Thèses sur le sujet « Transformation du signal »
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Lemire, Isabelle. « Transformation du signal d'ancrage de l'endopeptidase neutre-24.11 en un peptide signal ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1996. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq21484.pdf.
Texte intégralCexus, Jean-Christophe. « Analyse des signaux non-stationnaires par transformation de Huang, opérateur de Teager-Kaiser et transformation de Huang-Teager (THT) ». Rennes 1, 2005. http://www.theses.fr/2005REN1S124.
Texte intégralFachrudin, Imam. « Traitement du signal ECG - approche par la transformation en ondelettes ». Rouen, 1995. http://www.theses.fr/1995ROUES040.
Texte intégralKårehed, Karin. « Signal Transduction in Malignant Cells – Transformation, Activation and Differentiation ». Doctoral thesis, Uppsala University, Department of Genetics and Pathology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6346.
Texte intégralAll aspects of cell life are regulated by signal transduction mechanisms. This thesis describes the regulatory roles of a few key signal transduction molecules involved in three major biological responses. The studied pathways include platelet derived growth factor (PDGF)-BB induced transformation of murine fibroblasts, interferon (IFN)-γ stimulated monocyte activation and all-trans retinoic acid (ATRA) induced myeloid differentiation.
We found that intact phosphoinositide 3OH-kinase (PI3K) activity is essential in the signaling pathway that leads to the morphological alterations and migration pattern characteristic of PDGF-BB transformed NIH/sis and NIH/COL1A1 fibroblasts. Furthermore, our data indicated that the small Rho-GTPase, Rac1 is the predominant mediator of these signals downstream of PI3K.
The study of the IFN-γ induced activation of monocytic U-937 cells showed that upregulation of the high affinity receptor for IgG (FcγRI) is dependent on the coordination of several regulatory events: the PKR-mediated serine 727 phosphorylation of Stat1, the expression of the hematopoietic lineage specific transcription factor PU.I, and the activation of the NFκB pathway.
ATRA-induced differentiation and cell cycle arrest are impaired in U-937 sublines expressing phosphorylation deficient Stat1 (Stat1Y701F and Stat1S727A). The findings in paper III indicated that the expression pattern of the myeloid specific transcription factors Stat2, ICSBP and c/EBPε was altered in the sublines and that intact Stat1 activation is critical for maintaining the balance of the transcriptional network during ATRA induced terminal differentiation.
Finally, ATRA-induced differentiation and growth arrest were blocked by treatment with the IKKα/β inhibitor BMS345541 or by ectopic expression of the NFκB super repressor IκBα (S32A/S36A). The fact that IκB(AA) sublines differentiated normally in response to vitamin D3, showed that NFκB inhibition specifically affected ATRA induced responses. Notably we suggest that the activity of the NFκB pathway may interfere with the differentiation process via a direct effect on the RAR/RXR mediated transcription.
Tennigkeit, Frank. « Intrinsic membrane properties affecting signal transformation in auditory thalamic neurons ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ34633.pdf.
Texte intégralFotinopoulos, Ioannis. « Root moments : a non-linear transformation technique with applications in signal processing ». Thesis, Imperial College London, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.396276.
Texte intégralMorimoto, Mai. « Signal transformation at the input and output of the Drosophila visual system ». Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/267911.
Texte intégralCheng, Wai-sheung. « PTEN-PKB in endometriosis and related malignant transformation / ». View the Table of Contents & ; Abstract, 2005. http://sunzi.lib.hku.hk/hkuto/record/B31540764.
Texte intégralJEFFRIES, SHAWN. « THE ROLE OF NUCLEAR LOCALIZATION AND N ic -PROTEIN COMPLEX FORMATION IN NOTCH INDUCED NEOPLASIA ». University of Cincinnati / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1107384497.
Texte intégralRáček, Tomáš. « Prahovací pravidla pro potlačování šumu ve zvukových signálech ». Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218274.
Texte intégralKhawaja, Antoun. « Automatic ECG analysis using principal component analysis and wavelet transformation ». Karlsruhe Univ.-Verl. Karlsruhe, 2007. http://www.uvka.de/univerlag/volltexte/2007/227/.
Texte intégralJohansson, Björn. « Multidimensional signal recognition, invariant to affine transformation and time-shift, using canonical correlation ». Thesis, Linköping University, Linköping University, Computer Vision, 1997. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-54355.
Texte intégralChapter 2 describes the concept of canonical correlation. This you have to know about in order to understand the continuing discussion.
Chapter 3 introduce you to the problem that was to be solved.
Chapter 4, 5 and 6 discusses three different suggestions how to approach the problem. Each chapter begins with a section of experiments as a motivation of the approach. Then follows some theory and mathematical manipulations to structure the thoughts. The last sections contains discussions and suggestions concerning the approach.
Finally chapter 7 contains a summary and a comparismental discussion of the approaches.
Hart, Kristen Carol. « Subcellular-localization requirements for activation of signal transduction pathways that lead to transformation / ». Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 1998. http://wwwlib.umi.com/cr/ucsd/fullcit?p9834969.
Texte intégralLiu, LiChan. « Single epoch analysis and bi-hemisphere study of magnetoencephalographic (MEG) signals using vector signal transformation V3 magnetic field tomography (MFT) ». Thesis, Open University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261057.
Texte intégralAlfonso, Ovidio. « Digital signal processing implementation for near real-time wavelet transformation system for binary images ». FIU Digital Commons, 2000. http://digitalcommons.fiu.edu/etd/1065.
Texte intégralCheng, Wai-sheung, et 鄭偉嫦. « PTEN-PKB in endometriosis and related malignant transformation ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B45009910.
Texte intégralTAKEDA, Kazuya, Norihide KITAOKA et Makoto SAKAI. « Acoustic Feature Transformation Based on Discriminant Analysis Preserving Local Structure for Speech Recognition ». Institute of Electronics, Information and Communication Engineers, 2010. http://hdl.handle.net/2237/14969.
Texte intégralVray, Didier. « Analyse et traitement d’échos ultrasonores : application à l'acoustique de la pêche ». Lyon, INSA, 1989. http://www.theses.fr/1989ISAL0010.
Texte intégralHuber, Stefan. « Voice Conversion by modelling and transformation of extended voice characteristics ». Electronic Thesis or Diss., Paris 6, 2015. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2015PA066750.pdf.
Texte intégralVoice Conversion (VC) aims at transforming the characteristics of a source speaker’s voice in such a way that it will be perceived as being uttered by a target speaker. The principle of VC is to define mapping functions for the conversion from one source speaker’s voice to one target speaker’s voice. The transformation functions of common State-Of-The-Art (START) VC system adapt instantaneously to the characteristics of the source voice. While recent VC systems have made considerable progress over the conversion quality of initial approaches, the quality is nevertheless not yet sufficient. Considerable improvements are required before VC techniques can be used in an professional industrial environment. The objective of this thesis is to augment the quality of Voice Conversion to facilitate its industrial applicability to a reasonable extent. The basic properties of different START algorithms for Voice Conversion are discussed on their intrinsic advantages and shortcomings. Based on experimental evaluations of one GMM-based State-Of-The-Art VC approach the conclusion is that most VC systems which rely on statistical models are, due to averaging effect of the linear regression, less appropriate to achieve a high enough similarity score to the target speaker required for industrial usage. The contributions established throughout this thesis work lie in the extended means to a) model the glottal excitation source, b) model a voice descriptor set using a novel speech system based on an extended source-filter model, and c) to further advance IRCAM’s novel VC system by combining it with the contributions of a) and b)
Chaouki, Saïd. « Logiciel de traitement du signal ». Rouen, 1987. http://www.theses.fr/1987ROUES024.
Texte intégralBouchikhi, Abdelkhalek. « Analyse des signaux AM-FM par Transformation d'Huang Teager : application à l'acoustique sous marine ». Phd thesis, Université Rennes 1, 2010. http://tel.archives-ouvertes.fr/tel-00818032.
Texte intégralПогребняк, Р. С. « Дослідження законів розподілу акустичних сигналів після їх функціональних перетворень ». Thesis, Сумський державний університет, 2013. http://essuir.sumdu.edu.ua/handle/123456789/43569.
Texte intégralBouchikhi, Abdelkhalek. « Analyse des signaux AM-FM par transformation de Huang-Teager : application à l'acoustique sous-marine ». Rennes 1, 2010. https://tel.archives-ouvertes.fr/tel-00818032.
Texte intégralLa Décomposition Modale Empirique (EMD) est un outil de traitement de signal piloté par les données et dédié aux signaux non-stationnaires issus ou non de systèmes linéaires. L'idée de base de l'EMD est l'interpolation des extrema par des splines pour extraire de composantes oscillantes appelées modes empiriques intrinsèques (IMFs) et un résidu. Dans cette thèse, un nouvel algorithme de l'EMD est introduit ou au lieu d'une interpolation rigide, un lissage est utilise pour la construction des enveloppes supérieures et inferieures du signal à décomposer. Ce nouvel algorithme est plus robuste au bruit que l'EMD conventionnelle et réduit le nombre d'IMFs "artificielles" (sur-décomposition). En combinant le nouvel algorithme et la méthode de séparation d'énergie (ESA) basée sur l'Operateur d'Energie de Teager-Kaiser (OETK), un nouveau schéma de démodulation des signaux AM-FM multi-composante appelé EMD-ESA est introduit. Différentes versions de l'EMD-ESA sont analysées en terme de performance. Pour l'analyse Temps-Fréquence (TF), une nouvelle formulation de la carte TF de l'EMD-ESA appelée Transformation de Teager-Huang (THT) est présentée. Cette nouvelle Représentation TF (RTF) ne présentant pas de termes d'interférences est comparée aux RTF classiques telles que le spectrogramme, le scalogramme, la distribution de Wigner-Ville Distribution (WVD), la Pseudo-WVD et la réallocation de la Pseudo-WVD. En combinant la nouvelle formulation de la THT et la transformée de Hough, une nouvelle méthode de détection des signaux multi-composante à modulation linéaire de fréquence dans le plan TF est présentée. Cette méthode de détection est appelée transformation de Teager-Huang-Hough (THHT). Les résultats de la THHT sont compares a ceux de la transformée WVD-Hough. Finalement, l'analyse TF par THT et par des RTF classiques (WVD,') de signaux réels de rétrodiffusion par des coques cylindriques de dimensions et de caractéristiques physiques différentes est présentée. Les résultats obtenus montrent l'apport de la THT comme un outil TF
Ji, Soo-Yeon. « COMPUTER-AIDED TRAUMA DECISION MAKING USING MACHINE LEARNING AND SIGNAL PROCESSING ». VCU Scholars Compass, 2008. http://scholarscompass.vcu.edu/etd/1628.
Texte intégralHeyne, Benjamin. « Efficient CORDIC based implementation of selected signal processing algorithms ». Aachen Shaker, 2008. http://d-nb.info/991790073/04.
Texte intégralTanguy, Noël. « La transformation de Laguerre discrète ». Phd thesis, Université de Bretagne occidentale - Brest, 1994. http://tel.archives-ouvertes.fr/tel-00438350.
Texte intégralDegottex, Gilles. « Glottal source and vocal-tract separation : estimation of glottal parameters, voice transformation and synthesis using a glottal model ». Paris 6, 2010. http://www.theses.fr/2010PA066399.
Texte intégralWinkler, Christophe. « Expérimentation d'algorithmes de calcul de radiosité à base d'ondelettes ». Vandoeuvre-les-Nancy, INPL, 1998. http://www.theses.fr/1998INPL071N.
Texte intégralLangari, Bahareh. « Multi-scale edge-guided image gap restoration ». Thesis, Brunel University, 2016. http://bura.brunel.ac.uk/handle/2438/13406.
Texte intégralThureau, Pierre. « RMN [Résonance Magnétique Nucléaire] DOSY [Diffusion Ordered SpectroscopY] : comparaison des méthodes de traitement et application à l'échange chimique ». Aix-Marseille 1, 2006. http://www.theses.fr/2006AIX11032.
Texte intégralThis thesis can be viewed as the state-of-the-art of Diffusion Ordered NMR SpectroscopY (DOSY). More precisely we described various approaches to analyze the data so that the information obtained from the mixture analysis can be maximized. The limitations of the different methods and the perturbation arising from chemical exchange are also discussed. In the first part of the manuscript, we describe the numerical problems arising from NMR diffusion data processing and compare several methods available in the literature for avoiding such problems. In addition, pulse sequences and methodologies, will be discussed herein. Finally, we describe the perturbation induced by the chemical exchange on NMR diffusion experiments and how this perturbation can be used to extract precisely the exchange rate constant. With the help of these techniques, the hydration properties of the pyrimidine bases have been probed
Gehin, Martine. « Rôle du coactivateur TIF2 dans la transduction du signal des récepteurs nucléaires in vivo ». Université Louis Pasteur (Strasbourg) (1971-2008), 2001. http://www.theses.fr/2001STR13177.
Texte intégralArdaillon, Luc. « Synthesis and expressive transformation of singing voice ». Electronic Thesis or Diss., Paris 6, 2017. http://www.theses.fr/2017PA066511.
Texte intégralThis thesis aimed at conducting research on the synthesis and expressive transformations of the singing voice, towards the development of a high-quality synthesizer that can generate a natural and expressive singing voice automatically from a given score and lyrics. Mainly 3 research directions can be identified: the methods for modelling the voice signal to automatically generate an intelligible and natural-sounding voice according to the given lyrics; the control of the synthesis to render an adequate interpretation of a given score while conveying some expressivity related to a specific singing style; the transformation of the voice signal to improve its naturalness and add expressivity by varying the timbre adequately according to the pitch, intensity and voice quality. This thesis provides some contributions in each of those 3 directions. First, a fully-functional synthesis system has been developed, based on diphones concatenations. The modular architecture of this system allows to integrate and compare different signal modeling approaches. Then, the question of the control is addressed, encompassing the automatic generation of the f0, intensity, and phonemes durations. The modeling of specific singing styles has also been addressed by learning the expressive variations of the modeled control parameters on commercial recordings of famous French singers. Finally, some investigations on expressive timbre transformations have been conducted, for a future integration into our synthesizer. This mainly concerns methods related to intensity transformation, considering the effects of both the glottal source and vocal tract, and the modeling of vocal roughness
Hirrle, Angelika. « Zur Reduzierung des mehrwegebedingten GNSS-Trägerphasenmessfehlers durch Anwendung der Hilbert-Huang-Transformation auf Signalqualitätsparameter ». Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-223922.
Texte intégralBourdier, Renaud. « Analyse temps/frequence, filtrage et synthese numeriques de signaux de parole : application au filtrage, a la reduction de bruit et a la restauration d'enregistrements anciens ». Le Mans, 1988. http://www.theses.fr/1988LEMA1001.
Texte intégralGreene, Howard L. « Characterization of the light to horizontal cell signal transformation in the tiger salamander retina under varying states of dark adaptation / ». The Ohio State University, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487847761308738.
Texte intégralVenkateswaran, Anjli. « RET/PTC1-mediated phosphotyrosine signaling pathways involved in thyroid cell transformation ». Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1100117850.
Texte intégralTitle from first page of PDF file. Document formatted into pages; contains xvi, 157 p.; also includes graphics (some col.) Includes bibliographical references (p. 146-157).
Zheng, Xincheng. « Two-signal requirement for the development of T lymphocytes ». Connect to this title online, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1109258062.
Texte intégralTitle from first page of PDF file. Document formatted into pages; contains xvi, 156 p.; also includes graphics (some col.) Includes bibliographical references (p. 127-156). Available online via OhioLINK's ETD Center
Bavikadi, Sathwika, et Venkata Bharath Botta. « Estimation and Correction of the Distortion in Forensic Image due to Rotation of the Photo Camera ». Thesis, Blekinge Tekniska Högskola, Institutionen för tillämpad signalbehandling, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-15965.
Texte intégralGrave, Xavier. « Etude de methodes pour la recherche, avec le detecteur virgo d'ondes gravitationnelles emises par des etoiles a neutrons ». Paris 11, 1997. http://www.theses.fr/1997PA112105.
Texte intégralHamaoui, Daniel. « Étude du rôle de l’Optineurine dans l’axe de signalisation HACE1/Rac1 et la transformation tumorale ». Thesis, Université Côte d'Azur (ComUE), 2016. http://www.theses.fr/2016AZUR4092/document.
Texte intégralWe have established a novel regulatory mechanism that restricts Rac1 activity through ubiquitylation and targeting to the proteasome of the active form of the GTPase for degradation and signal termination. This regulation is dominant over the classical GEF/GAP cycle of regulation. We identified the E3 ubiquitin ligase (E3L) HACE1 as the main enzyme that catalyzes Rac1 ubiquitylation. HACE1 is a major tumor suppressor that limits Rac-dependent NADPH oxidase complex activity, S phase entry, cell migration, mammary cell transformation and tumor growth in animal models. In order to determine how HACE1 activity is controlled, we conducted a whole genome two-hybrid screen and identified Optineurin (OPTN) as a primary partner of the E3L HACE1. We report that OPTN is a new Extracellular matrix (ECM) stiffness sensor that activates HACE1 E3L activity. OPTN controls adhesion-mediated ubiquitin-proteasome degradation of Rac1 to tune Rac1 signaling with tissue stiffness. Loss of OPTN is associated with a gain of cell-ECM adhesive properties and enhanced integrin-mediated proliferative signaling and metabolic activity. Interestingly, cells that loose OPTN display atypical mechanical properties and apparent uncoupling of Focal Adhesions growth from acto-myosin contractile activity. Together, our findings establish the first link between the Rac1 ubiquitylation pathway and ECM compliance sensing and define OPTN as a previously unknown mechanical sensor. OPTN and HACE1 would then act as a tumor-suppressor complex that adapts cell proliferative response to ECM mechanical properties in order to insure both Tensional integrity and Redox homeostasis of cells
Ardaillon, Luc. « Synthesis and expressive transformation of singing voice ». Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066511/document.
Texte intégralThis thesis aimed at conducting research on the synthesis and expressive transformations of the singing voice, towards the development of a high-quality synthesizer that can generate a natural and expressive singing voice automatically from a given score and lyrics. Mainly 3 research directions can be identified: the methods for modelling the voice signal to automatically generate an intelligible and natural-sounding voice according to the given lyrics; the control of the synthesis to render an adequate interpretation of a given score while conveying some expressivity related to a specific singing style; the transformation of the voice signal to improve its naturalness and add expressivity by varying the timbre adequately according to the pitch, intensity and voice quality. This thesis provides some contributions in each of those 3 directions. First, a fully-functional synthesis system has been developed, based on diphones concatenations. The modular architecture of this system allows to integrate and compare different signal modeling approaches. Then, the question of the control is addressed, encompassing the automatic generation of the f0, intensity, and phonemes durations. The modeling of specific singing styles has also been addressed by learning the expressive variations of the modeled control parameters on commercial recordings of famous French singers. Finally, some investigations on expressive timbre transformations have been conducted, for a future integration into our synthesizer. This mainly concerns methods related to intensity transformation, considering the effects of both the glottal source and vocal tract, and the modeling of vocal roughness
Bouchebaba, Youcef. « Optimisation des transferts de données pour le traitement du signal : pavage, fusion et réallocation des tableaux ». Paris, ENMP, 2002. http://www.theses.fr/2002ENMP1101.
Texte intégralFirouzmand, Mohammad. « Modélisation sinusoïdale à long terme du signal de parole ». Phd thesis, Grenoble INPG, 2007. http://www.theses.fr/2007INPG0038.
Texte intégralThe sinusoidal modeling of speech signaIs is usually defined on a "short term" basis, i. E. On successive frames of about 10 to 30 ms. This thesis brings a new contribution to this domain by adding to this traditional level spectral modeling an additionnal level along the temporal axis: we model the trajectories of sinusoidal parameters over durations significantly longer than the short-term frames (several hundreds of ms). Ln this study, we propose to use various long term models based on discrete cosine functions and polynomials. The adjustment to the trajectories is carried out by a weighted minimum mean square error regression, the weights of the regression being determined by perceptive criteria. For this task, a series of iterative algorithms is proposed and tested. The 101 term method is shown to be an efficient and parsimonious approach to describe the dynamics of the speech signal
Firouzmand, Mohammad. « Modélisation Sinusoïdale à Long Terme du Signal de Parole ». Phd thesis, Grenoble INPG, 2007. http://tel.archives-ouvertes.fr/tel-00211294.
Texte intégralDey, Ajoy Kumar, et Susmita Saha. « Acoustic Beamforming : Design and Development of Steered Response Power With Phase Transformation (SRP-PHAT) ». Thesis, Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-3226.
Texte intégralBassani, Thiago. « Design of a BCI system using EEG signal analysis with continuous wavelet transformation and Naïves bayes classifier / Thiago Bassani ; orientador, Julio Cesar Nievola ». reponame:Biblioteca Digital de Teses e Dissertações da PUC_PR, 2009. http://www.biblioteca.pucpr.br/tede/tde_busca/arquivo.php?codArquivo=1482.
Texte intégralBibliografia: f. 47-52
Uma das questões mais importantes na interface de computador-cérebro é a análise de padrões cerebrais, geralmente representados por sinais elétricos. Este trabalho tem como objetivo introduzir uma ferramenta de mineração de dados para sinais de EEG, anali
One of the most important issues in brain-computer interface (BCI) is the analysis of patterns in brain states generally represented by electrical signals. The main objective of this work is to present an exploratory approach on electroencephalographic (E
Le, Ber Catherine. « Simulation sur ordinateur d'un système linéaire continu et stationnaire ». Brest, 1988. http://www.theses.fr/1988BRES2020.
Texte intégralGrisel, Richard. « Détectabilité du nombre de sources en sonar ». Rouen, 1987. http://www.theses.fr/1987ROUES011.
Texte intégralSavaton, Guillaume. « Méthodologie de conception de composants virtuels comportementaux pour une chaîne de traitement du signal embarquée ». Phd thesis, Université de Bretagne Sud, 2002. http://tel.archives-ouvertes.fr/tel-00003048.
Texte intégralBeya, Ouadi. « Analyse et reconnaissance de signaux vibratoires : contribution au traitement et à l'analyse de signaux cardiaques pour la télémédecine ». Thesis, Dijon, 2014. http://www.theses.fr/2014DIJOS015/document.
Texte intégralThe heart is a muscle. Its mechanical operation is like a pump charged for distributing and retrieving the blood in the lungs and cardiovascular system. Its electrical operation is regulated by the sinus node, a pacemaker or electric regulator responsible for triggering the natural heart beats that punctuate the functioning of the body.Doctors monitor the electromechanical functioning of the heart by recording an electrical signal called an electrocardiogram (ECG) or an audible signal : the phonocardiogram (PCG). The analysis and processing of these two signals are essential for diagnosis, to help detect anomalies and cardiac pathologies.The objective of this thesis is to develop signal processing tools on ECG and PCG to assist cardiologist in his analysis of these signals. The basic idea is to develop algorithms of low complexity and having inexpensive computing time. The primary interest is to ensure their easy implementation in a mobile heart monitoring system for use by the doctor or the patient. The second advantage lies in the possibility of automatic real-time analysis of signals with the mobile device, allowing control of the transmission of these signals to a removal of doubt.Numerous studies have led to significant advances in the analysis of ECG signals and the automatic recognition of cardiac conditions. Databases of real or synthetic signals annotated also assess the performance of new methods. PCG signals are much less studied, difficult to analyze and to interpret. The main methods (Fourier, wavelet and Wigner Ville) were tested : they do not allow automatic recognition of signatures, and an accurate understanding of their contents.Wavelet Transform (WT) on cardiac signals showed its effectiveness to filter and locate useful information, but it involves an external processing function (mother wavelet) whose the choice depends on the prior knowledge on the signal to be processed. This is not always suitable for cardiac signals. Moreover, the wavelet transform generally induces inaccuracies in the location due to the external function and optionally due to the sub- sampling of the signatures.The non-stationary nature of the ECG and PCG and their sensitivity to noise makes it difficult to separate an informative transition of a transition due to measurement noise. The choice of treatment tool should allow denoising and analysis of these signals without alteration or the processing tool delocalization of the singularities.In response to our objectives and considering these problems, we propose to rely primarily on empirical mode decomposition (EMD) and Hilbert Huang Transform (HHT) to develop solutions. The EMD is a non linear approach decomposing the signal in intrinsic signal (IMF), oscillations of the type FM-AM, giving a time/scale signal representation. Associated with the Hilbert transform (TH), the THH determines the instantaneous amplitude (IA) and instantaneous frequency (IF) of each mode, leading to a time/frequency representation of the ECG and PCG.Without involving an external function, EMD approach can restore (noise reduction), analyze and reconstruct the signal without relocation of its singularities. This approach allows to locate R peaks of the ECG, heart rate and study the cardiac frequency variability (CFV), locate and analyze the sound components B1 and B2 of the PCG.Among the trials and developments that we made, we present in particular a new method (EDA : empirical denoising approach) inspired by the EMD approach for denoising cardiac signals. We also set out the implementation of two approaches for locating ECG signature (QRS complex, T and P waves). The first is based on the detection of local maxima : in using Modulus Maxima and Lipschitz exponent followed by a classifier. The second uses NFLS, wich an nonlinear approach for the detection and location of unique transitions in the discrete domain