Investigated in this paper is the generalized nonlinear Schrdinger equation with radial symmetry.Withthe help of symbolic computation, the one-, two-, and N-soliton solutions are obtained through the bilinear metho...Investigated in this paper is the generalized nonlinear Schrdinger equation with radial symmetry.Withthe help of symbolic computation, the one-, two-, and N-soliton solutions are obtained through the bilinear method.Bcklund transformation in the bilinear form is presented, through which a new solution is constructed.Graphically, wehave found that the solitons are symmetric about x=0, while the soliton pulse width and amplitude will change alongwith the distance and time during the propagation.展开更多
A method of conversion from whispered speech to normal speech using the extended bilinear transformation was proposed. On account of the different deviation degrees of the whisper's formants in different frequency ba...A method of conversion from whispered speech to normal speech using the extended bilinear transformation was proposed. On account of the different deviation degrees of the whisper's formants in different frequency bands, the spectrum of the whispered speech will be processed in the separate partitions of this paper. On the basis of this spectrum, we will establish a conversion function able to usefully convert whispered speech to normal speech. Because of the whisper's non-linear offset in relation to normal speech, this paper introduces an expansion factor in the bilinear transform function making it correspond more closely to the actual conversion demands of whispered speech to normal speech. The introduction of this factor takes the non-linear move of the spectrum and the compression of the formant bandwidth into consideration, thus effectively reducing the spectrum distortion distance in the conversion. The experiment results show that the conversion presented in this paper effectively improves both the sound quality and the intelligibility of whispered speech.展开更多
We present a systematic procedure to derive discrete analogues of integrable PDEs via Hirota’s bilinear method.This approach is mainly based on the compatibility between an integrable system and its B¨acklund tr...We present a systematic procedure to derive discrete analogues of integrable PDEs via Hirota’s bilinear method.This approach is mainly based on the compatibility between an integrable system and its B¨acklund transformation.We apply this procedure to several equations,including the extended Korteweg-deVries(Kd V)equation,the extended Kadomtsev-Petviashvili(KP)equation,the extended Boussinesq equation,the extended Sawada-Kotera(SK)equation and the extended Ito equation,and obtain their associated semidiscrete analogues.In the continuum limit,these differential-difference systems converge to their corresponding smooth equations.For these new integrable systems,their B¨acklund transformations and Lax pairs are derived.展开更多
为解决传统印刷品图像配准算法精度和速度不能兼得的问题,本文提出了一种基于外轮廓与霍夫变换的印刷品图像配准算法。该算法先对图像进行灰度化、去噪、对比度增强、图像分割完成图像预处理;根据图像分割结果获得印刷区域的外轮廓,计...为解决传统印刷品图像配准算法精度和速度不能兼得的问题,本文提出了一种基于外轮廓与霍夫变换的印刷品图像配准算法。该算法先对图像进行灰度化、去噪、对比度增强、图像分割完成图像预处理;根据图像分割结果获得印刷区域的外轮廓,计算外轮廓形心坐标,得到偏移量,再根据轮廓计算出旋转量;根据偏移量和旋转量对待配准图像进行刚性变换和双线性插值完成图像粗配准;在感兴趣区域(Region of interest,ROI)中限制霍夫变换的动态参数,计算出ROI中的直线,根据直线交点得到3个坐标,根据3个坐标对待配准图像进行仿射变换和双线性插值,完成图像精配准。实验验证表明,本算法配准结果的平均NNC系数达到0.903264,平均配准时间为256.91。展开更多
基金Supported by the National Natural Science Foundation of China under Grant No.60772023the Open Fund (No.BUAASKLSDE-09KF-04)+2 种基金Supported Project (No.SKLSDE-2010ZX-07) of the State Key Laboratory of Software Development Environment,Beijing University of Aeronautics and Astronauticsthe National Basic Research Program of China (973 Program) under Grant No.2005CB321901the Specialized Research Fund for the Doctoral Program of Higher Education under Grant No.200800130006,Chinese Ministry of Education
文摘Investigated in this paper is the generalized nonlinear Schrdinger equation with radial symmetry.Withthe help of symbolic computation, the one-, two-, and N-soliton solutions are obtained through the bilinear method.Bcklund transformation in the bilinear form is presented, through which a new solution is constructed.Graphically, wehave found that the solitons are symmetric about x=0, while the soliton pulse width and amplitude will change alongwith the distance and time during the propagation.
基金supported by the National Natural Science Foundation of China(61271359,61071215)Suzhou Science and Technology Development Plan(SYG201001)Key Joint Laboratory of Soochow University and JieMei Biomedical Engineering Instrument
文摘A method of conversion from whispered speech to normal speech using the extended bilinear transformation was proposed. On account of the different deviation degrees of the whisper's formants in different frequency bands, the spectrum of the whispered speech will be processed in the separate partitions of this paper. On the basis of this spectrum, we will establish a conversion function able to usefully convert whispered speech to normal speech. Because of the whisper's non-linear offset in relation to normal speech, this paper introduces an expansion factor in the bilinear transform function making it correspond more closely to the actual conversion demands of whispered speech to normal speech. The introduction of this factor takes the non-linear move of the spectrum and the compression of the formant bandwidth into consideration, thus effectively reducing the spectrum distortion distance in the conversion. The experiment results show that the conversion presented in this paper effectively improves both the sound quality and the intelligibility of whispered speech.
基金supported by National Natural Science Foundation of China(Grant Nos.11331008 and 11201425)the Hong Kong Baptist University Faculty Research(Grant No.FRG2/11-12/065)the Hong Kong Research Grant Council(Grant No.GRF HKBU202512)
文摘We present a systematic procedure to derive discrete analogues of integrable PDEs via Hirota’s bilinear method.This approach is mainly based on the compatibility between an integrable system and its B¨acklund transformation.We apply this procedure to several equations,including the extended Korteweg-deVries(Kd V)equation,the extended Kadomtsev-Petviashvili(KP)equation,the extended Boussinesq equation,the extended Sawada-Kotera(SK)equation and the extended Ito equation,and obtain their associated semidiscrete analogues.In the continuum limit,these differential-difference systems converge to their corresponding smooth equations.For these new integrable systems,their B¨acklund transformations and Lax pairs are derived.
文摘为解决传统印刷品图像配准算法精度和速度不能兼得的问题,本文提出了一种基于外轮廓与霍夫变换的印刷品图像配准算法。该算法先对图像进行灰度化、去噪、对比度增强、图像分割完成图像预处理;根据图像分割结果获得印刷区域的外轮廓,计算外轮廓形心坐标,得到偏移量,再根据轮廓计算出旋转量;根据偏移量和旋转量对待配准图像进行刚性变换和双线性插值完成图像粗配准;在感兴趣区域(Region of interest,ROI)中限制霍夫变换的动态参数,计算出ROI中的直线,根据直线交点得到3个坐标,根据3个坐标对待配准图像进行仿射变换和双线性插值,完成图像精配准。实验验证表明,本算法配准结果的平均NNC系数达到0.903264,平均配准时间为256.91。