A function is called an exponential if it is a linear combination of products of polynomials with pure exponentials. In this paper lower and upper bounds for families of spaces of piecewise exponentials are established. In particular, the exact Lp-approximation order (1 _< p _<) is found for a family {Sh}h>O of function spaces when each Sh is generated by an exponential box spline and its multi...

This paper points out that the fundamental partial differential equation (PDE) implies that the drifts of the underlying processes are irrelevant, regardless whether the state factors are tradable or not. Since the simple boundary condition for default-free discount bonds can be satisfied by a linear discount function, the variances and covariances of the underlying processes are also irrelevan...

Both the 4-point and the uniform cubic B-spline subdivisions double the number of vertices of a closed-loop polygon P and produce sequences of vertices fj and bj respectively. We study the J-spline subdivision scheme Js, introduced by Maillot and Stam, which blends these two methods to produce vertices of the form vj=(1–s)fj+sbj. Iterative applications of Js yield a family of limit curves, the ...

Arbitrary ratio sampling rate conversion (SRC) structure using B-spline interpolation is proposed for software defined radio (SDR) in this paper. By combining SRC with SDR’s transmitter/receiver filter, the constraint on SRC reconstruction filter can be relaxed, and an overall computational reduction can be achieved. The mixedwidth B-spline is introduced so that both antiimaging and anti-aliasi...

In applications that involve interactive curve and surface modeling, the intuitive manipulation of shapes is crucial. For instance, user interaction is facilitated if a geometrical object can be manipulated through control points that interpolate the shape itself. Additionally, models for shape representation often need to provide local shape control and they need to be able to reproduce common...

Wave equation is one of the second order linear hyperbolic equation. Telegraph as a special case wave has interesting point to investigate in numerical view. In this paper, we consider methods for dimensional telegraph by using cubic B-spline collocation method. Collocation method solve partial differential model problem. Cubic spline interpolation an third polynomial. This polynomial interpola...

In this paper, we are interested in giving bounds for exponential sums over certain curves defined over Galois rings. We first define summation subsets as the images of lifts of affine pieces of the reduced curve, and most of the work is devoted to giving bounds for the degrees of their defining functions. Then we get bounds for exponential sums, generalizing results of Kumar et al., Winnie Li ...

this paper describes an approximating solution, based on lagrange interpolation and spline functions, to treat functional integral equations of fredholm type and volterra type. this method can be extended to functional dierential and integro-dierential equations. for showing eciency of the method we give some numerical examples.

in this paper, we present an edge detection method based on wavelet transform and hessian matrix of image at each pixel. many methods which based on wavelet transform, use wavelet transform to approximate the gradient of image and detect edges by searching the modulus maximum of gradient vectors. in our scheme, we use wavelet transform to approximate hessian matrix of image at each pixel, too. ...