• Journal of KIISE:Software and Applications
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• v.30 no.10
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• pp.944-954
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• 2003

People are experiencing severe problems in temporal navigation as time-based contents and platforms become more popular Relatively limited research, however, has been conducted on temporal navigation compared to that on spatial navigation. This research aims to identify efficient temporal navigation aids for time-based contents. It proposes Time Navigator, a new temporal navigation system based on the episodic indexing theory, and evaluates its efficiency through two experiments with a computer-based simulator for digital TV The video contents of digital TV was focused on because it is one of the most representative time-based contents and platforms. Our results indicate that Time Navigator helps people navigate time -based contents more effectively. Its effects increase as the contents include more narratives.

• Journal of Navigation and Port Research
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• v.38 no.3
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• pp.227-232
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• 2014

There are three essential components of eLoran: dLoran, data map of ASF, and the Loran data channel. Particularly, dLoran improves navigation accuracy, which is the core technology of eLoran systems. The requirement of HEA's absolute accuracy, less than 20 meters, can be satisfied via dLoran measurements and their corrections. In this study, dLoran measurements using the Pohang Loran-C (9930M) station signal were conducted at Yeongil Bay. We established a dLoran reference station at Homigot Management Office for navigation aids within the Bay. We estimated the effectiveness of the dLoran between the reference site (Homigot Management Office) and a test site (Heunghwan beach) by measuring TOAs. We verified that the TOA data measured at these two regions were highly correlated. The temporal differences in the data between the dLoran reference station and test site were about 10~30 ns per day, which is equivalent to a ranging error of 3~9 m. This result shows that eLoran can meet the requirement of 8~20 meters position accuracy for maritime HEA by correcting the ASF at the user's receiver.