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Articles 2191 - 2220 of 7906
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Chemical Quantification With Ubiquitous Optoelectronic Devices, Altamash Mukhtar Fakki
Chemical Quantification With Ubiquitous Optoelectronic Devices, Altamash Mukhtar Fakki
Masters Theses
"Optical sensing in medical diagnosis and chemical analysis using optoelectronic devices is a growing technology since it offers many advantages including real time analysis, remote sensing capability and low cost approach. This thesis demonstrates that an optical sensing platform utilizing optical mouse, the ubiquitous optoelectronic computer peripheral, can be used in quantitative oxygen and pH analysis.
Work in the first paper includes the use of optical mice for fluorescence intensity imaging of commercial oxygen patch. This involves gray color intensity analysis of filtered images to determine the gaseous oxygen level.
In the second paper, the optical mice is used to …
Evaluation Of Millimeter-Sized Preformed Particle Gel For Conformance Control Treatments Using Simple Models, Ali Abdulmohsen Al Brahim
Evaluation Of Millimeter-Sized Preformed Particle Gel For Conformance Control Treatments Using Simple Models, Ali Abdulmohsen Al Brahim
Masters Theses
Millimeter-sized preformed particle gels (PPGs) have been successfully used to tackle the high-permeable zones, fractures and channels in mature oilfields for conformance control improvement. PPGs can significantly reduce the permeability of abnormal fractures and divert injected water to the low permeable zones where hydrocarbon was not swept by previous water flooding. Due to the irregularity of PPGs in shapes after swollen, their strength cannot be easily measured using the conventional methods. Therefore, the open hole screen plate models with various hole diameters and density were designed to establish a simple technique that can be used to measure the strength of …
Determining Rockfall Volumes In Three Sites Along Habs Mountain Road In Southwestern Saudi Arabia, Using Lidar Technology, Abdullah Ayed Al-Otaibi
Determining Rockfall Volumes In Three Sites Along Habs Mountain Road In Southwestern Saudi Arabia, Using Lidar Technology, Abdullah Ayed Al-Otaibi
Masters Theses
"The rugged elevated topography is a characteristic feature of the western and southwestern regions of Saudi Arabia. Few arterial roads connect the scattered villages of these regions to major cities, such as Habs Road in Jazan region. Rock fall poses a serious hazard to people, property and animals along the rock cuts of this road. Although no traditional Rockfall studies have previously been applied to this road, accessibility and rock formation shape and structure variability influenced the choice of using Terrestrial Light Detection And Ranging (LiDAR) technology to calculate the volume of rockfall at selected sites along this road.
Software …
Experimental Study Of Crude Oil Emulsion Stability By Surfactants And Nanoparticles, Zainab Alabdulmohsen
Experimental Study Of Crude Oil Emulsion Stability By Surfactants And Nanoparticles, Zainab Alabdulmohsen
Masters Theses
"Surfactants and nanoparticles are materials being widely used for enhanced oil recovery (EOR). Surfactants are mainly used to reduce the interfacial tension between oil and water which could form a stable film of emulsion between these two immiscible fluids. Also, nanotechnology is a potential candidate to offer another solution to improve oil recovery. Nanoparticles can form a solid layer at the droplet's interface and stand as resistant stabilizer under harsh reservoir conditions.
This research investigates whether the combination of surfactants and nanoparticles can provide a more stable emulsion than surfactants only. Two parts of experimental study have been done in …
Sensor Authentication In Collaborating Sensor Networks, Jake Uriah Bielefeldt
Sensor Authentication In Collaborating Sensor Networks, Jake Uriah Bielefeldt
Masters Theses
"In this thesis, we address a new security problem in the realm of collaborating sensor networks. By collaborating sensor networks, we refer to the networks of sensor networks collaborating on a mission, with each sensor network is independently owned and operated by separate entities. Such networks are practical where a number of independent entities can deploy their own sensor networks in multi-national, commercial, and environmental scenarios, and some of these networks will integrate complementary functionalities for a mission. In the scenario, we address an authentication problem wherein the goal is for the Operator Oi of Sensor Network Si …
Experimental And Computational Analysis Of Thermosyphon Based Water Heaters, Siddarth Ashokkumar
Experimental And Computational Analysis Of Thermosyphon Based Water Heaters, Siddarth Ashokkumar
Masters Theses
"Storage type electric water heaters are one of the most commonly found type of heaters in households today. Due to energy costs and limited generation capacity, there is a need for improving the efficiency of such water heaters. The efficiency of water heating systems have impact both at the household and at the national level, because of their sheer numbers. Efficient water heaters lead to lower utility bills for the consumer and also reduced demand on the grid supplying electrical power to such households. This leads to a reduction in the amount of fuel used in generating electrical power and …
Numerical Study Of Upstream And Downstream Regions Of One Dimensional Detonation Wave In A Dusty Gas Medium, Shubhadeep Banik
Numerical Study Of Upstream And Downstream Regions Of One Dimensional Detonation Wave In A Dusty Gas Medium, Shubhadeep Banik
Masters Theses
"In detonative combustion very high temperatures are attained by the burned gases. As a result, a large amount of thermal energy is produced during the combustion process. This heat can affect the state of the unburned fuel through radiation of heat from the burned gases. In this study a one-dimensional model was deemed appropriate to gain insight into the fundamental structure of the detonation wave. In this model, the detonation wave divides the fluid stream into an upstream region, consisting of fuel and oxidant, and a downstream region, consisting of burned gases. A set of computer programs, some developed during …
Impact Of Configuration Variations On Small Modular Reactor Core Performance, William Kirby Compton
Impact Of Configuration Variations On Small Modular Reactor Core Performance, William Kirby Compton
Masters Theses
"One of the most promising new reactor designs is the Small Modular Reactor (SMR). These reactors, which operate under 300 MWe, will help bring cheap and safe nuclear energy to remote and centralized locations alike. Their ease of construction, advanced passive safety features, and cost effectiveness make these reactors an intriguing option for the near future.
In the work presented here, a neutronics analysis of the Westinghouse SMR was performed. Westinghouse's SMR design is a scaled down version of their AP1000 plant and will produce about 225 MWe of power. Though the parameters of the reactor core will be modeled …
Evaluation Of Preformed Particle Gel Treatment Using Homogeneous And Heterogeneous Models, Hilary Ogochukwu Elue
Evaluation Of Preformed Particle Gel Treatment Using Homogeneous And Heterogeneous Models, Hilary Ogochukwu Elue
Masters Theses
"This research investigates the effects of preformed particle gel (PPG) in remedying the problems of excess water production and low oil recovery of heterogeneous reservoirs by placing the PPG in the high-permeability layer, thus diverting displacing brine to the unswept low permeability layer. This investigation was completed with three tasks.
The first task was to evaluate the PPG swelling kinetics and strength as a function of concentration of brine. The result of this task indicate that PPG prepared with low concentration of brine swells more, becomes weaker, more deformable than PPG prepared with high concentration of brine.
The second task …
Computer Aided Detection Of Oral Lesions On Ct Images, Shaikat Mahmood Galib
Computer Aided Detection Of Oral Lesions On Ct Images, Shaikat Mahmood Galib
Masters Theses
"Oral lesions are important findings on computed tomography images. They are difficult to detect on CT images because of low contrast, arbitrary orientation of objects, complicated topology and lack of clear lines indicating lesions. In this thesis, a fully automatic method to detect oral lesions from dental CT images is proposed to identify (1) Closed boundary lesions and (2) Bone deformation lesions. Two algorithms were developed to recognize these two types of lesions, which cover most of the lesion types that can be found on CT images. The results were validated using a dataset of 52 patients. Using non training …
Comprehensive Benefits Of Green Roofs, Madison R. Gibler
Comprehensive Benefits Of Green Roofs, Madison R. Gibler
Masters Theses
"Green infrastructure uses vegetation, soils, and natural processes to manage water and create healthier urban environments, providing traditional roof services and alternative stormwater management technologies. Other benefits and impacts are not yet fully understood or valued. Research conducted assesses specific stormwater benefits of green roofs, providing information on nutrient leaching from media; and analyzes potential energy benefits through side-by-side comparisons of full-scale white, traditional black rubber, and green roofs in the mid-continent Missouri climate. Roofing media selection impacted leaching of nutrients, suspended solids, and organic carbon from the tested green roof media. Thermal properties were investigated at the building level, …
Mr4rf: Mem-Device With Impedance And Their Usage With Impedance Matching Networks For Passive Rfid Tags In The Uhf, George H. Harris
Mr4rf: Mem-Device With Impedance And Their Usage With Impedance Matching Networks For Passive Rfid Tags In The Uhf, George H. Harris
Masters Theses
"The passive RFID tag in the UHF has been employed in several different applications including, tracking, logistics, and as a sensing platform for the Internet of things (IoT). The tag is ideal for this industry due to its unique design. It harvests all of its energy from the environment, and is small, cheap, and requires little to no maintenance. However, there are two major issues limiting the potential of the passive RFID systems: the limited power harvested by the tag, and the high susceptibility to interference and coupling. In particular, dynamic environments render the traditionally fixed, RF impedance matching network …
Discrete-Time Neural Network Based State Observer With Neural Network Based Control Formulation For A Class Of Systems With Unmatched Uncertainties, Jason Michael Stumfoll
Discrete-Time Neural Network Based State Observer With Neural Network Based Control Formulation For A Class Of Systems With Unmatched Uncertainties, Jason Michael Stumfoll
Masters Theses
"An observer is a dynamic system that estimates the state variables of another system using noisy measurements, either to estimate unmeasurable states, or to improve the accuracy of the state measurements. The Modified State Observer (MSO) is a technique that uses a standard observer structure modified to include a neural network to estimate system states as well as system uncertainty. It has been used in orbit uncertainty estimation and atmospheric reentry uncertainty estimation problems to correctly estimate unmodeled system dynamics. A form of the MSO has been used to control a nonlinear electrohydraulic system with parameter uncertainty using a simplified …
Parameter Determination And Experimental Validation Of A Wire Feed Additive Manufacturing Model, Kannan Suresh Kumar
Parameter Determination And Experimental Validation Of A Wire Feed Additive Manufacturing Model, Kannan Suresh Kumar
Masters Theses
“Laser metal deposition is an additive manufacturing method with great scope and robustness. The wire fed additive manufacturing method has great opportunities in space applications and other zero gravity manufacturing processes. Process parameters play an important role in controlling the complex phenomenon and obtaining an ideal manufactured part. These parameters can be efficiently determined using simulation tools which are highly essential in visualizing real world experiments, therefore saving time and experimental costs. The objective of this study is to develop a transient 3D model of laser aided wire feed metal deposition which realizes the heat transfer and fluid flow behavior …
A Force Feedback Haptic Interface For Atomic Force Microscopy, Abdulmohsen Alabdulmuhsin
A Force Feedback Haptic Interface For Atomic Force Microscopy, Abdulmohsen Alabdulmuhsin
Masters Theses
"Integrating a force feedback haptic device with atomic force microscopy (AFM) improves the capability to investigate and manipulate the objects on a micro- and nanoscale surface. The haptic device provides the researcher with a sense of touch and movement by changing the position of the stylus or amount of force on it. The developed system's concept is to provide the user a sense and feel and control of the AFM probe at the nanoscale. By positing the haptic stylus, the user generates reference to commands to the AFM probe. In turn, forces experienced by the probe are communicated to the …
Hybrid Manufacturing Process Of SicF/Sic Composite Using Preceramic Polymer, Robert Raymond Meinders
Hybrid Manufacturing Process Of SicF/Sic Composite Using Preceramic Polymer, Robert Raymond Meinders
Masters Theses
"Continuous fiber-reinforced silicon carbide (SiCf/SiC) ceramic composites have been increasingly used due to their high temperature strength and graceful failure mechanisms. A disadvantage is the high cost and lengthy production processes that are required to develop these materials. Polymer infiltration and pyrolysis (PIP) is one of the most attractive fabrication processes for composites due to shape flexibility, mass production and relatively low cost; however, the quality of material obtained by this method has been considered insufficient due to the microstructure defects of the material obtained. This study investigated a hybrid of multiple polymer manufacturing processes to maximize quality …
On The Dynamic Analysis Of Compliant Mechanisms Based On The Pseudo-Rigid-Body Model, Andrew Christian
On The Dynamic Analysis Of Compliant Mechanisms Based On The Pseudo-Rigid-Body Model, Andrew Christian
Masters Theses
"Compliant mechanisms derive some or all of their mobility from the deflection of flexible members. A pseudo-rigid-body model (PRBM) provides an elegant and simple way of modeling and analyzing traditionally nonlinear large-deflection problems pertaining to compliant mechanisms. In this work, several aspects pertainting to the dynamics of compliant mechanisms are considered. First, dynamic models are derived to predict not only the natural frequency of the large-deflection systems, but also the transient response, using the PRBM approach. A unique multi-stage damping model is developed to determine the transient response in free vibration. Recent works have neglected to consider the transient response …
On The Design Of A Nearly Constant-Force Modular Device Based On A Compliant Slider Mechanism, Krutika Karthik
On The Design Of A Nearly Constant-Force Modular Device Based On A Compliant Slider Mechanism, Krutika Karthik
Masters Theses
"Compliant mechanisms derive some or all of their mobility from the deflection of their flexible members. A pseudo-rigid-body model (PRBM) provides a simple and efficient way of modeling and analyzing large deflections in compliant mechanisms. In this work, a partially compliant slider mechanism, composed of rigid and compliant segments as well as rigid-body revolute and prismatic pairs, is considered. In recent works, such mechanisms have been dimensionally synthesized to produce substantially constant-force output over a finite range of input link displacement in an in-line PRBM of a compliant slider mechanism. In this thesis, the current practice of using partially compliant …
American Sign Language Alphabet Recognition Using Microsoft Kinect, Cao Dong
American Sign Language Alphabet Recognition Using Microsoft Kinect, Cao Dong
Masters Theses
"American Sign Language (ASL) fingerspelling recognition using marker-less vision sensors is a challenging task due to the complexity of ASL signs, self-occlusion of the hand, and limited resolution of the sensors. This thesis describes a new method for ASL fingerspelling recognition using a low-cost vision camera, which is Microsoft's Kinect. A segmented hand configuration is first obtained by using a depth contrast feature based per-pixel classification algorithm. Then, a hierarchical mode-finding method is developed and implemented to localize hand joint positions under kinematic constraints. Finally, a Random Decision Forest (RDF) classifier is built to recognize ASL signs according to the …
Effect Of Polymer On Disproportionate Permeability Reduction To Gas And Water For Fractured Shales, Lingbo Liu
Effect Of Polymer On Disproportionate Permeability Reduction To Gas And Water For Fractured Shales, Lingbo Liu
Masters Theses
"Large volumes of fracturing fluid are required in shale slickwater fracs, and a considerable amount of polymer friction reducer would remain in microfractures if the polymer has not been broken before gas production. It is of major interest to evaluate the effect of polymer on water/gas flow behavior in the microfractures of shale reservoirs. We fabricated six shale fracture models with different fracture widths and set up a core flooding apparatus to conduct brine/gas-injection experiments before and after polymer treatment. A method by which to calculate the residual resistance factor for gas (Frr,gas) was defined. The experimental results …
An Experimental Study Of Fabrication Temperature Effect On Aqueous Extrusion Freeform Fabrication, Jie Li
An Experimental Study Of Fabrication Temperature Effect On Aqueous Extrusion Freeform Fabrication, Jie Li
Masters Theses
"In order to understand the effect of fabrication temperature, a computer controlled 3-D gantry system was used to extrude aqueous alumina paste using Extrusion Freeform Fabrication. The system includes a temperature control subsystem that allows for fabrication of components below the paste's freezing temperature in the range of -10⁰C to -30⁰C and a hot plate with temperature in the range of 20⁰C to 80⁰C inside a room temperature chamber. Comparisons in terms of relative density, mechanical properties, part accuracy and minimum deposition angle were performed by Extrusion Freeform Fabrication at 40⁰C plate temperature inside a room temperature chamber and at …
Emission And Energy Analysis Of Self-Sufficient Biomass Power Plant To Achieve Near Net Zero Co₂ Emission, Baburaj Kanagarajan
Emission And Energy Analysis Of Self-Sufficient Biomass Power Plant To Achieve Near Net Zero Co₂ Emission, Baburaj Kanagarajan
Masters Theses
"The use of biomass to fuel power plants is considered by many to be a carbon neutral solution to carbon dioxide emissions. One objection to this method of power generation is the gasoline or diesel spent in the transportation and feedstock production, which is a major contributor to carbon emission. In addition, costs associated with the transportation of the biomass fuels are also a major limiting. This work investigates the use of a hybrid farming facility as a means of distributed generation combined. A model that incorporates a small scale biomass power facility located within a farming facility is examined. …
Esd Event Locator, Syed Abrar Ul Huq
Esd Event Locator, Syed Abrar Ul Huq
Masters Theses
"Electrostatic Discharge (ESD) presents one of the most common threats to electronic systems especially in the cases of high-speed digital systems. ESD event locator systems have been designed to determine the location of the source of the ESD event using different techniques. One such method of determining the origin of the ESD event, is the use of four antennas and a high-speed Analog to Digital Converter (ADC) system to capture the ESD events.
This thesis presents such an implementation which deals with the design of an analog front-end to a fast TI LM97600 ADC and a Virtex-5 Field-Programmable Gated Array …
Design And Implementation Of A 20 Ghz Ultra-Wide Bandwidth Channel Emulator For Differential High Speed Serial Data Links, Wei Qian
Masters Theses
"High speed serial link is now the dominant signal propagation design in various communication, computing and embedded applications. Emulation of such channels is important in signal integrity design and product testing, where full channel simulation is restricted due to the need for protection of intellectual property and frequent channel reconfiguration. This thesis introduces robust lossy material and FIR filter design methods that can be used for channel emulation to provide a solution under these restrictions. Based on the channel characterizations normally obtained in the frequency domain by vector network analysis, different emulation strategies and optimization techniques are utilized to emulate …
A Study Into Improving Transformer Loading Capability Beyond Nameplate Rating, Aakanksha Pasricha
A Study Into Improving Transformer Loading Capability Beyond Nameplate Rating, Aakanksha Pasricha
Masters Theses
"Utilities are becoming increasingly interested in the prospect of overloading the transformers beyond the nameplate rating to meet the increased demand for power as it may be more economically viable than installing a new transformer. The safety of the transformer has to be ensured while overloading it and hence there is a maximum loading beyond which the transformer should not be overloaded. A study has been performed on 38 transformer units and the factors that limit their overloading capability have been analyzed. Ancillary equipment ratings were found to be the most prominent limiting factor. Several case studies and evaluation results …
Model Predictive Current Control Of Switched Reluctance Motor With Inductance Auto-Calibration, Xin Li
Model Predictive Current Control Of Switched Reluctance Motor With Inductance Auto-Calibration, Xin Li
Masters Theses
"The thesis is composed of three papers, which investigate the application of Model Predictive Controller (MPC) for current control of Switched Reluctance Motor (SRM). Since the conventional hysteresis current control method is not suitable for high power SRM drive system with low inductance and limited switching frequency, MPC is a promising alternative approach for this application. The proposed MPC can cope with the measurement noise as well as uncertainties within the machine inductance profile. In the first paper, a MPC current control method for Double-Stator Switched Reluctance Motor (DSSRM) drives is presented. A direct adaptive estimator is incorporated to follow …
A New Technique For Modeling The Geomorphology Of A Slow Moving, Soft-Slope Landslide Using Terrestrial Lidar, Nathan Bradley Rohrbaugh
A New Technique For Modeling The Geomorphology Of A Slow Moving, Soft-Slope Landslide Using Terrestrial Lidar, Nathan Bradley Rohrbaugh
Masters Theses
"Soft slope movement is a big problem whether it involves an engineered slope, one that is near infrastructure, or both. Active landslides that fail slowly sometimes allow ample time to affect remedial works. In order to plan effective remedial works, there needs to be a model of the entire geometry of the slide. This thesis describes a new approach to evaluate the morphology of slope geometry using Light Detection and Ranging (LiDAR) data obtained from simple targets strategically positioned on a slide body. The data was gathered in three-month intervals over a period of one year to allow enough time …
Experimental And Computational Evaluation Of Water Management And Performance Of A Bio-Inspired Pem Fuel Cell In Comparison To A Conventional Flow Field, Venkatanaga Bhaskar Prakash Saripella
Experimental And Computational Evaluation Of Water Management And Performance Of A Bio-Inspired Pem Fuel Cell In Comparison To A Conventional Flow Field, Venkatanaga Bhaskar Prakash Saripella
Masters Theses
"Fuel cells are being increasingly used in various stationary and transportation power applications due to their higher energy efficiency and lower pollution. Flow field design in Proton Exchange Membrane (PEM) fuel cells is a major area of research for performance improvement. Bio-inspired flow field designs have significant potential for increased performance by effective distribution of reactants with better water management capabilities. In this study, a bio-inspired flow field design, formulated using Murray's law and mimicking a typical leaf venation pattern, is experimentally and computationally investigated in comparison to a conventional single serpentine design. Experiments are conducted using a special transparent …
Fuzzy Adaptive Resonance Theory: Applications And Extensions, Clayton Parker Smith
Fuzzy Adaptive Resonance Theory: Applications And Extensions, Clayton Parker Smith
Masters Theses
"Adaptive Resonance Theory, ART, is a powerful clustering tool for learning arbitrary patterns in a self-organizing manner. In this research, two papers are presented that examine the extensibility and applications of ART. The first paper examines a means to boost ART performance by assigning each cluster a vigilance value, instead of a single value for the whole ART module. A Particle Swarm Optimization technique is used to search for desirable vigilance values. In the second paper, it is shown how ART, and clustering in general, can be a useful tool in preprocessing time series data. Clustering quantization attempts to meaningfully …
Signal Integrity Analysis Of A Low Cost Pcb To Pcb System, Kancy Robison
Signal Integrity Analysis Of A Low Cost Pcb To Pcb System, Kancy Robison
Masters Theses
"This report presents the analysis of a low cost PCB to PCB cable and connector system focusing on its data rate limitations and optimizing transmitter and receiver operations. Economic factors have an ineluctable presence in digital hardware engineering and, as data rates are continually pushed to new bounds, finding cheaper alternatives in hardware while maintaining performance standards becomes more relevant. This study will show the measurement and simulation of a low cost digital system which includes a PCB board, connector, and a multi-pin flex cable (ribbon cable). These S-parameter and TDR measurements/simulations are used to gain an intuition for the …