Strong Converse Inequality for Szász Operators  

作　　者：LIU Li-xia YANG Ge GUO Shun-sheng 

机构地区：[1]College of Mathematics and Information Science, Hebei Normal University, Hebei 050016, China

出　　处：《Journal of Mathematical Research and Exposition》2008年第1期147-155,共9页数学研究与评论（英文版）

基　　金：the National Natural Science Foundation of China （No. 10571040）; the Natural Science Foundation of Hebei Province （No. A2004000137）; the Doctorial Fund of Education Department of Hebei Province （No. B2004118）; the Doctorial Fund of Hebei Normal University （No. L2003B04）.

摘　　要：In this paper, we obtain the strong converse inequality for Száisz operators with K-functional by introducing a new K-functional of the formKλ^α（f,t^2） =inf g∈Cλ^2{‖f -g‖o ＋t^2‖g‖2} （0 ≤ λ≤ 1,0 ≤α ≤ 2）,where ‖· ‖o, ‖· ‖2,Cλ^2 are defined in the paper. As for its applications, we have extended some results before this paper.In this paper, we obtain the strong converse inequality for Száisz operators with K-functional by introducing a new K-functional of the formKλ^α（f,t^2） =inf g∈Cλ^2{‖f -g‖o ＋t^2‖g‖2} （0 ≤ λ≤ 1,0 ≤α ≤ 2）,where ‖· ‖o, ‖· ‖2,Cλ^2 are defined in the paper. As for its applications, we have extended some results before this paper.

关 键 词：strong converse inequality Szász operators Ditzian modulous. 

分 类 号：O174.41[理学—数学]