劉蕊蕊,胡曉敏,吳華亭
(杭州電子科技大學數(shù)學研究所,浙江 杭州 310018)
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一類修正的q-Baskakov-Beta算子的逼近性質(zhì)
劉蕊蕊,胡曉敏,吳華亭
(杭州電子科技大學數(shù)學研究所,浙江 杭州 310018)
q-Baskakov-Beta算子作為q-Baskakov算子的變形算子具有許多優(yōu)良的性質(zhì).介紹了一類新的修正的q-Baskakov-Beta算子,通過計算得出了該算子的各階矩,并討論了其矩估計;研究了該算子的逼近性質(zhì),證得該算子有界且收斂.
q-Baskakov-Beta算子;K-泛函;光滑模;逼近
Baskakov算子作為算子逼近的一個重要分支,在函數(shù)逼近論中占有重要地位,已有大量的研究成果.近年來,文獻[1]提出了q-Baskakov算子,并研究了該算子的逼近性質(zhì).在此之后,很多學者對q-Baskakov算子進行研究,得出了其變形算子,文獻[2]在文獻[3]的基礎上首先提出了q-Baskakov-Beta算子.本文是在文獻[2]的基礎上,給出一類修正的q-Baskakov-Beta算子,采用文獻[4]中相同的證明方法對其逼近性質(zhì)進行了研究,得出了該算子具有有界性和收斂性.
(1)
K-泛函[6]為:
(2)
(3)
本文主要討論定義4中修正的q-Baskakov-Beta算子的逼近性質(zhì),先看一些引理.
證明由定義4可知
本文在文獻[2]的基礎上,給出了一類新的修正的q-Baskakov-Beta算子,利用K-泛函和光滑模研究了該算子的逼近性質(zhì),拓展了對一般的q-Baskakov-Beta算子的認識,為進一步研究這類修正型的算子有一定的意義.
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Approximation Properties of the Modified q-Baskakov-Beta Operators
LIU Ruirui, HU Xiaomin, WU Huating
(InstituteofMathematics,HangzhouDianziUniversity,HangzhouZhejiang310018,China)
The q-Baskakov-Beta operators have many better properties as the deformation of the q-Baskakov operators. This paper introduces a new modified q-Baskakov-Beta operators, gets the moments of this operators by calculating, and the moments estimation is discussed. It also investigates some kind of approximation properties of the operators, and gets that this operators with bounded and convergence.
q-Baskakov-Beta operators; K-functional; modulus of smoothness; approximation
10.13954/j.cnki.hdu.2016.05.020
2015-12-11
劉蕊蕊(1990-),女,河南周口人,碩士研究生,函數(shù)逼近論.通信作者:胡曉敏副教授:E-mail:mathhuxm@163.com.
O174.41
A
1001-9146(2016)05-0099-04