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Optimal Parameter Values For Accurate And Repeatable Nanoindentation Of Human Trabecular Bone, Stephen Matthew Kmak

Master's Theses

Nanoindentation techniques have not been standardized for use on bone tissues, making comparison of bone material properties obtained via nanoindentation across studies difficult and unreliable. This study determined a set of optimal parameter values for thermal drift correction time, dwell time, and loading rate that can be used to obtain accurate and repeatable material properties from human femoral trabecular bone through experimentation and statistical analysis. All testing was conducted using a single nanoindenter on a single trabeculae, with the assumption that material properties within the individual trabeculae were internally consistent. Parameters not of interest during this study, such as ambient …

Implementation Of An Open-Source Digital Image Correlation Software For Structural Testing, Nicole V. Buck

Master's Theses

This thesis investigates the appropriateness of a simplified, open-source digital image correlation (DIC) software for use in quasi-static, structural testing utilizing two-dimensional (2D) DIC measurements. DIC is a non-contact optical measurement technique that uses computer vision to track unique attributes on the surface of an object. For structural testing, traditional instrumentation such as displacement sensors and strain gages are impractical for full field measurements due their limited ability to capture large amounts of data. However, over the past decade, DIC has proven a successful method for full-field kinematics measurements, making it an appealing tool for collecting high densities of accurate …

Using Machine Learning To Predict Sag And Leveling Behavior Of Interior Architectural Paints, Ethan Kim

Master's Theses

In the world of interior architectural paints, rheology, or the deformation and flow of a fluid, is one of the largest economic and development hurdles for paint formulators. To achieve maximum functionality, coverage, and economy of product, the rheology of the coating must be properly optimized, balancing performance while minimizing undesirable flow defects such as paint sagging or visible brush and roller marks; these visual imperfections are associated with the sag and leveling properties of the paint. Many researchers have attempted to develop a better understanding of sag and leveling, either by drawing correlations or through mathematical derivation; however, neither …

Dairy Manure Flushwater Treatment By Algae Raceway Ponds And Aerated Biofilm Reactors, Darin Son

Master's Theses

Nitrogen removal technologies can help dairy industries meet their nutrient management needs. This thesis investigated two separate treatment technologies for total ammonia nitrogen (TAN) removal: algae raceway ponds and aerated biofilm reactors. Six 1000- liter algae raceway ponds and four 1000-liter tote tanks, each equipped with 10 sheets of nonwoven geotextile (i.e., thermally bonded or needle-punched) biofilm substrate, were used to treat the effluent from a flush dairy in central coastal California (TAN = 251 mg/L, cBOD5 = 204 mg/L). For the algae raceway ponds (TAN loading rate = 7 - 35 g/m³-day among 7-, 10- and 14-day hydraulic residence …

Transgenerational Plasticity Causes Differences In Uv-Tolerance Of Intertidal And Subtidal Populations Of The Purple Sea Urchin, Strongylocentrotus Purpuratus, Yareli Alvarez, Nikki L. Adams

Master's Theses

Planktonic larvae of marine organisms are increasingly being exposed and required to respond to a changing physical environment. Adult sea urchins occupy both intertidal and subtidal waters and broadcast spawn gametes into the water column to contend with variable physical conditions. To answer how populations of invertebrates residing at different depths adequately prepare their offspring to cope with different levels of ultraviolet radiation (UVR), we collected adult purple sea urchins, Strongylocentrotus purpuratus, from four sites (two intertidal and two subtidal (~15 m deep)) on the central coast of CA to compare UV tolerance in offspring. Our measurements of UVA …

Development Of Zeolitic Imidazolate Frameworks For Enhancing Post-Combustion Co2 Capture, Dustin Lee

Master's Theses

Post-combustion CO₂ capture is a promising approach for complementing other strategies to mitigate climate change. Liquid absorption is currently used to capture CO₂ from post-combustion flue gases. However, the high energy cost required to regenerate the liquid absorbents is a major drawback for this process. As a result, solid sorbents have been investigated extensively in recent years as alternative media to capture CO₂ from flue gases. For example, metal organic frameworks (MOFs) are nanoporous materials that have high surface areas, large pore volumes, and flexible designs. A large number of MOFs, however, suffer from 1) low CO …

Analyzing The Safety Effects Of Edge Lane Roads For All Road Users, Marcial F. Lamera

Master's Theses

This thesis acts as one of the first studies that analyzes the safety effects of Edge Lane Roads (ELR) for all road users. This is important since ELRs can be a solution to many issues, such as alleviating congestion, increasing multimodality along roadways, and reducing maintenance costs. ELRs in both North America and Australia were observed. Starting with the North American ELRs, the following study designs were employed to estimate the safety of ELRs: (a) yoked comparison where each ELR installation was matched with at least two comparable 2-lane roads to serve as comparison sites and (b) an Empirical Bayes …

Exploration And Comparison Of Image-Based Techniques For Strawberry Detection, Yongxin Liu

Master's Theses

Strawberry is an important cash crop in California, and its supply accounts for 80% of the US market [2]. However, in current practice, strawberries are picked manually, which is very labor-intensive and time-consuming. In addition, the farmers need to hire an appropriate number of laborers to harvest the berries based on the estimated volume. When overestimating the yield, it will cause a waste of human resources, while underestimating the yield will cause the loss of the strawberry harvest [3]. Therefore, accurately estimating harvest volume in the field is important to farmers. This paper focuses on an image-based solution to detect …

Sensory Stressors Impact Species Responses Across Local And Continental Scales, Ashley A. Wilson

Master's Theses

Pervasive growth in industrialization and advances in technology now exposes much of the world to anthropogenic night light and noise (ANLN), which pose a global environmental challenge in terrestrial environments. An estimated one-tenth of the planet’s land area experiences artificial light at night — and that rises to 23% if skyglow is included. Moreover, anthropogenic noise is associated with urban development and transportation networks, as the ecological impact of roads alone is estimated to affect one-fifth of the total land cover of the United States and is increasing in space and intensity. Existing research involving impacts of light or noise …

A Water Balance And Sediment Yield Analysis Model For The Lopez Lake Reservoir, Lee Joon Faraca

Master's Theses

Lopez Lake Reservoir is the primary source of potable water for the Cities of Arroyo Grande, Grover Beach, Pismo Beach, and to the Community Service Districts of Oceano and Avila Beach. In this study, a water balance and sediment yield analysis model was developed for the reservoir’s watershed. The model was used to estimate evaporation from the lake and to examine the effects of a wildfire on the reservoir. Evaporation and wildfire are dependent on variables that change on a spatial and temporal scale, making modeling challenging. The County of San Luis Obispo uses pan coefficients to estimate evapotranspiration losses …

Pressure Driven Desalination Utilizing Nanomaterials, Fangyou Xie

Master's Theses

Nanomaterials such as graphene oxide and carbon nanotubes, have demonstrated excellent properties for membrane desalination, including decrease of maintenance, increase of flux rate, simple solution casting, and impressive chemical inertness. Here, two projects are studied to investigate nanocarbon based membrane desalination. The first project is to prepare hybrid membranes with amyloid fibrils intercalated with graphene oxide sheets. The addition of protein amyloid fibrils expands the interlayer spacing between graphene oxide nanosheets and introduces additional functional groups in the diffusion pathways, resulting in increase of flux rate and rejection rate for the organic dyes. Amyloid fibrils also provide structural assistance to …

Multi-Goal Path Planning For Inventory Tracking, Christian E. Aguirre

Master's Theses

Inventory tracking plays an important role in modern warehouse management. An automated storage and retrieval system using robots can mitigate manual labor strain, reduce operational and labor costs, and improve efficiency.

Path planning is an integral component in the design and application of autonomous vehicles. In this thesis, various path planning algorithms based on RRT (rapidly exploring random trees) and RRT* (optimal rapidly exploring random trees) are studied and compared in three simulated environments with obstacles. Computer simulation results show that, the modified RRT* algorithm with node reuse achieves the best performance (i.e. the shortest path) with reasonable computational cost …

Rheological Studies Of Fully-Formulated Coatings Thickened With Heur: Effects Of Surfactants, Brandon M. Bonilla

Master's Theses

Rheology modifiers such as hydrophobically-modified ethoxylated urethane (HEUR)thickeners are included in waterborne latex coatings to optimize shear-rate dependent viscosity and other rheological properties. While these HEUR polymers are commonly used in industry, the complex chemical interactions that contribute to rheological properties are still not completely understood. Prior work in this area has focused on understanding latex-HEUR and latex-surfactant-HEUR interactions that affect rheological properties. Additionally, studies have been previously conducted to understand the relaxation mechanisms of complex interactions present in HEUR-thickened waterborne latex coatings under various dynamic conditions. The objective of this work is to extend the experimental work to fully-formulated …

Design And Synthesis Of Fluorescent Silica Nanoparticle Conjugates For Metal Ion Sensing Applications, Hank Deuermeyer

Master's Theses

A novel series of fluorescent nanoparticle conjugates were designed and synthesized for the selective turn-off sensing of low concentrations of Cu2+ ion (nM-μM) in 2:1 ethanol:10 mM HEPES (pH 7). Silica nanoparticles (~250 nm) were modified with heterobifunctional polyethylene glycol (PEG) linkers and a third generation PAMAM dendron to function as chelator for Cu2+ ions. The organic dye fluorescein isothiocyanate (FITC) was subsequently conjugated to the dendron to act as a fluorescent sensitizer for the nanoparticle that is quenched upon the binding of Cu2+. Fluorescent nanoparticle conjugates using third and fourth generation PAMAM dendrimers (SNP-G3-FITC and SNP-G4-FITC) were synthesized for …

An Investigation Of Antenna, Ligand Side-Chain, And Metal Ion Effects On The Optical And Mri Properties Of Bimodal Lanthanide (Iii) Complexes, Marisa Poveda

Master's Theses

Magnetic Resonance Imaging (MRI) is a leading anatomical imaging modality for disease diagnosis. With the aid of Gd³⁺ based contrast agents, high resolution images of biological structures can be obtained. However, there is an increased need for contrast agents that are responsive to specific analytes and chemical environments. Paramagnetic Chemical Exchange Saturation Transfer (PARACEST) agents that utilize a paramagnetic lanthanide ion chelated with a ligand have shown great promise in this area. Lanthanide ions also possess luminescence properties that do not suffer from common limitations of conventional optical imaging agents such as autofluorescence and photobleaching. The projects described in …

Solar Pv Feasibility Study On Higher Education Institutions In Connecticut, Sai Pujitha Karanam

Master's Theses

One of the most common issue in Connecticut (CT) is the high electricity rates. CT stands among the top five states for its high electric rates due to limitation in transmission facilities and storage of natural gas. Education institutions serve as good places to install photovoltaic systems as they have a large number of buildings available. Photovoltaic systems are a growing alternative energy source that reduces the electricity demand and hence higher education institutions should start implementing these technologies to reduce the burden of paying more for electricity bills.

The primary objective of the study was to analyze the economic …

Localization Of Gli1+ Expressing Cells In Adult Mouse Molars, Divya Puri

Master's Theses

Identification of the mesenchymal stem cell (MSC) population capable of giving rise to odontoblasts secreting dentin during growth (primary dentinogenesis)and repair (reparative dentinogenesis) is critical for the development of improved pulp therapy, regeneration of dentin and ultimately, the bioengineering of functional teeth. Recent lineage tracing studies have led to the identification of several new MSCs and their associated niche referred to as the neurovascular bundle, located at the apical end of the incisor. This newly identified niche contains several populations of MSCs including Gli1⁺(glioma-associated oncogene homolog 1), cells that are activated by Shh secreted by sensory nerves. Furthermore, …

High Pressure Combustor Flame And Wall Conjugate Radiative Heat Transfer, Andressa Johnson

Master's Theses

Efficient aeronautical engines operate at higher pressure ratios and temperature, creating challenges due to higher heat loads. Thermal radiation in aviation has conventionally been treated as correction factors or scaled from experimental data. The complexity of the radiative transfer equation (RTE) leads to computational costly solutions resulting in simplified treatment. The goal of this work is to extend knowledge of non-gray gas radiation modeling to gas-turbine combustor simulations under high-pressure conditions. A one-dimensional temperature solver for combustor liners with thermal barrier coating is developed first, and a non-gray wide-band spectral model for high-pressure conditions is constructed subsequently. Both retrieve spectral …

Evaluation Of Winter Weather Prediction During Extreme Snowfall Events And Analysis On Wind Gust Prediction For Non-Convective Rain And Wind Events, Michael Walters

Master's Theses

Numerical weather prediction (NWP) models are important tools used by federal agencies and the weather enterprise to inform and warn the public about extreme weather events. Snowstorm forecasts, which can be highly impactful throughout the Northeast United States, face challenges related to microphysical and initial and boundary layer processes that hinder the accuracy of forecasts. In addition, observations of mixed phase precipitation are very sparse spatially and temporally which causes an added challenge to validate predictions. This study presents an evaluation of 38 significant snowstorms and 18 rain/wind events from 2005 to 2020 using three NWP models. Each modeling system …

Electrospray Printing: An Advanced Technique For Processing Polymers Into Thin Films For Membrane Applications, Tulasi Ravindran

Master's Theses

This thesis deals with the scope and prospects of the novel technology for electrospray printing to process polymers for liquid filtration membrane applications. First, the ability to explore novel reaction media to tune polyamide properties was demonstrated. Aromatic polyamides for reverse osmosis membranes are made by interfacial polymerization. Conventionally, interfacial polymerization is an in situ polycondensation of a diamine and an acid chloride conducted on a porous support at the interface of two immiscible solvents. Using electrospray printing, different solvent media were used to print polyamides on to ultrafiltration support membranes. It was observed that polar protic solvents formed membranes …

Galilean Invariance In Large-Eddy Simulation Of Shallow Convection, Oumaima Lamaakel

Master's Theses

In large-eddy simulations (LES) a computational-domain translation velocity can be used to improve performance by allowing longer time-step intervals. The continuous equations are Galilean invariant, however, standard finite-difference-based discretizations are not discretely invariant with the error being proportional to the product of the local translation velocity and the truncation error. Even though such numerical errors are expected to be small, it is shown that in LES of buoyant convection the turbulent large-scale flow organization can modulate and amplify the error. Galilean invariance of global flow statistics is observed in well-resolved direct numerical simulations (DNS). In LES of single-phase convection under …

Applying Transit Accessibility Metrics To Locating Affordable Housing, Robert Walsh Smith

Master's Theses

The location of affordable housing in the United States is greatly influenced by how it is funded, and current funding criteria does not make wide use of comprehensive accessibility metrics. To show the benefits of using a comprehensive metric to locate affordable housing, one such metric, the TOI, was compared with more simple measures of transit access in a case study. A qualitative assessment of the comprehensive transit metric showed improvements over a simpler measure currently used by an affordable housing program. Statistical modeling was also performed to see if the TOI could better predict whether households had adequate transit …

Human Intention Inference Using Fusion Of Gaze And Motion Information, Daniel Trombetta

Master's Theses

Enabling robots with the ability to quickly and accurately determine the intention of their human counterparts is a very important problem in Human-Robot Collaboration (HRC). The focus of this work is to provide a framework wherein multiple modalities of information, available to the robot through different sensors, are fused to estimate a human's action intent. In this thesis, two human intention estimation schemes are presented. In both cases, human intention is defined as a motion profile associated with a single goal location. The first scheme presents the first human intention estimator to fuse information from pupil tracking data as well …

Alcohol-Related Consequences: Factor Structure And Associations With Trait Mindfulness And Drinking Motivations, Lauren Carney

Master's Theses

Objective. This two-study project aimed to determine if motivations to use alcohol (coping and social motivations) mediate the relationship between trait mindfulness and a variety of alcohol-related consequences and to determine if the relationship between motivations to use alcohol and alcohol-related consequences is moderated by alcohol use. Study 1 determined the factor structure of positive and negative consequences of alcohol use. In Study 2, this structure served as the outcome across eight moderated mediation models. Method. For Study 1, data were obtained from 165 undergraduate students to perform exploratory factor analysis (EFA) on alcohol-related consequences. For Study 2, …

Snap Assistance, Food Purchasing Behaviors And Dietary Patterns Among Overweight/Obese, Pregnant, Low-Income Latinas, Marta Holovatska

Master's Theses

No abstract provided.

The Role Of Beta-Hydroxybutyrate Supplementation In A Drosophila Model Of Traumatic Brain Injury, Derek Lee

Master's Theses

No abstract provided.

Cloud Cover And Pv Intermittence: Monitoring, Forecasting And Its Economical Value, Aaron Haegele

Master's Theses

The use of all-sky cameras and ancillary sensor equipment to monitor and to adjust fine resolution short range predictions of cloud cover offers an opportunity to develop efficient energy management systems. Solar photovoltaic (PV) energy is a variable renewable energy resource since solar irradiance is highly sensitive to the intermittent nature of cloud cover. Thus, tracking and characterizing clouds passing over PV areas is a critical factor when predicting the available energy of solar sources at any given time. Capital and operational costs associated with solar PV implementation are affected when inaccurate predictions are carried out. This research uses a …

Reliability Of A Low Dose Cbct Protocol In Evaluating Sinus Pathology Associated With Potential Implant Sites: An Ex-Vivo Imaging Study, Armaghan Ahmad

Master's Theses

No abstract provided.

Identification Of Residues Essential For Hsv Icp8 Mediated Annealing Of Ssdna, Jaliyah Ashante Peterson

Master's Theses

No abstract provided.

Electrostatic Denaturation Of Dna-Cisplatin Adducts, Eddie Madrigal

Master's Theses

In this thesis, electrochemical approaches are used to determine the properties of deoxyribonucleic acid (DNA) by electrostatic denaturation. The electrochemical routine involves an application of a destabilization potential, an equilibration potential, and a square wave voltammogram (SWV) to monitor the extent of melting. Our method uses a monolayer consisting of thiol modified DNA and mercaptohexanol on a gold electrode. These electrodes are then incubated in a complementary sequence tagged with methylene blue. By using our electrostatic denaturation technique, different parameters are explored, such as surface densities, surface coverages, and ionic strengths. As proof of concept, these techniques were applied toward …