http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Howon Lee,Jong Kwon Lee,Ung Gi Hong,Yeonshick Yoo,Young-Jin Cho,Jinsuk Lee,Ho-Sik Jang,정지철,송인규 한국공업화학회 2012 Journal of Industrial and Engineering Chemistry Vol.18 No.2
Vanadium-magnesium oxide (Mg3(VO4)2) catalysts supported on Al2O3, ZrO2, MgO, and CeO2 were prepared by a wet impregnation method, and they were applied to the oxidative dehydrogenation of nbutane. Effect of oxygen capacity and oxygen mobility of supported Mg3(VO4)2 catalysts on the catalytic performance in the oxidative dehydrogenation of n-butane was investigated. Experimental results revealed that large oxygen capacity of the catalyst was favorable for obtaining high catalytic activity at the initial stage of reaction, while facile oxygen mobility of the catalyst led to stable catalytic activity during the catalytic reaction in the oxidative dehydrogenation of n-butane.
멀티셀 A2G 통신 시뮬레이터 기반 접속 지연 제한에 따른 랜덤 접속 프로토콜 성능 분석
이준승(Lee Jun Seoung),이예린(Lee Ye Lin),이승민(Seungmin Lee),이호원(Howon Lee) 한국통신학회 2021 한국통신학회 학술대회논문집 Vol.2021 No.6
최근 다중 UAV(unmanned aerial vehicle) 네트워크에서 효율적인 데이터 송수신을 위한 랜덤 접속 프로토콜에 대한 연구 개발이 활발히 진행되고 있다. UAV들이 각자의 서비스에 따라 임무를 수행하는 경우, 각각의 UAV들은 지상제어국과 효율적으로 패킷을 송수신할 수 있어야 한다. 따라서, 본 논문에서는 멀티셀 A2G(air-to-ground) 통신 시뮬레이터를 기반으로 다중 UAV 무선 네트워크에서 효율적인 패킷 송수신을 위한 다양한 랜덤 접속 프로토콜들을 소개하고, 매트랩 시뮬레이션을 통해 접속 지연 제한에 따른 랜덤접속 프로토콜들의 성능을 비교 분석해본다.
커넥티드 UAVs의 수평 거리 분포에 따른 캡처 효과 성능 분석
이예린(Yelin Lee),임수현(Suhyeon Lim),이승민(Seungmin Lee),이준승(Junseoung Lee),이호원(Howon Lee) 한국통신학회 2022 한국통신학회 학술대회논문집 Vol.2022 No.2
최근 무선통신 분야에서 UAV(unmanned aerial vehicle) 관련 연구가 매우 활발히 진행되고 있다. 이에 따라 3차원 공간에서 네트워크 성능 향상을 위한 무선 자원의 효율적인 사용은 매우 중요하다. 따라서 본 논문에서는 무선 통신 환경에서의 캡처효과(capture effect)를 이용하여 채널 사용률을 향상시키기 위하여, 커넥티드-UAVs의 수평 거리 분포에 따른 랜덤 접속 프로토콜 별 캡처효과 성능을 비교 분석한다.
Howon Lee,정지철,Heesoo Kim,정영민,Tae Jin Kim,Seung-Hoon Oh,Yong Seung Kim,Seong Jun Lee,송인규 한국화학공학회 2009 Korean Journal of Chemical Engineering Vol.26 No.4
Oxidative dehydrogenation of n-butene to 1,3-butadiene over ZnFe2O4 catalyst mixed with CsxH3−xPW12O40 heteropolyacid (HPA) was performed in a continuous flow fixed-bed reactor. The effect of CsxH3−xPW12O40 addition on the catalytic performance of ZnFe2O4 was investigated. CsxH3−xPW12O40 itself showed very low catalytic performance in the oxidative dehydrogenation of n-butene. However, addition of small amount of CsxH3−xPW12O40 into ZnFe2O4 enhanced the catalytic performance of ZnFe2O4 catalyst. The catalytic performance of ZnFe2O4-CsxH3−xPW12O40 mixed catalysts was closely related to the surface acidity of CsxH3−xPW12O40. Among the catalysts tested, ZnFe2O4-Cs2.5H0.5 PW12O40 mixed catalyst showed the best catalytic performance. Strong acid strength and large surface acidity of Cs2.5 H0.5PW12O40 was responsible for high catalytic performance of ZnFe2O4-Cs2.5H0.5PW12O40 mixed catalyst. Thus, Cs2.5 H0.5PW12O40 could be utilized as an efficient promoter and diluent in formulating ZnFe2O4 catalyst for the oxidative dehydrogenation of n-butene.
Scenario Test System for Performance Evaluation of the Cooperative Driving Functions
Howon Lee,Seok-Cheol Kee 제어로봇시스템학회 2019 제어로봇시스템학회 국제학술대회 논문집 Vol.2019 No.10
In this paper, a scenario test system is presented to verify wide area driving environment awareness and cooperative driving technology which are based on V2X wireless communication. The system was configured with sensors for driving environment in each vehicle and V2X modules for communication between vehicles. And V2X safety application based scenario test was conducted by proving ground for system verification.
Lee, Kisong,Lee, Howon,Jang, Yong-Up,Cho, Dong-Ho IEEE 2013 IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS Vol.12 No.11
<P>For the purpose of automating network management, self-organizing network (SON) technology is currently being investigated. There are three important issues in SON: self-configuration, self-optimization, and self-healing. This paper focuses on self-healing, in order to resolve the problem of unexpected network faults and improve network throughput simultaneously. To deal with this problem, we propose a healing channel selection and a cooperative beamforming-based iterative resource allocation algorithms. We utilize the cooperative beamforming in the healing channel based on phase pre-adjustment, and this cooperative beamforming can be performed without power cooperation between distributed nodes. Moreover, we derive the sub-optimality and convergence of the proposed algorithm in weak interference condition by using contraction mapping. Finally, simulation results demonstrate that the proposed algorithm improves average cell capacity and user fairness while repairing network failure effectively.</P>
Lee, Seunghyeon,Lee, Jaemin,Hwang, Hayoung,Yeo, Taehan,Lee, Howon,Choi, Wonjoon Elsevier 2018 Carbon Vol.140 No.-
<P><B>Abstract</B></P> <P>Biporous structures at the nano–microscale are promising candidates for controlling phase change heat transfer, through their enhanced capillary wicking and fluid transportation. However, existing methods for fabricating biporous structures involve complex process which is not suitable for small-scale thermal devices such as heat pipes, owing to their confined and non-flat inner structures. Herein, we report the biporous structures inside copper-sintered heat pipes, enabled by layer-by-layer (LbL) assembled multi-walled carbon nanotube (MWCNT)-polyethyleneimine (PEI) coating for enhanced thermal performance. The repetitive filling and removing of the oppositely charged solutions with MWCNT-PEI and carboxylic-functionalized MWCNTs assembled the nanoporous MWCNT-PEI coatings (10, 20, and 40 bilayers) on the microporous copper-sintered inner surfaces. The fiber-like MWCNT networks structurally manipulated morphology and thickness of biporous structures, while the hydrophilic PEI shells chemically optimized wettability. A reduced thermal resistance (∼14.3%) was observed for MWCNT-PEI coating in 10 bilayers, due to the enhanced capillary wicking, interfacial contact areas, and bubble dynamics, whereas the 40 bilayers did not exhibit improved thermal performance owing to the redundant nanoporous layers causing reduced volume of microporous structures and increased thermal resistance. The LbL-assembled MWCNT-PEI coatings would act as functional layers to improve the performance of miniaturized and thin-film-based thermal devices.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>