The equations of electrodynamics for a gyrotropic medium by using Maxwell’s equa-tions are deduced.Through Fourier transformation,the admittances of TM and TE modes inthe electrically gyrotropic substrate and magneti...The equations of electrodynamics for a gyrotropic medium by using Maxwell’s equa-tions are deduced.Through Fourier transformation,the admittances of TM and TE modes inthe electrically gyrotropic substrate and magnetically gyrotropic substrate are given.Numericalresults of the dominant mode in magnetized ferrite-loaded double-layered finlines are presentedwhich could be used in designing finline ferrite devices.展开更多
A novel topology of the current-source grid-connected inverter is proposed based on the immittance converter theory. A control strategy of sine-sine pulse width modulation (PWM) is studied. Compared with the traditi...A novel topology of the current-source grid-connected inverter is proposed based on the immittance converter theory. A control strategy of sine-sine pulse width modulation (PWM) is studied. Compared with the traditional current-source inverter, the power frequency inductors and power frequency transformer are replaced with high frequency inductors and a high frequency transformer. Thus, the proposed inverter has advantages of small volume, low cost, low total harmonic distortion (THD), low power losses, high power factor (PF) and simple control. Furthermore, grid voltage cannot influence output current of the grid-connected inverter and the current-source inverter with a high PF that approaches one has been realized. Finally, validity of the theory analysis and feasibility of the control scheme are shown by simulation and experimental results.展开更多
The immittance spectral frequencies (ISFs) is proposed as a new set of classification features and compared with the linear spectral frequencies (LSFs) applied in a frame-level wideband speech/music discrimination...The immittance spectral frequencies (ISFs) is proposed as a new set of classification features and compared with the linear spectral frequencies (LSFs) applied in a frame-level wideband speech/music discrimination system. These two sets of features can be shared by the classifier and coding module to reduce the total computational complexity, making our classification system suitable for multi-mode audio coding applications. A performance assessment and comparison of the features are made. The experiment results show that the ISFs and LSFs have similar good performance when using full covariance matrices in classification models and the ISFs perform slightly better when using diagonal matrices. Their statistical differences for speech and music signals are also revealed.展开更多
文摘The equations of electrodynamics for a gyrotropic medium by using Maxwell’s equa-tions are deduced.Through Fourier transformation,the admittances of TM and TE modes inthe electrically gyrotropic substrate and magnetically gyrotropic substrate are given.Numericalresults of the dominant mode in magnetized ferrite-loaded double-layered finlines are presentedwhich could be used in designing finline ferrite devices.
基金supported by the Shanghai Leading Academic Discipline Project (Grant No.T0103)
文摘A novel topology of the current-source grid-connected inverter is proposed based on the immittance converter theory. A control strategy of sine-sine pulse width modulation (PWM) is studied. Compared with the traditional current-source inverter, the power frequency inductors and power frequency transformer are replaced with high frequency inductors and a high frequency transformer. Thus, the proposed inverter has advantages of small volume, low cost, low total harmonic distortion (THD), low power losses, high power factor (PF) and simple control. Furthermore, grid voltage cannot influence output current of the grid-connected inverter and the current-source inverter with a high PF that approaches one has been realized. Finally, validity of the theory analysis and feasibility of the control scheme are shown by simulation and experimental results.
文摘The immittance spectral frequencies (ISFs) is proposed as a new set of classification features and compared with the linear spectral frequencies (LSFs) applied in a frame-level wideband speech/music discrimination system. These two sets of features can be shared by the classifier and coding module to reduce the total computational complexity, making our classification system suitable for multi-mode audio coding applications. A performance assessment and comparison of the features are made. The experiment results show that the ISFs and LSFs have similar good performance when using full covariance matrices in classification models and the ISFs perform slightly better when using diagonal matrices. Their statistical differences for speech and music signals are also revealed.