In this paper for all $p>1$ we prove that the pull-in voltage of the $p$-MEMS (micro-electro mechanical systems) problems on a smooth bounded domain of $\mathbb R^{d}, d\geq1,$ is minimized by symmetrizing the domain and the permittivity profile. The proofs rely on some suitable version of Talenti's comparison principle. We also demonstrate our method to the multidimensional MEMS type problems on the whole space $\mathbb R^{d}, d\geq3,$ and the Dirichlet boundary value problems of second order uniformly elliptic differential operators.
The abstract quasilinear Cauchy problem for a MEMS model with two free boundaries
在本文中,我们重新制定了一个理想的静电驱动的MEMS器件的动力学与两个弹性膜作为一个抽象的准线性发展方程的初值问题的数学模型。应用压缩映射定理,它表明,该模型是局部适定的时间为任何值的设备的源电压。此外,它被证明,这里考虑的MEMS模型具有全局解的小电源电压,而大电源电压的模型的解决方案有一个有限的最大存在时间。此外,我们评论的关系,我们的模型,它的固定版本和它的小纵横比限制,存在一个独特的指数稳定的稳定状态,并证明收敛到一个解决方案的窄间隙模型消失的纵横比限制。我们的结果扩展了[Martin Kohlmann:On an elliptic-parabolic MEMS model with two自由边界,2014]中提出的椭圆抛物MEMS模型的讨论,导致半线性抽象发展方程的柯西问题。
Existence and nonexistence of solutions for fractional elliptic equations arising from closed MEMS model
Fudan University(复旦大学);Shanghai Institute for Mathematics and Interdisciplinary Sciences (SIMIS)(上海数学与交叉学科研究院);Jiangxi Normal University(江西师范大学);Jiangsu University(江苏大学)
Existence and dynamic properties of a parabolic nonlocal MEMS equation
设$Ω\subset\mathbb{R}^n$为$C^2$有界域,$χ>0$为常数.我们将证明非局部MEMS方程$-Δv=\lam/(1-v)^2(1+χ\int_Ω1/(1-v)dx)^2$ in $Ω$,$v=0$ on $\1Ω$的常数$λ_N\geλ_N^{\ast}\geλ^{\ast}(1+χ\int_Ω\frac{dx}{1-w_{\ast}})^2$的存在性,使得对于任何$0\leλ<λ_N^{\ast}$都存在解,对于任何$λ>λ_N$都不存在解,其中$λ^{\ast}$是吸合电压,$w_{\ast}$是$Ω$中$-Δv=\lam/(1-v)^2$的最小解的极限,$v=0$ on $\1Ω$为$λ\nearrow λ^{\ast}$。我们将证明在$λ$上的各种有界性条件下,相应的抛物型非局部MEMS方程的整体解的存在性,唯一性和渐近行为。当$λ$较大时,我们还得到了抛物型非局部MEMS方程解的猝灭行为。