direct solver

 The main purpose of this work is to present a new parallel direct solver: Dissection solver. It is based on LU
factorization of the sparse matrix of the linear system and allows to
detect automatically and handle properly the zero-energy modes, which
are important when dealing with DDM. A performance evaluation and
comparisons with other direct solvers (MUMPS, DSCPACK) are also given
for both sequential and parallel computations. Results of numerical
experiments with a two-level parallelization of large-scale structural
analysis problems are also presented: FETI is used for the global
problem parallelization and Dissection for the local