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	<updated>2026-10-21T02:45:57Z</updated>
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	<entry>
		<id>https://en.formulasearchengine.com/w/index.php?title=Op_amp_integrator&amp;diff=27059</id>
		<title>Op amp integrator</title>
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		<updated>2013-12-14T14:57:25Z</updated>

		<summary type="html">&lt;p&gt;91.180.188.40: &lt;/p&gt;
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&lt;div&gt;{{Underlinked|date=January 2013}}&lt;br /&gt;
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&#039;&#039;&#039;Suspension&#039;&#039;&#039; is a construction passing from a map to a flow. Namely, let &amp;lt;math&amp;gt;X&amp;lt;/math&amp;gt; be a metric space, &amp;lt;math&amp;gt;f:X\to X&amp;lt;/math&amp;gt; be a continuous map and &amp;lt;math&amp;gt;r:X\to\mathbb{R}^+&amp;lt;/math&amp;gt; be a function (roof function or ceiling function) bounded away from 0. Consider the quotient space &lt;br /&gt;
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:&amp;lt;math&amp;gt;X_r=\{(x,t):0\le t\le r(x),x\in X\}/(x,r(x))\sim(fx,0). &amp;lt;/math&amp;gt;&lt;br /&gt;
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The suspension of &amp;lt;math&amp;gt;(X,f)&amp;lt;/math&amp;gt; with roof function &amp;lt;math&amp;gt;r&amp;lt;/math&amp;gt; is the semiflow&amp;lt;ref&amp;gt;M. Brin and G. Stuck, &#039;&#039;Introduction to Dynamical Systems&#039;&#039;, Cambridge University Press, 2002.&amp;lt;/ref&amp;gt; &amp;lt;math&amp;gt;f_t:X_r\to X_r&amp;lt;/math&amp;gt; induced by the time-translation &amp;lt;math&amp;gt;T_t:X\times\mathbb{R}\to X\times\mathbb{R}, (x,s)\mapsto (x,s+t)&amp;lt;/math&amp;gt;.&lt;br /&gt;
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If &amp;lt;math&amp;gt;r(x)\equiv 1&amp;lt;/math&amp;gt;, then the quotient space is also called the [[mapping torus]] of &amp;lt;math&amp;gt;(X,f)&amp;lt;/math&amp;gt;.&lt;br /&gt;
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==References==&lt;br /&gt;
&amp;lt;!--- See http://en.wikipedia.org/wiki/Wikipedia:Footnotes on how to create references using &amp;lt;ref&amp;gt;&amp;lt;/ref&amp;gt; tags which will then appear here automatically --&amp;gt;&lt;br /&gt;
{{Reflist}}&lt;br /&gt;
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&amp;lt;!--- Categories ---&amp;gt;&lt;br /&gt;
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[[Category:Dynamical systems]]&lt;/div&gt;</summary>
		<author><name>91.180.188.40</name></author>
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