층층나무 잎의 Phenol성 성분 (I)

이동호,이승호,정시련,노재섭,이경순,Lee, Dong-Ho,Lee, Seung-Ho,Chung, See-Ryun,Ro, Jai-Seup,Lee, Kyong-Soon 한국생약학회 1995 생약학회지 Vol.26 No.4

Twelve phenolic components were isolated from the aqueous acetone extract of the leaf of Cornus controversa H. (Cornaceae). On the basis of chemical and spectroscopic evidence, the structures of these components were established as gallic acid, $1-O-galloyl-{\beta}-{_D}-glucose$, $1,6-di-O-galloyl-{\beta}-{_D}-glucose$, $1,2,3-tri-O-galloyl-{\beta}-{_D}-glucose$, $1,2,6-tri-O-galloyl-{\beta}-{_D}-glucose$, 3,4,6-tri-O-galloyl ${_D}-glucose$, eugeniin, gemine D, quercetin, quercitrin, hyperoside and rutin.

초소형 수중 음향 시스템 모듈의 저잡음 설계 방법

이동호,신영산,송진호,위재경,이정민,설재수,Lee, Dong-Ho,Shin, Young-San,Song, Jin-Ho,Wee, Jae-Kyung,Lee, Jeong-Min,Seol, Jae-Soo 한국음향학회 2012 韓國音響學會誌 Vol.31 No.5

본 논문에서는 다중 전압을 사용하는 초소형 시스템 구성 및 모듈 설계 방법론을 제시한다. 특히 잡음에 취약한 아날로그 IC의 특성을 개선하기 위한 PDN 구성 방법과 필터 구성 방법에 중점을 두어 설계하였다. 이에 제작된 모듈은 고전압에 의한 잡음을 방지하기 위해 공급 전원별로 접지면을 분할하고, 이를 공통 접지면으로 구성하기 위해 필터를 연결하였으며, via stitching 기법을 사용하였다. 이를 본 논문에서는 PDN 구조를 Lumped 모델로 구성하여 시뮬레이션을 통해 분석하고, 측정을 통해 확인하였다. 시뮬레이션 결과 4.7 uH의 Inductor를 연결하였을 때, 공통 접지면을 사용했을 때보다 -7 dB의 잡음 감소 효과를 확인할 수 있었고, 측정 결과 약 12 %가 감소하였음을 확인할 수 있었다. This paper suggest configuration method of small-size system and design method of module using multi power. In particular module designed to focus on PDN(Power Distribution Network) and filter configuration method to improve the characteristics of noise sensitive analog IC. For the prevention of high-voltage noise, manufactured module is used the ground-isolated technique and via stitching, and is connected grounds with a series of filters. In this paper, so we analyzed PDN structure through the simulation using lumped modeling and confirmed through measurement. Simulation results, when connecting 4.7uH inductor, we made certain that noise of -7dB decreases much more than when it did not. And it was confirmed 12% less than Background Noise.

분산제가 BaTiO₃/에폭시 복합체의 유전특성에 미치는 영향

이동호,김병국,제해준,Lee, Dong-Ho,Kim, Byung-Kook,Je, Hae-June 한국재료학회 2009 한국재료학회지 Vol.19 No.11

$BaTiO_3$/epoxy composites have been widely investigated as promising materials for embedded capacitors in printed circuit boards. It is generally known that the dielectric constant (K) of the $BaTiO_3$/epoxy composites increases with improvement of the dispersion of $BaTiO_3$ particles in the epoxy matrix that comes from adding surfactant. The influences of surfactant addition on the dielectric properties of the $BaTiO_3$/epoxy composites are reported in the present study. The dielectric constant of the $BaTiO_3$/epoxy composites is not significantly affected by the surfactant addition. However, the temperature coefficient of capacitance increases and the peel strength decreases as the amount of added surfactant increases. The influences of surfactant addition on the dielectric properties of the neat epoxy are also very similar to those of the $BaTiO_3$/epoxy composites. The residual surfactant in the $BaTiO_3$/epoxy composites affects the temperature coefficient of capacitance and the peel strength of the epoxy matrix, which in turn affects the temperature coefficient of capacitance and the peel strength of the $BaTiO_3$/epoxy composites.

Polymerization of Ethylene Initiated with Polymethylene - bridged Dinuclear Zirconocene Catalysts

이동호,이헌봉,윤근병,노석균 ( Dong Ho Lee,Hun Bong Lee,Keun Byung Yoon,Seok Kyun Noh ) 한국공업화학회 1997 한국공업화학회 연구논문 초록집 Vol.1994 No.1

무선 내장형 시스템을 위한 제비용 AES의 구현

이동호,LEE Dong-Ho 대한전자공학회 2004 電子工學會論文誌-SD (Semiconductor and devices) Vol.41 No.12

AES is frequently used as a symmetric cryptography algorithm for the Internet. Wireless embedded systems increasingly use more conventional wired network protocols. Hence, it is important to have low-cost implementations of AES for thor The basic architecture of AES unrolls oかy one full cipher round which uses 20 S-boxes together with the key scheduler and the algorithm repeatedly executes it. To reduce the implementation cost further, the folded architecture which uses only eight S-box units was studied in the recent years. In this paper, we will study a low-cost AES implementation for wireless communication technology based on the folded architecture. We first improve the folded architecture to avoid the sixteen bytes of additional state memory. Then, we implemented a single byte architecture where only one S-box unit is used for data encryption and key scheduling. It takes 352 clocks to finish a complete encryption. We found that the maximum clock frequency of its FPGA implementation reaches about 40 MHz. It can achieve about 13 Mbps which is enough for 3G wireless communication technology. AES는 인터넷 프로토콜의 대칭키 보안 알고리즘으로 널리 사용된다. 무선 내장형 시스템들이 점점 더 전통적인 유선 네트워크 프로토콜을 많이 사용하고 있으므로 이들 무선 내장형 시스템을 위한 저비용 AES 알고리즘 구현은 매우 중요하다. 가장 기본적인 AES 아키텍처는 키 스케줄을 포함하여 20개의 S-box를 사용하는 하나의 cipher 라운드로 구성되어 있다. 암호화는 동일한 라운드를 반복하여 완료된다. 근래에 이 방법의 구현 비용을 더욱 줄이기 위하여 오직 8개의 S-box만 사용하는 folded architecture가 제안되었다. 본 논문에서는 folded architecture를 이용하여 무선 통신 기술을 위한 저비용 AES 구현 구조에 대하여 연구한다. 먼저 folded architecture를 개선하여 16 바이트의 추가적인 상태 메모리 사용을 줄였다. 구현 비용을 더욱 줄이기 위하여 데이터 암호화에 하나의 S-box만 사용하는 single byte architecture를 구현하였다. Single byte architecture는 암호화에 352 클록이 소요된다. FPGA 구현 시 최대 동작 주파수는 40MHz에 도달하였다. 따라서 암호화 속도는 13Mbps 이상으로 3G 무선통신에 충분하다.

Polymerization of ethylene having bimodal molecular weight distribution with mixture of polysiloxane - bridged mono - and dinuclear zirconocenes

이동호,윤근병,노석균,김수찬 ( Dong Ho Lee,Keun Byoung Yoon,Seok Kyun Noh,Soo Chan Kim ) 한국공업화학회 1996 한국공업화학회 연구논문 초록집 Vol.1990 No.3

압전작동기로 구동 되는 보울 파트 피더의 모드 해석과 이송 속도 제어

이동호,최승복,김재환,Lee, Dong-Ho,Choe, Seung-Bok,Kim, Jae-Hwan 대한기계학회 2000 大韓機械學會論文集A Vol.24 No.4

This paper presents modal analysis and mean conveying velocity (M.C.V.) control of bowl parts feeder activated by piezoactuators. Bowl parts feeders are being widely used in many industry fields for automatic assembly line. In general, the electromagnet has been and being used as exciting actuator of these vibratory bowl feeders. However, because of complexity of its mechanism and limited capability of the electromagnet actuator, there exist various impending problems such as severe noise, nonlinear motion of parts, passive characteristics and so forth. As one of solutions for these problems, piezoelectric actuators as new actuating technology have been proposed recently to excite the bowl parts feeder. In this paper, modal analysis of the proposed model has been performed to examine the modal characteristics of the model by using commercial FEM software and modeling with respects to MCV is constructed. Finally, MCV of the parts is to be controlled to track the desired one with PID controller.

터널 내 화재 시 경사에 따른 온도층 및 연기유동 특성

이동호,김하영,문성웅,유지오,Rie, Dong-Ho,Kim, Ha-Young,Moon, Sung-Woong,Yoo, Ji-Oh 한국터널지하공간학회 2009 한국터널지하공간학회논문집 Vol.11 No.3

본 연구는 터널 내 화재 시 온도층 및 연기층의 유동성향을 분석한다. 이를 위해 전산 시뮬레이션을 활용하였다. NIST의 FDS를 통해 국도 및 고속도로 표준단면을 기준으로 화재 시나리오를 설정하였다. 연기층의 이동거리는 터널의 단면적이 증가할수록 내부 풍속에 의한 영향력이 감소하였으며, 내부 풍속이 상승할수록 경사에 의한 영향력이 감소하였다. 온도층의 이동거리는 내부풍속이 상승할수록 경사에 의한 영향력이 감소하였으며, 1 m/s 이상의 풍속에 냉각효과가 나타나 경사에 의한 영향력이 감소하였다 The aim of this research is to analyse the dynamic characteristics of the hot upper smoke layer in case of fire in a tunnel. In order to get the result, computer simulation technique has been used. The fire scenarios were set on the basis of standard cross section of national and express highways through NIST's FDS. As the area of a tunnel increased, the influence of the wind velocity decreased. Furthermore, the influence of the slope of a road was reduced as the wind velocity increased. On the other hand, as the wind velocity increased, the influence of the slope of a road decreased. This phenomena is believed to be caused by the cooling effect of wind which is over 1 m/s in speed, hence, reducing the influence of the effect of slope.

이층 기판용 3 dB 커플러

이동호,Lee, Dong-Ho 한국전기전자학회 2014 전기전자학회논문지 Vol.18 No.4

가장 많이 쓰이는 FR4 이층 기판을 사용하여 3 dB 커플러를 설계하고 제작하였다. 커플러 일부의 겹치는 면적을 키워서 커플링을 증가시키고 대역폭을 증가시키는 구조를 제안하였다. 설계를 위한 주요 파라미터 값들을 여러 조건에 따라 도시하였고, 시뮬레이션과 측정을 통해 검증하였다. 제작된 커플러의 크기는 $30{\times}14mm^2$이고, 중심 주파수 2.5 GHz 에서 0.6 dB의 삽입 손실과 $90.5^{\circ}$의 위상차를 측정으로부터 얻었다. 측정된 삽입 손실 $3.6{\pm}0.5dB$에 대한 주파수 범위는 1.72 GHz에서 3.08 GHz이다. 제안한 커플러는 기존의 랭 커플러와 유사한 성능을 보였고, 와이어 본딩 공정이 필요 없어 추가 비용이 들지 않고 도선의 폭과 간격이 넓어서 제작이 용이하다. A 3 dB coupler has been designed and implemented using the most commonly used double-sided FR4 boards. The coupling and the bandwidth of the coupler are enhanced with the enlarged overlapped area of the coupler. Major design parameters are plotted as a design guide and the parameters are verified by simulation and measurement. The size of the manufactured coupler is $30{\times}14mm^2$. Its measured insertion loss and phase difference are 0.6 dB and $90.5^{\circ}$ at center frequency of 2.5 GHz, respectively. The operating frequency range is 1.72 GHz to 3.08 GHz for $3.6{\pm}0.5dB$ insertion loss. The coupler has the performance similar to that of conventional Lange coupler, and implementation of the coupler is easy and cheap with wide metal width and spacing and no additional wire bonding process.

환형 캐스케이드 내 고정된 터빈 블레이드 및 슈라우드에서의 열/물질전달 특성 (II) - 끝단 필 슈라우드 -

이동호,조형희,Lee Dong-Ho,Cho Hyung Hee 대한기계학회 2005 大韓機械學會論文集B Vol.29 No.4

Experiments were conducted in a low speed stationary annular cascade to investigate local heat transfer characteristics on the tip and shroud and the effect of inlet Reynolds number on the tip and shroud heat transfer. Detailed mass transfer coefficients on the blade tip and the shroud were obtained using a naphthalene sublimation technique. The turbine test section has a single stage composed of sixteen guide vanes and blades. The chord length and the height of the tested blade are 150 mm and about 125 mm, respectively. The blade has flat tip geometry and the mean tip clearance is about $2.5{\%}$of the blade chord. The inlet flow Reynolds number based on chord length and incoming flow velocity is changed from $1.0{\times}10^{5}\;to\;2.3{\times}10^{5}.$ to investigate the effect of Reynolds number. Flow reattachment after the recirculation near the pressure side edge dominates the heat transfer on the tip surface. Shroud surface has very intricate heat/mass transfer distributions due to complex flow patterns such as acceleration, relaminarization, transition to turbulent flow and tip leakage vortex. Heat/mass transfer coefficient on the blade tip is about 1.7 times as high as that on the shroud or blade surface. Overall averaged heat/mass transfer coefficients on the tip and shroud are proportional to $Re_{c}^{0.65}\;and\;Re_{c}^{0.71},$ respectively.