선형성을 개선한 저전압 CMOS RF 주파수 변환기 설계

고희곤,김영석 충북대학교 컴퓨터정보통신 연구소 2003 컴퓨터정보통신연구 Vol.11 No.2

본 논문은 선형성을 개선한 900MHz 저전압 CMOS 하향 주파수변환기를 제안하였고 회로 모의실험에 의하여 확인 하였다. 선형성 개선을 위하여 Class AB 트랜스컨덕터단을 사용하였고, RF 단과 LO 스위칭단을 캐패시터로 커플링시켜 저전압으로 동작 하게하였다. 1.0 GHz의 LO 신호를 가지고 3.0 V에서 동작하는 제안된 주파수 변환기는 회로 모의실험을 하여 선형성을 나타내는 ⅡP3는 4.8dBm, 변환이득은 0.6dB를 얻었다. 제안된 주파수 변환기는 길버트 주파수 변환기와 비교하여 선형성과 변환이득에서 개선됨을 보았다. 설계한 주파수 변환기는 RF 송수신기 시스템 등에서 활용될 것으로 기대된다. In this paper, the 900MHz low-voltage CMOS downconversion mixer with high linearity has been proposed and confirmed by circuit simulations. The class AB transconductor stage is used for high-linearity and capacitively coupled with LO switching stage for low-voltage applications. Circuit simulations show that the proposed mixer operating at 3.0V with 1.0GHz LO signal has ⅡP3 of 4.8dBm and conversion gain of 0.6dB. The linearity and conversion gain of the proposed mixer is much improved compared to that of the conventional Gilbert mixer. The proposed mixer with CMOS technology is used to be integrated into the one-chip RF transceiver system.

대뇌 발생 중 단백질과 ATP에 미치는 수은의 영향(1)

김생곤,고영무 대한치과기재학회 2001 대한치과재료학회지 Vol.28 No.3

The effect of HgCl2 on the differentiation of chicken embryonic cerebral neurons was studied. For this, varying amount of HgCl2 soution was injected to the developing eggs and the pattern of protein expression was studied using SDS-PAGE and the concentration of ATP was also measured. Total of 31 major protein bands were observed at 7th day of embryonic development. The amount of 330kDa, 320kDa and 45kDa proteins was reduced in HgCl2-treated embryos regardless of the amount of HgCl2 given. The amount of 285kDa and 24kDa proteins was reduced in embryos treated with relatively small amout(≤1.0 mg) of HgCl2 but increased in 2 mg HgCl2-treated embryos (138% of control). The amount of 250kDa protein was increased in all HgCl2-treated embryos. The 15kDa protein was seen only in embryos treated with 2 mg of HgCl2. The concentration of ATP was almost near to the normal level by the treatment with 1.0mg or less of HgCl2 and increased by 2 mg of HgCl2 (1.10×10-5 mol/ml) Total of 34 major protein bands were observed at 8th day of embryonic development. The amount of 330kDa and 320kDa was reduced in all HgCl2 -treated embryos. The amount of 285kDa protein was reduced by the treatment with relatively small amount(≤0.5 mg) of HgCl2 . However, the amount of this protein was increased by the treatment with larger amount(≥1.0 mg) of HgCl2 . The amount of 250kDa and 36kDa proteins were greatly increased in HgCl2 -treated embryos. The amount of increased by larger amount(≥0.5 mg) of HgCl2 in a dose-dependent manner. The amount of 22kDa protein was increased by the treatment with 1.0 mg or less of HgCl2 . However, the amount of this protein was markedly reduced by the treatment with 2.0 mg of HgCl2 (14% of control) The concentration of ATP was increased by the treatment with 1mg of HgCl2 (1.32×10-5 mol/ml) and even more increased by 2.0 mg of HgCl2 (5.35×10-5 mol/ml)

能動 Switched-Capacitor Filter에 관한 硏究

朴俊烈,具然健 弘益大學校 1981 弘大論叢 Vol.13 No.-

The Circuit of Switched capacitor integrator, which can be used as a basic block of filter design and has transfer functions independent of parasitic capacitances between any node and ground, is presented. The output characteristics when the duty cycle of trigger frequency is varied at 50%, and 25% are observed. The limitation of the sampling frequncy are defined. Ⅰ. 序 論 Ⅱ. 抵抗素子로서의 Switched-Capacitor Ⅲ. Miller積分器와 SC-積分器 Ⅳ. 實驗 및 考察 Ⅴ. 結 論 Ⅵ. 參考文獻 The Circuit of Switched capacitor integrator, which can be used as a basic block of filter design and has transfer functions independent of parasitic capacitances between any node and ground, is presented. The output characteristics when the duty cycle of trigger frequency is varied at 50%, and 25% are observed. The limitation of the sampling frequncy are defined.

High efficient fluorescence activated cell sorting through DNA nanostructure-based labeling complex

Yeong Gon ROH,Seung Won SHIN,Soong Ho UM 한국생물공학회 2017 한국생물공학회 학술대회 Vol.2017 No.4

Preparation and Properties of Polypropylene/Thermoplastic Polyester Elastomer Blends

Yeong Gon Kim(김영곤),Yeongseon Kim(김영선),Jin Kyu Choi(최진규),Sung-Hyeon Baeck(백성현),Sang Eun Shim(심상은) 한국고분자학회 2017 폴리머 Vol.41 No.3

폴리프로필렌/열가소성 폴리에스터 엘라스토머(PP/TPEE) 블렌드를 제조하였다. 두 상의 상용성을 증가시키기 위하여 maleic anhydride-grafted polypropylene(MA-g-PP)를 배합 도중 첨가하였다. SEM을 통한 모폴로지 분석결과, 두 상은 상용성이 없었으며 MA-g-PP를 첨가한 결과 상용성이 발현되어 MA-g-PP가 효과적인 상용화제로 작용하였다. MA-g-PP를 첨가한 PP/TPEE 블렌드는 XRD 분석 결과 20.9° 피크의 강도가 증가하였으며 21.6° 피크는 점차적으로 감소하였다. 상용화제가 첨가된 경우의 기계적 물성 증가는 SEM 및 XRD의 분석 결과와 부합하였다. DSC 분석 결과, TPEE의 함량이 증가할수록 결정화도가 감소하였으며 MA-g-PP가 첨가된 경우 상용성으로 인하여 단일의 유리전이온도가 관찰되었으며 열적 안정성이 증가되었다. Polypropylene (PP)/thermoplastic polyester elastomer (TPEE) blends were prepared. To enhance the compatibility between the two phases, maleic anhydride-grafted polypropylene (MA-g-PP) was applied during melt-mixing. The morphology obtained from scanning electron microscopy (SEM) showed that TPEE was not miscible with PP, however, those of the PP/TPEE/MA-g-PP indicated that PP and TPEE turned to miscible because MA-g-PP served as an effective compatibilizer. The tensile tests confirmed that the tensile strength of the PP/TPEE blends decreased and the elongation increased with increasing TPEE content. The increase in tensile strength of the PP/TPEE/MA-g-PP blends was associated with the morphology shown by SEM and internal structure. X-ray diffraction (XRD) confirmed that compared to the PP/TPEE blend, the intensity of the 20.9° peak of the PP/TPEE/MA-g-PP increased and that of the 21.6° peak decreased gradually due to the MA-g-PP. In differential scanning calorimetry (DSC), the crystallinity (Xc) of the PP/TPEE blends decreased with increasing TPEE content. The PP/TPEE/MA-g-PP blends showed a single weak glass transition (Tg) peak due to the compatibility between the PP and TPEE. The thermal stability of the PP/TPEE blends with MAg-PP was also higher than that of the PP/TPEE.

Synthesis of PLGA nanoparticles encapsulated by lipid via emulsion evaporation method for drug delivery platform

Yeong Gon ROH,Seung Won SHIN,Lunjakorn AMORNKITBAMRUNG,Soong Ho UM 한국생물공학회 2017 한국생물공학회 학술대회 Vol.2017 No.4

Hinokitiol Downregulates Melanosome-associated Protein Levels by Reducing Miff Expression

( Yeong Gon Choi ),( Eun Jin Bae ),( Dong Seok Kim ),( Sun Bang Kwon ),( Eun Sang Park ),( Jung Im Na ),( Kyoung Chan Park ) 대한피부과학회 2005 초록집 Vol.43 No.20

A Study on Image Change according to the Compressed Sensing Factor and the De-noising Factor during MRCP T2 3D

Yeong-Gon Kwak 대한자기공명기술학회 2021 대한자기공명기술학회지 Vol.31 No.2

고성능과 저전력을 고려한 IEEE 802.11n MAC(Medium Access Control) 설계

이영곤(Yeong-Gon Lee),정용진(Yong-Jin Jeong) 대한전자공학회 2007 대한전자공학회 학술대회 Vol.2007 No.11

본 논문애서는 고성능처리(high-throughput)가 가능하고 저전력을 고려한 802.11n MAC의 하드헤어와 소프트웨어 통합구조를 제안하였다. 제안된 MAC구조는 프레임 생성과 송신을 담당하는 송신블록과 프레임 수신과 채널 관리를 담당하는 수신블록, MAC과 스테이션의 정보를 관리하는 매니저블록, 하드웨어블록의 동작을 제어하는 콘트롤 블록으로 구성된다. 빠른 데이터 처리를 위해서 전송블록과 수신블록, 콘트롤 블록은 하드웨어로 설계하고 Gated Clock 저전력 기법을 적용했다. 매니저블록은 소프트웨어 설계를 통해서 동작의 효율성을 높였다. 현재 제안된 MAC구조의 상위 레벨 설계를 완성하였고, 상세 설계를 진행 중이다.

Protein Nanoparticle Fabrication for Optimized Reticuloendothelial System Evasion and Tumor Accumulation

Roh, Yeong Gon,Shin, Seung Won,Kim, Sun-Young,Kim, Sohyun,Lim, Yong Taik,Oh, Byung-Keun,Um, Soong Ho American Chemical Society 2019 Langmuir Vol.35 No.11

<P>Nanoparticles (NPs) of protein-based materials have become one of the most promising candidates for drug carriers in drug-delivery systems because of their in vivo nontoxicity, biodegradability, compatibility with hydrophilic drugs, and adaptability to the human body. Many studies have investigated the fabrication of protein NPs from human serum albumin (HSA) as a new drug carrier. It is important for these NPs to remain in the blood until they reach their therapeutic target to achieve the desired effect; the quicker the clearance of drugs from the body, the shorter is the residence time of drugs in the body, which eventually reduces drug efficacy. Macrophage uptake is a major mechanism for clearance of NPs from the body, so, reducing the degree of macrophage uptake is a major challenge in drug-delivery systems. Original studies of HSA NP uptake by macrophages showed that denatured HSA and HSA NPs synthesized with 80% (v/v) ethanol showed a high degree of macrophage uptake. We found that HSA NPs synthesized with lower ethanol content at pH 7 showed lower macrophage uptake in in vitro macrophage cellular uptake experiments. The effects of the preparation parameters of ethanol concentration, pH, and glutaraldehyde on the macrophage uptake of NPs were thoroughly studied. This newly developed protein NP with lower macrophage uptake has potential application as a drug carrier for many delivery systems.</P> [FIG OMISSION]</BR>