• Korean Journal of Child Studies
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• v.36 no.4
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• pp.1-16
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• 2015

The purpose of this study was to examine the bidirectional relationship between the negative emotionality of 0-to 3-year-old and maternal parenting styles, focusing on warmth and reactivity. Four waves of panel data from the Korean Children Panel Study(KCPS) were analyzed in this study by means of autoregressive cross-lagged modeling. The results of this study were as follows. First, negative emotionality and maternal parenting styles were consistently stable for 0-to 3-year-old. Second, a bidirectional relationship between negative emotionality and maternal warmth parenting styles was confirmed according to the appearance of both parent and child effects. In other words, higher levels of negative emotionality was associated with lower maternal warmth parenting styles across time and in both directions. Additionally, the relationship between negative emotionality and maternal reactivity parenting styles were partially identified as being bidirectional in nature, whilst also being related to age. These findings suggested that parent education aimed at strengthening parenting skills, and programs designed to relieve negative emotionality of 0-to 3-year-olds are clearly needed.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.10 no.4
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• pp.253-258
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• 2010

The causal network represents the knowledge related to the dependency relationship between all attributes. If the causal network is available, the dependency relationship can be employed to estimate the missing values for improving the estimation performance. However, the previous method had a limitation in that it did not consider the bidirectional characteristic of the causal network. The proposed method considers the bidirectional characteristic by applying prior and posterior conditions, so that it outperforms the previous method.

• Proceedings of KOSOMES biannual meeting
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• 2006.11a
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• pp.181-186
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• 2006

Geostationary Orbit satellite, unlike other sun-synchronous polar-orbit satellites, will be able to take a picture of a large region several times a day (almost with everyone hour interval). For geostationary satellite, the target region is fixed though the location of sun is changed always. However, Sun-synchronous polar-orbit satellites able to take a picture of target region same time a everyday. Thus Ocean signal is almost same. Accordingly, the ocean signal of a given target point is largely dependent on time. In other words, the ocean signal detected by geostationary satellite sensor must translate to the signal of target when both sun and satellite are located in nadir, using another correction model. This correction is performed with a standardization of signal throughout relative geometric relationship among satellite-sun-target points. This relative ratio called bidirectional factor. To find relationship between time and $[L_w]_N$/Bidirectional Factor differences, we are calculate solar position, geometry parameters. And reflectance, total radiance at the top of atmosphere(). And water leaving radiance, normalized water leaving radiance. And calculate bidirectional factor, that is the ratio of $[L_w]_N$ between target region and aiming the point. Then, we can make the bidirectional factor lookup table for one year imaging. So, we suggested for necessary to simulation experiment bidirectional factor in more various condition(wavelength and ocean/air condition).

• Journal of applied mathematics & informatics
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• v.9 no.1
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• pp.349-357
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• 2002

In this paper, we analyze queueing behaviors and investigate the possibilities of reducing and controlling shortages and oversupplies in the bidirectional queueing system which forms a negative queue by demand and a positive queue by supply. Interarrival times of units in the bidirectional queueing system investigated are exponetially distributed. Instant pairing off implies that queue can be either positive or negative, but not both at the same time. The results include a proof that sum of queue lengths is minimized if rates of demand and supply in each system are equal and optimum solutions for rates of supply which minimize the sum of queue lengths when rates of demand and sum of rates of supply are given. In addition, the relationship between the ordinary queueing system and the bidirectional queueing system is investigated.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.5
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• pp.410-415
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• 2013

This paper proposes a bidirectional platoon control law using a coupled distance error based on the backstepping-like feedback linearization control method for an interconnected mobile agent system with a string structure. Unlike the previous results where the single agent was controlled using the only own information without other agents, the proposed control law cannot show the only distance error convergence of each agent, but also the string stability of the whole system. Also, the control performances are improved by the proposed control law in spite of low performance of bidirectional control strategy in the previous results. The proposed bidirectional platoon control algorithm is based on the backstepping-like feedback linearization control method. The position errors between each agent and the preceding and the behind agents are coupled by weighted summation. By the proposed control law, the distance error of each agent can converge to zero while the string stability is guaranteed when the coupled errors can converge to zero. To this end, the back-stepping control method is employed. The pseudo velocity input is determined considering the kinematic relationship between agents and the string stability. Then, the actual dynamic control input is determined to make the actual velocity converge to the pseudo velocity input. The stability analysis and the simulation results of the proposed method are included in order to demonstrate the practical application of the proposed algorithm.

• Proceedings of the KSRS Conference
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• v.1
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• pp.79-81
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• 2006

Geostationary ocean satellite, unlike other sun-synchronous polar-orbit satellites, will be able to take a picture of a large region several times a day (almost with every one hour interval). For geostationary satellite, the target region is fixed though the location of sun is changed always. Thus, the ocean signal of a given target point is largely dependent on time. In other words, the ocean signal detected by geostationary satellite sensor must translate to the signal of target when both sun and satellite are located in nadir, using another correction model. This correction is performed with a standardization of signal throughout relative geometric relationship among satellite - sun - target points. One signal value of a selected pixel point of the target region of Geostationary Ocean Colour Imager (GOCI) would be set up as a standard, and the ratio of all remained pixel point can be calculated. This relative ratio called bidirectional factor, the result of modelling of spatiotemporal variation of bidirectional factor is shown.

• The Journal of Asian Finance, Economics and Business
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• v.4 no.1
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• pp.25-38
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• 2017

This study investigates the causal relationship between stock prices and exchange rates for six Middle Eastern countries, namely, Egypt, Iran, Jordan, Kuwait, Oman, and Saudi Arabia before and during (after) the 2007 global financial crisis for the period between January 2004 and September 2015. The sample is divided into two sub-periods, that is, the period from January 1, 2004 to September 30, 2007 and the period from October 1, 2007 to September 30, 2015, to represent the pre-crisis period and the post-crisis period, respectively. Using Vector Autoregressive (VAR) model in a multivariate framework (including two control variables, inflation rates and oil prices) the results suggest that in the case of Jordan, Kuwait and Saudi Arabia, there exists bidirectional causalities after the crisis period but not the before. The opposite status is available for the case of Iran. In the case of Oman, there is bidirectional causality between the variables of interest in both periods. The results also reveal that the relationship between stock prices and exchange rates has become stronger after the 2007 global financial crisis. Overall, the results of this study indicate that fluctuations in foreign exchange markets can significantly affect stock markets in the Middle East.

• The Journal of the Convergence on Culture Technology
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• v.9 no.3
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• pp.281-286
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• 2023

This study analyzed the causal relationship between housing sales prices and jeonse prices in Seoul, specifically in the Gangnam and Gangbuk neighborhoods. The time-invariant Granger causality test showed bidirectional causality between the sales price and the jeonse price in Seoul and Gangbuk, but no bidirectional causality was found in Gangnam. However, the time-varying Granger causality test showed a Granger causal relationship between the housing jeonse price and the sales price for the entire period after 1993 in all three areas. Notably, the causal effect of jeonse prices on sales prices has been continuous in Gangnam since 2010. These analysis results suggest that an increase in liquidity supply to the jeonse market could increase volatility throughout the housing market, given the strong influence between the sales and jeonse markets in both directions.

• Journal of the Korean Home Economics Association
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• v.38 no.5
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• pp.15-24
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• 2000

The purpose of the study was to explore the causal relationships between delinquency and self-esteem among adolescents. The subjects of this study were 497 adolescents attending middle schools in Pusan. The data was collected by longitudinal research design of 9 month interval In first, second wave, the participants completed the delinquency scale and the multidimensional self-esteem inventory that includes home self, peer-related self, teacher-related self, academic-general serif, physical appearance self, physical competence self, and personality self, respectively The major findings of this study were as follows: these causal relationships differed among subdimensions of self-esteem, 1)the causal relationship between delinquency and home self was bidirectional, 2)the causal relationship between delinquency and peer-related self, teacher-related self, academic-general self, and personality self was unidirectional, 3)the causal relationship between delinquency and physical appearance self, physical competence self was not statistically significant.

• Proceedings of the Korea Technology Innovation Society Conference
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• 2004.05a
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• pp.77-97
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• 2004

In this paper we: (1) analyze the relationship among public R&D investment, private R&D investment, and GDP by employing the Granger causality test; (2) examine if there is any country-specific pattern in the relationship by testing the cases of Korea, the U.S. and Japan. We found some common results for the above countries as follows: (i) GDP causes Public R&D, not vice versa; (ii) Private R&D causes GDP; and (iii) Public R&D does not cause Private R&D. For the bivariate model of GDP and total R&D, the results show the existence of one-way causality running from total R&D to GDP for both U.S, and Japan. We also found bidirectional causal relationship between GDP and total R&D for Korea, which could be interpreted as a typical pattern for newly industrialized countries.