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A Linear Matrix Inequality-Based Approach For The Computation Of Actuator Bandwidth Limits In Adaptive Control, Daniel Robert Wagner

Masters Theses

"Linear matrix inequalities and convex optimization techniques have become popular tools to solve nontrivial problems in the field of adaptive control. Specifically, the stability of adaptive control laws in the presence of actuator dynamics remains as an important open control problem. In this thesis, we present a linear matrix inequalities-based hedging approach and evaluate it for model reference adaptive control of an uncertain dynamical system in the presence of actuator dynamics. The ideal reference dynamics are modified such that the hedging approach allows the correct adaptation without being hindered by the presence of actuator dynamics. The hedging approach is first …

Conceptual Parameters Necessary For Modeling Wettability Alteration In An Enhanced Smart Brine-Chalk System, Ahmed Abdulkareem Hussein Albahrani

Masters Theses

"Achieving higher recovery of oil from proven carbonate reserves around the world is not an easy task. One promising new method, especially for carbonate reservoirs, is the use of "Smart Water" technology, which is an injection water with carefully determined, optimal ionic composition and salinity. Recent experiments have shown good recovery results, but the mechanism of wettability alteration by this fluid are still not well understood. The goal of this study is to review the high and optimal salinity and ionic composition literature plus perform dimensional analysis of key variables in order to shed light on the physical and chemical …

Design, Scale-Up, Six Sigma In Processing Different Feedstocks In A Fixed Bed Downdraft Biomass Gasifier, Sai Chandra Teja Boravelli

Masters Theses

"This thesis mainly focuses on design and process development of a downdraft biomass gasification processes. The objective is to develop a gasifier and process of gasification for a continuous steady state process. A lab scale downdraft gasifier was designed to develop the process and obtain optimum operating procedure.

Sustainable and dependable sources such as biomass are potential sources of renewable energy and have a reasonable motivation to be used in developing a small scale energy production plant for countries such as Canada where wood stocks are more reliable sources than fossil fuels. This thesis addresses the process of thermal conversion …

Analysis Of Va Sacramento Medical Center Capacity Using Discrete Event Simulation, Tatiana Alejandra Cardona

Masters Theses

"The development of simulation models continues to provide effective solutions to a wide range of problems in healthcare systems. In the research presented within this thesis is the development of a representative and validated discrete event simulation model for the purpose of evaluating additional capacity. The study consists of a detailed exploratory analysis, verification and validation tests of the simulation results, and a thorough design of experiments. The exploratory analysis consisted of developing simulation models that provide similar characteristics found in the data. The design of experiments consisted of generating scenarios of various bed additions in the hospital units of …

Exploring Reservoir Connectivity With Production Data: Two New Methods And A New Technique, Ghazwan Faisal Jasim Al-Khmaysawee

Masters Theses

"This study presents two new, simple methods to explore reservoir connectivity, which has a significant impact on field development strategy. Identifying reservoir connectivity during primary depletion plays an important role in achieving the most cost-effective and highest production possible. It is also very important in future secondary and tertiary oil recovery, particularly when costs dictate a limited number of wells such as those in deepwater environments.

The presented methods are reciprocal-productivity index versus total field material-balance time trend lines and reciprocal-productivity index versus time trend lines. Those two methods are quick, simple, inexpensive, and only need rate and pressure data …

Addressing The Influence Of Carbon Monoxide On The Behavior Of An Hcci Engine, Allen Charles Ernst

Masters Theses

"Homogeneous Charge Compression Ignition (HCCI) may be the next leap of improvement to internal combustion engines due to its decreased emissions and improved engine efficiencies. However, such a jump possesses challenges owing to its strict reliance on the inherent physics that dictate start of combustion and limit the reach of stable operation. This work investigates the role and fundamental influence of carbon monoxide on the cycle-to-cycle combustion dynamics present in the region of incomplete combustion that frames the limited HCCI operating region. An improved understanding will open doors to enhanced control methodologies and an expanded stable operating envelope. A constant …

Sensitivity Analysis Of Geomechanical Parameters In A Two-Way Coupling Reservoir Simulation, Hector Gabriel Donoso

Masters Theses

"Currently reservoir simulators model geomechanical effects such as compaction, subsidence, fault reactivation, breach of the seal integrity, etc. using only the rock compressibility to change the pore volume. However, rock compressibility as a scalar quantity is unfit to represent the true rock mechanics in the reservoir. In order to accurately represent geomechanical effects in a reservoir simulation, a two-way coupling simulation of the stress analyzer and the reservoir simulator was done. Based on the poroelasticity theory during the production or depletion of the reservoir the porosity and permeability changed due to the stress or pore pressure changes.

A sensitivity analysis …

Design Methodology For Behavioral Surface Roughness Modeling And High-Speed Test Board Design, Xinyao Guo

Masters Theses

"A behavioral model is introduced, which can predict low-loss and low surface roughness transmission line time- and frequency- domain performances. High data rates push for better performance of PCB transmission lines. However, the roughness of copper foil has a considerable impact on the signal integrity performance of transmission lines at high data rates and long propagation distance. Existing models for low-loss transmission line surface roughness are inadequate. A new behavioral model to represent the surface roughness has been developed. The model is applied in the design process by adding a dispersive term to the bulk dielectric permittivity to represent the …

Accurate Imepdance Measurement Of O Clip And Near Field Coupling Estimation Using Equivalent Dipole Moment Model, Qiaolei Huang

Masters Theses

"As cellphones and electronic devices moves towards higher date rates yet smaller form factor, designer face more electromagnetic interference (EMI) and radio frequency interference (RFI) problems. In order to better guide the early design; designers want to know the exact electrical performance of small components, coupling estimation between components.

In Section 1, a de-embedding method is proposed to measure the impedance of an innovative O-shape spring contact, for frequency up to 30 GHz. The measurements are performed under the same condition when it's actually used in cellphones. De-embedding method will be applied to remove the fixture effects of the measurement …

Bioresponsive Polymer Coating On Nanoparticles, Tunyaboon Laemthong

Masters Theses

"Nanotechnology incorporated with molecular biology became a promising way to treat cancer. The size of nanoparticles enables them to overcome the side effects noticed in cancer treatment like chemotherapy and surgery. Various types and shapes of nanoparticles have been synthesized and used in drug delivery to tumor sites. However, one of problems of using these nanoparticles is the aggregation after injecting them into human body due to flow rate of bloodstream. The coagulation and aggregation will result in clogging blood vessel and lower therapeutic efficacy.

In this thesis, a solution to the aggregation problem was proposed, which is coating biopolymer …

Study And Development Of Robust Preformed Particle Gels For Conformance Control, Yifu Long

Masters Theses

"To improve the oil recovery of mature reservoirs, technologies referring to conformance control have been widely developed and implemented. Among various technologies, preformed particle gel (PPG) treatment has attracted increasing attentions. PPGs, as a kind of deformable plyometric superabsorbent, could be pumped through injection wells as plugging agents to block the fracture or high-permeability zone in a reservoir.

In decade usage of PPGs, an intensively employed material is poly(acrylamide) (PAM) based hydrogel. However, conventional PAM gel did reveal deficient in formidable conditions, such as formations with high temperature and high salinity. Therefore, a novel PPG based on starch-grafting-poly(acrylamide)/nano-composite (SAC) hydrogel …

Hidden Markov Model Based Non-Intrusive Load Monitoring Using Active And Reactive Power Consumption, Paulomi Nandy

Masters Theses

"This work presents a residential appliance disaggregation technique to help achieve the fundamental goal in Non-Intrusive Load Monitoring (NILM) problem i.e. simple breakdown of energy consumption based on the appliance type in a household. The appliances are modeled using Hidden Markov Model by utilizing both their active and reactive power consumption data. The data was recorded by attaching Power Standards Lab PQube measurement device to the appliances. Granularity of the power readings of the disaggregated appliance matches with that of the reading collected for individual device. The accuracy of the model is compared with other models developed using only active …

Surface Modification Of Tin Oxide Nanoparticles By Atomic Layer Deposition For Enhanced Electrochemical Performance, Sai Abhishek Palaparty

Masters Theses

"Atomic Layer Deposition is a robust technique used to deposit high quality, conformal, and size-tunable ultrathin films on a substrate. This technique can be used to coat protective films on battery anode and cathode materials for enhanced performance. In the case of cathodes, the ultrathin film provides a protective barrier preventing cationic dissolution. In the case of anodes, the film acts as a supporting matrix reducing strain caused by volume expansions. In these study, we use this technique to coat an optimally thick conductive iron oxide film on tin oxide particles to improve its electrochemical performance at high current densities …

Hydrodynamic Of A Co-Current Gas Liquid Upflow In A Moving Packed Bed Reactor With Porous Catalysts, Ali Jabbar Toukan

Masters Theses

"In this study, the hydrodynamic, i.e. flow regime identification, line average liquid holdup, and the internal liquid holdup of a co-current moving packed bed reactor were studied. For the sake of hydrodynamics study, moving bed reactor is investigated as two-phase upflow packed bed reactor. Scaled down configuration was used to simulate of the moving bed reactors utilized in the industrial process. First, line average liquid holdup is measured with different geometrical configurations covering empty, dry, wet, and packed column under flowrates operation conditions. A new methodology has been developed to determine the line average liquid holdup for a porous catalyst. …

Computational Fluid Dynamic Analysis In High Permeability Hydraulic Fractured Horizontal Gas Wells, Hrithu Vasudevan

Masters Theses

"Hydraulic fracturing of horizontal wells in unconventional reservoirs has become the dominant type of well completion performed in the United States. In very low permeability reservoirs (~.00001-.0001 mD), the wellbore is aligned with the minimum horizontal stress, and the completion includes multiple transverse fractures. These fractures may be placed with either open hole sleeve type completion systems (OHMS), or cased hole plug and perf systems (P-n-P). In slightly higher permeability reservoirs (1 to 10 mD) multiple longitudinal fractures have been found to be preferred to completions with transverse fractures.

This study presents an evaluation of gas well productivity for both …

Development And Testing Of A Fracture Energy-Based Model Of Explosive Asteroid Deflection, James A. Veerkamp

Masters Theses

"While asteroid deflection has been studied for the past half century, efforts have generally been directed towards methods that attempt to minimize disruption of the rock body. In order to widen the base of research, a fracture energy-based model of asteroid fragmentation was developed and applied to both asteroid scale and lab testable scale cases. Modeling of the orbital case suggests the capability to deflect a 100 meter diameter asteroid on a 10 year timescale. The model's predicted energy transfer is then compared to laboratory testing using a ballistic pendulum. The results of this testing suggest that the model as …

Data Analysis For Driving Pattern Identification And Driver's Behavior Modeling In A Freeway Work Zone, Hari Narayanan Vijaya Raghavan Nadathur

Masters Theses

"A variety of methods are used by Departments of Transportation (DOT) for informing drivers about upcoming work zones. One such method is work zone signage configuration. Signage plays an important role in work zones to provide guidance to drivers when conditions on the road vary from normal. Therefore, it is necessary to evaluate the effectiveness of different configurations, by law, before implementation of new signage designs that deviate from the national standards.

The Manual on Uniform Traffic Control Devices (MUTCD) is a compilation of national standards for all traffic control devices, including road markings, highway signs, and traffic signals. In …

Correlation Anaylsis Of Magnesite Dissolution Rate And Magnesite Spatial Distribution, Yao Wang

Masters Theses

"This thesis presents a correlation analysis of the spatial distribution and permeability of magnesite dissolution and focuses on its overall rate and average porosity. Magnesite dissolution is affected by several aspects.

A reservoir's large spatial distribution can make capturing the magnesite dissolution difficult, so in this study, a variogram was built in Petrel using a percentage variation of magnesite and sand. The variogram also handles different major and minor directions in anisotropy. After building the magnesite model, simulation of magnesite dissolution was achieved in Cruch Flow to get the magnesite dissolution rate and average porosity.

For correlation analysis, a regression …

Design Of An Adaptive Force And Stiffness Controlled Compliant Device For Robotic Polishing, Mohammad Masud Parvez

Masters Theses

"Polishing is a repetitive task done in an unhealthy environment. Often more than half of the manufacturing time is required to polish a die. The manual polishing process is a tedious work actively rely on a skilled human worker. Industrial Robot has replaced the human in performing these tasks. For robotic polishing to control the polishing force, an active compliant device is used. Due to the compressibility of air, a pneumatic system is preferred as the actuator of the device. The force of the actuator is controlled by regulating air pressure in both chambers of the cylinder. However, to improve …

A Comprehensive Study Of Lost Circulation With Application In The South Rumaila Field, Iraq, Abo Taleb Tuama Al-Hameedi

Masters Theses

“Drilling mud losses and problems associated with lost circulation while drilling account for a major expense in drilling oil and gas wells. By industry estimates, more than 2 billion USD is spent annually to combat and mitigate this problem (Ali et al., 2015).

The South Rumaila field in Iraq is one of the largest oilfields in the world. Wells drilled in this field are highly susceptible to lost circulation problems when drilling through the Dammam, Hartha and Shuaiba formations. Lost circulation events range from seepage losses to complete loss of the borehole and are a critical issue in field development. …

Behavior Of Hollow-Core Composite Columns Under Torsion Loading, Sujith Anumolu

Masters Theses

"The effect of torsional loads could be significant along with axial and flexural loads on bridge columns during earthquake excitations. The present study presents the torsional behavior of hollow-core steel-concrete-steel columns (HC-SCS) and hollow-core fiber reinforced polymer-concrete-steel columns (HC-FCS). The HC-SCS comprises of sandwiched concrete shell between two steel tubes whereas in HC-FCS column, the outer steel tube of HC-SCS column was replaced by the FRP tube. Both columns have stay-in place permanent form-work to the concrete shell in the form of outer and inner tubes. The steel tubes serve as longitudinal and shear reinforcement to the column. Finite element …

Effect Of Reservoirs Heterogeneity On Injection Pressure And Placement Of Preformed Particle Gel For Conformance Control, Ze Wang

Masters Theses

"Preformed particle gels (PPG) have been successfully applied as a plugging agent for plugging fractures and then divert displacing fluid into poorly swept zones. However, PPG propagation and plugging mechanisms through open fractures have not been studied thoroughly.

This work investigated the influence of some factors (particle size, brine concentration, heterogeneity, and brine salinity) on gel injectivity, plugging performance for water flow through open fractures. Five-foot tubes were used to mimic open fractures. Three models were designed to conduct the work, including (1) single fracture with uniform fracture width, (2) single fracture with different widths, and (3) two parallel fractures …

Spatiotemporal Analysis Of Gene Flow Patterns Among Woodland Salamander Populations Inhabitating Contrasting Landscapes, Alexander C. Cameron

Masters Theses

Dispersal is a fundamental evolutionary process that serves as a mechanism by which local populations remain connected through space. Habitat loss and fragmentation remain widespread threats to biodiversity globally, and therefore it is imperative to understand how dispersal patterns are affected by anthropogenic modifications of the environment. Using a panel of 10 novel microsatellite loci, I estimated gene flow patterns over historical and contemporary timescales among populations of Eastern Red-backed Salamanders (Plethodon cinereus) in a previously unstudied portion of the species range. Four focal populations reside within a highly fragmented urban center whereas the remaining four focal populations persist in …

Material Properties Characterization For Multilayer Pcb And Peec Macromodels For Above Plane Decoupling Capacitors, Xiang Fang

Masters Theses

"Accurate frequency-dependent dielectric properties are important for accurate modelling of signal and power integrity problems. And decoupling capacitors perform an important function in the impedance reduction of power distribution systems. Hence, precise dielectric properties and micromodels for decoupling capacitors are the key parts for the signal and power integrity design.

In Section 1, the existing method for extracting dielectric properties from fabricated multilayer printed circuit boards based on the measured electrical property of fabricated transmission lines is introduced and validated using simulations. And the potential errors in the procedure are discussed. After that Djordjevic-Sarkar causal dielectric model for dielectric properties …

Oxidative Dehydrogenation Of Light Alkanes With Carbon Dioxide, Marktus A. Atanga

Masters Theses

”Most experts studying the global ecosystem and climate suggest that rising anthropogenic CO₂ emissions have contributed to significant global climate change in the last half-century. The development of effective strategies that convert CO₂ into energy, fuels, and chemicals are greatly preferable to oceanic or geologic sequestration options because they offer the potential to create new commercially-viable products from renewable carbon feedstock. On the other hand, the selective oxidative dehydrogenation of light alkanes (C₂-C₄) to corresponding olefins, methane reforming, and methane coupling are the major challenges for producing valuable and versatile feedstocks. The oxidative dehydrogenation …

Thresholding Techniques For Discrimination Of Seborrheic Keratosis From Melanoma In Dermoscopy Images, Pramada Kishtagari

Masters Theses

“Malignant melanoma is a very deadly form of skin cancer which has claimed many lives over the past few years. If detected early this can be cured, hence early detection of malignant melanoma is essential. Unfortunately melanoma is mimicked by seborrheic keratosis, a benign skin cancer. Identifying malignant melanoma as seborrheic keratosis using clinical diagnosis can prove fatal to the patient. To prevent such errors, dermoscopy, a common non-invasive skin imaging technique, is used which improves the diagnosis of these pigmented lesions by visualizing the morphological structures. This study proposes an automatic method by applying image processing techniques to aid …

Evaluation Of Highly Viscous Polymeric Fluids And Recrosslinked Degraded Gel, Danlu Zhang

Masters Theses

”This work presents the evaluations of two products. One can be used for hydraulic fracturing to achieve viscosity stable under high shear rate, and the other is potential to be applied to enhance oil recovery from mature oilfield.

The first experiment is to synthesize and evaluate a new polymeric fracturing fluid that can resist high shear rate of 511^-1 with favorable viscosity. Zirconium crosslinked fracturing fluids are lack of self-healing ability after shearing, and the difficulties still exist in maintaining viscous with lower polymer content exposed to high shearing conditions, therefore, the research is trying to develop a new …

Gravity And Magnetic Investigations Of The North-Eastern Kansas Section Of The Midcontinent Rift System, Ozgun Kamil Sahin

Masters Theses

"The Midcontinent Rift System (MRS) is a major Precambrian magmatic province on the North American continent. It formed when the North American craton began to split apart during the Mesoproterozoic era (1,100 Ma). As a result of the extension and possibly the effects of a rising mantle plume, a thick layer of basalt and numerous reverse and normal faults were formed. The basalt layer is buried below sedimentary formations and makes it difficult for seismic techniques to image. On the other hand, gravity and magnetic methods can be utilized for focused depths, and the basalt layer of the system can …

Factors Influencing The Adoption Of Smart Wearable Devices, Apurva Adapa

Masters Theses

"This study aims to examine the factors and issues in adoption of smart wearable devices. Wearable devices have many functions to offer which make them very useful in our daily lives. However, factors influencing the adoption of these devices are not well understood. This research explores the inhibiting and contributing factors influencing the adoption of wearable devices by employing the laddering approach. Qualitative data were collected through in-depth interviews using the laddering technique in order to understand these factors. Wearable devices that were examined include the Smart Glass (Google Glass) and the Smart Watch (Sony Smart Watch 3). After the …

Aspen Simulation Of Oil Shale And Biomass Process, Anand Alembath

Masters Theses

"This thesis focuses on design and analysis of two major chemical processes using computer simulation which performs a steady state computation. The objective is to design processes using Aspen simulation to establish optimum operating conditions by performing various simulation runs which are challenging to execute at lab scale.

Increasing energy needs and decline of global oil prices has shifted our focus on commercially developing unconventional and renewable resources. Commercialization of any process relies on developing a process model that identifies different process parameters by performing a steady state mass and heat balance. Aspen simulation is considered an effective process modeling …