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B-Spline Wavelet on Interval Finite Element Method for Static and Vibration Analysis of Stiffened Flexible Thin Plate 被引量:6
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作者 Xing Wei Wen Chen +3 位作者 Bin Chen Bin Chen2 Bin Chen3 Bin Chen4 《Computers, Materials & Continua》 SCIE EI 2016年第4期53-71,共19页
A new wavelet finite element method(WFEM)is constructed in this paper and two elements for bending and free vibration problems of a stiffened plate are analyzed.By means of generalized potential energy function and vi... A new wavelet finite element method(WFEM)is constructed in this paper and two elements for bending and free vibration problems of a stiffened plate are analyzed.By means of generalized potential energy function and virtual work principle,the formulations of the bending and free vibration problems of the stiffened plate are derived separately.Then,the scaling functions of the B-spline wavelet on the interval(BSWI)are introduced to discrete the solving field variables instead of conventional polynomial interpolation.Finally,the corresponding two problems can be resolved following the traditional finite element frame.There are some advantages of the constructed elements in structural analysis.Due to the excellent features of the wavelet,such as multi-scale and localization characteristics,and the excellent numerical approximation property of the BSWI,the precise and efficient analysis can be achieved.Besides,transformation matrix is used to translate the meaningless wavelet coefficients into physical space,thus the resolving process is simplified.In order to verify the superiority of the constructed method in stiffened plate analysis,several numerical examples are given in the end. 展开更多
关键词 b-spline wavelet on the interval wavelet finite element method Stiffened plate Bending analysis Vibration analysis
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Geometry Modeling of Ship Hull Based on Non-uniform B-spline 被引量:4
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作者 王虎 邹早建 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第2期189-192,共4页
In order to generate the three-dimensional (3-D) hull surface accurately and smoothly,a mixed method which is made up of non-uniform B-spline together with an iterative procedure was developed.By using the iterative m... In order to generate the three-dimensional (3-D) hull surface accurately and smoothly,a mixed method which is made up of non-uniform B-spline together with an iterative procedure was developed.By using the iterative method the data points on each section curve are calculated and the generalized waterlines and transverse section curves are determined.Then using the non-uniform B-spline expression,the control vertex net of the hull is calculated based on the generalized waterlines and section curves.A ship with tunnel stern was taken as test case.The numerical results prove that the proposed approach for geometry modeling of 3-D ship hull surface is accurate and effective. 展开更多
关键词 hull surface geometry modeling non-uniform b-spline iterative procedure
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THE CONSTRUCTION OF WAVELET-BASED TRUNCATED CONICAL SHELL ELEMENT USING B-SPLINE WAVELET ON THE INTERVAL 被引量:7
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作者 Xiang Jiawei He Zhengjia Chen Xuefeng 《Acta Mechanica Solida Sinica》 SCIE EI 2006年第4期316-326,共11页
Based on B-spline wavelet on the interval (BSWI), two classes of truncated conical shell elements were constructed to solve axisymmetric problems, i.e. BSWI thin truncated conical shell element and BSWI moderately t... Based on B-spline wavelet on the interval (BSWI), two classes of truncated conical shell elements were constructed to solve axisymmetric problems, i.e. BSWI thin truncated conical shell element and BSWI moderately thick truncated conical shell element with independent slopedeformation interpolation. In the construction of wavelet-based element, instead of traditional polynomial interpolation, the scaling functions of BSWI were employed to form the shape functions through the constructed elemental transformation matrix, and then construct BSWI element via the variational principle. Unlike the process of direct wavelets adding in the wavelet Galerkin method, the elemental displacement field represented by the coefficients of wavelets expansion was transformed into edges and internal modes via the constructed transformation matrix. BSWI element combines the accuracy of B-spline function approximation and various wavelet-based elements for structural analysis. Some static and dynamic numerical examples of conical shells were studied to demonstrate the present element with higher efficiency and precision than the traditional element. 展开更多
关键词 b-spline wavelet on the interval finite element method axisymmetric problem truncated conical shell element
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Edge detection of molten pool and weld line for CO_2 welding based on B-spline wavelet 被引量:2
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作者 薛家祥 贾林 +1 位作者 李海宝 张丽玲 《China Welding》 EI CAS 2004年第2期137-141,共5页
Due to the disturbances of spatters, dusts and strong arc light, it is difficult to detect the molten pool edge and the weld line location in CO_2 welding processes. The median filtering and self-multiplication was em... Due to the disturbances of spatters, dusts and strong arc light, it is difficult to detect the molten pool edge and the weld line location in CO_2 welding processes. The median filtering and self-multiplication was employed to preprocess the image of the CO_2 welding in order to detect effectively the edge of molten pool and the location of weld line. The B-spline wavelet algorithm has been investigated, the influence of different scales and thresholds on the results of the edge detection have been compared and analyzed. The experimental results show that better performance to extract the edge of the molten pool and the location of weld line can be obtained by using the B-spline wavelet transform. The proposed edge detection approach can be further applied to the control of molten depth and the seam tracking. 展开更多
关键词 CO_2 welding molten pool b-spline wavelet edge detection
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Two Dimensional Tensor Product B-Spline Wavelet Scaling Functions for the Solution of Two-Dimensional Unsteady Diffusion Equations
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作者 XIONG Lei LI haijiao ZHANG Lewen 《Journal of Ocean University of China》 SCIE CAS 2008年第3期258-262,共5页
The fourth-order B spline wavelet scaling functions are used to solve the two-dimensional unsteady diffusion equation. The calculations from a case history indicate that the method provides high accuracy and the compu... The fourth-order B spline wavelet scaling functions are used to solve the two-dimensional unsteady diffusion equation. The calculations from a case history indicate that the method provides high accuracy and the computational efficiency is enhanced due to the small matrix derived from this method.The respective features of 3-spline wavelet scaling functions,4-spline wavelet scaling functions and quasi-wavelet used to solve the two-dimensional unsteady diffusion equation are compared. The proposed method has potential applications in many fields including marine science. 展开更多
关键词 wavelet analysis b-spline wavelet tensor product RESOLUTION diffusion equations
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A Study on B-Spline Wavelets and Wavelet Packets
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作者 Sana Khan Mohammad Kalimuddin Ahmad 《Applied Mathematics》 2014年第19期3001-3010,共10页
In this paper, we discuss the B-spline wavelets introduced by Chui and Wang in [1]. The definition for B-spline wavelet packets is proposed along with the corresponding dual wavelet packets. The properties of B-spline... In this paper, we discuss the B-spline wavelets introduced by Chui and Wang in [1]. The definition for B-spline wavelet packets is proposed along with the corresponding dual wavelet packets. The properties of B-spline wavelet packets are also investigated. 展开更多
关键词 b-splineS SPLINE waveletS wavelet PACKETS
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An Approach to Representing Heterogeneous Non-Uniform Rational B-Spline Objects
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作者 臧婷 徐安平 《Transactions of Tianjin University》 EI CAS 2011年第4期275-279,共5页
The representation method of heterogeneous material information is one of the key technologies of heterogeneous object modeling, but almost all the existing methods cannot represent non-uniform rational B-spline (NU... The representation method of heterogeneous material information is one of the key technologies of heterogeneous object modeling, but almost all the existing methods cannot represent non-uniform rational B-spline (NURBS) entity. According to the characteristics of NURBS, a novel data structure, named NURBS material data structure, is proposed, in which the geometrical coordinates, weights and material coordinates of NURBS heterogene- ous objects can be represented simultaneously. Based on this data structure, both direct representation method and inverse construction method of heterogeneous NURBS objects are introduced. In the direct representation method, three forms of NURBS heterogeneous objects are introduced by giving the geometry and material information of con- trol points, among which the homogeneous coordinates form is employed for its brevity and easy programming. In the inverse construction method, continuous heterogeneous curves and surfaces can he obtained by interpolating discrete points and curves with specified material information. Some examples are given to show the effectiveness of the pro- posed methods. 展开更多
关键词 heterogeneous object non-uniform rational b-spline (NURBS) material data structure direct represen- tation method inverse construction method
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Extraction of Feature Points for Non-Uniform Rational B-Splines(NURBS)-Based Modeling of Human Legs
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作者 WANG Xi WU Zongqian LI Qiao 《Journal of Donghua University(English Edition)》 CAS 2022年第4期299-303,共5页
Methods of digital human modeling have been developed and utilized to reflect human shape features.However,most of published works focused on dynamic visualization or fashion design,instead of high-accuracy modeling,w... Methods of digital human modeling have been developed and utilized to reflect human shape features.However,most of published works focused on dynamic visualization or fashion design,instead of high-accuracy modeling,which was strongly demanded by medical or rehabilitation scenarios.Prior to a high-accuracy modeling of human legs based on non-uniform rational B-splines(NURBS),the method of extracting the required quasi-grid network of feature points for human legs is presented in this work.Given the 3 D scanned human body,the leg is firstly segmented and put in standardized position.Then re-sampling of the leg is conducted via a set of equidistant cross sections.Through analysis of leg circumferences and circumferential curvature,the characteristic sections of the leg as well as the characteristic points on the sections are then identified according to the human anatomy and shape features.The obtained collection can be arranged to form a grid of data points for knots calculation and high-accuracy shape reconstruction in future work. 展开更多
关键词 3D scan digital human modeling non-uniform rational b-splines(NURBS) feature extraction
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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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A New Isogeometric Finite Element Method for Analyzing Structures
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作者 Pan Su Jiaxing Chen +1 位作者 Ronggang Yang Jiawei Xiang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第11期1883-1905,共23页
High-performance finite element research has always been a major focus of finite element method studies.This article introduces isogeometric analysis into the finite element method and proposes a new isogeometric fini... High-performance finite element research has always been a major focus of finite element method studies.This article introduces isogeometric analysis into the finite element method and proposes a new isogeometric finite element method.Firstly,the physical field is approximated by uniform B-spline interpolation,while geometry is represented by non-uniform rational B-spline interpolation.By introducing a transformation matrix,elements of types C^(0)and C^(1)are constructed in the isogeometric finite element method.Subsequently,the corresponding calculation formats for one-dimensional bars,beams,and two-dimensional linear elasticity in the isogeometric finite element method are derived through variational principles and parameter mapping.The proposed method combines element construction techniques of the finite element method with geometric construction techniques of isogeometric analysis,eliminating the need for mesh generation and maintaining flexibility in element construction.Two elements with interpolation characteristics are constructed in the method so that boundary conditions and connections between elements can be processed like the finite element method.Finally,the test results of several examples show that:(1)Under the same degree and element node numbers,the constructed elements are almost consistent with the results obtained by traditional finite element method;(2)For bar problems with large local field variations and beam problems with variable cross-sections,high-degree and multi-nodes elements constructed can achieve high computational accuracy with fewer degrees of freedom than finite element method;(3)The computational efficiency of isogeometric finite element method is higher than finite element method under similar degrees of freedom,while as degrees of freedom increase,the computational efficiency between the two is similar. 展开更多
关键词 Finite element method isogeometric analysis uniform b-spline non-uniform rational b-spline beam and bar
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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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A Modified Non-Uniform DMT Transceiver for the Digital Subscriber Line
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作者 Sobia Baig M.Junaid Mughal 《China Communications》 SCIE CSCD 2007年第4期40-44,共5页
A Non-Uniform Discrete-Multitone(DMT) transceiver can help mitigate the channel-noise enhancement,attributed to zero-forcing equalization (ZFE) technique,by splitting the channel frequency response into octave spaced ... A Non-Uniform Discrete-Multitone(DMT) transceiver can help mitigate the channel-noise enhancement,attributed to zero-forcing equalization (ZFE) technique,by splitting the channel frequency response into octave spaced subbands.This paper presents a novel quantitative analys is of the channel-noise enhancement in different subbands of the Non-Uniform DMT system.In order to improve the bit error rate(BER) performance,a modified Non-Uniform DMT transceiver is proposed.The BER performance of the modified Non-Uniform DMT system is compared with that of the Non-Uniform DMT and conventional DMT systems in a Digital Subscriber Line(DSL). 展开更多
关键词 non-uniform DMT wavelet filter BANKS ZERO-FORCING EQUALIZATION
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The Irregular Weighted Wavelet Frame Conjugate Gradient Algorithm
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作者 Jiang Li Yi Aichun +1 位作者 Zhang Changfan Zhu Shanhua 《China Communications》 SCIE CSCD 2007年第4期48-54,共7页
The dropping off of data during information transmission and the storage device’s damage etc.often leads the sampled data to be non-uniform.The paper, based on the stability theory of irregular wavelet frame and the ... The dropping off of data during information transmission and the storage device’s damage etc.often leads the sampled data to be non-uniform.The paper, based on the stability theory of irregular wavelet frame and the irregular weighted wavelet frame operator,proposed an irregular weighted wavelet fame conjugate gradient iterative algorithm for the reconstruction of non-uniformly sampling signal. Compared the experiment results with the iterative algorithm of the Ref.[5],the new algorithm has remarkable advantages in approximation error,running time and so on. 展开更多
关键词 non-uniform sampling FRAME ALGORITHM IRREGULAR wavelet FRAME CONJUGATE gradient ALGORITHM
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4TH-ORDER SPLINE WAVELETS ON A BOUNDED INTERVAL
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作者 段继伟 李启光 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第4期437-446,共10页
The 4th-order spline wavelets an a bounded interval are constructed by the 4th-order truncated B-spline functions. These wavelets consist of inner and boundary wavelets. They are bases of wavelet space with finite dim... The 4th-order spline wavelets an a bounded interval are constructed by the 4th-order truncated B-spline functions. These wavelets consist of inner and boundary wavelets. They are bases of wavelet space with finite dimensions. Arty function on an interval will be expanded as the sum of finite items of the scaling functions and wavelets. It plays an important role for numerical analysis of partial differential equations, signal processes, and other similar problems. 展开更多
关键词 b-spline wavelet bounded interval
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Study on spline wavelet finite-element method in multi-scale analysis for foundation
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作者 Qiang Xu Jian-Yun Chen +2 位作者 Jing Li Gang Xu Hong-Yuan Yue 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第5期699-708,共10页
A new finite element method (FEM) of B-spline wavelet on the interval (BSWI) is proposed. Through analyzing the scaling functions of BSWI in one dimension, the basic formula for 2D FEM of BSWI is deduced. The 2D F... A new finite element method (FEM) of B-spline wavelet on the interval (BSWI) is proposed. Through analyzing the scaling functions of BSWI in one dimension, the basic formula for 2D FEM of BSWI is deduced. The 2D FEM of 7 nodes and 10 nodes are constructed based on the basic formula. Using these proposed elements, the multiscale numerical model for foundation subjected to harmonic periodic load, the foundation model excited by external and internal dynamic load are studied. The results show the pro- posed finite elements have higher precision than the tradi- tional elements with 4 nodes. The proposed finite elements can describe the propagation of stress waves well whenever the foundation model excited by extemal or intemal dynamic load. The proposed finite elements can be also used to con- nect the multi-scale elements. And the proposed finite elements also have high precision to make multi-scale analysis for structure. 展开更多
关键词 Finite-element method Dynamic response b-spline wavelet on the interval Multi-scale analysis
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Wavelet Collocation Method for Solving Elliptic Singularly Perturbed Problem
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作者 Bin Lin 《Journal of Applied Mathematics and Physics》 2019年第1期166-171,共6页
Wavelet collocation method is used to solve an elliptic singularly perturbed problem with two parameters. The B-spline function is used as a single mother wavelet, which leads to a tri-diagonal linear system. The accu... Wavelet collocation method is used to solve an elliptic singularly perturbed problem with two parameters. The B-spline function is used as a single mother wavelet, which leads to a tri-diagonal linear system. The accuracy of the proposed method is demonstrated by test problem and the result shows the reliability and efficiency of the method. 展开更多
关键词 b-spline FUNCTIONS wavelet COLLOCATION Method ELLIPTIC Singularly PERTURBED Problems
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Multiresolution for Closed Curves and Surfaces Using Wavelets
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作者 ZHAO Gang BAI Jie WANG Chao YAO Fu-sheng 《Computer Aided Drafting,Design and Manufacturing》 2005年第2期1-13,共13页
Multiresolution modeling is becoming a powerful tool for fast display, and geometric data compression and transmission of complex shapes. Most of the existing literatures investigating the multiresolution for B-spline... Multiresolution modeling is becoming a powerful tool for fast display, and geometric data compression and transmission of complex shapes. Most of the existing literatures investigating the multiresolution for B-spline curves and surfaces are concentrated on open ones. In this paper, we focus on the multiresolution representations and editing of closed B-spline curves and surfaces using wavelets. A repetition approach is adopted for the multiresolution analysis of closed B-spline curves and surfaces. Since the closed curve or surface itself is periodic, it can overcome the drawback brought by the repetition method, i.e. introducing the discontinuities at the boundaries. Based on the models at different multiresolution levels, the multiresolution editing methods of closed curves and surfaces are introduced. Users can edit the overall shape of a closed one while preserving its details, or change its details without affecting its overall shape. 展开更多
关键词 closed b-spline curves closed b-spline surfaces waveletS multiresolution representation analysis multiresolution representation multiresolution editing
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基于小波的非均匀B样条曲线自动光顺算法 被引量:12
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作者 赵罡 王爱增 穆国旺 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2010年第11期1925-1931,共7页
为了更好地对曲线进行自动光顺,针对一般的非均匀B样条曲线,提出一种基于非均匀B样条小波的曲线光顺算法.首先将曲线分解为尺度部分和细节部分,并把细节部分再次分解为小波尺度部分和小波细节部分;然后通过自动设定阈值对小波细节部分... 为了更好地对曲线进行自动光顺,针对一般的非均匀B样条曲线,提出一种基于非均匀B样条小波的曲线光顺算法.首先将曲线分解为尺度部分和细节部分,并把细节部分再次分解为小波尺度部分和小波细节部分;然后通过自动设定阈值对小波细节部分进行修复,并通过小波重构得到新的控制顶点;最后对新的控制顶点进行迭代计算,直至达到满意的光顺效果.通过设定光顺误差限,采用该算法可以在计算机上对曲线进行自动光顺操作.实例验证表明,文中算法比其他基于小波的曲线光顺方法具有更好的光顺效果. 展开更多
关键词 B-样条 光顺 非均匀B-样条小波 曲线 小波分析
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NURBS曲线曲面的多分辨率几何建模 被引量:7
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作者 李爱民 方宗德 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2010年第8期1339-1343,共5页
针对均匀和准均匀B样条小波多分辨率建模表示能力和适应性的不足,基于离散内积和非均匀B样条节点插入算法建立了一种非均匀半正交B样条小波,并进一步论述了其在非均匀B样条曲线曲面中的多分辨率设计.最后通过实例对非均匀B样条曲线曲面... 针对均匀和准均匀B样条小波多分辨率建模表示能力和适应性的不足,基于离散内积和非均匀B样条节点插入算法建立了一种非均匀半正交B样条小波,并进一步论述了其在非均匀B样条曲线曲面中的多分辨率设计.最后通过实例对非均匀B样条曲线曲面中的多分辨率建模进行了说明和验证. 展开更多
关键词 NURBS 几何建模 非均匀B样条小波 多分辨率分析
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基于非均匀B样条小波的服装纸样优化识别方法及应用 被引量:2
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作者 朱同林 刘越畅 +1 位作者 柴丽芳 章晓华 《华南农业大学学报》 CAS CSCD 北大核心 2004年第4期107-110,共4页
针对服装样片纸样的形状与结构特点,提出一种由曲率确定型值点分布的非均匀B样条曲线拟合识别方法,并用其样条小波进行型值点压缩和优化,以达到在给定误差下型值点数目尽量少的目的.通过分析比较和实例检验表明,这种算法识别服装纸样方... 针对服装样片纸样的形状与结构特点,提出一种由曲率确定型值点分布的非均匀B样条曲线拟合识别方法,并用其样条小波进行型值点压缩和优化,以达到在给定误差下型值点数目尽量少的目的.通过分析比较和实例检验表明,这种算法识别服装纸样方便可靠,为服装计算机辅助设计(CAD)中样片的编辑设计提供一种智能高效的输入技术. 展开更多
关键词 非均匀B样条小波 服装纸样 优化识别方法 型值点优化
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