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基于谱相减改进算法的语音增强研究

铁道学报 2004年第1期26卷 64-67页

作者：徐岩杨静王维汉兰州交通大学信息与电气工程学院甘肃兰州730070

根据传统的谱相减增强型算法 ,提出了抑制噪声的谱减改进算法 ,暨根据带噪语音帧频谱功率与噪声帧频谱功率比值 ,动态调整α、β谱减系数 ,使之谱减效果在较大提高信噪比的同时 ,又能将残留的音乐噪声和语音失真保持在人耳听觉的容忍范... 详细信息

根据传统的谱相减增强型算法 ,提出了抑制噪声的谱减改进算法 ,暨根据带噪语音帧频谱功率与噪声帧频谱功率比值 ,动态调整α、β谱减系数 ,使之谱减效果在较大提高信噪比的同时 ,又能将残留的音乐噪声和语音失真保持在人耳听觉的容忍范围之内 ,保证原始语音信号质量达到一定的可懂度和清晰度。借助MATLAB语言进行试验仿真 ,仿真结果与原算法相比较。

关键词：语音增强谱相减算法噪声抑制

A Method for Head-shoulder Segmentation and Human Facial Feature Positioning

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通信学报 1998年第5期 29-34页

作者： Hu Tianjian Cai Dejun Department of electrical and information engineering (Huazhong university of Science and technology, Wuhan 430074)

ＡＭｅｔｈｏｄｆｏｒＨｅａｄｓｈｏｕｌｄｅｒＳｅｇｍｅｎｔａｔｉｏｎａｎｄＨｕｍａｎＦａｃｉａｌＦｅａｔｕｒｅＰｏｓｉｔｉｏｎｉｎｇＨｕＴｉａｎｊｉａｎＣａｉＤｅｊｕｎＤｅｐａｒｔｍｅｎｔｏｆＥｌｅｃｔｒｉｃａｌａ... 详细信息

ＡＭｅｔｈｏｄｆｏｒＨｅａｄｓｈｏｕｌｄｅｒＳｅｇｍｅｎｔａｔｉｏｎａｎｄＨｕｍａｎＦａｃｉａｌＦｅａｔｕｒｅＰｏｓｉｔｉｏｎｉｎｇＨｕＴｉａｎｊｉａｎＣａｉＤｅｊｕｎＤｅｐａｒｔｍｅｎｔｏｆＥｌｅｃｔｒｉｃａｌａｎｄＩｎｆｏｒｍａｔｉｏｎＥｎｇｉ...

关键词： model based image coding head shoulder segmentation facial feature extraction model adaptation edge detection.

Irregular wavelet frames on L^2 (R^n)

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Science china Mathematics 2005年第2期48卷 277-287页

作者： YANG Deyun & ZHOU Xingwei Department of information & technology, Nankai university, Tianjin 300071, china Department of Mathematics, Nankai university, Tianjin 300071, china Department of Computer Science, Taishan college, Taian 271000, china 1. Department of information & technology Nankai University 300071 Tianjin China 2. Department of Mathematics Nankai University 300071 Tianjin China 3. Department of Computer Science Taishan College 271000 Taian China

In this paper, we present the conditions on dilation parameter {sj}j that ensure a discrete irregular wavelet system to be a frame on L2(Rn), and for the wavelet frame we consider the perturbations of translation para... 详细信息

关键词： wavelet transform, frame, wavelet frame, irregular dilation.

A Sound Quality Objective Evaluation Method Based on Auditory Peripheral Simulation Model

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Journal of Bionic engineering 2010年第2期7卷 199-208页

作者： Yinhan Gao~1,Jun Xie~2,Jie Liang~1,Xin Chang~3,Baojun Wu~2 1.Experimental Centre of Testing Science,Jilin university,Changchun 130022,P.R.china 2.college of Instrumentation & electrical engineering,Jilin university,Changchun 130061,P.R.china 3.Laboratory of Applications and Computations in Electromagnetics and Optics,Department of electrical engineering, university of Washington,WA 98195-2500,USA [a] Experimental Centre of Testing Science Jilin University Changchun 130022 P. R. China [b] College of Instrumentation & Electrical Engineering Jilin University Changchun 130061 P. R. China [c] Laboratory of Applications Computations in Electromagnetics Optics Department of Electrical Engineering University of Washington WA 98195-2500 USA

Based on auditory peripheral simulation model, a new Sound Quality Objective Evaluation (SQOE) method is presented,which can be used to model and analyze the impacts of head, shoulder and other parts of human body on sound wave *** method employs the artificial head technique, in which the head related transfer function was taken into account tothe outer ear simulation ***, a bionic artificial head was designed as the outer ear model with considering the outersound field in view of theory and physical *** the auditory peripheral simulation model was built, which mimicsthe physiological functions of the human hearing, simulating the acoustic signal transfer process and conversion mechanismsfrom the free field to the peripheral auditory ***, performance comparison was made between the proposed SQOEmethod and ArtemiS software, and the verifications of subjective and objective related analysis were *** show thatthe proposed method was economical, simple, and with good evaluation quality.

关键词： sound quality objective evaluation auditory peripheral simulation model artificial head head related transfer function

A circular zone partition method for identifying Duffing oscillator state transition and its application to BPSK signal demodulation

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Science china(information Sciences) 2011年第6期54卷 1274-1282页

作者： FU YongQing 1 , WU DongMei 1 , ZHANG Lin 2 & LI XingYuan 1 1 college of information and Communication engineering, Harbin engineering university, Harbin 150001, china 2 college of Underwater Acoustic engineering, Harbin engineering university, Harbin 150001, china 1. college of information and Communication engineering Harbin Engineering University Harbin 150001 China2. College of Underwater Acoustic Engineering Harbin Engineering University Harbin 150001 China

When a Duffing oscillator is applied to signal detection, identifying its state transition is indispensable. Due to lack of an effective method for automatically distinguishing the state transition, phase analysis is extensively used. However, it needs ocular estimation to identify phase pattern corresponding to transition of Duffing oscillator. Hence it is not fit for communication signal demodulation. To solve the problem, this paper proposes a method, called circular zone partition (CZP), for partitioning trajectory on the phase plane of Duffing oscillator. First, a computing model for Duffing oscillator is described. Then, the fundamental principle and algorithm for the CZP method are discussed. Meanwhile the equation of a circular zone divider and its realization are presented. Thus, by way of the divider, the two-dimensional phase trajectory pattern of Duffing oscillator driven by an external signal can be transformed into the one-dimensional time signal, whose envelop after being filtered is able to indicate the state transition, i.e. the presence or the absence of external signal. Finally, to verify the effect of the CZP method on binary phase shifted keying (BPSK) signal demodulation, two examples are presented and simulation results show that this CZP method is accurate and valid for BPSK signal demodulation.

关键词： chaos nonlinear oscillators signal detection digital communication receivers

The Detection of Defects in Optical Fibers Using a Hybrid Opto-electronic Correlator

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Chinese Journal of Lasers 2000年第3期9卷 15-21页

作者： LIU Yange LIU Wei ZHANG Yimo ZHOU Ge (college of Precision Instrument and Opto-electronics engineering, Tianjin university Opto-electronic information Science and technology Lab., Tianjin 300072, china) 天津大学光电信息技术科学开放实验室天津

A hybrid opto-electronic correlator for detecting defects i n optical fibers is proposed. After the light from a He-Ne laser being expanded and filtered it is not collimated but directly passes a Fourier transform lens and illuminates a reference fiber and a test fiber at the same input plane. The Fourier transform spectrum of the two fibers is therefore obtained at the rear focal plane of the lens, where it is sampled via a CCD array connected with a computer through a frame grabber. The computer performs filter, inverse Fourier transform and setting threshold operation on classification. The system is an equivalent of joint transform correlator with a Fourier lens of long focal length. The experiment results for optical fibers having incoordinate defects are presented. The results indicate that the system can be used for fiber defect detection, and has the advantages of high identification, compact configuration, easy adjustment and flexible manipulation.

关键词： joint transform correlation Fourier transform optical fiber defect detection

SYSTEM IDENTIFICATION USING DYNAMIC GA BASED ON NUMERIC ENCODING

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Journal of Central South university 1997年第2期9卷 128-131页

作者： Yu Shouyi Peng Ying Zheng Xiaoming (college of information engineering, Central South university of technology, Changsha 410083, china) college of information engineering Central South University of Technology Changsha 410083 China

A dynamic genetic algorithms based on numeric encoding is proposed and its application in system identification is discussed. Simulation shows that the introduction of both numeric encoding and dynamic mutation can effectively improve the accuracy and speed of searching for the optimum. It also show that the improved Genetic algorithm can identify time delay and parameters of the plant at the same time and converge to globle optimization.

关键词： genetic algorithms dynamic mutation operator system identification

Delay-dependent robust H∞ control for uncertain fuzzy hyperbolic systems with multiple delays

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Progress in Natural Science:Materials International 2008年第1期18卷 97-104页

作者： Huaguang Zhanga ,*,Qingxian Gong a,b ,Yingchun Wang a aSchool of information Science and engineering,Northeastern university,Shenyang 110004,china bDepartment of electrical engineering,Changchun Institute of technology,Changchun 130012,china School of information Science and engineering Northeastern University Shenyang 110004 China Department of electrical engineering Changchun Institute of Technology Changchun 130012 China

The robust H∞ control problem was considered for a class of fuzzy hyperbolic model(FHM)systems with parametric uncertainties and multiple ***,FHM modeling method was presented for time-delay nonlinear ***,by using Lyapunov–Krasov- skii approaches,delay-dependent suficient condition for the existence of a kind of state feedback controller was proposed,which was expressed as linear matrix inequalities(LMIs).The controller can guarantee that the resulting closed-loop system is robustly asymptot- ically stable with a prescribed H∞ performance level for all admissible uncertainties and ***,a simulation example was provided to illustrate the effectiveness of the proposed approach.

关键词： Fuzzy hyperbolic model Robust H1 control Asymptotical stability Linear matrix inequality Uncertain time-delay system

Medical image segmentation using improved FCM

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Science china(information Sciences) 2012年第5期55卷 1052-1061页

作者： ZHANG XiaoFeng 1,2,ZHANG CaiMing 1,3,4,TANG WenJing 1,2 & WEI ZhenWen 1 1 School of Computer Science and technology,Shandong university,Jinan 250101,china 2 School of information and electrical engineering,Ludong university,Yantai 264025,china 3 School of Computer Science and technology,Shandong university of Finance and Economics,Jinan 250014,china 4 Shandong Province Key Lab of Digital Media technology,Jinan 250014,china 1. School of Computer Science and technology Shandong University Jinan 250101 China2. School of Information and Electrical Engineering Ludong University Yantai 264025 China3. School of Computer Science and Technology Shandong University of Finance and Economics Jinan 250014 China4. Shandong Province Key Lab of Digital Media Technology Jinan 250014 China

Image segmentation is one of the most important problems in medical image processing,and the existence of partial volume effect and other phenomena makes the problem much more *** C-means,as an effective tool to deal with PVE,however,is faced with great challenges in *** at this,this paper proposes one improved FCM algorithm based on the histogram of the given image,which will be denoted as HisFCM and divided into two *** first phase will retrieve several intervals on which to compute cluster centroids,and the second one will perform image segmentation based on improved FCM *** with FCM and other improved algorithms,HisFCM is of much higher efficiency with satisfying *** on medical images show that HisFCM can achieve good segmentation results in less than 0.1 second,and can satisfy real-time requirements of medical image processing.

关键词： FCM histogram image segmentation medical image processing