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An Approach To Near Field Data Selection In Radio Frequency Identification, Robert D. Winkworth Jan 2015

An Approach To Near Field Data Selection In Radio Frequency Identification, Robert D. Winkworth

Open Access Dissertations

Personal identification is needed in many civil activities, and the common identification cards, such as a driver's license, have become the standard document de facto. Radio frequency identification has complicated this matter. Unlike their printed predecessors, contemporary RFID cards lack a practical way for users to control access to their individual fields of data. This leaves them more available to unauthorized parties, and more prone to abuse. Here, then was undertaken a means to test a novel RFID card technology that allows overlays to be used for reliable, reversible data access settings. Similar to other proposed switching mechanisms, it offers …

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Using Real Options Theory To Enhance Highway Asset Intervention Scheduling, Nathee Athigakunagorn Jan 2015

Using Real Options Theory To Enhance Highway Asset Intervention Scheduling, Nathee Athigakunagorn

Open Access Dissertations

Highway agencies have a fiduciary responsibility for cost-effective upkeep of highway assets worth trillions of dollars. A critical aspect of this stewardship is the ability to make informed decisions regarding the scheduling of interventions geared to enhance infrastructure capacity and structural integrity or to maintain a state of good repair. Development of such schedules which are time-based or condition-based, often proceeds with the implicit assumption that a certain asset-related parameter of volatility will continue to follow a certain pattern on the basis of observed past trends. However, given the uncertain nature of the asset environment, it is often the case …

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Influence Of Social Cognitive Variables On The Career Exploratory Behaviors Of African American Undergraduate Stem-Intensive Agricultural Sciences Majors At Historically Black Land-Grant Institutions, Qi Ding Jan 2015

Influence Of Social Cognitive Variables On The Career Exploratory Behaviors Of African American Undergraduate Stem-Intensive Agricultural Sciences Majors At Historically Black Land-Grant Institutions, Qi Ding

Open Access Dissertations

Without question, racial and ethnic minority groups are playing more significant roles in American society. However, there still remains a lack of diversity within the STEM workforce, especially within agricultural sciences disciplines. More problematic is the fact that low numbers of African Americans are employed in the agricultural sciences workforce. This study extends the use of Social Cognitive Career Theory by exploring how person, contextual and cognitive factors interplay to influence the career goals and career exploratory behaviors of African American college students pursuing STEM-intensive agricultural sciences majors. Instruments were selected to measure various components of the SCCT framework, focusing …

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Imaging Specific Absorption Rate With Mr Thermometry Using Paramagnetic Lanthanide Complexes And In Vivo Gaba Mr Spectroscopy In Movement Disorders, Shalmali Dharmadhikari Jan 2015

Imaging Specific Absorption Rate With Mr Thermometry Using Paramagnetic Lanthanide Complexes And In Vivo Gaba Mr Spectroscopy In Movement Disorders, Shalmali Dharmadhikari

Open Access Dissertations

Magnetic Resonance Imaging (MRI) is a popular imaging modality due to its ability to provide excellent soft tissue contrast without exposure to ionizing radiation. It can be used for temperature monitoring (thermometry) as well as for assessing the biochemistry in vivo (MRS). This dissertation focuses separately on the development, application and quantitation issues of these two aspects of MRI.

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Probabilistic Models For Droughts: Applications In Trigger Identification, Predictor Selection And Index Development, Meenu Ramadas Jan 2015

Probabilistic Models For Droughts: Applications In Trigger Identification, Predictor Selection And Index Development, Meenu Ramadas

Open Access Dissertations

The current practice of drought declaration (US Drought Monitor) provides a hard classification of droughts using various hydrologic variables. However, this method does not yield model uncertainty, and is very limited for forecasting upcoming droughts. The primary goal of this thesis is to develop and implement methods that incorporate uncertainty estimation into drought characterization, thereby enabling more informed and better decision making by water users and managers. Probabilistic models using hydrologic variables are developed, yielding new insights into drought characterization enabling fundamental applications in droughts.

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The Separation Of Two Different Sized Particles Via Droplet Evaporation, Nicole Raley Devlin Jan 2015

The Separation Of Two Different Sized Particles Via Droplet Evaporation, Nicole Raley Devlin

Open Access Dissertations

An evaporating droplet with different sized particles was examined both computationally and experimentally. During evaporation, particles can naturally separate into concentric rings by size with one ring per particle size. The objective of this investigation was to determine factors that contribute to this separation process.

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Low-Cost Structured-Light 3d Capture System Design, Jing Dong Jan 2015

Low-Cost Structured-Light 3d Capture System Design, Jing Dong

Open Access Dissertations

To date, three-dimensional measurement is a very important and popular topic in computer vision. Most of the 3D capture products currently in the market are high-end and pricey. They are not targeted for consumers, but rather for research, medical, or industrial usage. Very few aim to provide a solution for home and small business applications. Our goal is to fill in this gap by only using low-cost components to build a 3D capture system that can satisfy the needs of this market segment. In our research, we present a low-cost 3D capture system based on the structured-light method. The system …

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Enabling New Functionally Embedded Mechanical Systems Via Cutting, Folding, And 3d Printing, Wei Gao Jan 2015

Enabling New Functionally Embedded Mechanical Systems Via Cutting, Folding, And 3d Printing, Wei Gao

Open Access Dissertations

Traditional design tools and fabrication methods implicitly prevent mechanical engineers from encapsulating full functionalities such as mobility, transformation, sensing and actuation in the early design concept prototyping stage. Therefore, designers are forced to design, fabricate and assemble individual parts similar to conventional manufacturing, and iteratively create additional functionalities. This results in relatively high design iteration times and complex assembly strategies.

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A Bio-Inspired Self-Healing Polymer System For Sustainable Plastics, Michael Laird Johnston Jan 2015

A Bio-Inspired Self-Healing Polymer System For Sustainable Plastics, Michael Laird Johnston

Open Access Dissertations

Studying how marine organisms make tough biologic materials that autonomously heal allows us to integrate this biological self-healing motif into synthetic biomimetic polymers. These types of polymers will be used to develop components with greater fatigue life and toughness, promoting greater resource sustainability by reducing plastic consumption. The amino acid 3,4-dihydroxyphenylalanine (DOPA) grants marine mussels the ability to strongly affix themselves to the rocks under water by forming strong reversible bonds with their environment. Poly[(3,4-dihydroxystyrene)-co-styrene)] (P[3,4-DHS-S]) is a synthetic polymer mimic of DOPA with chemical structure similar to polystyrene (PS) with a potential self-healing mechanism. This intrinsic self-healing mechanism works …

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Data Representation Methods For Environmentally Conscious Product Design, Devarajan Ramanujan Jan 2015

Data Representation Methods For Environmentally Conscious Product Design, Devarajan Ramanujan

Open Access Dissertations

The challenge of holistically integrating environmental sustainability considerations with design decision-making requires novel representations for design and sustainability-related data that allow designers to understand correlations among them. Challenges such as (1) lack of suitable data & information models, (2) methods that simultaneously consider environmental sustainability as well as design constraints, and (3) uncertainty models for characterizing subjectivity in environmental sustainability-based decision making, pose serious impediments towards this goal.

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Modular Human-In-The-Loop Design Framework Based On Human Factors, Hasan Onan Demirel Jan 2015

Modular Human-In-The-Loop Design Framework Based On Human Factors, Hasan Onan Demirel

Open Access Dissertations

Human-in-the-loop design framework introduced in this dissertation utilizes Digital Human Modeling (DHM) to incorporate Human Factors Engineering (HFE) design principles early in design process. It embodies scientific methods (e.g., mathematics) and artistic approaches (e.g., visualization) to assess human well-being and overall system performance. This framework focuses not only on ergonomics assessments but also actual design process including, but not limited to, concept development, structural integrity and digital prototyping. It addresses to three major limitations found in HFE literature and practices:

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Profiles Of Patricia Tries, Abram Magner Jan 2015

Profiles Of Patricia Tries, Abram Magner

Open Access Dissertations

Digital trees are data structures that represent sets of strings according to their shared prefix structure.

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The Relationship Between Acoustic Features Of Second Language Speech And Listener Evaluation Of Speech Quality, Mengxi Lin Jan 2015

The Relationship Between Acoustic Features Of Second Language Speech And Listener Evaluation Of Speech Quality, Mengxi Lin

Open Access Dissertations

Second language (L2) speech is typically less fluent than native speech, and differs from it phonetically. While the speech of some L2 English speakers seems to be easily understood by native listeners despite the presence of a foreign accent, other L2 speech seems to be more demanding, such that listeners must expend considerable effort in order to understand it. One reason for this increased difficulty may simply be the speaker’s pronunciation accuracy or phonetic intelligibility. If a L2 speaker’s pronunciations of English sounds differ sufficiently from the sounds that native listeners expect, these differences may force native listeners to work …

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Finite Element Analysis Of The Equine Distal Limb Transfixation Cast, Timothy B. Lescun Jan 2015

Finite Element Analysis Of The Equine Distal Limb Transfixation Cast, Timothy B. Lescun

Open Access Dissertations

Lescun, Timothy B. Ph.D., Purdue University, December 2015. Finite Element Analysis of the Equine Distal Limb Transfixation Cast. Major Professors: Gert Breur and Eric Nauman.

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Analysis Of Models For Curvature Driven Motion Of Interfaces, Drew Swartz Jan 2015

Analysis Of Models For Curvature Driven Motion Of Interfaces, Drew Swartz

Open Access Dissertations

Interfacial energies frequently appear in models arising in materials science and engineering.

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A Variable-Structure Variable-Order Simulation Paradigm For Power Electronic Circuits, Anandakumar Subbiah Jan 2015

A Variable-Structure Variable-Order Simulation Paradigm For Power Electronic Circuits, Anandakumar Subbiah

Open Access Dissertations

Solid-state power converters are used in a rapidly growing number of applications including variable-speed motor drives for hybrid electric vehicles and industrial applications, battery energy storage systems, and for interfacing renewable energy sources and controlling power flow in electric power systems. The desire for higher power densities and improved efficiencies necessitates the accurate prediction of switching transients and losses that, historically, have been categorized as conduction and switching losses. In the vast majority of analyses, the power semiconductors (diodes, transistors) are represented using simplified or empirical models. Conduction losses are calculated as the product of circuit-dependent currents and on-state voltage …

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Multi-Level Systems Modeling And Optimization, Shreyas Vathul Subramanian Jan 2015

Multi-Level Systems Modeling And Optimization, Shreyas Vathul Subramanian

Open Access Dissertations

This research combines the disciplines of system-of-systems (SoS) modeling, platform-based design, optimization and evolving design spaces to achieve a novel capability for designing solutions to key aeronautical mission challenges. A central innovation in this approach is the confluence of multi-level modeling (from sub-systems to the aircraft system to aeronautical system-of-systems) in a way that coordinates the appropriate problem formulations at each level and enables parametric search in design libraries for solutions that satisfy level-specific objectives. The work here addresses the topic of SoS optimization and discusses problem formulation, solution strategy, the need for new algorithms that address special features of …

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Embodied Interactions For Spatial Design Ideation: Symbolic, Geometric, And Tangible Approaches, Fnu Vinayak Jan 2015

Embodied Interactions For Spatial Design Ideation: Symbolic, Geometric, And Tangible Approaches, Fnu Vinayak

Open Access Dissertations

Computer interfaces are evolving from mere aids for number crunching into active partners in creative processes such as art and design. This is, to a great extent, the result of mass availability of new interaction technology such as depth sensing, sensor integration in mobile devices, and increasing computational power. We are now witnessing the emergence of maker culture that can elevate art and design beyond the purview of enterprises and professionals such as trained engineers and artists. Materializing this transformation is not trivial; everyone has ideas but only a select few can bring them to reality. The challenge is the …

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Prime Saturations And Rees Algebras Of Almost Linearly Presented Ideals, Jacob Boswell Jan 2015

Prime Saturations And Rees Algebras Of Almost Linearly Presented Ideals, Jacob Boswell

Open Access Dissertations

Let I be a height two perfect ideal in the polynomial ring k[x1, ..., xd] satisfying the Gd condition. Suppose I admits a homogeneous presentation matrix composed of linear columns except for one column of degree n. In this setting, we give two descriptions of the ideal A defining the Rees algebra Rees(I) and if in addition I is generated by d+1 elements, we give an explicit generating set for A.

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Stochastic Modeling Of Limit Order Books: Convergence Of The Price Process, Simulation And Applications, Jonathan Allan Chavez Casillas Jan 2015

Stochastic Modeling Of Limit Order Books: Convergence Of The Price Process, Simulation And Applications, Jonathan Allan Chavez Casillas

Open Access Dissertations

In the past two decades, electronic limit order books (LOBs) have become the most important mechanism through which securities are traded. A LOB contains the current supply and demand of a security at different prices and it can be modeled as a random, state-dependent, and high-dimensional system since typically a great number of orders are placed at many different prices at a millisecond time scale. These features lead to an inherent mathematical complexity which is extremely hard to describe in a tractable manner. Thus, depending on the purpose, different models have been proposed to capture specific properties of the underlying …

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Effects Of High-Protein And High-Fiber Breakfasts On Preschoolers' Feelings Of Fullness, Diet Quality And Memory, Mary Catherine Brauchla Jan 2015

Effects Of High-Protein And High-Fiber Breakfasts On Preschoolers' Feelings Of Fullness, Diet Quality And Memory, Mary Catherine Brauchla

Open Access Dissertations

ABSTRACT

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Conversation Analysis Of Engineering Parents' Occupational Knowledge, Attitudes And Beliefs, Brianna Louise Dorie Brinkman Jan 2015

Conversation Analysis Of Engineering Parents' Occupational Knowledge, Attitudes And Beliefs, Brianna Louise Dorie Brinkman

Open Access Dissertations

Broadening participation from a diverse set of individuals is one of the central tenets of engineering education research. Interest in a potential occupation is influenced by knowledge and familiarity as a child reaches adolescence. However, studies have shown that most children have limited information regarding engineers, and this lack of knowledge can often persist into adulthood. Parents are the predominant source of occupational information for young children, and researchers hypothesize that parents socialize their children to be predisposed to their own occupation through informal interactions such as conversations. This is highly evident in the phenomena of occupational inheritance that is …

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Supercuspidal Representations Arising From Stable Vectors, Britain Cox Jan 2015

Supercuspidal Representations Arising From Stable Vectors, Britain Cox

Open Access Dissertations

For a reductive group $G$ over a $p$-adic field $k$, one may grade the associated Lie algebra $\g$ by an automorphism of order $m$. It has been shown that stable vectors $v\in\g_{a}$ arise only when $a$ is coprime to $m$. Given a stable vector $v\in\g_{a}$, we construct packets of supercuspidal representations $\{\pi_{v,\rho}\}$ as well as discrete Langlands parameters $\varphi_{v}$. Both the parameter and representations are of depth $a/m$. We further show that for a fixed vector, $\pi_{v,\rho}$ and $\varphi_{v}$ satisfy both sides of the formal degree conjecture.

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On Several Efficient Algorithms For Some Partial Differential Equations, Hee Jun Choi Jan 2015

On Several Efficient Algorithms For Some Partial Differential Equations, Hee Jun Choi

Open Access Dissertations

ABSTRACT

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A Phenomenographic Study Of How Aerospace Engineers Experience Uncertainty When Making Design Decisions, Antonette T. Cummings Jan 2015

A Phenomenographic Study Of How Aerospace Engineers Experience Uncertainty When Making Design Decisions, Antonette T. Cummings

Open Access Dissertations

This study investigated the qualitatively different ways in which engineers working in aerospace-related industries experience uncertainty as they make design decisions. This study provides insight on how engineers increase their ability to manage various forms of uncertainty as they design large scale complex engineered systems. The results of this study are valuable for understanding learning trajectories of engineers beyond their academic experiences and for linking the professional and technical skills in industry to the undergraduate engineering learning experience.

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Effects Of Collaboration And Isomorphic Models On Transfer: An L2 Writing Investigation, Dennis Mitchell Koyama Jan 2015

Effects Of Collaboration And Isomorphic Models On Transfer: An L2 Writing Investigation, Dennis Mitchell Koyama

Open Access Dissertations

How can feedback become a productive resource for students? Much of the research investigating the role of feedback in second language (L2) writing has set out to find an answer to this question. Based on the principle that feedback is given to students as a means of providing useful information to improve their writing (Bitchener, 2008, 2009; Hanaoka & Izumi, 2012), the discussion on feedback includes the idea that learners will transfer knowledge from feedback to improve subsequent writing (Hyland, 1998; Storch & Wigglesworth, 2010). When learners apply feedback to their subsequent writing, they are using collected knowledge, which is …

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Undergraduate Engineering Students’ Understanding Of Complex Circuit Concepts: An Investigation Of The Intersection Of Students’ Prior Knowledge, Design Of Learning Environments And The Nature Of The Content, Nicole Pitterson Jan 2015

Undergraduate Engineering Students’ Understanding Of Complex Circuit Concepts: An Investigation Of The Intersection Of Students’ Prior Knowledge, Design Of Learning Environments And The Nature Of The Content, Nicole Pitterson

Open Access Dissertations

Research focused on increasing students’ conceptual understanding of electric circuits discuss this concept as difficult to not only teach but for students to grasp. This difficulty has been attributed to the fact that students tend to hold inaccurate pre-conceptions of electricity which becomes problematic as the level of complexity increases from the most basic to more advanced circuit concepts. The combination of inaccurate and inadequate prior knowledge has the potential to prevent students from being able to assimilate new material they come in contact with when instructed about electric circuit concepts in formal settings. Often times, students’ inability to associate …

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Decentralized Algorithms For Nash Equilibrium Problems – Applications To Multi-Agent Network Interdiction Games And Beyond, Harikrishnan Sreekumaran Jan 2015

Decentralized Algorithms For Nash Equilibrium Problems – Applications To Multi-Agent Network Interdiction Games And Beyond, Harikrishnan Sreekumaran

Open Access Dissertations

Nash equilibrium problems (NEPs) have gained popularity in recent years in the engineering community due to their ready applicability to a wide variety of practical problems ranging from communication network design to power market analysis. There are strong links between the tools used to analyze NEPs and the classical techniques of nonlinear and combinatorial optimization. However, there remain significant challenges in both the theoretical and algorithmic analysis of NEPs. This dissertation studies certain special classes of NEPs, with the overall purpose of analyzing theoretical properties such as existence and uniqueness, while at the same time proposing decentralized algorithms that provably …

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A Techno-Economic Investigation Of Advanced Vehicle Technologies And Their Impacts On Fuel Economy, Emissions, And The Future Fleet, Richard A. Simmons Jan 2015

A Techno-Economic Investigation Of Advanced Vehicle Technologies And Their Impacts On Fuel Economy, Emissions, And The Future Fleet, Richard A. Simmons

Open Access Dissertations

A more sustainable transportation energy future for society is the principal motivation of this dissertation. The central purpose of this work is to investigate vehicle technologies that contribute to fuel and emissions reductions while preserving consumer choice, and to evaluate their technological performance and economic practicability as essential aspects of meeting aspirational targets and regulatory requirements associated with the future vehicle fleet.

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Understanding Co-Teaching And Related Self-Efficacy Change In Student Teachers Who Co-Teach, Krista Zartman Jan 2015

Understanding Co-Teaching And Related Self-Efficacy Change In Student Teachers Who Co-Teach, Krista Zartman

Open Access Dissertations

This study’s purpose was twofold. First, I sought to understand and document the experience of co-teaching as a student teacher as it is currently being conducted by universities in the State of Indiana. Secondly, I desired to understand how the documented experiences impact a pre-service student teacher’s developing sense of self-efficacy related to teaching. Therefore, this work presents the results of a mixed-methods study addressing the research questions:

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