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Graduate Theses, Dissertations, and Problem Reports (ETD)

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Transit Agencies Performance Assessment And Implications, Parisa Hajibabaee Jan 2020

Transit Agencies Performance Assessment And Implications, Parisa Hajibabaee

Graduate Theses, Dissertations, and Problem Reports (ETD)

Although most transit systems operate in small urban and rural areas in the United States, these systems have rarely received the same attention as their urban counterparts, both in terms of ensuring the efficiency and effectiveness of their operations and understanding the factors that affect their performance. This thesis's main goals are to assess the performance of rural and small urban public transit agencies and help them evaluate adopting a ridehailing program, thereby improving their performance. We applied operations research and decision-making tools to two public transit projects in small urban and rural areas. The first project focuses on three …


Developing A Biophilic City Through Natural Land Transformation Analysis And Geodesign: The Case Of Purbachal New Town, Bangladesh, Udday Shankur Datta Jan 2020

Developing A Biophilic City Through Natural Land Transformation Analysis And Geodesign: The Case Of Purbachal New Town, Bangladesh, Udday Shankur Datta

Graduate Theses, Dissertations, and Problem Reports (ETD)

Dhaka, the capital city of Bangladesh is one of the fastest-growing metropolitan regions in the world. To solve the ever-increasing need for housing and to reduce the pressure of the population from the capital city, the Purbachal satellite city was planned. It is the biggest planned township in Bangladesh with an area of over 25 square kilometers. Purbachal is situated at the confluence of the Shitalakhya and Balu rivers. Historically a low-lying wetland, Purbachal has gone through a rapid transformation in past decades. The water bodies around the area have been filled in to create new developable land. Through remote …


The Influence Of Spatial Variance On Rock Strength And Mechanism Of Failure, Danqing Gao Jan 2020

The Influence Of Spatial Variance On Rock Strength And Mechanism Of Failure, Danqing Gao

Graduate Theses, Dissertations, and Problem Reports (ETD)

The heterogeneity in the rock formation affects both rock behavior and the strength. The effect of heterogeneity is observed both at the laboratory scale and at the rockmass level. The mechanical properties of intact rock vary considerably at laboratory scale and often an average value is used for design purposes. Similarly, the values are arbitrarily scaled when used at rockmass level. In underground coal mines, the effect of variability of properties is often observed with the erratic roof failure events that occur throughout the mine. The approach often was to use the deterministic values from limited site data to estimate …


Estimating Refactoring Efforts For Architecture Technical Debt, Samir Deeb Jan 2020

Estimating Refactoring Efforts For Architecture Technical Debt, Samir Deeb

Graduate Theses, Dissertations, and Problem Reports (ETD)

Paying-off the Architectural Technical Debt by refactoring the flawed code is important to control the debt and to keep it as low as possible. Project Managers tend to delay paying off this debt because they face difficulties in comparing the cost of the refactoring against the benefits they gain. For these managers to decide whether to refactor or to postpone, they need to estimate the cost and the efforts required to conduct these refactoring activities as well as to decide which flaws have higher priority to be refactored among others.

Our research is based on a dataset used by other …


Environment Search Planning Subject To High Robot Localization Uncertainty, Jared Joseph Beard Jan 2020

Environment Search Planning Subject To High Robot Localization Uncertainty, Jared Joseph Beard

Graduate Theses, Dissertations, and Problem Reports (ETD)

As robots find applications in more complex roles, ranging from search and rescue to healthcare and services, they must be robust to greater levels of localization uncertainty and uncertainty about their environments. Without consideration for such uncertainties, robots will not be able to compensate accordingly, potentially leading to mission failure or injury to bystanders. This work addresses the task of searching a 2D area while reducing localization uncertainty. Wherein, the environment provides low uncertainty pose updates from beacons with a short range, covering only part of the environment. Otherwise the robot localizes using dead reckoning, relying on wheel encoder and …


An Examination To Pathways Powering Car Using Clean Energy, Marina Miranda Jan 2020

An Examination To Pathways Powering Car Using Clean Energy, Marina Miranda

Graduate Theses, Dissertations, and Problem Reports (ETD)

Traditional vehicles powered by internal combustion engines contribute significantly to increasing emissions of greenhouses gasses (GHG). There has been increasing interest in powering vehicles using green energy include using electricity produced by wind turbine and solar panel. The green electricity can be used to directly charge the Battery Electric Vehicles (BEV), or producing hydrogen as fuel for Fuel Cell Electric Vehicles (FCEV) by converting electrical energy to hydrogen (H2) through water electrolysis. The low energy density H2 produced can be stored on board as either compressed H2 or liquefied H2.

This research examines the …


Metaheuristics For The Generalized Quadratic Assignment Problem, Roseline Mostafa Jan 2020

Metaheuristics For The Generalized Quadratic Assignment Problem, Roseline Mostafa

Graduate Theses, Dissertations, and Problem Reports (ETD)

The generalized quadratic assignment problem (GQAP) is the task of assigning a set of facilities to a set of locations such that the sum of the assignment and transportation costs is minimized. The facilities may have different space requirements, and the locations may have varying space capacities. Also, multiple facilities may be assigned to each location such that space capacity is not exceeded. In this research, an application of the GQAP is presented for assigning a set of machines to a set of locations on the plant floor. Two meta-heuristics are proposed for solving the GQAP: tabu search (TS) and …


Analysis Of Factors Influencing The Stationarity Of Surface Electromyography Signals Measured In Non-Fatigued Shoulder Muscles, Hui Ci Jan 2020

Analysis Of Factors Influencing The Stationarity Of Surface Electromyography Signals Measured In Non-Fatigued Shoulder Muscles, Hui Ci

Graduate Theses, Dissertations, and Problem Reports (ETD)

A reduction in the % stationarity of surface electromyography (SEMG) signals with respect to the initial or fresh condition is used to predict localized muscle fatigue. However, factors other than muscle fatigue can also influence the stationarity of SEMG signals. This study was aimed at analyzing the effect of various work/task related factors on the stationarity of SEMG signals obtained from non-fatigued shoulder muscles. Twelve participants were recruited for data collection and each one performed 120 trials characterized by the combination of 2 shoulder angles (60° and 120°), 2 planes of exertions (sagittal and scapular), 3 force levels (0lb, 2.5lb, …


Sustainability-Based Expert System For Additive Manufacturing And Cnc Machining, Josage Chathura Pamuditha Perera Jan 2020

Sustainability-Based Expert System For Additive Manufacturing And Cnc Machining, Josage Chathura Pamuditha Perera

Graduate Theses, Dissertations, and Problem Reports (ETD)

The development of technologies which enable resource efficient production is of paramount importance for the continued advancement of the manufacturing industry. In order to ensure a sustainable and clean energy future, manufacturers should be able to contrast and validate existing manufacturing technologies on a sustainability basis. In the post COVID-19 era of enterprise management, the use of artificial intelligence to simulate human expert decision making abilities will open new doors to achieving heightened levels of productivity and efficiency. The introduction of innovative technologies such as CNC machining and 3D printing to production systems has redefined the manufacturing landscape in a …


Searching For Needles In The Cosmic Haystack, Thomas Ryan Devine Jan 2020

Searching For Needles In The Cosmic Haystack, Thomas Ryan Devine

Graduate Theses, Dissertations, and Problem Reports (ETD)

Searching for pulsar signals in radio astronomy data sets is a difficult task. The data sets are extremely large, approaching the petabyte scale, and are growing larger as instruments become more advanced. Big Data brings with it big challenges. Processing the data to identify candidate pulsar signals is computationally expensive and must utilize parallelism to be scalable. Labeling benchmarks for supervised classification is costly. To compound the problem, pulsar signals are very rare, e.g., only 0.05% of the instances in one data set represent pulsars. Furthermore, there are many different approaches to candidate classification with no consensus on a best …


In Vitro Assessment Of Deleterious Impacts Of Organomodified Nanoclays And Their Incinerated Byproducts On Human Cells, Andrew Philip White Jan 2020

In Vitro Assessment Of Deleterious Impacts Of Organomodified Nanoclays And Their Incinerated Byproducts On Human Cells, Andrew Philip White

Graduate Theses, Dissertations, and Problem Reports (ETD)

Organomodified nanoclays (ONCs: i.e., smectite clays with different organic coatings), act as nanofillers in applications ranging from automotive, to aerospace, and biomedical implementations. Because of their large utilization, ONC industry is projected to be a U.S. $3.3 billion industry by 2023. However, emerging studies showed that ONCs and ONC-nanocomposites could harbor health risks upon pulmonary exposure and along their life cycle, namely during synthesis, handling, use, manipulation, and disposal. Specifically, the potential for exposure and adverse effects on human health primarily includes release of dry particulate during handling, manipulation, release during use, and release during the end-of-life disposal or recycling …


Evaluation Of Control Strategies For Overhead Work Using Electromyography Of Rotator Cuff Muscles, Hossein Motabar Jan 2020

Evaluation Of Control Strategies For Overhead Work Using Electromyography Of Rotator Cuff Muscles, Hossein Motabar

Graduate Theses, Dissertations, and Problem Reports (ETD)

Work-related musculoskeletal disorders (MSDs) of shoulder have a significant impact on overall health and economics in the industrialized nations. Rotator cuff is the most frequently injured region in the shoulder complex. Overhead work is considered as one of the most predominant causes of rotator cuff injuries. The workers in construction, automotive, and aerospace industries are routinely exposed to overhead exertions. Elimination of overhead work is nearly impossible due to various task and technology constraints. Therefore, appropriate intervention strategies based on the engineering and administrative controls opt to be used to prevent the hazardous impact of overhead exertions. The objective of …


Next Generation Of Applications Of Metal-Organic Frameworks For Energy And Environmental Sustainability, Qian Liu Jan 2020

Next Generation Of Applications Of Metal-Organic Frameworks For Energy And Environmental Sustainability, Qian Liu

Graduate Theses, Dissertations, and Problem Reports (ETD)

My PhD work aimed at using Metal-organic frameworks (MOFs) for mitigating the environmental issues and energy crisis associated with anthropogenic activities. Specifically, we developed robust platforms and/ or systems using MOF as “scaffolds” to allow for model pollutant detection and CO2 sequestration and benign transformation respectively.

First, I detailed how photocatalytic properties of 2,5-furandicarbocylic acid (FDCA) in its alone and its MOF- integrated form (MIL-160) were used for the first time for the reduction of Ag+ at room conditions. Such photocatalytic activities could then be used in user-designed hybrids (i.e., Ag/MIL-160) to form sensorial platforms for prevalent phenol …


Review Of Established And Emergent Methods For The Production Of C4 Olefins, James Matthew Koval Jan 2020

Review Of Established And Emergent Methods For The Production Of C4 Olefins, James Matthew Koval

Graduate Theses, Dissertations, and Problem Reports (ETD)

Current production of C4 olefins is dominated by naphtha cracking and butane dehydrogenation, but significant research interest is developing in alternate feedstocks due to an abundance of inexpensive natural gas and bioethanol. The current C4 olefin production methods are costly, make use of already-depleted petroleum resources, and are often hazardous to workers, which forms the impetus for investigation into alternative methods and assessment of their viability as a future means of olefin production. Methods of natural gas conversion to higher order hydrocarbons are discussed, including Fischer-Tropsch synthesis and oxidative methane coupling, each of which could form the first …


Grainyhead-Like 2 Sensitizes Cells To Natural Killer Cell Cytotoxicity And Promotes The Interferon Response, Ian Philip Macfawn Jan 2020

Grainyhead-Like 2 Sensitizes Cells To Natural Killer Cell Cytotoxicity And Promotes The Interferon Response, Ian Philip Macfawn

Graduate Theses, Dissertations, and Problem Reports (ETD)

Our research determined that the epithelial master transcription factor Grainyhead-like 2 (GRHL2) promotes sensitivity to Natural Killer (NK) cell-mediated killing, and modulates the interferon I (IFN-I) response of epithelial cells. Immune surveillance by NK cells constitutes a major selective pressure for circulating tumor cells. Epithelial (GRHL2-expressing) cells exhibited significantly higher rates of NK conjugation, a crucial step in direct cell-mediated cytotoxicity. Mechanistically, GRHL2 upregulates expression of intercellular adhesion molecule 1 (ICAM-1), a cell surface molecule critical for NK to target cell synaptogenesis. GRHL2 epigenetically regulates gene expression, and we found that GRHL2 mutant proteins unable to interact with the epigenetic …


Trees, Fungi, Insects: How Host Plant Genetics Builds A Community, Sandra Jeanne Simon Jan 2020

Trees, Fungi, Insects: How Host Plant Genetics Builds A Community, Sandra Jeanne Simon

Graduate Theses, Dissertations, and Problem Reports (ETD)

Organisms, such as fungi and insects, can cause millions of acres of agricultural and forest damage, while others provide billions of dollars in ecological services such as education, aesthetic enjoyment, pollination, and gardening. Plant breeding and biotechnology can potentially help establish a balance between the proliferation of detrimental pests and attraction of beneficial insects. Variation in plant physiological and morphological characteristics are extremely important in the ability of host tissues to support many different types of organisms. When that variation is genetically heritable in a plant population, shifts in the underlying genes can have predictable consequences in structuring entire ecosystems. …


Breast Cancer Associated Muscle Fatigue: Novel Targets To Improve Survival And Quality Of Life, Hannah Elizabeth Wilson Jan 2020

Breast Cancer Associated Muscle Fatigue: Novel Targets To Improve Survival And Quality Of Life, Hannah Elizabeth Wilson

Graduate Theses, Dissertations, and Problem Reports (ETD)

Women diagnosed with breast cancer (BC) currently represent the largest group of cancer survivors in the United States, accounting for over 20% of those living after a cancer diagnosis. Most BC survivors report an unusual degree of fatigue, which can present prior to diagnosis and continue for many years after treatment cessation. Recent studies show that deficits in muscle function predict shorter survival in cancer, perhaps due to the fact that fatigue is known to reduce a patient’s tolerance to anti-cancer therapies. Therefore, improving muscle function in BC patients has the potential to improve both quality of life and survival …


Parametric Optimization Of Visible Wavelength Gold Lattice Geometries For Improved Plasmon-Enhanced Fluorescence Spectroscopy, Casey A. Norville Jan 2020

Parametric Optimization Of Visible Wavelength Gold Lattice Geometries For Improved Plasmon-Enhanced Fluorescence Spectroscopy, Casey A. Norville

Graduate Theses, Dissertations, and Problem Reports (ETD)

The exploitation of spectro-plasmonics will allow for innovations in optical instrumentation development and the realization of more efficient optical biodetection components. Biosensors have been shown to improve the overall quality of life through real-time detection of various antibody-antigen reactions, biomarkers, infectious diseases, pathogens, toxins, viruses, etc. has led to increased interest in the research and development of these devices. Further advancements in modern biosensor development will be realized through novel electrochemical, electromechanical, bioelectrical, and/or optical transduction methods aimed at reducing the size, cost, and limit of detection (LOD) of these sensor systems. One such method of optical transduction involves the …


Comparative Assessment Of Different Ultra-Low Nox Measurement Instruments For Heavy-Duty Diesel Engines, Diego Bernabe Mejia Jan 2020

Comparative Assessment Of Different Ultra-Low Nox Measurement Instruments For Heavy-Duty Diesel Engines, Diego Bernabe Mejia

Graduate Theses, Dissertations, and Problem Reports (ETD)

Constant Volume Sampling (CVS) systems are an approved method for emission testing as stated in CFR Title 40 Part 1065 Engine Emission Testing Program. For future near zero emission vehicles, the emission measurement equipment must verify the results with the same accuracy as the limits in the past. The most critical values are the limitations for THC, NOx and particulate matter.

The objective of this study was aimed at identifying challenges associated with measuring system-out emissions at proposed ultra-low NOx (ULNOx) levels - 0.02 (g/bhp-hr) and system robustness. The study compared a variety of existing instrument …


Doping With Rare Earth Elements And Resultant Nano-Inclusions On The Electrical And Thermal Properties Of The Mis-Fit Layered Thermoelectric Oxide, Geoffroy Gauneau Jan 2020

Doping With Rare Earth Elements And Resultant Nano-Inclusions On The Electrical And Thermal Properties Of The Mis-Fit Layered Thermoelectric Oxide, Geoffroy Gauneau

Graduate Theses, Dissertations, and Problem Reports (ETD)

Thermoelectric generators produce electricity by directly converting temperature differences into electrical energy through Seebeck effect. Thermoelectric generators possess many unique features, such as having no moving part and being very reliable with a relatively long lifespan once built. They are solid-state waste heat harvesters. With various waste heat available throughout many industries, thermoelectric generators could offer economically competitive renewable energy. The current state of the art thermoelectric materials includes materials with relatively toxic elements and must work under vacuum, making them quite expensive to produce. Among the various thermoelectric materials, ceramic oxides have been proved to be more chemically stable …


Process Development Of Shale Gas Assisted Lignin And Biomass Reforming Through Novel Reaction Pathway And Catalyst Design To Produce Hydrogen Rich Syngas For Fuels And Value Added Chemicals, Amoolya D. Lalsare Jan 2020

Process Development Of Shale Gas Assisted Lignin And Biomass Reforming Through Novel Reaction Pathway And Catalyst Design To Produce Hydrogen Rich Syngas For Fuels And Value Added Chemicals, Amoolya D. Lalsare

Graduate Theses, Dissertations, and Problem Reports (ETD)

Novel biomass reforming strategy through synergistic co-processing with flare gas (methane and carbon dioxide) was developed at West Virginia University. Hardwood biomass comprised of lignin, hemicellulose, and cellulose is abundant in the US and potentially a sustainable source of hydrogen through extensive reforming and gasification. Ever-increasing shale gas production in the US occasionally leads to flaring owing to stranded production across the US. Achieving biomass co-processing with natural gas about to be flared in such stranded shale plays is the underlying motivation here. A novel reaction pathway was discovered wherein methane and carbon dioxide assisted reforming of biomass could be …


Speech Mode Classification Using The Fusion Of Cnns And Lstm Networks, Pratyusha Chowdary Vakkantula Jan 2020

Speech Mode Classification Using The Fusion Of Cnns And Lstm Networks, Pratyusha Chowdary Vakkantula

Graduate Theses, Dissertations, and Problem Reports (ETD)

Speech mode classification is an area that has not been as widely explored in the field of sound classification as others such as environmental sounds, music genre, and speaker identification. But what is speech mode? While mode is defined as the way or the manner in which something occurs or is expressed or done, speech mode is defined as the style in which the speech is delivered by a person.

There are some reports on speech mode classification using conventional methods, such as whispering and talking using a normal phonetic sound. However, to the best of our knowledge, deep learning-based …


Application Of Decline Curve Analysis To Unconventional Reservoir, Ahmed Wasel Alqattan Jan 2020

Application Of Decline Curve Analysis To Unconventional Reservoir, Ahmed Wasel Alqattan

Graduate Theses, Dissertations, and Problem Reports (ETD)

The oil and gas industry has been dealing with the unconventional reservoirs for about only two decades. Consequently, many challenges remain in evaluating the unconventional reservoirs. A few of these obstacles are the absence of the adequate production history, understanding the fluid flow regime after hydraulic fracturing, and estimating the drainage volume of the reservoir. One of the essential elements for evaluation of the oil and reservoir is to estimate the production rates over time in order to investigate the economic potential of the project.

Decline Curve Analysis (DCA) is most common the methodology for predicting the production rates over …


A Machine Learning Approach To Estimate The Annihilation Photon Interactions Inside The Scintillator Of A Pet Scanner, Sai Akhil Bharthavarapu Jan 2020

A Machine Learning Approach To Estimate The Annihilation Photon Interactions Inside The Scintillator Of A Pet Scanner, Sai Akhil Bharthavarapu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Biochemical processes are chemical processes that occur in living organisms. They can be studied with nuclear medicine through the help of radioactive tracers. Based on the radioisotope used, the photons that are emitted from the body tissue are either detected by single-photon emission computed tomography (SPECT) or by positron emission tomography (PET) scanners. SPECT uses gamma rays as tracer but gives a weaker contrast and spatial resolution compared to a PET scanner which uses positrons as tracer. PET scans show the metabolic changes occurring at the cellular level in an organ or a tissue. This detection is important because diseases …


Design, Modeling And Optimization Of Reciprocating Tubular Permanent Magnet Linear Generators For Free Piston Engine Applications, Jayaram Subramanian Jan 2020

Design, Modeling And Optimization Of Reciprocating Tubular Permanent Magnet Linear Generators For Free Piston Engine Applications, Jayaram Subramanian

Graduate Theses, Dissertations, and Problem Reports (ETD)

Permanent Magnet Linear Generators (PMLG) are electric generators which convert the linear motion into electricity. One of the applications of the PMLG system is with free piston engines. Here, the piston is moved by the expander using an internal combustion engine or a Stirling engine. Other applications of the PMLG are wave energy conversion, micro energy harvesters, and supercritical CO2 expander systems. The most common technology of the electric generators is a rotary electric generator. The current technology of the engine-generators (GENSET) is of a rotary type which uses a crankshaft to convert the linear motion to rotary motion …


Effect Of Particle Concentration, Sealing Condition And Breathing Rate On Total Inward Leakage For N95 Filtering Facepiece Respirators, Taoreed T. Lawal Jan 2020

Effect Of Particle Concentration, Sealing Condition And Breathing Rate On Total Inward Leakage For N95 Filtering Facepiece Respirators, Taoreed T. Lawal

Graduate Theses, Dissertations, and Problem Reports (ETD)

Several researchers have considered the relationship between total inward leakage (TIL) and other parameters such as sealing condition, particle concentration, type of particulate material breathing parameters, etc., however, there is dearth of information on the effects of varying particle concentration on the penetration efficiency of filtering facepiece respirators (FFRs), hence, this study aims to study the effect of varying NaCl particle concentration, sealing condition and breathing rate on the TIL as a result of the filtering efficiency of the filters.

To achieve this, we followed the sampling procedure used by He et al., 2014. Four different sealing conditions (SCs) namely; …


Solutions To Some Mine Subsidence Research Challenges, Jian Yang Jan 2020

Solutions To Some Mine Subsidence Research Challenges, Jian Yang

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of this work is to address three challenging topics, (1) effects of overburden key strata on subsurface subsidence; (2) effects of longwall subsidence on interstate highways and highway bridges; and (3) effects of dewatering mine water on surface subsidence over inactive room-and-pillar mines, in mine subsidence and to continue improvement of mine safety and health by reducing mine-subsidence related hazards.

Surface and subsurface subsidence events induced by underground mining activities are often capable of causing significant disturbances not only to surface structures, but also to subsurface structures. In this work, models and techniques to study three challenging topics …


Protein/Peptide Characterization Using Mass Spectrometry And Molecular Dynamics Simulations, Ahmad Kiani Karanji Jan 2020

Protein/Peptide Characterization Using Mass Spectrometry And Molecular Dynamics Simulations, Ahmad Kiani Karanji

Graduate Theses, Dissertations, and Problem Reports (ETD)

Mass spectrometry (MS) based-techniques and molecular dynamics (MD) simulations have been used to characterize protein/peptide structure as well as their interactions with lipid vesicles and detergents. Chapter 1 introduces an introduction to the concepts and tools that were used in this work. In Chapter 2, the dominant gas-phase conformer of [M+3H]3+ ions of the model peptide Acetyl-PSSSSKSSSSKSSSSKSSSSK are examined with ion mobility spectrometry (IMS), gas-phase hydrogen deuterium exchange (HDX), and mass spectrometry (MS) techniques. This section furthers the development of a protein structural prediction tool by providing information about gas-phase ion conformers of two model peptides having different solution conformational …


Palmprint Gender Classification Using Deep Learning Methods, Minou Khayami Jan 2020

Palmprint Gender Classification Using Deep Learning Methods, Minou Khayami

Graduate Theses, Dissertations, and Problem Reports (ETD)

Gender identification is an important technique that can improve the performance of authentication systems by reducing searching space and speeding up the matching process. Several biometric traits have been used to ascertain human gender. Among them, the human palmprint possesses several discriminating features such as principal-lines, wrinkles, ridges, and minutiae features and that offer cues for gender identification. The goal of this work is to develop novel deep-learning techniques to determine gender from palmprint images. PolyU and CASIA palmprint databases with 90,000 and 5502 images respectively were used for training and testing purposes in this research. After ROI extraction and …


Measured And Modeled Performance Of A Spring Dominant Free Piston Engine Generator, Ramanjaneya Mehar Baba Bade Jan 2020

Measured And Modeled Performance Of A Spring Dominant Free Piston Engine Generator, Ramanjaneya Mehar Baba Bade

Graduate Theses, Dissertations, and Problem Reports (ETD)

Free Piston Engine Generators (FPEG) directly convert the reciprocating piston motion into electricity by using a linear alternator. Unlike conventional engines with piston motion restricted by a crankshaft mechanism, the FPEG piston motion is constrained by the energy available in the system. When stiff springs are considered in the design, the FPEG system attains high frequency with high power and efficiency. The main objective of this research was to model stiff spring-assisted FPEG system dynamics and performance accurately, and to apply the modeling results to the development of a 1kW, spark ignited, natural gas fueled, FPEG experimental prototype. The experimental …