<?xml version="1.0" encoding="UTF-8"?>
<article article-type="Research Article">
  <front>
    <journal-meta>
      <journal-id journal-id-type="publisher">journal-of-dynamical-systems-and-geometric-theories</journal-id>
      <journal-title-group>
        <journal-title>Journal of Dynamical Systems and Geometric Theories</journal-title>
      </journal-title-group>
      <issn publication-format="electronic">2169-0057</issn>
      <issn publication-format="print">1726-037X</issn>
      <publisher>
        <publisher-name>Taru Publications</publisher-name>
      </publisher>
    </journal-meta>
    <article-meta>
      <article-id pub-id-type="doi">10.1080/1726037X.2021.2009199</article-id>
      <title-group>
        <article-title>Rotational Entropy of an Annular Iterated Functions System</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author" corresp="yes">
          <name>
            <surname>Rezaei</surname>
            <given-names>Fatemeh</given-names>
          </name>
          <aff>Department of Mathematics, Yazd University, Iran</aff>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Nia</surname>
            <given-names>Mehdi Fatehi</given-names>
          </name>
          <aff>Department of Mathematics, Yazd University, Iran</aff>
        </contrib>
      </contrib-group>
      <volume>19</volume>
      <issue>2</issue>
      <fpage>189</fpage>
      <lpage>202</lpage>
      <pub-date date-type="pub">
        <day>04</day>
        <month>01</month>
        <year>2022</year>
      </pub-date>
      <abstract>
        <p>In this article, we consider an iterated functions system (IFS) whose functions are homeomorphisms on an annulus. We define rotational spanning and separating sets for the IFS and then provide two definitions for the rotational entropy of the IFS. We show that in the IFSs, the rotational entropy is a topological invariant. We prove that the rotational entropy of an annular IFS is equal to the rotational entropy on its non-wandering set for sequences of functions with a specific condition.</p>
      </abstract>
      <kwd-group>
        <kwd>Rotational entropySpanning setSeparating setTopological invariantNon-wandering set</kwd>
      </kwd-group>
      <custom-meta-group>
        <custom-meta>
          <meta-name>access</meta-name>
          <meta-value>open</meta-value>
        </custom-meta>
        <custom-meta>
          <meta-name>retracted</meta-name>
          <meta-value>no</meta-value>
        </custom-meta>
      </custom-meta-group>
    </article-meta>
  </front>
</article>
