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1.
为了改进参数曲面自由变形方法,构造了四边形区域上的伸缩因子函数,它不仅具有已往文献所引入的伸缩因子的特性,还可以在区域上达到峰值,从而克服现有的伸缩因子仅在一点达到峰值的不足,变形区域也由圆形域变为四边形区域.使用四边形区域上的伸缩因子函数去作用待变形曲面的参数方程,从而使曲面在四边形区域上发生形变,并且可通过交互改变控制参数来控制所曲面变形的形状,使其能够更好的表示一些实体的外型.最后,实验结果表明,该方法的数学比较背景简单、各个参数容易控制、重复使用该因子作用于变形曲面,可获得丰富的变形效果.该伸缩因子可应用于几何造型、计算机图形学、计算机动画以及CAD/CAM等众多领域.  相似文献   

2.
提出了一种基于伸缩因子的代数曲线曲面变形方法。首先构造了一种用于代数曲线曲面变形的伸缩因子,然后将所构造的伸缩因子分别作用于待变形的代数曲线与曲面,通过改变伸缩因子各参数的取值实现对代数曲线曲面的变形。实例表明,该方法操作方便,易于控制,可获得丰富的变形效果,是一种简单有效的代数曲线曲面变形方法。  相似文献   

3.
具有区间峰值的曲面伸缩因子及其实验   总被引:1,自引:1,他引:0       下载免费PDF全文
为了改进参数曲面自由变形方法,构造了一种新的伸缩因子函数,它不仅具有以往文献所引入的伸缩因子的特性,还可以在区域上达到峰值,从而克服现有的伸缩因子仅在一点达到峰值的不足。使用新的伸缩因子去作用待变形的曲面方程,从而使曲面发生形变,通过交互改变控制参数来控制曲面的形状,使其能够更好地表示一些实体的外型。实验表明,该方法数学背景简单,易于控制,重复使用可获得丰富的变形效果。适用于几何造型、计算机动画、CAD/CAM等领域。  相似文献   

4.
参数曲线曲面自由变形的多项式因子方法   总被引:1,自引:0,他引:1  
为得到理想的造型效果,提出一种空间参数曲线曲面自由变形的方法.首先引入基于多项式的伸缩因子,并构造了空间变形矩阵;然后将变形矩阵或伸缩因子作用于待变形曲线曲面方程,从而得到形变效果.实验结果表明,该方法计算简单、易于控制,可得到较好的变形效果.  相似文献   

5.
为了对参数曲面进行精确变形,可通过构造特殊矢量伸缩函数来实现参数曲面的捕值变形.变形时,先在曲面选取变形辅助点,并利用这些辅助点构造矢量伸缩甬数;然后基于矢量叠加原理用此伸缩矢量函数去作用曲面,使曲面发生变形且变形后通过给定的插值点.插值变形结果表明,此方法不仅能够精确控制变形范围,而且在变形与未变形部分之间具有C2连续性.  相似文献   

6.
为了获得丰富的曲面造型效果,构造了一种兼具单峰性和区域峰值性,支撑区域为任意凸多边形域的伸缩因子.首先引入基于凸多边形域的伸缩因子;然后构造了空间变形矩阵;最后将上述变形矩阵作用于待变形曲面的方程上,获得相应的变形效果.数值实例结果表明,通过调控支撑区域、峰值区域、变形中心、主方向、伸缩参数和光滑参数,可以灵活地对曲面变形;该方法不仅计算简单、易于控制,还能精确地控制变形的范围,迭加使用可以得到丰富的变形效果.  相似文献   

7.
基于伸缩因子的参数曲线自由变形   总被引:8,自引:0,他引:8  
提出一种新的参数曲线自由变形方法:构造出特殊的伸缩因子函数,以此去作用(伸缩)待变形曲线方程,从而使曲线发生形变,通过交互改变控制参数,可达到预期的变形效果,实验表明,该方法数学背景简单,易于控制,重复使用可获得丰富的变形效果,适用于几何造型,计算机动画等领域。  相似文献   

8.
目的 随着科学技术的快速发展,曲线的几何造型技术开始成为近来的热点研究方向.为了获得更多的变形效果,面向2维、3维参数曲线和自由曲线变形,提出一种带平台伸缩函数的变形方法。方法 有别于现有的大多数自由变形算法,首先构造了一种形式简洁的多项式形式伸缩函数;其次借助于伸缩函数,构造了含有伸缩参数与光滑参数的新型伸缩因子,算法表明,这种新型伸缩因子具有单点峰值性、区间峰值性、对称性等优良性质;最后将伸缩因子所构造变形矩阵作用于待变形的曲线,通过控制变形区间、伸缩参数、光滑参数以及变形方向,可以获得整体的、局部的、周期的、伸缩的等各类丰富的图形效果。结果 此变形操作对造型系统中的主流参数曲线(Bézier和NURBS)具有封闭性;通过大量数值实例表明了该方法计算量小,可控性强,重复使用可以得到形状多样、具有艺术效果的轮廓线等效果。结论 与其他方法相比,本文算法不仅可以用于一般的平面与空间参数曲线,也可以用于自由型曲线,扩大了多数自由变形算法的适用范围;由于伸缩函数具备单点峰值性、区间峰值性、对称性等性质,从而能够产生以前变形方法无法产生各类角点、尖点的特殊曲线,在一定程度上极大丰富了曲线的变形效果。  相似文献   

9.
提出一种全新的参数曲线自由变形方法:基于平面矢量叠加原理构造出特殊的伸缩矢量函数去作用待变形曲线,从而使曲线发生形变,通过改变曲线上型值点的位置和个数以及每个型值点处的权因子可达到预期的变形效果.实验表明,该方法数学背景简单、易于控制,重复使用可获得丰富的变形效果,适用于几何造型和计算机动画等领域.  相似文献   

10.
利用调和映射的平面和球面中值性质,提出了确定点模型曲面参数化映射中有关权因子的两种新方法,设计了能够达到内在变形较小的相应参数化方法,并将参数化方法应用于点模型曲面上的纹理映射.实验和统计结果表明,文中方法是比较有效的点模型曲面的参数化方法.  相似文献   

11.
This paper proposes a new cell intuition simulation method which is a combination of intuitive simulation calculation method and the operation of binary image, and applied it in the innovation of the graphic design process. First of all, we study how to express a variety of graphics, and establish the definition of cell intuitive model, work out the cell intuitive operation process and many new cellular operators such as a variety of matrix blocks crossover operator, a variety of matrix blocks mutation operator, matrix blocks replace operator, matrix blocks compression operator, matrix blocks extension operator. By choosing two or more cells and selecting the artificial selection or fitness selection, we can set up and visualize the design and pick the best design results .Finally, validation is made on this algorithm by an example, and a innovation graphic is also represented.  相似文献   

12.
Shape Modification and Deformation of Parametric Surfaces   总被引:2,自引:0,他引:2  
A new method for shape modification or deformation of all kinds of parametric surfaces is presented. Instead of using any control mesh and designing any auxiliary tools for modification or deformation, this method only needs to multiply the equation of the original surface by several shape operator matrixes so that deformation effects are achieved. Due to introducing interactive control parameters with different properties those parameters can be changed to get more ideal effects of deformation or shape modification. The core of the method is that so-called cosine extension function is proposed by which the shape operator matrix can be created. Experiment shows that the method is simple, intuitive and easy to control, and diversified local deformations or shape modifications can easily be made via small and random variations of interactive control parameters.  相似文献   

13.
基于区间数型多因素指派模型的多传感器优化分配方法   总被引:1,自引:0,他引:1  
如何在不确定的复杂环境下优化分配有限的传感器资源是传感器管理系统中的一个关键问题.在用区间数来描述这种不确定性研究思路的基础上, 提出了一种新的区间数型多因素指派模型的求解方法. 首先, 给出了拓展的区间数型多因素指派模型. 然后, 采用不确定有序加权平均 (Uncertain ordered weighted average, UOWA) 算子集结规范化后的区间数型效率矩阵, 通过逼近理想解的排序法 (Technique for order preference by similarity to ideal solution, TOPSIS) 确定综合效率矩阵. 进一步将其转化为标准型指派问题, 最后通过匈牙利法得到最优解. 通过算例说明了该方法解决多传感器优化分配问题的有效性.  相似文献   

14.
The arithmetic operator method (AOM) is a method for performing arithmetic operations on one or more signals that are described by their spectra. By extension, any analytic functional operation on the signals can be performed in the frequency domain using matrix‐vector operations. The mathematical foundation of AOM is presented as a numerically efficient convolution‐like procedure in this article. It is directly applicable to the behavioral modeling of nonlinear RF and microwave circuits and systems. © 2003 Wiley Periodicals, Inc. Int J RF and Microwave CAE 13, 473–495, 2003.  相似文献   

15.
In this paper, a new parallel adaptive self-tuning recursive least squares (RLS) algorithm for time-varying system identification is first developed. Regularization of the estimation covariance matrix is included to mitigate the effect of non-persisting excitation. The desirable forgetting factor can be self-tuning estimated in both non-regularization and regularization cases. We then propose a new matrix forgetting factor RLS algorithm as an extension of the conventional RLS algorithm and derive the optimal matrix forgetting factor under some reasonable assumptions. Simulations are given which demonstrate that the performance of the proposed self-tuning and matrix RLS algorithms compare favorably with two improved RLS algorithms recently proposed in the literature.  相似文献   

16.
17.
Fuzzy game theory has been applied in many decision-making problems. The matrix game with interval-valued intuitionistic fuzzy numbers (IVIFNs) is investigated based on Archimedean t-conorm and t-norm. The existing matrix games with IVIFNs are all based on Algebraic t-conorm and t-norm, which are special cases of Archimedean t-conorm and t-norm. In this paper, the intuitionistic fuzzy aggregation operators based on Archimedean t-conorm and t-norm are employed to aggregate the payoffs of players. To derive the solution of the matrix game with IVIFNs, several mathematical programming models are developed based on Archimedean t-conorm and t-norm. The proposed models can be transformed into a pair of primal–dual linear programming models, based on which, the solution of the matrix game with IVIFNs is obtained. It is proved that the theorems being valid in the exiting matrix game with IVIFNs are still true when the general aggregation operator is used in the proposed matrix game with IVIFNs. The proposed method is an extension of the existing ones and can provide more choices for players. An example is given to illustrate the validity and the applicability of the proposed method.  相似文献   

18.
This paper presents an incremental approach to automatic algorithm design,which can be described by algebraic specifications precisely and conveniently.The definitions of selection operator and extension operator which ca be defined by strategy relations and transformations are given in order to model the process of finding the solution of a problem.Also discussed is its object-oriented implementation.The functional specification and the design specification for an algorithm are given in one framework so that the correctness of the algorithm can be easily proved.  相似文献   

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