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Improving Plasma Actuator Performance At Low Pressure, And An Analysis Of The Pointing Capabilities Of Cubesats Using Plasmonic Force Propulsion (Pfp) Thrusters, Paul Daniel Friz

Masters Theses

"This thesis details the work done on two unrelated projects, plasma actuators, an aerodynamic flow control device, and Plasmonic Force Propulsion (PFP) thrusters, a space propulsion system for small satellites.

The first half of the thesis is a paper published in the International Journal of Flow Control on plasma actuators. In this paper the thrust and power consumption of plasma actuators with varying geometries was studied at varying pressure. It was found that actuators with longer buried electrodes produce the most thrust over all and that they substantially improved thrust at low pressure. In particular actuators with 75 mm buried …

Effect Of Stress Concentrations On Fatigue Of Composite And Metallic Structures, Ross Henry Falen

Masters Theses

"The complex shapes of hydrokinetic turbine blades can include part features such as a fillet, step, or hole. Situations can arise where two part features, such as a hole and a fillet, may be in close proximity which can introduce stress concentrations within the blade structure, adversely affecting the structure's life. Because the interaction between the part features isn't well known, fatigue data is needed to determine the proper analysis.

In this thesis, two separate topics are discussed and investigated. The first topic deals with stress concentrations in hydrokinetic turbine blades. Several blade designs were tested and improved upon to …

A Cloud Brokerage Architecture For Efficient Cloud Service Selection, Venkata Nagarjuna Dondapati

Masters Theses

"The expanding cloud computing services offer great opportunities for consumers to find the best service and best pricing, which however raises new challenges on how to select the best service out of a huge pool. It is obvious time-consuming for consumers to collect the necessary information and analyze all service providers to make the decision. It is also a highly demanding task from a computational perspective, because the same computations may be conducted repeatedly by multiple consumers who have similar requirements. In this paper, we propose a novel brokerage-based architecture in the cloud, where the cloud brokers is responsible for …

Analysis Of Factors Responsible For Life Degradation Of Led Traffic Indicators In The State Of Missouri, Snehal Satish Digraskar

Masters Theses

"Traffic lights using state-of-the-art LED illumination use 90 percent less electricity and offer a much longer service life and durability than their incandescent counterparts. Taking advantage of the countless benefits, cities around the country have been replacing traditional filament-based traffic signal bulbs with LEDs for years. However, the degradation of LEDs and hence the replacement strategy, are a concern which is faced by most of the Departments of Transportation. The thesis work sponsored by MoDOT, presents the replacement strategy developed based on the field study of LED indicators in Missouri. Three types of analysis are performed with multiple data point …

Application Of Electrically Invisible Antennas To The Modulated Scatterer Technique, Dylan Andrew Crocker

Masters Theses

"The Modulated Scatterer Technique (MST) has shown promise for applications in microwave imaging, electric field mapping, and materials characterization. Traditionally, MST scatterers consist of dipole antennas centrally loaded with a lumped element capable of modulation (commonly a PIN diode). By modulating the load element, the signal scattered from the MST scatterer is also modulated. However, due to the small size of such scatterers, it can be difficult to reliably detect the modulated signal. Increasing the modulation depth (a parameter related to how well the scatterer modulates the scattered signal) may improve the detectability of the scattered signal. In an effort …

Comparison Of Core Control And Geophysical Investigations, Silica Sand Deposits, Dawmat Al Jandal, Al Jawf At Saudi Arabia, Ghassan Salem Alsulaimani

Masters Theses

"This thesis is a summary of a comprehensive geophysical investigation in southern Dawmat Al Jandal, Al Jawf in Saudi Arabia. This research demonstrates that the acquisition of both core control and geophysical data is superior to the acquisition of core control alone. Coring is expensive and is limited in subsurface coverage. Geophysical surveying, however, is a relatively rapid and cost-effective means of deriving information about the subsurface between core holes. Ground penetrating radar (GPR), Multichannel Analysis of Surface Waves (MASW), and Seismic Refraction methods were used as exploration techniques to locate surficial mineral deposits within the study area.

During the …

Comparison Of Costs Of Personal Protective Equipment For All Workers To Avoid Costs Of Fall Accidents, Sultan Noori Al-Karawi

Masters Theses

"The construction industry is one of the most important industries in the United States. It is the biggest contributor in the growth of the U.S. economy. Despite the great achievements and prominent role for this sector in the U.S. economy, the construction industry is suffering from neglect and dereliction by related government institutions and private companies. This neglect led to formation of a negative image about the construction industry that has caused a deep impact in productivity and economic growth. One of the reasons is a high percentage of accidents that occur within the construction industry which leads to injuries …

Theoretical Analysis Of Shape Separation Of Particles Using Flow Field-Flow Fractionation, Mehrdad Alfi

Masters Theses

"Size separation of spherical and rod-like particles in Flow Field-flow Fractionation was investigated theoretically. The effect of cross flow migration and rod orientation was also investigated as a new mode of study. It has been shown that the rod local orientation makes different diffusivity values in comparison with spherical particles and helps particle separation. Additionally, a new mechanism of lift-hypelayer mode was used for rod-like particles which can be compared with steric mode of spherical particles. This mechanism is said to be due to hydrodynamic interaction of rod-like particle with wall and with other rods.

As a measure of axial …

Quantitative Modeling Of Reliability And Survivability For Cyber-Physical Power Systems, Murtadha Nabeel Albasrawi

Masters Theses

"Critical infrastructure systems are increasingly reliant on cyber infrastructure that enables intelligent real-time control of physical components. This cyber infrastructure utilizes environmental and operational data to provide decision support intended to increase the efficacy and reliability of the system and facilitate mitigation of failure. Realistic imperfections, such as corrupt sensor data, software errors, or failed communication links can cause failure in a functional physical infrastructure, defying the purpose of intelligent control. As such, justifiable reliance on cyber-physical critical infrastructure is contingent on rigorous investigation of the effect of intelligent control, including modeling and simulation of failure propagation within the cyber-physical …

An Analytical Pressure Model To Guide Downhole Sensor Placement For Carbon Dioxide Sequestration Monitoring, Yilin Mao

Masters Theses

"Injecting CO₂ into saline aquifers is currently the most viable approach to mitigate global greenhouse gas effect. Various monitoring techniques are required to achieve 99% accuracy in determining the location of the injected CO₂ plume. Sensor locations are critical to the monitoring quality necessary to meet this requirement but have scarcely been discussed. The pressure profile needs to be modeled accurately at the initial stage of CO₂ injection to guide sensor locations. The objective of this thesis was to develop an analytical solution for CO₂ sequestration based on time and distance. This will guide the locations of downhole pressure sensors …

The Description Of An Effective Sinkhole Investigation Approach: A Case Study Of Two Sites In Greene County, Missouri, Stanley Chinedu Nwokebuihe

Masters Theses

"Karst topographies pose danger to the environment. The associated gradual subsidence or sudden collapse of the ground can lead to loss of lives and damage to property. A sinkhole is the subsidence or collapse of the overburden into subsurface cavities. Sinkholes develop in different sizes, shapes and rates all over the world especially in areas where the bedrock can be dissolved by percolating slightly acidic surface water.

Different methods have been used to investigate sinkholes. Boring is the most common of these methods. But the boring technique is quite inefficient; it only provides information of the subsurface conditions at the …

Processing And Feature Analysis Of Atomic Force Microscopy Images, Xiao Pan

Masters Theses

"Atomic force microscopy (AFM) is a versatile and powerful tool for imaging and measuring small-scale objects such as nanoparticles, single molecules, semiconductor devices and living cells. The basic operation of an AFM can be to utilize a sharp cantilever tip that interacts with the sample surface and senses the local force between the tip and sample surface. Based on the physical interaction between the AFM and the small-scale object for image acquisition, there can be a number of artifacts, including curvature distortion (bowing effects), high-frequency or low-frequency noise, which may not be easily recognized by users accustomed to conventional microscopy. …

Fair And Optimal Resource Allocation In Wireless Sensor Networks, Vinodhini Ravikumar

Masters Theses

"There is a large amount of research in wireless networks focuses on optimization of either network routing and power control alone. In contrast, this work aims at jointly optimizing the transmission power and routing path selection in order to optimize allocation of resources in interference constrained wireless environment. Moreover, we consider a multipath routing where multiple alternative paths are employed to transmit data between the end nodes. One of modern communication techniques that it applies to a network coding, though not explicitly implemented in this work. The proposed approach is first analyzed theoretically using Lagrangian optimization for a three-node scenario. …

An Investigation Of Contaminant Metal Distribution And Mineral Speciation In The Soil Near The Buick Recycling Division Smelter, Iron County, Missouri, Krista Nicole Rybacki

Masters Theses

"Trace metal contamination studies were conducted near the Buick Resource Recycling Division. This study used sequential extraction, total digestion, X-Ray Diffraction (XRD), and Scanning Electron Microscopy-Energy Dispersive Spectroscopy (SEM-EDS) to study trace metals in two soil cores. Sequential extraction analysis of the soil cores revealed that lead was associated with either iron or manganese oxides. Zinc and copper were bound to soil components, extracted mainly from organics, sulfides, and clays. Total digestion results compared favorably to the sum of the sequential extraction results for lead, thus validating the sequential extraction methodology. The highest concentration observed for lead was 4,743 parts …

Emi Investigation And Modeling Of A Flat Panel Display, Satyajeet Shinde

Masters Theses

"It is often important to carry out EMI analysis in the design phase of an electronic product to predict the radiated emissions. An EMI analysis is important to predict if the product complies with the FCC regulations as well as to gain an understanding of the noise coupling and radiation mechanisms. EMI analysis and prediction of radiated emissions in electronic products that have an electrically large chassis, pose a challenge due to the presence of multiple resonant structures and noise-coupling mechanisms.

The study focusses on the investigation of the main noise coupling mechanisms, the approach and methods used for the …

Bond Performance Of Recycled Aggregate Concrete, Amanda Renee Steele

Masters Theses

"In recent decades, engineers have sought a more sustainable method to dispose of concrete construction and demolition waste. One solution is to crush this waste concrete into a usable gradation for new concrete mixes. This not only reduces the amount of waste entering landfills but also alleviates the burden on existing sources of quality natural concrete aggregates. The objective of this study was to determine to effect of replacing coarse natural aggregates for recycled concrete aggregates (RCA) on the bond strength between deformed mild reinforcing steel and surrounding concrete. Two different RCA replacement levels were considered, 50% and 100%, and …

Characterization Of A Plant Gene Family Expanded In Glycine Max, Lisa Snoderly-Foster

Masters Theses

"Glycine max, commonly named the cultivated soybean, is one of the oldest and most important food crops in the world. The study of the G. max genome provides valuable insight into the molecular mechanisms that govern its reproduction and environmental responsiveness, key factors in maximizing crop yield. Since the complete sequencing of the genome in 2010, the analysis has become faster and easier, especially with the development of numerous web-based, publically accessible bioinformatics tools.

This research effort utilizes these tools to characterize a small, unannotated G. max gene family. Although no definitive evidence was uncovered for the production of a …

Efficient Data Access In Mobile Cloud Computing, Siva Naga Venkata Chaitanya Vemulapalli

Masters Theses

"This thesis focuses on the development of efficient data transfer mechanism among mobile devices using Mobile cloud computing paradigm. Mobile cloud computing is coupling of mobile computing and cloud computing. In the Mobile cloud computing paradigm, users connect to cloud service providers over the Internet and leverage the cloud resources to perform their processing, storage and communication tasks. In this thesis, the focus is on communication tasks among mobile devices performed using Mobile cloud computing paradigm.

Communication or data sharing among mobile devices is often limited by proximity of the devices. This limitation can be removed by employing Mobile cloud …

Investigation Of Angiogenic Effects Of Bioactive Borate Glass Microfibers And Beads In A Rodent Model, Richard Jeffrey Watters

Masters Theses

"The primary objective of this research project was to evaluate the effects of three different compositions of bioactive glass microfibers (45S5, 13-93B3, and 13-93B3Cu) and bioactive glass beads (13-93, 13-93B3, and 13-93B3Cu) on angiogenesis in subcutaneous tissue in the SKH1 'hairless' mouse. Microvascular responses to the bioactive glass implants were investigated via three experimental approaches: noninvasive vital imaging of microvasculature in dorsal skin windows; quantitative histomorphometry of microvascular densities; and quantitative PCR measurements of mRNA expression of pro-angiogenic cytokines VEGF and FGF-2. The live imaging of dorsal skin window preparations in the hairless SKH1 showed the formation of a halo-like …

Computational Fluid Dynamics (Cfd) Modeling Of Proppant Transport In A Plug-And-Perf Completion With Different Perforation Phasing, Jinlin Zhang

Masters Theses

"Perf-and-plug is a completion technique commonly used in multistage fracturing. Fracture performance modeling assumes that fluid and proppant distributes uniformly among all perforations along the length of the wellbore in a plug and perf completion Crespo et al. (2012) has conducted a limited proppant flow experiment using a 63 foot stage, and three 0.42 inch, zero phased simulated perforations. His work demonstrates proppant does not distribute evenly, but the work is limited to a single perforation scheme.

In this study, Computational Fluid Dynamics (CFD) software has been used to simulate proppant transport and distribution in a single stage of a …

A Remote Sensing Investigation Of Elevated Sub-Horizontal Topographic Surfaces In The Wichita Mountains, Oklahoma, Liang Xue

Masters Theses

"Multiple elevated horizontal to sub-horizontal topographic surfaces are present in the Wichita Mountains, Oklahoma. Elevated topographic surfaces, developed primarily on granite bedrock with gentle slopes of 0.5 to 7⁰,were investigated using 1) Digital Elevation Models (DEMs) extracted from NAD 27 UTM coordinates, 2) Google Earth imagery, and 3) USGS topographic maps. In the western Wichita Mountains prominent topographic surfaces at elevations of 720 ± 5 m, 685 ± 5 m, and 660 ± 5 m are well preserved on at least four different mountains (e.g., Solder's Peak, King Mt.) and can be correlated with similar surfaces on at least seven …

Access Control Delegation In The Clouds, Pavani Gorantla

Masters Theses

"Current market trends need solutions/products to be developed at high speed. To meet those requirements sometimes it requires collaboration between the organizations. Modern workforce is increasingly distributed, mobile and virtual which will incur hurdles for communication and effective collaboration within organizations. One of the greatest benefits of cloud computing has to do with improvements to organizations communication and collaboration, both internally and externally. Because of the efficient services that are being offered by the cloud service providers today, many business organizations started taking advantage of cloud services. Specifically, Cloud computing enables a new form of service in that a service …

An Analysis Of Burn Cut Pull Optimization Through Varying Relief Hole Depths, Michael Robert Allen

Masters Theses

"In underground blasting, the pull of the initial cut is the limiting factor for the success of the rest of the round. By improving the pull of the first cut, a critical step is made towards improving the entire round. This project attempted to optimize a burn cut's effective pull by varying the depths of the relief holes in the burn, and then analyzing the results. In testing, relief holes were drilled to depths both shorter and longer than that of the cut's charged holes. The overall objective was to consistently achieve greater pull than in a standard burn, using …

An Empirical Study On Symptoms Of Heavier Internet Usage Among Young Adults, Saipreethi Vishwanathan

Masters Theses

"Understanding negative consequences of heavy Internet use on mental health is a topic that is gaining significant traction recently. A number of studies have investigated heavy Internet usage, especially among young adults in relation to online games, social media and email. While such studies do provide valuable insights, Internet usage so far has been characterized by means of self-reported surveys only that may suffer from errors and biases. In this paper, we report the findings of a two month empirical study on heavy Internet usage among students conducted at a college campus. The novelty of the study is that it …

Analysis Of A Ventilation Network In A Multiple Fans Limestone Mine, Ali Haghighat

Masters Theses

"As mining progresses the total resistance of an excavation is increased, the mine characteristic curve becomes steeper, and the operating point moves up the fan curve, reducing the total air quantity and increasing the system pressure. For multi-level ventilation networks with a number of fans the process can be tedious, and on a count of numerous dependent factors the optimal combination of fans is very hard to be achieved. The design of a ventilation network in conjunction with multi surface fans and booster fans entails a complex procedure.

The objective of this study is to provide a plan to improve …

Aspen Simulation Of Furfural And Hydroxymethylfurfural Production From Biomass, Zachary Daniel King

Masters Theses

"Biomass field liquefaction is a concept where green biomass is chemically treated to produce organic liquids using small-scale equipment in the field. If liquefaction occurs as the crop is harvested, the energy requirements for growing the biomass can be charged to the crop as if the biomass were left in the field. The energy in the organic liquid product is available at the expense of the energy required by the process. A simplified process was simulated using ASPEN to assess the energy production feasibility.

Acid catalyzed liquefaction of cellulose and hemicellulose solids produces furfural and hydroxymethylfurfural (HMF). The simulation assumed …

Assessment Of Contributing Factors To The Reduction Of Diarrhea In Rural Communities Of Para, Brazil, Lee Voth-Gaeddert

Masters Theses

"In developing communities the occurrence of diarrhea has been reported at elevated levels as compared to those communities in more developed regions. Diarrheal diseases were linked to over one million deaths in 2012 throughout the world. While multiple pathways are present for the transmission of diarrheal diseases, water has been the focus for many aid organizations. Point-of-use (POU) water treatment methods are a common tool used by aid organizations in efforts to provide potable water. The CAWST biosand filter is a POU tool that has shown removal effectiveness of pathogenic microorganisms ranging from 90-99%. However, minimal literature was found that …

Dephosphorylation Of Iqg1 By Cdc14 Temporally Regulates Actin Ring Formation, Daniel Patrick Miller

Masters Theses

"Cytokinesis is the final step in cell division when the cell separates the cytoplasm by contracting a ring composed of filamentous actin (F-actin) and type II myosin. Iqg1, an IQGAP family member, is an essential scaffolding protein in budding yeast (S. cerevisiae) required for actin recruitment to, and contraction of, the actomyosin ring. Actin is recruited by the calponin homology domain (CHD) in anaphase after Iqg1 is localized to the bud neck. Consensus sites for the cyclin-dependent kinase (CDK) Cdc28 were identified flanking the CHD. This led us to the hypothesis that phosphorylation of Iqg1 by Cdc28 negatively regulates actin …

Determination Of Minor And Trace Elements Concentration In Kidney Stones Using Elemental Analysis Techniques, Anjali Srivastava

Masters Theses

"The determination of accurate material composition of a kidney stone is crucial for understanding the formation of the kidney stone as well as for preventive therapeutic strategies. Radiations probing instrumental activation analysis techniques are excellent tools for identification of involved materials present in the kidney stone. The X-ray fluorescence (XRF) and neutron activation analysis (NAA) experiments were performed and different kidney stones were analyzed. The interactions of X-ray photons and neutrons with matter are complementary in nature, resulting in distinctly different materials detection. This is the first approach to utilize combined X-ray fluorescence and neutron activation analysis for a comprehensive …

Effects Of Indentation Speed And Water Saturation Level On The Behavior Of Roubidoux Sandstone, Azupuri Ayerikujei Kaba

Masters Theses

"The experiment conducted in this research was to determine the behavior of a porous rock under an indenter. To investigate this, medium-grained sandstone was subjected to a series of indentation tests. These tests were conducted under both dry and saturated conditions using a rounded conical indenter. In addition, tests were conducted at different indentation speeds. The test results were used to calculate the mechanical specific energy (SE) and specific penetration (SP). The porewater pressure evolution in the saturated sample was also monitored.

The tests and subsequent analyses reveal that saturation did not affect the specific energy when the indentation rate …