• Journal of the Korea Society for Simulation
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• v.20 no.2
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• pp.1-10
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• 2011

In queueing network analysis, arrival processes are usually modeled as renewal processes by matching mean and variance. The renewal approximation simplifies the analysis and provides reasonably good estimate for the performance measures of the queueing systems under moderate conditions. However, high variability in arrival process or in service process requires more sophisticated approximation procedures for the variability parameter of departure/arrival processes. In this paper, we propose an heuristic approach to refine Whitt's variability function with the k-interval squared coefficient of variation also known as the index of dispersion for intervals(IDI). Regression analysis is used to establish an empirical relationships between the IDI of arrival process and the IDI of departure process of a queueing system.

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

• Human Ecology Research
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• v.54 no.5
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• pp.529-539
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• 2016

This study confirmed shopping behavior of Korean young overseas tourists and its effect on travel evaluation. I first identified core factors of travel activity preference, travel shopping propensity, and shopping products. The effect of shopping product satisfaction on tour satisfaction and post-tour intention was then investigated. Based on travel activities, tourists were grouped, and their characteristics were compared. An online survey method was performed to obtain data of 20's-30's Korean unmarried people, while factor analysis, regression analysis, chi-square test, analysis of variance (ANOVA), and cluster analysis were applied to analyze data. The results were as follows. First, six travel activities (city life, art/shopping, cultural experience, entertainment, field experience, and friendship), three shopping propensity (novelty/uniqueness, utility, and prestige), and four product groups (fashion goods, household goods, crafts, and foods) were found by factor analyses. Second, travel activity tended to influence shopping propensity, which then influenced shopping products preference. All factors of travel activity seemed to affect the three travel shopping propensities. Third, shopping satisfaction was shown to affect tour satisfaction, and posttour behavior. Finally, four tourist groups (active, social, pleasure, and passive) differed in terms of preferred tour activities, shopping propensity, and tour behavior. Active tourists rated the highest scores and passive ones rated the lowest for most evaluations.

• Korean Parent-Child Health Journal
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• v.4 no.2
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• pp.32-42
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• 2002

This study was conducted to test the reliability and validity of "What my baby is like(WBL)" that was developed by Pridham et al. for measuring infant temperament. 37 subjects were participated four times-1, 3, 6, and 12months, and 146 cases were analyzed. The construct validity for the scale was tested by factor analysis with four factor loading solution based on the previous study. One item was excluded because total-item correlation was too low, so that the number of total items were eighteen. The analysis yielded four well defined factors: amenability and persistence, activity, reactivity, and adaptability. These four factors explained 57.62% of the variance in the infant temperament. The criterion related Validity was confirmed by the relationship between the infant temperament and HOME, and between the infant temperament maternal confidence in childrearing. The reliability of the scale was determined with Cronbach's alpha coefficient and Guttman split-half coefficient. Cronbach's alpha was .86, for 18 items, and Guttman split-half cofficient was .81. In subscale analysis, Cronbach's alpha was .56~.84. In conclusion, WBL showed a high degree of validity and reliability, suitable in Korean infants for measuring temperament. In the further study, it would be necessary to refine the concept of temperament and to analyze the correlation between WBL and other temperament inventory.

• The Research Journal of the Costume Culture
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• v.29 no.6
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• pp.865-880
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• 2021

The purpose of this study was to examine job competencies for sales training program development to maximize profits in fashion retailing. An empirical online survey was conducted from September to December 2019, and data was collected from 200 salespeople and store managers working in fashion stores. Results were analyzed using frequency analysis, factor analysis, variance analysis, and regression analysis with SPSS 25.0. The major findings of this study were as follows. First, the most important job competencies identified by fashion store managers were: sales sense know-how, customer service skills, and sales person's fashion style sense, product knowledge, fashion marketing and customer management. The job competency factors for sales training programs included empathy with the customer, product knowledge, communications and networking, basic job requirement, and sales skills. These five factors positively influenced the employment intentions and expectations of work performance of graduates. These factors also had a positive influence on the need of sales training program and intention to participate in retraining. Store managers in fashion retail thought the most appropriate period for on-the-job training was either 2-4 days or more than 1 week. The results of this study can be used as a base to develop training programs for job efficiency for salespeople in fashion retailing.

• Journal of Korean Public Health Nursing
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• v.36 no.1
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• pp.107-123
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• 2022

Purpose: This study was done to develop and test a scale to measure the homeboundness for low-income aged who live in the community. Methods: This was nursing methodology research. Homeboundness Scale development process was composed of construct identification based on concept analysis using the Hybrid model, 35 initial items. This number was reduced to 31 items through face validity tests by 7 experts. The preliminary Homeboundness Scale for low-income aged was administered to 240 aged who registered and received visiting health care service in the community health center located in S city. Data were analyzed using item analysis, factor analysis, Pearson correlation coefficients, and Cronbach's alpha. Results: Twenty-two items were selected for the final scale. Three factors evolved from the factor analysis, which explained 66.0% of the total variance. The internal consistency, Cronbach's alpha, was .945 and reliability of the subscales ranged from .890 to .934. Conclusion: Homeboundness Scale demonstrated acceptable validity and reliability. It can be used to assess the Homeboundness of the low-income aged in practice and research.

• Journal of Korea Water Resources Association
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• v.37 no.12
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• pp.993-1007
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• 2004

There are many different techniques for the estimation of the Hurst exponent. However, the techniques can produce different characteristics for the persistence of a time series each other. This study uses several techniques such as adjusted range, resealed range(RR) analysis, modified restated range(MRR) analysis, 1/f power spectral density analysis, Maximum Likelihood Estimation(MLE), detrended fluctuations analysis(DFA), and aggregated variance time(AVT)method for the Hurst exponent estimation. The generated time series from chaos and stochastic systems are analyzed for the comparative study of the techniques. Then this study discusses the advantages and disadvantages of the techniques and also the limitations of them.

• Journal of Biosystems Engineering
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• v.29 no.3
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• pp.261-266
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• 2004

This study was Performed to classify the acoustic emission(AE) signal due to surface cracking and moisture movement in the flat-sawn boards of oak(Quercus Variablilis) during drying using the principal component analysis(PCA) and artificial neural network(ANN). To reduce the multicollinearity among AE parameters such as peak amplitude, ring-down count event duration, ring-down count divided by event duration, energy, rise time, and peak amplitude divided by rise time and to extract the significant AE parameters, correlation analysis was performed. Over 96 of the variance of AE parameters could be accounted for by the first and second principal components. An ANN analysis was successfully used to classify the Af signals into two patterns. The ANN classifier based on PCA appeared to be a promising tool to classify the AE signals from wood drying.

• Asia Marketing Journal
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• v.17 no.1
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• pp.1-26
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• 2015

In the 21^st century, green consumer behavior, playing one of the core roles of sustainability, is still an important issue to green-related stakeholders. Because one of the major objectives of green-consumer research is an improvement of behaviors aligned with greening, this paper revisited socio-demographic variables and shed light on segmenting and profiling green consumers based on their connectedness between socio-demographic variables and green behaviors. Using correlations, factor analysis, analysis of variance, k-means cluster analysis and χ²-tests, this paper shows that socio-demographic variables differentially impact green-consumer behaviors. In order to profile green consumers, this paper additionally attempts to segment green-consumer groups. The results also coincide with former findings that socio-demographic variables relate significantly with segmented green-consumer group behaviors. General findings are summarized as: 1) older people used green practices more strongly than younger people, 2) females demonstrated better energy-saving and recycling practices compared to males, 3) marital status also significantly influenced green-related behaviors, 4) subjective social class had a significant influence on green-related behaviors, 5) education level and income, however, weakly influenced or showed no impact on green-related behaviors, and 6) a green consumer was classified as an 'active green consumer,' 'utilitarian green consumer,' or 'inactivated green consumer.' The utilitarian green consumer group distinctively behaved more strongly in energy-saving and recycling practices compared to the inactivated green consumer group, whereas active green consumers behaved more strongly on the whole, when compared to those in the inactivated green consumer group.

• Journal of Korea Society of Digital Industry and Information Management
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• v.14 no.1
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• pp.87-101
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• 2018

The purpose of this study is to develop the measuring instruments for evaluation criteria for Malcolm Baldrige National Quality Award(MBNQA), suitable for ICT Industries, and to analyze the cause-effect relationship between those criteria through aforementioned instruments. MBNQA is formed with seven categories: Leadership, Strategic planning, Focus on patients, other customers and markets, Measurement, analysis and knowledge management, Human resource focus, Process management and Results. As excluding the Human Resource Focus category, this study empirically examined the cause-effect relationship among six categories. In order to empirically examine the research model, this study calculated Cronbach's alpha and reliability index, thus examined the reliability and executed Exploratory Factor Analysis. Furthermore, Average Variance Extracted(AVE) is used to verify the discriminant validity. Lastly, the hypothesis testing was made complete through significance test on the paths between variables. The result of this study shows that both leadership and social responsibility have direct cause-effect relationship with Measurement, analysis and knowledge management, Human resource focus, Process management and also that this relationship has direct impact on Human resource focus, Measurement, analysis and knowledge management as well, consequently exerting influence on the result through Process management, Finance and Market data.