Volterra series expansions represent an important model for the representation, analysis and synthesis of nonlinear dynamical systems. However, a significant problem with this approach to system identification is that the number of terms required to be estimated grows exponentially with the order of the expansion. In practice, therefore, the Volterra series is typically truncated to consist of,...

This paper presents a study aiming to define a nonlinear model, based on the Volterra series, of the high density optical disc read out process. I!nder high density condition, because of the high linear density and reduced track pitch, the signal read out is not a linear process and suffers from cross talk. To cope with such a problem the identification of a suitable nonlinear model is required...

Subharmonic images are becoming interestingly in medical ultrasound, as the improvement of contrastto-tissue ratio (CTR). However, an important part for image enhancement is processing techniques. In this study, frequency response functions (FRFs) of multiple-input-multiple-output (MIMO) Volterra systems were used to investigate potentially possible in separating subharmonic frequency for the q...

In this paper, we focus on model reduction of large-scale bilinear systems. The main contributions are threefold. First, we introduce a new framework for interpolatory model reduction of bilinear systems. In contrast to the existing methods where interpolation is forced on some of the leading subsystem transfer functions, the new framework shows how to enforce multipoint interpolation of the un...

This paper examines the process and final result of extending the basic Lotka-Volterra predator-prey model to include different age groups within each population. Basic analysis of the results were performed to determine the relevance of the proposed extension. Calculations and graphing were handled with MatLab. The natural outcome of the model should be either a periodic cycle about an equilib...

This paper considers a Lotka-Volterra model with time delays and delay dependent parameters. The linear stability conditions are obtained with characteristic root method. The Hopf bifurcation is demonstrated. Using normal form theory and center manifold theory, Some explicit formulae for determining the stability and the direction of the Hopf bifurcation periodic solutions are derived. Finally,...

In the paper stochastic Volterra equations of nonscalar type in Hilbert space are studied. The aim of the paper is to provide some results on stochastic convolution and mild solutions to those Volterra equations. The motivation of the paper comes from a model of aging viscoelastic materials. The pseudo-resolvent approach is used.

This work considers behavior modeling of analog to digital converters with applications in the radio frequency range, including the field of telecommunication as well as test and measurement instrumentation, where the conversion from analog to digital signals often is a bottleneck in performance. The models are intended to postprocess output data from the converter and thereby improve the perfo...

Starting from the Volterra approach and assuming fading memory, a very efficient method to identify weakly non-linear systems is presented. Making special assumptions on the Volterra kernels, one ends up in the Hammerstein model, which has less complexity than the Volterra model, thus reducing the numerical effort. Using FIR filters to realize the Hammerstein model, no starting values are neces...

Nonlinearity in evoked hemodynamic responses often presents in event-related fMRI studies. Volterra series, a higher-order extension of linear convolution, has been used in the literature to construct a nonlinear characterization of hemodynamic responses. Estimation of the Volterra kernel coefficients in these models is usually challenging due to the large number of parameters. We propose a new...