摘要
本文研究了单位球上的Q_p空间中的de la Vallée Poussin平均算子,并通过高阶光滑模来建立Jackson逼近定理.此外,我们还得到了Bernstein不等式,K-泛函和光滑模的等价刻画等结果.
In this paper, we introduce the de la Vallee Poussin means on the unit ball of C~n and establish in Q_p spaces the Jackson's approximation theorem in terms of the higher orders of modulus of smoothness, the Bernstein type inequalities, and the equivalence characterization between modulus of smoothness and K-functional.
引文
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