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Full-Text Articles in Engineering

An Energy-Efficient Semi-Partitioned Approach For Hard Real-Time Systems With Voltage And Frequency Islands, Jesse W. Patterson May 2016

An Energy-Efficient Semi-Partitioned Approach For Hard Real-Time Systems With Voltage And Frequency Islands, Jesse W. Patterson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Embedded devices are computer systems with a dedicated function, such as kitchen appliances, electronic toys, phones, et cetera. Embedded devices are commonplace, and many are expected to respond to users in real-time. Such devices are often categorized as real-time embedded systems as they differ from other embedded systems in that work performed by a real-time embedded system must be scheduled such that timeliness can be provided to the user (e.g. when someone is talking on a phone, the phone needs to be able to schedule the sending and receiving of data in a timely manner such that the conversation is …


Achieving Uniform Flow Distribution In Compact Irrigation Splitter Boxes With High Flow Rates, Joshua Ryan Hogge May 2016

Achieving Uniform Flow Distribution In Compact Irrigation Splitter Boxes With High Flow Rates, Joshua Ryan Hogge

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In many irrigation systems and networks, there are multiple water users and shareholders who take their water from different locations along a single canal or pipeline. Often, irrigation splitter boxes are used to divert water to multiple shareholders from a single location. The splitter boxes, which can be small and compact, are generally installed at different locations along a piped irrigation supply line. The purpose of a splitter box is to split a specific amount of water so that each user receives their allotted portion, regardless of the flow rate in the system.

Each splitter box usually includes two compartments, …


Visualization Of Three-Dimensional Models From Multiple Texel Images Created From Fused Ladar/Digital Imagery, Cody C. Killpack May 2016

Visualization Of Three-Dimensional Models From Multiple Texel Images Created From Fused Ladar/Digital Imagery, Cody C. Killpack

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The ability to create three-dimensional (3D) images offers a wide variety of solutions to meet ever increasing consumer demands. As popularity for 3D cinema and television continues to grow, 3D images will remain an important area of research and development. While there are a variety of ways to create a 3D model, textel images are quickly become the preferred solution that has been captured with a texel camera. The combination of multiple texel images taken around a scene can be used to form a texel model. Offering both visual and dimensional accuracy, texel models are becoming invaluable tools for disaster …


An Optical System To Transform The Output Beam Of A Quantum Cascade Laser To Be Uniform, Jordan M. Jacobson May 2016

An Optical System To Transform The Output Beam Of A Quantum Cascade Laser To Be Uniform, Jordan M. Jacobson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Quantum cascade lasers (QCLs) are a candidate for calibration sources in space-based remote sensing applications. However, the output beam from a QCL has some characteristics that are undesirable in a calibration source. These characteristics need to be mitigated before QCLs can be used as calibration sources. This study presents the design and implementation of an optical system that removes the undesirable characteristics from a QCL output beam, so it can be used as a calibration source.


Accumulation And Release Of Trace Inorganic Contaminants From Biofilm Matrices Produced And Challenged Under Drinking Water Distribution System Conditions, William W. Kent May 2016

Accumulation And Release Of Trace Inorganic Contaminants From Biofilm Matrices Produced And Challenged Under Drinking Water Distribution System Conditions, William W. Kent

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Drinking water distribution systems (DWDS) are used to transport drinking water from the place of treatment to your home. DWDS are made of many types of pipe materials and have the potential to accumulate materials such as iron and manganese oxides and biofilms that serve as reservoirs for toxic trace inorganic contaminants (TICs) such as thallium, arsenic, and lead. These materials can be stable, but changes in water quality or a physical disturbance such as road construction or water use changes may result in a TIC release, causing water quality degradation. This study used glass columns filled with glass beads …


Efficient Device To Device Communications Underlaying Heterogeneous Networks, Xue Chen May 2016

Efficient Device To Device Communications Underlaying Heterogeneous Networks, Xue Chen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Device-to-Device communications have the great potential to bring significant performance boost to the conventional heterogeneous network by reusing cellular resources. In cellular networks, Device-to-Device communication is defined as two user equipments in a close range communicating directly with each other without going through the base station, thus offloading cellular traffic from cellular networks. In addition to improve network spectral efficiency, D2D communication can also improve energy efficiency and user experience.

However, the co-existence of D2D communication on the same spectrum with cellular users can cause severe interference to the primary cellular users. Thus the performance of cellular users must be …


Evapotranspiration Estimation: A Study Of Methods In The Western United States, Clayton S. Lewis May 2016

Evapotranspiration Estimation: A Study Of Methods In The Western United States, Clayton S. Lewis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Theoretical water use of well-watered vegetation in the western United States was investigated by comparing a gridded dataset developed from satellite and ground instruments to weather stations representative of irrigated agricultural conditions. Since wetter environments are cooler and therefore subject to lower levels of evaporation than the same scenario with warmer temperatures, models derived from dryland and often populated areas overestimate potential plant needs in semi-arid or arid conditions. Evaluation of the model revealed an acceptable fit for air temperatures and solar radiation but with less confidence in humidity and wind speeds. Ultimately, the last two parameters were minor components …


Blind Front-End Processing Of Dynamic Multi-Channel Wideband Signals, Kevin Jackson May 2016

Blind Front-End Processing Of Dynamic Multi-Channel Wideband Signals, Kevin Jackson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Society today relies heavily on the exchange of information via wireless communication. Such communication provides the means of transferring information from point A to point B over the air. In order to accomplish this, a minimum of two devices is required: a transmitter and a receiver. Just as people must speak the same language in order to communicate, the receiver must know how the transmitter communicates in order to make sense of the data being transmitted. For multiple wireless communication system to coexist, they must each speak a unique language, which in the communications world is referred to as modulation. …


Investigating The Effect Of Carbon Nanotube Functionalization In A Polydimethylsiloxane Composite Through Use Of A Stepped Bar Apparatus, Matthew I. Ralphs May 2016

Investigating The Effect Of Carbon Nanotube Functionalization In A Polydimethylsiloxane Composite Through Use Of A Stepped Bar Apparatus, Matthew I. Ralphs

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Thermal interface materials (TIMs) are used in transporting heat away from a circuit or electronic module. Composite materials are a popular research area for TIMs because they allow the desired properties to be joined in a composite to take advantage of the best properties from all the constituents involved. The composite selected for this study uses carbon nanotubes (CNT) as the filler and an elastomeric polymer for the matrix, specifically a multiwalled carbon nanotube (MWCNT) / polydimethylsiloxane (PDMS) composite. This study looks at chemical modification (functionalization) of the CNTin an effort to produce a better bond between the CNT and …


Thermal Property Measurement Of Thin Fibers By Complementary Methods, Troy Robert Munro May 2016

Thermal Property Measurement Of Thin Fibers By Complementary Methods, Troy Robert Munro

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Thin fibers are prevalent in many engineering materials. Measuring how well heat transfers in such small fibers can be difficult to determine, and previous methods have led to erroneous results. This dissertation details three proposed methods to improve the measurement of the thermal conductivity, thermal diffusivity, and volumetric heat capacity of thin fibers. Of particular interest is natural and synthetic spider silks because previously published values of the natural silk thermal conductivity was similar to copper, an excellent thermal conductor.

The three methods developed are the improved transient electrothermal technique (which was redeveloped to include radiation and convection heat losses …


Development Of A Three-Dimensional High-Order Strand-Grids Approach, Oisin Tong May 2016

Development Of A Three-Dimensional High-Order Strand-Grids Approach, Oisin Tong

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The strand-Cartesian grid approach is a unique method of generating and computing fluid dynamic simulations. The strand-Cartesian approach provides highly desirable qualities of fully-automatic grid generation and high accuracy. This work focuses on development of a high-accuracy methodology (high-order scheme) on strand grids for two and three dimensions.

In this work, the high-order scheme is extended to high-Reynolds number computations in both two and three dimensions with the Spalart-Allmaras turbulence model and the Menter SST turbulence model. In addition, a simple limiter is explored to allow the high-order scheme to accurately predict discontinuous flows.

Extensive verification and validation is conducted …


An Automatic Algorithm For Textured Digital Elevation Model Formation Using Aerial Texel Swaths, Taylor C. Bybee May 2016

An Automatic Algorithm For Textured Digital Elevation Model Formation Using Aerial Texel Swaths, Taylor C. Bybee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The process of creating a 3D terrain map of an area is a challenging, computationally intensive task. There are two main camps of established methods doing this, with varying degrees of accuracy and cost. Using the established methods, there is a trade-off between accuracy and cost. The first method involves using many aerial images to detect disparity between points in the images. This is a difficult task as it requires a lot of computer processing with varying degrees of reliability. In addition, this method does not make any direct distance measurements. Secondly, using high-precision and high-cost lasers and positioning equipment, …


Investigation Of The Tailoring Steps In Pradimicin Biosynthesis, Kandy L. Napan May 2016

Investigation Of The Tailoring Steps In Pradimicin Biosynthesis, Kandy L. Napan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research focused on the investigation of the late steps in the biosynthetic pathway of the novel antifungal and antiviral pradimicins A-C. Pradimicins were first isolated from the soil bacterium Actinomadura hibisca. These bioactive molecules are assembled by a type II polyketide biosynthetic pathway. Although the biosynthetic gene cluster of pradimicin has been identified, the functions of the biosynthetic genes and how they work collaboratively to form the final structures of pradimicins remain unknown. This research aims to functionally characterize the enzymes involved in the late steps of the biosynthetic route.

The early biosynthetic steps of pradimicins have been …


Traffic Sign Management: Data Integration And Analysis Methods For Mobile Lidar And Digital Photolog Big Data, Majid Khalilikhah May 2016

Traffic Sign Management: Data Integration And Analysis Methods For Mobile Lidar And Digital Photolog Big Data, Majid Khalilikhah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Traffic signs often convey critical information to drivers. However, traffic signs are only effective when clearly visible and legible. This study aims to determine the effects of various damage and deterioration forms on sign retroreflectivity, identify the most important factors affecting traffic sign visual condition, predict traffic sign vandalism that obstructs critical messages to drivers, and identify important environmental factors contributing to the temporary obstruction of the sign messages. To do so, two data sets are used. A sample data of over 1,700 signs was manually collected in the field, and the background retroreflectivity of each sign was measured using …


Rudder Augmented Trajectory Correction For Unmanned Aerial Vehicles To Decrease Lateral Image Errors Of Fixed Camera Payloads, Thomas M. Fisher May 2016

Rudder Augmented Trajectory Correction For Unmanned Aerial Vehicles To Decrease Lateral Image Errors Of Fixed Camera Payloads, Thomas M. Fisher

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

When using small unmanned aerial vehicles (UAVs) with cameras onboard for ground surveying, two competing problems arise. First is the desire to keep the camera sensor parallel with the ground and second is to maintain the proper flight path. When the cameras are physically fixed to the UAV and as the plane banks to maintain the desired path, the camera sensor is no longer kept parallel with the ground. This thesis focuses on a method called rudder augmented trajectory correction that allows for flat turns instead of banking the aircraft. Because of this, the camera is able to stay parallel …


Effects Of Radiation Heating On Additively Printed Hybrid Fuel Grain Oxidizer-To-Fuel Ratio Shift, Stephen L. Merkley May 2016

Effects Of Radiation Heating On Additively Printed Hybrid Fuel Grain Oxidizer-To-Fuel Ratio Shift, Stephen L. Merkley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis examined the hypothesis that radiative heat transfer in small-scale printed-fuel hybrid rocket motors is responsible for the observed decreasing oxidizer-to-fuel (O/F) ratio shift. The magnitude of the radiation term was negligible for the motor sizes and types of propellants that have been previously tested, but was reintroduced in this study. To prove this hypothesis, a detailed enthalpy balance model was developed and tested using experimental fuel regression rate data obtained from a variety of motor scales using additively-manufactured acrylonitrile butadiene styrene (ABS) fuel grains.


An Electromagnetic Coupling Model For Side-Channel Analysis, Michael L. Schena May 2016

An Electromagnetic Coupling Model For Side-Channel Analysis, Michael L. Schena

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presents an EM coupling model used to enhance power, side-channel measurements used in CPA. The Kalman filter is used to combine measurements of magnetic flux density with voltage or current traditionally used to measure power consumption. The DES encryption algorithm is used to evaluate CPA using EM coupled power measurements compared to traditional power measurements.


Carbon Dioxide Capture By Steel-Making Residues In A Fluidized Bed Reacto, Suhaib Mohammad Hameedi May 2016

Carbon Dioxide Capture By Steel-Making Residues In A Fluidized Bed Reacto, Suhaib Mohammad Hameedi

Theses

Global warming is one of the most challenging problems facing societies these days, and it is known to be caused by the increasing emissions of Green House Gases (GHG's), mainly CO2, from various human activities. To solve such a problem, or at least minimize its effects, several actions have been considered. One of these actions is carbon capture, which has many different options and techniques. This research focuses on the capture of CO2 through reactions with steel-making residues, an alkaline solid by-product of the steel-making process. The aim is to sequester CO2 and form carbonates, which …


Behavior Of Expansive Concrete-Filled Steel Tubular (Ecfst) Columns Under Axial Loadings, Abdulaziz Lazkani May 2016

Behavior Of Expansive Concrete-Filled Steel Tubular (Ecfst) Columns Under Axial Loadings, Abdulaziz Lazkani

Theses

Concrete-filled steel tubes (CFST) have been introduced in high-rise buildings in order to expedite construction and increase the confinement of concrete by the steel tube, and hence increase the capacity of the column cross-section. More recently, expansive additives (EAs) that counteract the shrinkage of concrete have been used in CFST to improve the bond between the concrete and steel tube. Although changing the confinement level exerted by the steel tube on concrete will have an impact on the behavior of CFSTs, little information is available regarding the influence of EAs on the mechanical characteristics of expansive concrete-filled steel tubular (ECFST) …


Recycling Ceramic Waste Powder And Its Usage As An Alternative Ingredient In Concrete, Dima Mamoun Kanaan May 2016

Recycling Ceramic Waste Powder And Its Usage As An Alternative Ingredient In Concrete, Dima Mamoun Kanaan

Theses

Green environment is a challenging concern to accomplish in today’s world. This could be accomplished through an effective and beneficial recycling system through reusing solid waste materials. The study and exploration of alternative ingredients for concrete-making industry started more than five decades ago. Concrete that contains solid waste is referred to as “Green” concrete. Ceramic tiles are widely used in most structures; its production creates waste powder. Using ceramic waste powder (CWP) as an ingredient to partially replace cement in concrete will have a positive and progressive environmental impact in addition will help reserve natural resources. In this study, CWP …


Microalgae Cell Quantification Using Electrical Parameters, Leena Osama Fahmi Saqer May 2016

Microalgae Cell Quantification Using Electrical Parameters, Leena Osama Fahmi Saqer

Theses

Electrical properties of living cells have been proven to play a significant role in understanding and characterizing the different biological activities of the cell. The objective of this work is to develop an electrical based technique for determining and estimating the number of microalgae cells in a suspension without the need for any sample treatments or pre-processing.

The proposed technique is based on the direct use of electrical capacitive model. The basic premise behind this idea is the electrical polarization of microalgae particles that get charged due to the application of an electric field. This wouldn’t cause any distortion or …


The Agricultural Growth And Malting Production Of Barley Grains In Northeast Tennessee And Southwest Virginia, Mark Evans Patton Mr. May 2016

The Agricultural Growth And Malting Production Of Barley Grains In Northeast Tennessee And Southwest Virginia, Mark Evans Patton Mr.

Electronic Theses and Dissertations

The purpose of this study is to explore the history and production processes of beer and examines the components that contribute to its brewing. The narrative will provide a timeline of the processes that are required to create the product of beer beginning with the agricultural products and following the brewing processes that result in beer as the finished product. I will also examine the business of agriculture and grain processing and will provide some historical perspectives of grain, beer, and malting. I will also consider whether the growing, processing, and malting of grains in the East Tennessee and Southwest …


Use Of Drone And Infrared Camera For A Campus Building Envelope Study, Raheem Taiwo Ariwoola May 2016

Use Of Drone And Infrared Camera For A Campus Building Envelope Study, Raheem Taiwo Ariwoola

Electronic Theses and Dissertations

Presently, there are concerns that buildings in the USA under-performs in terms of energy efficiency when compared with the original design specifications. A significant percentage of the energy loss in these buildings is associated with the building’s envelope. This study provides a qualitative and analytical understanding of the R-value, which indicates the thermal performance of the elements that make up a building envelope. Infrared thermography is used as a methodology to assess the thermal performance of envelopes of ten buildings on East Tennessee State University Campus. A Fluke Ti25 infrared hand-held camera and a DJI phantom-2 drone mounted with FLIR …


An Analysis Of Capital Cost Estimation Techniques For Chemical Processing, Omar Joel Symister May 2016

An Analysis Of Capital Cost Estimation Techniques For Chemical Processing, Omar Joel Symister

Theses and Dissertations

This research serves to compare the use of the capital cost estimation software, Aspen Capital Cost Estimator (ACCE), with other capital cost estimating methods specifically the module costing technique outlined by Richard Turton et al. and also a factorial costing technique outlined by Gavin Towler and Ray Sinnott. This study will compare popular process equipment found in the chemical process industries. The relationship between the capacities of the equipment, as it relates to the cost as well as operational pressures and materials of construction (MOC), will also be obtained and compared. The results of this study may be used by …


Flight Test Investigation On The Effects Of Aircraft Flap Configuration Change On Longitudinal Trim, Tiziano Bernard May 2016

Flight Test Investigation On The Effects Of Aircraft Flap Configuration Change On Longitudinal Trim, Tiziano Bernard

Theses and Dissertations

Loss of Control (LOC) in general aviation has been a topic of extensive study and analysis in the United States and the European Union due to a long series of aircraft accidents in the past decades. The National Transportation Safety Board (NTSB) has identified over 1500 accidents in the traffic pattern involving LOC in general aviation aircraft between 1982 and 2015. LOC has often been attributed to deficiencies in pilot training, and the typical recommendation to reduce the number of accidents is to provide further training in stalls and spins. The European Aviation Safety Agency (EASA) has performed research that …


Experimental, Numerical, And Analytical Slosh Dynamics Of Water And Liquid Nitrogen In A Spherical Tank, Jedediah Morse Storey May 2016

Experimental, Numerical, And Analytical Slosh Dynamics Of Water And Liquid Nitrogen In A Spherical Tank, Jedediah Morse Storey

Theses and Dissertations

Understanding, predicting, and controlling fluid slosh dynamics is critical to safety and improving performance of space missions when a significant percentage of the spacecraft’s mass is a liquid. Computational fluid dynamics simulations can be used to predict the dynamics of slosh, but these programs require extensive validation. Many experimental and numerical studies of water slosh have been conducted. However, slosh data for cryogenic liquids is lacking. Water and cryogenic liquid nitrogen are used in various ground-based tests with a spherical tank to characterize damping, slosh mode frequencies, and slosh forces. A single ring baffle is installed in the tank for …


A Method To Enhance The Heat Transfer Mechanism In Metal Particle Porous Beds With Applicability To Paramagnetic Materials For Hydrogen Storage, Shahin Shafiee May 2016

A Method To Enhance The Heat Transfer Mechanism In Metal Particle Porous Beds With Applicability To Paramagnetic Materials For Hydrogen Storage, Shahin Shafiee

Theses and Dissertations

This research introduces a heat transfer enhancement method for porous beds of either ferromagnetic and paramagnetic materials. Throughout this work, it is shown that applying magnetic fields, not only enhances the heat transfer rate in particle beds but also improves hydrogenation properties of lanthanum nickel. The first section of the work is focused on heat transfer in iron oxide beds under magnetism. This stage studies effect of different magnetic field configurations and intensities on conduction improvement. The second phase of the work, studies the effect of utilizing magnetic fields on hydriding properties of a selected metal hydride. Experimentation has proven …


Evaluation Of Unbound Pavement Layers Moduli Using The Miniaturized Pressuremeter Test, Alaa Mohammed Shaban May 2016

Evaluation Of Unbound Pavement Layers Moduli Using The Miniaturized Pressuremeter Test, Alaa Mohammed Shaban

Theses and Dissertations

A small version of pressuremeter known as Miniaturized Pressuremeter (MPMT) was designed and built to provide high quality pavement parameters. The device, which is a modified version of PENCEL Pressuremeter (PPMT) has a 6 inch inflatable probe capable of quickly and reliably measuring the stress-strain response of thin pavement layers. The MPMT stress-strain data can be used as inputs to evaluate existing pavement structures as a part of a pavement management system, and as critical inputs in empirical pavement design methods. To check in-situ operational performance of the new probe, twenty four MPMT and PPMT tests were performed in parallel …


Numerical Simulation Of Tip Clearance Impact On A Pumpjet Propulsor, Lin Lu, Guang Pan, Jing Wei, Yipeng Pan May 2016

Numerical Simulation Of Tip Clearance Impact On A Pumpjet Propulsor, Lin Lu, Guang Pan, Jing Wei, Yipeng Pan

Ocean Engineering and Marine Sciences Faculty Publications

Numerical simulation based on the Reynolds Averaged NaviereStokes (RANS) Computational Fluid Dynamics (CFD) method had been carried out with the commercial code ANSYS CFX. The structured grid and SST keu turbulence model had been adopted. The impact of noncondensable gas (NCG) on cavitation performance had been introduced into the Schnerr and Sauer cavitation model. The numerical investigation of cavitating flow of marine propeller E779A was carried out with different advance ratios and cavitation numbers to verify the numerical simulation method. Tip clearance effects on the performance of pumpjet propulsor had been investigated. Results showed that the structure and characteristics of …


The Impact Of Learning Curve Model Selection And Criteria For Cost Estimation Accuracy In The Dod, Candace Honious, Brandon Johnson, John J. Elshaw, A. B. Badiru Apr 2016

The Impact Of Learning Curve Model Selection And Criteria For Cost Estimation Accuracy In The Dod, Candace Honious, Brandon Johnson, John J. Elshaw, A. B. Badiru

Faculty Publications

The first part of this manuscript examines the impact of configuration changes to the learning curve when implemented during production. This research is a study on the impact to the learning curve slope when production is continuous but a configuration change occurs. Analysis discovered the learning curve slope after a configuration change is different from the stable learning curve slope pre-configuration change. The newly configured units were statistically different from previous units. This supports that the new configuration should be estimated with a new learning curve equation. The research also discovered the post-configuration slope is always steeper than the stable …