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Full-Text Articles in Engineering

Cavitation And Heat Transfer Over Micro Pin Fins, Arash Nayebzadeh Jan 2019

Cavitation And Heat Transfer Over Micro Pin Fins, Arash Nayebzadeh

Electronic Theses and Dissertations

With the dramatic increase in the usage of compact yet more powerful electronic devices, advanced cooling technologies are required to maintain delicate electronic components below their maximum allowable temperatures and prevent them from failure. One solution is to use innovative pin finned heat sinks. This research is centered on the evaluation of hydrodynamic cavitation properties downstream pin fins and extended toward single-phase heat transfer enhancement of array of pin fins in microchannel. In this work, transparent micro-devices capable of local wall temperature measurements were micro fabricated and tested. Various experimental methods, numerical modeling and advanced data processing techniques are presented. …


Interfacial Behavior In Polymer Derived Ceramics And Salt Water Purification Via 2d Mos2, Hao Li Jan 2019

Interfacial Behavior In Polymer Derived Ceramics And Salt Water Purification Via 2d Mos2, Hao Li

Electronic Theses and Dissertations

In the present dissertation, the behavior of the internal potential barrier in a polymer-derived amorphous SiAlCN ceramic was studied by measuring its complex impedance spectra at various dc bias as well as different testing and annealing temperatures. The complex impedance spectra of the polymer-derived a-SiAlCN were measured under various dc bias voltages in a temperature range between 50 and 150°C, as well as different annealing temperatures (1100-1400 °C). All spectra, regardless of temperature and bias, consist of two semi-circular arcs, corresponding to the free-carbon phase and the interface, respectively. The impedance of the free-carbon phase is independent of the bias, …


Disinfection By-Product Formation Potential Assessment For Central Florida Groundwater Supplies, Tulsi Shukla Jan 2019

Disinfection By-Product Formation Potential Assessment For Central Florida Groundwater Supplies, Tulsi Shukla

Electronic Theses and Dissertations

Disinfection of potable water supplies is a primary requirement of the United States' Environmental Protection Agency's (USEPA's) Safe Drinking Water Act. The use of chlorine as a disinfectant is widely accepted by water purveyors due to its effectiveness and low cost. However, chlorine reacts with natural organic matter present in water supplies to form suspected carcinogenic disinfection by-products (DBPs). In this work, the formation of the regulated chlorinated by-products total trihalomethanes (TTHMs) and haloacetic acids (HAA5) for eleven Central Florida wells has been investigated. Fluorescence, UV-254, dissolved organic carbon (DOC), specific UV absorbance (SUVA), chlorine decay, and TTHM and HAA5 …


Detection Of Ddh In Infants And Children Using Audible Acoustics, Tanvir Hassan Jan 2019

Detection Of Ddh In Infants And Children Using Audible Acoustics, Tanvir Hassan

Electronic Theses and Dissertations

Detection of developmental dysplasia of the hip (DDH) in infants and children is important as it leads to permanent hip instability. Current methods for detecting DDH, such as ultrasound and x-rays, are relatively expensive and need qualified medical personnel to administer the test. Furthermore, x-ray ionizing radiation can have potential harmful effects. In the current study, an acoustic non-invasive and simple approach was investigated for detection of DDH. Different benchtop simplified models and pig models were constructed and tested. Models were stimulated with band-limited white acoustic noise (10-2500 Hz) and the response of the models was measured. The power spectrum …


Basic Turbo Roundabouts As An Alternative To Conventional Double-Lane Roundabouts: Operational Performance Evaluation, Zuhair Elhassy Jan 2019

Basic Turbo Roundabouts As An Alternative To Conventional Double-Lane Roundabouts: Operational Performance Evaluation, Zuhair Elhassy

Electronic Theses and Dissertations

Conventional roundabouts have been prevalent worldwide since the emergence of modern roundabouts in 1966. An innovative design of multilane roundabouts known as turbo roundabouts, however, has been recently introduced as an alternative to conventional multilane roundabouts. Due to several reasons, there has been no general consensus on the operational performance of turbo roundabouts throughout the world. Nationwide, turbo roundabouts have yet to be part of roadway systems, but there is an ongoing project expected to be finished in early 2020. Therefore, this dissertation aims to evaluate the operational performance of a widespread variant of turbo roundabouts, namely basic turbo roundabouts, …


Fundamental Properties Of Metallic Nanolasers, William Hayenga Jan 2019

Fundamental Properties Of Metallic Nanolasers, William Hayenga

Electronic Theses and Dissertations

The last two decades have witnessed tremendous advancements in the area of nanophotonics and plasmonics, which has helped propel the development of integrated photonic sources. Of central importance to such circuits is compact, scalable, low threshold, and efficient coherent sources that can be driven at high modulation frequencies. In this regard, metallic nanolasers offer a unique platform. Their introduction has enabled confinement of light at a subwavelength scale and the ultra-small size of the modes afforded by these structures allows for cavity enhancing effects that can help facilitate thresholdless lasing and large direct modulation bandwidths. In this report, I present …


Processing Of Advanced Infrared Materials, Daniel Mcgill Jan 2019

Processing Of Advanced Infrared Materials, Daniel Mcgill

Electronic Theses and Dissertations

Infrared transparent glassy and crystalline materials often have unique and complex processing requirements but are an important class of materials for such applications as optical windows, lenses, waveplates, polarizers and beam splitters. This thesis investigates two specific materials, one amorphous and one crystalline, that are candidates for use in the short and midwave-infrared and mid and longwave infrared, respectively. It is demonstrated that an innovative uniaxial sintering process, which uses a sacrificial pressure-transmitting medium, can be used to fully densify a 70TeO2-20WO3-10La2O3 (TWL) glass powder. The characteristics of the sintered TWL glass is compared to that of a parent glass …


Modeling And Study Of Thermal Effects On Battery Pack Using Phase Change Materials, Umang Selokar Jan 2019

Modeling And Study Of Thermal Effects On Battery Pack Using Phase Change Materials, Umang Selokar

Electronic Theses and Dissertations

The scope of the current research is to reduce the temperature distribution area in Li-ion cell and the battery pack with respect to time in battery design, using CFD technology (Computational Fluid Dynamics) in ANSYS fluent. A 3D model was design in CAD software (CATIA) and analyzed in ANSYS fluent to study the thermal behavior of the designed battery pack. An analytical thermal model was generated to evaluate the heat generation rate passing throughout the battery pack. The battery pack were analyzed and simulated on two different designs. One battery design is modeled with and without insulation (superwool EST compression …


A Study Of The Effect Of Heat Treatment On 3d Printed Pla Impact Strength, Suresh Thota Jan 2019

A Study Of The Effect Of Heat Treatment On 3d Printed Pla Impact Strength, Suresh Thota

Electronic Theses and Dissertations

Environmental conditions have a significant effect on the mechanical properties of various materials. Environmental parameters such as temperature and humidity have a major impact on mechanical properties of materials such as compressive strength, tensile strength, bending strength and impact strength. The purpose of this research is to study how temperature and humidity affect the impact strength of 3D printed PLA plastic. Impact strength is the ability of a material to absorb energy subjected to an impact load by a pendulum. In this research, 3D printing was employed to produce PLA specimens which were later used for different experimental testings. For …


Classification Of North Africa For Use As An Extended Pseudo Invariant Calibration Sites (Epics) For Radiometric Calibration And Stability Monitoring Of Optical Satellite Sensors, Mahesh Shrestha Jan 2019

Classification Of North Africa For Use As An Extended Pseudo Invariant Calibration Sites (Epics) For Radiometric Calibration And Stability Monitoring Of Optical Satellite Sensors, Mahesh Shrestha

Electronic Theses and Dissertations

An increasing number of Earth-observing satellite sensors are being launched to meet the insatiable demand for timely and accurate data to help the understanding of the Earth’s complex systems and to monitor significant changes to them. The quality of data recorded by these sensors is a primary concern, as it critically depends on accurate radiometric calibration for each sensor. Pseudo Invariant Calibration Sites (PICS) have been extensively used for radiometric calibration and temporal stability monitoring of optical satellite sensors. Due to limited knowledge about the radiometric stability of North Africa, only a limited number of sites in the region are …


An Initial Exploration Of The 2005 Iowa Rural Interstate Speed Limit Increase Using Linear Regression, Thomas Ryan Cook Jan 2019

An Initial Exploration Of The 2005 Iowa Rural Interstate Speed Limit Increase Using Linear Regression, Thomas Ryan Cook

Electronic Theses and Dissertations

Speed limit increases, particularly on interstates have been studied and researched many times over the course of the last 50 years in the United States. These research efforts began after the implementation of the National Maximum Speed Law (NMSL), which reduced all speed limits to a maximum of 55-mph. In the years that followed, this restriction was relaxed to 65-mph with the Surface Transportation and Uniform Relocation Assistance Act (STURAA) and ultimately repealed later by the National Highway System Designation Act (NHSDA). Since the repeal, states reacted in myriad of ways and many studies documented the changes of those reactions. …


Machine Learning For Load Profile Data Analytics And Short-Term Load Forecasting, Md. Rashedul Haq Jan 2019

Machine Learning For Load Profile Data Analytics And Short-Term Load Forecasting, Md. Rashedul Haq

Electronic Theses and Dissertations

Short-term load forecasting (STLF) is a key issue for the operation and dispatch of day ahead energy market. It is a prerequisite for the economic operation of power systems and the basis of dispatching and making startup-shutdown plans, which plays a key role in the automatic control of power systems. Accurate power load forecasting not only help users choose a more appropriate electricity consumption scheme and reduces a lot of electric cost expenditure but also is conducive to optimizing the resources of power systems. This advantage helps while improving equipment utilization for reducing the production cost and improving the economic …


Methods For Earth-Observing Satellite Surface Reflectance Validation, Moe Talal Badawi Jan 2019

Methods For Earth-Observing Satellite Surface Reflectance Validation, Moe Talal Badawi

Electronic Theses and Dissertations

In this study an initial validation of the Landsat 8 (L8) Operational Land Imager (OLI) Surface Reflectance (SR) product was performed. The OLI SR product is derived from the L8 Top-of-Atmosphere product via the Landsat Surface Reflectance Code (LaSRC) software and generated by the U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center. The goal of this study is to develop and evaluate proper validation methodology for the OLI L2 SR product. Validation was performed using near-simultaneous ground truth SR measurements during Landsat 8 overpasses at 13 sites located in the U.S., Brazil, Chile and France. The ground …


Development Of A Neural Network-Based Object Detection For Multirotor Target Tracking, Spencer Harwood Jan 2019

Development Of A Neural Network-Based Object Detection For Multirotor Target Tracking, Spencer Harwood

Electronic Theses and Dissertations

Unmanned aerial vehicles (UAVs) have, for the past few decades, seen an increased popularity in industry and research centres. Despite this intense utilization by both markets there exists an active demand for the development of autonomous guidance, navigation, and control strategies. One need relates to the achievement of a high level of autonomy to identify and track a target object. An elective technique for this set of tasks is neural networks. In the development and study of these networks there is a distinct lack of substantive validation techniques to qualify network performances when implemented in a multirotor UAV. This thesis …


Energy Optimization And Coordination Frameworks For Smart Homes Considering Incentives From Discomfort And Market Analysis, Priti Paudyal Jan 2019

Energy Optimization And Coordination Frameworks For Smart Homes Considering Incentives From Discomfort And Market Analysis, Priti Paudyal

Electronic Theses and Dissertations

The electricity demand is increasing with the growing use of electricity-based appliances in today’s world. The residential sector’s electricity consumption share is also increasing. Demand response (DR) is a typical way to schedule consumers’ energy consumption and help utility to reduce the peak load demand. Residential demand management can contribute to reduce peak electric demand, decrease electricity costs, and maintain grid reliability. Though the demand management has benefits to the utility and the consumers, controlling the consumers electricity consumption provides inconvenience to the consumers. The challenge here is to properly address the customers’ inconvenience to encourage them to participate and …


Escherichia Coli Removal From Stormwater Using Steel Chips Filter, Peng Dai Jan 2019

Escherichia Coli Removal From Stormwater Using Steel Chips Filter, Peng Dai

Electronic Theses and Dissertations

Media filtration has received increasing attention as an effective technology that can facilitate the removal of particles and dissolved pollutions in the stormwater. However, most traditional media filtration systems are generally ineffective in removing bacteria, causing pollution of groundwater and receiving surface water. In this study, recycled steel chips were evaluated as low-cost filter materials for bacterial removal from stormwater. Laboratory column experiments were conducted to evaluate the impact of steel chips particle size, flow rate, initial E.coli concentration, pH, natural organic matter (NOM), steady and intermittent flow on E.coli removal. The results showed that E.coli removal decreased from 99.4% …


A Study Of Several Applications Of Parallel Computing In The Sciences Using Petsc, Nicholas Stegmeier Jan 2019

A Study Of Several Applications Of Parallel Computing In The Sciences Using Petsc, Nicholas Stegmeier

Electronic Theses and Dissertations

The importance of computing in the natural sciences continues to grow as scientists strive to analyze complex phenomena. The dynamics of turbulence, astrophysics simulations, and climate change are just a few examples where computing is critical. These problems are computationally intractable on all computing platforms except supercomputers, necessitating the continued development of efficient algorithms and methodologies in parallel computing. This thesis investigates the use of parallel computing and mathematical modeling in the natural sciences through several applications, namely computational fluid dynamics for impinging jets in mechanical engineering, simulation of biofilms in an aqueous environment in mathematical biology, and the solution …


Quantifying The Performance Of The Protodune Single Phase Neutrino Detector Using Computational Fluid Dynamics, Dillon Pedersen Jan 2019

Quantifying The Performance Of The Protodune Single Phase Neutrino Detector Using Computational Fluid Dynamics, Dillon Pedersen

Electronic Theses and Dissertations

The goal of this research is to provide scientifically-valid computationally generated data of the flow, thermal, and impurity data of the ProtoDUNE single phase detector. Results are compared and validated against an actual detector that is currently being utilized to collect temperature and impurity data. This research will investigate the flows inside these detection chambers using computational fluid dynamics to find approximate solutions to the governing equations of fluid mechanics. Impurity and flow data will allow researchers to determine if results collected are being obstructed by high levels of impurity. Novel approaches have been developed to strike a balance between …


The Effects Of 3d Printing Parameters And Surface Treatments On Convective Heat Transfer Performance, Lucas N. Pereira Jan 2019

The Effects Of 3d Printing Parameters And Surface Treatments On Convective Heat Transfer Performance, Lucas N. Pereira

Electronic Theses and Dissertations

Additive manufacturing technology and applications have quickly expanded in many industries over the last five years. As additive manufacturing is studied and refined, improvements in resolution and strength have helped propel further growth of the industry. This study focuses on an additive manufacturing technology called fused filament fabrication (FFF). FFF involves the extrusion and layer-by-layer deposition of a molten thermoplastic material to create the desired part. One potential new application of fused filament fabrication is the manufacture of heat exchangers and heat sinks. This study focuses on developing baseline experimental data related to convective heat transfer coefficients over surfaces of …


Pilot Scale Evaluation Of E. Coli Filtration Removal From Stormwater Using Recycled Steel, Jason Neville Jan 2019

Pilot Scale Evaluation Of E. Coli Filtration Removal From Stormwater Using Recycled Steel, Jason Neville

Electronic Theses and Dissertations

Microbial pathogens are considered one of the most important pollutants in regards to surface waters such as coastal waters, rivers and urban estuaries. Escherichia Coli (E. coli) is a bacterial microorganism found in the guts of humans and some animals that if ingested can cause diarrhea, severe stomach cramps, and vomiting. E. coli carried by stormwater runoff can deteriorate water quality of receiving bodies of water. It is necessary to develop technologies to remove E. coli from stormwater runoff to protect surface waters and public health. The use of steel byproducts as an adsorption technology is an emerging stormwater treatment …


Natural Sunlight Photodegradation Of Halogenated Disinfection Byproducts In Water, Ibrahim Abusallout Jan 2019

Natural Sunlight Photodegradation Of Halogenated Disinfection Byproducts In Water, Ibrahim Abusallout

Electronic Theses and Dissertations

Disinfection byproducts (DBPs) presence in wastewater effluents and receiving waters may impact the quality of drinking water during water reuse practices. Natural solar photolysis is one of the biogeochemical processes that may lead to decreased DBPs concentrations in water. The purpose of this dissertation is to determine the fate of chlorinated, brominated and iodinated DBPs in surface water by natural sunlight photolysis and investigate the use of solar-based advanced oxidation processes (AOPs) for removal of DBPs in water. Total organic halogen (TOX) was used to measure total chlorinated- (TOCl), brominated- (TOBr) and iodinated-DBPs (TOI) in water. The first objective was …


Mechanical Properties Of 3d Printed Acrylonitrile Styrene Acrylate, William Cahyadi Jan 2019

Mechanical Properties Of 3d Printed Acrylonitrile Styrene Acrylate, William Cahyadi

Electronic Theses and Dissertations

Several studies have been conducted on FDM 3d printed materials such as PLA (Polylactic Acid) and ABS (Acrylonitrile Butadiene Styrene), however, not for ASA (Acrylonitrile Styrene Acrylate). The use of ASA has been increasing due to its resistance to UV, heat, and some chemicals. The resistance to UV prevents the material from degrading its material properties in common outdoor conditions, whereas resistance to heat and oil prevents the material from discoloration. This combination of effects allows designers to use ASA in outdoor applications, however, material properties for ASA in the FDM 3d printing manufacturing process are not well defined. It …


Repairable Moment-Resisting Steel Buildings, Heath William Pederson Jan 2019

Repairable Moment-Resisting Steel Buildings, Heath William Pederson

Electronic Theses and Dissertations

Current seismic design codes ensure life safety for buildings, but structural members may significantly yield or even fail under strong earthquakes. A new design approach is to implement connections that localize the yielding and failure to fuses. A more sophisticated approach is to be able to replace the fuses after the event. The present study was carried out to develop repairable moment-resisting (MR) connections for steel buildings and to investigate their seismic performance through nonlinear finite element analyses (FEA). Two details were proposed using buckling restrained fuses (BRFs) and buckling restrained reinforcement (BRR). Test data was collected from the literature …


Geothermal Resource Assessment Of Mississippi, Adam Blake Goodwin Jan 2019

Geothermal Resource Assessment Of Mississippi, Adam Blake Goodwin

Electronic Theses and Dissertations

Geothermal energy is exploited through the process of using hot water or steam extracted from reservoirs of geothermal heat in Earth's crust which is derived from the upward convection and conduction of heat from Earth’s mantle and core. This energy can be harnessed to power geothermal heat pumps, heat water, or to generate electricity. Previous geothermal assessments of Mississippi have been locally focused, either in the southern Mississippi River flood plains or in eastern north central Mississippi at an active lignite coal mine. The focus of this project was to calculate and map heat flow estimates within the entire state …


A Numerical Study Of Granular Dam-Break Flows, Nuttita Pophet Jan 2019

A Numerical Study Of Granular Dam-Break Flows, Nuttita Pophet

Electronic Theses and Dissertations

Granular flows are mass movements of mixtures of solid particles and interstitial fluid. Examples include landslides, debris flows and tailings dam-break flows. These types of flows are often catastrophic events, and cover a wide range of phenomena of interest to both scientists and engineers. The mechanical properties of granular materials and the hydraulic behavior of the flows originate from solid and fluid phases, their distribution and interaction. Understanding the behavior of these types of flows and developing reliable predictive models are important.


Mac-Phy Frameworks For Lte And Wifi Networks' Coexistence Over The Unlicensed Band, Hadi Ahmad Kasasbeh Jan 2019

Mac-Phy Frameworks For Lte And Wifi Networks' Coexistence Over The Unlicensed Band, Hadi Ahmad Kasasbeh

Electronic Theses and Dissertations

The main focus of this dissertation is to address these issues and to analyze the interactions between LTE and WiFi coexisting on the unlicensed spectrum. This can be done by providing some improvements in the first two communication layers in both technologies. Regarding the physical (PHY) layer, efficient spectrum sensing and data fusion techniques that consider correlated spectrum sensing readings at the LTE/WiFi users (sensors) are needed. Failure to consider such correlation has been a major shortcoming of the literature. This resulted in poorly performing spectrum sensing systems if such correlation is not considered in correlated-measurements environments.


Dynamic Code Selection Method For Content Transfer In Deep Space Network, Rojina Adhikary Jan 2019

Dynamic Code Selection Method For Content Transfer In Deep Space Network, Rojina Adhikary

Electronic Theses and Dissertations

Space communications feature large round-trip time delays (for example, between 6.5 and 44 minutes for Mars to Earth and return, depending on the actual distance between the two planets) and highly variable data error rates, for example, bit error rate (BER) of 10−5 is very comand even higher BERs on the order of 10−1 is observed in the deep- space environment. We develop a new content transfer protocol based on RaptorQ codes and turbo codes together with a real-time channel prediction model to maximize file transfer from space vehicles to the Earth stations. While turbo codes are used to correct …


Techno-Economic And Sustainability Study Of Pv Inverter Controllers In Distribution Networks For Voltage Regulation, Kapil Duwadi Jan 2019

Techno-Economic And Sustainability Study Of Pv Inverter Controllers In Distribution Networks For Voltage Regulation, Kapil Duwadi

Electronic Theses and Dissertations

Increasing distributed solar installations in low voltage distribution grids tend to increase the feeder voltage. The rise in voltage is only acceptable to a certain limit, and control strategies are required to keep voltage within defined bounds for equipment safety and system reliability. PV inverter control strategies are cost-effective methods to prevent overvoltage. Different inverter control strategies have different impacts on their techno-economic performance, ultimately affecting their sustainability. An evaluation framework for long-term techno-economic and sustainability analysis of overvoltage prevention methods in PV-rich LV networks is proposed to decide suitable control methods by making use of quasi-steady-state time-series (QSTS) software …


Flexure Properties Of 3d Printed Nylon Carbon Fiber Composite And Stiffness Of 3d Printed Modified Cuttlefish Bone Structure, Shashikanth Reddy Jan 2019

Flexure Properties Of 3d Printed Nylon Carbon Fiber Composite And Stiffness Of 3d Printed Modified Cuttlefish Bone Structure, Shashikanth Reddy

Electronic Theses and Dissertations

Flexure strength is one of the most widely used mechanical properties to represent the mechanical behavior of the composite. Fiber reinforcements increase the flexure strength of a composite. Specifically, there has been tremendous growth in the use of Carbon Fiber (CF) in the manufacturing industry due to its significant contribution to enhance the mechanical properties of a composite. Fiber orientation, void content, bonding between the layers (delamination), and fiber distribution are some of the factors that affect the flexure strength of a reinforced composite. The laminate (composite with reinforced layers) composites, has been a focus of study by researchers from …


Modeling Runoff From Small Agricultural Watersheds In Eastern South Dakota, Bryce Siverling Jan 2019

Modeling Runoff From Small Agricultural Watersheds In Eastern South Dakota, Bryce Siverling

Electronic Theses and Dissertations

The capability to be able to consistently and accurately model any problem has potential time and money savings. The present study aimed to determine if the Natural Resources Conservation Service’s Curve Number (CN) model or the more detailed Soil and Water Assessment Tool (SWAT) Model can consistently and accurately model runoff events from small agricultural fields in Eastern South Dakota. The overall goal was to better understand models used to predict runoff and determine if they can produce accurate estimates of runoff from the watersheds being studied. Runoff measurements were collected from an agricultural field located south of Coleman, South …