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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Optimal noise in a stochastic model for local search

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Autor(es):
Noetel, J. [1] ; Freitas, V. L. S. [2] ; Macau, E. E. N. [2, 3] ; Schimansky-Geier, L. [1, 4]
Número total de Autores: 4
Afiliação do(s) autor(es):
[1] Humboldt Univ, Inst Phys, Newtonstr 15, D-12489 Berlin - Germany
[2] Natl Inst Space Res, BR-12227010 Sao Jose Dos Campos, SP - Brazil
[3] Univ Fed Sao Paulo, BR-12247014 Sao Jose Dos Campos, SP - Brazil
[4] Humboldt Univ, Berlin Bernstein Ctr Computat Neurosci, Unter Linden 6, D-10099 Berlin - Germany
Número total de Afiliações: 4
Tipo de documento: Artigo Científico
Fonte: Physical Review E; v. 98, n. 2 AUG 27 2018.
Citações Web of Science: 2
Resumo

We develop a prototypical stochastic model for a local search around a given home. The stochastic dynamic model is motivated by experimental findings of the motion of a fruit fly around a given spot of food but will generally describe the local search behavior. The local search consists of a sequence of two epochs. In the first the searcher explores new space around the home, whereas it returns to the home during the second epoch. In the proposed two-dimensional model both tasks are described by the same stochastic dynamics. The searcher moves with constant speed and its angular dynamics is driven by a symmetric alpha-stable noise source. The latter stands for the uncertainty to decide the new direction of motion. The main ingredient of the model is the nonlinear interaction dynamics of the searcher with its home. In order to determine the new heading direction, the searcher has to know the actual angles of its position to the home and of the heading vector. A bound state to the home is realized by a permanent switch of a repulsive and attractive forcing of the heading direction from the position direction corresponding to search and return epochs. Our investigation elucidates the analytic tractability of the deterministic and stochastic dynamics. Noise transforms the conservative deterministic dynamics into a dissipative one of the moments. The noise enables a faster finding of a target distinct from the home with optimal intensity. This optimal situation is related to the noise-dependent relaxation time. It is uniquely defined for all alpha and distinguishes between the stochastic dynamics before and after its value. For times large compared to this, we derive the corresponding Smoluchowski equation and find diffusive spreading of the searcher in the space. We report on the qualitative agreement with the experimentally observed spatial distribution, noisy oscillatory return times, and spatial autocorrelation function of the fruit fly. However, as a result of its simplicity, the model aims to reproduce the local search behavior of other units during their exploration of surrounding space and their quasiperiodic return to a home. (AU)

Processo FAPESP: 17/04552-9 - Sincronização e controle de rede de osciladores caóticos e aplicações ao controle de veículos autônomos móveis em deslocamento de formação
Beneficiário:Vander Luis de Souza Freitas
Linha de fomento: Bolsas no Brasil - Doutorado
Processo FAPESP: 15/50122-0 - Fenômenos dinâmicos em redes complexas: fundamentos e aplicações
Beneficiário:Elbert Einstein Nehrer Macau
Linha de fomento: Auxílio à Pesquisa - Temático