This paper develops a new way to create smooth piecewise polynomial free-form spline surfaces from quadmeshes that include T-junctions, where surface strips start or terminate. All mesh nodes can be interpreted as control points of geometrically-smooth, piecewise polynomials that we call GT-splines. GT-splines are B-spline-like and cover T-junctions by two or four patches of degree bi-4. They c...

We construct a polynomial spline similar to the box spline, except that we relax the condition that its knots are spaced uniformly in each direction. The recurrence relation for this spline is a generalization of the recurrence relations for the box spline and univariate B-spline. The construction generalizes to exponential-polynomial splines [5]. §

In both applications and wavelet theory, the spline wavelets are especially interesting, in part because of their simple structure. In a previous paper we proved that the function m;l is an m th order spline wavelet having an l th order spline dual wavelet. This enabled us to derive biorthogonal spline wavelet bases. In this paper we rst study the general structure of cardinal spline wavelets, ...

A personal account of the author's encounters with multivariate splines during their early history. 1 Tensor product spline interpolation My first contact with multivariate splines occurred in August 1960. In my first year at the Harvard Graduate School, working as an RA for Garrett Birkhoff, I had not done too well but, nevertheless, had gotten married and so needed a better income than the RA...

The paper discusses asymptotic properties of penalized spline smoothing if the spline basis increases with the sample size. The proof is provided in a generalized smoothing model allowing for non-normal responses. The results are extended in two ways. First, assuming the spline coefficients to be a priori normally distributed links the smoothing framework to generalized linear mixed models (GLM...

We describe a method to construct a hierarchical representation of a given implicitly defined algebraic spline curve with the help of weighted spline wavelets. These wavelets are adapted to the region of interest, in our case to the region along the curve, by means of a weighted inner product. The application of two different types of weighted spline wavelets is considered and compared with sta...

In this paper we study the sensitivity of a spline function, represented in terms of Bsplines, to perturbations of the knots. We do this by bounding the difference between a primary spline, and a secondary spline with the same B-spline coefficients, but different knots. We give a number of bounds for this difference, both local bounds and global bounds in general L-spaces. All the bounds are ba...

An algorithmic approach to degree reduction of interval B-spline curve is presented in this paper. The curves that are useful in geometric modeling should have a relatively smooth shape and should be intuitively connected with the path of the sequence of control points. One family of curves satisfying this requirement is represented by the B-spline curves. The four fixed Kharitonov's polynomial...