William Holderbaum

Prof. William Holderbaum

University of Reading, UK
orcid

Research Focus & Metrics

Academic Career Length

25Years (2002-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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23 February 2017 in Medical Engineering & Physics
Verified
Journal Article
Open access
RKRachel C. King
Rachel C. King
EVEmma Villeneuve
Emma Villeneuve
RWRuth J. White
Ruth J. White
R. Simon SherrattR. Simon Sherratt
R. Simon Sherratt
William HolderbaumWilliam Holderbaum
William Holderbaum
WHWilliam S. Harwin
William S. Harwin
Technological advances in sensors and communications have enabled discrete integration into everyday objects, both in the home and about the person. Information gathered by monitoring physiological, behavioural, and social aspects of our lives, can be used to achieve a positive impact on quality of life, health, and well-being. Wearable sensors are at the cusp of becoming truly pervasive, and could be woven into the clothes and accessories that we wear such that they become ubiquitous and transparent. To interpret the complex multidimensional information provided by these sensors, data fusion techniques are employed to provide a meaningful representation of the sensor outputs. This paper is intended to provide a short overview of data fusion techniques and algorithms that can be used to interpret wearable sensor data in the context of health monitoring applications. The application of these techniques are then described in the context of healthcare including activity and ambulatory monitoring, gait analysis, fall detection, and biometric monitoring. A snap-shot of current commercially available sensors is also provided, focusing on their sensing capability, and a commentary on the gaps that need to be bridged to bring research to market.

9 May 2025 in PLOS ONE
Verified
Journal Article
Open access
PDF file
YWYuki Wong
Yuki Wong
ESEileen Lee Ming Su
Eileen Lee Ming Su
CYChe Fai Yeong
Che Fai Yeong
William HolderbaumWilliam Holderbaum
William Holderbaum
CYChenguang Yang
Chenguang Yang
Brain tumors pose a significant medical challenge, necessitating early detection and precise classification for effective treatment. This study aims to address this challenge by introducing an automated brain tumor classification system that utilizes deep learning (DL) and Magnetic Resonance Imaging (MRI) images. The main purpose of this research is to develop a model that can accurately detect and classify different types of brain tumors, including glioma, meningioma, pituitary tumors, and normal brain scans. A convolutional neural network (CNN) architecture with pretrained VGG16 as the base model is employed, and diverse public datasets are utilized to ensure comprehensive representation. Data augmentation techniques are employed to enhance the training dataset, resulting in a total of 17,136 brain MRI images across the four classes. The accuracy of this model was 99.24%, a higher accuracy than other similar works, demonstrating its potential clinical utility. This higher accuracy was achieved mainly due to the utilization of a large and diverse dataset, the improvement of network configuration, the application of a fine-tuning strategy to adjust pretrained weights, and the implementation of data augmentation techniques in enhancing classification performance for brain tumor detection. In addition, a web application was developed by leveraging HTML and Dash components to enhance usability, allowing for easy image upload and tumor prediction. By harnessing artificial intelligence (AI), the developed system addresses the need to reduce human error and enhance diagnostic accuracy. The proposed approach provides an efficient and reliable solution for brain tumor classification, facilitating early diagnosis and enabling timely medical interventions. This work signifies a potential advancement in brain tumor classification, promising improved patient care and outcomes.

5 September 2023 in Energy Reports
Verified
Journal Article
Open access
Feras AlasaliFeras Alasali
Feras Alasali
SSSaad M. Saad
Saad M. Saad
ASAbdelaziz Salah Saidi
Abdelaziz Salah Saidi
AIAwni Itradat
Awni Itradat
William HolderbaumWilliam Holderbaum
William Holderbaum
FEFatima F. Elkuwafi
Fatima F. Elkuwafi

30 May 2014 in Energies
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Journal Article
Open access
PDF file
MRMatthew Rowe
Matthew Rowe
TYTimur Yunusov
Timur Yunusov
Stephen HabenStephen Haben
Stephen Haben
William HolderbaumWilliam Holderbaum
William Holderbaum
BPBen Potter
Ben Potter
Energy storage is a potential alternative to conventional network reinforcement of the low voltage (LV) distribution network to ensure the grid’s infrastructure remains within its operating constraints. This paper presents a study on the control of such storage devices, owned by distribution network operators. A deterministic model predictive control (MPC) controller and a stochastic receding horizon controller (SRHC) are presented, where the objective is to achieve the greatest peak reduction in demand, for a given storage device specification, taking into account the high level of uncertainty in the prediction of LV demand. The algorithms presented in this paper are compared to a standard set-point controller and bench marked against a control algorithm with a perfect forecast. A specific case study, using storage on the LV network, is presented, and the results of each algorithm are compared. A comprehensive analysis is then carried out simulating a large number of LV networks of varying numbers of households. The results show that the performance of each algorithm is dependent on the number of aggregated households. However, on a typical aggregation, the novel SRHC algorithm presented in this paper is shown to outperform each of the comparable storage control techniques.

1 April 2017 in Energy
Verified
Journal Article
Open access
VPVicky Papaioannou
Vicky Papaioannou
SPStefano Pietrosanti
Stefano Pietrosanti
William HolderbaumWilliam Holderbaum
William Holderbaum
Victor BecerraVictor Becerra
Victor Becerra
RMRayner Mayer
Rayner Mayer

23 June 2009 in IEEE Transactions on Automatic Control
Verified
Journal Article
Closed access
JBJames Biggs
James Biggs
William HolderbaumWilliam Holderbaum
William Holderbaum
This note investigates the motion control of an autonomous underwater vehicle (AUV). The AUV is modeled as a nonholonomic system as any lateral motion of a conventional, slender AUV is quickly damped out. The problem is formulated as an optimal kinematic control problem on the Euclidean Group of Motions SE(3) , where the cost function to be minimized is equal to the integral of a quadratic function of the velocity components. An application of the maximum principle to this optimal control problem yields the appropriate Hamiltonian and the corresponding vector fields give the necessary conditions for optimality. For a special case of the cost function, the necessary conditions for optimality can be characterized more easily and we proceed to investigate its solutions. Finally, it is shown that a particular set of optimal motions trace helical paths. Throughout this note we highlight a particular case where the quadratic cost function is weighted in such a way that it equates to the Lagrangian (kinetic energy) of the AUV. For this case, the regular extremal curves are constrained to equate to the AUV's components of momentum and the resulting vector fields are the d'Alembert-Lagrange equations in Hamiltonian form.