Digital Commons Network^™

Visualization Of Real-Time Displacement Time History Superimposed With Dynamic Experiments Using Wireless Smart Sensors And Augmented Reality, Marlon Frank Agüero Injante

Civil Engineering ETDs

Wireless Smart Sensor (WSS) process field data and inform structural field engineers and owners about the infrastructure health, condition, and safety. Engineers acquire the data and investigate changes on displacements under loads to make informed choices and prioritize decisions concerning maintenance, required repairs, and infrastructure replacements. However, reliable data collection and access to displacement information in the field in real-time under loads remains a challenge. The displacement data provided by the WSS in the field undergoes additional processing, and it is seen at a different location, at the decision-making headquarters. If inspectors were able to observe structural displacements in real-time …

Probing The Impacts Of Ultra-Low Platinum Loadings On Membrane Degradation Mechanisms, Andre J. Spears

Nanoscience and Microsystems ETDs

Membrane chemical degradation is one of many factors that can impact fuel cell durability. The fuel cell’s performance and lifetime heavily depends on the membrane and its ability to maintain chemical and mechanical integrity. In Nafion^® membranes, hydroxyl radicals are the primary cause of chemical membrane degradation as they attack the membrane’s polymer structure. Radical formation can ensue via peroxide decomposition at the cathode or gases reacting on Pt particles or contaminants like Fe (a fenton's reagent) within the membrane. As radicals attack the membrane’s polymer structure the membrane thins, and fluoride and sulfate ions are released. This consequently …

Intelligent Networks For High Performance Computing, William Whitney Schonbein

Computer Science ETDs

There exists a resurgence of interest in `smart' network interfaces that can operate on data as it flows through a network. However, while smart capabilities have been expanding, what they can do for high-performance computing (HPC) is not well-understood. In this work, we advance our understanding of the capabilities and contributions of smart network interfaces to HPC. First, we show current offloaded message demultiplexing can mitigate (but not eliminate) overheads incurred by multithreaded communication. Second, we demonstrate current offloaded capabilities can be leveraged to provide Turing complete program execution on the interface. We elaborate with a framework for offloading arbitrary …

Copper Electrodeposition In Full Wafer Thickness Through-Silicon Vias, Rebecca P. Schmitt

Chemical and Biological Engineering ETDs

Through-silicon vias (TSVs) are a key interconnect technology for advanced packaging of microelectronic devices, and full wafer thickness TSVs are required for certain microelectromechanical systems (MEMS) applications. In this work, electrolytes containing copper sulfate, an acid, chloride, and Tetronic 701 suppressor were implemented for Cu filling of high aspect ratio (10:1), full wafer thickness TSVs. For each electrolyte system, rotating disk electrode voltammetry was used to identify a voltage range for bottom-up Cu filling in the TSVs. Die level feature filling was performed using voltage ramping, which moved active deposition through the vias to yield void-free Cu features. During voltage-controlled …

Understanding The Role Of Atom Trapping In The Evolution Of Hydrocarbon Transformation Catalyst Morphology, Griffin Canning

Chemistry and Chemical Biology ETDs

Converting alkanes to other, more chemically and economically valuable molecules requires catalysts that can survive elevated temperatures and highly reducing environments. These environments can cause many metal-nanoparticle based catalysts to sinter rapidly, causing a loss of activity. They must also tolerate the coke formation, as well, since coke can restrict access to active sites by gas phase molecules, thus lowering catalytic activity. While there are routes to improve both the sinter and coke resistance of catalysts, an alternative strategy is to develop a protocol for regenerating the activity of the catalyst in question when coke formation or sintering becomes problematic. …

Performance Improvements For Next Generation Falling Particle Receiver Systems, Nathan R. Schroeder

Mechanical Engineering ETDs

Falling particle receiver (FPR) systems are a rapidly developing technology for concentrating solar power applications. Solid particles are used as both the heat transfer fluid and thermal energy storage media. Through the direct solar irradiation of the solid particles, flux and temperature limitations of tube-bundle receives can be overcome leading to higher operating temperatures and energy conversion efficiencies. Particle residence time, curtain opacity, and curtain stability affect the performance of FPR designs. As the particles fall through the receiver the curtain accelerates, increasing its transmissivity thus decreasing the amount of energy absorbed. Multistage release trough structures catch and release the …

Theoretical And Experimental Studies Of The Emission Of Electromagnetic Radiation By Superluminal Polarization Currents, Andrea Caroline Schmidt-Zweifel

Electrical and Computer Engineering ETDs

Maxwell’s equations establish that patterns of electric charges and currents can be animated to travel faster than the speed of light in vacuo, c, and that these superluminal distribution patterns emit tightly focused packets of electromagnetic radiation that are fundamentally different from the emissions by previously known sources -- on Earth and in the Universe. This dissertation introduces a practical faster-than-light emitter: The superluminal polarization current antenna. Such devices use a polarization current that travels faster than c to give rise to electromagnetic radiation, a technique known as the vacuum Čerenkov effect. In what is to follow, the theoretical and …

Chemical Interfacial Reactions Affecting The Speciation And Solubility Of Uranium In Organic-Rich Environments, Carmen A. Velasco

Civil Engineering ETDs

The aim of this dissertation was to investigate the interfacial reactions between uranium (U) and natural organic matter NOM) affecting the solubility, adsorption, and precipitation of U in organic-rich environments. The chemical interactions between U and NOM are not well understood, which justified the following research objectives: 1) Identify the effect of pH on U speciation and the organic functional chemistry in mineralized deposits from the Jackpile Mine.; 2) Identify the precipitation of U(VI) and NOM as a function of pH (2, 4 and 7); 3) Identify changes in DOM chemistry due to the reaction of NOM and U at …

Atom Trapping And Its Role On The Nucleation & Growth Of Platinum Nanoparticles, Deepak Kunwar

Chemistry and Chemical Biology ETDs

Diesel oxidation catalysts deactivate due to Pt sintering, a major problem in automotive industries. To make sure they operate effectively throughout the lifetime of the vehicle, automotive industries are putting an excessive amount of Pt. There is a need to develop a catalyst that serves long term performance with minimal use of Pt. Jones et al^.1 demonstrated that ceria traps Pt atoms. His work generated some logical and valid questions such as what is the mechanism for the formation of anomalously large Pt particles? What is the upper limit of Pt metal loading in the form of single atoms …

Radial Basis Densities And The Density Functional-Based Atom-In-Molecule: Designing Charge-Transfer Potentials, Godwin Amo-Kwao

Nanoscience and Microsystems ETDs

Classical potentials that are capable of describing charge transfer and charge polarization in complex systems are of central importance for classical atomistic simulation of biomolecules and materials. Current potentials—regardless of the system—do not generalize well, and, with the exception of highly-specialized empirical potentials tuned for specific systems, cannot describe chemical bond formation and breaking. The charge-transfer embedded atom method (CT-EAM), a formal, DFT-based extension to the original EAM for metals, has been developed to address these issues by modeling charge distortion and charge transfer in interacting systems using pseudoatom building blocks instead of the electron densities of isolated atoms. CT-EAM …

Integrating Deep Learning And Augmented Reality To Enhance Situational Awareness In Firefighting Environments, Manish Bhattarai

Electrical and Computer Engineering ETDs

We present a new four-pronged approach to build firefighter's situational awareness for the first time in the literature. We construct a series of deep learning frameworks built on top of one another to enhance the safety, efficiency, and successful completion of rescue missions conducted by firefighters in emergency first response settings. First, we used a deep Convolutional Neural Network (CNN) system to classify and identify objects of interest from thermal imagery in real-time. Next, we extended this CNN framework for object detection, tracking, segmentation with a Mask RCNN framework, and scene description with a multimodal natural language processing(NLP) framework. Third, …

Evaluating Public Transit Accessibility In Albuquerque, New Mexico: A Fixed-Route Bus Service Analysis, Risa E. Gutierrez

Civil Engineering ETDs

This research analyzed how residential accessibility to fixed-route bus service in Albuquerque, New Mexico varies by distance, income level, and headway. A literature review investigated components of travel that might deter people from using public transit such as travel distance, sidewalk condition or availability, bus headway, lack of active travel in today’s society, personal and traffic safety, and access equity. Geographic Information System (GIS) mapping was used to determine if low-income neighborhoods have better or worse access to ABQ Ride bus stops relative to medium- or high-income neighborhoods. Residential land use was divided into three economic classes based on 2018 …

Health Monitoring Using Deep Learning Of Acoustic And Speech Signals, Eric E. Hamke

Electrical and Computer Engineering ETDs

The focus of the research is to identify stress markers in a firefighter's speech. These markers include changes in breathing patterns and changes in the fundamental frequency of an individual’s voice. The breathing patterns are characterized using the number of breaths taken in a minute and the time spent inhaling. These measures are estimated using a Restricted Boltzmann Machine to process a firefighters’ SCBA regulator sounds, as open and closed. The classifications are then combined into continuous intervals. Observing the length of the intervals and the number of interval-starts represents time spent inhaling and the breathing rates (breaths per minute). …

Thermal Mapping And Evaporation Estimation Of Cochiti Lake Using Landsat 8 Imagery, Claudia Jimenez Arellano

Civil Engineering ETDs

Satellite remote sensing (RS) techniques have revolutionized the study of spatial and temporal processes in environmental science and water resources engineering. This study was focused on advancing the understanding of RS techniques to provide estimates of spatial variability of surface water temperature and corresponding evaporation rates for open water.

Evaporation plays a crucial role in water budgets, which is critical knowledge for water management, especially in arid environments. However, there are few methods to estimate its spatial variability, which is relevant because water does not evaporate equally everywhere on a large waterbody. Hence, we cannot assume the calculations of evaporations …

Blockchain Based Communication Architectures With Applications To Private Security Networks, Ashley N. Mayle

Computer Science ETDs

Existing communication protocols in security networks are highly centralized. While this naively makes the controls easier to physically secure, external actors require fewer resources to disrupt the system because there are fewer points in the system can be interrupted without the entire system failing. We present a solution to this problem using a proof-of-work-based blockchain implementation built on MultiChain. We construct a test-bed network containing visual imagers and microwave sensor information. These data types are ubiquitous in perimeter security systems and allow a realistic representation of a real-world network architecture. The cameras in this system use an object detection algorithm …

Gan Nanowire Laser For A Universal Atomic Force Microscope Probe: A Computational And Feasibility Study, Neal Wostbrock

Nanoscience and Microsystems ETDs

This thesis attempts to establish the groundwork for integrating a GaN nanowire into an AFM probe resulting in a universal atomic force microscope probe. Previous studies have shown GaN nanowires have stable mechanical properties, can be fabricated at scale with high aspect ratios and very smooth side walls, and have intrinsic lasing capabilities; however, mechanical and lasing capabilities have not yet been integrated into a single AFM probe. Here, we develop and analyze a suspended waveguide optical pumping concept that can be fabricated and applied to an AFM probe cantilever, unlocking full potential of GaN’s optical and mechanical properties as …

Incentivization In Mobile Edge Computing Using A Full Bayesian Approach, Sean Lebien

Electrical and Computer Engineering ETDs

The advances of multi-access edge computing (MEC) have paved the way for the integration of the MEC servers, as intelligent entities into the Internet of Things (IoT) environment as well as into the 5G radio access networks. In this thesis, a novel artificial intelligence-based MEC servers’ activation mechanism is proposed, by adopting the principles of Reinforcement Learning (RL) and Bayesian Reasoning. The considered problem enables the MEC servers’ activation decision-making, aiming at enhancing the reputation of the overall MEC system, as well as considering the total computing costs to serve efficiently the users’ computing demands, guaranteeing at the same time …

Artificial Intelligence Enabled Distributed Edge Computing For Internet Of Things Applications, Georgios Fragkos

Electrical and Computer Engineering ETDs

Artificial Intelligence (AI) based techniques are typically used to model decision-making in terms of strategies and mechanisms that can conclude to optimal payoffs for a number of interacting entities, often presenting competitive behaviors. In this thesis, an AI-enabled multi-access edge computing (MEC) framework is proposed, supported by computing-equipped Unmanned Aerial Vehicles (UAVs) to facilitate Internet of Things (IoT) applications. Initially, the problem of determining the IoT nodes optimal data offloading strategies to the UAV-mounted MEC servers, while accounting for the IoT nodes’ communication and computation overhead, is formulated based on a game-theoretic model. The existence of at least one Pure …

Prefilling Mylar Capacitor Edge Margins To Improve Capacitor Reliability And Size, Chase Kayser

Mechanical Engineering ETDs

Typical high-voltage, wound film-foil capacitors have large edge margins filled with air to prevent breakdown between foil electrodes. This arrangement is inefficient for energy density and leaves a volume where particulates may settle in an uncontrolled atmosphere. The reliability and size of high-voltage, wound film-foil capacitors could be improved by adding a material with higher breakdown strength into the edge margins. This will not only improve reliability and size but also act as a barrier to prevent foreign object debris (FOD), volatile organic compounds (VOCs), and water from damaging the capacitor’s performance. This paper will discuss the process of determining …

Plasmon-Induced Color And Photochemistry, Paul J. Gieri

Nanoscience and Microsystems ETDs

In recent decades, metallic nanostructures have been extensively studied for a variety of applications due to the ability to support surface plasmons. These excitations, which consist of collective resonant oscillations of the conduction electrons, couple strongly to visible light, confining it into subwavelength volumes. In the first part of this work, we study the optical response of metallic nanostructures supported by metallic substrates. We demonstrate that these systems support a charge transfer plasmon mode, whose frequency is primarily determined by the geometry of the contact area between the nanoparticle and the substrate. In the following part, we exploit this knowledge …

Effect Of Membrane Aging And Operating Conditions On The Rejection Of Trace Organics For Potable Reuse, Jose Pedro Hernandez

Civil Engineering ETDs

The aim of this study is to provide a better understanding of the effect that membrane degradation and operating conditions have on the removal of selected organic compounds via reverse osmosis (RO). Originally, the study included laboratory experiments in which ESPA2-LD membranes from Hydranautics were to be chemically damaged and the passage of the suite of trace organics through the membranes was to be evaluated. Unfortunately, the degradation experiments were cut short due to lab closures associated with the COVID-19 pandemic. The study then changed direction to provide insight into the role operating conditions have on the removal of trace …

Socio-Physical Human Orchestration In Smart Cities, Nathan Patrizi

Electrical and Computer Engineering ETDs

In this thesis, we present a novel socio-physical human orchestration framework to deal with the increasing complexity of smart city environments, by capitalizing on recent advances in game theory and reinforcement learning, with the goal of solving the efficient management of a smart city while improving the quality of life for the humans living in said smart city. This problem has become more challenging as the smart cities have become more complicated and complex with new technologies. In the proposed framework, each human selects a Point of Interest (PoI) that it wants to visit. This selection is performed by acting …

A Novel Framework Using Neutrosophy For Integrated Speech And Text Sentiment Analysis, Florentin Smarandache, Kritika Mishra, Ilanthenral Kandasamy, Vasantha Kandasamy W.B.

Branch Mathematics and Statistics Faculty and Staff Publications

With increasing data on the Internet, it is becoming difficult to analyze every bit and make sure it can be used efficiently for all the businesses. One useful technique using Natural Language Processing (NLP) is sentiment analysis. Various algorithms can be used to classify textual data based on various scales ranging from just positive-negative, positive-neutral-negative to a wide spectrum of emotions. While a lot of work has been done on text, only a lesser amount of research has been done on audio datasets. An audio file contains more features that can be extracted from its amplitude and frequency than a …

A Two-Dimensional Spherical-Polar Multigroup Discrete Ordinates Code For Atmospheric Particle Transport, Daniel T. Wakeford

Nuclear Engineering ETDs

A natural coordinate system for calculating neutral particle propagation in the atmosphere due to point sources is two-dimensional spherical-polar coordinates. Deterministic methods for solving the transport equation in this coordinate system require some interesting implementation details stemming from the two angular derivatives present in this form of the equation. In this dissertation, we present a bilinear discontinuous spatial discretization of the transport equation in this coordinate system. The weighted diamond difference discretization is applied to the angular derivative term in two angular dimensions, using zero-weighted starting directions to start the differencing. To our knowledge, the only previous deterministic code that …

Introducing The Self-Cleaning Filtration For Water Quality Sensors (Sc-Flawless) System, Aashish Sanjay Khandelwal

Civil Engineering ETDs

Sensor-based, semi-continuous observations of water quality parameters have become critical to understanding how changes in land use, management, and rainfall-runoff processes impact water quality at diurnal to multi-decadal scales. While some commercially available water quality sensors function adequately under a range of turbidity conditions, other instruments, including those used to measure nutrient concentrations, cease to function in high turbidity waters (> 100 NTU) commonly found in large rivers, arid-land rivers, and coastal areas. This is particularly true during storm events, when increases in turbidity are often concurrent with increases in nutrient transport. Here, we present the development and validation of …

Dectin-1 Mediated Mechanical Force Generation In Candida Albicans Fungal Pathogen Recognition, Rohan Choraghe

Biomedical Engineering ETDs

Candida spp. pathogens continue to be a major health care burden with high mortality and exceeding a billion dollars in terms of healthcare cost. Candidainfection ranges from superficial dermatological infection to more serious blood stream infection in debilitated patients. One of the major lines of innate immune defense against Candidais phagocytosis. Dectin-1 is the antifungal receptor in myeloid cells responsible for most immune responses against fungi including phagocytosis. We looked into the signaling pathway coordinating this mechanical process downstream of Dectin-1. We found that Dectin-1 activation gives rise to a significant mechanical force generation mediated through RHOA-ROCK-MyosinII pathway. …

The Investigation Of Surface Structures On Various Pathogens And Their Interactions With The Human Immune System, Carmen M. Villalobos

Biomedical Engineering ETDs

The cell surface is the first interface the host immune system encounters and

its investigation has led to a better understanding of cellular biology and types of

pathways that pathogens target in a host cell. The cell surface has evolved to include

many functions such as manipulation of the cytoskeleton, cell signaling, membrane

trafficking, adhesion, and integration into host tissue. The pathogens of interest are

the pathogenic fungus, Candida albicans, and the parasite, Giardia lamblia and we

investigate the consequences of drug treatments on the cell surface, leading to

promising new targets.

Intelligent Algorithm For Trapezoidal Interval Valued Neutrosophic Network Analysis, Florentin Smarandache, Said Broumi, Deivanayagampillai Nagarajan, Malayalan Lathamaheswari, Mohamed Talea, Assia Bakali

Branch Mathematics and Statistics Faculty and Staff Publications

The shortest path problem has been one of the most fundamental practical problems in network analysis. One of the good algorithms is Bellman-Ford, which has been applied in network, for the last some years. Due to complexity in the decision-making process, the decision makers face complications to express their view and judgment with an exact number for single valued membership degrees under neutrosophic environment. Though the interval number is a special situation of the neutrosophic, it did not solve the shortest path problems in an absolute manner. Hence, in this work, the authors have introduced the score function and accuracy …

Secondary Electron Yield Measurements On Materials Of Interest To Vacuum Electron Communication Devices, Talal Ahmed Malik

Electrical and Computer Engineering ETDs

Microwave vacuum electron devices are a critical part of communication satellite payloads. The phenomenon of multipactor breakdown (MPB) can cause the performance of these devices to deteriorate, including their partial or total destruction. MPB depends on a number of factors, including the secondary electron yield (SEY) of materials used within the device. The process of electron multiplication, which leads to breakdown, initiates with the impact of primary electrons on target surfaces, and the resonance of free electrons within an oscillating electromagnetic field under vacuum conditions. Therefore, it is of interest to find materials and surface treatment methods that exhibit low …

"A Comparison Of Variable Selection Methods Using Bootstrap Samples From Environmental Metal Mixture Data", Paul-Yvann Djamen

Mathematics & Statistics ETDs

In this thesis, I studied a newly developed variable selection method SODA, and three customarily used variable selection methods: LASSO, Elastic net, and Random forest for environmental mixture data. The motivating datasets have neuro-developmental status as responses and metal measurements and demographic variables as covariates. The challenges for variable selections include (1) many measured metal concentrations are highly correlated, (2) there are many possible ways of modeling interactions among the metals, (3) the relationships between the outcomes and explanatory variables are possibly nonlinear, (4) the signal to noise ratio in the real data may be low. To compare these methods …