• Women's Health Nursing
• /
• v.26 no.4
• /
• pp.326-335
• /
• 2020

Purpose: This study was conducted to evaluate the construct validity, reliability, measurement invariance, and latent mean differences in the Breastfeeding Adaptation Scale-Short Form (BFAS-SF) for use with mothers at 2 weeks postpartum. Methods: This methodological study was designed to evaluate the validity, reliability, and measurement invariance of the BFAS-SF at 2 weeks postpartum, with data collected from 431 breastfeeding mothers. Confirmatory factor analysis and multi-group confirmatory factor analysis were conducted to assess the factor structure and the measurement invariance across employment status, delivery mode, parity, and previous breastfeeding experience, and the latent mean differences were then examined. Results: The goodness of fit of the six-factor model at 2 weeks postpartum was acceptable. Multi-group confirmatory factor analysis supported strict invariance of the BFAS-SF across employment status and delivery mode. Full configural invariance, full metric invariance, and partial scalar invariance across parity and full configural invariance and full metric invariance across previous breastfeeding experience were supported, respectively. The results for latent mean differences suggested that mothers who were employed showed significantly higher scores for breastfeeding confidence. Mothers who had a vaginal delivery showed significantly higher scores for sufficient breast milk and baby's feeding capability. Multiparous mothers showed significantly higher scores for baby's feeding capability and baby's satisfaction with breastfeeding. Conclusion: The validity and reliability of the BFAS-SF at 2 weeks postpartum are acceptable. It can be used to compare mean scores of breastfeeding adaptation according to employment status, delivery mode, and parity.

• Journal of Ocean Engineering and Technology
• /
• v.3 no.2
• /
• pp.587-587
• /
• 1989

• International Journal of Highway Engineering
• /
• v.14 no.6
• /
• pp.167-173
• /
• 2012

PURPOSES : This study is to develop speed correction factor for more realistic Level-of-Service(LOS) at multilane highway. METHODS : In this study, we compared speed difference the degree of speed reductions in actual multilane road conditions with speed reduction considering speed correction factor presented in highway capacity manual using statistical techniques. And also we presents new speed correction factor analyzing collected data at national highway No.1 (Goyang~Wolrung). RESULTS : The result of analyzing and comparing new suggested speed correction factor with speed correction factor in Korea Highway Capacity Manual (KHCM) shows RMSE (Root Mean Square Error) in new speed correction factor (RMSE 1.5) is much lower than existing speed correction factor (RMSE 13.4). New suggested speed correction can be used for analyzing Level-of-Service at multilane highway. And also we suggests improvements for analysis procedure in analyzing Level-of-Service at multilane highway CONCLUSIONS : As a result of comparing differences, we draw the causes that effect the differences in speed and suggest new speed correction factor that consider traffic volumes. It can be more rational because it uses speed correction factor which can consider more realistic traffic conditions, etc.

• Journal of KSNVE
• /
• v.8 no.4
• /
• pp.706-714
• /
• 1998

The purpose of this study is to analyse the main factors and attributes of psychological evaluation to noise. For this purpose, a psycho-acustic experiment was conducted by using the method of rating scale. 52 subjects were participated in the experiment, 20 stimuli were presented to subjects in random order with 23 adjectives. As a result of factor analysis, it was found that the primary factors for evaluating the quality of noise subjectively are four factors of unpleasantness, intensity, irregularity, and sharpness. And, as a result of MDPREF(multi-dimensional analysis of preference data), it was found that the noise sources including the factors of unpleasantness, intensity, and irregularity are related to the sounds of hammering in construction field, car horn, road traffic, idling of car, and printing by computer printer, and the factor of sharpness are the sounds of car siren, claps of thunder, car horn, and snowstorm etc.

• Journal of Korea Society of Industrial Information Systems
• /
• v.20 no.4
• /
• pp.75-87
• /
• 2015

A redundant structure typically consists of primary component and standby component taking over the function of the primary component when the primary component fails. In this research, we consider a redundant structure in which a standby component can take over the function of more than one primary component when primary components fail. And we assume that the system has multi-state according to the states of components while all components have two states. This system is called as the multi-state redundant system with a multi-functional standby component. This type of redundant structure is frequently adapted by the system such as an aircraft in which the weight is an important design factor. In this paper, we propose new reliability model for this multi-state redundant system with a multi-functional standby component in order for evaluating the reliability of the system. Under the assumption that all components have constant failure rate, we evaluate the reliability of the system by applying Markov analysis method. And we investigate the effect of the multi-functional standby component by comparing reliabilities of the parallel system with multi-functional standby component and a simple parallel system and a parallel system with redundant structure.

• KIEAE Journal
• /
• v.14 no.6
• /
• pp.93-97
• /
• 2014

Curtain wall system of office buildings has recently become very common in Korea. As the multi-layer curtain glazing is exposed to outdoor environment, it is very subjected to direct environmental impact. Consequently, breakage and cracks of glazing due to heat expansion is frequently observed. This study explores various causes and aspects for destruction of multi-layer glazing. A sensitivity analysis was performed on the basis that thermal changes causes damage to the multi-layer glazing. Air temperature in air cavity within the multi-layer glazing was examined to find its effect on multi-layer glazing breakage. Analysis showed high deflection to depth ratio of 1:1.8 and that higher the aspect ratio, smaller is the deflection. Allowable pressure showed that the weakest value is for aspect ratio of 1:2.9. Sensitivity analysis by the area of the glazing showed that as area of glazing becomes higher, allowable pressure and deflection-depth ratio becomes smaller. For allowable pressure and allowable deflection-depth within air cavity, the glazing breakage occurred at least $107^{\circ}C$. The results from glazing breakage by thermal factor shows that it is hard to break the glazing with only an increase in air cavity temperature in multi-layer glazing applied in buildings.

• Wind and Structures
• /
• v.36 no.1
• /
• pp.1-14
• /
• 2023

To evaluate the wind shielding effect of bridge towers with multiple limbs on high-speed trains, a wind tunnel test was conducted to investigate the aerodynamic characteristics of vehicles traversing multi-limb towers, which represented a combination of the steady aerodynamic coefficient of the vehicle-bridge system and wind environment around the tower. Subsequently, the analysis model of wind-vehicle-bridge (WVB) system considering the additional moments caused by lift and drag forces under nonuniform wind was proposed, and the reliability and accuracy of the proposed model of WVB system were verified using another model. Finally, the factors influencing the wind shielding effect of multi-limb towers were analyzed. The results indicate that the wind speed distributions along the span exhibit two sudden changes, and the wind speed generally decreases with increasing wind direction angle. The pitching and yawing accelerations of vehicles under nonuniform wind loads significantly increase due to the additional pitching and yawing moments. The sudden change values of the lateral and yawing accelerations caused by the wind shielding effect of multi-limb tower are 0.43 m/s² and 0.11 rad/s² within 0.4 s, respectively. The results indicate that the wind shielding effect of a multi-limb tower is the controlling factor in WVB systems.

• Journal of the Korean Society of Costume
• /
• v.61 no.10
• /
• pp.119-134
• /
• 2011

The present study proposes and tests an integrative model for global consumers to examine the relation among fashion marketing mix, brand attitude, brand loyalty, and purchase intention in the jeans market. The questionnaire surveys 692 consumers in the United States, China, and France. The statistical analysis methods that are used are as follows: frequency analysis, factor analysis, SEM analysis, and multi-group analysis. The results show that fashionability, perceived quality, and advertising have a direct and also a positive effect on brand attitude; however, advertising didn't have a direct effect on purchase intention. In addition, the results of the SEM analysis show that brand attitude leads to brand loyalty, while also showing a direct and indirect positive effect on purchase intention. Furthermore, the multi-group analysis reveals significant differences in SEM among countries such as the United States, China, and France.

• Earthquakes and Structures
• /
• v.20 no.4
• /
• pp.389-403
• /
• 2021

Skewed bridges, being irregular structures with complicated dynamic behavior, are more susceptible to earthquake damage. Reliable seismic-resistant design of skewed bridges can be achieved by accurate determination of nonlinear seismic demands. However, the effect of geometric characteristics on the response modification factor (R-factor) is not accounted for in bridge design practices. This study attempts to investigate the effects of changes in the number of spans, skew angle and bearing stiffness on R-factor values and to assess the seismic fragility of skewed bridges. Results indicated that changes in the skew angle had no significant effect on R-factor values which were in consonance with code-prescribed R values. Also, unlike the increase in the number of spans that resulted in a decrease in the R-factor, the increase in bearing stiffness led to higher R-factor values. Findings of the fragility analysis implied that although the increase in the number of spans, as well as the increase in the skew angle, led to a higher failure probability, greater values of bearing stiffness reduced the collapse probability. For practicing design engineers, it is recommended that maximum demands on substructure elements to be calculated when the excitation angle is applied along the principal axes of skewed bridges.

• Korean Journal of Child Studies
• /
• v.29 no.4
• /
• pp.249-268
• /
• 2008

The Korean version of the Multidimensional Students' Life Satisfaction Scale for children(K-MSLSS) assesses children's subjective perceptions of Life Satisfaction(LS) in five conceptually relevant domains : Friends, School, Family, Living Environment, and Self. The purpose of the present study was to validate the five-factor structure of the K-MSLSS using Confirmatory Factor Analysis(CFA) procedures by means of the AMOS 7.0 statistical program. Of the 681 children(10.5 years, SD=1.1) recruited from three public elementary schools in Seoul 431 children were the calibration sample and 430 children were the validation sample. Results of the analyses found that the five-factor structure of K-MSLSS is applicable for use with Korean children from 9-12 years of age regardless of gender.