• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.249-250
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• 2002

In this paper, the relationship among the 3-D surface topography parameters are studied. Several surface topography parameters that are important in tribology are calculated against various surface topography data. 3-D surface data with desired properties are generated by using the non-causal 2-D auto-regressive (AR) model. The non-causal 2-D AR model is a random 3-D surface topography model that can generate 3-D surface topography data with specified parameters.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.1
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• pp.1-8
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• 2009

This paper aims mainly to reinterpretate Optimal Bus Scheduling Model by applying System Dynamics Perspective. Traditionally, the study regarding Optimal Bus Scheduling Model stems on the linear relationshp. However, this paper attempted to convert linear relationship based Optimal Bus Scheduling Model to causal loop perspective based Model. In result, the paper present Casual Loop Diagram for Optimal Bus Scheduling Model. Furthermore, the paper also ran a simulation based on Stock & Flow Diagram for Optimal Bus Scheduling Model. The outcome was not much different from the linear relationship based Model due to the similarity of the equation applied on two models.

• Journal of the Korean earth science society
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• v.30 no.1
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• pp.111-126
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• 2009

The purpose of this study was to derive the criterions of each type of mental models on the plate boundaries and to investigate high school students' mental models on these concepts. The 11th grade student participants were requested to draw the collisional, convergent, and divergent boundaries and were interviewed individually. The drawings and the data gathered through the interviews were analyzed qualitatively. The mental models on the plate boundaries were classified as 'naive model', 'unstable model', 'causal model', and 'conceptual model'. The criterions for analyzing the mental models were the differentiations of the lithospheric plates and the mantle, the explanations of the motion of the plates and lower mantle, the demonstrations of topographical features of the plate boundaries and the causal relationships between the mantle convection and the topographical features. The findings revealed that the students holding 'the naive model' and 'the unstable model' were unable to relate the mantle convection and the three boundaries. In contrast, the students holding 'the causal model' and 'the conceptual model' were able to explain that the mantle convection causes the three boundaries. Also, the types of epistemological belief were different depending on their mental models. Students holding the naive model and the unstable model tended to rely upon the external authorities.

• Journal of the Institute of Convergence Signal Processing
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• v.5 no.2
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• pp.151-158
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• 2004

In this paper, an inverse filtering technique for the digital filter model is proposed. This technique enables us to obtain a stable non-causal m inverse filter by transforming (approximating) it to a causal stable inverse system. In practice, a causal FIR approximation to this inverse filter is proposed. It can be shown that the impulse response of the inverse filter for all-pass systems is simply the mirror image of the impulse response for the system. Specially, due to this symmetric property of the impulse response of all-pass systems, the proposed technique is more useful for all-pass systems than other systems. In order to illustrate the proposed inverse filtering technique, four examples are presented. Two of them are for all-pass filters. The other two examples are for IIR and FIR filters. Also, computer simulations demonstrate that the proposed technique works very well.

• Health Policy and Management
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• v.5 no.2
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• pp.173-201
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• 1995

A causal model of organizational commitment on the basis of Western literature was tested with a sample of 1,164 employees from two university hospitals in Korea. The model contains three groups of determinants : environmental variables(job opportunity, spouse support, and parent support), psychological variables(met expectations, work involvement, positive affectivity, and negative affectivity), and structural variables(job autonomy, work unit control, routinization, supervisor support, coworker support, role ambiguity, role conflict, workload, resource inadequacy, distributive justice, promotional chances, job security, job hazarda, and pay). The data were colleted with questionnaires and analyzed with the LISREL maximum likelihood method. It is found that (1) the following variables, listed in order of size, have significant total effects on organizational commitment : job satisfaction, met expectations, supervisor support, job security, routinization, job opportunity, negative affectivity, work involvement, distributive justice, and promotional opportunity, (2) the model explains fifty-nine percent of the variance in organizational commitment, and (3) the link with expectancy theory is justified by the results for met expectations. Two conclusions can be drawn from these findings. First, the model of organizational commitment appears to be generalizable to Korean hospitals. Second, the model of organizational commitment should include such theoretical variables as environmental, psychological, and structural factors.

• Culinary science and hospitality research
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• v.14 no.2
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• pp.170-180
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• 2008

The purpose of this study was to measure the causal relationships between past consumption, health belief, subjective, attitude, intention and purchase of organic foods. Total 326 copies of questionnaire were completed. The structural equation model was used to measure the causal effect among constructs. The results demonstrated that the confirmatory factor analysis model provided a good model fit. The proposed model yielded a significantly better fit to the data than the baseline model and the extended model. The effects of past consumption, health belief and subjective norm on attitude and intention were statistically significant. The effects of attitude on intention and behavior to purchase organic food were statistically significant. As expected, health belief and subjective had significant effects on behavior to purchase organic foods. Moreover, past consumption, health belief and subjective norm had indirect influences on intention through mediated variables. Based on the empirical results and findings, some suggestions are provided to the institutions concerned so as to facilitate this organic sector's on-going expansion in the food industry.

• Journal of the Korean Home Economics Association
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• v.32 no.3
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• pp.171-184
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• 1994

This study examined the characteristics of the relationship of environmental variables that is HOME socio-demographic variables and children's verbal ability at age five. Especially this study investigated causal relationships among the variables which are supposed to affect children's verbal ability. The subjects of this study were 60 children at age five and their mothers. Instruments included inventory of home stimulation(HOME) inventory of socio-demographic variables inventory of the children's verbal ability and intelligence test. The results obtained from study were as follows: 1. For the most part environmental variables had a significant positive correlation with children's verbal ability 2. The variables that significantly predicted boy's verbal ability were aspects of physical environment breadth of experienc. And the variables that significantly predicted girls' verbal ability were developmental stimulation economic status of the home. 3. The results of the analysis of the causal model showed that the kind of variables that affected boy's verbal ability directly were indirect stimulation direct stimulation. And the kind of variables that affected girls' verbal ability directly were direct stimulation econmic status of the home inditect stimulation. 4. Another causal model of the environmental variables affecting children's verbal ability were formulated by exogenous variables(socio-demographic variables) and by endogenous variables (HOME, children's intelligence). The results of the analysis of the causal model showed that only HOME variables significantly affected boy's and girls' verbal ability directly.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.5
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• pp.365-376
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• 2022

This study aims to look into the causal relationships between corporate social responsibility and firm value, corporate social responsibility and institutional ownership, and firm value and institutional ownership. This study develops a triangle model of causal relationships among the three endogenous variables. Samples for this study are manufacturing companies listed on the Indonesia Stock Exchange for the period 2014-2018. The model is operated in the system of simultaneous equation models using the generalized method of moments technique to estimate parameter coefficients. After controlling the effects of trade-off/balancing capital structure and managerial ownership, the research findings show a positive causal relationship between CSR and firm value and firm value and institutional ownership. Institutional ownership has a positive effect on CSR, while the effect of CSR on institutional ownership is negative in the firms without managerial ownership and positive in the firms with managerial ownership. This study finds that the causal relationship between CSR and firm value is stronger after the trade-off/balancing of capital structure is included in the model. Capital structure has a convex effect on firm value and positively impacts institutional ownership. In addition, an independent commissioner has a negative impact on CSR but has no direct impact on firm value.

• Korean Journal of Human Ecology
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• v.16 no.5
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• pp.1031-1040
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• 2007

The purpose of this study was to assess the causal relationships of attitude toward fish eating, health involvement, convenience, fish consumption and age. A total of 235 questionnaires were completed. Structural equation model was used to assess the causal relationships among constructs. Results of the study demonstrated that the structural equation analysis result for the data also indicated excellent model fit. The influences of age on health involvement and convenience were statistically significant. The influences of health involvement on attitude toward fish eating and fish consumption behavior were statistically significant. The influence of convenience on fish consumption behavior were statistically significant. Moreover, the age had a significant indirect effect on attitude toward fish eating through health involvement. The age also had a significant indirect effect on fish consumption behavior through convenience.

• Journal of the Korean Institute of Landscape Architecture
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• v.20 no.3
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• pp.103-109
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• 1992

This research suggest a causal model to investigate factors and variables which significant effects on user satisfaction with city park recreational facilities in Duryu city park in Taegu, and thereby identifying implications for planning and development of urban parks and open space. For this study the data were gathered by self-adminstered questionnares from 993 households selected by the multi-stage probability sampling method. The analysis of the data consists of two phases. The first involves exploratory factor analysis to draw meaningful factors from the data. Three factors were indentified. The second phase test the causal model of this research employing LISREL methodology. On the base of the analysis results, important implications for planning of city park and open space are recommended.