• Journal of Astronomy and Space Sciences
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• 제27권4호
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• pp.407-412
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• 2010

Software reusability is one of key factors which impacts cost and schedule on a software development project. It is very crucial also in satellite simulator development since there are many commercial simulator models related to satellite and dynamics. If these models can be used in another simulator platform, great deal of confidence and cost/schedule reduction would be achieved. Simulation model portability (SMP) is maintained by European Space Agency and many models compatible with SMP/simulation model interface (SMI) are available. Korea Aerospace Research Institute (KARI) is developing hardware abstraction layer (HAL) supported satellite simulator to verify on-board software of satellite. From above reasons, KARI wants to port these SMI compatible models to the HAL supported satellite simulator. To port these SMI compatible models to the HAL supported satellite simulator, simulation scheduler is preliminary designed according to the SMI standard.

• 한국항공우주학회지
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• 제34권7호
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• pp.105-111
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• 2006

항공기 엔진은 항공기가 각종 기동을 수행하도록 추력을 발생하는 것 외에 기동 수행을 위해 작동되는 조종면에 공급될 유압계통의 동력과 각종 항전장비 작동을 위한 전기계통의 동력을 공급한다. 엔진으로부터 제공되는 동력은 엔진의 고압압축기로부터 추출되기 때문에 축마력(Horsepower Extraction, HPX)이라하며, 추출되어 제공되는 엔진 축마력이 유압계통과 전기계통에서 요구하는 요구 축마력보다 작게 되면 엔진에 과도한 부하가 걸려 엔진회전수 감소(Rollback) 및 심한 경우 실속(stall)등이 발생할 수 있다. T/A-50체계개발 동안 요구 축마력과 엔진의 공급 축마력에 대한 비교 해석을 수행하였고, 해석 결과 엔진 축마력이 요구 축마력보다 작은 것을 확인하였다. 엔진 축마력 증가를 위한 엔진 제어 스케쥴 변경이 수행되었으며, 변경된 제어 스케쥴이 장착된 엔진을 이용하여 T/A-50비행시험을 수행하였다. 비행시험 결과를 통해 해석 결과 및 변경된 제어 스케쥴의 타당성을 검증하였다.

• 대한산업공학회지
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• 제11권2호
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• pp.155-163
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• 1985

This paper presents a heuristic algorithm for a multidepot aircraft scheduling and crew scheduling with deal-head flights. This algorithm is extended from a Greedy heuristic algorithm for a multi-depot multi-salesman traveling salesman problem. We first transform a given flight schedule into a multi-depot multi-traveling salesman problem, considering aircraft flight policies and crew management constraints. Then we solve this problem by applying a modified Greedy heuristic algorithm.

• 한국항공우주학회지
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• 제41권9호
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• pp.681-688
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• 2013

불가피하게 급증하는 항공기 수요량에 따른 여러 가지 문제들을 해결하는 방안으로 항공기의 지연시간을 줄여, 공항의 수용력을 극대화하는 항공교통관리가 주목받고 있다. 본 논문은 공항주변 항공교통흐름을 원활히 하여 항공기 처리량을 최대화하는 항공기 스케줄링의 최적화를 목적으로 한다. 본 연구에서 개발한 스케줄링 기법은 스케줄링 문제를 수학적으로 모델링한 후, 혼합정수선형계획법과 유전자 알고리즘을 도입하여 항공기 지연시간을 최소로 하는 최적의 스케줄링을 제공한다. 최적화된 스케줄링과 실제 인천 공항에서의 항공기 스케줄링과 비교해 보았고, 그 결과 최적화된 스케줄링이 제공하는 항공기 처리량이 현재 인천 공항에서 처리하는 항공기보다 현저히 높다는 결과를 확인할 수 있었다. 본 연구에서 개발한 스케줄러는 향후 항공기의 포화 상태를 적절하게 대처하는데 큰 도움을 줄 것이라 예상되어진다.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2007년도 추계학술대회 및 정기총회
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• pp.27-37
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• 2007

Many problems related to airline business belong to large-scale optimization problems, so that it is expected that the state-of-art optimization techniques are widely applied to making the airline operation effective and competitive. This paper introduces the concepts and mathematical models of various optimization problems in airline system. Airlines involve many activities that utilize airline resources such as aircrafts and crews to make profit. We view the airline activities in the planning and operational aspects. In the planning viewpoint, we discuss the flight schedule design problem that impacts on passenger demand directly. For aircraft and crews, we deal with fleet assignment, aircraft routing, crew pairing optimization, and crew assignment problem. In the operational viewpoint, we concern schedule recovery problems for aircrafts and crew using the method of reassigning available resources when airlines face with the unexpected situations.

• 한국항공운항학회지
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• 제29권2호
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• pp.47-54
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• 2021

Recently, the issue of maintaining pilot competency has emerged as one of the major challenges in the aviation industry due to irregular schedules and flight intervals caused by the global COVID-19. Therefore, a survey was conducted on airline pilots to determine how stressed they would be when returning to their flights after experiencing irregular schedules or long-term furloughs. The level of stress that pilots receive due to flight intervals was divided into periods, and correlation with general characteristics was identified to see what emotional burdens exist as the lengths of flight interval increased. As a result, burdened flight intervals and the Pilot Flying(PF) intervals were identified as a statistically significant variables. In the case of the Pilot Flying interval, the level of stress was confirmed to be worse as the flying interval was elongated, and in the case of the burdened flying interval, the tendency of the stress index were lower as the period increased. Through this study, pilots who experienced reduced flight times were found to be accompanied by considerable amount of emotional burden proportionate to the length of the interval period.

• 한국항공운항학회지
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• 제32권3호
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• pp.205-214
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• 2024

The aircraft delay rate has increased nearly three times in 2023 due to change in Korea policy of delay criteria. One of the primary causes of delays in domestic flights is related to reactionary delays, with Turnaround Time being a key factor. To mitigate reactionary delays and reduce aircraft delays, it is essential to establish an appropriate Turnaround Time and integrate it into flight schedules. This study aims to analyze the appropriate Turnaround Time for aircraft operating at Gimpo, Gimhae, and Jeju International Airports, which handle a high frequency of domestic flights. The research applies air traffic simulation, using variables such as current flight schedules, actual flight times, Turnaround Time, and flight routes to simulate actual conditions. Based on this analysis, the study seeks to identify the fitting Turnaround Time across various scenarios. The findings are expected to address reactionary delays and help reduce overall delay rates in domestic flights.

• 제어로봇시스템학회논문지
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• 제11권3호
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• pp.246-253
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• 2005

An experimenal study on flight control of high-speed AEV(Aero-levitation Electric Vehicle) scale model in wind-tunnel is conducted. The AEV is to fly at very low altitude in predesigned track so that it is always under the wing-in-ground effect. The experiment is intended to fly the scale model to follow the predesigned altitude schedule while holding its attitude (pitch, roll, and yaw). Especially, the altitude changes for climb, cruise, and descent with constant pitch angle are most important maneuvers. The experiment shows that the required mission flights can be performed with appropriate sensors, processors, and actuators.

• Journal of Astronomy and Space Sciences
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• 제31권1호
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• pp.51-61
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• 2014

In this work, the preliminary analysis on both the tracking schedule and measurements characteristics for the spacecraft on the phase of lunar transfer and capture is performed. To analyze both the tracking schedule and measurements characteristics, lunar transfer and capture phases' optimized trajectories are directly adapted from former research, and eleven ground tracking facilities (three Deep Space Network sties, seven Near Earth Network sites, one Daejeon site) are assumed to support the mission. Under these conceptual mission scenarios, detailed tracking schedules and expected measurement characteristics during critical maneuvers (Trans Lunar Injection, Lunar Orbit Insertion and Apoapsis Adjustment Maneuver), especially for the Deajeon station, are successfully analyzed. The orders of predicted measurements' variances during lunar capture phase according to critical maneuvers are found to be within the order of mm/s for the range and micro-deg/s for the angular measurements rates which are in good agreement with the recommended values of typical measurement modeling accuracies for Deep Space Networks. Although preliminary navigation accuracy guidelines are provided through this work, it is expected to give more practical insights into preparing the Korea's future lunar mission, especially for developing flight dynamics subsystem.

• 산업경영시스템학회지
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• 제43권4호
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• pp.116-122
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• 2020

Human and material resource planning is one representative example of Operations Research. Resource planning is important not only in civilian settings but also in military ones. In the Air Force, flight scheduling is one of the primary issues that must be addressed by the personnel who are connected to flight missions. However, although the topic is of great importance, relatively few studies have attempted to resolve the problem on a scientific basis. Each flight squadron has its own scheduling officers who manually draw up the flight schedules each day. While mistakes may not occur while drafting schedules, officers may experience difficulties in systematically adjusting to them. To increase efficiency in this context, this study proposes a mathematical model based on a binary variable. This model automatically drafts flight schedules considering pilot's mission efficiency. Furthermore, it also recommends that schedules be drawn up monthly and updated weekly, rather than being drafted from scratch each day. This will enable easier control when taking the various relevant factors into account. The model incorporates several parameters, such as matching of the main pilots and co-pilots, turn around time, availability of pilots and aircraft, monthly requirements of each flight mission, and maximum/minimum number of sorties that would be flown per week. The optimal solution to this model demonstrated an average improvement of nearly 47% compared with other feasible solutions.