• Journal of Korean Society for Quality Management
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• v.15 no.1
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• pp.20-32
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• 1987

Estimation for the parameters of a bivariate exponential (BVE) model of Marshall and Olkin (1967) is investigated for the cases of complete sampling and time-truncated parallel sampling. Maximum likelihood estimators, method of moment estimators and Bayes estimators for the parameters of a BVE model are obtained and compared with each other. A Monte Cario simulation study for a moderate sized samples indicates that the Bayes estimators of parameters perform better than their maximum likelihood and method of moment estimators.

• Communications for Statistical Applications and Methods
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• v.10 no.1
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• pp.203-210
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• 2003

In a standard Metropolis-type Monte Carlo simulation, the proposal distribution cannot be easily adapted to "local dynamics" of the target distribution. To overcome some of these difficulties, Duane et al. (1987) introduced the method of hybrid Monte Carlo(HMC) which combines the basic idea of molecular dynamics and the Metropolis acceptance-rejection rule to produce Monte Carlo samples from a given target distribution. In this paper, using the HMC within Gibbs sampler, an asymptotical estimate of the smoothing mean and a general solution to state space modeling in Bayesian framework is obtaineds obtained.

• Journal of the Korean Home Economics Association
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• v.37 no.6
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• pp.77-96
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• 1999

The purpose of this study was to examine the effect of family-of-origin, personal and spousal characteristics, mediated by communication and problem-solving behavior, on marital quality and stability. On the basis of previous literature, the theoretical model was specified, estimated, and evaluated for adequacy of statistical fit for samples of 214 married women. Although the initial model was not supported by data, the revised model fitted the data adequately. Results of structural equation modeling indicated family-of-origin and communication behavior directly affected marital quality. However, the personal and spousal characteristics were linked with marital quality and stability only if they were mediated by communication and problemsolving behavior. Communication behavior was strongly related to marital quality and stability both directly and indirectly through problem-solving behavior. The model also showed marital quality can be an antecedent variable for marital stability. The findings of results is to generate more broad-minded thinking about how communication behavior, marital quality, and marital stability are interrelated.

• Korean Medical Education Review
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• v.16 no.2
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• pp.57-66
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• 2014

Burnout research has mostly been performed in human service fields. However, it has recently been expanded to cover diverse settings and even non-occupational samples, such as students. In this study, we defined the construct of academic burnout, which is the burnout experienced by students. Next, we described the concept of academic burnout by introducing measurements for assessing academic burnout. On the basis of the demand-control model (DCM) and effort-reward imbalance model (ERIM), which are the most predominant theoretical burnout models, we described the causal factors and the pathway to experiencing academic burnout symptoms. The ERIM was a more influential model than the DCM when explaining the academic burnout of Korean students. Based on the results of previous longitudinal studies on academic burnout, we recognized emotional exhaustion and academic inefficacy as the initial symptoms of academic burnout. Finally, we discussed the prevention and intervention programs with specific components that should be included in those programs.

• Asian Journal of Atmospheric Environment
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• v.5 no.1
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• pp.1-7
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• 2011

This study assesses the dispersion and emission rates of odor form industrial area source. CALPUFF and AERMOD Gaussian models were used for predicting downwind odor concentration and calculating odor emission rates. The studied region was Seobu industrial complex in Korea. Odor samples were collected five days over a year period in 2006. In-site meteorological data (wind direction and wind speed) were used to predict concentration. The BOOT statistical examination software was used to analyze the data. Comparison between the predicted and field sampled downwind concentration using BOOT analysis indicates that the CALPUFF model prediction is a little better than AERMOD prediction for average downwind odor concentrations. Predicted concentrations of AERMOD model have a little larger scatter than that of CALPUFF model. The results also show odor emission rates of Seobu industrial complex area were an order of 10 smaller than that of beef cattle feed lots.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.29 no.1
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• pp.143-150
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• 2006

Box-Cox model and T-factor method have been widely used to measure economic depreciations for industrial property. The Box-Cox model which combines economic efficiency with depreciation pattern is here extended to the reliability function. To do so a Rayleigh distribution which has been used to estimate the reliability of current assets was chosen as an efficiency curve of marginal productivity. Such an approach provides the possibility to classify the efficiency curves into four categories. It is also possible to analyze the types of depreciation curves. Therefore, the power family of a non-linear Box-Cox model could be set at certain constant values, then the model can be transformed into a linear model to estimate the economic depreciation rates by utilizing the reliability function. Estimating the resultant linear regression equation requires minimal number of observations, while at the same time facilitating the test of hypothesis on depreciation rates.

• International Commerce and Information Review
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• v.8 no.1
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• pp.33-50
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• 2006

This research develops, and empirically test a model for explaining/predicting the Determinants and Satisfaction of Portal Cite in Internet Initiation Page. Also this paper describes a theoretical model for investigating the service quality satisfaction in the Internet Initiation Page. This research is the first to empirical test the causal relationships in determinants of Portal Cite. The model of the satisfaction for Portal Cite are tested here using data from 224 samples. Based on the research model, a comprehensive set of hypotheses is formulated and a methodology for testing them is outlined. some of the hypotheses are tested empirically to demonstrate the applicability of the theoretical model. In examining the relationships of the determinants factors, satisfaction show in significantly by Convenience, Information Provided, Entertainments, Interaction but that show in not significantly by the Trustworthiness, In addition, Portal Cite in Internet Initiation Page shows indirect effect between customer satisfaction and referral.

• The Journal of Information Systems
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• v.16 no.3
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• pp.133-159
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• 2007

The primary purpose of this study is to examine the effects of perceived characteristics on user satisfaction and continuous usage intention in personal communities. We developed a research model based on the literature reviews of personal communities, TAM, perceived risks, and satisfaction. The research model includes perceived playfulness, perceived ease of use, perceived usefulness, and perceived risk as perceived characteristics in personal communities. For validation of this theoretical model, we survey the users of 'Mini-hompy', one of the most popular personal communities in Korea. The research model was empirically verified by structural equation model analysis with data collected from 407 samples. Analysis of the results indicates that perceived ease of use is positively related perceived playfulness and perceived usefulness. Perceived playfulness, perceived ease of use, and perceived risks are significantly related to satisfaction. User's satisfaction has positive relationship with continuous usage intention in personal communities.

• Journal of Ocean Engineering and Technology
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• v.26 no.2
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• pp.39-47
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• 2012

The objective of this study was to develop a strength prediction model using a polynomial regression analysis based on the experimental results obtained from ninety samples. As the results of a correlation analysis between various mixing factors and unconfined compressive strength using SPSS (statistical package for the social sciences), the governing factors in the strength of lightweight soil were found to be the crumb rubber content, bottom ash content,and water-cement ratio. After selecting the governing factors affecting the strength through the correlation analysis, a strength prediction model, which consisted of the selected governing factors, was developed using the polynomial regression analysis. The strengths calculated from the proposed model were similar to those resulting from laboratory tests (R2=87.5%). Therefore, the proposed model can be used to predict the strength of lightweight mixtures with various mixing ratios without time-consuming experimental tests.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.11a
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• pp.437-442
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• 2000

An alternative inverse feedback structure for adaptive active control of periodic noise is introduced for systems with nonminimum phase cancellation path. To obtain the inverse model of the nonminimum phase cancellation path, the cancellation path model can be factorized into a minimum phase term and a maximum phase term. The maximum phase term containing unstable zeros makes the inverse model unstable. To avoid the instability, we alter the inverse model of the maximum phase system into an anti-causal FIR one. An LMS predictor estimates the future samples of the noise, which are necessary for causality of both anti-causal FIR approximation for the stable inverse of the maximum phase system and time-delay existing in the cancellation path. The proposed method has a faster convergence behavior and a better transient response than the conventional FX-LMS algorithms with the same internal model control structure since a filtered reference signal is not required. We compare the proposed methods with the conventional methods through simulation studies.