• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.34 no.4
• /
• pp.1-10
• /
• 2006

Separation motion analysis of staging system is conducted using combined analysis programs, which include unsteady aerodynamic analysis codes and dynamic motion analysis tools. In this study, the analysis is for the long-rang missile staging system. The purpose of this study is to verify the safety and reliance of the proposed staging system, and to find out the influence of angle of attack perturbation on staging. A structured parallel overset mesh called Chimera grid is used for the simulation of unsteady supersonic Euler flow solver. In addition, unsteady dynamic simulations are also performed.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2012.05a
• /
• pp.253-258
• /
• 2012

In this study, designs of the high efficiency composite propeller blade for a high speed turboprop aircraft, which will be used for a next generation regional commercial aircraft in Korea, are performed. Both the vortex theory and the blade element theory are used for preliminary aerodynamic design and performance analysis of the propeller. Then the aerodynamic design result is confirmed through performance analysis using a commercial CFD code, ANSYS. The carbon/epoxy composite materials is used, and the skin-spar-foam sandwich type structure is adopted for improvement of lightness and structural stability. Finally, it is investigated that the proposed propeller blade has high efficiency and structural safety through both aerodynamic and structural analysis and experimental test of a prototype propeller blade.

• Journal of Advanced Navigation Technology
• /
• v.27 no.1
• /
• pp.23-35
• /
• 2023

Evidence-based training (EBT) improves a pilot's competency and confidence based on the data(Evidence) from actual aircraft accidents, incidents, operations, and training for safe operation in the fast-paced and large-scale air transportation field. It is a training/assessment program that strengthens resilience for problem solving. As a way to apply this evidence-based training(EBT) to the educational system of ATO and to resolve the problems, I propose 3 improvement plans. They are evaluation criteria that apply the core competencies of EBT to the educational evaluation system, the way to improve the system for standardization of practical test examiners and instructors and also the ways to use Flight Simulation Training Devices(FSTD).

• Journal of Aerospace System Engineering
• /
• v.18 no.3
• /
• pp.65-69
• /
• 2024

This study aimed to analyze the structural integrity of a sensor control box, a critical component for real-time monitoring of brake chamber pressure in large commercial vehicles and trailers. We utilized the computational analysis program ANSYS Workbench R2021 based on our testing conditions and vibration test specification KS R1034. Through modal analysis, we identified resonance frequencies within the frequency range of 5 Hz to 100 Hz and compared results in the frequency range of 33 Hz to 67 Hz using harmonic analysis.

• Journal of Aerospace System Engineering
• /
• v.13 no.6
• /
• pp.52-59
• /
• 2019

The rotor blade is a key component that generates the lift, thrust, and control forces required for helicopter flight by the torque transmitted through the hub and the blade pitch angle control, and should be designed to factor vibration characteristics so that there is no risk of resonance with structural safety. In this study, the structural design of the main rotor blade for MPUH(Multi-Purpose Unmanned Helicopter) was conducted and the sectional stiffness measurement of the fabricated blade was performed. The evaluation of the vibration characteristics of the main rotor system was then conducted factoring the measured stiffness distribution. The interior of the rotor blade comprised of the skin, spar, and torsion box, and carbon and glass fiber composites were applied. The Ksec2D program was applied to predict the stiffness of blade, and the results were compared to the measured data. CAMRADII, a comprehensive rotorcraft analysis program, was applied to investigate the natural frequency trends and resonance risks due to the rotor rotation.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.40 no.2
• /
• pp.146-156
• /
• 2012

In-flight icing remains as one of the most persistent hazards for aircraft operations. The effect of icing on aircraft performance and safety has to be evaluated during the development and airworthiness certification process. The scaling method is a procedure to determine the scaled test conditions in icing wind tunnels in order to produce the same result as when the reference model is exposed to the desired cloud conditions. In this study, a scaling program is developed to provide an easy-to-use tool to the aero-icing community. The Olsen and Ruff 4th methods are employed for this purpose and the velocity is calculated by matching the dimensionless Weber number. To validate the program, the results are compared with the NASA scaling results. The scaling examples based on FAR (Federal Aviation Regulation) Part 25 Appendix C are also presented. Finally, a validation study using a state-of-the-art icing simulation code FENSAP-ICE is presented.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.40 no.3
• /
• pp.258-263
• /
• 2012

In this paper the Chemical Propulsion Subsystem of COMS is briefly explained and some telemetries acquired by a series operations of CPS during the Launch and Early Operation Phase of COMS are presented. The pressure and temperature of pressurant tank telemetries are compared with the results of the developed computer program. The changes in pressure are due to the two major phases. The first one is the initialization phases of CPS composed of the venting phase to vent the helium gas in the pipe network from the downstream of the propellant tanks to the thrusters for safety, the priming phase to fill the vented pipe network with oxidizer and fuel respectively and then the pressurization phase to pressurize the ullage of propellant tank to regulated pressure. And the other is the apogee engine firings in which COMS CPS is in the orbit raising phase to use helium as a pressurant to keep the pressure of propellant tank as the liquid apogee engine get fired until COMS reached to the target orbit. This program can be applicable to prepare basis design data of the next Geostationary Satellite CPS.

• Journal of Aerospace System Engineering
• /
• v.12 no.1
• /
• pp.47-56
• /
• 2018

In this paper, the structural analysis of the Geostationary Korea Multi-Purpose Satellite-2 (GEO-KOMPSAT-2) tubing system is discussed, and the structural integrity of the tubing system is assessed by comparative analysis with the results of overseas partner AIRBUS. Securing structural reliability of the tubing system is a very important key element of the propulsion system of the GEO-KOMPSAT-2 satellite. Therefore, FE modeling of the propulsion tubing was carried out directly using the CAE program, and structural analysis was performed to evaluate the stress state under launch conditions. Hoop stress, axial stress, bending stress, and torsion stress were calculated according to diverse load conditions by using pressure stress analysis, thruster alignment analysis, sine qualification load analysis, and random qualification load analysis. From the results, the Margin of Safety (MoS) of the tubing system is evaluated, and we can verify the structural integrity of the tubing system when subjected to various launch loads.

• Annual Conference of KIPS
• /
• 2010.04a
• /
• pp.796-799
• /
• 2010

인터넷의 발전으로 인터넷을 통한 서비스가 증대하고 있다. 반면 응용 소프트웨어의 보안 취약점으로 인해 국가, 기업, 개인 모두에게 정보보호의 중요성이 더욱 강조 되고 있다. 임베디드 소프트웨어인 우주, 항공, 원자력 소프트웨어 등 오류 없이 수행되어야 하는 고안전성 소프트웨어의 개발기법은 이제 응용 소프트웨어의 보안강화 활동에 활용 되고 있다. 특히 시큐어 코딩 (Secure Coding)은 방어적 프로그램(Defensive Programming)을 포함하는 개념으로 소프트웨어의 안전성과 보안성을 향상 시킬 수 있다. 본 논문에서는 범용 보안 취약가능성 분석 도구를 이용하여 소프트웨어의 취약 가능성을 분석하고 보안 취약점 유발 명령어를 분류한다. 그 다음에 시큐어 코딩 기법을 적용하여 취약한 코드를 개선하였다. 이러한 개선을 통해 보안 취약성 가능한 코드 부분을 손쉽게 수정하여 소프트웨어 보안을 개선할 수 있다.

• Annual Conference of KIPS
• /
• 2023.11a
• /
• pp.1090-1091
• /
• 2023

최근 자동차와 항공 산업에서는 승객들의 편의에 맞추어 엔터테인먼트 서비스를 선보이고 있다. 선행 연구에 따르면, 이동 시간대 스마트폰으로 프로그램을 이용하는 동기로는 '오락용'(19.8%), '소통용(SNS)'(18.8%), '정보용'(15.0%), '게임용'(6.8%)로 전체의 60.4 %를 차지한다. 이는 콘텐츠와 커뮤니티 이용 및 정보탐색 등으로 이동 중 지루한 시간을 해소한다는 유의미한 통계를 보여준다. 해상 분야에서도 정보와 오락 기능을 결합해 편리한 항해를 지원할 필요가 있다고 사료된다. 본 논문은 인터넷 통신이 어려운 선박에서도 무선 통신망을 이용하여 미디어 콘텐츠 및 커뮤니티 활성화뿐만 아니라 안전사고 발생 시 신속하고 정확한 정보 전달 등을 목표로 삼는 선박 인포테인먼트 시스템을 제안하고자 한다.