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86 Results Found

  • Article
  • Open Access
684 Views
29 Pages

11 June 2025

In the present paper we study a class of Toeplitz operators called concentration operators that are self-adjoint and compact in the linear canonical Dunkl setting. We show that a finite vector space spanned by the first eigenfunctions of such operato...

  • Article
  • Open Access
758 Views
23 Pages

16 November 2025

This paper presents a novel pipeline leak diagnosis framework that combines Savitzky–Golay scalograms with a lightweight advanced deep learning architecture. Pipelines are critical for transporting fluids and gases, but leaks can lead to operat...

  • Article
  • Open Access
9 Citations
3,107 Views
26 Pages

22 December 2022

Features extracted from the wavelet transform coefficient matrix are widely used in the design of machine learning models to classify event-related potential (ERP) and electroencephalography (EEG) signals in a wide range of brain activity research an...

  • Feature Paper
  • Article
  • Open Access
2,710 Views
35 Pages

25 November 2025

Financial market volatility prediction remains challenging due to data nonlinearity and non-stationarity. Existing quantitative approaches struggle to capture multi-scale information embedded in time series, while convolutional neural network (CNN)-b...

  • Article
  • Open Access
2,293 Views
18 Pages

11 May 2023

Two convolution neural network (CNN) models are introduced to accurately classify event-related potentials (ERPs) by fusing frequency, time, and spatial domain information acquired from the continuous wavelet transform (CWT) of the ERPs recorded from...

  • Article
  • Open Access
1 Citations
2,186 Views
22 Pages

7 February 2022

Nowadays, fault diagnostics is widely applied under Industry 4.0 to reduce machine maintenance costs, improve productivity, and increase machine availability. However, fault diagnostics are mostly post-mortem. When the fault is identified, it is alre...

  • Article
  • Open Access
11 Citations
2,934 Views
15 Pages

5 January 2024

In this study, carbon steel was examined under different corrosive conditions using electrochemical noise (EN) as the primary method of investigation. The corroded carbon steel surfaces were examined using 3D profilometry to gather information about...

  • Article
  • Open Access
6 Citations
3,325 Views
28 Pages

17 December 2024

The automatic detection of arrhythmia is of primary importance due to the huge number of victims caused worldwide by cardiovascular diseases. To this aim, several deep learning approaches have been recently proposed to automatically classify heartbea...

  • Article
  • Open Access
9 Citations
6,029 Views
16 Pages

A procedure aimed at forecasting the velocity trend of a landslide for a period of some hours to one or two days is proposed here together with its MATLAB implementation. The method is based on continuous wavelet transform (CWT) and convolutional neu...

  • Article
  • Open Access
3 Citations
3,106 Views
11 Pages

Utilization of Unsupervised Machine Learning for Detection of Duct Voids inside PSC Box Girder Bridges

  • Da-In Lee,
  • Hyung Choi,
  • Jong-Dae Kim,
  • Chan-Young Park and
  • Yu-Seop Kim

25 January 2022

The PSC box girder bridge is a pre-stressed box girder bridge that accounts for a considerable part of large-scale bridges. However, when concrete is poured, even small mistakes might result in voids that appear during long-term maintenance. In this...

  • Article
  • Open Access
980 Views
32 Pages

AI-Driven Resilient Fault Diagnosis of Bearings in Rotating Machinery

  • Syed Muhammad Wasi ul Hassan Naqvi,
  • Arsalan Arif,
  • Asif Khan,
  • Fazail Bangash,
  • Ghulam Jawad Sirewal and
  • Bin Huang

20 November 2025

Predictive maintenance is increasingly important in rotating machinery to prevent unexpected failures, reduce downtime, and improve operational efficiency. This study compares the efficacy of traditional machine learning (ML) and deep learning (DL) t...

  • Article
  • Open Access
27 Citations
8,865 Views
20 Pages

17 March 2023

This study presents an ear-mounted photoplethysmography (PPG) system that is designed to detect mental stress. Mental stress is a prevalent condition that can negatively impact an individual’s health and well-being. Early detection and treatmen...

  • Article
  • Open Access
9 Citations
5,855 Views
17 Pages

A Scalogram-Based CNN Approach for Audio Classification in Construction Sites

  • Michele Scarpiniti,
  • Raffaele Parisi and
  • Yong-Cheol Lee

21 December 2023

The automatic monitoring of activities in construction sites through the proper use of acoustic signals is a recent field of research that is currently in continuous evolution. In particular, the use of techniques based on Convolutional Neural Networ...

  • Article
  • Open Access
184 Citations
13,195 Views
16 Pages

The studies implemented with Electroencephalogram (EEG) signals are progressing very rapidly and brain computer interfaces (BCI) and disease determinations are carried out at certain success rates thanks to new methods developed in this field. The ef...

  • Article
  • Open Access
7 Citations
2,957 Views
19 Pages

22 June 2023

The continuous advancements in healthcare technology have empowered the discovery, diagnosis, and prediction of diseases, revolutionizing the field. Artificial intelligence (AI) is expected to play a pivotal role in achieving the goals of precision m...

  • Article
  • Open Access
13 Citations
4,938 Views
26 Pages

A Robust Deep Feature Extraction Method for Human Activity Recognition Using a Wavelet Based Spectral Visualisation Technique

  • Nadeem Ahmed,
  • Md Obaydullah Al Numan,
  • Raihan Kabir,
  • Md Rashedul Islam and
  • Yutaka Watanobe

4 July 2024

Human Activity Recognition (HAR), alongside Ambient Assisted Living (AAL), are integral components of smart homes, sports, surveillance, and investigation activities. To recognize daily activities, researchers are focusing on lightweight, cost-effect...

  • Article
  • Open Access
18 Citations
4,756 Views
19 Pages

Fault Detection on Power Transmission Line Based on Wavelet Transform and Scalogram Image Analysis

  • Ahmed Sabri Altaie,
  • Ammar Abbas Majeed,
  • Mohamed Abderrahim and
  • Afaneen Alkhazraji

4 December 2023

Given the massive increase in demand for electrical energy, particularly owing to global climate change and population expansion, as well as the development of complicated electrical systems due to the urgent need for a sophisticated component to enh...

  • Article
  • Open Access
18 Citations
3,376 Views
13 Pages

14 September 2021

The main objective of this study is to propose relatively simple techniques for the automatic diagnosis of electrocardiogram (ECG) signals based on a classical rule-based method and a convolutional deep learning architecture. The validation task was...

  • Article
  • Open Access
29 Citations
4,243 Views
18 Pages

Centrifugal Pump Fault Diagnosis Based on a Novel SobelEdge Scalogram and CNN

  • Wasim Zaman,
  • Zahoor Ahmad,
  • Muhammad Farooq Siddique,
  • Niamat Ullah and
  • Jong-Myon Kim

1 June 2023

This paper presents a novel framework for classifying ongoing conditions in centrifugal pumps based on signal processing and deep learning techniques. First, vibration signals are acquired from the centrifugal pump. The acquired vibration signals are...

  • Article
  • Open Access
66 Citations
5,138 Views
21 Pages

25 September 2023

A hybrid deep learning approach was designed that combines deep learning with enhanced short-time Fourier transform (STFT) spectrograms and continuous wavelet transform (CWT) scalograms for pipeline leak detection. Such detection plays a crucial role...

  • Article
  • Open Access
2 Citations
1,578 Views
26 Pages

26 October 2025

This paper investigates Electrocardiogram (ECG) rhythm classification using a progressive deep learning framework that combines time–frequency representations with complementary hand-crafted features. In the first stage, ECG signals from the Ph...

  • Article
  • Open Access
11 Citations
3,397 Views
21 Pages

28 January 2024

This paper proposes a new fault diagnosis method for centrifugal pumps by combining signal processing with deep learning techniques. Centrifugal pumps facilitate fluid transport through the energy generated by the impeller. Throughout the operation,...

  • Article
  • Open Access
107 Citations
9,635 Views
25 Pages

22 February 2019

This paper conducts a comparative analysis of deep models in biometrics using scalogram of electrocardiogram (ECG). A scalogram is the absolute value of the continuous wavelet transform coefficients of a signal. Since biometrics using ECG signals are...

  • Article
  • Open Access
15 Citations
4,230 Views
29 Pages

4 December 2021

Rotating machinery is one of the major components of industries that suffer from various faults due to the constant workload. Therefore, a fast and reliable fault diagnosis method is essential for machine condition monitoring. In this study, noise el...

  • Article
  • Open Access
7 Citations
2,618 Views
21 Pages

OculusGraphy: Signal Analysis of the Electroretinogram in a Rabbit Model of Endophthalmitis Using Discrete and Continuous Wavelet Transforms

  • Aleksei Zhdanov,
  • Paul Constable,
  • Sultan Mohammad Manjur,
  • Anton Dolganov,
  • Hugo F. Posada-Quintero and
  • Aleksander Lizunov

Background: The electroretinogram is a clinical test used to assess the function of the photoreceptors and retinal circuits of various cells in the eye, with the recorded waveform being the result of the summated response of neural generators across...

  • Article
  • Open Access
29 Citations
3,450 Views
22 Pages

Milling Machine Fault Diagnosis Using Acoustic Emission and Hybrid Deep Learning with Feature Optimization

  • Muhammad Umar,
  • Muhammad Farooq Siddique,
  • Niamat Ullah and
  • Jong-Myon Kim

12 November 2024

This paper presents a fault diagnosis technique for milling machines based on acoustic emission (AE) signals and a hybrid deep learning model optimized with a genetic algorithm. Mechanical failures in milling machines, particularly in critical compon...

  • Article
  • Open Access
50 Citations
6,005 Views
17 Pages

Epilepsy is a neurological disorder that causes recurrent seizures and sometimes loss of awareness. Around 30% of epileptic patients continue to have seizures despite taking anti-seizure medication. The ability to predict the future occurrence of sei...

  • Article
  • Open Access
22 Citations
5,438 Views
22 Pages

12 November 2019

Grape is an economic crop of great importance and is widely cultivated in China. With the development of remote sensing, abundant data sources strongly guarantee that researchers can identify crop types and map their spatial distributions. However, t...

  • Article
  • Open Access
3 Citations
5,700 Views
17 Pages

The trend of using deep learning techniques to classify arbitrary tasks has grown significantly in the last decade. Such techniques in the background provide a stack of non-linear functions to solve tasks that cannot be solved in a linear manner. Nat...

  • Article
  • Open Access
15 Citations
4,216 Views
19 Pages

Respiratory diseases are among the leading causes of death, with many individuals in a population frequently affected by various types of pulmonary disorders. Early diagnosis and patient monitoring (traditionally involving lung auscultation) are esse...

  • Article
  • Open Access
26 Citations
10,288 Views
19 Pages

20 June 2024

Detecting pipeline leaks is an essential factor in maintaining the integrity of fluid transport systems. This paper introduces an advanced deep learning framework that uses continuous wavelet transform (CWT) images for precise detection of such leaks...

  • Article
  • Open Access
1,619 Views
21 Pages

Optimizing Bearing Fault Diagnosis in Rotating Electrical Machines Using Deep Learning and Frequency Domain Features

  • Eduardo Quiles-Cucarella,
  • Alejandro García-Bádenas,
  • Ignacio Agustí-Mercader and
  • Guillermo Escrivá-Escrivá

13 March 2025

This study uses deep learning techniques to optimize fault diagnosis in rolling element bearings of rotating electrical machines. Leveraging the Case Western Reserve University bearing fault database, the methodology involves transforming one-dimensi...

  • Article
  • Open Access
9 Citations
3,367 Views
18 Pages

28 September 2022

Automatic detection of arrhythmia using electrocardiogram (ECG) and deep learning (DL) is very important to reduce the global death rate from cardiovascular diseases (CVD). Previous studies on automatic arrhythmia detection relied largely on various...

  • Article
  • Open Access
23 Citations
2,872 Views
20 Pages

Advanced Bearing-Fault Diagnosis and Classification Using Mel-Scalograms and FOX-Optimized ANN

  • Muhammad Farooq Siddique,
  • Wasim Zaman,
  • Saif Ullah,
  • Muhammad Umar,
  • Faisal Saleem,
  • Dongkoo Shon,
  • Tae Hyun Yoon,
  • Dae-Seung Yoo and
  • Jong-Myon Kim

15 November 2024

Accurate and reliable bearing-fault diagnosis is important for ensuring the efficiency and safety of industrial machinery. This paper presents a novel method for bearing-fault diagnosis using Mel-transformed scalograms obtained from vibrational signa...

  • Article
  • Open Access
4 Citations
3,333 Views
11 Pages

Texture Analysis is a Useful Tool to Assess the Complexity Profile of Microcirculatory Blood Flow

  • Henrique Silva,
  • Hugo A. Ferreira,
  • Clemente Rocha and
  • Luís Monteiro Rodrigues

30 January 2020

The quantitative assessment of cardiovascular functions is particularly complicated, especially during any physiological challenge (e.g., exercise), with physiological signals showing intricate oscillatory properties. Signal complexity is one of such...

  • Article
  • Open Access
1 Citations
2,597 Views
24 Pages

Impact Evaluation of Sound Dataset Augmentation and Synthetic Generation upon Classification Accuracy

  • Eleni Tsalera,
  • Andreas Papadakis,
  • Gerasimos Pagiatakis and
  • Maria Samarakou

We investigate the impact of dataset augmentation and synthetic generation techniques on the accuracy of supervised audio classification based on state-of-the-art neural networks used as classifiers. Dataset augmentation techniques are applied upon t...

  • Article
  • Open Access
3 Citations
2,079 Views
11 Pages

27 July 2021

Accurately determined acoustic emission (AE) locations provide significant information on fracture systems, such as the orientation of fractures in a geothermal reservoir. To determine the relative source locations among a group of seismic events, si...

  • Article
  • Open Access
23 Citations
5,527 Views
24 Pages

10 November 2019

We evaluated electrocardiogram (ECG) biometrics using pre-configured models of convolutional neural networks (CNNs) with various time-frequency representations. Biometrics technology records a person’s physical or behavioral characteristics in...

  • Article
  • Open Access
2 Citations
2,159 Views
16 Pages

Visual Explanations of Deep Learning Architectures in Predicting Cyclic Alternating Patterns Using Wavelet Transforms

  • Ankit Gupta,
  • Fábio Mendonça,
  • Sheikh Shanawaz Mostafa,
  • Antonio G. Ravelo-García and
  • Fernando Morgado-Dias

Cyclic Alternating Pattern (CAP) is a sleep instability marker defined based on the amplitude and frequency of the electroencephalogram signal. Because of the time and intensive process of labeling the data, different machine learning and automatic a...

  • Article
  • Open Access
37 Citations
5,506 Views
20 Pages

8 November 2019

In this work, an algorithm for the classification of six motor functions from an electroencephalogram (EEG) signal that combines a common spatial pattern (CSP) filter and a continuous wavelet transform (CWT), is investigated. The EEG data comprise si...

  • Article
  • Open Access
1,775 Views
23 Pages

A Novel Hybrid Approach for Drowsiness Detection Using EEG Scalograms to Overcome Inter-Subject Variability

  • Aymen Zayed,
  • Nidhameddine Belhadj,
  • Khaled Ben Khalifa,
  • Carlos Valderrama and
  • Mohamed Hedi Bedoui

5 September 2025

Drowsiness constitutes a significant risk factor in diverse occupational settings, including healthcare, industry, construction, and transportation, contributing to accidents, injuries, and fatalities. Electroencephalography (EEG) signals, offering d...

  • Article
  • Open Access
1 Citations
884 Views
32 Pages

Hybrid Framework for Cartilage Damage Detection from Vibroacoustic Signals Using Ensemble Empirical Mode Decomposition and CNNs

  • Anna Machrowska,
  • Robert Karpiński,
  • Marcin Maciejewski,
  • Józef Jonak,
  • Przemysław Krakowski and
  • Arkadiusz Syta

29 October 2025

This study proposes a hybrid analytical framework for detecting chondromalacia using vibroacoustic (VAG) signals from patients with knee osteoarthritis (OA) and healthy controls (HCs). The methodology combines nonlinear signal decomposition, feature...

  • Article
  • Open Access
16 Citations
5,297 Views
23 Pages

Automated Multi-Scale and Multivariate Geological Logging from Drill-Core Hyperspectral Data

  • Roberto De La Rosa,
  • Raimon Tolosana-Delgado,
  • Moritz Kirsch and
  • Richard Gloaguen

2 June 2022

Hyperspectral drill-core scanning adds value to exploration campaigns by providing continuous, high-resolution mineralogical data over the length of entire boreholes. However, multivariate mineralogical data must be transformed into lithological doma...

  • Article
  • Open Access
227 Citations
11,923 Views
16 Pages

4 May 2018

Fault diagnosis is critical to ensure the safety and reliable operation of rotating machinery. Most methods used in fault diagnosis of rotating machinery extract a few feature values from vibration signals for fault diagnosis, which is a dimensionali...

  • Article
  • Open Access
31 Citations
7,826 Views
22 Pages

Fall Detection from Electrocardiogram (ECG) Signals and Classification by Deep Transfer Learning

  • Fatima Sajid Butt,
  • Luigi La Blunda,
  • Matthias F. Wagner,
  • Jörg Schäfer,
  • Inmaculada Medina-Bulo and
  • David Gómez-Ullate

3 February 2021

Fall is a prominent issue due to its severe consequences both physically and mentally. Fall detection and prevention is a critical area of research because it can help elderly people to depend less on caregivers and allow them to live and move more i...

  • Article
  • Open Access
66 Citations
10,405 Views
15 Pages

A Method for Pipeline Leak Detection Based on Acoustic Imaging and Deep Learning

  • Sajjad Ahmad,
  • Zahoor Ahmad,
  • Cheol-Hong Kim and
  • Jong-Myon Kim

17 February 2022

This paper proposes a reliable technique for pipeline leak detection using acoustic emission signals. The acoustic emission signal of a pipeline contains leak-related information. However, the noise in the signal often obscures the leak-related infor...

  • Article
  • Open Access
22 Citations
4,870 Views
18 Pages

Gamma titanium aluminide (γ-TiAl) is considered a high-performance, low-density replacement for nickel-based superalloys in the aerospace industry due to its high specific strength, which is retained at temperatures above 800 °C. However, l...

  • Article
  • Open Access
14 Citations
6,929 Views
19 Pages

28 December 2024

This study introduces an advanced deep-learning framework for the real-time detection of pipeline leaks in smart city infrastructure. The methodology transforms acoustic emission (AE) signals from the time domain into scalogram images using continuou...

  • Article
  • Open Access
9 Citations
2,944 Views
20 Pages

6 March 2024

Among unmanned surface vehicle (USV) components, underwater thrusters are pivotal in their mission execution integrity. Yet, these thrusters directly interact with marine environments, making them perpetually susceptible to malfunctions. To diagnose...

  • Article
  • Open Access
786 Views
19 Pages

23 November 2025

Reliable bearing fault diagnosis plays an important role in maintaining the safety and performance of rotating machinery in industrial systems. Although deep learning models have achieved remarkable success in this field, their dependence on a single...

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