• Atmosphere
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• v.18 no.1
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• pp.43-53
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• 2008

A new proposition on the definition of the tropical cyclone (TC) which influences the Korean Peninsula (KP) is presented. The definition is based upon the TC track and intensity, 34 wind swath considering the TC size, and the line of 200 nautical mile (NM) from the KP shore which is the boundary of the official warning of Korea Meteorological Administration. Four types are proposed. First type is TC that hits the KP inland. Second is TC that falls within the 200-NM boundary. Third type is TC that passes outside the 200-NM boundary but large enough to significantly influence the KP. Last, the cases for a TC which are downgraded to the midlatitude cyclone and hit the KP are included. 30-year reanalysis reveals that 21 tropical cyclones should be included in the TC list that influenced the KP during the period from 1977 to 2006, which corresponds to 3.93 TCs per year. Among them, number of type I, II, III and IV TCs turn are to be 36, 47, 10, and 16, respectively. The net increase found in the current reanalysis is 2, 5, 7, and 7 for each type.

• Journal of Advanced Navigation Technology
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• v.25 no.3
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• pp.248-255
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• 2021

The main causes of the July 2013 OZ 214 accident were poorly performed approach and the failure to recognize the autothrottle in the HOLD position which the automated speed control was not provided. The pilots late decision for go-around was also a critical factor leading to the accident. The B777 POM restricts the use of FLCH mode beyond the FAF. This research utilized the QAR data of an airline's B777 fleet in the period of two years where 44 cases were found. In many cases, the FLCH mode was used for rapid descent from an higher than normal situation. In addition, in the base turn, continuous use of FLCH mode even when the path was below the glide path were observed. Airports with elevation above 500 ft MSL had a higher rate of occurrence. In this research, the proper descent planning and vertical path monitoring, and the adherence to the limitation set in the manuals and the stabilized approach criteria were re-emphasized as mitigation to reduce event occurences.