Local to global normalization dynamic by nonlinear local interactions

PHYSICA D-NONLINEAR PHENOMENA

卷:237

Article

Keil, Matthias S.

关键词: adaptation;    normalization;    diffusion;    network;   

DOI  :  10.1016/j.physd.2007.10.011

来源: Elsevier

【 摘 要 】

Here, I present a novel method for normalizing a finite set of numbers, which is studied by the domain of biological vision. Normalizing in this context means searching the maximum and minimum number in a set and then rescaling all numbers such that they fit into a numerical interval. My method computes the minimum and maximum number by two pseudo-diffusion processes in separate diffusion layers. Activity of these layers feed into a third layer for performing the rescaling operation. The dynamic of the network is richer than merely performing a rescaling of its input, and reveals phenomena like contrast detection, contrast enhancement and a transient compression of the numerical range of the input. Apart from presenting computer simulations, some properties of the diffusion operators and the network are analysed mathematically. Furthermore, a method is proposed for to freeze the model's state when adaptation is observed. (C) 2007 Elsevier B.V. All rights reserved.

【 授权许可】

Free