• Korean Journal of Agricultural Science
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• v.50 no.3
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• pp.331-347
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• 2023

The downstream submergence damages caused during the flood season in 2020, around the Yongdam-dam and five other sites, were analyzed using related dam management data. Hourly- and daily-data were collected from public national websites and to conduct various analyses, such as autocorrelation, partial-correlation, stationary test, trend test, Granger causality, Rescaled analysis, and principal statistical analysis, to find the cause of the catastrophic damages in 2020. The damage surrounding the Yongdam-dam in 2020 was confirmed to be caused by mis-management of the flood season water level. A similar pattern was found downstream of the Namgang- and Hapcheon-dams, however the damage caused via discharges from these dams in same year is uncertain. Conversely, a different pattern from that of the Yongdam-dam was seen in the areas downstream of Sumjingang- and Daecheongdams, in which the management of the flood season water level appeared appropriate and hence, the damages is assumed to have occurred via the increase in the absolute discharge amount from the dams and flood control capacity leakage of the downstream river. Because of the non-stationarity of the management data, we adapted the wavelet transform analysis to observe the behaviors of the dam management data in detail. Based on the results, an increasing trend in the discharge amount was observed from the dams after the year 2000, which may serve as a warning about similar trends in the future. Therefore, additional and continuous research on downstream safety against dam discharges is necessary.

• The Korean Journal of Financial Management
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• v.24 no.4
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• pp.107-134
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• 2007

This paper tests the relationship among returns, volatilities, contracts and open interests of KOSPI 200 futures markets with the various dynamic models such as granger-causality, impulse response, variance decomposition and ARMA(1, 1)-GJR-GARCH(1, 1)-M. The sample period is from July 7, 1998 to December 29, 2005. The main empirical results are as follows; First, both contract change and open interest change of KOSPI 200 futures market tend to lead the returns of that according to the results of granger-causality, impulse response and variance decomposition with VAR. These results are likely to support the KOSPI 200 futures market seems to be inefficient with rejecting the hypothesis 1. Second, we also find that the returns and volatilities of the KOSPI 200 futures market are effected by both contract change and open interest change of that due to the results of ARMA(1,1)-GJR-GARCH(1,1)-M. These results also reject the hypothesis 1 and 2 suggesting the evidences of inefficiency of the KOSPI 200 futures market. Third, the study shows the asymmetric information effects among the variables. In addition, we can find the feedback relationship between the contract change and open interest change of KOSPI 200 futures market.

• The Journal of Industrial Distribution & Business
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• v.9 no.5
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• pp.63-72
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• 2018

Purpose - This work analyzes, in detail, the specification of vector error correction model (VECM) and thus examines the relationships and impact among seven economic variables for USA - balance on current account (BCA), index of stock (STOCK), gross domestic product (GDP), housing price indices (HOUSING), a measure of the money supply that includes total currency as well as large time deposits, institutional money market funds, short-term repurchase agreements and other larger liquid assets (M3), real rate of interest (IR_REAL) and household credits (LOAN). In particular, we search for the main explanatory variables that have an effect on stock and real estate market, respectively and investigate the causal and dynamic associations between them. Research design, data, and methodology - We perform the time series vector error correction model to infer the dynamic relationships among seven variables above. This work employs the conventional augmented Dickey-Fuller (ADF) and Phillips-Perron (PP) unit root techniques to test for stationarity among seven variables under consideration, and Johansen cointegration test to specify the order or the number of cointegration relationship. Granger causality test is exploited to inspect for causal relationship and, at the same time, impulse response function and variance decomposition analysis are checked for both short-run and long-run association among the seven variables by EViews 9.0. The underlying model was analyzed by using 108 realizations from Q1 1990 to Q4 2016 for USA. Results - The results show that all the seven variables for USA have one unit root and they are cointegrated with at most five and three cointegrating equation for USA. The vector error correction model expresses a long-run relationship among variables. Both IR_REAL and M3 may influence real estate market, and GDP does stock market in USA. On the other hand, GDP, IR_REAL, M3, STOCK and LOAN may be considered as causal factors to affect real estate market. Conclusions - The findings indicate that both stock market and real estate market can be modelled as vector error correction specification for USA. In addition, we can detect causal relationships among variables and compare dynamic differences between countries in terms of stock market and real estate market.

• The Korean Journal of Health Service Management
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• v.10 no.3
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• pp.135-146
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• 2016

Objectives : This study explored ways to improve the quality of life related to oral health and the oral health of senior citizens by identifying the relevance of oral health-related quality of life issues, and satisfaction with dentures in elderly 65 years of age or older. Methods : This study surveyed 220 senior citizens who are currently using dentures and 65 years of age or older living in Busan. As a result, 200 questionnaires were returned. All of these questionnaires were used in the final analysis. The method of analysis was descriptive statistics using SPSS VER. 19.0, t-test, ANOVA, Pearson correlation coefficients, and regression analysis. Results : First, when verifying the difference in the quality of the health-related life of the oral cavity in accordance with the general characteristics, only average monthly income showed a significant difference. Second, the results of the analysis for factors that affect the quality of the health -related life of the oral cavity, fixation satisfaction, and mastication satisfaction, in that order, affected the general satisfaction of the elderly. Conclusions : Dentures satisfaction and the quality of the health-related life of the oral cavity show a high correlation and causality.

• Journal of Digital Convergence
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• v.13 no.10
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• pp.165-170
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• 2015

This study attempted to investigate an efficient human resources management plan by enhancing organizational performance and reducing the factors which influence turnover intention after analyzing the effects of job burnout on organizational effectiveness and turnover intention. To test a research model, after explaining the purpose of the study to them at work, data were obtained through a standardized questionnaire survey. To figure out the effects of job burnout on organizational effectiveness and turnover intention, causality was analyzed using the Structural Equation Model (SEM). According to hypothesis testing, a total of five hypotheses were chosen, and the following results were obtained: Job burnout had a significant effect on organizational commitment (-0.456), job satisfaction (-0.488) and turnover intention (0.501). In terms of relations between organizational effectiveness and turnover intention, organizational commitment (-0.350) and job satisfaction (-0.199) decreased turnover intention. Therefore, it is important to discover and analyze these obstacles which hinder employees from being absorbed in their work with attachment.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.15
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• pp.7-31
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• 2001

All legal systems set out the principle of full compensation of damages, which aims to fulfil the plaintiff's expectations by putting him into as good a position as he would have been in if the contract had been performed. On the other hand, they place some limitations on the full recoverability of damages for breach of contract. In Civil Law systems, 'fault' is a necessary requirement for liability for damages, and the extent of recoverable damages is directly related to the degree of the dependent's fault. This principle, however, is not adopted by Common Law systems, in which the dependent would be liable in damages for breach of contract even though the breach was not due to his fault. The CISG is in a similar position to the latter systems. In Common Law systems as well as CISG, the extent of liability of the party in breach for damages depends on whether he foresaw or could have foreseen the damages at the time of contracting. Unlike the position in Civil Law systems, foreseeability seems to be the most effective principle to decide the extent. The tests for remoteness centre on reasonable foreseeability or contemplation of the loss. The party in breach is liable even for loss indirectly caused to the other party provided that this loss was foreseeable or contemplated by the party in breach. However, this manner to decide remoteness may lead to unreasonable results in some cases. If the party in breach were the inveterate pessimist who foresaw all sorts of possible damages, he could foresee damages too remote from the breach of duty. If this fact were revealed in the course of trial, he should be liable for such indirect damages. This is really undesirable result. Therefore, as to the remoteness test, the criterion of whether the loss is foreseen or contemplated must not be adopted. Foreseeability by reasonable person must be the only available criterion.

• The Journal of Industrial Distribution & Business
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• v.10 no.9
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• pp.53-60
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• 2019

Purpose - The objective of this paper is to discover if there exists a relationship between the economic index and distribution industry index in Korean. Because of the distribution industry boom in the recent years, a lot of interest in the relationship between the economic index and distribution industry index in Korean and the economy has been generated. This article examine on the mutual influence between economic index and distribution industry index in Korean. Research design, data, and methodology - For this purpose, we use the vector-auto regression model, impulse response function and variance decomposition of the economic index and distribution industry index, Granger causality test using weekly data on the economic index and distribution industry price index in korea. The sample period is covering from January 2, 2010 to August 31, 2019. The VAR model can also be linked to cointegration analysis. Cointegration Analysis makes possible to find a mechanism causing x and y to move around a long-run equilibrium (Engle and Granger, 1987). This equilibrium means that external shocks may separate the series temporarily at any particular time, but there will be an overall tendency towards some type of long-run equilibrium. If variables are found to have this tendency they are said to be cointegrated and a long-run relationship between these series is established. These econometric tools have been applied widely into economics and business areas to analyze intertemporal linkages between different time series. Results - This research showed following main results. First, from the basic statistic analysis of the economic index and distribution industry index in Korean, the economic index and the distribution industry index in korea have unit roots. Second, there is at least one cointegration between the economic index and distribution industry index in Korean. Finally, the correlation between of the economic index and the distribution industry index in korea is (+) 0.528876. Conclusions - We find that the distribution industry price index Granger cause the economic index in korea. As a consequence, the distribution industry index affect the economic index in Korean. The distribution industry index to the economic index is stronger than that from the economic index to the distribution industry index.

• The Journal of the Korea Contents Association
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• v.6 no.8
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• pp.78-85
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• 2006

This study examined the stock return co-movement among Korean digital contents industry, American NASDAQ, and Japanese NIKKEI225. This is to identify the reaction of Korean digital contents industry on the movement of foreign stock market. To investigate the co-movements, during the period of 1999 to 2005, daily logarithm difference returns of each stock market indices are tested by the methodology of Granger(1963, 1969)'s causality test. The positive influence from NASDAQ index to Korean digital contents industry index are found, but not vice versa. It means that the market value of firms in Korean digital contents industry affected by the movement of American NASDAQ market which composite with digital IT firms. However, the co-movements with NIKKEI225 did not found.

• Journal of the Korea Convergence Society
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• v.11 no.1
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• pp.131-139
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• 2020

Gamers switch their games to a new when get bored or encounter more attractive ones. Switching cost varies by gamers and depends on how they are satisfied with their current game. This study evaluates the satisfaction with current games as the miltiple basic psychological need in the self-determination theory and suggests 'needs-costs' causality research model that explain the variety of gamer's switching behavior. As the empirical test to domestic mobile gamers, the autonomy fulfillment to current game affect reversely with those of autonomy and relatedness. Those relationships between need satisfaction and perceptual switching cost vary according to their age and game genre preference. The results would be applied to understand gamers' switching behavior.

• The Korean Journal of Financial Management
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• v.20 no.1
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• pp.125-162
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• 2003

This paper investigates the short- and long- run relationship among Korean, U.S. and Japanese construction indices. We conducted the Johansen's cointegration tests on the hypotheses that the construction indices of three countries we related in the long-run as well as in the short-run. The test results show that there exists no long-run relationship among three countrie's construction indices. In addition, the cointegrating relation did not exist for three countrie's stock market indices and five major Korean construction firms. It fumed out that the U.S. indices Granger-causes Japanese and Korean indices. This finding implies that there may exist international diversification benefit through forming a portfolio from these indices.