Intrinsic Ultracontractivity for Domains in Negatively Curved Manifolds

Autor: Michiel van den Berg, Hiroaki Aikawa, Jun Masamune

Publikováno v: Aikawa, H, van den Berg, M & Masamune, J 2021, ' Intrinsic Ultracontractivity for Domains in Negatively Curved Manifold ', Computational Methods and Function Theory, vol. 21, pp. 797–824 . https://doi.org/10.1007/s40315-021-00402-8

Let $M$ be a complete, non-compact, connected Riemannian manifold with Ricci curvature bounded from below by a negative constant. A sufficient condition is obtained for open and connected sets $D$ in $M$ for which the corresponding Dirichlet heat sem

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b9f124e53360b3675f7fc1b8c914624e
https://doi.org/10.1007/s40315-021-00402-8

On a Pólya functional for rhombi, isosceles triangles, and thinning convex sets

Autor: Carlo Nitsch, Michiel van den Berg, Cristina Trombetti, Vincenzo Ferone

Publikováno v: van den Berg, M, Ferone, V, Nitsch, C & Trombetti, C 2020, ' On a Pólya functional for rhombi, isosceles triangles, and thinning convex sets ', Revista Matemática Iberoamericana, vol. 36, no. 7, pp. 2091-2105 . https://doi.org/10.4171/rmi/1192

Let Ω be an open convex set in Rm with finite width, and with boundary ∂Ω. Let vΩ be the torsion function for Ω, i.e., the solution of −Δv=1,v|∂Ω=0. An upper bound is obtained for the product of ∥vΩ∥L∞(Ω)λ(Ω), where λ(Ω) is th

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::4eb82a1eacbac341be141cea39d29a92
https://doi.org/10.4171/rmi/1192

The diagnostic value of duplex ultrasound in detecting the presence and location of a stenosis in an autologous arteriovenous fistula

Autor: Michiel van den Berg, R.J. Hissink, Frank Gh van der Kleij, Admira Ćosović, Marion C Hoekstra, Petra M.C. Callenbach

Publikováno v: The Journal of Vascular Access. 21:217-222

Objective: To determine the value of duplex ultrasound in the detection of significant (⩾50%) stenosis and the location of the stenosis in arteriovenous fistula, compared to angiography. Methods: Patients who underwent construction of an autologous

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::40bc80ccc900d0e41fc2b4778765d1a3
https://doi.org/10.1177/1129729819869998

Sign changing solutions of Poisson's equation

Autor: Dorin Bucur, Michiel van den Berg

Publikováno v: van den Berg, M & Bucur, D 2020, ' Sign changing solutions of Poisson's equation ', Proceedings of the London Mathematical Society, vol. 121, no. 3, pp. 513-536 . https://doi.org/10.1112/plms.12334

Let $\Omega$ be an open, possibly unbounded, set in Euclidean space $\R^m$ with boundary $\partial\Omega,$ let $A$ be a measurable subset of $\Omega$ with measure $|A|$, and let $\gamma \in (0,1)$. We investigate whether the solution $v_{\Om,A,\gamma

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::a702b94b3698ef7c1178877167b2f206
https://research-information.bris.ac.uk/en/publications/54aa7908-499b-4bb3-b68e-5199dadb5cb4

Heat flow from polygons

Autor: Katie Gittins, Peter B. Gilkey, Michiel van den Berg

Publikováno v: Potential Analysis
van den Berg, M, Gilkey, P & Gittins, K 2019, ' Heat flow from polygons ', Potential Analysis . https://doi.org/10.1007/s11118-019-09797-5

We study the heat flow from an open, bounded set $D$ in $\R^2$ with a polygonal boundary $\partial D$. The initial condition is the indicator function of $D$. A Dirichlet $0$ boundary condition has been imposed on some but not all of the edges of $\p

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::45262ea4e9dc7498be81af0542769772
http://arxiv.org/abs/1902.02606