Digital Commons Network^™

Stochastic Model For Solar Sensor Array Data, Faris Alfaris

Masters Theses

Statistical approaches are often used in time series analysis, for example, to predict the future trend of a time series. Trend forecasting can be applied in many time related parameters such as: solar radiation, generation of electricity and other variables related to time series to improve the efficiency and to set the design requirements. Since the design of any solar energy system requires knowledge of the availability of solar radiation data at the location of interest. Therefore, this research seeks the application of a statistical model to fit the solar radiation time series and predict the future values. There are …

Depth Profiling Of Pahs Treated With Activated Carbon Using In-Situ Spme, Ryan D. Stringer

Masters Theses

"Novel and efficient methods to measure the bioavailability of hydrophobic organic contaminants (HOCs) in contaminated sediments will play an important role in the acceptance of alternative sediment remediation strategies. In this project, solid phase microextraction (SPME) fibers, protected in perforated steel tubes, were used as in situ passive samplers to measure the treatment of activated carbon (AC) in polycyclic aromatic hydrocarbon (PAH) contaminated sediment. Contaminated sediment was treated with two modes of AC waterjet amendment. In the first treatment, a single 2-min injection was shot into the center of a test vessel and in the second treatment, multiple 7-sec injections …

Transport Of A Methamphetamine Surrogate Through Painted Drywall And Accumulation In Insulation, Nishanthini Vijayakumar Shakila

Masters Theses

"Methamphetamine is a drug of abuse in the United States and it is frequently produced in residential "meth labs." During a specific cooking stage called "salting out", a high concentration of methamphetamine is released into the air and can accumulate on and within indoor surfaces. Even after remediation, methamphetamine and other chemicals can be released into the occupied space by diffusion and desorption from insulation and painted drywall. To better understand the emission characteristics of methamphetamine, the diffusion coefficient of n- isopropylbenzylamine (NIBA; an isomer and surrogate for methamphetamine) was measured in latex painted drywall. To quantify the diffusion coefficient, …

Optimization Of Process Planning For Focused Ion Beam Machine In Nano-Manufacturing, Sushrut Shekhar Naik

Masters Theses

"The current revolution witnessed by nanotechnology is facing several challenges such as manufacturing of nano sized devices economically on a large scale. Focused ion beam (FIB) technology is one of the widely used approaches for nano-manufacturing due to its versatile nature. It provides accurate machining and process repeatability and has a range of applications. Major challenges for the current FIB process are the tradeoffs between quality, the processing time, and the long planning time. This research provides a pathway to eliminate the current problems facing nanotechnology. Using MATLAB and the Helios 600 FIB/SEM instrument available, modeling and analyses are carried …

Effects Of Coal Comminution In Relation To Waterjet And Selected Feed Properties, Yaqing Li

Masters Theses

"The necessity to develop a viable alternative to oil means that the development of coal-water fuels (CWF) has become increasingly important. However, the existing methods of comminution to prepare ultrafine particles for CWF are very inefficient. Consequently, a number of novel methods of comminution have been investigated in order to increase the efficiency of the process.

In this research, a new method of comminution using a high-pressure waterjet has been tested to produce ultrafine particle sizes necessary for efficient CWF process. To establish the fundamental performance of the waterjet mill, the influence of the operational pressure, standoff distance, feed size, …

Bond, Transfer Length, And Development Length Of Prestressing Strand In Self-Consolidating Concrete, Krista Beth Porterfield

Masters Theses

"Due to its economic advantages, the use of self-consolidating concrete (SCC) has increased rapidly in recent years. However, because SCC mixes typically have decreased amounts of coarse aggregate and high amounts of admixtures, industry members have expressed concerns that the bond of prestressing strand in SCC may be compromised. While the bond performance of prestressing strand in a new material such as SCC is an important topic requiring investigation, the results are only applicable if the research is completed on strands with similar bond quality as the strands used in the field. Therefore, the objectives of this research program were …

Sputter Deposition Of Thin-Film Capacitors Onto Low Temperature Co-Fired Ceramic Substrates, Jack Murray

Masters Theses

"Single layer thin film capacitor structures were fabricated on the surface of low temperature co-fired ceramic (LTCC) substrates using sputter deposition. The capacitor structures had areas between ~10⁴ µm² to ~10⁶ µm² and featured ~200 nm Al or Pt electrodes with 150-1500 nm Al₂O₃ dielectric layers. Impedance analysis and current-voltage testing were carried out to determine the effect of electrode material and dielectric thickness upon capacitor performance. Capacitance values for devices with Al electrodes ranged from ~10 to ~700 pF, depending on capacitor area and dielectric thickness, and the fit to expected values was better than devices with Pt or …

3d Spatio-Temporal Analysis For Compressive Sensing In Magnetic Resonance Imaging Of The Murine Cardiac Cycle, Brice Aaron Hirst

Masters Theses

"This thesis consists of two major contributions, each of which has been prepared in a conference paper. These papers will be submitted for publication in the SPIE 2013 Medical Imaging Conference and the ASEE 2013 Annual Conference.

The first paper explores a three-dimensional compressive sensing (CS) technique for reducing measurement time in MR imaging of the murine (mouse) cardiac cycle. By randomly undersampling a single 2D slice of a mouse heart at regular time intervals as it expands and contracts through the stages of a heartbeat, a CS reconstruction algorithm can be made to exploit transform sparsity in time as …

Cooperative Power Control Approaches Towards Fair Radio Resource Allocation For Wireless Network, Liuju Wu

Masters Theses

"Performance optimization in wireless networks is a complex problem due to variability and dynamics in network topology and density, traffic patterns, mutual interference, channel uncertainties, etc. Opportunistic or selfish approaches may result in unbalanced allocation of channel capacity where particular links are overshadowed. This degrades overall network fairness and hinders a multi-hop communication by creating bottlenecks. A desired approach should allocate channel capacity proportionally to traffic priority in a cooperative manner. This work consists of two chapters that address the fairness share problem in wireless ad hoc, peer-to-peer networks and resource allocation within Cognitive Radio network. In the first paper, …

Fabrication Of Complex Ceramic Parts With Sacrificial Material Using Freeze-Form Extrusion Fabrication, Diego Armando Garcia MontañO

Masters Theses

"An additive manufacturing process called Freeze-form Extrusion Fabrication (FEF) was developed in this study to fabricate complex ceramic parts that require the use of sacrificial materials. The aqueous paste of alumina (Al₂O₃) was used as the main material, with solids loadings as high as 50 vol. % and water as the main liquid medium. Methyl cellulose, with a 10 vol. % solids loading and 90 vol. % water content, was used as the sacrificial material. The freeze-form extrusion machine has multiple extruders (extrusion devices) capable of fabricating parts from multiple materials without mixing them. The dynamic process of extruding alumina …

Using Lidar As A Monitoring Device To Calculate Volume Of Rockfall Over Time, Travis James Kassebaum

Masters Theses

"There are many natural hazards which threaten the stability of highway infrastructure and the safety of motoring public. Rockfall and unstable slopes are one of the major concerns. This thesis describes a method which safely and accurately evaluates rockfall on rock outcrops through the use of Light Detection and Ranging (LiDAR) data. LiDAR is an imaging technology which can be used to measure and evaluate possible rock outcrop hazards such as: rockfall, rock-avalanches, debris flows, and landslides. LiDAR produces a three dimensional point cloud of millions of points which gives spatial data on the scanned object, accurate to millimeters, in …

Generic Kinematic Simulation For Verification Of Laser Deposition Tool Paths, Sweta Dhaveji Chakravadhanula

Masters Theses

"The development of 3D visual simulation tool for machine simulation is a key approach in saving time and reducing cost. It is an important step before a manufacturing operation is performed on a part, as a tool to detect collision and validate the operation results. There are several kinds of manufacturing equipment being used and hence there is a need for the development of a generalized method to visually simulate a variety of machines. This paper presents the research conducted on describing machine configuration in a generic format which not only gives useful information, but can also be used as …

Chemical Risk In Early Design, Carlton Ashley Washburn

Masters Theses

The purpose of this thesis is to present a methodology to identify risks in the chemical product development process, including fortification of the failure mode taxonomy by including chemical failures. This work will enable comprehensive risk analysis in technology-based products that have a chemical based subsystem, such as those used in the lithography process in the semiconductor industry. This research broadened the failure mode taxonomy by identifying chemical failures from publications in the semiconductor industry. These failures were analyzed to determine the rudimentary failure modes in each case. The newly identified failure modes were added to the failure mode taxonomy. …

Effects Of High Volume Fly Ash And Powder Activators On Plastic And Hardened Concrete Properties, Drew Alexander Davis

Masters Theses

This study was performed to examine the effects of high volumes of Class C fly ash modified by powder activators upon the plastic and hardened properties of concrete. In a companion study, five Missouri area cements and five Class C fly ashes were examined for incompatibilities, with the most and least reactive combinations being scaled up to full scale concrete testing. Two baseline concrete mixtures were examined, the only difference in mixtures being the sources of portland cement and fly ash. Fly ash replacement was examined at 50% and 70% replacement (by total cementitious mass). Three powder activators were used …

Lattice Residuability, Philip Theodore Thiem

Masters Theses

"Residuated lattices form the basis of certain kinds of logical interpretations. Also, complete commutative integral zero-bounded residuated lattices are used as a set of truth values for fuzzy logic values, Which are more general than the traditional bounded interval introduced by Zadeh. At times, it is important to know whether or not the lattice can be residuated in the first place. This thesis reviews the literature in lattice residuability and adds more observations. Specifically, (1) bounded chains and top-residuated lattices are show [sic] to be residuable, and (2) additional conditions necessary for residuability are established"--Abstract, page iii.

A Comparison Of Near-Infrared And Visible Imaging For Surveillance Applications, Kathryn Nicole Rodhouse

Masters Theses

"A computer vision approach is investigated which has low computational complexity and which compares near-infrared and visible image systems. The target application is a surveillance system for pedestrian and vehicular traffic. Near-infrared light has potential benefits including non-visible illumination requirements. Image-processing and intelligent classification algorithms for monitoring pedestrians are implemented in outdoor and indoor environments with frequent traffic. The image set collected consists of persons walking in the presence of foreground as well as background objects at different times during the day. Image sets with nonperson objects, e.g. bicycles and vehicles, are also considered. The complex, cluttered environments are highly …

Integration Of Multiple Vision Systems And Toolbox Development, Rohit Vijay Bapat

Masters Theses

"Depending on the required coverage, multiple cameras with different fields of view, positions and orientations can be employed to form a motion tracking system. Correctly and efficiently designing and setting up a multi-camera vision system presents a technical challenge. This thesis describes the development and application of a toolbox that can help the user to design a multi-camera vision system. Using the parameters of cameras, including their positions and orientations, the toolbox can calculate the volume covered by the system and generate its visualization for a given tracking area. The cameras can be repositioned and reoriented using toolbox to generate …

Trace Element Accumulation In Rice :Effects Of Soil Arsenic, Irrigation Management, Phosphate Application And Iron Oxide Amendment, Eric Michael Farrow

Masters Theses

A concern is growing over the accumulation of trace contaminants in rice, a plant which has been estimated to supply 50% of the caloric intake to the world's population. Contamination with arsenic (As) and other trace elements have been shown in many areas including the U.S. and rice intake poses a potential risk to human health. This research investigated the accumulation of selected trace elements including arsenic (As), selenium (Se), molybdenum (Mo) and cadmium (Cd) in as many as six rice cultivars and two control soils common to the south central U.S. A field study was completed to evaluate the …

Coaxial Cable Bragg Grating, Jie Huang

Masters Theses

"In order to ensure the continued safe and reliable operation of various civil structures, such as dams, bridges, and buildings, in situ strain monitoring is of great importance, especially for structures that may experience large strains. A new coaxial cable Bragg grating (CCBG) is developed as a strain sensor and the sensor's capacity for large range strain measurement is demonstrated for the first time. The sensor device is comprised of regularly spaced periodic discontinuities along a coaxial cable. The discontinuities are fabricated using a computer numerical controlled (CNC) machine to drill holes in the cable. Each discontinuity generates a weak …

Methods Of Optimizing The Gas Exchange Process To Improve Fuel Efficiency Of Small Carbureted Spark Ignition Engines, Cory Hannibal Huck

Masters Theses

"Fuel efficiency of internal combustion engines long has been a topic of concern. Much effort has been made to optimize the fuel efficiency of large automotive type engines. However, for small engine manufactures subject to tight cost constraints, this has only recently become an area of great focus. A method by which the fuel efficiency of an engine can be improved is through optimization of the intake process. Specifically, reductions in flow losses and the choice of appropriate valve event timings can provide ways to make gains towards more fuel efficient operation. The challenge arises when the focus is on …

Advanced Moisture Modeling Of Polymer Composites, Nathan Robert Roe

Masters Theses

"Composite materials absorb moisture from the environment and over time this moisture absorption affects the mechanical performance of the material. In order to determine the long-term moisture effects on the component, representative parts must be tested after having been exposed to an accelerated moisture-conditioning environment. This accelerated environment simulates the worst-case exposure conditions that a part might experience. Currently accepted methodologies for analyzing the time required to condition specimens are limited, only allowing simple geometry and an assumption that diffusivity rates are independent of the flow path or direction. Therefore, a more advanced finite element method is desired. In the …

A Novel Cantilever For Bi-Harmonic Atomic Force Microscopy, Muthukumaran Loganathan

Masters Theses

"Tapping mode (TM) AFM is a popularly used AFM technique in which an oscillating sharp tip mounted on a micro cantilever is used to probe the surface of interest with nanoscale resolution by making intermittent (tapping) contact with the surface. Any change in surface profile affects the tip amplitude, and is detectable only if it results in an amplitude change that is significant enough to be measured by the laser detector. Hence, it is desirable to have a micro cantilever that is sensitive to surface changes so as to provide sharper images and better surface resolution.

In the first part …

Design Of A Vortex Induced Vibration Based Marine Hydro-Kinetic Energy System, Varun Michael Lobo

Masters Theses

"Hydrokinetic energy harvesting based on vortex induced vibration (VIV) of a bluff body is discussed. VIV is defined as the vibration incurred on a bluff body due to an external fluid flowing over it. These vibrations are the results of boundary layer separation from the surface of the body. An optimized VIV generator has been developed, that utilizes a non-contact type linear magnetic device for generation of energy. The cylinder was chosen such that at the mass ratio (m*) was always lower than the critical mass (m*_critical= 0.52). The studies were based on two complementary …

Height Dependent Laser Metal Deposition Process Modeling, Patrick M. Sammons

Masters Theses

"Laser Metal Deposition (LMD) is used to construct functional parts in a layer-by-layer fashion. The heat transfer from the melt region to the solid region plays a critical role in the resulting material properties and part geometry. The heat transfer dynamics can change significantly as the layers increase, depending on the geometry of the sub layers. However, this effect is unaccounted for in previous analytical models, which are only valid for a single layer. This thesis develops a layer dependent model of the LMD process for the purpose of designing advanced layer-to-layer controllers. A lumped-parameter model of the melt pool …

Logistics Modeling And Project Management Practices For Contingency Basing, Amanda Jo Gealy

Masters Theses

"Contingency basing is a critical factor in mission success but requires significant logistical and commander support. Designing and constructing a camp that is safe, secure, and self-sustaining can be a difficult task for a Contingency Basing engineering manager. The infrastructure for basic needs such as electricity, fuel, water, food, and waste management is critical and needs to be flexible.

This research focuses on assisting the Contingency Basing engineering manager in designing and constructing a feasible base camp using project management and modeling tools. Measuring scalability and resiliency with in the contingency base was studied as well. The methodology concentrates on …

Hot Channel Determination And Burnup Analysis Of Missouri University Of Science And Technology Research Nuclear Reactor, Kelly Christopher Rogers O'Bryant

Masters Theses

"A burnup analysis has been performed on the Missouri University of Science and Technology (Missouri S&T) Research Nuclear Reactor (MSTR). With use of the Monte Carlo neutronics depletion code MCNPX, burned material was input into a neutronics model (burned model) in order better simulate MSTR core characteristics. Simulated burnup values of ²³⁵U for the past twenty years of MSTR operations totaled 14.266 grams, slightly less than the 14.527 grams reported by the reactor staff. A distribution of ²³⁵U was simulated and a burnup map was developed.

Using the updated fuel material, the hot channel of the current configuration of the …

Distributed And Collaborative Watermarking In Relational Data, Prakash Kumar

Masters Theses

"Watermarking relational data is an important topic in the field of copyright protection, given the increasing prevalence of piracy and illegal duplication of databases. While there exists solutions for watermarking relational data, the problems that arise due to multiple ownership (two or more) of databases have not been acknowledged. This research focuses on developing a novel watermarking scheme to counter the problems. The watermarking scheme proposed necessitates the owners of the database in consideration to come together to perform the watermarking process. The scheme can be applied to insert watermarks in both numerical and categorical data. The watermarking scheme is …

Displacement Of Heavy Oil By Carbon Dioxide In A Tube, Mohammed Almabrouk Ali Ahmad

Masters Theses

"After using primary and secondary oil recovery methods, about two third of the original oil in place is left behind in the reservoir. Enhanced oil recovery (EOR) methods are being used to recover that oil. CO₂ flooding is one of the EOR methods that is used to recover the oil. The interest here lies in recovery of heavy oils. The dissolution of CO₂ in oil reduces oil viscosity and swells it, making it easier to displace the oil. FLUENT is used to solve the problem of CO₂ displacing heavy oil in a tube. Different velocities/capillary numbers (Ca) and …

Bond Behavior Of High-Volume Fly Ash And Self-Consolidating Concrete, Trevor Jay Looney

Masters Theses

"The main objective of this study was to determine the effect on bond performance of high-volume fly ash (HVFA) concrete and self-consolidating concrete (SCC). The HVFA concrete test program consisted of comparing the bond performance of two concrete mix designs with 70% cement replacement with Class C fly ash relative to a Missouri Department of Transportation (MoDOT) standard mix design. The SCC test program consisted of comparing the bond performance of normal and high strength SCC with their respective MoDOT standard mix designs.

Two test methods were used for bond strength comparisons. The first was a direct pull-out test based …

Capture Zone Modeling For Photovoltaic Microgrid Powered Pump And Treat Remediation, John Patrick Conroy

Masters Theses

"Remediation systems protect human health and the environment by removing harmful contaminants from the environment. Pump and treat groundwater remediation systems typically rely on utility power to continuously pump contaminated groundwater to an above ground treatment unit. However, the use of renewable energy (solar and wind) for a pump and treat remediation system can reduce the output of harmful greenhouse gases and the need for coal-based utility power.

This paper describes a hypothetical renewable energy powered pump and treat remediation system that uses an off-grid photovoltaic array to power a submersible solar water pump. The pump operates on an intermittent …