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Full-Text Articles in Engineering

Strain Monitoring Of Carbon Fiber Composite With Embedded Nickel Nano-Composite Strain Gage, Timothy Michael Johnson Apr 2011

Strain Monitoring Of Carbon Fiber Composite With Embedded Nickel Nano-Composite Strain Gage, Timothy Michael Johnson

Theses and Dissertations

Carbon fiber reinforced plastic (CFRP) composites have extensive value in the aerospace, defense, sporting goods, and high performance automobile industries. These composites have huge benefits including high strength to weight ratios and the ability to tailor their properties. A significant issue with carbon fiber composites is the potential for catastrophic fatigue failure. To better understand this fatigue, there is first a huge push to measure strain accurately and in-situ to monitor carbon fiber composites. In this paper, piezoresistive nickel nanostrand (NiNs) nanocomposites were embedded in between layers of carbon fiber composite for real time, in situ strain monitoring. Several different …

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The Composition And Distribution Of Coal-Ash Deposits Under Reducing And Oxidizing Conditions From A Suite Of Eight Coals, David R. Brunner Apr 2011

The Composition And Distribution Of Coal-Ash Deposits Under Reducing And Oxidizing Conditions From A Suite Of Eight Coals, David R. Brunner

Theses and Dissertations

Eighteen elements, including: carbon, oxygen, sodium, magnesium, aluminum, silicon, phosphorus, sulfur, chlorine, potassium, calcium, titanium, chromium, manganese, iron, nickel, strontium, and barium were measured using a scanning electron microscope with energy dispersive spectroscopy from deposits. The deposits were collected by burning eight different coals in a 160 kWth, staged, down-fired, swirl-stabilized combustor. Both up-stream and down-stream deposits from an oxidizing region (equivalence ratio 0.86) and reducing region (equivalence ratio 1.15) were collected. Within the deposits, the particle size and morphology were studied. The average particle cross-sectional area from the up-stream deposits ranged from 10 - 75 µm2 and had a …

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Multi-Resolution Obstacle Mapping With Rapidly-Exploring Random Tree Path Planning For Unmanned Air Vehicles, Brett Wayne Millar Apr 2011

Multi-Resolution Obstacle Mapping With Rapidly-Exploring Random Tree Path Planning For Unmanned Air Vehicles, Brett Wayne Millar

Theses and Dissertations

Unmanned air vehicles (UAVs) have become an important area of research. UAVs are used in many environments which may have previously unknown obstacles or sources of danger. This research addresses the problem of obstacle mapping and path planning while the UAV is in flight. Online obstacle mapping is achieved through the use of a multi-resolution map. As sensor information is received, a quadtree is built up to hold the information based upon the uncertainty associated with the measurement. Once a quadtree map of obstacles is built up, we desire online path re-planning to occur as quickly as possible. We introduce …

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Accelerating Finite State Projection Through General Purpose Graphics Processing, Thomas Trimeloni Apr 2011

Accelerating Finite State Projection Through General Purpose Graphics Processing, Thomas Trimeloni

Theses and Dissertations

The finite state projection algorithm provides modelers a new way of directly solving the chemical master equation. The algorithm utilizes the matrix exponential function, and so the algorithm’s performance suffers when it is applied to large problems. Other work has been done to reduce the size of the exponentiation through mathematical simplifications, but efficiently exponentiating a large matrix has not been explored. This work explores implementing the finite state projection algorithm on several different high-performance computing platforms as a means of efficiently calculating the matrix exponential function for large systems. This work finds that general purpose graphics processing can accelerate …

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Experimental Investigation Of Natural Fiber Reinforced Composite, Irene Samy Fahim Apr 2011

Experimental Investigation Of Natural Fiber Reinforced Composite, Irene Samy Fahim

Theses and Dissertations

There is a growing use of polymers in different applications worldwide. This phenomenon resulted in an enormous increase in the amount of plastic waste. These wastes have significant impacts on the environment including pollution and depletion of resources. Recycling plastic waste and reusing it helps in alleviating environmental degradation. The amount of recycled plastics all over the world not utilized is huge. U.S.A recycled 5.7% of the total plastics generated and Western Europe recycled 39% of total amount of plastics consumed [1]. This research studies the potential usage of virgin and recycled polymer reinforced with natural fiber such as rice …

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Fm Demodulators In Software-Defined Radio Using Fpgas With Rapid Prototyping, Marc Anthony Padilla Mar 2011

Fm Demodulators In Software-Defined Radio Using Fpgas With Rapid Prototyping, Marc Anthony Padilla

Theses and Dissertations

With the advent of software-defined radio, many radio applications have and are currently being designed for FPGAs, due to their high performance and reconfigurability. Invariably, "legacy" waveforms, such as FM, will need to be supported in such systems. A challenge that comes with programming FPGAs is the increased design and implementation time over conventional software programming. In this thesis, three FM demodulator techniques are implemented and compared in an FPGA. Two techniques are found to have similar SNR performance while having very different FPGA implementation characteristics. Library based design is explored for demodulators to increase FPGA design productivity. A block …

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Characterization And Genetic Analysis Of The Cellulolytic Microorganism Thermobifida Fusca, Yu Deng Mar 2011

Characterization And Genetic Analysis Of The Cellulolytic Microorganism Thermobifida Fusca, Yu Deng

Theses and Dissertations

Currently, one of the hurdles hindering efficient production of cellulosic biofuel is the recalcitrant nature of cellulose to hydrolysis. A wide variety of cellulase enzymes are found natively in microorganisms that can potentially be used to effectively hydrolyze cellulose to fermentable sugars. Thermobifida fusca is a high G-C content, thermophilic, gram-positive soil actinobacterium with high cellulolytic activity. The phenomenological and mechanistic parameters affecting cellulase activity were studied in T. fusca and two mechanisms have been found: 1) transcriptions of cellulase-related genes were not closely associated with measured differences in cellulase activity and 2) cellular energetics (intracellular ATP) correlated more closely …

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Quest Hierarchy For Hyperspectral Face Recognition, David M. Ryer Mar 2011

Quest Hierarchy For Hyperspectral Face Recognition, David M. Ryer

Theses and Dissertations

Face recognition is an attractive biometric due to the ease in which photographs of the human face can be acquired and processed. The non-intrusive ability of many surveillance systems permits face recognition applications to be used in a myriad of environments. Despite decades of impressive research in this area, face recognition still struggles with variations in illumination, pose and expression not to mention the larger challenge of willful circumvention. The integration of supporting contextual information in a fusion hierarchy known as QUalia Exploitation of Sensor Technology (QUEST) is a novel approach for hyperspectral face recognition that results in performance advantages …

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Evaluation Of Portable Devices For Monitoring Microcracking Of Cement-Treated Base Layers, Charles A. Hope Mar 2011

Evaluation Of Portable Devices For Monitoring Microcracking Of Cement-Treated Base Layers, Charles A. Hope

Theses and Dissertations

A relatively new method used to reduce the amount of cement-treated base (CTB) shrinkage cracking is microcracking of the CTB shortly after construction. Three portable instruments used in this study for monitoring the microcracking process include the heavy Clegg impact soil tester (CIST), portable falling-weight deflectometer (PFWD), and soil stiffness gauge (SSG). The specific objectives of this research were 1) to evaluate the sensitivity of each of the three portable instruments to microcracking, and 2) to compare measurements of CTB stiffness reduction obtained using the three devices. The test locations included in this study were Redwood Drive and Dale Avenue …

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Fiber Optic Sensor Interrogation Advancements For Research And Industrial Use, Wesley Mont Kunzler Mar 2011

Fiber Optic Sensor Interrogation Advancements For Research And Industrial Use, Wesley Mont Kunzler

Theses and Dissertations

Spectrally-based fiber optic sensors are a rapidly maturing technology capable of sensing several environmental parameters in environments that are unfitting to electrical sensors. However, the sensor interrogation systems for this type of sensors are not yet fit to replace conventional sensor systems. They lack the speed, compact size, and usability necessary to move into mainstream test and measurement. The Fiber Sensor Integrated Monitor (FSIM) technology leverages rapid optical components and parallel hardware architecture to move these sensors across the research threshold into greater mainstream use. By dramatically increasing speed, shrinking size, and targeting an interface that can be used in …

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Development Of Single-Chip Silicon Photonic Microcantilever Arrays For Sensing Applications, Weisheng Hu Mar 2011

Development Of Single-Chip Silicon Photonic Microcantilever Arrays For Sensing Applications, Weisheng Hu

Theses and Dissertations

Microcantilever arrays have been shown to be promising label-free nanomechanical sensing devices with high sensitivity. Two factors that affect the usefulness of microcantilevers in sensing scenarios are the sensitivity of the transduction method for measuring changes in microcantilever properties and the ability to create large compact arrays of microcantilevers. In this dissertation, we demonstrate that microcantilevers with an in-plane photonic transduction method are attractive because they maintain the sensitivity of the traditional laser beam reflection method while being scalable to simultaneous readout of large microcantilever arrays. First I demonstrate the integration of a compact waveguide splitter network with in-plane photonic …

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Calibration Of The Highway Safety Manual Safety Performance Function And Development Of Jurisdiction-Specific Models For Rural Two-Lane Two-Way Roads In Utah, Bradford Keith Brimley Mar 2011

Calibration Of The Highway Safety Manual Safety Performance Function And Development Of Jurisdiction-Specific Models For Rural Two-Lane Two-Way Roads In Utah, Bradford Keith Brimley

Theses and Dissertations

This thesis documents the results of the calibration of the Highway Safety Manual (HSM) safety performance function (SPF) for rural two-lane two-way roadway segments in Utah and the development of new SPFs using negative binomial and hierarchical Bayesian modeling techniques. SPFs estimate the safety of a roadway entity, such as a segment or intersection, in terms of number of crashes. The new SPFs were developed for comparison to the calibrated HSM SPF. This research was performed for the Utah Department of Transportation (UDOT).The study area was the state of Utah. Crash data from 2005-2007 on 157 selected study segments provided …

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Strength And Deformation Characteristics Of A Cement-Treated Reclaimed Pavement With A Chip Seal, Bryan T. Wilson Mar 2011

Strength And Deformation Characteristics Of A Cement-Treated Reclaimed Pavement With A Chip Seal, Bryan T. Wilson

Theses and Dissertations

The objective of this research was to analyze the strength and deformation characteristics of a cement-treated base (CTB) constructed using full-depth reclamation, microcracked, and then surfaced with a single chip seal. In this field study, strength characteristics of the CTB layer were determined at the time of construction, and then both strength and deformation characteristics were evaluated after 9 months of low-volume, heavy truck traffic. After 9 months, observed distresses included transverse cracking, rutting, and chip seal joint failure. The loss of the chip seal was caused by poor chip seal construction practices and not a deficiency in the CTB …

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Increasing Design Productivity For Fpgas Through Ip Reuse And Meta-Data Encapsulation, Adam T. Arnesen Mar 2011

Increasing Design Productivity For Fpgas Through Ip Reuse And Meta-Data Encapsulation, Adam T. Arnesen

Theses and Dissertations

As Moore's law continues to progress, it is becoming increasingly difficult for hardware designers to fully utilize the increasing number of transistors available semiconductor devices including FPGAs. This design productivity gap must be addressed to allow designs to take full advantage of the increased logic density that results from rising transistor density. The reuse of previously developed and verified intellectual property (IP) is one approach that has claimed to narrow the design productivity gap. Reuse, however, has proved difficult to realize in practice because of the complexity of IP and the reluctance of designers to reuse IP that they do …

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Automatic All-Hex Topology Operations Using Edge Valence Prediction With Application To Localized Coarsening, Timothy Ira Miller Mar 2011

Automatic All-Hex Topology Operations Using Edge Valence Prediction With Application To Localized Coarsening, Timothy Ira Miller

Theses and Dissertations

In this work, we propose using edge valence as a quality predictor when used as a driver for adapting all hexahedral meshes. Edge valence, for hexahedra, is defined as the number of faces attached to an edge. It has shown to be a more reliable quality predictor than node valence for hexahedral meshes. An edge valence of 3, 4, or 5 within the volume of a hexahedral mesh has provided at least a positive scaled Jacobian for all observed meshes, without the presence of over constraining geometry. It is often desirable to adapt an existing mesh through sheet operations such …

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Analysis Of Selected Factors Affecting Concrete Cover Measurements On Bridge Decks, Jeffrey Ryan Hoki Mar 2011

Analysis Of Selected Factors Affecting Concrete Cover Measurements On Bridge Decks, Jeffrey Ryan Hoki

Theses and Dissertations

The objective of this research was to quantify the effects of selected parameters on the accuracy of concrete cover measurements on bridge decks. This research involved three full-factorial laboratory experiments each designed to investigate one of three primary variables. These primary variables included distance to a parallel adjacent bar, distance to a reinforcement intersection, and incorrect bar size input for the cover meter. Each experiment also involved four secondary variables known to affect cover readings. These secondary variables included actual cover depth, meter brand, antenna type, and bar size. Statistical analyses were performed to determine the significance of each factor. …

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Temporal And Spatial Variability In Base Materials Treated With Asphalt Emulsion, Tyler James Quick Mar 2011

Temporal And Spatial Variability In Base Materials Treated With Asphalt Emulsion, Tyler James Quick

Theses and Dissertations

The first objective of this research was to investigate temporal trends in the mechanical properties of base materials stabilized with asphalt emulsion and to assess the rate at which emulsion-treated base (ETB) design properties are achieved. The second objective of this research was to identify construction and environmental factors most correlated to specific mechanical properties of ETB layers and to determine which construction factors exhibit the greatest variability. Additional statistical analysis was performed to determine if significant differences existed between different test sections on a given project. In this research, three experimental sections were established along a pavement reconstruction project …

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A Gis-Based Data Model And Tools For Analysis And Visualization Of Levee Breaching Using The Gssha Model, Hoang Luu Tran Mar 2011

A Gis-Based Data Model And Tools For Analysis And Visualization Of Levee Breaching Using The Gssha Model, Hoang Luu Tran

Theses and Dissertations

Levee breaching is the most frequent and dangerous form of levee failure. A levee breach occurs when floodwater breaks through part of the levee creating an opening for water to flood the protected area. According to National Committee on Levee Safety (NCLS), a reasonable upper limit for damage resulting from levee breaching is around $10 billion per year during 1998 and 2007. This number excludes hurricanes Katrina and Rita in 2005 which resulted in economic damages estimated to be more than $200 billion dollar and a loss of more than 1800 lives. In response to these catastrophic failures, the U.S. …

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A Study Of The Cause Of Failure Of Rotationally Molded, High-Density Polyethylene, Sodium Hypochlorite Storage Tanks, Dixon Harold Abell Mar 2011

A Study Of The Cause Of Failure Of Rotationally Molded, High-Density Polyethylene, Sodium Hypochlorite Storage Tanks, Dixon Harold Abell

Theses and Dissertations

The topic of chemical oxidative degradation in rotational molded polyethylene (high-density cross-linked) chemical (sodium hypochlorite) storage tanks is an industry problem that ranks at the top of current business issues for manufacturers of chemical storage tanks. The degradation of these tanks not only compromises the physical and mechanical properties of the tank material, but reduces the life expectancy of the tank, eventually resulting in catastrophic tank failure. Premature tank failure comes at a hefty cost. The reputation of the manufacturer is questioned often resulting in immediate loss of customer satisfaction and future business. The leaking of the chemical from the …

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Pyrolysis Kinetics And Chemical Structure Considerations Of A Green River Oil Shale And Its Derivatives, James L. Hillier Mar 2011

Pyrolysis Kinetics And Chemical Structure Considerations Of A Green River Oil Shale And Its Derivatives, James L. Hillier

Theses and Dissertations

This work had the objective of determining both the kinetic parameters for the pyrolysis of oil shale and kerogen as well as using analytical techniques coupled with pyrolysis to shed light on the structure of a specific Green River oil shale. Because of the problems with linearized methods and disagreement among literature values and methods, a new method was developed tofit kinetic parameters to non linearized data. The method was demonstrated to determine the "correct" answer for mathematically generated data within a few percent error and was shown to have a lower sum squared error than the linearized methods. The …

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A Proteolytic Process To Simulate The Mechanics Of Disc Dengeration In Bovine Cadaveric Tissue, Timothy A. Bishop Mar 2011

A Proteolytic Process To Simulate The Mechanics Of Disc Dengeration In Bovine Cadaveric Tissue, Timothy A. Bishop

Theses and Dissertations

Purpose. The present work hypothesized that proteolytic dissolution of intervertebral discs could induce biomechanical change comparable to the change observed in natural disc degeneration. A method to do such could be utilized for in vitro research where intersample differences in geometry and chemical makeup render it difficult to compare and aggregate results into generalized conclusions.
Methods. Forty-one bovine coccygeal intervertebral discs were isolated with individual functional spinal units. Samples were loaded in three modes: compression/tension, flexion/extension, and axial rotation. The anulus fibrosus of each disc was injected with 200µl trypsin or fetal bovine serum (control) and incubated for an allotted …

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Developing Methods To Assess The Potential Effects Of Global Climate Change On Deer Creek Reservoir Using Water Quality Modeling, Reed Earl Chilton Mar 2011

Developing Methods To Assess The Potential Effects Of Global Climate Change On Deer Creek Reservoir Using Water Quality Modeling, Reed Earl Chilton

Theses and Dissertations

To evaluate the potential impacts of future climate change on a temperate reservoir, I used a calibrated water quality and hydrodynamic model validated using three years of data (2007-2009) from Deer Creek Reservoir (Utah). I evaluated the changes due to altered air temperatures, inflow rates, and nutrient loads that might occur under Global Climate Change (GCC). I developed methods to study GCC on reservoirs. I produced Average Water Temperature Plots, Stratification Plots, and Total Concentration Plots. Average Water Temperature Plots show the sensitivity of the water temperature to various parameters. Stratification Plots quantify stratification length and strength as well as …

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Automated Delay Estimation At Signalized Intersections: Phase I Concept And Algorithm Development, Taylor R. Forbush Mar 2011

Automated Delay Estimation At Signalized Intersections: Phase I Concept And Algorithm Development, Taylor R. Forbush

Theses and Dissertations

Currently there are several methods to measure the performance of surface streets, but their capabilities in dynamically estimating vehicle delay are limited. The objective of this research is to develop a method to automate traffic delay estimation in real-time using existing field traffic data collection technologies. This research has focused on method and algorithm development that can be applied to existing technologies. Two algorithms were developed to run automatically using Microsoft Excel and Visual Basic to calculate traffic delay from data collected from existing vehicle detection. The algorithms were developed using computer modeling software to simulate different lane configurations. The …

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Culvert Roughness Elements For Native Utah Fish Passage: Phase I, Lindsay D. Esplin Mar 2011

Culvert Roughness Elements For Native Utah Fish Passage: Phase I, Lindsay D. Esplin

Theses and Dissertations

Culverts can increase stream velocities as a result of reduced waterway areas and prevent upstream passage of small non-salmonid fish such as the Native Utah Leatherside chub (Gila copei) and Longnose dace (Rhinichthyscataractae). To mitigate this problem, current culvert design standards for fish passage match sustained fish swim speeds with average cross sectional velocity through the culvert. Such policies dictate relatively large barrels and do not recognize the role of reduced velocity zones near culvert boundaries. Obstacles and streambed substrate create turbulent regions with lower velocity zones that can increase upstream fish passage. A comparison of …

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A High-Gain, Low-Power Cmos Operational Amplifier Using Composite Cascode Stage In The Subthreshold Region, Rishi Pratap Singh Mar 2011

A High-Gain, Low-Power Cmos Operational Amplifier Using Composite Cascode Stage In The Subthreshold Region, Rishi Pratap Singh

Theses and Dissertations

This thesis demonstrates that the composite cascode differential stage, operating in the subthreshold region, can form the basis of a high gain (113 dB) and low-power op amp (28.1 µW). The circuit can be fabricated without adding a compensation capacitance. The advantages of this architecture include high voltage gain, low bandwidth, low harmonic distortion, low quiescent current and power, and small chip area. These advantages suggest that this design might be well-suited for biomedical applications where low power, low noise bio-signal amplifiers capable of amplifying signals in the millihertz-to-kilohertz range is required.

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System Identification, State Estimation, And Control Of Unmanned Aerial Robots, Caleb H. Chamberlain Mar 2011

System Identification, State Estimation, And Control Of Unmanned Aerial Robots, Caleb H. Chamberlain

Theses and Dissertations

This thesis describes work in a variety of topics related to aerial robotics, including system identification, state estimation, control, and path planning. The path planners described in this thesis are used to guide a fixed-wing UAV along paths that optimize the aircraft's ability to track a ground target. Existing path planners in the literature either ignore occlusions entirely, or they have limited capability to handle different types of paths. The planners described in this thesis are novel in that they specifically account for the effect of occlusions in urban environments, and they can produce a much richer set of paths …

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Characterization And In Vitro Toxicity Of Copper Nanoparticles (Cu-Nps) In Murine Neuroblastoma (N2a) Cells, Sitao Veronica Brownheim Mar 2011

Characterization And In Vitro Toxicity Of Copper Nanoparticles (Cu-Nps) In Murine Neuroblastoma (N2a) Cells, Sitao Veronica Brownheim

Theses and Dissertations

Nanomaterials, classified as materials within the 1 - 100 nanometer range, have seemingly endless applications. It is very important to the Air Force to increase the understanding of Cu-NPs and the possible health impacts from nanomaterial exposure prior to wide-spread industry and military use. Therefore, the purpose of this research is to thoroughly characterize the properties of three different copper samples upon suspension into aqueous solutions over time: Cu-NPs (Cu 25 nm), CuO-NPs (CuO 40 nm), and Cu-MSP (Cu 500nm). Additionally, this research seeks to observe in vitro effects upon murine neuroblastoma cells (N2A) by these three types of particles …

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Multiple Integrated Navigation Sensors For Improving Occupancy Grid Fastslam, Christopher P. Weyers Mar 2011

Multiple Integrated Navigation Sensors For Improving Occupancy Grid Fastslam, Christopher P. Weyers

Theses and Dissertations

An autonomous vehicle must accurately observe its location within the environment to interact with objects and accomplish its mission. When its environment is unknown, the vehicle must construct a map detailing its surroundings while using it to maintain an accurate location. Such a vehicle is faced with the circularly defined Simultaneous Localization and Mapping (SLAM) problem. However difficult, SLAM is a critical component of autonomous vehicle exploration with applications to search and rescue. To current knowledge, this research presents the first SLAM solution to integrate stereo cameras, inertial measurements, and vehicle odometry into a Multiple Integrated Navigation Sensor (MINS) path. …

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Memristive Properties Of Thin Film Cuprous Oxide, Brett C. Castle Mar 2011

Memristive Properties Of Thin Film Cuprous Oxide, Brett C. Castle

Theses and Dissertations

Memristive properties of thin film copper oxides with different grain sizes were characterized using tunneling atomic force microscopy (TUNA) and optical reflection measurements. The thin films containing copper ions of different chemical states were prepared by thermal oxidation of metallic copper thin films, deposited via magnetron sputtering onto silicon wafer substrates at an elevated temperature for various lengths of time. The TUNA measurements showed a memristive hysteresis in the I-V curves under an applied bias profile with an initial bias of -3.5V, a ramp up to 3.5V, and subsequent return to -3.5V. Histogram analysis of the barrier height distribution for …

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Neutron Detection Using Gadolinium-Based Diodes, Benjamin R. Thomas Mar 2011

Neutron Detection Using Gadolinium-Based Diodes, Benjamin R. Thomas

Theses and Dissertations

P-n heterojunction diodes consisting of a thin n-type layer of Gd2O3 deposited on both p-type Si and p-type 4H SiC substrates were explored as possible solid-state neutron detectors. 79 keV internal conversion electrons from the de-excitation of the meta-stable Gd-158 nucleus can create ionization in the depletion region of the reverse-biased diodes resulting in a detectable signal. The diodes were modeled with Davinci software to determine the feasibility of signal detection above the reverse-bias leakage current. A CASINO simulation showed that less than one percent of the internal conversion electrons deposit their full energy within the achievable …

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