Sökning: "weak factorization"

Hittade 2 avhandlingar innehållade orden weak factorization.

1. 1. Fragmentation cross sections: measurement, systematics and model developement

   Författare :Chiara La Tessa; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; projectile total charge-changing cross sections; weak factorization; strong factorization; projectile partial charge-changing cross sections; heavy-ions; space radioprotection; nuclear fragmentation;

   Sammanfattning : Man's attitude towards space exploration has been mainly limited by the health risk related to the exposure to the space radiation environment. Some components of the space field can be characterized by such a high flux to kill a man if directly exposed and in general, all space radiation constitutes a hazard for astronauts engaged in long-term missions. LÄS MER

3. 2. Efficient Density Matrix Methods for Large Scale Electronic Structure Calculations

   Författare :Anastasia Kruchinina; Emanuel H. Rubensson; Elias Rudberg; David Bowler; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; electronic structure; linear scaling; density matrix; density functional theory; Hartree-Fock; recursive polynomial expansion; density matrix purification; eigenvectors; molecular orbitals; stopping criteria; inverse factorization; matrix sparsity; parallelization; Scientific Computing; Beräkningsvetenskap;

   Sammanfattning : Efficient and accurate methods for computing the density matrix are necessary to be able to perform large scale electronic structure calculations. For sufficiently sparse matrices, the computational cost of recursive polynomial expansions to construct the density matrix scales linearly with increasing system size. LÄS MER