Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 16 of 16 for “"R wave"”.
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Detection Of The R-wave In Ecg Signals
… aims at providing a new approach for detecting R-waves in the ECG signal and generating the corresponding R-wave impulses with the delay between the original R-waves and the R-wave impulses being lesser than 100 ms. The algorithm was implemented in Matlab and tested with good results against 90 …
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ΟΙ ΜΕΤΑΒΟΛΕΣ ΤΟΥ ΔΥΝΑΜΙΚΟΥ ΤΟΥ ΕΠΑΡΜΑΤΟΣ R ΣΤΟ ΗΛΕΚΤΡΟΚΑΡΔΙΟΓΡΑΦΗΜΑ ΣΑΝ ΔΕΙΚΤΗΣ ΛΕΙΤΟΥΡΓΙΚΟΤΗΤΑΣ ΤΗΣ ΑΡΙΣΤΕΡΗΣ ΚΟΙΛΙΑΣ (ΜΕΛΕΤΗ ΣΕ ΣΥΓΓΕΝΕΙΣ ΚΑΡΔΙΟΠΑΘΕΙΕΣ, ΒΑΛΒΙΔΙΚΕΣ ΠΑΘΗΣΕΙΣ ΚΑΙ ΣΤΕΦΑΝΙΑΙΑ ΝΟΣΟ)
TO EVALUATE R WAVE AMPLITUDE CHANGES IN SYMPTOMATIC TACHYCARDIA 49 PATIENTS WHO UNDERWENT CARDIAC CATHETERIZATION AND ATRIAL PACING WERE STUDIED. THE FINDINGS WERE: 1) THE INCREASE OR DECREASE OF THE AMPLITUDE OF THE R WAVE DURING TACHYCARDIA OR FOLLOWING ATRIAL PACING IS AN INDEX OF BAD OR GOOD …
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Acoustoelastic effects of surface waves in concrete subjected to compressive and bending stresses
… of acoustoelastic effects on Rayleigh surface waves (R-waves) in concrete samples subjected to 4-point load bending and uniaxial compression, considering a broad range of strain levels. The main objectives are (1) to study individually the acoustoelastic effects in tension and compression, …
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Derivation of the respiratory rate signal from a single lead ECG
… signal and produce a usable respiration rate waveform. Three methods for deriving respiration from a single lead ECG were identified and implemented in LabVIEW. The three methods were R wave amplitude modulation (RWA), R wave duration (RWD), and the multiplication of RWA and RWD signals. Data …
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Recognition of Severe Congestive Heart Failure using Parallel Cascade Identification
… this thesis, PCI is applied to distinguish R-R wave intervals of CHF patients who died from those of patients who survived in a 5-year study. The detection accuracy of the PCI detector is evaluated over a first set of 49 patients, and then over a larger set of a further 352 patients, and …
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Control and monitoring of an intra-aortic balloon pump for cardiac assist
… the detector to the spectrum within which the R-wave of an ECG signal lies. A safety circuit to prevent the heart pumping against an inflated balloon is incorporated. History of the 8 secs preceding any instant is available. A description of the medical tests carried out so far is given.
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The Effect of Preload Reduction on Parameters to Evaluate Left Ventricular Diastolic Function
BACKGROUND AND OBJECTIVES: The pulsed wave Doppler echocardiography in the mitral inflow is known to be affected by several factors, such as the loading condition. The mitral annulus velocity and early diastolic flow propagation velocity(Vp) are known to be relatively load independent. Recently, …
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Effects of cardiac gating on fMRI of the human auditory system
… with the Sp02 signal vs. gating with the R-wave of the electrocardiogram (ECG). fMRI activation was routinely detected at all levels of the auditory pathway from the cochlear nucleus to the auditory cortex. Compared to ungated acquisitions, cardiac gating with the SpO2 reduced image signal …
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Wearable Heart Sound and EKG Recorder
… measure changes in the intervals between the R-wave and S1 and S2 heart sounds, and to detect evolving S3 and S4 heart sounds consistent with volume overload. The amplitudes of S1 and S3 heart sounds change as heart failure patients' symptoms worsen. Designing a non-invasive, external device, …
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Automatic detection of qt and related intervals
… of the algorithm for the detection of the Q wave, Tmax afld the Tend to measure the intervals such as QT, QT corrected (QTc), RT, QT_{max} and RT_{max} respectively. The second section deals with the analysis of different variabilities including heart rate variability (HRV), QT, QTc, RT, …
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A wearable heart monitor at the ear using ballistocardiogram (BCG) and electrocardiogram (ECG) with a nanowatt ECG heartbeat detection circuit
… accelerometer. The head BCG's principal peaks (J-waves) are synchronized to heartbeats. Ensemble averaging is used to obtain consistent J-wave amplitudes, which are related to stroke volume. The ECG is sensed locally near the ear using a single-lead configuration. When the BCG and the ECG are used …
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Heart Rate Variability analysis in patients undergoing local anesthesia
… anaesthesia. Signal processing techniques for R-wave detection, signal representation, ectopic beat detection and detrending were first developed and validated with the help of simulated signals and physiological signals from Physionet data base. After the validation stage these methods were then …
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DOMAIN KNOWLEDGE-GUIDED LEARNING FOR ROBUST MYOCARDIAL INFARCTION DETECTION FROM 12-LEAD ELECTROCARDIOGRAMS
… ECG components, such as ST-segment, Q and R wave amplitudes, and Q wave durations; and ii) reconstructing a latent space from a set of differentiable approximations of clinical rules. The methods, i.e., DK-DL, B-DL and RBA were developed on PTB-XL+ dataset. In addition, their performance were …
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The Direct Impact of Trimethelamine-N-Oxide on Cardiac Function
… The electrocardiography (ECG) showed decreased R wave aptitude in 6w and 13w TMAO feed group with sinus rhythm. However, 3w TMAO intake had no impact on both cardiac contractability and ECG. Moreover, chronic TMAO supplement (13w) showed increased left ventricle (LV) mass on echocardiography and …
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Návrh kardiostimulátor typu On Demand v LabVIEW
Návrh kardiostimulátoru typu On Demand pro výukové účely je navržen a realizován v programovém prostředí LabVIEW. Obsahem práce je obecný popis kardiostimulátorů s rozdělením dle různých kritérií zahrnujících způsob a dobu stimulace, rozsah působnosti apod. Konkrétně je řešen typ stimulátoru On …
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Observations of ocean fluctuations between 15 and 23 hour periods in the Pacific
… further shown that resonant barotropic gravity wave modes (Platzman et al., 1981) are not consistent with the data. The cause of these flu ctuations remains unresolved, but the data and other oceanographic measurements put many constraints on the process causing these fluctuations.