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Full-Text Articles in Engineering

Hardware Development And Error Characterisation For The Afit Rail Sar System, Dayne A. Schmidt Mar 2016

Hardware Development And Error Characterisation For The Afit Rail Sar System, Dayne A. Schmidt

Theses and Dissertations

This research is focussed on updating the Air Force Institute of Technology (AFIT) Radar Instrumentation Lab (RAIL) Synthetic Aperture Radar (SAR) experimental system. Firstly, this research assesses current hardware limitations and updates the system configuration and methodology to enable collections from a receiver in motion. Secondly, orthogonal frequency-division multiplexing (OFDM) signals are used to form (SAR) images in multiple experimental and simulation configurations. This research analyses, characterises and attempts compensation of relevant SAR image error sources, such as Doppler shift or motion measurement errors (MMEs). Error characterisation is conducted using theoretical, simulated and experimental methods. Final experimental results are presented …

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Multihop Rendezvous Algorithm For Frequency Hopping Cognitive Radio Networks, John A. Pavlik Mar 2016

Multihop Rendezvous Algorithm For Frequency Hopping Cognitive Radio Networks, John A. Pavlik

Theses and Dissertations

Cognitive radios allow the possibility of increasing utilization of the wireless spectrum, but because of their dynamic access nature require new techniques for establishing and joining networks, these are known as rendezvous. Existing rendezvous algorithms assume that rendezvous can be completed in a single round or hop of time. However, cognitive radio networks utilizing frequency hopping that is too fast for synchronization packets to be exchanged in a single hop require a rendezvous algorithm that supports multiple hop rendezvous. We propose the Multiple Hop (MH) rendezvous algorithm based on a pre-shared sequence of random numbers, bounded timing differences, and similar …

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Effect Of Plug In Hybrid Electric Vehicle Adoption On Gas Tax Revenue, Local Pollution, And Greenhouse Gas Emissions, Neil Mccall Mar 2016

Effect Of Plug In Hybrid Electric Vehicle Adoption On Gas Tax Revenue, Local Pollution, And Greenhouse Gas Emissions, Neil Mccall

Theses and Dissertations

Plug-in hybrid electric vehicles (PHEV) are likely to increase in popularity in the near future. However, the environmental benefits of PHEVs involve tradeoffs between the benefits of reduced tailpipe emissions against the drawbacks of increased emissions at marginal electric generation plants and reduced gasoline tax income. In this report, a model is developed that will enable these tradeoffs to be studied. The model accounts for local commuting patterns and marginal electric generation in New Jersey. The result allows the effect of PHEV adoption on gasoline tax, CO2, NOx and SOx to be predicted on a county level. Sample calculations are …

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Associative Cad References In The Neutral Parametric Canonical Form, Daniel Robert Staves Mar 2016

Associative Cad References In The Neutral Parametric Canonical Form, Daniel Robert Staves

Theses and Dissertations

Due to the multiplicity of computer-aided engineering applications present in industry today, interoperability between programs has become increasingly important. A survey conducted among top engineering companies found that 82% of respondents reported using 3 or more CAD formats during the design process. A 1999 study by the National Institute for Standards and Technology (NIST) estimated that inadequate interoperability between the OEM and its suppliers cost the US automotive industry over $1 billion per year, with the majority spent fixing data after translations. The Neutral Parametric Canonical Form (NPCF) prototype standard developed by the NSF Center for e-Design, BYU Site offers …

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Neutral Parametric Database, Server, Logic Layers, And Clients To Facilitate Multi-Engineersynchronous Heterogeneous Cad, Kelly Eric Bowman Mar 2016

Neutral Parametric Database, Server, Logic Layers, And Clients To Facilitate Multi-Engineersynchronous Heterogeneous Cad, Kelly Eric Bowman

Theses and Dissertations

Engineering companies are sociotechnical systems in which engineers, designers, analysts, etc. use an array of software tools to follow prescribed product-development processes. The purpose of these amalgamated systems is to develop new products as quickly as possible while maintaining quality and meeting customer and market demands. Researchers at Brigham Young University have shortened engineering design cycle times through the development and use of multiengineer synchronous (MES) CAD tools. Other research teams have shortened design cycle-times by extending seamless interoperability across heterogeneous design tools and domains. Seamless multi-engineer synchronous heterogeneous (MESH) CAD environments is the focus of this dissertation. An architecture …

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In Vitro Molecular Modification Of Human Cultured And Primary Cells Using Lance Array Nanoinjection, John W. Sessions Mar 2016

In Vitro Molecular Modification Of Human Cultured And Primary Cells Using Lance Array Nanoinjection, John W. Sessions

Theses and Dissertations

Fundamentally altering cellular function at a genetic level is a major area of interest in the biologic sciences and the medical community. By engineering transfectable constructs that can be inserted to dysfunctional cellular systems, scientists can mitigate aberrant genetic behavior to produce proper molecular function. While viral vectors have been a mainstay in the past, there are many limitations, particularly related to safety, that have changed the focus of genome editing to incorporate alternative methods for gene delivery. Lance Array Nanoinjection (LAN), a second-generation microfabricated transfection biotechnology, is one of these alternative technologies. LAN works by utilizing both simultaneous electrostatic …

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Lateral Resistance Of Pipe Piles Behind A 20-Foot-Tall Mse Wall With Welded-Wire Reinforcements, Ryan Thomas Budd Mar 2016

Lateral Resistance Of Pipe Piles Behind A 20-Foot-Tall Mse Wall With Welded-Wire Reinforcements, Ryan Thomas Budd

Theses and Dissertations

Pile foundations for bridges must often resist lateral loads produced by earthquakes and thermal expansion and contraction of the superstructure. Right-of-way constraints near bridge abutments are leading to an increased use of mechanically stabilized earth (MSE) walls below the abutment. Previous research has shown that lateral pile resistance can be greatly reduced when piles are placed close to MSE walls but design codes do not address this issue. A full-scale MSE wall was constructed and 24 lateral load tests were conducted on pipe, square and H piles spaced at distances of about 2 to 5 pile diameters from the back …

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Extracellular Matrix From Whole Porcine Heart Decellularization For Cardiac Tissue Engineering, Nima Momtahan Mar 2016

Extracellular Matrix From Whole Porcine Heart Decellularization For Cardiac Tissue Engineering, Nima Momtahan

Theses and Dissertations

Heart failure is one of the leading causes of death in the United States. Every year in the United States, more than 800,000 people are diagnosed with heart failure and more than 375,000 people die from heart disease. Current therapies such as heart transplants and bioartificial hearts are helpful, but not optimal. Decellularization of porcine whole hearts followed by recellularization with patient-specific human cells may provide the ultimate solution for patients with heart failure. Great progress has been made in the development of efficient processes for decellularization, and the design of automated bioreactors. In this study, the decellularization of porcine …

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An Automated Method For Optimizing Compressor Blade Tuning, Kurt Berlin Hinkle Mar 2016

An Automated Method For Optimizing Compressor Blade Tuning, Kurt Berlin Hinkle

Theses and Dissertations

Because blades in jet engine compressors are subject to dynamic loads based on the engine's speed, it is essential that the blades are properly "tuned" to avoid resonance at those frequencies to ensure safe operation of the engine. The tuning process can be time consuming for designers because there are many parameters controlling the geometry of the blade and, therefore, its resonance frequencies. Humans cannot easily optimize design spaces consisting of multiple variables, but optimization algorithms can effectively optimize a design space with any number of design variables. Automated blade tuning can reduce design time while increasing the fidelity and …

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Maximizing Virtual Mucax Engineering Design Team Performance, Brett Randall Stone Mar 2016

Maximizing Virtual Mucax Engineering Design Team Performance, Brett Randall Stone

Theses and Dissertations

Teams of design engineers are increasingly working as members of virtual teams, or teams whose members are distributed geographically and communicate mostly through electronic means. In addition, emerging multi-user (MU) applications engage complementary teams in synchronous design activities. These new MU tools are changing the way engineers work together. Together, these factors have created a new and interesting environment in which engineering design teams must function. The work presented here lays out two major themes that teams and their managers can effectively apply to organizing and managing MU teams: 1) teams can maximize their potential productivity by determining the optimal …

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Understanding And Addressing Collaboration Challenges For The Effective Use Of Multi-User Cad, David James French Mar 2016

Understanding And Addressing Collaboration Challenges For The Effective Use Of Multi-User Cad, David James French

Theses and Dissertations

Multi-user computer-aided design (CAD) is an emerging technology that promises to facilitate collaboration, enhance product quality, and reduce product development lead times by allowing multiple engineers to work on the same design at the same time. The BYU site of the NSF Center for e-Design has developed advanced multi-user CAD prototypes that have demonstrated the feasibility and value of this technology. Despite the possibilities that this software opens up for enhanced collaboration, there are now a new variety of challenges and opportunities to understand and address. For multi-user CAD to be used effectively in a modern engineering environment, it is …

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The Influence Of Pile Shape And Pile Sleeves On Lateral Load Resistance, Dalin Newell Russell Mar 2016

The Influence Of Pile Shape And Pile Sleeves On Lateral Load Resistance, Dalin Newell Russell

Theses and Dissertations

The lateral resistance of pile foundations is typically based on the performance of round piles even though other pile types are used. Due to lack of data there is a certain level of uncertainty when designing pile foundations other than round piles for lateral loading. Theoretical analyses have suggested that square sections will have more lateral resistance due to the increased side shear resistance, no test results have been available to substantiate the contention. Full-scale lateral load tests involving pile shapes such as circular, circular wrapped with high density polyethylene sheeting, square, H, and circular with a corrugated metal sleeve …

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Decomposition Of Manufacturing Processes For Multi-User Tool Path Planning, Andrew Scherbel Priddis Mar 2016

Decomposition Of Manufacturing Processes For Multi-User Tool Path Planning, Andrew Scherbel Priddis

Theses and Dissertations

Engineering activities by nature are collaborative endeavors. Single-user applications like CAD, CAE, and CAM force a strictly serial design process, which ultimately lengthens time to market. New multi-user applications such as NXConnect address the issue during the design stage of the product development process by enabling users to work in parallel. Multi-user collaborative tool path planning software addresses the same serial limitations in tool path planning, thereby decreasing cost and increasing the quality of manufacturing processes. As part complexity increases, lead times are magnified by serial workflows. Multi-user tool path planning can shorten the process planning time. But, to be …

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A Comparison Of Instructional Strategies For Teaching Entry-Level Welding At The High School Level, Jared Paul Massic Mar 2016

A Comparison Of Instructional Strategies For Teaching Entry-Level Welding At The High School Level, Jared Paul Massic

Theses and Dissertations

The traditional method of teaching welding has remained unchanged for decades. In this model, an instructor gives demonstrations to a class of students and then helps them individually as they practice the techniques of welding. This traditional instructional method has been effective but is time consuming. Due to a significant increase in the demand for skilled welders within the United States, efforts have been made to develop more efficient methods of providing welding instruction. Various electronic welding guidance systems and virtual welding systems have recently been developed. In this study, the researcher addressed two questions 1) Does the use of …

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Simple Models For Estimating The Rotational Stiffness Of Steel Column-To-Footing Connections, Joshua Edwin Tryon Mar 2016

Simple Models For Estimating The Rotational Stiffness Of Steel Column-To-Footing Connections, Joshua Edwin Tryon

Theses and Dissertations

Despite the crucial role they play in transferring loads from the superstructure to the foundation, steel column-to-footing connections have received little attention in research. Though shallow embedded connections are typically characterized as pinned, studies have shown that they exhibit significant rotational stiffness. The objective of this thesis is to quantify the rotational stiffness of such connections. A method named the continuum model is developed by which the rotational stiffness of embedded connections may be calculated. Outputs from this model are compared with experimental data on steel connections embedded in concrete. The continuum model is shown to be capable of reasonably …

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Evaluation Of Passive Force On Skewed Bridge Abutments With Controlled Low-Strength Material Backfill, Kevin Bjorn Wagstaff Mar 2016

Evaluation Of Passive Force On Skewed Bridge Abutments With Controlled Low-Strength Material Backfill, Kevin Bjorn Wagstaff

Theses and Dissertations

Although its use has become more widespread, controlled low-strength material, or CLSM, has fallen through the crack between geotechnical engineering and materials engineering research. The National Ready Mix Association states that CLSM is not a low strength concrete, and geotechnical engineers do not consider it as a conventional aggregate backfill. The use of CLSM as a bridge abutment backfill material brings up the need to understand the passive force versus backwall displacement relationship for this application. To safely account for forces generated due to seismic activity and thermal expansion in bridge design, it is important to understand the passive force …

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Evaluation Of The Accuracy Of Approach Volume Counts And Speeds Collected By Microwave Sensors, Gregory Hans Sanchez Mar 2016

Evaluation Of The Accuracy Of Approach Volume Counts And Speeds Collected By Microwave Sensors, Gregory Hans Sanchez

Theses and Dissertations

This study evaluates the accuracy of approach volumes and free flow approach speeds collected by the Wavetronix SmartSensor Advance sensor using the field data collected by JAMAR counter boards for free flow approach volumes and a TruCam LiDAR gun for approach speeds. The Advance sensor is primarily designed for dilemma zone reduction. It does not have the capability to differentiate between lanes, but the Advance sensor currently used has a detection range of up to 600 ft. and has the capability to track vehicles approaching the intersection. The Utah Department of Transportation (UDOT) wanted to use this capability to get …

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Using Source-To-Source Transformations To Add Debug Observability To Hls-Synthesized Circuits, Joshua Scott Monson Mar 2016

Using Source-To-Source Transformations To Add Debug Observability To Hls-Synthesized Circuits, Joshua Scott Monson

Theses and Dissertations

This dissertation introduces a novel approach for exposing the internal, source-level expressions of circuits generated by high-level synthesis (HLS) for in-circuit debug. The approach uses source-to-source transformations to instrument specific source-level expressions with debug ports. These debug ports allow a user to connect a debugging instrument (e.g. an embedded logic analyzer) to record the activity of the expression corresponding to the debug port. This dissertation demonstrates that a debugging solution based on these source-to-source transformations is feasible and that individual debug ports can be added for a cost of a 1-2% increase in circuit area on average. It also introduces …

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Measuring Soft Error Sensitivity Of Fpga Soft Processor Designs Using Fault Injection, Nathan Arthur Harward Mar 2016

Measuring Soft Error Sensitivity Of Fpga Soft Processor Designs Using Fault Injection, Nathan Arthur Harward

Theses and Dissertations

Increasingly, soft processors are being considered for use within FPGA-based reliable computing systems. In an environment in which radiation is a concern, such as space, the logic and routing (configuration memory) of soft processors are sensitive to radiation effects, including single event upsets (SEUs). Thus, effective tools are needed to evaluate and estimate how sensitive the configuration memories of soft processors are in high-radiation environments. A high-speed FPGA fault injection system and methodology were created using the Xilinx Radiation Test Consortium's (XRTC's) Virtex-5 radiation test hardware to conduct exhaustive tests of the SEU sensitivity of a design within an FPGA's …

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An Analysis Of The Effectiveness Of A Multi-Disciplinary Decision Support System On System-Level Decision Making, Troy Mario Seletos Mar 2016

An Analysis Of The Effectiveness Of A Multi-Disciplinary Decision Support System On System-Level Decision Making, Troy Mario Seletos

Theses and Dissertations

Decisions Support Systems (DSSs) are used to enhance decision maker speed and effectiveness. However, without a view of an entire system, any decision may have unanticipated effects such as sub-optimal outcomes. The purpose of this research is to show that with a system-level analysis, more informed decisions can be made that take into account a larger system or greater number of dimensions or objectives. This research also explores the benefits of using a DSS over analysis of unprocessed data and the effectiveness of integrating a product design generator (PDG) with a business DSS, creating a system DSS, where system-level effects …

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Aminoacyl-Trna Synthetase Production For Unnatural Amino Acid Incorporation And Preservation Of Linear Expression Templates In Cell-Free Protein Synthesis Reactions, Andrew Broadbent Mar 2016

Aminoacyl-Trna Synthetase Production For Unnatural Amino Acid Incorporation And Preservation Of Linear Expression Templates In Cell-Free Protein Synthesis Reactions, Andrew Broadbent

Theses and Dissertations

Proteins—polymers of amino acids—are a major class of biomolecules whose myriad functions facilitate many crucial biological processes. Accordingly, human control over these biological processes depends upon the ability to study, produce, and modify proteins. One innovative tool for accomplishing these aims is cell-free protein synthesis (CFPS). This technique, rather than using living cells to make protein, simply extracts the cells' natural protein-making machinery and then uses it to produce protein in vitro. Because living cells are no longer involved, scientists can freely adapt the protein production environment in ways not otherwise possible. However, improved versatility and yield of CFPS protein …

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The Impact Of Bicycle Corridors On Travel Demand In Utah, Christopher Kent Haskell Mar 2016

The Impact Of Bicycle Corridors On Travel Demand In Utah, Christopher Kent Haskell

Theses and Dissertations

Bicycling as an alternate mode of transportation has been on the rise. It is environmentally friendly in nature and the associated health benefits have made it a popular choice for many types of trips. The purpose of this research is to increase understanding of the impacts of implementing bicycle corridors (as part of the Utah Department of Transportation's (UDOT) Inclusion of Active Transportation policy) on bicycle rate as a function of roadway characteristics. The results of this research will be used in determining when and where bicycle corridors will enhance the transportation system and an estimate of the overall impact …

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Design, Development And Testing Of Web Services For Multi-Sensor Snow Cover Mapping, Jiri Kadlec Mar 2016

Design, Development And Testing Of Web Services For Multi-Sensor Snow Cover Mapping, Jiri Kadlec

Theses and Dissertations

This dissertation presents the design, development and validation of new data integration methods for mapping the extent of snow cover based on open access ground station measurements, remote sensing images, volunteer observer snow reports, and cross country ski track recordings from location-enabled mobile devices. The first step of the data integration procedure includes data discovery, data retrieval, and data quality control of snow observations at ground stations. The WaterML R package developed in this work enables hydrologists to retrieve and analyze data from multiple organizations that are listed in the Consortium of Universities for the Advancement of Hydrologic Sciences Inc …

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Conjugate Heat Transfer And Average Versus Variable Heat Transfer Coefficients, Tyler James Macbeth Mar 2016

Conjugate Heat Transfer And Average Versus Variable Heat Transfer Coefficients, Tyler James Macbeth

Theses and Dissertations

An average heat transfer coefficient, h_bar, is often used to solve heat transfer problems. It should be understood that this is an approximation and may provide inaccurate results, especially when the temperature field is of interest. The proper method to solve heat transfer problems is with a conjugate approach. However, there seems to be a lack of clear explanations of conjugate heat transfer in literature. The objective of this work is to provide a clear explanation of conjugate heat transfer and to determine the discrepancy in the temperature field when the interface boundary condition is approximated using h_bar compared to …

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Analysis Of High Fidelity Turbomachinery Cfd Using Proper Orthogonal Decomposition, Ronald Alex Spencer Mar 2016

Analysis Of High Fidelity Turbomachinery Cfd Using Proper Orthogonal Decomposition, Ronald Alex Spencer

Theses and Dissertations

Assessing the impact of inlet flow distortion in turbomachinery is desired early in the design cycle. This thesis introduces and validates the use of methods based on the Proper Orthogonal Decomposition (POD) to analyze clean and 1/rev static pressure distortion simulation results at design and near stall operating condition. The value of POD comes in its ability to efficiently extract both quantitative and qualitative information about dominant spatial flow structures as well as information about temporal fluctuations in flow properties. Observation of the modes allowed qualitative identification of shock waves as well as quantification of their location and range of …

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Investigation Of Polyaniline And Its Composites As Interlayers In Organic Solar Cells, Omar Abdulrazzaq Al-Azzawi Feb 2016

Investigation Of Polyaniline And Its Composites As Interlayers In Organic Solar Cells, Omar Abdulrazzaq Al-Azzawi

Theses and Dissertations

Significant attention has been given during the last few years to overcoming technological and material barriers to the development of organic photovoltaic devices (OPVs) with cost efficiency comparable to that of inorganic photovoltaics (PVs). If OPVs are to become commercially viable, major improvements are necessary. In this work, polyaniline (PANI) protonated with various levels of camphorsulfonic acid (CSA) and dissolved in m-cresol has been used as a hole-transport layer (HTL) in organic bulk-heterojunction solar cells. Polyaniline was first synthesized using oxidative polymerization based on the MacDiarmid method. The polymerization parameters, such as polymerization temperature and polymerization pH control agent, were …

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Alkali Silica Reaction (Asr) Mitigation For Arkansas Region, Lois Farouk Kamel Feb 2016

Alkali Silica Reaction (Asr) Mitigation For Arkansas Region, Lois Farouk Kamel

Theses and Dissertations

The objective of this research is to mitigate and prevent the alkali silica reactivity (ASR) in highway construction projects. ASR is a deleterious reaction initiated when the silica content of the aggregate reacts with alkali hydroxides in the mix in the presence of relatively high moisture content. The ASR results in the formation of an expansive white colored gel-like material which forms the destructive tensile stresses inside hardened concrete. Different types of local aggregates available in the State of Arkansas were mixed, mortar bars and concrete specimens were poured according to the ASTM specifications. Specimens' expansion was measured versus time, …

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Development Of Lightweight Concrete Mixes For Construction Industry At The State Of Arkansas, Mohammed Abdulwahab Almansouri Feb 2016

Development Of Lightweight Concrete Mixes For Construction Industry At The State Of Arkansas, Mohammed Abdulwahab Almansouri

Theses and Dissertations

As the construction industry evolved, the need for more durable, long lasting infrastructure increased. Therefore, more efforts have been put to find new methods to improve the properties of the concrete to prolong the service life of the structural elements. One of these methods is the use of lightweight aggregate as an internal curing agent to help reducing self-desiccation and shrinkage. This research studied the effects of using locally available lightweight aggregate (expanded clay), as a partial replacement of normal weight aggregate in the concrete matrix. The concrete mixtures contained lightweight aggregate with a replacement percentage of 12.5, 25, 37.5, …

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The Influence Of Season, Heating Mode And Slope Angle On Wildland Fire Behavior, Jonathan R. Gallacher Feb 2016

The Influence Of Season, Heating Mode And Slope Angle On Wildland Fire Behavior, Jonathan R. Gallacher

Theses and Dissertations

Wildland fire behavior research in the last 100 years has largely focused on understanding the physical phenomena behind fire spread and on developing models that can predict fire behavior. Research advances in the areas of live-fuel combustion and combustion modeling have highlighted several weaknesses in the current approach to fire research. Some of those areas include poor characterization of solid fuels in combustion modeling, a lack of understanding of the dominant heat transfer mechanisms in fire spread, a lack of understanding regarding the theory of live-fuel combustion, and a lack of understanding regarding the behavior of flames near slopes. In …

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Arctic Sea Ice Classification And Soil Moisture Estimation Using Microwave Sensors, David Brian Lindell Feb 2016

Arctic Sea Ice Classification And Soil Moisture Estimation Using Microwave Sensors, David Brian Lindell

Theses and Dissertations

Spaceborne microwave sensors are capable of estimating various properties of many geophysical phenomena, including the age and extent of Arctic sea ice and the relative soil moisture over land. The measurement and classification of such geophysical phenomena are used to refine climate models, localize and predict drought, and better understand the water cycle. Data from the active Ku-band scatterometers, the Quick Scatterometer (QuikSCAT), and the Oceansat-2 Scatterometer (OSCAT), are here used to classify areas of first-year and multiyear Arctic sea ice using a temporally adaptive threshold on reported radar backscatter values. The result is a 15-year data record of daily …

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