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Full-Text Articles in Engineering

Enhancing The Performance Of Nmt Models Using The Data-Based Domain Adaptation Technique For Patent Translation, Maimoonah Ahmed Jul 2023

Enhancing The Performance Of Nmt Models Using The Data-Based Domain Adaptation Technique For Patent Translation, Maimoonah Ahmed

Electronic Thesis and Dissertation Repository

During today’s age of unparalleled connectivity, language and data have become powerful tools capable of enabling effective communication and cross-cultural collaborations. Neural machine translation (NMT) models are especially capable of leveraging linguistic knowledge and parallel corpora to increase global connectivity and act as a tool for the transmission of knowledge. In this thesis, we apply a data-based domain adaptation technique to fine-tune three pre-existing NMT transformer models with attention mechanisms for the task of patent translation from English to Japanese. Languages, especially in the context of patents, can be very nuanced. A clear understanding of the intended meaning requires comprehensive …


Forecasting The Future Capacities Of Superconducting Quantum Computers: Extending Moore's Law Through Machine Learning, Christopher Tam Jul 2023

Forecasting The Future Capacities Of Superconducting Quantum Computers: Extending Moore's Law Through Machine Learning, Christopher Tam

Electronic Thesis and Dissertation Repository

Quantum computing has emerged as a promising technology that can perform certain tasks exponentially faster than classical computers. Despite the potential for quantum computers to revolutionize the field of computing, the development of fault-tolerant quantum computers remains a critical challenge. Moore's Law has accurately predicted the exponential growth in the capacity of classical computers, with transistor capacity doubling roughly every year. This prediction, established in the 1960s, held true until the early 2010s. However, the emergence of quantum computers raises questions about how to predict the rate of development these technologies. This work presents a novel approach using machine learning …


Experimental Investigation Of The Phase Change Process Within Circular Geometries, Kyle Teather Jul 2023

Experimental Investigation Of The Phase Change Process Within Circular Geometries, Kyle Teather

Electronic Thesis and Dissertation Repository

Latent heat thermal energy storage systems have many advantages over sensible-heat-based thermal storage systems, such as an increased energy density with a narrower range of operating temperatures. The main barrier to implementing latent heat storage systems is the low thermal conductivity of typical storage materials, called phase change materials (PCMs). Furthermore, the heat transfer mode in the liquid phase is natural convection, which is influenced by the geometry and orientation of the heat source and sink, thus impacting the phase change pattern and heat transfer. It is critical to have a good understanding of the underlying fundamental physics over the …


Investigation Of Sensorimotor Integration And Control In Parkinson’S Disease Using Haptics-Enabled Robotics And Machine Learning, Yokhesh Krishnasamy Tamilselvam Jul 2023

Investigation Of Sensorimotor Integration And Control In Parkinson’S Disease Using Haptics-Enabled Robotics And Machine Learning, Yokhesh Krishnasamy Tamilselvam

Electronic Thesis and Dissertation Repository

Non-motor symptoms such as perceptual deficits and cognitive impairments, i.e., deficits in executive functions, presented at an early stage of Parkinson’s Disease (PD) substantially affect a PD patient’s quality of life and may contribute to motor impairments. Studies have emphasized the need to better understand these impairments and the abnormalities contributing to them as it provides a means to efficiently manage the disease. Further, due to the early onset of these deficits, the contributing abnormalities may be considered a potential biomarker for early diagnosis of PD. However, the impairments and the contributing abnormalities are not yet fully understood, leading to …


Automatic Classification And Segmentation Of Patterned Martian Ground Using Deep Learning Techniques, Ruthy Brito Jun 2023

Automatic Classification And Segmentation Of Patterned Martian Ground Using Deep Learning Techniques, Ruthy Brito

Electronic Thesis and Dissertation Repository

Science autonomy onboard spacecraft can optimize image return by prioritizing downlink of meaningful data. Martian polygonally cracked ground is actively studied by planetary geologists and may be indicative of subsurface water. Filtering images containing these polygonal features can be used as a case study for science autonomy and to reduce the overhead associated with parsing through Martian surface images. This thesis demonstrates the use of deep learning techniques in the classification of Martian polygonally patterned ground from HiRISE images. Three tasks are considered, a binary classification to identify images containing polygons, multiclass classification distinguishing different polygon types and semantic segmentation …


Framework For Assessing Information System Security Posture Risks, Syed Waqas Hamdani Jun 2023

Framework For Assessing Information System Security Posture Risks, Syed Waqas Hamdani

Electronic Thesis and Dissertation Repository

In today’s data-driven world, Information Systems, particularly the ones operating in regulated industries, require comprehensive security frameworks to protect against loss of confidentiality, integrity, or availability of data, whether due to malice, accident or otherwise. Once such a security framework is in place, an organization must constantly monitor and assess the overall compliance of its systems to detect and rectify any issues found. This thesis presents a technique and a supporting toolkit to first model dependencies between security policies (referred to as controls) and, second, devise models that associate risk with policy violations. Third, devise algorithms that propagate risk when …


Mechanical Response Of The Craniofacial Skeleton To Subfracture Impacts In The Time And Frequency Domains, Paige Merko Jun 2023

Mechanical Response Of The Craniofacial Skeleton To Subfracture Impacts In The Time And Frequency Domains, Paige Merko

Electronic Thesis and Dissertation Repository

Resonant frequencies have been suggested as a mechanism of brain injury since these vibrations can transfer energy into the brain. Study of the vibrational response of the craniofacial skeleton to impact is limited in literature. In this research, four cadaver specimens were impacted at five locations on the craniofacial skeleton. The mechanical response to each impact was compared in the time and frequency domains. Impacts to the maxilla and its associated soft tissues tended to be attenuated, while impacts to the cranial vault, specifically to the occipital, produced the most severe response. Results suggest that the facial skeleton and its …


Multiparametric Classification Of Tumor Treatment Using Ultrasound Microvascular Imaging, Mahsa Bataghva Jun 2023

Multiparametric Classification Of Tumor Treatment Using Ultrasound Microvascular Imaging, Mahsa Bataghva

Electronic Thesis and Dissertation Repository

Ultrasound-based microvascular imaging is a promising technique for evaluating tumor response to antiangiogenic therapy in preclinical settings. However, challenges such as tissue motion and noise can hinder the accuracy and reliability of contrast-free ultrasound imaging. Additionally, there is a lack of consensus on how to best combine different microvascular ultrasound techniques, like contrast-free and contrast-enhanced ultrasound, for detecting treatment response in cancer models. To address these challenges, this thesis proposes an optimal shrinkage singular value decomposition (SVD) based clutter filtering method. The proposed method significantly enhances visualization and microvascular quantification by increasing the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR). …


Experimental Evaluation Of Abl And Downburst Wind Loads On An Elevated Building, Kate Current Jun 2023

Experimental Evaluation Of Abl And Downburst Wind Loads On An Elevated Building, Kate Current

Electronic Thesis and Dissertation Repository

Elevated low-rise buildings are vulnerable to cladding damage underneath the structure due to extreme winds and the absence of proper wind loading codes and standards such as the National Building Code of Canada (NBCC). The space between the ground and the horizontal base surface of an elevated structure affects its aerodynamics differently compared to a ground-mounted structure. Despite the widespread use of elevated low-rise buildings, there is still limited understanding of the wind interaction across building surfaces for different stilt heights and wind types. This research aims to evaluate the impact of atmospheric boundary layer (ABL) and downburst wind loads …


Catalytic Consequences Of Catalyst Pellet Architecture On The Methanol To Oxymethylene Process, Sebastian M K Cook Jun 2023

Catalytic Consequences Of Catalyst Pellet Architecture On The Methanol To Oxymethylene Process, Sebastian M K Cook

Electronic Thesis and Dissertation Repository

A critical step for the synthesis of renewable oxy methyl ethers (OME) targeted towards diesel substitution, is the catalytic production of a dimethoxymethane/formaldehyde mixture from methanol and air. The bifunctional catalyst requirements needed for methanol to undergo both the acidic and oxidative steps required for dimethoxymethane formation have been recently established for TiO2-supported vanadia catalysts. However, translating these requirements to a catalyst capable of industrial operation remains a challenge. This thesis examines the considerations and adjustments needed to translate the molecular active phase to a large-scale catalytic pellet, including active phase distribution and possibility of hot-spot creation during …


Evaluation Of Dna Minicircles For Delivery Of Adenine Base Editors Using Activatable Reporter Imaging Systems, Shirley Liu Jun 2023

Evaluation Of Dna Minicircles For Delivery Of Adenine Base Editors Using Activatable Reporter Imaging Systems, Shirley Liu

Electronic Thesis and Dissertation Repository

Base editing is a powerful genome editing tool with the potential to treat thousands of genetic diseases caused by single-base changes in DNA called point mutations. Adenine base editors (ABEs) specifically convert adenine (A) to guanine (G) and can theoretically correct almost half of all disease-causing point mutations. Currently, there is a need for a safe and efficient method of delivering ABEs into tissues. In Chapter 2, we developed DNA minicircles as a novel non-viral delivery method for ABEs. To assess delivery efficiency, we also developed activatable reporter imaging systems for the visualization of ABE activity using fluorescence or bioluminescence …


Development And Validation Of Mechatronic Systems For Image-Guided Needle Interventions And Point-Of-Care Breast Cancer Screening With Ultrasound (2d And 3d) And Positron Emission Mammography, Claire Ks Park May 2023

Development And Validation Of Mechatronic Systems For Image-Guided Needle Interventions And Point-Of-Care Breast Cancer Screening With Ultrasound (2d And 3d) And Positron Emission Mammography, Claire Ks Park

Electronic Thesis and Dissertation Repository

The successful intervention of breast cancer relies on effective early detection and definitive diagnosis. While conventional screening mammography has substantially reduced breast cancer-related mortalities, substantial challenges persist in women with dense breasts. Additionally, complex interrelated risk factors and healthcare disparities contribute to breast cancer-related inequities, which restrict accessibility, impose cost constraints, and reduce inclusivity to high-quality healthcare. These limitations predominantly stem from the inadequate sensitivity and clinical utility of currently available approaches in increased-risk populations, including those with dense breasts, underserved and vulnerable populations.

This PhD dissertation aims to describe the development and validation of alternative, cost-effective, robust, and high-resolution …


Hydrothermal Liquefaction (Htl) Of Lignocellulosic Biomass For Biocrude Production: Reaction Kinetics And Corrosion-Resistance Performance Of Candidate Alloys For Reactors, Haoyu Wang May 2023

Hydrothermal Liquefaction (Htl) Of Lignocellulosic Biomass For Biocrude Production: Reaction Kinetics And Corrosion-Resistance Performance Of Candidate Alloys For Reactors, Haoyu Wang

Electronic Thesis and Dissertation Repository

In recent years, the rapid increase in the demand for clean energy and green chemicals as well as concerns over the supply and environmental impacts associated with fossil. resources have stimulated intensive research on conversion of bioresources, such as lignocellulosic biomass and biowaste, into energy, fuels, chemicals, and materials.

Hydrothermal liquefaction (HTL) is a unique thermochemical conversion process, particularly applicable for the conversion of wet biomass and biowaste feedstocks. Most of the biomass HTL studies are conducted in batch reactor and focus on the effects of catalysts, reaction temperature and time on production efficiency and chemical properties of the products. …


Geoelectrical Signatures Of Acid-Generating Mine Waste Rock, Difan Su May 2023

Geoelectrical Signatures Of Acid-Generating Mine Waste Rock, Difan Su

Electronic Thesis and Dissertation Repository

Acid mine drainage (AMD) contamination associated with waste rock piles (WRPs) at mining sites is a global concern, and understanding the generation and release of AMD from these piles is highly desirable. Traditional WRP monitoring techniques involve the installation of monitoring wells and periodic core sampling; however, these approaches are invasive, expensive and can only provide data with limited spatial and temporal resolution. An attractive alternative is non-invasive geophysical techniques that can provide non-invasive and continuous information on subsurface features and processes. This thesis aims to investigate the feasibility of the spectral induced polarization (SIP) method for monitoring changes in …


Flow Characterization Over Biomimetic Fish Scale Arrays, Isaac Nr Clapp Mr. Apr 2023

Flow Characterization Over Biomimetic Fish Scale Arrays, Isaac Nr Clapp Mr.

Electronic Thesis and Dissertation Repository

The contributions of drag to energy consumption in the transportation sector are significant and often unavoidable. Biomimetic surfaces are promising as passive drag reduction mechanisms. Among them, fish scale arrays are beneficial in the laminar and transitional flow regimes but lack fundamental understanding. This research addressed this need and investigated the underlying flow mechanisms over fish scale arrays. Experimental measurements revealed the presence of flow recirculation, streamwise velocity streaks, spanwise velocity fluctuations, and wall normal vorticity streaks, all of which play a role in the near wall flow behaviour. Numerical simulations revealed the superior friction drag reduction capabilities of the …


A Novel Two-Stage Ac-Dc Power Converter With Partial Power Processing, Mina Fakhri Apr 2023

A Novel Two-Stage Ac-Dc Power Converter With Partial Power Processing, Mina Fakhri

Electronic Thesis and Dissertation Repository

A two-stage power converter with an AC-DC boost converter and a soft-switched DC-DC full-bridge converter is proposed in this thesis. The first stage has two interleaved modules that perform power factor correction; the second stage converts the output of the first stage to the desired output. An auxiliary circuit with a switch, a small transformer, and passive components is used to turn off the AC-DC converter switches with soft-switching; the auxiliary switch can also be turned on and off softly. The secondary of the auxiliary transformer is connected to the output of the overall converter so that some power can …


Investigation Of Heavy Metal Removal From Synthetic Desalter Effluent Using A Two-Step Approach By Micellar-Enhanced Ultrafiltration And Microbial Fuel Cell, Carlos Munoz-Cupa Apr 2023

Investigation Of Heavy Metal Removal From Synthetic Desalter Effluent Using A Two-Step Approach By Micellar-Enhanced Ultrafiltration And Microbial Fuel Cell, Carlos Munoz-Cupa

Electronic Thesis and Dissertation Repository

Heavy metals in wastewater streams negatively affect the environment due to their high toxicity. Non-conventional heavy metal removal methods show higher efficiencies for the remediation of these pollutants. In this investigation, a two-step approach using micellar-enhanced ultrafiltration (MEUF) and microbial fuel cell (MFC) was investigated to remove copper, manganese, and zinc from a synthetic salt wastewater containing magnesium, sodium, and phenol. This synthetic solution was used to simulate refinery wastewater streams such as desalter effluent. The study was carried out in three phases. In the first phase, a flat plate polyether sulfone membrane was investigated for the MEUF process with …


Exploration Of Force In Movement And Perception In Parkinson’S Disease, Caroline Stefanie Aitken Apr 2023

Exploration Of Force In Movement And Perception In Parkinson’S Disease, Caroline Stefanie Aitken

Electronic Thesis and Dissertation Repository

Parkinson’s Disease (PD) causes force control deficits in upper and lower limbs. About 50% of patients with advanced PD develop freezing of gait (FOG). There is limited research comparing force control in PD with and without FOG, especially in upper limbs. It has been suggested that motor control deficits in PD are related to deficits in kinesthesia, but there is conflicting evidence whether levodopa alleviates kinesthetic deficits. In this thesis, force control was explored using an upper-and-lower-limb haptics-enabled robot in a reaching task, and kinesthesia was investigated using a haptic device in a force discrimination task while participants were on …


Microstructure-Informed Modeling Of Hydrogen Diffusion In Zirconium Polycrystals, Alireza Tondro Apr 2023

Microstructure-Informed Modeling Of Hydrogen Diffusion In Zirconium Polycrystals, Alireza Tondro

Electronic Thesis and Dissertation Repository

Zirconium alloys are widely used in the core of various types of nuclear reactors. During service, the hot water coolant reacts with zirconium and releases hydrogen atoms that ingress into the lattice of the metal alloy. With time, hydrogen concentration exceeds its terminal solid solubility limit in zirconium, and a brittle phase known as zirconium hydride forms. This phase severely deteriorates the mechanical properties of zirconium alloys, leading to safety concerns regarding the integrity of nuclear pressure tubes. This thesis uses a crystal plasticity finite element model coupled with diffusion equations to study the effects of localized deformation at the …


Cluster-Based Station Reporting And Multi-Ap Coordination In Wi-Fi Networks, Zeyad Abdelmageid Apr 2023

Cluster-Based Station Reporting And Multi-Ap Coordination In Wi-Fi Networks, Zeyad Abdelmageid

Electronic Thesis and Dissertation Repository

Due to the few available Wi-Fi channels and the existence of other technologies, the channel selected by an access point (AP) to be assigned to the network is of extreme importance for network performance due to different interference conditions at different channels. While channel selection algorithms have been proposed, very few of them are user-centric, which could incur a large signaling overhead. As a result, in this thesis, a channel selection algorithm with a low-overhead station (STA) reporting mechanism is proposed, which utilizes the spatial correlation of interference by clustering close-by STAs in order to reduce the feedback overhead by …


Identifying Sources Of Error In Computer Navigated Total Knee Arthroplasties Using A Metric On Se(3) And Sensitivity Analyses, Nicole E. Martensson Apr 2023

Identifying Sources Of Error In Computer Navigated Total Knee Arthroplasties Using A Metric On Se(3) And Sensitivity Analyses, Nicole E. Martensson

Electronic Thesis and Dissertation Repository

Throughout the procedure of a computer-navigated total knee arthroplasty (TKA), there are many opportunities for sources of error to be introduced. Identifying these errors can improve surgical outcomes. There is also a lack of accessible methods in available literature for clinicians to perform research in this area using engineering analysis techniques. This thesis aims to provide a greater understanding of the sources of error that can occur pre-bone cut. Possible sources of error include the bony landmark selections and the placement of the cut guide. Using artificial bone models and a 3D point capture system concurrently with a computer-navigation system, …


Implementation Of A Pre-Assessment Module To Improve The Initial Player Experience Using Previous Gaming Information, Rafael David Segistan Canizales Apr 2023

Implementation Of A Pre-Assessment Module To Improve The Initial Player Experience Using Previous Gaming Information, Rafael David Segistan Canizales

Electronic Thesis and Dissertation Repository

The gaming industry has become one of the largest and most profitable industries today. According to market research, the industry revenues will pass $200 Billion and are expected to reach another $20 Billion in 2024. With the industry growing rapidly, players have become more demanding, expecting better content and quality. This means that game studios need new and innovative ways to make their games more enjoyable. One technique used to improve the player experience is DDA (Dynamic Difficulty Adjustment). It leverages the current player state to perform different adjustments during the game to tune the difficulty delivered to the player …


Continuous Authentication In The Digital Age: An Analysis Of Reinforcement Learning And Behavioural Biometrics, Priya Bansal Apr 2023

Continuous Authentication In The Digital Age: An Analysis Of Reinforcement Learning And Behavioural Biometrics, Priya Bansal

Electronic Thesis and Dissertation Repository

This thesis focuses on developing a continuous authentication system using behavioral biometrics to recognize users accessing computing devices. Keystroke dynamics captures the user's unique behavioral biometric, and reward-based reinforcement learning concepts are applied to recognize them throughout the session. The study shows that the proposed system offers an additional layer of security to traditional authentication methods, forming a robust continuous authentication system that can be added to static authentication systems.

Feature extraction technique is applied to enhance performance metrics, and the study concludes that behavioral biometrics are effective in identifying each user, with device information contributing significantly. The research has …


Open-Set Source-Free Domain Adaptation In Fundus Images Analysis, Masoud Pourreza Apr 2023

Open-Set Source-Free Domain Adaptation In Fundus Images Analysis, Masoud Pourreza

Electronic Thesis and Dissertation Repository

Unsupervised domain adaptation (UDA) is crucial in medical image analysis where only the source domain data is labeled. There is a lot of emphasis on the closed-set paradigm in UDA, where the label space is assumed to be the same in all domains. However, medical imaging often has an open-world scenario where the source domain has a limited number of disease categories and the target domain has unknown distinct classes. Also, maintaining the privacy of patients is a crucial aspect of medical research and practice. In this work, we shed light on the Open-Set Domain Adaptation (OSDA) setting on fundus …


Anomaly Detection On Partial Point Clouds For The Purpose Of Identifying Damage On The Exterior Of Spacecrafts, Kaitlin T. Hutton Apr 2023

Anomaly Detection On Partial Point Clouds For The Purpose Of Identifying Damage On The Exterior Of Spacecrafts, Kaitlin T. Hutton

Electronic Thesis and Dissertation Repository

The Canadarm3 is going to operate autonomously aboard the Lunar Gateway space station for the purpose of inspections and repairs. To make the repairs, damage to the spacecraft needs to be detected accurately and automatically. This research investigates methods for training Machine Learning models on 3D point clouds to identify anomalous structural damage. The PointNet algorithm was used to train models on point clouds without affecting their structure. The optimal training data style was found by comparing how well the different styles of data performed at classifying the point cloud testing data. Two different methods of anomaly detection were tested …


Multi-View Contrastive Learning For Unsupervised Domain Adaptation In Brain-Computer Interfaces, Sepehr Asgarian Mar 2023

Multi-View Contrastive Learning For Unsupervised Domain Adaptation In Brain-Computer Interfaces, Sepehr Asgarian

Electronic Thesis and Dissertation Repository

Electroencephalography (EEG) has been widely used to record electromagnetic fields for motor imagery (MI)-based brain-computer interfaces (BCIs). However, collecting MI signals is often time-consuming and challenging to classify due to the inter-subject variability of EEG signals. To address these issues, we propose a novel framework MACNet, which stands for Multi-view Adversarial Contrastive Network. MACNet employs a contrastive learning approach to learn spatial and temporal features in two views, using Riemannian and Euclidean encoders. By jointly extracting underlying features and learning domain-invariant representations in both source and target features, MACNet improves the alignment and accuracy. In addition, we propose a domain …


Autonomous 3d Urban And Complex Terrain Geometry Generation And Micro-Climate Modelling Using Cfd And Deep Learning, Tewodros F. Alemayehu Mar 2023

Autonomous 3d Urban And Complex Terrain Geometry Generation And Micro-Climate Modelling Using Cfd And Deep Learning, Tewodros F. Alemayehu

Electronic Thesis and Dissertation Repository

Sustainable building design requires a clear understanding and realistic modelling of the complex interaction between climate and built environment to create safe and comfortable outdoor and indoor spaces. This necessitates unprecedented urban climate modelling at high temporal and spatial resolution. The interaction between complex urban geometries and the microclimate is characterized by complex transport mechanisms. The challenge to generate geometric and physics boundary conditions in an automated manner is hindering the progress of computational methods in urban design. Thus, the challenge of modelling realistic and pragmatic numerical urban micro-climate for wind engineering, environmental, and building energy simulation applications should address …


Ai Applications On Planetary Rovers, Alexis David Pascual Mar 2023

Ai Applications On Planetary Rovers, Alexis David Pascual

Electronic Thesis and Dissertation Repository

The rise in the number of robotic missions to space is paving the way for the use of artificial intelligence and machine learning in the autonomy and augmentation of rover operations. For one, more rovers mean more images, and more images mean more data bandwidth required for downlinking as well as more mental bandwidth for analyzing the images. On the other hand, light-weight, low-powered microrover platforms are being developed to accommodate the drive for planetary exploration. As a result of the mass and power constraints, these microrover platforms will not carry typical navigational instruments like a stereocamera or a laser …


Using Statistics, Computational Modelling And Artificial Intelligence Methods To Study And Strengthen The Link Between Kinematic Impacts And Mtbis, Andrew Luke Mcconnell Patterson Mar 2023

Using Statistics, Computational Modelling And Artificial Intelligence Methods To Study And Strengthen The Link Between Kinematic Impacts And Mtbis, Andrew Luke Mcconnell Patterson

Electronic Thesis and Dissertation Repository

Mild traumatic brain injuries (mTBIs) are frequently occurring, yet poorly understood, injuries in sports (e.g., ice hockey) and other physical recreation activities where head impacts occur. Helmets are essential pieces of equipment used to protect participants’ heads from mTBIs. Evaluating the performance of helmets to prevent mTBIs using simulations on anatomically accurate computational head finite element models is critically important for advancing the development of safer helmets. Advancing the level of detail in, and access to, such models, and their continued validation through state-of-the-art brain imaging methods and traditional head injury assessment procedures, is also essential to improve safety. The …


Effect Of Ion Irradiation On The Rate Dependence Of Plastic Deformation Of Extruded Zr-2.5%Nb, Konrad P. Mazurkiewicz Mar 2023

Effect Of Ion Irradiation On The Rate Dependence Of Plastic Deformation Of Extruded Zr-2.5%Nb, Konrad P. Mazurkiewicz

Electronic Thesis and Dissertation Repository

The purpose of this thesis is to examine the properties of Zr-2.5%Nb pressure tube material in the transverse direction. Through testing at room temperature, material properties such as the strain hardening, strain rate sensitivity and apparent activation volume were investigated. The effects of Zr+ ion-implantation occurring at 300°C, simulating irradiation-induced damage, and the strain rate of loading on these properties were also investigated.

Two methods of testing were performed: in-situ micro-pillar compressions and nanoindentation testing. Ion-implantation was observed to increase material strength and hardness. However, certain implanted micro-pillars displayed early localized failure that reduced strength. This finding warrants further …