Engineering Commons^™

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 …

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

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 …

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

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, …

Characterization Of The Rectification Behaviour Of In-Amps And Estimating The Near Field Coupling From Smps Circuits To A Nearby Antenna Using Dipole Moments, Chunyu Wu

Masters Theses

"This thesis discusses two parts.

In the first part, the rectification behavior of popular instrumentation amplifiers is measured in both common mode and single-ended RF noise injection. It is recommended that AD8221 be used in common mode RF noise injection environment. And AD8220 and AD8429 are recommended in single-ended RF noise injection environment. The mechanism of RF noise rectification inside in-amps is also discussed. It is verified that rectification mainly happens at the non-inverting input of two op-amps in the first stage of an in-amp. The DC voltage difference between inverting input and non-inverting input of the in-amp is further …

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 …

A Physics-Based Approach For Power Integrity In Multi-Layered Pcbs, Biyao Zhao

Masters Theses

"Developing a power distribution network (PDN) for ASICs and ICs to achieve the low-voltage ripple specifications for current digital designs is challenging with the high-speed and low-voltage ICs. Present methods are typically guided by best engineering practices for low impedance looking into the PDN from the IC. A pre-layout design methodology for power integrity in multi-layered PCB PDN geometry is proposed in the thesis. The PCB PDN geometry is segmented into four parts and every part is modelled using different methods based on the geometry details of the part. Physics-based circuit models are built for every part and the four …

Processing, Microstructure, And Properties Of Engineered Diboride Structures, Connor Charles Wittmaier

Masters Theses

"The mechanical properties and processing parameters of boride ceramics in foam and laminate architectures were evaluated. The ceramic reticulated foam was produced through a polymer substrate replication technique and the hardness and compressive strength were tested. The laminate structure was tested to evaluate the flexure strength and work of fracture as a function of temperature.

The foam architecture was produced using a TiB₂ slurry coating on a polyurethane reticulated foam preform. Foams sintered to 2150⁰C displayed an average grain size of 8.9 ± 7.3 µm, and a hardness of 17.3 ± 2.4 GPa. Crush testing foams were sintered at …

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

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 …

Development Of A Variogram Approach To Spatial Outlier Detection Using A Supplemental Digital Elevation Model Dataset, Zane Daniel Helwig

Masters Theses

"When developing a ground water model, the quality of the dataset should first be evaluated. Spatial outliers can lead to predictions which are not representative of actual conditions. In order to isolate misrepresentative points, a method is presented which examines the experimental variogram of a ground water elevation dataset. To define a threshold variance between pairs of ground water elevation measures, ground elevation values from a digital elevation model (DEM) are used to determine a maximum reasonable variance expected to occur on the experimental variogram. To determine appropriate DEM parameters, a separate study was also done which observed characteristic behavior …

Long-Term Monitoring Of A Landslide In Stone County, Missouri Using High Precision Multi-Temporal Laser Scanning, Benjamin Michael Herries

Masters Theses

"A terrestrial laser scanning survey was conducted over the course of 1.5 years to test and validate a new target tracking method which characterizes the surface and subsurface behavior of soft slope landslides. Reflective spherical Styrofoam targets were mounted onto steel rods and driven into multiple levels of a landslide located in Stone County, Missouri. These targets were scanned a total of seventeen times over the course of the survey and were used as a proxy to measure the displacement of specific areas of the landslide. The three-dimensional point cloud data was processed through a software suite specifically developed to …

Imaging In Karst Terrain Using The Electrical Resistivity And Multichannel Analyses Of Surface Wave Methods, Ragab W. Jaafar

Masters Theses

"Electrical resistivity tomography and multi-channel analyses of surface waves data were acquired at a study area in Phelps County in the south-central part of Missouri. The objectives of the investigation were fourfold: 1) to image the subsurface in the study area to a depth of 70 feet; 2) to compare the ERT images generated using both the dipole-dipole and Wenner-Schlumberger arrays; and 3) to assess how variations in the MASW array configuration affected MASW data quality; and 4) to compare the ERT-estimated depth to top-of-rock and the MASW-generated depth to top-of-rock.

The subsurface in the study area was imaged to …

Mining Asteroids For Volatile Resources: An Experimental Demonstration Of Extraction And Recovery, Egboche Christopher Unobe

Masters Theses

"Gaseous compounds trapped within carbonaceous asteroids may prove to be important targets for prospective space miners in the near-term. Volatile release is from hydrated, hydroxylated and carbonated phases present, making such bodies attractive as feedstock for the production of H₂O, CO₂ and simple organic compounds. A source of these species in orbit provides an opportunity to locally produce space-craft propellant and other life-support gases through the application of In-situ Resource Utilization (ISRU).

For this study, an experimental vacuum system was modified and used to test the technical validity of radiatively heating asteroid simulants to extract contained gaseous …

Application Of Millimeter-Wave Differential Probe For Crack Detection On Riveted Structures, Kuang Ping Ying

Masters Theses

"This thesis proposes the use of a W-band wideband differential probe for crack detection on riveted structures, such as aircraft fuselage lap joints. Detection of crack at its early stage (surface-breaking) is particularly important to prevent the development of a fatigue crack. This probe utilizing millimeter-wave frequencies serves as a viable candidate on detecting surface-breaking cracks, as it can be employed in measurements in a non-contact fashion, while allowing for high spatial-resolution images and the abilities to penetrate through dielectric materials (paint), making it attractive for detecting small cracks. In previous works, a V-band differential probe has shown promise for …

Cathodic Protection Measurement Through Inline Inspection Technology Uses And Observations, Briana Ley Ferguson

Masters Theses

"This research supports the evaluation of an impressed current cathodic protection (CP) system of a buried coated steel pipeline through alternative technology and methods, via an inline inspection device (ILI, CP ILI tool, or tool), in order to prevent and mitigate external corrosion. This thesis investigates the ability to measure the current density of a pipeline's CP system from inside of a pipeline rather than manually from outside, and then convert that CP ILI tool reading into a pipe-to-soil potential as required by regulations and standards. This was demonstrated through a mathematical model that utilizes applications of Ohm's Law, circuit …

Effect Of Fracture Heterogeneity On Proppant Transport And Settling Mechanism, Dhurgham Abdulameer Kadhim

Masters Theses

"Proppant transport modeling through fractures with slickwater fluid systems assumes uniform and homogeneous fracture widths by implying constant fluid behavior at wall boundaries. Hydraulic fracturing mineback operations have demonstrated that induced fractures are heterogeneous and varying in width. This work investigates the impact of fracture width heterogeneity, roughness, and leak-off on ceramic proppant transport and settling, using proppant distribution concepts of Equilibrium Dune Level (EDL) and equilibrium Dune Length (EDX). Experimental work was conducted to investigate the impact of fracture width heterogeneity by varying fracture width along two plexiglass sheets. To mimic actual hydraulic fractures, the injection side was designed …

Developing Restoration Schemes For A Road Transportation Network In The Event Of A Disaster, Ebin Antony

Masters Theses

"Transportation systems such as rail, road, and waterways are key component of critical infrastructure systems, providing connectivity between other components to enable the production and distribution of goods and services. During large scale disasters such as earth quakes and floods, this connectivity is disrupted, restricting or completely halting the flow of goods and services. To ensure that the connectivity between the different modes of transportation are restored in an aftermath of these disruptions, the interdependence between them and the importance of individual elements to the overall connectivity have to be studied and formulated to develop a system-level restoration plan. This …

Geomechanical Analysis Of The Wellbore Instability Problems In Nahr Umr Formation Southern Iraq, Haider Qasim Mohammed

Masters Theses

"Wellbore instability problems play a major rule of increasing nonproductive time (NPT) during drilling processes. In most cases, the cost of drilling a well can be reduced by designing a suitable operational window using geomechanical models. Several wellbore instability problems have been encountered during drilling Nahr Umr Formation in an oil field in southern Iraq. These problems include but are not limited to, mechanical stuck, caving, and tight holes. Data from twenty vertical wells are investigated to reveal the major factors that control the instability problems and to design an optimum mud window. A geomechanical model is developed to determine …

Depth Determination Method For A Trailer-Truck Test-Bed, Aditya Thakur

Masters Theses

"A camera is considered as a good sensing device to obtain visual information from its surrounding environment. In a three dimensional space, a camera has a two dimensional plane. Projection of an object on this plane creates a two dimensional projection and loses information of the third dimension. A single projection is not enough to retrieve the lost third dimensional information about the object. Thus it makes it difficult to use a single camera as a sensing instrument. In this project, we have developed a method that determines the three dimensional information using a single camera. The method utilizes an …

Nuclei Segmentation Using Level Set Method And Data Fusion For The Cin Classification, Ravali Edulapuram

Masters Theses

"This paper deals with the automation of the detection of the cervical cancer through histology images. This process is divided into two parts, corresponding to segmentation and data fusion. The segmentation and classification of the cervical epithelium images is done using hybrid image processing techniques. The digitized histology images provided have a pre-cervical cancer condition called cervical intraepithelial neoplasia (CIN) by expert pathologists. Previously, image analysis studies focused on nuclei-level features to classify the epithelium into the CIN grades. The current study focuses on nuclei segmentation based on the level set segmentation and fuzzy c-means clustering methods. Morphological post-processing operations …

Nuclei Segmentation Of Histology Images Based On Deep Learning And Color Quantization And Analysis Of Real World Pill Images, Sudhir Sornapudi

Masters Theses

"Medical image analysis has paved a way for research in the field of medical and biological image analysis through the applications of image processing. This study has special emphasis on nuclei segmentation from digitized histology images and pill segmentation. Cervical cancer is one of the most common malignant cancers affecting women. This can be cured if detected early. Histology image feature analysis is required to classify the squamous epithelium into Normal, CIN1, CIN2 and CIN3 grades of cervical intraepithelial neoplasia (CIN). The nuclei in the epithelium region provide the majority of information regarding the severity of the cancer. Segmentation of …

Detection Of Mine Roof Failure Using Inexpensive Lidar Technology, Ali Abdullah M. Alzahrani

Masters Theses

"Slope, Roof, and mine wall stability problems are some of the main reasons for deaths at U.S. surface or underground mining. The safety instruments were not enough to prevent that failure or even predict it before it occurs. However, the cost of such a tool that can be helpful in detecting roof failures is very high and not reachable in most instances.

The present study investigates the feasibility of using the M16 Leddar Evaluation Kit to detect the roof failure in mines. The M16 Leddar Evaluation kit cost is between 300$-800$, so it is the reachable price if it provides …

Analysis Of Outsourcing Data To The Cloud Using Autonomous Key Generation, Mortada Abdulwahed Aman

Masters Theses

"Cloud computing, a technology that enables users to store and manage their data at a low cost and high availability, has been emerging for the past few decades because of the many services it provides. One of the many services cloud computing provides to its users is data storage. The majority of the users of this service are still concerned to outsource their data due to the integrity and confidentiality issues, as well as performance and cost issues, that come along with it. These issues make it necessary to encrypt data prior to outsourcing it to the cloud. However, encrypting …

Preformed Particle Gel Conformance Control Performance In Partially Opened Fracture And Fully Opened Fracture Systems, Ghith Ali Ahmed Biheri

Masters Theses

"Conformance problems, such as reservoir heterogeneity can result in a significant decrease in oil recovery, and an excessive water production. Millimeter particle gels (PPG) have been used as conformance control agents to plug open fractures, however, very little research has been conducted to study their ability to plug partially open fractures. This research studies the ability of the PPG to plug partially open fracture to improve conformance and increase recovery in oil reservoirs. Rectangular Sandstone cores were used to conduct the experiments. Fracture widths used include 2, 3.5, 5 mm. For each fracture width, four gel strengths were used; gel …

Bioaccessibility Of Lead From Lead-Contaminated Soil Upon Phosphate Amendment Using A Physiologically-Based Extraction Test, Samantha Jo Dicenso

Masters Theses

"Lead is known to cause health problems in humans, especially children, and an effective in‐situ remediation option has been sought for years. Adding phosphoric acid (PA) to contaminated soil causes a reaction that binds the lead to phosphate to produce pyromorphite (Pb₅(PO₄)₃Cl), a form of lead believed to be non‐bioavailable; however, field trials have given varied results (Bosso et al 2008; Munksgaard and Lottermoser 2011; Tang et al. 2009). One explanation for these results might be the impact of the agent used to raise pH after phosphoric acid addition. In order to examine this explanation soil was collected from the …

Cyber-Physical Manufacturing Cloud: An Efficient Method Of Building Digital Twin For 3d Printer By Adapting Mtconnect Protocol, Liwen Hu

Masters Theses

"The common modeling of a virtual machine is using an information model to describe the physics of machines. The integration of digital twins into productive cyber-physical cloud manufacturing (CPCM) systems imposes strict requirements such as reducing overhead and saving resources for the systems. In this paper, we investigate a new method for building cloud-based digital twins (CBDT), which can be adapted to the CPCM platform. Our method helps reduce computing resources in the processing center and guarantees the fastest speed of the interactions between the human users and physical machines. We introduce a knowledge resource center (KRC) built on a …

Combination Of Bmp-2 And Relaxin To Induce Osteogenesis In Vivo, Sahitya Injamuri

Masters Theses

"Bone grafts are a common procedure for treating craniofacial injuries such as trauma, surgery, and reconstruction. Autografts and allografts have limitations which encourages the use of synthetic bone grafts. While synthetic bone grafts, such as hydroxyapatite (HA) microspheres, are advantageous for their cost and reproducibility, they lack the cells and growth factors needed for proper osteoinduction. Bone morphogenetic protein-2 (BMP-2) has been shown to increase the osteoinduction of grafts but the effective dose is above physiological levels and causes undesired effects on the body. Relaxin has been shown to enhance BMP-2's ability to induce bone formation in vitro and thus …

Quantifying Ceramic Proppant Transport In Complex Fracture Networks, Vivekvardhan Reddy Kesireddy

Masters Theses

"Water fracs have become an essential part of unconventional reservoirs to create deeper fracture networks. Proppant transport in water fracs is challenging in terms of fluids ability to carry the proppant deeper into these fracture networks. This experimental study investigates the impact of the flow rates, fracture widths and complexity controlling the ability of proppant to flow into complex fracture networks. This research attempts to nullify the knowledge gap in understanding width heterogeneity in primary and secondary fractures. This study speaks for settling pattern and proppant transport through a slot flow model with a unique approach to understand stage wise …