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arXiv · 1612.04681

Stochastic level-set method for shape optimisation

Abstract

We present a new method for stochastic shape optimisation of engineering structures. The method generalises an existing deterministic scheme, in which the structure is represented and evolved by a level-set method coupled with mathematical programming. The stochastic element of the algorithm is built on the methods of statistical mechanics and is designed so that the system explores a Boltzmann-Gibbs distribution of structures. In non-convex optimisation problems, the deterministic algorithm can get trapped in local optima: the stochastic generalisation enables sampling of multiple local optima, which aids the search for the globally-optimal structure. The method is demonstrated for several simple geometrical problems, and a proof-of-principle calculation is shown for a simple engineering structure.

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BibTeXRIS

Lester O. Hedges, H. Alicia Kim, Robert L. Jack. 2016-12-14. Stochastic level-set method for shape optimisation. https://doi.org/10.1016/j.jcp.2017.07.010

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