English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

Robust mixed finite element methods are developed for a quad-curl singularperturbation problem. Lower order H(grad curl)-nonconforming butH(curl)-conforming finite elements are constructed, which are extended tononconforming finite element Stokes complexes and the associated commutativediagrams. Then H(grad curl)-nonconforming finite elements are employed todiscretize the quad-curl singular perturbation problem, which possess the sharpand uniform error estimates with respect to the perturbation parameter. TheNitsche's technique is exploited to achieve the optimal convergence rate in thecase of the boundary layers. Numerical results are provided to verify thetheoretical convergence rates. In addition, the regularity of the quad-curlsingular perturbation problem is established.

Robust mixed finite element methods for a quad-curl singular perturbation problem