Engineering Commons^™

Oxidized Graphitic Nano-Amendment Of Cement Composites: Exploring Truly Low Concentrations And Novel Particle Morphologies, Shohana Iffat

Theses and Dissertations

Oxidized graphitic nanoparticles such as multiwalled carbon nanotubes (MWCNTs) and graphene nanoplatelets (GNPs), can produce enhancements in physicomechanical properties of cement composites that are relevant to structural and durability performance, provided that said nanoparticles are well dispersed in the composite. Lower-bound MWCNT concentrations are reported in the literature in the range 0.01-0.05% in weight of cement (wt%). Such concentrations may not be costeffective for practical applications and may also be excessive since they would result in a nanoparticle surface area at or above 105 m2 for 1 m3 of cement paste, or 104.5 m2 for 1 m 3 of concrete, …

Knowledge-Infused Learning, Manas Gaur

Theses and Dissertations

In DARPA’s view of the three waves of AI, the first wave of AI, symbolic AI, focused on explicit knowledge. The second and current wave of AI is termed statistical AI. Deep learning techniques have been able to exploit large amounts of data and massive computational power to improve human levels of performance in narrowly defined tasks. Separately, knowledge graphs have emerged as a powerful tool to capture and exploit a variety of explicit knowledge to make algorithms better apprehend the content and enable the next generation of data processing, such as semantic search. After initial hesitancy about the scalability …

Development Of Micro-Sized Algan Deep Ultraviolet Light Emitting Diodes And Monolithic Photonic Integrated Circuits, Richard Speight Floyd Iii

Theses and Dissertations

III-Nitride materials-based visible emission LEDs have emerged as a disruptive technology in the fields of lighting,ⁱ) communications,^ii,iii,iv) and displays.^v,vi) Shorter wavelength LEDs in the DUV spectral region (210nm – 360nm) with ultra-wide bandgap (UWBG) Al_xGa_1-xN active layers are now poised to displace toxic Mercury-based light sources.^vii) Over the past decade AlGaN LEDs operating in the deep ultra-violet (DUV) spectral region (200 nm < λ_emission < 300 nm) have been deployed in novel applications including autonomous drone-based sterilization and sanitization systems, ^viii) point-of-use water purification systems, ^ix) photo-therapeutics,x) gas sensors,xi) and non-line-of-sight (NLOS) communications.^xii) Similarly, DUV light detectors using ultra-wide bandgap (UWBG) Al …

Identifying And Discovering Curve Pattern Designs From Fragments Of Pottery, Jun Zhou

Theses and Dissertations

The surface of many cultural heritage objects, such as pottery sherds found in the Southeastern Woodlands, were embellished with curve patterns. The original full designs of these patterns reflect rich historical and cultural information. However, in practice, most objects are fragmentary, making the complete underlying designs unknowable at the scale of the sherd fragment. The challenge to reconstruct and study complete designs is stymied because 1) most pottery sherds contain only a small portion of the underlying full design, 2) curve patterns detected on a sherd are usually incomplete and noisy, and 3) in the case of a stamping application, …

Nondestructive Material Characterization Using A Fully Noncontact Ultrasonic Lamb Wave System For Thin Metals, Nuclear Cladding, And Composite Materials, Elsa Z. Compton

Theses and Dissertations

Effective non-destructive evaluation (NDE) inspection system and methods are highly desired in a broad range of engineering applications including thin metal structure thickness evaluation. Ultrasonic guided waves in thin-walled structures, namely Lamb waves, have gained popularity as a NDE method. By using the ultrasonic waves in conjunction with high spatial resolution multidimensional wavefield measurements, thickness evaluations for thin metals can be achieved. This thesis explores the configuration and application of a fully noncontact ultrasonic Lamb wave NDE system for thickness characterization and evaluation of very thin metal plates. We have tested the actuation and sensing of Lamb waves for thickness …

The Effect Of Pulsed Field Dc Electrophoresis And Field Amplified Sample Stacking On The Microchip Electrophoretic Separation Of Organic Dyes, Travis Geoffrey Stewart

Theses and Dissertations

The utility of field amplified sample stacking and pulsed field electrophoresis toward improving electrophoretic outcomes was studied with regards to the electrophoretic separation of three organic dyes rhodamine B, 2’,7’-dichlorofluorescein, and fluorescein salt in microchip electrophoresis conditions. In this study, there were four experimental groups: nonstacking nonpulsed, nonstacking pulsed, sample stacking nonpulsed, and sample stacking pulsed.

Electrophoretic outcomes were evaluated by examining the electrophoretic separations under an epifluoresence detection method, plotting the signal intensities vs. time, and comparing separation resolutions and signal-to-noise ratios between experimental groups. From this it was shown that sample stacking nonpulsed conditions yielded the best outcome …

Networked Digital Predictive Control For Modular Dc-Dc Converters, Castulo Aaron De La O Pérez

Theses and Dissertations

The concept of power electronics building blocks (PEBB) has driven advancements in highly modularized converter systems with many identical subsystems. PEBBs are distributed subsets of converter systems and thus require communication with a control system for their coordination. For this type of system, the communication latency with hard deterministic deadlines is the driving attribute of communication system requirements. However, inherent communication requirements for PEBB-based converter systems also provide opportunities for coordination of energy flow.

Leveraging developments in Gigabit serial communication channels, a control and communication platform architecture for distributed control schemes based on the 2D-Torus communication network topology was developed …

Automated Contingency Management For Water Recycling System, Shijie Tang

Theses and Dissertations

NASA’s exploration program envisions the utilization of a Deep Space Habitat (DSH) for human exploration of the space environment in the vicinity of Mars and beyond. Communication latency and extreme limitations of power and life-supporting resources make it imperative to operate the DSH systems in a highly autonomous fashion. One such system is the Environmental Control and Life Support System (ECLSS) which needs to be monitored and optimized to support its designated missions.

Integrated System Health Management (ISHM) technologies have been developed in the past decades to provide a real-time assessment of system health and use this information to improve …

Changes In Drought Characteristics Under Future Climate Projections, Diogo Stalin De Alcantara Araujo

Theses and Dissertations

Accumulating evidence on the impact of climate change on droughts, highlight the necessity for developing effective adaptation and mitigation strategies. Global Drought Layers were developed for historic and future runs of nine global climate models (GCM) of the Coupled Model Intercomparison Model 6th phase (CMIP6). Relative changes of drought characteristics were estimated, and hotspots were identified, especially in South America, Africa, Europe, Western USA, and Australia. Further, changes in future drought risk and severity in Australia are quantified. Historic conditions (1981-2014) and projections for mid-century (2015-2050) and end-century (2051-2100) from four shared socioeconomic pathways (SSP1-2.6, SSP2-4.5, SSP3-7.0 and SSP5-8.5) are …

Rf-Over-Fiber Receiver Design And Link Performance Verification For Alpaca Signal Transport, Nathaniel Ray Ashcraft

Theses and Dissertations

The Advanced L-band Phased Array Camera (ALPACA) is a wide-field astronomical receiver that will be housed on the Green Bank Telescope (GBT). This instrument features a fully cryogenic 69-element phased array feed (PAF) front end and digital beamformer back end. It will provide a wide and continuous field of view at L-band and high sensitivity with a system noise temperature below 27 K. Transport of the received astronomical signals on 138 individual channels from prime focus of the GBT to the digital back end -- over a distance of 3 km -- will be provided by a custom RF-over-fiber (RFoF) …

Augmenting Heads-Up Displays With Intelligent Agents: A Human Factors Approach, Grant Edward Morfitt

Theses and Dissertations

Situational awareness, both tactical and strategic, is essential for humans engaged in complex tasks in civilian and military theaters of operation. Previous work has shown that heads-up displays are effective tools for providing critical information to operators in such situations. Hitherto, heads-up displays have been designed to relay instrument and sensor information to the operator in a topical, timely, and accurate manner. There is a large body of complementary work in the area of human factors that deals with presenting information to a user without detracting from the primary mission. This thesis investigates, measures, and validates the effectiveness of a …

Development Of Software Tools For Efficient And Sustainable Process Development And Improvement, Jake P. Stengel

Theses and Dissertations

Infrastructure is a key component in the well-being of our society that leads to its growth, development, and productive operations. A well-built infrastructure allows the community to be more competitive and promotes economic advancement. In 2021, the ASCE (American Society of Civil Engineers) ranked the American infrastructure as substandard, with an overall grade of C-. The overall ranking suffers when key infrastructure categories are not maintained according to the needs of the population. Therefore, there is a need to consider alternative methods to improve our infrastructure and make it more sustainable to enhance the overall grade. One of the challenges …

Electro-Mechanical Data Fusion For Heart Health Monitoring, Kemal Yakut

Theses and Dissertations

Heart disease is a major public health problem and one of the leading causes of death worldwide. Therefore, cardiac monitoring is of great importance for the early detection and prevention of adverse conditions. Recently, there has been extensive research interest in long-term, continuous, and non-invasive cardiac monitoring using wearable technology. Here we introduce a wearable device for monitoring heart health. This prototype consists of three sensors to monitor electrocardiogram (ECG), phonocardiogram (PCG), and seismocardiogram (SCG) signals, integrated with a microcontroller module with Bluetooth wireless connectivity. We also created a custom printed circuit board (PCB) to integrate all the sensors into …

Automated Pre-Play Analysis Of American Football Formations Using Deep Learning, Jacob Deloy Newman

Theses and Dissertations

Annotation and analysis of sports videos is a time consuming task that, once automated, will provide benefits to coaches, players, and spectators. American football, as the most watched sport in the United States, could especially benefit from this automation. Manual annotation and analysis of recorded video of American football games is an inefficient and tedious process. Currently, most college football programs focus on annotating offensive formation. As a first step to further research for this unique application, we use computer vision and deep learning to analyze an overhead image of a football play immediately before the play begins. This analysis …

Biomimetic Strategies To Control Therapeutic Release From Novel Dna Nanoparticles, Robert J. Mosley

Theses and Dissertations

The inherent chemical, mechanical, and structural properties of nucleic acids make them ideal candidates for the formulation of tunable, personalized drug nanocarriers. However, none so far have exploited these properties for the controlled release of therapeutic drugs. In this dissertation, a biomimetic approach to controlling drug release is exhibited by specifically manipulating the architecture of novel, DNA nanoparticles to take advantage of drug binding mechanisms of action. Rationally designed DNA strands were immobilized on gold surfaces via a terminal thiol modification. Immobilized monomers can be manipulated to form distinct monolayer architectures including flat, folded, coiled, or stretched structures. Increasing the …

Development Of A Covid-19 Vulnerability Index (Cvi) For The Counties And Residents Of New Jersey, Remo Victor Disalvatore

Theses and Dissertations

The COVID-19 pandemic has impacted countless aspects of everyday life since it was declared a global pandemic by the World Health Organization in March of 2020. From societal to economic impacts, COVID-19 and its variants will leave a lasting impact on our society and the world. Approximately $9 trillion has been spent on fighting the pandemic around the world. During the pandemic, it became increasingly evident that indices, such as the Center for Disease Control (CDC) Social Vulnerability Index (SVI), were extremely important for predicting vulnerabilities in a community. The CDC's SVI provides important estimates on which communities will be …

Laboratory Assessement Of Emulsion-Cement Paste And Cold Recycled Mixtures At Varying Amounts Of Emulsion, Cement, And Water, Ahmed Saidi

Theses and Dissertations

The main objective of this study was to assess the performance of cold recycled mixtures (CRMs) at: (1) binder level through evaluating the rheological and mechanical properties of emulsion-cement paste (ECP), and (2) mix level through characterizing the density and performance of CRMs. The testing program for ECPs included multiple stress creep recovery (MSCR), bending beam rheometer (BBR), linear amplitude sweep (LAS), penetration test, and isothermal calorimetry. For CRMs, a balanced mix design (BMD) approach was used to develop performance interaction charts to select optimum contents of emulsion, cement, and water maximizing the resistance of CRMs to rutting and cracking. …

Lowering The Technological Barrier In Developing, Sharing And Installing Web Gis Applications, Rohit Kumar Khattar

Theses and Dissertations

Portability of web applications between web servers of different organizations can be challenging and can complicate sharing and collaborative use of such tools. Given the distributed nature of the web, this lack of portability is usually not a concern because a user in one organization can link to and use a web application hosted by another organization. However, access control or differentiation may be needed by an organization in terms of area of interest, input data, analytical techniques, access control, presentation, branding, and language. This is true for many government organizations, and their associated web sites, and servers. In such …

Legal Characterization Of The Challenges Faced By The Construction Industry During Covid-19 And Devaluation Of The Egyptian Pound, Riham Abuzaid

Theses and Dissertations

With all the challenges this past decade has inflicted on the economy on a global scale, Egypt had its share with two major events, starting with the Egyptian pound devaluation against the U.S dollar in 2016 and currently the emergence of the COVID-19 pandemic. These major events instigated the interference of the legal/contractual sectors in the construction market to find solutions that range from agreeable to stringent to protect the assets of their beneficiaries.

Both events are impactful and require extensive analysis to determine and classify each situation. This thesis addresses the implementation of standard internationally acknowledged legislative acts used …

Machine Learning Applications To Static Timing Analysis, Waseem Mohamed Raslan

Theses and Dissertations

Modeling complex cell behavior is critical for accurate static timing analysis. Effective current source model, ECSM, and composite current source, CCS, waveform data compression became a necessity to reduce the size of technology files and increase the accuracy of the cell characterization data. We used deep learning nonlinear Autoencoders to compress voltage and current waveforms and compared them with singular value decomposition, SVD, approach. Autoencoders gave ~1.67x compression ratio for voltage waveforms better than SVD approach and gave 45x to 55x better compression ratio compared to other lossless techniques like bz2 and gzip. Autoencoders achieved ~1.7x compression ratio for complex …

An Analysis Of Groundwater Storage Loss In The Central Valley Using A Novel In Situ Method Compared To Grace-Derived Results, Michael David Stevens

Theses and Dissertations

Robust groundwater management is necessary to maintain long-term aquifer sustainability. Temporally and spatially inconsistent in situ data prevents robust groundwater resource evaluation. Data from the Gravity Recovery and Climate Experiment (GRACE) satellite mission has been used to evaluate long-term, large-scale groundwater trends. However, the spatial resolution of GRACE data presents challenges for groundwater management in medium-sized aquifers like the Central Valley of California (CV). Other researchers have utilized GRACEderived data to evaluate groundwater storage in the CV, but they often make corrections due to what is referred to as the "leakage effect." We demonstrate a method for imputing gaps in …

Investigation Of Material, Process, And Environmental Factors In Bubble Defect Formation For Labels Of Bottled Essential Oils, Joseph Lloyd Andrus

Theses and Dissertations

Labeling of consumer products is not only required by regulatory bodies for product identification, but it also serves as a symbol of product quality and prestige. Bubbles under the label are unsightly and impact customer satisfaction. Pressure Sensitive Adhesive (PSA) labels currently make up more than eighty percent of all labels in the market today, yet little research could be found addressing causes of bubbling in an industrial setting. A root cause analysis for bubble development included four aspects: label application, environmental conditions of shipping and storage, defects in glass bottle geometry, and oil contamination. The most significant findings from …

Optofluidic Manipulation With Nanomembrane Platforms Used For Solid-State Nanopore Integration, Zachary J. Walker

Theses and Dissertations

Nanopore technology has introduced new techniques for single particle detection and analysis. A nanopore consists of a small opening in a membrane on the nanometer scale. Nanopores are found in nature and are utilized for transporting molecules through biological membranes. Researchers have been able to mimic naturally forming biological nanopores and utilize them for a variety of sensing applications. Nanopores, fabricated either organically or inorganically, can be used for detecting biomarkers such as proteins, nucleic acids, and metabolites that translocate the membrane by way of the nanopore. Constant ionic current flow is measured through the nanopore by way of a …

Reformulated Vortex Particle Method And Meshless Large Eddy Simulation Of Multirotor Aircraft, Eduardo J. Alvarez

Theses and Dissertations

The vortex particle method (VPM) is a mesh-free approach to computational fluid dynamics (CFD) solving the Navier-Stokes equations in their velocity-vorticity form. The VPM uses a Lagrangian scheme, which not only avoids the hurdles of mesh generation, but it also conserves vortical structures over long distances with minimal numerical dissipation while being orders of magnitude faster than conventional mesh-based CFD. However, VPM is known to be numerically unstable when vortical structures break down close to the turbulent regime. In this study, we reformulate the VPM as a large eddy simulation (LES) in a scheme that is numerically stable, without increasing …

A Formal Consideration Of User Tactics During Product Evaluation In Early-Stage Product Development, Trenton Brady Owens

Theses and Dissertations

Frequent and effective design evaluation is foundational to the success of any product development effort. Products used, installed, or otherwise handled by humans would benefit from an evaluation of the product while formally considering both the physical embodiment of the technology, termed technology, and the steps a user should take to use that technology, termed tactics. Formal and simultaneous evaluations of both technology and tactics are not widespread in the product design literature. Although informal evaluation methods have advantages, formal methods are also known to be effective. In this paper we propose a formal method for evaluating tactics and technology …

Classification And Creation Of Design Tools And Methods For Social Impact Considerations In Engineering For Global Development, Andrew Gary Armstrong

Theses and Dissertations

Every product has economic, environmental, and social impacts whether or not those impacts are explicitly considered. These impacts affect society and are an important part of engineering design. "Triple Bottom Line Sustainability" focuses on economic, environmental, and social sustainability and has become an important goal for those designing products. Economic considerations are an established part of the engineering design process. Environmental considerations are increasingly being considered in design including the development of design standards and widely used methodologies. Social impact considerations, however, lack the standardization and wide inclusion of economic and environmental considerations. This results in reduced and unbalanced consideration …

Effects Of Tackification Agents On Room Temperature Epoxy Mechanical Properties, Garen B. Murray

Theses and Dissertations

When laying up dry composite materials and aligning the fibers in the appropriate directions it can be a challenge due to the dryness of the fiber and mold design. Several commercial products are available to help fix plies to molds keeping the proper fiber orientation depending upon mold geometry. Prepreg and wet layups do not have this problem due to the inherent inclusion of a matrix in their manufacturing, dry materials have no added epoxy at the time of layup and are therefore in need of assistance maintain position. The purpose of this research is to determine if Super 77™ …

Methods For Characterizing Groundwater Resources With Sparse In-Situ Data, Ren Nishimura

Theses and Dissertations

Groundwater water resources must be accurately characterized in order to be managed sustainably. Due to the cost to install monitoring wells and challenges in collecting and managing in-situ data, groundwater data is sparse in space and time especially in developing countries. In this study we analyzed long-term groundwater storage changes with limited times-series data where each well had only one groundwater measurement in time. We developed methods to synthetically create times-series groundwater table elevation (WTE) by clustering wells with uniform grid and k-means-constrained clustering and creating pseudo wells. Pseudo wells with the WTE values from the cluster-member wells were temporally …

Design And Control Of Modular Soft Robotic Actuators With Architected Structures, Nicholas Pagliocca

Theses and Dissertations

Soft robotic systems composed of highly compliant materials offer unparalleled advantages compared to rigid-body systems in applications such as fragile material handling and human-machine interactions. Often, their motions are prescribed by structural anisotropy and reinforcement materials to directionally limit motion. The continuum motion and non-linear material response intrinsic to soft robotics makes their design, modeling, and control a formidable challenge for engineers. Leveraging the deformation driven response of soft robotic actuators, highly versatile compliant architected structures whose local deformations dictate global material response can be integrated into soft robotic actuators for tunable mechanical responses. In this thesis, flexible center-symmetric perforated …

Progress On Static Structures In Leaky Mode Waveguides, Manusha Korimi

Theses and Dissertations

Virtual reality (VR) head-mounted displays provide a high definition, immersive experi-ence to the viewer. However, most existing technologies have flaws like bulky design and vergence-accommodation conflict that may cause stress in the neck muscles, posture issues, nausea, motion sickness and dizziness. Similarly, augmented reality (AR) displays, which use transparent light modulators, exist, but they possess low field of view and a limited number of discrete depth planes when wide field of view and continuous depth would be ideal. The ultimate goal of my research is use leaky mode waveguide devices to create wide-view angle, transparent near eye holographic displays for …