Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: discrete signal processing

Sortuj według:

Ogranicz wyniki do:

End-to end decision support system for sleep apnea detection and Apnea-Hypopnea Index calculation using hybrid feature vector and Machine learning

Arslan Recep Sinan, Ulutas Hasan, Köksal Ahmet Sertol, Bakir Mehmet, Çiftçi Bülent

Biocybernetics and Biomedical Engineering

2023

Vol. 43, no. 4

684--699

Sleep apnea is a disease that occurs due to the decrease in oxygen saturation in the blood and directly affects people’s lives. Detection of sleep apnea is crucial for assessing sleep quality. It is also an important parameter in the diagnosis of various other diseases (diabetes, chronic kidney disease, depression, and cardiological diseases). Recent studies show that detection of sleep apnea can be done via signal processing, especially EEG and ECG signals. However, the detection accuracy needs to be improved. In this paper, a ML model is used for the detection of sleep apnea using 19 static sensor data and 2 dynamic data (Sleep score and Arousal). The sensor data is recorded as a discrete signal and the sleep process is divided into 4.8 M segments. In this work, 19 different sensor data sets were recorded with polysomnography (PSG). These data sets have been used to perform sleep scoring. Then, arousal status marking is done. Model training was carried out with the feature vector consisting of 21 data obtained. Tests were performed with eight different machine learning techniques on a unique dataset consisting of 113 patients. After all, it was automatically determined whether people were diseased (a kind of apnea) or healthy. The proposed model had an average accuracy of 97.27%, while the recall, precision, and f-score values were 99.18%, 95.32%, and 97.20%, respectively. After all, the model that less feature engineering, less complex classification model, higher dataset usage, and higher classification performance has been revealed.

Opis widmowy układów SC i SI przy wykorzystaniu uogólnionych funkcji interpolujących

Kulisz J., Garlicki M.

Elektronika : konstrukcje, technologie, zastosowania

2005

Vol. 46, nr 8

16-20

Przedstawiono wyniki badań, których celem było zaproponowanie pewnego uogólnienia opisu widmowego układów SC i SI. Zmodyfikowana metoda bazuje na opisie dokonywanym w dziedzinie sygnałów dyskretnych. Najistotniejszą jej nowością jest uogólnienie związku pomiędzy opisem w dziedzinie sygnałów ciągłych. Do wyrażenia tego związku wykorzystano bardziej elastyczne pojęcie funkcji interpolującej (ang. sampling function). Uzyskano dzięki temu możliwość aproksymowania sygnałów generowanych w układach SC i SI przebiegami o bardziej realistycznych kształtach, niż stosowania do tej pory funkcja schodkowa.

The paper presents results of research, the objective of which was to propose certain generalisation of SC and SI circuit spectral description. The modified methods is based on description in the discrete time domain. The most essential novelty of the proposed method is generalisation of relation between description in the discrete- and continuous-time domains. A more flexible concept of sampling function was utilised to express the relation.Thanks to this a possibility of approximating signals generated in SC and SI circuits with more realistic waveforms was gained, than the staircase function used so far. As a result, better accuracy of spectrum calculation was obtained.