Firing map of an almost periodic input function
  In mathematical biology and the theory of electric networks the firing map of an integrate-and-fire system is a notion of importance. In order to prove useful properties of this map authors of previous papers assumed that the stimulus function f of the system \dot{x}= f(t,x) is continuous and usually periodic in the time variable. In this work we show that the required properties of the firing map for the simplified model \dot{x}=f(t) still hold if f \in L_{loc}^1(R) and f is an almost periodic function. Moreover, in this way we prepare a formal framework for next study of a discrete dynamics of the firing map arising from almost periodic stimulus that gives information on consecutive resets (spikes). 
W. Marzantowicz (1), J. Signerska (2) ((1) Faculty of Mathematics and   Computer Sci., Adam Mickiewicz University of Poznan,...
math.DS