• The Korean Journal of Applied Statistics
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• v.26 no.6
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• pp.933-942
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• 2013

Common factor analysis and principal component analysis represent two technically distinctive approaches to exploratory factor analysis. Much of the psychometric literature recommends the use of common factor analysis instead of principal component analysis. Nonetheless, factor analysts use principal component analysis more frequently because they believe that principal component analysis could yield (relatively) less accurate estimates of factor loadings compared to common factor analysis but most often produce similar pattern of factor loadings, leading to essentially the same factor interpretations. A simulation study is conducted to evaluate the relative performance of these two approaches in terms of factor pattern recovery under different experimental conditions of sample size, overdetermination, and communality.The results show that principal component analysis performs better in factor recovery with small sample sizes (below 200). It was further shown that this tendency is more prominent when there are a small number of variables per factor. The present results are of practical use for factor analysts in the field of marketing and the social sciences.

• Korean Journal of Culture and Social Issue
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• v.26 no.3
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• pp.259-282
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• 2020

This study examines the validity of the Filial Responsibility Scale-Adult (Past), developed by Jurkovic and Thirkield (1999), among Korean university students in their twenties. First, a preliminary scale consisting of 30 items was developed by translating the original scale into Korean and item analysis and exploratory factor analysis were conducted on 249 subjects. Based on the exploratory factor analysis, items in the emotional parentification factor were either deleted or included in the other remaining factors, resulting in a two-factor model containing 15 items. In order to confirm this, a confirmatory factor analysis was conducted on 318 independent subjects. As a result of a confirmatory factor analysis of the two competing models - the three-factor model consisting of 30 items based on the original scale and the two-factor(emotional experience and caring behavior) model consisting of 15 items gained as a result of the exploratory factor analysis - the two-factor model showed more suitable and the original scale was revised accordingly. The convergent validity, discriminant validity and predictive validity were all found to be satisfactory. Based on such results, implications, limitations and suggestions on follow-up studies are discussed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.7
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• pp.571-577
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• 2006

The characteristics of ice packing factor (IPF) at the ice slurry system using one line type are compared with the system using two lines type. The installation space for one transporting line is saved at the one line system. For the one line type, the ice packing factor is reduced along the downstream, but for the two lines type, the ice packing factor is fixed. For the one line system, mass flow rate in the main line is fixed along the down-stream, but for two lines system, the mass flow rate in the main line is reduced along the downstream. For one line system, along the down stream after IPF=0, the temperature at the main steam is increased, and the extracted mass flow is increased. The initial IPF, at which the IPF is not arrived at zero upto the final node, is proposed for the B area.

• International Journal of Human Ecology
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• v.11 no.1
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• pp.1-10
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• 2010

Two elements of paisley textile design (color and size of motif) were manipulated to investigate their effects on people's perception. Korean and Caucasian American women were selected to represent Asian and Western countries to compare the differences in image perceptions of paisley patterns between two cultures. The participants were 168 female university students composed of 84 Caucasian Americans and 84 Koreans. The experimental design was a $2{\times}2{\times}7$ factorial design: two levels of perceiver's culture, two levels of motif size, and seven levels of the motif color. The four factors used to account for image perception were an elegance factor, individuality factor, maturity factor, and femininity factor. The results of the present study confirm that image perception can be different according to the color and size of a motif and the perceiver's culture. In the results, Americans perceived the paisley pattern as more preferable than Koreans did. Red background + Orange motif was perceived as the most feminine and Dark blue background + Sky blue motif and Dark gray background + Gray motif was perceived as the most masculine in both cultures. Compared to the big motif, the small motif was perceived as more elegant in both cultures.

• Anxiety and mood
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• v.13 no.2
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• pp.86-92
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• 2017

Objective : This study evaluated the factor structure of a Korean version of the Penn State Worry Questionnaire (K-PSWQ) with exploratory factor analysis in healthy adult subjects, and confirmatory factor analysis of subjects who have received psychiatric treatment. Methods : Exploratory principal component analysis was conducted with data from 318 non-psychiatric subjects, and 118 psychiatric patients were subjected to confirmatory factor analysis (maximum likelihood estimation). Participants were voluntary visitors at the booth who agreed to undergo screening for anxiety disorder at 2013 & 2014 Korea Mental Health Exhibitions. Results : Exploratory analysis revealed a two factor structure of the scale with total variance of 56.3%. Factor 1 was considered 'Worry engagement', and factor 2 was considered 'Absence of worry'. However, the results of the confirmatory factor analysis supported that both one factor model with method factor and two factor model are fit to structure of the scale considering fit indices. Internal consistency of total questions was good (Cronbach's ${\alpha}=0.899$). Conclusion : Our results supported the previously suggested factor structure of the PSWQ, and proved factorial validity of the K-PSWQ in both populations.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.9C
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• pp.889-896
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• 2006

The crest factor distribution of orthogonal frequency division multiplexing (OFDM) symbol sequences is evaluated and it is shown that OFDM symbol sequences with a short period are expected to have a high crest factor. The crest factor relationship between two input symbol sequences, Hamming distance D apart is also derived. Using these two results, we propose two criteria for a phase sequence set of the selected mapping (SLM) scheme and suggest the rows of the cyclic Hadamard matrix constructed from an m-sequence as the near optimal phase sequence set of the SLM scheme.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.5
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• pp.146-152
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• 2007

Recently, The air pollution problems become hot issues as the production of the diesel automotive increases. The ministry of environment has enforced a precise inspection law to decrease the vehicle emission. In this circumstances, the smoke measurement is somewhat complicated by the use of the different type smoke meters. Although the paper filtration type opacimeter has been used for measuring smoke widely but currently the light extinction type is being used for precise inspection law. These two type opacimeters are different in their measuring principles on each other. So, for the time being the regulation standards can be confused by these two type opacimeters. In this article, The correlation factor between these two type opacimeters is studied by using engine dynamometer and vehicle test. The result of the dynamometer test shows the light extinction type is more sensitive than the filtration type by 1.47 times. But the relation factor by the vehicle test achieved 1.37 value, which is lower than that of the dynamometer test. In the future study the more precise research is needed to estimate the relation factor on vehicle test.

• Transactions of Materials Processing
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• v.10 no.4
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• pp.319-328
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• 2001

Quantitative evaluation of the tribological conditions at the tool-workpiece interface in metal forming is usually accomplished by the ring compression test. This paper describes an experimental investigation into friction factor under warm forming conditions according to the lubricants and the lubricating methods using the ring compression test. Four different lubricants, two water based graphite and two oil based graphite lubricants, and three different lubricating methods were applied in the experiments. Calibration curves with the friction shear factor were obtained using FEM analysis and verified by the experimental results. The influence of lubricant and lubricating methods on friction are discussed. In the ring compression test, the lower friction factor got to spray the oil based lubricant on die and billet in warm forging temperature.

• 한국데이터정보과학회:학술대회논문집
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• 2003.10a
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• pp.39-47
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• 2003

The Bayes factors with improper noninformative priors are defined only up to arbitrary constants. So, it is known that Bayes factors are not well defined due to this arbitrariness in Bayesian hypothesis testing and model selections. The intrinsic Bayes factor by Berger and Pericchi (1996) and the fractional Bayes factor by O'Hagan (1995) have been used to overcome this problems. This paper suggests intrinsic priors for testing the equality of two lognormal means, whose Bayes factors are asymptotically equivalent to the corresponding fractional Bayes factors. Using proposed intrinsic priors, we demonstrate our results with a simulated dataset.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.09a
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• pp.115-119
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• 2001

Contaminant retardation factor is derived from the colloidal and contaminant transport equations for a four-phase porous medium: an aqueous phase, two mobile colloidal phases, and a solid matrix. It is assumed that the contaminant sorption to solid matrix and colloidal particles and the colloidal deposition on solid matrix follow the linear isotherms. The behavior of the contaminant retardation factor in response to the change of model parameters is examined employing the experimental data of Magee et al. (1991) and Jenkins and Lion (1993). In the four-phase system, the contaminant retardation factor is determined by both the contaminant association with solid matrix and colloidal particles and the colloidal deposition on solid matrix. The contaminant mobility is enhanced when the affinity of contaminants to mobile colloids increases. In addition, as the affinity of colloids to solid matrix decreases, the contaminant mobility increases.