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Masters Theses

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Full-Text Articles in Engineering

Managing Risks Of Market Price Uncertainty For A Microgrid Operation, Sriram Raghavan Jan 2016

Managing Risks Of Market Price Uncertainty For A Microgrid Operation, Sriram Raghavan

Masters Theses

"After deregulation of electricity in the United States, the day-ahead and real-time markets allow load serving entities and generation companies to bid and purchase/sell energy under the supervision of the independent system operator (ISO). The electricity market prices are inherently uncertain, and can be highly volatile. The main objective of this thesis is to hedge against the risk from the uncertainty of the market prices when purchasing/selling energy from/to the market. The energy manager can also schedule distributed generators (DGs) and storage of the microgrid to meet the demand, in addition to energy transactions from the market. The risk measure …


Carbon Transfer From Magnesia-Graphite Ladle Refractories To Ultra-Low Carbon Steel, Andrew Arthur Russo Jan 2016

Carbon Transfer From Magnesia-Graphite Ladle Refractories To Ultra-Low Carbon Steel, Andrew Arthur Russo

Masters Theses

"Ultra-low carbon steels are utilized in processes which require maximum ductility. Increases in interstitial carbon lower the ductility of steel; therefore, it is important to examine possible sources of carbon. The refractory ladle lining is one such source. Ladle refractories often contain graphite for its desirable thermal shock and slag corrosion resistance. This graphite is a possible source of carbon increase in ultra-low carbon steels. The goal of this research is to understand and evaluate the mechanisms by which carbon transfers to ultra-low carbon steel from magnesia-graphite ladle refractory.

Laboratory dip tests were performed in a vacuum induction furnace under …


Characterization Of Fracture Initiation In Non-Cylindrical Buckle Folds Using 3d Finite Element Analysis, Eli Jacob Steinbeck Jan 2016

Characterization Of Fracture Initiation In Non-Cylindrical Buckle Folds Using 3d Finite Element Analysis, Eli Jacob Steinbeck

Masters Theses

"The spatial distribution of fracture sets associated with buckle folds has been well documented in field studies. There are difficulties, however, in placing accurate constraints on the timing of the initiation of individual fracture sets during the deformation history of the fold under in-situ conditions. This study investigates specific conditions that give rise to the initiation of various fracture sets in the hinge and limb of a pericline, based on an analysis of the effective stress evolution during the processes of buckling and erosional unloading. A 3D finite element modeling approach is used to simulate the effective stress evolution in …


Artificial Neural Network Approach To Predict Blast-Induced Ground Vibration, Airblast And Rock Fragmentation, Raymond Ninnang Tiile Jan 2016

Artificial Neural Network Approach To Predict Blast-Induced Ground Vibration, Airblast And Rock Fragmentation, Raymond Ninnang Tiile

Masters Theses

"Blasting has been widely used as an economical and cheap way of rock breakage in mining and civil engineering applications. An optimal blast yields the best fragmentation in a safe, economic and environmentally friendly manner. The degree of fragmentation is vital as it determines to a large extent the utilization of equipment, productivity and mill throughput. Explosive energy, besides rock fragmentation, creates health and safety issues such as ground vibration, air blast, fly rock, and back breaks among others. As a result, the explosive energy impacts structures and buildings located in the vicinity of the blasting operation, and causes human …


Composite Model Representation For Computer Aided Design Of Functionally Gradient Materials, Fangquan Wang Jan 2016

Composite Model Representation For Computer Aided Design Of Functionally Gradient Materials, Fangquan Wang

Masters Theses

"Functionally Gradient Materials (FGMs) feature smooth transition from one material to another within a single object. FGMs modeling is considered to be one of the new challenges in Computer Aided Design (CAD) area. To overcome this challenge, this thesis presents a composite approach to model FGMs. The input in STL format can be meshed and voxelized in FGMs modeling system. The material composition in each voxel can be generated from multiple different types of control features. And LTI filters including Gaussian Filter and Average Filter are applied to blur default material features in order to generate FGMs inside models. The …


De-Embedding Method For Electrical Response Extraction Of Through-Silicon Via (Tsv) In Silicon Interposer Technology And Signal Integrity Performance Comparison With Embedded Multi-Die Interconnect Bridge (Emib) Technology, Qian Wang Jan 2016

De-Embedding Method For Electrical Response Extraction Of Through-Silicon Via (Tsv) In Silicon Interposer Technology And Signal Integrity Performance Comparison With Embedded Multi-Die Interconnect Bridge (Emib) Technology, Qian Wang

Masters Theses

"Traditional two-dimensional system-in-package (2D SiP) can no longer support the scaling of size, power, bandwidth, and cost at the same rate required by Moore's Law. Three-dimensional integrated circuits (3D-ICs), 2.5D silicon interposer technology in which through silicon vias are widely used, are implemented to meet these challenges. Embedded multi-die interconnect bridge (EMIB) technology are proposed as well.

In Section 1, a novel de-embedding method is proposed for TSV characterization by using a set of simple yet efficient test patterns. Full wave models and corresponding equivalent circuits are provided to explain the electrical performance of the test patterns clearly. Furthermore, broadband …


Engine Sound Simulation And Generation In Driving Simulator, Shuang Wu Jan 2016

Engine Sound Simulation And Generation In Driving Simulator, Shuang Wu

Masters Theses

"Simulating a driving environment that provides engine sound as auditory feedback to the driver is a challenging task due to the complexity of engine sound, a wide range of operating speeds, and repeated sound clicking during playback. This thesis describes a method of engine sound simulation and generation for a driving simulator. By analyzing sample sounds, spectral modeling synthesis was used to decompose the sound samples into deterministic and stochastic components. Then, the modeled deterministic and stochastic signals were employed to resynthesize the sounds. To represent engine sounds not available in the recorded database, sound interpolation was applied to two …


Fluid Flow Through Deformation Band, Huining Zhang Jan 2016

Fluid Flow Through Deformation Band, Huining Zhang

Masters Theses

"Cataclastic deformation bands, which are common in porous sandstone, have the potential to restrict fluid flow. Geological studies have shown that permeability of deformation band shear zones can be one to five orders of magnitude less than for the sandstone host rock. However, recent studies based on simplified analytical estimates have shown that fluid flow in jointed deformation bands may not be retarded since joints play an important role in conducting fluids. In this study, 2 dimensional finite element analysis (FEA) is used to simulate the total discharge flow rate through jointed deformations. Variations of single planar and conjugate jointed …


A Linear Matrix Inequality-Based Approach For The Computation Of Actuator Bandwidth Limits In Adaptive Control, Daniel Robert Wagner Jan 2016

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 …


A Statistical Analysis Of A 4.5 Mw Solar Energy Center, Archit Patnaik Jan 2016

A Statistical Analysis Of A 4.5 Mw Solar Energy Center, Archit Patnaik

Masters Theses

"This project helps a regional utility evaluate the performance of their 4.5 MW photovoltaic plant. The performance evaluation consists of characterizing the peak and average power and energy output of the plant over varying time periods. A characterization of the output power drops, or dips, is done by performing a statistical analysis of the photovoltaic plant output data. Dips are characterized by dip frequency, depth of dip, energy loss by dip, and dip duration. The results of this study will help the utility to select appropriate voltage regulating equipment on the basis of dip characteristics, and thus, optimize the performance …


Conceptual Parameters Necessary For Modeling Wettability Alteration In An Enhanced Smart Brine-Chalk System, Ahmed Abdulkareem Hussein Albahrani Jan 2016

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 And Analysis Of An Axisymmetric Aerospike Supersonic Micro-Nozzle For A Refrigerant-Based Cold-Gas Propulsion System For Small Satellites, Abdalla Ali Bani Jan 2016

Design And Analysis Of An Axisymmetric Aerospike Supersonic Micro-Nozzle For A Refrigerant-Based Cold-Gas Propulsion System For Small Satellites, Abdalla Ali Bani

Masters Theses

"The cold-gas propulsion system being developed by M-SAT requires improvements to its original nozzle design. This study documents the research, design, and analysis of a supersonic plug nozzle concept that could be integrated to the refrigerant-based cold-gas propulsion system to possibly improve its performance. As documented in this thesis, CFD analysis showed that the outlined nozzle design method resulted in a feasible nozzle concept that has the ability to out-perform a conventional nozzle of the same area ratio. The flow-fields and thrust of the aerospike nozzle, for the full and truncated nozzles, were investigated. The purpose of this study is …


Exploring Reservoir Connectivity With Production Data: Two New Methods And A New Technique, Ghazwan Faisal Jasim Al-Khmaysawee Jan 2016

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 …


Voltage Control In A Distribution System Using Active Power Loads, Mounika Chava Jan 2016

Voltage Control In A Distribution System Using Active Power Loads, Mounika Chava

Masters Theses

"High penetration of renewable energy resources such as rooftop solar photovoltaic (PV) systems is exacerbating violations of the voltage limits in power distribution networks. Existing solutions to these over-/under-voltage issues include tap-changing transformers and shunt capacitors. However, tap changers only allow voltage changes in discrete steps and shunt capacitors cannot handle over-voltage situations. To overcome these problems, this thesis proposes voltage control in a distribution system by adjusting active power loads. The proposed solution can be used for both under- and over-voltage cases at any levels of voltage adjustment. First, the active power that needs to be adjusted at selected …


Design, Scale-Up, Six Sigma In Processing Different Feedstocks In A Fixed Bed Downdraft Biomass Gasifier, Sai Chandra Teja Boravelli Jan 2016

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 …


An Investigation Of Plugging And Increasing Oil Recovery In Sandstone Porous Media By Micrometer-Size Particle Gel, Haifeng Ding Jan 2016

An Investigation Of Plugging And Increasing Oil Recovery In Sandstone Porous Media By Micrometer-Size Particle Gel, Haifeng Ding

Masters Theses

"Micrometer-size particle gel (microgel) has been developed and successfully applied to improve conformance in mature reservoirs. However, quite few researches have been published to address on their effect on oil recovery and rock permeability modification.

This work conducted a series of core flooding experiments to investigate the injectivity, plugging efficiency and improving oil recovery potentials of a couple of microgels synthesized in our lab.

First, this work studied the impact of permeability and crosslinker concentration on PAM type microgel treatment. Results shows that microgel treatment would have a less plugging efficiency in lower permeability rocks, which could be caused by …


Analysis Of Va Sacramento Medical Center Capacity Using Discrete Event Simulation, Tatiana Alejandra Cardona Jan 2016

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 …


Sensitivity Analysis Of Geomechanical Parameters In A Two-Way Coupling Reservoir Simulation, Hector Gabriel Donoso Jan 2016

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 …


Addressing The Influence Of Carbon Monoxide On The Behavior Of An Hcci Engine, Allen Charles Ernst Jan 2016

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 …


Design Methodology For Behavioral Surface Roughness Modeling And High-Speed Test Board Design, Xinyao Guo Jan 2016

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 …


Characterization Of Electric Solid Propellant Pulsed Microthrusters, Matthew Scott Glascock Jan 2016

Characterization Of Electric Solid Propellant Pulsed Microthrusters, Matthew Scott Glascock

Masters Theses

"Electric solid propellants are an attractive option for space propulsion because they are ignited by applied electric power only. In this work, the behavior of pulsed microthruster devices utilizing such a material is investigated. These devices are similar in function and operation to the pulsed plasma thruster, which typically uses Teflon as propellant. A Faraday probe, Langmuir triple probe, residual gas analyzer, pendulum thrust stand and high speed camera are utilized as diagnostic devices. These thrusters are made in batches, of which a few devices were tested experimentally in vacuum environments. Results indicate a plume electron temperature of about 1.7 …


Impact Of Repeated Cyclic Production Scheme On Eur In Low-Permeability Reservoirs, Samarth Gupte Jan 2016

Impact Of Repeated Cyclic Production Scheme On Eur In Low-Permeability Reservoirs, Samarth Gupte

Masters Theses

"Productivity in low-permeability reservoirs declines quickly compared to conventional reservoirs. These tight reservoirs have very high initial oil production rates but as soon as the oil near the fractured area is recovered, the production declines rapidly making economic oil and gas production a challenge for the industry. This study investigates the impact of repeated shut-in/production cycles on the ultimate recovery of oil in such environments.

A reservoir model with multiple fractured horizontal well having 30 transverse fractures is created using CMG. Reservoir permeability is varied over the range of 0.000001 md to 10 md and shut-in/production cycles of 2-weeks, 1-month, …


Accurate Imepdance Measurement Of O Clip And Near Field Coupling Estimation Using Equivalent Dipole Moment Model, Qiaolei Huang Jan 2016

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 …


Single Phase Gas Flow Response Of Fractured Horizontal And Vertical Wells To Repeated Production, Divya Kandlakunta Jan 2016

Single Phase Gas Flow Response Of Fractured Horizontal And Vertical Wells To Repeated Production, Divya Kandlakunta

Masters Theses

"Historically, the conventional approach to well production has been to produce continuously, minimizing interruptions to flow insofar as possible. Yet some operators have observed improved well flow rates and ultimate recovery after a significant well shut-in periods. These production increases have not been documented. This study investigates the production impact of cyclic production/shut-in on fractured vertical and horizontal gas well performance.

A numerical reservoir model in Stimplan software was used to model production in fracture stimulated vertical and horizontal gas wells. Reservoir permeability is varied over a range of 0.0001 md to 1 md, and the shut-in period was varied …


Studies On Flocculation Of Fine Mineral Tailings Using Novel Polyacrylamide Based Polymer, Simin Khatibi Jan 2016

Studies On Flocculation Of Fine Mineral Tailings Using Novel Polyacrylamide Based Polymer, Simin Khatibi

Masters Theses

"One of the important features in managing or treating sulfide fine tailings is separating solids from liquid by settling test. This thesis presents results of studied conducted on flocculation of Kaolin suspensions (a model tailings) and sulfide mineral tailings. Two polymers (PAM and Al-PAM) were tested as flocculants. The zeta potential value of slurries was measured by Nano Zetasizer device.

Al-PAM was found to be more effective for flocculation of kaolinite samples and also sulfide samples while PAM with used concentration was not. This study represents the power of flocculation as a possible solution to deal with industrial tailings"--Abstract, page …


Bioresponsive Polymer Coating On Nanoparticles, Tunyaboon Laemthong Jan 2016

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 Jan 2016

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 …


Construction And Validation Of Tl-Ipm Generator, Jamaluddin Mohammad Jan 2016

Construction And Validation Of Tl-Ipm Generator, Jamaluddin Mohammad

Masters Theses

"Hydrokinetic energy is one of the potential sources of energy that can be extracted and converted to electrical energy using linear generator. This work discusses about construction and validation of tubular linear internal permanent magnet (TL-IPM) generator, a kind of linear generator. The generator could produce electricity by converting linear motion generated from vortex induced vibrations induced due from a flowing fluid, such as a river. A simulation model of the generator is created using Ansoft's Maxwell software, which uses finite element analysis to perform electromagnetic analysis of the generator. Then a practical generator was built and tested. The results …


Computational Fluid Dynamics (Cfd) Simulations Of Molten Steel Flow Patterns And Particle-Wall Adhesion In Continuous Casting Of Steels, Mahdi Mohammadi-Ghaleni Jan 2016

Computational Fluid Dynamics (Cfd) Simulations Of Molten Steel Flow Patterns And Particle-Wall Adhesion In Continuous Casting Of Steels, Mahdi Mohammadi-Ghaleni

Masters Theses

"In this research, the measurements of clog deposit thickness on the interior surfaces of a continuous casting nozzle were compared with Computational Fluid Dynamics (CFD) predictions of melt flow patterns and particle-wall interactions to identify the mechanisms of nozzle clogging. A hybrid turbulent approach, Detached Eddy Simulation (DES), was configured to simulate both turbulent structures and particle-wall interactions inside the nozzle accurately. For experimental measurements of nozzle clogging, a nozzle received from industry was encased in epoxy and carefully sectioned to allow measurement of the deposit thickness on the internal surfaces of the nozzle. CFD simulations of melt flow patterns …


Hidden Markov Model Based Non-Intrusive Load Monitoring Using Active And Reactive Power Consumption, Paulomi Nandy Jan 2016

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 …