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DTSTAMP:20260519T094249Z
SUMMARY:Imperial-UCL Numerics Seminar – NA Seminar: Alex Baspalov (Birmin
 gham)
DESCRIPTION:A posteriori error estimation and adaptivity for stochastic col
 location FEM\nThis talk concerns the design and analysis of an adaptive FE
 M-based solution strategy for PDE problems with uncertain or parameter-dep
 endent inputs. High-fidelity numerical solutions to these problems are inf
 easible to compute in many realistic applications. Conversely\, so-called 
 surrogate approximations that are functions of the (stochastic) parameters
  are not only effective in approximating the input-output map but can also
  be used to estimate a wide range of quantities of interest—specific (an
 d usually localised) features of the solution to a PDE. The talk will addr
 ess: (i) the reliable control of errors in computing solutions to parametr
 ic PDEs (or the associated quantities of interest) using surrogate approxi
 mations\, and (ii) systematic approaches to reduce those errors via adapti
 ve algorithms.\nWe will focus on one particular type of surrogate approxim
 ations—sparse grid stochastic collocation finite element approximations 
 that combine sparse grid interpolation in the parameter domain with finite
  element discretisation in the physical (spatial) domain. We propose a nov
 el approach to a posteriori error estimation in this approximation setting
 . This employs hierarchical error estimates that are useful for reliable e
 rror control and also provide practical error indicators for guiding the a
 daptive refinement process. We will demonstrate the effectivity and robust
 ness of the proposed error estimation strategy. We will then discuss the p
 erformance of the developed adaptive algorithms. The latter include goal-o
 riented adaptive algorithms for approximating quantities of interest repre
 sented by linear or nonlinear goal functionals.\n
URL:https://www.imperial.ac.uk/events/185195/imperial-ucl-numerics-seminar-
 na-seminar-alex-baspalov-birmingham/
DTSTART;TZID=Europe/London:20250129T150000
DTEND;TZID=Europe/London:20250129T160000
LOCATION:140\, Huxley Building\, South Kensington Campus\, Imperial College
  London\, London\, SW7 2AZ\, United Kingdom
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