Article
Engineering, Electrical & Electronic
Quentin Gueuning, Christophe Craeye, Claude Oestges
Summary: A plane-wave spectrum method is introduced for efficiently calculating radiation integrals for tilted and separated source and observation plates. The method uses fast Laplace transforms with unequal spacing to expedite direct and inverse transforms between spatial and spectral domains.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2022)
Article
Telecommunications
Yanyan Chang, Wei Zhang, Hao Wang, Yanyan Liu
Summary: This method utilizes the characteristics of BCH code and the distribution characteristics of continuous zero roots to achieve fast blind recognition by simplifying the Galois field Fourier transform. By determining whether the continuous zero spectra meet the threshold condition, the code length and relevant positions are identified, and the generator polynomial is reconstructed accordingly.
IEEE COMMUNICATIONS LETTERS
(2021)
Article
Optics
Sen Xiang, Li Liu, Huiping Deng, Jin Wu, You Yang, Li Yu
Summary: The paper introduces phase light field (PLF) and re-formatted phase-epipolar-plane-images (phase EPIs) for depth estimation, and proposes a global cost minimization framework. The beetle antennae search (BAS) optimization algorithm is utilized to find the optimal line for depth estimation. The proposed method achieves significant acceleration compared to state-of-the-art methods while maintaining comparable depth quality.
Article
Engineering, Mechanical
H. P. Hong
Summary: In this study, we propose using the derivatives of the EPSD function to quantify the smoothness of the EPSD function in the context of estimation. We derive equations for estimating EPSD using the S-transform and continuous wavelet transform. We also derive equations for assessing the residual for the estimated EPSD using these transforms. The results indicate that the residual depends on the derivatives of the EPSD function with respect to time and frequency as well as the adopted transform.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2023)
Article
Instruments & Instrumentation
M. A. Makowski, B. S. Victor
Summary: The FFT based method significantly improves the frequency response of the MSE system, providing more accurate signal analysis compared to traditional analog lock-in methods. It operates by using fits to rigorous analytic expressions for the FFT spectral components of the MSE signal.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2021)
Article
Astronomy & Astrophysics
Ruben Krasnopolsky, Mario Ponce Martinez, Hsien Shang, Yao-Huan Tseng, Chien-Chang Yen
Summary: The study presents a novel direct numerical method for calculating gravitational potential and forces without the need for artificial boundary conditions. Numerical results show that the proposed method can achieve second order accuracy in computing both potential and forces.
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
(2021)
Article
Engineering, Electrical & Electronic
Dong Zhang, Hai Wang, Yang Feng, Xiaolin Wang, Gan Liu, Kaizhen Han, Xiao Gong, Jing Liu, Xuepeng Zhan, Jiezhi Chen
Summary: The proposed IMC scheme efficiently implements FFT for noise signal processing using flash memory, demonstrating successful analyses of LFN and RTN signals with matching frequency properties. It achieves high energy efficiency and is extendable to applications like image processing and voice recognition.
IEEE ELECTRON DEVICE LETTERS
(2022)
Article
Optics
Xiangzhe Zhang, Liqing Huang, Jingping Zhu, Ning Zhang, Kang Zong, Lipeng Zhai, Yu Zhang, Yakun Cai, Huimin Wang
Summary: The OPD equations of dual Wollaston prisms with an adjustable air gap are derived using the wave normal tracing method, and their validity is verified. The performance of a novel static birefringent Fourier transform imaging spectrometer based on these prisms is investigated.
Article
Engineering, Electrical & Electronic
Yuan Yan, Riccardo Trinchero, Igor Simone Stievano, Hongjie Li, Yan-Zhao Xie
Summary: This article introduces a fully automatic tool for de-noising PD signals in electrical power networks using STFT and SVD. The method effectively filters out white noise and discrete spectrum noise, leading to positive impacts on the detection of important parameters in PD signals.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2022)
Article
Engineering, Electrical & Electronic
Jorge Alfredo Ardila-Rey, Roger Schurch, Nicolas Medina Poblete, Suganya Govindarajan, Osvaldo Munoz, Bruno Albuquerque de Castro
Summary: This article introduces a novel separation technique based on the temporal and spectral behavior of PD signals, identifying faults in electrical equipment and conducting diagnosis by separating sources based on different parameters.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2021)
Article
Acoustics
Johannes Baumgart, Christoph Fritzsche, Steffen Marburg
Summary: The infrasound levels caused by the blade-tower interaction of a wind turbine need to be corrected to be interpreted as sound pressure level, according to the study by Pilger and Ceranna. A reanalysis of the measured data shows that the low-frequency signal of the wind turbine is about 34 dB lower than the original work. All measured levels at a distance of 200 m from the wind turbine's infrasound signal are well below the hearing threshold.
JOURNAL OF SOUND AND VIBRATION
(2022)
Article
Engineering, Electrical & Electronic
Fang-Jia Yan, Bing-Zhao Li
Summary: This paper addresses a key challenge in graph signal processing by proposing the windowed graph fractional Fourier transform (WGFRFT) and a fast algorithm for it. The robustness and superiority of the algorithm are verified through simulations, demonstrating its practicality in graph clustering applications.
DIGITAL SIGNAL PROCESSING
(2021)
Article
Engineering, Electrical & Electronic
Jun Zhong, Xiaowen Bi, Qin Shu, Dakun Zhang, Xiaopeng Li
Summary: This article introduces a denoising method that determines the decomposition layers from the spectral kurtogram and denoises the reference signal using a 3 sigma threshold, resulting in a more accurate recovery of PD signals by effectively removing white noise.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2021)
Article
Engineering, Electrical & Electronic
Fang-Jia Yan, Bing-Zhao Li
Summary: This paper presents a general framework for extending graph signal processing to directed graphs, by introducing the fractional Hermitian Laplacian matrix and the Directed Graph Fractional Fourier Transform (DGFRFT). Filtering is defined based on the new transform to reduce noise, and the denoising performance is evaluated through numerical experiments using real-world directed graphs.
Article
Physics, Applied
Christopher Emersic, Ian Cotton
Summary: The behavior of partial discharge in unipolar turn-to-turn-like waveforms with short rise times has been studied. It was found that pulse waves generate distinct partial discharge behavior compared to square waves. The likelihood of partial discharge is reduced for pulse waves, requiring higher voltages to trigger comparable discharge activity. Additionally, at lower pressures, discharge activity may occur later after voltage rise, possibly outside the detection window of some instruments.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Article
Chemistry, Analytical
Bruno Albuquerque de Castro, Vitor Vecina dos Santos, Guilherme Beraldi Lucas, Jorge Alfredo Ardila-Rey, Rudolf Ribeiro Riehl, Andre Luiz Andreoli
Summary: This study focuses on differentiating discharge in epoxy resin and Nomex paper, the insulation materials of dry-type insulated transformers, using acoustic emission and Hall-effect sensors. The results indicate that both sensors are promising in this differentiation.
Article
Green & Sustainable Science & Technology
Mohammed Baqer Zaki Yahya Al-quraishi, Shamsul Sarip, Hazilah Mad Kaidi, Jorge Alfredo Ardila-Rey, Firdaus Muhammad-Sukki
Summary: The effects of climate change, caused by the increase in CO2 emissions, are becoming more evident. To address the issues of fossil fuel exhaustion and the need for electricity in remote areas, researchers are advancing renewable energy technologies. This study focuses on designing and simulating a novel deflector to improve the efficiency of vertical water turbines.
Article
Chemistry, Multidisciplinary
Christopher Stoddart, Firdaus Muhammad-Sukki, Mark Anderson, Jorge Alfredo Ardila-Rey, Ahmad Syahrir Ayub, Mohd Firrdhaus Mohd Sahabuddin, Mohd Khairil Rahmat, Mohd Nabil Muhtazaruddin, Muhammad Zulkipli
Summary: Offshore wind power is rapidly developing, with subsidy free bids being introduced by governments such as the Netherlands and Germany. This paper investigates the feasibility of a subsidy free bid for the Scottish government and provides insights into the financial scenarios for implementing such bids. The study concludes that it is indeed possible to adopt a subsidy free bid under the current UK contract for difference scheme.
APPLIED SCIENCES-BASEL
(2022)
Article
Automation & Control Systems
Bruno Albuquerque de Castro, Fabricio Guimaraes Baptista, Jorge Alfredo Ardila-Rey, Francesco Ciampa
Summary: This article proposes a baseline-free damage imaging algorithm based on spatial frequency domain virtual time reversal (SFD-VTR) to enhance defect detection in structural health monitoring (SHM). The algorithm does not require time domain reconstruction of re-emitted signals and optimizes traditional methodologies by excluding signal emissions and digital signal processing steps. Experimental results show that the algorithm is able to accurately localize material flaws in aluminum and composite specimens.
IEEE TRANSACTIONS ON INDUSTRIAL INFORMATICS
(2022)
Article
Automation & Control Systems
Imran Khan, Firdaus Muhammad-Sukki, Jorge Alfredo Ardila Rey, Abdullahi Abubakar Masnd, Saud Jazaa Alshammari, Dag Oivind Madsen
Summary: Energy sustainability is a hot topic, and there are currently two approaches being taken: increasing power consumption for economic progress or maintaining carbon consumption under set limitations. Most governments are pushing renewable growth policies to establish a secure, sustainable, and economical energy system while mitigating climate change consequences.
INTELLIGENT AUTOMATION AND SOFT COMPUTING
(2023)
Article
Engineering, Electrical & Electronic
Guilherme Beraldi Lucas, Bruno Albuquerque De Castro, Jorge Alfredo Ardila-Rey, Adam Glowacz, Jose Vital Ferraz Leao, Andre Luiz Andreoli
Summary: In this article, a novel approach using piezoelectric transducers was proposed for the detection of transient interturn short circuits in three-phase induction motors. The proposed algorithm successfully performed the detection, phase identification, and evolution classification of the short circuits. The experimental results demonstrated the effectiveness of this approach and its improvement over traditional acoustic emission systems.
IEEE SENSORS JOURNAL
(2023)
Article
Polymer Science
Roger Schurch, Osvaldo Munoz, Jorge Ardila-Rey, Pablo Donoso, Vidyadhar Peesapati
Summary: Electrical treeing is a major degradation mechanism in high-voltage polymeric insulation. This study investigated electrical trees in epoxy resin using various partial discharge (PD) analysis techniques, and compared their ability to identify tree bulk-insulation crossing, which is a precursor to failure. The results showed that PD pulse waveform parameters performed the best, as they could identify tree crossing independently of the applied AC voltage amplitude and frequency, making them a robust diagnostic tool for managing high-voltage polymeric insulation assets.
Article
Computer Science, Artificial Intelligence
Carlos Boya-Lara, Omar Rivera-Caballero, Jorge Alfredo Ardila-Rey
Summary: In industrial environments, the identification of partial discharge (PD) is hindered by the presence of PD sources and electrical noise. To overcome this, a source separation process is recommended based on the characteristic parameters of the captured signals. Additionally, a novel clustering technique called Communication with Local Agents (CLA) is proposed to discriminate multiple PD sources and electrical noise, outperforming other clustering techniques in terms of average error rate.
EXPERT SYSTEMS WITH APPLICATIONS
(2023)
Article
Engineering, Electrical & Electronic
Jorge Alfredo Ardila-Rey, Bruno Albuquerque de Castro, Rodrigo Rozas-Valderrama, Luis Orellana, Carlos Boya, Firdaus Muhammad-Sukki, Abdullahi Abubakar Mas'ud
Summary: Partial discharge (PD) detection is crucial for diagnosing the condition of high-voltage equipment insulation system. This study presents experimental measurements that characterize the spectral behavior of PD signals captured with a Vivaldi antenna in the presence of different obstacles in the measurement environment. The results show that the spectral content of PD signals in UHF changes depending on the shape of the obstacles, which can affect the separation and identification of sources.
IEEE SENSORS JOURNAL
(2023)
Review
Engineering, Multidisciplinary
Suganya Govindarajan, Adolfo Morales, Jorge Alfredo Ardila-Rey, Narasimman Purushothaman
Summary: Power cables must be extremely reliable to avoid revenue losses. Aging phenomena can negatively impact cable insulation. Early detection and assessment of insulation depletion help prevent total failure. This review discusses reactions in cable insulation and provides an overview of PD detection techniques and challenges. Localization methods, computational intelligence approaches, and the implications of deep learning in PD localization are also explored.
Article
Engineering, Electrical & Electronic
Harimurugan Devarajan, Suganya Govindarajan, Jorge Alfredo Ardila-Rey, Swaminathan Venkatraman, Narasimman Purushothaman
Summary: Partial discharge (PD) detection under impulse voltage excitation is important for examining the insulation integrity in transformers. This study proposes a Holo-Hilbert spectral analysis (HHSA) method to assess PD signatures during a lightning impulse (LI) test. The experiments were conducted on a transformer at different voltage levels and a detailed comparison was made with traditional time-frequency techniques. The results show that HHSA can effectively locate the occurrence of PD in the vicinity of transformer winding.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2023)
Article
Engineering, Electrical & Electronic
Osvaldo Munoz, Roger Schurch, Jorge Alfredo Ardila-Rey
Summary: This study proposes a new methodology for identifying the aging stage of electrical trees using the discrete wavelet transform (DWT) and principal component analysis (PCA) to analyze each partial discharge pulse waveform. The results show that electrical trees can be characterized into three stages: initial, valley, and postcrossing, with different behaviors in terms of discharge and tree structure. The study also demonstrates the potential of this method for real power equipment insulation assessment, such as power cables.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2023)
Article
Construction & Building Technology
Nurul Izzati, Sheikh Ahmad Zaki, Hom Bahadur Rijal, Jorge Alfredo Ardila Rey, Aya Hagishima, Nurizzatul Atikha
Summary: The use of an air conditioner is essential in hot and humid climates to provide a comfortable environment. A field study was conducted in Malaysia to understand respondent behavior and develop a model of thermal comfort. The findings suggest that water intake, clothing insulation, and outdoor temperature affect indoor comfort.
Article
Engineering, Electrical & Electronic
Jorge Alfredo Ardila-Rey, Matias Patricio Cerda-Luna, Carlos Beltran Munoz, Bruno Albuquerque de Castro, Suganya Govindarajan
Summary: The electricity sector heavily relies on oil-filled electricity equipment，especially power transformers. Many of these assets have surpassed their useful life or are nearing the end of it, raising concerns about their condition. The monitoring and diagnosis of failures in liquid insulation systems play a crucial role in extending the lifespan of these equipment. However, current measurement systems have limitations, leading to the development of new measurement methods that can provide a more accurate diagnosis without technical-economic restrictions. The article introduces a novel system that utilizes an electronic nose equipped with gas sensors to measure dissolved gases in liquid insulation systems. This innovative approach shows great promise for routine monitoring and diagnosis, offering an efficient and cost-effective solution.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2023)
Review
Computer Science, Information Systems
Dzul Hafez Yacob, Shamsul Sarip, Hazilah Mad Kaidi, Jorge Alfredo Ardila-Rey, Firdaus Muhammad-Sukki
Summary: Ocean waves along the coast are a promising renewable energy source that can be converted into electrical energy using oscillating water column (OWC) technology. Many research projects have been conducted to develop reliable and environmentally friendly power supply systems. This paper discusses the design characteristics and functions of OWC systems, as well as summarizing the current technological developments.
