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Phase-Space Manipulations Of Electron Beams For X-Ray Free-Electron Lasers And Inverse Compton Scattering Sources., Alexander V. Malyzhenkov

Graduate Research Theses & Dissertations

This dissertation describes advanced techniques of phase space manipulations of the electron beam for improving performance and efficiency of high brightness X-ray light sources based on the free-electron Laser (FEL) and inverse-Compton scattering (ICS) processes. In particular, it first discusses a novel bunch-compression scheme based on a double transverse-to-longitudinal phase-space exchanger -- dubbed emittance exchanger (EEX) -- separated by a demagnifying transverse-optics system. While the outline of the scheme is quite sophisticated, the basic physics behind it is quite straight-forward. The benefits and disadvantages of these scheme are compared to the conventional approach of compressing a bunch using a magnetic …

Adoption Of Plagiarism Detection Software By College Faculty, Patricia Meyer

Graduate Research Theses & Dissertations

This study explored the adoption level of a specific plagiarism detection software by college professors in a classroom environment. As universities and colleges struggle with the issue of plagiarism and maintaining high standards of integrity, technology tools have been created and provided to assist faculty in identifying if a student has plagiarized their work. The university that was used in this study provided plagiarism technology to their faculty known at Turnitin©. Turnitin© plagiarism software assist faculty in educating students on how to properly research and cite sources when completing their course work. The software is capable of detecting if a …

Theoretical Study Of Laser-Assisted Machining On Silicon Nitride Hollow Ceramic Cylinder Using Finite Element Method, Mudassar Hussain Ansari Mohammed

Graduate Research Theses & Dissertations

The most commonly used technique for machining ceramics is diamond grinding. It accounts for up to 75% of the manufacturing costs resulting in high cost of the product. An LED bulb offering increased brightness, energy saving and long life by using ceramic integration to LED chips costs around 10 times to a normal LED bulb. Complex geometries used in electronics, medical surgeries, aerospace, and automobile industries require the use of costly molds or powder metallurgy for low batch production which does not justify the cost. Laser Assisted Machining (LAM) is a process that uses a laser to locally heat the …

Exploring The Role Purpose-Related Experiences Can Play In Supporting Interest Development In Stem, Neil J. Naftzger

Graduate Research Theses & Dissertations

The focus of this study was to explore how select practices and approaches with a self-transcendent orientation delivered in STEM-oriented summer learning programs serving middle-school aged youth were related to both (a) in-the-moment experiences that over time are believed to be related to possible continued engagement and interest in STEM and (b) changes in STEM-related youth outcomes during the span of the program. Using data obtained from surveys collected using the experience sampling method, activity leader interviews, video footage of programing, and pre-post youth surveys, a series of multilevel models were constructed to assess how activity leader practices that put …

Hydrogen, Carbon, And Oxygen Isotopes In Prosopis Sp. Trees: A New Climate Proxy For Holocene Paleoclimate In The Atacama Desert, Chile, Elizabeth Joy Olson

Graduate Research Theses & Dissertations

The spatial ubiquity of trees in terrestrial ecosystems worldwide facilitates the use of stable isotope research in tree-rings to address a wide-range of interdisciplinary questions related to climate, ecology, archaeology, and hydrology. This dissertation focuses on the development and application of Prosopis tamarugo tree-ring stable isotope records as a paleoclimate proxy for the Atacama Desert, Chile. Current paleoclimate proxies from this region lack the spatial and temporal resolution to quantify a causal mechanism for observed Holocene hydroclimate variability. P. tamarugo tree-ring isotopes provide a high-resolution proxy that facilitates the reconstruction of hydroclimate variability at a regional scale. In order to …

Evaluating The Role Of Energy Demand Prediction And Renewable Energy Utilization On Energy Dependency Management: A Generic System Dynamics Model, Emad Rabiei Hosseinabad

Graduate Research Theses & Dissertations

Supplying energy has become one of the biggest concerns of developed countries due to the growing energy needs in the last decades. Security of energy supply has forced countries to rely more on energy imports from external sources, and become energy dependent to a greater extent. Utilizing available renewable energy resources has been characterized as a reliable indicator to mitigate energy dependency in countries as well as securing the supplying of energy-based needs in the future. This research explores the impact of renewable energies as trustful resources in mitigating energy imports form external sources with investigation of its viability with …

Surface Engineering And Monomer Design For Light-Mediated Ring Opening Metathesis Polymerization, Ishan A. Fursule

Theses and Dissertations--Chemical and Materials Engineering

Stimuli-responsive materials are changing the landscape of actuated materials, optoelectronics, molecular machines, solar cells, temporary memory storage, and biomedical materials. Specifically, photo-responsive polymers have gained acceleration in research and application since the last two decades in the form of a surface coating and micro-patterns. Light as a stimulus can be coherent, mono or polychromatic, tunable for power (intensity) and energy (wavelength), and has precise spatiotemporal control. Conventional surface coating techniques such as spin coating are unable to impart properties to the coatings in terms of sturdiness, homogeneity, uniformity over the complex surface, post deposition modification, and process efficiency. Also, in …

Application Of Process Systems Engineering Tools And Methods To Fermentation-Based Biorefineries, Kwabena Darkwah

Theses and Dissertations--Chemical and Materials Engineering

Biofuels produced from lignocellulosic biomass via the fermentation platform are sustainable energy alternatives to fossil fuels. Process Systems Engineering (PSE) uses computer-based tools and methods to design, simulate and optimize processes. Application of PSE tools to the design of economic biorefinery processes requires the development of simulation approaches that can be integrated with existing, mature PSE tools used to optimize traditional refineries, such as Aspen Plus. Current unit operation models lack the ability to describe unsteady state fermentation processes, link unsteady state fermentation with in situ separations, and optimize these processes for competing factors (e.g., yield and productivity). This work …

Design And Analysis Of Curcumin Conjugated Poly(Beta-Amino Ester) Networks For Controlled Release In Oxidative Stress Environments, Carolyn T. Jordan

Theses and Dissertations--Chemical and Materials Engineering

Oxidative stress, the imbalance of free radical generation with antioxidant defenses, leads to cellular inflammation, apoptosis and cell death. This compromised environment results in debilitating diseases, such as oral mucositis (OM), atherosclerosis, and ischemia/reperfusion injury. Antioxidant therapeutics has been a proposed strategy to ameliorate these imbalances and maintain homeostatic environments. However, the success of these approaches, specifically curcumin, has been limited due to characteristics such as hydrophobicity and high reactivity when released as bolus doses to contest to oxidative stress induced diseases. The development of a controlled release system to aid in protection of the antioxidant capacity of curcumin, as …

Defense In Depth Network Perimeter Security, Anuoluwapo Ope Fatokun

Masters Theses

Defense in depth network perimeter security has always be a topic of discussion for a long time as an efficient way of mitigating cyber-attacks. While there are no 100% mitigating method against cyber-attacks, a layered defense in depth network perimeter security can be used to mitigate against cyber-attacks. Research have shown a massive growth in cyber-crimes and there are limited number of cyber security expert to counter this attacks. EIU as an institution is taking up the responsibility of producing cyber security graduates with the new Master of Science in Cyber Security program that started in Fall 2017.

This research …

Construct Validity Of The Learning-To-Learn Scales (Ltls) With A Preschool And Kindergarten Sample, Kassandra Jane Charles

Masters Theses

Learning behaviors, "observable behavior patterns that children display as they approach and undertake school learning tasks" (Yen, Konold, and McDermott, 2004, p. 159) and "the degree to which children adopt beneficial approaches to learning" (Rikoon, McDermott, & Fantuzzo, 2012, p. 273) have been shown to account for a substantial amount of variance in academic achievement and add predictive validity for future academic achievement. Prediction of academic achievement is vital when making individual decisions concerning academic placement, diagnosis, early intervention, and student selection (Yen, Konold, & McDermott, 2004). The current study assessed the concurrent criterion validity of the Learning-to-Learn Scales (LTLS) …

A Photo Illicit Study Of Black Women's Sense Of Belonging At A Predominately White Institution, Kayla Alexandria Slusher

Masters Theses

This qualitative study sought to examine how Black women define and create their sense of belonging while attending a predominately White institution using a photovoice approach. The women took photographs of spaces that they frequently occupy and then engaged in a face-to-face interview to discuss the photographs. The researcher also investigated four Black women, ranging from junior to graduate level, to identify how they developed a sense of belonging at the research site institution. Results of the study showed that a feeling of comfort was most important when identifying belongingness in a space. The participants were able to create a …

Oxidation Of Β-O-4 Lignin Model Compounds And Application To Lignin Linkage Degradation Facilitated By Mechanochemical Treatment And Two-Step Oxidative Depolymerization, Soledad G. Yao

Theses and Dissertations--Chemistry

The oxidation of lignin model compounds was studied in conventional solvents in parallel with oxidations in ionic liquid solvents. Catalyst systems were investigated in ionic liquid solvents to determine how reaction rates and the selectivity for benzylic carbon oxidation were affected. Oxidation rates were often lower in ionic liquids than in conventional solvents ‒ as indicated by lower conversion in a standard reaction time ‒ likely due, at least in part, to the higher viscosity of ionic liquids. Mechano chemical treatment of Indulin AT kraft lignin by ball milling with KOH and toluene produced significant carbonyl functionality, among other changes. …

Applications Of Cell-Derived Vesicles: From Single Molecule Studies To Drug Delivery, Faruk H. Moonschi

Theses and Dissertations--Chemistry

Single molecule studies can provide information of biological molecules which otherwise is lost in ensemble studies. A wide variety of fluorescence-based techniques are utilized for single molecule studies. While these tools have been widely applied for imaging soluble proteins, single molecule studies of transmembrane proteins are much more complicated. A primary reason for this is that, unlike membrane proteins, soluble proteins can be easily isolated from the cellular environment. One approach to isolate membrane proteins into single molecule level involves a very low label expression of the protein in cells. However, cells generate background fluorescence leading to a very low …

Protein Suppression Of Flavin Semiquinone As A Mechanistically Important Control Of Reactivity: A Study Comparing Flavoenzymes Which Differ In Redox Properties, Substrates, And Ability To Bifurcate Electrons, John Patrick Hoben

Theses and Dissertations--Chemistry

A growing number of flavoprotein systems have been observed to bifurcate pairs of electrons. Flavin-based electron bifurcation (FBEB) results in products with greater reducing power than that of the reactants with less reducing power. Highly reducing electrons at low reduction midpoint potential are required for life processes of both aerobic and anaerobic metabolic processes. For electron bifurcation to function, the semiquinone (SQ) redox intermediate needs to be destabilized in the protein to suppress its ability to trap electrons. This dissertation examines SQ suppression across a number of flavin systems for the purpose of better understanding the nature of SQ suppression …

Representation Of The Titanic In Children's Literature, Charity Rose Huwe

Masters Theses

State and national education initiatives are the driving force behind increased exploration of diverse texts, namely informational texts. Trade books offer opportunity for interdisciplinary units to develop through the rise of informational text use in both English/language arts and history/social studies. Primary source documents serve as a liaison to filing gaps in the information left out from textbooks and trade books. A more thorough understanding of historical figures and events are a result of such analysis. The initiatives do not dictate specific curricular material; teachers use their discretion when choosing available trade books, primary documents, and other curricular resources. In …

A New Model For Calculating The Transient Displacement Field Within A Linear Elastic Isotropic Solid With A Through Hole Under Dynamic Impact : A 3d Model Is Developed And A 2d Case Study Is Examined, Drew Mitchell

Graduate Research Theses & Dissertations

This paper presents an exact analytical solution in tensor notation for solving the elastic wave propagation for any 3-dimensional shape objects with a hole (from infinitesimal to finite). For validating the proposed model, a case study of an axisymmetric thick walled cylindrical metallic tube with finite length under a dynamic impact, was modeled and computed. The case study was also computed and validated by using an explicit time integration finite element method, LS-Dyna, for comparison purpose. The LS-Dyna simulation results were used to calculate the boundary conditions for the proposed model for obtaining the analytical solution because in the real …

Anatomy Of A Precision Grip In Human And Non-Human Primates, Caitlin Marie Bemis

Graduate Research Theses & Dissertations

Prehensility is a hand activity that applies forces while grasping an object. In the crudest sense, prehensile movements of the hand can be divided into two types based on an actor needing a precision or a power grip. To analyze prehensility more specifically, I suggest that the movements of the hand can be divided into three categories including power, modified precision, and true precision grips. A power grip is when an object is held in one hand with the aid of the palm with fingers buttressing the object, while a true precision grip is when an object is picked up …

Assessing The Jurassic Cleveland-Lloyd Bone Bed Predator Trap Hypothesis By Statistical Comparison Of Allosaurus Fragilis And Pleistocene La Brea Canis Dirus Femora, Angela D. Reddick

Graduate Research Theses & Dissertations

Since its discovery in 1939, the Late Jurassic, Cleveland-Lloyd Dinosaur Quarry (CLDQ) has been assumed to be a Jurassic predator trap by most visitors to the site. This idea's longevity is due in part to the disproportionately high ratio of carnivores to herbivores (3:1) uncovered from the quarry. However, despite decades of active research on the taphonomy and geochemistry of the deposit, the predator trap hypothesis remains unproven. In order to test whether the quarry has or does not have the characteristics of a predator trap, this study specifically analyzed the population of the quarry's most abundant animal, Allosaurus fragilis. …

Assessing And Supporting The Use Of Fuzzy Cognitive Maps To Simulate Complex Phenomena, Eric Lavin

Graduate Research Theses & Dissertations

To study complex phenomena, modelers have used a wide variety of modeling techniques (e.g. agent-based modeling). While these are powerful and useful modeling methods, they are not perfect. To improve our models of complex problems, we need to apply methods that handle uncertainty such as Fuzzy Cognitive Maps (FCM). This thesis will show that while we use simulation models to evaluate complex phenomena, we do not apply FCMs in these evaluations very often. While they are commonly used in participatory modeling to handle uncertainty in small models, this thesis proposes and evaluates a new method to handle uncertainty in much …

Bayesian Methods For Optimal Treatment Allocation, Saptarshi Chatterjee

Graduate Research Theses & Dissertations

In chronic diseases such as cancer, physicians make multiple treatment decisions over the course of a patient's disease depending on his/her biological characteristics and accrued information. Essentially, the treatment rule at each decision point is a function which takes the patients' biomarker information, treatment and outcome history available up to that point as an input and returns the treatment choice as an output. In the single treatment setting, the optimal treatment decision can be obtained by a regression model on the mean outcome conditional on treatment and covariates, where the optimal treatment is the one that corresponds to the most …

Beyond Branch : An Examination Of The American Presidency And Conscription Policies, Victoria Bryant Stewart

Graduate Research Theses & Dissertations

Despite its unpopularity when used during the American Civil War, conscription was used during World War I, World War II, the Korean War, and the Vietnam War. Conscription, mandatory military service, required America's male population to be registered and serve the nation. These men, between the ages of eighteen and forty-five, fought in these declared and undeclared wars. Conscription laws lapsed, which drastically reduced the size of the military. Members of Congress enacted legislation to initiate new conscription calls to serve the military needs of the nation. President Abraham Lincoln, President Woodrow Wilson, President Franklin Roosevelt, President Harry S. Truman, …

A Dependent Competing Risks Model, Yiqing Wang

Graduate Research Theses & Dissertations

The competing risks model considers the setting where subjects or units are exposed to multiple risks one of which may eventually cause the occurrence of the event, such as failure or recurrence or death. There is a substantial literature on identifiability and inference in both parametric and nonparametric models for competing risks. In this dissertation, we propose a parametric model for dependent competing risks that can be motivated by a frailty approach as well as by a copula approach. We establish identifiability conditions for this proposed model. We also consider competing risks regression framework and establish identifiability and methods for …

Efficiently Comparing Mental Representations : Visualizing And Matching Causal Networks, Vishrant Krishna Gupta

Graduate Research Theses & Dissertations

A concept map can be used to represent knowledge. A causal map is a type of concept map and a graphical way that can be used to define thinking of an individual about a system by using links between nodes in a network to represent causation or influence. A causal map thus can be used to solve ill-structured problems and evaluate student's assignment. Causal maps can also be used to generate feedback for a student by comparing it with an expert map. However, exact network comparison is an NP-complete problem and is known to be graph isomorphism problem. In order …

Effective School Leaders And Student Achievement : An Examination Of 265 Schools In Northern Illinois, Jason Bednar

Graduate Research Theses & Dissertations

This dissertation examined the relationship between scores on the Effective Leader strand of the 5Essentials Survey for elementary school principals in the suburban collar counties around Chicago and student achievement on state assessments in Illinois, using longitudinal data from 2013 to 2015. This study selected only those schools which gave the 5Essentials survey in both years. Significant associations were found between Effective Leader score and student achievement over time. In addition, several demographic variables such as SES, teacher retention, and principal retention were associated with student achievement. Implications are discussed.

College Major Choice : Exploring The Perspectives Of Expectancy And Value Placed On Stem Fields By Female High School Students, Diane O'Connell

Graduate Research Theses & Dissertations

This qualitative case study examined the expectancy beliefs and value placed on science, technology, engineering, and mathematics (STEM)-fields by female high school students as they relate to college major choice. Nineteen female high school seniors in a STEM-focused academic program from a large suburban high school in the Midwest identified their intended college major choice and explained their career goals along with their educational experiences that were helpful in the decision-making process. Through reflective essays, focus group discussions, and interviews, perspectives emerged that played a role in choosing a college major. The findings suggested that expectancy to be successful, along …

An Investigation Into The Effects Of Temperature On The Rheological Characteristics Of Hybrid Nanofluids, Nanda Kishore Saini

Graduate Research Theses & Dissertations

Over the past several decades, nanofluids have exhibited a great potential of enhanced heat transfer performance over conventional heat transfer fluids. These innovative nanofluids are synthesized through the dispersion of a variety of types of nanometer-sized materials throughout the base fluid that consists of either metal, metal-oxides, or non-metals particle suspensions. These nanoparticle suspensions play an important role in altering the intrinsic properties of a base fluid, and this especially true for its shear viscosity. Studies have shown that the rheological response of the base fluid under shear changes from a characteristic Newtonian behavior to non-Newtonian (shear thinning) behavior when …

Investigating The Link Between A Middle-Level Geography Professional Learning Community And Classroom Practice, Hazel Ellie Reitz

Graduate Research Theses & Dissertations

This phenomenological case study examined the link between teacher practice within the classroom and a newly implemented middle school social studies Professional Learning Community (PLC). More specifically, the use of mandates, theories, and activities were investigated through a series of teacher interviews, classroom observations, post-observation discussions, and PLC observations. The participants included in this study were from one seventh grade geography PLC, consisting of ten members, three of which agreed to be further interviewed and observed. Member checking, peer reviews, and a reflexive journal were used to ensure the trustworthiness of the data, and open and selective coding were used …

Using Arts-Facilitated Reflection To Elicit Meaning-Making Explorations From Adult And Higher Education Master's-Level Students On Topics Related To Diversity, Social Justice And Inclusion, Amy S. Franklin

Graduate Research Theses & Dissertations

The purpose of the study was to investigate how student affairs graduate students make meaning of their prior significant experiences or professional development activities related to diversity, social justice, and inclusion (DSJI). The study examined how participants describe a significant experience related to DSJI; how participants believe that these experiences regarding DSJI influence their work as student affairs educators; how participants describe an emerging professional identity as an inclusive practitioner because of these experiences; and how participants describe the influence of arts-based research practices on their reflection about topics related to DSJI. Findings included participants' understandings of DSJI; that diversity-related …

Diffuse Scattering And Local Order In Lead-Based Relaxor Ferroelectrics, Matthew J. Krogstad

Graduate Research Theses & Dissertations

Relaxor ferroelectrics are characterized by their dielectric permittivity, and some of these materials display outstanding electromechanical coupling, a property that makes them useful in applications from sonar and ultrasound to precision actuators. However, there is a surprising lack of consensus regarding the local structure of these materials and how it relates to their useful bulk properties. A common feature of many proposed mechanisms is the importance of short-range order differing from the long-range symmetry of the material. Such a difference between short-range and long-range order makes these materials ideal candidates for study via diffuse scattering, a technique sensitive to differences …