http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
기상 상태 변화에 따른 직육면체의 재질별 표면온도 변화 특성에 대한 실험 연구
김동건,최준혁,길태준,김정호,김태국,Kim, Dong-Geon,Choi, Jun-Hyuk,Kil, Tae-Jun,Kim, Jung-Ho,Kim, Tae-Kuk 한국군사과학기술학회 2012 한국군사과학기술학회지 Vol.15 No.2
The spectral radiance received by a remote sensor is consisted of the self-emitted component directly from the target surface, the reflected component of the solar irradiance at the target surface, and the scattered component by the atmosphere without ever reaching the object surface. In general, the self-emitted component is the most important part in the infrared signatures from the target. We measured the solar irradiation, sky irradiation, air temperature, wind velocity, wind direction, relative humidity, and atmospheric pressure together with the surface temperatures of rectangular parallelepiped targets. The measured diurnal surface temperature variations on the three different rectangular parallelepiped targets constructed by the steel, aluminum and bakelite are obtained at the same time intervals. The measured surface temperature results show that the top surface temperature of bakelite recorded up tp $7.6^{\circ}C$ higher than that of aluminium and $6.1^{\circ}C$ higher than that of steel at 11 AM on the sunny condition. A complete set of measured data including the surface temperature of rectangular parallelepiped targets together with the detailed weather information can be a valuable reference for future study.
위성용 전개형 고안정 반사판 안테나 복합재 주반사판 설계 및 해석
김동건,구경래,김현국,송성찬,권성철,임재혁,김영배,Dong-Geon Kim,Kyung-Rae Koo,Hyun-Guk Kim,Sung-Chan Song,Seong-Cheol Kwon,Jae-Hyuk Lim,Young-Bae Kim 한국복합재료학회 2023 Composites research Vol.36 No.3
The deployable reflector antenna consists of 24 unit main reflectors, and is mounted on a launch vehicle in a folded state. This satellite reaches the operating orbit and the antenna of satellite is deployed, and performs a mission. The deployable reflector antenna has the advantage of reduce the storage volume of payload of launch vehicle, allowing large space structures to be mounted in the limited storage space of the launch vehicle. In this paper, structural analysis was performed on the main reflector constituting the deployable reflector antenna, and through this, the initial conceptual design was performed. Lightweight composite main reflector was designed by applying a carbon fiber composite and honeycomb core. The laminate pattern and shape were selected as design variables and a design that satisfies the operation conditions was derived. Then, the performance of the lightweight composite reflector antenna was analyzed by performing detailed structural analysis on modal analysis, quasi-static, thermal gradient, and dynamic behavior.
아두이노를 이용한 위치정보 기반 안전한 자전거 애플리케이션
김동건,이호세,김소영,김태우,이형우,Kim, Dong-Gun,Lee, Ho-Se,Kim, So-Young,Kim, Tae-Woo,Lee, Hyung-Woo 한국사물인터넷학회 2016 한국사물인터넷학회 논문지 Vol.2 No.1
최근 자전거 이용자가 천만 명을 돌파하면서 자전거 라이딩은 일상생활의 요소로 자리 잡고 있다. 하지만, 이용자가 늘어날수록 사고의 위험에 무방비로 노출되면서 보다 안전하게 라이딩을 할 수 있는 예방 대책 수립이 절실하다. 이에 본 논문에서는 GPS 정보를 통하여 획득된 위치정보를 활용하여 사용자에게 주행 상황에 맞는 다양한 서비스를 제공할 수 있는 애플리케이션을 개발하였다. 이를 위해 안드로이드와 아두이노 기반 디바이스간 블루투스 송수신을 통해 자전거 전용 내비게이션 기능을 제공하여 안전성을 향상시킬 수 있었다. 향후 다양한 형태의 아두이노 센서로 확장할 경우 개인 맞춤형 모바일 IoT 서비스로 발전시킬 수 있을 것이라 기대한다. Bicycle users were surpassed a million recently as bicycle riding will be a key element of daily life. As users increase, we can expect that the user is more exposed to the risk of an unexpected accident. Therefore, we need to establish several preventive measures for a safe riding environment. In this paper, we developed mobile application by using the acquired GPS-based location information that provide safety services for the bike riding as a LBS service. In detail, we have been able to provide a bicycle safety navigation service by using the bluetooth transmission and reception method between Android and Arduino-based devices. As a future work, the safety could be improved if we expand various forms of Arduino sensors. As a result, a service developed in this study will be able to converge ahead to connect into several personalized mobile IoT services.
BRDF를 고려한 적외선 신호의 반사 성분 고속 연산기법에 관한 연구
김동건,한국일,최준혁,최순호,김태국,Kim, Dong-Geon,Han, Kuk-Il,Choi, Jun-Hyuk,Choi, Soon-Ho,Kim, Tae-Kuk 한국군사과학기술학회 2017 한국군사과학기술학회지 Vol.20 No.1
This paper is a part of developing a computer code that can be used to generate synthetic IR images by calculating the outgoing infrared signal from objects. To predict the reflected component that is a part of the outgoing IR signal, such as those components reflected from the target surface by the solar and sky irradiations, it is necessary to calculate the complicated BRDF values for considering the directional surface reflection characteristics. Since the calculation of reflectance using the BRDF requires a large amount of computation time due to the hemispherical integral term, it is frequently restricted in applying for a real-time prediction of IR signal. In this research, the simplified method for calculating IR reflected component has been proposed by replacing the integral terms into two parts, a directionally uniform component and a step function representing the specular component, to reduce computation time. The proposed method is proved to result in very fast calculation of the BRDF (up to 600 times faster calculations) for most of the surfaces with minimal loss of the accuracy.
초음파유화술과 후방인공수정체 삽입술을 시행한 성인에서 발생한 동공차단
김동건,정인영,Dong-Gun Kim,In-Young Chung 대한안과학회 2005 대한안과학회지 Vol.46 No.8
Purpose: To report on the pupillary block that rarely occurs after phacoemulsification with posterior chamber intraocular lens (IOL) implantation. Methods: A series of four eyes in four diabetic patients treated for pupillary block after uneventful phacoemulsification with posterior chamber IOL is described. Results: The interval between pupillary block development and the cataract surgery ranged from 1 week to 19 weeks. In all eyes, neodymium-YAG laser peripheral iridotomy relieved the block (-one procedure in three patients; and two procedures in one-). Conclusions: Despite the rarity of the complication of pupillary block after phacoemulsification with posterior chamber IOL, physicians should require closer follow-up is necessary, especially in diabetic patients.
PIV기법을 이용한 병렬 평면제트의 유동특성 (I) - 유입이 제한된 제트 -
김동건,윤순현,Kim, Dong-Keon,Yoon, Soon-Hyun 대한기계학회 2003 大韓機械學會論文集B Vol.27 No.3
Experiments were conducted to show the characteristics of the flow on unventilated parallel plane jets. Measurements of mean velocity components and turbulent intensities were carried out with a particle image velocimetry to investigate the flow field generated by the air issued from two identical plane parallel nozzles and mixed with the ambient air. The measurements range of these experiments were Reynolds number of 5300 based on the nozzle width and the cases of nozzle-to-nozzle distance were four times. six times and eight times the width of the nozzle. Results show that a recirculation zone with a sub-atmospheric static pressure was bounded by the inner shear layers of the individual jets and the nozzles plate. The positions. where maximum value of mean turbulent intensities and mean turbulent kinetic energy show, were at the same position with the merging point. The spread of jets in the merging region increases more rapidly than that of Jets in the converging and the combined region. As nozzle-to-nozzle distances were increased. it was shown that merging and combined lengths were shorter.