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No Switching Policy is Optimal for a Positive Linear System with a Bottleneck Entrance

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 نشر من قبل M. Ali Al-Radhawi
 تاريخ النشر 2019
  مجال البحث
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We consider a nonlinear SISO system that is a cascade of a scalar bottleneck entrance and an arbitrary Hurwitz positive linear system. This system entrains i.e. in response to a $T$-periodic inflow every solution converges to a unique $T$-periodic solution of the system. We study the problem of maximizing the averaged throughput via controlled switching. The objective is to choose a periodic inflow rate with a given mean value that maximizes the averaged outflow rate of the system. We compare two strategies: 1) switching between a high and low value, and 2) using a constant inflow equal to the prescribed mean value. We show that no switching policy can outperform a constant inflow rate, though it can approach it asymptotically. We describe several potential applications of this problem in traffic systems, ribosome flow models, and scheduling at security checks.



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