• Journal of the Korean Institute of Gas
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• v.1 no.1
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• pp.7-13
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• 1997

To investigate the pressure dependence of minimum ignition energy(MIE), thermal ignition theory, concept of heat transfer, ideal gas law, and kinetic theory are discussed. Correlation equations for the MIE and pressure were obtained through a regression analysis of reported data. In the proposed methodology the predicted MIE with pressure variations agree with reported data within a few average absolute deviations(A.A.D.). Therefore the proposed methodology has provided to be the general method for predicting the MIE of hydrocarbons.

• Progress in Superconductivity
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• v.10 no.2
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• pp.149-154
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• 2009

We measured and analyzed the quench development in coated conductor(CC) tapes. The CC was grown on hastelloy substrates and has an Ag protection layer. The tapes were subjected to simulated AC fault currents for quench development measurement. They were immersed in liquid nitrogen during the experiment. The quench resistance increased rapidly first, and the increase slowed down afterwards. It increased linearly with applied voltage at lower voltages, and depended less strongly on applied voltage at higher voltages. The resistance was compared with that of Au/YBCO films grown on sapphire substrates, and found to increase more monotonously than the latter. Data were analyzed quantitatively with the concept of heat transfer within the tape and the surrounding liquid nitrogen. A heat balance equation was derived and solved, taking into consideration temperature dependence of thermal parameters of the tapes. Solutions, together with values of thermal parameters taken from the literature, explained the data well. Cooling by liquid nitrogen affected the quench development considerably at lower applied voltages. Dependence on applied voltages could be also understood quantitatively.

• The Korean Journal of Applied Statistics
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• v.24 no.5
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• pp.809-820
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• 2011

VaR(Value at risk) is a measure of market risk management and needs to be estimated for multiple distributions. In this paper, Copula functions are used to generate distributions of multivariate random variables. The dependence structure of random variables is classified by the exchangeable Copula, fully nested Copula, partially nested Copula. For the earning rate data of four Korean industries, the parameters of the Archimedean Copula functions including Clayton, Gumbel and Frank Copula are estimated by using three kinds of dependence structure. These Copula functions are then fitted to to the data so that corresponding VaR are obtained and explored.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.103-103
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• 2010

Dependence of radical and ion densities on Plasma Parameters is theoretically investigated in $Cl_2$/Ar plasma discharges. Firstly, a set of reliable rate coefficients is obtained by direct calculations with cross section data set and by comparing them with previously reported values. Then, some global discharge simulations are performed for ICP(inductively coupled plasma) discharges and the results are compared with experimental results. Finally, the validated data set is used to analyze the dependence of radical and ion densities, which are usually not easy to be measured, on electron density arid temperature.

• The Journal of Korean Academic Society of Nursing Education
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• v.10 no.2
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• pp.229-238
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• 2004

This study was conducted to identify the factors affecting smoking cessation behavior of the university student smokers for developing the effective smoking cessation program. For this purpose, data were collected from 64 students registrated at the university health center for anti-smoking acupuncture through May, 2003. Data were analyzed with percentile, mean, t-test, ANOVA, pearson correlation by SPSS/PC program. The results were as follows ; There was significant relationship in the scores on perceived benefits(t=-2.05, p=.045), chance-health locus of control(t=-2.28, p=.026) and nicotine dependence (t=-1.96, p=.056) according to the grade. And also there was significant increase in the nicotine dependence in the higher grades. There were significant positive relationship between external locus of control and perceived benefits(r=.389, p=.001), perceived barriers and benefits(r=.457, p=.000), and significant negative relationship between the daily life activities and perceived barriers(r=-.350, p=.005). From these results, it can be concluded that the effective smoking cessation program could be considered of perceived benefits & barriers, and nicotine dependence to promote anti-smoking behavior for university student smokers.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1285-1288
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• 2012

Background: The Fagerstrom Test for Cigarette Dependence (FTCD) (formally FTND) is widely used for measuring physical dependence on nicotine. Objective: To explore the cross cultural validity and reliability of FTCD amongst Arabic speaker cigarette consumers who chew khat leaf, a stimulant green leaf. Methods: The psychometric properties of the FTCD were assessed in a subsample (91regular cigarette smokers) of purposively selected 204 UK-resident Yemeni khat chewers recruited during random visits to khat sale outlets. Data were collected via a structured face-to-face interview. Data analyses included descriptive tests and factor analysis. Results: Two factors were obtained by a principle axis factor analysis and these were termed as urgency of restoring the level of nicotine after abstinence during sleeping and maintaining the level of nicotine during waking. The internal reliability (Cronbach's alpha coefficient) of the whole FTCD is low (.68) as well as for the two subscales (.60) and (.62) respectively. Conclusion: The psychometric properties of the Arabic version of the FTCD scale in this sample of Yemeni khat chewers who smoked regularly confirmed what has been established in other cultural settings. The findings of this study have yet to be cross validated amongst other appropriately representative sample of Arabic speakers.

• Journal of the Korean Institute of Gas
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• v.15 no.2
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• pp.75-81
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• 2011

For the safe handling of cyclohexane, the explosion limit at $25^{\circ}C$ and the temperature dependence of the explosion limits were investigated. Flash point and AIT(autoignition temperature) for cyclohexane were experimented. By using the literatures data, the lower and upper explosion limits of cyclohexane recommended 1.0 Vol% and 9.0 Vol%, respectively. Moreover lower flash points of cyclohexane recommended $-20^{\circ}C$. It was measured relationship between the AITs and the ignition delay times by using ASTM E659-78 apparatus for cyclohexane, and the experimental AIT was $255^{\circ}C$. The new equations for predicting the temperature dependence of the explosion limits of cyclohexane is proposed. The values calculated by the proposed equations were a good agreement with the literature data.

• Journal of Microbiology
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• v.43 no.5
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• pp.411-416
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• 2005

The high-throughput sequencing of microbial genomes has resulted in the relatively rapid accumulation of an enormous amount of genomic sequence data. In this context, the problem posed by the detection of promoters in genomic DNA sequences via computational methods has attracted considerable research attention in recent years. This paper addresses the development of a predictive model, known as the dependence decomposition weight matrix model (DDWMM), which was designed to detect the core promoter region, including the -10 region and the transcription start sites (TSSs), in prokaryotic genomic DNA sequences. This is an issue of some importance with regard to genome annotation efforts. Our predictive model captures the most significant dependencies between positions (allowing for non­adjacent as well as adjacent dependencies) via the maximal dependence decomposition (MDD) procedure, which iteratively decomposes data sets into subsets, based on the significant dependence between positions in the promoter region to be modeled. Such dependencies may be intimately related to biological and structural concerns, since promoter elements are present in a variety of combinations, which are separated by various distances. In this respect, the DDWMM may prove to be appropriate with regard to the detection of core promoter regions and TSSs in long microbial genomic contigs. In order to demonstrate the effectiveness of our predictive model, we applied 10-fold cross-validation experiments on the 607 experimentally-verified promoter sequences, which evidenced good performance in terms of sensitivity.

• Korean Journal of Child Studies
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• v.14 no.1
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• pp.77-89
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• 1993

The purpose of this study was to investigate (1) children's field dependence by age and sex, (2) children's interpersonal problem solving ability by age, sex, and contextual factors, (3) children's interpersonal problem solving ability by field dependence. The subjects were 120 five-, seven-, and nine-year-olds. Children's field-dependence was measured with the Children's Embedded Figures Test (CEFT). Children's interpersonal problem solving ability was measured with the Preschool Interpersonal Problem Solving Test (PIPS Test). Statistical methods adopted for data analysis were frequencies, percentiles, means, standard deviation, t-test, oneway ANOVA. $Scheff{\acute{e}}$ test and Pearson's correlations. Major findings were that (1) The older children were more field-independent than the younger ones (2) The older children suggested more problem solving methods and higher-level problem solving strategies than the younger ones. (3) Children suggested higher-level problem solving strategies in contexts involving familiar as opposed to unfamiliar participants and contexts involving children as opposed to adults. (4) 9-year-olds' field-independence was positively associated with interpersonal problem solving ability.

• Transactions of the Korean Society of Automotive Engineers
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• v.4 no.5
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• pp.206-214
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• 1996

Because of the wide variety of the composite materials, inherent variability in properties, and complex temperature and strain rate dependence, large strain behavior of these materials has not been well characterized. Large strain behavior under uniaxial tension is characterized over a range of temperatures and strain rates, and a modified simple linear viscoelastic model is fit to the observed data. Of particular importance is the strain rate and temperature dependence of these composites, and it is the primary focus of this study. The strain rate and temperature dependence is then used to predict limiting tensile strains, based on Marciniak imperfection theory. Excellent correlation was obtained between model and experiment and the results are summarized in maps of forming limit as a function of strain rate and temperature.