## SEARCH

#### Institution

##### ( see all 341)

- Beijing Normal University 41 (%)
- Hangzhou University 22 (%)
- Peking University 20 (%)
- Zhejiang University 20 (%)
- Nanjing University 16 (%)

#### Author

##### ( see all 509)

- Dachun, Yang 11 (%)
- Shanzhen, Lu 9 (%)
- Yingguang, Shi 9 (%)
- Yongping, Liu 8 (%)
- Guoen, Hu 7 (%)

## CURRENTLY DISPLAYING:

Most articles

Fewest articles

Showing 1 to 10 of 490 matching Articles
Results per page:

## The polya-1 property for convex approximation

### Approximation Theory and its Applications (1990-12-01) 6: 9-17 , December 01, 1990

If f∈L_{p}[0, 1], let f_{p} be its best L_{p}-approximant by convex functions. It is shown that if
$$f \in \mathop \cup \limits_{p > 1} L_p [0,1], then \mathop {lim}\limits_{p \to 1} f_p (x)$$
exists uniformly on closed subintervals of (0,1).

## Scattered data interpolation by bivariate C1-piecewise quadratic functions

### Approximation Theory and its Applications (1990-09-01) 6: 6-29 , September 01, 1990

In this paper, we propose a completely local scheme based on continuously differentiable quadratic piecewise polynomials for interpolating scattered positional data in the plane, in such a way that quadratic polynomials are reproduced exactly. We present some numerical examples and applications to contour plotting.

## About the Fourier transforms of non-smooth measures on hyperspheres

### Approximation Theory and its Applications (1995-03-01) 11: 10-15 , March 01, 1995

If d_{μ} is the Fourier transform of a smooth measure d_{μ} on the hypersphere S^{n−1} (n≥2) then there exists a constant C dependent only on n such that ⋎d_{μ}(y)⋎≤C(1+⋎y⋎)^{−(n−1)/2} for all y∈R^{n}. In this paper, we show that the above statement is false for non-smooth measures. And we present the corresponding estimations for the Fourier transforms of certain non-smooth measures on S^{n−1}.

## A note on a strong uniqueness theorem of strauss

### Approximation Theory and its Applications (1995-03-01) 11: 1-5 , March 01, 1995

In this paper we present a correction of the proof of a strong uniqueness theorem given by H. Strauss^{[1]} in 1992 on approximation by reciprocals of functions of an n-dimensional space (u_{1}, … u_{n}) satisfying coefficient constraints.

## Average σ-K widths of some generalized Sobolev-Wiener classes

### Approximation Theory and its Applications (1992-12-01) 8: 79-88 , December 01, 1992

In this paper, a kind of generalized Sobolev-Wiener classes $$W_{pq}^r ({\text{R}},h),h > 0$$ , h>0, defined on the whole real axis, is introduced, and the average σ-K width problem of these function classes in the metric $$W_{pq}^r ({\text{R}},h),h > 0$$ is studied. For the case p=+∞, 1≤q≤+∞, the case 1≤p <+∞, q=1, we get their exact values and identify their optimal subspaces.

## Numerical resolvent methods for constrained problems in mechanics

### Approximation Theory and its Applications (1996-12-01) 12: 1-25 , December 01, 1996

Resolvent methods are presented for generating systematically iterative numerical algorithms for constrained problems in mechanics. The abstract framework corresponds to a general mixed finite element subdifferential model, with dual and primal evolution versions, which is shown to apply to problems of fluid dynamics, transport phenomena and solid mechanics, among others. In this manner, Uzawa’s type methods and penalization-duality schemes, as well as macro-hybrid formulations, are generalized to non necessarily potential nonlinear mechanical problems.

## On approximation of classes of functions for modified Szasz operators

### Approximation Theory and its Applications (1992-12-01) 8: 61-65 , December 01, 1992

In this note, using some results of the probability theory we obtained some estimates of the approximation of classes of functions for modified Szasz operators with regard to two special classes of functions.

## Some constructive properties of functions defined on the sphere

### Approximation Theory and its Applications (2000-03-01) 16: 26-35 , March 01, 2000

The norm of difference operators for functions defined on the sphere is investigated. A mistake in Rustamov's results is pointed out by a counterexample. And correct result is given.

Results of convergence in norm of difference operators acting on the differentiable functions on the sphere are obtained. The highest possible degree tending to zero for the moduli of continuity of fractional order for non-constant valued functions are discussed.

## Approximation of continuous functions by generalized karamata means

### Approximation Theory and its Applications (1994-03-01) 10: 88-98 , March 01, 1994

A sufficient condition for the order of approximation of a continuous 2π periodic function with a given majorant for the modulus of continuity by the [F, d_{n}] means of its Fourier series to be of Jackson order is obtained. This sufficient condition is shown to be not enough for the order of approximation by partial sums of their Fourier series to be of Jackson order. The error estimate is shown to be the best possible.

## Application of Chebyshev sets to multiproducts

### Approximation Theory and its Applications (1993-03-01) 9: 76-81 , March 01, 1993

In this paper we give some new Chebyshev sets and their applications to multiproducts.