http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
오늘 본 자료
Lim, Guh-Hwan,Woo, Seongwon,Lee, Hoyoung,Moon, Kyoung-Seok,Sohn, Hiesang,Lee, Sang-Eui,Lim, Byungkwon American Chemical Society 2017 ACS APPLIED MATERIALS & INTERFACES Vol.9 No.46
<P>The introduction of inorganic nanoparticles into carbon nanotube (CNT) papers can provide a versatile route to the fabrication of CNT papers with diverse functionalities, but it may lead to a reduction in their mechanical properties. Here, we describe a simple and effective strategy for the fabrication of mechanically robust magnetic CNT papers for electromagnetic interference (EMI) shielding and magnetomechanical actuation applications. The magnetic CNT papers were produced by vacuum filtration of an aqueous suspension of CNTs, CoFe2O4 nanoparticles, and poly(vinyl alcohol) (PVA). PVA plays a critical role in enhancing the mechanical strength of CNT papers. The magnetic CNT papers containing 73 wt % of CoFe2O4 nanoparticles exhibited high mechanical properties with Young's modulus of 3.2 GPa and tensile strength of 30.0 MPa. This magnetic CNT paper was successfully demonstrated as EMI shielding paper with shielding effectiveness of similar to 30 dB (99.9%) in 0.5-1.0 GHz, and also as a magnetomechanical actuator in an audible frequency range from 200 to 20 000 Hz.</P>
Fuzzy Power Factor Control Systems
Seongwon Cho,Jaemin Kim,Jaeyoon Jung,Cheolsu Lim 한국지능시스템학회 2004 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.4 No.1
A method for obtaining the power energy with high quality is to keep the power factor for a load as close to unity as feasible. In this paper, we present a new method to improve the power factor for a load. The proposed method uses fuzzy control techniques in order to determine how many parallel capacitors are to be connected to the load for the correction of the power factor.
LPG 연료 조성비에 따른 LPLi엔진의 개별탄화수소 배출특성 및 연소현상에 대한 연구
최성원(Seongwon Choi),임무창(Muchang Lim),곽호철(Hochul Kwak),명차리(Cha-Lee Myung),박심수(Simsoo Park) 한국자동차공학회 2006 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-
The regulation for hydrocarbon emissions from vehicles have become much more stringent in recent years. These more stringent regulations request vehicle manufacturers to develop the exhaust system for reducing exhaust emissions. The exhaust emission has many sources in vehicle. In order to investigate the hydrocarbon(HC) in the exhaust port, concentrations of individual HC species were measured in exhaust process. using sampling valve, the light hydrocarbon emissions were captured in the exhaust port(catalyst before and after)and analyzed from LPLi engine exhaust port(catalyst before and after) by using different fuel properties. Then exhaust samples were measured by gas chromatography(GC) and exhaust gas analyzer. Catalyst conversion efficiency for different fuel properties of Butane 100% was better than Propane 100%.
H.264/AVC에서 변환계수의 부분집합을 사용한 인트라 16×16 예측 모드 선택 방법
임상희(Sanghee Lim),이성원(Seongwon Lee),백준기(Joonki Paik) 대한전자공학회 2007 電子工學會論文誌-SP (Signal processing) Vol.44 No.6
본 논문에서는 기존의 고속 인트라 4×4 예측 모드 선택 알고리즘을 인트라 16×16 예측에 적용하여 연산량을 감소시키고, 변환 계수의 일부분만을 사용하여 인트라 16×16 예측 모드 선택을 고속으로 수행하는 방법을 제안한다. 제안하는 방법은 기준 블록과 예측 블록간의 차분에 4×4 변환을 수행한 후 DC계수 하나와 주변의 AC계수 3개만을 사용하여 모드 선택을 수행한다. 이론적인 분석과 실험적 결과를 통해서 제안한 방법을 사용하여 인트라 16×16 예측 모드 선택을 수행할 경우 부호화 효율의 큰 감소 없이 필요한 연산량을 50%까지 줄일 수 있었다. In this paper, we significantly reduces the amount of computation for intra 16×16 mode decision in H.264 by applying the fast algorithm, which obtains the transformed prediction residual with fewer computations. By extending the existing intra 4×4 mode decision, we propose the new algorithm for fast intra 16×16 mode decision. The proposed algorithm uses partial transform coefficients which consist of one DC and three adjacent AC coefficients after 4×4 transform in the intra 16×16 mode decision. Theoretical analysis and experimental results show that the proposed algorithm can reduce computations up to 50% in the intra 16×16 mode decision process with unnoticeable degradation.
Seismic Retrofitting of RC Circular Columns Using Carbon Fiber, Glass Fiber, or Ductile PET Fiber
Donguk Choi,Seongwon Hong,Myung-Kwan Lim,Sang-Su Ha,Sorrasak Vachirapanyakun 한국콘크리트학회 2021 International Journal of Concrete Structures and M Vol.15 No.6
The effectiveness of seismic retrofitting using three different fibers-carbon fiber (CF), glass fiber (GF), polyethylene terephthalate (PET) fiber-and a fiber combination of aramid fiber (AF) and PET fiber (called hybrid fiber reinforced polymer (HF)) wrapped on reinforced concrete (RC) circular columns was experimentally evaluated. A total of 11 RC circular columns were tested: three control columns and eight retrofitted columns in three different test groups. The purpose of fiber wrapping was flexural strength improvement as well as enhancement of rotational capacity in the plastic hinge region. Mechanical properties of CF, GF, AF, and PET were first defined; that is, CF, GF, and AF exhibited linear stress-strain behavior with limited ultimate strain capacity typically less than 3%, while ductile PET exhibited as much as 15% strain and non-linear stress-strain behavior with a very low elastic modulus. In the RC column tests, all three different fibers and the AF + PET fiber combination were effective in enhancing the strength and ductility but resulted in different structural behaviors and failure modes depending on the fiber type and the fiber amount used. The column sections were then analytically studied by section analysis using the behavior of confined concrete, the non-linear relationship of fiber-reinforced polymer (FRP), and the actual material properties of reinforcement. The analytical and experimental results revealed that ductile PET is beneficial, as it demonstrates more ductile behavior with a degree of strength enhancement similar to that of CF and GF.
임용배(Young Bae Lim),김동우(Dong Woo Kim),진상민(Sangmin Jin),조성원(Seongwon Cho) 한국지능시스템학회 2016 한국지능시스템학회논문지 Vol.26 No.5
최근 사물인터넷 기반의 재해예방 기술이 개발되고 있다. 본 논문에서는 사물인터넷기반의 공동주택용 자율전기안전관리기술 개발을 위하여 부하 전류 파형을 FFT와 MFCC를 이용하여 신호변환 후 신경회로망 모델에 적용하여 정확도가 개선된 전기 부하 패턴분류 시스템을 제안한다. 오실로스코프와 CT를 이용하여 측정한 전기 부하의 전류 파형을 FFT 알고리즘을 적용한 후 신경회로망을 이용하여 단일부하패턴 분류 실험을 하였다. 본 연구를 통하여 부하의 특성을 파악함으로서 고장에 대해 보다 신속하고 정확하게 대처할 수 있을 것으로 예측된다. Recently several techniques for disaster prevention based on IoT(Internet of Things) are being developed. In this paper, a new smart pattern classification method for electric loads is proposed. CT(Current Transformer) data are extracted from electric loads, and then the sampled CT data are converted using FFT and MFCC. FFT and FMCC data are used for the input data of neural networks. Experiments were conducted using FFT and MFCC data for 7 kinds of electric loads. Experiments results indicate the superiority of MFCC in comparison to FFT.