Digital Commons Network^™

Introducing Serendipity In Recommender Systems Through Collaborative Methods, Suboojitha Sridharan

Open Access Master's Theses

Widely used recommendation systems are mainly accuracy-oriented since they are based on item-based ratings and user- or item-based similarity measures. Such accuracy-based engines do not consider factors such as proliferation of varied user interests and the desire for changes. This results in a muted user experience that is generated from a constrained and narrow feature set. Recommender systems should therefore consider other important metrics outside of accuracy such as coverage, novelty, serendipity, unexpectedness and usefulness.

The main focus of this thesis is to both incorporate serendipity into a recommendation engine and improve its quality using the widely used collaborative filtering …

Non-Local Model For The Spatial Distribution Of Impact Ionization Events In Avalanche Photodiodes, David A. Ramirez, Majeed M. Hayat, Andrew S. Huntington, George M. Williams

Electrical and Computer Engineering Faculty Research and Publications

We report an extension of the analytical dead space multiplication theory that provides the means to theoretically determine the spatial distribution of electron and hole impact-ionization events in an arbitrarily specified heterojunction multiplication region. The model can be used to understand the role of the dead space in regularizing the locations of impact ionization. It can also be utilized to analyze, design, and optimize new generations of ultra-low noise, multistaged gain avalanche photodiodes based upon judiciously energizing and relaxing carriers to enhance electron impact ionization and suppress hole impact ionization.

Ill-Posedness Of The Two-Dimensional Keller-Segel Model In Triebel-Lizorkin Spaces, Chao Deng, John Villavert

School of Mathematical & Statistical Sciences Faculty Publications

This article proves the ill-posedness of the Cauchy problem for the two-dimensional Keller–Segel model in Triebel–Lizorkin spaces, for . In particular, it is shown that solutions can develop norm inflation under certain settings in that the solution can become arbitrarily large after an arbitrarily short time even for small initial data.

Lessons Learned In Establishing Stem Student Cohorts At A Border University And The Effect On Student Retention And Success, Mikhail M. Bouniaev, Immanuel Edinbarough, Bill W. Elliott

School of Mathematical & Statistical Sciences Faculty Publications

The University of Texas at Brownsville (UTB) serves more than 8,000 students in the Lower Rio Grande Valley area and broader Mexico region. UTB is a Hispanic-serving institution that attracts students from the surrounding areas, including the Mexico border region. The College of Science, Mathematics and Technology (CSMT) established a Science, Technology, Engineering, and Mathematics (STEM) cohort program to help the majority of students to earn a degree in a STEM field in the shortest possible time. The challenges and obstacles encountered during the planning and implementation phase of the STEM cohort program are discussed in this paper, as are …

The Evaluation Of Doctor Of Physicaltherapy Students’ Confidence And Satisfaction Using Human Patient Simulation, Brooke O'Connell

Open Access Master's Theses

Doctor of Physical Therapy (DPT) curricula are designed to train physical therapy students to treat patients across a range of treatment needs and settings. However, the ability to provide students with hands on experience in a variety of settings can be limited. Acute care setting experience can be particularly challenging to provide students due to availability issues, legal concerns, and limited clinical opportunities. Human patient simulators; however, are not hindered by the same restrictions. Consequently, simulators provide a valuable resource for students to expand their acute care experience. This study was designed to evaluate the confidence and exposure levels of …

Sea Spray Impact On Momentum Exchanges At The Air-Sea Interface During High Wind Conditions, Yackar L. Mauzole

Open Access Master's Theses

At high wind speeds the drag coefficient, characterizing the momentum transfer at the ocean surface, is known to be lower than extrapolation of the existing bulk parameterizations, which were derived at low to medium wind speeds. We hypothesize that sea spray may be responsible for the reduction of the drag, and investigate its effect through direct numerical simulations (DNS). The Lattice Boltzmann method (LBM) is coupled to a Lagrangian particle tracking approach to model numerically the dispersion of sea spray droplets in air turbulence near the air-sea interface during hurricanes and other strong wind events. Our results suggest that the …

A Comparison Of Different Methods Of Zero-Inflated Data Analysis And Its Application In Health Surveys, Si Yang

Open Access Master's Theses

Count data with excessive zeros and/or over-dispersion are prevalent in a wide variety of disciplines, such as public health, psychology, and environmental science. Different regression models have been proposed to deal with data with a preponderance of zero observations. These approaches include: a. transform the data to make it normal and use ordinary least-squares regression (LST); b. Poisson regression (Poisson); c. negative binomial regression (NB); d. zero-inflated Poisson regression (ZIP); e. zeroinflated negative binomial regression (ZINB); f. zero-altered Poisson regression (ZAP); and g. zero-altered negative binomial regression (ZANB). There is no clear guideline as to which one to use and …

Forecasting Stock Market Returns Volatility, Yanan Li

Open Access Master's Theses

It has been widely known that the stock market is always volatile and full of risk. How to better capture the volatility and decrease risk accordingly has become a main concern for both investors and researchers. In this thesis, the stochastic volatility model with offset mixture of normal distribution is fitted for financial dataset NASDAQ:LLTC daily stock market returns volatility and one-step-ahead prediction is made based on the AR(1) SV model. Bayesian analysis is fully applied for model fitting and parameter estimation. The Markov Chain Monte Carlo algorithm, using the Metropolis Hasting method, the Forward Filtering Backward Sampling and the …

Data Collection And Telemetry System Design For Marine Instrumentation: The Son-O-Mermaid, Donaldo Guevara

Open Access Master's Theses

This Thesis presents a prototype design for Sonobuoy Mobile Earthquake Recorder in Marine Areas by Independent Divers (Son-O-MERMAID), a floating instrument that acts as a freely drifting seismometer that captures acoustic signals caused by distant seismic activity. A first version of Son-O-MERMAID was built and deployed in October of 2012, but due to Hurricane Sandy the device was destroyed and data lost. A major limitation of this device was the fact that acoustic data was collected and stored in a submerged computer at a depth of 2,000 feet and data was only accessible once the device was pulled out of …

Windows Surface Rt Tablet Forensics, Asif Iqbal, Hanan Al Obaidli, Andrew Marrington, Andy Jones

Research outputs 2014 to 2021

Small scale digital device forensics is particularly critical as a result of the mobility of these devices, leading to closer proximity to crimes as they occur when compared to computers. The Windows Surface tablet is one such device, combining tablet mobility with familiar Microsoft Windows productivity tools. This research considers the acquisition and forensic analysis of the Windows Surface RT tablet. We discuss the artifacts of both the Windows RT operating system and third-party applications. The contribution of this research is to provide a road map for the digital forensic examination of Windows Surface RT tablets.

An Information-Theoretic Image Quality Measure: Comparison With Statistical Similarity, Asmhan F. Hassan, Dong Cailin, Zahir M. Hussain

Research outputs 2014 to 2021

We present an information-theoretic approach for structural similarity for assessing gray scale image quality. The structural similarity measure SSIM, proposed in 2004, has been successflly used and verfied. SSIM is based on statistical similarity between the two images. However, SSIM can produce confusing results in some cases where it may give a non-trivial amount of similarity for two different images. Also, SSIM cannot perform well (in detecting similarity or dissimilarity) at low peak signal to noise ratio (PSNR). In this study, we present a novel image similarity measure, HSSIM, by using information - theoretic technique based on joint histogram. The …

A Critical Review Of Habitat Use By Feral Cats And Key Directions For Future Research And Management, Tim S. Doherty, Andrew J. Bengsen, Robert A. Davis

Research outputs 2014 to 2021

Feral cats (Felis catus) have a wide global distribution and cause significant damage to native fauna. Reducing their impacts requires an understanding of how they use habitat and which parts of the landscape should be the focus of management. We reviewed 27 experimental and observational studies conducted around the world over the last 35 years that aimed to examine habitat use by feral and unowned cats. Our aims were to: (1) summarise the current body of literature on habitat use by feral and unowned cats in the context of applicable ecological theory (i.e. habitat selection, foraging theory); (2) develop testable …

Genetic Algorithm With Logistic Regression For Prediction Of Progression To Alzheimer's Disease, Piers Johnson, Luke Vandewater, William Wilson, Paul Maruff, Greg Savage, Petra Graham, Lance S. Macaulay, Kathryn A. Ellis, Cassandra Szoeke, Ralph N. Martins, Christopher Rowe, Colin L. Masters, David Ames, Ping Zhang

Research outputs 2014 to 2021

Assessment of risk and early diagnosis of Alzheimer's disease (AD) is a key to its prevention or slowing the progression of the disease. Previous research on risk factors for AD typically utilizes statistical comparison tests or stepwise selection with regression models. Outcomes of these methods tend to emphasize single risk factors rather than a combination of risk factors. However, a combination of factors, rather than any one alone, is likely to affect disease development. Genetic algorithms (GA) can be useful and efficient for searching a combination of variables for the best achievement (eg. accuracy of diagnosis), especially when the search …

Hybrid Intelligent Model For Software Maintenance Prediction, Abdulrahman Ahmed Bobakr Baqais, Mohammad Alshayeb, Zubair A. Baig

Research outputs 2014 to 2021

Maintenance is an important activity in the software life cycle. No software product can do without undergoing the process of maintenance. Estimating a software’s maintainability effort and cost is not an easy task considering the various factors that influence the proposed measurement. Hence, Artificial Intelligence (AI) techniques have been used extensively to find optimized and more accurate maintenance estimations. In this paper, we propose an Evolutionary Neural Network (NN) model to predict software maintainability. The proposed model is based on a hybrid intelligent technique wherein a neural network is trained for prediction and a genetic algorithm (GA) implementation is used …

Industry Needs And Tertiary Journalism Education: Views From News Editors, Trevor A. Cullen, Stephen Tanner, Marcus O'Donnell, Kerry Green

Research outputs 2014 to 2021

This research paper discusses the findings from a 2012 Australian Learning and Teaching Council (ALTC) sponsored project that canvassed the views of news editors around Australia about the "job readiness" of tertiary educated journalism graduates. The focus of this paper is limited to responses from news editors in Western Australia. Data was collected via face to face interviews with eleven news editors in Perth, Western Australia. The editors work in print, online, broadcast and television and all of them employ journalism graduates. The aim was to assess whether the five university based journalism programs in Perth provide graduates with the …

On-Road Remote Sensing Of Automobile Emissions In The Tulsa Area: Fall 2013, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

Modelling Learning To Count In Humanoid Robots, Marek Rucinski

School of Engineering, Computing and Mathematics Theses

This thesis concerns the formulation of novel developmental robotics models of embodied phenomena in number learning. Learning to count is believed to be of paramount importance for the acquisition of the remarkable fluency with which humans are able to manipulate numbers and other abstract concepts derived from them later in life. The ever-increasing amount of evidence for the embodied nature of human mathematical thinking suggests that the investigation of numerical cognition with the use of robotic cognitive models has a high potential of contributing toward the better understanding of the involved mechanisms. This thesis focuses on two particular groups of …

Wave Farm Impact On The Beach Profile: A Case Study, J. Abanades, D. Greaves, G. Iglesias

School of Engineering, Computing and Mathematics

No abstract provided.

The Antibacterial Effects Of Silver, Titanium Dioxide And Silica Dioxide Nanoparticles Compared To The Dental Disinfectant Chlorhexidine On Streptococcus Mutans Using A Suite Of Bioassays., Alexandros Besinis, Peralta T De, Richard D. Handy

School of Engineering, Computing and Mathematics

Metal-containing nanomaterials have the potential to be used in dentistry for infection control, but little is known about their antibacterial properties. This study investigated the toxicity of silver (Ag), titanium dioxide and silica nanoparticles (NPs) against the oral pathogenic species of Streptococcus mutans, compared to the routine disinfectant, chlorhexidine. The bacteria were assessed using the minimum inhibitory concentration assay for growth, fluorescent staining for live/dead cells, and measurements of lactate. All the assays showed that Ag NPs had the strongest antibacterial activity of the NPs tested, with bacterial growth also being 25-fold lower than that in chlorhexidine. The survival rate …

Application Of A Novel Decision Support System To Assess And Manage Coastal Flood Risk In The Teign Estuary, Uk., Santamaria R Gonzalez, D Simmonds, B Zanuttigh, D Reeve, R Nicholls, R Thompson, S Pan, J Horrillo-Caraballo, S Hoggart, S Hanson, E Penning-Rowsell, A Fox, M Hanley

School of Engineering, Computing and Mathematics

This paper demonstrates the application of a Decision Support System (DSS) developed for decision makers and stakeholders to manage and raise awareness of coastal flood risk. The DSS is a GIS-based framework that predicts flooding consequences and is structured around the Source Pathway Receptor Consequence (SPRC) model. The DSS draws together points of view from engineering, ecology and socio-economics, allowing the comparative assessment of the consequences of a range of management interventions. The utility of the tool is demonstrated through application to an estuary field site - the Teign estuary in UK. Vulnerability maps, generated by the DSS for pre-set …

Is Neolithic Land Use Correlated With Demography? An Evaluation Of Pollen-Derived Land Cover And Radiocarbon-Inferred Demographic Change From Central Europe, Jutta Lechterbeck, Kevan Edinborough, Tim Kerig, Ralph Fyfe, Neil Roberts, Stephen Shennan

School of Geography, Earth and Environmental Sciences

No abstract provided.

Web-Flange Distortional Buckling Of Partially Restrained Cold-Formed Steel Purlins Under Uplift Loading, Wei Bin Yuan, Shanshan Cheng, Long Yuan Li, Boksun Kim

School of Engineering, Computing and Mathematics

No abstract provided.

New Insights Into The Mechanism Of Visible Light Photocatalysis, Suresh Pillai, Swagata Banerjee, Polycarpos Falaras, Kevin O'Shea, John A. Byrne, Dionysios D. Dionysiou

Articles

ABSTRACT: In recent years, the area of developing visible-lightactive photocatalysts based on titanium dioxide has been enormously investigated due to its wide range of applications in energy and environment related fields. Various strategies have been designed to efficiently utilize the solar radiation and to enhance the efficiency of photocatalytic processes. Building on the fundamental strategies to improve the visible light activity of TiO2-based photocatalysts, this Perspective aims to give an insight into many contemporary developments in the field of visible-light-active photocatalysis. Various examples of advanced TiO2 composites have been discussed in relation to their visible light induced photoconversion efficiency, dynamics …

Photocatalytic Activity Indicator Inks For Probing A Wide Range Of Surfaces, Suresh Pillai, Andrew Mills, James Hepburn, David Hazafy, Christopher O'Rourke, Nathan Wells, Josef Krysa, Michal Baudys, Martin Zlamal, Hana Bartkova, Claire E. Hill, Kim R. Winn, Morten E. Simonsen, Erik G. Sogaard, Swagata Banerjee, Rachel Fagan

Articles

Three photocatalyst inks based on the redox dyes, Resazurin (Rz), Basic Blue 66 (BB66) and Acid Violet 7 (AV7, are used to assess the photocatalytic activities of a variety of different materials, such as commercial paint, tiles and glass and laboratory made samples of sol-gel coated glass and paint, which collectively exhibit a wide range of activities that cannot currently be probed by any one of the existing ISO tests. Unlike the ISO tests, the ink tests are fast (typically < 10 min), simple to employ and inexpensive. Previous work indicates that the Rz ink test at least correlates linearly with other photocatalytic tests such as the photomineralisation of stearic acid. The average time to bleach 90% of the key RGB colour component of the ink (red for Rz and BB66 inks) and green for AV7 ink) is determined, ttb(90), for eight samples of each of the different materials tested. Five laboratories conducted the tests and the results revealed an average repeatability and reproducibility of: ca. 11% and ca 21%, respectively, which compare well with those reported for the current ISO tests. Additional work on commercial self-cleaning glass using an Rz ink showed that the change in the red component of the RGB image of the ink correlated linearly with that of the change of absorbance (at 608 nm) (as measured using UV/Vis spectroscopy) and the change in the a* component of the Lab colour analysis of the ink, as measured using diffuse reflectance spectroscopy. As a consequence, all three methods generate the same ttb(90). The advantages of the RGB digital image analysis method are discussed briefly.

Evaluating The Implementation Of Curriculum Development For Sustainable Design In Electrical Services Engineering, Michael Mcdonald, Stephen Donohoe

Conference papers

The professional role of electrical services engineers is evolving and changing to meet the needs of industry, both national and internationally. The current demands throughout the built environment are primarily driven by European Directives and Government policies pertaining to sustainable design, energy reduction and energy efficiency. Thus, it is essential that Ireland’s Higher Education Institutions meet these challenges head on by developing diverse programmes which have sustainability at the core of curriculum design. Moreover, programmes of this nature will ensure that young engineers of the future command key transferable skills and enhance their lifelong learning which is required for today’s …

Energy Saving Developments In Lighting, Kevin Kelly

Books/Book chapters

Recent developments in artificial lighting design, lamp technology and control options provide potential for significant energy savings going forward. Historically, equal illuminance across the whole working plane was the goal of lighting designers, however this is now considered wasteful of energy. For example, in an office setting the working plane was interpreted as the whole plan area of the room at desk height; 300 to 500 lux was specified, depending on whether work was mainly PC based or paper based. This resulted in arrays of lights that provided high levels of lighting throughout the space, whether needed or not, and …

Official Statistics Data Integration Using Copulas, L Dalla Valle

School of Engineering, Computing and Mathematics

No abstract provided.

The Personality Behind Cheating: Behavioural Types And The Feeding Ecology Of Cleaner Fish, Alexander D.M. Wilson, Jens Krause, Je Herbert‐Read, Ashley J.W. Ward

School of Biological and Marine Sciences

AbstractThe complex mutualistic relationship between the cleaner fish (Labroides dimidiatus) and their ‘clients’ in many reef systems throughout the world has been the subject of debate and research interest for decades. Game‐theory models have long struggled with explaining how the mixed strategies of cheating and honesty might have evolved in such a system and while significant efforts have been made theoretically, demonstrating the nature of this relationship empirically remains an important research challenge. Using the experimental framework of behavioural syndromes, we sought to quantitatively assess the relationship between personality and the feeding ecology of cleaner fish to provide novel insights …

Active Authentication For Mobile Devices Utilising Behaviour Profiling, Fudong Li, Nathan Clarke, Maria Papadaki, Paul Dowland

School of Engineering, Computing and Mathematics

No abstract provided.

Weld Residual Stresses Near The Bimetallic Interface In Clad Rpv Steel: A Comparison Between Deep-Hole Drilling And Neutron Diffraction Data, Mn James, M Newby, P Doubell, Dg Hattingh, K Serasli, Dj Smith

School of Engineering, Computing and Mathematics

No abstract provided.