Roberto Leonarduzzi's Academic Website
Post-doctoral researcher
Signaux, Systèmes et Physique (SISYPHE) team
Laboratoire de Physique,
CNRS UMR 5672,
ENS de Lyon, France
Contact
| Address: | Ecole Normale Supérieure de Lyon |
| Laboratoire de Physique (UMR 5672 CNRS) | |
| 46 allée d'Italie 69364 Lyon Cedex 07, France | |
| Office: | LR 1 51 |
| Phone: | +33 04 72 72 85 59 |
| Email: |
Research
My research deals essentially with the analysis of highly irregular data through the notions of scale invariance and
multifractal analysis.
Recently, I also started exploring applications of the scattering transform.
I am also interested in machine learning techniques for sparse learning.
Research Interests
- Scale Invariance
- Multifractal Analysis
- Scattering Transform
- Stochastic Processes
- Biomedical Applications
- Heart rate variability (adult and fetal)
- Voice period
Tools and Methods
- Wavelet transforms
- Wavelet leader and p-leader multifractal formalism
- Scattering transform
- Machine learning: sparse classifiers
Applications
Intrapartum fetal heart rate
Acydosis detection during labor using multifractal analysis.
Adult heart rate
Characterization of ischemic strokes from heart rate under atrial fibrillation.
Artistic paintings
Author authentification of van Gogh's paintings and Raphael's drawings.
Publication List
Last updated: 2018-06-29
Journal articles
- , P. Abry, H. Wendt, S. Jaffard and H. Touchette
A Generalized Multifractal Formalism for the Estimation of Nonconcave Multifractal Spectra
IEEE Transactions on Signal Processing, vol XX, pp XX, 2018, submitted.
|||pdf| - P. Abry, J. Spilka, , V. Chudáček, N. Pustelnik and M. Doret
Sparse learning for Intrapartum fetal heart rate analysis
Biomedical Physics and Engineering Express, vol 4, pp 034002, 2018.
doi:10.1088/2057-1976/aabc64||| - , H. Liu and Y. Wang
Scattering Transform and Sparse Linear Classifiers for Art Authentication
Signal Processing, vol 150, pp 11-19, 2018.
doi:10.1016/j.sigpro.2018.03.012|||pdf| - S. Jaffard, S. Seuret, H. Wendt, , S. Roux and P. Abry
Multivariate multifractal analysis
Applied and Computational Harmonic Analysis, vol XX, pp XX, 2018, in press.
doi:10.1016/j.acha.2018.01.004|||pdf| - , P. Abry, H. Wendt, K. Kiyono, Y. Yamamoto, E. Watanabe and J. Hayano
Scattering Transform of Heart Rate Variability for the Prediction of Ischemic Stroke in Patients with Atrial Fibrillation
Methods of Information in Medicine, vol 57, pp 141-145, 2018.
doi:10.3414/ME17-02-0006|||pdf| - , P. Abry, H. Wendt, S. Jaffard and C. Melot
Finite-Resolution Effect in p-leader Multifractal Analysis
IEEE Transactions on Signal Processing, vol 65, pp 3359–3368, 2017.
doi:10.1109/TSP.2017.2690391|||pdf| - J. Spilka, J. Frecon, , N. Pustelnik, P. Abry and M. Doret
Sparse Support Vector Machine for Intrapartum Fetal Heart Rate Classification
IEEE Journal of Biomedical and Health Informatics, vol 21, pp 664-671, 2017.
doi:10.1109/JBHI.2016.2546312|||pdf| - S. Jaffard, C. Melot, , H. Wendt, P. Abry, S. G. Roux and M. Torres
p-exponent and p-leaders, Part I: Negative Pointwise Regularity.
Physica A, vol 448, pp 300–318, 2016.
doi:10.1016/j.physa.2015.12.061|||pdf| - , H. Wendt, P. Abry, S. Jaffard, C. Melot, S. G. Roux and M. Torres
p-exponent and p-leaders, Part II: Multifractal Analysis. Relations to Detrended Fluctuation Analysis.
Physica A, vol 448, pp 319–339, 2016.
doi:10.1016/j.physa.2015.12.035|||pdf| - , G. Alzamendi, G. Schlotthauer and M. Torres
Wavelet Leader Multifractal Analysis of Period and Amplitude Sequences from Sustained Vowels
Speech Communication, vol 72, pp 1–12, 2015.
doi:10.1016/j.specom.2015.04.004|||pdf| - , M. Torres and P. Abry
Scaling Range Automated Selection for Wavelet Leader Multifractal Analysis
Signal Processing, vol 105, pp 243–257, 2014.
doi:10.1016/j.sigpro.2014.06.002|||pdf|
Refereed book chapters
- P. Abry, S. Jaffard, , C. Melot and H. Wendt
New Exponents for Pointwise Singularities Classification
Proc. Fractals and Related Fields III, 19-26 September 2015, Porquerolles, France, Stéphane Seuret and Julien Barral, pp 1–38, 2017.
||| - S. Jaffard, P. Abry, C. Melot, and H. Wendt
Multifractal Analysis Based on p-exponents and Lacunarity Exponents
Fractal Geometry and Stochastics V (Progress in probability), vol 70, C. Bandt, K. Falconer, M. Zähle, pp 279-313, 2015.
|||pdf|
Refereed conference proceedings
- , P. Abry, S. Roux, H. Wendt, S. Jaffard and S. Seuret
On multifractal characterization for bivariate data
Proc. European Signal Proc. Conf. (EUSIPCO), 2018, To appear.
||| - H. Wendt, , P. Abry, S. Roux, S. Jaffard and S. Seuret
Assessing cross-dependencies using bivariate multifractal analysis
Proc. IEEE Int. Conf. Acoust., Speech, and Signal Proc. (ICASSP), 2018.
||| - , P. Abry, S. Jaffard, H. Wendt, L. Gournay, T. Kyriacopoulou, C. Martineau and C. Martinez
p-Leader Multifractal Analysis for Text Type Identification
Proc. IEEE Int. Conf. Acoust., Speech, and Signal Proc. (ICASSP), 2017.
doi:10.1109/ICASSP.2017.7953040|||pdf| - , P. Abry, H. Wendt, K. Kiyono, Y. Yamamoto, E. Watanabe and J. Hayano
Scattering Transform of Heart Rate Variability for the Prediction of Ischemic Stroke in Patients with Atrial Fibrillation
Proc. Int. Workshop Biosignal Interpretation (BSI), Osaka, Japan, 2016.
|||pdf| - J. Spilka, , V. Chudáček, P. Abry and M. Doret
Fetal Heart Rate Classification: First vs Second Stage of Labor
Proc. Int. Workshop Biosignal Interpretation (BSI), Osaka, Japan, 2016.
|||pdf| - , H. Touchette, H. Wendt, P. Abry and S. Jaffard
Generalized Legendre Transform Multifractal Formalism for Nonconcave Spectrum Estimation
2016 IEEE Statistical Signal Processing Workshop (SSP) (SSP 2016), pp 1-5, Palma de Mallorca, Spain, 2016.
doi:10.1109/SSP.2016.7551763|||pdf| - J. Spilka, V. Chudáček, M. Huptych, , P. Abry and M. Doret
Intrapartum Fetal Heart Rate Classification: Cross-Database Evaluation
XIV Mediterranean Conference on Medical and Biological Engineering and Computing: MEDICON 2016, pp 1199–1204, 2016.
doi:10.1007/978-3-319-32703-7_232|||pdf| - , H. Wendt, S. Jaffard and P. Abry
Pitfall in Multifractal Analysis of Negative Regularity
Proc. GRETSI Symposium Signal and Image Processing, Lyon, France, 2015.
|||pdf| - J. Spilka, J. Frecon, , N. Pustelnik, P. Abry and M. Doret
Intrapartum Fetal Heart Rate Classification from Trajectory in Sparse SVM Feature Space
Proc. Ann. Int. Conf. IEEE Eng. Med. and Biol. Soc. (EMBC), pp 2335–2338, 2015.
doi:10.1109/EMBC.2015.7318861|||pdf| - , J. Spilka, J. Frecon, H. Wendt, N. Pustelnik, S. Jaffard, P. Abry and M. Doret
P-leader Multifractal Analysis and Sparse SVM for Intrapartum Fetal Acidosis Detection
Proc. Ann. Int. Conf. IEEE Eng. Med. and Biol. Soc. (EMBC), pp 1971–1974, 2015.
doi:10.1109/EMBC.2015.7318771|||pdf| - , J. Spilka, H. Wendt, S. Jaffard, M. Torres, P. Abry and M. Doret
p-leader Based Classification of First Stage Intrapartum Fetal HRV
Proc. Latin American Conference on Biomedical Engineering (CLAIB), Paraná, Argentina, 2014.
doi:10.1007/978-3-319-13117-7_129|||pdf| - , H. Wendt, S. Jaffard, S. Roux, M. Torres and P. Abry
Extending Multifractal Analysis to Negative Regularity: p-exponents and p-leaders
Proc. IEEE Int. Conf. Acoust., Speech, and Signal Proc. (ICASSP), pp 305-309, Florence, Italy, 2014.
doi:10.1109/ICASSP.2014.6853607|||pdf| - , G. Schlotthauer and M. Torres
Wavelet Leader Based Multifractal Analysis of Heart Rate Variability during Myocardial Ischaemia
Proc. Ann. Int. Conf. IEEE Eng. Med. and Biol. Soc. (EMBC), pp 110–113, 2010.
doi:10.1109/IEMBS.2010.5626091|||pdf|
Invited talks
-
Scattering transform for art investigations
Séminaire Cristolien d'Analyse Multifractale, Université Paris-Est Créteil
Creteil, France. May 2018. link -
p-leader analysis and classification of oscillating singularities
CIMPA 2017 Research School: Harmonic Analysis, Geometric Measure Theory and Applications
Buenos Aires, Argentina. August 2017. link -
Multifractal analysis for text type identification
Séminaire Cristolien d'Analyse Multifractale, Université Paris-Est Créteil
Creteil, France. April 2017. link -
p-leader analysis and classification of oscillating singularities
Journées du GDR Multifractale
Avignon, France. September 2016. link -
p-leader multifractal analysis: advantages and applications
Fractals and Related Fields III
Porquerolles, France. September 2015. link
Software
mf_bs_tool: P-leader multifractal analysis
This MATLAB toolbox implements multifractal analysis methods based on wavelet leaders and p-leaders, as described in (Wendt et al. 2007), (Wendt et al. 2009), (Jaffard et al. 2016), and (Leonarduzzi et al. 2016).
Main features:
- User-friendly class-based interface
- Analysis of 1D data or grayscale images.
- Estimation of scaling function, multifractal spectrum, and log-cumulants.
- Choice of multiresolution quantities: wavelet coefficients, leaders, p-leaders, MF-DFA.
- Bootstrap based confidence intervals and tests.
- Automatic selection of scaling range (Leonarduzzi et al. 2014).
- Automatic analysis of a collection of data (folder, file list, Monte Carlo simulation)
- Detailed demos for all toolbox features
The toolbox is written entirely in Matlab, with a key section in C that can be optionally compiled for improved speed and memory performance.
Demo
rangesel: Scaling range selection
This software is outdated. A new version is bundled in the p-leader based multifractal analysis toolbox presented before.
Performs the bootstrap-based scaling range selection algorithm for wavelet leader multifractal analysis, as described in this paper. Works with legacy versions of the wavelet-leader multifractal analysis toolbox WLBMF.
matlab_fig_printing
Matlab toolbox for convenient printing of publication quality figures.
Main features:
- Simple interface for printing.
- Creation of figure of actual size, that needs not be scaled when included in the document.
- Fixed font size in all text within the figure to ensure it remains readable when included.
- Automatic cropping of margins.
Vita
Download full CV: .pdf
Personal data
- Birth: January 4, 1985
- Nationality: Argentine / Italian
Languages
- Spanish: mother tonge
- English: fluent (oral and written)
- French: intermediate (oral and written)
Education
- 2014: PhD in Engineering, National Univerity of Litoral, Argentina.
Specialty: Signals, Systems and Computational Inteligence
Thesis: Wavelet-leader-based multifractal analysis: automatic scaling range selection, p-leader-based multifractal formalism and application to biomedical signals. - 2010: Biomedical Engineer, National Univerity of Entre Ríos, Argentina
Career
- Current: Postdoctoral Fellow, Laboratoire de Physique, CNRS UMR 5672, ENS de Lyon, France
- May 2017-October 2017: Visiting Scholar, Department of Mathematics, The Hong Kong University of Science and Technology.
- 2015-2017: Postdoctoral Fellow, Laboratoire de Physique, CNRS UMR 5672, ENS de Lyon, France
Awards
- 2010: first place, CORAL-EMBS Student Paper Competition. 32 IEEE Engineering in Medicine and Biology Conference Society
- 2010: Award to the Best Engineering Graduates, National Engineering Academy, Argentina