Ulyanov inequalities for the mixed moduli of smoothness in mixed metrics
In this paper we prove Ulyanov-type inequalities between mixed moduli of smoothness of positive orders in different metrics.
math.FA↗
arXiv subjects
Publications and source records attributed to B. V. Simonov.
In this paper we prove Ulyanov-type inequalities between mixed moduli of smoothness of positive orders in different metrics.
In this paper we survey recent developments over the last 25 years on the mixed fractional moduli of smoothness of periodic functions from $L_p$, $1<p<\infty$. In particular, the paper includes monotonicity properties, equivalence and realization results, sharp Jackson, Marchaud, and Ul'yanov inequalities, interrelations between the moduli of smoothness, the Fourier coefficients, and "angular" approximation. The sharpness of the results presented is discussed.