In this work, a hetero-epitaxial Al0.49In0.51As/Ga0.47In0.53 As metamorphic high electron mobility transistor(mHEMT) grown by metal–organic chemical vapor deposition(MOCVD) on p-type silicon substrate has been succes...In this work, a hetero-epitaxial Al0.49In0.51As/Ga0.47In0.53 As metamorphic high electron mobility transistor(mHEMT) grown by metal–organic chemical vapor deposition(MOCVD) on p-type silicon substrate has been successfully demonstrated. A novel AlGaAs/Al As period multiple quantum well(MQW) composite buffer scheme is developed to effectively tune the leakage current from the buffer layer. The quantized room-temperature Hall mobility of the twodimensional electron gas(2DEG) is larger than 7800 cm2/V·s, with an average sheet carrier density of 4.6×1012cm-2.Two-stage electron beam(EB) lithography technology by a JBX-6300 e-beam lithography system is developed to realize a 0.13-μm m HEMT device on Si substrate. A maximum transconductance Gm of up to 854 mS/mm is achieved, and is comparable to that of m HEMT technology on Ga As substrate with the same dimension. The fTand fmax are 135 GHz and120 GHz, respectively.展开更多
One of the most interesting questions of video streaming over the Intemet is packet loss. Some error resilient technologies have been proposed to overcome quality decrease of reconsixucted video occurred due to packet...One of the most interesting questions of video streaming over the Intemet is packet loss. Some error resilient technologies have been proposed to overcome quality decrease of reconsixucted video occurred due to packet loss, in which optimized reconstructionbased DCT （ORB-DCT） utilizes two-direction interleaving. An improved ORB-DCT （IORB-DCT）, which uses four-direction interleaving, is proposed in this paper. Experimental results are demonstrated to verify the effectiveness of the proposed IORB-DCT.展开更多
The relative frequency of depression in people with primary progressive multip le sclerosis (PPMS) (30 patients) compared with those with a history of relapse (106 patients) was determined.Three participants in the pr...The relative frequency of depression in people with primary progressive multip le sclerosis (PPMS) (30 patients) compared with those with a history of relapse (106 patients) was determined.Three participants in the progressive group and 28 in the relapsing group had a lifetime history of major depression.The lifetime morbidity ratio for major depression in relapsing patients was 2.64 compared wit h that of PPMS.展开更多
Recent progress made in the prediction,characterisation,and mitigation of multipactor discharge is reviewed for single‐and two‐surface geometries.First,an overview of basic concepts including secondary electron emis...Recent progress made in the prediction,characterisation,and mitigation of multipactor discharge is reviewed for single‐and two‐surface geometries.First,an overview of basic concepts including secondary electron emission,electron kinetics under the force law,multipactor susceptibility,and saturation mechanisms is provided,followed by a discus-sion on multipactor mitigation strategies.These strategies are categorised into two broad areas–mitigation by engineered devices and engineered radio frequency(rf)fields.Each approach is useful in different applications.Recent advances in multipactor physics and engineering during the past decade,such as novel multipactor prediction methods,un-derstanding space charge effects,schemes for controlling multipacting particle trajec-tories,frequency domain analysis,high frequency effects,and impact on rf signal quality are presented.In addition to vacuum electron multipaction,multipactor‐induced ioni-zation breakdown is also reviewed,and the recent advances are summarised.展开更多
The vibration-rotation spectra of N2O are among the most thoroughly investigated IR spectra in the literature. Recently, the observation made by C. Amiot et al. gave molecular constants with great precision. There is,...The vibration-rotation spectra of N2O are among the most thoroughly investigated IR spectra in the literature. Recently, the observation made by C. Amiot et al. gave molecular constants with great precision. There is, however, no information yet on the Q branch of the 2110—0110 band.展开更多
基金supported by the Young Scientists Fund of the National Natural Science Foundation of China(Grant No.61401373)the Fundamental Research Funds for Central University,China(Grant Nos.XDJK2013B004 and 2362014XK13)the Chongqing Natural Science Foundation,China(Grant No.cstc2014jcyj A40038)
文摘In this work, a hetero-epitaxial Al0.49In0.51As/Ga0.47In0.53 As metamorphic high electron mobility transistor(mHEMT) grown by metal–organic chemical vapor deposition(MOCVD) on p-type silicon substrate has been successfully demonstrated. A novel AlGaAs/Al As period multiple quantum well(MQW) composite buffer scheme is developed to effectively tune the leakage current from the buffer layer. The quantized room-temperature Hall mobility of the twodimensional electron gas(2DEG) is larger than 7800 cm2/V·s, with an average sheet carrier density of 4.6×1012cm-2.Two-stage electron beam(EB) lithography technology by a JBX-6300 e-beam lithography system is developed to realize a 0.13-μm m HEMT device on Si substrate. A maximum transconductance Gm of up to 854 mS/mm is achieved, and is comparable to that of m HEMT technology on Ga As substrate with the same dimension. The fTand fmax are 135 GHz and120 GHz, respectively.
文摘One of the most interesting questions of video streaming over the Intemet is packet loss. Some error resilient technologies have been proposed to overcome quality decrease of reconsixucted video occurred due to packet loss, in which optimized reconstructionbased DCT （ORB-DCT） utilizes two-direction interleaving. An improved ORB-DCT （IORB-DCT）, which uses four-direction interleaving, is proposed in this paper. Experimental results are demonstrated to verify the effectiveness of the proposed IORB-DCT.
文摘The relative frequency of depression in people with primary progressive multip le sclerosis (PPMS) (30 patients) compared with those with a history of relapse (106 patients) was determined.Three participants in the progressive group and 28 in the relapsing group had a lifetime history of major depression.The lifetime morbidity ratio for major depression in relapsing patients was 2.64 compared wit h that of PPMS.
文摘Recent progress made in the prediction,characterisation,and mitigation of multipactor discharge is reviewed for single‐and two‐surface geometries.First,an overview of basic concepts including secondary electron emission,electron kinetics under the force law,multipactor susceptibility,and saturation mechanisms is provided,followed by a discus-sion on multipactor mitigation strategies.These strategies are categorised into two broad areas–mitigation by engineered devices and engineered radio frequency(rf)fields.Each approach is useful in different applications.Recent advances in multipactor physics and engineering during the past decade,such as novel multipactor prediction methods,un-derstanding space charge effects,schemes for controlling multipacting particle trajec-tories,frequency domain analysis,high frequency effects,and impact on rf signal quality are presented.In addition to vacuum electron multipaction,multipactor‐induced ioni-zation breakdown is also reviewed,and the recent advances are summarised.
文摘The vibration-rotation spectra of N2O are among the most thoroughly investigated IR spectra in the literature. Recently, the observation made by C. Amiot et al. gave molecular constants with great precision. There is, however, no information yet on the Q branch of the 2110—0110 band.
文摘Y2002-63121-458 0219792线性控制宽频带 CMOS 衰减器=A linear-control wide-band cMOS attenuator[会,英]/Kaunisto.R.& Korpi,P.//The IEEE Internadonal Symposium on Circuits andSystems Vol.4 of 5.—458～461(HE)Y2002-63121-666 0219793基于规范符号数字码的低功率无乘法器 FIR 滤波合成器=Low-power muitiplierless FIR filter synthesizerbased on CSD code[会,英]/Lin,M..C.& Chen,C.L.//The IEEE International Symposium on Circuits andSystems Vol.4 of 5.—666～669(HE)
