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On the singular limit of a boundary delayed Kuramoto-Sivashinsky-Korteweg-de Vries equation: Well-posedness and stability results

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This article is concerned with a Kuramoto–Sivashinsky-Korteweg-de Vries equation in a bounded interval. The equation as well as one of the boundary conditions are supposed to be the subject of the presence of a parameter ν0\nu\to 0. Moreover, this specific boundary condition has a time-delay effect. As ν\nu tends to zero, we show that one can obtain the findings of [4,58] concerning two Korteweg–de Vries equations. Indeed, we are able to retrieve the well-posedness and stability results for the Korteweg–de Vries problem without delay [58] and with delay [4] under the same conditions, as a singular limit of the Kuramoto–Sivashinsky equation with delay. The proof is based in the well-known Galerkin method together with the multiplier technique.

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... However, when delays become time-varying, the complexity of analyzing system stability significantly rises. Numerous studies have delved into the stability analysis of partial differential equations (PDEs) with time-delay or time-varying delays, with notable references, such as [12,15,16,26,30,37]. ...
... Thanks to (12), the choice of ξ is feasible. ...
... Proposition 3.3. Let (u 0 , z 0 (·, −θ(0)·)) ∈ H and assume that the nonnegative functions a and b belonging to L ∞ (0, L) satisfy (11) and (12). We also suppose that (8), (9) and (10) holds and f ∈ L 1 (0, T, L 2 (0, L)). ...
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