Dynamic Modeling and Analysis of  the Email Virus Propagation

<table>The phase diagram of system (<a href="https://static.hindawi.com/articles/ddns/volume-2012/472072/figures/#EEq2.5">2.9</a>) when <svg height="20.4125" id="M328" style="vertical-align:-2.64594pt" version="1.1" viewbox="0 0 147.5 20.4125" width="147.5" xmlns="http://www.w3.org/2000/svg">
<g transform="matrix(1.25,0,0,-1.25,0,20.4125)">
<g transform="translate(72,-55.67)">
<text transform="matrix(1,0,0,-1,-71.95,58.36)">
<tspan style="font-size: 12.50px; " x="30.459999" y="-0.60000002">√</tspan>
<tspan style="font-size: 12.50px; " x="0" y="0">𝐵</tspan>
<tspan style="font-size: 12.50px; " x="12.165419" y="0">&gt;</tspan>
<tspan style="font-size: 12.50px; " x="24.205809" y="0">2</tspan>
</text>
<g>
<path d="m -29.88,70.71 18.56,0" style="fill:none;stroke:#000000;stroke-width:0.82499999;stroke-linecap:butt;stroke-linejoin:miter;stroke-miterlimit:10;stroke-opacity:1;stroke-dasharray:none"></path>
</g>
<text transform="matrix(1,0,0,-1,-29.88,58.36)">
<tspan style="font-size: 12.50px; " x="0" y="0">𝑛</tspan>
<tspan style="font-size: 12.50px; " x="6.2139912" y="0">/</tspan>
<tspan style="font-size: 12.50px; " x="9.6898251" y="0">𝑚</tspan>
<tspan style="font-size: 12.50px; " x="21.342621" y="0">+</tspan>
<tspan style="font-size: 12.50px; " x="32.682842" y="0">1</tspan>
<tspan style="font-size: 12.50px; " x="38.934341" y="0">/</tspan>
<tspan style="font-size: 12.50px; " x="42.410175" y="0">𝑚</tspan>
<tspan style="font-size: 12.50px; " x="54.062973" y="0">+</tspan>
<tspan style="font-size: 12.50px; " x="65.403191" y="0">1</tspan>
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</svg>(bistability).</table>

Discrete Dynamics in Nature and Society

Dynamic Modeling and Analysis of the Email Virus Propagation

Figure 4