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2017

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Evaluation Of Alkalis, Buffers, And Complementary Fiber Feeds To Increase Digestibility And Performance In Feedlot Steers Fed Corn Stover, Nicholas Allan Lancaster Dec 2017

Evaluation Of Alkalis, Buffers, And Complementary Fiber Feeds To Increase Digestibility And Performance In Feedlot Steers Fed Corn Stover, Nicholas Allan Lancaster

Open Access Theses

The use of dried distillers grains with solubles (DDGS) has been shown to limit fiber digestibility due to the inherent acidity of the feedstuff. Three studies were conducted to evaluate the effect of alkalis, buffers and complimentary fiber feeds on ruminal pH, fiber digestibility, and animal performance. The first study was conducted to determine the effectiveness of calcium hydroxide (StoverCal; Ca(OH)2) and/or roughage on diet digestibility, performance and carcass characteristics of steers fed 60% DDGS. The addition of StoverCal to low corn silage diets, or the addition of corn silage or corn stover to a 60% DDGS ration did not …

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A Systematic Literature Review To Identify Best Practices For Communication In Virtual Teams, Arielle Mabon Dec 2017

A Systematic Literature Review To Identify Best Practices For Communication In Virtual Teams, Arielle Mabon

Open Access Theses

Virtual teams are necessary for organizations to remain competitive in today’s global society, but the complexities of virtual team environments impart strain on virtual teams to perform key team activities. Although virtual teams are expected to deliver complex projects, training for communicating in virtual teams is often overlooked. This thesis was conducted using a systematic literature review of peer-reviewed articles from 2012-2017 to identify elements of communication that contributed to virtual team effectiveness and communication best practices that may be perceived as prescriptive content for virtual team communication training. The results of this study suggest that virtual team communication training …

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An Examination Of The Relationship Between Fitts' Law And Schmidt's Law, Jonathan Mckeeman Dec 2017

An Examination Of The Relationship Between Fitts' Law And Schmidt's Law, Jonathan Mckeeman

Open Access Theses

There are two prominent speed accuracy tradeoff relationships; Fitts’ Law and Schmidt’s Law. The Fitts tasks are considered to be spatially constrained, whereas the Schmidt tasks are temporally constrained. In this experiment the relationship between these two speed accuracy tradeoffs was examined. Previous studies have allowed for the hypothesis that these two laws may be related or share similar control processes. Through analysis of the previous literature on the subject I hypothesized that the two speed accuracy tradeoffs are unrelated and do not share a common control process. To test this hypothesis, participants performed both speed accuracy tradeoff tasks under …

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Cosmogenic Be-10 And Cl-36 In Magnetite, Angus Moore Dec 2017

Cosmogenic Be-10 And Cl-36 In Magnetite, Angus Moore

Open Access Theses

Cosmogenic nuclides are widely used to assess catchment-averaged denudation rates, although the method has been largely limited to the nuclide 10Be in the target mineral quartz. This is because (a) quartz is resistant to weathering, (b) the production rate of 10Be in quartz has been extensively studied and is well-constrained, and (c) quartz may be reliably separated from other minerals and cleaned of meteoric 10Be. Denudation rates have remained difficult to measure in volcanic landscapes due to a lack of quartz and the rapid weathering of olivine and other alternative target minerals. This creates an interest in developing new target …

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Orbit Maintenance Strategies For Sun-Earth/Moon Libration Point Missions: Parameter Selection For Target Point And Cauchy-Green Tensor Approaches, Vivek Muralidharan Dec 2017

Orbit Maintenance Strategies For Sun-Earth/Moon Libration Point Missions: Parameter Selection For Target Point And Cauchy-Green Tensor Approaches, Vivek Muralidharan

Open Access Theses

The libration point orbits in the Sun-Earth/Moon system are formed by concurrent gravitational influences by various celestial bodies, originating in a nonlinear dynamical regime. Coupled with the unstable nature of the orbit, the impact of any perturbations are expected to increase rapidly. The feasibility of a flow-based, Cauchy-Green tensor control strategy for station-keeping is examined. An orbit consistent with the mission objectives is selected for examination. The station-keeping process is stochastic, thus Gaussian random errors are introduced for simulation. The evolution of a velocity perturbation over time is monitored, beyond which the attainable state in the accessible region nearest to …

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Experimental Investigation Of Inlet Distortion In A Multistage Axial Compressor, Razvan Rusu Dec 2017

Experimental Investigation Of Inlet Distortion In A Multistage Axial Compressor, Razvan Rusu

Open Access Theses

The primary objective of this research is to present results and methodologies used to study total pressure inlet distortion in a multi-stage axial compressor environment. The study was performed at the Purdue 3-Stage Axial Compressor Facility (P3S) which models the final three stages of a production turbofan engine’s high-pressure compressor (HPC). The goal of this study was twofold; first, to design, implement, and validate a circumferentially traversable total pressure inlet distortion generation system, and second, to demonstrate data acquisition methods to characterize the inter-stage total pressure flow fields to study the propagation and attenuation of a one-per-rev total pressure distortion. …

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Atmospheric Rural Community And Tourists' Experience -- China's Rural Tourism And Seniors' Quality Of Life, Jieyu Shi Dec 2017

Atmospheric Rural Community And Tourists' Experience -- China's Rural Tourism And Seniors' Quality Of Life, Jieyu Shi

Open Access Theses

The increasing percentage of aged populations in many parts of the world is an issue of global attention and significance. China is no exception and faced with a pressing challenge to find solutions for improving seniors’ quality of life. Extending the extant knowledge on the relationship between tourism and health, the current study posits that rural tourism, as a growing and popular form of leisure in China, can enhance the quality of life for both senior tourists and senior locals and proposes the concept of atmospheric community for rural tourism. This study develops the concept by investigating the elements of …

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Responses Of Soil Greenhouse Gas Fluxes To Simulated Nitrogen Deposition And Rainfall Variability In A Tallgrass Prairie, Megan Scott Dec 2017

Responses Of Soil Greenhouse Gas Fluxes To Simulated Nitrogen Deposition And Rainfall Variability In A Tallgrass Prairie, Megan Scott

Open Access Theses

Climate change has altered precipitation regimes in many regions of the world. In the Midwestern United States, the intensity of precipitation events had increased, and the periods of drought between them have lengthened. Since the Industrial Revolution, nitrogen (N) deposition has increased and may further increase in response to growth in fossil fuel consumption and fertilizer use. Continuing changes in precipitation variability and N inputs will impact carbon (C) and N-cycling processes and atmospheric levels of greenhouse gases (GHG). Controlled by a variety of processes, soil GHG (CO2, N2O, and CH4) fluxes play a large role in determining atmospheric GHG …

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Effects Of Dietary Pectin And Threonine Concentrations On The Growth Performance, Digestibility And Intestinal Morphology Of Broiler Chickens, Yu Shi Dec 2017

Effects Of Dietary Pectin And Threonine Concentrations On The Growth Performance, Digestibility And Intestinal Morphology Of Broiler Chickens, Yu Shi

Open Access Theses

The experiment was conducted to determine the effect of dietary threonine (Thr) concentration and dietary pectin and the interaction effects of dietary pectin and dietary Thr concentrations on growth performance, nutrient digestibility and intestinal morphology of broiler chickens from d 7 to 21 posthatch. Ten diets with five levels of dietary Thr concentration of 5.7, 7.6, 9.4, 11.3, 13.2 g/kg, representing 60, 80, 100, 120, 140%, respectively, of the Thr requirement suggested by Ross Nutrition Supplement (2009), and two levels of dietary pectin (0 and 7%) were fed to broiler chickens from d 7 to d 21 posthatch in a …

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Quantifying The Regional Extent And Magnitude Of Interbasin Groundwater Flow And Its Role In Climatic Perturbations In Northern New Mexico, Usa, Noah Stewart-Maddox Dec 2017

Quantifying The Regional Extent And Magnitude Of Interbasin Groundwater Flow And Its Role In Climatic Perturbations In Northern New Mexico, Usa, Noah Stewart-Maddox

Open Access Theses

Interbasin groundwater flow (IGF) occurs when water that is recharged in one watershed or basin discharges into an adjacent watershed or basin. This contributes additional water and solute mass to the receiving watershed complicating water and solute mass-balance estimates. Additionally, IGF can alter the response time of a watershed in two primary ways, where response time is defined as the amount of time it takes for a watershed to respond to some perturbation that causes a change in recharge. First, changes that occur outside the watershed in the contributing watershed can impact process behavior in the receiving watershed. Secondly, the …

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Sensor Fusion To Detect Scale And Direction Of Gravity In Monocular Slam Systems, Seth C. Tucker Dec 2017

Sensor Fusion To Detect Scale And Direction Of Gravity In Monocular Slam Systems, Seth C. Tucker

Open Access Theses

Monocular simultaneous localization and mapping (SLAM) is an important technique that enables very inexpensive environment mapping and pose estimation in small systems such as smart phones and unmanned aerial vehicles. However, the information generated by monocular SLAM is in an arbitrary and unobservable scale, leading to drift and making it difficult to use with other sources of odometry for control or navigation. To correct this, the odometry needs to be aligned with metric scale odometry from another device, or else scale must be recovered from known features in the environment. Typically known environmental features are not available, and for systems …

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Digimesh Reliability In High Speed Vehicular Applications, Bogdan A. Visan Dec 2017

Digimesh Reliability In High Speed Vehicular Applications, Bogdan A. Visan

Open Access Theses

In a fast-paced technological society, advances in wireless networking show potential to save lives. Communication is key to notifying Emergency Medical Services of a potentially deadly accident in near real-time. This paper will discuss the use of low powered wireless devices transmitting life-saving information autonomously. Current and planned technologies used in vehicles are built-in, costly, and vulnerable to physical destruction. Using an independent system can offer both old and new vehicles primary and secondary communication. The results from this research study show that vehicles can use DigiMesh as a viable solution, although relative velocity affects its performance.

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Leveraging Uas For 3d Orthomosaid Aircraft Images To Support Maintenance Activities, William Weldon Dec 2017

Leveraging Uas For 3d Orthomosaid Aircraft Images To Support Maintenance Activities, William Weldon

Open Access Theses

As high ultra-high resolution aerial imaging becomes inexpensive and easily acquired through unmanned aerial systems, UAS, inspection industries are presented with the opportunity to reduce cost without reducing inspection quality. UAS technology allows for images to be taken at a relatively low cost with accuracy equivalent to laser scanning systems. A UAS equipped with a camera can be used to create a three dimensional orthomosaic model of an aircraft. This model has the potential to: increase the speed of visual inspections, increase the safety of visual inspections, improve maintenance training practices, and allow for aircraft condition tracking. The creation of …

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Unsteady Aerodynamics And Blade-Row Interactions In The Embedded Stage Of An Axial Compressor, Douglas Ryan Matthews Dec 2017

Unsteady Aerodynamics And Blade-Row Interactions In The Embedded Stage Of An Axial Compressor, Douglas Ryan Matthews

Open Access Theses

In a mature engineering field like compressor aerodynamics, the most accessible advances in machine technology, translating to performance and efficiency, have been discovered and have found industry design applications. As the community continues to make progress, increasingly challenging aspects of the involved physics must be exploited. Modern turbomachinery operates with larger bypass ratios, smaller cores, and lighter, thinner, and more flexible materials resulting in the maintenance of higher operating pressures and temperatures. As the performance and efficiency of these machines continues to climb, the same technological advances reinforce challenges like forced-response vibration, high-cycle fatigue of engine components, and large relative …

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Low-Cost Printer For Prototyping Circuits On Flexible Substrates Using Conductive Inks, Taylor J. Zigon Dec 2017

Low-Cost Printer For Prototyping Circuits On Flexible Substrates Using Conductive Inks, Taylor J. Zigon

Open Access Theses

The purpose of this project was to design a low-cost printer for prototyping circuits on flexible substrates using conductive and dielectric inks. Computer numeric controlled (CNC) machines are capable of conducting precise movements quickly and are commonly used for additive and subtractive manufacturing. A CNC machine is developed to add conductive ink to substrates utilizing an extrusion-based printing method. Usage of this extrusion method has the possibility of printing flexible electronics and being used for rapid electronic prototyping. This research will further expand on the capabilities of conductive inks and the substrates in which they can be applied.

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Optimized Command Shaping With Constrained Peak Input Acceleration For Minimizing Residual Vibration, Bowen Wu Dec 2017

Optimized Command Shaping With Constrained Peak Input Acceleration For Minimizing Residual Vibration, Bowen Wu

Open Access Theses

The fast point-to-point motion of a robotic system can be greatly affected by its joint flexibilities, which introduce vibrations during and after motion. While numerous techniques were developed to minimize the residual vibration of the flexible robotic system, this work studies the command shaping method. This method constructs an input profile that aims to reduce excitation energy around the natural frequencies to minimize residual vibration. This work modifies the command shaping method by applying a numerical optimization technique with a constraint on peak input acceleration. A framework has been constructed for the combination of these two modifications, which proved their …

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Novel Polymer/Bioactive Glass Composites For Bone Regenerative Engineering, Jessica Zuponcic Dec 2017

Novel Polymer/Bioactive Glass Composites For Bone Regenerative Engineering, Jessica Zuponcic

Open Access Theses

Bone-grafting procedures are necessary when injury to the bone, due to trauma or disease, surpasses the bone’s ability to auto-repair. These injuries are known as critical-sized defects. Using graft material from the patient’s own body, autografting, risks donor site morbidity and is size-limited [1, 2]. Using graft material from a donor or cadaver, allografting, carries some risk of disease transmission and availability is insufficient to meet demand [1]. These challenges have necessitated the development and use of bone graft substitutes which, ideally, can match the structural and mechanical properties of native bone and promote osteogenic differentiation of host cells – …

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Algorithms For Efficient Fail Data Collection For Defect Diagnosis, Shraddha Bodhe Dec 2017

Algorithms For Efficient Fail Data Collection For Defect Diagnosis, Shraddha Bodhe

Open Access Dissertations

A tester collects failure information for faulty circuits in order to perform defect diagnosis and derive information about the defects that is important for yield improvement. The increase in the complexity of the semiconductor manufacturing process and the higher number of defects due to scaling have caused an increase in the volume of fail data generated. However, with limited tester memory, fail data collection may terminate without acquiring data that is important for diagnosis. Additionally, a large amount of tester time is spent in data collection, increasing the overall test cost. This thesis presents several algorithms for efficient fail data …

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Effects Of Calcium Hydroxide Treated Corn Stover Inclusion As A Partial Forage Replacement In Diets For Lactating Dairy Cows, Brittany Casperson Dec 2017

Effects Of Calcium Hydroxide Treated Corn Stover Inclusion As A Partial Forage Replacement In Diets For Lactating Dairy Cows, Brittany Casperson

Open Access Dissertations

There is a large quantity of harvestable corn stover available in the United States. Due to the high maturity at harvest and subsequent low digestibility, the use of corn stover as a livestock feedstuff is limited. Several treatment and processing strategies have been explored in order to increase yield of fermentable sugars and lessen the limitation of corn stover as a feedstuff. Alkaline pretreatment has been applied to enhance the digestibility of low quality feeds, improve the feeding value, and permit use in livestock rations. The central hypothesis of this dissertation is that calcium hydroxide treatment would improve the feeding …

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Improving The Policy Specification For Practical Access Control Systems, Haining Chen Dec 2017

Improving The Policy Specification For Practical Access Control Systems, Haining Chen

Open Access Dissertations

Access control systems play a crucial role in protecting the security of information systems by ensuring that only authorized users are granted access to sensitive resources, and the protection is only as good as the access control policies. For enabling a security administrator to express her desired policy conveniently, it is paramount that a policy specification is expressive, comprehensible, and free of inconsistencies. In this dissertation, we study the policy specifications for three practical access control systems (i.e., obligation systems, firewalls, and Security-Enhanced Linux in Android) and improve their expressiveness, comprehensibility, and consistency. First, we improve the expressiveness of obligation …

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Border Relations: A Bioarchaeological Lnvestigation Of The Xiongnu Polity, Jeremy J. Beach Dec 2017

Border Relations: A Bioarchaeological Lnvestigation Of The Xiongnu Polity, Jeremy J. Beach

Open Access Dissertations

The Xiongnu were the first mobile pastoralist steppe polity to rise up from the Mongolian Steppe. Previous scholarship attributed the emergence of the Xiongnu to their peripheral location and interactions with sedentary China. It was argued that a polity the size of the Xiongnu could not be sustained on a pastoral economy, therefore they turned their attention to interactions with China to fuel their economic and political growth outside of the steppe. This line of thought has come to be known as Dependency Theory and food was at the center of this dependency argument. The expansion of a pastoral economy …

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Developing And Measuring Effectiveness Of A New Evidence-Based Grain Storage And Handling Safety Curriculum Targeting Young And Beginning Workers, Yuan-Hsin Cheng Dec 2017

Developing And Measuring Effectiveness Of A New Evidence-Based Grain Storage And Handling Safety Curriculum Targeting Young And Beginning Workers, Yuan-Hsin Cheng

Open Access Dissertations

Research was conducted on the development, testing, and implementation of an original, evidence-based curriculum (Against the Grain) designed to reduce the frequency and severity of the most frequent types of injuries and fatalities involving young and beginning workers, ages 14-20, at grain storage and handling operations. This population has historically accounted for approximately 24% of documented entrapments, engulfments, asphyxiations, entanglements, falls, and electrocutions associated with grain handling and storage. This includes incidents during both workrelated and non-work or recreational activities. Curriculum contents were based upon data summarized from Purdue’s Agricultural Confined Spaces Incident Database (PACSID), review of relevant injury prevention …

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Analysis Of Data Of Different Spatial Support: A Multivariate Process Approach, Kelly-Ann N. Dixon Hamil Dec 2017

Analysis Of Data Of Different Spatial Support: A Multivariate Process Approach, Kelly-Ann N. Dixon Hamil

Open Access Dissertations

Inherent to a spatial variable is the unit of support at which it is measured. In many studies, variables are observed at different support. For example, disease rates might be measured at an aggregated level while temperature is usually measured at specific points. It is still an interesting problem to study the relationship of variables having different support. However, it may be a different problem to statistically model the relationship of variables of different support, particularly when the supports do not have a hierarchical structure. Currently, cokriging, the use of one or more spatial variables to predict another variable, is …

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A Collaborative Monocular Visual Simultaneous Localization And Mapping Solution To Generate A Semi-Dense 3d Map., Ruwan Janapriya Egodagamage Dec 2017

A Collaborative Monocular Visual Simultaneous Localization And Mapping Solution To Generate A Semi-Dense 3d Map., Ruwan Janapriya Egodagamage

Open Access Dissertations

The utilization and generation of indoor maps are critical in accurate indoor tracking. Simultaneous Localization and Mapping (SLAM) is one of the main techniques used for such map generation. In SLAM, an agent generates a map of an unknown environment while approximating its own location in it. The prevalence and afford-ability of cameras encourage the use of Monocular Visual SLAM, where a camera is the only sensing device for the SLAM process. In modern applications, multiple mobile agents may be involved in the generation of indoor maps, thus requiring a distributed computational framework. Each agent generates its own local map, …

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Learning Electron Transport Chain Process In Photosynthesis Using Video And Serious Game, Cecilia Espinoza Morales Dec 2017

Learning Electron Transport Chain Process In Photosynthesis Using Video And Serious Game, Cecilia Espinoza Morales

Open Access Dissertations

This research investigates students' learning about the electron transport chain (ETC) process in photosynthesis by watching a video followed by playing a serious board game-Electron Chute- that models the ETC process. To accomplish this goal, several learning outcomes regarding the misconceptions students' hold about photosynthesis and the ETC process in photosynthesis were defined. Middle school students need opportunities to develop cohesive models that explain the mechanistic processes of biological systems to support their learning. A six-week curriculum on photosynthesis included a one day learning activity using an ETC video and the Electron Chute game to model the ETC process. The …

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Effects Of Acute Aerobic Exercise On Whole Genome Nucleosome Maps, Transcriptomics And Acylcamitine Metabolomics In Skeletal Muscle Of Lean Vs Overweight/Obese Men, Prasad P. Devarshi Dec 2017

Effects Of Acute Aerobic Exercise On Whole Genome Nucleosome Maps, Transcriptomics And Acylcamitine Metabolomics In Skeletal Muscle Of Lean Vs Overweight/Obese Men, Prasad P. Devarshi

Open Access Dissertations

Skeletal muscle mitochondrial dysfunction, evidenced by incomplete beta oxidation and accumulation of fatty acid intermediates in the form of long and medium chain acylcarnitines, may contribute to ectopic lipid deposition and insulin resistance during high fat diet (HFD)-induced obesity. Anterograde and retrograde communication play a role in nucleo-mitochondrial crosstalk that determines skeletal muscle mitochondrial adaptations, specifically alterations in mitochondrial number and function in relation to obesity and insulin resistance. High fat diet (HFD) feeding affects the expression of nuclear-encoded mitochondrial genes (NEMGs) nuclear receptor factor 1 (NRF-1), 2 (NRF-2) and peroxisome proliferator receptor gamma coactivator 1 alpha (PGC-1α) thereby, playing …

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Materials-Genome-Based Multiscale Modeling Of Ceramics And Laser-Assisted Machining, Xiangyang Dong Dec 2017

Materials-Genome-Based Multiscale Modeling Of Ceramics And Laser-Assisted Machining, Xiangyang Dong

Open Access Dissertations

This study is concerned with developing multiscale models to predict material properties and simulate laser-assisted machining of ceramics. The microstructure and composition of ceramics and computational costs are taken into consideration in the development of multiscale models. These models can predict both mechanical and thermal properties, which can further assist in selecting machining parameters for laser-assisted machining of ceramics. Quantum level, atomistic level, micro and macro scales are bridged in the multiscale modeling of ceramics. Interatomic potentials are derived by ab initio methods to achieve more accurate calculations in molecular dynamics (MD) simulations. MD calculations are carried out to predict …

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A New Method For Determining Hamaker Constants Of Solids Based On The Dynamic Approach Behavior Of An Atomic Force Microscope, Sean G. Fronczak Dec 2017

A New Method For Determining Hamaker Constants Of Solids Based On The Dynamic Approach Behavior Of An Atomic Force Microscope, Sean G. Fronczak

Open Access Dissertations

The Hamaker constant, A, is a very important parameter used to quantify the strength of the van der Waals (vdW) attractive interaction among particles and between particles and surfaces. Consequently, an accurate measurement of A is of fundamental importance to a wide range of research and manufacturing fields. Therefore, this dissertation primarily focuses on the development and application of a new method to determine Hamaker constants of solid materials using an atomic force microscope (AFM). While the direct contact or pull-off method is typically employed during an AFM force measurement, this contact-technique is highly dependent upon material properties that are …

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The Effects Of Carbon Dioxide Addition On Turbulent Premixed Combustion, Dong Han Dec 2017

The Effects Of Carbon Dioxide Addition On Turbulent Premixed Combustion, Dong Han

Open Access Dissertations

Turbulent premixed combustion plays an important role in the development of gas turbine systems. Continuous work has been devoted to increasing the turbine inlet temperature regarding thermal efficiency and introducing combustion technology for suppression of pollutants such as nitrogen oxide (NOx). Exhaust gas recirculation (EGR) is recognized as a promising NOx inhibition technique mostly by reducing the combustion temperature. Recent industrial progress showed that EGR significantly reduced NOx emission even at the same turbine inlet temperature. An in-depth understanding of the combustion process is required for the development of low NOx combustors with EGR. In this work, a piloted axisymmetric …

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Deceptive Memory Systems, Christopher N. Gutierrez Dec 2017

Deceptive Memory Systems, Christopher N. Gutierrez

Open Access Dissertations

Unauthorized data destruction results in a loss of digital information and services, a devastating issue for society and commerce that rely on the availability and integrity of such systems. Remote adversaries who seek to destroy or alter digital information persistently study the protection mechanisms and craft attacks that circumvent defense mechanisms such as data back-up or recovery. This dissertation evaluates the use of deception to enhance the preservation of data under the threat of unauthorized data destruction attacks. The motivation for the proposed solution is two-fold. (i) An honest and consistent view of the preservation mechanisms are observable and often …

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