Digital Commons Network^™

Self-Other Agreement In Person And Thing Orientations, Miranda M. Mcintyre

Open Access Dissertations

Personality judgments are inherently subjective—perceptions of one’s own traits often differ from perceptions held by others. However, research on personality relies overwhelmingly on self-reports. This lack of methodological diversity threatens the validity and reliability of individual differences research. The current work addresses this common-method bias for person orientation and thing orientation, which are personality traits that reflect interest in different aspects of individuals’ environments. Three studies investigated self-other agreement in these orientations and compared convergence with Big Five traits and vocational interests. Study 1 (N = 193) presents evidence that thirteen individual difference constructs vary in observability and desirability, which …

Characterization Of Horizontal Air-Water Two-Phase Flow In Different Pipe Sizes, Ran Kong

Open Access Dissertations

The highly asymmetric void distribution in horizontal two-phase flow due to buoyancy adds further complications to the study of horizontal flow, both experimentally and analytically. As such, there has been limited research on horizontal two-phase flow, comparing with the extensively studied vertical two-phase flow. However, understanding of horizontal two-phase flow is essential to the correct simulation of two-phase flow in engineering systems such as nuclear power plant. With this in mind, the current work characterizes the horizontal air-water two-phase flow in straight pipes of different pipe sizes. An extensive experimental database is established for both global and local two-phase flow …

A Pseudo-Rigorous Lidar System Calibration Approach And A Strategy For Stability Analysis, Megan M.G. Miller

Open Access Dissertations

With LiDAR systems being a crucial technology for near real-time mapping and spatial analysis, the user community needs standardized LiDAR system calibration procedures that are robust for the wide range of users and scenarios. More specifically, a comprehensive calibration approach should entail rigor in automation for matching and handling the irregularity of LiDAR data, as well as generality in terms of type of terrain used and of raw measurement availability. Most times, the sensor model and raw measurements are unavailable to the end user, and therefore rigorous LiDAR system calibration is not possible. For this scenario, pseudo-rigorous methods have been …

Visual Analytics To Support Atomistic Simulations Design, Daniel Felipe Mejia Padilla

Open Access Dissertations

Nowadays, complex simulations of a variety of processes are extensively used in academia and industry. Particularly in academia, powerful scientific software tools are constantly developed to simulate complex systems; for instance, simulations of quantum transport using the non-equilibrium greens Function formalism. The potential impact of these scientific tools in industry is huge, but it is hindered by the lack of usability of the software by those who are not deeply familiar with it. Visual analytics is a new field that has shown the positive impact of interactive visualizations in software usability and the cognitive process of the user. This research …

Hybrid Cloud Model Checking Using The Interaction Layer Of Harms For Ambient Intelligent Systems, Mauricio Alejandro Gomez Morales

Open Access Dissertations

Soon, humans will be co-living and taking advantage of the help of multi-agent systems in a broader way than the present. Such systems will involve machines or devices of any variety, including robots. These kind of solutions will adapt to the special needs of each individual. However, to the concern of this research effort, systems like the ones mentioned above might encounter situations that will not be seen before execution time. It is understood that there are two possible outcomes that could materialize; either keep working without corrective measures, which could lead to an entirely different end or completely stop …

Mapping Soils Of The Uasin Gishu Plateau, Kenya With Limited Data Using A Knowledge-Based Inference Mapping Approach, Mercy W. Ngunjiri

Open Access Dissertations

Kenya has a current population of ~47 million people living on an arable land area of ~56,000 km2 (~1.7 times the area of Indiana). With an annual growth rate of ~800,000 people, there is tremendous pressure on the soil resource to produce more food. Understanding the available soil resources is important to increase and sustain agricultural productivity. Soil surveys made with traditional approaches are too expensive, and new surveys must rely on limited data, legacy information and new digital mapping techniques. We used three knowledge-based inference soil mapping approaches to predict soil types and properties for the Uasin Gishu Plateau …

Absolute Convergence Of The Twisted Arthur-Selberg Trace Formula, Abishek Parab

Open Access Dissertations

We show that the distributions occurring in the geometric and spectral side of the twisted Arthur-Selberg trace formula extend to non-compactly supported test functions. The geometric assertion is modulo a hypothesis on root systems proven among other cases, when the group is split. The result extends the work of Finis-Lapid (and M¨uller, spectral side) to the twisted setting. We also give an application towards finiteness of residues of certain Rankin-Selberg L-functions.

Towards Ontology-Based Phishing Detection, Gilchan Park

Open Access Dissertations

Detection of phishing emails is a topic that has received a lot of attention both from academia and industry due to the devastating effects that phishing enabled data breaches have had on private individual and companies. Notwithstanding enormous efforts to detect phishing attacks, phishing still remains a major threat in information security, and the damages from it are not forecasted to disappear in the near future. One of the reasons is the diversity of attacks, especially within spear phishing and whaling. Another reason is that the natural language part of the detectors is usually devoid of semantics. Many of the …

College Students And Athletes: Identity Adherence, Injury, Illness, Depression, Social Support, And Problem Behaviors, Samuel L. Nekvasil

Open Access Dissertations

College students are at pivotal time in their life for identity development. They are typically away from home for the first time, independently making decisions while also striving to maintain their academic performance. A subset of this population, college athletes, face a number of unique challenges often connected with their potentially competing identities as athletes and students (i.e., athletic and academic identities). In addition, when injury/illness occurs, identity adherence may shift for all students (i.e., athletes and non-athletes) and there is the potential that they may engage in problem behaviors (i.e., risky sexual behavior, illicit drug use, problem alcohol use, …

Cooperative Multiple Agents Based Algorithm For Optimal Evacuation Planning Under Time–Varying Uncertainty, Byung Hoon Oh

Open Access Dissertations

In the aftermath of natural disasters, the optimal evacuation planning plays a crucial role in saving people’s lives by providing plans to timely extricate victims to safe locations. For the evacuation in the aftermath, aerial vehicles (e.g., helicopters) become efficient assets when a disaster area is difficult to access by ground vehicles due to the destruction of the road network, or the large number of victims affected. In this regard, a mathematical model and efficient solution is necessary for optimal evacuation planning using a fleet of aerial vehicles, as proposed in this dissertation. The Optimal Evacuation Planning Problem (OEPP) is …

Fostering Internal Motivation To Respond Without Sexism: A Self-Determination Theory Approach, Laura Ruth Parker

Open Access Dissertations

Internal motivation to respond without sexism (Klonis, Plant, & Devine, 2005) may be a powerful way to combat sexism and gender discrimination. However, little is known about how this motivation develops. Drawing from self-determination theory (Ryan & Deci, 2000), Experiment 1 demonstrated that teaching people about the harmful consequences of sexism in a way that supported their fundamental human needs for autonomy and competence strengthened internal motivation. However, harm information and fundamental need support only increased internal motivation for participants low in social dominance orientation (SDO; Pratto, Sidanius, Stallworth, & Malle, 1994). Participants low in SDO reported the greatest recognition …

The Effective Reproduction Number For A Class Of Mixing Matrices In Meta-Population Models In Epidemiology, Gayane Poghotanyan

Open Access Dissertations

Meta-populations models that account for population heterogeneities due to age, gender, spatial location, etc., and incorporate realistic mixing matrices are important for identifying optimal intervention strategies that can mitigate outbreaks of infectious diseases. Problems of finding optimal vaccination strategies for infectious diseases (including measles, mumps and rubella, HIV, and many others) based on such meta-population models are considered in this thesis. The problems are stated in the form of constrained minimization problems for the effective reproduction number, which is a threshold quantity that determines whether or not the disease can spread in the population. One of the most important findings …

Impact Of Changing Climate On Water Resources In The Western Lake Erie Basin Using Swat, Sushant Mehan

Open Access Dissertations

Water quality impairment in the Great Lakes Region has become a major concern for the scientific community. With increasing high intensity short duration precipitation events and rise in temperatures, there is the need to determine the impacts of a changing climate on water resources in the Great Lakes region. This is especially so in the Western Lake Erie Basin (WLEB); Lake Erie is prone to toxic harmful algal blooms due to climate variations and large nutrient and sediment inflows from the surrounding, primarily agricultural lands. The aim of this study was to determine the implications of future climate conditions on …

Residual Dimension Of Finitely Generated Nilpotent Groups, Mark A. Pengitore

Open Access Dissertations

In previous work, the author claimed an effective characterization for residual finiteness and lower asymptotic bounds for conjugacy separability of all finitely generated nilpotent groups. However, a counterexample to the characterization of residual finiteness for finitely generated nilpotent groups was communicated to the author which also had consequences to the lower asymptotic bound provided for conjugacy separability for the class of finitely generated nilpotent groups. Subsequently, the statements of the asymptotic characterization of residual finiteness and the asymptotic lower bound for conjugacy separability for the same class of groups along with their proofs are incorrect. In this article, we provide …

Essays On Structural Econometric Modeling And Machine Learning, Hajime Shimao

Open Access Dissertations

This dissertation is composed of three independent chapters relating the theory and empirical methodology in economics to machine learning and important topics in information age . The first chapter raises an important problem in structural estimation and provide a solution to it by incorporating a culture in machine learning. The second chapter investigates a problem of statistical discrimination in big data era. The third chapter studies the implication of information uncertainty in the security software market.

Structural estimation is a widely used methodology in empirical economics, and a large class of structural econometric models are estimated through the generalized method …

A Quantitative Study Of Faculty Retention And Promotion In Engineering Across Gender, Matilde L. Sanchez-Pena

Open Access Dissertations

The retention and promotion of a diverse engineering faculty body play a primary role in the advancement of the field. Failure to retain engineering faculty has significant economic implications for institutions. Additionally, the availability of role models and potential mentors for women and other minorities is paramount for the continuing diversification of the field. Prior research has documented additional challenges faced by women faculty in engineering when compared to men; such evidence has resulted in significant attempts to attenuate such disparities among faculty at all ranks. From the institutional perspective, examining retention and promotion times across gender would help to …

Spectroscopy Of Ultracold Lithium-Rubidium Molecules, Ian Stevenson

Open Access Dissertations

I present spectroscopic data on ultracold lithium-rubidium molecules in a dual species magneto-optical-trap in order to find suitable intermediate states to transfer population to the rotational, vibrational and electronic ground state via a stimulated Raman process. First, I improved the accuracy of the energetic location of the ground state by two orders of magnitude using photoassociation as a spectroscopic tool to measure the energy of bound states relative to the scattering continuum. Second, we studied the d 3Π-D 1Π and A 1Σ+ -b 3Π0+ excited electronic manifolds with a combination of resonantly-enhancedmulti-photon-ionization and depletion spectroscopy finding suitable singlet-triplet mixed states …

Iii-V And 2d Devices: From Mosfets To Steep-Slope Transistors, Mengwei Si

Open Access Dissertations

With silicon CMOS technology approaching the scaling limit, alternating channel materials and novel device structures have been extensively studied and attracted a lot of attention in solid-state device research. In this dissertation, solid-state electron devices for post-Si CMOS applications are explored including both new materials such as III-V and 2D materials and new device structures such as tunneling field-effect transistors and negative capacitance field-effect transistors. Multiple critical challenges in applying such new materials and new device structures are addressed and the key achievements in this dissertation are summarized as follows: 1) Development of fabrication process technology for ultra-scaled planar and …

Electrophysiological And Spatial Orientation Ability Differences In Expert And Novice Aircraft Pilots, Karthik Sukumar

Open Access Dissertations

Exploring differences between experts and novices by observing task-specific performance has been an important area of research in several domains. This study examined differences in expert and novice aircraft pilots based on their cortical activity and spatial orientation ability. Twenty-eight aircraft pilots (eight experts, 20 novices) performed 23 in-flight sequences inside a flight simulator while their cortical activity was recorded using an electroencephalographic (EEG) device. Thirty-two aircraft pilots (11 experts, 21 novices) attempted a 30-question multiple-choice spatial orientation ability test. Outcomes of the study revealed significant differences in cortical activity between expert and novice groups. Novice pilots projected higher mental …

Sublaplacians On Real Flag Manifolds, Andrew Ursitti

Open Access Dissertations

Hypoelliptic differential operators and associated geometries with origins in Lie theory are studied. We prove upper bounds on the dimension of Killing fields of analytic pseudosubriemannian manifolds under certain technical hypotheses. Existence and uniqueness results for adapted complex structures in open subsets of cotangent bundles of analytic subriemannian manifolds are proved. A generalized Lichnerowicz theorem expressing the difference between a connection laplacian and a Dirac laplacian for arbitrary linear connections and quadratic forms is proved, along with a preliminary result in local index theory for subriemannian metrics. We prove general results on the ubiquity of hypoelliptic sublaplacians arising in reductive …

Assessing Novel Bioelectric Effects Of Nanosecond Pulsed Electric Fields On Cell Stimulation, Proliferation And Microorganism Inactivation, Ram Anand Vadlamani

Open Access Dissertations

Bioelectrics is the application of electric fields to cells in a conducting media, treating the cell as a circuit comprising resistors and capacitors (membranes and intracellular fluids respectively). Recent advancements in construction of nanosecond pulse generators allow for construction of low cost devices capable of generating nanosecond pulsed electric fields (nsPEFs). These fields are capable of forming pores on the extra and intra cellular membranes, while also affecting intracellular organelles, DNA and the nucleus. With the first generation of nano-signalling devices set to enter the medical field for treatments ranging from carcinomas to regenerative therapy, the intent of this study …

Analytical Methods For Structured Matrix Computations, Xin Ye

Open Access Dissertations

The design of fast algorithms is not only about achieving faster speeds but also about retaining the ability to control the error and numerical stability. This is crucial to the reliability of computed numerical solutions. This dissertation studies topics related to structured matrix computations with an emphasis on their numerical analysis aspects and algorithms. The methods discussed here are all based on rich analytical results that are mathematically justified. In chapter 2, we present a series of comprehensive error analyses to an analytical matrix compression method and it serves as a theoretical explanation of the proxy point method. These results …

Investigating Airflow Distribution And Contaminant Transport In Commercial Aircraft Cabins, Ruoyu You

Open Access Dissertations

Overhead gaspers are prevalently installed in aircraft cabins as a personalized ventilation system. The air distribution in cabins with gaspers on is crucial for creating a thermally comfortable and healthy cabin environment. This study aims to model the air distribution and contaminant transport in commercial aircraft cabins with gaspers on.

This study first conducted experimental measurements of airflow distribution in a mockup of half of a full-scale, one-row, single-aisle aircraft cabin with a gasper on. Particle image velocimetry (PIV) was used to measure the complex airflow field above a human simulator. This investigation then used the measured data to evaluate …

Mapping Underground Utilities With Complex Spatial Configurations Using Ground Penetrating Radar, Chenxi Yuan

Open Access Dissertations

Records of the locations, measures, and properties of over 20 million mileage underground utility networks in the US are incomplete, inaccurate, and many times unavailable. This lack of information of underground pipes and cables is a primary reason for over six million of utility interruptions every year that cause injuries, fatalities, property damages, and environmental pollutions, amounting to over eight billions of dollars in loss. It also poses a critical challenge to maintaining and upgrading the ageing underground infrastructure with a D+ score according to the American Society of Civil Engineers’ Report Card. There is a critical need for accurately …

Anisotropic Flow And Fiber Orientation Analysis Of Preimpregnated Platelet Molding Compounds, Drew E. Sommer

Open Access Dissertations

Process modeling of prepreg platelet molded composites (PPMC) is of interest for enabling optimized design of PPMC structures. The platelet mesoscale and the part scale are on the same order, which introduces several modeling challenges including the treatment of variability. The fiber length and concentration results in anisotropic rheological behavior during processing. Current commercial flow simulation tools do not include anisotropic constitutive models and utilize second order orientation tensor methods for the fiber orientation which requires significant interpretation to inform a structural model. A flow and fiber orientation model to predict the final orientation state in molded parts should treat …

Efficient Fast Computing For U-Statistics Via A-Optimal Subsampling, Mingao Yuan

Open Access Dissertations

U-statistics has been widely studied and used in both statistics and machine learning. One challenge in application of U-statistics is the intensively demanding computation. In this thesis, we propose subsampling method to fast compute U-statistics. Our work is fourfold: (1) we formally accommodate uniform subsampling to fast computing of U-statistics; (2) we propose A-optimal subsampling method, which outperforms uniform subsampling method in terms of MSE; (3) we provide a method to approximate the A-optimal subsampling probabilities, since the running time of the A-optimal subsampling probabilities is the same as the full sample U-statistics; (4) we get the limiting distribution of …

Postsecondary Stem Paths Of High-Achieving Students In Math And Science: A Longitudinal Multilevel Investigation Of Their Selection And Persistence, Soohyun Yi

Open Access Dissertations

This study used a quantitative approach to investigate high-school students’ talent-development pathways in STEM from 10th through 12th grades and for 8 years thereafter. The purpose of this study was to longitudinally investigate three important choices and accomplishments on the STEM talent development trajectory: a) selecting a STEM major in college; b) persisting with the STEM major until graduation; and c) selecting a career in STEM after college graduation. Given that students with gifts and talents are more likely to persist and succeed in STEM fields than average achievers, and understanding their unique needs may be the first important task …

A Comprehensive Analysis Of Estimating Land Use Change Emissions Induced By Global Aviation Biofuels Production Using Economic Equilibrium Models, Xin Zhao

Open Access Dissertations

This dissertation is comprised of three independent but closely related essays, which provide new insights on estimating biofuels induced land use (ILUC) change and related emissions from distinct perspectives. The first essay in this dissertation developed the framework for estimating aviation biofuels induced land use change emissions using GTAP-BIO and its coupled emission model, AEZ-EF. We translate International Energy Agency (IEA) projections into appropriate shock sizes by region and pathway. We make modifications in GTAP-BIO to introduce the aviation biofuels pathways and update AEZ-EF based on new data. Twelve aviation biofuels pathways, produced using four technologies including Hydroprocessed Esters and …

Random Weighting Approach In Nonlinear And Hierarchical Regression Models, Yue Zhang

Open Access Dissertations

Nonlinear regression models with random and fixed effects are commonly used to analyze repeated measures data. Such data, consisting of repeated measurements taken on several individuals, typically arise in biological and biomedical applications amongst many other applications. The standard two-stage estimation (STS) method is intuitive and simple to implement in such circumstance, but the main difficulty is that not much is available on the sampling distribution of the resulting parameters estimates. In this work, we develop re-sampled versions of the least squares estimators (LSE) of the parameters in nonlinear regression as well as hierarchical nonlinear regression models. The approach we …

Adaptive Communication For Wireless Massive Mimo Systems, Ahmed A. Ibrahim

Open Access Dissertations

The demand for high data rates in wireless communications is increasing rapidly. One way to provide reliable communication with increased rates is massive multiple-input multiple-output (MIMO) systems where a large number of antennas is deployed. We analyze three systems utilizing a large number of antennas to provide enhancement in the performance of wireless communications. First, we consider a general form of spatial modulation (SM) systems where the number of transmitted data streams is allowed to vary and we refer to it as generalized spatial modulation with multiplexing (GSMM). A Gaussian mixture model (GMM) is shown to accurately model the transmitted …