RIX , Hervé

(Signal-shape processing in analytical chemistry.) When signal evolution (e.g., spectra) has to be detected or measured, shape processing can be useful. The distribution function method enables all the information in the signal shape to be utilized, by working with normalized integrals. The concept of shape also helps in estimating resolution...

The ECG signal digitised with a high resolution level (HR ECG) is a non invasive way more and more used in clinical centres to analyze heart electrical activity. The Signal Averaging technique is commonly used to eliminate the noisy part of the recordings. A synthesis of some of our published works is presented with the aim to take into account...

A new simple method is proposed for the separation of two strongly overlapped peaks assuming the hypothesis that the two component profiles are the same shape. The single peak profile and the double one must be available. The proposed method does not belong to classical deconvolution nor model fitting methods. Looking at simulation results...

International audience

The recognition of a given shape in a positive signal using the Distribution Function Method (DFM) assumes an affine transform on the abscissa and only a multiplicative coefficient on the ordinates, without any offset. The aim of the paper is to extent DFM when shape equality includes an offset. In fact, this problem is a particular case of...

Integral Shape Averaging (ISA) is a technique for averaging a series of positive signals using their normalized integrals. In case of equal shape signals, ISA gives an estimation of this shape with an increased SNR due to integration. A new application of ISA is presented here: from only one recording of a positive signal embedded in noise,...

The detection of an impurity in a visually single peak by means of the "Distribution Function Method" necessitates a thorough control of every parameter which influences the shape of a peak. In particular, the heights of the peaks compared must be as equal as possible when the chromatographic response is not a linear function of the injected...

(Time delay estimation for equal shape signals) An original method in order to estimate the time delay between two equal shape signals is presented. This method combined with the classical averaging of time-locked measurements, makes it possible to extract a deterministic signal from a random noise.

The aim of this paper is to describe the analysis of a high resolution ECG recorded from the body surface. Standard signal averaging techniques are improved by using a new time delay estimation method which leads to a better alignment accuracy of P and T waves. A second method uses adaptive identification to achieve a beat by beat fine ECG...

The variability of a set of biomedical signals is analysed following some criterions. Firstly, when the signal source is unique, the variability may be, for one sensor in function of the time occurrence of the signals, for several sensors at the same time, a spatial variability. The case of several sources corresponds to the inter subject...

International audience

International audience

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The contribution of two substances may result in a chromatographic signal (in gas chromatography) whose shape is a single peak. This happens when the relative concentration of the two substances R and the difference between their retention times M are small enough. A criterion is proposed which, applied to a signal whose shape is a single peak,...

The "Distribution Function Method", which makes possible the measurement of systematic variations in the shape of signals, has been experimentally tested on the detection of two visually confounded gas chromatographic peaks, irrespective of the estimation of the resolution or the concentration ratio. Two detection procedures are suggested. The...

A method for the detection of very small differences between the shapes of two signals is presented. This method uses the normalized integrals of the signals to be compared; hence it filters the noise. After a general presentation giving an especially detailed account of the definition of equality of two shapes, the possible application fields...

International audience

T waves properties are not usually fully exploited when analyzing its profile variation within a set of records. An affine transform of the temporal support is a good candidate for the modeling of this variation. Based on this assumption, we propose here a new framework that provides an estimation of the reference T wave and the parameters of...

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When several realizations of an unknown recurrent signal are observed apart from a time expansion or compression, the classical way of estimating these time scaling factors is to take one signal as reference for the estimation. This approach does not take into account the common information between all possible couples of realizations. To...

International audience

International audience

International audience

Classical signal averaging is an important operation in signal processing applications but is meaningless if shape or time variability is present among the signals being averaged. Structural Average Estimation (SAE) and Integral Shape Averaging (ISA) are recent methods that deal with these types of variability by providing a "structural...