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Full-Text Articles in Physical Sciences and Mathematics

Machine Learning With Big Data For Electrical Load Forecasting, Alexandra L'Heureux Jun 2022

Machine Learning With Big Data For Electrical Load Forecasting, Alexandra L'Heureux

Electronic Thesis and Dissertation Repository

Today, the amount of data collected is exploding at an unprecedented rate due to developments in Web technologies, social media, mobile and sensing devices and the internet of things (IoT). Data is gathered in every aspect of our lives: from financial information to smart home devices and everything in between. The driving force behind these extensive data collections is the promise of increased knowledge. Therefore, the potential of Big Data relies on our ability to extract value from these massive data sets. Machine learning is central to this quest because of its ability to learn from data and provide data-driven …


Deep Learning For Load Forecasting With Smart Meter Data: Online And Federated Learning, Mohammad Navid Fekri Apr 2022

Deep Learning For Load Forecasting With Smart Meter Data: Online And Federated Learning, Mohammad Navid Fekri

Electronic Thesis and Dissertation Repository

Electricity load forecasting has been attracting increasing attention because of its importance for energy management, infrastructure planning, and budgeting. In recent years, the proliferation of smart meters has created new opportunities for forecasting on the building and even individual household levels. Machine learning (ML) has achieved great successes in this domain; however, conventional ML techniques require data transfer to a centralized location for model training, therefore, increasing network traffic and exposing data to privacy and security risks. Also, traditional approaches employ offline learning, which means that they are only trained once and miss out on the possibility to learn from …


Multi-Device Data Analysis For Fault Localization In Electrical Distribution Grids, Jacob D L Hunte Apr 2022

Multi-Device Data Analysis For Fault Localization In Electrical Distribution Grids, Jacob D L Hunte

Electronic Thesis and Dissertation Repository

The work presented in this dissertation represents work which addresses some of the main challenges of fault localization methods in electrical distribution grids. The methods developed largely assume access to sophisticated data sources that may not be available and that any data sets recorded by devices are synchronized. These issues have created a barrier to the adoption of many solutions by industry. The goal of the research presented in this dissertation is to address these challenges through the development of three elements. These elements are a synchronization protocol, a fault localization technique, and a sensor placement algorithm.

The synchronization protocol …


The Role Of Transient Vibration Of The Skull On Concussion, Rodrigo Dalvit Carvalho Da Silva Mar 2022

The Role Of Transient Vibration Of The Skull On Concussion, Rodrigo Dalvit Carvalho Da Silva

Electronic Thesis and Dissertation Repository

Concussion is a traumatic brain injury usually caused by a direct or indirect blow to the head that affects brain function. The maximum mechanical impedance of the brain tissue occurs at 450±50 Hz and may be affected by the skull resonant frequencies. After an impact to the head, vibration resonance of the skull damages the underlying cortex. The skull deforms and vibrates, like a bell for 3 to 5 milliseconds, bruising the cortex. Furthermore, the deceleration forces the frontal and temporal cortex against the skull, eliminating a layer of cerebrospinal fluid. When the skull vibrates, the force spreads directly to …


Leveraging Machine Learning Techniques Towards Intelligent Networking Automation, Cesar A. Gomez Aug 2021

Leveraging Machine Learning Techniques Towards Intelligent Networking Automation, Cesar A. Gomez

Electronic Thesis and Dissertation Repository

In this thesis, we address some of the challenges that the Intelligent Networking Automation (INA) paradigm poses. Our goal is to design schemes leveraging Machine Learning (ML) techniques to cope with situations that involve hard decision-making actions. The proposed solutions are data-driven and consist of an agent that operates at network elements such as routers, switches, or network servers. The data are gathered from realistic scenarios, either actual network deployments or emulated environments. To evaluate the enhancements that the designed schemes provide, we compare our solutions to non-intelligent ones. Additionally, we assess the trade-off between the obtained improvements and the …


Longitudinal Partitioning Waveform Relaxation Methods For The Analysis Of Transmission Line Circuits, Tarik Menkad Dec 2020

Longitudinal Partitioning Waveform Relaxation Methods For The Analysis Of Transmission Line Circuits, Tarik Menkad

Electronic Thesis and Dissertation Repository

Three research projects are presented in this manuscript. Projects one and two describe two waveform relaxation algorithms (WR) with longitudinal partitioning for the time-domain analysis of transmission line circuits. Project three presents theoretical results about the convergence of WR for chains of general circuits.

The first WR algorithm uses a assignment-partition procedure that relies on inserting external series combinations of positive and negative resistances into the circuit to control the speed of convergence of the algorithm. The convergence of the subsequent WR method is examined, and fast convergence is cast as a generic optimization problem in the frequency-domain. An automatic …


Optimized Machine Learning Models Towards Intelligent Systems, Mohammadnoor Ahmad Mohammad Injadat Jul 2020

Optimized Machine Learning Models Towards Intelligent Systems, Mohammadnoor Ahmad Mohammad Injadat

Electronic Thesis and Dissertation Repository

The rapid growth of the Internet and related technologies has led to the collection of large amounts of data by individuals, organizations, and society in general [1]. However, this often leads to information overload which occurs when the amount of input (e.g. data) a human is trying to process exceeds their cognitive capacities [2]. Machine learning (ML) has been proposed as one potential methodology capable of extracting useful information from large sets of data [1]. This thesis focuses on two applications. The first is education, namely e-Learning environments. Within this field, this thesis proposes different optimized ML ensemble models to …


Edge-Cloud Iot Data Analytics: Intelligence At The Edge With Deep Learning, Ananda Mohon M. Ghosh May 2020

Edge-Cloud Iot Data Analytics: Intelligence At The Edge With Deep Learning, Ananda Mohon M. Ghosh

Electronic Thesis and Dissertation Repository

Rapid growth in numbers of connected devices, including sensors, mobile, wearable, and other Internet of Things (IoT) devices, is creating an explosion of data that are moving across the network. To carry out machine learning (ML), IoT data are typically transferred to the cloud or another centralized system for storage and processing; however, this causes latencies and increases network traffic. Edge computing has the potential to remedy those issues by moving computation closer to the network edge and data sources. On the other hand, edge computing is limited in terms of computational power and thus is not well suited for …


Numerical Studies Of Electrohydrodynamic Flow Induced By Corona And Dielectric Barrier Discharges, Chaoao Shi Feb 2018

Numerical Studies Of Electrohydrodynamic Flow Induced By Corona And Dielectric Barrier Discharges, Chaoao Shi

Electronic Thesis and Dissertation Repository

Electrohyrodynamic (EHD) flow produced by gas discharges allows the control of airflow through electrostatic forces. Various promising applications of EHD can be considered, but this requires a deeper understanding of the physical mechanisms involved.

This thesis investigates the EHD flow generated by three forms of gas discharge. First, a multiple pin-plate EHD dryer associated with the positive corona discharge is studied using a stationary model. Second, the dynamics of a dielectric barrier discharge (DBD) plasma actuator is simulated with a time-dependent solver. Third, different configurations of the extended DBD are explored to enhance the EHD flow.

The results of the …


Secure Integer Comparisons Using The Homomorphic Properties Of Prime Power Subgroups, Rhys A. Carlton Aug 2017

Secure Integer Comparisons Using The Homomorphic Properties Of Prime Power Subgroups, Rhys A. Carlton

Electronic Thesis and Dissertation Repository

Secure multi party computation allows two or more parties to jointly compute a function under encryption without leaking information about their private inputs. These secure computations are vital in many fields including law enforcement, secure voting and bioinformatics because the privacy of the information is of paramount importance.

One common reference problem for secure multi party computation is the Millionaires' problem which was first introduced by Turing Award winner Yao in his paper "Protocols for secure computation". The Millionaires' problem considers two millionaires who want to know who is richer without disclosing their actual worth.

There are public-key cryptosystems that …


Design Of Radio-Frequency Arrays For Ultra-High Field Mri, Ian R O Connell Jan 2017

Design Of Radio-Frequency Arrays For Ultra-High Field Mri, Ian R O Connell

Electronic Thesis and Dissertation Repository

Magnetic Resonance Imaging (MRI) is an indispensable, non-invasive diagnostic tool for the assessment of disease and function. As an investigational device, MRI has found routine use in both basic science research and medicine for both human and non-human subjects.

Due to the potential increase in spatial resolution, signal-to-noise ratio (SNR), and the ability to exploit novel tissue contrasts, the main magnetic field strength of human MRI scanners has steadily increased since inception. Beginning in the early 1980’s, 0.15 T human MRI scanners have steadily risen in main magnetic field strength with ultra-high field (UHF) 8 T MRI systems deemed to …


Automatic Fracture Orientation Extraction From Sfm Point Clouds, Jon Kissi Oct 2016

Automatic Fracture Orientation Extraction From Sfm Point Clouds, Jon Kissi

Electronic Thesis and Dissertation Repository

Geology seeks to understand the history of the Earth and its surface processes through charac- terisation of surface formations and rock units. Chief among the geologists’ tools are rock unit orientation measurements, such as Strike, Dip and Dip Direction. These allow an understanding of both surface and sub-structure on both the local and macro scale.

Although the way these techniques can be used to characterise geology are well understood, the need to collect these measurements by hand adds time and expense to the work of the geologist, precludes spontaneity in field work, and coverage is limited to where the geologist …


Collective Contextual Anomaly Detection For Building Energy Consumption, Daniel Berhane Araya Aug 2016

Collective Contextual Anomaly Detection For Building Energy Consumption, Daniel Berhane Araya

Electronic Thesis and Dissertation Repository

Commercial and residential buildings are responsible for a substantial portion of total global energy consumption and as a result make a significant contribution to global carbon emissions. Hence, energy-saving goals that target buildings can have a major impact in reducing environmental damage. During building operation, a significant amount of energy is wasted due to equipment and human-related faults. To reduce waste, today's smart buildings monitor energy usage with the aim of identifying abnormal consumption behaviour and notifying the building manager to implement appropriate energy-saving procedures. To this end, this research proposes the \textit{ensemble anomaly detection} (EAD) framework. The EAD is …


Charging Level And Deposition Of Droplets In Electrostatic Painting, Husam Osman Sep 2015

Charging Level And Deposition Of Droplets In Electrostatic Painting, Husam Osman

Electronic Thesis and Dissertation Repository

The process of electrostatic painting has become a very important method of coating in a wide range of industrial applications including those used in the automobile industry. The general principle of spray coating is to deposit liquid droplets or solid powder particles on coated targets having various shapes. The electrostatic coating process consists of three main stages: droplet formation and charging, transportation and deposition. The complication of this process is caused by various factors, such as the physical properties of the material to be used, the appropriate electrical and mechanical conditions and the target surface to be coated, which affects …


Secondary Electrohydrodynamic Flow Generated By Corona And Dielectric Barrier Discharges, Mohammadreza Ghazanchaei Sep 2015

Secondary Electrohydrodynamic Flow Generated By Corona And Dielectric Barrier Discharges, Mohammadreza Ghazanchaei

Electronic Thesis and Dissertation Repository

One of the main goals of applied electrostatics engineering is to discover new perspectives in a wide range of research areas. Controlling the fluid media through electrostatic forces has brought new important scientific and industrial applications. Electric field induced flows, or electrohydrodynamics (EHD), have shown promise in the field of fluid dynamics. Although numerous EHD applications have been explored and extensively studied so far, most of the works are either experimental studies, which are not capable to explain the in depth physics of the phenomena, or detailed analytical studies, which are not time effective. The focus of this study is …


Automated Image Interpretation For Science Autonomy In Robotic Planetary Exploration, Raymond Francis Aug 2014

Automated Image Interpretation For Science Autonomy In Robotic Planetary Exploration, Raymond Francis

Electronic Thesis and Dissertation Repository

Advances in the capabilities of robotic planetary exploration missions have increased the wealth of scientific data they produce, presenting challenges for mission science and operations imposed by the limits of interplanetary radio communications. These data budget pressures can be relieved by increased robotic autonomy, both for onboard operations tasks and for decision- making in response to science data.

This thesis presents new techniques in automated image interpretation for natural scenes of relevance to planetary science and exploration, and elaborates autonomy scenarios under which they could be used to extend the reach and performance of exploration missions on planetary surfaces.

Two …


Estimation Of Hidden Markov Models And Their Applications In Finance, Anton Tenyakov Aug 2014

Estimation Of Hidden Markov Models And Their Applications In Finance, Anton Tenyakov

Electronic Thesis and Dissertation Repository

Movements of financial variables exhibit extreme fluctuations during periods of economic crisis and times of market uncertainty. They are also affected by institutional policies and intervention of regulatory authorities. These structural changes driving prices and other economic indicators can be captured reasonably by models featuring regime-switching capabilities. Hidden Markov models (HMM) modulating the model parameters to incorporate such regime-switching dynamics have been put forward in recent years, but many of them could still be further improved. In this research, we aim to address some of the inadequacies of previous regime-switching models in terms of their capacity to provide better forecasts …


Plasmonic Optical Sensors: Performance Analysis And Engineering Towards Biosensing, Peipei Jia Jun 2014

Plasmonic Optical Sensors: Performance Analysis And Engineering Towards Biosensing, Peipei Jia

Electronic Thesis and Dissertation Repository

Surface plasmon resonance (SPR) sensing for quantitative analysis of chemical reactions and biological interactions has become one of the most promising applications of plasmonics. This thesis focuses on performance analysis for plasmonic sensors and implementation of plamonic optical sensors with novel nanofabrication techniques.

A universal performance analysis model is established for general two-dimensional plasmonic sensors. This model is based on the fundamental facts of surface plasmon theory. The sensitivity only depends on excitation light wavelength as well as dielectric properties of metal and dielectrics. The expression involves no structure-specified parameters, which validates this formula in broad cases of periodic, quasiperiodic …


Image Fusion And Axial Labeling Of The Spine, Brandon Miles Jan 2014

Image Fusion And Axial Labeling Of The Spine, Brandon Miles

Electronic Thesis and Dissertation Repository

In order to improve radiological diagnosis of back pain and spine disease, two new algorithms have been developed to aid the 75% of Canadians who will suffer from back pain in a given year. With the associated medical imaging required for many of these patients, there is a potential for improvement in both patient care and healthcare economics by increasing the accuracy and efficiency of spine diagnosis. A real-time spine image fusion system and an automatic vertebra/disc labeling system have been developed to address this. Both magnetic resonance (MR) images and computed tomography (CT) images are often acquired for patients. …


Reliability Models Applied To Smartphone Applications, Sonia Meskini Aug 2013

Reliability Models Applied To Smartphone Applications, Sonia Meskini

Electronic Thesis and Dissertation Repository

Smartphones have become the most used electronic devices. They carry out most of the functionalities of desktops, offering various useful applications that suit the user’s needs. Therefore, instead of the operator, the user has been the main controller of the device and its applications, therefore its reliability has become an emergent requirement. As a first step, based on collected smartphone applications failure data, we investigated and evaluated the efficacy of Software Reliability Growth Models (SRGMs) when applied to these smartphone data in order to check whether they achieve the same accuracy as in the desktop/laptop area. None of the selected …


Optimization Of A Boundary Element Approach To Electromagnet Design With Application To A Host Of Current Problems In Magnetic Resonance Imaging, Chad T. Harris Aug 2013

Optimization Of A Boundary Element Approach To Electromagnet Design With Application To A Host Of Current Problems In Magnetic Resonance Imaging, Chad T. Harris

Electronic Thesis and Dissertation Repository

Magnetic resonance imaging (MRI) has proven to be a valuable methodological approach in both basic research and clinical practice. However, significant hardware advances are still needed in order to further improve and extend the applications of the technique. The present dissertation predominantly addresses gradient and shim coil design (sub-systems of the MR system).

A design study to investigate gradient performance over a set of surface geometries ranging in curvature from planar to a full cylinder using the boundary element (BE) method is presented. The results of this study serve as a guide for future planar and pseudo-planar gradient systems for …


Preoperative Planning Of Robotics-Assisted Minimally Invasive Cardiac Surgery Under Uncertainty, Hamidreza Azimian Aug 2012

Preoperative Planning Of Robotics-Assisted Minimally Invasive Cardiac Surgery Under Uncertainty, Hamidreza Azimian

Electronic Thesis and Dissertation Repository

In this thesis, a computational framework for patient-specific preoperative planning of Robotics-Assisted Minimally Invasive Cardiac Surgery (RAMICS) is developed. It is expected that preoperative planning of RAMICS will improve the rate of success by considering robot kinematics, patient-specific thoracic anatomy, and procedure-specific intraoperative conditions. Given the significant anatomical features localized in the preoperative computed tomography images of a patient's thorax, port locations and robot orientations (with respect to the patient's body coordinate frame) are determined to optimize characteristics such as dexterity, reachability, tool approach angles and maneuverability. In this thesis, two approaches for preoperative planning of RAMICS are proposed that …


Security On Medical Wireless Sensor Networks, Eric D. Southern Aug 2012

Security On Medical Wireless Sensor Networks, Eric D. Southern

Electronic Thesis and Dissertation Repository

Wireless technology is fast becoming a very important tool for all aspects of communication. An area that lacks a strong implementation for wireless communication is the medical field. Wireless systems could be used by clinicians to be better able to diagnose and monitor patients. The reason behind the lack of adoption in healthcare is due to the need to meet the legislated and perceived requirements of security and privacy when dealing with clinical information. The current methods of wireless authentication are investigated and an existing issue in mobile networks is described and solved with two novel solutions; one solution within …


Electrohydrodynamic Enhancement Of Heat Transfer And Mass Transport In Gaseous Media, Bulk Dielectric Liquids And Dielectric Thin Liquid Films, Seyed Reza Mahmoudi May 2012

Electrohydrodynamic Enhancement Of Heat Transfer And Mass Transport In Gaseous Media, Bulk Dielectric Liquids And Dielectric Thin Liquid Films, Seyed Reza Mahmoudi

Electronic Thesis and Dissertation Repository

Controlling transport phenomena in liquid and gaseous media through electrostatic forces has brought new important scientific and industrial applications. Although numerous EHD applications have been explored and extensively studied so far, the fast-growing technologies, mainly in the semiconductor industry, introduce new challenges and demands. These challenges require enhancement of heat transfer and mass transport in small scales (sometimes in molecular scales) to remove highly concentrated heat fluxes from reduced size devices. Electric field induced flows, or electrohydrodynamics (EHD), have shown promise in both macro and micro-scale devices.

Several existing problems in EHD heat transfer enhancements were investigated in this thesis. …


Three-Dimensional Modeling Of Electrostatic Precipitator Using Hybrid Finite Element - Flux Corrected Transport Technique, Niloofar Farnoosh Oct 2011

Three-Dimensional Modeling Of Electrostatic Precipitator Using Hybrid Finite Element - Flux Corrected Transport Technique, Niloofar Farnoosh

Electronic Thesis and Dissertation Repository

This thesis presents the results of a three-dimensional simulation of the entire precipitation process inside a single-electrode one-stage electrostatic precipitator (ESP). The model was designed to predict the motion of ions, gas and solid particles. The precipitator consists of two parallel grounded collecting plates with a corona electrode mounted at the center, parallel to the plates and excited with a high dc voltage. The complex mutual interaction between the three coexisting phenomena of electrostatic field, fluid dynamics and the particulate transport, which affect the ESP process, were taken into account in all the simulations. The electrostatic field and ionic space …


Addressing Computational Complexity Of High Speed Distributed Circuits Using Model Order Reduction, Ehsan Rasekh Sep 2011

Addressing Computational Complexity Of High Speed Distributed Circuits Using Model Order Reduction, Ehsan Rasekh

Electronic Thesis and Dissertation Repository

Advanced in the fabrication technology of integrated circuits (ICs) over the last couple of years has resulted in an unparalleled expansion of the functionality of microelectronic systems. Today’s ICs feature complex deep-submicron mixed-signal designs and have found numerous applications in industry due to their lower manufacturing costs and higher performance levels. The tendency towards smaller feature sizes and increasing clock rates is placing higher demands on signal integrity design by highlighting previously negligible interconnect effects such as distortion, reflection, ringing, delay, and crosstalk. These effects if not predicted in the early stages of the design cycle can severely degrade circuit …


Impact Of Geomagnetically Induced Currents On Power Transformers, Jonathan E. Berge Apr 2011

Impact Of Geomagnetically Induced Currents On Power Transformers, Jonathan E. Berge

Electronic Thesis and Dissertation Repository

This thesis deals with the impact of Geomagnetically Induced Current (GIC) on power transformers in electrical power systems. A simulator to calculate the flows of GIC in an electrical power network, based on an assumed or measured induced geoelectric potential is proposed. This simulator includes all needed mapping techniques to handle a system that cover a large geographical area.

A correlation between GIC and the reactive power absorbed in the core of the saturated transformer is proposed. That correlation is used to estimate GIC in a transformer utilizing existing reactive power measuring infrastructure within the electrical grid without the need …