Because muzzle impulse noise could cause damage to or have an intluence on the operator, tiae ettecnve protecnve measures should be taken. Therefore, correct analysis of impulse noise characteristics is very significa...Because muzzle impulse noise could cause damage to or have an intluence on the operator, tiae ettecnve protecnve measures should be taken. Therefore, correct analysis of impulse noise characteristics is very significant. Considering the shortcomings of fast Fourier transform method (FFT) in analysis of muzzle impulse noise frequency characteristics, wavelet energy spectrum method is put forward. Based on specific experiment data, the frequency characteristics and spectral energy dis tribution can be obtained. The experiment results show that wavelet energy spectrum method is applicable in muzzle impulse noise characteristic analysis.展开更多
This paper analyses a key problem in the quantification of pulse diagnosis. Due to the subjectivity and fuzziness of pulse diagnosis,quantitative methods are needed. To extract the parameters of pulse signals,the prer...This paper analyses a key problem in the quantification of pulse diagnosis. Due to the subjectivity and fuzziness of pulse diagnosis,quantitative methods are needed. To extract the parameters of pulse signals,the prerequisite is to detect the corners of pulse signals correctly. Up to now,the pulse parameters are mostly acquired by marking the pulse corners manually,which is an obstacle to modernize pulse diagnosis. Therefore,a new automatic parameters extraction approach for pulse signals using wavelet transform is presented. The results testified that the method we proposed is feasible and effective and can detect corners of pulse signals accurately,which can be expected to facilitate the modernization of pulse diagnosis.展开更多
The wavelet packet is presented as a new kind of multiscale analysis technique followed by Wavelet analysis. The fundamental and realization arithmetic of the wavelet packet analysis method are described in this paper...The wavelet packet is presented as a new kind of multiscale analysis technique followed by Wavelet analysis. The fundamental and realization arithmetic of the wavelet packet analysis method are described in this paper. A new application approach of the wavelet packed method to extract the feature of the pulse signal from energy distributing angle is expatiated. It is convenient for the microchip to process and judge by using the wavelet packet analysis method to make the pulse signals quantized and analyzed. Kinds of experiments are simulated in the lab, and the experiments prove that it is a convenient and accurate method to extract the feature of the pulse signal based on wavelet packed-energy spectrumanalysis.展开更多
We propose a scheme to simultaneously widen and heighten the high-order harmonic plateau on a large scale. More specifically, by adopting a united two-atom system with a suitable inter-nuclear separation instead of a ...We propose a scheme to simultaneously widen and heighten the high-order harmonic plateau on a large scale. More specifically, by adopting a united two-atom system with a suitable inter-nuclear separation instead of a single-atom, the harmonic plateau is widened from Ip + 3.2Up to Ip +8.5Up; further, by adopting the combined pulse, the extended plateau (harmonics near Ip+ 5.6Up) is selectively heightened in excess of 4 orders of magnitude compared with the case of the low-frequency pulse alone. By means of the wavelet transform for the induced dipole of these harmonics, a single x-ray pulse as short as 210 asec is achieved.展开更多
Based on the general formula for finding qualified mother wavelets [Opt. Lett. 31 (2006) 407] we make wavelet transforms computed with the newly found mother wavelets (characteristic of the power 2n) for some opti...Based on the general formula for finding qualified mother wavelets [Opt. Lett. 31 (2006) 407] we make wavelet transforms computed with the newly found mother wavelets (characteristic of the power 2n) for some optical Gaussian pulses, which exhibit the ability to measure frequency of the pulse more precisely and clearly. We also work with complex mother wavelets composed of new real mother wavelets, which offer the ability of obtaining phase information of the pulse as well as amplitude information. The analogy between the behavior of Hermite Gauss beams and that of new wavelet transforms is noticed.展开更多
When the envelope of the conducting strips for the input transducer of magnetostatic surface wave(MSSW) device is designed according to the wavelet-function envelope,the impulse-response function of the input transduc...When the envelope of the conducting strips for the input transducer of magnetostatic surface wave(MSSW) device is designed according to the wavelet-function envelope,the impulse-response function of the input transducer for MSSW device is equal to the wavelet function,so that single-scale wavelet-transform processor of MSSW type is fabricated.First,according to the envelope function of the wavelet,the length function of the conducting strips is defined,then,the lengths of the conducting strips can be calculated from the length function of the conducting strips,finally,the input transducer can be designed according to the lengths and widths for the conducting strips.The compensation method of the insertion loss for single-scale wavelet trans-form processor of MSSW type is also given in the paper.When the output end of single-scale wavelet transform processor of MSSW type is connected to the amplifier,its insertion loss can be compensated.展开更多
文摘Because muzzle impulse noise could cause damage to or have an intluence on the operator, tiae ettecnve protecnve measures should be taken. Therefore, correct analysis of impulse noise characteristics is very significant. Considering the shortcomings of fast Fourier transform method (FFT) in analysis of muzzle impulse noise frequency characteristics, wavelet energy spectrum method is put forward. Based on specific experiment data, the frequency characteristics and spectral energy dis tribution can be obtained. The experiment results show that wavelet energy spectrum method is applicable in muzzle impulse noise characteristic analysis.
文摘This paper analyses a key problem in the quantification of pulse diagnosis. Due to the subjectivity and fuzziness of pulse diagnosis,quantitative methods are needed. To extract the parameters of pulse signals,the prerequisite is to detect the corners of pulse signals correctly. Up to now,the pulse parameters are mostly acquired by marking the pulse corners manually,which is an obstacle to modernize pulse diagnosis. Therefore,a new automatic parameters extraction approach for pulse signals using wavelet transform is presented. The results testified that the method we proposed is feasible and effective and can detect corners of pulse signals accurately,which can be expected to facilitate the modernization of pulse diagnosis.
文摘The wavelet packet is presented as a new kind of multiscale analysis technique followed by Wavelet analysis. The fundamental and realization arithmetic of the wavelet packet analysis method are described in this paper. A new application approach of the wavelet packed method to extract the feature of the pulse signal from energy distributing angle is expatiated. It is convenient for the microchip to process and judge by using the wavelet packet analysis method to make the pulse signals quantized and analyzed. Kinds of experiments are simulated in the lab, and the experiments prove that it is a convenient and accurate method to extract the feature of the pulse signal based on wavelet packed-energy spectrumanalysis.
基金Supported by the National Natural Science Foundation of China under Grant No. 10474028
文摘We propose a scheme to simultaneously widen and heighten the high-order harmonic plateau on a large scale. More specifically, by adopting a united two-atom system with a suitable inter-nuclear separation instead of a single-atom, the harmonic plateau is widened from Ip + 3.2Up to Ip +8.5Up; further, by adopting the combined pulse, the extended plateau (harmonics near Ip+ 5.6Up) is selectively heightened in excess of 4 orders of magnitude compared with the case of the low-frequency pulse alone. By means of the wavelet transform for the induced dipole of these harmonics, a single x-ray pulse as short as 210 asec is achieved.
文摘Based on the general formula for finding qualified mother wavelets [Opt. Lett. 31 (2006) 407] we make wavelet transforms computed with the newly found mother wavelets (characteristic of the power 2n) for some optical Gaussian pulses, which exhibit the ability to measure frequency of the pulse more precisely and clearly. We also work with complex mother wavelets composed of new real mother wavelets, which offer the ability of obtaining phase information of the pulse as well as amplitude information. The analogy between the behavior of Hermite Gauss beams and that of new wavelet transforms is noticed.
基金supported by the National Natural Science Foundation of China (Grant No 60976058)
文摘When the envelope of the conducting strips for the input transducer of magnetostatic surface wave(MSSW) device is designed according to the wavelet-function envelope,the impulse-response function of the input transducer for MSSW device is equal to the wavelet function,so that single-scale wavelet-transform processor of MSSW type is fabricated.First,according to the envelope function of the wavelet,the length function of the conducting strips is defined,then,the lengths of the conducting strips can be calculated from the length function of the conducting strips,finally,the input transducer can be designed according to the lengths and widths for the conducting strips.The compensation method of the insertion loss for single-scale wavelet trans-form processor of MSSW type is also given in the paper.When the output end of single-scale wavelet transform processor of MSSW type is connected to the amplifier,its insertion loss can be compensated.