• 한국시뮬레이션학회논문지
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• 제4권2호
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• pp.31-40
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• 1995

A hybrid simulation model consists of real physical entities as well as simulated ones. It also contains logical processes for decision making for each operation units, a group of the entities. During the execution of such simulations, the physical and the logical processes consume real clock time while the activity durations of the simulated ones are generated. Due to the inherent chracteristics of the subjects of the communication channels. Since one can not undo an real event already taken place, the traditional central clock approach is used for the synchronization of the events(Kim[6]). However, there are still chances of causality errors due to the randomness in the communication delays. This error is not found in the distributed pure simulations. This paper explains the error in details and proposes a prevention scheme that is simple to implement.

• 한국소음진동공학회논문집
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• 제15권10호
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• pp.1131-1136
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• 2005

For the accurate measurement of acoustic properties of a surface, efforts have been made to reduce errors caused by external disturbance. If the reflection coefficient is considered as a transfer function between reflected wane and incident wave, the causality is required between them and the reflection coefficient should be of minimum phase. In this thesis, the minimum phase condition is applied to measure correct reflection coefficient. The reflection coefficient is approximated as a rational function In the Z domain by minimizing the sum square error. Then the minimum phase reflection coefficient is reconstructed using the distribution of poles and zeros of the reflection coefficient model.

• 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.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 1999년도 추계종합학술대회
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• pp.60-65
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• 1999

본 논문은 정보통신 표준화의 경제적 효과를 분석하기 위한 기초 연구의 일환으로 정보통신 표준화 분야 연구 투자가 국가 경제발전 특히 정보통신 산업매출액과의 인과관계를 Granger Causality 통하여 분석하였다. 분석 결과 정보통신 표준화 연구 투자가 정보통신 산업매출액 추이 보다 선행함을 통계적으로 증명함으로써 국가경제 발전을 위한 정보통신 표준화 연구 투자가 선행되어야 한다는 정책적 참의를 도출하였다.

• 국제지역연구
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• 제20권1호
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• pp.127-146
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• 2016

This paper investigates that the Granger-causality between ODA FDI Trade, and economic growth in Senegal over the last 50 years and ODA, FDI, Trade have a impact on the Senegal's economic growth using the Vector Error Correction Model. The empirical results do confirm a directional causality between the variables considered. It also showed that an increase of ODA in the Senegal has positive effect on GDP growth and FDI, which are important factors of economic growth for poor country like Senegal. Underdeveloped nation has been suffered from insufficient savings or capital for economic growth; therefore, developed nations have to provide enough ODA to supply initial capital formation for growth, so-called, seed money. In a nutshell, ODA as a priming the pump is required and expanded continuously for Africa country's economic growth.

• 아태비즈니스연구
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• 제12권4호
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• pp.53-61
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• 2021

Purpose - The purpose of this paper is to assess the empirical evidence that shows blockchain technology has been a significant contributor to the growth of maritime transport in the shipping industry. Design/methodology/approach - Employing a generalized linear model using data from 2010 to 2019, this paper presents empirical evidence to demonstrate the positive impact of the adoption of blockchain technology on the maritime transport industry. Findings - Results from Granger causality tests confirm that there is a positive unidirectional causality from blockchain technology to maritime transport. This paper also demonstrates the positive effects of information technology (IT) and GDP growth on maritime transport. On the other hand, maritime transport is negatively influenced by the tax burden. Research implications or Originality - The results of this paper suggest a potential sustainable development strategy for the maritime transport industry involving the redirection of economic resources toward blockchain technology. Adopting other forms of IT and reducing the tax burden are also useful strategies for the development of the industry.

• 경영과학
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• 제25권3호
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• pp.13-26
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• 2008

We investigate the effect of government and public sector R&D Investment at IT Industry on the amount of Production, export and nongovernment R&D Investment at IT Industry. We, firstly, examine the stationarity of each variable by the unit root t-test and perform the co-integration test for the pairs of variables. We use YECM(Vector Error Correction Model) according to the results of co-integration test for the examination of Granger-causality between variables. It is found that there exist an Granger-causality between public sector R&D Investment and nongovernment R&D investment and also between public sector R&D Investment and export. Secondly, we analyze the impulse response of government and public sector R&D Investment at IT Industry on the amount of production, export and nongovernment R&D investment at IT Industry based on VECM model. It is found that the response of the amount of production is highest at 3th period and is lowest at 8th period and that of export shows similar pattern.

• Journal of Preventive Medicine and Public Health
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• 제35권3호
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• pp.236-244
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• 2002

Objective : To empirically investigate the relationship of internal and external customer satisfactions, service quality, and customer loyalty in medical services. Methods : This essay proposes an integrated model to explain the causality of internal and external customer satisfactions, service quality, and customer loyalty. To this end, a structural model was developed, consisting of the following factors: internal and external customer satisfactions, service quality, and customer loyalty. The study included 214 sets of data, with 107 sets being collected for both out-patients and in-patients. The data were analyzed using AMOS 4.0. Results : We found the greater the internal customer satisfaction, the greater the out-patient quality of service quality. Secondly, the greater the service quality, the greater the external customer satisfaction of both in- and out-patients. The service quality of doctors, compared to that of the nurses, had a greater effect on external customer satisfaction. Thirdly, the service quality of doctors and nurses affected both internal and external customer satisfactions, which ultimately affected the customer loyalty. Finally the greater the external customer satisfaction, the greater the customer loyalty. Conclusion : This Study confirms the positive relationship among the internal and external customer satisfactions, service quality, and customer loyalty, which proves the doctors quality of service is the primary factor for external satisfaction, and customer loyalty relating to medical services.

• The Journal of Asian Finance, Economics and Business
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• 제7권8호
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• pp.533-542
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• 2020

This study estimates the nature of the relationship of entrepreneurship and business confidence on youth unemployment in the Philippines over the 2001-2017 period. The paper employed a range of cointegrating regression models, namely, autoregressive distributed lag (ARDL) bounds testing approach, Johansen-Juselius (JJ) and Engle-Granger (EG) cointegration models, dynamic OLS, fully modified OLS, and canonical cointegrating regression (CCR) estimation techniques. The Granger causality based on error correction model (ECM) was also performed to determine the causal link of entrepreneurship and business confidence on youth unemployment. The ARDL bounds testing approach, Johansen-Juselius (JJ) and Engle-Granger (EG) cointegration models confirmed the existence of long-run equilibrium relationship of entrepreneurship and business confidence on youth unemployment. The long-run coefficients from JJ and dynamic OLS show significant long-run and positive relationship of entrepreneurship and business confidence on youth unemployment. While results of the long-run coefficients from fully modified OLS and canonical cointegrating regression (CCR) found that only entrepreneurship has significant and positive relationship with youth unemployment in the long-run. The Granger causality based on error correction model (ECM) estimates show evidence of long-run causal relationship of entrepreneurship and business confidence on youth unemployment. In the short-run, increases in entrepreneurship and business confidence causes youth unemployment to decrease.

• 유통과학연구
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• 제20권8호
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• pp.105-114
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• 2022

Purpose: The technology acceptance model (TAM) refers to a theory that maps the possibility or extent to which users can accept an innovative technology. The purpose of the current research is to investigate the mediating effect of TAM between online review and behavior intention for promoting golf app's distribution. Research design, data and methodology: In order to examine the relationship between app usage reviews, TAM, and behavioral intentions of golf app participants, the present author collected total 170 responses from South Korean participants based on web-based survey system. The main methodology which was selected by this study is mediation causality analysis that Baron and Kenny suggested. Results: The statistical findings definitely indicated that TAM mediating role exists between the positive emotion of golf app users regarding online reviews and positive behavior intention of golf app, which means that all three steps of mediation causality analysis were statistically significant. Conclusions: The present research concludes that the correct utilization of innovation in the design and implementation of the technology features translates into performance excellence. The model can be used to increase the online presence through innovation as a primary drive toward providing more convenience and accessibility to the users through mobile golf apps.