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A Multi-Scale Crystal Plasticity Finite Element Modeling Framework For Predicting Strain-Rate Sensitive Deformation Of Hexagonal Metals, William G. Feather

Master's Theses and Capstones

This work presents improvements to the methods used in crystal plasticity simulations. It shows how these improvements can be used to accurately predict the deformation behavior of two magnesium alloys, WE43, and AZ31. The first improvement to the methodology is guidance on the type of finite elements to use in explicit grain crystal plasticity simulations. This study found that quadratic tetrahedral and linear hexahedral elements are the most accurate element types included in the study. The study also concluded that tetrahedral elements are more desirable due to fast mesh generation and flexibility to describe geometries of grain structures. The second …

Infiltration Analysis Of Calibrated Stormwater Models In Swmm, Anna Laura Alegria Silveira

Master's Theses and Capstones

This research project analyzes the hydrology of two Green Stormwater Infrastructure (GSI) systems located at the University of New Hampshire (UNH) campus in Durham, NH, and compares field data to modeling results of a calibrated Storm Water Management Model (SWMM) model of each system. The studied systems were a Philadelphia Tree Trench and an Infiltration Trench, located in Parking Lot A and Parking Lot E, respectively. The Stormwater Center at UNH monitored the system wells, precipitation, and collected data since system constructions, to analyze the infiltration behavior.The fundamental reason for this research is that the SWMM model only computes infiltration …

Investigation Of Stormwater Bmp Water Quality Performance Characteristics With Respect To Storm Event Variables And Influent Event Mean Concentrations, Samuel James Lanternier

Master's Theses and Capstones

Stormwater is known to be a major source of water pollution. In addition to increased flows resulting from increased impervious area in watersheds, stormwater is known to carry pollutants such a suspended solids, hydrocarbons, and nutrients into receiving water bodies. Because of this, stormwater treatment systems, referred to as ‘best management practices’ (BMPs), are utilized to dampen peak flows, reduce total runoff volume, and remove pollutants. While many studies have investigated the effectiveness of various BMPs in the removal of pollutants, fewer studies have investigated the effects of numerous storm variables on the effectiveness of treatment systems. This thesis investigates …

2020-2021 Faculty Senate Xxv - November 30, 2020 Minutes Summary, Faculty Senate

Faculty Senate Agendas & Minutes

No abstract provided.

Assessing Microbial Residues In Soil As A Potential Carbon Sink And Moderator Of Carbon Use Efficiency, Kevin M. Geyer, Jorg Schnecker, A. Stuart Grandy, Andreas Richter, Serita D. Frey

Faculty Publications

A longstanding assumption of glucose tracing experiments is that all glucose is microbially utilized during short incubations of ≤2 days to become microbial biomass or carbon dioxide. Carbon use efficiency (CUE) estimates have consequently ignored the formation of residues (non-living microbial products) although such materials could represent an important sink of glucose that is prone to stabilization as soil organic matter. We examined the dynamics of microbial residue formation from a short tracer experiment with frequent samplings over 72 h, and conducted a meta-analysis of previously published glucose tracing studies to assess the generality of these experimental results. Both our …

Faculty Senate Agenda November 16, 2020, Faculty Senate

Faculty Senate Agendas & Minutes

No abstract provided.

Finalists Announced For Annual Innovative Idea Competition, Sustainability Institute

Sustainability Institute Blog

No abstract provided.

The Transition From Stochastic To Deterministic Bacterial Community Assembly During Permafrost Thaw Succession, Stacey J. Doherty, Robyn A. Barbato, A. Stuart Grandy, W. Kelley Thomas, Sylvain Monteux, Ellen Dorrepaal, Margareta Johansson, Jessica G. Ernakovich

Faculty Publications

The Northern high latitudes are warming twice as fast as the global average, and permafrost has become vulnerable to thaw. Changes to the environment during thaw leads to shifts in microbial communities and their associated functions, such as greenhouse gas emissions. Understanding the ecological processes that structure the identity and abundance (i.e., assembly) of pre- and post-thaw communities may improve predictions of the functional outcomes of permafrost thaw. We characterized microbial community assembly during permafrost thaw using in situ observations and a laboratory incubation of soils from the Storflaket Mire in Abisko, Sweden, where permafrost thaw has occurred over the …

Two Kinds Of Polar Knowledge, Lawrence C. Hamilton

Faculty Publications

Outreach and communication with the public have substantial value in polar research, in which studies often find changes of global importance that are happening far out of sight from the majority of people living at lower latitudes. Seeking evidence on the effectiveness of outreach programs, the U.S. National Science Foundation sponsored large-scale survey assessments before and after the International Polar Year in 2007/2008. Polar-knowledge questions have subsequently been tested and refined through other nationwide and regional surveys. More than a decade of such work has established that basic but fairly specific knowledge questions, with all answer choices sounding plausible but …

Fungal Community Structure And Function Shifts With Atmospheric Nitrogen Deposition, Jessica A. M. Moore, Mark A. Anthony, Gregory J. Pec, Lidia K. Trocha, Artur Trzebny, Kevin M. Geyer, Linda T. A. Van Diepen, Serita D. Frey

Faculty Publications

Fungal decomposition of soil organic matter depends on soil nitrogen (N) availability. This ecosystem process is being jeopardized by changes in N inputs that have resulted from a tripling of atmospheric N deposition in the last century. Soil fungi are impacted by atmospheric N deposition due to higher N availability, as soils are acidified, or as micronutrients become increasingly limiting. Fungal communities that persist with chronic N deposition may be enriched with traits that enable them to tolerate environmental stress, which may trade-off with traits enabling organic matter decomposition. We hypothesized that fungal communities would respond to N deposition by …

Plant Invasion Impacts On Fungal Community Structure And Function Depend On Soil Warming And Nitrogen Enrichment, Mark A. Anthony, K. A. Stinson, Jessica A. M. Moore, Serita D. Frey

Faculty Publications

The impacts of invasive species on biodiversity may be mitigated or exacerbated by abiotic environmental changes. Invasive plants can restructure soil fungal communities with important implications for native biodiversity and nutrient cycling, yet fungal responses to invasion may depend on numerous anthropogenic stressors. In this study, we experimentally invaded a long-term soil warming and simulated nitrogen deposition experiment with the widespread invasive plant Alliaria petiolata (garlic mustard) and tested the responses of soil fungal communities to invasion, abiotic factors, and their interaction. We focused on the phytotoxic garlic mustard because it suppresses native mycorrhizae across forests of North America. We …

A Research Record, Beth Potier

UNH Today Archive

No abstract provided.

Stoichiometrically Coupled Carbon And Nitrogen Cycling In The Microbial-Mineral Carbon Stabilization Model Version 1.0 (Mimics-Cn V1.0), Emily Kyker-Snowman, William R. Wieder, Serita D. Frey, A. Stuart Grandy

Faculty Publications

Explicit consideration of microbial physiology in soil biogeochemical models that represent coupled carbon–nitrogen dynamics presents opportunities to deepen understanding of ecosystem responses to environmental change. The MIcrobial-MIneral Carbon Stabilization (MIMICS) model explicitly represents microbial physiology and physicochemical stabilization of soil carbon (C) on regional and global scales. Here we present a new version of MIMICS with coupled C and nitrogen (N) cycling through litter, microbial, and soil organic matter (SOM) pools. The model was parameterized and validated against C and N data from the Long-Term Inter-site Decomposition Experiment Team (LIDET; six litter types, 10 years of observations, and 13 sites …

Globe Student Research Symposia 2019 Evaluation Report, Eleanor M. Jaffee, Globe U.S. Coordination Office

Publications and Media

No abstract provided.

Drilling Operations For The South Pole Ice Core (Spicecore) Project, Jay A. Johnson, Tanner W. Kuhl, Grant Boeckmann, Chris Gibson, Joshua Jetson, Zachary Meulemans, Kristina Slawny, Joseph M. Souney

All Materials

Over the course of the 2014/15 and 2015/16 austral summer seasons, the South Pole Ice Core project recovered a 1751 m deep ice core at the South Pole. This core provided a high-resolution record of paleoclimate conditions in East Antarctica during the Holocene and late Pleistocene. The drilling and core processing were completed using the new US Intermediate Depth Drill system, which was designed and built by the US Ice Drilling Program at the University of Wisconsin–Madison. In this paper, we present and discuss the setup, operation, and performance of the drill system.

Staf Spotlight: At The Edge Of Hookup Culture, Lily Greenberg

UNH Today Archive

No abstract provided.

Securities Regulation And Social Media, Seth C. Oranburg

Law Faculty Scholarship

Federal securities regulation originally divided corporate finance into two neat categories, public and private. In 1933, private financing was limited to “sophisticated” investors but otherwise lightly regulated. Public financing became heavily regulated. In 1982, the SEC introduced Reg D, which introduced the concept of “general solicitation” to clarify the distinction between public and private offerings. Reg D is well understood to prohibit newspaper advertisements and permit direct solicitations to venture capital investors. This enabled great wealth consolidation in regions like Silicon Valley while effectively banning general solicitations in private offerings.

Now, social media communication challenges the definition of “general solicitation.” …

Unh: The Magazine Of The University Of New Hampshire, Fall 2020, Unh Magazine

UNH Magazine

This editon of UNH Magazine was digital only due to the COVID-19 Pandemic. This is an archived version of web content originally found at https://magazine.unh.edu/

Exploring Student Motivation In Quantitative Biology, Alexander Richard Kulacki

Master's Theses and Capstones

The field of biology is becoming increasingly reliant on quantitative tools, methods, and techniques, driving a need for incoming biologists to have robust quantitative skills. However, efforts to incorporate more quantitative skills at the undergraduate level are hampered by low student engagement with math in biology. Students’ motivation towards quantitative biology can provide insight into how best to increase their engagement and thus performance with these topics. This thesis examines students’ motivation towards math in biology through two key constructs: 1) students’ self-efficacy, through the theoretical lens of Social Cognitive Theory; and 2) students’ task-values, through the theoretical lens of …

A Biogeochemical-Economic Model For The Valuation Of Cover Crops Ecosystem Services Under Climate Change, Karen M. Moran-Rivera

Master's Theses and Capstones

Cover crop (CC) adoption is a promising conservation practice that provides multiple ecosystem services, such as reduced nitrate pollution and increased soil health. These CC ecosystem services have been demonstrated in the biogeochemistry literature. However, widespread adoption of CC in the Midwestern U.S. is still low, in part because there continues to be a debate about whether adopting CC is privately optimal for farmers and how climate change might affect the private incentives to adopt. Economic analyses of CC adoption are complicated by the difficulty to account for the economic benefits of CC ecosystem services, in a changing climate.

In …

Distributed Cooperative Control Of Multi-Agent Systems Under Detectability And Communication Constraints, Himadri Basu

Doctoral Dissertations

Cooperative control of multi-agent systems has recently gained widespread attention from the scientific communities due to numerous applications in areas such as the formation control in unmanned vehicles, cooperative attitude control of spacecrafts, clustering of micro-satellites, environmental monitoring and exploration by mobile sensor networks, etc. The primary goal of a cooperative control problem for multi-agent systems is to design a decentralized control algorithm for each agent, relying on the local coordination of their actions to exhibit a collective behavior. Common challenges encountered in the study of cooperative control problems are unavailable group-level information, and limited bandwidth of the shared communication. …

Reducing Dropout Rates Of New Hampshire High School Students By Increasing The Compelled Years Of Attendance: An Analysis Of Local Administrator Perceptions Of And Responses To State Law 193:1, Andrew K. Korman

Doctoral Dissertations

In 2007 New Hampshire passed a law, RSA 193:1, that changed the compulsory age of education for all public school students from age 16 to age 18. The purpose of this research is to explore the effect of RSA 193:1 on dropout rates in New Hampshire’s public high schools and to examine the perception of the high school principal in understanding the effect of the law and any differential effects of the law on students. Through an examination of five years of dropout data combined with a survey to current high school principals, findings indicate that there is strong support …

Experiments And Modeling Of Plastic Anisotropy And Ductile Fracture Under Multiaxial Loading, Madhav Baral

Doctoral Dissertations

The implementation of new materials for light-weighting purposes in the automotive industry has often been hindered due to the low ductility of these materials, as well as inadequate empirical knowledge about their fracture behavior and inadequate material modeling techniques. This thesis addresses these issues through extensive experimental and numerical study of plastic anisotropy and ductile fracture of several aluminum alloys and a stainless-steel. The test materials used for this study include AA365 die-casting, AA6013 and AA6111 aluminum sheets, AA6260 aluminum tube and SS304L stainless-steel microtube. The plastic anisotropy is assessed using uniaxial tension, plane-strain tension and disc compression experiments for …

Nutrient Cycling Along Microbial And Lithologic Gradients And Fostering Student Self-Confidence In Science, Kiley Remiszewski

Doctoral Dissertations

Increased understanding of the impact of biology on weathering rates and its response to environmental factors will lead to more accurate global models and enhanced management practices to optimize productive, healthy forests. Although biological contributions to weathering are established in the literature, more data to translate these observations for implementation in a predictive framework should be obtained (e.g. Taylor et al., 2012). Mycorrhizal fungi have implications for global carbon cycling and increasing carbon storage in soils (Soudzilovskaia et al., 2019) but the extent of their impact is still an area of active research with more studies of local weathering sites …

Internet-Of-Things (Iot) Security Threats: Attacks On Communication Interface, Mohammad Mezanur Monjur

Master's Theses and Capstones

Internet of Things (IoT) devices collect and process information from remote places and have significantly increased the productivity of distributed systems or individuals. Due to the limited budget on power consumption, IoT devices typically do not include security features such as advanced data encryption and device authentication. In general, the hardware components deployed in IoT devices are not from high end markets. As a result, the integrity and security assurance of most IoT devices are questionable. For example, adversary can implement a Hardware Trojan (HT) in the fabrication process for the IoT hardware devices to cause information leak or malfunctions. …

Recursive Path Following In Log Polar Space For Autonomous Leaf Contour Extraction, Anna Claire Snarski

Master's Theses and Capstones

Use of image segmentation has caused agriculture advancement in species identification, chlorophyll measurements, plant growth and disease detection. Most methods require some level of manual segmentation as autonomous image segmentation is a difficult task. Methods with the highest segmentation precision use a priori knowledge obtained from user input which is time consuming and subjective. This research focuses on providing current segmentation methods a pre-processing model that autonomously extracts an internal and external contour of the leaf. The model converts the uniform Cartesian images to non-uniformly sampled images in log polar space. A recursive path following algorithm was designed to map …

Dynamic And Structural Analyses Of A Gravity Fish Cage Employing Copper Alloy Netting, Michael James Osienski

Master's Theses and Capstones

Aquaculture, the process of growing marine plants and animals in the ocean, has been rapidly expanding due to increased seafood consumption coupled with the steady decrease of wild fish stocks. Increasing environmental concerns due to near-shore farming practices have pressured farmers to expand into more energetic open ocean sites. Environmental loading in these off-shore sites can deform common non-rigid aquaculture fish cages, reducing the cage’s net chamber volume, which can severely impacting the health of the rearing fish.

Copper alloy nets have emerged as a possible alternative to traditional polymer (nylon) twine used in the net chamber of fish cages. …

Characterization Of A Variable Diameter Bioreactor (Vdb), Zhe Su

Master's Theses and Capstones

Bioreactors for cell culture or fermentation are widely used for the production of proteins and other value-added products. Operation of bioreactors at large scale involves progressively increasing the culture volume in 4 to 10 folds increments to inoculate the culture and scale it up stepwise. To initiate the cell growth in a typical bioreactor of 20,000L, it often requires a train from benchtop scale at 1L to 10L, 100L, 1000L, 4000L and finally the 20,000L bioreactor. The transfer of cells from one bioreactor to the next one inevitably involves “lag phase” at the beginning of each culture, during which cells …

Staf Spotlight: The Secret Is In Making Connections, Lily Greenberg

UNH Today Archive

No abstract provided.

New Paul College Associate Dean For Undergraduate Education Named, Sharon Keeler

UNH Today Archive

No abstract provided.