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Impact Of Disinfectant Type, Concentration, And Contact Time On Bactericidal Efficacy Against Healthcare-Associated Pathogens, Alyssa M. West May 2018

Impact Of Disinfectant Type, Concentration, And Contact Time On Bactericidal Efficacy Against Healthcare-Associated Pathogens, Alyssa M. West

Open Access Theses

Transmission of healthcare-associated infections caused by antibiotic- and multi-drug resistant (MDR) pathogens, (e.g. Methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa) are a major concern in patient care facilities. Disinfectant usage is critical to control and prevent pathogen transmission, yet the relationships among strain, disinfectant type, contact time, and concentration are not well-characterized. Furthermore, many healthcare facilities use pre-wetted disinfectant towelettes for surface disinfection, as they are an easy-to-use solution. Yet, there is a limited consensus as to whether a surface needs to remain wet for the full label contact time after the disinfectant towelette has been used, in order for complete …

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Police In Crisis, Communities In Conflict: A Computer-Aided Model For Analyzing Reconciliatory Tone, Cody Blake Wilson May 2018

Police In Crisis, Communities In Conflict: A Computer-Aided Model For Analyzing Reconciliatory Tone, Cody Blake Wilson

Open Access Theses

Crises triggered by the officer-involved shootings of Black men were compounded by poor initial press conferences led by police and city leaders. However, these moments are ripe for the use of a reconciliatory tone, as speakers find themselves not only responding to the present crisis, but a history of crises between police and communities of color. Three recent, prominent cases are chosen as case studies for inquiry: the case of Ferguson Police Department, North Charleston Police Department, and Tulsa Police Department. A reconciliatory tone model using the DICTION text analysis program and conceptual network analysis is used alongside qualitative review …

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Mixing By Cutting And Shuffling A Line Segment: The Effect Of Incorporating Diffusion, Mengying Wang May 2018

Mixing By Cutting And Shuffling A Line Segment: The Effect Of Incorporating Diffusion, Mengying Wang

Open Access Theses

Dynamical systems are commonly used to model mixing in fluid and granular flows. We consider a one-dimensional discontinuous dynamical system model (termed “cutting and shuffling” of a line segment), and we present a comprehensive computational study of finite-time mixing. The properties of the system depend on several parameters in a sensitive way, and the effect of each parameter is examined. Space-time and waterfall plots are introduced to visualize the mixing process with different mixing protocols without diffusion, showing a variety of distinct and complex behaviors in this “simple” dynamical system. To improve the mixing efficiency and avoid pathological cases, we …

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Cover Crop And No-Tillage Impacts On Soil Health And Soil Nitrogen In Indiana, Jennifer D. Woodyard May 2018

Cover Crop And No-Tillage Impacts On Soil Health And Soil Nitrogen In Indiana, Jennifer D. Woodyard

Open Access Theses

Cover crops, plants grown during the fallow period between cash crop growing seasons, have gained increasing amounts of attention throughout the agriculture industry in recent years. Many producers use them to reduce soil erosion, scavenge nutrients, and improve soil structure, water infiltration, and soil health, but questions still remain on maximizing cover crop benefits while simultaneously maintaining or improving cash crop production. This study measured cover crop and no-tillage effects on soil nitrogen and cash crop yield across multiple sites in Indiana beginning in fall 2015 and ending in fall 2017, typically in a corn (Zea mays L.)/soybean (Glycine max …

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Geology, U-Pb Geochronology, And Hf Isotope Geochemistry Across The Alaska Range Suture Zone (South-Central Alaska): Implications For Collisional Processes And Cordilleran Tectonics, Mariah C. Romero May 2018

Geology, U-Pb Geochronology, And Hf Isotope Geochemistry Across The Alaska Range Suture Zone (South-Central Alaska): Implications For Collisional Processes And Cordilleran Tectonics, Mariah C. Romero

Open Access Theses

The Alaska Range suture zone is defined by a transition from outboard oceanic terranes to inboard continental margin terranes; distinguishing south-central Alaska as a prime place to study the progressive development of a collisional tectonic setting. We present 3,206 U-Pb analyses and 406 Hf isotope compositions from detrital zircons obtained from the three main components of the collisional zone: the Ancestral North American continental margin, the oceanic Wrangellia terrane, and the sedimentary strata of the Jurassic-Cretaceous Kahiltna assemblage. U-Pb/Hf datasets from the Ancestral North American continental margin and oceanic Wrangellia terrane provide a provenance reference when comparing the Kahiltna assemblage …

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Cross-Linguistic Influence Of Loanwords On Japanese Particle Processing: Evidence From Japanese Language Learners, Ryosuke Yamamoto May 2018

Cross-Linguistic Influence Of Loanwords On Japanese Particle Processing: Evidence From Japanese Language Learners, Ryosuke Yamamoto

Open Access Theses

Studies have proposed that the spreading activation (SA) theory (Colins, & Loftus, 1975) can explain the nature of L1 and L2 predictive sentence processing (e.g., Kaan, 2014). Research on processing in L2 English has found that word information triggers learners’ semantically-driven predictive sentence processing (e.g., Hopp, 2015); however, to the best of my knowledge, few studies have been conducted in L2 Japanese. Additionally, what triggers L2 predictive sentence processing is yet to be fully discovered. Research has demonstrated that L1 English learners of Japanese as a foreign language (JFL) show cognate-like effects when English-based loanwords are used as primes in …

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Blokcar: Creating Interactive In-Car Entertainment System For Children, Hsin-Man Wu May 2018

Blokcar: Creating Interactive In-Car Entertainment System For Children, Hsin-Man Wu

Open Access Theses

The research proposes an in-car entertainment system for children to relieve their in-car boredom and further enhance the travel experience. While more and more attention has already been paid on human-car interaction, there is still very limited research considering the interaction between back seat passengers and the car. This project aims to explore the new research area and solve the problems for the children passengers. Based on the research (Price & Matthews, 2013; Wilfinger et al., 2011), many parents reported the quality time they spent with their children in the car was invaluable. Due to the limited space of a …

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Physiological And Molecular Response Of Soybean To Drought And Heat Stresses, Congshan Xu May 2018

Physiological And Molecular Response Of Soybean To Drought And Heat Stresses, Congshan Xu

Open Access Theses

Drought and heat are two of the major adverse environmental stresses for plants. The plant growth, productivity, morphology, physiology and biochemistry are found to be changed when the plants are grown at either drought or heat or combined stress conditions. Photosynthesis, stomata conductance, transpiration, water potential, and antioxidant systems were found to be involved in facilitating the stress responses. In addition, multiple molecular pathways, e.g., protective compound synthesis, protein and mRNA chaperones, cell membrane fluidity, plant hormone synthesis and transport, secondary metabolite synthesis, and flowering, have also been discovered to be involved in the response to these conditions. Soybean is …

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The Impacts Of Providing And Receiving Formative Peer Feedback On Secondary Students Achievement On A Graphic Design Project, Emily Yoshikawa May 2018

The Impacts Of Providing And Receiving Formative Peer Feedback On Secondary Students Achievement On A Graphic Design Project, Emily Yoshikawa

Open Access Theses

Formative assessment is a widely accepted practice in education today aimed towards high student achievement (Gielen & De Weaver, 2015). Despite its’ acceptance, there remains some confusion, as well as contradictory ideas, around the best practices of formative assessment and, explicitly, feedback through formative assessment (Shute, 2008). There is specifically a lack of clarity on the impact of individual elements of providing and/or receiving formative feedback on student achievement. Further, the influence of this feedback, if provided to/from peers in formative settings, is not fully understood (Liu & Carless, 2006). These ideas are important to understand so as to help …

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Growth, Physiological And Molecular Mechanisms Of Low Nitrogen Stress Tolerance In Perennial Ryegrass, Yanyu Yao May 2018

Growth, Physiological And Molecular Mechanisms Of Low Nitrogen Stress Tolerance In Perennial Ryegrass, Yanyu Yao

Open Access Theses

Perennial ryegrass is a widely used cool-season grass for forage and turfgrass in the temperate regions. Perennial ryegrass needs high fertility levels to maintain its turf quality and production. Nitrogen (N) is a major macronutrient for plant growth and development. The deficiency of N can cause chlorosis, loss of shoot density and decrease in growth. However, the overuse of N can cause pollution in atmosphere, water and soil. The objectives of this study were to: (i) investigate growth and physiological mechanisms of perennial ryegrass accessions exposed to low N stress; (ii) examine the effects of low N stress on antioxidant …

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Improving Irwls Algorithm For Glm With Intel Xeon Family, Zhenzhi Xu May 2018

Improving Irwls Algorithm For Glm With Intel Xeon Family, Zhenzhi Xu

Open Access Theses

This study investigates utilizing the characteristics of Intel Xeon to improve the performance of training generalized linear models. The classic approach to fnd the maximum likelihood estimation of linear model requires loading entire data into memory for computation which is infeasible when data size is bigger than memory size. With the approach analyzed by Zhang and Yang (2017), the process of model fitting will be achieved iteratively through iterating each row. However, one limitation of this approach could be the iterative manner will impact performance when implementing it on Intel Xeon processor which delivers parallelism and vectorization. The study will …

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Approximating Signed Distance Field To A Mesh By Artificial Neural Networks, Zhe Zeng May 2018

Approximating Signed Distance Field To A Mesh By Artificial Neural Networks, Zhe Zeng

Open Access Theses

Previous research has resulted in many representations of surfaces for rendering. However, for some approaches, an accurate representation comes at the expense of large data storage. Considering that Artifcial Neural Networks (ANNs) have been shown to achieve good performance in approximating non-linear functions in recent years, the potential to apply them to the problem of surface representation needs to be investigated. The goal in this research is to exploring how ANNs can effciently learn the Signed Distance Field (SDF) representation of shapes. Specifcally, we investigate how well different architectures of ANNs can learn 2D SDFs, 3D SDFs, and SDFs approximating …

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Degradation Of Trihalomethanes And Choramines By Uv And Vuv Irradiation, Kehui Zhang May 2018

Degradation Of Trihalomethanes And Choramines By Uv And Vuv Irradiation, Kehui Zhang

Open Access Theses

Disinfection byproducts (DBPs) generated from the chlorination of natural organic matter (NOM) represent a source of concern related to drinking water quality. Vacuum-ultraviolet (VUV <200 >nm), irradiation can be an efficient advanced oxidation process (AOP), has been documented to inactivate pathogens as well as remove micropollutants in drinking water. To compare the effects of VUV and UVC irradiation, four trihalomethanes (THMs) and three chloramines, chloroform (CHCl3), dichlorobromomethane (CHBrCl2), dibromochloromethane (CHBr2Cl), bromoform (CHBr3), monochloramine (NH2Cl), dichloramine (NHCl2) and trichloramine (NCl3), were prepared and analyzed for their degradation reaction rate constant under UVC, VUV/UVC, UVC/Cl2, VUV/UVC/Cl2 processes. A mini-fluidic VUV/UVC photoreaction system …

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Understanding The Effect Of Extrusion Conditions On Melt Viscosity To Aid In Modeling Of A Single Screw Extruder With Internal Restrictions For Scale-Up Purposes., Troy Tonner May 2018

Understanding The Effect Of Extrusion Conditions On Melt Viscosity To Aid In Modeling Of A Single Screw Extruder With Internal Restrictions For Scale-Up Purposes., Troy Tonner

Open Access Theses

A single screw extruder with inner restrictions that is self-heated by friction and viscous dissipation was investigated. The effect of the processing parameters: feed moisture, screw speed, and feed rate on the melt viscosity and die temperature rise were researched using a dual orifice die. The melt viscosity was also measured using an offline capillary rheometer. The offline data was compared to and used to predict the inline viscosity of the melt. Various methods such as multi-linear regression and superpositioning were used to model viscosity as a function of the processing parameters. Next, the current analytical model was evaluated using …

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Estimating Likelihood Of Severe Damage Due To Earthquakes In Reinforced Concrete Frame Buildings In Afghanistan, Sekandar Zadran May 2018

Estimating Likelihood Of Severe Damage Due To Earthquakes In Reinforced Concrete Frame Buildings In Afghanistan, Sekandar Zadran

Open Access Theses

Afghanistan has a history of devastating earthquakes claiming many lives and causing extensive damage. It is important to identify buildings vulnerable to ground shaking in an efficient manner and to upgrade or rebuild them to avoid losses during earthquakes in the future. In June 2017, 51 reinforced concrete (RC) school buildings with solid masonry infill walls and no structural walls were surveyed in Kabul, Afghanistan. Besides photographic documentation and location information, building dimensions including column dimensions and masonry wall dimensions, as well as wall orientation information, and number of stories above ground were recorded. To rank these buildings in vulnerability …

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Visualizing The Motion Flow Of Crowds, Zheng Zhao May 2018

Visualizing The Motion Flow Of Crowds, Zheng Zhao

Open Access Theses

In modern cities, massive population causes problems, like congestion, accident, violence and crime everywhere. Video surveillance system such as closed-circuit television cameras is widely used by security guards to monitor human behaviors and activities to manage, direct, or protect people. With the quantity and prolonged duration of the recorded videos, it requires a huge amount of human resources to examine these video recordings and keep track of activities and events. In recent years, new techniques in computer vision field reduce the barrier of entry, allowing developers to experiment more with intelligent surveillance video system. Different from previous research, this dissertation …

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Selecting The Minimum Battery Range For Battery Electric Vehicles With Public Recharging, Yue Zhou May 2018

Selecting The Minimum Battery Range For Battery Electric Vehicles With Public Recharging, Yue Zhou

Open Access Theses

The choice of battery range (all-electric driving range) for the battery electric vehicles (BEVs) is an important issue for both the BEV adopters and the BEV makers. This study proposes a Mix-integer Nonlinear Programming (MINLP) model to identify the minimum BEV battery range that can satisfy given travel demands for a driver or vehicle owner, considering the opportunities to charge at existing public charging stations and the uncertainties in charging decision making. I conducted a Stated Preference survey to study the charging decision making under the key factors of dwell time, remaining battery energy, distance of the upcoming trip, charging …

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Distribution And Spread Of An Invasive Shrub (Pyrus Calleryana Decne) Across Environmental Gradients In Southern Indiana, Kalli Dunn May 2018

Distribution And Spread Of An Invasive Shrub (Pyrus Calleryana Decne) Across Environmental Gradients In Southern Indiana, Kalli Dunn

Open Access Theses

Invasive species represent one of the greatest challenges to ecological management today. With new species introductions occurring every year, understanding the impacts, mechanisms of spread, and characteristics of invaded habitats is vital in developing appropriate control methods. One newly escaped invasive species, Pyrus calleryana, is rapidly expanding its invasive range and potentially altering forest structure and composition in southern Indiana. This research investigated characteristics of invaded environments and patterns of spread in P. calleryana. I found an association between P. calleryana and areas with high levels of light and high stocking of shade intolerant species. Data further revealed an association …

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Hybrid Energy Storage Systems For Uav Applications, John J. Ganser May 2018

Hybrid Energy Storage Systems For Uav Applications, John J. Ganser

Open Access Theses

Energy storage constraints limit the range and endurance of electric based unmanned aerial vehicles (UAVs). Solving the energy storage problem allows the adoption of UAVs on a much wider scale. A solution to the problem would ideally retain the significant performance and efficiency benefits of the electric based propulsion system. The contents of this study focused on solving the energy storage problem through research, experiment, and simulation based testing of the application of hybrid energy storage systems (HESS) to existing UAV designs. A review of literature was done exploring existing and future applications of electric based aircraft propulsion systems. Research …

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A 360 Vr And Wi-Fi Tracking Based Autonomous Telepresence Robot For Virtual Tour, Yeonju Oh May 2018

A 360 Vr And Wi-Fi Tracking Based Autonomous Telepresence Robot For Virtual Tour, Yeonju Oh

Open Access Theses

This study proposes a novel mobile robot teleoperation interface that demonstrates the applicability of a robot-aided remote telepresence system with a virtual reality (VR) device to a virtual tour scenario. To improve realism and provide an intuitive replica of the remote environment for the user interface, the implemented system automatically moves a mobile robot (viewpoint) while displaying a 360-degree live video streamed from the robot to a VR device (Oculus Rift). Upon the user choosing a destination location from a given set of options, the robot generates a route based on a shortest path graph and travels along that the …

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A Genetic Approach To Pinning Down The Wanderer: Mapping Vagal Afferent Innervation Of The Mouse Intestinal Mucosa, Hannah Kathleen Serlin May 2018

A Genetic Approach To Pinning Down The Wanderer: Mapping Vagal Afferent Innervation Of The Mouse Intestinal Mucosa, Hannah Kathleen Serlin

Open Access Theses

Vagal afferents that supply the small intestine mucosa play a key role in signaling satiation and regulating digestion. Little is known about the morphology or distribution of this innervation. A major obstacle has been the ability to selectively label a large proportion of vagal mucosal afferents independent of other extrinsic and intrinsic gastrointestinal tract innervation. A recent breakthrough revealed that Nav1.8Cre-Tomato control (CON) mice express Tomato protein in ~80% nodose and dorsal root ganglion (DRG) cells and in mucosal afferents throughout the intestines (Gautron, 519:3085, 2011). Subdiaphragmatic vagotomy in CON mice (VAGX) resulted in a complete loss of this mucosal …

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System Of Systems Analyses Using Model Based Systems Engineering, Steven A. Zusack May 2018

System Of Systems Analyses Using Model Based Systems Engineering, Steven A. Zusack

Open Access Theses

This study aims to address two major challenges faced at early stages of development, commonly called Pre-Phase A, for complex space-based mission architectures. The first challenge is a lack of detailed system information when an assessment of competing architecture concepts is needed. To counter this challenge, the Systems Operational Dependency Analysis and architecture-level parametric cost methods are used. These methods produce meaningful evaluation metrics for direct comparison of architecture concepts by utilizing both limited, high-level information as well as any detailed, low-level information that may be available. The second challenge is the ability to quickly and efficiently alter, add, or …

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The Effects Of Prescribed Fire On Overstory Tree Quality And Stand Volume In Eastern Deciduous Forests, Shannon P. Stanis May 2018

The Effects Of Prescribed Fire On Overstory Tree Quality And Stand Volume In Eastern Deciduous Forests, Shannon P. Stanis

Open Access Theses

The use of prescribed fire for ecosystem restoration presents numerous questions for natural resource managers. One of these questions, the impact of prescribed fire on overstory tree quality and stand volume, is explored here prospectively and retrospectively. A long-term study is being installed in 20 oak-dominated stands across central and southern Indiana to monitor effects of repeated prescribed fire on overstory tree quality. Prior to the initial prescribed fire, 20 average quality and 10 highest quality trees in each stand were measured for grade and defects below breast height. Each prescribed burn is monitored with thermal paints and thermocouples at …

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Synthesis Of Ethylene Antagonists And An Anticancer Dupa Conjugate, Bin Zhang May 2018

Synthesis Of Ethylene Antagonists And An Anticancer Dupa Conjugate, Bin Zhang

Open Access Theses

Ethylene is used by plants as a hormone to control many physiological processes throughout the lifetime of a plant, including seed germination, growth, formation of the apical hook, organ senescence, fruit ripening, abscission, gravitropism and responses to various stresses.1 1methylcyclopropene is the most widely used ethylene antagonist on the market currently. Studies show that 1-alkylcyclopropene compounds react with a Cu(I) ion in the active site of ethylene receptor 1 (ETR1) forming carbenoids and deactivating ETR1.1’2,3 There is still a great demand for novel ethylene antagonists because 1-MCP has some drawbacks such as high volatility, low solubility in water, and high …

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A Study Of Student Comfort And Satisfaction Within Green Residence Halls, Wesley Matthew Young May 2018

A Study Of Student Comfort And Satisfaction Within Green Residence Halls, Wesley Matthew Young

Open Access Theses

This research contributes to a better understanding of whether green university residential halls benefit students by creating better occupant comfort and satisfaction. Residential halls were considered green by this thesis if they achieved LEED certification. This study addresses Indoor Environmental Quality (IEQ) in relation to comfort and satisfaction among the college students living in residential halls. The present study surveyed Purdue University students living in a conventional residence hall (First Street Towers) compared with students living in a LEED Gold certified residence hall (Third Street Suites) regarding the comfort and satisfaction provided by their residence halls. A Building Use Studies …

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A 3d-Cell Based Assay To Detect Shiga-Like Toxin Producing Escherichia Coli, Celina To May 2018

A 3d-Cell Based Assay To Detect Shiga-Like Toxin Producing Escherichia Coli, Celina To

Open Access Theses

Shiga-like toxin producing Escherichia coli (STEC), a foodborne pathogen, poses a serious public health risk. Rapid detection of STEC in the food supply remains to be a challenge because current detection methods lack the ability to differentiate viable and non-viable STEC or active and inactive Shiga-like toxins (Stx) in less than 24 h. Here, our goal was to develop a mammalian cell-based assay (CARD) for rapid high-throughput detection of Shiga-toxin producing Escherichia coli using Vero (monkey kidney epithelial cells) or THP-1 (human monocyte cell) cell lines. Initially, optimal mammalian cell concentration needed to show a maximum cytotoxicity towards a membrane …

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Consensus And Platooning In Multiagent Networks, Jiazhi Song May 2018

Consensus And Platooning In Multiagent Networks, Jiazhi Song

Open Access Theses

First, a distributed algorithm to accelerate the convergence of a class of linear time-invariant consensus-based distributed algorithms is proposed. Then, it is proven that, given a convergent distributed algorithm, the acceleration algorithm can ensure convergence and consensus. Also, the parameter that can ensure the largest possible convergence speed was determined. Furthermore, it is shown that some constraints on the equilibrium state of the original algorithms also apply to the equilibrium state of the acceleration algorithm. Finally, some examples are presented to validate the effectiveness of the acceleration algorithm. A method that allows obtaining convergence value within a finite amount of …

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Enrichment Of Turbulence Field Using Wavelets, Yifan Du May 2018

Enrichment Of Turbulence Field Using Wavelets, Yifan Du

Open Access Theses

This thesis is composed of two parts. The first part presents a new turbulence generation method based on stochastic wavelets and tests various properties of the generated turbulence field in both the homogeneous and inhomogeneous cases. Numerical results indicate that turbulence fields can be generated with much smaller bases in comparison to synthetic Fourier methods while maintaining comparable accuracy. Adaptive generation of inhomogeneous turbulence is achieved by a scale reduction algorithm, which greatly reduces the computational cost and practically introduces no error. The generating formula proposed in this research could be adjusted to generate fully inhomogeneous and anisotropic turbulence with …

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Evidentiary Reasoning: An Examination Of Elementary And Middle School Students' Knowledge Of Scientific Evidence In Biology, Jamison Wills May 2018

Evidentiary Reasoning: An Examination Of Elementary And Middle School Students' Knowledge Of Scientific Evidence In Biology, Jamison Wills

Open Access Dissertations

This project examines upper elementary and middle school students’ knowledge of scientific evidence. Informed by literature in cognitive development, learning sciences, and science education, this proposal argues that science educators have typically treated evidence as a simple and unitary construct that is disconnected from other phases of scientific activity. Evidence in the philosophy and history of science, on the other hand, is multifaceted, sophisticated, and involves the coordination of disciplinary knowledge and methodological practices. Based on a conceptual analysis of evidence in this literature, I developed a framework of evidential dimensions that important to scientific reasoning. Two fifth and two …

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Particle Streak Velocimetry: A Diagnostic For High Speed Flows, Jared D. Willits May 2018

Particle Streak Velocimetry: A Diagnostic For High Speed Flows, Jared D. Willits

Open Access Dissertations

This work describes the development and implementation of a novel velocimetry technique to probe the exhaust flow of a cold gas thruster. The diagnostic combines the advantages of standard particle velocimetry techniques and the ultra-fast imaging capabilities of a streak camera to probe high speed flows near continuously with improved spatial and velocity resolution compared to Particle Image Velocimetry. This “Particle Streak Velocimetry” technique tracks illuminated seed particles at up to 4.2 GHz allowing time-resolved measurement of one-dimensional flows exceeding 2000 m/s as are found in rocket nozzles and many other applications (US Provisional Patent filed 05/19/16). Single frame images …

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