• 한국정보시스템학회지:정보시스템연구
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• 제31권3호
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• pp.177-195
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• 2022

Purpose This paper aims to prepare a full operational readiness by establishing an optimal flight plan considering the weather conditions in order to effectively perform the mission and operation of military aircraft. This paper suggests a flight prediction model and rules by analyzing the correlation between flight implementation and cancellation according to weather conditions by using big data collected from historical flight information of military aircraft supplied by Korean manufacturers and meteorological information from the Korea Meteorological Administration. In addition, by deriving flight rules according to weather information, it was possible to discover an efficient flight schedule establishment method in consideration of weather information. Design/methodology/approach This study is an analytic study using data mining techniques based on flight historical data of 44,558 flights of military aircraft accumulated by the Republic of Korea Air Force for a total of 36 months from January 2013 to December 2015 and meteorological information provided by the Korea Meteorological Administration. Four steps were taken to develop optimal flight prediction models and to derive rules for flight implementation and cancellation. First, a total of 10 independent variables and one dependent variable were used to develop the optimal model for flight implementation according to weather condition. Second, optimal flight prediction models were derived using algorithms such as logistics regression, Adaboost, KNN, Random forest and LightGBM, which are data mining techniques. Third, we collected the opinions of military aircraft pilots who have more than 25 years experience and evaluated importance level about independent variables using Python heatmap to develop flight implementation and cancellation rules according to weather conditions. Finally, the decision tree model was constructed, and the flight rules were derived to see how the weather conditions at each airport affect the implementation and cancellation of the flight. Findings Based on historical flight information of military aircraft and weather information of flight zone. We developed flight prediction model using data mining techniques. As a result of optimal flight prediction model development for each airbase, it was confirmed that the LightGBM algorithm had the best prediction rate in terms of recall rate. Each flight rules were checked according to the weather condition, and it was confirmed that precipitation, humidity, and the total cloud had a significant effect on flight cancellation. Whereas, the effect of visibility was found to be relatively insignificant. When a flight schedule was established, the rules will provide some insight to decide flight training more systematically and effectively.

• 한국항공운항학회지
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• 제19권1호
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• pp.29-37
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• 2011

Last April, Europe was severly damaged as all social and economic activities came to a halt prompted by the cancellation of all flights resulting from volcanic ash. This exemplifies that the meteorology conditions have significant influence on the flights of airplanes. Hence, in this research the influence that the meteorology has on the domestic flights and its characteristics will be examined, and the core meteorological factors that influence flights in each airport will be drawn. In order to do this, statistical analysis on the influence that the meteorology has on flights was carried out in order to analyze the data about flight cancelation and delay and also its cause, primarily based on the Gimpo, Gimhae, and the Jeju airports. As a result, first, the meteorological factors which impact flight cancellation and delay were different among the domestic airports, and second, it was analyzed that fog was the main meteorological factor in the Gimpo airport, strong wind in the Jeju airport, and fog in the Gimhae airport. Third, between the day the flights were cancelled and delayed occurred, and the day that weren't, the fact that there existed a difference among the actual meteorological factors was statistically drawn. With the result of such analysis, meteorological factors pertaining to the cancellation and delay of flights must be considered seperately by each airport and specialized meteorological information must be provided accordingly. Further, when selecting the position of an airport that is to be constructed in the future, implications that there is a definite need for the meteorology effect evaluation based on past meteorology data can be drawn.

• 한국생활과학회지
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• 제24권1호
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• pp.49-67
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• 2015

The study aims to review airline services like the domestic line performance, the general flight fares and website discount fairs, reservation cancellation and cancellation charges, reroutings and personal discount system of the low cost carriers(LCC), and suggest what needs to be done to improve the airline service. The improvements to be made by the LCC should include increasing regular domestic lines, providing information compared for consumers, relieving the toll to call the service center, revising the conditions on reservation cancellation penalty, rerouting charges, revising the consumer dispute resolution standards, and promoting frequent fliers program. Development strategies should be established that can boost consumer benefits through the improvement of the airline services.

• 한국항공운항학회지
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• 제25권1호
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• pp.1-10
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• 2017

A heavy foggy event accompanying with complex coastal fog was investigated in this study. This heavy foggy event occurred on FEB 11, 2015. Due to reduced visibility with this foggy event induced more than 100times serial traffic accidents over the Young-jong highway, and Flights from 04:30 AM to 10:00 AM were cancelled on Inchon International Airport. This heavy foggy event was occurred in synoptic and mesoscale environments but dense coastal fog were combined with a combination of sea fog, steam fog, and radiation fog. This kind of coastal fog can predicted by accurate analysis of the direction of the air flow, sea surface temperature(SST), and 925hPa isotherms from numerical weather prediction charts and real time analysis charts.

• 항공우주정책ㆍ법학회지
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• 제35권2호
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• pp.197-224
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• 2020

본 논문에서는 2020년 3월 12일 제시된 EU사법재판소의 A and Others v. Finnair Oyj 판결을 검토해 보았다. 본 판결은 대체항공편에서의 운항지연의 경우에도 금전보상청구를 인정하였다는 점에서 중요한 의미가 있는 판결이다. 이에 본 논문에서는 아직 아직 국내에 소개되지 않은 본 판결을 분석하여, 향후 항공여객의 권리보호 논의 내지는 EC 261/2004 규칙의 해석론적 검토와 관련한 비교법적 참고자료의 역할을 하고자 하였다. 본 논문에서는 먼저 A & Others 판결의 사실관계를 정리하고 EU사법재판소의 판시사항을 개관해 보았다. 몇 가지의 논점들과 EU사법재판소의 판단 법리를 정리한 후, 논문의 구성적 논점을 크게 ① 대체항공편의 운항지연과 그와 관련한 여객의 보상원칙 및 ② 운송인 면책사유로서의 특별한 사정의 해석기준으로 나누었다. 이렇게 논점을 구분하여, EC No 261/2004 규칙의 각 규정들, 기존에 제시된 EU사법재판소 판례의 경향과 함께 본 A & Others 판결을 구체적으로 살펴보았다. 결론적으로는 본 판결의 취지와 항공여객운송실무상의 시사점 등도 생각해보았다. 또한 우리법과의 비교법적 논의도 간략하게나마 언급해 보았다.

• 한국항공운항학회지
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• 제15권2호
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• pp.40-47
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• 2007

Poor visibility is very important information in aviation meteorology factor, because secure safety, trust and economical efficiency increase for aircraft movements. The Incheon International Airport 4 years recent times was to period aircraft movements delay and cancellation due to meteorology is 52% and 30%. And then fog is 63% and 43% in meteorology factor. Therefore, the analysis against the economic loss size of an airline due to the fog is necessary. This study is indirectly estimated economic disaster scale of flight return and cancellation due to the fog in the Incheon International Airport from 5 to 6 March 2006. This is based on an aviation operational statistics data and meteorology observation data. Result of estimated, total 14 flights return to Gimpo, Jeju and Gimhae in this period are about 208,205,700 won. And estimated total 10 flights cancellation are about 718,657,000 won.

• 전기학회논문지
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• 제66권7호
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• pp.1078-1082
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• 2017

This paper presents an L1 optimization based filtering technique which effectively eliminates the optical misalignment effects encountered in the squint guidance mode with strapdown seekers. We formulated a series of L1 optimization problems in order to separate the bias and the gradient components from the measured data, and solved them via the alternating direction method of multipliers (ADMM) and sparse matrix decomposition techniques. The proposed technique was able to rapidly detect arbitrary discontinuities and gradient changes from the measured signals, and was shown to effectively cancel the undesirable effects coming from the seeker misalignment angles. The technique was implemented on embedded flight computers and the real-time operational performance was verified via the hardware-in-the-loop simulation (HILS) tests in parallel with the automatic target recognition algorithms and the intra-red synthetic target images.

• 항공우주정책ㆍ법학회지
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• 제31권2호
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• pp.37-72
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• 2016

항공우주분야에서 특수 목적 항공기 이외에도 시제기, 무인비행장치, 우주발사체 등 다양한 형태의 제작물공급계약이 증가하고 있다. 도급인의 입장에서는 거액의 비용을 지출하여 제작물을 공급받기로 예정되어 있었는데, 제품의 품질과 성능의 기준을 제시하는 구매규격서가 부실하거나 성능미달여부를 판단할 만한 능력이 부족한 경우에는 목적 달성 불능 이외에도 막대한 시간과 비용을 소모하게 된다. 수급인으로서도 계약 목적 달성에 필요한 성능과 품질을 갖춘 제작물을 공급할 능력이 없음에도 불구하고 무리하게 계약을 체결하게 되면, 일의 미완성에 따른 매몰비용과 계약해제에 따른 손해배상을 감수하여야 하므로 막대한 손해가 발생한다. 대상사안에서 피고는 원고에게 구매규격서에 규정된 바와 같이 ILS Offset 비행이 가능한 Happy Box 방식에 의한 항공기를 납품하도록 하였으나, 원고는 RNAV 방식에 의한 항공기를 납품하려고 하였다. RNAV 방식에 의하여도 ILS 지상신호의 검사가 가능하더라도 원고가 주장하는 방식으로 제작된 항공기는 구매규격서에서 요구한 ILS Offset 비행기능을 갖추지 못하여 피고가 구매규격서에서 요구한 목적을 달성할 수 없으므로, 이를 이유로 한 피고의 계약해제가 적법한지 여부가 문제되었다. 이 사건 계약의 목적물인 항공기는 부대체물에 해당하므로 이 사건 계약은 도급의 성질을 가지고, 따라서 이 사건 계약에서 일이 완성되었다고 하려면 항공기의 주요구조 부분이 약정된 대로 제작되어 사회통념상 일반적으로 요구되는 성능을 갖추고 있어야 한다. 그런데 원고가 납품한 항공기는 구매규격서에서 요구한 ILS Offset 비행기능을 갖추지 못하여 피고가 구매규격서에서 요구한 목적을 달성할 수 없으므로 중대한 하자가 있고, 이러한 하자는 원고가 보수하는 것이 불가능하므로, 이를 이유로 한 피고의 계약해제는 적법하다.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1989년도 춘계학술대회
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• pp.27-28
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• 1989

In conventional line scan angiography, flow signal has been enhanced by the time_of_flight effect while the signal from stationary tissues has been suppressed by the saturation rf pulse followed by spoiling gradients. Due to the inhomogeneous rf field and the tissue dependent T1 relaxation time, however, stationary tissues can not be suppressed completely or uniformly, and the remnant stationary signal deteriorates the resultant angiogram. Here, the complete cancellation of stationary tissues is made possible by the spectral analysis of a series of repetitive line images of the same slice. The Fourier transformation of a set of line images results in the spectrum images, where stationary tissues are collected into the dc component while arteries are included in harmonic components because of the variation of the flow velocity and the resultant flow signal in arteries according to the cardiac cycle. The summation of harmonic components excluding the dc component results in the angiogram of arteries with the complete cancellation of stationary tissues.

• 항공우주정책ㆍ법학회지
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• 제30권2호
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• pp.249-277
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• 2015

유럽연합이 제정하여 시행하고 있는 Regulation (EC) No 261/2004 ("Regulation")는 비자발적 탑승거부, 운항취소, 운항지연 등의 사안에 대해 항공승객을 보호하는데 주목적을 두고 있다. 이와 관련하여 항공편 지연으로 불편을 겪은 승객들이 탑승거부, 운항취소에 대해 명시적으로 적용되는 제7조에 따른 금전 보상청구권을 청구한 사건들이 있었다. 이에 대해 유럽연합 사법법원(Court of Justice of the European Union, CJEU)은 승객들에게 시간적인 손실이 발생한다는 점에서 항공편이 운항취소된 경우와 운항지연된 경우는 동일하므로, 당초 항공사가 설정한 총 비행시간 보다 3시간이 초과되어 운항이 지연된 경우에는 해당 승객이 자발적 탑승거부나 운항취소와 마찬가지로 금전손실 보상청구권을 행사할 수 있다고 판단하였다. Regulation상에 운항지연의 경우 제7조의 보상청구권이 적용된다는 명시규정이 존재하지 않음에도 불구하고, 승객의 보호라는 Regulation의 입법취지를 고려하여 법원이 적극적으로 그러한 권리를 긍정한 것이다. 이러한 법원의 관점은 규정의 유추해석이라는 비판을 받을 가능성도 있지만, Regulation에 산재되어 있는 운항취소와 운항지연에 관한 일괄적 취급에 관한 근거 및 승객보호라는 Regulation의 입법취지를 고려할 때 설득력을 가진다. 더욱이 법원은 운항지연의 경우 Regulation과 몬트리올 협약이 동일한 내용을 규정하고 있지 않으므로 몬트리올 협약 제29조는 이 경우에 적용되지 않고 양자는 충돌되지 않는다고 보고 있다. 즉, Regulation은 항공편의 지연이라는 사실에 관한 승객의 불편과 손실을 보호하는 규범인 반면, 몬트리올 협약은 지연이라는 사실로 인하여 인과관계가 인정되는 범위에서 발생된 손해에 관한 배상을 규정하고 있다는 것이다. 위와 같은 유럽연합의 규정과 법원의 견해는 승객보호에 관한 진보적인 성향을 잘 보여주는 선구적인 내용이라고 할 수 있다. 구체적인 규정 없이 승객보호를 위한 절차와 계획의 수립의무만을 선언적으로 규정하고 있는 현재의 우리나라 항공법이 참고할 필요가 있을 것으로 본다.