多项式逼近与二十年后的$ω^r_ϕ(f,t)$
Polynomial Approximation and $ω^r_ϕ(f,t)$ Twenty Years Later
摘要：
大约二十年前，光滑性测度$ω^r_ϕ(f,t)$被引入，并且与多项式逼近的速率有关。在这篇文章中，我们调查了自那时以来关于这一点和相关概念的发展。
英文摘要：
About twenty years ago the measure of smoothness $ω^r_ϕ(f,t)$ was introduced and related to the rate of polynomial approximation. In this article we survey developments about this and related concepts since that time.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
