http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
반도체 외장형 자체 테스트를 위한 임의 파형 생성기 구현
이창진,김동혁,안진호,Lee, Changjin,Kim, Donghyuk,Ahn, Jin-Ho 한국반도체디스플레이기술학회 2021 반도체디스플레이기술학회지 Vol.20 No.3
We introduce an arbitrary waveform generation method and its H/W implementation case based on Rademacher and Walsh function. According to the orthogonal and periodic features of Rademacher and Walsh function, simple calculations can generate arbitrary waves with affordable logics. We implemented an FPGA-based AWS using above two functions, and verified. HDL simulation shows the proposed idea can draw desired analog test waveforms very fast, and its H/W size is promising to Built-Out Self-Test(BOST) logics for AI ICs.
LES of Turbulent Mixing with splash plate in a Gas Generator
Changjin Lee(이창진),Sung-taick Lee(이성택) 한국항공우주학회 2008 한국항공우주학회 학술발표회 논문집 Vol.- No.-
LES analysis was conducted with in-house CFD code to investigate the turbulence evolution and interaction due to turbulence ring and splash plate in the gas generator. Though chemical reaction was not accounted for, the results can be useful in determining the turbulence characteristics generated by ring and plate. The calculation results show that the installation of turbulence ring can introduce additional turbulences and improve turbulent mixing in the downstream flow. However, the addition of splash plate in the downstream of TR brings totally different shape of perturbation energy and enstrophy distribution for turbulent mixing. This enhancement can be done by the formation of the intensively strong vorticity production and mixing behind the plate. Pressure drop was found to be a reasonable level of about I % or less of initial pressure in all calculation cases. Also, calculation results revealed that the variation of TR shape and intrusion length did not change the characteristics of turbulent mixing in the chamber. Even though the effect of installation location of splash plate on the turbulent mixing is not investigated yet, calculation results conclude the addition of splash plate leads to the increase in turbulent mixing with an acceptable pressure drop.
이창진(Changjin Lee),손채훈(Chae Hoon Sohn),이균호(Kyun Ho Lee),강상훈(Sang Hun Kang),변영환(Yung Hwan Byun),박수형(Soo Hyung Park) 한국추진공학회 2015 한국추진공학회 학술대회논문집 Vol.2015 No.5
한국추진공학회 연구회 사업으로 친환경 우주추진 시스템 연구회가 운영중이다. 본 논문에서는, 연구회 활동의 결과로서 한국형 달 탐사계획, 위성 추진 시스템 개발 현황, 친환경 추진제와 하이드라진 추진제의 비교, 우리나라에서 개발될 우주추진 시스템이 갖추어야 할 조건에 대하여 조사할 내용을 요약하였다. A Research Group of Green Space-Propulsion System is under activity in the frame of a research-group project supported by the Korean Society of Propulsion Engineers. In this paper, several items investigated by this research group are reviewed, which are a Korean plan of lunar exploration, the state-of-the art in the development of satellite propulsion systems, comparison of green propellants with hydrazine propellants, and requirements for space propulsion systems to be developed in Korea.
가속도 센서를 이용한 자동변속기 차량의 오르막 변속선도 개발에 관한 연구
이창진(Changjin Lee),권혁중(Hyugjoong Kwon),김성현(Sunghyun Kim) 한국자동차공학회 2017 한국자동차공학회 학술대회 및 전시회 Vol.2017 No.11
The conventional uphill pattern was developed through from a draft of the simulated pattern based on the vehicle performance and specifications to repetitive and calibration / evaluation on the public road. There was an inefficiency due to repetitive validation in various road conditions, also a difficulty to verify the developed pattern in the real road due to driving restriction depending on the road condition. In this study, new method proposed, which will improve the inefficiency, and cover all driving conditions. As a result, using an acceleration sensor in the flat road method developed and it showed 60% improvement in shift counts.