Дисертації з теми "PCG signals"
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Жемчужкіна, Т. В., and Т. В. Носова. "Construction of bispectra for PCG signals." Thesis, НТУ «ХПІ», 2021. https://openarchive.nure.ua/handle/document/17555.
Повний текст джерелаАнотація:
To construct bispectra for separate segments of PCG such as sounds and murmurs we applied segmentation method based on averaged Shannon envelope. We got bispectrums of sounds and murmurs for different signals: normal and pathological. It can be seen that bispectra are non-zero, so signals are non-Gaussian. There is phase coupling between each two frequencies for each bispectrum. And also, the patterns for bispectra for each person are different in all groups.
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Жемчужкіна, Т. В., та Т. В. Носова. "Сonstruction of phase portraits of PCG signals". Thesis, НТУ «ХПІ», 2021. https://openarchive.nure.ua/handle/document/17554.
Повний текст джерелаАнотація:
For PCG signals we constructed phase portraits (PP) in 2-dimensional state space. To demonstrate PP of heart sounds and murmurs we extracted main sounds from PCG signals. Different signals have different forms of PP and samples of main sounds can be separated from rest samples using PP. Showed applications of PP analysis. So, PP of PCG signals probably can be used for diagnostics of heart sounds and for segmentation of PCG signal without simultaneous ECG-recording.
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Daura, Ashiru Sani. "A wavelet-based method for the classification of PCG signals." Thesis, University of Newcastle Upon Tyne, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244474.
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Giacotto, Luca. "Signal integrity at PCB level." Université Joseph Fourier (Grenoble), 2003. http://www.theses.fr/2003GRE10075.
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Bondurant, Philip D., and Andrew Driesman. "Smart PCM Encoder." International Foundation for Telemetering, 1995. http://hdl.handle.net/10150/611601.
Повний текст джерелаАнотація:
International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, NevadaIn this paper, a new concept in PCM telemetry encoding equipment is described. Existing "programmable" PCM encoders allow only simple changes in the functionality of the hardware, such as input gain, offset, and word formatting. More importantly, these encoders do not provide capability for "in-flight" processing of signals and in general have not taken advantage of existing hardware and software digital signal processing technology. In-flight processing of signals can provide a significant reduction in the required transmission bandwidth, allowing additional data that may not have otherwise been transmitted to be sent on the telemetry channel. A modular digital signal processor (DSP) based PCM encoder architecture is described that has a set of on-board processing algorithms configurable via a simple-to-use graphical user interface. Algorithms included are compression (lossy and lossless), Fourier transforms of various resolutions (typically followed by peak detection to provide a data rate reduction), extreme values (max, min, rms), time filtering, regression, trajectory prediction, and serial data stream processing. Custom algorithms can be developed and included as part of the suite of processing algorithms. The preprocessing algorithms exist as firmware on the DSPs and can accommodate as many different signals as the processing bandwidth of the DSP can handle. Typically one DSP can handle many input signals and different algorithms. The encoder is programmable via a standard RS-232 serial interface allowing the signal input configuration, telemetry frame layout, and on-board processing algorithms to be changed quickly.
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Noorzadeh, Saman. "Extraction de l'ECG du foetus et de ses caractéristiques grâce à la multi-modalité." Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAT135/document.
Повний текст джерелаАнотація:
La surveillance de la santé foetale permet aux cliniciens d’évaluer le bien-être du foetus,de faire une détection précoce des anomalies cardiaques foetales et de fournir les traitementsappropriés. Les développements technologies actuels visent à permettre la mesurede l’électrocardiogramme (ECG) foetal de façon non-invasive afin d’extraire non seulementle rythme cardiaque mais également la forme d’onde du signal. Cet objectif est rendudifficile par le faible rapport signal sur bruit des signaux mesurés sur l’abdomen maternel.Cette mesure est donc toujours un challenge auquel se confrontent beaucoup d’études quiproposent des solutions de traitement de signal basées sur la seule modalité ECG.Le but de cette thèse est d’utiliser la modélisation des processus Gaussiens pour améliorerl’extraction des signaux cardiaques foetaux, dans une base multi-modale. L’ECG est utiliséconjointement avec le signal Phonocardiogramme (PCG) qui peut apporter une informationcomplémentaire à l’ECG. Une méthode générale pour la modélisation des signauxquasi-périodiques est présentée avec l’application au débruitage de l’ECG et à l’extractionde l’ECG du foetus. Différents aspects de la multi-modalité (synchronisation, · · · ) proposéesont étudiées afin de détecter avec plus de robustesse les battements cardiaques foetaux.La méthode considère l’application sur les signaux ECG et PCG à travers deux aspects:l’aspect du traitement du signal et l’expérimental. La modélisation des processus Gaussien,avec le signal PCG pris comme la référence, est utilisée pour extraire des modèles flexibleset des estimations non linéaires de l’information. La méthode cherche également à faciliterla mise en oeuvre pratique en utilisant un codage 1-bit des signaux de référence.Le modèle proposé est validé sur des signaux synthétiques et également sur des donnéespréliminaires réelles qui ont été enregistrées afin d’amorcer la constitution d’une base dedonnées multi-modale synchronisée. Les premiers résultats montrent que la méthode permettraà terme aux cliniciens d’étudier les battements cardiaques ainsi que la morphologiede l’ECG. Ce dernier aspect était jusqu’à présent limité à l’analyse d’enregistrements ECGinvasifs prélevés pendant l’accouchement par le biais d’électrodes posées sur le scalp dufoetusFetal health must be carefully monitored during pregnancy to detect early fetal cardiac diseases, and provide appropriate treatment. Technological development allows a monitoring during pregnancy using the non-invasive fetal electrocardiogram (ECG). Noninvasive fetal ECG is a method not only to detect fetal heart rate, but also to analyze the morphology of fetal ECG, which is now limited to analysis of the invasive ECG during delivery. However, the noninvasive fetal ECG recorded from the mother's abdomen is contaminated with several noise sources among which the maternal ECG is the most prominent.In the present study, the problem of noninvasive fetal ECG extraction is tackled using multi-modality. Beside ECG signal, this approach benefits from the Phonocardiogram (PCG) signal as another signal modality, which can provide complementary information about the fetal ECG.A general method for quasi-periodic signal analysis and modeling is first described and its application to ECG denoising and fetal ECG extraction is explained. Considering the difficulties caused by the synchronization of the two modalities, the event detection in the quasi-periodic signals is also studied which can be specified to the detection of the R-peaks in the ECG signal.The method considers both clinical and signal processing aspects of the application on ECG and PCG signals. These signals are introduced and their characteristics are explained. Then, using PCG signal as the reference, the Gaussian process modeling is employed to provide the possibility of flexible models as nonlinear estimations. The method also tries to facilitate the practical implementation of the device by using the less possible number of channels and also by using only 1-bit reference signal.The method is tested on synthetic data and also on real data that is recorded to provide a synchronous multi-modal data set.Since a standard agreement for the acquisition of these modalities is not yet taken into much consideration, the factors which influence the signals in recording procedure are introduced and their difficulties and effects are investigated.The results show that the multi-modal approach is efficient in the detection of R-peaks and so in the extraction of fetal heart rate, and it also provides the results about the morphology of fetal ECG
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Beya, 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.
Повний текст джерелаАнотація:
Le coeur est un muscle. Son fonctionnement mécanique est celui d'une pompe chargée de distribuer et de récupérer le sang dans les poumons et dans le système cardiovasculaire. Son fonctionnement électrique est régulé par le son noeud sinusal, un stimulateur ou régulateur électrique chargé de déclencher les battements naturels du coeur qui rythment le fonctionnement du corps. Les médecins surveillent ce fonctionnement électromécanique du coeur en enregistrant un signal électrique appelé électrocardiogramme (ECG) ou un signal sonore : le phono-cardiogramme (PCG). L'analyse et le traitement de ces deux signaux sont fondamentaux pour établir un diagnostic et aider à déceler des anomalies et des pathologies cardiaques. L’objectif de cette thèse est de développer des techniques de traitement des signaux ECG et notamment PCG afin d’aider le médecin dans son analyse de ces signaux. L’idée de fond est de mettre en point des algorithmes relativement simples et peu coûteux en temps de calcul. Le premier intérêt serait de garantir leur implantation aisée dans un système mobile de surveillance cardiaque à l’usage du médecin, voire du patient. Le deuxième intérêt réside dans la possibilité d’une analyse automatique en temps réel des signaux avec le dispositif mobile, autorisant le choix de la transmission de ces signaux pour une levée de doute. De nombreux travaux ont mené à des avancées significatives dans l’analyse des signaux ECG et la reconnaissance automatiques des pathologies cardiaques. Des bases de données de signaux réels ou synthétiques annotées permettent également d’évaluer les performances de toute nouvelle méthode. Quant aux signaux PCG, ils sont nettement moins étudiés, difficiles à analyser et à interpréter. Même si les grandes familles de méthodes (Fourier, Wigner Ville et ondelettes) ont été testées, elles n’autorisent pas une reconnaissance automatique des signatures, d’en avoir une analyse et une compréhension assez fines.La Transformée en Ondelettes (TO) sur les signaux cardiaques a montré son efficacité pour filtrer et localiser les informations utiles mais elle fait intervenir une fonction externe de traitement (ondelette mère) dont le choix dépend de la connaissance au préalable du signal à traiter. Ce n'est pas toujours adapté aux signaux cardiaques. De plus, la Transformée en ondelettes induit généralement une imprécision dans la localisation due à la fonction externe et éventuellement au sous-échantillonnage des signatures. La nature non stationnaire de l'ECG et du PCG et leur sensibilité aux bruits rendent difficile la séparation d’une transition informative d'une transition due aux bruits de mesure. Le choix de l'outil de traitement doit permettre un débruitage et une analyse de ces signaux sans délocalisation des singularités ni altération de leurs caractéristiques. En réponse à nos objectifs et considérant ces différents problèmes, nous proposons de nous appuyer principalement sur la décomposition modale empirique (EMD) ou transformée de Hilbert Huang (THH) pour développer des solutions. L’EMD est une approche non linéaire capable de décomposer le signal étudié en fonctions modales intrinsèques (IMF), oscillations du type FM-AM, donnant ainsi une représentation temps/échelle du signal. Associée à la transformée de Hilbert (TH), la THH permet de déterminer les amplitudes instantanées (AI) et les fréquences instantanées (FI) de chaque mode, menant ainsi à une représentation temps/fréquence des signaux.Sans faire intervenir une fonction externe, on peut ainsi restaurer (réduction de bruit), analyser et reconstruire le signal sans délocalisation de ses singularités. Cette approche permet de localiser les pics R de l'ECG, déterminer le rythme cardiaque et étudier la variabilité fréquentielle cardiaque (VFC), localiser et analyser les composantes des bruits B1 et B2 du PCGThe 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
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Law, E. L. "RF SPECTRAL CHARACTERISTICS OF RANDOM PCM/FM AND PSK SIGNALS." International Foundation for Telemetering, 1991. http://hdl.handle.net/10150/612122.
Повний текст джерелаАнотація:
International Telemetering Conference Proceedings / November 04-07, 1991 / Riviera Hotel and Convention Center, Las Vegas, NevadaThe telemetry radio frequency (RF) spectrum is rapidly becoming more crowded. Therefore, telemetry system engineers and frequency managers must become more knowledgeable about the RF spectral characteristics of telemetry signals. This paper presents methods to calculate the expected RF spectrum of random non-return-to-zero (NRZ) pulse code modulation (PCM)/frequency modulation (FM) and phase shift key (PSK) signals. The discussion includes the effects of bit rate, peak deviation, premodulation filtering, and spectrum analyzer resolution bandwidth. The methods are easily implemented using a personal computer and a spreadsheet program with graphics capability. Calculated spectra agree well with measured spectra. Equations are presented for accurately estimating the peak deviation and unmodulated carrier power of a random NRZ PCM/FM signal from the measured RF spectrum. Adjacent channel interference is also calculated. Key words: radio frequency spectral occupancy, pulse code modulation, frequency modulation, phase shift keying, premodulation filtering, adjacent channel interference.
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Ahlström, Christer. "Nonlinear phonocardiographic Signal Processing." Doctoral thesis, Linköpings universitet, Fysiologisk mätteknik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-11302.
Повний текст джерелаАнотація:
The aim of this thesis work has been to develop signal analysis methods for a computerized cardiac auscultation system, the intelligent stethoscope. In particular, the work focuses on classification and interpretation of features derived from the phonocardiographic (PCG) signal by using advanced signal processing techniques. The PCG signal is traditionally analyzed and characterized by morphological properties in the time domain, by spectral properties in the frequency domain or by nonstationary properties in a joint time-frequency domain. The main contribution of this thesis has been to introduce nonlinear analysis techniques based on dynamical systems theory to extract more information from the PCG signal. Especially, Takens' delay embedding theorem has been used to reconstruct the underlying system's state space based on the measured PCG signal. This processing step provides a geometrical interpretation of the dynamics of the signal, whose structure can be utilized for both system characterization and classification as well as for signal processing tasks such as detection and prediction. In this thesis, the PCG signal's structure in state space has been exploited in several applications. Change detection based on recurrence time statistics was used in combination with nonlinear prediction to remove obscuring heart sounds from lung sound recordings in healthy test subjects. Sample entropy and mutual information were used to assess the severity of aortic stenosis (AS) as well as mitral insufficiency (MI) in dogs. A large number of, partly nonlinear, features was extracted and used for distinguishing innocent murmurs from murmurs caused by AS or MI in patients with probable valve disease. Finally, novel work related to very accurate localization of the first heart sound by means of ECG-gated ensemble averaging was conducted. In general, the presented nonlinear processing techniques have shown considerably improved results in comparison with other PCG based techniques. In modern health care, auscultation has found its main role in primary or in home health care, when deciding if special care and more extensive examinations are required. Making a decision based on auscultation is however difficult, why a simple tool able to screen and assess murmurs would be both time- and cost-saving while relieving many patients from needless anxiety. In the emerging field of telemedicine and home care, an intelligent stethoscope with decision support abilities would be of great value.
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Hákonardóttir, Stefanía. "Prosthetic Control using Implanted Electrode Signals." Thesis, KTH, Skolan för teknik och hälsa (STH), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-147699.
Повний текст джерелаАнотація:
This report presents the design and manufacturing process of a bionic signal messagebroker (BSMB), intended to allow communication between implanted electrodes andprosthetic legs designed by Ossur. The BSMB processes and analyses the data intorelevant information to control the bionic device. The intention is to carry out eventdetection in the BSMB, where events in the muscle signal are matched to the events ofthe gait cycle (toe-o, stance, swing).The whole system is designed to detect muscle contraction via sensors implantedin residual muscles and transmit the signals wireless to a control unit that activatesassociated functions of a prosthetic leg. Two users, one transtibial and one transfemoral,underwent surgery in order to get electrodes implantable into their residual leg muscles.They are among the rst users in the world to get this kind of implanted sensors.A prototype of the BSMB was manufactured. The process took more time thanexpected, mainly due to the fact that it was decided to use a ball grid array (BGA)microprocessor in order to save space. That meant more complicated routing and higherstandards for the manufacturing of the board. The results of the event detection indicatethat the data from the implanted electrodes can be used in order to get sucient controlover prosthetic legs. These are positive ndings for users of prosthetic legs and shouldincrease their security and quality of life.It is important to keep in mind when the results of this report are evaluated that allthe testing carried out were only done on one user each.
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Ilavský, Ľubomír. "Řadič sběrnice PCI pro vývojovou kartu s obvodem FPGA." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2009. http://www.nusl.cz/ntk/nusl-236661.
Повний текст джерелаАнотація:
This thesis deals with the communication on the PCI bus and the design of controllers for the PCI card with FPGA circuit. The introduction shows the functionality and structure of FPGA circuits, followed by description of the principle of communication through the PCI bus. After an analysis of the PCI the thesis describes a design of controllers for a target card and lets the reader get acquainted with its different parts. In the process of implementation carefully examines the structure and operation of individual blocks of PCI controller. In the following part the thesis shows the process of implementation and testing of the final solution using the educational card with FPGA circuit.
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Ahn, Seung Choon. "Variable threshold detection with weighted PCM signal transmitted over Gussian channel." Ohio : Ohio University, 1986. http://www.ohiolink.edu/etd/view.cgi?ohiou1183126123.
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Ahn, Seung Choon. "Variable threshold detection with weighted PCM signal transmitted over Guassian channel." Ohio University / OhioLINK, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1183126123.
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Rose, Robert P., and James L. Rieger. "Transmission of a PCM Telemetry Subcarrier with a Baseband TV Signal." International Foundation for Telemetering, 1991. http://hdl.handle.net/10150/612078.
Повний текст джерелаАнотація:
International Telemetering Conference Proceedings / November 04-07, 1991 / Riviera Hotel and Convention Center, Las Vegas, NevadaAn FM television system using a baseband color TV signal with a 100 kB/s PCM data FM subcarrier is described. Techniques used are based more like those for satellite transmission of TV images than those used for telemetry or broadcast TV. Discussion of optimization of transmission bandwidth, deviation, and subcarrier injection levels are discussed, along with the philosopy and application of such designs in instrumentation systems.
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Powell, David G. "How to Build a High Accuracy, 100 Channel, PCM Encoder for $29.95." International Foundation for Telemetering, 1992. http://hdl.handle.net/10150/611920.
Повний текст джерелаАнотація:
International Telemetering Conference Proceedings / October 26-29, 1992 / Town and Country Hotel and Convention Center, San Diego, CaliforniaPulse Code Modulation (PCM) Encoders are extensively used in instrumentation and telemetry systems. Commercially available encoders are available from several sources and vary in complexity depending on the application. Encoders often include analog signal conditioning, a system clock, and one or more digital input ports. Many of these systems also cost several thousand dollars and the cost goes up when high data accuracy of one or two percent is required. This paper describes a low cost approach which has been used in production telemetry applications with great success and which yields a PCM encoder with data accuracies of better than 2%.
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Gasnárek, Jiří. "Využití bezdrátových technologií k přenosu audio signálu." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219853.
Повний текст джерелаАнотація:
Description of construction of analog-to-digital and digital-to-analog convertors for audio signal and distribution via wireless channel, are the objectives of my master's thesis. There are descriptions of DPS construction, design of panels and measurement of system parameters in the project, above all sampling and reconstruction of audio signal, power consumption and signal range of wireless modules. At the end is discussed real usage and suggestions for further developement.
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Tate, Jeffrey J. "Automating Signal Conditioning Setup Through Integration with Sensor Information." International Foundation for Telemetering, 1997. http://hdl.handle.net/10150/607535.
Повний текст джерелаАнотація:
International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, NevadaCaterpillar Inc. has been testing construction and mining equipment using Computerized Analysis Vans for two decades. During our latest van upgrade, we chose to move to PCM/FM from FM/FM mainly to increase the channel count. We also replaced our old signal conditioning that used span and balance potentiometers with computer programmable signal conditioning. This new signal conditioning requires that the gain and balance point be calculated for every channel on each test. The formulas for these calculations depend on the sensor, the signal conditioning card used, and the test requirements. Due to the number and variety of machines tested at the Caterpillar Proving Grounds, these calculations needed to be automated. Using a few initial parameters and the information from our sensor calibration database, each channel’s balance point, gain, and expected slope are calculated. This system has increased productivity, accuracy, and consistency over manually calculating these parameters. This paper covers the sensor database, the calculated parameters and an overview of the way the system works.
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Gibson, David, N. B. Penrose, Michael Doerr, and Gary Borgen. "HSTSS-DAC CUSTOM INTEGRATED CIRCUITS FOR SUBMINIATURE PCM TELEMETRY AND SIGNAL CONDITIONING." International Foundation for Telemetering, 1999. http://hdl.handle.net/10150/608711.
Повний текст джерелаАнотація:
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, NevadaTo meet specific test and evaluation requirements, the Hardened Subminiature Telemetry and Sensor Systems (HSTSS) program is addressing the miniaturization and ‘G’ hardening of telemetry components. Two custom Integrated Circuits (ICs) are in development to support the design of miniature Pulse Code Modulation (PCM) systems with up to 128 analog input channels. This paper describes the design and development of the custom IC chips of the HSTSS Data Acquisition Chipset (DAC). The original requirements, the roll of the Integrated Product Team (IPT), design decisions, a discussion of the additional features, and practical limitations of the Data Acquisition Chipset will be covered.
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Azizi, Farouk. "Microfluidic Chemical Signal Generation." Cleveland, Ohio : Case Western Reserve University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=case1244664596.
Повний текст джерелаАнотація:
Thesis(Ph.D.)--Case Western Reserve University, 2009Title from PDF (viewed on 2009-11-23) Department of Electrical Engineering Includes abstract Includes bibliographical references and appendices Available online via the OhioLINK ETD Center
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Law, Eugene. "ADJACENT CHANNEL INTERFERENCE MEASUREMENTS WITH CPFSK, CPM AND FQPSK-B SIGNALS." International Foundation for Telemetering, 2002. http://hdl.handle.net/10150/606310.
Повний текст джерелаАнотація:
International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, CaliforniaThis paper will present measured data in an adjacent channel interference (ACI) environment for filtered continuous phase frequency shift keying (CPFSK or FM), multi-h continuous phase modulation (multi-h CPM or CPM for short) [1] and Feher’s patented quadrature phase shift keying (FQPSK-B) [2]. This paper is an extension of my 2001 International Telemetering Conference paper on this topic [3]. The quantity measured was bit error probability (BEP) versus signal energy per bit to noise power spectral density ratio (E(b)/N(o)). The interferers were CPFSK, CPM, or FQPSK-B signals. The results presented in this paper will be for a desired signal bit rate of 5 Mb/s, one interferer 20 dB larger than desired signal (a few tests included two interferers), and various center frequency spacings, interfering signals, receivers, and demodulators. The overall ACI test effort will collect data sets at several bit rates and with one and two interferers. The results will be useful to system designers and range operators as they attempt to maximize the number of Mb/s that can be simultaneously transmitted with minimal interference in the telemetry bands.
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Trover, William F. "Software Control of a High Speed, Modular Signal Conditioner and PCM Encoder System." International Foundation for Telemetering, 1988. http://hdl.handle.net/10150/615249.
Повний текст джерелаАнотація:
International Telemetering Conference Proceedings / October 17-20, 1988 / Riviera Hotel, Las Vegas, NevadaThe increasing channel capacity and complexity of flight test data acquisition systems have made the problems of physical distribution of the system throughout the test aircraft and determining the system configuration a very time consuming and costly portion of the flight test process. These problems are complicated because the new aircraft, irrespective of size, have more complex systems and less space is available to install the classical data acquisition and recording system. The solution to the installation problem is to have a highly modular system that can be configured as either a distributed system with remote multiplexing and a PCM Central Controller, or with the same multiplexed hardware as a stand-alone or master/slave system where the functional power and complexity afforded by the PCM Central Controller are not required. The solution to the configuration control problem is to have a 'hands-off' data acquisition system with all variables of the signal conditioning and PCM encoding functions under software control. In one concept, this includes functions such as instrumentation amplifier gains and offsets, presample filter knee selection, a common gain programmable amplifier with programmable offsets, and randomly addressable multiplexers with a PCM Central Controller that can store multiple data cycle maps. With all of the variable functions of the system under software control, system configuration can be determined automatically during pre- and post-flight test from a portable ground test set that produces a hardcopy printout of the system configuration. This system concept is being augmented by increasing sampling rate capability up to 500k sps for processing vibration/acoustic data. Fiber optical communications are available between the PCM Central Controller and the remote signal conditioners and multiplexers to provide immunity from extremely high common mode plateaus between subsystem elements located in different parts of a composite materials airframe. This next generation data system is being developed for general purpose flight and ground test applications.
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Wang, Jin. "An Incremental Multilinear System for Human Face Learning and Recognition." FIU Digital Commons, 2010. http://digitalcommons.fiu.edu/etd/312.
Повний текст джерелаАнотація:
This dissertation establishes a novel system for human face learning and recognition based on incremental multilinear Principal Component Analysis (PCA). Most of the existing face recognition systems need training data during the learning process. The system as proposed in this dissertation utilizes an unsupervised or weakly supervised learning approach, in which the learning phase requires a minimal amount of training data. It also overcomes the inability of traditional systems to adapt to the testing phase as the decision process for the newly acquired images continues to rely on that same old training data set. Consequently when a new training set is to be used, the traditional approach will require that the entire eigensystem will have to be generated again. However, as a means to speed up this computational process, the proposed method uses the eigensystem generated from the old training set together with the new images to generate more effectively the new eigensystem in a so-called incremental learning process. In the empirical evaluation phase, there are two key factors that are essential in evaluating the performance of the proposed method: (1) recognition accuracy and (2) computational complexity. In order to establish the most suitable algorithm for this research, a comparative analysis of the best performing methods has been carried out first. The results of the comparative analysis advocated for the initial utilization of the multilinear PCA in our research. As for the consideration of the issue of computational complexity for the subspace update procedure, a novel incremental algorithm, which combines the traditional sequential Karhunen-Loeve (SKL) algorithm with the newly developed incremental modified fast PCA algorithm, was established. In order to utilize the multilinear PCA in the incremental process, a new unfolding method was developed to affix the newly added data at the end of the previous data. The results of the incremental process based on these two methods were obtained to bear out these new theoretical improvements. Some object tracking results using video images are also provided as another challenging task to prove the soundness of this incremental multilinear learning method.
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Emlyn-Jones, Daniel. "A gene required for the regulation of photosynthetic light harvesting in the cyanobacterium Synechocystis PCC 6803." Thesis, University College London (University of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322367.
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Anwar, Naveed. "Identification and quantitive analysis of receptor mRNA in the rat pineal gland using competitive RT-PCR." Thesis, King's College London (University of London), 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286316.
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Veeman, Michael Terrence. "Zebrafish prickle : non-canonical Wnt/PCP functions in vertebrate gastrulation /." Thesis, Connect to this title online; UW restricted, 2003. http://hdl.handle.net/1773/4999.
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Patancheru, Govardhan Reddy. "Wearable Heart Rate Measuring Unit." Thesis, Mittuniversitetet, Avdelningen för elektronikkonstruktion, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-23351.
Повний текст джерелаАнотація:
Despite having the numerous evolved heart rate measuring devices and progress in their development over the years, there always remain the challenges of modern signal processing implementation by a comparatively small size wearable device. This thesis paper presents a wearable reflectance photoplethysmography (PPG) sensor system for measuring the heart rate of a user both in steady and moving states. The size and, power consumption of the device are considered while developing, to ensure an easy deployment of the unit at the measuring site and the ability to power the entire unit with a battery .The selection of both the electronic circuits and signal processing techniques is based on their sensitivity to PPG signals, robustness against noise inducing artifacts and miniaturization of the entire measuring unit. The entire signal chain operates in the discrete-time, which allows the entire signal processing to be implemented in firmware on an embedded microprocessor. The PPG sensor system is implemented on a single PCB that consumes around 7.5mW of power. Benchmarking tests with standard heart rate measuring devices reveal that the developed measurement unit (combination of the PPG sensor system, and inertial measurement unit (IMU) developed in-house at Acreo Swedish ICT, and a battery) is comparable to the devices in detecting heart rate even in motion artifacts environment. This thesis work is carried out in Acreo Swedish ICT, Gothenburg, Sweden in collaboration with MidSweden University, Sundsvall, Department of Electronics Design. This report can be used as ground work for future development of wearable heart rate measuring units at Acreo Swedish ICT.
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Peng, Song. "RESTORE PCM TELEMETRY SIGNAL WAVEFORM BY MAKING USE OF MULTI-SAMPLE RATE INTERPOLATION TECHNOLOGY." International Foundation for Telemetering, 1999. http://hdl.handle.net/10150/607318.
Повний текст джерелаАнотація:
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, NevadaThere are two misty understandings about PCM telemetry system in conventional concept: Waveform can not be restored accurately; to be restored accurately, a measured signal must be sampled at a higher sample rate. This paper discusses that by making use of multi-sample rate DSP technology, the sample rate of a measured signal can be reduced in transmission equipment, or system precision can be retained even if the performance of low pass filter declined.
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Law, Eugene. "RECOMMENDED MINIMUM TELEMETRY FREQUENCY SPACING WITH CPFSK, CPM, SOQPSK, AND FQPSK SIGNALS." International Foundation for Telemetering, 2003. http://hdl.handle.net/10150/606726.
Повний текст джерелаАнотація:
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, NevadaThis paper will present equations for calculating the minimum recommended frequency separation of two digital telemetry signals. The signals can be filtered continuous phase frequency shift keying (CPFSK), multi-h continuous phase modulation (CPM) [1], shaped offset quadrature phase shift keying-Telemetry Group (SOQPSK-TG, aka SOQPSK-A*) [2], or Feher’s patented quadrature phase shift keying FQPSK-B (or FQPSK-JR [3]). The equations are based on measured data in an adjacent channel interference (ACI) environment for filtered CPFSK (aka PCM/FM), multi-h CPM (or CPM for short), SOQPSK-TG, FQPSK-JR, and FQPSK-B. This paper is an extension of my 2001 and 2002 International Telemetering Conference papers on this topic [4, 5]. The quantity measured was bit error probability (BEP) versus frequency separation at a given signal energy per bit to noise power spectral density ratio (Eb/No). The interferers were CPFSK, CPM, SOQPSK-TG or FQPSK-B (-JR) signals. The results presented in this paper will be for a desired signal bit rate of 1 to 20 Mb/s, one interferer 20 dB larger than the desired signal (a few tests included two interferers), and various center frequency spacings, interfering signals, receivers, and demodulators. The overall ACI test effort has collected data sets at several bit rates and with one and two interferers. The results will be useful to system designers and range operators as they attempt to maximize the number of Mb/s that can be simultaneously transmitted with minimal interference in the telemetry bands.
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Jang, Kyoung-Jin. "Mitochondrial function provides instructive signals for activation-induced B cell fates." Kyoto University, 2015. http://hdl.handle.net/2433/199208.
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Veverka, Vojtěch. "Automatické rozměření vícesvodových EKG signálů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-316834.
Повний текст джерелаАнотація:
This semester thesis is focused on automated measurement of ECG signal. The theoretical part describes the rise and options ECG signal. Furthermore, the issue is staged principal components analysis, whose output is used as input signal for seasons. They describe the basic methods used in measurement to ECG signal. The practical part is designed in measurement algorithm for ECG signal that has been tested on basic CSE database. The results are discussed in the conclusion.
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Koutsogiannis, Grigorios. "Novel TDE demodulator and kernal-PCA denoising algorithms for improvement of reception of communication signal." Thesis, University of Strathclyde, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401349.
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Ajpru, Supaporn. "Signal transduction gene expression in the melatonin rhythm generating system : quantitative analysis using competitive PCR." Thesis, King's College London (University of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326268.
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Uggla, Lingvall Kristoffer. "Remote heart rate estimation by evaluating measurements from multiple signals." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-210303.
Повний текст джерелаАнотація:
Heart rate can say a lot about a person's health. While most conventional methods for heart rate measurement require contact with the subject, these are not always applicable. In this thesis, a non-invasive method for pulse detection is implemented and analyzed. Different signals from the color of the forehead—including the green channel, the hue channel and different ICA and PCA components—are inspected, and their resulted heart rates are weighted together according to the significance of their FFT peaks. The system is tested on videos with different difficulties regarding the amount of movement and setting of the scene. The results show that the approach of weighting measurements from different signals together has great potential. The system in this thesis, however, does not perform very well on videos with a lot of movement because of motion noise. Though, with better, less noisy signals, good results can be expected.En människas puls säger en hel del om dennes hälsa. För att mäta pulsenanvänds vanligtvis metoder som vidrör människan, vilket iblandär en nackdel. I det här examensarbetet tas en metod för pulsmätningpå avstånd fram, som endast använder klipp från en vanlig videokamera. Färgen i pannan mäts och utifrån den genereras flera signalersom analyseras, vilket resulterar i olika mätvärden för pulsen. Genomatt värdera dessa mätvärden med avseende på hur tydliga signalernaär, beräknas ett viktat medelvärde som ett slutgiltigt estimat på medelpulsen. Metoden testas på videoklipp med varierande svårighetsgrad,beroende på hur mycket rörelser som förekommer och på vilketavstånd från kameran försökspersonen står. Resultaten visar att metodenhar mycket god potential och att man kan man förvänta sig finaresultat med bättre, mindre brusiga signaler.
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Matuszek, Martin. "Měření pulzu z videa." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2014. http://www.nusl.cz/ntk/nusl-236098.
Повний текст джерелаАнотація:
The aim of the Master's thesis was to study contemporary methods for human pulse detection from standard video and suggest a method, which can be used to detect the pulse. Approaches of detecting miniature changes between frames of a video are presented. Position changes of the feature points or changes in colour of some part of an image are detected. It capitalize on the fact that those changes are caused by the pulse of blood. The method for color changes magnification is selected as a base for pulse detector. Face regions of interest are analyzed to detect frequency of changes of intensity between frames. 1D signal is gained and its analysis leads to heart rate. Approach to create heat map of frequency changes is also presented.
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Briju, Betsy J. "Progress of Work towards Cloning Gravity Persistence Signal (gps) Mutants by PCR-Based Methods and Positional Mapping." Ohio University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1320862556.
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Taki, Mohamed. "Identification and simulation of critical interconnect paths with respect to transient noise on PCB-level." Aachen Shaker, 2008. http://d-nb.info/992686016/04.
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Della, Chiesa Enrico. "Implementazione Tensorflow di Algoritmi di Anomaly Detection per la Rilevazione di Intrusioni Mediante Signals of Opportunity (SoOP)." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
Знайти повний текст джерелаАнотація:
In questo elaborato viene presentata l’implementazione di algoritmi di machine learning di tipo supervised e unsupervised attraverso Python e Tensorflow. In particolare viene affrontato come caso di studio l’implementazione di algoritmi di Anomaly Detection. Nel Capitolo 1 vengono presentati gli algoritmi di machine learning implementati. Nel Capitolo 2 viene presentato e analizzato l’ambiente di sviluppo utilizzato, costituito da Python e Tensoflow. Infine è presentata l’implementazione degli algoritmi descritti al capitolo 1. Nel Capitolo 3 sono implementati come caso di studio due algoritmi tratti dall’articolo Anomaly Detection Using WiFi Signals of Opportunity. Il caso di studio prevede la rilevazione di cambiamenti della configurazione spaziale
di una stanza utilizzando i segnali WiFi presenti nell’ambiente ed algoritmi di Anomaly Detection. Gli algoritmi sono stati riprodotti attraverso Python e Tensorflow. Inoltre è presentata un’ulteriore soluzione basata su una rete neurale autoassociativa (autoencoder). Infine sono riportate le conclusioni, in cui viene fatto il resoconto dei risultati ottenuti ed effettuato un accenno a sviluppi futuri.
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Collesei, Marco. "Quality investigation of an ATLAS Phase-II DAQ board via Signal Integrity simulations." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/23188/.
Повний текст джерелаАнотація:
The Large Hadron Collider (LHC) is the most significant expression of the efforts of physicists all over the world and it is always under development to push its colliding and detection limits. As a matter of fact, by the end of 2024 the installation work of a renewed collider, capable of reaching a nominal luminosity of 7.5x10^34 cm-2*s-1, will take place. The new apparatus, called High Luminosity-LHC (HL-LHC), will be operational at least for another decade and, to accomplish the challenges posed by the search for new physics, the main detectors such as A Toroidal LHC ApparuS (ATLAS) and Compact Muon Solenoid (CMS) will be upgraded for Phase-II. Together with the structural changings in ATLAS sub-detectors, the entire Trigger and Data Acquisition (TDAQ) strategy will be upgraded by the implementation of new technologies. Among these technology advancements the FrontEnd LInk eXchange (FELIX) DAQ board, developed by Brookhaven National Laboratory (BNL) together with ATLAS, will play a prominent role. The new high-speed Printed Circuit Board (PCB) will handle the communication between the sub-detectors, the first level of trigger and the Dataflow, thanks to its multi Gb/s links and programmable logic, which makes the board a versatile and long-lasting element of the TDAQ chain. My personal work has been testing some of the transmission channels of FELIX Phase-II board, in the light of Signal Integrity (SI), with the goal to supply simulation results confirming the reliability of its high data-rate lines. Ultimately, I have given evidence that high-speed digital design is a key step in DAQ boards research and development, and it is an essential instrument to reach optimal performances.
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Jang, Jichan. "Caractérisation de deux protéines phosphatases impliquées dans la régulation de la différenciation des hétérocystes chez la cyanobactérie Anabaena sp. PCC 7120." Aix-Marseille 2, 2007. http://theses.univ-amu.fr.lama.univ-amu.fr/2007AIX22013.pdf.
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Johansson, Peter. "Plant Condition Measurement from Spectral Reflectance Data." Thesis, Linköping University, Computer Vision, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-59286.
Повний текст джерелаАнотація:
The thesis presents an investigation of the potential of measuring plant condition from hyperspectral reflectance data. To do this, some linear methods for embedding the high dimensional hyperspectral data and to perform regression to a plant condition space have been compared. A preprocessing step that aims at normalized illumination intensity in the hyperspectral images has been conducted and some different methods for this purpose have also been compared.A large scale experiment has been conducted where tobacco plants have been grown and treated differently with respect to watering and nutrition. The treatment of the plants has served as ground truth for the plant condition. Four sets of plants have been grown one week apart and the plants have been measured at different ages up to the age of about five weeks. The thesis concludes that there is a relationship between plant treatment and their leaves' spectral reflectance, but the treatment has to be somewhat extreme for enabling a useful treatment approximation from the spectrum. CCA has been the proposed method for calculation of the hyperspectral basis that is used to embed the hyperspectral data to the plant condition (treatment) space. A preprocessing method that uses a weighted normalization of the spectrums for illumination intensity normalization is concluded to be the most powerful of the compared methods.
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Frejd, Andreas. "Analysis and verification of routing effects on signal integrity for high-speed digital stripline interconnects in multi-layer PCB designs." Thesis, Linköpings universitet, Institutionen för systemteknik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-76899.
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The way printed circuit board interconnects for high-speed digital signals are designed ultimately determines the performance that can be achieved for a certain interface, thus having a profound impact on whether the complete communication channel will comply with the desired standard specification or not. Good understanding and methods for anticipating and verifying this behaviour through computer simulations and practical measurements are therefore essential. Characterization of an interconnect can be performed either in the time domain or in the frequency domain. Regardless of the domain chosen, a method for unobstrusively connecting to the test object is required. After various different attempts it could be concluded that frequency domain measurements using a vector network analyzer together with microwave probes will provide the best measurement fidelity and ease of use. In turn, this method requires the test object to be prepared for the measurement. Advanced computer simulation software is available, but comes with the drawback of dramatically increasing the requirements on computational resources for improved accuracy. In general, these simulators can be configured to show good agreement with measurements at frequencies as high as ten gigahertz. For ideal interconnects, the simplest and, thus, fastest methods will provide good enough accuracy. These simple methods should be complemented with the results from more accurate simulations in cases where the physical structure is complex or in other ways deviates from the ideal. Several practical routing situations were found to introduce severe signal integrity issues. Through appropriate use of the methods developed in this thesis, these can be identified in the design process and thereby avoided.
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PENHARLOW, DAVID. "MICROMINIATURE DISTRIBUTED DATA ACQUISITION SYSTEM." International Foundation for Telemetering, 1990. http://hdl.handle.net/10150/613485.
Повний текст джерелаАнотація:
International Telemetering Conference Proceedings / October 29-November 02, 1990 / Riviera Hotel and Convention Center, Las Vegas, NevadaThe new generation of advanced tactical aircraft and missiles places unique demands on the electronic and mechanical designs for flight test instrumentation, high bit rates, operating temperature range and system interconnect wiring requirements. This paper describes a microminiature PCM distributed data acquisition system with integral signal conditioning (MMSC) which has been used in advanced aircraft and missile flight testing. The MMSC system is constructed from microminiature, stackable modules which allow the user to reconfigure the system as the requirements change. A second system is also described which uses the same circuitry in hermetic hybrid packages on plug-in circuit boards.
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Beneš, Radek. "Využití metod zpracování signálů pro zvýšení bezpečnosti automobilové dopravy." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-218105.
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This diploma thesis deals with the issue of the recognition of road signs in the video sequence. Such systems increase the traffic safety and are implemented by major car factories in the manufactured cars (Opel, BMW). First, the motivation for the utilisation of these systems is presented, followed by the survey of the current state of the art methods. Finally, a specific road-sign detection method is chosen and described in detail. The method uses advanced techniques of signal processing. Segmentation method in color space is used for sign detection and subsequent classification is accomplished by linear classification with optional use of PCA method. In addition, the method contains the prediction of road sign positions based on Kalman filtering. Implemented system yields relatively accurate results and overall analysis and discussion is enclosed.
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Vařečka, Martin. "Stanovení krevního tlaku pomocí chytrého telefonu." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2018. http://www.nusl.cz/ntk/nusl-378143.
Повний текст джерелаАнотація:
Blood pressure is one of the basic indicators of the health state of the cardiovascular system. High blood pressure is the main risk factor of ischemic heart disease, atherosclerosis and stroke. Therefore, it is important to monitor long-term changes in blood pressure and respond in time to these changes. Blood pressure meters are not standard household equipment, while a well-equipped smartphone is. Smartphones contain a large number of sensors capable of measuring biomedical signals. This thesis focuses on creating an application capable of determining blood pressure using data obtained from these sensors.
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Cao, Yanyan. "Anti-diabetic and anti-cancer activities of penta-O-galloyl-alpha-D-glucopyranose (alpha-PGG) and its derivative 6-chloro-6-deoxy-1,2,3,4-tetra-O-galloyl-alpha-D-glucopyranose (6CI-TGO)." Ohio : Ohio University, 2009. http://www.ohiolink.edu/etd/view.cgi?ohiou1257458049.
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Watzer, Björn Verfasser], and Karl [Akademischer Betreuer] [Forchhammer. "Regulation of the carbon/nitrogen storage polymer cyanophycin by the signal transduction protein PII in Synechocystis sp. PCC 6803 / Björn Watzer ; Betreuer: Karl Forchhammer." Tübingen : Universitätsbibliothek Tübingen, 2019. http://d-nb.info/1187724629/34.
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Laurent, Sophie. "Développement des hétérocystes chez la cyanobactérie Anabaena PCC 7120 : Identification du signal initiateur de la différenciation. Rôle de PII dans le métabolisme des hétérocytes." Aix-Marseille 2, 2005. http://www.theses.fr/2005AIX22059.
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Watzer, Björn [Verfasser], and Karl [Akademischer Betreuer] Forchhammer. "Regulation of the carbon/nitrogen storage polymer cyanophycin by the signal transduction protein PII in Synechocystis sp. PCC 6803 / Björn Watzer ; Betreuer: Karl Forchhammer." Tübingen : Universitätsbibliothek Tübingen, 2019. http://d-nb.info/1187724629/34.
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Asar, Sita Madhu. "An Audio Processing System as an Example of Modern Circuit Board Design." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1480588012253634.
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Gaut, Ludovic. "Mechanical and molecular signals underlying tendon cell differentiation." Electronic Thesis or Diss., Sorbonne université, 2018. http://www.theses.fr/2018SORUS301.
Повний текст джерелаАнотація:
Les tendons sont une forme unique de tissu conjonctif au sein du système musculosquelettique. Le développement, l’homéostasie et la réparation du tendon reposent sur des combinaisons de paramètres moléculaires et aussi mécaniques, régulant la production et l’assemblage des fibres de collagène. Notre objectif est de comprendre quelles sont les voies de mécanotransduction impliquées dans la différentiation tendineuse, via deux (co-)facteurs de transcription : EGR1 et YAP. Nous avons montré que l’expression du gène de tendon SCX, de EGR1 et l'activité de YAP sont réduites dans les tendons de membres de fœtus de poulet immobilisés. De plus, la reprise des contractions musculaires entraîne une reprise de l’expression des gènes de tendon comparable à celle des fœtus jamais immobilisés. La mécanobiologie du tendon a été étudiée avec des constructions cellulaires en 3-dimensions (3D) en gel de fibrine ou de collagène, faits de cellules souches mésenchymateuses. La perte de tension de ces constructions a induit une chute de l’expression de Egr1, des gènes de tendon et de l’activité de YAP. Une surexpression de Egr1 dans les constructions 3D en gel de fibrine sans tension a empêché la chute d’expression des gènes de tendon. L’activité de YAP et l’expression de Scx ont augmenté en étirant les constructions en gel de collagène. L’inactivation de l’activité de YAP par traitement à la verteporfin (VTPF) a induit une diminution de l’expression des gènes de tendon, qui n’a pas été restaurée lorsque ces constructions traitées ont été étirées. Ensemble, ces résultats montrent l’importance de YAP et EGR1 en aval des signaux mécaniques pour réguler la différentiation des cellules du tendonTendons are unique forms of connective tissue of the musculoskeletal system. Tendon development, homeostasis and repair rely on specific combinations of mechanical and molecular factors regulating the production and assembly of collagen fibers. Our objective is to decipher the mechanotransduction pathways underlying tendon cell differentiation, through the activity of two transcription (co-)factors, EGR1 and YAP. We showed that the expression of the tendon gene SCX, the mechanosensitive gene EGR1 and YAP activity were downregulated in limb tendons of immobilized chicken fetuses. Restored muscle contraction after immobilization led to a recovery of tendon gene expression. Tendon mechanobiology was studied in vitro in fibrin- or collagen-based 3-dimensional (3D) constructs made of mesenchymal stem cells and mimicking tendon formation. Tension release in fibrin and collagen 3D-constructs induced a drop of the expression of Egr1, tendon genes and YAP activity. Overexpression of Egr1 was able to prevent the downregulation of tendon gene expression in de-tensioned fibrin 3D-constructs. YAP activity was upregulated in dynamically stretched collagen 3D-constructs and was paired with the expression of the tendon gene Scx. Chemical knock-down of YAP activity with Verteporfin (VTPF) treatment showed a decrease in the expression of YAP target genes and the tendon genes. Besides, dynamic stretch applied on VTPF-treated constructs did not restore tendon gene expression, conforting the role of YAP as an intracellular relay of mechanical cues in tendon cells. Altogether, these results highlight the importance of EGR1 and YAP downstream of mechanical forces during tendon cell differentiation