Analysis of a Diffusive Heroin Epidemic Model in a Heterogeneous Environment

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(a) <span class="nowrap"><svg height="11.927pt" id="M327" style="vertical-align:-3.291101pt" version="1.1" viewbox="-0.0498162 -8.6359 36.0715 11.927" width="36.0715pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M378 16V19L193 101V573L189 575L64 511V497C112 490 117 487 117 401V85C117 65 122 58 143 49L273 -9C281 -13 290 -15 300 -15C311 -15 322 -12 331 -8L378 16ZM701 30L693 44C684 39 674 35 663 35C642 35 625 36 617 48L441 312V315C512 355 581 413 581 494C581 549 543 595 492 617L420 650C405 657 391 665 375 665C349 665 329 647 306 635L235 599V127H239C273 140 282 148 282 167V586L335 613L425 573C470 552 505 511 505 462C505 397 447 353 387 322C375 316 363 308 363 295C363 279 375 261 386 245L541 13C552 -4 572 -15 595 -15C606 -15 617 -12 626 -8L701 30Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,9.802,3.132)"><path d="M245 635C92 635 37 457 37 312C37 149 91 -12 244 -12C395 -12 449 166 449 312C449 469 395 635 245 635ZM243 598C332 598 358 454 358 312C358 173 334 26 245 26C158 26 128 174 128 313S152 598 243 598Z"></path></g><g transform="matrix(.013,0,0,-0.013,18.38,0)"><path d="M512 230V281L75 514V456L453 256V254L75 55V-3L512 230Z"></path></g><g transform="matrix(.013,0,0,-0.013,29.643,0)"><path d="M384 0V27C293 34 287 42 287 114V635C232 613 172 594 109 583V559L157 557C201 555 205 550 205 499V114C205 42 199 34 109 27V0H384Z"></path></g></svg>;</span> (b) <span class="nowrap"><svg height="11.927pt" id="M328" style="vertical-align:-3.291101pt" version="1.1" viewbox="-0.0498162 -8.6359 36.0715 11.927" width="36.0715pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M378 16V19L193 101V573L189 575L64 511V497C112 490 117 487 117 401V85C117 65 122 58 143 49L273 -9C281 -13 290 -15 300 -15C311 -15 322 -12 331 -8L378 16ZM701 30L693 44C684 39 674 35 663 35C642 35 625 36 617 48L441 312V315C512 355 581 413 581 494C581 549 543 595 492 617L420 650C405 657 391 665 375 665C349 665 329 647 306 635L235 599V127H239C273 140 282 148 282 167V586L335 613L425 573C470 552 505 511 505 462C505 397 447 353 387 322C375 316 363 308 363 295C363 279 375 261 386 245L541 13C552 -4 572 -15 595 -15C606 -15 617 -12 626 -8L701 30Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,9.802,3.132)"><path d="M245 635C92 635 37 457 37 312C37 149 91 -12 244 -12C395 -12 449 166 449 312C449 469 395 635 245 635ZM243 598C332 598 358 454 358 312C358 173 334 26 245 26C158 26 128 174 128 313S152 598 243 598Z"></path></g><g transform="matrix(.013,0,0,-0.013,18.38,0)"><path d="M512 -3V55L134 254V256L512 456V514L75 281V230L512 -3Z"></path></g><g transform="matrix(.013,0,0,-0.013,29.643,0)"><path d="M384 0V27C293 34 287 42 287 114V635C232 613 172 594 109 583V559L157 557C201 555 205 550 205 499V114C205 42 199 34 109 27V0H384Z"></path></g></svg>.</span></div>

Complexity

fig3

Figure 3

Figure 3: Analysis of a Diffusive Heroin Epidemic Model in a Heterogeneous Environment 