Determination of jumps in terms of derivative convolution operators.

X. L. Shi and W. Wang [12] studied the question on determination of jumps for functions via conjugate convolution operators. In the present paper a different way to calculate jumps is discussed. We show that derivative convolution operators can be used to determine jumps for functions. Furthurmore, we point out that the assumption ' ϕ is even' in Shi-Wang's theorem can be removed. [ABSTRACT FROM AUTHOR]