Oscar Olarte

Vrije Universiteit Brussel | VUB · Department of Mechanical Engineering (MECH)

In modal identification, the value of the model parameters and the associated uncertainty depends on the quality of the measurements. The maximum likelihood estimator (mle) is a consistent and efficient estimator. This means that the value of the parameters trends asymptotically close to the true value, while the variance of such parameters is the...

The article presents a methodology to discriminate glucose levels using electrical impedance spectroscopy technology. The method is based on an adequate estimation and assessment of the impedance data followed by identification of a general rational fractional model. The methodology is illustrated on a group of saline–protein–glucose solutions at p...

The article presents a methodology to discriminate glucose levels using electrical impedance spectroscopy technology. The method is based on an adequate estimation and assessment of the impedance data followed by identification of a general rational fractional model. The methodology is illustrated on a group of saline–protein–glucose solutions at p...

Frequency domain modal parameter estimation from input–output data requires direct measurement or estimation of the input and output signals. In different applications those measurements, especially the excitation signals, are difficult to obtain and/or the assumptions could be poor or inappropriate (high uncertainty or high levels of noise). In th...

The paper addresses the development and performance-analysis of a lung function device for non-invasive forced oscillatory technique (FOT). The applied identification methodology allows estimating the level of noise and the level of non-linearities generated by the device and correct their influence on the patient's excitation signal. The repeatabi...

Electrochemical impedance spectroscopy (EIS) allows measuring the properties of the system as a function of the frequency as well as distinguishing between processes that could be involved: resistance, reactance, relaxation times, amplitudes, etc. Although it is possible to find related literature to in vitro and in vivo experiments to estimate glu...

For controlling, observing and optimizing engineering processes one needs often dedicated experiments. Unfortunately no measurement is exact such that deriving conclusions from a measurement campaign requires some caution. Hence, in order to control or optimize a certain parameter of interest, uncertainty of the parameter needs to be the measuremen...

In this paper an equivalent circuit model is employed in the characterization of the impedance measurements of saline solutions at physiological glucose concentrations. The impedance data are obtained using a three electrodes cell configuration since it allows measuring the potential accurately in the working electrode independently from the counte...

Electrical impedance spectroscopy (EIS) has been used to characterize different biological materials. This article exposes a methodology oriented to estimate glucose levels of a solution based on a rational fractional parametric model of the impedance data. The methodology is applied over saline–glucose solutions at five physiological glucose level...

In the last years attempts to develop a non-invasive glucose system based on the glucose levels in sweat have been studied. In this paper, 32 metal oxide semiconductor (MOS) sensors operating at different temperatures have been used to develop a multisensor olfactory system that allows to study the glucose levels in sweat. In order to develop repea...

Electrochemistry Impedance Spectroscopy has been proposed as a promising technique for non-invasive glucose monitoring. Although it is possible to find related literature to in-vitro and in-vivo experiments, no clear information is available regarding the precision of the measurements. In this paper, we address the problem of the precision due to d...

In this paper an approach to develop a non-invasive glucose measured system based on the best linear approximation (BLA) and electrical impedance spectroscopy (EIS) is presented. In order to test the advantages of the technique, three blood components at reference blood concentration are tested. In these solutions the level of glucose was varied fr...

In this paper a new approach for non-invasive glucose measurements is proposed. The new technique is based on Dielectric Spectroscopy and uses a potentiostat sensor to detect the glucose levels. As an excitation signal, random phase multisines are used. These allow scanning the level of glucose over a wide frequency range. First tests on human albu...

A software system as a support for the differential diagnostics of wide complex tachycardia based on the Bayesian diagnostic clinical methodology is presented. The system has different modules to: a) Detect complexes, with Sensibility (Sn) of 94% and Predictive Positive value (VP+) of 97.5%. b) Compute the duration of the complex, with root mean sq...