Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 28 of 28

Full-Text Articles in Physical Sciences and Mathematics

Quantitative Metrics For Mutation Testing, Amani M. Ayad Dec 2019

Quantitative Metrics For Mutation Testing, Amani M. Ayad

Dissertations

Program mutation is the process of generating versions of a base program by applying elementary syntactic modifications; this technique has been used in program testing in a variety of applications, most notably to assess the quality of a test data set. A good test set will discover the difference between the original program and mutant except if the mutant is semantically equivalent to the original program, despite being syntactically distinct.

Equivalent mutants are a major nuisance in the practice of mutation testing, because they introduce a significant amount of bias and uncertainty in the analysis of test results; indeed, mutants …


Bio-Inspired Learning And Hardware Acceleration With Emerging Memories, Shruti R. Kulkarni Dec 2019

Bio-Inspired Learning And Hardware Acceleration With Emerging Memories, Shruti R. Kulkarni

Dissertations

Machine Learning has permeated many aspects of engineering, ranging from the Internet of Things (IoT) applications to big data analytics. While computing resources available to implement these algorithms have become more powerful, both in terms of the complexity of problems that can be solved and the overall computing speed, the huge energy costs involved remains a significant challenge. The human brain, which has evolved over millions of years, is widely accepted as the most efficient control and cognitive processing platform. Neuro-biological studies have established that information processing in the human brain relies on impulse like signals emitted by neurons called …


Using Machine Learning Classification Methods To Detect The Presence Of Heart Disease, Nestor Pereira Dec 2019

Using Machine Learning Classification Methods To Detect The Presence Of Heart Disease, Nestor Pereira

Dissertations

Cardiovascular disease (CVD) is the most common cause of death in Ireland, and probably, worldwide. According to the Health Service Executive (HSE) cardiovascular disease accounting for 36% of all deaths, and one important fact, 22% of premature deaths (under age 65) are from CVD.

Using data from the Heart Disease UCI Data Set (UCI Machine Learning), we use machine learning techniques to detect the presence or absence of heart disease in the patient according to 14 features provide for this dataset. The different results are compared based on accuracy performance, confusion matrix and area under the Receiver Operating Characteristics (ROC) …


Factor Analysis Of Mixed Data (Famd) And Multiple Linear Regression In R, Nestor Pereira Dec 2019

Factor Analysis Of Mixed Data (Famd) And Multiple Linear Regression In R, Nestor Pereira

Dissertations

In the previous projects, it has been worked to statistically analysis of the factors to impact the score of the subjects of Mathematics and Portuguese for several groups of the student from secondary school from Portugal.

In this project will be interested in finding a model, hypothetically multiple linear regression, to predict the final score, dependent variable G3, of the student according to some features divide into two groups. One group, analyses the features or predictors which impact in the final score more related to the performance of the students, means variables like study time or past failures. The second …


Towards Completely Automated Glycan Synthesis, Matteo Panza Nov 2019

Towards Completely Automated Glycan Synthesis, Matteo Panza

Dissertations

Carbohydrates are ubiquitous both in nature as biologically active compounds and in medicine as pharmaceuticals. Although there has been continued interest in the synthesis of carbohydrates, chemical methods require specialized knowledge and hence remain cumbersome. The need for development of rapid, efficient and operationally simple procedures has come to the fore. This dissertation focuses on the development of a fully automated platform that will enable both experts and non-specialists to perform the synthesis of glycans. Existing automated methods for the synthesis of oligosaccharides are highly sophisticated, operationally complex, and require significant user know-how. By contrast, high performance liquid chromatography (HPLC) …


Effects Of Electro-Osmotic Consolidation Of Clays And Its Improvement Using Ion Exchange Membranes, Lucas Martin Aug 2019

Effects Of Electro-Osmotic Consolidation Of Clays And Its Improvement Using Ion Exchange Membranes, Lucas Martin

Dissertations

Electro-osmosis is an established method of expediting consolidation of soft, saturated clayey soils compared to commonly used methods, such as preloading with wick drains. In electro-osmotic consolidation a direct current (DC) is applied via inserted electrodes. This causes hydrated ions in the interstitial fluid to migrate to oppositely charged electrodes. Because the clay particles have a negative surface charge, the majority of ions in the interstitial fluid are positively charged. Therefore, the net flow will be towards the negatively charged electrode (cathode), where the water can be removed and thus consolidation is achieved. Certain problems, such as pH changes in …


Optimal Sampling Paths For Autonomous Vehicles In Uncertain Ocean Flows, Andrew J. De Stefan Aug 2019

Optimal Sampling Paths For Autonomous Vehicles In Uncertain Ocean Flows, Andrew J. De Stefan

Dissertations

Despite an extensive history of oceanic observation, researchers have only begun to build a complete picture of oceanic currents. Sparsity of instrumentation has created the need to maximize the information extracted from every source of data in building this picture. Within the last few decades, autonomous vehicles, or AVs, have been employed as tools to aid in this research initiative. Unmanned and self-propelled, AVs are capable of spending weeks, if not months, exploring and monitoring the oceans. However, the quality of data acquired by these vehicles is highly dependent on the paths along which they collect their observational data. The …


Blind Separation For Intermittent Sources Via Sparse Dictionary Learning, Annan Dong May 2019

Blind Separation For Intermittent Sources Via Sparse Dictionary Learning, Annan Dong

Dissertations

Radio frequency sources are observed at a fusion center via sensor measurements made over slow flat-fading channels. The number of sources may be larger than the number of sensors, but their activity is sparse and intermittent with bursty transmission patterns. To account for this, sources are modeled as hidden Markov models with known or unknown parameters. The problem of blind source estimation in the absence of channel state information is tackled via a novel algorithm, consisting of a dictionary learning (DL) stage and a per-source stochastic filtering (PSF) stage. The two stages work in tandem, with the latter operating on …


Probabilistic Spiking Neural Networks : Supervised, Unsupervised And Adversarial Trainings, Alireza Bagheri May 2019

Probabilistic Spiking Neural Networks : Supervised, Unsupervised And Adversarial Trainings, Alireza Bagheri

Dissertations

Spiking Neural Networks (SNNs), or third-generation neural networks, are networks of computation units, called neurons, in which each neuron with internal analogue dynamics receives as input and produces as output spiking, that is, binary sparse, signals. In contrast, second-generation neural networks, termed as Artificial Neural Networks (ANNs), rely on simple static non-linear neurons that are known to be energy-intensive, hindering their implementations on energy-limited processors such as mobile devices. The sparse event-based characteristics of SNNs for information transmission and encoding have made them more feasible for highly energy-efficient neuromorphic computing architectures. The most existing training algorithms for SNNs are based …


Supercapacitors With Gate Electrodes, Tazima Selim Chowdhury May 2019

Supercapacitors With Gate Electrodes, Tazima Selim Chowdhury

Dissertations

A new approach to improve the capacitance of supercapacitors (SC) is proposed in this study. A typical SC is composed of an anode and a cathode; a separator in between them assures an unintentional discharge of the capacitor. The study focuses on a family of structured separators, either electronically active or passive which are called gates. An active structured separator layer has been fabricated and analyzed. The structured separator has characteristics of electrical diode and is fabricated out of functionalized carbon nanotubes (CNT). Improvement of the overall capacitance of SC, equipped with either active or passive structured separators demonstrated a …


Speciation Of Gaseous Oxidized Mercury Molecules Relevant To Atmospheric And Combustion Environments, Francisco J. Guzman May 2019

Speciation Of Gaseous Oxidized Mercury Molecules Relevant To Atmospheric And Combustion Environments, Francisco J. Guzman

Dissertations

Mercury is a pervasive and highly toxic environmental pollutant. Major anthropogenic sources of mercury emissions include artisanal gold mining, cement production, and combustion of coal. These sources release mostly gaseous elemental mercury (GEM), which upon entering the atmosphere can travel long distances before depositing to environmental waters and landforms. The deposition of GEM is relatively slow, but becomes greatly accelerated when GEM is converted to gaseous oxidized mercury (GOM) because the latter has significantly higher water solubility and lower volatility. Modeling GOM deposition requires the knowledge of its molecular identities, which are poorly known because ultra-trace (tens to hundreds part …


N8- Polynitrogen Stabilized On Carbon-Based Supports As Metal-Free Electrocatalyst For Oxygen Reduction Reaction In Fuel Cells, Zhenhua Yao May 2019

N8- Polynitrogen Stabilized On Carbon-Based Supports As Metal-Free Electrocatalyst For Oxygen Reduction Reaction In Fuel Cells, Zhenhua Yao

Dissertations

The sluggish oxygen reduction reaction (ORR) kinetics at the cathode is one of the key factors limiting the performance of polymer electrolyte membrane fuel cell (PEMFC). Platinum-based materials are the most widely studied catalysts for this ORR reaction while their large-scale practical application in fuel cells is hindered due to their scarcity and low stability. Therefore, highly active, low cost and robust non-Pt catalysts are being developed to overcome the drawbacks. Recently, a novel polynitrogen N8- (PN) stabilized on multiwall carbon nanotube (MWNT) was synthesized under ambient condition for the first time by our group and demonstrated high ORR activities. …


Surface-Enhanced Raman Detection Of Glucose On Several Novel Substrates For Biosensing Applications, Laila Saad Alqarni May 2019

Surface-Enhanced Raman Detection Of Glucose On Several Novel Substrates For Biosensing Applications, Laila Saad Alqarni

Dissertations

The small normal Raman cross-section of glucose is considered to be a major challenge for its detection by Surface Enhanced Raman Spectroscopy (SERS) for medical applications. These applications include blood glucose level monitoring of diabetic patients and evaluation of patients with other medical conditions, since glucose is a marker for many human diseases. This dissertation focuses on Surface-Enhanced Raman Scattering primarily for the detection of glucose. Some experiments also are carried out for the detection of the corresponding enzyme glucose oxidase that is used in electrochemical glucose sensors and in biofuel cells. This project explores the possibility of utilizing Surface …


Workload Allocation In Mobile Edge Computing Empowered Internet Of Things, Qiang Fan May 2019

Workload Allocation In Mobile Edge Computing Empowered Internet Of Things, Qiang Fan

Dissertations

In the past few years, a tremendous number of smart devices and objects, such as smart phones, wearable devices, industrial and utility components, are equipped with sensors to sense the real-time physical information from the environment. Hence, Internet of Things (IoT) is introduced, where various smart devices are connected with each other via the internet and empowered with data analytics. Owing to the high volume and fast velocity of data streams generated by IoT devices, the cloud that can provision flexible and efficient computing resources is employed as a smart "brain" to process and store the big data generated from …


Fouling And Aging In Membrane Filtration : Hybrid Afm-Based Characterization, Modelling And Reactive Membrane Design, Wanyi Fu May 2019

Fouling And Aging In Membrane Filtration : Hybrid Afm-Based Characterization, Modelling And Reactive Membrane Design, Wanyi Fu

Dissertations

Membrane filtration has been extensively used in water and wastewater treatment, desalination, dairy making, and biomass/water separation. However, membrane fouling, aging and insufficient removal efficiency for dissolved organic matters remain major challenges for wider industrial applications. In order to tackle these challenges, this doctoral dissertation investigates mechanisms of membrane fouling and development of antifouling membrane filtration technologies. Specifically, four major research areas are explored: (i) nanoscale physicochemical characterization of the chemically modified polymeric membranes; (ii) quantitative modelling between membrane properties and membrane fouling and defouling kinetics; (iii) development of quantitative structure-activity relationships for membranes that undergo thermal and chemical aging …


“Polysoaps” Via Raft Copolymerization To Form Well-Defined Micelles For Water Remediation And Targeted Drug Delivery Applications, Phillip Pickett May 2019

“Polysoaps” Via Raft Copolymerization To Form Well-Defined Micelles For Water Remediation And Targeted Drug Delivery Applications, Phillip Pickett

Dissertations

Amphiphilic copolymers have become increasingly important for environmental and biological applications due to their behavioral characteristics in aqueous solution. For example, structurally-tailored statistical amphiphilic copolymers or “polysoaps” can self-assemble into micelles or other architectures in water at various concentrations. Polysoaps may be differentiated from small molecule surfactant micelles in their capability to self-assemble into unimolecular associates (unimolecular micelles) with no dependence on concentration. Such micelles offer enormous potential for dispersion of hydrophobic species in water at high dilution. Importantly, each polymer chain forms its own micelle and upon dilution, these micelles remain intact and capable of dispersing hydrocarbon material in …


Engineering Multifunctional And Morphologically Diverse Polymer Brush Surfaces, Cassandra M. Reese May 2019

Engineering Multifunctional And Morphologically Diverse Polymer Brush Surfaces, Cassandra M. Reese

Dissertations

The combination of surface-initiated polymerization (SIP) and post-polymerization (PPM) serves as a powerful approach to fabricate complex, multifunctional polymer films, which can be precisely tuned for desired surface engineering applications. Careful manipulation of PPM parameters such as reaction conditions, the tethered brush parameters, and the physical properties of the unbound post-modifier greatly influence the depth of penetration of the post-modifier and the polymer brush compositional heterogeneity. This dissertation focuses on engineering polymer brush surfaces with multifunctional chemistries and tunable morphologies by investigating the PPM parameters that dictate the distribution of post-modifiers on grafted polymer brush surfaces.

The first chapter of …


Forecasting Anomalous Events And Performance Correlation Analysis In Event Data, Sonya Leech [Thesis] Jan 2019

Forecasting Anomalous Events And Performance Correlation Analysis In Event Data, Sonya Leech [Thesis]

Dissertations

Classical and Deep Learning methods are quite common approaches for anomaly detection. Extensive research has been conducted on single point anomalies. Collective anomalies that occur over a set of two or more durations are less likely to happen by chance than that of a single point anomaly. Being able to observe and predict these anomalous events may reduce the risk of a server’s performance. This paper presents a comparative analysis into time-series forecasting of collective anomalous events using two procedures. One is a classical SARIMA model and the other is a deep learning Long-Short Term Memory (LSTM) model. It then …


An Investigation Into The Predictive Capability Of Customer Spending In Modelling Mortgage Default, Donal Finn [Thesis] Jan 2019

An Investigation Into The Predictive Capability Of Customer Spending In Modelling Mortgage Default, Donal Finn [Thesis]

Dissertations

The mortgage arrears crisis in Ireland was and is among the most severe experienced on record and although there has been a decreasing trend in the number of mortgages in default in the past four years, it still continues to cause distress to borrowers and vulnerabilities to lenders. There are indications that one of the main factors associated with mortgage default is loan affordability, of which the level of disposable income is a driver. Additionally, guidelines set out by the European Central Bank instructed financial institutions to adopt measures to further reduce and prevent loans defaulting, including the implementation and …


Multi-Sensory Deep Learning Architectures For Slam Dunk Scene Classification, Paul Minogue Jan 2019

Multi-Sensory Deep Learning Architectures For Slam Dunk Scene Classification, Paul Minogue

Dissertations

Basketball teams at all levels of the game invest a considerable amount of time and effort into collecting, segmenting, and analysing footage from their upcoming opponents previous games. This analysis helps teams identify and exploit the potential weaknesses of their opponents and is commonly cited as one of the key elements required to achieve success in the modern game. The growing importance of this type of analysis has prompted research into the application of computer vision and audio classification techniques to help teams classify scoring sequences and key events using game footage. However, this research tends to focus on classifying …


An Evaluation Of The Information Security Awareness Of University Students, Alan Pike Jan 2019

An Evaluation Of The Information Security Awareness Of University Students, Alan Pike

Dissertations

Between January 2017 and March 2018, it is estimated that more than 1.9 billion personal and sensitive data records were compromised online. The average cost of a data breach in 2018 was reported to be in the region of US$3.62 million. These figures alone highlight the need for computer users to have a high level of information security awareness (ISA). This research was conducted to establish the ISA of students in a university. There were three aspects to this piece of research. The first was to review and analyse the security habits of students in terms of their own personal …


Noise Reduction In Eeg Signals Using Convolutional Autoencoding Techniques, Conor Hanrahan Jan 2019

Noise Reduction In Eeg Signals Using Convolutional Autoencoding Techniques, Conor Hanrahan

Dissertations

The presence of noise in electroencephalography (EEG) signals can significantly reduce the accuracy of the analysis of the signal. This study assesses to what extent stacked autoencoders designed using one-dimensional convolutional neural network layers can reduce noise in EEG signals. The EEG signals, obtained from 81 people, were processed by a two-layer one-dimensional convolutional autoencoder (CAE), whom performed 3 independent button pressing tasks. The signal-to-noise ratios (SNRs) of the signals before and after processing were calculated and the distributions of the SNRs were compared. The performance of the model was compared to noise reduction performance of Principal Component Analysis, with …


Predicting Violent Crime Reports From Geospatial And Temporal Attributes Of Us 911 Emergency Call Data, Vincent Corcoran Jan 2019

Predicting Violent Crime Reports From Geospatial And Temporal Attributes Of Us 911 Emergency Call Data, Vincent Corcoran

Dissertations

The aim of this study is to create a model to predict which 911 calls will result in crime reports of a violent nature. Such a prediction model could be used by the police to prioritise calls which are most likely to lead to violent crime reports. The model will use geospatial and temporal attributes of the call to predict whether a crime report will be generated. To create this model, a dataset of characteristics relating to the neighbourhood where the 911 call originated will be created and combined with characteristics related to the time of the 911 call. Geospatial …


Enhancing Partially Labelled Data: Self Learning And Word Vectors In Natural Language Processing, Eamon Mcentee Jan 2019

Enhancing Partially Labelled Data: Self Learning And Word Vectors In Natural Language Processing, Eamon Mcentee

Dissertations

There has been an explosion in unstructured text data in recent years with services like Twitter, Facebook and WhatsApp helping drive this growth. Many of these companies are facing pressure to monitor the content on their platforms and as such Natural Language Processing (NLP) techniques are more important than ever. There are many applications of NLP ranging from spam filtering, sentiment analysis of social media, automatic text summarisation and document classification.


Detection Of Offensive Youtube Comments, A Performance Comparison Of Deep Learning Approaches, Priyam Bansal Jan 2019

Detection Of Offensive Youtube Comments, A Performance Comparison Of Deep Learning Approaches, Priyam Bansal

Dissertations

Social media data is open, free and available in massive quantities. However, there is a significant limitation in making sense of this data because of its high volume, variety, uncertain veracity, velocity, value and variability. This work provides a comprehensive framework of text processing and analysis performed on YouTube comments having offensive and non-offensive contents.

YouTube is a platform where every age group of people logs in and finds the type of content that most appeals to them. Apart from this, a massive increase in the use of offensive language has been apparent. As there are massive volume of new …


Performance Comparison Of Hybrid Cnn-Svm And Cnn-Xgboost Models In Concrete Crack Detection, Sahana Thiyagarajan Jan 2019

Performance Comparison Of Hybrid Cnn-Svm And Cnn-Xgboost Models In Concrete Crack Detection, Sahana Thiyagarajan

Dissertations

Detection of cracks mainly has been a sort of essential step in visual inspection involved in construction engineering as it is the commonly used building material and cracks in them is an early sign of de-basement. It is hard to find cracks by a visual check for the massive structures. So, the development of crack detecting systems generally has been a critical issue. The utilization of contextual image processing in crack detection is constrained, as image data usually taken under real-world situations vary widely and also includes the complex modelling of cracks and the extraction of handcrafted features. Therefore the …


An Evaluation Of Learning Employing Natural Language Processing And Cognitive Load Assessment, Mrunal Tipari Jan 2019

An Evaluation Of Learning Employing Natural Language Processing And Cognitive Load Assessment, Mrunal Tipari

Dissertations

One of the key goals of Pedagogy is to assess learning. Various paradigms exist and one of this is Cognitivism. It essentially sees a human learner as an information processor and the mind as a black box with limited capacity that should be understood and studied. With respect to this, an approach is to employ the construct of cognitive load to assess a learner's experience and in turn design instructions better aligned to the human mind. However, cognitive load assessment is not an easy activity, especially in a traditional classroom setting. This research proposes a novel method for evaluating learning …


Is There A Correlation Between Wikidata Revisions And Trending Hashtags On Twitter?, Paula Dooley [Thesis] Jan 2019

Is There A Correlation Between Wikidata Revisions And Trending Hashtags On Twitter?, Paula Dooley [Thesis]

Dissertations

Twitter is a microblogging application used by its members to interact and stay socially connected by sharing instant messages called tweets that are up to 280 characters long. Within these tweets, users can add hashtags to relate the message to a topic that is shared among users. Wikidata is a central knowledge base of information relying on its members and machines bots to keeping its content up to date. The data is stored in a highly structured format with the added SPARQL protocol and RDF Query Language (SPARQL) endpoint to allow users to query its knowledge base.