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Full-Text Articles in Engineering

Test 2219: John Deere 7r 290, Nebraska Tractor Test Lab Jan 2020

Test 2219: John Deere 7r 290, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

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Test 2221: John Deere 7r 330, Nebraska Tractor Test Lab Jan 2020

Test 2221: John Deere 7r 330, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

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Test 2223: John Deere 8r 370, Nebraska Tractor Test Lab Jan 2020

Test 2223: John Deere 8r 370, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

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Test 2224: John Deere 8r 410, Nebraska Tractor Test Lab Jan 2020

Test 2224: John Deere 8r 410, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

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Test 2228: John Deere 8rx 410, Nebraska Tractor Test Lab Jan 2020

Test 2228: John Deere 8rx 410, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

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Nebraska Summary 1197: John Deere 6195m Ft4, Nebraska Tractor Test Lab Jan 2020

Nebraska Summary 1197: John Deere 6195m Ft4, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

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Nebraska Summary 1196: John Deere 6175m Ft4, Nebraska Tractor Test Lab Jan 2020

Nebraska Summary 1196: John Deere 6175m Ft4, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

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Comparative Scoping Study Report For The Extraction Of Microalgae Oils From Two Subspecies Of Chlorella Vulgaris, Jasmine Kreft, Eric Moe, Nicholas Garcia, Andrew Ross, Wayne Seames Jan 2020

Comparative Scoping Study Report For The Extraction Of Microalgae Oils From Two Subspecies Of Chlorella Vulgaris, Jasmine Kreft, Eric Moe, Nicholas Garcia, Andrew Ross, Wayne Seames

Chemistry Faculty Publications

The production of microalgae as a fatty acid oil resource for use in biofuels production is a widespread research topic at the lab scale. Microalgae contain a higher lipid content on a dry-weight basis compared to oilseeds such as soybeans. Additionally, the growth and cultivation cycle of microalgae is 15 days, in comparison to soybeans, for which the cycle occurs once or twice annually. However, to date, it has been uneconomical to produce microalgae oils in a world-scale facility due to limitations in cultivating microalgae at commercial scales. Recent developments suggest that the use of heterotrophic microalgae may be economically …

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A Review Of Emotion Sensing: Categorization Models And Algorithms, Zhaoxia Wang, Seng-Beng Ho, Erik Cambria Jan 2020

A Review Of Emotion Sensing: Categorization Models And Algorithms, Zhaoxia Wang, Seng-Beng Ho, Erik Cambria

Research Collection School Of Computing and Information Systems

Sentiment analysis consists in the identification of the sentiment polarity associated with a target object, such as a book, a movie or a phone. Sentiments reflect feelings and attitudes, while emotions provide a finer characterization of the sentiments involved. With the huge number of comments generated daily on the Internet, besides sentiment analysis, emotion identification has drawn keen interest from different researchers, businessmen and politicians for polling public opinions and attitudes. This paper reviews and discusses existing emotion categorization models for emotion analysis and proposes methods that enhance existing emotion research. We carried out emotion analysis by inviting experts from …

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Effect Of Turbulence Model Closure Coefficient Uncertainty On Scramjet Flow Field Analysis, Martin Albert Di Stefano Jan 2020

Effect Of Turbulence Model Closure Coefficient Uncertainty On Scramjet Flow Field Analysis, Martin Albert Di Stefano

Doctoral Dissertations

“The numerical modeling of supersonic combustion ramjet (scramjet) engine flow paths plays an important role in the design of hypersonic air-breathing propulsion systems. Due to the complexity of the flow field physics and limited experimental data, numerical models possess uncertainties which should be addressed to improve the prediction accuracy of the simulations. In this study, the effect of turbulence model closure coefficient uncertainty on the Reynolds-averaged Navier-Stokes solution of a scramjet isolator and scramjet strut fuel injector flow field is investigated with an uncertainty quantification and sensitivity analysis study for commonly used turbulence models. Turbulence models considered in this work …

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Monte Carlo Simulations Of Coupled Transient Seepage Flow And Compressive Stress In Levees, Fred Thomas Tracy, Ghada Ellithy, Jodi L. Ryder, Martin T. Schultz, Benjamin R. Breland, T. Chris Massey, Maureen K. Corcoran Jan 2020

Monte Carlo Simulations Of Coupled Transient Seepage Flow And Compressive Stress In Levees, Fred Thomas Tracy, Ghada Ellithy, Jodi L. Ryder, Martin T. Schultz, Benjamin R. Breland, T. Chris Massey, Maureen K. Corcoran

Publications

The purpose of this research is to compare the results from two different computer programs of flow analyses of two levees at Port Arthur, Texas where rising water of a flood from Hurricane Ike occurred on the levees. The first program (Program 1) is a two-dimensional (2-D) transient finite element program that couples the conservation of mass flow equation with accompanying hydraulic boundary conditions with the conservation of force equations with accompanying x and y displacement and force boundary conditions, thus yielding total head, x displacement, and y displacement as unknowns at each finite element node. The second program (Program …

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Airport Operations Delays And Possible Mitigation Through Electric Taxi Systems: A Qualitative Case Study, David Cross, Kristine Kiernan, Mark Scharf Ph.D. Jan 2020

Airport Operations Delays And Possible Mitigation Through Electric Taxi Systems: A Qualitative Case Study, David Cross, Kristine Kiernan, Mark Scharf Ph.D.

Publications

Airline daily departures, not including private aircraft, increased from 25,143 in 2000 to 36,722 in 2017. More passengers necessitate more aircraft and more flights. With more aircraft at terminals, ground delays, based on current airport design, will continue to increase. Systems that allow for reduced aircraft time on the ground will improve airline economics and airport operations, in addition, will reduce airline delays both for departure and arrival at the gate. The purpose of this qualitative research study was to explore the efficacy, from ramp controllers’ perspectives, of equipping airliners with an electric taxi system. Prototype electric taxi systems have …

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Coverage Guided Differential Adversarial Testing Of Deep Learning Systems, Jianmin Guo, Houbing Song, Yue Zhao, Yu Jiang Jan 2020

Coverage Guided Differential Adversarial Testing Of Deep Learning Systems, Jianmin Guo, Houbing Song, Yue Zhao, Yu Jiang

Publications

Deep learning is increasingly applied to safety-critical application domains such as autonomous cars and medical devices. It is of significant importance to ensure their reliability and robustness. In this paper, we propose DLFuzz, the coverage guided differential adversarial testing framework to guide deep learing systems exposing incorrect behaviors. DLFuzz keeps minutely mutating the input to maximize the neuron coverage and the prediction difference between the original input and the mutated input, without manual labeling effort or cross-referencing oracles from other systems with the same functionality. We also design multiple novel strategies for neuron selection to improve the neuron coverage. The …

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Implementing The Repairer Human Factors Safety Reporting System Through Mrm (Mxhf) To Meet Sms Compliance In Aviation Maintenance, Mark D. Miller, Bettina Mrusek Jan 2020

Implementing The Repairer Human Factors Safety Reporting System Through Mrm (Mxhf) To Meet Sms Compliance In Aviation Maintenance, Mark D. Miller, Bettina Mrusek

Publications

Reiterating the importance of having a human factor related safety reporting system for aviation maintenance to reduce human error and utilizing it to gain SMS compliance, the REPAIRER method of identifying and reporting human factors hazards in aviation maintenance is reintroduced. How and why the REPAIRER method system is of such importance in the implementation of aviation maintenance safety programs can be linked to the success and evolution of maintenance resource management and human factors programs which have been effective in reducing human error in aviation maintenance. These programs are rooted in effective communication methods, as well as the identification …

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Repairer Reporting System User Analysis For Sms Compliance In Aviation Maintenance, Mark D. Miller, Bettina Mrusek Jan 2020

Repairer Reporting System User Analysis For Sms Compliance In Aviation Maintenance, Mark D. Miller, Bettina Mrusek

Publications

To resolve the issue of human error in maintenance the REPAIRER reporting system is revisited as it has great potential by combining a human factors analysis with a risk management safety reporting mechanism. It is also timely as a human factors centered safety reporting method like the REPAIRER could now be feasibly implemented through the new mandatory FAA (Federal Aviation Administration) FAR 121 requirement to use SMS (Safety Management System) pillars and through the new FAA MxHF human factors training. With the current FAA support in place and the ever growing need to add human factors to combat human error …

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Assessing Cognitive Processing And Human Factors Challenges In Nextgen Air Traffic Control Tower Team Operations, Mark D. Miller, Sam Holley, Bettina Mrusek, Linda Weiland Jan 2020

Assessing Cognitive Processing And Human Factors Challenges In Nextgen Air Traffic Control Tower Team Operations, Mark D. Miller, Sam Holley, Bettina Mrusek, Linda Weiland

Publications

Previous research of Terminal Radar Control Facilities and Standard Terminal Automation Replacement Systems interactions by the authors examined how combined NextGen digitized technology affects air traffic controller functions. Applying their updated SHELL model, human factors implications on the Tower Team before and after implementing NextGen technology were examined, focusing on cognitive loading and automated functions affecting each team member. A survey examined where cognitive difficulties occur when controllers are responsible for multiple screen views, remote airfields or helipads, and digitized cameras and blind spots. Scanning challenges were identified where local traffic, ground operations, and data converge onto one screen, and …

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Physiological Effects During Aerobatic Flights On Science Astronaut Candidates, Pedro Llanos, Diego M. Garcia Jan 2020

Physiological Effects During Aerobatic Flights On Science Astronaut Candidates, Pedro Llanos, Diego M. Garcia

Publications

Spaceflight is considered the last frontier in terms of science, technology, and engineering. But it is also the next frontier in terms of human physiology and performance. After more than 200,000 years humans have evolved under earth’s gravity and atmospheric conditions, spaceflight poses environmental stresses for which human physiology is not adapted. Hypoxia, accelerations, and radiation are among such stressors, our research involves suborbital flights aiming to develop effective countermeasures in order to assure sustainable human space presence. The physiologic baseline of spaceflight participants is subject to great variability driven by age, gender, fitness, and metabolic reserve. The objective of …

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Suborbital Payload Testing Aboard Level 3 Rocket Research Platform, Pedro Llanos, Sathya Gangadharan, Nikita Amberkar, Isachi Halphen, Melisa Mastroliberti, Michelle Munasinghe Jan 2020

Suborbital Payload Testing Aboard Level 3 Rocket Research Platform, Pedro Llanos, Sathya Gangadharan, Nikita Amberkar, Isachi Halphen, Melisa Mastroliberti, Michelle Munasinghe

Publications

Embry-Riddle Aeronautical University (ERAU) has launched several suborbital scientific payloads aboard Blue Origin’s New Shepard in 2017 and 2019. Students continue gaining hands-on experience in rocket design and construction, and payload integration and testing of future and more mature payloads to be launched into space. A Level 3 Rocket is being designed and developed at ERAU to serve as a scaled-down model research platform for launching and testing of payloads that will be later flown in commercial suborbital platforms such as Blue Origin’s New Shepard and PLD space Miura 1 rockets. Computer simulations were conducted to calculate the key parameters …

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Physiological Effects On Scientist Astronaut Candidates: Hypobaric Training Assessment, Pedro Llanos, Diego Garcia Jan 2020

Physiological Effects On Scientist Astronaut Candidates: Hypobaric Training Assessment, Pedro Llanos, Diego Garcia

Publications

This paper is addressed to expanding our understanding of the effects of hypoxia training on our bodies to better model its dynamics and leverage some of its implications and effects on human health. Hypoxia training is a recommended practice for military and civilian pilots that allow them to recognize their early hypoxia signs and symptoms, and Scientist Astronaut Candidates (SACs) who underwent hypobaric hypoxia (HH) exposure as part of a training activity for prospective suborbital flight applications. This observational-analytical study describes physiologic responses and symptoms experienced by a SAC group before, during and after HH exposure and proposes a model …

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A Framework For A Successful Additive Repair System, Todd E. Sparks Jan 2020

A Framework For A Successful Additive Repair System, Todd E. Sparks

Doctoral Dissertations

“The goal of this research is to generate a revolutionary improvement to the usability and usefulness of additive repair technology by integrating a set of tools into a seamless work flow. Insufficient automation in the current repair process is a huge hurdle in achieving cost-effective, reliable repairs. Many opportunities have been missed due to inconsistency, quality issues and lack of robustness and flexibility. The present work addresses deficiencies in preparatory steps such as 2D and 3D geometry processing, parameter estimation, and path planning as well as on-machine execution of the path plan. The bulk of the effort is focused on …

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Minimizing The Detrimental Effects Of Hydro-Peaking On Riverbank Instability: The Lower Osage River Case, Wesam Sameer Mohammed-Ali Jan 2020

Minimizing The Detrimental Effects Of Hydro-Peaking On Riverbank Instability: The Lower Osage River Case, Wesam Sameer Mohammed-Ali

Doctoral Dissertations

"The fluctuation of water level downstream from dams due to hydropower flow releases negatively affects the riverbank stability. Therefore, this research aims to examine the feasibility of using an optimization technique to mitigate the riverbank instability resulting from the outflow variation of hydropower plants. The effects of the water releases from the Bagnell Dam were investigated by computing a series of safety factors for 78 cross sections along the 81-mile stretch of the lower Osage River in relation to outflow events by using the integrated BSTEM model incorporated into the HEC-RAS model. The 1-D sediment transport and unsteady flow in …

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Impact Of Turbulence Models And Shape Parameterization On Robust Aerodynamic Shape Optimization, Aslihan Vuruskan Jan 2020

Impact Of Turbulence Models And Shape Parameterization On Robust Aerodynamic Shape Optimization, Aslihan Vuruskan

Doctoral Dissertations

"Aerodynamic design optimization is typically performed at fixed flight conditions, without considering the variation and uncertainty in operating conditions. The objective of robust aerodynamic optimization is to design an aerodynamic configuration, which will keep its optimum performance under varying conditions such as the speed of aircraft. The primary goal of this study was to investigate the impact of turbulence models used in RANS simulations on the 2-D airfoil and 3-D wing designs obtained with gradient-based deterministic and robust optimization in transonic, viscous, turbulent flows. The main contribution of this research to the aerodynamic design area was to quantify the impact …

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Iterative Optical Diffraction Tomography For Reconstruction Of Multiply-Scattering Objects, Shengli Fan Jan 2020

Iterative Optical Diffraction Tomography For Reconstruction Of Multiply-Scattering Objects, Shengli Fan

Electronic Theses and Dissertations, 2020-2023

As a label-free, non-destructive, high-resolution, and quantitative imaging technique, optical diffraction tomography (ODT) has been widely used to image biological samples and microstructures, such as cells, tissues, and optical fibers. The refractive-index (RI) distribution of an object is reconstructed from multi-view measurements of diffracted fields emerging from the object. Typical ODT setups include the object rotating configuration (ORC) and the illumination scanning configuration (ISC). One major limitation of ODT is that it is only applicable to weakly-scattering objects. In this dissertation, novel methods have been developed to overcome the reconstruction difficulty caused by multiple scattering, so as to extend ODT …

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Parallelized X-Ray Tracing With Gpu Ray-Tracing Engine, Joseph Ulseth Jan 2020

Parallelized X-Ray Tracing With Gpu Ray-Tracing Engine, Joseph Ulseth

Electronic Theses and Dissertations, 2020-2023

X-ray diffraction tomography (XDT) is used to probe material composition of objects, providing improved contrast between materials compared to conventional transmission based computed tomography (CT). In this work, a small angle approximation to Bragg's Equation of diffraction is coupled with parallelized computing using Graphics Processing Units (GPUs) to accelerate XDT simulations. The approximation gives rise to a simple yet useful proportionality between momentum transfer, radial distance of diffracted signal with respect to incoming beam's location, and depth of material, so that ray tracing may be parallelized. NVIDIA's OptiX ray-tracing engine, a parallelized pipeline for GPUs, is employed to perform XDT …

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Nonlinear Optical Mechanisms In Semiconductors And Enhanced Nonlinearities At Epsilon-Near-Zero, Sepehr Ahmadzadeh Benis Jan 2020

Nonlinear Optical Mechanisms In Semiconductors And Enhanced Nonlinearities At Epsilon-Near-Zero, Sepehr Ahmadzadeh Benis

Electronic Theses and Dissertations, 2020-2023

Light does not interact with itself in linear optical materials. Such interactions occur only in non-linear optical (NLO) materials and typically require high intensity optical beams to be signifi-cant. The ever-increasing role of NLO, where intense light may change the properties of the me-dium, has created a pressing demand to invent materials for achieving more efficient light-light and light-matter interaction due to their potential capacity to augment and possibly replace cur-rent technologies with more efficient devices. There are numerous applications of NLO devices in fundamental science, technology, health, and defense such as all-optical computation and sig-nal processing, ultrashort laser technology, …

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Selective Subtraction: An Extension Of Background Subtraction, Adeel Bhutta Jan 2020

Selective Subtraction: An Extension Of Background Subtraction, Adeel Bhutta

Electronic Theses and Dissertations, 2020-2023

Background subtraction or scene modeling techniques model the background of the scene using the stationarity property and classify the scene into two classes of foreground and background. In doing so, most moving objects become foreground indiscriminately, except for perhaps some waving tree leaves, water ripples, or a water fountain, which are typically "learned" as part of the background using a large training set of video data. Traditional techniques exhibit a number of limitations including inability to model partial background or subtract partial foreground, inflexibility of the model being used, need for large training data and computational inefficiency. In this thesis, …

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Pervasive Spectrum Sharing For Improved Wireless Experience, Mostafizur Rahman Jan 2020

Pervasive Spectrum Sharing For Improved Wireless Experience, Mostafizur Rahman

Electronic Theses and Dissertations, 2020-2023

Spectrum sharing among cellular users has been a promising approach to attain better efficiency in the use of the limited spectral bands. The existing dynamic spectrum access techniques include sharing of the licensed spectrum bands by allowing other 'secondary' users to use the bands if the licensee 'primary' user is idle. This primary-secondary spectrum sharing is limited in terms of design space, and may not be sufficient to meet the ever-increasing demand of connectivity and high signal quality to improve the end-users' wireless experience. The next step to increase spectrum efficiency is to design markets where sharing takes place pervasively …

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A Mixed Method Analysis Of Factors Influencing Success And Failure In Undergraduate Engineering Capstone Design Experiences, Kurt Stresau Jan 2020

A Mixed Method Analysis Of Factors Influencing Success And Failure In Undergraduate Engineering Capstone Design Experiences, Kurt Stresau

Electronic Theses and Dissertations, 2020-2023

The engineering undergraduate curriculum presents substantial opportunities for improvement. Society is calling for a transformation. As the culminating experience for undergraduate engineering students, capstone design team projects represent a window on the curriculum and a particularly fertile ground for understanding these opportunities. However, the factors that influence success and failure in capstone remains an area of inquiry. The work presented here proposes to help us develop a deeper understanding of these factors. The research presented here uses a mixed methods analysis approach for identifying the critical factors impacting capstone design team success, where success is defined from both student and …

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Seismic Design Optimization Of Steel Structures Using Genetic Algorithm, Tiancheng Wang Jan 2020

Seismic Design Optimization Of Steel Structures Using Genetic Algorithm, Tiancheng Wang

Electronic Theses and Dissertations, 2020-2023

Current seismic codes do not incorporate a well-established methodology for the selection of passive dampers type and their topological distribution and properties along the height of structures. Achieving the intended performance is made more complicated when structures are subject to extreme events and operate well within their inelastic range. This thesis utilizes a self-organizing genetic algorithm (soGA) with probabilistic gene-by-gene crossover and an adaptive active ground motion subset scheme to efficiently find optimal designs of low-rise steel frames subject to large number of extreme ground motions. Different types of passive dampers were considered, while the steel frames were modeled using …

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Operability And Wave Characterization Of Hydrogen And Oxygen Fed Rotating Detonation Rocket Engine, Robert Burke Jan 2020

Operability And Wave Characterization Of Hydrogen And Oxygen Fed Rotating Detonation Rocket Engine, Robert Burke

Electronic Theses and Dissertations, 2020-2023

Recently, novel experimental evidence of continuous rotating detonations for gaseous H2/O2 propellants with a rotating detonation rocket engine (RDRE) was attained on the 3-inch Air Force Research Laboratory (AFRL) Distribution A RDRE, with the fuel and oxidizer injectors modified for H2/O2 gas propellants. Evident in previous experiments, detonation instabilities arising from upstream deflagration, from recirculation zones, and from insufficient gas mixing challenged resolution of detonation wave behavior from back-end imaging with the available optical equipment. Images were often over-illuminated from both the high amount of deflagration in the plume and the higher density of detonation waves in the annulus coupled …

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