengs show similar increase and decrese trends, and soil is low than the ginsengs in the most of the elements

• Proceedings of the Korean Reliability Society Conference
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• 2002.06a
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• pp.411-414
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• 2002

A class of block designs for general combining ability comparisons within two groups of inbred lines in diallel crosses is given. Use is made of balanced block designs obtained by cyclically developing a single initial block.

• Asian Journal for Public Opinion Research
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• v.11 no.1
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• pp.4-30
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• 2023

Previous research has empirically demonstrated the negative effects of social media use on young people's psychological well-being. Unlike most previous studies that focused on either Facebook or Instagram, this study comparatively examined the differences in upward comparison and its effects on self-esteem, life satisfaction, and depression between Facebook and Instagram. An analysis of survey data from 641 Korean college students, who reportedly use these two social media more actively than any other age group, found that college students experience more upward comparisons on Instagram than on Facebook. Upward comparisons on both Facebook and Instagram increased by college students' age and weekly usage time. Upward comparisons on Instagram increased by the additional factors of gender (females more than males) and number of "followings." Subsequently, the effects of upward comparison on psychological well-being were found to differ by social media platform. Upward comparisons were found to negatively impact all determinants of psychological well-being only on Instagram, but not on Facebook. The differences in upward comparison and its impact on young users' psychological well-being found in this study were discussed in terms of the different functional characteristics of the two social media platforms, which provides direction for further research needed to establish guidelines for healthy social media use by young people.

• Proceedings of the Korean Statistical Society Conference
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• 2002.05a
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• pp.165-170
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• 2002

Sometimes we have two groups of inbred lines and there are only interest in gca comparisons within group($p_{1}$) and group($p_{2}$) and not between two groups. For example, suppose there two Lab, each of the 2 Labs have obtained the best lines. For this purpose we now give a method of constructing block designs for diallel cross experiments and we will explain how to calculate efficiency. Then we show the efficiencies in the table.

• Journal of the Korean Data and Information Science Society
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• v.17 no.2
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• pp.569-579
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• 2006

Recently, the amount of genome sequence is increasing rapidly due to advanced computational techniques and experimental tools in the biological area. Sequence comparisons are very useful operations to predict the functions of the genes or proteins. However, it takes too much time to compare long sequence data and there are many research results for fast sequence comparisons. In this paper, we propose a hybrid grid system to improve the performance of the sequence comparisons based on the LanLinux system. Compared with conventional approaches, hybrid grid is easy to construct, maintain, and manage because there is no need to install SWs for every node. As a real experiment, we constructed an orthologous database for 89 prokaryotes just in a week under hybrid grid; note that it requires 33 weeks on a single computer.

• Journal of KSNVE
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• v.7 no.6
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• pp.1049-1058
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• 1997

To verify the Finite Element Method(FEM) model of an Exhaust System, Frequency Response Function(FRF) is utilized. Up to now, generally, comparisons of natural frequencies and mode shapes of the Exhaust System between numerical analysis and experimental results are adopted to prove completion of the FEM model. However, the comparisons of natural frequencies and mode shapes are not sufficient to have the perfect FEM model of the Exhaust system. Instead of these comparisons. FRF method is introduced for the more accurate FEM model.

• STI Policy Review
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• v.6 no.2
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• pp.146-173
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• 2015

This study explores how to reconcile science and policy in the wind energy sector by providing a conceptual framework for better understanding evidence-based policymaking (EBPM). Regarding this framework, the core issue is to discover how knowledge is formed over time, and which factors affect this knowledge formation. Comparative cases of wind industry emergence in Spain and Britain are examined. This analysis shows that knowledge formation initially starts in the scientific arena in parallel with its formation in the practical, and is followed by political knowledge formation near the beginning of commercial projects. Regarding knowledge formation, three more comparisons are made between wind industry emergence in Spain and Britain: the different approaches to R&D projects, the different adoptions of supporting measures, and the different ways of coping with public opposition. The factors affecting the comparisons are mainly perceptions of energy supply, nuclear power, environment and science and technology. Communication and unfamiliarity are likely to affect the comparisons in EBPM.