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Full-Text Articles in Engineering

Development And Validation Of Improved Live Load Distribution Factors For Moment In Press-Brake-Formed Steel Tub Girder Bridges, Brook Teklu Woldegabriel Jan 2023

Development And Validation Of Improved Live Load Distribution Factors For Moment In Press-Brake-Formed Steel Tub Girder Bridges, Brook Teklu Woldegabriel

Graduate Theses, Dissertations, and Problem Reports (ETD)

Press-brake-formed tub girders (PBFTGs) offer innovative solutions for short-span steel bridge applications, possessing efficiency, versatility, and sustainability. These girders are galvanized shallow trapezoidal boxes fabricated from cold-bent structural steel plates. Depending on the design requirements, a concrete deck or other deck options, such as a steel sandwich plate system, can be placed on the girders. The Short Span Steel Bridge Alliance (SSSBA) extensively researched the steel PBFTG bridge system. As a testament to its potential, the AASHTO Innovation Initiative (AII) recognized it as a 2021 Focus Technology. AII has shown commitment to promoting the adoption of PBFTG among its member …


Localization Of People In Gnss-Denied Environments Using Neural-Inertial Prediction And Kalman Filter Correction, Lauren N. Cash Jan 2023

Localization Of People In Gnss-Denied Environments Using Neural-Inertial Prediction And Kalman Filter Correction, Lauren N. Cash

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis presents a method based on neural networks and Kalman filters for estimating the position of a person carrying a mobile device (i.e., cell phone or tablet) that can communicate with static UWB sensors or is carried in an environment with known landmark positions. This device is used to collect and share inertial measurement unit (IMU) information — which includes data from sensors such as accelerometers, gyroscopes, and magnetometers — and UWB and landmark information. The collected data, in combination with other necessary initial condition information, is input into a pre-trained deep neural network (DNN) which predicts the movement …


Application Of The Flowing Material Balance To Unconventional Gas Reservoirs, Amanda Jo Parrish Jan 2023

Application Of The Flowing Material Balance To Unconventional Gas Reservoirs, Amanda Jo Parrish

Graduate Theses, Dissertations, and Problem Reports (ETD)

In the realm of conventional reservoirs, the estimation of Original Gas-in-Place (OGIP) has long been established using traditional material balance method. However, the emergence of unconventional shale reservoirs accessed through horizontal well and hydraulic fracturing presents new challenges for estimation OGIP by the traditional material balance. The flowing material balance (FMB) has the potential to provide an estimate of the OGIP in the stimulated reservoir volume (SRV).

Adsorption of hydrocarbons to the organic matter within the shale rock matrix represents a significant component of the overall OGIP. The inclusion of the Langmuir volume and pressure in the material balance equation …


Manganese-Based A-Site High-Entropy Perovskite Oxides For Solar Thermochemical Hydrogen Production, Cijie Liu Jan 2023

Manganese-Based A-Site High-Entropy Perovskite Oxides For Solar Thermochemical Hydrogen Production, Cijie Liu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Non-stoichiometric perovskite oxides have been studied as a new family of redox oxides for solar thermochemical hydrogen (STCH) production owing to their favourable thermodynamic properties. However, conventional perovskite oxides suffer from limited phase stability and kinetic properties, and poor cyclability. Here, we report a strategy of introducing A-site multi-principal-component mixing to develop a high-entropy perovskite oxide, (La1/6Pr1/6Nd1/6Gd1/6Sr1/6Ba1/6)MnO3 (LPNGSB_Mn), which shows desirable thermodynamic and kinetics properties as well as excellent phase stability and cycling durability. LPNGSB_Mn exhibits enhanced hydrogen production (~77.5 mmol moloxide–1) compared to (La …


Exploiting The Advantages And Overcoming The Challenges Of The Cable In A Tethered Drone System, Rogerio Rodrigues Lima Jan 2023

Exploiting The Advantages And Overcoming The Challenges Of The Cable In A Tethered Drone System, Rogerio Rodrigues Lima

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation proposes solutions for motion planning, localization, and landing of tethered drones using only tether variables. A tether-based multi-model localization framework for tethered drones is proposed. This framework comprises three independent localization strategies based on a different model. The first strategy uses simple trigonometric relations assuming that the tether is taut; the second method relies on a set of catenary equations for the slack tether case; the third estimator is a neural network-based predictor that can cover different tether shapes. Multi-layer perceptron networks previously trained with a dataset comprised of the tether variables (i.e., length, tether angles on the …


Implementing Test Automation With Selenium Webdriver, Ramana Inturi Jan 2023

Implementing Test Automation With Selenium Webdriver, Ramana Inturi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Many software programs, such as applications for designing, modeling, simulating, and analyzing systems, are now commonly available as web-based applications. The testing of such sophisticated web applications is highly challenging and can be extremely tedious and error-prone if done manually. Recently automation tools have become increasingly used for testing web-based applications, as they minimize human involvement and repetitive work.

For this problem report project, we have built and implemented an automation testing framework for web applications. The project specifically uses a tool called Selenium WebDriver, which has been used to develop the testing framework. By using this framework, testers may …


Improving The Health And Safety Of Manufacturing Workers By Detecting And Addressing Personal Protective Equipment (Ppe) Violations In Real-Time With The Use Of Automated Ppe Detection Technology, Joseph Olufemi Fasinu Jan 2023

Improving The Health And Safety Of Manufacturing Workers By Detecting And Addressing Personal Protective Equipment (Ppe) Violations In Real-Time With The Use Of Automated Ppe Detection Technology, Joseph Olufemi Fasinu

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Centers for Disease Control and Prevention (CDC) emphasized that Personal Protective Equipment (PPE) can significantly reduce the risk of occupational injuries and illnesses. However, improper use, failure to use, and other PPE-related violations can still result in injuries and fatalities. Eye and face protection violation has been one of the top 10 most frequently violated OSHA standards in fiscal years 2018, 2019, 2020, 2021 and 2022 consecutively. A common practice among safety professionals to ensure PPE compliance has been to physically inspect or monitor PPE usage among workers, which has been found to be unsustainable on a continuous real-time …


Spatio-Temporal Deep Learning Approaches For Addressing Track Association Problem Using Automatic Identification System (Ais) Data, Md Asif Bin Syed Jan 2023

Spatio-Temporal Deep Learning Approaches For Addressing Track Association Problem Using Automatic Identification System (Ais) Data, Md Asif Bin Syed

Graduate Theses, Dissertations, and Problem Reports (ETD)

In the realm of marine surveillance, track association constitutes a pivotal yet challenging task, involving the identification and tracking of unlabelled vessel trajectories. The need for accurate data association algorithms stems from the urge to spot unusual vessel movements or threat detection. These algorithms link sequential observations containing location and motion information to specific moving objects, helping to build their real-time trajectories. These threat detection algorithms will be useful when a vessel attempts to conceal its identity. The algorithm can then identify and track the specific vessel from its incoming signal. The data for this study is sourced from the …


Development Of A Quasi-Dimension Gci Combustion Model Aided By Cfd, Jinsu Kim Jan 2023

Development Of A Quasi-Dimension Gci Combustion Model Aided By Cfd, Jinsu Kim

Graduate Theses, Dissertations, and Problem Reports (ETD)

Advanced combustion strategies have been proposed to improve fuel efficiency while minimizing exhaust emissions. Gasoline compression ignition (GCI) combustion featuring partially premixed compression ignition (PPCI) and diffusion combustion has been recognized as an attractive, viable combustion strategy for its potential and advantages over conventional diesel and gasoline engines. The optimization of the GCI engine system requires the development of a quasi-dimensional GCI combustion model capable of simulating GCI combustion while requesting less computational burden than CFD simulation, which is very critical in engine system simulation. This study developed a quasi-dimension, phenomenological combustion model for PPCI and diffusion combustion to facilitate …


Robust State Estimation Methods For Robotics Applications, Shounak Das Jan 2023

Robust State Estimation Methods For Robotics Applications, Shounak Das

Graduate Theses, Dissertations, and Problem Reports (ETD)

State estimation is an integral component of any autonomous robotic system. Finding the correct position, velocity, and orientation of an agent in its environment enables it to do other tasks like mapping and interacting with the environment, and collaborating with other agents. State estimation is achieved by using data obtained from multiple sensors and fusing them in a probabilistic framework. These include inertial data from Inertial Measurement Unit (IMU), images from camera, range data from lidars, and positioning data from Global Navigation Satellite Systems (GNSS) receivers. The main challenge faced in sensor-based state estimation is the presence of noisy, erroneous, …


System Analysis Of An Internal Combustion Engine (Ice) – Solid Oxide Fuel Cell (Sofc) Hybrid Cycle, Jose Javier Colon Rodriguez Jan 2023

System Analysis Of An Internal Combustion Engine (Ice) – Solid Oxide Fuel Cell (Sofc) Hybrid Cycle, Jose Javier Colon Rodriguez

Graduate Theses, Dissertations, and Problem Reports (ETD)

Due to the intermittent nature of renewable energy and the rigid operation of existing coal plants, the need for flexible power generation technology is eminent. Hybrid energy systems have shown potential for flexible, grid following dynamics while maintaining higher efficiencies. The work below focuses on the performance analysis of a proposed 100 kW pressurized Internal Combustion Engine (ICE) and Solid Oxide Fuel Cell (SOFC) hybrid system. The un-utilized fuel from the SOFC stack provided the chemical energy to operate the engine. A turbocharger was used to deliver the necessary air flow for both the stack and engine. An external reformer …


Motion Planning In Artificial And Natural Vector Fields, Bernardo Martinez Rocamora Junior Jan 2023

Motion Planning In Artificial And Natural Vector Fields, Bernardo Martinez Rocamora Junior

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation advances the field of autonomous vehicle motion planning in various challenging environments, ranging from flows and planetary atmospheres to cluttered real-world scenarios. By addressing the challenge of navigating environmental flows, this work introduces the Flow-Aware Fast Marching Tree algorithm (FlowFMT*). This algorithm optimizes motion planning for unmanned vehicles, such as UAVs and AUVs, navigating in tridimensional static flows. By considering reachability constraints caused by vehicle and flow dynamics, flow-aware neighborhood sets are found and used to reduce the number of calls to the cost function. The method computes feasible and optimal trajectories from start to goal in challenging …


Material Characterization Of Thermoplastic Polyurethane (Tpu) And Thermoplastic Elastomers (Tpe) For Development Of 3d-Printed Surrogate Organs For Medical Training, Anastasia Elizabeth Lucci Jan 2023

Material Characterization Of Thermoplastic Polyurethane (Tpu) And Thermoplastic Elastomers (Tpe) For Development Of 3d-Printed Surrogate Organs For Medical Training, Anastasia Elizabeth Lucci

Graduate Theses, Dissertations, and Problem Reports (ETD)

Cadaveric specimens are a necessary, albeit limited, resource for training medical students on basic surgical skills. The availability of surrogate 3D-printed organs would readily allow access to resources that could reduce or potentially eliminate the need for cadaveric specimens or, at a minimum, provide students the opportunity to practice with 3D-printed surrogates before transitioning to those specimens. This research focuses on determining which thermoplastic material most closely mimics mechanical properties such as hardness and stiffness of human organs and allows 3D printing surrogate organs to be used as safe, educational tools. Relatively “soft” materials such as thermoplastic polyurethanes (TPU) and …


Modular Supply Network Optimization Of Renewable Ammonia And Methanol Co-Production, Benjamin Akoh Jan 2023

Modular Supply Network Optimization Of Renewable Ammonia And Methanol Co-Production, Benjamin Akoh

Graduate Theses, Dissertations, and Problem Reports (ETD)

To reduce the use of fossil fuels and other carbonaceous fuels, renewable energy sources such as solar, wind, geothermal energy have been suggested to be promising alternative energy that guarantee sustainable and clean environment. However, the availability of renewable energy has been limited due to its dependence on weather and geographical location. This challenge is intended to be solved by the utilization of the renewable energy in the production of chemical energy carriers. Hydrogen has been proposed as a potential renewable energy carrier, however, its chemical instability and high liquefaction energy makes researchers seek for other alternative energy carriers. Ammonia …


Impacts Of Diverse Inflammatory Stimuli On Neutrophil Behavior: Extracellular Vesicles, E-Cigarettes, And Nanoparticles, Hunter T. Snoderly Jan 2023

Impacts Of Diverse Inflammatory Stimuli On Neutrophil Behavior: Extracellular Vesicles, E-Cigarettes, And Nanoparticles, Hunter T. Snoderly

Graduate Theses, Dissertations, and Problem Reports (ETD)

Neutrophils are the body’s front-line defenders against foreign insult and are key players in a variety of inflammatory conditions. This body of work examines the role of neutrophils in promoting pathology in three distinct inflammatory contexts. In the pro-inflammatory state provoked by breast cancer, neutrophils decondense their nuclei and release cytotoxic web-like structures known as neutrophil extracellular traps (NETs). NETs form most commonly via histone modifications facilitated by the enzyme PAD4. NETs are known to be a harbinger of disease progression and promote metastasis through capture of circulating tumor cells. It was hypothesized that breast tumors release small particles known …


Energy Digital Twins In Smart Manufacturing Systems, Anna Billey Jan 2023

Energy Digital Twins In Smart Manufacturing Systems, Anna Billey

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this thesis, an Energy Digital Twin for smart manufacturing systems was developed and evaluated. In particular, the study focused on bidirectional parameter communication between the physical and the virtual part with the aim of optimizing the energy used in the manufacturing process. Rising costs and the environmental impacts related to energy consumption have grown in importance worldwide. There are elevated concerns in sectors like manufacturing, leading to an urgent quest to reduce energy consumption. A recent advancement in Industry 4.0 technology, the Digital Twin, represents a promising smart technology and tool that researchers are investigating to help reduce energy …


Simulations Of Implementation Of Advanced Communication Technologies, Ivy Yousuf Moutushi Jan 2023

Simulations Of Implementation Of Advanced Communication Technologies, Ivy Yousuf Moutushi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Wireless communication systems have seen significant advancements with the introduction of 3G, 4G, and 5G mobile standards. Since the simulation of entire systems is complex and may not allow evaluation of the impact of individual techniques, this thesis presents techniques and results for simulating the performance of advanced signaling techniques used in 3G, 4G, and 5G systems, including Code division multiple access (CDMA), Multiple Input Multiple Output (MIMO) systems, and Low-Density Parity Check (LDPC) codes. One implementation issue that is explored is the use of quantized Analog to Digital Converter (ADC) outputs and their impact on system performance.

Code division …


Lithium-Ion Battery Safety Analysis With Physical Sub-Models, Samuel Abimbola Ogunfuye Jan 2023

Lithium-Ion Battery Safety Analysis With Physical Sub-Models, Samuel Abimbola Ogunfuye

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ever-increasing explosions occurring globally at a rapid rate and in diverse situations have re-established the fact that novel, faster, and more accurate approaches must be developed to analyze and possibly curb these explosions and avert their future occurrences. Experimental endeavors and computational fluid dynamics (CFD) simulations as compared to engineering models generally require enormous time, and resources, as well as a high-level of expertise and technicalities. This might, however, delay prompt analysis and the ability to draw conclusions, thereby causing setbacks in recommending safety measures for different situations and conditions. Therefore, robust models which are accurate and fast to give …


Spin Recovery Analysis On A Simulation Model Of The Nasa F-18 High Alpha Research Vehicle (Harv) Using Thrust Vectoring, Brock M. Dolly Jan 2023

Spin Recovery Analysis On A Simulation Model Of The Nasa F-18 High Alpha Research Vehicle (Harv) Using Thrust Vectoring, Brock M. Dolly

Graduate Theses, Dissertations, and Problem Reports (ETD)

In the early years of aviation, spins were poorly understood and frequently fatal. With just over a century of research and experiments dedicated to spins, today’s aviation world has a very firm grasp on spin aerodynamics. Most fighter aircraft have airframes and control surfaces specifically designed to ensure the ability of departure from the possible spin modes the aircraft can enter. An alternative and/or additional approach is given by thrust vectoring. Implementing thrust vectoring into spin recovery can potentially save an aircraft and/or the life of the pilot in situation where control-surface-only spin recovery is not able to recover the …


Weigh-In-Motion Data-Driven Pavement Performance Prediction Models, Mohhammad Afsar Sujon Jan 2023

Weigh-In-Motion Data-Driven Pavement Performance Prediction Models, Mohhammad Afsar Sujon

Graduate Theses, Dissertations, and Problem Reports (ETD)

The effective functioning of pavements as a critical component of the transportation system necessitates the implementation of ongoing maintenance programs to safeguard this significant and valuable infrastructure and guarantee its optimal performance. The maintenance, rehabilitation, and reconstruction (MRR) program of the pavement structure is dependent on a multidimensional decision-making process, which considers the existing pavement structural condition and the anticipated future performance. Pavement Performance Prediction Models (PPPMs) have become indispensable tools for the efficient implementation of the MRR program and the minimization of associated costs by providing precise predictions of distress and roughness based on inventory and monitoring data concerning …


Analysis Of The Psychological And Production Effects Of The Use Of Gamification For Manufacturing Assembly, Makenzie Dolly Jan 2023

Analysis Of The Psychological And Production Effects Of The Use Of Gamification For Manufacturing Assembly, Makenzie Dolly

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this dissertation, the applications of gamification for manufacturing with a focus on effects to workers and productivity were studied. Gamification is a relatively new research area, with the term being officially defined in 2010. Since then, several fields (education, health, and marketing) have benefitted from its application. Despite exhibiting strong potential, the application of gamification had remained rather unexplored in the manufacturing domain. To explore this further, by employing a comprehensive literature review, four research gaps were identified: the need for i) the use and acceptance of Deterding’s definition of gamification, ii) a clearer definition for various game element …


Spatiotemporal Trends In Particle-Associated Microbial Communities In A Chlorinated Drinking Water Distribution System, Madison Haddix Jan 2023

Spatiotemporal Trends In Particle-Associated Microbial Communities In A Chlorinated Drinking Water Distribution System, Madison Haddix

Graduate Theses, Dissertations, and Problem Reports (ETD)

Bacteria can survive treatment and enter drinking water distribution systems (DWDSs), or enter DWDSs through intrusion or maintenance work on the system. DWDSs can also be suitable environments for bacterial regrowth. Many factors can affect the microbial community composition of DWDSs, including various spatiotemporal, hydraulic, and water quality parameters. Although most bacteria within DWDSs are harmless, opportunistic pathogens, such as Legionella pneumophila, Pseudomonas aeruginosa, and Mycobacterium avium, can inhabit DWDSs and premise plumbing and are the leading cause of waterborne disease outbreaks in developed countries. Previous studies have attempted to establish relationships between various parameters and microbial …


Ambient Ammonia Synthesis Via Microwave-Catalytic Materials And Plasma Chemistry, Siobhan Brown Jan 2023

Ambient Ammonia Synthesis Via Microwave-Catalytic Materials And Plasma Chemistry, Siobhan Brown

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ammonia is critical to supporting human life on earth because of its use as fertilizer. The Haber-Bosch process to produce ammonia has been practiced for over 100 years. This process operates at high pressure and temperature to overcome the thermodynamic and kinetic limitations of the ammonia synthesis reaction thus researchers have tried to overcome it for decades. At present this process represents 1% of global energy usage and 2.5% of global CO2 emissions. The proposed chemical looping ammonia synthesis approach seeks to reduce the environmental impact of this critical process and to elucidate microwave-catalytic principles.

This research aims to …


Optimal Design And Operation Of Integrated Hydrogen Generation And Utilization Plants, Ijiwole Solomon Ijiyinka Jan 2023

Optimal Design And Operation Of Integrated Hydrogen Generation And Utilization Plants, Ijiwole Solomon Ijiyinka

Graduate Theses, Dissertations, and Problem Reports (ETD)

There are considerable efforts worldwide for reducing the use of fossil fuel for energy production. While renewable energy sources are being increasingly used, fossil fuel still contribute about 80% of the energy used worldwide. As a result, the level of CO2 is still increasing fast in the atmosphere currently exceeding about 410 parts per million (ppm). For reducing CO2 build up in the atmosphere, various approaches are being investigated. For the electric power generation sector, two key approaches are post-combustion CO2 capture and use of hydrogen as a fuel for power generation. These two solutions can also …


Feasibility Of Applying Motion Magnification In Subsurface Defect Detection For Concrete And Fiber-Reinforced Polymer Specimens, Nagavardhani Malineni Jan 2023

Feasibility Of Applying Motion Magnification In Subsurface Defect Detection For Concrete And Fiber-Reinforced Polymer Specimens, Nagavardhani Malineni

Graduate Theses, Dissertations, and Problem Reports (ETD)

Irrespective of size and complexity, every civil infrastructure needs certain scrutiny regarding its structural health to ensure its serviceability during its lifetime. In olden times such scrutiny was done with the aid of destructive testing methods using sensors that required cumbersome and expensive installations and led to the destruction of at least part of the tested specimen. However, in recent times, many non-destructive methods, such as acoustic emission testing, electromagnetic testing, and laser testing methods have emerged, leaving the specified tested specimen undisturbed. With the advancement in sensor technology like motion magnification and with the help of access to high-speed …


A Machine Learning Approach For Early Diagnosis Of Transthyretin Amyloid Cardiomyopathy Among Heart Failure Patients, Tanjim Ahmed Jan 2023

A Machine Learning Approach For Early Diagnosis Of Transthyretin Amyloid Cardiomyopathy Among Heart Failure Patients, Tanjim Ahmed

Graduate Theses, Dissertations, and Problem Reports (ETD)

Transthyretin Amyloid Cardiomyopathy (ATTR-CM) is a rare, progressive, and fatal disease. Prevalence of ATTR-CM ranges from 4 to 17 per 100000 cases where the mean survival time is less than 4 years. It has a history of being underdiagnosed and misdiagnosed. The diagnosis delay has a weighted mean of 6.1 years for wild-type ATTR-CM. Low awareness, the necessity of invasive procedures, and lack of treatment are the key reasons for delayed diagnosis. But, with the introduction of non-invasive tests like nuclear scintigraphy with 99mTC-PYP and the disease modifying drug Tafamidis, the diagnosis delay signifies a missed opportunity to increase …


State Estimation, Covariance Estimation, And Economic Optimization Of Semi-Batch Bioprocesses, Ronald Hunter Alexander Jan 2023

State Estimation, Covariance Estimation, And Economic Optimization Of Semi-Batch Bioprocesses, Ronald Hunter Alexander

Graduate Theses, Dissertations, and Problem Reports (ETD)

One of the most critical aspects of any chemical process engineer is the ability to gather, analyze, and trust incoming process data as it is often required in control and process monitoring applications. In real processes, online data can be unreliable due to factors such as poor tuning, calibration drift, or mechanical drift. Outside of these sources of noise, it may not be economically viable to directly measure all process states of interest (e.g., component concentrations). While process models can help validate incoming process data, models are often subject to plant-model mismatches, unmodeled disturbances, or lack enough detail to track …


Methane Emissions Produced By Pneumatic Devices And Produced Water Tanks On Natural Gas Wellsites, Benjamin William Thornton Jan 2023

Methane Emissions Produced By Pneumatic Devices And Produced Water Tanks On Natural Gas Wellsites, Benjamin William Thornton

Graduate Theses, Dissertations, and Problem Reports (ETD)

Abstract

Methane Emissions Produced by Pneumatic Devices and Produced Water Tanks on Natural Gas Wellsites

Benjamin W. Thornton

In recent years, more scrutiny has been placed on the release of greenhouse gasses (GHGs) by the oil and gas industry in North America as climate concerns increase. In the coming years, stricter regulations proposed by the Environmental Protection Agency (EPA) concerning the release of GHGs will further direct attention to GHG emissions quantification, modeling, and overall reduction. Active natural gas wellsites employ production equipment that routinely emits methane during normal operation. Production equipment often includes, but is not limited to, gas …


Development Of A Framework To Support Community-Scale Nutrient Recovery For Local Crop Fertilization And Production, Scott A. Lopez Jan 2023

Development Of A Framework To Support Community-Scale Nutrient Recovery For Local Crop Fertilization And Production, Scott A. Lopez

Graduate Theses, Dissertations, and Problem Reports (ETD)

Nutrient and resource recovery (NRR) has become increasingly crucial as regions face deteriorating sanitation infrastructures, limited support, and growing environmental challenges. Implementing region-specific NRR technologies and systems could provide effective circular economy insights into addressing these challenges. Because of the multidisciplinary challenges associated with the design and implementation of NRR strategies, various government and local decision-makers need to collaborate effectively in the decision-making process. Structured decision-making (SDM) methodologies are practical when determining the most appropriate NRR strategy for nutrient-rich waste streams. However, applications of computational SDM limited because of the vast amounts of data that are needed to analyze the …


Internal Surface Nanostructure And Chemistry Modification On Porous Cathode Of Solid Oxide Fuel Cell To Mitigate Cr Contamination From Interconnect, Liang Liang Jan 2023

Internal Surface Nanostructure And Chemistry Modification On Porous Cathode Of Solid Oxide Fuel Cell To Mitigate Cr Contamination From Interconnect, Liang Liang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Solid Oxide Fuel cells (SOFCs) could convert the chemical energy from a variety of fuels into electricity. It has become a competitive power source due to its advantages, such as high efficiency and flexibility in fuel options. It can be operated under a wide range of operating temperatures, which makes them easy to be applied and developed into applications. To further increase the lifetime and reduce the cost of SOFC systems to make them more competitive and affordable for commercialization, the catalytic activity for oxygen reduction reaction at the cathode needs to be improved. One significant technical opportunity is to …