Wyniki wyszukiwania - BazTech

1

Automatic cardiac arrhythmia classification based on hybrid 1-D CNN and Bi-LSTM model

Rahul Jagdeep, Sharma Lakhan Dev

Biocybernetics and Biomedical Engineering

|

2022

|

Vol. 42, no. 1

312--324

EN

Cardiovascular diseases (CVDs) are a group of heart and blood vessel ailments that can cause chest pain and trouble breathing, especially while active. However, some patients with heart disease have no symptoms and may benefit from screening. Electrocardiogram (ECG) measures electrical activity of the heart using sensors positioned on the skin over the chest, and it can be used for the timely detection of CVDs. This work presents a technique for classification among lethal CVDs like atrial fibrillation (Afib), ventricular fibrillation (Vfib), ventricular tachycardia (Vtec), and normal (N) beats. A novel combination of Stationary wavelet transforms (SWT) and a two-stage median filter with Savitzky–Golay (SG) filter were utilised for pre-processing of the ECG signal followed by segmentation and z-score normalisation process. Next, 1-D six-layers convolutional neural network (1- D CNN) was used for automated and reliable feature extraction. After that, bidirectional long short-term memory (Bi-LSTM) was used in the back end for classification of arrhythmias. The novelty of the present work is the use of 1-D CNN and Bi-LSTM architecture followed by relevant and effective pre-processing of the ECG signal makes this technique accurate and reliable. An accuracy of 99.41 % was achieved using 10-fold cross validation, which is superior to the existing state-of-art methods. Thus, this method presents a noble, accurate, and reliable method for classification of cardiac arrhythmia beats.

2

Parametric analysis for the design of a 4 pole radial permanent magnet generator for small wind turbines

Quintal-Palomo R., Dybkowski M., Gwoździewicz M.

Power Electronics and Drives

|

2016

|

Vol. 1 (36), No. 2

175--186

EN

A review of the literature gives several guidelines for the design of a Permanent Magnet Synchronous Generator (PMSG) for Small Wind Turbines (SWT) applications. This paper presents Finite Element Analysis (FEA) of a Surface Mounted PMSG. Several optimization tests are run in order to yield the lowest Total Harmonic Distortion (THD) and cogging torque with the highest induced voltage. The results of the optimization tests are then utilized to design an initial “optimized” circumferential Internal PMSG. This optimized design is then compared to a non-optimized design, as well as the results of the Surface Mounted PMSG.

3

Wieże z betonu wirowanego pod małe turbozespoły wiatrowe

Łodo A., Michałek J.

Materiały Budowlane

|

2014

|

nr 6

50--51

PL

W pracy podano ogólne zasady obliczeń i doboru konstrukcji wsporczych małych turbin wiatrowych (SWT). Przedstawiono możliwości wykorzystania wirowanych żerdzi strunobetonowych jako konstrukcji wsporczych SWT.

EN

In the paper the general rules of calculations and selection of supporting structures of small wind turbines were given. The possibilities of application of spun pre-tensioned prestressed concrete poles as supporting structures of small wind turbines were presented.