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Analysis of Stability and Large Deflection Buckle of Rolled Strip by Third Power B-Spline Function Method
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作者 Bian Yuhong 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 1997年第2期24-28,共5页
A new method——the third power B-spline function method is developed to analyse the stability and the buckle of rolled strip under residual stress.The large deflection theory of thin plate is used to calculate the bu... A new method——the third power B-spline function method is developed to analyse the stability and the buckle of rolled strip under residual stress.The large deflection theory of thin plate is used to calculate the buckle of rolled strip and criterion of critical buckle is given.The computed results tally with those of experiment well,which provides theoretical basis and method for developing the mathematical model of flatness control. 展开更多
关键词 flatness control large deflection buckle critical buckle third power b-spline function
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Numerical Solution of Functional Integral and Integro-Differential Equations by Using B-Splines
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作者 Hesam-Eldien Derili Gherjalar Hossein Mohammadikia 《Applied Mathematics》 2012年第12期1940-1944,共5页
This paper describes an approximating solution, based on Lagrange interpolation and spline functions, to treat functional integral equations of Fredholm type and Volterra type. This method extended to functional integ... This paper describes an approximating solution, based on Lagrange interpolation and spline functions, to treat functional integral equations of Fredholm type and Volterra type. This method extended to functional integral and integro-differential equations. For showing efficiency of the method we give some numerical examples. 展开更多
关键词 LAGRANGE Interpolation b-spline functions functionAL Integral EQUATION functionAL Integro-Differential EQUATION functionAL Differential EQUATION
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The Investigation and Study of Hydrogen Atom in Spherical Cavity Using B-Spline Basis Functions: A Mathematical Approach
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作者 Alireza Heidari Foad Khademi Jahromi +1 位作者 Roozbeh Amiri Mohammadali Ghorbani 《Journal of Modern Physics》 2012年第4期334-339,共6页
The following article has been retracted due to the investigation of complaints received against it. The Editorial Board found that substantial portions of the text came from other published papers. The scientific com... The following article has been retracted due to the investigation of complaints received against it. The Editorial Board found that substantial portions of the text came from other published papers. The scientific community takes a very strong view on this matter, and the Health treats all unethical behavior such as plagiarism seriously. This paper published in Vol.3 No. 4, 334-339, 2012, has been removed from this site. 展开更多
关键词 Hydrogen ATOM Spherical Cavity b-spline basis functionS Quantum Systems Nanoscience VARIATIONAL Method Wave functionS b-splines’ Properties
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B-Spline高阶元方法在三维水弹性力学中的应用 被引量:4
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作者 杜双兴 殷学文 李琪华 《船舶力学》 EI 2000年第1期17-23,共7页
本文简要叙述了B-Spline样条函数的基本性质;将二元高阶B-Spline函数与Galerkin方法相结合,形成了任意光滑空间曲面的二元高阶 B- Spline函数簇解析表达方法; 讨论了 B- Spline函数在三维水... 本文简要叙述了B-Spline样条函数的基本性质;将二元高阶B-Spline函数与Galerkin方法相结合,形成了任意光滑空间曲面的二元高阶 B- Spline函数簇解析表达方法; 讨论了 B- Spline函数在三维水弹性力学边界积分方程中应用的一些数值计算问题。 展开更多
关键词 b-spline函数 高阶元 水弹性力学
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B-Spline函数在区域三维地下速度模型中的应用 被引量:1
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作者 解廷伟 赵伯明 《山西建筑》 2008年第8期118-119,共2页
基于B-Spline函数对大宗散乱数据的处理方法,将B-Spline函数应用到地震数值计算的物理模型中,优化了物理模型,使数值计算的稳定性及计算结果的准确性得以保证。
关键词 散乱数据 地震数值计算 区域三维地下速度结构模型 b-spline函数
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二次B-Spline时域基函数的TDFEM的应用
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作者 吴霞 周乐柱 《哈尔滨工业大学学报》 EI CAS CSCD 北大核心 2010年第5期836-840,共5页
提出了时域有限元法(TDFEM)的一种新的基函数—二次B-spline时域基函数.首先简述了时域有限元法的原理和基本公式;然后提出了新型的基于B-spline函数的条件稳定和无条件稳定的时域有限元法方案,并应用于三维电磁辐射问题.通过典型的算... 提出了时域有限元法(TDFEM)的一种新的基函数—二次B-spline时域基函数.首先简述了时域有限元法的原理和基本公式;然后提出了新型的基于B-spline函数的条件稳定和无条件稳定的时域有限元法方案,并应用于三维电磁辐射问题.通过典型的算例对这两种方案的精度、运算时间进行了比较,证实了基于二次B-spline函数的时域有限元法的有效性.通过稳定性理论分析得出该算法的精确稳定性,并且通过数值计算的结果得到验证. 展开更多
关键词 时域有限元法 二次b-spline时域基函数 电磁辐射 无条件稳定 超宽带
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B-Spline函数的自适应网络模糊推理系统
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作者 方千山 《华侨大学学报(自然科学版)》 CAS 2003年第4期358-363,共6页
提出基于 B- Spline函数条件的自适应网络模糊推理系统 (B- ANFIS) ,该系统将 B- Spline和ANFIS两者有机地结合在一起 ,取长补短以达到简捷的隶属函数自寻优 .研究结果表明 ,该运算的速度快、系统的逼近误差小、精度高、简单、易行 。
关键词 bspline函数 自适应网络模糊推理系统 b—ANFIS 隶属函数 逼近误差 模糊控制
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基于观测数据的地表太阳形状B-样条函数模型
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作者 沈童 赵乐 冯结青 《计算机科学》 CSCD 北大核心 2024年第1期215-224,共10页
描述地面上接收太阳辐射能分布的函数被称为地表太阳形状模型。它对塔式光热太阳能发电中接收器上辐射能密度分布的精确仿真至关重要。光晕辐射能占太阳辐射总能量的百分比,也被称为光晕辐射能占比(CircumSolar Ratio,CSR),它是地表太... 描述地面上接收太阳辐射能分布的函数被称为地表太阳形状模型。它对塔式光热太阳能发电中接收器上辐射能密度分布的精确仿真至关重要。光晕辐射能占太阳辐射总能量的百分比,也被称为光晕辐射能占比(CircumSolar Ratio,CSR),它是地表太阳形状模型中的一个重要参数。目前,常用的地表太阳形状模型普遍存在精度不高、计算所得CSR无法与输入CSR对齐、辐射能分布不连续、模型函数不能解析积分等不足。针对这些问题,文中提出了基于观测数据拟合的地表太阳形状张量积B-样条函数模型。首先,对两个观测数据集进行数据清洗、去噪、归一化、分组平均和拼接,得到具有不同CSR值、随入射角度偏移θ变化的84组太阳辐射能扫描剖面数据;其次,选择变化最剧烈的CSR为0.005这组数据,以θ为自变量,进行带约束的B-样条函数拟合(二次规划问题),拟合过程中,通过差分进化算法优化节点向量,并通过实验确定最优控制系数的数量;然后,采用上述节点向量、控制系数数量,以相同的方式拟合其他CSR值的83组数据;最后,将所得84个单变量B-样条函数模型作为输入,以CSR为自变量对其控制系数进行拟合,并类似地确定节点向量和控制系数数目,最终得到以CSR和θ为自变量、具有12×15个控制系数的张量积B-样条函数模型,即地表太阳形状模型。与已有模型相比,该B-样条函数模型是一个C2光滑的模型,具有CSR对齐、拟合精度高和辐射能分布可解析积分的优点。 展开更多
关键词 太阳形状模型 CSR对齐 b-样条函数拟合 二次规划 差分进化算法
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SOME SHAPE-PRESERVING QUASI-INTERPOLANTS TO NON-UNIFORMLY DISTRIBUTED DATA BY MQ-B-SPLINES 被引量:8
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作者 ZhangWeixiang WuZongmin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2004年第2期191-202,共12页
Based on the definition of MQ-B-Splines,this article constructs five types of univariate quasi-interpolants to non-uniformly distributed data. The error estimates and the shape-preserving properties are shown in detai... Based on the definition of MQ-B-Splines,this article constructs five types of univariate quasi-interpolants to non-uniformly distributed data. The error estimates and the shape-preserving properties are shown in details.And examples are shown to demonstrate the capacity of the quasi-interpolants for curve representation. 展开更多
关键词 scattered data fitting QUASI-INTERPOLATION shape-preserving approximation radial basis function MQ-b-splines.
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Linearized Controller Design for the Output Probability Density Functions of Non-Gaussian Stochastic Systems 被引量:1
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作者 Pousga Kabore Husam Baki 《International Journal of Automation and computing》 EI 2005年第1期67-74,共8页
This paper presents a linearized approach for the controller design of the shape of output probability density functions for general stochastic systems. A square root approximation to an output probability density fun... This paper presents a linearized approach for the controller design of the shape of output probability density functions for general stochastic systems. A square root approximation to an output probability density function is realized by a set of B-spline functions. This generally produces a nonlinear state space model for the weights of the B-spline approximation. A linearized model is therefore obtained and embedded into a performance function that measures the tracking error of the output probability density function with respect to a given distribution. By using this performance function as a Lyapunov function for the closed loop system, a feedback control input has been obtained which guarantees closed loop stability and realizes perfect tracking. The algorithm described in this paper has been tested on a simulated example and desired results have been achieved. 展开更多
关键词 Dynamic stochastic systems probability density function b splines neural networks Lyapunov stability theory
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Wavelet-Based Fractal Function Approximation 被引量:1
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作者 Zhang Hejei Tao Ran Zhou Siyong & Wang Yue(Department of Electronic Engineering, Beijing Institute of Technology, 100081, P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1999年第4期60-66,共7页
In this paper, we study on the application of radical B-spline wavelet scaling function in fractal function approximation system. The paper proposes a wavelet-based fractal function approximation algorithm in which th... In this paper, we study on the application of radical B-spline wavelet scaling function in fractal function approximation system. The paper proposes a wavelet-based fractal function approximation algorithm in which the coefficients can be determined by solving a convex quadraticprogramming problem. And the experiment result shows that the approximation error of this algorithm is smaller than that of the polynomial-based fractal function approximation. This newalgorithm exploits the consistency between fractal and scaling function in multi-scale and multiresolution, has a better approximation effect and high potential in data compression, especially inimage compression. 展开更多
关键词 b-spline Wavelet scaling function Fractal function APPROXIMATION Quadratic programming.
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基于B-Spline的位移监测数据动态优化拟合
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作者 卫俊杰 荣建 +1 位作者 王颖轶 王美华 《建筑施工》 2023年第12期2365-2369,共5页
为更好地进行工程位移的监测,对基坑施工过程钢支撑水平位移激光监测数据特征、误差类型及其成因进行了分析,研究了B-Spline在海量监测数据去噪中的适用性,并通过引入待估参数的B样条基函数修正,建立最小二乘控制下位移-时间关系的高精... 为更好地进行工程位移的监测,对基坑施工过程钢支撑水平位移激光监测数据特征、误差类型及其成因进行了分析,研究了B-Spline在海量监测数据去噪中的适用性,并通过引入待估参数的B样条基函数修正,建立最小二乘控制下位移-时间关系的高精度拟合优化。结果表明:待估参数ζ_(i)的修正重构,把监测数据序列转化为参数估计问题,使位移时变关系的最优化拟合成为可能;移动时间坐标方法,可实现等时距监测数据的动态处理,优化计算时间;B-Spline融合最小二乘法,在最小方差控制下实现监测数据-时间关系最优拟合,形成光滑、连续的高精度拟合曲线,有利于提高监测反馈控制的精度和可靠性。实例应用验证了成果的可靠性和适用性。 展开更多
关键词 基坑位移 误差处理 b样条基函数修正重构 b-spline融合最小二乘法 高精度拟合
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Septic B-Spline Solution of Fifth-Order Boundary Value Problems
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作者 Bin Lin 《Journal of Applied Mathematics and Physics》 2016年第8期1446-1454,共9页
A numerical method based on septic B-spline function is presented for the solution of linear and nonlinear fifth-order boundary value problems. The method is fourth order convergent. We use the quesilinearization tech... A numerical method based on septic B-spline function is presented for the solution of linear and nonlinear fifth-order boundary value problems. The method is fourth order convergent. We use the quesilinearization technique to reduce the nonlinear problems to linear problems and use B-spline collocation method, which leads to a seven nonzero bands linear system. Illustrative example is included to demonstrate the validity and applicability of the proposed techniques. 展开更多
关键词 Septic b-spline function Fifth-Order boundary Value Problems b-spline Collocation Method Nonlinear Problems
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B-Spline Collocation Method for Solving Singularly Perturbed Boundary Value Problems
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作者 Bin Lin 《Journal of Applied Mathematics and Physics》 2016年第9期1699-1704,共6页
We use fifth order B-spline functions to construct the numerical method for solving singularly perturbed boundary value problems. We use B-spline collocation method, which leads to a tri-diagonal linear system. The ac... We use fifth order B-spline functions to construct the numerical method for solving singularly perturbed boundary value problems. We use B-spline collocation method, which leads to a tri-diagonal linear system. The accuracy of the proposed method is demonstrated by test problems. The numerical results are found in good agreement with exact solutions. 展开更多
关键词 Fifth Order b-spline functions b-spline Collocation Method Singularly Perturbed boundary Value Problems
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Numerical Solution of the Seventh Order Boundary Value Problems Using B-Spline Method
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作者 Maryam Khazaei Yeganeh Karamipour 《Journal of Applied Mathematics and Physics》 2021年第12期3058-3066,共9页
We develop a numerical method for solving the boundary value problem of The Linear Seventh Ordinary Boundary Value Problem by using the seventh-degree B-Spline function. Formulation is based on particular terms of ord... We develop a numerical method for solving the boundary value problem of The Linear Seventh Ordinary Boundary Value Problem by using the seventh-degree B-Spline function. Formulation is based on particular terms of order of seventh order boundary value problem. We obtain Septic B-Spline formulation and the Collocation B-spline method is formulated as an approximation solution. We apply the presented method to solve an example of seventh order boundary value problem in which the result shows that there is an agreement between approximate solutions and exact solutions. Resulting in low absolute errors shows that the presented numerical method is effective for solving high order boundary value problems. Finally, a general conclusion has been included. 展开更多
关键词 spline and b-spline functions Seventh Order boundary Value Problem Septic b-spline Collocation Method
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Effects of interferon α-2b on liver function, complement level and oxidative stress in patients with hepatitis B
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作者 Li Li Jie Qiu Hua-Li Wang 《Journal of Hainan Medical University》 2019年第15期35-38,共4页
Objective:To observe the effect of interferonα-2b treatment on liver function,liver fibrosis,complement protein and oxidative stress in patients with hepatitis B.Methods:A total of 100 patients with hepatitis B in ou... Objective:To observe the effect of interferonα-2b treatment on liver function,liver fibrosis,complement protein and oxidative stress in patients with hepatitis B.Methods:A total of 100 patients with hepatitis B in our hospital were randomly divided into the control group and the observation group,with 50 cases in each group.After admission,patients in the control group were treated with entecavir,while patients in the observation group were treated with interferonα-2b combined with entecavir.The levels of serum total bilirubin(TBil),aspartate aminotransferase(AST),alanine aminotransferase(ALT),type III procollagen(PCIII),type IV collagen(CIV),complement C3 protein(C3),complement C4 protein(C4),malondialdehyde(MDA),superoxide dismutase(SOD)and nitric oxide(NO)were compared between the two groups before and after treatment.Results:After treatment,the levels of TBil,AST,ALT,PCIII,CIV,MDA and NO in serum of patients with hepatitis B in both groups were significantly lower than those before treatment,and the levels of C3,C4 and SOD were significantly higher than those before treatment(P<0.05).After treatment,the levels of TBil,AST,ALT,PC III,C IV,MDA and NO in serum of patients in the observation group were significantly lower than those in the control group,while the levels of C3,C4 and SOD in serum of patients in the observation group were significantly higher than those in the control group(P<0.05).Conclusions:The combination of interferonα-2b and entecavir has a good curative effect on hepatitis B.It can significantly improve the liver function and immune function of patients,delay the process of liver fibrosis and reduce oxidative stress injury.It is worthy of clinical promotion. 展开更多
关键词 Interferonα-2b ENTECAVIR HEPATITIS b Liver function COMPLEMENT protein OXIDATIVE stress
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The G^3 spline basis functions
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作者 Diao Luhong Cao Huan +1 位作者 Zhang Zhenmeng Lu Xiaoyan 《Computer Aided Drafting,Design and Manufacturing》 2016年第1期41-46,共6页
The explicit expression of the G3 basis function is presented in this paper. It is derived by constructing the conversion matrix between G3 basis function and Brzier representation. After the matrix decomposition, equ... The explicit expression of the G3 basis function is presented in this paper. It is derived by constructing the conversion matrix between G3 basis function and Brzier representation. After the matrix decomposition, equations for constructing G3 splines can be presented independently of geometric shape parameters' values. It makes the equation's solving easier. It is also known that the general form of the G3spline basis function is given in the first time. Its geometric construction method is presented. 展开更多
关键词 geometric continuity G3 spline basis functions splines b6zier representation matrix decomposition
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Analysis of a Gyroscope′s Rotor Nonlinear Supported Magnetic Field Based on the B-Spline Wavelet-FEM
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作者 LIU Jian-feng YUAN Gan-nan +1 位作者 HUANG Xu YU Li 《International Journal of Plant Engineering and Management》 2005年第3期152-159,共8页
A supported framework of a gyroscope's rotor is designed and the B-Spline wavelet finite element model of nonlinear supported magnetic field is worked out. A new finite element space is studied in which the scaling f... A supported framework of a gyroscope's rotor is designed and the B-Spline wavelet finite element model of nonlinear supported magnetic field is worked out. A new finite element space is studied in which the scaling function of the B-spline wavelet is considered as the shape function of a tetrahedton. The magnetic field is spited by an artificial absorbing body which used the condition of field radiating, so the solution is unique. The resolution is improved via the varying gradient of the B-spline function under the condition of unchanging gridding. So there are some advantages in dealing with the focus flux and a high varying gradient result from a nonlinear magnetic field. The result is more practical. Plots of flux and in the space is studied via simulating the supported system model. The results of the study are useful in the research of the supported magnetic system for the gyroscope rotor. 展开更多
关键词 nonlinear supported magnetic field b-spline wavelet FEM GYROSCOPE interpolation basis function boundary condition
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Knot Insertion Algorithms for ECT B-spline Curves
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作者 SONG Huan-huan TANG Yue-hong LI Yu-juan 《Computer Aided Drafting,Design and Manufacturing》 2013年第2期29-35,共7页
Knot insertion algorithm is one of the most important technologies of B-spline method. By inserting a knot the local prop- erties of B-spline curve and the control flexibility of its shape can be fiu'ther improved, a... Knot insertion algorithm is one of the most important technologies of B-spline method. By inserting a knot the local prop- erties of B-spline curve and the control flexibility of its shape can be fiu'ther improved, also the segmentation of the curve can be rea- lized. ECT spline curve is drew by the multi-knots spline curve with associated matrix in ECT spline space; Muehlbach G and Tang Y and many others have deduced the existence and uniqueness of the ECT spline function and developed many of its important properties .This paper mainly focuses on the knot insertion algorithm of ECT B-spline curve.It is the widest popularization of B-spline Behm algorithm and theory. Inspired by the Behm algorithm, in the ECT spline space, structure of generalized P61ya poly- nomials and generalized de Boor Fix dual functional, expressing new control points which are inserted after the knot by linear com- bination of original control vertex the single knot, and there are two cases, one is the single knot, the other is the double knot. Then finally comes the insertion algorithm of ECT spline curve knot. By application of the knot insertion algorithm, this paper also gives out the knot insertion algorithm of four order geometric continuous piecewise polynomial B-spline and algebraic trigonometric spline B-spline, which is consistent with previous results. 展开更多
关键词 ECT b-splines knot insertion geometric continuity generalized P61ya polynomial generalized de boor-Fix functional
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根据时-频分辨特性的B样条双正交小波的选择 被引量:4
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作者 张义荣 鲜明 肖顺平 《计算机学报》 EI CSCD 北大核心 2002年第4期430-437,共8页
该文简要地分析了在基于小波变换的图像和视频编码中小波基的选择对编码效率和编码质量的影响 .从适于提取图像和视频信号高频成分的角度 ,提出了根据时 -频分辨特性对 B样条双正交小波进行选择的标准 .给出了 B样条小波的构造过程和计... 该文简要地分析了在基于小波变换的图像和视频编码中小波基的选择对编码效率和编码质量的影响 .从适于提取图像和视频信号高频成分的角度 ,提出了根据时 -频分辨特性对 B样条双正交小波进行选择的标准 .给出了 B样条小波的构造过程和计算时 -频窗面积的方法 ,并对 2 N 2 0的 N阶 B样条函数 ,得出了使其分析小波函数具有最优时 -频分辨特性的条件 .该条件表明 :B样条函数的阶数较低时 ,其分析小波函数的时 -频分辨特性较好 ,并且 N取偶数时的 B样条双正交小波的时 -频分辨特性要相对优于 N取奇数时的 B样条双正交小波的时 -频分辨特性 .据此条件 ,可以求出相应的对偶尺度函数和小波函数 .最后 ,通过选用几个典型的双正交小波进行编码模拟实验 。 展开更多
关键词 双正交小波 b样条函数 -频窗 尺度函数 -频分辨特性 图像编码 视频编码
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