• Transactions on Control, Automation and Systems Engineering
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• v.1 no.1
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• pp.62-68
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• 1999

FCM(Fuzzy Cognitive Map) is proposed for representing causal reasoning. Its structure allows systematic causal reasoning through a forward inference. Authors have already proposed a diagnostic system based on FCM to utilized to identify the true origin of fault by on-line pattern diagnosis. In FCM based fault diagnosis, Temporal Associative Memories (TAM) recall of FCM is utilized to identify the true origin of fault by on-line pattern match where predicted pattern sequences obtained from TAM recall of fault FCM models are compared with actually observed ones. In engineering processes, the propagation delays are induced by the dynamics of processes and may vary with variables involved. However, disregarding such propagation delays in FCM-based fault diagnosis may lead to erroneous diagnostic results. To solve the problem, a concept of FTCM(Fuzzy Time Cognitive Map) is introduced into FCM-based fault diagnosis in this work. Expecially, translation method of FTCM makes it possible to diagnose the fault for some discrete time. Simulation studies through two-tank system is carried out to verify the effectiveness of the proposed diagnostic scheme.

• Journal of Korean Elementary Science Education
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• v.37 no.1
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• pp.1-11
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• 2018

Factors and causal structures of pre-service elementary teachers about the critical thinking and the scientific literacy competency were investigated in this study. The third grade university students and the first grade university students in the metropolitan city participated in this study. The factor analysis method and the structural equation modeling method were used for the data analysis, and the following results were obtained. First, the third grade university students and the first grade university students recognized 'inquisitive thinking' factor and 'reflective thinking' factor as factors of the critical thinking, and 'scientific explanation' factor and 'evidence-based conclusion' factor as factors of the scientific literacy competency respectively. Second, the third grade university students showed more the influence from 'reflective thinking' factor to 'scientific explanation' factor and from 'reflective thinking' factor to 'evidence-based conclusion' factor than the first grade university students.

• Korean System Dynamics Review
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• v.12 no.1
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• pp.89-114
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• 2011

With steady increase in the demand for door-to-door delivery services, courier service providers are facing a constant pressure to reduce delivery price in order to secure quantity order and to improve the efficiency and reliability for customer service. The objective of this research is to explain the structure of the door-to-door delivery including door-to-door delivery service demand, sorting capacity in the hub-terminal, and the system performance measures such as service reliability networks using causal loop diagram(CLD). Based on causal relation, this research describes a comprehensive approach to examine how capacity reliability contributes to the renewal of the firm's competences through its reciprocal relationship with travel time reliability and connectivity reliability. Also, this research suggests the policy alternatives to improve effectiveness and efficiency of door-to-door delivery network in response to increase customer satisfaction and profit maximization of the courier service providers: operational, tactical, and strategic levels.

• Journal of Families and Better Life
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• v.14 no.1
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• pp.35-46
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• 1996

This study was designed to investigate causal relationships among related variables that determined psychological distress of aged mothers. In this study questionaires were used to measure and subjects were 244 mothers aged over 60 and lived in K city. 221 answers were analyzed by SAS and covarince structure analysis. The results were as follows: it was found that pocketmoney and health had direct effects on objective solidarity education level pocketmoney and activity on subjective solidarity marital status and health on psychological distress between exogenous variables and endogenous variables. Among endogenous variables objective solidarity had direct effects on subjective solidarity and self-esteem subjective solidarity on self-esteem and self-esteem on psychological distress respectively. Subjective solidarity was found to be most effectable variable on psychological distress.

• Korean Journal of Child Studies
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• v.27 no.3
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• pp.271-284
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• 2006

In order to define their relative influence, this study analyzed causal relationships between academic achievement of elementary school students and such related variables as self-esteem and the psychological and economic environment of the home, including clarification of other significant variables affecting academic achievement. Participants were a sample of 485 5th grade students from 8 elementary schools in Busan. Correlation, analysis of covariance structure modeling, and model-fitness tests were applied to the data. Results indicated that the psychological environment of the home has the most significant influence on the academic achievement of children, and the economic environment of the home and self-esteem have relatively low or indirect influence.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.10
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• pp.97-104
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• 2022

The purpose of the existing work is to inspect the impact of knowledge management on organizational performance. Business experts now appreciate how important knowledge management is for organizational performance. Earlier studies have investigated the research model with causal linkages, however, only a few of them have considered sample-selecting bias problems when analyzing the model of knowledge management on organizational performance. The number of 312 executives related to knowledge management from 312 enterprises that have been approved with quality management systems offered suitable responses for analyses. The data was employed to investigate the effect of knowledge management on organizational performance, considering sample-selecting bias. The empirical outcomes indicate that sample-selecting bias exists in the causal impact of knowledge management on organizational performance. The empirical findings are helpful to scholars of knowledge management as well as business executives by giving an insight into the casual effect of knowledge management on organizational performance with the intervention of sample-selecting bias. The acceptance of knowledge management should be tailored to improve competitive advantages that will lead to better organizational performance.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.36 no.4
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• pp.213-221
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• 2018

South Korea has been reluctant to open its geospatial information overseas to ensure security as a divided country. However, this cannot continue as the domestic and international environments related to geospatial information and the industrial ecosystem of information and communication technologies have been changing dramatically. Within this context, this study aims to analyze the causal relations among relevant variables and how they change and interact with time using a systems thinking process. First, causal maps were created for the domains of national security, map-based convergence service, and corporate competition. Then, the causal maps for each domain were integrated, based on which the points for policy intervention and dominant feedback loops were identified. The analysis results showed that securing the self-sufficiency of domestic geospatial businesses is a key element to determine the whole causal map, and the variable that changes the dominant feedback loop from a vicious circle to a virtuous one is the decision to open geospatial information overseas. In this study, I found the policy leverage that is a policy intervention point that can produce a great effect with little input by building a causal map of the interactions between major variables. This study is significant in that it identified and analyzed the dominant feedback loop as to which causal structure would dominate the system in the long term. The results of this study can be used to discuss not only the impacts of map data overseas opening on the national security and geospatial information industry, but also the interactions in the future when Google or other global companies request to release the geospatial information.

• Journal of the Korean Operations Research and Management Science Society
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• v.33 no.2
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• pp.153-174
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• 2008

There have been two streams of the studies on development structure : conceptual model approach and statistical analysis approach. But In these days, the latter has been becoming the main approach owing to the development of multivariate statistical methods and statistical packages. In this study, we examine methodologies and results of the leading researches related to development structure based on statistical analysis and propose the future research directions. This analysis would be expected to contribute toward the construction of long-range development policies on each country.

• Journal of Agricultural Extension & Community Development
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• v.23 no.4
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• pp.431-439
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• 2016

There are rural development policy for creating liveable rural. The support structure of the capacity phase of the Master Plan of Comprehensive Rural Village Development Project would that one. The support structure of the capacity phase has implied the assumption that the accumulated capacity of the village to the previous step will have a significant impact on the business to the next level. Rural development should be understood that simple: rather than for business applications, processes community is going to build capacity through continuous learning and practice. Its accumulated capacity should be possible to predict and then steps must be developed continuously for a long time, looking at the previous phase. Thus, according to the support structure of the capacity phase, it should be applied a causal relationship between the front and rear phase.

• Membrane Journal
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• v.30 no.4
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• pp.205-212
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• 2020

This short review focuses on fouling by proteins and macromolecules in microfiltration/ultrafiltration. First, an experimental system that enables investigation of how the extent of the adsorption of proteins and macromolecules on membrane surfaces contributes to a decrease in filtrate flux in microfiltration/ultrafiltration is described. Using this system, a causal relationship - not a correlation - indicating that adsorption results in a decrease in filtrate flux could be clearly demonstrated in some cases. Second, a hydration structure at the membrane surface that can suppress adsorption is discussed, inspired by biomaterial research. In their hydrated states, polymers with low-fouling properties have water molecules with a particular structure. Finally, some successful examples of the development of low-fouling membranes via surface modification using low-fouling polymers are discussed.