Publications by authors named "Manuel R Alfonso"

Arterial pressure waves have been described in one dimension using several approaches, such as lumped (Windkessel) or distributed (using Navier-Stokes equations) models. An alternative approach consists of modeling blood pressure waves using a Korteweg-de Vries (KdV) equation and representing pressure waves as combinations of solitons. This model captures many key features of wave propagation in the systemic network and, in particular, pulse pressure amplification (PPA), which is a mechanical biomarker of cardiovascular risk.

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This paper presents the development of a fusion strategy to integrate and calibrate signals from magnetometers, gyroscopes and accelerometers to implement a magnetic, angular rate and gravity (MARG) sensor system. The aim of such algorithms is to capture signals from the individual sensors and identify, compensate and reduce external and internal errors such as bias, scale factor and drifts, which highly depend on the noise levels. The necessary calibrations to ensure the reliability of captured data are also presented.

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Models define a simplification of reality, which help to understand function. The arterial system has been modeled in many ways: lumped models, tube models and anatomically based distributed models. In this work, arterial segments were modeled as thin nonlinear elastic tubes filled with an incompressible fluid, whose governing dynamics were denoted by the Korteweg and DeVries equation.

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