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The purpose of this paper is to introduce an accurate algorithm to detect respiration rate and heart beat using an Ultra-Wideband (UWB) signal. One important issue to consider for obtaining precise results is the right selection of measurement parameters in UWB system. In this work the impact of these parameters in detecting respiration rate and heart beat are studied and the best values are suggested...
UWB signals have become attractive for their particular advantage of having narrow pulse width which makes them suitable for remote sensing of vital signals. In this paper a novel approach to estimate periodic motion rates, using ultra wide band (UWB) signals is proposed. The proposed algorithm which is based on wavelet transform is used as a non-contact tool for measurement of respiration motion...
Ultra-Wide Band (UWB) signals have become attractive for their particular advantage of having narrow pulse width which makes them suitable for remote sensing of vital signals. In this work, a MATLAB framework is presented which simulates an environment whereby the UWB signals can be observed and evaluated at different locations of the simulated channel for wireless measurement of heart rate. Main...
The streak artifacts caused by dental fillings are known to generate artifacts in attenuation maps thus leading to overestimation/underestimation of tracer uptake in resulting PET images. Correction of these artifacts is therefore mandatory to achieve accurate attenuation maps to be used by the CT-based attenuation correction procedure. Our group recently proposed a metal artifact reduction method...
Ultra-wideband (UWB) technology provides a convenient approach for remote biomedical sensing and vital signs monitoring in humans. In this paper, a specific algorithm is proposed to improve the ability of heart rate (HR) detection. Unlike previous methods for remote HR detection, the proposed method provides an adaptive filter based on respiration and heart rate parameters obtained from UWB waveforms...
The polyenergetic X-ray spectra used during CT imaging makes it subject to beam hardening artefacts caused by the absorption of low energy X-rays as they pass through the patient. The direct consequence is that the linear attenuation coefficient calculated for thick body regions is lower than in thin regions. This effect generates cupping and streak artefacts in the reconstructed CT images thus compromising...
The presence of high density materials in CT imaging is known to generate strong streak artifacts in CT images. This will obviously impact the generated mumaps, and as such could affect the reconstructed PET image during the CT-based attenuation correction (CTAC) procedure. Thus the attenuation maps (mumaps) generated from these images will likely propagate the artifacts to the resulting PET images...
Since myocardial motion is directly related to cardiac vascular supply, it can be helpful in diagnosing the heart abnormalities. The most comprehensive and available imaging study of the cardiac function is echocardiography and therefore it is important to make the echocardiography motion more quantitative. To overcome the sensitivity to shear, rotation and wide range of motion, we propose an adaptive...
Segmentation of the human airway tree from volumetric computed tomography images is an important stage for many clinical applications such as virtual bronchoscopy. The main challenges of previously developed methods are to deal with two problems namely, leaking into the surrounding lung parenchyma during segmentation and the need to manually adjust the parameters. To overcome these problems, a multi-...
The aim of this work is to provide a quantitative approach to the problem of matching a mother wavelet to Transient Evoked Otoacoustic Emission (TEOAE) signals by using tuning. A tuning curve was used as a template for designing a mother wavelet that has the maximum matching to the tuning curve. The scaling function was calculated from the matched mother wavelet and by using these functions, lowpass...
The performance of ICA algorithms in correct separation of independent sources can be highly affected by existence of noises in the observation data. In this paper a hybrid Wavelet-ICA method for improving the functionality of noise free ICA algorithms in noisy environment is proposed. At first the robustness of two most frequent ICA algorithms, named Fast ICA and Information maximization ICA, for...
One of the most important stages of virtual colonoscopy is colon segmentation, since an incorrect segmentation may lead to a misdiagnosis. Geometric deformable models (GDM) are found as efficient and attractive tools for structural based segmentation in particular to extract objects with complicated topology. There are two parameters influencing the overall performance of GDM algorithm; the distance...
Oral contrast is usually administered in most X-ray computed tomography (CT) examinations of the abdomen and the pelvis as it allows more accurate identification of the bowel and facilitates the interpretation of abdominal and pelvic CT studies. However, the misclassification of contrast medium with high density bone in CT-based attenuation correction (CTAC) is known to generate artifacts in the attenuation...
White matter fibre tractography is a non-invasive method for reconstructing three dimensional trajectories of fibre pathways. Fast Marching is one of fibre tracking methods in which co-linearity of principal eigenvectors determines the speed of front's evolution. In this algorithm effect of tensor's eigenvalues are not considered. In the current work, the speed function of standard fast marching was...
This paper presents the results of morphological heart arrhythmia detection based on parameters which are obtained from modeling of the cumulants of the electrocardiography, ECG signals. Cumulants possess many properties that make them effective tools to describe morphological variations of non-stationary signals. Among these properties, the two most attractive founded for analysis of ECG arrhythmia...
In this paper, a new piecewise modeling for approximation of ECG signal is presented. Most of the modeling methods are focused to obtain the best approximation of the entire ECG signal. The proposed method exploits the importance of different intervals of ECG signals, in particular QRS complex, by performing a segmented based modeling using Hermitian basis functions. This yields to weighting the approximation...
In this paper, a segmentation method for detection of masses in digitized mammograms has been developed using two parallel approaches: adaptive thresholding method and fuzzy entropy feature as a CAD scheme. The algorithm consists of the following steps: a) Preprocessing of the digitized mammograms including identification of region of interest (ROI) as candidate for massive lesion through breast region...
Diagnostic quality medical images consume vast amounts of network time, system bandwidth and disk storage in current computer architectures. There are many ways in which the use of system and network resources may be optimised without compromising quality of diagnostic image. One of these is in the choice of image representation, both for storage and transfer. In this paper, we show how a particularly...
An electrocardiogram (ECG) arrhythmia detection system has been developed. Piecewise continuous trapezoidal fuzzy membership functions and defuzzification schemes have been designed to be used in a fuzzy classifier. Fourteen types of arrhythmias and abnormalities can be detected implementing the classifier. We have evaluated the algorithm on MIT-BIH database. The classifier achieved a sensitivity...
This paper presents the results of morphological heart arrhythmia detection based on features of electrocardiography, ECG, signal. These signals are obtained from MIT/BIH arrhythmia database. The ECG beats were first modeled using Hermitian basis functions, (HBF). In this step, the width parameter, ??, of HBF was optimized to minimize the model error. Then, the feature vector which consists of the...
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