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Noise in an insect outbreak model

Bao-Quan Ai·Wei Chen·Xian-Ju Wang·Guo-Tao Liu·De-Hua Wen·Hui-Zhang Xie·Liang-Gang Liu
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Abstract

We study the steady state properties of an insect (spruce budworm) outbreak model in the presence of Gaussian white noise. Based on the corresponding Fokker-Planck equation the steady state solution of the probability distribution function and its extrema have been investigated. It was found that fluctuations of the insect birth rate reduces the population of the insects while fluctuations of predation rate and the noise correlation can prevent the population of the insects from going into extinction. Noise in the model can induce a phase transition.

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Bao-Quan Ai, Wei Chen, Xian-Ju Wang, Guo-Tao Liu, De-Hua Wen, Hui-Zhang Xie, Liang-Gang Liu. 2003-06-25. Noise in an insect outbreak model. https://arxiv.org/abs/physics/0306177

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