The quantitative structure-property relationship(QSPR) of anabolic androgenic steroids was studied on the half-wave reduction potential(E1/2) using quantum and physico-chemical molecular descriptors. The descriptors w...The quantitative structure-property relationship(QSPR) of anabolic androgenic steroids was studied on the half-wave reduction potential(E1/2) using quantum and physico-chemical molecular descriptors. The descriptors were calculated by semi-empirical calculations. Models were established using partial least square(PLS) regression and back-propagation artificial neural network(BP-ANN). The QSPR results indicate that the descriptors of these derivatives have significant relationship with half-wave reduction potential. The stability and prediction ability of these models were validated using leave-one-out cross-validation and external test set.展开更多
China-ADS project, a continuous wave (CW) proton accelerator and aims to design and build an ADS demonstration facility has been proposed and launched actively in China. HWR ( =0.10) superconducting cavity with freque...China-ADS project, a continuous wave (CW) proton accelerator and aims to design and build an ADS demonstration facility has been proposed and launched actively in China. HWR ( =0.10) superconducting cavity with frequency of 162.5 MHz is applied to one of the parallel injectors prompted by Institute of Modern Physics (IMP)[1].展开更多
A novel thin-film lithium niobate(TFLN) electro-optic modulator is proposed and demonstrated. LiNbO_(3)-silica hybrid waveguide is adopted to maintain low optical loss for an electrode spacing as narrow as 3 μm, resu...A novel thin-film lithium niobate(TFLN) electro-optic modulator is proposed and demonstrated. LiNbO_(3)-silica hybrid waveguide is adopted to maintain low optical loss for an electrode spacing as narrow as 3 μm, resulting in a low halfwave-voltage length product of only 1.7 V·cm. Capacitively loaded traveling-wave electrodes are employed to reduce the microwave loss, while a quartz substrate is used in place of a silicon substrate to achieve velocity matching. The fabricated TFLN modulator with a 5-mm-long modulation region exhibits a half-wave voltage of 3.4 V and a merely less than 2 d B roll-off in an electro-optic response up to 67 GHz.展开更多
In this paper, we theoretically deduce the expressions of half-wave voltage and 3-dB modulation bandwidth in which conductor loss is taken into account. The results suggest that it will affect the theoretical values o...In this paper, we theoretically deduce the expressions of half-wave voltage and 3-dB modulation bandwidth in which conductor loss is taken into account. The results suggest that it will affect the theoretical values of half-wave voltage and bandwidth as well as the optimized electrode's dimension whether considering the conductor loss or not. As an example, we present a Mach-Zehnder (MZ) type polymer waveguide amplitude modulator. The half-wave voltage increases by 1 V and the 3-dB bandwidth decreases by 30% when the conductor loss is taken into account. Besides, the effects of impedance mismatching and velocity mismatching between microwave and light wave on the half-wave voltage, and 3-dB bandwidth are discussed.展开更多
The voltage characteristics of a half-wavelength transmission(HWLT)system lack mechanism explanation and systematic summary.In this paper,both the steady-state and fault voltage characteristics are analyzed and explai...The voltage characteristics of a half-wavelength transmission(HWLT)system lack mechanism explanation and systematic summary.In this paper,both the steady-state and fault voltage characteristics are analyzed and explained based on the wave process method.An analysis model is established for HWLT lines and wave propagation equations with different terminal conditions are deduced.For steady-state conditions,voltage profiles along HWLT lines are depicted and partial overvoltage occurs when there is an overload or low-power factor.In addition,fault voltage characteristics are analyzed under load-rejection or short-circuit conditions.The series resonance overvoltage will happen when short-circuit faults occur at certain positions and its peak value is influenced by grid strength or fault type.Furthermore,a refined transmission line model is presented to consider non-ideal factors and simulation results demonstrate that geomorphic conditions and electromagnetic environments influence line voltage characteristics to a certain extent.展开更多
A bias-independent inter-modulation method is proposed and demonstrated for measuring low-frequency modulation and bias half-wave voltages of Mach-Zehnder modulators(MZMs).The method consists of simultaneous sinusoida...A bias-independent inter-modulation method is proposed and demonstrated for measuring low-frequency modulation and bias half-wave voltages of Mach-Zehnder modulators(MZMs).The method consists of simultaneous sinusoidal modulation on the modulation and bias ports of the MZM under test.Sinusoidal-modulated sidebands heterodyne with each other and generate the desired inter-modulation products after photodetection,which allows extracting both the modulation depth and half-wave voltage for the modulation and bias ports of the MZM.Our method is independent of bias voltages of the MZM,which can be canceled out by carefully choosing the sinusoidal-modulation frequencies.Moreover,the proposed method enables the low swing voltage for measuring both the modulation depth and half-wave voltage of MZMs.Experiments indicate that the proposed method features the simple setup and high accuracy for low-frequency response measurement ranging from 1 Hz to 1 MHz.展开更多
为了消除含全波机械整流器减速带馈能装置的发电量和系统可靠性受到复位弹簧刚度的约束,提出了一种基于半波机械整流器的双减速带馈能装置(Dual-speed Bump Energy Harvester,DBEH)。该装置利用机械传动模块将两条减速带在车轮驱动下的...为了消除含全波机械整流器减速带馈能装置的发电量和系统可靠性受到复位弹簧刚度的约束,提出了一种基于半波机械整流器的双减速带馈能装置(Dual-speed Bump Energy Harvester,DBEH)。该装置利用机械传动模块将两条减速带在车轮驱动下的向下线性运动转换成单个发电机轴的单向旋转运动,将机械能转换成电能。单向的运动转换降低了对复位弹簧载荷的要求。建立了车轮激励以及减速带动力学理论模型并通过了道路试验的验证。基于理论模型的数值仿真研究了双馈能减速带的发电性能。研究结果表明,系统的均方根(Root Mean Square,RMS)功率与输出电能随着外部激励幅值的增加,以及弹簧刚度的减小而增加;当负载电阻阻值为7~9Ω时,系统的输出性能最优;与减小小齿轮半径相比,增大齿轮箱的增速比对系统输出的提升影响更明显;小惯量的飞轮更能有效提高系统对机械能的捕获与机械能到电能的转化率。展开更多
Based on the equivalence principle of deflection and stress, the concentrated vehicle load which acts on the center of continuously reinforced concrete pavement （CRCP） is translated into the equivalent half-wave sin...Based on the equivalence principle of deflection and stress, the concentrated vehicle load which acts on the center of continuously reinforced concrete pavement （CRCP） is translated into the equivalent half-wave sine load by the Fourier transform. On the basis of this transform and the small deflection theory of elastic thin plates, the deflection and stress formulae of CRCP under the concentrated vehicle load with a hollow foundation are put forward. The sensitivity of parameters is analyzed. The results show that maximum deflection is directly proportional to the concentrated vehicle load and the slab width, and inversely proportional to the lateral bending stiffness and slab thickness. The effects of slab width and thickness are significant with regard to maximum deflection. Maximum stress is directly proportional to the concentrated vehicle load and the slab width as well as inversely proportional to slab thickness. The effect of slab thickness is significant with regard to maximum stress. According to the calculation results, the most effective measure to reduce maximum deflection and stress is to increase slab thickness.展开更多
基金Project supported by the Postdoctoral Science Foundation of Central South University,ChinaProject(2015SK20823)supported by Science and Technology Project of Hunan Province,China+2 种基金Project(15A001)supported by Scientific Research Fund of Hunan Provincial Education Department,ChinaProject(CX2015B372)supported by Hunan Provincial Innovation Foundation for Postgraduate,ChinaProject supported by Innovation Experiment Program for University Students of Changsha University of Science and Technology,China
文摘The quantitative structure-property relationship(QSPR) of anabolic androgenic steroids was studied on the half-wave reduction potential(E1/2) using quantum and physico-chemical molecular descriptors. The descriptors were calculated by semi-empirical calculations. Models were established using partial least square(PLS) regression and back-propagation artificial neural network(BP-ANN). The QSPR results indicate that the descriptors of these derivatives have significant relationship with half-wave reduction potential. The stability and prediction ability of these models were validated using leave-one-out cross-validation and external test set.
文摘China-ADS project, a continuous wave (CW) proton accelerator and aims to design and build an ADS demonstration facility has been proposed and launched actively in China. HWR ( =0.10) superconducting cavity with frequency of 162.5 MHz is applied to one of the parallel injectors prompted by Institute of Modern Physics (IMP)[1].
基金supported in part by the National Key R&D Program of China(No.2018YFB2201701)National Natural Science Foundation of China(Nos.61975093,61927811,61991443,61822404,61974080,61904093,and 61875104)+1 种基金Key Lab Program of BNRist(No.BNR2019ZS01005),China Postdoctoral Science Foundation(No.2019T120090)Collaborative Innovation Centre of Solid-State Lighting and Energy-Saving Electronics。
文摘A novel thin-film lithium niobate(TFLN) electro-optic modulator is proposed and demonstrated. LiNbO_(3)-silica hybrid waveguide is adopted to maintain low optical loss for an electrode spacing as narrow as 3 μm, resulting in a low halfwave-voltage length product of only 1.7 V·cm. Capacitively loaded traveling-wave electrodes are employed to reduce the microwave loss, while a quartz substrate is used in place of a silicon substrate to achieve velocity matching. The fabricated TFLN modulator with a 5-mm-long modulation region exhibits a half-wave voltage of 3.4 V and a merely less than 2 d B roll-off in an electro-optic response up to 67 GHz.
文摘In this paper, we theoretically deduce the expressions of half-wave voltage and 3-dB modulation bandwidth in which conductor loss is taken into account. The results suggest that it will affect the theoretical values of half-wave voltage and bandwidth as well as the optimized electrode's dimension whether considering the conductor loss or not. As an example, we present a Mach-Zehnder (MZ) type polymer waveguide amplitude modulator. The half-wave voltage increases by 1 V and the 3-dB bandwidth decreases by 30% when the conductor loss is taken into account. Besides, the effects of impedance mismatching and velocity mismatching between microwave and light wave on the half-wave voltage, and 3-dB bandwidth are discussed.
基金supported by the State Grid Corporation of China(No.SGSDDK00KJJS1600149).
文摘The voltage characteristics of a half-wavelength transmission(HWLT)system lack mechanism explanation and systematic summary.In this paper,both the steady-state and fault voltage characteristics are analyzed and explained based on the wave process method.An analysis model is established for HWLT lines and wave propagation equations with different terminal conditions are deduced.For steady-state conditions,voltage profiles along HWLT lines are depicted and partial overvoltage occurs when there is an overload or low-power factor.In addition,fault voltage characteristics are analyzed under load-rejection or short-circuit conditions.The series resonance overvoltage will happen when short-circuit faults occur at certain positions and its peak value is influenced by grid strength or fault type.Furthermore,a refined transmission line model is presented to consider non-ideal factors and simulation results demonstrate that geomorphic conditions and electromagnetic environments influence line voltage characteristics to a certain extent.
基金supported in part by the National Natural Science Foundation of China(Grant No.61927821)National Key Research and Development Program ofChina(Grant No.2018YFE0201900)Fundamental Research Funds for the Central Universities(Grant No.ZYGX2019Z011).
文摘A bias-independent inter-modulation method is proposed and demonstrated for measuring low-frequency modulation and bias half-wave voltages of Mach-Zehnder modulators(MZMs).The method consists of simultaneous sinusoidal modulation on the modulation and bias ports of the MZM under test.Sinusoidal-modulated sidebands heterodyne with each other and generate the desired inter-modulation products after photodetection,which allows extracting both the modulation depth and half-wave voltage for the modulation and bias ports of the MZM.Our method is independent of bias voltages of the MZM,which can be canceled out by carefully choosing the sinusoidal-modulation frequencies.Moreover,the proposed method enables the low swing voltage for measuring both the modulation depth and half-wave voltage of MZMs.Experiments indicate that the proposed method features the simple setup and high accuracy for low-frequency response measurement ranging from 1 Hz to 1 MHz.
文摘为了消除含全波机械整流器减速带馈能装置的发电量和系统可靠性受到复位弹簧刚度的约束,提出了一种基于半波机械整流器的双减速带馈能装置(Dual-speed Bump Energy Harvester,DBEH)。该装置利用机械传动模块将两条减速带在车轮驱动下的向下线性运动转换成单个发电机轴的单向旋转运动,将机械能转换成电能。单向的运动转换降低了对复位弹簧载荷的要求。建立了车轮激励以及减速带动力学理论模型并通过了道路试验的验证。基于理论模型的数值仿真研究了双馈能减速带的发电性能。研究结果表明,系统的均方根(Root Mean Square,RMS)功率与输出电能随着外部激励幅值的增加,以及弹簧刚度的减小而增加;当负载电阻阻值为7~9Ω时,系统的输出性能最优;与减小小齿轮半径相比,增大齿轮箱的增速比对系统输出的提升影响更明显;小惯量的飞轮更能有效提高系统对机械能的捕获与机械能到电能的转化率。
基金The Science Foundation of Ministry of Transport of the People's Republic of China(No.200731822301-7)
文摘Based on the equivalence principle of deflection and stress, the concentrated vehicle load which acts on the center of continuously reinforced concrete pavement （CRCP） is translated into the equivalent half-wave sine load by the Fourier transform. On the basis of this transform and the small deflection theory of elastic thin plates, the deflection and stress formulae of CRCP under the concentrated vehicle load with a hollow foundation are put forward. The sensitivity of parameters is analyzed. The results show that maximum deflection is directly proportional to the concentrated vehicle load and the slab width, and inversely proportional to the lateral bending stiffness and slab thickness. The effects of slab width and thickness are significant with regard to maximum deflection. Maximum stress is directly proportional to the concentrated vehicle load and the slab width as well as inversely proportional to slab thickness. The effect of slab thickness is significant with regard to maximum stress. According to the calculation results, the most effective measure to reduce maximum deflection and stress is to increase slab thickness.
