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Doctoral Dissertations

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Full-Text Articles in Engineering

Polymeric Peptide Mimics For Protein Delivery, Coralie Backlund Jan 2018

Polymeric Peptide Mimics For Protein Delivery, Coralie Backlund

Doctoral Dissertations

The plasma membrane is a major obstacle in the development and use of biomacromolecules for intracellular applications. Consequently, proteins with intracellular targets represent an enormous, yet under studied avenue for therapeutics. Extended research has aimed at facilitating intracellular delivery of exogenous proteins using protein transduction domains (PTDs), which allow transport of bioactive molecules into cells. Synthetic polymers, inspired by PTDs, provide a well-controlled platform to vary molecular architecture for structure activity relationship studies. Specifically, this thesis focuses on the use of ring-opening metathesis, a facile and efficient polymerization technique, through which we can vary structural parameters to optimize delivery of ...


Flood Risk Assessment, Management And Perceptions In A Changing World, Katherine Schlef Jan 2018

Flood Risk Assessment, Management And Perceptions In A Changing World, Katherine Schlef

Doctoral Dissertations

Floods are a global challenge that is increasing due to changes in climate and human populations. Using an interdisciplinary approach, this work contributes novel methodologies and knowledge to three key challenges associated with floods. The first chapter builds upon the atmospheric and statistical sciences to provide a general methodology for climate informed approaches to projecting long-term flood events based on large-scale ocean-atmospheric processes. The second chapter builds upon the engineering, decision analysis, and economics disciplines to integrate climate-informed projections with decision-scaling, a decision-making under uncertainty framework, to further flood risk management. The third chapter builds upon the social sciences to ...


Data Analytics For Stochastic Control And Prognostics In Cyber-Physical Systems, Shanshan Bi Jan 2018

Data Analytics For Stochastic Control And Prognostics In Cyber-Physical Systems, Shanshan Bi

Doctoral Dissertations

"In this dissertation, several novel cyber fault diagnosis and prognosis and defense methodologies for cyber-physical systems have been proposed. First, a novel routing scheme for wireless mesh network is proposed. An effective capacity estimation for P2P and E2E path is designed to guarantee the vital transmission safety. This scheme can ensure a high quality of service (QoS) under imperfect network condition, even cyber attacks. Then, the imperfection, uncertainties, and dynamics in the cyberspace are considered both in system model and controller design. A PDF identifier is proposed to capture the time-varying delays and its distribution. With the modification of traditional ...


Hydrodynamics Study Of The Bubble Columns With Intense Vertical Heat-Exchanging Tubes Using Gamma-Ray Computed Tomography And Radioactive Particle Tracking Techniques, Abbas Jawad Sultan Jan 2018

Hydrodynamics Study Of The Bubble Columns With Intense Vertical Heat-Exchanging Tubes Using Gamma-Ray Computed Tomography And Radioactive Particle Tracking Techniques, Abbas Jawad Sultan

Doctoral Dissertations

"Understanding the hydrodynamics of bubble columns with and without vertical heat-exchanging tubes is a necessity for the proper design, scale-up, and operation of these reactors. To achieve this goal, systematic experiments were performed to visualize and quantify the influence of the presence of vertical internal tubes on the gas holdup distributions and their profiles, axial liquid velocity, and turbulent parameters (i.e., normal and shear stresses; turbulent kinetic energy) by using advanced gamma-ray computed tomography (CT) and radioactive particle tracking (RPT). In this study, the experiments were conducted in 6- and 18-inch bubble columns with an air-water system as the ...


Origins And Seasonal Variation Of Disinfection Byproduct Precursors, Ran Zhao Jan 2018

Origins And Seasonal Variation Of Disinfection Byproduct Precursors, Ran Zhao

Doctoral Dissertations

Disinfection byproducts (DBPs) are formed from the disinfectant (e.g., chlorine) reacting with components of natural organic matter (NOM) in water drawn from surface water supplies, and are considered as the cause of potential serious human health problems. DBP precursors originate in large reservoirs from at least three types of sources: (1) watershed or allochthonous, (2) algal or autochthonous, and (3) bottom sediments or benthic. The properties of the NOM and the DBP precursor content of that NOM are unique to each source.

The first objective of this dissertation was to use temporal and spatial water quality data from a ...


A New Signal Processing Method For Acoustic Emission/Microseismic Data Analysis, Charles Mborah Jan 2018

A New Signal Processing Method For Acoustic Emission/Microseismic Data Analysis, Charles Mborah

Doctoral Dissertations

"The acoustic emission/microseismic technique (AE/MS) has emerged as one of the most important techniques in recent decades and has found wide applications in different fields. Extraction of seismic event with precise timing is the first step and also the foundation for processing AE/MS signals. However, this process remains a challenging task for most AE/MS applications. The process has generally been performed by human analysts. However, manual processing is time consuming and subjective. These challenges continue to provide motivation for the search for new and innovative ways to improve the signal processing needs of the AE/MS ...


Characterization Of Triboelectric Charging In Data Centers/Display Panel Manufactures, And Emi Visualization Based On Energy Parcels Method In High Speed Interconnections, Atieh Talebzadehghahroudi Jan 2018

Characterization Of Triboelectric Charging In Data Centers/Display Panel Manufactures, And Emi Visualization Based On Energy Parcels Method In High Speed Interconnections, Atieh Talebzadehghahroudi

Doctoral Dissertations

"This dissertation is composed of five papers. In the first three papers, triboelectric charging, which is the underlying cause of most electrostatic discharge (ESD), during daily human activities in data centers such as well-defined pattern walking, random walking, standing up from a chair, and taking off a sweater is investigated. Further, the effect of environmental condition (temperature and relative humidity), the footwear, and flooring material in building the static voltage and the discharge process are studied.

In the fourth paper, triboelectric charge generation on the glass is investigated during the glass transportation by roller conveyor systems in display manufacturing. The ...


Learning-Based Short-Time Prediction Of Photovoltaic Resources For Pre-Emptive Excursion Cancellation, Huaiqi Xie Jan 2018

Learning-Based Short-Time Prediction Of Photovoltaic Resources For Pre-Emptive Excursion Cancellation, Huaiqi Xie

Doctoral Dissertations

"There is a growing interest in using renewable energy resources (RES) such as wind, solar, geothermal and biomass in power systems. The main incentives for using renewable energy resources include the growing interest in sustainable and clean generation as well as reduced fuel cost. However, the challenge with using wind and solar resources is their indeterminacy which leads to voltage and frequency excursions. In this dissertation, first, the economic dispatch (ED) problem for a community microgrid is studied which explores a community energy market. As a result of this work, the importance of modeling and predicting renewable resources is understood ...


Investigation Of The Hydrodynamics And Scale-Up Of Advanced Triso Nuclear Fuel Manufacturing Using Sophisticated Measurement Techniques, Thaar M. Aljuwaya Jan 2018

Investigation Of The Hydrodynamics And Scale-Up Of Advanced Triso Nuclear Fuel Manufacturing Using Sophisticated Measurement Techniques, Thaar M. Aljuwaya

Doctoral Dissertations

"The successful performance and safety of the Very-High-Temperature Nuclear Reactors (VHTR) extremely depend on the quality of the TRISO nuclear fuel coated particles. However, the coating of the TRISO particles is delicate process and impacted by the hydrodynamics of spouted beds. Therefore, in this work, we applied advanced non-invasive measurement techniques which are gamma-ray computed tomography (CT) and radioactive particle tracking (RPT), to investigate foremost the local parameters to advance the fundamental understanding of the hydrodynamics and scale-up of gas-solid spouted beds. The CT technique has been applied to study the effects of particle density, particle size, bed size, and ...


The Effect Of Overloading On Reliability Of Wheel Loader Structural Components, Eric Raymond Achelpohl Jan 2018

The Effect Of Overloading On Reliability Of Wheel Loader Structural Components, Eric Raymond Achelpohl

Doctoral Dissertations

"This research attempts to provide a fundamental understanding into the relationship between the productivity of material handling equipment, specifically wheel loaders, and their ability to operate reliably when subjected to high overload conditions. The overall aim is to determine the effect of overloading the bucket on wheel loader reliability. The specific objectives of the research are to: 1) evaluate the effect of overloading the bucket on wheel loader productivity; 2) examine the effect of overloading the bucket on hydraulic pressures in the hoist cylinders (used as a proxy for forces on a wheel loader); and 3) investigate the effect of ...


Intersection Signal Control And Design For Improved Person Mobility And Air Quality In Urban Multimodal Transportation Systems, Farnoush Khalighi Jan 2018

Intersection Signal Control And Design For Improved Person Mobility And Air Quality In Urban Multimodal Transportation Systems, Farnoush Khalighi

Doctoral Dissertations

Alternative geometric designs (e.g. roundabouts) and multi-objective signal control strategies are promising measures to improve sustainability of traffic networks. However, roundabouts are mostly used because of their safety and operational advantages. There has been less attention to the environmental performance of roundabouts. Also, the existing studies have been mostly used through field measurements and current simulation models, which need high calibration efforts and they are not inclusive in terms of considering all influencing factors on vehicular emissions at roundabouts. Furthermore, the existing real-time signal control strategies do not account for the emission rates of different vehicle types (e.g ...


An Experimental Investigation Of The Influence Of Sampling On The Behavior Of Intermediate Soils, William Lukas Jan 2018

An Experimental Investigation Of The Influence Of Sampling On The Behavior Of Intermediate Soils, William Lukas

Doctoral Dissertations

Laboratory tests were performed in order to determine the effects of tube sampling disturbance on intermediate soils. Synthetic soils composed of Kaolin clay and silica silt, a reconstituted natural silt, and block sample specimens of a sensitive marine clay were tested. Tube sampling disturbance was simulated in a triaxial stress path system with bender element using the Ideal Sampling Approach prior to reconsolidation and undrained shear. ISA strain cycles of ±0.5, ±1 and ±3% were used to represent progressively greater degrees of disturbance. The influence of overconsolidation ratio (OCR) was explored by testing at OCRs of 1, 1.8 ...


Research On Additive Manufacturing Of Metallic Glass Alloy, Yiyu Shen Jan 2018

Research On Additive Manufacturing Of Metallic Glass Alloy, Yiyu Shen

Doctoral Dissertations

"The required rapid cooling has limited the dimension of the Bulk Metallic glasses (BMGs) produced by traditional method, and hence has seriously limited their applications, despite their remarkable mechanical properties. In this present project, a detailed study is conducted on the methodology and understanding of manufacturing large Zr- based metallic glass part by laser based additive manufacturing technology, which breaks the size limitation. The first research issue proposes and develops a new additive manufacturing technology, named Laser-Foil-Printing (LFP). Sheet foils of LM105 (Zr52.5Ti5Al10Ni14.6Cu17.9 (at. %)) metallic glass are used ...


Monitoring Of Hybrid Manufacturing Using Acoustic Emission Sensor, Haythem Gaja Jan 2018

Monitoring Of Hybrid Manufacturing Using Acoustic Emission Sensor, Haythem Gaja

Doctoral Dissertations

"The approach of hybrid manufacturing addressed in this research uses two manufacturing processes, one process builds a metal part using laser metal deposition, and the other process finishes the part using a milling machining. The ability to produce complete functioning parts in a short time with minimal cost and energy consumption has made hybrid manufacturing popular in many industries for parts repair and rapid prototyping. Monitoring of hybrid manufacturing processes has become popular because it increases the quality and accuracy of the parts produced and reduces both costs and production time. The goal of this work is to monitor the ...


Mitigation Of Environmental Hazards Of Sulfide Mineral Flotation With An Insight Into Froth Stability And Flotation Performance, Muhammad Badar Hayat Jan 2018

Mitigation Of Environmental Hazards Of Sulfide Mineral Flotation With An Insight Into Froth Stability And Flotation Performance, Muhammad Badar Hayat

Doctoral Dissertations

"Today's major challenges facing the flotation of sulfide minerals involve constant variability in the ore composition; environmental concerns; water scarcity and inefficient plant performance. The present work addresses these challenges faced by the flotation process of complex sulfide ore of Mississippi Valley type with an insight into the froth stability and the flotation performance. The first project in this study was aimed at finding the optimum conditions for the bulk flotation of galena (PbS) and chalcopyrite (CuFeS₂) through Response Surface Methodology (RSM). In the second project, an attempt was made to replace toxic sodium cyanide (NaCN) with the biodegradable ...


Behavior And Temporal-Based Effects Of Sustainable Self-Consolidating Concrete In Bridge Structures, Hayder Hussein Alghazali Jan 2018

Behavior And Temporal-Based Effects Of Sustainable Self-Consolidating Concrete In Bridge Structures, Hayder Hussein Alghazali

Doctoral Dissertations

"The main objective of this study was to investigate the performance of sustainable self-consolidating concrete (SCC) for highway bridge structures. Two types of concrete were utilized in this study: high volume fly ash-self consolidating concrete (HVFA-SCC) and high strength-self consolidating concrete (HS-SCC). This dissertation consists of two major parts: a laboratory study developing and investigating the overall performance of HVFA-SCC and a field study of time-dependent field-based behavior of HS-SCC in Bridge A7957 MO, USA. In the first part, an experimental program was conducted to develop a new class of SCC incorporating up to 70% cement replacement with fly ash ...


Strengthening Of Reinforced Masonry Walls Subjected To Out-Of-Plane Pseudo-Static Cyclic Load Using Advanced Composite, Zuhair Al-Jaberi Jan 2018

Strengthening Of Reinforced Masonry Walls Subjected To Out-Of-Plane Pseudo-Static Cyclic Load Using Advanced Composite, Zuhair Al-Jaberi

Doctoral Dissertations

"A number of researchers have conducted experimental tests on unreinforced masonry walls (URM) strengthened with advanced composite materials. Consequently, the strengthening design guidelines are limited in their scope to URM. This research aimed to investigate the behavior of reinforced masonry walls strengthened with advanced composite and subjected to out-of-plane pseudo-static cyclic load. Experimental and analytical studies were conducted to evaluate the performance of different techniques such as near surface mounted (NSM) and externally bonded (EB) fiber reinforced polymer (FRP) with epoxy resin, in addition to NSM with cementitious adhesive and fiber reinforced cementitious material (FRCM). The experimental part included three ...


Imaging And Mitigating Karst Features, Kenneth Joseph Bansah Jan 2018

Imaging And Mitigating Karst Features, Kenneth Joseph Bansah

Doctoral Dissertations

"Over the last three years, a comprehensive subsurface investigation that combines both conventional and geophysical techniques has been conducted near Springfield in southwest Missouri, United States. This study, which forms part of the comprehensive subsurface investigation, aimed to (1) image and characterize the subsurface, (2) map variations in engineering properties of soil/rock, (3) map variable depth to top of rock, (4) explore the utility of the geophysical techniques, (5) determine the factors contributing to karst processes, and (6) propose karst mitigation. Electrical resistivity tomography (ERT) and multichannel analysis of surface waves (MASW) were employed for the acquisition of subsurface ...


Service Response And Evaluation Of Prestressed Concrete Bridges Through Load Testing, Eli Saul Hernandez Ramos Jan 2018

Service Response And Evaluation Of Prestressed Concrete Bridges Through Load Testing, Eli Saul Hernandez Ramos

Doctoral Dissertations

"During the last two decades, self-consolidating concrete (SCC) has emerged as an alternative to produce structures with longer life expectancy. Despite the advantages that come with using SCC, there are some concerns related to its structural and serviceability response. The effect of the larger paste content and smaller coarse aggregate size is of particular interest because this combination may inhibit the development of the SCC's target mechanical properties. Field tests are an effective method to monitor the service response of infrastructure. In addition, field tests have largely confirmed reserves of strength capacity in existing bridges despite their visual condition ...


Guayule Plant Extracts As Binder Modifiers In Flexible (Asphalt) Pavement Mixtures, Steven Michael Lusher Jan 2018

Guayule Plant Extracts As Binder Modifiers In Flexible (Asphalt) Pavement Mixtures, Steven Michael Lusher

Doctoral Dissertations

"The guayule (pronounced, 'why-YOO-lee') plant is a woody perennial shrub that is native to areas of the southwestern United States and northern Mexico, and is a well-documented source of high-quality natural rubber. The U.S. needs a domestic source of natural rubber to allay concerns about its future availability. Cultivation of guayule in North America has been attempted many times since the late 19th century, and companies, including major tire manufacturers, are again investing in guayule research. However, full-scale commercialization of guayule rubber needs established markets for the two basic by-products of guayule rubber extraction: the plant resins (primarily non-rubber ...


Analysis Of Dc Microgrids As Stochastic Hybrid Systems, Jacob Andreas Mueller Jan 2018

Analysis Of Dc Microgrids As Stochastic Hybrid Systems, Jacob Andreas Mueller

Doctoral Dissertations

"A modeling framework for dc microgrids and distribution systems based on the dual active bridge (DAB) topology is presented. The purpose of this framework is to accurately characterize dynamic behavior of multi-converter systems as a function of exogenous load and source inputs. The base model is derived for deterministic inputs and then extended for the case of stochastic load behavior. At the core of the modeling framework is a large-signal DAB model that accurately describes the dynamics of both ac and dc state variables. This model addresses limitations of existing DAB converter models, which are not suitable for system-level analysis ...


On-Die Transient Event Sensors And System-Level Esd Testing, Abhishek Patnaik Jan 2018

On-Die Transient Event Sensors And System-Level Esd Testing, Abhishek Patnaik

Doctoral Dissertations

"System level electrostatic discharge (ESD) testing of electronic products is a critical part of product certification. Test methods were investigated to develop system level ESD simulation models to predict soft-failures in a system with multiple sensors. These methods rely completely on measurements. The model developed was valid only for the linear operation range of devices within the system. These methods were applied to a commercial product and used to rapidly determine when a soft failure would occur. Attaching cables and probes to determine stress voltages and currents within a system, as in the previous study, is time-consuming and can alter ...


Experimental And Numerical Investigation On Tar Production And Recycling In Fixed Bed Biomass Gasifiers, Jia Yu Jan 2018

Experimental And Numerical Investigation On Tar Production And Recycling In Fixed Bed Biomass Gasifiers, Jia Yu

Doctoral Dissertations

"Bioenergy has been utilized for domestic purposes since pre-recorded history and it catches the highlight in the recent decades because it naturally benefits the world climate and energy security. Gasification is one of the key technologies to efficiently and economically convert biomass into syngas and further into biofuels. Despite these outstanding advantages, biomass gasification suffers from the formation of unfavorable byproduct tar and the consequential tar elimination. Moreover, the collected tar is toxic and thus requires storage and strict deposit method to avoid environmental pollution.

To understand the mechanisms of biomass gasification and tar production, simulations with Aspen Plus were ...


Investigation Of Microstructure And Mechanical Properties By Direct Metal Deposition, Jingwei Zhang Jan 2018

Investigation Of Microstructure And Mechanical Properties By Direct Metal Deposition, Jingwei Zhang

Doctoral Dissertations

"Microstructure and properties of Direct Metal Deposition (DMD) parts are very crucial to meeting industrial requirements of parts quality. Prediction, and control of microstructure and mechanical properties have attracted much attention during conventional metal manufacturing process under different conditions. However, there is few investigations focused on microstructure simulation and mechanical properties control under different process parameters during DMD process. This dissertation is intended to develop a multiscale model to investigate Ti6Al4V grain structure development and explore Ti6Al4V based functionally graded material (FGM) deposit properties during DMD process. The first research topic is to investigate and develop a cellular automaton-finite element ...


Machine Learning Techniques Implementation In Power Optimization, Data Processing, And Bio-Medical Applications, Khalid Khairullah Mezied Al-Jabery Jan 2018

Machine Learning Techniques Implementation In Power Optimization, Data Processing, And Bio-Medical Applications, Khalid Khairullah Mezied Al-Jabery

Doctoral Dissertations

"The rapid progress and development in machine-learning algorithms becomes a key factor in determining the future of humanity. These algorithms and techniques were utilized to solve a wide spectrum of problems extended from data mining and knowledge discovery to unsupervised learning and optimization. This dissertation consists of two study areas. The first area investigates the use of reinforcement learning and adaptive critic design algorithms in the field of power grid control. The second area in this dissertation, consisting of three papers, focuses on developing and applying clustering algorithms on biomedical data. The first paper presents a novel modelling approach for ...


Integrated Study On The Applicability Of Co₂-Eor In Unconventional Liquids Rich Reservoirs, Dheiaa Khafief Khashan Alfarge Jan 2018

Integrated Study On The Applicability Of Co₂-Eor In Unconventional Liquids Rich Reservoirs, Dheiaa Khafief Khashan Alfarge

Doctoral Dissertations

"Unconventional Liquids Rich Reservoirs (ULR) such as Bakken, Niobrara, and Eagle Ford have become the main target for oil and gas investors as conventional formations started to deplete and diminish in number. These unconventional plays have a huge oil reserve; however, the predicted primary oil recovery is still low as an average of 7.5 %. Unconventional Improved Oil Recovery (UIOR) techniques are still a new concept in the oil industry because there is no commercial project for any IOR technique so far. Injecting carbon dioxide (CO₂) might be the most potential strategy to improve oil recovery in such complex plays ...


Electrodeposited Semiconductor Nanostructures & Epitaxial Thin Films For Flexible Electronics, Naveen Kumar Mahenderkar Jan 2018

Electrodeposited Semiconductor Nanostructures & Epitaxial Thin Films For Flexible Electronics, Naveen Kumar Mahenderkar

Doctoral Dissertations

"Single-crystal Si is the bedrock of semiconductor devices due to the high crystalline perfection which minimizes electron-hole recombination, and the dense native silicon oxide which minimizes surface states. To expand the palette of electronic materials beyond planar Si, an inexpensive source of highly ordered material is needed that can serve as an inert substrate for the epitaxial growth of grain boundary-free semiconductors, photonic materials, and superconductors. There is also a need for a simple, inexpensive, and scalable fabrication technique for the growth of semiconductor nanostructures and thin films. This dissertation focuses on the fabrication of semiconducting nanowires (polycrystalline Ge & epitaxial ...


The Separation Of Shear-Driven Liquid Films From A Sharp Corner, Zahra Sadeghizadeh Jan 2018

The Separation Of Shear-Driven Liquid Films From A Sharp Corner, Zahra Sadeghizadeh

Doctoral Dissertations

"The separation of shear-driven liquid films occurs in many engineering applications such as port fuel injected engines, demisters, and gas transfer lines. Despite the importance of this problem, the details of the interaction between operating parameters such as liquid flow rate, gas velocities and liquid film properties on the forces at the expanding corner are still not clear. To enhance the insight on the complicated interaction between the gas and liquid phases, the shear-driven liquid flow around a corner has been studied both experimentally and analytically in this work. The effect of the complex liquid film structure on liquid mass ...


Multi-Scale Investigation Of Microstructure, Fiber-Matrix Bond, And Mechanical Properties Of Ultra-High Performance Concrete, Zemei Wu Jan 2018

Multi-Scale Investigation Of Microstructure, Fiber-Matrix Bond, And Mechanical Properties Of Ultra-High Performance Concrete, Zemei Wu

Doctoral Dissertations

"The main objective of this study is to provide new insights into enhancing fiber-matrix bond and mechanical properties of ultra-high performance concrete (UHPC). Three main strategies were investigated: 1) use of supplementary cementitious materials; 2) use of nano-particles; and 3) use of deformed fibers. A multi-scale investigation involving the evaluation of non-fibrous UHPC mortar phase (matrix), fiber-matrix interface phase, and then UHPC composite material was undertaken to determine microstructural characteristics, fiber bond to matrix, and key mechanical properties of the UHPC matrix and UHPC. Test results indicate that the incorporation of 10%-20% silica fume effectively improved the fiber-matrix bond ...


The Significance Of Grouping And Missed Bubbles On Interfacial Area Concentration And Void Fraction, Chandller Stephen-Leslie Mills Jan 2018

The Significance Of Grouping And Missed Bubbles On Interfacial Area Concentration And Void Fraction, Chandller Stephen-Leslie Mills

Doctoral Dissertations

"The two-fluid model is used in nuclear reactor safety codes. Two of the important constitutive relations will be discussed in this study, the interfacial area concentration and void fraction. The Interfacial area concentration is directly affected by the number of bubbles and how these bubbles are categorized into groups. In this study, a new algorithm was implemented to account for trailing bubbles, bubbles with short response times, and the categorization of bubbles based upon diameter for all group 1 bubbles. The optical and conductivity probes were used to determine the void fraction and interfacial area concentration in a bubble column ...