Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A New Refinement-Free Preconditioner for the Symmetric Formulation in
  Electroencephalography   Widely employed for the accurate solution of the electroencephalography
forward problem, the symmetric formulation gives rise to a first kind,
ill-conditioned operator ill-suited for complex modelling scenarios. This work
presents a novel preconditioning strategy based on an accurate spectral
analysis of the operators involved which, differently from other
Calder\'on-based approaches, does not necessitate the barycentric refinement of
the primal mesh (i.e., no dual matrix is required). The discretization of the
new formulation gives rise to a well-conditioned, symmetric, positive-definite
system matrix, which can be efficiently solved via fast iterative techniques.
Numerical results for both canonical and realistic head models validate the
effectiveness of the proposed formulation.

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The categories of this paper are: cond-mat
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The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
15
The categories of this paper are: nucl-ex
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The categories of this paper are: supr-con
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The categories of this paper are: hep-ex
26
The categories of this paper are: bayes-an
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The categories of this paper are: econ
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The categories of this paper are: q-fin
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The categories of this paper are: comp-gas
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The categories of this paper are: acc-phys
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The categories of this paper are: alg-geom
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The categories of this paper are: adap-org
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The categories of this paper are: astro-ph
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The categories of this paper are: eess
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The categories of this paper are: quant-ph