• 한국항공운항학회지
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• 제22권3호
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• pp.15-23
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• 2014

There have been CFIT(Controlled Flight Into Terrain) accidents that can be prevented if the crew executed go-around. This study is to analyse the common factors of three typical CFIT accidents of Korea in TEM(threat and error management) frame, and the examples of go-around gate and the countermeasures of eight airlines through the survey facilitating go-around to prevent CFIT. The common factors found in three typical CFIT accidents occurred in Korea or by Korean carriers turned out to be in mountainous terrain, in bad weather while in non-precision approach or circling approach by captain as PF(Pilot Flying) when crew make monitoring errors and communication errors. It also turned out that the crew in all three typical tragic CFIT accidents did not execute go-around in unstabilized approaches. The captains did not respond immediately when first officers advised them to go-around until it is too late. Seven out of eight Airlines answered that they use stabilized approach height as 1,000 feet to be stabilized earlier to have more safety margin by enhancing go-around gate regardless of the weather to prevent CFIT in the survey.

• 한국항공운항학회지
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• 제17권3호
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• pp.61-69
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• 2009

This research examined the influence of status and regulatory focus on go-around decision making. The result showed that there was no difference between captains and first offers on the go-around decision making about various landing situations. But there was significant relationships between regulatory focus and go-around decision making. Prevention focus was positively related with uncertain situation, and runway situation. Promotion focus has positive relationship with deficiency situation but has negartive relationship with runway situation.

• 한국항공운항학회지
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• 제29권1호
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• pp.1-8
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• 2021

Low level wind shear, which often occurs at Jeju International Airport, is a phenomenon that occurs when the topological location and topographical characteristics of Jeju Island are combined with weather characteristics. Low level wind shears, which are caused by rapid changes in wind direction and wind speed, pose a threat to aircraft safety and also cause abnormal situations, such as aircraft go-around, diversion, and cancellation. Many meteorological studies have been conducted on weather patterns, occurrence periods and frequency of low level wind shears. However, researches related to aircraft operations are limited where here we study the similarities and differences between strong southwest winds and bidirectional tailwind type low level wind shears based on aircraft go-around cases at Jeju International Airport. The results are expected to be used to enhance safety when operating to Jeju International Airport, which includes pilot training that reflects the characteristics generated by wind changes, pilot prior notification, providing pilots with latest trends, and increasing extra fuel.

• 대한수학회논문집
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• 제13권1호
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• pp.181-193
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• 1998

The Shannon sampling series is the prototype of an interpolating series or sampling series. Also the Shannon wavelet is one of the protypes of wavelets. But the coefficients of the Shannon sampling series are different function values at the point of discontinuity, we analyze the Gibbs phenomenon for the Shannon sampling series. We also find a way to go around this overshoot effect.

• Journal of Platform Technology
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• 제11권5호
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• pp.110-125
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• 2023

본 논문에서는 2019년 국내 공항을 기준으로 측정된 시계열 항공기 위치 데이터를 활용하여 국내 공항에 이착륙 시 접근 단계에서의 항공 위험상황 중 Go-Around 및 UOC_D 를 분석하고, 다양한 클러스터링 기반 머신 러닝 기법을 적용하여 국내 항공 데이터에서 가장 알맞은 분석 기법이 무엇인지를 실험을 통해 제시한다. 항공기 위치를 측정하기 위한 센서는 ADS-B를 단일로 사용하였으며, 클러스터링 기법들 중 K-Means, GMM, DBSCAN 등의 알고리즘을 사용하여 이상상황을 분류하기 위한 모델을 설계하였다. 그 중 해외에서는 RF 모델이 가장 나은 성능을 보였으나, 국내 항공 데이터에 대해서는 국내 지형에 특화된 부분을 반영한 GMM이 가장 높은 분류 성능을 보이는 것으로 실험을 통해 확인하였다.

• Transactions on Electrical and Electronic Materials
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• 제16권1호
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• pp.49-52
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• 2015

The change of the chemical structure of graphene oxide (GO) was investigated by periodical sampling of GO during exfoliation by using a sonicator. A significant amount of GO was exfoliated during up to 10 hr of sonication. Raman and Fourier transform infrared spectroscopy revealed a continuous increase of the G/D or C=C/C=O peak ratio of GO, as the sonication time increases. The photoluminescence (PL) intensity of each GO sample also decreased as a function of the sonication time. PL excitation spectra with three major peaks indicate that the sizes of $sp^2$ carbon clusters were enlarged by longer sonication. In addition, new excitation at around 300 nm proves the existence of newly developed small clusters of $sp^2$ carbons as the sonication time increased.

• 한국기계연구소 소보
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• 통권18호
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• pp.37-48
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• 1988

• 한국방재학회지
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• 제5권4호
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• pp.106-114
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• 2005

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 26-27 Oct. 1990
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• pp.704-709
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• 1990

This study presents the structure and the gate control algorithm of KAMOBOT (KAIST Mobile Robot). The mobile robot has a six-legged, cylindrical configuration, each leg of which is equiped with a wheel at the bottom. The robot can go up and down stairs, go over obstacles, move along curvilinear paths and rotate around it's geometric center. Such maneuverability can be achieved by using only three electric motors.

• 무역상무연구
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• 제27권
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• pp.69-95
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• 2005

East Asia has played an important role in the economic and social development in the Asian pacific region and in the global arena. In the region the impact of companies centralizing their logistics activities around a few distribution centers has already led some leading ports such as Singapore, Hong Kong to transform and expand their functions and business activities to provide port users with value added logistics services. Other ports in the region also have an important part to play in the total logistics Chain. In these environments, the maritime activities of Jang BoGo, who was the maritime king of the commercial maritime empire in East Asia in the 9th century, give many implications to the international logistics network strategy that Korea has to take in order to become a power of International Logistics. Though the trading and economic environments at that time may be quite different from today, the super-national maritime management pattern that Jang Bo-go, founder of the Northeast Asian maritime trading kingdom devised, gives us many implications in the global trading and economic environments, in the respects of overseas direct investment and international logistics. Accordingly, the paper aims to examine the establishment of hub port in Northeast Asia, modelled after the maritime network management strategy of Jang BoGo.