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Articles 2011 - 2040 of 7906
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Reprocessing And Structural Interpretation Of Multichannel Seismic Reflection Data From Penobscot, Nova Scotia, Fulya Gizem Yagci
Reprocessing And Structural Interpretation Of Multichannel Seismic Reflection Data From Penobscot, Nova Scotia, Fulya Gizem Yagci
Masters Theses
"Penobscot area is located in the Scotian Basin, which was occurred as a result of extension in the eastern North America border. 2-D data set that was utilized for the study consists of three multichannel seismic profiles that were collected from Penobscot Parcel 8. The main purpose of the study was to enhance signal-to-noise ratio of the seismic reflection sections suppressing high frequency noise and multiples, and removing diffractions. In addition, while the resolution of the sections were enhanced, determining the correct processing techniques and parameters for better results was the another important criteria.
The processing steps included deconvolution, minimum …
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 …
Study On The Applicability Of Relative Permeability Modifiers For Water Shutoff Using Numerical Simulation, Dheiaa Khafief Khashan Alfarge
Study On The Applicability Of Relative Permeability Modifiers For Water Shutoff Using Numerical Simulation, Dheiaa Khafief Khashan Alfarge
Masters Theses
"Water production is a challenging problem to be controlled during hydrocarbon-reservoirs production life. Disproportionate Permeability Reduction (DPR) is often used as water shutoff treatment in production wells when other conventional solutions like mechanical isolations are difficult to perform. This study applied numerical simulation methods to diagnose the factors impacting DPR treatment success on macroscopic level and to see when, where and at which conditions DPR treatment can give best results.
This work indicated that the following points should be considered before DPR treatment is executed in any reservoir to get a successful treatment. Firstly, this research explored that DPR performance …
Prediction Of Surface Roughness In Abrasive Waterjet Cutting Of Graphite Composite Using Response Surface Methodology, Prabhakar Bala
Prediction Of Surface Roughness In Abrasive Waterjet Cutting Of Graphite Composite Using Response Surface Methodology, Prabhakar Bala
Masters Theses
"In the present work, surface roughness after machining of composite material was the main focus of study. Response surface methodology with Box- Behnken experimental design was applied in predicting the surface roughness (Ra) of abrasive waterjet cut 1-inch-thick graphite/epoxy composite. Second order response equations for Ra were generated with minitab, a statistical software as a function of pressure, traverse speed and isolated abrasive mesh size. Influence of each of these factors on the response were analyzed with 3D response surface plots. Abrasive mesh size was also found be a factor influencing Ra along with traverse speed and …
A Control Algorithm For The Solar Village Microgrid System, Hamad Ahmed Alharkan
A Control Algorithm For The Solar Village Microgrid System, Hamad Ahmed Alharkan
Masters Theses
"In this thesis, the concept of microgrid system is introduced. Also, the major components of a microgrid will be discussed thoroughly. Both grid-connected and autonomous modes are explained. In addition, the control of a microgrid is defined for the following types: local, centralized and decentralized control.
As one of the nation's premiere research universities, the Missouri University of Science and Technology has built four inspirational solar houses (solar villages) for a competition in the US Department of Energy Solar Decathlon to allow students to research and improve different aspects of the microgrid system. Consequently, this thesis develops a computer model …
Automated Design Of Boolean Satisfiability Solvers Employing Evolutionary Computation, Alex Raymond Bertels
Automated Design Of Boolean Satisfiability Solvers Employing Evolutionary Computation, Alex Raymond Bertels
Masters Theses
"Modern society gives rise to complex problems which sometimes lend themselves to being transformed into Boolean satisfiability (SAT) decision problems; this thesis presents an example from the program understanding domain. Current conflict-driven clause learning (CDCL) SAT solvers employ all-purpose heuristics for making decisions when finding truth assignments for arbitrary logical expressions called SAT instances. The instances derived from a particular problem class exhibit a unique underlying structure which impacts a solver's effectiveness. Thus, tailoring the solver heuristics to a particular problem class can significantly enhance the solver's performance; however, manual specialization is very labor intensive. Automated development may apply hyper-heuristics …
Mixing Dynamics In Municipal Water Storage Tanks, Pramod Narayan Bangalore
Mixing Dynamics In Municipal Water Storage Tanks, Pramod Narayan Bangalore
Masters Theses
"The purpose of this study is to investigate the effects of different control variables on mixing in municipal water storage tanks using Computational Fluid Dynamics(CFD) solutions with ANSYS FLUENT for isothermal, positively and negatively buoyant inflow conditions. Poor mixing of old water and new water leads to dead zone formation, which when introduced in the distribution system can cause major water quality issues. Data for this study was generated using Multiphase CFD flow modeling technique using Volume of Fluid (VOF) approach with species transport. The vessel was considered to be mixed when Coefficient of Variation (COV) dropped below 0.10.
Results …
3d Seismic Structural And Stratigraphic Interpretation Of The Tui-3d Field, Taranaki Basin, New Zealand, Gorkem Yagci
3d Seismic Structural And Stratigraphic Interpretation Of The Tui-3d Field, Taranaki Basin, New Zealand, Gorkem Yagci
Masters Theses
"Identifying seismic structures and stratigraphy are important for exploration of hydrocarbons. The purpose of this study is to discover seismic structural and stratigraphic features and to utilize the results for interpreting depositional environments. A 3D seismic dataset from the Tui-3D Field, the Taranaki Basin, New Zealand with well data were used to visualize structures, to detect stratigraphic features, to identify main lithology, to understand depositional environment, and to describe seismic facies and reflection patterns of the target horizons. The major formations are in the Kapuni Group.
Seismic structural interpretation indicates thirty-two minor faults, which may play an important role in …
Attenuation Properties Of Cement Composites: Experimental Measurements And Monte Carlo Calculations, Raul Florez
Attenuation Properties Of Cement Composites: Experimental Measurements And Monte Carlo Calculations, Raul Florez
Masters Theses
"Developing new cement based materials with excellent mechanical and attenuation properties is critically important for both medical and nuclear power industries. Concrete continues to be the primary choice material for the shielding of gamma and neutron radiation in facilities such as nuclear reactors, nuclear waste repositories, spent nuclear fuel pools, heavy particle radiotherapy rooms, particles accelerators, among others. The purpose of this research was to manufacture cement pastes modified with magnetite and samarium oxide and evaluate the feasibility of utilizing them for shielding of gamma and neutron radiation. Two different experiments were conducted to accomplish these goals. In the first …
Thrust Sensing For Small Uavs, Christopher Scott Marchman
Thrust Sensing For Small Uavs, Christopher Scott Marchman
Masters Theses
"Unmanned aerial vehicles (UAVs) have become prevalent in both military and civilian applications. UAVs have many size categories from large-scale aircraft to micro air vehicles. The performance, health, and efficiency for UAVs of smaller sizes can be difficult to assess and few associated instrumentation systems have been developed. Thrust measurements on the ground can characterize systems especially when combined with simultaneous motor power measurements. This thesis demonstrates the use of strain measurements to measure the thrust produced by motor/propeller combinations for such small UAVs. A full-bridge Wheatstone circuit and electrical resistance strain gauges were used in conjunction with constant-stress cantilever …
Structural Analysis And Fluid Flow Modeling Of The Kapuni Field, New Zealand, Jarret Taylor Baldwin
Structural Analysis And Fluid Flow Modeling Of The Kapuni Field, New Zealand, Jarret Taylor Baldwin
Masters Theses
"The Taranaki Basin is the largest hydrocarbon producing basin in New Zealand. A total area of over 330,000 km
Deterministic Simulation Of Thermal Neutron Radiography And Tomography, Rajarshi Pal Chowdhury
Deterministic Simulation Of Thermal Neutron Radiography And Tomography, Rajarshi Pal Chowdhury
Masters Theses
"In recent years, thermal neutron radiography and tomography have gained much attention as one of the nondestructive testing methods. However, the application of thermal neutron radiography and tomography hindered by their technical complexity, radiation shielding, and time-consuming data collection processes. Monte Carlo simulations have been developed in the past to improve the neutron imaging facility's ability. In this present work, a new deterministic simulation approach has been proposed and demonstrated to simulate neutron radiographs numerically using a ray tracing algorithm. This approach has made the simulation of neutron radiographs much faster than by previously used stochastic methods (i.e Monte Carlo …
Design Of A Microwave Imaging System For Rapid Wideband Imaging, Matthew Jared Horst
Design Of A Microwave Imaging System For Rapid Wideband Imaging, Matthew Jared Horst
Masters Theses
An imaging system composed of two linear arrays of antennas is designed through full-wave simulation and fabricated for use in synthetic aperture radar imaging. The arrays electronically scan along their antenna elements and are mechanically moved along a second orthogonal direction for scanning large two-dimensional areas quickly. Each linear array is printed on a circuit board where the antenna elements are integrated into the edge of the board as tapered slot-line antennas operating at 22 to 27 GHz. A multiplexer circuit is printed onto each linear array to transmit wideband signals to each antenna in the array. Receivers are printed …
Influence Of Mix Design Parameters On Dynamic Segregation Of Self-Consolidating Concrete And Consequences On Performance Of Precast Beams, Aida Margarita Ley Hernandez
Influence Of Mix Design Parameters On Dynamic Segregation Of Self-Consolidating Concrete And Consequences On Performance Of Precast Beams, Aida Margarita Ley Hernandez
Masters Theses
"Self-Consolidating Concrete (SCC) is more vulnerable to stability problems as a consequence of its high flowing ability compared to conventional vibrated concrete. Dynamic segregation refers to the tendency of the concrete constituents to separate from the suspended matrix, usually in horizontal direction while being cast into the formwork or due to an impact. Similarly to static segregation, dynamic segregation can affect the homogeneity of SCC. Therefore, it is highly essential to ensure a proper dynamic stability in order to enhance the uniformity of in-situ properties of pre-stressed beams.
In this research project, the effects of SCC mix design parameters are …
Developing An Idealistic Model To Characterize And Optimize A Photovoltaic Battery Systems, Pavani Reddy Nalladimmu
Developing An Idealistic Model To Characterize And Optimize A Photovoltaic Battery Systems, Pavani Reddy Nalladimmu
Masters Theses
"Solar energy is one of the most abundant and clean energy sources of renewable energy. Due to its unsteady nature, most photovoltaic systems require a solar storage system. Ultracapacitors have proven to be an effective solar energy storage component due to their wide range of input voltages and high power density. This research focuses on characterizing the performance of a PV/UCAP hybrid storage system to meet required household loads at various locations throughout the US as a backup energy source. A calibrated empirical model was developed to characterize system performance. A load profile was designed based on a typical 2 …
Intensity Control Of Dielectric Barrier Discharge Filaments, Matthew Crawford Paliwoda
Intensity Control Of Dielectric Barrier Discharge Filaments, Matthew Crawford Paliwoda
Masters Theses
"When operated in a filamentary mode, a volume dielectric barrier discharge (DBD) is known to produce patterned plasma structures. These structures are currently being explored for reconfigurable metamaterial applications. In this work the presence and intensity of a single filament, within an array of filaments, was controlled by adjusting the voltage to that filament's individual needle electrode. The current, voltage, and time-averaged normalized light intensity were measured while varying the voltage of the needle through a self-biasing resistance. For a 7.5 kV, 3.2 kHz DBD in air, the needle-controlled filament intensity varies from that of the surrounding filaments to zero …
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 …
Mixed Metal Oxide Catalysts Supported On H-Beta For Hydrogenolysis Of Glycerol Into 1,3-Propanediol, Amit Kant
Mixed Metal Oxide Catalysts Supported On H-Beta For Hydrogenolysis Of Glycerol Into 1,3-Propanediol, Amit Kant
Masters Theses
"Bioglycerol is the by-product which is produced largely from the microbial fermentation, hydrogenolysis of glucose in the mixture of polyols, fatty ester, soap manufacturing process and fatty acid production. Hydrogenolysis of glycerol is one of the most promising ways to convert glycerol and many work has been done towards 1,3-propanediol, 1,2-propanediol and 1-propanol using various metals and mixed-metal oxides such as W, Ru, Rh, Pt, Pd, Cu, Ni and different zeolites have been extensively used as the active components.
It has been well documented that the presence of Bronsted acid sites leads to the formation of acrolein, while Lewis acid …
Effect Of Timing And Source Of Online Product Recommendations: An Eye-Tracking Study, Qing Zeng
Effect Of Timing And Source Of Online Product Recommendations: An Eye-Tracking Study, Qing Zeng
Masters Theses
"Online retail business has become an emerging market for almost all business owners. Online recommender systems provide better services to the consumers as well as assist consumers with their decision making processes. In this study, a controlled lab experiment was conducted to assess the effect of recommendation timing (early, mid, and late) and recommendation source (expert reviews vs. consumer reviews) on e-commerce users' interest and attention. Eye-tracking data was extracted from the experiment and analyzed. The results suggest that users show more interest in recommendation based on consumer reviews than recommendation based on expert reviews. Earlier recommendations do not receive …
A Linear Matrix Inequality-Based Approach For The Computation Of Actuator Bandwidth Limits In Adaptive Control, Daniel Robert Wagner
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 …
Mitigation Of Wellbore Instability In Deviated Wells By Using Geomechanical Models And Mpd Technique, Husam Raad Abbood
Mitigation Of Wellbore Instability In Deviated Wells By Using Geomechanical Models And Mpd Technique, Husam Raad Abbood
Masters Theses
"During drilling operations for the E oilfield in the Mishrif formation in southern Iraq, stuck pipe presents a significant wellbore stability problem for deviated wells. In this study, two solutions are utilized to address this problem. The first approach is a 1-D Geomechanical model of the Mishrif formation compiled based on the state of stress and rock strength parameters. It is utilized to assess the contribution of borehole collapse leading to the stuck pipe problems. The results of this study show that wells characterized by stuck pipe are drilled along azimuths which promote wellbore collapse. Three different failure criteria, the …
Conceptual Parameters Necessary For Modeling Wettability Alteration In An Enhanced Smart Brine-Chalk System, Ahmed Abdulkareem Hussein Albahrani
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
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 …
Voltage Control In A Distribution System Using Active Power Loads, Mounika Chava
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 …
A Statistical Analysis Of A 4.5 Mw Solar Energy Center, Archit Patnaik
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 …
Addressing The Influence Of Carbon Monoxide On The Behavior Of An Hcci Engine, Allen Charles Ernst
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 …
An Investigation Of Plugging And Increasing Oil Recovery In Sandstone Porous Media By Micrometer-Size Particle Gel, Haifeng Ding
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 …
Design Methodology For Behavioral Surface Roughness Modeling And High-Speed Test Board Design, Xinyao Guo
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 …
Impact Of Repeated Cyclic Production Scheme On Eur In Low-Permeability Reservoirs, Samarth Gupte
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, …
Design, Scale-Up, Six Sigma In Processing Different Feedstocks In A Fixed Bed Downdraft Biomass Gasifier, Sai Chandra Teja Boravelli
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 …