Modelling the Periodic Outbreak of Measles in Mainland China

<div>(a) The number of infected individuals with symptoms under the two situations: no control is used and three types of controls are implemented simultaneously; (b)–(d) The time series of corresponding optimal control functions <span class="nowrap"><svg height="14.0461pt" id="M148" style="vertical-align:-3.9436pt" version="1.1" viewbox="-0.0498162 -10.1025 90.144 14.0461" width="90.144pt" 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="M515 96L502 119C471 88 431 62 423 62C416 62 411 70 417 101C440 223 469 341 497 448H486L412 422L380 277C330 188 210 57 152 57C137 57 126 69 139 124L195 366C210 431 205 448 182 448C155 448 89 413 23 350L36 326C73 354 103 376 112 376C118 376 118 365 113 340L61 118C54 90 52 68 52 51C52 0 75 -12 98 -12S151 -3 181 17C242 58 305 119 362 193H364L345 104C323 3 339 -12 359 -12C390 -12 464 35 515 96Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,6.994,-5.741)"><path d="M486 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Mathematical Problems in Engineering

Modelling the Periodic Outbreak of Measles in Mainland China

Figure 6