Digital Commons Network^™

Exploring The Cause Of Injury Or Death In Grain Entrapment, Engulfment And Extrication, Salah F. Issa

Open Access Dissertations

Grain entrapments and engulfments are one of most common hazards associated with grain storage facilities. Since the 1970’s over 1,880 incidents have been documented in agricultural confined spaces of which 65% of all recorded incidents were grain entrapments and engulfments. There have been several studies conducted on the contributing factors behind these incidents; however, there have been very few attempts to understand the environmental, physiological or psychological factors the victims experience while entrapped, engulfed, or extricated. This includes understanding how secondary injuries are caused by grain or during extrication by first responders. The research effort was divided into three segments. …

Securing Cloud-Based Data Analytics: A Practical Approach, Julian James Stephen

Open Access Dissertations

The ubiquitous nature of computers is driving a massive increase in the amount of data generated by humans and machines. The shift to cloud technologies is a paradigm change that offers considerable financial and administrative gains in the effort to analyze these data. However, governmental and business institutions wanting to tap into these gains are concerned with security issues. The cloud presents new vulnerabilities and is dominated by new kinds of applications, which calls for new security solutions. In the direction of analyzing massive amounts of data, tools like MapReduce, Apache Storm, Dryad and higher-level scripting languages like Pig Latin …

Gonadal Intersex In Teleosts: Mechanisms, Molecular Biomarkers And Diagnostic Assays, Ahmed M.E. Abdel-Moneim Mohamed

Open Access Dissertations

Natural and synthetic estrogenic and androgenic compounds are continuously released into aquatic ecosystems. Exposure of teleost fishes to these contaminants can negatively impact sex differentiation and reproductive output. Specifically, development of gonadal intersex in gonochoristic (fixed sex) fish species has been studied extensively in relation to exposure to this class of compounds. The main objectives of this dissertation were to: 1) conduct field and laboratory studies to investigate the molecular signaling pathways behind the development of gonadal intersex; and 2) establish molecular biomarkers and assays for testing the ability of environmental pollutants to develop this condition using a battery of …

The Application Of Natural Language Processing To Open Source Intelligence For Ontology Development In The Advanced Persistent Threat Domain, Corey T. Holzer

Open Access Dissertations

Over the past decade, the Advanced Persistent Threat (APT) has risen to forefront of cybersecurity threats. APTs are a major contributor to the billions of dollars lost by corporations around the world annually. The threat is significant enough that the Navy Cyber Power 2020 plan identified them as a “must mitigate” threat in order to ensure the security of its warfighting network.

Reports, white papers, and various other open source materials offer a plethora of information to cybersecurity professionals regarding these APT attacks and the organizations behind them but mining and correlating information out of these various sources needs the …

Ambient Ionization - Mass Spectrometry: Advances Toward Intrasurgical Cancer Detection, Alan Keith Jarmusch

Open Access Dissertations

My dissertation research has focused on the development of ambient ionization – mass spectrometry (MS) for clinical measurements, specifically intrasurgical cancer detection. The molecular differences between normal and cancerous tissue were detected via direct tissue analysis in vitro by touch spray ionization (TS) or by analyzing sectioned or smeared tissue using desorption electrospray ionization (DESI). The physical form of the tissue, e.g. in vitro sampling, sectioned, or smeared, was inconsequential in differentiating normal from cancerous tissue; however, the spectra acquired by TS and DESI differed due to differences in ionization processes. We envision that TS-MS and DESI-MS could impact diagnostic …

Functional And Structural Characterization Of The Mevalonate Diphosphate Decarboxylase And The Isopentenyl Diphosphate Isomerase From Enterococcus Faecalis, Chun-Liang Chen

Open Access Dissertations

Enterococcus faecalis causes a diverse range of nosocomial infections (in wounds, the gastrointestinal tract, the blood stream and the endocardium), and multidrug-resistant strains have become a serious issue across countries. Vancomycin, a FDA-approved drug for the disruption of the bacterial cell wall biosynthesis, has been utilized to treat infectious diseases caused by Enterococci; however, the prevalence of vancomycin-resistant enterococci (VRE) threatens communities all over the world. We aim at developing novel therapeutic strategies to control bacterial growth of Enterococci, and we focus on targeting two essential enzymes involved in poly-isoprenoid biosynthesis in Enterococcus faecalis; one is the mevalonate diphosphate decarboxylase …

A Method For Selecting Hvac Retrofit Solutions For Existing Small- And Medium-Sized Commercial Buildings, Bonggil Jeon

Open Access Dissertations

The primary purpose of the present study is to develop a framework and methodology for evaluating appropriate Heating, Ventilating, and Air Conditioning (HVAC) retrofit solutions that can be effectively retrofitted into different types of small- and medium-sized commercial buildings (SMSCB). Additionally, development of an advanced data-driven decision-making tool is introduced as a benefit of proposed framework. In recent years, considerable attention has been focused on retrofits of existing commercial buildings (IBE, 2013b). In fact, the Commercial Building Energy Consumption Survey (CBECS) 2003 (EIA, 2006) indicates that over 70% of existing commercial buildings across the United States are more than twenty …

Gravity-Assist Trajectories To Venus, Mars, And The Ice Giants: Mission Design With Human And Robotic Applications, Kyle M. Hughes

Open Access Dissertations

Gravity-assist trajectories to Uranus and Neptune are found (with the allowance of impulsive maneuvers using chemical propulsion) for launch dates ranging from 2024 to 2038 for Uranus and 2020 to 2070 for Neptune. Solutions are found using a patched conic model with analytical ephemeris via the Satellite Tour Design Program (STOUR), originally developed at the Jet Propulsion Laboratory (JPL). Delivered payload mass is computed for all solutions for select launch vehicles, and attractive solutions are identified as those that deliver a specified amount of payload mass into orbit at the target body in minimum time. The best cases for each …

Redox-Active Ligand Uranium Complexes For Approaches To Multi-Electron Chemistry, John J. Kiernicki

Open Access Dissertations

While transition metal complexes are known to participate in multi-electron redox chemistry to facilitate important organometallic transformations, actinides, due to their low redox potentials, have a propensity to perform single electron chemistry. Because of its highly reducing nature, the ability to control the electronics of low-valent uranium is highly sought after as this may lead to unprecedented reactivity. Our lab has specifically been interested in mediating multi-electron transformations at uranium by employing redox-active ligands. Redox-active ligands can be used to facilitate multi-electron processes such as oxidative addition and reductive elimination at single metal centers. Using primarily 2,6-((Mes)N=CMe)2C5H3N) ( MesPDIMe) as …

Plasmonic Devices Based On Transparent Conducting Oxides For Near Infrared Applications, Kim Jongbum

Open Access Dissertations

In the past decade, there have been many breakthroughs in the field of plasmonics and nanophotonics that have enabled optical devices with unprecedented functionalities. Even though remarkable demonstration of at photonic devices has been reported, constituent materials are limited to the noble metals such as gold (Au) and silver (Ag) due to their abundance of free electrons which enable the support of plasmon resonances in the visible range. With the strong demand for extension of the optical range of plasmonic applications, it is now a necessity to explore and develop alternative materials which can overcome intrinsic issues of noble metals …

Optimal Design Of Sound Absorbing Systems With Microperforated Panels, Nicholas Nakjoo Kim

Open Access Dissertations

As the development of technology makes economic prosperity and life more convenient, people now desire a higher quality of life. This quality of life is based not only on the convenience in their life but also on clean and eco-friendly environments. To meet that requirement, much research is being performed in many areas of eco-friendly technology, such as renewable energy, biodegradable content, and batteries for electronic vehicles.

This tendency is also obvious in the acoustics area, where there are continuing attempts to replace fiber-glass sound absorbers with fiber-free materials. The combination of microperfoated panels (MPP) (one of the fiber-free sound …

Hydrocode Modeling Of Oblique Impacts Into Terrestrial Planets, Jordan D. Kendall

Open Access Dissertations

The abundance of moderately siderophile elements (“iron-loving”; e.g., Co, Ni) in the Earth’s mantle is 10 to 100 times larger than predicted by chemical equilibrium between silicate melt and iron at low pressure, but it does match expectation for equilibrium at high pressure and temperature. Recent studies of differentiated planetesimal impacts assume that planetesimal cores survive the impact intact as concentrated masses that passively settle from a zero initial velocity and undergo turbulent entrainment in a global magma ocean; under these conditions, cores greater than 10 km in diameter do not fully mix without a sufficiently deep magma ocean. I …

New Marked Point Process Models For Microscopy Images, Dae Woo Kim

Open Access Dissertations

In developing new materials, the characterization of microstructures is one of the key steps. To characterize the microstructure, many microscope modalities have been devised and improved over decades. With the increase in image resolution in the spatial and time domains, the amount of image data keeps increasing in the fields such as materials science and biomedical engineering. As a result, image processing plays a critical role in this era of science and technology. In materials image analysis, image segmentation and feature detection are considered very important.

The first part of this research aims to resolve the segmentation problem caused by …

Observability And Observer Design For Switched Linear Systems, Scott C. Johnson

Open Access Dissertations

Hybrid vehicles, HVAC systems in new/old buildings, power networks, and the like require safe, robust control that includes switching the mode of operation to meet environmental and performance objectives. Such switched systems consist of a set of continuous-time dynamical behaviors whose sequence of operational modes is driven by an underlying decision process. This thesis investigates feasibility conditions and a methodology for state and mode reconstruction given input-output measurements (not including mode sequence). An application herein considers insulation failures in permanent magnet synchronous machines (PMSMs) used in heavy hybrid vehicles.

Leveraging the feasibility literature for switched linear time-invariant systems, this thesis …

Evaluating The Performance Of Passive Chilled Beams With Respect To Energy Efficiency And Thermal Comfort, Janghyun Kim

Open Access Dissertations

Existing modeling approaches for passive chilled beams determined from tests on individual chilled beams in a laboratory are not adequate for assessing overall energy usage and occupant comfort within building simulation programs. In addition, design guidelines for passive chilled beam systems are needed for identifying appropriate applications and optimal configurations. This thesis includes (i) extensive experimental studies for characterizing the performance of passive chilled beams, in both laboratory settings and in field studies, (ii) development of passive chilled beam performance prediction models, (iii) integration of these models into building simulation models/tools and (iv) use of building simulation for overall assessment …

Device Design Factors For Enhancing The Functionality Of Chronic Intracortical Microelectrodes, Heui Chang Lee

Open Access Dissertations

Intracortical microelectrodes are devices used in brain-computer interfaces (BCI) to help regain lost motor, sensory, and cognitive functions of individuals with neurological disorders. However, the long-term performance of microelectrode arrays is hampered by a series of inflammatory tissue responses. The consequence of the inflammatory response is the formation of a dense astroglial sheath around the vicinity of the electrode, impeding the electrical conduction between the electrode and neurons. Furthermore, due to the cascade of neuroinflammatory events, the number of neurons is significantly reduced near the electrode, manifested by decrease in signal-to-noise ratio (SNR) and the yield of electrodes. Over time, …

The Development Of Preclinical Strategies For Facilitation Of Lead Candidate Selection, Christopher Dale Kulczar

Open Access Dissertations

Chapter 1 details a background of techniques used for modeling the blood-brain barrier (BBB). The BBB represents a diffusive barrier to both paracellular and transcellular movement of many compounds in and out of the brain. The main rate- limiting barriers of the BBB include exclusive tight junctions that prevent the movement of hydrophilic molecules through intercellular gaps, and efflux proteins in the membrane which pump many hydrophobic molecules back into the blood. In addition, the BBB contains metabolizing enzymes, including Cytochrome P450s. This barrier acts to protect the vulnerable tissues of the brain from harmful xenobiotics, but also can serve …

Functional Diversity Enhances Detection Of Ecosystem Stability And Resolution Of Predator-Prey Interactions Within A Multitrophic Community, Ashley Lorraine Kissick

Open Access Dissertations

Habitat fragmentation and loss are principal factors that contribute to the decline of biodiversity which in turn has a negative impact on ecosystem function. There has been growing interest in understanding diversity’s role in the mechanisms behind ecosystem resilience with much attention focusing on how functional diversity, or the range of species’ ecological roles in a community, impacts ecosystem function. Under the functional insurance hypothesis, stability in ecosystems is maintained by species that perform similar functions but have asynchronous responses to disturbance. There are three proposed stability mechanisms that operate through species’ asynchronous responses: cross-scale resilience, response diversity, and density …

Fast Time- And Frequency-Domain Finite-Element Methods For Electromagnetic Analysis, Woochan Lee

Open Access Dissertations

Fast electromagnetic analysis in time and frequency domain is of critical importance to the design of integrated circuits (IC) and other advanced engineering products and systems. Many IC structures constitute a very large scale problem in modeling and simulation, the size of which also continuously grows with the advancement of the processing technology. This results in numerical problems beyond the reach of existing most powerful computational resources. Different from many other engineering problems, the structure of most ICs is special in the sense that its geometry is of Manhattan type and its dielectrics are layered. Hence, it is important to …

Quantifying Terrestrial Ecosystem Carbon Dynamics With Mechanistically-Based Biogeochemistry Models And In Situ And Remotely Sensed Data, Shaoqing Liu

Open Access Dissertations

Terrestrial ecosystem plays a critical role in the global carbon cycle and climate system. Therefore, it is important to accurately quantify the carbon dynamics of terrestrial ecosystem under future climatic change condition. This dissertation evaluates the regional carbon dynamics by using upscaling approach, mechanistically-based biogeochemistry models and in situ and remotely sensed data.

The upscaling studies based on FLUXNET network has provided us the spatial and temporal pattern of the carbon fluxes but it fails to consider the atmospheric CO2 effect given its important physiological role in carbon assimilation. In the second chapter, we consider the effect of atmospheric CO2 …

Improving Programmability And Performance For Scientific Applications, Chenyang Liu

Open Access Dissertations

With modern advancements in hardware and software technology scaling towards new limits, our compute machines are reaching new potentials to tackle more challenging problems. While the size and complexity of both the problems and solutions increases, the programming methodologies must remain at a level that can be understood by programmers and scientists alike. In our work, this problem is encountered when developing an optimized framework to best exploit the semantic properties of a finite-element solver. In efforts to address this problem, we explore programming and runtime models which decouple algorithmic complexity, parallelism concerns, and hardware mapping. We build upon these …

College Students' Suicidal Ideation: Testing The Predictions Of The Existential - Constructivist Theory Of Suicide, Jennifer Danielle Lockman

Open Access Dissertations

Suicide is the second leading cause of death in the college student population (Schwartz, 2006), and empirically supported theories for understanding suicide among college students are lacking (Lester, 1989; Prinstein, 2008; Rogers & Benson, 2013). Although not yet examined empirically, Rogers (2001) proposed an Existential - Constructivist Theory of Suicide (ECTS), in which existential distress and the inability to reconstruct meaning from adverse life events contribute to suicidal ideation. ECTS includes both interpersonal and intrapersonal drivers of suicidal ideation, and for this reason, may better explain suicidal ideation in college students than existing theoretical models. Existing research focuses on Joiner’s …

The Cloud-Radiative Forcing Of The U.S. Landfalling Atmospheric Rivers, Qianwen Luo

Open Access Dissertations

Atmospheric rivers (ARs) are narrow channels in the atmosphere that transport an enormous amount of moisture from the tropics to the higher latitudes. Streaks of highly reflective clouds are observed along with the ARs in satellite imagery. These clouds both influence the moisture transport of ARs, as well as modify the Earth-Atmospheric energy budget through pathways such as cloud-radiative forcing (CRF). This dissertation studies the CRF of the U.S. Landfalling ARs in weather and climate scales. Three crucial questions are addressed. First, how do clouds produced by the ARs modulate the moisture and heat balance of the Earth-Atmospheric system? Even …

What Broke Where For Distributed And Parallel Applications — A Whodunit Story, Subrata Mitra

Open Access Dissertations

Detection, diagnosis and mitigation of performance problems in today's large-scale distributed and parallel systems is a difficult task. These large distributed and parallel systems are composed of various complex software and hardware components. When the system experiences some performance or correctness problem, developers struggle to understand the root cause of the problem and fix in a timely manner. In my thesis, I address these three components of the performance problems in computer systems. First, we focus on diagnosing performance problems in large-scale parallel applications running on supercomputers. We developed techniques to localize the performance problem for root-cause analysis. Parallel applications, …

Modifying Burning Rate And Agglomeration Size In Aluminized Composite Solid Propellants Using Mechanically Activated Metals, Hatem Mohamed Belal

Open Access Dissertations

Agglomeration reduction techniques are important field in solid propellant industry, Large agglomeration results in excessive two phase losses. Tailored composite particles has been applied to tailor aluminum particle ignition and combustion. In this research, mechanical activated aluminum magnesium powders are synthesized, tested in both laser ignition using CO2 and propellant. Prepared powders categorized into particle size that suitable for propellant application. Laser ignition tests showed that the prepared powder are more reactive than magnalium which has the same Al:Mg weight ratio. Agglomeration capturing showed that the prepared powder produce much less than neat aluminum or even similar physical mixture of …

Energy Localization And Heat Generation In Composite Energetic Systems Under High-Frequency Mechanical Excitation, Jesus O. Mares

Open Access Dissertations

In this work, the ability to use high frequency mechanical excitation to generate significant heating within plastic bonded explosives, as well as single energetic particles embedded within a viscoelastic binder, is studied. In this work, the fundamental mechanisms associated with the conversion of high-frequency mechanical excitation to heat as applied to these composite energetic systems are thoroughly investigated.

High-frequency contact excitation has been used to generate a significant amount of heat within samples of PBX 9501 and representative inert mock materials. Surface temperature rises on the order of 10 °C were observed at certain frequencies over a range from 50 …

Hydrodynamics Of Swimming Microorganisms In Complex Fluids, Gaojin Li

Open Access Dissertations

Swimming motion of microorganisms, such as spermatozoa, plankton, algae and bacteria, etc., ubiquitously occurs in nature. It affects many biological processes, including reproduction, infection and the marine life ecosystem. The hydrodynamic effects are important in microorganism swimming, their nutrient uptake, fertilization, collective motions and formation of colonies. In nature, microorganisms have evolved to use various fascinating ways for locomotion and transport. Different designs are also developed for the locomotion of artificial nano- and microswimmers. In this study, we use several different computational models to investigate the behavior of microswimmers.

Microorganisms typically swim in the low Reynolds number regime, where inertia …

Managing Bacterial Wilt, Caused By Erwinia Tracheiphila, On Muskmelon With Early Control Of Striped Cucumber Beetle ( Acalymma Vittatum (F)), And Through Varietal Selection, Ahmad Shah Mohammadi

Open Access Dissertations

Muskmelon (Cucumis melo L), is an important vegetable crop in the United States. It is grown throughout the US, and Indiana ranked 4th in production after California, Arizona and Georgia with 12.4 thousand metric tons and market value of $7.6 million in 2015. Bacterial wilt of cucurbits, which is caused by Erwinia tracheiphila (E. F. Smith), and vectored by striped cucumber beetle (Acalymma vittatum (F)), is one of the most serious diseases of muskmelon that influences muskmelon quality and yield. Many cultivars of muskmelon are grown around the United States, especially in the Midwest. Muskmelon cultivars differ in …

Bayesian Causal Inference Of Cell Signal Transduction From Proteomics Experiments, Robert D. O. Ness

Open Access Dissertations

Cell signal transduction describes how a cell senses and processes signals from the environment using networks of interacting proteins. In computational systems biology, investigators apply machine learning methods for causal inference to develop causal Bayesian network models of signal transduction from experimental data. Directed edges in the network represent causal regulatory relationships, and the model can be used to predict the effects of interventions to signal transduction. Causal inference approaches applied to proteomics experiments use statistical associations between observed signaling protein concentrations to infer a causal Bayesian network model, but there is no experimental and analysis framework for applying these …

Bridge Maintenance To Enhance Corrosion Resistance And Performance Of Steel Girder Bridges, Luis M. Moran Yanez

Open Access Dissertations

The integrity and efficiency of any national highway system relies on the condition of the various components. Bridges are fundamental elements of a highway system, representing an important investment and a strategic link that facilitates the transport of persons and goods. The cost to rehabilitate or replace a highway bridge represents an important expenditure to the owner, who needs to evaluate the correct time to assume that cost. Among the several factors that affect the condition of steel highway bridges, corrosion is identified as the main problem. In the USA corrosion is the primary cause of structurally deficient steel bridges. …