Physical Sciences and Mathematics Commons^™

On The Spectral Theory Of Linear Differential-Algebraic Operators With Periodic Coefficients, Bader Alshammari

Theses and Dissertations

In this thesis, the spectral theory of linear differential algebraic equations (DAEs) is considered in detail and extended to treat the weighted spectral theory which generalizes the classical theory, i.e., we develop the spectral theory for the most general DAEs: J df dt + Hf = λWf, (0.0.1) where J is a constant nonzero skew-Hermitian n×n-matrix, both H and W are dperiodic Hermitian n×n-matrices with Lebesgue measurable functions as entries, and W is positive semidefinite and invertible for a.e. t ∈ R (i.e., Lebesgue almost everywhere). Under weakest hypotheses on H and W currently known, called the local index-1 hypotheses, …

Predicting The Impact Of Iot Data Gathering On User’S Privacy Preferences, Ghassen Kilani

Theses and Dissertations

The proliferation of Internet of Things (IoT) devices has increased data sharing, profiling, and manipulation on various networks. The rapid growth of information disclosure has caused system users to lose motivation to enhance their data privacy. The repeated breaches on different networks worldwide have made people feel discouraged, as they perceive privacy schemes as futile. IoT systems introduce another dimension of privacy leakage due to their expendability nature and information collection features. The situation worsens when users have to manage multiple IoT devices, each following different security protocols, leading to poor decision-making and privacy leakage. This tremendous flow of unsecured …

Asynchronous Messaging In A P2p System: Defending Against A Storage Exhaustion Attack On Kademlia Dht, Maxim Biro

Theses and Dissertations

An instant messaging service designed using a peer to peer distributed network architecture has many appealing properties it gets for free: high scalability, cheap operational cost and no reliance on a third party to provide the service. However, the nature of the distributed network architecture makes implementing some of the instant messaging features rather challenging, asynchronous messaging being one of them. The asynchronous messaging requires that peers store arbitrary data on behalf of other peers for prolonged periods of time, often measured in days, which, if not kept in check, can be easily abused by malicious actors by spamming the …

Water Quality Correlations With Phytoplankton Community Composition In A Polluted Shallow Subtropical Estuary, Connor Joseph Wong

Theses and Dissertations

The Indian River Lagoon (IRL) estuary has experienced eutrophication and degraded water quality due to high nutrient input, urbanization, and anthropogenic stressors. High nutrient input and restricted estuarine hydrology promotes algal blooms. Algal blooms or harmful algal blooms (HABs) are a global concern as they can cause negative ecological and economic impacts. The frequency and range of HABs is expected to be exacerbated by climate change and altered oceanic and estuarine conditions. Research on the formation and frequency of HABs is an ongoing global effort, but algal blooms are often dynamic and patchy making them difficult to study. This study …

A Machine Learning Approach To Forecasting Sep Intensity And Times Based On Cme And Other Solar Activities, Peter John Thomas

Theses and Dissertations

High intensity Solar Energetic Particle (SEP) events pose severe risks for astronauts and critical infrastructure. The ability to accurately forecast the peak intensity and times of these events would enable preparatory measures to mitigate much of this risk. Machine learning approaches have the potential to use characteristics of CMEs and other space weather phenomena to predict SEP intensities and times. However, the severe sparsity of SEP events in current datasets poses a problem to traditional machine learning techniques. In this work, we present a dataset of proton event intensities and times, as well as features for corresponding CMEs and space …

Process For Designing And Implementing Provably Verifiable Voting Systems, Kholud Alghamdi

Theses and Dissertations

This research aims to explore processes for designing verifiable voting systems in which certain properties can be proven, exemplified with systems applicable to election processes in Saudi Arabia. The electronic government model has become a substantial channel for governments to connect to businesses and citizens, to develop services, and provide general information. E-voting and in particular online voting is one of the important tools that can be used in political and administrative places where information and communications technology devices and tools are utilized to simplify people’s lives and facilitate the election process and decision making. Election processes let a population …

Artifact Development For The Prediction Of Stress Levels On Higher Education Students Using Machine Learning, Valentina Quiroga, Alejandra Hurtado, José Rojas

ICT

Stress is an adaptative reaction of an organism, human or not, to the demands of fitting in an environment (Kav Vedhara, 1996). When stress originates in an educational context, it is common to refer to it as a student and their mechanisms to adapt and cope with the academic demand. All humans experience stress during their lifetime, but when this overwhelmed feeling is prolonged can affect human behaviour and the ability to deal with physical and emotional pressure, having, as a result, a different range of problems. It is important for higher-level educations institutions, such as colleges and universities, to …

Querai – A Smart Quiz Generator, Elton Da Silva, Fernando Aires Da Silva, Kim Jang Womg, Tai Teei Ho

ICT

QUERAI is a website powered by an Artificial Intelligence Question & Answer quiz generator model aiming to enhance students' learning experience and improve teachers' qualitative work by giving them more time to deal with other activities such as assignment correction, general grading, and class preparation.

Problem Solving For Industry, Jozimar Basilio Ferreira, Nicholas Chibuike-Eruba, José Fernando González Anavia, Jolomi (Oritsejolomi) Sillo

ICT

This project seeks to use reinforcement learning to develop AI agents used to controlled NPCs in video game worlds that are capable of mastering decision tasks in their video game environments. Our job will be to develop algorithms and methods that can effectively train the AI agents using Reinforcement learning, which can be used in various gaming environments and scenarios such as racing games and first-person shooters. We then market these agents to video game developers for use in their game worlds. The developer can use our agents as-is in their game without modifications or they can train them further, …

Smart Property Valuation. Problem Solving For Industry, David Silva, Luiz Augusto Dias, Raul M. Fuzita

ICT

The analysis of this project it is used the CRISP-DM method. Smart Property Valuation (SPV) is a fictional company created by David Silva, Luiz Dias, and Raul Fuzita to analyse, explore, and prove the conception of a model capable of predicting or estimating prices for properties. They believe they can benefit common people, realtors, and construction companies with their solutions. This research is for educational purposes and should be treated as such.

The Use Of Deep Learning Solutions To Develop A Practice Tool To Support Lámh Language For Communication Partners, Gabriel Bueno Pimentel Borges

ICT

This study has proposed an alternative to promote the learning and enhancement of Lámh language for communication partners that support current users by creating a real time detection tool to recognise 20 chosen Lámh signs based on existing studies in the field. This implementation was carried out by generating primary data composed by MediaPipe landmark numpy arrays of 40 frames and 45 repetitions per sign. The Neural Networks were built using the Python library Keras and the applied SVM models were built with the library sklearn. The real time detection was carried out by integrating the mentioned elements with the …

Defining Financial Risks And Market Trends Through Predictive Data Analysis, Marcelle Louise, Luciana Teixeira, Muhammad Shahbaz, Giovanni Andrade

ICT

This project focuses on Dublin short term rental market opportunities, by developing pricing and rate occupancy prediction models based on machine learning approaches to identify patterns that may impact or aid users in making smarter and cost-effective decisions. The concept of this research is to show the financial feasibility of data services, as well as how data science can improve business and operational efficiency.

Irrelevant Pixels Are Everywhere: Find And Exclude Them For More Efficient Computer Vision, Caleb Tung, Abhinav Goel, Xiao Hu, Nick Eliopoulos, Emmanuel Amobi, George K. Thiruvathukal, Vipin Chaudhary, Yung-Hisang Lu

Computer Science: Faculty Publications and Other Works

Computer vision is often performed using Convolutional Neural Networks (CNNs). CNNs are compute-intensive and challenging to deploy on power-constrained systems such as mobile and Internet-of-Things (IoT) devices. CNNs are compute-intensive because they indiscriminately compute many features on all pixels of the input image. We observe that, given a computer vision task, images often contain pixels that are irrelevant to the task. For example, if the task is looking for cars, pixels in the sky are not very useful. Therefore, we propose that a CNN be modified to only operate on relevant pixels to save computation and energy. We propose a …

Iowa Waste Reduction Center Newsletter, July 2022, University Of Northern Iowa. Iowa Waste Reduction Center.

Iowa Waste Reduction Center Newsletter

In this Issue:

--- Iowa Waste Reduction Spotlight
--- Community Training Workshops Kick Off This Week
--- Air Quality Permits Under Review
--- Free On-Site Review
--- Industry News

Towards Aligning Slides And Video Snippets: Mitigating Sequence And Content Mismatches, Ziyuan Liu, Hady W. Lauw

Research Collection School Of Computing and Information Systems

Slides are important form of teaching materials used in various courses at academic institutions. Due to their compactness, slides on their own may not stand as complete reference materials. To aid students’ understanding, it would be useful to supplement slides with other materials such as online videos. Given a deck of slides and a related video, we seek to align each slide in the deck to a relevant video snippet, if any. While this problem could be formulated as aligning two time series (each involving a sequence of text contents), we anticipate challenges in generating matches arising from differences in …

Interannual Variation Of Ichthyofaunal Utilization Of A Man-Made Salt Marsh Creek In Mission Bay, California, Maria Angst

McNair Summer Research Program

Southern California’s wetlands are drastically declining due to human activities. Increasingly, marsh restoration and creation are being used to mitigate such losses. This study used minnow traps to resample the ichthyofauna of a created marsh (Crown Point Mitigation Site; CPMS) and an adjacent natural marsh (Kendall Frost) in Mission Bay, California, 26 years following the marsh creation. These data were compared to data collected from 1995-1998, immediately after marsh creation, and data from 2021. Fishes captured included Fundulus parvipinnis, Gillichthys mirabilis, Acanthagobius flavimanus, Ctenogobius sagittula, and Mugil cephalus. Species richness and dominance measures were higher in the natural relative to …

Navigating Mathematics Teacher Preparation During A Time Of Crisis, Zareen G. Rahman, Rani Satyam, Younggon Bae

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

In this paper we highlight the experience of a mathematics teacher educator (MTE) and their preservice teachers (PTs) in a middle school mathematics methods course during the 2020 shift to online instruction due to the COVID-19 pandemic. We believe it is valuable to report how the MTE reflected on their instructional decision-making in response to this massive transition to remote instruction. We also report that PTs needed support and guidance to employ new teaching practices they had learned in the methods course instead of reverting to familiar teaching methods.

Ultrametric Diffusion, Rugged Energy Landscapes And Transition Networks, Wilson A. Zuniga-Galindo

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

In this article we introduce the ultrametric networks which are p-adic continuous analogues of the standard Markov state models constructed using master equations. A p-adic transition network (or an ultrametric network) is a model of a complex system consisting of a hierarchical energy landscape, a Markov process on the energy landscape, and a master equation. We focus on networks where the transition rates between two different basins are constant functions, and the jumping process inside of each basin is controlled by a p-adic radial function. We solve explicitly the Cauchy problem for the master equation attached to this type of …

Coexistence Of Extended And Localized States In The One-Dimensional Non-Hermitian Anderson Model, Cem Yuce, Hamidreza Ramezani

Physics and Astronomy Faculty Publications and Presentations

In one-dimensional Hermitian tight-binding models, mobility edges separating extended and localized states can appear in the presence of properly engineered quasiperiodical potentials and coupling constants. On the other hand, mobility edges do not exist in a one-dimensional Anderson lattice since localization occurs whenever a diagonal disorder through random numbers is introduced. Here we consider a nonreciprocal non-Hermitian lattice and show that the coexistence of extended and localized states appears with or without diagonal disorder in the topologically nontrivial region. We discuss that the mobility edges appear basically due to the boundary condition sensitivity of the nonreciprocal non-Hermitian lattice.

B ¯ →D (∗)ℓ X ¯ Decays In Effective Field Theory With Massive Right-Handed Neutrinos, Alakabha Datta, Hongkai Liu, Danny Marfatia

Faculty and Student Publications

We calculate the complete differential decay distributions for the B meson decays, B¯→D(∗)ℓX¯, to a massive right-handed (RH) neutrino in the low-energy effective field theory (LEFT) framework. We find that a massive RH neutrino does not introduce any new angular structures compared to the massless case, but can cause significant distortions in angular observables. We study the phenomenology of low-energy four-fermion operators permitted by the standard model effective field theory (SMEFT) extended with RH neutrinos (SMNEFT). We show that to explain the positive value of the difference in forward-backward asymmetries, ΔAFBAFBμ-AFBe, tentatively inferred from Belle data, the RH neutrino must …

The Multisided Complexity Of Fairness In Recommender Systems, Nasim Sonboli, Robin Burke, Michael Ekstrand, Rishabh Mehrotra

Computer Science Faculty Publications and Presentations

Recommender systems are poised at the interface between stakeholders: for example, job applicants and employers in the case of recommendations of employment listings, or artists and listeners in the case of music recommendation. In such multisided platforms, recommender systems play a key role in enabling discovery of products and information at large scales. However, as they have become more and more pervasive in society, the equitable distribution of their benefits and harms have been increasingly under scrutiny, as is the case with machine learning generally. While recommender systems can exhibit many of the biases encountered in other machine learning settings, …

Uncovering Inclusivity Gaps In Design Pedagogy Through The Digital Design Marginalization Framework, Jaisie Sin, Cosmin Munteanu, Michael Nixon, Velian Pandeliev, Garreth W. Tigwell, Kristen Shinohara, Anthony Tang, Steve Szigeti

Research Collection School Of Computing and Information Systems

Designers play a key role in the design of inclusive and socially conscious interfaces. Thus, it is imperative for designers to be thoughtful of the ethical and social implications of design. However, gaps in the foundational training that designers receive (e.g., as university students) can negatively impact their ability to consider the social implications of their design practice. This can result in consequences such as digital marginalization, which, as defined by the Digital Design Marginalization (DDM) framework, is the “pushing away”, whether intentional or not, of a defined group of users from a digital or online service or system, where …

Npc: Neuron Path Coverage Via Characterizing Decision Logic Of Deep Neural Networks, Xiaofei Xie, Tianlin Li, Jian Wang, Lei Ma, Qing Guo, Felix Juefei-Xu, Yang Liu

Research Collection School Of Computing and Information Systems

Deep learning has recently been widely applied to many applications across different domains, e.g., image classification and audio recognition. However, the quality of Deep Neural Networks (DNNs) still raises concerns in the practical operational environment, which calls for systematic testing, especially in safety-critical scenarios. Inspired by software testing, a number of structural coverage criteria are designed and proposed to measure the test adequacy of DNNs. However, due to the blackbox nature of DNN, the existing structural coverage criteria are difficult to interpret, making it hard to understand the underlying principles of these criteria. The relationship between the structural coverage and …

Gbgallery: A Benchmark And Framework For Game Testing, Zhuo Li, Yuechen Wu, Lei Ma, Xiaofei Xie, Yingfeng Chen, Changjie Fan

Research Collection School Of Computing and Information Systems

Software bug database and benchmark are the wheels of advancing automated software testing. In practice, real bugs often occur sparsely relative to the amount of software code, the extraction and curation of which are quite labor-intensive but can be essential to facilitate the innovation of testing techniques. Over the past decade, several milestones have been made to construct bug databases, pushing the progress of automated software testing research. However, up to the present, it still lacks a real bug database and benchmark for game software, making current game testing research mostly stagnant. The missing of bug database and framework greatly …

Multi-Level Cross-View Contrastive Learning For Knowledge-Aware Recommender System, Ding Zou, Wei Wei, Xian-Ling Mao, Ziyang Wang, Minghui Qiu, Feida Zhu, Xin Cao

Research Collection School Of Computing and Information Systems

Knowledge graph (KG) plays an increasingly important role in recommender systems. Recently, graph neural networks (GNNs) based model has gradually become the theme of knowledge-aware recommendation (KGR). However, there is a natural deficiency for GNN-based KGR models, that is, the sparse supervised signal problem, which may make their actual performance drop to some extent. Inspired by the recent success of contrastive learning in mining supervised signals from data itself, in this paper, we focus on exploring the contrastive learning in KG-aware recommendation and propose a novel multi-level cross-view contrastive learning mechanism, named MCCLK. Different from traditional contrastive learning methods which …

Enhancing Security Patch Identification By Capturing Structures In Commits, Bozhi Wu, Shangqing Liu, Ruitao Feng, Xiaofei Xie, Jingkai Siow, Shang-Wei Lin

Research Collection School Of Computing and Information Systems

With the rapid increasing number of open source software (OSS), the majority of the software vulnerabilities in the open source components are fixed silently, which leads to the deployed software that integrated them being unable to get a timely update. Hence, it is critical to design a security patch identification system to ensure the security of the utilized software. However, most of the existing works for security patch identification just consider the changed code and the commit message of a commit as a flat sequence of tokens with simple neural networks to learn its semantics, while the structure information is …

Early Rumor Detection Using Neural Hawkes Process With A New Benchmark Dataset, Fengzhu Zeng, Wei Gao

Research Collection School Of Computing and Information Systems

Little attention has been paid on EArly Rumor Detection (EARD), and EARD performance was evaluated inappropriately on a few datasets where the actual early-stage information is largely missing. To reverse such situation, we construct BEARD, a new Benchmark dataset for EARD, based on claims from fact-checking websites by trying to gather as many early relevant posts as possible. We also propose HEARD, a novel model based on neural Hawkes process for EARD, which can guide a generic rumor detection model to make timely, accurate and stable predictions. Experiments show that HEARD achieves effective EARD performance on two commonly used general …

Digbug: Pre/Post-Processing Operator Selection For Accurate Bug Localization, Kisub Kim, Sankalp Ghatpande, Kui Liu, Anil Koyuncu, Dongsun Kim, Tegawendé F. Bissyande, Jacques Klein, Yves Le Traon

Research Collection School Of Computing and Information Systems

Bug localization is a recurrent maintenance task in software development. It aims at identifying relevant code locations (e.g., code files) that must be inspected to fix bugs. When such bugs are reported by users, the localization process become often overwhelming as it is mostly a manual task due to incomplete and informal information (written in natural languages) available in bug reports. The research community has then invested in automated approaches, notably using Information Retrieval techniques. Unfortunately, reported performance in the literature is still limited for practical usage. Our key observation, after empirically investigating a large dataset of bug reports as …

Contours Of Virtual Enfreakment In Fighting Game Characters, Sercan Sengun, Peter Mawhorter, James Bowie-Wilson, Yusef Audeh, Haewoon Kwak, D. Fox Harrell

Research Collection School Of Computing and Information Systems

Characters in fighting videogames1 such as Street Fighter V and Tekken7 typically reveal a phenomenon that we define as virtual enfreakment: their bodies, costumes, and fighting styles are exaggerated (1) in a manner that emphasizes perceived exoticism and (2) to enable them to be easily visually and conceptually distinguishable from one another. Here, using both quantitative and qualitative methods, including crowd-sourced surveys and analyses of game mechanics, we report on the contours of virtual enfreakment in those games. We specifically examine differences in character design across gender, national-origin, and skin-color lines. Disappointingly but not surprisingly, we find racism and sexism …

Designing Flipped Learning Activities For Beginner Programming Course, Benjamin Gan, Eng Lieh Ouh

Research Collection School Of Computing and Information Systems

This study focuses on designing flipped classroom learning activities across pre-class problem-based exercises; with in-class active discussions and practical problem-solving sessions; and follow up with postclass problem-based labs and assessments. We evaluate the effectiveness of our learning activities based on student surveys, course feedback, grades, and teacher feedback for a beginner programming course with non-IS students. We describe detail programming learning activities with comparisons to existing practices based on related work. Our findings are that majority of students (86%) agreed with flipped classroom, but teachers should be aware of the 14% who disagreed and cater for them. Teachers should avoid …