• Journal of Applied Reliability
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• v.10 no.4
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• pp.251-263
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• 2010

Modelling for failures is important for reliability analysis since failures of products such as automobiles occur as both time and usage progress and the results from the proper analysis of the two-dimensional data can be used for establishing warranty assurance policy. Hence, in this paper general issues which concern modelling failures are discussed, and both one-dimensional approaches and two-dimensional approaches to two-dimensional data are investigated. Finally non-parametric approaches to two-dimensional data are presented as a means of exploratory data analyses.

• Informatization Policy
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• v.18 no.1
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• pp.45-54
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• 2011

The purpose of this study is to analyze the selection behavior decision model of telecommunications service under the telecommunication environments with joining the WiBro and 3GPP LTE-Advanced service at the sam time. The research results are as follows. First, mobile telecommunication service selection behavior is correlated with each other between WiBro and 3GPP LTE-Advanced service. Second, in the bivariate probit model estimates such as age, income, expenditure and income variable are important decision variables of WiBro and 3GPP LTE-Advanced service selection behavior. Gender and service using years, however, are not an important variables. The single and bivariate probit estimate results show the same estimation results. Finally, the two service selecting predictions by using the bivariate probit estimated results, 28.6% of WiBro and 25.3% of 3GPP LTE-Advanced were expected. Also, chance to join the two telecommunications services simultaneously is 19.3%. Therefore, WiBro selection probability is a little higher than 3GPP LTE-Advanced. The implications of these results, the future telecommunications service selection will be determined by economic factors such as income and expenditure. Thus, to enable the WiBro, policy means for reducing the excessive telecommunications expenditure are needed in the future.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.8
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• pp.1085-1090
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• 2002

Genetic parameters for birth weights (BWT), calving ease scores observed from calves born by heifers (CEH), and calving ease scores observed from calves born by cows (CEC) were estimated using Bayesian methodology with Gibbs sampling in different threshold animal models. Data consisted of 77,458 records for calving ease scores and birth weights in Gelbvieh cattle. Gibbs samplers were used to obtain the parameters of interest for the categorical traits in two univariate threshold animal models, a bivariate threshold animal model, and a three-trait linear-threshold animal model. Samples of heritabilities and genetic correlations were calculated from the posterior means of dispersion parameters. In a univariate threshold animal model with CEH (model 1), the posterior means of heritabilities for calving ease was 0.35 for direct genetic effects and 0.18 for maternal genetic effects. In the other univariate threshold model with CEC (model 2), the posterior means of heritabilities of CEC was 0.28 for direct genetic effects and 0.18 for maternal genetic effects. In a bivariate threshold model with CEH and CEC (model 3), heritability estimates were similar to those in unvariate threshold models. In this model, genetic correlation between heifer calving ease and cow calving ease was 0.89 and 0.87 for direct genetic effect and maternal genetic effects, respectively. In a three-trait animal model, which contained two categorical traits (CEH and CEC) and one continuous trait (BWT) (model 4), heritability estimates of CEH and CEC for direct (maternal) genetic effects were 0.40 (0.23) and 0.23 (0.13), respectively. In this model, genetic correlation estimates between CEH and CEC were 0.89 and 0.66 for direct genetic effects and maternal effects, respectively. These estimates were greater than estimates between BWT and CEH (0.82 and 0.34) or BWT and CEC (0.85 and 0.26). This result indicates that CEH and CEC should be high correlated rather than estimates between calving ease and birth weight. Genetic correlation estimates between direct genetic effects and maternal effects were -0.29, -0.31 and 0.15 for BWT, CEH and CEC, respectively. Correlation for permanent environmental effects between BWT and CEC was -0.83 in model 4. This study can provide genetic evaluation for calving ease with other continuous traits jointly with assuming that calving ease from first calving was a same trait to calving ease from later parities calving. Further researches for reliability of dispersion parameters would be needed even if the more correlated traits would be concerned in the model, the higher reliability could be obtained, especially on threshold model with property that categorical traits have little information.

• The Korean Journal of Applied Statistics
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• v.22 no.4
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• pp.687-695
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• 2009

The Bayesian multiple change-point estimation has been applied to the daily means of ozone and PM10 data in Seoul for the period 1999. We focus on the detection of multiple change-points in the ozone and PM10 bivariate vectors by evaluating the posterior probabilities and Bayesian information criterion(BIC) using the stochastic approximation Monte Carlo(SAMC) algorithm. The result gives 5 change-points of mean vectors of ozone and PM10, which are related with the seasonal characteristics.

• Korean Journal of Child Studies
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• v.34 no.2
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• pp.27-42
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• 2013

The purpose of this study was to examine: (1) the relationships among internalization of sociocultural attitudes toward appearance, body comparison, and body dissatisfaction in adolescent girls; and (2) whether or not body comparison mediates the relationship between internalization of sociocultural attitudes toward appearance and body dissatisfaction. The participants consisted of 291 girls from fifth through ninth grades. The data were collected by means of questionnaires given in classroom settings. The findings are as follows: there are significant bivariate correlations among internalization of sociocultural attitudes toward appearance, body comparison, and body dissatisfaction. Furthermore, body comparison partially mediates the relationship between internalization of sociocultural attitude towards appearance and body dissatisfaction. These results seem to indicate that the idea that there are multiple standards of beauty and individuality for every person should be promoted, and this in turn could lower the risk of body dissatisfaction among adolescent girls.

• Journal of Communications and Networks
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• v.9 no.1
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• pp.67-74
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• 2007

The performance of dual diversity receivers operating over correlated Ricean fading channels is analyzed. Using a previously derived rapidly converging infinite series representation for the bivariate Ricean probability density function, analytical expressions for the statistics of dual-branch selection combining, maximal-ratio combining, and equal-gain combining output signal-to-noise ratio (SNR) are derived. These expressions are employed to obtain novel analytical formulae for the average output SNR, amount of fading, average bit error probability, and outage probability. The proposed mathematical analysis is used to study various novel performance evaluation results with parameters of interest the fading severity, average input SNRs, and the correlation coefficient. The series convergence rate is also examined verifying the fast convergence of the analytical expressions. The accuracy of most of the theoretical performance evaluation results are validated by means of computer simulations.

• Journal of Korean Institute of Industrial Engineers
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• v.31 no.2
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• pp.99-105
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• 2005

A quality inspection procedure interchangeably using the performance and surrogate variables is proposed. At the start of the inspection, the continuous performance variable is measured for all items. As soon as iconsecutive items are found to be conforming, the continuous surrogate variable is measured instead of the performance variable. If an item is rejected, the inspection based on the performance variable is resumed. It is assumed that the performance variable and the surrogate variable are jointly normally distributed with known means and standard deviations. The average outgoing quality (AOQ) expression is derived, and the methods of finding the inspection procedure with a specified average outgoing quality limit (AOQL) are presented.

• The Korean Journal of Applied Statistics
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• v.25 no.6
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• pp.999-1008
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• 2012

A Bayesian multiple change-point model for small data is proposed for multivariate means and is an extension of the univariate case of Cheon and Yu (2012). The proposed model requires data from a multivariate noncentral $t$-distribution and conjugate priors for the distributional parameters. We apply the Metropolis-Hastings-within-Gibbs Sampling algorithm to the proposed model to detecte multiple change-points. The performance of our proposed algorithm has been investigated on simulated and real dataset, Hanwoo fat content bivariate data.

• Journal of Distribution Science
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• v.17 no.10
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• pp.27-39
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• 2019

Purpose - This study explores the relationships between e-Marketing and perceived service quality with brand trust and loyalty towards the brand of mobile telephone operators in Kosovo. Research design, data, and methodology - The conceptual model of four constructs was developed, while each construct consisted of the set of variables measured by using five-point Likert scale. The primary data was collected via an online survey through SurveyMonkey, distributed via Facebook and email. The collected data were cleaned, validated and tested for its consistency through Cronbach's Alpha; ensured that five assumptions of multiple linear regression are met. To assess the relationships between outcome variable and dependent variables of the model, performed the bivariate correlation, simple, multiple linear and hierarchical regression. Results - Perceived service quality has a positive significant effect on brand trust and loyalty. e-Marketing presents moderating direct effect on brand loyalty, and slightly higher effect through brand trust of the mobile telephone operators in Kosovo. Conclusions - The perceived service quality and brand trust are key determinants in achieving brand loyalty in telecommunication industry, followed by e-Marketing as means to creating expectations, delivering on promise to meet customers' perceptions for service quality with a purpose of building trust, that leads to loyalty towards the brands of mobile operators in Kosovo.

• Women's Health Nursing
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• v.17 no.2
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• pp.126-136
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• 2011

Purpose: The increase of cosmetic surgery procedures is partly motivated by more positive attitude toward cosmetic surgery as a means of improving physical appearance. In this study factors expected to predict need for cosmetic surgery were examined. Methods: A descriptive design was used with 321 high school girls who completed a questionnaire about sociocultural attitudes toward appearance, body image, self-esteem, and need for cosmetic surgery. Stepwise multiple regression analysis was performed to examine factors affecting need for cosmetic surgery. Results: Bivariate correlations showed that need for cosmetic surgery was positively correlated with internalization and awareness of sociocultural attitudes toward appearance, and appearance orientation in body image and negatively correlated with self-esteem and ideal body mass index (BMI). Multiple regression showed that the predictive variables explained 22.1% in need for cosmetic surgery. The significant factors influencing need for cosmetic surgery were greater internalization and awareness of sociocultural attitudes toward appearance, better appearance evaluation and higher appearance orientation in body image, lower self-esteem, and lower ideal BMI. Conclusion: Overall, results of this research suggest that prevention of media influence and body image disturbances, and promotion of self-esteem are very important to young women.