Digital Commons Network^™

Deployment Policies To Reliably Maintain And Maximize Expected Coverage In A Wireless Sensor Network, Nicholas T. Boardman

Graduate Theses and Dissertations

The long-term operation of a wireless sensor network (WSN) requires the deployment of new sensors over time to restore any loss in network coverage and communication ability resulting from sensor failures. Over the course of several deployment actions it is important to consider the cost of maintaining the WSN in addition to any desired performance measures such as coverage, connectivity, or reliability. The resulting problem formulation is approached first through a time-based deployment model in which the network is restored to a fixed size at periodic time intervals. The network destruction spectrum (D-spectrum) has been introduced to estimate reliability and …

The Characterization Of Angiopoietin-Like Protein 4 Overexpression In Triple Negative Breast Cancer, Jodi Simeon

Graduate Theses and Dissertations

Triple Negative Breast Cancer (TNBC) is highly invasive and metastatic with approximately 15% of patients developing liver metastases. The primary treatment of metastatic TNBC is chemotherapy, however, there is an increased chance of resistance to this therapeutic technique. If Breast Cancer Liver Metastasis (BCLM) is left untreated most patients survive only 4 to 8 months with a very rare 5-year survival. Therefore, it is imperative to analyze markers and molecular pathways that TNBC cells use to progress, invade, and metastasize to the liver. The aim of this study was to examine the overexpression of angiopoietin-like 4 (ANGPTL4) in TNBC cells …

Enabling The “Easy Button” For Broad, Parallel Optimization Of Functions Evaluated By Simulation, Andrew Gibson

Graduate Theses and Dissertations

Java Optimization by Simulation (JOBS) is presented: an open-source, object-oriented Java library designed to enable the study, research, and use of optimization for models evaluated by simulation. JOBS includes several novel design features that make it easy for a simulation modeler, without extensive expertise in optimization or parallel computation, to define an optimization model with deterministic and/or stochastic constraints, choose one or more metaheuristics to solve it and run, using massively parallel function evaluation to reduce wall-clock times.

JOBS is supported by a new language independent, application programming interface (API) for remote simulation model evaluation and a serverless computing environment …

Are Rice Markets In Bangladesh Efficiently Pricing Rice Based On Quality? An Empirical Assessment, Indrani Saha

Graduate Theses and Dissertations

Rice is an important staple for more than half of the world’s population and is the main staple in Bangladesh, accounting for 65 percent to 70 percent of the daily calorie intake. The importance of rice consumption and the high level of food insecurity in Bangladesh highlights the importance of having markets that efficiently price rice according to consumer preferences. This study aims to assess how effectively rice prices in Bangladesh are reflective of rice quality. More specifically, we estimate how the rice market is currently pricing selected rice quality attributes, such as broken percentage, chalk percentage, kernel size and …

A Time-Course Characterization Of Muscle Function And Mitochondrial Markers During Colorectal Cancer-Induced Cachexia In Tumor-Bearing Male Mice, Ana Cabrera Ayuso

Graduate Theses and Dissertations

Cachexia is a multisystemic and multifactorial syndrome prevalent in cancer patients. It is clinically defined by involuntary loss of >5% weight in a six-month window, despite nutritional interventions. A negative energy balance characterizes cancer cachexia (CC), it is associated with weakness and fatigue in skeletal muscle. Impaired muscle function is associated with lower quality of life in cancer patients. Defects in mitochondrial function are strongly associated with muscle wasting. This study explored muscular contractile function and mitochondrial quality control (MQC) markers in soleus, gastrocnemius, and tibialis anterior (TA) muscles of C26-induced male tumor-bearing mice during a 25-day time course. It …

Unintended Consequences Of Public Policy And Government Regulation On Supply Chain Structure, Conduct, And Performance, Jonathan Phares

Graduate Theses and Dissertations

Supply chains, and the firms within them, change their behaviors in response to industry conditions so they can provide efficiency, effectiveness, strategic enablement, and customer utility. Social and economic policies enacted to promote social welfare by correcting market failures can alter these conditions. While these policies may serve their intended purposes, they may also create unintended consequences that may make managing logistics, operations, and supply chains more challenging. This dissertation contributes to the nascent body of knowledge concerning the intended and unintended consequences of policy on supply chain management by examining three unique contextual settings using different methodologies and levels …

The Co-Regulatory Effects Of Emotionally Focused Therapy, Julia Conroy

Graduate Theses and Dissertations

Mental health literature emphasizes the necessity of expanding emotional regulation to improve symptomology of a variety of mental health disorders. Coregulatory experiences have been shown to expand individual emotional regulation and are more likely in relationships with secure attachment. Emotionally Focused Therapy (EFT) is focused on developing secure attachment between partners. This study examined the coregulatory effects of EFT with a single couple over the course of couples’ counseling. The participating couple received eight couples’ counseling sessions from a clinician who is a certified EFT trainer, supervisor, and therapist while having their heart rate, electrodermal activity, and skin temperature taken …

Towards A Large-Scale Intelligent Mobile-Argumentation And Discovering Arguments, Controversial Topics And Topic-Oriented Focal Sets In Cyber-Argumentation, Najla Althuniyan

Graduate Theses and Dissertations

User-generated content (UGC) platforms host different forms of information, such as audio, video, pictures, and text. They have many online applications, such as social media, blogs, photo and video sharing, customer reviews, debate, and deliberation platforms. Usually, the content of these platforms is provided and consumed by users. Most of these platforms, mainly social media and blogs, are often used for online discussion. These platforms offer tools for users to share and express opinions. Commonly, people from different backgrounds and origins discuss opinions about various issues over the Internet. Furthermore, discussions among users contain substantial information from which knowledge about …

Audit Firms’ Response To Audit Failures: Evidence From Partner Resource Reallocation, Elizabeth Cowle

Graduate Theses and Dissertations

I investigate whether audit firms reallocate partner resources following restatement announcements and, consequently, whether a supply-side response is beneficial in mitigating the previously documented implications of realized audit failures. I find a positive association between prior period restatement announcements and the year-over-year percentage change in the number of engagement partners allocated to a local audit office. Further analysis suggests that a supply-side response is beneficial in mitigating the persistence of low-quality audits and lost market share. However, I also find some evidence suggesting that the reallocation of partner resources can be detrimental to audit quality at offices from which partners …

Geolocation Of Monitoring Wells Using Small Unmanned Aircraft Systems, Joel Deyoung

Graduate Theses and Dissertations

Groundwater monitoring wells are commonly installed on a property as part of an environmental investigation to observe hydrological subsurface conditions, facilitate the collection of groundwater samples, and predict the flow of groundwater across a site. In addition to their installation, monitoring wells should be surveyed or mapped as accurately as possible. Traditional surveying techniques have employed the use of global navigation satellite systems (GNSS) technologies or other surveying equipment. A common surveying approach is to use real-time kinematic (RTK) GNSS to accurately measure the coordinates of each monitoring well on the site.In recent years, drones, or small unmanned aircraft systems …

Interpolation And Sampling In Analytic Tent Spaces, Caleb Parks

Graduate Theses and Dissertations

Introduced by Coifman, Meyer, and Stein, the tent spaces have seen wide applications in harmonic analysis. Their analytic cousins have seen some applications involving the derivatives of Hardy space functions. Moreover, the tent spaces have been a recent focus of research. We introduce the concept of interpolating and sampling sequences for analytic tent spaces analogously to the same concepts for Bergman spaces. We then characterize such sequences in terms of Seip's upper and lower uniform density. We accomplish this by exploiting a kind of Mobius invariance for the tent spaces.

Experimental And Analysis Of Electromagnetic Characterization Of Biological And Non-Biological Materials In Microwave, Millimeter-Wave, And Terahertz Frequency Bands, Nagma Vohra

Graduate Theses and Dissertations

The goal of this research is to characterize the electromagnetic properties of biological and non-biological materials at terahertz (THz), millimeter-wave, and microwave frequency bands. The biological specimens are measured using the THz imaging and spectroscopy system, whereas the non-biological materials are measured using the microwave and millimeter-wave free-space system. These facilities are located in the Engineering Research Center at the University of Arkansas. The THz imaging system (TPS 3000) uses a Ti-Sapphire laser directed on the photoconductive antennas to generate a THz time domain pulse. Upon using the Fourier Transform, the spectrum of the pulsed THz signal includes frequencies from …

Use Of The Igbt Module In The Active Region To Design A High Current Active Filter, Jorge F. Galarraga

Graduate Theses and Dissertations

Particle accelerators require high-precision magnetic fields on the order or 100ppm or less. This implies that the precision of the associated electrical current in the electromagnet that generates these fields should be smaller than 100ppm. However, conventional switching power supplies cannot offer this precision due to the frequency limitation of the switches. This research considers the use of power electronics devices operating in a linear as an alternative solution to meet the requirements of particle accelerator electromagnets.

This thesis presents the study of an insulated-gate bipolar transistor (IGBT) driver using a new control method that linearizes the IGBT’s collector-emitter voltage …

Design And Development Of Techniques To Ensure Integrity In Fog Computing Based Databases, Abdulwahab Fahad S. Alazeb

Graduate Theses and Dissertations

The advancement of information technology in coming years will bring significant changes to the way sensitive data is processed. But the volume of generated data is rapidly growing worldwide. Technologies such as cloud computing, fog computing, and the Internet of things (IoT) will offer business service providers and consumers opportunities to obtain effective and efficient services as well as enhance their experiences and services; increased availability and higher-quality services via real-time data processing augment the potential for technology to add value to everyday experiences. This improves human life quality and easiness. As promising as these technological innovations, they are prone …

Exploring Differences In Mathematical Creative Potential And Problem-Posing In Gifted And Non-Gifted Middle School Students, Aishah Ahmed Alzahrani

Graduate Theses and Dissertations

The purpose of this study was to investigate the link between students’ Mathematical Creative Potential (MCP) and giftedness by analyzing their abilities to pose mathematical problems. The participants included 260 gifted and non-gifted students from the 7th and 8th grades, representing four schools and four school districts in Northwest Arkansas. The study developed the Mathematical Creative Potential Scale (MCPS) to measure participant MCP. The MCPS is based on a divergent-thinking technique consisting of five free-structured and semi-structured situations. Students’ plausible problems were scored based on three dimensions of creativity: fluency, flexibility, and originality. This study found that there were statistically …

Overcoming Learning Anxiety In Workplace Learning: A Study Of Best Practices And Training Accommodations That Improve Workplace Learning, Ann-Marie Piscitelli

Graduate Theses and Dissertations

Anxiety disorders are the most common mental illness in the U.S. and affect 40 million adults, or 18.1% of the population each year. Anxiety plays an essential role in encouraging productive learning outcomes; however, uncontrolled anxiety could result in heightened emotions that create barriers to learning. Employees who have anxiety disorders may experience these barriers to learning when in traditional training programs and may require support or accommodations to boost their unique learning needs for development in the workplace. Human Resource Development (HRD) professionals’ challenge is how best to intervene when an employee exhibits behaviors of learning anxiety to nurture …

Promoting Diversity In Academic Research Communities Through Multivariate Expert Recommendation, Omar Salman

Graduate Theses and Dissertations

Expert recommendation is the process of identifying individuals who have the appropriate knowledge and skills to achieve a specific task. It has been widely used in the educational environment mainly in the hiring process, paper-reviewer assignment, and assembling conference program committees. In this research, we highlight the problem of diversity and fair representation of underrepresented groups in expertise recommendation, factors that current expertise recommendation systems rarely consider. We introduce a novel way to model experts in academia by considering demographic attributes in addition to skills. We use the h-index score to quantify skills for a researcher and we identify five …

A Radiographic Investigation Of Anthropometrics, Neck Posture, And Neck Strength In Individuals With Enlarged External Occipital Protuberances, Caleb Burruss

Graduate Theses and Dissertations

Overview: Enlarged external occipital protuberances (EEOPs) are found in 41% of young adults. These EEOPs have the potential to lead to pain throughout life and possibly surgery. Little is known of the pathophysiology or characteristics that could lead to these EEOPs. Purpose: The purpose of this study is to use radiographic measurements to investigate how anthropometrics, neck posture and neck strength in flexion and extension differ between those with and without an EEOP. Methods: 80 radiographs from three different studies were digitized and the marking of landmarks performed in ImageJ. The cut-off for an EEOP was established as any EOP …

A Portable Point-Of-Care Device Using Joule Heating And Latent Energy Storage For The Temperature Regulation Of Isothermal Nucleic Acid Amplification Tests, Aubrey Lynn Schultz

Graduate Theses and Dissertations

Accurate and early diagnosis of infectious diseases extremely important. Rapid diagnosis allows for effective treatment and increases the chance for recovery without complications. Additionally, the ability to test the populace frequently, swiftly, and affordably significantly aids in containing wide-scale outbreaks. In terms of specificity and sensitivity, nucleic acid amplification tests (NAAT) are one of the best options for diagnosing infectious diseases. Isothermal NAATS present a unique opportunity to create diagnostic tests deployed at a Point-of-Care (POC) level. Specifically, loop-mediated isothermal amplification (LAMP) and recombinase polymerase amplification (RPA) have the potential to deliver reliable POC diagnostics in low-resource settings. When designing …

Efficiently Estimating Survival Signature And Two-Terminal Reliability Of Heterogeneous Networks Through Multi-Objective Optimization, Daniel Bruno Lopes Da Silva

Graduate Theses and Dissertations

The two-terminal reliability problem is a classical reliability problem with applications in wired and wireless communication networks, electronic circuit design, computer networks, and electrical power distribution, among other systems. However, the two-terminal reliability problem is among the hardest combinatorial problems and is intractable for large, complex networks. Several exact methods to solve the two-terminal reliability problem have been proposed since the 1960s, but they have exponential time complexity in general. Hence, practical studies involving large network-type systems resort to approximation methods to estimate the system's reliability. One attractive approach for quantifying the reliability of complex systems is to use signatures, …

Assessing Impacts Of Winter-Hay Feeding On Soil And Forage Nutrient Dynamics In A Rotationally-Grazed Pasture System In Arkansas, Lawrence Gordon Berry Iv

Graduate Theses and Dissertations

More than 38 % of United States’ rural land area was used for grazing (i.e., pastureland or rangeland) ruminant animals in 2017, constituting the largest private land use group. The expansive nature of these lands means that grazing and pasture management decisions have potential to impact water quality as well as profit margins. As a result, beef producers are under increased pressure from economic and environmental standpoints to limit application of nutrients beyond those required to grow the forage needed for animal consumption. At the same time, a large amount of nutrients is recycled back to pasture systems directly from …

Using Transcendental Phenomenology To Explore Elementary Teachers’ Experiences With Struggling Readers During The Social Restrictions Precipitated By The Covid-19 Pandemic, Wyann C. Stanton

Graduate Theses and Dissertations

This study provides a window into the experiences of elementary teachers with their struggling readers during the largest world-wide interruption to education that has ever been seen. This study gives insight to educational leaders and educators as they assist their struggling readers in rebounding from the disruption to school caused by the COVID-19 pandemic and as they work to improve the quality of schooling for struggling readers. Since the beginning of the pandemic, there had been a growing body of educational literature in pandemic-related information, practice, and research. Yet, there was a need to bring to light the phenomenon of …

Automated Privacy Protection For Mobile Device Users And Bystanders In Public Spaces, David Darling

Graduate Theses and Dissertations

As smartphones have gained popularity over recent years, they have provided usersconvenient access to services and integrated sensors that were previously only available through larger, stationary computing devices. This trend of ubiquitous, mobile devices provides unparalleled convenience and productivity for users who wish to perform everyday actions such as taking photos, participating in social media, reading emails, or checking online banking transactions. However, the increasing use of mobile devices in public spaces by users has negative implications for their own privacy and, in some cases, that of bystanders around them.

Specifically, digital photography trends in public have negative implications for …

On The Epistemic Significance Of Expert Conversion, Dax R. Bennington

Graduate Theses and Dissertations

Much of our knowledge of the world depends on the testimony of experts. Experts sometimes change their minds and disagree with each other. What ought a novice do when an expert changes their mind? This dissertation provides an account of when expert conversion is epistemically significant and how the novice ought to rationally defer to expert conversion. In answering when expert conversion is epistemically significant, I provide a diagnostic tool that emphasizes that epistemically significant expert conversion seems to be evidence-based and that there is an absence of cognitive biases on the part of the converting expert. In answering how …

Fabrication And Characterization Of Photodetector Devices Based On Nanostructured Materials: Graphene And Colloidal Nanocrystals, Wafaa Gebril

Graduate Theses and Dissertations

Photodetectors are devices that capture light signals and convert them into electrical signals. High performance photodetectors are in demand in a variety of applications, such as optical communication, security, and environmental monitoring. Among many appealing nanomaterials for novel photodetection devices, graphene and semiconductor colloidal nanocrystals are promising candidates because of their desirable and unique properties compared to conventional materials.

Photodetector devices based on different types of nanostructured materials including graphene and colloidal nanocrystals were investigated. First, graphene layers were mechanically exfoliated and characterized for device fabrication. Self-powered few layers graphene phototransistors were studied. At zero drain voltage bias and room …

Grid Strength Assessment Trough Q-V Modal Analysis And Maximum Loadability Of A Wind-Dominated Power System Using P-Q Regions, Pierre Obed Dorile

Graduate Theses and Dissertations

Climate change is a menace to the existence of the world and policymakers are trying totackle this phenomenon by deploying large-scale wind farms into their grids. Among them, wind energy shows a promising future to substitute the traditional power plants. However, the deployment of these wind farms into the grid is not a panacea that does not pose any challenges to the grid operators. Keeping the power system voltage stable while considering the strength of the transmission grid is among the major challenges facing by the transmission system operators. Amid normal operation and fault conditions, wind farms should help the …

The First Sign: Detecting Future Financial Fraud From The Ipo Prospectus, Lisa Spadaccini Anderson

Graduate Theses and Dissertations

In this study, I examine whether it is possible to predict future financial statement fraud using disclosure content prior to the fraud. Specifically, I employ a machine learning algorithm to construct a unique measure based on the lexical cues embedded within a firm’s first public disclosure, the Management’s Discussion and Analysis section of the S-1 filing, during the Initial Public Offering process. I use this measure to predict whether a firm that is not already committing fraud will commit fraud within five years of the Initial Public Offering (IPO) that results in an Accounting or Enforcement Release (AAER). I find …

Combating Conspiracy Theories: An Attitudes-Based Approach, Marie Altgilbers

Graduate Theses and Dissertations

The prevalence of conspiracy theories is a topic of increasing concern among researchers. Much of the research in this area has been focused on why people endorse conspiracy theories, and relatively little attention has been paid to how they may be mitigated. What research has been done focused primarily on interventions with arguments based in cognitive, fact-based appeals, with mixed success. The present research draws on findings from the attitudes and persuasion literature to test the hypothesis that conspiracy theory endorsement is more effectively reduced by affectively-based arguments than by cognitively-based arguments. Two affectively-based interventions were tested against a cognitively-based …

Development Of A Reference Design For Intrusion Detection Using Neural Networks For A Smart Inverter, Ammar Mohammad Khan

Graduate Theses and Dissertations

The purpose of this thesis is to develop a reference design for a base level implementation of an intrusion detection module using artificial neural networks that is deployed onto an inverter and runs on live data for cybersecurity purposes, leveraging the latest deep learning algorithms and tools. Cybersecurity in the smart grid industry focuses on maintaining optimal standards of security in the system and a key component of this is being able to detect cyberattacks. Although researchers and engineers aim to design such devices with embedded security, attacks can and do still occur. The foundation for eventually mitigating these attacks …

Made Of Water, Covered In Mud, Nicole Norman

Graduate Theses and Dissertations

My fixation on water as metaphor is a product of my cosmic design; Scorpio sun, Pisces moon, Pisces rising. I am made of water, begging to be held. Anything liquid has this same desire. I use my art practice to examine the fluidity of physical and digital spaces; how they transform almost constantly. This is only possible through the use of containers that give form to abstract ideas and make them easier to drink (read: digest). Containers can vary in size and shape, but their purpose remains the same. A drinking glass, a swimming pool, a creek bed. These are …