Engineering Commons^™

Investigation Of Long Term Pillar Stability In An Abandoned Gypsum Mine Based On Dissolution Models, Mohammadhossein Sadeghiamirshahidi

Dissertations, Master's Theses and Master's Reports

The abandoned Domtar Mine in Grand Rapids, MI underlies Interstate I-196. The mine operated for over 140 years, mining a 30-meter-deep, four-meter thick gypsum seam. In 2000, the mine was abandoned with the removal of the mine’s dewatering pumps allowing groundwater to flood the mine. The initial flooding resulted in saturating the mine pillars along with some amount of pillar dissolution. Overtime, gypsum dissolution would cease as the water becomes saturated with the gypsum dissolution products. The mine, however, is located adjacent to the Grand River and has groundwater moving through the mine resulting in the potential for continuing dissolution. …

Development Of The Coil Volume Method For Time-Domain Simulation Of Internal Faults In Transformers, Elizaveta Egorova

Dissertations, Master's Theses and Master's Reports

A power transformer is a very important and expensive asset for a utility. As for any other power equipment, the transformer is subject to internal faults. The extent of transformer damage depends on the fault duration. Therefore, the protective relays should provide for sensitivity, selectivity, and speed of operation to minimize the effects of damaging conditions. High sensitivity of the relay allows it to identify internal faults quickly. However, the relay should not jeopardize the normal operation of the transformer. To determine desirable relay settings, a transformer model for simulation of internal faults is required.

Transformer models, shown in the …

Enhancing The Resolution Of Imaging Systems By Spatial Spectrum Manipulation, Wyatt Adams

Dissertations, Master's Theses and Master's Reports

Much research effort has been spent in the 21st century on superresolution imaging techniques, methods which can beat the diffraction limit. Subwavelength composite structures called ``metamaterials" had initially shown great promise in superresolution imaging applications in the early 2000s, owing to their potential for nearly arbitrary capabilities in controlling light. However, for optical frequencies they are often plagued by absorption and scattering losses which can decay or destroy their interesting properties. Similar issues limit the application of other superresolution devices operating as effective media, or metal films that can transfer waves with large momentum by supporting surface plasmon polaritons. In …

Modeling And Control Of Maximum Pressure Rise Rate In Rcci Engines, Aditya Basina

Dissertations, Master's Theses and Master's Reports

Low Temperature Combustion (LTC) is a combustion strategy that burns fuel at lower temperatures and leaner mixtures in order to achieve high efficiency and near zero NOx emissions. Since the combustion happens at lower temperatures it inhibits the formation of NOx and soot emissions. One such strategy is Reactivity Controlled Compression Ignition (RCCI). One characteristic of RCCI combustion and LTC com- bustion in general is short burn durations which leads to high Pressure Rise Rates (PRR). This limits the operation of these engines to lower loads as at high loads, the Maximum Pressure Rise Rate (MPRR) hinders the use of …

Modeling Of Thermal Dynamics In Chevrolet Volt Gen Ii Hybrid Electric Vehicle For Integrated Powertrain And Hvac Optimal Operation Through Connectivity, Nehal Doshi

Dissertations, Master's Theses and Master's Reports

Integrated thermal energy management across system level components in electric vehicles (EVs) and hybrid electric vehicles (HEVs) is currently an under explored space. The proliferation of connected vehicles and accompanying infrastructure in recent years provides additional motivation to explore opportunities in optimizing thermal energy management in EVs and HEVs with the help of this newly available connected vehicle data. This thesis aims to examine and analyze the potential to mitigate vehicle energy consumption and extend usable driving range through optimal control strategies which exploit physical system dynamics via controls integration of vehicle subsystems.

In this study, data-driven and physics-based models …

Electro-Optic Antenna Elements For Passive Phased Array Radar, Evan Gawron

Dissertations, Master's Theses and Master's Reports

Passive phased antenna arrays are utilized in military and civilian radar systems to determine the received signal origination. Phased array placement for optimal reception is challenging due to the required supporting electronic hardware and the associated coaxial cabling that typically accompanies each antenna channel. Low noise amplifiers and frequency conversion hardware add size and complexity, limiting possible positions for phased array placement. Eliminating required phased array electronic subcomponents without sacrificing function would allow placement onto smaller agile platforms, such as unmanned systems and rapid deployment networks. Electro-optic (EO) antenna elements utilize an optical waveguide embedded between the antenna and ground …

Development Of A 2d Scr Catalyst On A Diesel Particulate Filter Model For Design And Control Applications To A Ultra Low Nox Aftertreatment System, Venkata Chundru

Dissertations, Master's Theses and Master's Reports

This research focuses on modeling and control of PM and NO_x in diesel engine exhaust using an SCR catalyst on a Diesel Particulate Filter (SCR-F). A 2D SCR-F model was developed that is capable of predicting internal states: 2D temperature, PM and NH₃storage distributions and filtration efficiency, pressure drop, PM mass retained in the PM cake and substrate wall and outlet NO, NO₂and NH₃concentrations. The SCR-F model was used to simulate a DOC + SCR-F + DOC + SCR ultra-low NOx system that can achieve > 99.5% NOx conversion efficiency.

The model was calibrated …

Estimation Of Multi-Directional Ankle Impedance As A Function Of Lower Extremity Muscle Activation, Lauren Knop

Dissertations, Master's Theses and Master's Reports

The purpose of this research is to investigate the relationship between the mechanical impedance of the human ankle and the corresponding lower extremity muscle activity. Three experimental studies were performed to measure the ankle impedance about multiple degrees of freedom (DOF), while the ankle was subjected to different loading conditions and different levels of muscle activity. The first study determined the non-loaded ankle impedance in the sagittal, frontal, and transverse anatomical planes while the ankle was suspended above the ground. The subjects actively co-contracted their agonist and antagonistic muscles to various levels, measured using electromyography (EMG). An Artificial Neural Network …

Networked Microgrid Optimization And Energy Management, Robert S. Jane

Dissertations, Master's Theses and Master's Reports

Military vehicles possess attributes consistent with a microgrid, containing electrical energy generation, storage, government furnished equipment (GFE), and the ability to share these capabilities via interconnection. Many military vehicles have significant energy storage capacity to satisfy silent watch requirements, making them particularly well-suited to share their energy storage capabilities with stationary microgrids for more efficient energy management. Further, the energy generation capacity and the fuel consumption rate of the vehicles are comparable to standard diesel generators, for certain scenarios, the use of the vehicles could result in more efficient operation. Energy management of a microgrid is an open area of …

Magnetic Domain Structures In Fe-Ga Alloys, Matthew N. Tianen

Dissertations, Master's Theses and Master's Reports

Fe-Ga alloys, also referred to as Galfenol, have attracted great attention as new giant magnetostrictive materials for over fifteen years. They exhibit large magnetostriction, small hysteresis, good machinability, and high tensile strength, providing many advantages over other functional materials like magnetostrictive Terfenol-D, piezoelectric PZT, and magnetic shape memory Ni-Mn-Ga. In spite of the intense interest in Fe-Ga alloys, the domain phenomena that underlie their properties and functionalities are less known. Using the Bitter method, a systematic study of magnetic domain structures in Fe-Ga single crystals of different compositions and heat treatments has been performed. Our domain observation experiments reveal numerous …

A Smart Implantable Bone Fixation Plate Providing Actuation And Load Monitoring For Orthopedic Fracture Healing, Brad Nelson

Dissertations, Master's Theses and Master's Reports

Fracture non-union occurs in roughly 5-10% of all fracture cases, and current interventions are both time-consuming and costly. There is therefore significant incentive to develop new tools to improve fracture healing outcomes. Several studies have shown that low-magnitude, high-frequency (LMHF) mechanical loading can promote faster healing and reduce the risk of refracture in critical-size long bone fractures. This is typically done using whole-body vibration, which may result in undesirable systemic effects on the rest of the body. This work discusses an implantable piezoelectric fixation plate that can both apply LMHF loading directly to the fracture site using flexible scheduling and …

Acoustic Localization Techniques For Application In Near-Shore Arctic Environments, Miles B. Penhale

Dissertations, Master's Theses and Master's Reports

The Arctic environment has undergone significant change in recent years. Multi-year ice is no longer prevalent in the Arctic. Instead, Arctic ice melts during summer months and re-freezes each winter. First-year ice, in comparison to multi-year ice, is different in terms of its acoustic properties. Therefore, acoustic propagation models of the Arctic may no longer be valid. The open water in the Arctic for longer time periods during the year invites anthropogenic traffic such as civilian tourism, industrial shipping, natural resource exploration, and military exercises. It is important to understand sound propagation in the first-year ice environment, especially in near-shore …

Effect Of Development Of Scandium Trialuminide Precipitates On Corrosion And Mechanical Behavior In Aluminum-Magnesium Alloys, Carson Williams

Dissertations, Master's Theses and Master's Reports

Development of aluminum alloys has seen an increase in attention in recent years. The 5xxx series of Al-Mg alloys has the potential to provide strong, lightweight materials in various industry applications, however issues with strain formability and corrosion hinder the development of these alloys. The addition of Sc for developing Al₃Sc precipitates provides considerable precipitation strengthening as well as grain refinement characteristics that can help mitigate these issues. Alloys with varied Mg content were analyzed for heat treatment aging responses and precipitate formation, changes in mechanical behavior related to the Portevin-le Chatelier effect, and effects on intergranular corrosion …

Investigating Microalloying Elements To Accelerate Zirconium Trialuminide Precipitation In Aluminum Alloys, Philip D. Staublin

Dissertations, Master's Theses and Master's Reports

Precipitation of the L1₂-structured coherent Al₃Zr trialuminide phase in aluminum-zirconium alloys increases the alloy strength. Precipitation of a more refined dispersion of Al₃Zr can further increase the strength of these alloys. The addition of microalloying elements which bind to zirconium may accelerate the precipitation kinetics, allowing for nucleation of a greater number of precipitates and faster precipitate growth. Zirconium binding energies are computed for a wide range of elements, based on which the elements tin, antimony, and tellurium were selected for investigation. Ternary Al-Zr-X alloys (X = Sn, Sb, Te) were cast and heat …

Hydrologic Impacts And Trade-Offs Associated With Forest-Based Bioenergy Development Across The Americas, Azad Heidari

Dissertations, Master's Theses and Master's Reports

A simulation-based framework for studying hydrologic impacts and associated tradeoffs for existing and proposed biofuel projects in the US (poplar), Argentina (eucalyptus) and Mexico (oil palm) is developed. For each case study, a representative watershed is selected and a SWAT model is set up and calibrated for an improved simulation of hydrologic processes and plant growth cycles. Potential bioenergy scenarios are developed that represent various planting densities, harvest cycles, fertilization and irrigation rates, land cover types being converted, slope, and locations across the watershed.

Simulations indicate that growth and biomass production are significantly dependent on nitrogen availability, making fertilization a …

Online Learning Of The Spatial-Temporal Channel Variation In Underwater Acoustic Communication Networks, Wensheng Sun

Dissertations, Master's Theses and Master's Reports

Influenced by environmental conditions, underwater acoustic (UWA) communication channels exhibit spatial and temporal variations, posing significant challenges for UWA networking and applications. This dissertation develops statistical signal processing approaches to model and predict variations of the channel and relevant environmental factors. Firstly, extensive field experiments are conducted in the Great Lakes region. Three types of the freshwater river/lake acoustic channels are characterized in the aspects of statistical channel variations and sound propagation loss, including stationary, mobile and under-ice acoustic channels. Statistical data analysis shows that relative to oceanic channels, freshwater river/lake channels have larger temporal coherence, higher correlation among densely …

Design And Development Of Personal Protective Equipment Products To Reduce The Impacts Of Machete Injuries For Indigenous Ngäbe Subsistence Farmers In Bocas Del Toro, Panama, Micah Koller

Dissertations, Master's Theses and Master's Reports

Design and development of personal protective equipment products for workers using machetes (MPPE) is considered in the specific context of indigenous Ngäbe subsistence farmers in a small, rural community in Bocas del Toro, Panama where the author spent two years as a Peace Corps volunteer from 2017-2019. People in this community regularly suffer significant health and economic impacts due to accidents with machetes, which are essential tools in their farm work and daily lives. The history, criticisms, and recent frameworks related to product design and development in resource-poor markets is examined, and specific details of the problem of machete injuries …

3d Printing In Low Resource Healthcare Settings: Analysis Of Potential Implementations, Alenna Beroza

Dissertations, Master's Theses and Master's Reports

3D printing has gained significant momentum in the past ten years, and its unique advantages make it especially ideal for use in low resource healthcare settings, where many designs have already been successfully implemented. Yet, little has been studied on how 3D printing can be sustainably and functionally implemented in low resource healthcare systems as a manufacturing practice. In this report, three business models are proposed for this implementation: In-House Operator, Independent Operator, and Print Farm. These models were then tested over four months in Kisumu county, Kenya, at two workshops and seven public hospitals. I worked with local medical …

Crack Pattern Simulation Of Pressurized Borosilicate Glass Tube Under Pellet Impact Using Ale Method, Omkar Bhumkar

Dissertations, Master's Theses and Master's Reports

Transformer bushings are a common target for sniper attacks to cause power failure in large areas. Given the size, internal pressure and brittle nature of transformer bushing, pellet impact causes damage to surrounding components due to broken bushing pieces. To mitigate this, a project was initiated by United States Burau of Reclaimation to develop a safety mechanism. Finite Element Analysis is proposed to optimize and reduce cost of the design.

A simplified Finite Element model is created which consists of 0.22 caliber lead pellet impacting Pyrex 7740 borosilicate glass tube. Previous studies on the effect of the mesh pattern, size …

Degradable Zinc Material Characteristics And Its Influence On Biocompatibility In An In-Vivo Murine Model, Roger J. Guillory Ii

Dissertations, Master's Theses and Master's Reports

Biodegradable stents based on zinc have been under development since their introduction in 2013. While metallic zinc is highly ductile, it unfortunately lacks the mechanical strength required for arterial stents. This has led to the development of an abundance of novel zinc-based materials, with the aim of improving the mechanical strength without sacrificing too much ductility. Although these materials are intended to function and slowly degrade within an artery, most zinc-based materials have been developed without deep consideration for their biological effects.

The present work explores the biological effects elicited by zinc-based materials implanted within the arterial system. The biological …

Assessing Benthic Recovery In The Torch Lake Aoc, Anya Clare Leach

Dissertations, Master's Theses and Master's Reports

Torch Lake, located in Michigan’s Upper Peninsula, was a site of copper ore processing from the 1860s through the 1960s. During this time, various mining by-products were deposited into the lake and along its shoreline, including mine tailings and associated heavy metals contaminants (e.g., copper). It was anticipated that natural sediment deposition would cover and attenuate toxic sediments over time, but a comprehensive assessment of the benthos has not been performed since a baseline survey conducted in 1999 and 2000. This study was conducted in 2018 to evaluate the current benthic community status as well as sediment composition and metal …

Environmental Policy Assessment In The Ghanaian Gold Mining Industry: Insights From Stakeholders, Francis Tuokuu

Antioch University Dissertations & Theses

Environmental policy assessment has been recognized by critical stakeholders (e.g., governments, local communities, academics, environmental advocacy groups, and mining companies) as an effective way of identifying and dealing with the myriad of environmental problems confronting humanity, particularly those caused by mining activities. While the gold mining sector has contributed to the economies of countries in Sub-Saharan Africa since the introduction of structural adjustment programs (SAPs) in the 1980s by the Bretton Woods institutions (the World Bank and the International Monetary Fund; IMF), the sector has also contributed to environmental degradation including water pollution, land contaminations, and generally, human health concerns …

A Sustainable Prototype For Renewable Energy: Optimized Prime-Power Generator Solar Array Replacement, Nathan Thomsen, Torrey J. Wagner, Andrew J. Hoisington, Steven J. Schuldt

Faculty Publications

Remote locations such as disaster relief camps, isolated arctic communities, and military forward operating bases are disconnected from traditional power grids forcing them to rely on diesel generators with a total installed capacity of 10,000 MW worldwide. The generators require a constant resupply of fuel, resulting in increased operating costs, negative environmental impacts, and challenging fuel logistics. To enhance remote site sustainability, planners can develop stand-alone photovoltaic-battery systems to replace existing prime power generators. This paper presents the development of a novel cost-performance model capable of optimizing solar array and Li-ion battery storage size by generating tradeoffs between minimizing initial …

Real-Time Path Planning In Constrained, Uncertain Environments, Randall Christensen, Robert C. Leishman

Faculty Publications

A key enabler of autonomous vehicles is the ability to plan the path of the vehicle to accomplish mission objectives. To be robust to realistic environments, path planners must account for uncertainty in the trajectory of the vehicle as well as uncertainty in the location of obstacles. The uncertainty in the trajectory of the vehicle is a difficult quantity to estimate, and is influenced by coupling between the vehicle dynamics, guidance, navigation, and control system as well as any disturbances acting on the vehicle. Monte Carlo analysis is the conventional approach to determine vehicle dispersion, while accounting for the coupled …

Available Transfer Capability Enhancement With Facts Using Hybrid Pi-Pso, Abubakar Sadiq Ahmad, Sunusi Sani Adamu, Muhammad Buhari

Turkish Journal of Electrical Engineering and Computer Sciences

In deregulation, growth in electrical loads necessitates improving power delivery, while nondiscriminatory access to transmission grid is a requirement. Deregulation causes a significant rise in transactions, which requires adequate transfer capability to secure economic transactions. In sustainable power delivery, FACTS devices are deployed to enhance available transfer capability (ATC). However, the high investment cost of FACTS makes the problem formulation a multiobjective optimization: power transfer maximization and minimization of FACTS sizes. Furthermore, due to the complexity in optimizing the control variables of voltage source converter types of FACTS, often the solution results in local optima and high computational time. This …

Toxicity Prediction Of Small Drug Molecules Of Aryl Hydrocarbon Receptor Using Aproposed Ensemble Model, Vishan Kumar Gupta, Prashant Singh Rana

Turkish Journal of Electrical Engineering and Computer Sciences

Quantitative structure-activity relationships and quantitative structure?property relationships have proved their usefulness for predicting toxicities of drug molecules regarding their biological activities. In silico toxicity prediction techniques are essential for reducing testing on rodents (in vivo) and for a less time-consuming and more cost-efficient alternative for the identification of toxic effects at an early stage of drug development. The authors aim to build a prediction model for better assessment of toxicity to quickly and efficiently test whether certain chemical compounds have the potential to disrupt the processes in the human body that may adversely affect human health. Here, we have proposed …

Early Reliability Assessment Of Component-Based Software System Using Coloredpetri Net, Amir Hosseinzadeh Mokarram, Ayaz Isazadeh, Habib Izadkhah

Turkish Journal of Electrical Engineering and Computer Sciences

Assessment of reliability in the early stages of software development from architectural models is one of the major challenges that many studies have addressed in this field in the last decade. The main drawbacks of existing methods are the following: 1) considering equal impact for all parts of the software architecture on system reliability, and 2) inability to determine the contribution of each part of the software in the system failure. This paper introduces the extended version of the colored petri net as an underlying verifiable model to evaluate the reliability of a software system. The proposed model enhances reliability …

In-Field Failure Assessment Of Tractor Hydraulic System Operation Viapseudospectrum Of Acoustic Measurements, Saurabh Gupta, Mahdi Khosravy, Neeraj Gupta, Hemand Darbari

Turkish Journal of Electrical Engineering and Computer Sciences

Hydrological working conditions are critical indicators for the maintenance of tractor mechanical systems. This research presents a pseudospectrum approach to analyze the particle pollution level of the hydraulic filter in its aging process and thus on-time prediction and diagnosis of weak or faulty conditions. The practical experiments of pseudospectrum analysis are performed on oil filter sound records. For mobile application purposes, besides deployment of advanced audio recording equipment, three popular brands of cell phones are used. The soundtracks are recorded in different incremental stages of fluid contamination by pollutive particles until being choked based on the ISO4406 standard. The pseudospectrum …

Path-Oriented Random Testing Through Iterative Partitioning (Ip-Prt), Esmaeel Nikravan, Saeed Parsa

Turkish Journal of Electrical Engineering and Computer Sciences

Path-oriented random testing aims at generating a uniformly distributed sequence of test data from a program input domain space to traverse a desired execution path of the program. To this aim, this article proposes a new algorithm to refine a program inputs domain space from invalid subdomains not covering the path. The validity of the subdomains is checked by a constraint propagation method against the path constraints (PCs). The proposed algorithm uses a divide and conquer technique to iteratively split the inputs domain into subdomains and each time refutes those subdomains that are inconsistent with the PCs. The remaining shrunken …

Low-Cost Multimode Diode-Pumped Tm:Yag And Tm:Luag Lasers, Ersen Beyatli

Turkish Journal of Electrical Engineering and Computer Sciences

We report a continuous-wave operation of Tm:YAG and Tm:LuAG lasers pumped with a low-cost, multimode AlGaAs laser diode. First, the lifetime and the absorbance behavior of 5 mm, 6 % Tm$^{3+}$-doped YAG and LuAG crystals were thoroughly investigated. A low-cost multimode 3W laser diode at 781 nm was then used as a pump source for the Tm$^{3+}$-doped laser systems. Using three different output couplers, up to 636 mW of output power was obtained from Tm:YAG laser, with a slope efficiency of 29 % at 2017 nm. The maximum output power was 637 mW in the Tm:LuAG laser, with a slope …