• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2000.11a
• /
• pp.862-865
• /
• 2000

The object of this paper is to evaluate the surface roughness using the experimental equation of surface roughness, which is developed in turning by an orthogonal array method. $L_9{3^4}$ orthogonal array method, one of fractional factorial design has been used to study effects of main cutting parameters such as cutting speed, feed rate and depth of cut, on the surface roughness. And the analysis of variance (ANOVA)-test has been used to check the significance of cutting parameters. Using the result of ANOVA-test, the experimental equation of surface roughness, which consists of only significant cutting parameter - feed rate, has been developed. The coefficient of determination of this equation is 0.962.

• Korean Journal of Human Ecology
• /
• v.18 no.2
• /
• pp.381-395
• /
• 2009

This study was conducted to investigate effects of self concept of children consumers on consumption propensity of online items according to gender by considering that self, which means a thought on ownself, is expressed as online items in cyber space. Totally, 760 copies of the questionnaire were distributed and 716 ones were finally used as data for analysis in this study. The data were analyzed by using SPSS 14.0 and factorial analysis, Cronbach' ${\alpha}$, t-test, cross tabulation analysis and multiple regression were conducted. The results of this study could be summarized as follows. First, the factorial analysis performed to examine types of self concept found four factorial structures - justness, social, academic and family self. In addition, the factorial analysis done to determine compositional factors of irrational consumption propensity of children consumers showed three factorial structures - impulse buying, conspicuous consumption and imitative consumption. When the effects of personal variables, item-transaction variables and self concept on irrational consumption propensity of children consumers were investigated according to gender, significant factors affecting consumption propensity of both of the males and females were a monthly pocket money, time using the Internet and major transaction items. In addition, parents' permission for purchasing items, justness self and family self were found to be variables affecting consumption propensity in the male children. On the contrary, self concept of female children did not affect irrational consumption propensity.

• The Korean Journal of Pain
• /
• v.34 no.4
• /
• pp.501-508
• /
• 2021

Background: Yellow flags are psychosocial factors shown to be indicative of long-term chronicity and disability. The purpose of the study was to evaluate the psychometric properties of the Turkish Yellow Flag Questionnaire (YFQ) in patients with chronic musculoskeletal pain (CMP). Methods: The cross-cultural adaptation was conducted with translation and back-translation of the original version. Reliability (internal consistency and test-retest) was examined for 231 patients with CMP. Construct validity was assessed by correlating the YFQ with the Hospital Anxiety and Depression Scale (HADS), Orebro Musculoskeletal Pain Questionnaire (OMPQ), and Tampa Kinesiophobia Scale (TKS). Factorial validity was examined with both exploratory and confirmatory factorial analysis. Results: The YFQ showed excellent test/retest reliability with an Intraclass correlation coefficient of 0.82. The internal consistency was moderate (Cronbach's alpha of 0.797). As a result of the exploratory factor analysis, there were 7 domains compatible with the original version. As a result of confirmatory factor analysis, the seven-factor structure of YFQ was confirmed. There was a statistically significant correlation between YFQ-total score and OMPQ (r = 0.57, P < 0.001), HADS-anxiety (r = 0.32, P < 0.001), HADS-depression (r = 0.44, P < 0.001), and TKS (r = 0.37, P < 0.001). Conclusions: This study's results provide considerable evidence that the Turkish version of the YFQ has appropriate psychometric properties, including test-retest reliability, internal consistency, construct validity and factorial validity. It can be used for evaluating psychosocial impact in patients with CMP.

• The Korean Journal of Applied Statistics
• /
• v.8 no.2
• /
• pp.87-97
• /
• 1995

When there is no main effcts or only one main effect in a $2 \times 2$ factorial design, Type I error rates and power for the rank transformed F test (FR test) for interaction are nearly equal to those of the classical F test. However the power of FR test is quite superior under the exponential distribution rather than the of FR test is quite superior under the exponential distribution rather than the normal distribution. Meanwhile when both main effects are in the model, Type I error rates of FR test, compared with those of F test, decrease as the effect size increases and are dependent on the fashion in which main effects are constructed. In addition, the power of FR test increases as the effect size and the sample size increase and is highly dependent on the manner in which main effects are constructed and the type of population distribution.

• Computers and Concrete
• /
• v.12 no.5
• /
• pp.651-668
• /
• 2013

Concrete structures need repairing due to various reasons such as deteriorative effects, overloading, poor quality of workmanship and design failures. Cement based repair mortars are the most widely used solutions for concrete repair applications. Various factors may affect the bond strength between concrete substrate and repair mortars. In this paper, the effects of polymer additives, strength of the concrete substrate, surface roughness, surface wetness and aging on the bond between concrete substrate and repair mortar has been investigated. Full factorial experimental design is employed to investigate the main and interaction effects of these factors on the bond strength. Analysis of variance (ANOVA) under design of experiments (DOE) in Minitab 14 Statistical Software is used for the analysis. Results showed that the interaction bond strength is higher when the application surface is wet and strength of the concrete substrate is comparatively high. According to the results obtained from the analysis, the most effective repair mortar additive in terms of bonding efficiency was styrene butadiene rubber (SBR) within the investigated polymers and test conditions. This bonding ability improvement can be attributed to the self-flowing ability, high flexural strength and comparatively low air content of SBR modified repair mortars. On the other hand, styrene acrylate rubber (SAR) modified mortars was found incompatible with the concrete substrate.

• International Journal of Computer Science & Network Security
• /
• v.21 no.12
• /
• pp.157-164
• /
• 2021

The aim of this study is to provide empirical evaluation of the accuracy of data-model fit using growing levels of invariance models. Overall model accuracy of factor solutions was evaluated by the examination of the order for testing three levels of measurement invariance (MIV) starting with configural invariance (model 0). Model testing was evaluated by the Chi-square difference test (∆𝛘²) between two groups, and root mean square error of approximation (RMSEA), comparative fit index (CFI), and Tucker-Lewis index (TLI) were used to evaluate the all-model fits. Factorial invariance result revealed that stability of the models was varying over increasing levels of measurement as a function of variable-to-factor ratio (VTF), subject-to-variable ratio (STV), and their interactions. There were invariant factor loadings and invariant intercepts among the groups indicating that measurement invariance was achieved. For VTF ratio (3:1, 6:1, and 9:1), the models started to show accuracy over levels of measurement when STV ratio was 6:1. Yet, the frequency of stability models over 1000 replications increased (from 69% to 89%) as STV ratio increased. The models showed more accuracy at or above 39:1 STV.

• Communications for Statistical Applications and Methods
• /
• v.3 no.3
• /
• pp.283-290
• /
• 1996

The simulation study shows that the rank transform test has relatively superior power advantages over the parametric analysis of variance test in many cases for a $2^3$ factorial design, particularly with heavy-tailed distributions of the error terms. However the rank transform test should be cautiously used when all main effects and interactions related to a testing effect are possibly present at the same time.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2012.05a
• /
• pp.1087-1088
• /
• 2012

• Proceedings of the Korea Contents Association Conference
• /
• 2005.11a
• /
• pp.247-253
• /
• 2005

In this paper, I was undertaken to identify factorial structure of physical fitness components for male high school Taekwondo players. In order to accomplish this purpose, the selected 8 physical fitness test were conducted to 50 male high school Taekwondo players. For the concretely, this study was conducted to physical fitness battery was grip strength, vertical jump, standing trunk flexion, sit-ups, closed eyes foot balance, 10m shuttle run, 50m run, and 1600m run. Factor analysis was applied for analyzing factorial structure of each physical fitness components.

• Journal of the Korean Statistical Society
• /
• v.25 no.3
• /
• pp.419-432
• /
• 1996

When interactions are not present in a three-way layout, the lim-iting null distribution of the F statistic for testing main effects when applied to the rank-score transformed data is the same as the limiting null distribution of the usual F statistic when applied to the normal data. The simulation results exhibit that the rank transform test is robust with respect to significance level and powerful for testing main effects in a three-way factorial experiment.