A novel text independent speaker identification system is proposed. In the proposed system, the 12-order perceptual linear predictive cepstrum and their delta coefficients in the span of five frames are extracted from...A novel text independent speaker identification system is proposed. In the proposed system, the 12-order perceptual linear predictive cepstrum and their delta coefficients in the span of five frames are extracted from the segmented speech based on the method of pitch synchronous analysis. The Fisher ratios of the original coefficients then be calculated, and the coefficients whose Fisher ratios are bigger are selected to form the 13-dimensional feature vectors of speaker. The Gaussian mixture model is used to model the speakers. The experimental results show that the identification accuracy of the proposed system is obviously better than that of the systems based on other conventional coefficients like the linear predictive cepstral coefficients and the Mel-frequency cepstral coefficients.展开更多
We have developed a multiplexed DNA detection method based on graphene oxide (GO) and molecular beacons (MBs) by synchronous fluorescence analysis, demonstrated it by an oligonucleotide sequence of wild-type HBV ...We have developed a multiplexed DNA detection method based on graphene oxide (GO) and molecular beacons (MBs) by synchronous fluorescence analysis, demonstrated it by an oligonucleotide sequence of wild-type HBV (T1) and a re- verse-transcription oligonucleotide sequence of the RNA fragment of HIV (T2) as a model system. In the absence of targets DNA, FAM-tagged free MB probes (PHBv) and ROX-tagged free MB probes (PHIv) are adsorbed on GO via π-π interactions between DNA nucleobases and nucleosides, and the π-rich GO brings the fluorophores of MB and GO into close proximity. And then, the fluorescence of fluorophores is quenched by GO. But in the presence of targets DNA, PHBV and PHW hybridize with their targets DNA resulting in the formation of double-stranded DNA (dsDNA), causing the separation of PHBV and PHW from the surface of GO and the recovery of the fluorescence of fluorophores (FAM and ROX) simultaneously. The simultane- ous detection of T1 and T2 can be realized by measuring fluorescence signals of FAM and ROX, respectively. Under the op- timum conditions, the fluorescence intensities of two dyes all exhibit good linear dependence on their target DNA concentra- tion in the range of 5×10-11-5×10 9 M. The detection limit of T1 is 3×10-11 M (3σ), and that of T2 is 2×10-11 M. Compared with other methods for DNA detection based on GO, the proposed method has some advantages including higher selectivity and shorter analytical time.展开更多
文摘A novel text independent speaker identification system is proposed. In the proposed system, the 12-order perceptual linear predictive cepstrum and their delta coefficients in the span of five frames are extracted from the segmented speech based on the method of pitch synchronous analysis. The Fisher ratios of the original coefficients then be calculated, and the coefficients whose Fisher ratios are bigger are selected to form the 13-dimensional feature vectors of speaker. The Gaussian mixture model is used to model the speakers. The experimental results show that the identification accuracy of the proposed system is obviously better than that of the systems based on other conventional coefficients like the linear predictive cepstral coefficients and the Mel-frequency cepstral coefficients.
文摘We have developed a multiplexed DNA detection method based on graphene oxide (GO) and molecular beacons (MBs) by synchronous fluorescence analysis, demonstrated it by an oligonucleotide sequence of wild-type HBV (T1) and a re- verse-transcription oligonucleotide sequence of the RNA fragment of HIV (T2) as a model system. In the absence of targets DNA, FAM-tagged free MB probes (PHBv) and ROX-tagged free MB probes (PHIv) are adsorbed on GO via π-π interactions between DNA nucleobases and nucleosides, and the π-rich GO brings the fluorophores of MB and GO into close proximity. And then, the fluorescence of fluorophores is quenched by GO. But in the presence of targets DNA, PHBV and PHW hybridize with their targets DNA resulting in the formation of double-stranded DNA (dsDNA), causing the separation of PHBV and PHW from the surface of GO and the recovery of the fluorescence of fluorophores (FAM and ROX) simultaneously. The simultane- ous detection of T1 and T2 can be realized by measuring fluorescence signals of FAM and ROX, respectively. Under the op- timum conditions, the fluorescence intensities of two dyes all exhibit good linear dependence on their target DNA concentra- tion in the range of 5×10-11-5×10 9 M. The detection limit of T1 is 3×10-11 M (3σ), and that of T2 is 2×10-11 M. Compared with other methods for DNA detection based on GO, the proposed method has some advantages including higher selectivity and shorter analytical time.