Digital Commons Network^™

Characterization Of Sediment-Flow Interactions In Tidally Driven Salt Marsh Environments, Elijah Rousseau

Master's Theses and Capstones

Salt marshes are effective sediment traps and under static sea levels are known to increase in elevation over time. However, current sedimentation rates are insufficiently high to keep up with the estimated sea level rise. Strategies such as the mud motor, which proposes the injection of dredged sediment into incoming flood tides, require a deeper understanding of how tidal flows evolve in complex estuarine systems and how suspended sediment is dispersed and deposited in vegetated environments. Two field deployments occurred in the summer of 2023 to study the mechanisms of sediment transport and accretion along a horizontal marsh transect in …

The Nature Of Students' Justifications In Geometry: The Impact Of Using Dynamic Geometry Software, Anek Janjaroon

Doctoral Dissertations

Mathematical justification is a process that reflects how students demonstrate and accept the truth of mathematical statements. The purpose of this study was to investigate the nature of students’ justifications when allowed to use dynamic geometry software in the justification process. The justifications of 18 preservice teachers in response to two geometric conjectures were analyzed to identify characteristics of justifications based on Harel and Sowder’s (1998) framework of proof schemes. The results inform us of the impact of the dynamic software in students’ justifications and the overall nature of students’ work when they use the software to learn geometric ideas. …

Global Imaging Of The Magnetoshpere: An In-Depth Analysis Of The Magnetosphere-Ionosphere Coupling, Mayowa Adewuyi

Doctoral Dissertations

Magnetosphere – Ionosphere (MI) coupling plays an important role in Earth’s overall space environment. MI coupling influences ion dynamics in the plasma sheet, the evolution of ring current ions, and field aligned currents during storm time events. The coupling of these two regions makes it important to understand both as a whole, rather than individually. Understanding the importance of the magnetosphere-Ionospheric system and how the coupling affects earth’s space environment is made difficult due to the reliance on localized in-situ measurements and the spacecraft being at the right location at the right time.

The Two Wide-Angle Imaging Neutral-Atom Spectrometers (TWINS), …

12-Year Full Solar Cycle Maps Of Interstellar Neutral Atoms By Ibex-Lo And The Observation Of Elastic Scattering Of Primary Helium By Solar Wind Particles, Hafijul Islam

Doctoral Dissertations

The Interstellar Boundary Explorer (IBEX) mission is playing a pivotal role in advancing our understanding of the interaction between the very local interstellar medium (VLISM) and the heliosphere. By sampling interstellar neutral (ISN) atoms and energetic neutral atoms (ENA), IBEX has provided over 15 years of continuous data over a range of energy from 15 eV to 6 keV, offering an invaluable opportunity to study these interactions across various phases of solar activity. The IBEX-Lo instrument, which detects lower-energy ISNs, has been particularly useful in exploring the properties of hydrogen and helium in the interstellar medium, as well as their …

The Genomic Basis Of Adaptation In Salt-Marsh-Breeding Sparrows, Jonathan David Clark

Doctoral Dissertations

Salt marshes are an ecotone between terrestrial and marine environments characterized byshort, graminoid vegetation and periodic tidal inundation with saline water. Despite the generally inhospitable conditions salt marshes present for terrestrial vertebrate life—principally, exposure to heat, salinity, and flooding—several terrestrial vertebrate species have adapted to, or are capable of inhabiting salt marshes. Notably, species of passerine birds that have adapted to salt marshes have repeatedly evolved a similar suite of adaptations, which has been named the “saltmarsh syndrome,” including larger bills, darker plumage, and an increased tolerance of salt.

The myriad species of New World sparrows (Passerellidae) that breed in …

A Physics-Based Material Model Incorporating Strain Gradient Plasticity Formulations In A Mean-Field Framework To Predict Spatial Fluctuation Of Material Properties, Zhangxi Feng

Doctoral Dissertations

With the market expansions and increasing number of scientific explorations, the demands for manufacturing metallic parts to satisfy specific requirements continue to increase. A slight improvement in the manufacturing process can result in great cost savings in time and energy. The research and development time to identify these areas of improvements can be greatly reduced using numerical models. One such model is the mean-field elastoplastic self-consistent (EPSC) framework studied extensively and advanced in this dissertation. In the past two decades, many material behavior formulations were implemented in EPSC, and the model has shown versatility and accuracy in predicting a wide …

“Why You Understand The Why”: A Qualitative Characterization Of The Metacognitive Competence Of Introductory Stem Peer Coaches, Jonathan Kustina

Doctoral Dissertations

The processes of metacognition are vital for students’ development of critical thinking skills and productive learning mindsets, yet many students never receive the direct instruction that would allow them to formally develop their metacognition. As instructors are typically not providing this instruction, there may be an alternate source to facilitate the learning of metacognition to students. This research study will investigate the viability of having peer coaches, undergraduate peer educators who help facilitate learning and problem solving in introductory STEM courses, facilitate metacognition to their students. Specifically, this research study aims to understand and characterize the metacognitive competence of the …

Engineer-Friendly Synergetic Methodology For Surrogate Modeling Of Complex Connections By Modal-Based Low-Fidelity Finite Element Model Updating Approach, Milad Mehrkash

Doctoral Dissertations

Finite element models are widely used to simulate the behavior of structures. They can also be utilized for structural condition assessment and health monitoring. However, due to software limitations, simplifying assumptions, and lack of knowledge about the system properties, the predictions of the numerical models may deviate from laboratory or field measurements of the actual structure. This issue may be further exacerbated by the simplifications applied in modeling complex connections, which is a common practice in numerical modeling to save time and effort. While finite element model updating improves the accuracy of numerical models, physics-based surrogate modeling of connections balances …

Artificial Intelligence Driven Magnetic Materials Discovery: From Data Extraction To Property Prediction, Yibo Zhang

Doctoral Dissertations

This dissertation presents an integrated artificial intelligence framework aimed at accelerating magnetic materials discovery by addressing key challenges in materials science: improving experimental characterization techniques, efficiently extracting structured data from scientific literature, developing comprehensive materials databases, and creating reliable predictive models.

We first develop a UNet-enhanced vector field electron tomography (VFET) approach for three-dimensional magnetic structure reconstruction. This method addresses the missing wedge problem in experimental data collection while maintaining computational efficiency, providing reliable experimental data crucial for materials research.

We introduce GPTArticleExtractor, a novel workflow leveraging large language models to automatically extract key information from scientific literature. Applied to …

Functional Characterization Of Copper Tolerance In The Atypical Microsymbiont Pseudofrankia Inefficax, Megan Paige Garcia

Doctoral Dissertations

Bacterial species in the family Frankiaceae are soil-dwelling microsymbionts that form a mutualistic symbiosis, termed the actinorhizal symbiosis, with over 220 species of woody dicots. In this relationship, frankia fix atmospheric nitrogen to ammonia, a form usable by plants, while the bacteria benefit from the carbon sources exuded by their actinorhizal hosts. Since nitrogen is typically a limiting nutrient for growth in degraded and contaminated soils, actinorhizal plants establish at these sites as pioneer plant species, initiating a path for phytoremediation. Likely due to their association with plant hosts in contaminated soils, most frankia strains have evolved above average tolerances …

Improving Understanding Of Fluvial Reach-Scale Solute Transport And Uptake Using A Particle Tracking Model And Random Forest Machine Learning Model, Jiaying Liu

Doctoral Dissertations

In addition to transporting flowing water, river systems carry dissolved nutrients and pollutants, which can experience chemical reactions, biological uptake, or retention in surface or hyporheic zones. This dissertation enhances our understanding of solute transport and uptake in river reaches through three main components. The first component involves the development of a novel curve-fitting model designed to capture the characteristics of pulse-release breakthrough curves (BTCs) from tracer studies with conservative solutes. The model, which was found to be applicable to a wide range of field studies, enables the rapid comparison of transport parameters among diverse field studies obtained under a …

Deformation-Induced Bonding Of Glassy Polymeric Films And The Diluent Effect, Ajay Vallabh

Doctoral Dissertations

Bonding between two polymer films can be achieved through various heat- or chemical-based methods. Recently, our group has discovered the novel phenomenon of deformation-induced bonding (DIB) for solid-state glassy polymers in time on the scale of a fraction of a second at ambient temperatures substantially below the bulk glass transition temperatures (T_g). DIB is achieved by bulk plastic compression, which triggers the molecular mobility of polymer chains to cause interpenetration across the interface even in a glassy regime.

First, we performed a series of experiments to evaluate solid-state, deformation-induced bonding in organic polymer blends composed of films of hydroxypropyl methylcellulose …

Carroll County Advisory Council Minutes 2020, Mikayla Cerney

UNH Cooperative Extension

No abstract provided.

Characterizing The Usda-Npgs Germplasm Collection Of Tartary Buckwheat (Fagopyrum Tataricum), Noah Joseph Abasciano

Master's Theses and Capstones

AbstractTartary buckwheat (Fagopyrum tataricum) is a promising underutilized crop in the context of New England’s rapidly changing environment (USDA NH State Profile, 2022). Despite substantive prior work on the genetics and nutrition of Tartary buckwheat (Zhang et al., 2017b), many practical questions pertaining to its potential cultivation in New England remain unanswered. This thesis presents the first systematic genotypic and phenotypic screening of the USDA National Plant Germplasm System's (NPGS) Tartary buckwheat germplasm collection in an effort to lay the foundations for future crop improvement efforts. The genotypic assessment of the NPGS Tartary buckwheat germplasm was completed by first bottlenecking …

Characterizing Tropical Forest Structure Using Semivariance And Crown Delineation, Brittani Joy Evon Chapman

Master's Theses and Capstones

The study of terrestrial carbon stocks is essential to understand global carbon cycles and the magnitude of anthropogenic carbon emissions. Forests are significant terrestrial carbon stores, with the above ground biomass of the Brazilian rainforest alone conservatively estimated to contain ten percent of the terrestrial carbon stock (Asner et al., 2001; Drake et al., 2002; Keller et al., 2004; Lloyd et al., 2007; Truehaft et al., 2014; Cushman et al., 2021). The Amazon Basin primarily consists of closed-canopy tropical forest, covering 5.8 x 106 km2 interspersed with substantial portions of cerrado surrounding the Amazon River and its tributaries in the …

Feasibility Analysis On Bluff Body Wake Detection Via Cost-Effective Sensors And State And Parameter Estimation Techniques, Patrick Michael Close

Master's Theses and Capstones

This thesis investigates the feasibility of using Uncrewed Aerial Vehicles (UAVs) and existing state estimation techniques for detecting aerodynamic wakes around bluff bodies. Aerodynamic wakes are complex, turbulent flow regions created by obstacles. Accurately measuring these wakes is crucial for applications such as optimizing wind energy production, improving aircraft safety, and enhancing atmospheric research. Traditional measurement methods, such as ground-based sensors or piloted aircraft, have significant limitations, including restricted spatial coverage and high operational costs. UAVs, with their versatility and cost-effectiveness, present an alternative approach to measuring wakes in challenging environments.

This research focuses on three state estimation techniques: the …

Behavioral And Physiological Effects Of Ocean Acidification On Juvenile American Lobsters (Homarus Americanus), Todd Edward Stelling

Master's Theses and Capstones

Increased absorption of anthropogenic carbon dioxide (CO2) into the world’s oceans has resulted in ocean acidification (OA). Acidification induces physiological and behavioral responses from marine invertebrates that vary by taxa. Resilience to OA has been noted in crustaceans, though negative impacts are still reported. It has been shown that the American lobster (Homarus americanus) can be physiologically impacted by acidified conditions. We explored the effects of acidification on the hemolymph chemistry and the foraging behavior of juvenile American lobsters (carapace length, CL, 29 - 52 mm, 42 +/- 1.3 mm). We exposed 28 juvenile lobsters to individual pH values ranging …

Proceeding Toward The Maximum Of Solar Cycle 25 With A Radiation Environment Similar To The Previous Cycle, Fatemeh Rahmanifard, Morgan L. Macleod, Wouter C. De Wet, Andrew P. Jordan, Jody K. Wilson, Harlan E. Spence, Nathan A. Schwadron

Faculty Publications

The Sun exhibited lower-than-average activity levels, including a weak maximum and a prolonged minimum in the solar cycle (SC) 24. Thiswas following a 60-year trend of weakening solar activity, leading to speculations that we could be moving into another secular minimum scenario like the Dalton or the Gleissberg periods. During such periods, the fluxes of galactic cosmic rays (GCRs) increase significantly, introducing radiation hazards for long-term crewed space explorations. In our previous work, we predicted the level of solar activity, and thus, the radiation environment for SC25 will be similar to SC24. In this paper, we show that, to date, …

Plasticity Characterization Of Sheet Metals Using Torsional In-Plane Shear Testing, Matthew Eaton

Master's Theses and Capstones

In the field of sheet metal forming, it is important to accurately model the plastic stress-strain behavior of materials for use in simulations. Various tests are performed to characterize the plastic behavior, such as plastic anisotropy and strain hardening, which is used to identify material parameters of constitutive models. Shear testing in particular is an area of increasing interest in metal forming applications due to significantly larger strain level compared to uniaxial tension. This thesis aims to design a torsional in-plane shear testing fixture, to characterize the strain hardening and plastic anisotropy in shear for DDQ and DP980 steel sheets, …

Incremental Nicotinic Acid Supplementation To Preweaned Dairy Calves: Effects On Growth, Blood Metabolites, Purine Derivatives And Indirect Rumen Development, Tamanna Islam

Master's Theses and Capstones

The purpose of this experiment was to investigate the dose response of nicotinic acid (NA) on body growth, blood glucose and β-hydroxybutyrate (BHBA) concentrations, and urinary purine derivatives (PD) excretion in preweaned dairy calves. A total of 40 (22 male and 18 female) Holstein dairy calves averaging initial body weight 42.5 ± 5.60 kg (mean ± SD) were blocked by birth and randomly assigned to 1 of 4 levels of NA: (1) 0 g/d (CON), (2) 2 g/d (2NA), (3) 4 g/d (4NA), and (4) 6 g/d (6NA). Following parturition, calves were separated immediately from their dams before suckling and …

2023 Carroll County Advisory Council Minutes And Agendas, Mikayla Cerney

UNH Cooperative Extension

No abstract provided.

Resilience And Positive Feedbacks: Water Quality Management And Eelgrass Health In Great Bay Estuary, Nh/Me Technical Report, Anna Mikulis, Chris Peter, Cory Riley, David M. Burdick, Kalle Matso, Kelle Loughlin, Lynn Vaccaro, Miguel Leon, Thomas Gregory, Tom Lippmann, William H. Mcdowell

PREP Reports & Publications

This comprehensive technical report outlines the project’s motivations, context, methods, results, and discussion of results in the context of local management concerns. It provides evidence-based recommendations for decision makers in the region looking to better understand water quality, light, and eelgrass relationships.

Quality Assurance Report For Year 2023 Estuarine Water Quality Datasonde Monitoring, Lara M. Martin

PREP Reports & Publications

No abstract provided.

Implications Of Energetic Neutral Atoms Observed With Ibex-Lo For The Pressure Balance In The Heliosphere, André Galli, Peter Wurz, Nathan A. Schwadron, Eberhard Möbius, Stephen A. Fuselier, Justyna M. Sokół, Maciej Bzowski, Paweł Swaczyna, Kostas Dialynas, David J. Mccomas

Faculty Publications

Energetic Neutral Atoms (ENAs) from the heliosphere are a unique means to remotely image the boundary regions of our heliosphere. NASA's Interstellar Boundary Explorer (IBEX) has been very successful in measuring these ENAs since 2008 at energies from tens of eV to 6 keV.The ENA low energy range from tens of eV to solar wind energy (roughly 1 keV) has been sampled throughout an entire solar cycle with the IBEX-Lo ENA imager. This enables us to study the physical implications for the structure of the heliosphere and for the parent proton populations in the heliosheath and other plasma regions that …

The Climate Impact Of Tropical Peatland Degradation, René Dommain, Steve Frolking, Aurich Jeltsch-Thömmes, Fortunat Joos, John Couwenberg, Paul Glaser, Alexander Cobb, Charles Harvey

Faculty Publications

Southeast Asia is a global hotspot of peatland degradation and related greenhouse gas emissions. Anthropogenic impacts, mainly associated with agricultural conversion, shift Southeast Asian peatlands from carbon sinks to significant carbon sources. Here we first describe the impacts of anthropogenic drainage on landscape-scale carbon dynamics of individual peatlands and then use an impulse‐response model of radiative forcing to quantify the climate impacts of peat-carbon losses. Whereas water-table elevation (i.e. drainage depth) determines the magnitude of CO2 emissions at the site-scale, the geometric arrangement of artificial drainage networks determines carbon losses on the landscape-scale. Among all peatland greenhouse gas fluxes, the …

The Climate Impact Of Tropical Peatland Degradation, René Dommain, Steve Frolking, Aurich Jeltsch-Thömmes, Fortunat Joos, John Couwenberg, Paul Glaser, Alexander Cobb, Charles Harvey

Faculty Publications

Southeast Asia is a global hotspot of peatland degradation and related greenhouse gas emissions. Anthropogenic impacts, mainly associated with agricultural conversion, shift Southeast Asian peatlands from carbon sinks to significant carbon sources. Here we first describe the impacts of anthropogenic drainage on landscape-scale carbon dynamics of individual peatlands and then use an impulse‐response model of radiative forcing to quantify the climate impacts of peat-carbon losses. Whereas water-table elevation (i.e. drainage depth) determines the magnitude of CO2 emissions at the site-scale, the geometric arrangement of artificial drainage networks determines carbon losses on the landscape-scale. Among all peatland greenhouse gas fluxes, the …

Monte Carlo Error Analysis Of Lightning Interferometry With Lofar, Paulina Turekova, Brian Hare, Olaf Scholten, Steven Cummer, Joseph Dwyer, Ningyu Liu, Chris Sterpka, Sander Ter Veen

Faculty Publications

The LOFAR radio telescope works on a principle of radio interferometric imaging. It coherently sums the signal of hundreds of antennas in northern Netherlands, covering the 30-80 MHz window of the very high frequency (VHF) band of 30-300 MHz. We are using the TRI-D algorithm to extract 3-D polarization data of a lightning flash observed by LOFAR. TRI-D functions by coherently summing recorded voltages, accounting for the antenna function, polarization, and geometric time delay for each voxel. The result is split into time slices. A coherent intensity is calculated for each time slice, and the maximum of this value is …

Very Minor Ions In The Magnetosphere: A Hub Of The Mesospheric, Ionospheric, Magnetospheric, Solar Wind, Lunar, And Meteoroid Sciences., Masatoshi Yamauchi, Iannis Dandouras, Peter Würz, Daniel Kastinen, John Plane, Leonard Schulz, Andrew Yau, Lynn M. Kistler, Steve Christon, Stein Haaland, Yoshifumi Saito, Satonori Nozawa, Ingrid Mann, Shigeto Watanabe, Tinna Gunnarsdottir

Faculty Publications

This is the summary of findings by ISSI topical team on the molecular and metallic ions in the magnetosphere.Heavy molecular and metallic ions with mass ≥ 27 (Al+, N2+, NO+, O2++, Fe+, Cu+, Ti+, etc) in the magnetosphere provide independent information on the ion sources and entry route to the magnetosphere from traditional four components (H+, He++, He+, O+). There are four ultimate sources of these heavy molecular and metallic ions: the solar wind (high charge-state metallic ions), the ionosphere (mainly molecular ions), the atmospheric metal layers (low charge-state metallic ions and metal-rich molecular ions that ultimately originating from ablation …

Inter-Calibration Of Solar Orbiter's Heavy Ion Sensor And Suprathermal Ion Spectrograph, Benjamin Alterman, Robert Allen, Ryan Dewey, Stefano Livi, Jim Raines, Susan Lepri, Sarah Spitzer, Chris Bert, Christopher Owen, George Ho, Antoinette Galvin, Lynn M. Kistler, Frederic Allegrini, Keiichi Ogasawara, Peter Wurz, Mark Philips, Raffaella D'Amicis, Glen Mason, Robert F. Wimmer-Schweingruber, Javier Rodriquez-Pacheco

Faculty Publications

The distribution of charged particles in the heliosphere covers more than 16 orders of magnitude in particle flux and more than 6 orders of magnitude in energy. While the majority of these particles are ionized hydrogen (protons) and fully ionized helium (alpha particles), heavier ions are also present. Because of the large parameter space that must be covered, different instruments are required and these instruments must be optimized to specific energy and particle flux ranges. They must also be designed to target specific ion species. To properly characterize the means by which different energy ranges are populated, the observations from …

Monte Carlo Error Analysis Of Lightning Interferometry With Lofar, Paulina Turekova, Brian Hare, Olaf Scholten, Steven Cummer, Joseph Dwyer, Ningyu Liu, Chris Sterpka, Sander Ter Veen

Faculty Publications

The LOFAR radio telescope works on a principle of radio interferometric imaging. It coherently sums the signal of hundreds of antennas in northern Netherlands, covering the 30-80 MHz window of the very high frequency (VHF) band of 30-300 MHz. We are using the TRI-D algorithm to extract 3-D polarization data of a lightning flash observed by LOFAR. TRI-D functions by coherently summing recorded voltages, accounting for the antenna function, polarization, and geometric time delay for each voxel. The result is split into time slices. A coherent intensity is calculated for each time slice, and the maximum of this value is …