Engineering Commons^™

Developing Leading And Lagging Indicators To Enhance Equipment Reliability In A Lean System, Dhanush Agara Mallesh

Masters Theses

With increasing complexity in equipment, the failure rates are becoming a critical metric due to the unplanned maintenance in a production environment. Unplanned maintenance in manufacturing process is created issues with downtimes and decreasing the reliability of equipment. Failures in equipment have resulted in the loss of revenue to organizations encouraging maintenance practitioners to analyze ways to change unplanned to planned maintenance. Efficient failure prediction models are being developed to learn about the failures in advance. With this information, failures predicted can reduce the downtimes in the system and improve the throughput.

The goal of this thesis is to predict …

Automated Program Profiling And Analysis For Managing Heterogeneous Memory Systems, Adam Palmer Howard

Masters Theses

Many promising memory technologies, such as non-volatile, storage-class memories and high-bandwidth, on-chip RAMs, are beginning to emerge. Since each of these new technologies present tradeoffs distinct from conventional DRAMs, next-generation systems are likely to include multiple tiers of memory storage, each with their own type of devices. To efficiently utilize the available hardware, such systems will need to alter their data management strategies to consider the performance and capabilities provided by each tier.

This work explores a variety of cross-layer strategies for managing application data in heterogeneous memory systems. We propose different program profiling-based techniques to automatically partition program allocation …

Non-Equispaced Fast Fourier Transforms In Turbulence Simulation, Aditya M. Kulkarni

Masters Theses

Fourier pseudo-spectral method on equispaced grid is one of the approaches in turbulence simulation, to compute derivative of discrete data, using fast Fourier Transform (FFT) and gives low dispersion and dissipation errors. In many turbulent flows the dynamically important scales of motion are concentrated in certain regions which requires a coarser grid for higher accuracy. A coarser grid in other regions minimizes the memory requirement. This requires the use of Non-equispaced Fast Fourier Transform (NFFT) to compute the Fourier transform, by solving a system of linear equations.

To achieve similar accuracy, the NFFT needs to return more Fourier coefficients than …

Development Of Nuclear Underground Engineered Test Surrogates For Technical Nuclear Forensics Exploitation, Robert Boone Gilbreath

Masters Theses

A method for formulation and production of Nuclear UnderGround Engineered Test Surrogates (NUGETS) based on notional improvised nuclear device (IND) detonations in an underground environment analogous to the Nevada National Security Site (NNSS) is presented. Extensive statistical analyses of precursory geochemical and geophysical characteristics are combined with an augmented surrogate debris cooling technique and predictive IND contributions from the ORIGEN Fallout Analysis Tool. Precursory and resultant elemental compositions, cooling curve calculations, and visual comparison of NUGETS to genuine underground debris are reported. Application of NUGETS methodology to future studies in urban, underground post-detonation technical nuclear forensic (TNF) analysis is suggested.

Explorations Into Machine Learning Techniques For Precipitation Nowcasting, Aditya Nagarajan

Masters Theses

Recent advances in cloud-based big-data technologies now makes data driven solutions feasible for increasing numbers of scientific computing applications. One such data driven solution approach is machine learning where patterns in large data sets are brought to the surface by finding complex mathematical relationships within the data. Nowcasting or short-term prediction of rainfall in a given region is an important problem in meteorology. In this thesis we explore the nowcasting problem through a data driven approach by formulating it as a machine learning problem.

State-of-the-art nowcasting systems today are based on numerical models which describe the physical processes leading to …

Achieving Perfect Location Privacy In Wireless Devices Using Anonymization, Zarrin Montazeri

Masters Theses

The popularity of mobile devices and location-based services (LBS) have created great concerns regarding the location privacy of the users of such devices and services. Anonymization is a common technique that is often being used to protect the location privacy of LBS users. This technique assigns a random pseudonym to each user and these pseudonyms can change over time. Here, we provide a general information theoretic definition for perfect location privacy and prove that perfect location privacy is achievable for mobile devices when using the anonymization technique appropriately. First, we assume that the user’s current location is independent from her …

Time Domain Sar Processing With Gpus For Airborne Platforms, Dustin Lagoy

Masters Theses

A time-domain backprojection processor for airborne synthetic aperture radar (SAR) has been developed at the University of Massachusetts’ Microwave Remote Sensing Lab (MIRSL). The aim of this work is to produce a SAR processor capable of addressing the motion compensation issues faced by frequency-domain processing algorithms, in order to create well focused SAR imagery suitable for interferometry. The time-domain backprojection algorithm inherently compensates for non-linear platform motion, dependent on the availability of accurate measurements of the motion. The implementation must manage the relatively high computational burden of the backprojection algorithm, which is done using modern graphics processing units (GPUs), programmed …

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 …

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 …

Cloth-Air Partitioning Of Oxybenzone, Jonathan T. Hill

Masters Theses

"Clothing has been proven to be a significant accumulator of chemicals from the air. Semi-volatile organic compounds (SVOCs) have a high affinity towards textiles, and measuring the equilibrium partition coefficient between cloth and air (K_cloth-air) for SVOCs is crucial in predicting human exposure to these compounds. This study aims to quantify K_cloth-air for oxybenzone to contribute to a larger human exposure experiment carried out at the Technical University of Denmark (DTU). K_cloth-air for oxybenzone was calculated using data collected from the exposure chamber at DTU and from performing extractions of oxybenzone in fabric samples from the …

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 …

Classification Of Basal Cell Carcinoma Using Telangiectatic Vessels And Machine Learning, Hemanth Yadav Aradhyula

Masters Theses

“Basal cell carcinoma (BCC) is one of the most common types of skin cancer in the United States. Early detection of BCC by noninvasive techniques can decrease delay in treatment and save cost. A recent study estimated that 5.4 million cases of non-melanocytic skin cancer (NMSC) occur each year in the US. BCC accounts for 50% of NMSC cases. Telangiectasia, which appears in most BCCs is an important feature for identification of BCC for an automatic diagnostic system. In this thesis, three methods for detection of telangiectasia present in dermoscopy lesion image (DI) were proposed. Detected telangiectasia in DI was …

A Study Of The Potential Applications Of Am241, And Determining The Feasibility Of Using Gamma Spectroscopy For Future Physical Validation, Eric A. Feissle

Masters Theses

“Am241 is typically produced via Pu241 decay in a uranium fueled reactor. Presence of Am241 can be used as the age estimation tool for spent fuel, which is a focus of this thesis along with the interest of the measurement and the ratio of production rates of Am241’s activation products; Americium-242 and its first excited state of Americium-242m. MCNP models of the core and BEGe 3825 detector were built. These models were compared with established and physical measurements of gamma/x-ray standards that were available at the reactor. Thermal fluxes at 200 kW for potential foils centered in the source holder …

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, …

Hydrogeochemical Controls On Reactive And Nonreactive Solute Transport In Heterogenous Porous Media, Mahta Gholizadeh Ansari

Masters Theses

"This work examines how physical and chemical heterogeneity can affect reactive and non-reactive transport in porous media. The effect of heterogeneity of the porous media is investigated both on dissolution rate of magnesite and attenuation time of nonreactive contaminants in non-reactive media. Various spatial distribution were created using statistical parameters in PETREL.A total of 6793 transport modeling simulations were run using CrunchFlow. Lasso regression was used to select most significant features and those features are then used in linear regression and deep learning models.

The magnesite dissolution simulations were performed under different permeability ratios (magnesite /sand permeability) and inlet pH. …

Study Of Surface Complexation And Mineral Dissolution During Water-Rock Interaction In High Salinity Waterflooding At Elevated Temperatures, Sameer Salasakar

Masters Theses

"High salinity waterflooding for carbonate reservoirs is efficient and cheap method used for improved oil recovery. Various mechanisms have been proposed including adsorption/desorption on rock surface, mineral dissolution and precipitation, multicomponent ion exchange, interfacial tension reduction, fine migration and double layer expansion. These all process alter the wettability which leads to improved oil recovery.

Objective of this study was to understand processes that occur during water-rock interaction when high salinity water is flooded into the reservoir. In this work, effect of temperature on water-rock interaction is studied along with effect of pH and specific surface areas of calcite at normal …

A Bounded Actor-Critic Algorithm For Reinforcement Learning, Ryan Jacob Lawhead

Masters Theses

"This thesis presents a new actor-critic algorithm from the domain of reinforcement learning to solve Markov and semi-Markov decision processes (or problems) in the field of airline revenue management (ARM). The ARM problem is one of control optimization in which a decision-maker must accept or reject a customer based on a requested fare. This thesis focuses on the so-called single-leg version of the ARM problem, which can be cast as a semi-Markov decision process (SMDP). Large-scale Markov decision processes (MDPs) and SMDPs suffer from the curses of dimensionality and modeling, making it difficult to create the transition probability matrices (TPMs) …

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 …

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 …

Assessment Of Rockfall Rollout Risk Along Varying Slope Geometries Using The Rocfall And Crsp Software, Mariam S. Al E'Bayat

Masters Theses

"Most routes in mountainous areas suffer from rock falling, rolling and bouncing risk. There are many computer programs concerned with simulating the rockfall problem, and whereas they have the same purpose, they however differ in the input data that's needed to simulate the problem, and they also differ in the way of processing and kind of output.

This study used Rocfall® and the Colorado Rockfall Simulation Program (CRSP®) to simulate sixty-three models of varying slope geometry, where only the slope geometry is changed with the same material properties for both the slope and the rocks.

Both programs were fast and …

Deformation Processes At The Leading Edge Of The Sevier Fold And Thrust Belt, Southwest Utah, William Joseph Michael Chandonia

Masters Theses

"Deformation processes leading to formation and abandonment of 'triangle zones' along the leading edge of the Sevier fold and thrust belt are investigated near Kanarraville, Utah through construction of a detailed geologic map and cross-section along Spring Creek. Here the eastern limb of the Kanarra fold, a Sevier structure, is well exposed along the Hurricane Cliffs due to uplift and erosion of the footwall of the Hurricane Fault. The east-verging Kanarra fold changes from upright to overturned within Spring Creek. Within the fold limb, parasitic folds, minor thrust faults, and duplex structures result in local tectonic overthickening of units and …

Overview Of Co₂ Leakage Problems And Sealants For Co₂ Leakage Remediation, Shudai Peng

Masters Theses

"Excessive Carbon Dioxide (CO₂) emission has become a serious issue and caused lots of environmental problems. Carbon Capture and Storage (CCS) program has been developed to reduce the CO₂ content in the atmosphere. CO₂ storage has been targeted mainly on depleted oil or gas reservoirs and deep saline aquifers. However, leakage could occur through wellbores, cap rocks, formation faults, and fractures during and after CO₂ injection. To minimize the risk, different types of sealants have been investigated to prevent CO₂ leaks. The aim of this thesis is to provide a comprehensive review of the materials which could be used as …

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 …