Digital Commons Network^™

Investigation Of Heat Exchanger Effectiveness Using A Surface Coating Technology, Allen Duffy

Graduate Theses, Dissertations, and Problem Reports (ETD)

Diesel engine manufacturers continue to improve engine performance through increased thermal efficiency and reduced regulated emissions. The aftercooler located between the turbocharger air outlet and intake manifold experiences a wide range of operating conditions. Improving the heat transfer characteristics in the aftercooler can lead towards improved engine performance through increased charge air density. A surface coating has been proposed to enhance the heat transfer characteristics for a marine-based application on the water - side of the heat exchanger. To evaluate the efficacy of the coating, the rate of heat transfer with and without the coating was quantified in a controlled …

Beneath The Gypsum Dunes: Cenozoic History Of Wind And Water From A Core Drilled At White Sands, New Mexico, Jackson Bentley Jakeway

Graduate Theses, Dissertations, and Problem Reports (ETD)

White Sands, New Mexico is the largest gypsum dune field on planet Earth, the result of reworking of gypsum deposits. The dunes have been well studied, but the Cenozoic history preceding the formation of the dune field has been poorly studied. A core drilled to a depth of 192 ft (58.5 m) beneath the modern dune field contains deposits from saline lakes, sandflats, perennial freshwater lakes, perennial brackish to saline lakes, and saline mudflats.

The core is composed of bottom-growth bedded gypsum, gypsum sandstone and siltstone, mixed siliciclastic-gypsum sandstones and siltstones, laminated siliciclastic mudstones, gypsum mudstones, and carbonate mudstones. Bottom-growth …

Immunity-Based Framework For Autonomous Flight In Gps-Challenged Environment, Mohanad Al Nuaimi

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this research, the artificial immune system (AIS) paradigm is used for the development of a conceptual framework for autonomous flight when vehicle position and velocity are not available from direct sources such as the global navigation satellite systems or external landmarks and systems. The AIS is expected to provide corrections of velocity and position estimations that are only based on the outputs of onboard inertial measurement units (IMU). The AIS comprises sets of artificial memory cells that simulate the function of memory T- and B-cells in the biological immune system of vertebrates. The innate immune system uses information about …

Copper-Catalyzed Regioselective Boracarboxylation Of Vinyl Arenes: Catalytic Efficiency And Synthetic Utility, Trina M. Perrone

Graduate Theses, Dissertations, and Problem Reports (ETD)

Hetero(element) carboxylation is an appealing transformation that involves the installation of CO2 and another hetero(element) in one step. This transition metal-catalyzed one-pot synthesis provides a route to achieve highly functionalized carboxylic acid products with an abundant and cheap C1 feedstock. This difunctionalization also avoids the use of reactive metal hydride species, which is a prominent limitation of hydrocarboxylation chemistry. A copper-catalyzed regioselective boracarboxylation of vinyl arenes has been developed to access pharmaceutically relevant β-boryl-α-aryl propionic acid products. One drawback of this reaction is the necessity for high catalyst loading to achieve catalytic turnover. To circumvent this issue, the reduction of …

Novel Computational Methods For Catalytic Applications, Gihan Uthpala Panapitiya

Graduate Theses, Dissertations, and Problem Reports (ETD)

Thiolate protected nanoclusters gold nanoparticles are gaining interest of many researchers due to their promising applications in a variety of fields the development of synthesizing techniques capable of producing atomically precise nanoclusters with high purity. Au₂₅(SR)₁₈ is one of the widely studied nanoclsuters due its remarkable stability. In this first part of this study, we explore the structural, electronic and catalytic properties of bimetallic Au_25−xAg_x(SR)₁₈ (for x = 6, 7, 8). Due to the combinatorial enormity of the total number of possible alloyed isomers, we choose a randomly selected subset corresponding to …

Efficacy Of Cognitive Training Intervention With A Coaching Component On Attention And Response Control In Emerging Adults, Thomas Craig Foster Jr

Graduate Theses, Dissertations, and Problem Reports (ETD)

Cognitive training, a nonpharmacological intervention for attention and learning-related difficulties, is a promising treatment option for emerging adults. The aim of this study was to explore the efficacy of a cognitive training program with a coaching component on measures of attention and response control in university students. Between 2014 and 2017, 39 students with reported attention concerns engaged in a cognitive training program over ten weeks (20 sessions) at a university counseling center. Differences in participants’ attention and response control as measured by the IVA-2 Continuous Performance Test (CPT) were evaluated before and after the intervention. Demographic data, including clinician …

Scaling Analysis And Experimental Investigation Of A Rotating Detonation Engine, David Thomas Billups

Graduate Theses, Dissertations, and Problem Reports (ETD)

Pressure gain combustion (PGC) technologies, specifically rotating detonation engines (RDEs), are poised to provide the next big leap in gas turbine engine advancement, significantly increasing the thermal. RDEs make use of thermodynamic advantages of isochoric as opposed to isobaric combustion. Theorized to increase thermal efficiency by up to 7% [1], the RDE would have significant impact on reducing anthropogenic carbon emissions. In addition to efficiency gains, the RDE also provides mechanical simplicity and reduced size advantages compared to it’s traditional counterparts and PGC competition.

The United States (U.S.) Department of Energy (DOE) National Energy Technology Laboratory (NETL) maintains and operates …

Pharmaceutical Scheduling Using Simulated Annealing And Steepest Descent Method, Bryant Jamison Spencer

Graduate Theses, Dissertations, and Problem Reports (ETD)

In the pharmaceutical manufacturing world, a deadline could be the difference between losing a multimillion-dollar contract or extending it. This, among many other reasons, is why good scheduling methods are vital. This problem report addresses Flexible Flowshop (FF) scheduling using Simulated Annealing (SA) in conjunction with the Steepest Descent heuristic (SD).

FF is a generalized version of the flowshop problem, where each product goes through S number of stages, where each stage has M number of machines. As opposed to a normal flowshop problem, all ‘jobs’ do not have to flow in the same sequence from stage to stage. The …

Deformation Correlations And Machine Learning: Microstructural Inference And Crystal Plasticity Predictions, Michail Tzimas

Graduate Theses, Dissertations, and Problem Reports (ETD)

The present thesis makes a connection between spatially resolved strain correlations and material processing history. Such correlations can be used to infer and classify prior deformation history of a sample at various strain levels with the use of Machine Learning approaches. A simple and concrete example of uniaxially compressed crystalline thin films of various sizes, generated by two-dimensional discrete dislocation plasticity simulations is examined. At the nanoscale, thin films exhibit yield-strength size effects with noisy mechanical responses which create an interesting challenge for the application of Machine Learning techniques. Moreover, this thesis demonstrates the prediction of the average mechanical responses …

Using Machine Learning And Traditional Statistics To Explore Retention And Knowledge Structure In Stem With An Emphasis On Physics, Cabot Alexander Zabriskie

Graduate Theses, Dissertations, and Problem Reports (ETD)

Retention of Science, Technology, Engineering, and Mathematics (STEM) students is a serious problem as STEM graduation rates continue to lag the growing demand for the skills taught by these degree programs. Critical to fixing this “leaky pipeline” is investment in improving retention in the first two years of college study and increasing and maintaining the interest of K-12 students in STEM. This thesis will address this in three parts. The first is through evaluation of conceptual tests used to evaluate course improvements to determine the structure student knowledge measured by them. The second part uses machine learning to construct early …

Reconciling The Dissonance Between Historic Preservation And Virtual Reality Through A Place-Based Virtual Heritage System., Danny J. Bonenberger

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study explores a problematic disconnect associated with virtual heritage and the immersive 3D computer modeling of cultural heritage. The products of virtual heritage often fail to adhere to long-standing principles and recent international conventions associated with historic preservation, heritage recording, designation, and interpretation. By drawing upon the geographic concepts of space, landscape, and place, along with advances in Geographic Information Systems, first-person serious games, and head-mounted Virtual Reality platforms this study envisions, designs, implements, and evaluates a virtual heritage system that seeks to reconcile the dissonance between Virtual Reality and historic preservation. Finally, the dissertation examines the contributions and …

Factors Influencing Survival, Productivity, And Population Growth Of Eastern Wild Turkeys In Northeastern South Dakota, Reina M. Tyl

Graduate Theses, Dissertations, and Problem Reports (ETD)

The population of eastern wild turkeys in northeastern South Dakota appeared to be expanding soon after reintroduction in the 1990s, however, recent harvest trends suggest declining abundance in the region. Spring turkey hunting expenditures are projected to be around $6.5 million in South Dakota, with about $3 million of those expenditures occurring within the northeastern prairie region. However, the number of birds harvested during the spring prairie firearm season has been declining since 2010. Due to concerns about a declining population, the autumn hunting season was closed in 2014. The cause of the apparent decline is unclear. Updated demographic information …

Infinite Matroids And Transfinite Sequences, Martin Andrew Storm

Graduate Theses, Dissertations, and Problem Reports (ETD)

A matroid is a pair M = (E,I) where E is a set and I is a set of subsets of E that are called independent, echoing the notion of linear independence. One of the leading open problems in infinite matroid theory is the Matroid Intersection Conjecture by Nash-Williams which is a generalization of Hall’s Theorem. In [31] Jerzy Wojciechowski introduced µ- admissibility for pairs of matroids on the same ground set and showed that it is a necessary condition for the existence of a matching. A pair of matroids (M,W) with common ground set E is µ-admissible if a …

The Impact Of Using Selected Art Therapy Approaches On Students Diagnosed On The Autism Spectrum (As) Or With Behavioral Disabilities (Bd) In An Elementary School Art Classroom., Amie Dawn Perriello

Graduate Theses, Dissertations, and Problem Reports (ETD)

Students with autism and behavior disorders frequently have a difficult time communicating with their teachers and peers. Art can serve as a vehicle for communication while supporting strengths and encouraging self-esteem. Yet few art teachers have the specialized training needed to work with students on the spectrum, and we are often times left to our own intuition and devices on how to deal with these students. These students deserve greater individualized education, yet this can present a unique challenge to any classroom art teacher who does not have the training to deal with students who come from these special populations. …

Intelligent Malware Detection Using File-To-File Relations And Enhancing Its Security Against Adversarial Attacks, Lingwei Chen

Graduate Theses, Dissertations, and Problem Reports (ETD)

With computing devices and the Internet being indispensable in people's everyday life, malware has posed serious threats to their security, making its detection of utmost concern. To protect legitimate users from the evolving malware attacks, machine learning-based systems have been successfully deployed and offer unparalleled flexibility in automatic malware detection. In most of these systems, resting on the analysis of different content-based features either statically or dynamically extracted from the file samples, various kinds of classifiers are constructed to detect malware. However, besides content-based features, file-to-file relations, such as file co-existence, can provide valuable information in malware detection and make …

Multimodal Approach For Malware Detection, Jarilyn M. Hernandez Jimenez

Graduate Theses, Dissertations, and Problem Reports (ETD)

Although malware detection is a very active area of research, few works were focused on using physical properties (e.g., power consumption) and multimodal features for malware detection. We designed an experimental testbed that allowed us to run samples of malware and non-malicious software applications and to collect power consumption, network traffic, and system logs data, and subsequently to extract dynamic behavioral-based features. We also extracted code-based static features of both malware and non-malicious software applications. These features were used for malware detection based on: feature level fusion using power consumption and network traffic data, feature level fusion using network traffic …

Analyzing Satisfiability And Refutability In Selected Constraint Systems, Piotr Jerzy Wojciechowski

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation is concerned with the satisfiability and refutability problems for several constraint systems. We examine both Boolean constraint systems, in which each variable is limited to the values true and false, and polyhedral constraint systems, in which each variable is limited to the set of real numbers R in the case of linear polyhedral systems or the set of integers Z in the case of integer polyhedral systems. An important aspect of our research is that we focus on providing certificates. That is, we provide satisfying assignments or easily checkable proofs of infeasibility depending on whether the instance …

Explanatory And Causality Analysis In Software Engineering, Yasser Ali Alshehri

Graduate Theses, Dissertations, and Problem Reports (ETD)

Software fault proneness and software development efforts are two key areas of software engineering. Improving them will significantly reduce the cost and promote good planning and practice in developing and managing software projects. Traditionally, studies of software fault proneness and software development efforts were focused on analysis and prediction, which can help to answer questions like `when’ and `where’. The focus of this dissertation is on explanatory and causality studies that address questions like `why’ and `how’.

First, we applied a case-control study to explain software fault proneness. We found that Bugfixes (Prerelease bugs), Developers, Code Churn, and Age of …

Implementation Of A State-Of-The-Art Gnss Receiver Autonomous Integrity Monitoring Technique, Shannen Daly

Graduate Theses, Dissertations, and Problem Reports (ETD)

No abstract provided.

Dynamic Modeling And Advanced Control Of A Refinery Hydrocracker Process, Christian Ayafor

Graduate Theses, Dissertations, and Problem Reports (ETD)

No abstract provided.

Development Of Hydraulic Models, Mass Transfer Models, And Dynamic Models Of Solvent-Based Carbon Capture Processes With Uncertainty Quantification And Validation With Pilot Plant Data, Anderson Soares Chinen

Graduate Theses, Dissertations, and Problem Reports (ETD)

To accelerate the development and commercial deployment of CO2 capture technologies, computational tools and models are being developed under the auspices of the U.S. Department of Energy's Carbon Capture Simulation Initiative (CCSI). The CCSI process modeling team was tasked with developing a "gold-standard" model that will serve as a definitive reference for benchmarking the performance of solvent-based CO2 capture systems under steady-state and dynamic conditions over a large operating-range. The main three areas that this work focused on are: development of the hydrodynamic and mass transfer submodels for a monoethanolamine (MEA) solvent system, uncertainty quantification of these submodels, development of …

Passive Wireless Temperature Sensing In Extreme Harsh Environments, Michael R. Comparetto

Graduate Theses, Dissertations, and Problem Reports (ETD)

As the technology in the elds of aerospace and the US power generation industry advances, there is a critical need for new extreme high temperature sensing / monitoring technologies to replace the current out-of-date sensing systems. As the operating temperatures of these jet and turbine engines continue to rise over 1000 C, it is vitally important to monitor the extreme high temperatures in these engines for system health monitoring and to achieve greater engine eciencies. We propose a new passive wireless temperature sensor capable of sensing these extreme high temperatures. The sensor uses an LC resonance circuit to measure the …

Electrophoretic Characterization Of Carbon Nanotubes: Elucidation Of Surface Functionalization And Interaction, Tyler A. Davis

Graduate Theses, Dissertations, and Problem Reports (ETD)

Carboxylation of multiwall carbon nanotubes is used to enhance physical properties by improving dispersion, increasing compatibility and providing an interface for surface interaction. Accurate characterization of the multiwall carbon nanotubes surface is important as multiple applications depend on controlled functionalization. This dissertation is based on research that led to the adaption, validation and application of a capillary electrophoresis method for characterization of surface modification and interaction of carboxylated multiwall carbon nanotubes. The affinity based method uses electrostatic interaction of a selective peptide probe (WRWWWW) with multiwall carbon nanotubes to determine the degree of carboxylation. A 20% RSD in method reproducibility …

Canal Transportation After Instrumentation Utilizing Different Endodontic Access Design; A Comparative Study With Micro-Ct., Travis Moore

Graduate Theses, Dissertations, and Problem Reports (ETD)

Introduction Access cavity design is known to affect theefficiency of instrumentation. Canal transportation occurs primarily in the apical region and to the outside of curvature when dentin is removed in a single direction. The goal of all cleaning and shaping procedures is to preserve the original root canal anatomy while removing sufficient amounts of injured pulp tissue, microorganisms, toxins and instrumentation byproducts. It is understood that the desired shape of the finished root canal is a continuous tapering funnel from the coronal to the apex. The aim of this study is to construct detailed three-dimensional images of root canal systems …

Predicting Frac Hits Using Artificial Intelligence; Application In Marcellus Shale, Ryan Tyree

Graduate Theses, Dissertations, and Problem Reports (ETD)

This work introduces a process of using AI neural networks, for analyzing complex datasets, in order to achieve a higher prediction accuracy in regards to frac hits, at the individual stage level, in the Marcellus Shale when compared to traditional linear methods.;We examined 63 producing wells (parent) along with 79 completed wells (child) to determine the best predictors for accurate frac hit predictions. Our dataset consists of 959 records with 77 predictors and a single binary output (YES or NO) for a frac hit occurrence. Linear methods make analyzing these 77 predictors, along with their interactions, difficult. Neural networks, specifically …

Integrating Microscale Enzyme And Lectin Reactions Using Nanogel Assisted Capillary Electrophoresis, Srikanth Gattu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Protein glycosylation is one of the most prevalent post-translational modifications which plays an important role in determining the structure, stability, and function of proteins. Changes in glycosylation patterns are a hallmark of cancer and other diseases. Characterizing glycosylation is difficult because these structures vary in their linkage and monomer sequence, which gives rise to vast microheterogenity that could affect the function of the molecule. A novel method using capillary gel electrophoresis by integrating microscale enzymes and lectin reactions in the capillary was developed to verify glycan structure by analyzing monosaccharides. Capillary electrophoresis (CE) improves upon conventional methods of glycan structure …

Resilience Modeling Of Surface Transportation System In Mixed Traffic Environment, Shofiq Ahmed

Graduate Theses, Dissertations, and Problem Reports (ETD)

Large-scale natural disasters challenge the resilience of surface transportation system. The objective of this research was to develop a resilience model of surface transportation system in mixed-traffic environment considering varying Connected and Automated Vehicle (CAV) penetration scenarios. As deployment of CAVs are expected to improve traffic operations, a resilience model was developed in this research to evaluate the resilience performance of a transportation system with several CAV penetration levels (0%, 25%, 50%, 75% and 100%) for a given budget and recovery time. The proposed resilience quantification model was applied on a roadway network considering several disaster scenarios. The network capacity …

Inclusion Of 9 Mm Firearm Type Using Quantitative Class Characteristics, Young Wang

Graduate Theses, Dissertations, and Problem Reports (ETD)

The results of a data set of five models of 9 mm Luger caliber handguns suggest an algorithm such as the square of the Mahalanobis Distance as a step towards the creation of an electronic class characteristic database for cartridge cases to supplement the currently existing General Rifling Characteristic (GRC) database for bullets. The algorithm was validated using both hold-one out cross validation as well as on an entirely independent set of ground truth known cartridge cases which were blindly classified to mimic case work. A method for determining an objective threshold for inclusion onto a list for an investigator …

Enhancing Online Security With Image-Based Captchas, Brian M. Powell

Graduate Theses, Dissertations, and Problem Reports (ETD)

Given the data loss, productivity, and financial risks posed by security breaches, there is a great need to protect online systems from automated attacks. Completely Automated Public Turing Tests to Tell Computers and Humans Apart, known as CAPTCHAs, are commonly used as one layer in providing online security. These tests are intended to be easily solvable by legitimate human users while being challenging for automated attackers to successfully complete. Traditionally, CAPTCHAs have asked users to perform tasks based on text recognition or categorization of discrete images to prove whether or not they are legitimate human users. Over time, the efficacy …

Constitutional Rhetoric: The Genre Performances Of The Written Constitution In Transnational, Transcultural Contexts, Bhushan Aryal

Graduate Theses, Dissertations, and Problem Reports (ETD)

No abstract provided.