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Graduate Theses and Dissertations

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Full-Text Articles in Engineering

Towards Utilization Of Distributed On-Chip Power Delivery Against Em Side-Channel Attacks, Ahmed Waheed Khan Apr 2018

Towards Utilization Of Distributed On-Chip Power Delivery Against Em Side-Channel Attacks, Ahmed Waheed Khan

Graduate Theses and Dissertations

Non-invasive side-channel attacks (SCAs) are potent attacks on a cryptographic circuit that can reveal its secret key without requiring lots of equipment. EM side-channel leakage is typically the derivative of the power consumption profile of a circuit. Since the fluctuations of the supply voltage strongly depend on the topology and features of the power distribution network (PDN), design of the PDN has a direct impact on EM side-channel leakage signature.

In this thesis, we explore the security implications of distributed on-chip voltage regulators against EM side-channel attacks. Extensive HFSS simulations have demonstrated that the maximum EM radiation can be reduced ...


Investigations On Frp-Concrete Bond, Mostfa Al Azzawi Apr 2018

Investigations On Frp-Concrete Bond, Mostfa Al Azzawi

Graduate Theses and Dissertations

This dissertation presents findings from three separate investigations, a laboratory study and two field studies that evaluated the durability of the Fiber Reinforced Polymer (FRP)-concrete bond. The laboratory study explored the role of porosity on CFRP-concrete bond following immersion in warm water. Two disparate field studies measured residual bond after 20 years outdoor exposure of FRP repairs of full-size masonry walls and after 12 years for partially submerged piles supporting the Friendship Trail Bridge, Tampa Bay.

The ACI 440 code requires the same surface preparation for all externally bonded FRP concrete repairs. This disregards the role of porosity that ...


Initial Beam Access Schemes For Millimeter Wave Cellular Networks, Mohammed Jasim Apr 2018

Initial Beam Access Schemes For Millimeter Wave Cellular Networks, Mohammed Jasim

Graduate Theses and Dissertations

Millimeter wave technologies present an appealing solution for increasing data throughputs as they provide abundant contiguous channel bandwidths as compared to conventional microwave networks. However, millimeter wave technologies suffer from severe propagation limitations and channel impairments such as atmospheric attenuation and absorption, path and penetration losses, and blockage sensitivity. Therefore, phased arrays and beamforming technologies are necessary to compensate for the degraded signal levels due to the aforementioned factors. Namely, base stations and mobile stations utilize directional transmission in the control- and data- plane for an enhanced channel capacity, which results in initial access challenges due to the absence of ...


Multi-Objective Resource Provisioning In Network Function Virtualization Infrastructures, Diogo Oliveira Apr 2018

Multi-Objective Resource Provisioning In Network Function Virtualization Infrastructures, Diogo Oliveira

Graduate Theses and Dissertations

Network function virtualization (NFV) and software-dened networking (SDN) are two recent networking paradigms that strive to increase manageability, scalability, pro- grammability and dynamism. The former decouples network functions and hosting devices, while the latter decouples the data and control planes. As more and more service providers adopt these new paradigms, there is a growing need to address multi-failure conditions, particularly those arising from large-scale disaster events. Overall, addressing the virtual network function (VNF) placement and routing problem is crucial to deploy NFV surviv- ability. In particular, many studies have inspected non-survivable VNF provisioning, however no known work have proposed survivable ...


Integration And Cross-Coupling Of A Notched-Turbine Symbiotic Power Source For Implantable Medical Devices, Samuel Perez Apr 2018

Integration And Cross-Coupling Of A Notched-Turbine Symbiotic Power Source For Implantable Medical Devices, Samuel Perez

Graduate Theses and Dissertations

The purpose of this research is to design and integrate a symbiotic notched-turbine energy generator for implantation as a cross-coupled system capable of continuously and perpetually powering an electronic implantable medical device (IMD), which is a device designed to operate inside the body of a higher mammal to enhance, correct or provide the body with a function that has deviated from the norm or has stopped altogether. The list of IMDs available for implantation keeps growing every year, one of the newest being the VBLOC, produced by EnteroMedics®, and approved by the Food and Drug Administration (FDA) on January 15th ...


Computational Discovery Of Energetic Polynitrogen Compounds At High Pressure, Brad A. Steele Apr 2018

Computational Discovery Of Energetic Polynitrogen Compounds At High Pressure, Brad A. Steele

Graduate Theses and Dissertations

High-nitrogen-content energetic compounds containing multiple N-N bonds are an attractive alternative towards developing new generation of environmentally friendly, and more powerful energetic materials. High-N content translates into much higher heat of formation resulting in much larger energy output, detonation pressure and velocity upon conversion to large amounts of non-toxic, strongly bonded N2 gas. This thesis describes recent advances in the computational discovery of group-I alkali and hydrogen polynitrogen materials at high pressures using powerful first-principles evolutionary crystal structure prediction methods. This is highlighted by the discovery of a new family of materials that consist of long-sought after all-nitrogen N􀀀 5 ...


In Situ Extrinsic Doping Of Cdte Thin Films For Photovoltaic Applications, Imran Suhrid Khan Mar 2018

In Situ Extrinsic Doping Of Cdte Thin Films For Photovoltaic Applications, Imran Suhrid Khan

Graduate Theses and Dissertations

The Cadmium Telluride thin film solar cell is one of the leading photovoltaic technologies. Efficiency improvements in the past decade made it a very attractive and practical source of renewable energy. Considering the theoretical limit, there is still room for improvement, especially the cell’s open circuit voltage (VOC). To improve VOC, the p-type carrier concentration and minority carrier lifetime of the CdTe absorber needs to be improved. Both these parameters are directly related to the point defect distribution of the semiconductor, which is a function of deposition stoichiometry, dopant incorporation and post-deposition treatments.

CdTe films were deposited by the ...


Three Dimensional Direct Print Additively Manufactured High-Q Microwave Filters And Embedded Antennas, Derar Fayez Hawatmeh Mar 2018

Three Dimensional Direct Print Additively Manufactured High-Q Microwave Filters And Embedded Antennas, Derar Fayez Hawatmeh

Graduate Theses and Dissertations

The need for miniaturized, and high performance microwave devices has focused significant attention onto new fabrication technologies that can simultaneously achieve high performance and low manufacturing complexity. Additive manufacturing (AM) has proven its capability in fabricating high performance, compact and light weight microwave circuits and antennas, as well as the ability to achieve designs that are complicated to fabricate using other manufacturing approaches. Direct print additive manufacturing (DPAM) is an emerging AM process that combines the fused deposition modeling (FDM) of thermoplastics with micro-dispensing of conductive and insulating pastes. DPAM has the potential to jointly combine high performance and low ...


Promoter Effects On Iron-Based, Sba-15 Supported Ultra-High Temperature Fischer- Tropsch Catalysts, David P. Weber Mar 2018

Promoter Effects On Iron-Based, Sba-15 Supported Ultra-High Temperature Fischer- Tropsch Catalysts, David P. Weber

Graduate Theses and Dissertations

Promoter effects on SBA-15 supported iron Fischer-Tropsch catalysts were investigated for their potential to improve high temperature catalyst performance. FTS catalysts promoted by manganese (0.15%-1.4%), copper (0.15%-1%), and potassium (0.5%-3%), with all percentages stated on the basis of mass percentage of final catalysts, were prepared and tested at 430°C and ambient pressure in a fixed bed reactor. Manganese showed the ability to promote the FT reaction, increasing both the CO conversion and the average chain length of hydrocarbon products. Compared to the unpromoted catalyst composed only of iron supported on SBA-15, 1 ...


Assessment Of Drinking Water Quality Management And A Treatment Feasibility Study For Brick By Brick Water Storage Tanks In Rakai Uganda, James V. Murduca Mar 2018

Assessment Of Drinking Water Quality Management And A Treatment Feasibility Study For Brick By Brick Water Storage Tanks In Rakai Uganda, James V. Murduca

Graduate Theses and Dissertations

Reliable access to safe drinking water is one necessity for humans to live without concern for major health risks. The overall goal of this research is to improve the public health, through improved drinking water, for communities in the Rakai District in Uganda, directly, and other communities in the world, indirectly, via dissemination of knowledge. This study specifically assessed the knowledge of drinking water quality in regards to public health, their sanitation measures, and water treatment methods for users of Brick by Brick rainwater harvesting tanks in the Rakai District (N = 28) by using a knowledge, attitudes, and practice survey ...


Field Testing Of Affordable Well Head Protection For Locally Manufactured, Self-Supply Pitcher Pumps On Manually Driven Tubewells In Madagascar, Michal Usowicz Mar 2018

Field Testing Of Affordable Well Head Protection For Locally Manufactured, Self-Supply Pitcher Pumps On Manually Driven Tubewells In Madagascar, Michal Usowicz

Graduate Theses and Dissertations

Lack of water access is an issue of global importance. The WHO and UNICEF’s Joint Monitoring Program estimated that in 2015 71% of the world’s population used a safely managed drinking water source and 89% of the world’s population used an improved water source within a 30-minute round trip of home. Madagascar’s national statistics lags far behind these global statistics with 54% of the population using improved water sources, 31% using unimproved water sources, and 16% with no service at all.

This research studied water access in Madagascar with self-supply Pitcher Pumps attached on hand-driven tubewells ...


Impact Of Substrate To Inoculum Ratio On Methane Production In High Solids Anaerobic Digestion (Hs-Ad) Of Food Waste, Yard Waste, And Biosolids, Phillip James Dixon Mar 2018

Impact Of Substrate To Inoculum Ratio On Methane Production In High Solids Anaerobic Digestion (Hs-Ad) Of Food Waste, Yard Waste, And Biosolids, Phillip James Dixon

Graduate Theses and Dissertations

High solids anaerobic digestion (HS-AD) is an alternative for managing the organic fraction of municipal solids waste (MSW), which produces mainly methane (CH4) and fertilizer as byproducts. HS-AD offers a potentially more economically and environmentally sustainable option compared with landfilling or incineration waste-to-energy facilities. However, HS-AD is a complex process requiring specific microbial communities working together symbiotically. Previous studies have found that the substrate to inoculum (S/I) ratio affects CH4 production and yield in HS-AD reactors by affecting substrate mass and energy transfer as well as microbial activity. In this thesis, biochemical methane potential (BMP) assays were used to ...


Comparison Of Thermal Glove Wrist-Hand Orthoses In Their Effectiveness On Rheumatoid Arthritis, Brittany E. Mott Mar 2018

Comparison Of Thermal Glove Wrist-Hand Orthoses In Their Effectiveness On Rheumatoid Arthritis, Brittany E. Mott

Graduate Theses and Dissertations

Rheumatoid arthritis (RA) is an autoimmune disease affecting nearly 1% of the world’s population with symptoms such as inflammation, pain, and reduced strength [1]. Physicians and scientists work to develop pharmaceuticals and medical devices aimed at decreasing the symptoms associated with RA to better the lives of those affected. One of the most recent developments is the addition of thermal therapy gloves to the array of upper limb orthoses available to patients with RA. It was hypothesized that this study will show that orthoses in the form of thermal therapy gloves are beneficial to the patients by reducing symptoms ...


Embedded System Design Of Low-Power Wearable Bioelectronic Devices, Matthew S. Hopper Mar 2018

Embedded System Design Of Low-Power Wearable Bioelectronic Devices, Matthew S. Hopper

Graduate Theses and Dissertations

The miniaturization of electronics in modern times has enabled the possibility of creating a “continuity of care” using small wearable bioelectronic devices. Using wearable devices, such as the Fitbit or Garmin fitness trackers, allows for the exchange of data between devices which can be used to improve the accuracy of data analysis and thus patient health.

In this thesis work, three wearable bioelectronic devices are proposed: an EOG-based eye-gaze tracking assistive technology device for the physically disabled to control a computer cursor, a battery-operated miniaturized polysomnograph that can store and transmit data wirelessly to sleep technicians and a trauma-detecting personal ...


Design And Testing Of A Linear Compliant Mechanism With Adjustable Force Output, William Niemeier Mar 2018

Design And Testing Of A Linear Compliant Mechanism With Adjustable Force Output, William Niemeier

Graduate Theses and Dissertations

This thesis presents a novel compliant mechanism with adjustable force output. The force comes from the bending of a rectangular cross section beam within the mechanism. By rotating this beam with a stepper motor, the force output of the mechanism changes. A model was made to simulate this mechanism, and a prototype was made based off of this data. A test apparatus was constructed around this mechanism, and a series of tests were performed. These tests adjusted parameters such as beam rotation speed and weight in order to characterize the system. Adjustments were made based on this information and the ...


Defect Detection In Additive Manufacturing Utilizing Long Pulse Thermography, James Pierce Mar 2018

Defect Detection In Additive Manufacturing Utilizing Long Pulse Thermography, James Pierce

Graduate Theses and Dissertations

Additive Manufacturing (AM), over the years, has seen a tremendous amount of research for improving the manufacturability of materials into final products. The main advantages of additive manufacturing are the minimizing of waste material as it is an additive process. As well as the ability to create custom low-volume products without the need for creation of expensive tooling or programming before manufacturing begins. Because of these advantages, however, AM is susceptible to unique challenges in the quality side of manufacturing. These challenges include minimizing and detecting defects during the build. The focus of this research looks at the capability of ...


Modeling Corrosion Damage And Repair To A 3, Joseph R. Scott Mar 2018

Modeling Corrosion Damage And Repair To A 3, Joseph R. Scott

Graduate Theses and Dissertations

The main purpose of this study was to investigate and implement a repair design for corrosion damaged bridge bents in order to resist lateral loading, such as wind loads or ship impact. Using the results from a one-third scale bridge bent constructed and tested for a previous study, non-linear modeling was used to simulate the same corrosion damage and load response. The principle variable considered was damage, represented as a percent of effective area loss of prestressing steel within a designated damage zone along the length of piles. Other influencing variables included: prestress transfer length, localized loss in prestress due ...


Analysis Of Ni And Fe-Based Alloys For Turbine Seal Ring Applications, Dawei She Mar 2018

Analysis Of Ni And Fe-Based Alloys For Turbine Seal Ring Applications, Dawei She

Graduate Theses and Dissertations

Metal sealing rings have been used widely in compressors, turbines and hydraulic devices. Such rings can extend out due to elasticity, and keep close contact with the valve wall, resulting in the formation of a functional seal under pressure. In this project, the failure of metal sealing rings is considered. Sealing component failure due to stress relaxation can threaten the safety of the whole steam turbine. The object of this study was to examine the stress relaxation response and corresponding changes in microstructure of metal sealing rings used in nuclear steam turbine under high temperature and applied stress. The two ...


Non-Precious Metal Catalysts For Oxygen Reduction Reaction In Alkaline Solutions, Zhewen Yin Mar 2018

Non-Precious Metal Catalysts For Oxygen Reduction Reaction In Alkaline Solutions, Zhewen Yin

Graduate Theses and Dissertations

Mesoporous WO3 powders were prepared via sol-gel processing synthesis using nonionic surfactant Pluronic (P-123) as the template. The influences of heating temperature on the pore structure and properties of WO3 powders were investigated. Three kinds of modifications were compared and evaluated after finding out the best heating condition. Different amount of lanthanum was doped into mesoporous WO3 to improve its Oxygen Reduction Reaction (ORR) activity. Several factors contributing to the increase of catalytic performance were discussed. Vulcan carbon powder was also used as a support to increase the catalysts’ electrical conductivity as well as dispersity. The component, microstructure and specific ...


Developing Motion Platform Dynamics For Studying Biomechanical Responses During Exercise For Human Spaceflight Applications, Kaitlin Lostroscio Mar 2018

Developing Motion Platform Dynamics For Studying Biomechanical Responses During Exercise For Human Spaceflight Applications, Kaitlin Lostroscio

Graduate Theses and Dissertations

In future human spaceflight missions, with prolonged exposure to microgravity, resistive and aerobic exercises will be countermeasures for bone loss, muscle loss, and decreased aerobic capacity. Two of the exercises of interest are squats and rowing. The cyclic forces produced during these exercises are at relatively low frequencies which are likely to excite structural resonances of space vehicles. Vibration Isolation Systems (VIS) are being designed to be paired with future exploration exercise devices in order to prevent these cyclic exercise forces from impacting the space vehicle. The VIS may be configured such that a platform supports the human and exercise ...


Design And Implementation Of A Ferrocement Improved Cookstove In Rural Panama, Josh Donegan Mar 2018

Design And Implementation Of A Ferrocement Improved Cookstove In Rural Panama, Josh Donegan

Graduate Theses and Dissertations

Household air pollution contributes to the premature death of more than 4 million people annually. Improved cookstoves are one technological intervention that can potentially reduce exposure to household air pollution. However, improved cookstove implementation programs need to consider measures to increase sustainability and promote long-term adoption. The objectives of this research were 1) to develop and implement a new ferrocement cookstove for Peña Blanca, a rural indigenous community in the Ngäbe-Bugle region of Panama, 2) to evaluate its potential sustainability in comparison to the most common cooking technologies observed in the community, 3) to prepare a construction manual for the ...


Design Of Micro-Scale Energy Harvesting Systems For Low Power Applications Using Enhanced Power Management System, Majdi M. Ababneh Mar 2018

Design Of Micro-Scale Energy Harvesting Systems For Low Power Applications Using Enhanced Power Management System, Majdi M. Ababneh

Graduate Theses and Dissertations

The great innovations of the last century have ushered continuous progress in many areas of technology, especially in the form of miniaturization of electronic circuits. This progress shows a trend towards consistent decreases in power requirements due to miniaturization. According to the ITRS and industry leaders, such as Intel, the challenge of managing and providing power efficiency still persist as scaling down of devices continues. A variety of power sources can be used in order to provide power to low power applications. Few of these sources have favorable characteristics and can be designed to deliver maximum power such as the ...


Effectiveness Of Biocide Substitution And Management Plan Implementation For The Control Of, Adelmarie Bones Mar 2018

Effectiveness Of Biocide Substitution And Management Plan Implementation For The Control Of, Adelmarie Bones

Graduate Theses and Dissertations

After the notorious outbreak and discovery of Legionella bacteria in 1976, the waterborne pathogen was added to the list of disease-causing agents associated with the built environment. Legionella pneumophila was discovered when it was identified as the agent that caused 34 deaths and an outbreak of pneumonia-like symptoms in several attendees of the 1976 American Legion Convention held in Philadelphia (OSHA, 2017).

Recently published data from the year 2015 reported more than 6,000 Legionnaires’ cases identified in the United States (CDC, 2016). This is a concerning number given that one in every ten infected persons will die of the ...


Assessing The Impacts Of Climate Change On Streamflow And Reservoir Operation In Central Florida, Toni Panaou Jan 2018

Assessing The Impacts Of Climate Change On Streamflow And Reservoir Operation In Central Florida, Toni Panaou

Graduate Theses and Dissertations

Climate change is a global concern as it may affect many aspects of life, including water supply. A tool used to model climate change’s impacts is called a General Circulation Model (GCM). GCMs project future scenarios including temperature and precipitation, but these are designed at a coarse resolution and require downscaling for employment for regional hydrologic modeling. There is a vast amount of research on downscaling and bias-correcting GCMs data, but it is unknown whether these techniques alter precipitation signals embedded in these models or reproduce climate states that are viable for water resource planning and management. Using the ...


Evaluating Manufacturing Energy Consumption For A Part Using Geometry, Alicia M. Guzman Gutierrez Jan 2018

Evaluating Manufacturing Energy Consumption For A Part Using Geometry, Alicia M. Guzman Gutierrez

Graduate Theses and Dissertations

The decisions made during the design process have a significant impact on the manufacturing of a part. Besides technical and functional requirements, designers also weigh in the effects that design geometry, material, and specifications will have on energy consumption. Since most of a part’s sustainability impact is defined during the design process, it is important that engineers consider sustainability throughout the design process. Existing tools that assess the sustainability of designs do not consider the geometric complexity of designs and provide little guidance for engineers to improve designs.

Based on the notion that more complex designs will require more ...


Broadly Defined Synthesis And Properties Of Phase Change Materials, Bokki Min Jan 2018

Broadly Defined Synthesis And Properties Of Phase Change Materials, Bokki Min

Graduate Theses and Dissertations

Phase change materials are currently used in numerous applications such as sensor, memory, detector, etc. due to change in properties when external stimuli are applied. Over the past few decades, nanostructured phase change materials have shown enhanced properties and characteristics compared to the conventional bulk phase change materials. Transition metal chalcogenides are reported to undergo thermally triggered phase transitions, yet there is still significant room for improvements for nanostructured FeTe2. Also, two-dimensional MXenes are reported to have multiple phases due to change in the surface chemistry.

This thesis proposes solution phase synthesis and properties of FeTe2 nanostructures with different Te ...


Remote Maintenance Assistance Using Real-Time Augmented Reality Authoring, Jonathan A. Schlueter Jan 2018

Remote Maintenance Assistance Using Real-Time Augmented Reality Authoring, Jonathan A. Schlueter

Graduate Theses and Dissertations

Maintenance operations and lifecycle engineering have largely been considered one of the most expensive and time-consuming components for industrial equipment. Numerous organizations continually devote large quantities of resources towards maintaining equipment. As such, any optimizations that would reduce maintenance errors and expenses could lead to substantial time and cost savings. Unfortunately, there are often not enough specialists to meet the demand, forcing localized technicians to perform on-site maintenance on equipment outside their area of expertise. Augmented reality (AR) is one technology that has already been shown to improve the maintenance process. While powerful, AR has its own set of challenges ...


Using Google Cardboard To Perform A Visual Field Screening Test, Dhanraj Selvaraj Jan 2018

Using Google Cardboard To Perform A Visual Field Screening Test, Dhanraj Selvaraj

Graduate Theses and Dissertations

The visual field test is used to detect areas on the retina where there is a loss of vision. The equipment used to conduct the test is bulky and can cost a significant amount to patients to take the test. Google Cardboard is an inexpensive headset which is paired with a mobile phone to run virtual reality applications. In this work, a visual field screening test is developed to enable people to do an eye exam with a low-cost and portable device such as a Google Cardboard and a smart phone. The Google Cardboard application helps reduce the cost of ...


Development Of Methods To Improve The Accuracy And Efficiency Of Unsteady Incompressible Flow Simulation, Matthew Vincent Fischels Jan 2018

Development Of Methods To Improve The Accuracy And Efficiency Of Unsteady Incompressible Flow Simulation, Matthew Vincent Fischels

Graduate Theses and Dissertations

The runtime of unsteady incompressible flows were reduced through different techniques in the formulation and solution of the governing equations. The implicit Runge-Kutta based IRK-SIMPLER algorithm was developed and compared to the Crank-Nicholson based SIMPLER and the explicit RK-SIMPLER algorithms. The IRK-SIMPLER algorithm was tested for steady and unsteady problems, both on structured Cartesian and unstructured vertex-centered median-dual grids, and proved to be an accurate and robust algorithm that also required less runtime. Further, a second order unstructured Flux Corrected Method improved the accuracy of flux calculation with minimal/negligible increase in runtime. The Flux Corrected Method provided a small ...


Laboratory Study Of Parameters Influencing Tornado Flow Field And Tornado Loading On Low-Rise Buildings, Alireza Razavi Jan 2018

Laboratory Study Of Parameters Influencing Tornado Flow Field And Tornado Loading On Low-Rise Buildings, Alireza Razavi

Graduate Theses and Dissertations

Tornado is one of the deadliest natural hazards in the U.S. with a 10-year average fatality exceeding 100. The annual property-insured loss of more than $1 billion makes it even more problematic. To mitigate and address the loss caused by this natural hazard, it is important to (a) understand the tornado flow field and parameters that affect it, as well as (b) assess the tornado-induced wind loads on low-rise buildings and their components and the parameters that affect the peak wind loads for the purpose of improving their design. The above reasoning drives the two primary objectives of this ...