An evolutionary algorithm for the surface structure problem


Autoria(s): Martinez Mateo, Jesus; López Fagúndez, Mª Francisca; Martín Gago, José Angel; Martín Ayuso, Vicente
Data(s)

2009

Resumo

Many macroscopic properties: hardness, corrosion, catalytic activity, etc. are directly related to the surface structure, that is, to the position and chemical identity of the outermost atoms of the material. Current experimental techniques for its determination produce a “signature” from which the structure must be inferred by solving an inverse problem: a solution is proposed, its corresponding signature computed and then compared to the experiment. This is a challenging optimization problem where the search space and the number of local minima grows exponentially with the number of atoms, hence its solution cannot be achieved for arbitrarily large structures. Nowadays, it is solved by using a mixture of human knowledge and local search techniques: an expert proposes a solution that is refined using a local minimizer. If the outcome does not fit the experiment, a new solution must be proposed again. Solving a small surface can take from days to weeks of this trial and error method. Here we describe our ongoing work in its solution. We use an hybrid algorithm that mixes evolutionary techniques with trusted region methods and reuses knowledge gained during the execution to avoid repeated search of structures. Its parallelization produces good results even when not requiring the gathering of the full population, hence it can be used in loosely coupled environments such as grids. With this algorithm, the solution of test cases that previously took weeks of expert time can be automatically solved in a day or two of uniprocessor time.

Formato

application/pdf

Identificador

http://oa.upm.es/19131/

Idioma(s)

eng

Publicador

Facultad de Informática (UPM)

Relação

http://oa.upm.es/19131/1/INVE_MEM_2009_91509.pdf

http://link.springer.com/chapter/10.1007%2F978-3-642-02481-8_40

info:eu-repo/semantics/altIdentifier/doi/null

Direitos

http://creativecommons.org/licenses/by-nc-nd/3.0/es/

info:eu-repo/semantics/openAccess

Fonte

Distributed computing, artificial intelligence, bioinformatics, soft computing, and ambient assisted living | 10th International Work-Conference on Artificial Neural Networks, IWANN 2009 Workshops | June 10-12, 2009 | Salamanca

Palavras-Chave #Física #Informática
Tipo

info:eu-repo/semantics/conferenceObject

Ponencia en Congreso o Jornada

PeerReviewed