In order to eliminate the weakness of large volumes data in 3D modeling process, a fast and efficient sampling method based on curvature analysis of cubic Bézier curve is presented. With the method, the characteristic points and curvature maximum value of cubic Bézier curve are used as the reference standard of the sampling interval and density. For cubic B-spline curves, the sampling data can ...

A comparison between experimental and theoretical electron Energy Loss Near Edge Structure (ELNES) of B and N K-edges in cubic boron nitride is presented. The electron energy loss spectra of cubic boron nitride particles were measured using a scanning transmission electron microscope. The theoretical calculation of the ELNES was performed within the framework of density functional theory includ...

The isolation intervals of the real roots symbolic monic cubic polynomial p ( x ) = 3 + a 2 b c $p(x) x^3 ax^2 bx c$ are found in terms simple functions coefficients (such as − $-a$ , / $-a/3$ $-c/b$ ± $\pm \sqrt {-b}$ when $b$ is negative), and some auxiliary quadratic equations whose also cubic. A much-improved complete root classification, addressing signs (together with giving intervals) in...

B-spline functions play important roles in both mathematics and engineering. To describe a numerical method for solving the boundary value problem of linear ODE with second-order by using B-spline. First, the cubic B-spline basis functions are introduced, then we use the linear combination of cubic B-spline basis to approximate the solution. Finally, we obtain the numerical solution by solving ...

We consider diagonal cubic surfaces defined by an equation of the form ax + by + cz + dt = 0. Numerically, one can find all rational points of height 6 B for B in the range of up to 10 , thanks to a program due to D. J. Bernstein. On the other hand, there are precise conjectures concerning the constants in the asymptotics of rational points of bounded height due to Manin, Batyrev and the author...

Based on variational properties, we generalize the approximation properties of the univariate natural cubic spline to splines in arbitrary dimensions. In one dimension, the solution of the variational problem { given a = x1 < · · · < xN = b and values f(x1), . . . , f(xN ) in R, find a function s with s(xi)=f(xi), i=1, . . . ,N , that minimizes ‖s‖L2([a,b]) is given by the natural univariate cu...

In this paper, we propose a new multilevel univariate approximation method with high order accuracy using radial basis function interpolation and cubic B-spline quasi-interpolation. The proposed approach includes two schemes, which are based on radial basis function interpolation with less center points, and cubic B-spline quasi-interpolation operator. Error analysis shows that our method produ...