• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.04a
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• pp.85-86
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• 2022

Traditionally, the facility inspection was visually conducted by the managers, and consequently the result can be subjective because of different perspective and experience of them. To solve this problem, the studies on this topic has tried to integrate the UAS. However, it is still concerned to use in practice due to the lack of analysis of the performance factors affecting the UAS-based facility condition inspection. Hence, the purpose of this study is to identify the critical factors as well as their correlations by modeling causal loop diagram (CLD). A total of 20 variables were derived in four categorized groups, and the relationships were analyzed. Further study will develop a system dynamics (SD) model to simulate various scenarios based on stock-flow diagram through the defined relationships in this study.

• Korean Journal of Social Welfare
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• v.65 no.2
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• pp.203-230
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• 2013

The present study aimed to analyze possible causal relationship between drinking problem and depression. In addition, The study examined if poverty status transition is associated with the causal relationship between drinking problem and depression. The study sample consisted of 3,976 adults who have participated in both the first and the second wave survey of the Korea Welfare Panel Study. The causality between drinking problem and depression was analyzed using Latent Difference Scores (LDS) model, which was established in McArdle & Hanagami (2001). Furthermore, it was examined if poverty status transition (represented by four subgroups: poverty-sustained group, poverty-escaping group, non-poverty-sustained group, poverty beginning group) would influence the causal relationship between drinking problem and depression. The major findings are as follows. The result of a LDS model analysis using the entire sample shows that depression at the first wave predicts significantly the change of drinking problem between the first wave and the second wave and also drinking problem at the first wave predicts significantly the change of depression between the first wave and the second wave, which can be interpreted as there is reciprocal causal relationship between depression and drinking problem. In poverty status transition subgroup analyses, the reciprocal causal relationship between depression and drinking problem is held in the poverty-sustained group while depression is a cause of drinking problem both in the poverty beginning group and in the non-poverty-sustained group. However, there is no significant causal relationship between depression and drinking problem in the poverty-escaping group. All these findings indicate that the direction of causality between depression and drinking problem can be varied according the poverty status change, which provides a comprehensive explanation to inconsistent research findings from previous cross-section studies of the relationship between depression and drinking problem.

• Korean Journal of Cognitive Science
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• v.27 no.4
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• pp.541-572
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• 2016

Causal reasoning is actively studied not only by psychologists but, in recent years, also by cognitive scientists taking the Bayesian approach. This paper seeks to provide an overview of the recent trends in causal reasoning research with a focus on the power probabilistic contrast theory of causality, a major psychological theory on causal inference. The power probabilistic contrast theory (PPCT) assumes that a cause is a power that initiates or inhibits the result. This power is purported be understood through statistical correlation under certain conditions. The paper examines the supporting empirical evidence in the development of PPCT. Also, introduced are the theoretical dispute between the PPCT and the model based on Bayesian approach, and the current developments and implications of research on causal invariance hypothesis, which states that cause operates identically regardless of the context. Recent studies have produced experimental results that cannot be readily explained by existing empirical approach. Therefore, these results call for serious examination of the power theory of causality by researchers in neighboring fields such as philosophy, statistics, and artificial intelligence.

• 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.

• Journal of Information Technology Services
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• v.6 no.1
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• pp.47-63
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• 2007

A lot of researchers have been interested in the factors influencing the use of mobile phone services. Most of the previous studies, however, verified only the research models developed by the authors. They did not consider which model agrees better with the real situation. This study presents six alternative models based on various previous studies, and compares the data fitness of the models. A Web survey of mobile phone users collected 2,217 cases. Statistical analyses, using SEM (Structural Equation Modeling), show that the fitness of the simplest alternative model is better than that of any other model. The simplest model has no causal relationship among exogenous factors, and proposes that all of exogenous factors have direct impacts on the customer satisfaction. In addition, the analyses say that corporate and brand image and additional service are more important than the other exogenous factors such as communication quality.

• Journal of Korea Trade
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• v.25 no.2
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• pp.178-195
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• 2021

Purpose - This study aims to analyze consumer in the multidimensional aspect of a combination of corporate image and brand personality in order to identify the structural causal relationship between consumer choice and corporate image and brand personality. Design/methodology - This study combined theoretical literature studies with empirical field studies using questionnaire survey methods. To achieve this objective, a hypothetical causal model consisting of three potential variables and nine measurement variables was created based on prior research, and a structural equation model was used to identify the suitability of the model. Findings - The hypothetical model established by this study was judged to be generally appropriate. In particular, corporate image was shown to have significant static direct effects on consumer choice and brand personality. It was also shown that brand personality had a direct static effect on consumer choice, and that corporate image has an indirect significant impact on consumer choice by moderating brand personality. Originality/value - Previous papers have mainly focused on one-dimensional studies of various images, such as companies and brands. However, this paper used a model that analyzed consumer choice through multi-clue information rather than corporate images as the only clue to consumer choice.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.3
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• pp.383-397
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• 2012

In this study, a System Dynamics (SD) simulation model for the efficient operations of an industrial water supply system was developed by investigating the feedback loop mechanisms involved in the operations of the system. The system was modeled so that as demand is determined the water supply quantity of intake pumping stations and dams are allocated. The main feedback loop showed that many variables such as the combinations of pump operation, unit electric power(kWh/$m^3$), unit electric power costs(won/$m^3$), water level of water way tunnel, suction pressure and discharge of pumping station, and tank and service reservoir water level had causal effects and produced results depending on their causal relationship. The configurations of the model included an intake pumping station model, water way tunnel model, pumping station model (including the tank and service reservoir water level control model), and unit electric power model. The model was verified using the data from the case study industrial water supply system that consisted of a water treatment plant, two pumping stations and four dams with an annual energy costs of 5 billion won. It was shown that the electric power costs could have been saved 7~26% during the past six years if the operations had been based on the findings of this study.

• Korean Journal of Human Ecology
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• v.17 no.1
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• pp.141-150
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• 2008

The purpose of this study was to assess the causal relationships among hedonic belief, ambivalence, subjective norm, attitude and meat consumption behavior. A total of 318 questionnaires were completed. Structural equation model was used to measure the causal effects of constructs. Results of the study demonstrated that fit of the restricted baseline model is significantly worse than that of the unrestricted proposed model, in which more parameters are estimated. The effects of hedonic belief, ambivalence and subjective norm on attitude were statistically significant. The effects of hedonic belief, subjective norm and attitude on meat consumption were statistically significant. The effect of attitude on intention was statistically significant. Moreover, attitude played a mediating role in the relationships between hedonic belief and meat consumption, between ambivalence and meat consumption, and between subjective norm and intention. This study suggested that the consumer decision-making process for eating meat products is best modeled as a complex system that incorporates both direct and indirect effects on meat consumption. This study believed the evidence presented supports this position. Moreover, this study appeared to be a worthy area of pursuit.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.3
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• pp.417-424
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• 2007

The purpose of this study was to measure the effects that service quality, perceived value and satisfaction have on loyalty in Namhaean area restaurants. A total of 273 questionnaires were completed. The structural equation model was used as an analysis method to measure the causal effects of service quality, perceived value, satisfaction and loyalty. The results demonstrated that the structural analysis result for the data was an excellent model fit. The effect of service quality on value, the effect of perceived sacrifice on value, the effect of service quality on satisfaction, the effect of value on satisfaction, and the effect of satisfaction on loyalty were statistically significant. Moreover service quality had an indirect effect on satisfaction through perceived value, and service quality also had an indirect effect on loyalty through perceived value and satisfaction. Perceived value had an indirect effect on loyalty, and an effect through satisfaction. Perceived sacrifice had an indirect effect on satisfaction through perceived value, and it also had an indirect effect on loyalty, and an effect through satisfaction. Further study is still required, and should be aimed at identifying the causal mechanisms of constructs, such that restaurant managers might be better prepared to offer value and satisfaction to their customers.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.3
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• pp.304-311
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• 2007

The purpose of this study was to measure the causal relationships among fish consumption behavior, attitude towards fish eating, health involvement, perceived convenience, and age. A total of 235 questionnaires were completed. A structural equation model was used to measure the causal effects of the constructs. The results of the study demonstrated that the structural analysis results were an excellent model fit for the data. The influence of age on attitude towards fish eating, health involvement, and perceived convenience was statistically significant. As expected, attitude towards fish eating, health involvement, and perceived convenience had significant effects on fish consumption behavior. Moreover, age had a significant indirect effect on fish consumption behavior through health involvement. Age also had a significant indirect effect on fish consumption behavior through perceived convenience. By developing and testing conceptual models that integrate the relationships among age, psychological variables, and fish consumption behavior, this study may offer a deeper understanding of the complex relationships among the variables. A greater understanding of these complex relationships can improve the managerial diagnoses of problems and the opportunities for different marketing strategies, including product development and marketing communications.