• The Bulletin of The Korean Astronomical Society
• /
• v.37 no.2
• /
• pp.181.2-181.2
• /
• 2012

우주공간에서는 solar particle과 galactic cosmic ray에 포함된 proton, electron 및 heavy ion등에 의해 radiation 현상이 발생하는데 이는 각종 전자장비의 성능 감쇄 및 디지털 장비의 내부 정보를 교란을 야기할 수 있다. 특히 메모리의 bit 정보가 반전되는 Single Event Upset (SEU)의 경우 인공위성 및 우주정거장 등의 시스템에서도 빈번히 발생할 수 있으며 적절한 조치가 이루어지지 않으면 주어진 임무 수행 실패는 물론 시스템 failure까지 이를 수 있다. 따라서 SEU에 의한 문제 발생 시 신속한 문제 확인 및 대처가 매우 중요하다. 본 논문에서는 SEU의 발생 원인 및 영향과 기존의 오류 검출 및 수정 기법에 대해 소개하도록 한다. 또한 효율적이고 신뢰성 있는 설계를 위해 각 하드웨어 소자 특성에 따른 적합한 SEU 회피 방안을 제시하도록 한다.

• Aerospace Engineering and Technology
• /
• v.6 no.1
• /
• pp.173-181
• /
• 2007

Radiated emission / susceptibility performance of the KSLV-I 2nd stage which are controlled from the unit level to the system level should be examined and managed all over the frequency ranges in order to ensure the normal operation of the SC, the 1st stage of the KSLV-I, ground support equipments which are installed at the space center, and other wireless communication networks. Not only unintentional electric field emissions from the KSLV-I system and its subsystems should be restricted to the levels less than the limits specified in the EMC requirements, but also proper test and evaluation method should be established, respectively. In this paper, radiated emission/susceptibility test limits, method, and test results of the KSLV-I 2nd stage engineering model are presented.

• Current Industrial and Technological Trends in Aerospace
• /
• v.8 no.2
• /
• pp.54-64
• /
• 2010

A spacecraft contends with various vibration from the launch to the on-orbit operation, which is one of the major considerations in spacecraft design. The weight reduction has been indispensable to decrease the launch cost, however it produces worse disturbances for the spacecraft equipments. Besides, the load requirements at observation payload interfaces have became severe to secure their pointing stability as their images are required with high resolution. As a possible solution, a vibration isolation system is introduced and it reduces the vibration from the launch vehicle or isolates the spacecraft equipments from their generating/transmitted vibration. In this paper, it is examined the design consideration needed for the accommodation of the vibration isolation systems through the survey of recent applications of vibration mitigation technologies to spacecrafts.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.46 no.6
• /
• pp.513-518
• /
• 2018

Nitrogen charging trailer applied to KUH-1 is a device to charge Nitrogen in main front wheel buffer, tail bumper buffer, brake accumulator and tire of aircraft. As the name suggests, it is a device that has mobility along with nitrogen charging. Originally supplied by Tronair in the United States, it was imported from Korea, and the locally developed product not only satisfies the performance of the existing product, but also designed to be easier than the product introduced in the operation. It was selected as the joint investment project of the 15th civilian government building, and development needs analysis and test evaluation were carried out under the support of development and management of Korea Aerospace Industries and Defense Agency for Technology and Quality.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.32 no.6
• /
• pp.134-141
• /
• 2004

The three-dimensional precision measurement technology for industrial product of middle and/or large scale has been developed. Theodolite measurement system which is one of the technology is widely used in aerospace industry. This paper describes a range alignment method of parabolic antenna to RF probe in the near field range by using the theodolite system, The range alignments of the Ku-band and Ka-band antennas have been accomplished within the requirements, ${\pm}1mm\;and\;{\pm}0.05^{\circ}$.

• The Bulletin of The Korean Astronomical Society
• /
• v.37 no.2
• /
• pp.152.2-152.2
• /
• 2012

우주발사체 발사를 위해서는 발사대시스템 개발이 필수적이다. 발사대시스템은 기계설비와 추진제공급설비, 관제설비로 구성되며, 그 중 기계설비는 발사지지대(Launch Pad), 이렉터(Erector), 트랜스포터이렉터(Transport-Erector), 케이블마스트(Cable-mast), 자동체결장치(Auto-coupling Device) 총 다섯 부분으로 나눌 수 있다. 발사지지대는 발사 전까지 발사체를 지지하는 구조물로 발사체의 안전을 보장하고 공급배관 및 통신라인의 경로를 제공한다. 이렉터는 발사준비과정에서 수평으로 이송된 발사체를 2개의 대형 유압실린더를 사용하여 기립시키는 장비로 발사 취소 시 발사체를 수평으로 전환한다. 트랜스포터이렉터는 조립공간에서 조립을 마치고 최종점검이 완료된 발사체를 전용차량을 이용하여 발사대로 이동하고 발사체를 안전하게 잡아준다. 자동체결장치는 지상으로부터 발사체로 연결되는 추진제, 압축가스 등의 연결배관을 자동으로 연결/분리하는 장치이다. 케이블마스트는 우주발사체 상단부의 UCU-E(Umbilical Connectors Unit-Electrical)를 통해서 전기, 고압가스, 고온공기 등을 공급하기 위한 통로로 발사 전까지 발사체시스템과 지상장비와의 통신수단이다. 또한 발사체로 연결되는 라인들을 발사 시에 나오는 후류에 의한 충격으로부터 보호하고, UCU-E가 기계적으로 분리되도록 구성되어 있다. 본 논문은 기존에 적용된 케이블마스트에 대한 구성, 기능 및 운용절차에 관한 것으로, 현재 진행 중인 한국형발사체 개발을 위한 기초 자료조사로 활용하고자 한다.

• Aerospace Engineering and Technology
• /
• v.6 no.1
• /
• pp.222-229
• /
• 2007

Environmental tests should be carried out to show that design performance is in an operational condition in an actual operational environment to assure maintainability and reliability. Aero-products electromagnetic compatibility tests are performed mainly for the individual parts and Specifications MIL-STD-461E and RTCA DO-160E are developed for the military and commercial parts tests respectively. The MIL-STD-461E which is a military environmental test standard is targeting all munitions and that user can apply by selecting applicable requirements from this specification. On the other hand, requirements are applied exclusively for the Avionics Equipments in commercial test standard.

• Journal of Aerospace System Engineering
• /
• v.10 no.4
• /
• pp.84-89
• /
• 2016

Electronic Warfare (EW) is the mission area responsible to establish and maintain a favorable position in the electromagnetic domain. Testing and Evaluation of EW devices on modern military aircraft to pursue this critical mission area require the use of a wide range of techniques and analytical methods to assure users of the readiness of EW system to meet the challenge of a combat environment. This paper is intended as an introductory text dedicated to EW systems (especially RWR, CMDS) test and evaluation techniques and will serve experienced engineers and program managers, as well as novice engineers, as a concise reference for EW systems' test and evaluation processes and testing resources.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.33 no.3
• /
• pp.71-77
• /
• 2005

An unmanned aerial vehicle (UAV) is generally flied via a pre-planned flight path or real-time commands by an operator. To succeed in an assigned mission, analysis such as the line-of-sight analysis for communication between UAV and a ground data terminal should be performed. In this paper, various analysis algorithms which are performed by a ground control station in pre-flight and in-flight phases, are proposed for the safe flight of UAV. Note that the proposed algorithms can be applied to most UAV systems.

• Aerospace Engineering and Technology
• /
• v.7 no.1
• /
• pp.236-244
• /
• 2008

The evolution and application of RFID technologies have been at the forefront of allowing aviation industries to improve the quality of aircraft maintenance and air cargo handling. However, safety problems in airplane operation are arising from the hazards of frequencies transmitted due to RFID systems. Though the intensities of frequencies back-scattered from the tags are very weak, some malfunctions are anticipated due to induction coupling on aircraft wiring. Therefore, safety assessment such as electromagnetic compatability should be accomplished upon aircraft critical and essential equipments before installations.