Searched for: author%3A%22Nunez%2C+Alfredo%22
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Zeng, Y. (author), Nunez, Alfredo (author), Li, Z. (author)
A train-borne laser Doppler vibrometer (LDV) directly measures the dynamic response of railway track components from a moving train, which has the potential to complement existing train-borne technologies for railway track monitoring. This paper proposes a holistic methodology to characterize train-borne LDV measurements by combining computer...
journal article 2024
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Fu, J. (author), Nunez, Alfredo (author), De Schutter, B.H.K. (author)
To ensure the reliability of power systems, the independent system operator (ISO) manages the planning process of the maintenance of generation units for generation companies (GENCOs). This paper focuses on a widely studied two-layer long-term predictive maintenance decision making framework in a deregulated environment. In the first layer...
journal article 2023
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Fu, J. (author), Peyghami, Saeed (author), Nunez, Alfredo (author), Blaabjerg, Frede (author), De Schutter, B.H.K. (author)
Predictive maintenance scheduling of modular-multilevel-converters (MMCs) requires estimations of the failure probabilities of MMCs during a period of time in the future. Particularly, the predicted future failure probabilities are influenced by two main factors, the mission profiles of the MMCs and the maintenance decisions on the MMCs...
journal article 2023
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Unsiwilai, S. (author), Wang, L. (author), Nunez, Alfredo (author), Li, Z. (author)
This paper presents a methodology for monitoring transition zones using responses of multiple-axle box acceleration (multi-ABA) measurements. The time–frequency characteristics of the vertical ABA signals from four wheelsets are analyzed. The major contributions are as follows. (1) We propose four key performance indicators (KPIs) to quantify...
journal article 2023
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Kapetanović, M. (author), Nunez, Alfredo (author), van Oort, N. (author), Goverde, R.M.P. (author)
Hydrogen fuel cell multiple unit vehicles are acquiring a central role in the transition process towards carbon neutral trains operation in non-electrified regional railway networks. In addition to their primary role as a transport mean, these vehicles offer significant potential for applications in innovative concepts such as smart grids....
abstract 2023
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Kapetanović, M. (author), Nunez, Alfredo (author), van Oort, N. (author), Goverde, R.M.P. (author)
Hydrogen fuel cell multiple unit vehicles are acquiring a central role in the transition process towards carbon neutral trains operation in non-electrified regional railway networks. In addition to their primary role as a transport mean, these vehicles offer significant potential for applications in innovative concepts such as smart grids....
journal article 2023
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Vernaillen, T. (author), Wang, L. (author), Nunez, Alfredo (author), Dollevoet, R.P.B.J. (author), Li, Z. (author)
This paper presents a big data-based analysis of the rail wear of the whole Belgian railway network measured in 2012 and 2019. Wear rates are reported, discussed, and quantitatively formulated as functions of critical factors in terms of curve radius, annual tonnage (rail age), high rail in curves, an average from both rails in straight...
journal article 2023
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Zeng, Y. (author), Shen, C. (author), Nunez, Alfredo (author), Dollevoet, R.P.B.J. (author), Zhang, Weihua (author), Li, Z. (author)
Operational modal analysis (OMA) enables the identification of modal characteristics under operational loads and conditions. Traditional frequency-domain methods cannot directly capture modal changes over time, while existing time-frequency representations are not sufficiently interpretable due to spurious modes and implicit parameter design....
journal article 2023
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Morales, Raúl (author), Marín, Luis G. (author), Roje, Tomislav (author), Caquilpan, Víctor (author), Sáez, Doris (author), Nunez, Alfredo (author)
Microgrids (MGs) are sustainable solutions for rural zone electrification that use local renewable resources. However, only careful planning at the start of an MG project can ensure its future optimal operation. In this paper, a novel methodology for MG planning by using the uncertainty characterization of renewable resources and demand is...
journal article 2023
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Kapoor, T. (author), Wang, H. (author), Nunez, Alfredo (author), Dollevoet, R.P.B.J. (author)
This article proposes a new framework using physics-informed neural networks (PINNs) to simulate complex structural systems that consist of single and double beams based on Euler–Bernoulli and Timoshenko theories, where the double beams are connected with a Winkler foundation. In particular, forward and inverse problems for the...
journal article 2023
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Zeng, Y. (author), Nunez, Alfredo (author), Li, Z. (author)
Due to train load and aging, the dynamic properties of railway tracks degrade over time and deviate over space, which should be monitored to facilitate track maintenance decisions. A train-borne laser Doppler vibrometer (LDV) can directly measure track vibrations in response to the moving train load, which can be potentially applied to large...
conference paper 2023
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Zeng, Y. (author), Nunez, Alfredo (author), Li, Z. (author)
Speckle noise is a major problem for structural vibration measurements with Laser Doppler vibrometer on moving platform (LDVom) due to its highly random, frequent, and broadband nature, especially at high speeds. This paper develops a new post-processing framework to reduce speckle noise based on a case study of LDVom measurements on railway...
journal article 2022
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Fu, J. (author), Nunez, Alfredo (author), De Schutter, B.H.K. (author)
Natural disasters pose a tremendous risk to the reliability of distribution networks. In this paper, a novel real-time UAV routing strategy for coordination between monitoring and inspection for post-disaster restoration in distribution networks is proposed. With our proposed real-time UAV routing strategy, damages can be inspected by UAVs...
journal article 2022
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Wang, H. (author), Hendriks, J.M. (author), Dollevoet, R.P.B.J. (author), Zoeteman, Arjen (author), Nunez, Alfredo (author)
Aiming to handle the increasing variety and volume of railway infrastructure monitoring data, this paper explores the use of intelligent data fusion methods for automatic anomaly detection of railway catenaries. Three classical data dimensionality reduction methods, namely the principal component analysis (PCA), the autoencoder neural network,...
conference paper 2022
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Fu, J. (author), Nunez, Alfredo (author), De Schutter, B.H.K. (author)
Maintenance of generation units is a measure to ensure the reliability of power systems. In this paper, a novel blockchain-based truthful condition-based maintenance of generation units (T-CBMGU) platform is proposed to innovate and upgrade state-of-the-art CBMGU. In addition, two valid inequalities are proposed to accelerate the convergence...
journal article 2022
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Phusakulkajorn, W. (author), Hendriks, J.M. (author), Moraal, J. (author), Dollevoet, R.P.B.J. (author), Li, Z. (author), Nunez, Alfredo (author)
In this paper, a fuzzy interval-based method is proposed for solving the problem of rail defect detection relying on an on-board measurement system and a multiple spiking neural network architecture. Instead of outputting binary values (defect or not defect), all data will belong to both classes with different spreads that are given by two fuzzy...
conference paper 2022
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Kapetanović, M. (author), Nunez, Alfredo (author), van Oort, N. (author), Goverde, R.M.P. (author)
Non-electrified regional railway lines with typically employed diesel-electric multiple units require alternative propulsion systems to meet increasingly strict emissions regulations. With the aim to identify an optimal alternative to conventional diesel traction, this paper presents a model-based assessment of hydrogen-powered propulsion...
journal article 2022
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Kapetanović, M. (author), Bešinović, Nikola (author), Nunez, Alfredo (author), van Oort, N. (author), Goverde, R.M.P. (author)
The Netherlands have one of the highest rail electrification rates in the EU with over 75% of the railway network electrified (European Comission, 2018), offering environment-friendly trains operation. However, in order to achieve carbon neutral railway sector by 2050, significant investments are required to further improve environmental...
abstract 2022
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Li, Z. (author), Li, S. (author), Zhang, P. (author), Nunez, Alfredo (author), Dollevoet, R.P.B.J. (author)
This paper proposes a new hypothesis for the formation process of short pitch rail corrugation. An FE wheel-track dynamic model is utilized to verify the hypothesis by reproducing corrugation initiation and consistent growth. It is found longitudinal compression modes are responsible for corrugation initiation with necessary initial...
journal article 2022
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Kapoor, T. (author), Wang, H. (author), Nunez, Alfredo (author), Dollevoet, R.P.B.J. (author)
This paper addresses the problem of determining the distribution of the return current in electric railway traction systems. The dynamics of traction return current are simulated in all three space dimensions by informing the neural networks with the Partial Differential Equations (PDEs) known as telegraph equations. In addition, this work...
conference paper 2022
Searched for: author%3A%22Nunez%2C+Alfredo%22
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