APMS 활용을 통한 항공기 연비향상 및 기대효과

유재림 한국항공운항학회 2023 한국항공운항학회지 Vol.31 No.2

SHM (Structural Health Monitoring) technique for monitoring aircraft structural health and damage, EHM (Engine Health Monitoring) for monitoring aircraft engine performance, and APM (Application Performance Management) is used for each function. APMS (Airplane Performance Monitoring System) is a program that comprehensively applies these techniques to identify the difference between the performance manual provided by the manufacturer and the actual fuel mileage of the aircraft and reflect it in the flight plan. The main purpose of using APMS is to understand the performance of each aircraft, to plan and execute flights in an optimal way, and consequently to reduce fuel consumption. First, it is to check the fuel efficiency trend of each aircraft, check the correlation between the maintenance work performed and the fuel mileage, find the cause of the fuel mileage increase/decrease, and take appropriate measures in response. Second, it is to find the cause of fuel mileage degradation in detail by checking the trends by engine performance and fuselage drag effect. Third, the APMS is to be used in making maintenance work decisions. Through APMS, aircraft with below average fuel mileage are identified, the cause of fuel mileage degradation is identified, and appropriate corrective actions are determined. Fourth, APMS data is used to analyze the economic analysis of equipment installation investment. The cost can be easily calculated as the equipment installation cost, but the benefit is fuel efficiency improvement, and the only way to check this is the manufacturer's theory. Therefore, verifying the effect after installation and verifying the economic analysis is to secure the appropriateness of the investment. Through this, proper investment in fuel efficiency improvement equipment will be made, and fuel efficiency will be improved.

운송용 항공기 연료탑재 최적화 방안

유재림 청주대학교 산업과학연구소 2022 産業科學硏究 Vol.39 No.2

The fuel consumption of each aircraft was corrected using APMS and navigation systems and weather forecasting technology were developed to make the flight plan more accurate, and as a result, it became similar to the actual fuel consumption. In addition, the reliability of the flight plan will be higher by loading the actual taxi out fuel and the difference in actual trip fuel compared with the planned trip fuel. In this study, I present the optimal fuel loading for trip fuel, destination alternate fuel, contingency fuel, final reserve fuel, taxi out fuel and discretionary fuel. This leads to a significant reduction in fuel consumption and carbon emission by fuel weight management. This further enhances the international competitiveness of national companies and enables energy savings, and plays an important role in ESG.

Preparation and Characterization of Polymer/Carbonyl Iron Composite Microspheres

유재림,최형진 한국고분자학회 2006 한국고분자학회 학술대회 연구논문 초록집 Vol.2006 No.4

전방향 셀프-밸런싱 로봇휠체어 개발

유재림,박윤수,김상태,권상주 한국로봇학회 2013 로봇학회 논문지 Vol.8 No.4

In this paper, we report a self-balancing robot wheelchair which has the capability of keeping upright posture regardless of the terrain inclination in terms of the three dimensional balancing motion. It has the mobility of five degrees of freedom, where pitching, yawing, and forward motions are generated by the two-wheeled inverted pendulum mechanism and the rolling and vertical motions are implemented by the movement of the tilting mechanism. Several design considerations are suggested for the sliding type vehicle body, wheel actuator module, tilting actuator module, power and control system, and the riding module.

이륜 밸런싱 모바일 로봇의 비평탄면 주행을 위한 외란 관측기 설계

유재림,권상주 제어로봇시스템학회 2015 제어로봇시스템학회 국내학술대회 논문집 Vol.2015 No.5

이륜 밸런싱 로봇에 대한 비선형 모델 기반 외란보상 기법

유재림(Jaerim Yu),김용국(Yongkuk Kim),권상주(SangJoo Kwon) 제어로봇시스템학회 2016 제어·로봇·시스템학회 논문지 Vol.22 No.10

A two-wheeled balancing mobile robot (TWBMR) has the characteristics of both nonlinear and underactuated system. In this paper, the disturbances acting on a TWBMR are classified into body disturbance and wheel disturbance. Additionally, we describe a nonlinear disturbance observer, which is suitable as a single input multi-output (SIMO) system for the longitudinal motion of TWBMR. Finally, we propose a reasonable disturbance compensation technique that combines the indirect reference input of equilibrium point and the direct torque compensation input. Simulations and experimental results show that the proposed disturbance compensation method is an effective way to achieve robust postural stability, specifically on inclined terrains.

미니멀 커뮤니케이션의 시각적 모호성 연구

유재림(Jereem You),전수진(Soojin Jun) 한국HCI학회 2014 한국HCI학회 학술대회 Vol.2014 No.2

지금까지 대체적으로 미니멀리즘을 순수하며, 단순하게 명확하고 정확환, 군더더기가 없는 것으로 생각해왔다. 명확하고 이성적이며 합리적인 것은 그 목적의 달성에 적합하지만 대신 그 것이 또한 울타리가 되어 확장성이 결여되어 사고의 틀을 작아지게 할 수 밖에 없다. 하지만 그만큼 주어진 것에 대한 정보를 전달하는 매개체가 미니멀화되면서 그에 따라 모호성은 나타나기 마련이다. 그렇기 때문에 뚜렷하게 그 의미를 전달하는 경우를 제외하면, 모호성을 가진 커뮤니케이션은 시간이 다소 소요되더라도 사고의 틀을 확장하는데 기여하는 바가 크다. 특히 UI와 같은 인포메이션 부분에서 과거의 개념으로 Easy & Clear가 강하게 자리잡고 있어서 모호적 커뮤니케이션이 잘못됐다고 생각하기 쉽지만, 감성적인 측면에서 바라본다면 그 이야기는 달라질 수 있다고 볼 수 있다. 여기서 바로 다양한 분야에서 유효할 수 있는 미니멀 디자인이 가지고 있는 모호성의 가능성에 대해서 이야기 해보고자 한다. In general, Thought it minimalism is pure, simple and clear accurate things. It is suitable for achieving the objective. But, also It can be a limitation and lack of scalability and makes frame of thinking smaller. Accordingly, There appears to ambiguity as much again when the communication medium be minimal. Even if it a time-consuming job, It communication with ambiguity contributes to high, except what transmit meaning clearly. Easy & clear is a old concept. In particular, place in part of the information likes UI. so It is easy to think of “Ambiguous communication is wrong”. But The story can be different when look at that emotional side. So This paper research about “The potential of ambiguity in minimal design can be effective in various fields”.

CFIT 자율 회피를 위한 심층강화학습 기반 에이전트 연구

이용원,유재림 한국항공운항학회 2022 한국항공운항학회지 Vol.30 No.2

In Efforts to prevent CFIT accidents so far, have been emphasizing various education measures to minimize the occurrence of human errors, as well as enforcement measures. However, current engineering measures remain in a system (TAWS) that gives warnings before colliding with ground or obstacles, and even actual automatic avoidance maneuvers are not implemented, which has limitations that cannot prevent accidents caused by human error. Currently, various attempts are being made to apply machine learning-based artificial intelligence agent technologies to the aviation safety field. In this paper, we propose a deep reinforcement learning-based artificial intelligence agent that can recognize CFIT situations and control aircraft to avoid them in the simulation environment. It also describes the composition of the learning environment, process, and results, and finally the experimental results using the learned agent. In the future, if the results of this study are expanded to learn the horizontal and vertical terrain radar detection information and camera image information of radar in addition to the terrain database, it is expected that it will become an agent capable of performing more robust CFIT autonomous avoidance.

쌍발기 대비 A380 연료효율성 비교 분석 연구

장성우,유재림,유광의 한국항공경영학회 2022 한국항공경영학회지 Vol.20 No.3

At the beginning of the operation of the A380, it was expected that the A380 would replace the conventional aircraft with its excellent fuel efficiency and carbon reduction effect. The A380 is efficient when full passenger on board for long-haul routes. However, the commercial aviation landscape has changed dramatically over the past two to three years, and the demand for larger aircraft such as A380 and B747 has disappeared. As oil prices rise, airlines increasingly want to operate high-efficiency aircraft, and manufacturers are developing and supplying twin-engine aircraft such as the A350 and B787, which are capable of longdistance flights and have improved fuel efficiency. As a result of the COVID-19 outbreak, most airlines operating the A380 have suspended the operation of the A380. Currently, the A380 is temporarily operated due to the surge in travel demand. In the long term, the controversy regarding the economic analysis of the A380 operation will continue. In this study, the fuel efficiency of A380 and A350 was comparatively and evaluated. Using actual flight data of A380 and A350, the superiority and inferiority of fuel efficiency were presented with specific figures. Using the fuel efficiency prediction model established in this study, two cases of the same payload and the same load factor were compared. Based on the same payload, the fuel efficiency of the A350 was about 2.0 times higher than that of the A380. Based on the same load factor, the fuel efficiency of the A350 was about 1.35 times higher than that of the A380. Although the difference in fuel efficiency between the two aircraft was reduced, it was confirmed that the fuel efficiency of the latest twin-engine A350 was quite excellent, and it was evaluated that the A380 aircraft had room to compete with the A350 only when close to full passengers were on board. The economics of A380 operation was analyzed by expanding from the technical concept of fuel efficiency to the airline management concept of benefits and costs. However, in order to quantify detailed benefits and costs, there are limitations in that airlines’ own business policies and purchase contracts must be confirmed, and time series predictions of external variables such as crude oil prices and exchange rates must be studied in advance. Exact economic analysis is left as a future study, and in this study, the economic analysis of A380 operation was confirmed at a general level as a result of fuel efficiency comparison. The unit cost excluding fuel cost is assumed to be the same. CASK (Cost per Available Ton Kilometer), which is the cost of flying 1km per passenger, is higher in the A380 than in the A350. On the other hand, the economics of operating the A380 is determined by the RASK (Revenue per Available Ton Kilometer), which is the profit earned when flying 1km per passenger. If the RASK of A380 exceeds 1.35 times that of the A350, the A380 is considered to have a competitive compared with the A350. If the A380’s RASK exceeds the A380’s own CASK, the A380 can continue to operate. Airline must maintain ‘RASK > CASK’ of A380. It is necessary to increase RASK by increasing passenger ticket, cargo transportation, and in-flight duty-free sales, while reducing CASK by reducing cost.

성능향상 패키지 적용 효과 분석 - Airbus 350 기종을 중심으로 -

장성우,조율현,유재림,유광의,Jang, Sungwoo,Cho, Yul Hyun,Yoo, Jae Leame,Yoo, Kwang Eui 한국항공운항학회 2021 한국항공운항학회지 Vol.29 No.3

PIP is an abbreviation of 'Performance Improvement Package', which is a package that can improve performance by applying some design changes to existing aircraft. Boeing provides PIP applicable to B777-200, and Airbus provides PIP applicable to A350-900 as standard. PIP provided by Boeing and Airbus is a separate task, but it is expected to reduce fuel consumption by reducing drag through aerodynamic improvements. The PIP applied to the A350-900 includes work such as increasing Winglet Height and re-twisting Outboard Wing. This study is to verify the effect of PIP application of the A350-900 aircraft and use it as basic data for economic analysis. The aerodynamic improvement studies and expected effects of the PIP application were examined, and the actual flight data of the PIP-applied and the non-applied aircraft were compared to confirm the PIP application effect. This paper provides empirical results for the aviation industry on the PIP application efficiency as a method of improving fuel efficiency and reducing carbon emission.