查询词典 interpolating spline function

Secondly, two physical models were constructed, which could model rough surface and describe the features of the earth surface, such as chine, neck, valley and hill, etc. According to difference method, the ""true"" volume of the physical models were measured, which was 13260cm3 and regarded as the analysis foundation of the precision of the volume that was calculate by DEM. The discrete dada of the models on a regular spacing of 1cm were collected by 3SPACE FASTRAK and the DEM was obtained by interpolating the discrete dada through GIS software. Based on the volume of the models calculated by DEM, different interpolating methods (IDW, Spline, Natural Neighbor, and Kriging) and variation of grid spacing of data were compared and their effects on precision of volume calculation were analyzed.

构建了可模仿凸凹不平地形表面的实体模型，该模型能够表征山脊、山尖、山涧、丘陵等地形特征；根据体积差减法测量实体模型的体积作为数据精度分析的体积&真值&，该值为13260cm~3，作为采用DEM进行体积计算的基准值；利用精度为0.08cm的三维数字化仪采集间距为1cm的离散数据点，对离散数据点用GIS软件进行内插处理生成DEM模型，通过DEM计算出模型的体积，探讨不同内插方法(IDW、Spline、Natural Neighbor和Kriging)和数据格网间距变化对体积计算精度的影响。

By a more precise estimation of maximum value of a B-spline basis function and utilizing of the local support property of B-spline basis function, the control points of a set of compatible B-spline curves are reduced, which makes the skinning algorithm more effective.

对B样条基函数的最大值进行了更为精确的估计，并且充分利用B样条基函数的局部支撑性，尽可能多地删除相容性处理后B样条曲线的控制点，使得蒙皮算法更加有效。

The basic idea is as follows: first, a kind of plane α-B-spline interpolation curve with a shape control parameter a is constructed; then, by converting the first derivatives of the curve into Bernstein polynomial, the positive conditions of Bernstein polynomial can be used to get the necessary and sufficie nt conditions for the monotonicity of α-B-spline interpolation curves, i.e., the range of the parameter a. Therefore, monotone-preserving interpolating curves can be obtained succinctly.

其基本思想是：首先构造带有形状可调参数的一类平面(-B样条插值曲线，再把其一阶导矢的两个分量分别转化为Bernstein多项式，从而利用Bernstein多项式的正性条件，得到此曲线为单调的充要条件，即形状参数的取值范围，简单、快捷地实现此参数样条曲线的保单调插值。

The given method takes the Hermite interpolation curvcs and the cubic non-uniform B-spline curves as the special cases and unifies the representation of the curves interpolating the control polygon and the cubic non-uniform B-spline curves approximating the control polygon.

所给方法以Hermite型插值曲线和非均匀三次B样条曲线为特殊情形，将插值于控制点的曲线和逼近于控制多边形的非均匀B样条曲线统一起来。

Lastly,we present an algorithm to isolate real roots of a univariate spline, i.e., computing asequence of disjoint intervals such that each of them contains exactly one real root of agiven spline function, which is primarily based on the use of Descartes\' rule of signs withits B-spline coefficients and de Casteljau algorithm of B?

最后，基于B-样条系数的Descartes符号准则和Bézier曲线的de Casteljau算法，我们给出了一元样条实根分离算法，也就是计算出一列不相交区间，使得每个区间恰好只包含此样条函数的一个实根。

Lastly,we present an algorithm to isolate real roots of a univariate spline, i.e., computing asequence of disjoint intervals such that each of them contains exactly one real root of agiven spline function, which is primarily based on the use of Descartes rule of signs withits B-spline coefficients and de Casteljau algorithm of Bzier curve.

最后，基于B-样条系数的Descartes符号准则和Bézier曲线的de Casteljau算法，我们给出了一元样条实根分离算法，也就是计算出一列不相交区间，使得每个区间恰好只包含此样条函数的一个实根。

The new methodof defining spline function will generalize the concept to the more universal Hilbert space. Hence, we take into consideration the interpolation spline function, general linear differential operater in semi- open interval and the Green function defined accordingly, and the reproducing kernel to produce the Green function and prove the existence of the reproducing kernel.

采用了一种新的样条函数的定义方法，把样条函数的概念推广到更一般的Hilbert空间上，再考虑半开闭区间a，+∞上的插值样条函数，一般线性微分算子及其定义的Green函数和再生核，构造出Green函数并且证明了再生核的存在性。

A kind of method to determine boundary conditions of interpolating quadric spline function with halfknots as conjunction points, which is C 1 continuous but its second derivative function is piecewise constant, is obtained by means of least squares.

鉴于此，本文利用最小二乘法，获得了一种半节点二次插值样条边界条件确定方法，该方法可以保证二次插值样条在半节点处二阶导数的变化最小，这相当于保证了曲率的变化最小。

Algebraic curve is commonly used in CAGD. Traditional curve interpolation is in various forms of spline fuction. Although better result can be obtained by spline curve, the former two of elliptic, hyperbolic and parabolic shapes can not be represented by spline curve. An exploring research in this aspect is made in this thesis.

代数曲线是CAGD中经常用到的曲线，以往的曲线插值基本上是采用样条函数的形式，采用这种形式虽然能够获得很好的效果，但样条函数所能表达的形状都是抛物线型，对椭圆型与双曲线型曲线的表示是无能为力的。

In this paper,the B-spline curve is supposed as boundary curves,when they are in two paralled plane and two arbitrary plane,the condition about the control vertex of characteristic polygon when the ruled surface is developable are gained,solved the designing problem of degree and degree B-spline curve .Throughing (2,3) degree and (2,2) degree B-spline ,we haveproved the validity and utility of this method.

本文用两条B样条曲线作边界曲线，当它们位于两平行平面上和两任意平面上时，研究得到了由它们形成的直纹面为可展面时它们的特征多边形顶点满足的条件，解决了(n，n+1)次和次可展B样条曲面的设计问题，然后以(2，3)次和(2，2)次B样条曲面为构造实例，证明了该算法的正确性和实用性。

Aquatic or marsh-growing fern allies; known to have existed since the Cenozoic; sometimes included in Lycopodiales.

生活于水中或湿地的蕨类；从新生代生存至今；有时归于石松目之中。

The engine was uprated from a 90hp Franklin to a 125hp Lycoming.

改良过的引擎是从90hp到125hp莱康明富兰克林。