주의 분배력 분석을 통한 조종사 선발 방법에 관한 연구

이달호,Lee Dal-Ho 한국국방경영분석학회 1985 한국국방경영분석학회지 Vol.11 No.1

This study develops a scientific method in pilot selection by analysing a divided attention performance between the successful pilots and the failures in a flight training course. To measure the divided attention performance, Dual Task Method is used in which the primary task is a tracking task while the secondary tasks are, 1. short-term memory task 2. choice reaction task 3. judgement task. Result shows that the performance of the pilots is significantly better (p < 0.1) than that of the failures in divided attention performance. In addition, the differences in the divided attention performance between the two groups are increased in proportion to the difficulty of the task and especially in the short term memory, the increment is most dramatic.

비행안전 프로그램으로서의 생체 활성도 활용방안 연구

이달호,최승호,Lee, Dal-Ho,Choe, Seung-Ho 대한인간공학회 1998 大韓人間工學會誌 Vol.17 No.3

Aircraft and the three-dimensional environment in which they operate are not user-friendly for human beings. As a result, maintaining the proficiencies necessary to safely and efficiently fly an airplane are difficult, and costly. The physiological and emotional status of the human element remains crucial in maintaining safe performance by all crew members. In the study of Hagiwara et al.(1993). they called the physiological and emotional status of the human element into the human alertness or physiological activity and stress, fatigue, circadian rhythm, alcohol. smoking, and self-medication are known the major factors that deteriorate the human alertness. Accordingly. this paper deals with the quantitative and objective performance test based on tracking error and reaction time by means of the new computer test program into which the perception-motion system of human beings is applied. Throughout this experiment using performance test, the results suggest that performance capability in state of sleep deprivation 2 hours and alcoholic 0.05~0.06% in blood were more impaired than one in a normal state, and they further showed statistically significant differences between them, which were influenced by impairment factors of body regulation and pilot's grade. We also obtained the prediction value and the 95% confidence interval of tracking error and reaction time at the normal state for the purpose of distinguishing performance capability between the normal state and the abnormal state. And it is expected that the evaluation of human alertness using performance test will be applied to the quantitative assessment of an each pilot's realistic consciousness/attention, and will lead a flight commander to the accurate decision of mission approval prior to a flight.

최신 Laser system을 이용한 direct resin restoration

이달호,국정화,Lee, Dal-Ho,Guk, Jeong-Hwa 대한심미치과학회 2006 Journal of the Korean Academy of Esthetic Dentistr Vol.15 No.2

비행시험 데이타를 이용한 전술용 미사일의 공력계수 추정

이달호(Dal-Ho Lee),이장규(Jang G. Lee) 한국항공우주학회 1985 한국항공우주학회 학술발표회 논문집 Vol.- No.-

고압전동기용 진동 감시 시스템을 위한 특징 파라미터 추출기법 개발

이달호(Dal-Ho Lee),박정철(Jung-Cheul Park) 한국정보전자통신기술학회 2019 한국정보전자통신기술학회논문지 Vol.12 No.4

본 논문에서는 회전체의 특징 파라미터들을 추출하기 위한 센서의 신호들을 수집하는 방법을 연구하고자 한다. 이를 위해, 모형 시험을 수행하기 위한 진동 테스트 리그를 개발하여 정상적으로 운전하에서의 신호특성을 분석하였다. 다른 진동 요소들로부터 주기적인 충격에 의해 발생되는 진동 성분을 추출하기 위하여 포락 신호처리(Envelope FFT Analysis) 기법을 사용하였다. 회전속도에 따른 신호분석과 더불어 회전체의 저주파수 특성을 잘 나타내는 속도센서 및 진동 테스트 리그의 부하변화에 따른 신호를 분석하였다. 그 결과, 베어링 하우징에서 측정되는 가속도 신호는 진폭이 작으며 조화 성분과 모터의 회전주파수 성분만이 발생함을 확인하였다. 즉, 회전수가 높아짐에 따라 가속도의 진폭이 높아짐을 확인할 수 있었다. 회전속도가 증가하면 원 데이터의 형상의 차이가 있는 것을 확인할 수 있었고, 가속도 FFT 그래프와 비교하였을 경우 저 주파수에서 노이즈에 강하며 해당 회전 주파수 성분을 뚜렷하게 나타내었다. 또한 부하를 변화시켜도 주요 회전 주파수 성분이 증가하지 않음을 알 수 있었다. This paper aimed at collecting sensor signals to extract characteristic parameter of the rotor. A vibration test rig has been developed to perform model tests. Signal characteristics were analyzed when driving normally. Envelope FFT Analysis is used to extract vibration components caused by periodic impacts from other vibration factors. Signal analysis was performed when load changes were given to speed sensors and vibration test rigs that show low frequency characteristics of the rotor and signal analysis according to rotational speed. The acceleration signal measured in the bearing housing has a small amplitude and produces only the rotational frequency component and harmonic component of the motor. As the number of rotations increases, the amplitude of acceleration can be seen. As the rotational speed increases, it can be seen that there is a difference in the shape of the original data and compared with the acceleration FFT graph, it can be seen that the noise is strong at low frequencies and the corresponding rotational frequency components are clearly represented. It can be seen that changing the load does not increase the main rotational frequency component.

ANSYS 프로그램을 이용한 풍력발전에 관한 연구

이달호(Dal-Ho Lee),박정철(Jung-Cheul Park) 한국정보전자통신기술학회 2018 한국정보전자통신기술학회논문지 Vol.11 No.5

본 논문은 주 블레이드를 V 형태로 설계하고 주 블레이드와 보조 블레이드의 매수를 변화시켜 최상의 설계조건을 확인하고자 한다. 출력과 효율은 주 블레이드 매수가 증가할수록 증가되었다. sample 2는 sample 1과 비교하면 출력이 50% 상승하였다. sample 3은 92.8%, sample 4는 114.2% 정도 상승하였으며, 효율은 sample 1과 비교하여 sample 2는 38.4%, sample 3과 sample 4는 각각 92.3%, 107.7% 상승하였다. 보조 블레이드 매수를 증가 할수록 출력과 효율이 증가되었다. sample 6은 sample 5와 비교하면 출력이 33.3% 증가하였고. sample 7은 42.1% 증가하였다. 효율은 sample 5와 비교하여 sample 6은 35.3%, sample 7은 47.1% 정도 증가되었다. 보조 블레이드와 주 블레이드를 각각 30매로 하였을 때(sample 8) 가장 높은 출력과 효율이 측정되었다. sample 8은 sample 4와 비교하면 출력은 5.6% 및 효율은 3.7% 증가하였다. sample 7과 비교하면 sample 8은 효율이 12% 및 출력이 17.3% 증가되었다. This paper designed the main blade in V-shape and tried to identify the design conditions by changing the main blade number and sub-blade number. Power output and power coefficient increased as main blade number increased. Sample 2 shows a 50% increase in power output compared to sample1. Sample 3 and sample4 increased by 92.8% and 114.7%, respectively. Sample 2 shows a 38.4% increase in power coefficient compared to sample1. Sample 3 and sample4 increased by 92.3% and 107.7%, respectively. Power output and power coefficient increased as sub-blade number increased. Sample 6 shows a 33.3% increase in power output compared to sample 5 and Sample 7 increased by 42.1%. Compared to sample5, efficiency increased by 35.3% for sample 5 and 47.1% for sample 7. The highest power output and power coefficient were measured when main blade and sub-blade were each 30 number. Sample 8 increased power output by 5.6% and power efficiency by 3.7% compared to sample 4. Compared to sample 7, sample 8 increased power efficiency by 12% and power output by 17.3%.

비행시험 데이타를 이용한 전술용 미사일의 공력계수 추정

이달호(Dal-Ho Lee),이장규(Jang G. Lee) 한국항공우주학회 1985 韓國航空宇宙學會誌 Vol.13 No.3

RF Power 변화에 의한 CdS 박막 특성에 관한 연구

이달호(Dal-Ho Lee),박정철(Jung-Cheul Park) 한국정보전자통신기술학회 2021 한국정보전자통신기술학회논문지 Vol.14 No.2

본 논문은 ITO 유리를 기판으로 사용하여 CdS 박막을 제작하였다. MDS (Multiplex Deposition Sputter System)을 이용하여 RF power와 증착시간을 변화시키면서 소자를 제작하였다. 제작된 시편은 광학적 특성에 대해 분석을 하였다. 본 논문의 목적은 태양전지의 광흡수층에 적용될 수 있는 제작조건을 찾는 것이다. RF power가 50W이고 증착 시간이 10분 일 때, 두께는 64Å로 측정되었다. 100W일떄, 두께는 406Å로 측정되었고, 150W일 때는 두꼐는 889Å로 측정되었다. 박막은 RF power가 증가할수록 두께가 증가되는 것을 확인하였다. 광투과율 측정한 결과, 550~850nm는 RF power가 50W, 100W, 150W일 때 모두 투과율이 대략 70% 이상으로 관찰되었다. RF power가 증가되면 두께가 증가되고 입자 크기가 커지므로 박막의 밀도가 증가되어 광투과율이 감소되었다. RF power를 100W로 하고 증착시간을 15분 일 때, 밴드갭은 3.998eV로 계산되었다. 증착시간을 20분일 때, 3.987eV이고 150W는 15분에서는 3.965eV이며 20분에서는 3.831eV이다. RF power가 증가하면 밴드갭이 증가하는 것으로 측정되었다. XRD 분석에서 RF power와 증착시간의 변화에 관계없이 2Θ=26.44에서의 회절 피크를 관찰할 수가 있었다. 반치폭은 증착시간이 증가하면 감소되는 것을 알 수가 있었다. 그리고 RF power를 일정하게 하고 증착시간을 증가하면 입자크기는 증가되는 것으로 측정되었다. This paper produces CdS thin film using ITO glass as substrates. The MDS (Multiplex Deposition Sputter System) was used to produce devices by changing RF power and deposition time. The manufactured specimen was analyzed for its optical properties. The purpose of this paper is to find the fabrication conditions that can be applied to the photo-absorbing layer of solar cells. When RF power was 50W and deposition time was 10 minutes, the thickness was measured at 64Å. At 100W, the thickness was measured at 406Å and at 150 W, the thickness was measured at 889Å. Thin films were found to increase in thickness as RF power increased. As a result of the light transmittance measurement, 550–850nm was observed to have a transmittance of approximately 70% or more when the RF power was 50W, 100W, and 150W. Increasing RF power increased thickness and increased particle size, resulting in increased thin film density, resulting in reduced light transmittance. When RF power was 100W and deposition time was 15 minutes, the band gap was calculated at 3.998eV. When deposition time is 20 minutes, it is 3.987eV, 150W is 3.965eV at 15 minutes, and 3.831eV at 20 minutes. It was measured that the band gap decreased as the RF power increased. At XRD analysis, diffraction peaks at 2Θ=26.44 could be observed regardless of changes in RF power and deposition time. The FWHM was shown to decrease with increasing deposition time. And it was measured that the particle size increased as RF power was constant and deposition time was increased.

비선형 시스템의 계수추정 알고리즘 연구

李達鎬(Dal-Ho Lee),成相萬(Sang-Man Seong) 대한전기학회 1999 전기학회논문지A Vol.48 No.7

정보통신설비분야의 설계 · 감리 활성화 방안 연구

이달호(Dal Ho Lee),한형석(Hyung Seok Han),김형중(Hyung Joong Kim),최경(Kyung Choi) 대한전기학회 2004 대한전기학회 학술대회 논문집 Vol.2004 No.5