1)NURBS非均匀有理B样条曲线
英文短句/例句
1.Effective non-uniform rational B-spline interpolator based on look-ahead algorithm基于前瞻算法的高效非均匀有理B样条曲线插补器
2.NURBS (Non-Uniform Rational B-Splines)不均匀有理B样条曲线
3.Research on Surface Reconstruction Based on Nou-Uniform Rational B-Spline;基于非均匀有理B样条(NURBS)的曲面反求的研究
4.AN UNEVEN ALGORITHM FOR THE SUBDIVISION OF RATIONAL BE ′[DD)〗ZIER CURVES有理bézierb>曲线b>的非均匀细分算法
5.DISPLAY ALGORITHE AND IMPLEMENT OF NURBS CURVE;非均匀B样条曲线的快速显示算法与实现
6.Multiresolution Editing of Curves Based on Non-Uniform B-Spline Wavelets基于非均匀B样条小波的曲线多分辨编辑
7.Constructing and processing of NC instruction for 5-axis machining of NURBS surfaces非均匀有理B样条曲面五轴加工数控指令的构建与处理
8.Uniform duplicate mixed hyperbolic polynomial B-spline curves均匀二重混合双曲多项式B样条曲线
9.WEIGHTS OPTIMIZATION FOR FAIRING CUBIC UNIFORM RATIONAL B SPLINE CURVES三次均匀有理B样条曲线的权因子优化光顺算法
10.Ship Body Meterage Based on NURBS;基于非均匀有理B样条的船体分段测量
11.Design of Spatial Cam Based on Non-uniform Rational B-splines基于非均匀有理B样条的空间凸轮设计
12.NURB surfacesNURBS(非一致有理B样条曲线)
13.Arbitrary Resolution Fairing of Quasi-Uniform Cubic B-Spline Curve准均匀三次B样条曲线的任意分辨率光顺
14.A Class of Cubic Uniform B-spline Curve with Shape Parameters一类带形状参数的三次均匀B样条曲线
15.3D reconstruction of digital female pelvic model based on NURBS surface基于非均匀有理B样条的女性盆腔三维数字化模型的构建
16.Curvature monotony condition Tor the quadratic rational B spline curves.二次有理B样条曲线曲率单调条件
17.Based on the Weighted Constrained Optimization of the Three-uniform B-spline Curve Shape Modification基于加权约束优化的三次准均匀B样条曲线修改
18.Construction of a Non-uniform Triviariate S_4~2 B-Spline;一个非均匀三元S_4~2 B-样条的构造
相关短句/例句
non uniform rational B spline非均匀有理B-样条曲线
3)Non-Uniform Bational B-Spline非均匀有理样条B样条曲线
4)non-uniform rational B-spline surface非均匀有理B样条曲面
1.Interpolation for non-uniform rational B-spline surface based on STEP-NC;为提高曲面的加工效率和精度,提出了一种基于STEP-NC的非均匀有理B样条曲面加工方法。
5)Non-Uniform Rational B-Splines(NURBS) curves and surfaces非均匀有理B样条曲线曲面
6)non-uniform α-B splineα-非均匀B样条曲线
延伸阅读
B样条曲线B样条曲线B-spline curve B yangtiQO qUxlanB样条曲线(BsPline curve)用B样条函数构造的曲线。B样条函数在19世纪初首先由N.肠bachevsky提出。1946年,1.J.段hoenbe唱用B样条函数光滑统计数据,并提出B样条近似理论。1972年,deB刀r,M.Cox,L.Mal侣field等人发现了B样条函数的递归关系,1974年,C心rdon和Ri~-feld用B样条的递归性质构造了B样条曲线。它除保持了决对er曲线的直观性和凸包性等优点之外,还可以进行局部修改,且曲线更逼近特征多边形。同时,曲线的阶次也与顶点数无关,因而更方便灵活。由于以上原因,B样条曲线得到越来越广泛的应用。 参照3戈ier曲线公式,已知n十1个控制点尸、(i二0,1,…,n)为特征多边形的顶点,K阶(K一1次)B样条曲线的表达式是:c(。)=艺尸八,*(。),其中从,*(u)是B样条调和函数,也称之为B样条基函数,按照递归公式可定义为:Ni,1(u)={‘若“镇“蕊‘、·‘(O其它(1)从,*(u)_(u一t,)从,;一1(u) t£+无--一t乞十业生丝卫些型己上:亘全些 t£+走一ti+1 t*一1镇u(t,+i其中t‘是节点值,T=「t。,tl,…,t:+2*]构成了K阶B样条函数的节点矢量,其中的节点是非减序列,且L二n一k+1。当节点沿参数轴作均匀等距分布(即t泛十1一t*二常数)时,则为均匀B样条函数。当节点沿参数轴的分布不等距时,即(t,+1一t,)护常数时,则表示非均匀B样条函数。 B样条曲线有如下性质: (1)局部性k阶B样条曲线只被相邻的K个顶点所控制,而与其它顶点无关。图1所示是一条均匀B样条曲线。由图可见尸5变化时只对其中一段曲线有影响。 (2)连续性B样条曲线在t、(k+1(i毛n)处公*1,4(u)=Nl,4(u)只+NZ,;(u)只十1+ N3,4(u)只+:+N4,4(u)只+3故第i段三次B样条曲线(见图2)可写成:C£·4(u)一置妈,4(u)只·厂2PI+: 图2对应的矩阵式是三次B样条曲线111,|||11|刘 一++(1/6)[u3 3一3一63 03 41从21飞阵0}…p‘0{{只田比u任[0,1],i=1,2,…,n一2有Q重节点的连续性不低于(k一Q一l)阶。整条曲线C(u)的连续性不低于(k一Q~一l)阶,其中Q~是在区间(红,t,十1)内的最大重节点数。
