Stability and Bogdanov-Takens Bifurcation of an SIS Epidemic Model with Saturated Treatment Function

<div>The unique endemic equilibrium <svg height="10.5763pt" id="M273" style="vertical-align:-0.04990005pt" version="1.1" viewbox="-0.0498162 -10.5264 14.791 10.5763" width="14.791pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.0135,0,0,-0.0135,0,0)"><path d="M593 650H142L136 622C219 616 224 611 209 531L130 120C114 39 108 34 23 28L17 0H501C518 32 557 130 568 158L540 169C519 132 495 93 469 70C439 43 409 35 332 35C272 35 241 37 225 50C211 61 211 89 222 149L253 320H350C441 320 443 312 441 239H471L510 434H481C455 366 448 358 360 358H260L303 572C311 613 312 615 348 615H431C509 615 522 603 532 581C544 555 546 531 545 491L574 493C583 555 592 631 593 650Z" id="g113-70"></path><glyph.data ascent="3473" descent="-2876" horiz-adv-x="616" vert-adv-y="616"></glyph.data></g><g transform="matrix(.0095,0,0,-0.0095,8.346,-5.984)"><path d="M486 158C486 177 478 202 466 220C413 228 386 236 336 262C386 288 413 297 466 304C478 323 486 347 485 366C470 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Mathematical Problems in Engineering

fig5

Figure 5

Figure 5: Stability and Bogdanov-Takens Bifurcation of an SIS Epidemic Model with Saturated Treatment Function 