• Journal of Korean Society of Transportation
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• v.23 no.4 s.82
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• pp.7-16
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• 2005

Rejected Takeoff Accidents are not common. but if occurred, it leads to big disaster From the year of 1959, when Jet Transport service opened, to the year of 2000, Rejected Takeoff accidents/incidents occurred total of 94 cases. All cases led to overrun, and major cause is to initiate stopping maneuvers over $V_1$, takeoff decision speed, according to National Transport Safety Board of America. Similar results are represented in Aviation Safety Reporting System of National Aeronautics and Space Administration. So I believe that it is worth studying if Airplane Flight Manual, which is the reference Performance criteria, is appropriate to operations of line pilots. The definition of $V_1$ has been revised a couple of times and Rejected Takeoff Certification Standards for Transport Airplanes was changed in 1998. It shows that up to now there are some portions unreasonable. This study focused on gathering the pilot's tendency for current Rejected Takeoff Procedures of K airlines and analyze the factors they concern. I chose B777 airplane and actually measured the recognition and reaction time of the rejected takeoff transitions through Simulators. And compared the results with the data of flight test and Airplane Flight Manual.

• Journal of Advanced Navigation Technology
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• v.12 no.6
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• pp.559-566
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• 2008

In this paper, we propose a voice instruction-based takeoff system for aircraft including unmanned aerial vehicle (UAV). The system consists of voice recognition (VR), flight state checking and instruction (command) execution. Employing VR technology, the proposed takeoff system can provide simplified and more reliable takeoff procedures to pilots. By virtue of the VR-based system it is expected that human errors during takeoff phase can be reduced and further navigation safety can be improved.

• Korean journal of applied entomology
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• v.40 no.2
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• pp.125-129
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• 2001

Some wingless species have evolved take-off behaviors that enable them to become airborne. We examined aerodynamic attributes of dispersal relative to the body size and standing vs. walking postures for three phytoseiids that were suspected to have different take-off behaviors and dispersal abilities, Phytoseiulus persimilis Athias-Henriot, Neoseiulus fallacis (Carman) and N. californicus (McGregor). The average vertical profile of Pp in the walking position was significantly higher than those of Nf and Nc when in walking position. The body height of Nf in the standing posture was significantly greater than the body height of Pp when in the walking position. Cross-section areas also showed similar patterns of difference. Nf in the standing posture would have more than twice the drag force than in walking posture because of more fluid momentum in the wind boundary layer However, Pp in the walking position would have similar drag to Nf in the standing posture because of a higher vertical profile and larger size. Thus we add the scientific evidence of presence and absence of take-off behavior of some phytoseiid mites and evolutionary aspects of aerial dispersal are further discussed.

• Journal of Advanced Navigation Technology
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• v.27 no.5
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• pp.658-665
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• 2023

Take-off weight is a key factor for improving accuracy when estimating an aircraft's carbon emissions and fuel consumption. However, the takeoff weight contains sensitive payload information that can infer the airline's management strategy, making it impossible to leak it outside. Although several models for estimating takeoff weight have been presented in previous studies, the researcher points out that there are limitations of the study caused by variables at the pilot's discretion. In this paper, several variables related to takeoff weight are identified to suggest a way to control these limits. Among them, variables that can improve the accuracy of takeoff weight are selected and an estimation equation is presented by applying them to ADS-B information. The proposed estimation does not estimate the average takeoff weight but has the advantage of being able to estimate all ranges of the takeoff weight.

• The Journal of Aerospace Industry
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• s.66
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• pp.17-44
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• 2003

항공기의 이륙단념(Rejected Takeoff) 사고는 흔히 발생하지는 않지만, 발생하면 큰 사고로 이어지는 경우가 대부분이다. 제트기에 의한 운송서비스가 본격적으로 시작된 1959년부터 2000년 까지의 이륙단념 사고사례를 조사해 본 결과 총 94건이 발생했다. 사고사례 모두가 활주로 이탈로 이어졌고, 그 주요 원인은 이륙결심 속도를 넘어서 조작을 시작했기 때문이라고 미국교통안전위원회(NTSB)에서 발표하였다. 이런 결과는 미국 항공우주국(NASA)의 준사고보고제도(ASRS)에서 조사한 자료에도 비슷한 결과가 나온 바 있다. 따라서 항공기 운항의 기준이 되는 항공기 비행규정(Airplane Flight Manual)을 만들 때 적용하는 미국연방항공법(FAR)상의 이륙단념 전환시간이 국내 현장조종사에서도 적합한 지에 관해 연구하였다.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.4 no.1
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• pp.25-38
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• 1996

본 연구에서는 항공기 사고의 70%이상을 차지하는 이 ${\cdot}$ 착륙단계 중에서, 이륙 직후 저고도에서 동력이 상실되었을 경우에 이륙활주로 방향으로 Turning Back하는 것은 어떠한 안전 한계를 지니고 있는지를 알아보기 위하여, 우선 조종사에 대한 설문 조사를 실시하여 비행 경력별로 이륙 직후 동력 상실시의 비상 처치 경향과 위험에 처할 확률을 조사하였다. 그리고 실제 활공 성능이 우수한 M20J 항공기와 기동 성능이 우수한 FH20 항공기를 이용한 비행 시험을 통하여 이륙 직후 Turning Back to Runway조작 시의 고도 손실과 선회시 하강율을 실험 자료로 구하였다. 비행 시험 자료를 비교 적용함은 물론 선회 소요 시간과 고도 손실, 선회율과 활공 속도와의 관계 등의 항공 역학적 이론을 적용한 분석 근거에 기초하여 안전하게 Turning Back to Runway 조작을 시작할 수 있는 안전 고도 한계 및 선회율을 제시하였다.

• Asia Marketing Journal
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• v.10 no.2
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• pp.1-29
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• 2008

The objective of our study is to provide an exploratory model for forecasting sales take-off timing of a product in the context of multi-national markets. We evaluated the usefulness of key predictors such as multiple market information, product attributes, price, and sales for the forecasting of sales take-off timing by applying the suggested model to monthly sales data for PDP and LCD TV provided by a Korean electronics manufacturer. We have found some important results for global companies from the empirical analysis. Firstly, innovation coefficients obtained from sales data of a particular product in other markets can provide the most useful information on sales take-off timing of the product in a target market. However, imitation coefficients obtained from the sales data of a particular product in the target market and other markets are not useful for sales take-off timing of the product in the target market. Secondly, price and product attributes significantly influence on take-off timing. It is noteworthy that the ratio of the price of the target product to the average price of the market is more important than the price ofthe target product itself. Lastly, the cumulative sales of the product are still useful for the prediction of sales take-off timing. Our model outperformed the average model in terms of hit-rate.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.10 no.1
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• pp.83-93
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• 2002

• Aerospace Industry
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• v.85
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• pp.41-43
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• 2004

아무 계획도 짜지 않은 것은 실패할 계획을 짜는 것이나 마찬가지다. 항공기가 이륙하여, 비행중에 있을지도 모르는 여러가지 돌발상황에도 불구하고 추락하지 않고 목적지까지 안전하게 도착하기 위해서는 세심한 정성으로 비행계획을 짜고 비상시에는 탁월한 순발력으로 대처해야 할 것이다. 그러한 능력과 마음가짐을 갖추고 항공기의 이륙부터 비행, 착륙까지의 전 과정을 꼼꼼히 계획하고 보살피는 사람들 - 운항관리사가 이번 기사의 주제이다.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.2
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• pp.183-190
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• 1994

본 연구에서는 항공기 사고의 대부분을 차지하는 이${\cdot}$착륙단계중에서, 이륙직 후 저고도에서 동력이 상실되었을 경우에 이륙활주로 방향으로 Turning Back하는 것은, 어떠한 안전 한계를 지니고 있는지를 선회 소요시간과 고도손실, 선회율과 활공속도와의 관계 등의 이론적인 근거에 기초하여 분석하고자 한다.