Informatica

T wave features suitable for automatic T wave alternans detection in low signal-to-noise ratio electrocardiograms are explored using a correlation-to-template-based algorithm for detecting T waves of variable duration. Amplitude and area features of T waves are found to be notably less sensitive to template selection than are duration features. T wave alternans features and measures which can be determined more stably provide better classification accuracy of patients with and without coronary artery lesions.

Traditional population dynamics models, explaining separate aspects of observed ecological phenomena, are well understood mathematically, but their extension to a wider class of phenomena is difficult. Artificial life models represent another extreme, capable of simulating almost every biological phenomenon, but not accessible to mathematical analysis. A population model having a scope between the two extremes – but flexible, extensible, and within reach of mathematical analysis – is introduced in this paper. The model is based on piece-wise linear dynamical models of individual organisms. Parameter ranges in which the model meets natural ecological requirements is explored through analysis and simulations.