• Bulletin of the Korean Space Science Society
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• 2004.04a
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• pp.80-80
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• 2004

해상도가 높아질수록 위성 탑재 카메라의 광학적 설계 조건은 까다롭다. 특히 1m급의 고해상도 영상을 얻기 위해서는 개념설계 단계에서부터 여러 가지 기술적인 면과 운용적인 면을 동시에 고려해야 하며 이러한 조건들이 상호 연관성을 가지면서 광학계의 형태나 성능을 결정하므로 다양한 해석과 분석이 필요하다. 해상도, 촬영고도, 관측폭 그리고 촬영소자의 크기에 의해 광학계의 초점거리가 결정되며 광학계의 유효구경을 추가하면 신호량 성능에 대한 예측이 가능하다. (중략)

• Composites Research
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• v.17 no.4
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• pp.82-86
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• 2004

철도차량에서 복합재료에 대한 활용은 날로 증대되고 있는 추세이다. 현저한 기술적 진보를 얻기 위해 철도차량은 더 가볍고, 강하고, 안전하며 전통적인 소재와는 차별화된 소재를 요구하고 있다. 복합재료의 철도차량에의 응용은 무게 감소, 이로 인한 속도 증가, 에너지 소비량 감소, 낮은 관성, 적은 트랙 마모 그리고 큰 유효 탑재량 등의 장점을 지니고 있으며 철도차량 디자인에 여러 다양함을 제공하고 낮은 무게 중심 설계에 의한 안전성 확보, 단순화된 구조 설계에 의한 좌석수의 증가 등의 장점을 지니고 있다. 또한, 모듈화 설계를 가능케 함으로서 제작공정의 감소 및 유지보수 효율화를 얻을 수 있게 된다. (중략)

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.05a
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• pp.207-210
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• 2009

This paper presents development status of sounding rockets containing scientific payload and telemetry at home and abroad. The case of outside, united state is launching sounding rockets in 20-30 flight per year by the NASA program which offer to carry payload weights of 38-680 kg and altitude of 88-1,500 km. Europe is launching in 4-5 flight per year by the ESA program. Japanese sounding rockets are being applied an Antarctic exploration and flight verification in 1-2 flight per year. The case of korean sounding rockets was successful with the launch of three times(KSR-I,II,III), but our development techniques for space launch vehicle lag behind other industries. Therefore, Launch vehicle development should enable with the support and acquirement of advanced technology.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.04a
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• pp.466-475
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• 2011

This paper presents development status of sounding rockets containing scientific payload and telemetry at home and abroad. The case of outside, United States is launching sounding rockets in 20-30 flights per year by the NASA program which offers to carry payload weights of 38-680 kg and altitude of 88-1500 km. Europe is launching in 4-5 flights per year by the ESA program. The case of Korean sounding rockets was successful with the launch of three times(KSR-I,II,III), but Korea lags far behind the advanced countries in the field of development technologies for space launch vehicle. We expect that our scientific and industrial technologies will be improved through the research and development of sounding rockets. In this study we proposed necessity and future direction of development in domestic sounding rockets.

• Journal of the Korean Society of Propulsion Engineers
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• v.15 no.3
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• pp.70-79
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• 2011

This paper presents development status of sounding rockets containing scientific payload and telemetry at home and abroad. The case of outside, United States is launching sounding rockets in 20-30 flights per year by the NASA program which offers to carry payload weights of 38-680 kg and altitude of 88-1500 km. Europe is launching in 4-5 flights per year by the ESA program. The case of Korean sounding rockets was successful with the launch of three times(KSR-I,II,III), but Korea lags far behind the advanced countries in the field of development technologies for space launch vehicle. We expect that our scientific and industrial technologies will be improved through the research and development of sounding rockets. In this study we proposed necessity and future direction of development in domestic sounding rockets.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.12
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• pp.1859-1867
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• 2021

Multi LiDAR sensors are being mounted on autonomous vehicles, and a system to multi LiDAR sensors data is required. When sensors data is transmitted or processed to the main processor, a huge amount of data causes a load on the transport network or data processing. In order to minimize the number of load overhead into LiDAR sensor processors, only semantic data is transmitted through data comparison between frames in LiDAR data. When data from 4 LiDAR sensors are processed in a static environment without moving objects and a dynamic environment in which a person moves within sensor's field of view, in a static experiment environment, the transmitted data reduced by 89.5% from 232,104 to 26,110 bytes. In dynamic environment, it was possible to reduce the transmitted data by 88.1% to 29,179 bytes.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.10
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• pp.1031-1037
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• 2010

This paper proposed lightweight aluminum bipolar plates as an alternative for conventional graphite bipolar plates in fuel cell systems used as a power source for small reconnaissance UAVs. Since bipolar plates occupy more than 80% of the total weight of the fuel cell system, lightweight aluminum bipolar plates can improve the overall payload and flight time of the fuel cell UAV. The aluminum and graphite bipolar plates were fabricated to compare the performance of each of them. A 15% higher performance per weight was obtained from aluminum bipolar plates than the graphite bipolar plates. Also, the performance of a single cell using aluminum bipolar plates was evaluated under various operating conditions.

• Proceedings of the KIPE Conference
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• 2018.11a
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• pp.33-35
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• 2018

본 논문에서는 전기자동차에 탑재된 배터리의 최대 출력 전류 산출을 위한 실시간 셀 스크리닝 알고리즘을 제안한다. 알고리즘을 통하여 배터리 팩을 구성하는 셀들 중 필수적으로 관리해야 할 셀을 선별하고 이를 최대 출력 전류 추정에 사용함으로써 안전성을 확보함과 동시에 연산량을 줄여 BMS의 부담을 완화하고 관리의 효율을 증대한다. 제안된 알고리즘은 시뮬레이션을 기반으로 유효성을 검증한다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.4
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• pp.306-314
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• 2018

A two-axis gimbal-type X-band antenna for CAS(Compact Advanced Satellite) transmits large amount of image data to ground station regardless of satellite attitude and orbital motion. This antenna mounted on the external surface of the satellite is directly exposed to the extreme space with thermal environment during the orbital operation. Therefore, a proper thermal design is needed to maintain the antenna itself as well as other main components within allowable temperature range. In this study, the thermal design effectiveness of two-axis gimbal X-band antenna was verified through the thermal analysis. In addition, required power and duty cycle of heater were estimated through the thermal analysis under conditions of system level thermal vacuum test and on-orbit thermal environment. The thermal analysis results indicated that all the main components of X-band antenna satisfy the allowable temperature requirement.

• Journal of the Korean Institute of Gas
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• v.22 no.3
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• pp.45-52
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• 2018

As guidelines for exhaust gases of ship are reinforced by the International Maritime Organization, the necessity for LNG fuelled ship is emerging. The relevant research is actively progressing to develop technologies and promote commercialization. When the residual quantity of LNG fuel tank is less than 70% by consuming fuel during operation, sloshing should be considered. We applied the Type C LNG fuel tank because medium sized LNG fuelled ships are difficult to equip with re-liquefaction system. Structural integrity and thermal performance are very important, especially in LNG fuel tanks that apply to LNG fuelled ship. Through this study, we proposed evaluation procedure of thermal performance for the Type C LNG tank, and verified the validity and effectiveness of BOR(Boil-Off Rate) test Procedure by comparing and analyzing changes in temperature, pressure, BOG(Boil-Off Gas).