• Environmental and Resource Economics Review
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• v.22 no.4
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• pp.581-612
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• 2013

Opinet is the system that has announced the daily domestic petroleum price data from April 2008. This study's goal is to examine if the domestic petroleum(gasoline and diesel) prices adjust their prices asymmetrically comparing before-Opinet with after-Opinet. The results of this study found the evidence of asymmetric domestic petroleum prices before the Opinet and the evidence of symmetric domestic petroleum prices after the Opinet. Also the domestic petroleum prices after the Opinet adjust upward/downward nearly twice as fast when its actual value is below/above its equilibrium. According to this study, the domestic petroleum market works more efficiently than before.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.12
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• pp.1646-1653
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• 2020

In case that the train driving with diverse high-speeds is manipulates by real-time remote control in long-term evolution-railway (LTE-R) system with frequent handovers, the real-time safe transmission of train control messages is important element. The handover delay time stability method regardless of train speed in order to enhance the real-time remote train control stability in LTE-R system is proposed in the paper. Furthermore, the variable speeds and altitudes of train collected by real measurements are applied for upgrading simulation accuracy. The simulation results inform that not only there are stable and unstable ranges to A3 offset values, but the optimal offset value for average handover delay is in unstable range. However, the late handover with A3 offset values in stable range should be chosen to get the predictable handover delay regardless of train speed rather than the early handover with A3 offset values in unstable range, since the key value of high-speed Korea railway system is the stability.