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Curve interpolation model for visualising disjointed neural elements
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作者 Mohd Shafry Mohd Rahim Norhasana Razzali +2 位作者 Mohd Shahrizal Sunar Ayman Abdualaziz Abdullah Amjad Rehman 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第21期1637-1644,共8页
Neuron cell are built from a myriad of axon and denddte structures. It transmits electrochemical signals between the brain and the nervous system. Three-dimensional visualization of neuron structure could help to faci... Neuron cell are built from a myriad of axon and denddte structures. It transmits electrochemical signals between the brain and the nervous system. Three-dimensional visualization of neuron structure could help to facilitate deeper understanding of neuron and its models. An accurate neuron model could aid understanding of brain's functionalities, diagnosis and knowledge of entire nervous system. Existing neuron models have been found to be defective in the aspect of realism. Whereas in the actual biological neuron, there is continuous growth as the soma extending to the axon and the dendrite; but, the current neuron visualization models present it as disjointed segments that has greatly mediated effective realism. In this research, a new reconstruction model comprising of the Bounding Cylinder, Curve Interpolation and Gouraud Shading is proposed to visualize neuron model in order to improve realism. The reconstructed model is used to design algorithms for generating neuron branching from neuron SWC data. The Bounding Cylinder and Curve Interpolation methods are used to improve the connected segments of the neuron model using a series of cascaded cylinders along the neuron's connection path. Three control points are proposed between two adjacent neuron segments. Finally, the model is rendered with Gouraud Shading for smoothening of the model surface. This produce a near-perfection model of the natural neurons with attended realism. The model is validated by a group of bioinformatics analysts' responses to a predefined survey. The result shows about 82% acceptance and satisfaction rate. 展开更多
关键词 bounding cylinder curve interpolation reconstruction model Gouraud shading neuralregeneration
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Calculation of Space NURBS Curve Interpolation Error 被引量:1
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作者 Liangji Chen Fei Gao +1 位作者 Bo Zhao Longfei Ma 《Journal of Computer and Communications》 2020年第6期1-9,共9页
Aiming at the problem of low accuracy of interpolation error calculation of existing NURBS curves, an approximate method for the distance between a point and a NURBS interpolation curve is proposed while satisfying th... Aiming at the problem of low accuracy of interpolation error calculation of existing NURBS curves, an approximate method for the distance between a point and a NURBS interpolation curve is proposed while satisfying the accuracy of the solution. Firstly, the minimum parameter interval of the node vector corresponding to the data point under test in the original data point sequence is determined, and the parameter interval is subdivided according to the corresponding step size, and the corresponding parameter value is obtained. Secondly, the distance from the measured point to the NURBS curve is calculated, and the nearest distance is found out. The node interval is subdivided again on one side of the nearest distance. Finally, the distance between the data point to be measured and each subdivision point is calculated again, and the minimum distance is taken as the interpolation error between the point and the NURBS curve. The simulation results of actual tool position data show that this method can more accurately obtain the error of spatial NURBS interpolation curve. 展开更多
关键词 Computer-Aided Design NURBS interpolation curve interpolation Error Approximation Solution
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CURVE AND SURFACE INTERPOLATIONBY SUBDIVISION ALGORITHMS 被引量:1
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作者 Ruibin Qu 《Computer Aided Drafting,Design and Manufacturing》 1994年第2期28-39,共2页
Interpolatory subdivision algorithms for the generation of curves and surfaces play a veryimportant rule in shape design and modelling in CAD/CAM systems. In this paper, by using the dif-ference and divided difference... Interpolatory subdivision algorithms for the generation of curves and surfaces play a veryimportant rule in shape design and modelling in CAD/CAM systems. In this paper, by using the dif-ference and divided difference analysis, a systematic method to construct Cn (n≥ 0) interpolatorycurves by subdivision from given data is described and the mask (filter) of the algorithm is presentedexplicitly. This algorithm generates a Cn smooth curve which interpolates the initial control points.Control parameters are also provided so that the shape of the final curve can be adjusted according torequirements. An immediate generalisation of the method is the construction of smooth interpolatorysubdivision algorithms over uniform triangular networks (tensor product type data) in Rm. The mainresults of this algorithm for smooth interpolatory surface subdivision algorrthm are also included.AMS(MOS) : 65D05 , 65D15 , 65D17. 展开更多
关键词 curve and surface interpolation subdivision algorithm divided difference generationpolynomial uniform triangulation WAVELET
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NURBS CURVE INTERPOLATOR WITH ADAPTIVE ACCELERATION-DECELERATION CONTROL 被引量:2
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作者 刘凯 赵东标 陆永华 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第4期241-247,共7页
The feedrate profile of non-uniform rational B-spline (NURBS) interpolation due to the contour errors is analyzed. A NURBS curve interpolator with adaptive acceleration-deceleration control is presented. In interpo-... The feedrate profile of non-uniform rational B-spline (NURBS) interpolation due to the contour errors is analyzed. A NURBS curve interpolator with adaptive acceleration-deceleration control is presented. In interpo- lation preprocessing, the sensitive zones of feedrate variations are processed with acceleration-deceleration control. By using the proposed algorithm, the machining accuracy is guaranteed and the feedrate is adaptively adjusted to he smoothed. The mechanical shock imposed in the servo system is avoided by the first and the second time derivatives of feedrates. A simulation of NURBS interpolation is given to demonstrate the validity and the effectiveness of the algorithm. The proposed interpolator can also be applied to the trajectory planning of the other parametric curves. 展开更多
关键词 numerical control systems interpolation adaptive algorithms NURBS curve interpolator adaptive acceleration and deceleration limited jerk
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LOOK-AHEAD ALGORITHM FOR VELOCITY CONTROL BASED ON PARAMETERIZED CURVE INTERPOLATOR 被引量:2
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作者 REN Kun FU Jianzhong CHEN Zichen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第2期23-26,共4页
To avoid suffering gouge and transient overshooting in high speed cutting machining, a novel parametefized curve interpolator model with velocity look-ahead algorithm is proposed. Based on a prearrangement step interp... To avoid suffering gouge and transient overshooting in high speed cutting machining, a novel parametefized curve interpolator model with velocity look-ahead algorithm is proposed. Based on a prearrangement step interpolation algorithm for parameterized curves and considering high curvature points, parameterized curve tool path is divided into acceleration segments and deceleration segments by look-ahead algorithm. Under condition of characteristics of acceleration and deceleration stored in control system, deceleration before high curvature points and acceleration after high curvature points are realized in real-time in high speed cutting machining. Based on new parameterized curve interpolator model with velocity look-ahead algorithm, a real cubic spline is machined simulativly. The simulation results show that velocity look-ahead algorithm improves velocity changing more smoothly. 展开更多
关键词 High speed cutting machining Parameterized curve interpolator Look-ahead algorithm
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C2 Continuous Quartic Hermite Spline Curves with Shape Parameters
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作者 li jun-cheng liu chrng-zhi ma fu-ming 《Communications in Mathematical Research》 CSCD 2017年第3期193-204,共12页
In order to relieve the deficiency of the usual cubic Hermite spline curves,the quartic Hermite spline curves with shape parameters is further studied in this work. The interpolation error and estimator of the quartic... In order to relieve the deficiency of the usual cubic Hermite spline curves,the quartic Hermite spline curves with shape parameters is further studied in this work. The interpolation error and estimator of the quartic Hermite spline curves are given. And the characteristics of the quartic Hermite spline curves are discussed.The quartic Hermite spline curves not only have the same interpolation and continuity properties of the usual cubic Hermite spline curves, but also can achieve local or global shape adjustment and C;continuity by the shape parameters when the interpolation conditions are fixed. 展开更多
关键词 Hermite spline curve interpolation curve shape adjustment C^2 continuous
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Many-Knot Spline Interpolating Curves and Their Applications in Font Design 被引量:2
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作者 Yan Weiqi Qi Dongxu(CAD Laboratory, Institute of Computing Technology. Academic Sinica. Beijing.P.R.China 100080 CAD Research Center. North China University of Technology, Beijing.P.R.China,100041) 《Computer Aided Drafting,Design and Manufacturing》 1999年第1期1-8,共8页
Many-knot spline interpolating is a class of curves and surfaces fitting method presentedin 1974. Many-knot spline interpolating curves are suitable to computer aided geometric design anddata points interpolation. In ... Many-knot spline interpolating is a class of curves and surfaces fitting method presentedin 1974. Many-knot spline interpolating curves are suitable to computer aided geometric design anddata points interpolation. In this paped, the properties of many-knot spline interpolating curves arediscussed and their applications in font design are considered. The differences between many-knotspline interpolating curves and the curves genoaed by exceeding-lacking adjuStment algorithm aregiven. 展开更多
关键词 many-knot spline interpolating curves font design SUBDIVISION CONTINUITY
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Neural Network Methods for NURBS Curve and Surface Interpolation
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作者 秦开怀 《Journal of Computer Science & Technology》 SCIE EI CSCD 1997年第1期76-89,共14页
New algorithms based on artificial neural network models are presented for cubic NURBS cuxve and surface interpolation. When all the knot spans are identical, the NURBS curve interpolation procedtire degenerates into ... New algorithms based on artificial neural network models are presented for cubic NURBS cuxve and surface interpolation. When all the knot spans are identical, the NURBS curve interpolation procedtire degenerates into that of uniform rational B-spline curves. If all the weights of data points are identical,then the NURBS curve interpolation procedure degenerates into the integral B-spline curve interpolation. 展开更多
关键词 Neural network NURBS curve interpolation surface interpolation
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C^2-(C^3-) Continuous Interpolation Spline Curve and Surface
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作者 方逵 谭建荣 朱国庆 《Journal of Computer Science & Technology》 SCIE EI CSCD 1998年第3期238-245,共8页
Free-formed or sculptured surfaces in engineering products are frequently constructed from a set of measured 3D data points. C2- (C3-) continuity approach is important in this field. This paper presents a method of re... Free-formed or sculptured surfaces in engineering products are frequently constructed from a set of measured 3D data points. C2- (C3-) continuity approach is important in this field. This paper presents a method of rectangular interpolation of given 3D data array which is regularly arranged. The interpolation surface which is constructed by tensor product has desirable properties (second-order or third-order continuity locality) and is implemented and adjusted easily. Higher order continuity methods are also briefly discussed. 展开更多
关键词 CAGD interpolation spline curve interpolation spline surface
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Integration of a 5-axis Spline Interpolation Controller in an Open CNC System 被引量:4
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作者 王永章 刘源 +1 位作者 韩振宇 邵忠喜 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2009年第2期218-224,共7页
A 5-axis controller with curve interpolation function is developed to satisfy high-speed and high-precision computer numerical control (CNC) machining of machine parts with complex shapes in the authors-devised open C... A 5-axis controller with curve interpolation function is developed to satisfy high-speed and high-precision computer numerical control (CNC) machining of machine parts with complex shapes in the authors-devised open CNC system. The instruction for- mat of this interpolation method and the generation procedure of the numerical control (NC) files are introduced. The interpola- tion curves of both position vectors and orientation vectors constructed by the controller are C2 continuous and independent of machin... 展开更多
关键词 numerical control systems sculptured surfaces 5-axis machining motion control curve interpolation
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A Class of Spline Curves with Four Local Shape Parameters 被引量:2
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作者 Yuan-peng ZHU Xu-li HAN 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2017年第4期979-988,共10页
A class of spline curves with four local shape parameters, which includes the quartic spline curves with three local shape parameters given in Han [Xuli Han. A class of general quartic spline curves with shape paramet... A class of spline curves with four local shape parameters, which includes the quartic spline curves with three local shape parameters given in Han [Xuli Han. A class of general quartic spline curves with shape parameters. Comput. Aided Geom. Design, 28:151-163 (2011)], is proposed. Without solving a linear system, the spline curves can be used to interpolate sets of points with C2 continuity partly or entirely. The shape parameters have a predictable adjusting role on the sp[ine curves. 展开更多
关键词 B-spline curve quartic spline curve interpolation curve shape control shape parameter
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ALGEBRAIC-GEOMETRY FOUNDATION FOR CONSTRUCTING SMOOTH INTERPOLANTS ON CURVED SIDES ELEMENT 被引量:2
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作者 Z.X. Luo(Institute of Mathematical Sciences, Dalian University of Technology, Dalian, China) 《Journal of Computational Mathematics》 SCIE CSCD 1995年第4期343-350,共8页
The aim of this paper is to lay a algebraic geometry foundation for constructing smoothing interpolants on curved side element. Some interpolation theorems in polynomial space are given. The main results effectively f... The aim of this paper is to lay a algebraic geometry foundation for constructing smoothing interpolants on curved side element. Some interpolation theorems in polynomial space are given. The main results effectively for CAGD are presented. 展开更多
关键词 CAGD Wang Rational ALGEBRAIC-GEOMETRY FOUNDATION FOR CONSTRUCTING SMOOTH INTERPOLANTS ON curveD SIDES ELEMENT
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Determining Knots by Minimizing Energy 被引量:5
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作者 张彩明 韩慧健 郑复华 《Journal of Computer Science & Technology》 SCIE EI CSCD 2006年第2期261-264,共4页
A new method for determining knots to construct polynomial curves is presented. At each data point, a quadric curve which passes three consecutive points is constructed. The knots for constructing the quadric curve ar... A new method for determining knots to construct polynomial curves is presented. At each data point, a quadric curve which passes three consecutive points is constructed. The knots for constructing the quadric curve are determined by minimizing the internal strain energy, which can be regarded as a function of the angle. The function of the angle is expanded as a Taylor series with two terms, then the two knot intervals between the three consecutive points are defined by linear expression. Between the two consecutive points, there are two knot intervals, and the combination of the two knot intervals is used to define the final knot interval. A comparison of the new method with several existing methods is included. 展开更多
关键词 KNOTS interpolation curve strain energy shape preserving
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