http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
오대근,김길원,김경문,피터 아콩테,김주경,이창훈,박보선,김수배,조유영,최용수,김동원 한국양봉학회 2023 韓國養蜂學會誌 Vol.38 No.1
Honeybees are an important species influencing many aspects of human life, particularly economic and agriculture. Plant production depends upon pollination, and this is mainly enabled by honebees. Beekeepers across the Korea are experiencing unprecedented drops and losses in honeybee colonies. These losses have been attributed to bee mites (Varroa destructor and Tropilaelaps mercedesae) infestation. Application of acaricides is the most common practice to control bee mites. Among acaricides, formic acid is quite popular in Varroa mites control due to a natural substance with low residue levels in honey. However, beekeepers cannot use it without proper knowledge because it can cause significant harm to honeybees if used incorrectly. Therefore, this study was conducted to investigate how the vaporization rate of formic acid changes depending on the season in Korea.
노즐내 이차원 물체에 의한 피동제어된 아음속 제트구조에 관한 연구
오대근,윤복현,김태호 국립7개대학공동논문집간행위원회 2003 공업기술연구 Vol.3 No.-
A turbulent wake generated by a cylinder in nozzle contraction affects to the jet flow characteristics. In this study, a computational work to investigate the effect of the turbulent wake on two-dimensional subsonic jet was carried out with three different kinds of nozzle. Computations are applied to the two-dimensional unsteady, Navier-Stokes equations. Several kinds of turbulent models and wall functions are employed to validate the computational predictions. It was known that the wake flow enhanced the spread of the jet flow, compared with no wake flow condition. It was also found that the jet core is shortened by the wake flow developed from a control cylinder.
실린더 후류를 이용한 아음속 디퓨저 유동의 제어에 관한 연구
오대근,윤복현,김태호 국립7개대학공동논문집간행위원회 2005 공업기술연구 Vol.5 No.-
The present study addressed a computational work to investigate the influence of a turbulent wake flow on the pressure recovery of subsonic diffuser. The turbulent wake is generated by a cylinder with a small diameter, which is installed at the diffuser inlet of a 2-dimensional diffuser Computation are applied to three-dimensional steady Navier-Stokes equations. The computational results are qualitatively well compared to existing experimental results. The results show that the diffuser pressure recovery of the subsonic diffuser is dependent on the diameter and location of the cylinder. It is found that a certain diameter and location of cylinder to generate the turbulent wake give a better pressure recovery, compared with no cylinder flow
노즐내 물체의 후류가 아음속 이차원 제트구조에 미치는 영향에 관한 수치해석적 연구
오대근,윤복현,김태호 국립7개대학공동논문집간행위원회 2004 공업기술연구 Vol.4 No.-
A turbulent wake generated by a cylinder in nozzle contraction affects to the jet flow characteristics. In this study, a computational work to investigate the effect of the turbulent wake on two-dimensional subsonic jet was carried out with three different kinds of nozzle. computations are applied to the two-dimensional unsteady, Navier-Stokes equations. Several kinds of turbulent models and wall functions are employed to validate the computational predictions. It was known that the wake flow enhanced the spread of the jet flow, compared with no wake flow condition. It was also found that the jet core is shortened by the wake flow developed from a control cylinder.
지면효과익을 지나는 가/감속 유동의 공력특성에 관한 수치해석적 연구
오대근,윤복현,김태호 국립7개대학공동논문집간행위원회 2005 공업기술연구 Vol.5 No.-
Recently, several kinds of experimental and computational studies are being carried out to investigate the WIG(Wing In Ground Effect) aerodynamic characteristics which are of practical importance to develop the new ground transportation vehicle system. These works are mainly based upon conventional wind tunnel tests, but many problems associated with the WIG aerodynamic characteristics cannot be satisfactorily resolved due to the wind tunnel blockage effects or string problems to support the test object. To overcome the problems, it is necessary to develop a novel simulator appropriate to the WIG aerodynamics. The lift increased in accelerating and decelerating flows without the Reynolds number, and the increase degree appeared remarkably as an dimensionless acceleration coefficient increased.
실린더 후류를 이용한 2차원 디퓨저 성능개선에 관한 수치해석적 연구
오대근,윤복현,김태호 국립7개대학공동논문집간행위원회 2004 공업기술연구 Vol.4 No.-
The present study addresses a computational work to investigate the influence of a turbulent wake flow on the pressure recovery of a two-dimensional subsonic diffuser. The turbulent wake is generated by a cylinder with a small diameter, which is installed at the diffuser inlet. Computation is applied to two-dimensional steady Navier-Stokes equations. The computational results are qualitatively well compared to existing experimental data. The results show that the diffuser pressure recovery is strongly dependent on the diameter and location of the cylinder. It is found that there is a certain diameter and location of cylinder for the diffuser pressure recovery to be most enhanced. Compared with no cylinder case, the diffuser performance increases up 24.
성숙기간과 후숙기간을 달리한 대목용 박(Lagenaria siceraria Standl.) 종자의 발아율
오대근,우영회,전진우,Oh, D.G.,Woo, Y.H.,Chun, J.W. 국립한국농수산대학교 교육개발센터 2018 현장농업연구지 = Journal of practical agricultural resear Vol.20 No.2
This study was conducted to elucidate the effect of after-ripening of gourd fruits before seed collection. Five varieties of commercial gourd varieties were cultivated and the fruits were picked after 24, 31, 50, and 70 days from pollination. For after-ripening treatments the fruits were placed for five days in a cool, air-circulated place while a number of fruits were placed for longer periods to 85 days including growing period, 24 + 62 days, 31 + 55 days, 50 + 35 days, and 70 + 15 days. The seeds collected from fruits harvested on 24<sup>th</sup> day were not emerged at all, but the seeds from after-ripening treatment for 62 days showed 78% emergence or higher. The growth of seedlings showed the effects of after-ripening treatment of the fruits before seed collection; the seeds collected after ripening treatment showed better hypocotyl growth and larger embryo size than the non-treated seeds.