Directing to the weakness of the present fixed values mapping methods (method_F), a vocal tract system conversion method based on the universal background model (UBM) is proposed for improving the performance of t...Directing to the weakness of the present fixed values mapping methods (method_F), a vocal tract system conversion method based on the universal background model (UBM) is proposed for improving the performance of the speech conversion system from Chinese whis- pered speech to normal speech. For the numerous components of UBM, the errors produced by the acoustical probability density statistical model can't be ignored. Thus an effective Gaus- sian mixture components chosen method based on the posterior probability summation of the minimum spectral distortion is developed to optimizing the system performance. The proposed method (method_U) is analyzed and compared using the performance index (PI) based on Itakura-Saito spectral distortion measure. It is shown experimentally that the performance of method_U is more stability for different speakers and different phonemes than that of method_F. The average PI of method_U is better than method_F. It is shown that by selecting effective Gaussian mixture components, the PI of method_U can be further improved 5.11%. Subjective auditory tests also show that the proposed method can improve the definition and intelligibility of conversion speech.展开更多
AIM: To analyze the clinical factors influencing the human vision corrections via the changing of ocular components of human eye in various applications; and to analyze refractive state via a new effective axial leng...AIM: To analyze the clinical factors influencing the human vision corrections via the changing of ocular components of human eye in various applications; and to analyze refractive state via a new effective axial length.METHODS: An effective eye model was introduced by the ocular components of human eye including refractive indexes, surface radius(r1, r2, R1, R2) and thickness(t, T) of the cornea and lens, the anterior chamber depth(S1) and the vitreous length(S2). Gaussian optics was used to calculate the change rate of refractive error per unit amount of ocular components of a human eye(the rate function M). A new criterion of myopia was presented via an effective axial length.RESULTS: For typical corneal and lens power of 42 and 21.9 diopters, the rate function Mj(j=1 to 6) were calculated for a 1% change of r1, r2, R1, R2, t, T(in diopters) M1=+0.485, M2=-0.063, M3=+0.053, M4=+0.091, M5=+0.012, and M6=-0.021 diopters. For 1.0 mm increase of S1 and S2, the rate functions were M7=+1.35, and M8=-2.67 diopter/mm, respectively. These rate functions were used to analyze the clinical outcomes in various applications including laser in situ keratomileusis surgery, corneal cross linking procedure, femtosecond laser surgery and scleral ablation for accommodation.CONCLUSION: Using Gaussian optics, analytic formulas are presented for the change of refractive power due to various ocular parameter changes. These formulas provide useful clinical guidance in refractive surgery and other related procedures.展开更多
基金supported by the National Natural Science Foundation of China(61071215)the Science and Technology Foundation of Suzhou(SYG201033)the Pre-research Foundation of Soochow University(Q311901111,14317399)
文摘Directing to the weakness of the present fixed values mapping methods (method_F), a vocal tract system conversion method based on the universal background model (UBM) is proposed for improving the performance of the speech conversion system from Chinese whis- pered speech to normal speech. For the numerous components of UBM, the errors produced by the acoustical probability density statistical model can't be ignored. Thus an effective Gaus- sian mixture components chosen method based on the posterior probability summation of the minimum spectral distortion is developed to optimizing the system performance. The proposed method (method_U) is analyzed and compared using the performance index (PI) based on Itakura-Saito spectral distortion measure. It is shown experimentally that the performance of method_U is more stability for different speakers and different phonemes than that of method_F. The average PI of method_U is better than method_F. It is shown that by selecting effective Gaussian mixture components, the PI of method_U can be further improved 5.11%. Subjective auditory tests also show that the proposed method can improve the definition and intelligibility of conversion speech.
基金Supported by an Internal Research of New Vision Inc.,Taipei,Taiwan
文摘AIM: To analyze the clinical factors influencing the human vision corrections via the changing of ocular components of human eye in various applications; and to analyze refractive state via a new effective axial length.METHODS: An effective eye model was introduced by the ocular components of human eye including refractive indexes, surface radius(r1, r2, R1, R2) and thickness(t, T) of the cornea and lens, the anterior chamber depth(S1) and the vitreous length(S2). Gaussian optics was used to calculate the change rate of refractive error per unit amount of ocular components of a human eye(the rate function M). A new criterion of myopia was presented via an effective axial length.RESULTS: For typical corneal and lens power of 42 and 21.9 diopters, the rate function Mj(j=1 to 6) were calculated for a 1% change of r1, r2, R1, R2, t, T(in diopters) M1=+0.485, M2=-0.063, M3=+0.053, M4=+0.091, M5=+0.012, and M6=-0.021 diopters. For 1.0 mm increase of S1 and S2, the rate functions were M7=+1.35, and M8=-2.67 diopter/mm, respectively. These rate functions were used to analyze the clinical outcomes in various applications including laser in situ keratomileusis surgery, corneal cross linking procedure, femtosecond laser surgery and scleral ablation for accommodation.CONCLUSION: Using Gaussian optics, analytic formulas are presented for the change of refractive power due to various ocular parameter changes. These formulas provide useful clinical guidance in refractive surgery and other related procedures.