• 대한전기학회논문지:전력기술부문A
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• 제48권6호
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• pp.665-670
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• 1999

This paper introduces a fuzzy expert systems for fault diagnosis, where the causal relationships between faults and protective devices are defined as fuzzy relations. The uncertainties existing in the fault diagnosis are figured out using the possibility theory and the possibility measure is associated with the fuzzy relation to evaluate the possibilities of faults. Besides, the knowledge base in the expert system is described and explained. In this way, multiple-fault can be handled easily and simultaneously together with single faults.

• 한국조리학회지
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• 제14권4호
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• pp.93-105
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• 2008

This study was attempted to analyze causal relations among flexibility, growth, and profitability variables, which are the financial indexes of restaurant enterprises. The samples were 24 restaurant enterprises in total, and 102 financial statements between 2002 and 2006 were analyzed. As a result of the analysis, total asset growth rate influenced all profitability variables among growth variables. Also, the net sales growth influenced return on sales and return on assets, and the assets turnover influenced return on assets and return on equity. Among flexibility variables, current ratio and interest coverage ratio to operating profit influenced return on assets, and return on equity was influenced by current ratio and debt-to-equity ratio.

• 전자공학회논문지B
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• 제32B권12호
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• pp.1687-1696
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• 1995

An integrated fault diagnosis system for heterogeneous manufacturing environments is developed. This system has a contrast with existing diagnosis systems in the respect that they are mostly for diagnosing faults on individual machines. In addition to the usual (e.g., audio, electrical) diagnostic signals, the characteristics of products from the machines are considered as the unifying diagnostic parameters among heterogeneous machines in the diagnosis. The system is composed of a knowledge representation scheme and a diagnostic query processing mechanism. Its knowledge representation scheme allows the diagnostic knowledges from heterogeneous unit diagnostic systems to be uniformly expressed in terms of the causal relations among relevant data items. It is flexible in the sense that causes for one relation can be effects for another may be reflected on our knowledge representation scheme. The diagnosis mechanism is based on a probabilistic inferencing method. This probablistic diagnosis mechanism provides more general diagnosis than existing ones in that it accommodates multiple causes and takes complication among causes into account. These scheme and mechanism are applied to a typical example to demonstrate how our system works.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.169-174
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• 2005

The purpose of this study is to investigate the influence of perceived job insecurity, organizational commitment, and social climate on safety behavior and accidents. The research on this subject was conducted in the Korean National Railroad. The cross-level model was hypothesized to study causal relations among these variables. The cross level model combines individual level approach with group level approach. In this model supervisors(group level) affect organizational commitment(individual level) and at the same time safety climate(group level) influences safety behavior(individual level) positively. Traditionally operators have been blamed as accident causer. This study, however, shows that organizational and systematic factors are as much critical factors determining safety behavior and accidents.

• 아동학회지
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• 제28권2호
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• pp.19-37
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• 2007

In this study of the relative effectiveness of constructivist and non-constructivist approaches to shadow activity for young children, 59 children in two kindergarten classes were assigned to constructivist or non constructivist conditions. Each group participated in 12 units covering shadow search, shadow making, changing shadow size, changing shadow position, and shadow disappearance. Analysis of covariance of differences between the mean scores of the two groups on the posttests of shadow concepts and scientific attitudes revealed that the children in the constructivist group performed better than the children in the non-constructivist group. This confirms the constructivist approach to shadow activities as good science activities for young children by promoting their active experimentation using reasoning about light to foster spatio-causal relations construction.

• 아태비즈니스연구
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• 제6권2호
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• pp.63-79
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• 2015

The purpose of this study is to examine the effects of transformational leadership on job satisfaction and to examine the effects of transactional leadership on job satisfaction. This study tried to verify the facial feedback hypothesis in causal relations of charisma, intellectual stimulation, individualized consideration, contingent reward, management by exception, job satisfaction. The self-administerd survey was undertaken against 380 respondents who soldier working in Daegu. A total of 375 responses were collected. Excluding missing data, 337 usable data were used for analysis. Results of this study are as follows. First, it is found that charisma factor is positively impact on job satisfaction. Second, it is found that individualized consideration factor is positively impact on job satisfaction. Third, it is found that contingent reward factor is positively impact on job satisfaction. Fourth, it is found that management by exception is positively impact on job satisfaction. The theoretical implication and practical implication for the army and government are discussed. The limitations are also mentioned.

• 한국시스템다이내믹스연구
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• 제12권1호
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• pp.39-57
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• 2011

This paper is the result of simulation modeling concerning high-level radioactive waste repository(HLRWR) and people's mind for the facility. We describe a procedure of simulation modeling for resident's policy acceptance and perceived risk of HLRWR facility by using System Dynamics approach. To Complete some complicated works, we made the 20 pieces of stock-flow diagrams based on the causal loop diagram that is a blue print of whole variables and relations. The simulation outputs clearly show that cental government efforts to siting the HLRWR will be failed if nothing to give for the region's residents. On the contrary, a monetary incentive and a regional development program help to turn this gloomy situation into a desirable and acceptable condition dramatically. Government has to prepare the schemes considering the HLRWR acceptance and total supporting program including the cash and local development programs.

• 한국시스템다이내믹스연구
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• 제12권1호
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• pp.59-74
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• 2011

This article deals with an economic evalutation of the 'Pasture Project of Kum River', which is the farming plan of mitten crabs in a stream of it. An augmented model of social capital is based on the past ecological-economic system dynamics model and elaborated further with suggestions of social capital literature. During the modeling process a chain diagram of causal relations and its relevant mathematical equations are presented for simulating the project performance, and the simulation results are provided to contrast the dynamic behaviors of the former ecological-economic model with ones of the new model incorporating social capital. The results indicate that an increase in the economic benefit of the project could happen in case of considering the process of social capital accumulation around the case area, which can be regarded as a remarkable trial to approve the common confidence in the role of social capital to enhance an economic achievement.

• Communications for Statistical Applications and Methods
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• 제9권1호
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• pp.141-154
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• 2002

Foreign investors'shares and their influences on the Korean stock market have never been larger and greater before since the market was completely open to foreign investors in 1992 Quantitatively and qualitatively as well, as a result, changes in the patterns of foreign investments have caused enormous effects on the interactions of major macroeconomic indices of the Korean economy. This paper is intended to investigate the causal relations of the four variables, foreigners'buy-sell ratios, stock returns, ￦/＄ exchange rates and $\yen$/＄ exchange rates, over the two time periods of the pre-IMF (1996.1.1-1997.8.15) and the post-IMF (1997.8.16-2000.6.15) based on the daily data of the variables. Granger Causality Test, Forecast Error Variance Decomposition(FEVD) using VAR model and Impulse Response Function were implemented for the empirical analysis.

• 한국조리학회지
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• 제13권2호
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• pp.174-187
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• 2007

The purpose of this research is to analyse the cause and effect relations among management strategies, performance assessment and management performance in the hotel industry. The research result is as follows. A management strategy of the hotel industry has influence directly on a performance assessment through the non-financial factor, the financial factor and the study evaluation factor. And a financial performance assessment and a non-financial performance assessment have influence directly on the management performance. Total effects on a management performance of the hotel industry were 0.769 in a management strategies and 1.755 in a performance assessment. In comparison in the direct effects, the management strategies do not influence the management performance directly, and management performance is revealed through a performance assessment.