Displaying 21 – 40 of 558

Showing per page

On a higher-order Hardy inequality

David Eric Edmunds, Jiří Rákosník (1999)

Mathematica Bohemica

The Hardy inequality Ω | u ( x ) | p d ( x ) - p x ¨ c Ω | u ( x ) | p x ¨ with d ( x ) = dist ( x , Ω ) holds for u C 0 ( Ω ) if Ω n is an open set with a sufficiently smooth boundary and if 1 < p < . P. Hajlasz proved the pointwise counterpart to this inequality involving a maximal function of Hardy-Littlewood type on the right hand side and, as a consequence, obtained the integral Hardy inequality. We extend these results for gradients of higher order and also for p = 1 .

On a new kind of 2-periodic trigonometric interpolation

Tianzi Jiang, Songde Ma (1996)

Applications of Mathematics

It is well-known that the interpolation theory plays an important role in many fields of computer vision, especially in surface reconstruction. In this paper, we introduce a new kind of 2-period interpolation of functions with period 2 π . We find out the necessary and sufficient conditions for regularity of this new interpolation problem. Moreover, a closed form expression for the interpolation polynomial is given. Our interpolation is of practical significance. Our results provide the theoretical...

On a Problem of Best Uniform Approximation and a Polynomial Inequality of Visser

M. A. Qazi (2014)

Bulletin of the Polish Academy of Sciences. Mathematics

In this paper, a generalization of a result on the uniform best approximation of α cos nx + β sin nx by trigonometric polynomials of degree less than n is considered and its relationship with a well-known polynomial inequality of C. Visser is indicated.

Currently displaying 21 – 40 of 558