The sensitivity of collinear nonlinear nondestructive testing technique based on harmonic detection is high,but the results are vulnerable to interference from other nonlinear of experiment sources,which leads to this...The sensitivity of collinear nonlinear nondestructive testing technique based on harmonic detection is high,but the results are vulnerable to interference from other nonlinear of experiment sources,which leads to this technology limited in industrial applications.To solve this problem,a non-collinear nonlinear ultrasonic testing experimental system is established based on non-collinear beam mixing technology.The non-collinear nonlinear response is observed in the steel and LY12 aluminum alloy.The results show that:1 Based on the benefits of space selection,mode conversion,frequency and steerable optional of non-collinear beam mixing technology,the interference of system nonlinear effects can be suppressed effectively;2 Mode conversion and beam mixing are present in steel and LY12 aluminum alloy,and the non-collinear non-linear response of LY12 aluminum alloy is stronger than steel and the measurement results are more obvious;3 The technology has the feasibility to evaluate the uniformity of material internal.展开更多
This paper proposes a novel nonlinear correlation filter for facial landmark localization. Firstly, we prove that SVM as a classifier can also be used for localization. Then, soft constrained Minimum Average Correlati...This paper proposes a novel nonlinear correlation filter for facial landmark localization. Firstly, we prove that SVM as a classifier can also be used for localization. Then, soft constrained Minimum Average Correlation Energy filter （soft constrained MACE） is proposed, which is more resistent to overfittings to training set than other variants of correlation filter. In order to improve the performance for the multi-mode of the targets, locally linear framework is introduced to our model, which results in Fourier Locally Linear Soft Constraint MACE （FL^2 SC-MACE）. Furthermore, we formulate the fast implementation and show that the time consumption in test process is independent of the number of training samples. The merits of our method include accurate localization performance, desiring generalization capability to the variance of objects, fast testing speed and insensitivity to parameter settings. We conduct the cross-set eye localization experiments on challenging FRGC, FERET and BioID datasets. Our method surpasses the state-of-arts especially in pixelwise accuracy.展开更多
This work presents an advanced mathematical tool applicable to the recognition and classification of power system transients and disturbances. Disturbances without a periodic pattern or with a non-linear pattern requi...This work presents an advanced mathematical tool applicable to the recognition and classification of power system transients and disturbances. Disturbances without a periodic pattern or with a non-linear pattern require a more suitable tool than the Fourier series （Fast Fourier or Windowed Fourier Transforms）. To overcome these drawbacks, other tools have been broadly used, such as the wavelet transform. However, the wavelet transform also has some drawbacks such as the lack of adaptivity or interpretation of nonlinear phenomena that the Hilbert and Hilbert Huang Transform techniques could mitigate. The Hilbert techniques transform a time domain function into a space representation both in time and frequency. In the paper, the technique is applied to analyse several short-term and steady events, like a short circuit, a capacitor-switching transient, or a line energisation, showing the abilities of the Hilbert-based transforms.展开更多
文摘The sensitivity of collinear nonlinear nondestructive testing technique based on harmonic detection is high,but the results are vulnerable to interference from other nonlinear of experiment sources,which leads to this technology limited in industrial applications.To solve this problem,a non-collinear nonlinear ultrasonic testing experimental system is established based on non-collinear beam mixing technology.The non-collinear nonlinear response is observed in the steel and LY12 aluminum alloy.The results show that:1 Based on the benefits of space selection,mode conversion,frequency and steerable optional of non-collinear beam mixing technology,the interference of system nonlinear effects can be suppressed effectively;2 Mode conversion and beam mixing are present in steel and LY12 aluminum alloy,and the non-collinear non-linear response of LY12 aluminum alloy is stronger than steel and the measurement results are more obvious;3 The technology has the feasibility to evaluate the uniformity of material internal.
文摘This paper proposes a novel nonlinear correlation filter for facial landmark localization. Firstly, we prove that SVM as a classifier can also be used for localization. Then, soft constrained Minimum Average Correlation Energy filter （soft constrained MACE） is proposed, which is more resistent to overfittings to training set than other variants of correlation filter. In order to improve the performance for the multi-mode of the targets, locally linear framework is introduced to our model, which results in Fourier Locally Linear Soft Constraint MACE （FL^2 SC-MACE）. Furthermore, we formulate the fast implementation and show that the time consumption in test process is independent of the number of training samples. The merits of our method include accurate localization performance, desiring generalization capability to the variance of objects, fast testing speed and insensitivity to parameter settings. We conduct the cross-set eye localization experiments on challenging FRGC, FERET and BioID datasets. Our method surpasses the state-of-arts especially in pixelwise accuracy.
文摘This work presents an advanced mathematical tool applicable to the recognition and classification of power system transients and disturbances. Disturbances without a periodic pattern or with a non-linear pattern require a more suitable tool than the Fourier series （Fast Fourier or Windowed Fourier Transforms）. To overcome these drawbacks, other tools have been broadly used, such as the wavelet transform. However, the wavelet transform also has some drawbacks such as the lack of adaptivity or interpretation of nonlinear phenomena that the Hilbert and Hilbert Huang Transform techniques could mitigate. The Hilbert techniques transform a time domain function into a space representation both in time and frequency. In the paper, the technique is applied to analyse several short-term and steady events, like a short circuit, a capacitor-switching transient, or a line energisation, showing the abilities of the Hilbert-based transforms.
