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Engineering Play: Exploring Associations With Executive Function, Mathematical Ability, And Spatial Ability In Preschool, Zachary Samuel Gold Dec 2017

Engineering Play: Exploring Associations With Executive Function, Mathematical Ability, And Spatial Ability In Preschool, Zachary Samuel Gold

Open Access Dissertations

Engineering play is a new perspective on preschool education that views constructive play as an engineering design process that parallels the way engineers think and work when they develop engineered solutions to human problems (Bairaktarova, Evangelou, Bagiati, & Brophy, 2011). Early research from this perspective supports its use in framing play as a key learning context. However, no research to date has examined associations between engineering play and other factors linked with early school success, such as executive function, mathematical ability, and spatial ability. Additionally, more research is needed to further validate a new engineering play observational measure. This study …

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Imaging Cholesterol Metabolism And Trafficking By Stimulated Raman Scattering Microscopy, Hyeon Jeong Lee Dec 2017

Imaging Cholesterol Metabolism And Trafficking By Stimulated Raman Scattering Microscopy, Hyeon Jeong Lee

Open Access Dissertations

Cholesterol is an essential component of mammalian cells which is tightly regulated. However, our understanding of cholesterol transport and metabolism is still incomplete, partly due to lack of suitable tools for studying cholesterol dynamics in living cells and organisms with spatio-temporal information. My dissertation work applied spectroscopic imaging of cholesterol in human tissues, living cells, and model organisms to unravel new insights of cholesterol metabolism and trafficking. Using stimulated Raman spectroscopic analysis of lipid droplets in human prostate cancer patient tissues, we observed an aberrant accumulation of cholesteryl ester in metastatic lesions. Inhibition of cholesterol esterification in prostate cancer cells …

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Global Optimization Of Large-Scale Complex Nonlinear Systems: Algorithms And Applications, Jianfeng Liu Dec 2017

Global Optimization Of Large-Scale Complex Nonlinear Systems: Algorithms And Applications, Jianfeng Liu

Open Access Dissertations

Many practical applications involving large complex systems are naturally formulated as mixed-integer nonlinear programming (MINLP) problems. These optimization problems are inherently large-scale and non-convex, and can be extremely difficult to solve. Efficient algorithms, especially global solution strategies, for MINLP problems play important roles in many real-world applications. Although a number of optimization tools have been developed for general MINLP problems, their performance may vary significantly on different problem instances. Moreover, computational experience has suggested that for MINLP problems with certain particular properties, customized algorithms can significantly outperform general MINLP solvers. In this thesis, we focus on developing and applying problem-specific …

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A Study Of Singularities In Drops And Bubbles Under The Influence Of Non- Newtonian Surface And Bulk Rheology, Pritish M. Kamat Dec 2017

A Study Of Singularities In Drops And Bubbles Under The Influence Of Non- Newtonian Surface And Bulk Rheology, Pritish M. Kamat

Open Access Dissertations

Fluid-fluid interfaces are incredibly complex physical structures. Imbued with an excess energy—or in mechanical terms, a surface tension σ—these interfaces are considerably influential at small scales of droplets and bubbles, and in these systems, they are responsible for a plethora of beautiful and dramatically complex phenomena. The study of these interfacial phenomena, the so-called ‘free surface flows’, lends itself to a variety of applications which are at once, as mundane as liquid dripping from a faucet or rain splashing over the windscreen of a car, and at the same time extremely useful in industry and scientific analysis – some examples …

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Developing And Testing A K-12 Engineering Epistemic Frame To Uncover Engineering In The Interactions Of A High School Summer Session, Tamecia Raishuan Jones Dec 2017

Developing And Testing A K-12 Engineering Epistemic Frame To Uncover Engineering In The Interactions Of A High School Summer Session, Tamecia Raishuan Jones

Open Access Dissertations

Educational reform has expanded K-12 standards to include engineering. Not only will K-12 teachers have to be trained to teach engineering concepts, but assessments must evolve to reflect the various aspects of engineering. Engineering as a profession is expressed via multiple dimensions of an epistemic frame, such as skills, knowledge, identity, values, and epistemology, but many of these elements are not measured in K-12 formal and informal spaces. In a summer session of a college preparatory program, a research project revealed that although students had design journals, storyboards, and traditional assessments, the in situ video recordings captured decisions, evolution of …

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Wavetda: Bayesian Statistics, Wavelets And Topological Data Analysis To Title Assess Statistical Shape, Patrick S. Medina Dec 2017

Wavetda: Bayesian Statistics, Wavelets And Topological Data Analysis To Title Assess Statistical Shape, Patrick S. Medina

Open Access Dissertations

Advanced imaging and scanning technologies are providing an abundance of shape-based data that require novel approaches to understand the factors that generate them. This is especially true in modern agricultural practices where large quantities of highly detailed morphometric data are collected and used for studying genetic associations. Toward this end there is an immediate need for efficient algorithms that extract relevant geometric information from images in a form that can be used within a statistical framework. Topological Data Analysis (TDA) has shown to be both fast and effective for studying complex shapes, and can simultaneously reduce dimensionality into simpler topological …

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Teachers' Perceptions Of The Impact Of Culturally Responsive Pedagogy On The Student Learning Outcomes Of African American Male Students., Dennisha M. Murff Dec 2017

Teachers' Perceptions Of The Impact Of Culturally Responsive Pedagogy On The Student Learning Outcomes Of African American Male Students., Dennisha M. Murff

Open Access Dissertations

The purpose of this qualitative study was to explore teachers’ perceptions of the impact of implementing culturally responsive pedagogical practices on the student learning outcomes of African-American male students. The secondary purpose was to identify teachers’ perceptions of the culturally responsive pedagogy strategies needed in the classroom to address the diverse needs of African-American male students. The case study approach allowed for additional insight into the potential impact of culturally responsive pedagogical practices on the student learning outcomes of African-American male students in the elementary school setting. Data were collected from a large, diverse elementary school in an urban school …

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Investigation Of Pore Formation In Lipid Bilayer By Antimicrobial Peptides, Yuan Lyu Dec 2017

Investigation Of Pore Formation In Lipid Bilayer By Antimicrobial Peptides, Yuan Lyu

Open Access Dissertations

As more and more microbes develop resistance to conventional antibiotics and the decline in the approval of new antibiotics in recent years, there is an increasing need for research on identification and design of new therapeutic alternatives. As a result, antimicrobial peptides (AMPs) are becoming one of the most promising alternative options to target pathogens without developing resistance. It is known that AMPs inactivate microorganisms by forming transmembrane pores in cell membrane through adsorption and aggregation. Understanding the detailed mechanism of inactivation by AMPs is necessary for developing new agent for antimicrobial treatment. This study mainly investigates antimicrobial peptides from …

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Geophysical Signatures Of Fracture Mechanisms, Anahita Modiriasari Dec 2017

Geophysical Signatures Of Fracture Mechanisms, Anahita Modiriasari

Open Access Dissertations

Fractures and discontinuities have a significant influence on the mechanical and hydraulic properties of brittle materials such as rock. The prediction of rock mass behavior requires information on the location and character of the initiation, propagation, and coalescence of new and pre-existing cracks. Methods based on the interpretation of seismic waves are of great interest because the waves can be used to probe internal damage in rock. The objective of this research is to characterize crack initiation, propagation, and coalescence inside rock using wave propagation. Digital image correlation (DIC) was employed to investigate crack evolution on the surface of rock …

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Experimental Demonstration Of Engineered Dipole-Dipole Interactions In Nanophotonic Environments, Ward D. Newman Dec 2017

Experimental Demonstration Of Engineered Dipole-Dipole Interactions In Nanophotonic Environments, Ward D. Newman

Open Access Dissertations

Zero point fluctuations of the electromagnetic radiation field have profound effects on the electronic states of atoms and molecules. For example, vacuum fluctuations of the photonic radiation field stimulate the spontaneous decay of excited states of atoms (spontaneous emission), shift atomic energy levels (Lamb Shift), and allow nearby atoms and molecules to couple via dipole-dipole interactions (van der Waals interactions, Casimir effect, super radiance, F¨orster resonance energy transfer). The control and modification of vacuum fluctuations has been a long-standing theme in quantum engineering as one can then truly control single photon emission and alter dipole-dipole interactions spatial scaling with distance. …

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Carbon Taxes, Forest Carbon Sequestration, Climate Induced Land Yield Changes, And Their Interactions, Luis Moisés Peña-Lévano Dec 2017

Carbon Taxes, Forest Carbon Sequestration, Climate Induced Land Yield Changes, And Their Interactions, Luis Moisés Peña-Lévano

Open Access Dissertations

This dissertation is comprised of three essays that evaluate the economic benefits and costs of mitigating climate change at the global scale. Each essay relies on computable general equilibrium (CGE) modeling. The first essay evaluates the economic and environmental interactions among climate change, agriculture, forest carbon sequestration and food security. It addresses changes in land use, commodity and food prices, economic welfare, emission reductions, among other economic factors. This study finds that an aggressive sequestration subsidy can represent a threat for food security due to the land competition between agriculture and forestry. Likewise, the results suggest that there are benefits …

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Laser-Assisted Processing Of Multilayer Films For Inexpensive And Flexible Biomedical Microsystems, Rahim Rahimi Dec 2017

Laser-Assisted Processing Of Multilayer Films For Inexpensive And Flexible Biomedical Microsystems, Rahim Rahimi

Open Access Dissertations

Flexible/stretchable electronics offer ideal properties for emerging health monitoring devices that can seamlessly integrate with the soft, curvilinear, and dynamic surfaces of the human body. The resulting capabilities have allowed novel devices for monitoring physiological parameters, improving surgical procedures, and human-machine interfaces. While the attractiveness of these devices are indubitable, their fabrication by conventional cleanroom techniques makes them expensive and incompatible with rapid large-scale (e.g., roll-to-roll) production. The purpose of this research is to develop inexpensive fabrication technologies using low-cost commercial films such as polyimide, paper, and metalized paper that can be utilized for developing various flexible/stretchable physical and chemical …

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Process Intensification Through Spherical Crystallization: Novel Experimental And Modeling Approaches, Ramon Peña Dec 2017

Process Intensification Through Spherical Crystallization: Novel Experimental And Modeling Approaches, Ramon Peña

Open Access Dissertations

Process intensification is defined as the use of innovative techniques and technologies to create sustainable solutions to industrial production difficulties. Continuous spherical crystallization is a process intensification technique that could resolve production issues for pharmaceutical and solids processing industries, consequently, allowing for the integration of upstream and downstream manufacturing units. Spherical crystallization is carried out through emulsion based crystallization and/or agglomeration in suspension of fine crystals to produce aggregates of improved bulk and micromeritic properties. The advantages of spherical crystallization include: (i) replacing downstream particle correction units (i.e., milling, granulation), (ii) providing control of crystalline properties by decoupling crystallization and …

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Determining Variation In Virulence, Persistence, And Stress Tolerance Among Salmonella Enterica And Listeria Monocytogenes From Food And Food-Associated Environments, Andrea J. (Ray) Etter Dec 2017

Determining Variation In Virulence, Persistence, And Stress Tolerance Among Salmonella Enterica And Listeria Monocytogenes From Food And Food-Associated Environments, Andrea J. (Ray) Etter

Open Access Dissertations

The U.S. food industry employs multiple strategies to prevent foodborne illness including the use of antimicrobials, sanitizers, and heat to reduce or eliminate pathogens in food products. However, Listeria monocytogenes and Salmonella enterica isolates have widely varying tolerance to common processing stresses. Additionally, both pathogens display considerable variation in virulence among serovars and strains. The goal of these studies was to characterize the range of virulence and persistence capabilities for L. monocytogenes and S. enterica isolates. To this end, we determined the prevalence of inlA mutations in L. monocytogenes collected from retail deli surfaces, and used PFGE to study the …

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Anisotropic Electron-Electron Interactions In Topological Insulators, Marius A. Radu Dec 2017

Anisotropic Electron-Electron Interactions In Topological Insulators, Marius A. Radu

Open Access Dissertations

HgTe forms a two-dimensional topological insulator when sandwiched between CdTe barriers for a HgTe layer wider than the critical thickness. In this study we derive single-particle interaction Hamiltonians describing the physics of these compounds by using k · p theory and extended Kane model. We include contributions from upper conduction bands with orbital states of p-symmetry that bring about the terms describing lack of inversion symmetry in host semiconductors. A crucial ingredient is hetero-interface contribution to intrinsic spin-orbit interactions that drives significant anticrossing gaps in spectra at zero wavevector, but results in a circle of spectral degeneracies at finite wavevectors. …

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Novel Strategies For The Multi-Level, Online Optimization And Control Of Batch Operations Under Uncertainty, Francesco Rossi Dec 2017

Novel Strategies For The Multi-Level, Online Optimization And Control Of Batch Operations Under Uncertainty, Francesco Rossi

Open Access Dissertations

This thesis is focused on the development and application of innovative methods and algorithms for the multi-level, online optimization and control of batch processes under uncertainty. Specifically, it proposes novel solutions for the deterministic and stochastic dynamic optimization/optimal control of single batch operations and introduces new strategies for the integrated scheduling, dynamic optimization and optimal control of multi-unit/multi-step batch process. Moreover, it develops innovative approaches for the rapid estimation of the probability distribution of the uncertain parameters of dynamic process models from experimental measurements as well as new methodologies for selection of the optimal set of uncertain parameters in stochastic …

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A General Probabilistic Framework Combining Experiments And Simulations To Identify The Small Crack Driving Force, Andrea Rovinelli Dec 2017

A General Probabilistic Framework Combining Experiments And Simulations To Identify The Small Crack Driving Force, Andrea Rovinelli

Open Access Dissertations

Identifying the small fatigue crack (SFC) driving force of polycrystalline engineering alloys is instrumental in correlating the inherent microstructure variability and the scatter exhibited by SFC during the early stage of propagation. By utilizing synchrotron images of a SFC propagating through a beta-metastable titanium alloy a general framework to identify the SFC driving force is presented. FFT-based crystal plasticity simulations are then used to computed micromechanical quantities not available from the experiment. The experimental and simulation results are consolidated into a multimodal dataset which is sampled using physically based nonlocal data mining techniques. Sampled data are analyzed via a machine …

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Two Mathematics Teachers' Personal Practical Knowledge: Experiences Making Curriculum Within The 3d Inquiry Space, Elizabeth Suazo Flores Dec 2017

Two Mathematics Teachers' Personal Practical Knowledge: Experiences Making Curriculum Within The 3d Inquiry Space, Elizabeth Suazo Flores

Open Access Dissertations

This study is an effort to expand conceptualizations of mathematics teachers’ knowledge where teachers’ experiences are considered an important source of their knowledge. Using Schwab’s (1969, 1983) concept of curriculum and Dewey’s (1938) theory of experience as theoretical lenses, the researcher, a former secondary mathematics teacher, explored an eighth-grade mathematics teacher’s personal practical knowledge ([PPK], Elbaz, 1981, 1983). The mathematics aspect of this study was the emerging concept of area as students worked on a lesson involving real-world context. Field and research texts were constructed through narrative inquiry (Clandinin & Connelly, 2000). This study illustrates how under a four-year collaboration: …

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New Multi-Harmonic Techniques For Sensing Tip-Sample Interactions And Nanomechanical Material Property Mapping In Dynamic Atomic Force Microscopy, Nurul Huda Shaik Dec 2017

New Multi-Harmonic Techniques For Sensing Tip-Sample Interactions And Nanomechanical Material Property Mapping In Dynamic Atomic Force Microscopy, Nurul Huda Shaik

Open Access Dissertations

The Atomic Force Microscope (AFM) is a versatile tool for studying and characterizing materials at the micro-and nano-scales. The microcantilever designs used in AFM, as well as the experimental and theoretical approaches for quantitative material characterization, are now well developed and understood. However, there are still certain experimental conditions where the conventional design of these probes and the existing material characterization methods limit the applicability of the tool. The challenges associated with the probe design are addressed by integrating additional degrees of freedom into these probes that enabled modification of the eigen-structure of the probes as desired. Designing, fabricating and …

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Global Optimization Approach To The Labeling Of Airborne Lidar Point Clouds, Serkan Ural Dec 2017

Global Optimization Approach To The Labeling Of Airborne Lidar Point Clouds, Serkan Ural

Open Access Dissertations

Airborne LiDAR systems provide an unstructured 3D sampling of the objects on and above the ground. Building extraction has traditionally been among the most sought-after applications of airborne lidar topographic mapping along with digital elevation model generation. Extracting buildings from point clouds requires the labeling of the point cloud. Recent methods take advantage of the point properties calculated within a local neighborhood to achieve such labeling. Considering only the properties of individual points however, disregards spatial coherence. The relative change of point properties in the immediate surrounding of each point as well as spatial relationships between neighboring points need to …

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Coherent Radiation In Atomic Systems, Robert Tyler Sutherland Dec 2017

Coherent Radiation In Atomic Systems, Robert Tyler Sutherland

Open Access Dissertations

Over the last century, quantum mechanics has dramatically altered our understanding of light and matter. Impressively, exploring the relationship between the two continues to provide important insights into the physics of many-body systems. In this thesis, we add to this still growing field of study. Specifically, we discuss superradiant line-broadening and cooperative dipole-dipole interactions for cold atom clouds in the linear-optics regime. We then discuss how coherent radiation changes both the photon scattering properties and the excitation distribution of atomic arrays. After that, we explore the nature of superradiance in in intially inverted clouds of multi-level atoms. Finally, we explore …

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Micromechanics Based Failure Analysis Of Heterogeneous Materials, Hamsasew M. Sertse Dec 2017

Micromechanics Based Failure Analysis Of Heterogeneous Materials, Hamsasew M. Sertse

Open Access Dissertations

In recent decades, heterogeneous materials are extensively used in various industries such as aerospace, defense, automotive and others due to their desirable specific properties and excellent capability of accumulating damage. Despite their wide use, there are numerous challenges associated with the application of these materials. One of the main challenges is lack of accurate tools to predict the initiation, progression and final failure of these materials under various thermomechanical loading conditions. Although failure is usually treated at the macro and meso-scale level, the initiation and growth of failure is a complex phenomena across multiple scales. The objective of this work …

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Computational And Theoretical Study Of The Physical Constraints On Chemotaxis, Julien Varennes Dec 2017

Computational And Theoretical Study Of The Physical Constraints On Chemotaxis, Julien Varennes

Open Access Dissertations

Cell chemotaxis is crucial to many biological functions including development, wound healing, and cancer metastasis. Chemotaxis is the process in which cells migrate in response to chemical concentration gradients. Recent experiments show that cells are capable of detecting shallow gradients as small as a 1% concentration difference, and multicellular groups can improve on this by an additional order of magnitude. Examples from morphogenesis and metastasis demonstrate collective response to gradients equivalent to a 1 molecule difference in concentration across a cell body. While the physical constraints to cell gradient sensing are well understood, how the sensory information leads to cell …

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Autonomous Guidance Strategy For Spacecraft Formations And Reconfiguration Maneuvers, Theodore P. Wahl Dec 2017

Autonomous Guidance Strategy For Spacecraft Formations And Reconfiguration Maneuvers, Theodore P. Wahl

Open Access Dissertations

A guidance strategy for autonomous spacecraft formation reconfiguration maneuvers is presented. The guidance strategy is presented as an algorithm that solves the linked assignment and delivery problems. The assignment problem is the task of assigning the member spacecraft of the formation to their new positions in the desired formation geometry. The guidance algorithm uses an auction process (also called an “auction algorithm”), presented in the dissertation, to solve the assignment problem. The auction uses the estimated maneuver and time of flight costs between the spacecraft and targets to create assignments which minimize a specific “expense” function for the formation. The …

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Clustering And Segmentation With Application In Document Image Processing, Haitao Xue Dec 2017

Clustering And Segmentation With Application In Document Image Processing, Haitao Xue

Open Access Dissertations

In this dissertation, we introduce a set of algorithms for document image processing, which are in the research area of color clustering and binarization. Color quantization algorithms are used to select a small number of colors that can accurately represent the content of a particular image. In this research, we introduce a novel color quantization algorithm which is based on the minimization of a modifed Lp norm rather than the more traditional L2 norm associated with mean square error (MSE) [1]. We demonstrate that the Lp optimization approach has two advantages. First, it produces more accurate perceived quality results, especially …

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Optimization, Control And Operation Strategies For Distributed Energy Systems, Jie Xue Dec 2017

Optimization, Control And Operation Strategies For Distributed Energy Systems, Jie Xue

Open Access Dissertations

In this dissertation, the problem of optimal operation strategies and control for gas turbine based distributed energy systems (DES) is addressed using mathematical optimization methods and computational intelligence techniques. Detailed mathematical component models for the key components of the DES such as gas turbine power generator, heat exchanger, absorption chiller, photovoltaic and wind turbine, are developed to capture the important behavior of these components and their interactions with the overall DES. These models are used to develop integrated DES models for the purpose of optimization and control design. A multi-objective function considering the total system efficiency and operational cost is …

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Damage, Tension/Compression Asymmetry And Inferred Crack Growth In Fatigue Title Of Aluminum Alloys, Colin Young Dec 2017

Damage, Tension/Compression Asymmetry And Inferred Crack Growth In Fatigue Title Of Aluminum Alloys, Colin Young

Open Access Dissertations

The idea of a quantity D, which tracks the damage state of a material from 0 (virgin) to 1 (failed) is a well-established concept. In fatigue tests, where a given load cycle is repeated until failure, it is common to define damage D per cycle as the fraction of total life consumed per cycle, or 1/Nf. We begin by using Maximum Entropy method to develop a curve to model the life vs. load cycle relationship for a wrought aluminum alloy 2024-T351 in the low cycle fatigue range. The approach is novel in that the loading is described in terms in …

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Augmented Matrix Solvers For Dynamic Linear Systems Of Equations, Yu Hong Yeung Dec 2017

Augmented Matrix Solvers For Dynamic Linear Systems Of Equations, Yu Hong Yeung

Open Access Dissertations

In this dissertation, the problem of updating in real time the solution to a linear system of equations when a sequence of small changes is made to the data is considered. This problem arises in many computational science and engineering applications, and we consider two of them. The first is surgical simulations, where a simulator used to train surgeons needs to provide haptic feedback by updating the system ten to hundred times per second. The second is contingency analysis in the power grids, when their operators need to simulate a large number of scenarios to predict what could happen when …

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Scalable Bayesian Nonparametrics And Sparse Learning For Hidden Relationship Discovery, Shandian Zhe Dec 2017

Scalable Bayesian Nonparametrics And Sparse Learning For Hidden Relationship Discovery, Shandian Zhe

Open Access Dissertations

Real-world data often encompass hidden relationships, such as interactions between modes in multidimensional arrays (or tensors), subsets of features correlated to specifc responses, and associations between heterogeneous data sources. Uncovering these relationships is a key problem in machine learning and data mining, and relates to numerous applications ranging from information security to imaging genetics and to computational advertisement. However, to mine these relationships, we have to face several signifcant challenges. First, how can we design powerful models to capture the complicated, potentially highly nonlinear patterns in data? Second, how can we develop effcient model estimation algorithms to deal with real-world …

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Pattern-Based Systems Engineering (Pbse) - Product Lifecycle Management (Plm) Integration And Validation, Rajat Gupta Dec 2017

Pattern-Based Systems Engineering (Pbse) - Product Lifecycle Management (Plm) Integration And Validation, Rajat Gupta

Open Access Theses

Mass customization, small lot sizes, reduced cost, high variability of product types and changing product portfolio are characteristics of modern manufacturing systems during life cycle. A direct consequence of these characteristics is a more complex system and supply chain. Product lifecycle management (PLM) and model based system engineering (MBSE) are tools which have been proposed and implemented to address different aspects of this complexity and resulting challenges. Our previous work has successfully implemented a MBSE model into a PLM platform. More specifically, Pattern based system engineering (S* pattern) models of systems are integrated with TEAMCENTER to link and interface system …

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