• 제목/요약/키워드: 77K

검색결과 12,925건 처리시간 0.044초

A 77 GHz 3-Stage Low Noise Amplifier with Cascode Structure Utilizing Positive Feedback Network using 0.13 μm CMOS Process

  • Lee, Choong-Hee;Choi, Woo-Yeol;Kim, Ji-Hoon;Kwon, Young-Woo
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • 제8권4호
    • /
    • pp.289-294
    • /
    • 2008

  • A 77 GHz 3-stage low noise amplifier (LNA) employing one common source and two cascode stages is developed using $0.13{\mu}m$ CMOS process. To compensate for the low gain which is caused by lossy silicon substrate and parasitic element of CMOS transistor, positive feedback technique using parasitic inductance of bypass capacitor is adopted to cascode stages. The developed LNA shows gain of 7.2 dB, Sl1 of -16.5 dB and S22 of -19.8 dB at 77 GHz. The return loss bandwidth of LNA is 71.6 to 80.9 GHz (12%). The die size is as small as $0.7mm\times0.8mm$ by using bias line as inter-stage matching networks. This LNA shows possibility of 77 GHz automotive RADAR system using $0.13{\mu}m$ CMOS process, which has advantage in cost compared to sub-100 nm CMOS process.

  • https://doi.org/10.5573/JSTS.2008.8.4.289 인용 PDF KSCI

XRCC1-77T>C Polymorphism and Cancer Risk: A Meta-analysis

  • Wang, Yong-Gang;Zheng, Tian-Ying
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제13권1호
    • /
    • pp.111-115
    • /
    • 2012

  • Variants of X-ray repair cross-complementing group 1 (XRCC1) are involved in the development of cancer, but studies investigating the association of XRCC1-77T>C polymorphism with cancer risk have reported conflicting results. To clarify the effect of the XRCC1 -77T>C polymorphism on cancer risk, we performed a meta-analysis by conducting searches of the published literature in PubMed, Embase and CBM databases. Finally, 13 studies were included into our meta-analysis, involving a total of 11, 678 individuals. Subgroup analyses were performed by ethnicity and cancer type. The results of this meta-analysis showed that there was significant association between the C variant of XRCC1-77T>C polymorphism and cancer risk in all four genetic comparison models (ORC vs. T =1.19, 95%CI 1.07-1.31, P = 0.001; OR homozygote model =1.28, 95%CI 1.07-1.52, P = 0.007; OR recessive genetic model =1.22, 95%CI 1.04-1.44, P = 0.015; OR dominant model =1.21, 95% CI 1.07-1.35, P = 0.001). In the subgroup analyses based on ethnicity, the association was still significant in the Asian population (all p values<0.001), but not in the Caucasian population (all p values > 0.05). Thus, the XRCC1 -77T>C polymorphism is associated with cancer risk, and individuals with XRCC1 -77C variant have a significantly higher cancer risk, particularly in the Asian population.

  • https://doi.org/10.7314/APJCP.2012.13.1.111 인용 PDF KSCI

Effect of Co-Substitution on the Crystallization and Magnetic Properties of a Mechanically Milled Nd15(Fe1-xCox)77B8 (x=0-0.6) Alloy

  • Kwon, H.W.;Yang, C.J.
    • Journal of Magnetics
    • /
    • 제7권4호
    • /
    • pp.143-146
    • /
    • 2002

  • Mechanical milling technique is considered to be a useful way of processing the fine Nd-Fe-B-type powder with high coercivity. In the present study, phase evolution of the $Nd_{15}(Fe_{1-x}Co_{x})_{77}B_{8}$ (x=0-0.6) alloys during the high energy mechanical milling and annealing was investigated. The effect of Co-substitution on the crystallization of the mechanically milled $Nd_{15}(Fe_{1-x}Co_{x})_{77}B_{8}$ amorphous material was examined. The Nd-Fe-B-type alloys can be amorphized completely by a high-energy mechanical milling. On annealing of the amorphous material, fine $\alpha$-Fe crystallites form first from the amorphous. These fine $\alpha$-Fe crystallites reacts with the remaining amorphous afterwards, leading to crystallization to $Nd_2Fe_{14}$B phase. The Co-substitution for Fe in $Nd_{15}(Fe_{1-x}Co_{x})_{77}B_{8}$ ($\mu$x=0∼0.6) alloys lower significantly the crystallization temperature of the amorphous phase to the $Nd_2Fe_{14}$B phase. The mechanically milled and annealed $Nd_{15}Fe_{77}B_8$ alloy without Co-substitution exhibits consistently better magnetic properties with respect to the alloys with Co-substitution.

  • https://doi.org/10.4283/JMAG.2002.7.4.143 인용 PDF KSCI