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Full-Text Articles in Engineering

Recovery Of Phosphate Minerals From Plant Tailings Using Direct Froth Flotation Process, Ashraf Alsafasfeh Jan 2017

Recovery Of Phosphate Minerals From Plant Tailings Using Direct Froth Flotation Process, Ashraf Alsafasfeh

Masters Theses

"The wastes produced from phosphate industry presents many challenges due to the economic and environmental impacts of their disposal. In the meantime, scarcity of high-grade phosphate ores persuades researchers to find novel methods of upgrading these wastes (secondary sources) and recycling them in the production plant circuit. The goal of this study is to investigate the potential to upgrade the phosphorus content in the tailing produced from a phosphorous production plant using direct froth flotation process. Characterization studies such as X-ray diffraction (XRD), scanning electron microscopy (SEM), and mineral liberation analysis (MLA) were first conducted to identify the mineralogical and …


A Comprehensive Analysis Of Lost Circulation Materials And Treatments With Applications In Basra's Oil Fields, Iraq: Guidelines And Recommendations, Husam Hasan Alkinani Jan 2017

A Comprehensive Analysis Of Lost Circulation Materials And Treatments With Applications In Basra's Oil Fields, Iraq: Guidelines And Recommendations, Husam Hasan Alkinani

Masters Theses

"Lost circulation materials (LCM's) have been widely used to avoid or stop losses. Due to a large number of current available LCM's and their different applications, classification of LCM's is very important. The most recent LCM classification was published around 50 years ago, and this paper intends to fill this gap with an updated classification including conventional and new technologies. Lost circulation materials and treatments are re-classified into various categories based on their appearance, applications, chemical and physical properties.

Wells in Basra's oil fields are highly susceptible to lost circulation problems when drilling through the Dammam, Hartha, and Shuaiba formations. …


Predicting The Impact Of Data Corruption On The Operation Of Cyber-Physical Systems, Erik David Burgdorf Jan 2017

Predicting The Impact Of Data Corruption On The Operation Of Cyber-Physical Systems, Erik David Burgdorf

Masters Theses

"Cyber-physical systems, where computing and communication are used to fortify and streamline the operation of a physical infrastructure, now comprise the foundation of much of modern critical infrastructure. These systems are typically large in scale and highly interconnected, and span application domains from power and water distribution to autonomous vehicle control and collaborative robotics. Intelligent decision support in these systems is heavily reliant on the availability of sufficient and sufficiently correct data. Failure or malfunction of these systems can have devastating consequences in terms of public safety, financial losses, or both.

The research described in this thesis aims to predict …


Comparison Of ²⁵²Cf Time Correlated Induced Fission With Amli Induced Fission On Fresh Mtr Research Reactor Fuel, Jay Prakash Joshi Jan 2017

Comparison Of ²⁵²Cf Time Correlated Induced Fission With Amli Induced Fission On Fresh Mtr Research Reactor Fuel, Jay Prakash Joshi

Masters Theses

"The effective application of international safeguards to research reactors requires verification of spent fuel as well as fresh fuel. To accomplish this goal various nondestructive and destructive assay techniques have been developed in the US and around the world. The Advanced Experimental Fuel Counter (AEFC) is a nondestructive assay (NDA) system developed at Los Alamos National Laboratory (LANL) combining both neutron and gamma measurement capabilities. Since spent fuel assemblies are stored in water, the system was designed to be watertight to facilitate underwater measurements by inspectors. The AEFC is comprised of six 3He detectors as well as a shielded …


Liquid Pulsed Plasma Thruster Plasma Plume Investigation And Mr-Sat Cold Gas Propulsion System Performance Analysis, Jeremiah Daniel Hanna Jan 2017

Liquid Pulsed Plasma Thruster Plasma Plume Investigation And Mr-Sat Cold Gas Propulsion System Performance Analysis, Jeremiah Daniel Hanna

Masters Theses

"The plasma plume produced by a liquid pulsed plasma thruster is investigated using a Langmuir triple probe and a nude Faraday probe. The Langmuir triple probe failed to produce results which are suspected caused by the presence of ionic liquid in the plume resulting in shorting of the probe. The nude Faraday probe is able to record the ion current density which revealed a high level of inconsistency in the plasma plume. Ion current density recorded by the nude Faraday probe had a relative standard deviation of upwards of 100% of the mean value. Controlling the amount of propellant used …


The Effect Of Twist On The Mechanical Properties Of The Intervertebral Disc, Maxine Harvey-Burgess Jan 2017

The Effect Of Twist On The Mechanical Properties Of The Intervertebral Disc, Maxine Harvey-Burgess

Theses and Dissertations (Comprehensive)

Introduction: Intervertebral disc (IVD) herniation is a common injury to the IVD and a frequent source of low back pain. IVD herniation occurs when the nucleus pulposus migrates through both the inter- and intralamellar matrices of the annulus fibrosus (AF). There are a number of mechanical risk factors associated with herniation, including repetitive flexion and twist. In vivo, twist combined with repetitive flexion has been associated with increased experience of low back pain and herniation. Additionally, in vitro, when repetitive flexion is combined with twist, IVD herniation occurs more easily than repetitive flexion alone. However, the mechanisms behind …


Diffusion And Mechanical Characterization Of Nanoparticle-Enabled Diffusion Controlled Materials, Joseph Louis Volpe Jan 2017

Diffusion And Mechanical Characterization Of Nanoparticle-Enabled Diffusion Controlled Materials, Joseph Louis Volpe

Masters Theses

"Nanoparticle-enabled diffusion control has been shown to rapidly refine multiphase microstructures during slowly cooled casting. This thesis characterizes the diffusion and the mechanical properties of nanoparticle-enabled diffusion controlled materials. To characterize diffusion properties, in situ characterization is performed to verify the nanoparticle enabled diffusion control mechanism. Materials with nanoparticles were observed to decrease the diffusion coefficient by at least one order of magnitude under similar melting conditions as compared to materials without nanoparticles. To understand mechanical properties, the nanoparticles that assembled at the growing interface were characterized under mechanical tensile stress. Nanoparticle-enabled interfaces were observed to improve the interface bond …


Sparse Emission Source Microscopy For Rapid Emission Source Imaging, Ling Zhang Jan 2017

Sparse Emission Source Microscopy For Rapid Emission Source Imaging, Ling Zhang

Masters Theses

"In Paper I, Sparse Emission Source Microscopy (ESM) methodology will be introduced and discussed for the localization of major EMI radiation sources in complex and large systems. Traditional ESM method takes abundant and uniformly-distributed scanning points on the scanning plane using a robotic system, which can provide high-quality source images but consumes too much time. This section presents a sparse and nonuniform sampling technique for ESM, which is more time-efficient in identifying major radiation sources, even though the image quality is sacrificed. The feasibility of sparse sampling is mathematically proved, and it is shown that increasing number of points increases …


A New Reinforcement Learning Algorithm With Fixed Exploration For Semi-Markov Decision Processes, Angelo Michael Encapera Jan 2017

A New Reinforcement Learning Algorithm With Fixed Exploration For Semi-Markov Decision Processes, Angelo Michael Encapera

Masters Theses

"Artificial intelligence or machine learning techniques are currently being widely applied for solving problems within the field of data analytics. This work presents and demonstrates the use of a new machine learning algorithm for solving semi-Markov decision processes (SMDPs). SMDPs are encountered in the domain of Reinforcement Learning to solve control problems in discrete-event systems. The new algorithm developed here is called iSMART, an acronym for imaging Semi-Markov Average Reward Technique. The algorithm uses a constant exploration rate, unlike its precursor R-SMART, which required exploration decay. The major difference between R-SMART and iSMART is that the latter uses, in addition …


Processing And Properties Of Wc-Based Cu-Ni-Mn-Zn Metal Matrix Composites Produced Via Pressureless Infiltration, Paul M. Brune Jan 2017

Processing And Properties Of Wc-Based Cu-Ni-Mn-Zn Metal Matrix Composites Produced Via Pressureless Infiltration, Paul M. Brune

Masters Theses

"This research focuses on the processing and properties of tungsten carbide-based (WC-based) Cu-Ni-Mn-Zn metal matrix composites (MMCs) fabricated by pressureless infiltration. The first goal of this project was to test the wettability of Cu-Ni-Mn and Cu-Ni-Mn-Zn on various carbides. The sessile drop technique was employed to determine if they were suitable candidates for pressureless infiltration. The carbides investigated were TaC, WC, B4C, and SiC. It was determined that both alloys had contact angles of less than 70⁰ on TaC, WC, and B4C, which is one requirement for pressureless infiltration. However, both alloys reacted with B4C to …


Developing A Website For The Sword Of The Spirit Using An Agile Development Approach, James Smith Jan 2017

Developing A Website For The Sword Of The Spirit Using An Agile Development Approach, James Smith

Senior Honors Theses and Projects

This creative project was created using an agile development process. Working in coordination with an organization called the Sword of the Spirit, a website was developed for their use. Using the agile approach, multiple iterations of the project were created and brought back to the organization for testing and feedback. The website was developed and is currently working here: https://sites.google.com/view/sosovemight/home.

For this project, a website, administrative email, and data collection and storage process were created. Security was added to ensure only registered profile holders would be able to view the information on the website. This was developed solely for the …


Entropy-Based Performance Analysis Of Jet Engines; Methodology And Application To A Generic Single-Spool Turbojet, Mohammad Abbas Jan 2017

Entropy-Based Performance Analysis Of Jet Engines; Methodology And Application To A Generic Single-Spool Turbojet, Mohammad Abbas

Masters Theses

"Recently developed methodology that provides the direct assessment of traditional thrust-based performance of aerospace vehicles in terms of entropy generation (i.e., exergy destruction) is modified for stand-alone jet engines. This methodology is applied to a specific single-spool turbojet engine configuration. A generic compressor performance map along with modeled engine component performance characterizations are utilized in order to provide comprehensive traditional engine performance results (engine thrust, mass capture, and RPM), for on and off-design engine operation. Details of exergy losses in engine components, across the entire engine, and in the engine wake are provided and the engine performance losses associated with …


Advanced Buffer Materials For Indoor Air Co₂ Control In Commercial Buildings, Pavithra Ethi Rajan Jan 2017

Advanced Buffer Materials For Indoor Air Co₂ Control In Commercial Buildings, Pavithra Ethi Rajan

Masters Theses

"The following describes a novel passive approach to control the indoor CO2 levels in enclosed spaces, primarily focusing on commercial buildings. Amine impregnated silica sorbents were identified as suitable candidates and synthesized; the amine loading ratio was varied to create a range of materials. These samples along with other commercial zeolite candidates have been tested over a range of CO2 concentrations to determine the CO2 adsorption capacity in laboratory systems and under simulated room conditions. The research work also focuses on the CO2 desorption capacity of the candidate adsorbents. The desorption is allowed to occur gradually …


2-D And 3-D Mapping Of Soil And Rock Structure In Karst Terrain Of Southwestern Missouri Using The Non-Invasive Electrical Resistivity Tomography Method (Ert), Diya Ali Ahmad Alfuqara Jan 2017

2-D And 3-D Mapping Of Soil And Rock Structure In Karst Terrain Of Southwestern Missouri Using The Non-Invasive Electrical Resistivity Tomography Method (Ert), Diya Ali Ahmad Alfuqara

Masters Theses

"Electrical resistivity tomography data were acquired in an extensively karstic area of southwestern Missouri. The interpretation of the electrical resistivity tomography data was constrained by multichannel analysis of surface wave data and limited boring control. The objective of the study was to determine if variations in the moisture content of the soil and shallow rock are related to ground surface topography. Analysis of the acquired electrical resistivity tomography data showed that resistivity values of soil and shallow rock beneath and in proximity to identified natural and man-made surface run-off pathways are typically low compared to the resistivity values of soil …


High Speed Serial Link Design With Multi-Level Signaling And Characteristic Impedance Extraction From A Transmission Line With Meshed Ground Planes, Jiayi He Jan 2017

High Speed Serial Link Design With Multi-Level Signaling And Characteristic Impedance Extraction From A Transmission Line With Meshed Ground Planes, Jiayi He

Masters Theses

"Channel bandwidth and manufacturing process have become two limitations in today's high speed designs. In order to overcome the channel bandwidth limitation, multilevel signaling is seen as one of the ways to achieve higher data rates. Using multilevel signaling as the coding scheme will impose new challenges in high speed serial link design. Due to manufacturing limitations, only transmission lines with meshed ground planes are allowed in some applications. Meshed power and ground planes have been widely used in today's flexible PCB designs to satisfy repeatability installation and reliability requirements.

In Section 1, high speed serial link design with PAM4 …


Plug-In Hybrid Electric Vehicle Load Profile Estimation With Opportunity Charging, Reza Kazem Sharif Sharifi Jan 2017

Plug-In Hybrid Electric Vehicle Load Profile Estimation With Opportunity Charging, Reza Kazem Sharif Sharifi

Masters Theses

"This thesis focuses on the load profile analysis of the plug-in hybrid electric vehicles (PHEV), examining two different scenarios. In the first scenario, the battery of a PHEV is charged at the final arrival time, and the arrival time analysis has a minute accuracy. In the second scenario, opportunity charging, which refers to the stop-time between two trips, is used for charging the battery of the vehicle. However, if the stop-time between two trips is less than 30 minutes, the duration is not counted as an opportunity charging and it is filtered. The results of the two scenarios are compared, …


Micro-Grid Implementation Of A Rooftop Photovoltaic System, Pranav Nitin Godse Jan 2017

Micro-Grid Implementation Of A Rooftop Photovoltaic System, Pranav Nitin Godse

Masters Theses

"In recent years, solar power has been a popular form of renewable energy. This research conducts a cost analysis in implementing a rooftop photovoltaic system as part of an energy management schema for a university campus. The proposed system would be installed on the roof of one of the largest buildings on campus at Missouri University of Science and Technology, Toomey Hall; the objective function of the research involves reducing dependence on conventional energy sources on campus. Toomey Hall houses the Department of Mechanical and Aerospace Engineering (MAE) and is the largest academic unit on campus. Considering the vast expanse …


The Viability Of Advantg Deterministic Method For Synthetic Radiography Generation, Andrew Albert Bingham Jan 2017

The Viability Of Advantg Deterministic Method For Synthetic Radiography Generation, Andrew Albert Bingham

Masters Theses

"Time sensitive and high resolution image simulations are needed for synthetic radiography generation. The standard stochastic approach requires lengthy run times with poor statistics at higher resolutions. The investigation of the viability of a deterministic approach to synthetic radiography image generation was explored. The aim was to analyze a computational time decrease over the stochastic method. ADVANTG was compared to MCNP in multiple scenarios including a Benchtop CT prototype, to simulate high resolution radiography images. By using ADVANTG deterministic code to simulate radiography images the computational time was found to decrease over 10 times compared to the MCNP stochastic approach"--Abstract, …


Spectrum Analyzer Based Phase Measurement For Emi Scanning Applications, Shubhankar Marathe Jan 2017

Spectrum Analyzer Based Phase Measurement For Emi Scanning Applications, Shubhankar Marathe

Masters Theses

"Often Electromagnetic Interference (EMI) scanning applications require phase and magnitude information for the creation of equivalent radiation models and for far-field predictions. Magnitude information can be obtained using a spectrum analyzer (SA), which is relatively inexpensive compared to phase resolving instruments such as oscilloscopes (scope) and vector network analyzers (VNA). The study focusses on the development of a near-field scanning method using a SA to measure the phase of the device under test (DUT) signals.

The first part deals with the development of the method in software simulation tools and testing it under standard test conditions. The second part deals …


Generating Fast And Accurate Compliance Reports For Various Data Rates, Srinath Penugonda Jan 2017

Generating Fast And Accurate Compliance Reports For Various Data Rates, Srinath Penugonda

Masters Theses

"As the demands on the industry data rates have increased there is a need for interoperable interfaces to function flawlessly. Added to this complexity, the number of I/O data lines are also increasing making it more time consuming to design and test. This in general leads to creating of compliance standards to which interfaces must adhere. The goal of this theses is to aid the Signal Integrity Engineers with a better and fast way of rendering a full picture of the interface compliance parameters.

Three different interfaces at various data rates were chosen. They are: 25Gbps Very Short Reach (VSR) …


Mold Flux Crystallization And Mold Thermal Behavior, Elizabeth Irene Peterson Jan 2017

Mold Flux Crystallization And Mold Thermal Behavior, Elizabeth Irene Peterson

Masters Theses

"Mold flux plays a small but critical role in the continuous casting of steel. The carbon-coated powder is added at the top of the water-cooled copper mold, over time it melts and infiltrates the gap between the copper mold and the solidifying steel strand. Mold powders serve five primary functions: (1) chemical insulation, (2) thermal insulation, (3)lubrication between the steel strand and mold, (4) absorption of inclusions, and (5)promotion of even heat flux. All five functions are critical to slab casting, but surface defect prevention is primarily controlled through even heat flux. Glassy fluxes have high heat transfer and result …


Novel Approaches For Efficient Stochastic Computing, Ramu Seva Jan 2017

Novel Approaches For Efficient Stochastic Computing, Ramu Seva

Masters Theses

"This thesis is comprised of two papers, where the first paper presents a novel approach for parallel implementation of SC using FPGA (Field Programmable Gate Array). This paper makes use of the distributed memory elements of FPGAs (i.e., look-up-tables -LUTs) to achieve this. An attempt has been made to build the stochastic number generators (SNGs) by using the proposed LUT approach. The construction of these SNGs has been influenced by the Quasi-random number sequences, which provide the advantage of reducing the random fluctuations present in the pseudo-random number generators such as LFSR (Linear Feedback Shift Register) as well as the …


Data Analysis Of Lane Merge And Lane Shift Sign Configurations In A Freeway Workzone, Satwinder Singh Thind Jan 2017

Data Analysis Of Lane Merge And Lane Shift Sign Configurations In A Freeway Workzone, Satwinder Singh Thind

Masters Theses

"In this study, driver responses to alternative lane shift and lane merge signs are analyzed and compared using a driving simulation system. In particular, driver responses to the lane merge signs proposed by the Missouri Department of Transportation (MoDOT) are compared to the current lane merge signs recommended by the Manual on Uniform Traffic Control Devices (MUTCD) and driver responses to the lane shift signs proposed by MoDOT are compared to current lane shift signs recommended by MUTCD. The driving simulation system is composed of a driving simulator and a PC with data recording program such that the position coordinates, …


Extending Time Series Forecasting Methods Using Functional Principal Components Analysis, Isaac Michael Wagner-Muns Jan 2017

Extending Time Series Forecasting Methods Using Functional Principal Components Analysis, Isaac Michael Wagner-Muns

Masters Theses

"Traffic volume forecasts are used by many transportation analysis and management systems to better characterize and react to fluctuating traffic patterns. Most current forecasting methods do not take advantage of the underlying functional characteristics of the time series to make predictions. This paper presents a methodology that uses Functional Principal Components Analysis (FPCA) to create smooth and differentiable daily traffic forecasts. The methodology is validated with a data set of 1,813 days of 15 minute aggregated traffic volume time series. Both the FPCA based forecasts and the associated prediction intervals outperform traditional Seasonal Autoregressive Integrated Moving Average (SARIMA) based methods"--Abstract, …


Dc-Dc Converter Based Photovoltaic Simulator With A Double Current Mode Controller, Weichao Zhang Jan 2017

Dc-Dc Converter Based Photovoltaic Simulator With A Double Current Mode Controller, Weichao Zhang

Masters Theses

"This thesis presents the performance of a DC-DC converter based with current mode controller photovoltaic (PV) simulator which emulates the output characteristics of a real PV module. A portable PV simulator prototype of 85 W is examined in terms of its steady state IV curve matching capacity and the convergence time corresponding to step change in current source load, voltage source load, and insolation levels. The current-voltage (IV) characteristics of the PV module are implemented as a look-up-table (LUT) which determines the reference output current from measured output voltage. A Thevenin Equivalent Method approach to PV arrays analysis is also …


Vegetation Based Assessment And Monitoring Tools For Landfill Leachate Treatment And Fugitive Plumes, Rahul Sukharia Jan 2017

Vegetation Based Assessment And Monitoring Tools For Landfill Leachate Treatment And Fugitive Plumes, Rahul Sukharia

Masters Theses

"Solid waste and leachate generation from solid waste landfills has a legacy of detrimental and toxic impacts on the environment. Disposal practices are expensive, failure prone and have not been able to keep up with the pace of disposal of toxic compounds. In general, a landfill acts as a "bathtub" with infiltration of water through the landfill cover into the landfill, reacting with the waste and transferring toxic components into the leachate. Irrigating the evapotranspiration (ET) covers with leachate collected from the landfill has been developed and applied. Such methods can keep the leached pollutants in a loop, which reduces …


Evaluation Of Swelling And Re-Swelling Of Preformed Particle Gels (Ppg) When Exposed To Co₂, Sujay Suresh Jan 2017

Evaluation Of Swelling And Re-Swelling Of Preformed Particle Gels (Ppg) When Exposed To Co₂, Sujay Suresh

Masters Theses

"Long term water/gas flooding induces high permeability channels in reservoirs. Reservoir heterogeneity becomes the most prominent challenge faced in mature oil fields. Gel treatment has been a proven solution to counter the problem of reservoir heterogeneity, to provide in-depth treatment and improve the sweep efficiency for reservoirs. Preformed particle gels (PPGs) were developed as an alternative to in-situ gels as they preferentially penetrate and shutoff high permeability zones, leaving the low permeability zones undamaged. These gels have been predominantly used in water flooding projects, but have not been employed in carbon dioxide (CO2) flooding projects. CO2 Resistant …


Evaluation Of Non-Chromate Passivations On Electroplated Γ-Phase Zinc Nickel, Steven Michael Volz Jan 2017

Evaluation Of Non-Chromate Passivations On Electroplated Γ-Phase Zinc Nickel, Steven Michael Volz

Masters Theses

"This research focused on the corrosion response and electrochemical behavior of electroplated low hydrogen embrittlement alkaline γ-phase zinc nickel with passivation layers. The motivation was the need to replace hexavalent chromium conversion coatings in military grade electrical systems with a more environment friendly alternative. The passivation layers were employed for the purpose of mitigating corrosion attack while maintaining low contact resistance. Trivalent chromium-based passivations and cerium-based passivations were compared against the currently used hexavalent chromium conversion coating. The coating systems were compared using electrochemical impedance spectroscopy, cyclic potentiodymanic scans, salt spray exposure testing, electrical resistance measurements, microstructure analysis, and compositional …


Comparison Of Voltage Regulation Between Sst And Conventional Transformers In High Penetration Pv Power Systems, Gautham Ashokkumar Jan 2017

Comparison Of Voltage Regulation Between Sst And Conventional Transformers In High Penetration Pv Power Systems, Gautham Ashokkumar

Masters Theses

"Solid state transformers (SST) are power electronic transformers combined with high-frequency conventional transformers and control circuitry capable of delivering high performance and flexible power control capabilities. This thesis focuses on analyzing the performance of SSTs in a distribution system with photovoltaic (PV) injection. In order to validate the performance of SSTs, average value models are used on the IEEE 34 bus distribution feeder network scaled to 12.47 kV. SST voltage profiles on the load side are analyzed and the unity power factor capabilities are demonstrated. This is followed by the study of voltage profiles on the primary side of the …


Shortest-Distance And Minimum-Cost Self-Charging Path Problems: Formulations And Application, Marc Monroe Teeter Jan 2017

Shortest-Distance And Minimum-Cost Self-Charging Path Problems: Formulations And Application, Marc Monroe Teeter

Masters Theses

"In this study, self-charging paths for an electric bus are analyzed. Wireless-power-transfer technologies, when integrated on a road network, enable dynamic charging of electric vehicles. Roads implemented with a wireless-power-transfer technology are referred to as electric-roads in this study. Electric vehicles traversing on electric-roads, therefore, can be dynamically charged. This can further eliminate the need for static charging, i.e., the electric vehicle will not need to stop for charging.

This thesis analyzes the design of transit routes for an electric-bus so that the electric-bus is charged by only electric-roads. Specifically, the focus is on designing a path, which passes through …