Physical Sciences and Mathematics Commons^™

Absolute Frequency Measurement Of The 2p2(3P)3s 2P–2p2(3P)3p 2DO Transitions In Neutral 14N, K. J. Ahrendsen, C. Maruko, K. R. Albert-Aranovich, Q. Berfield-Brewer, A. Esseln, L. Guo, A. E. Ishimwe, Y. Kuzniar, A. E. Mckenna, K. J.Soto Villarreal, A. Uprety, L. Vieira Da Silva, K. F. Vogt, W. D. Williams

Physics: Faculty Publications

We report absolute frequency measurements on the three excited-state transitions connecting the 2⁢��2⁡(3⁢��)⁢3⁢��2⁢��1/2,3/2 and 2⁢��2⁡(3⁢��)⁢3⁢��⁡2⁢��∘3/2,5/2 states in neutral 14N using saturated absorption spectroscopy in a glass cell filled with a mixture of nitrogen and argon gas and driven with a radio-frequency electric field. The absolute transition frequencies are found to be 319 288 834(150), 319 085 445(125), and 316 795 808(140) MHz for the 1/2–3/2, 3/2–5/2, and 3/2–3/2 transitions, respectively. This work represents the saturated absorption measurements for these transitions. These results are approximately a factor of 5 improvement over previous results, despite being conservative estimates. We found that the …

Belowground Growth Strategies Of Native And Invasive Rhizomatous Perennial Grasses In Response To Precipitation Variability, Clipping, And Competition, Surendra Bam, Jacqueline P. Ott, Jack Butler, Lan Xu

Natural Resource Management Faculty Publications

Invasive clonal species may exhibit different growth strategies than their native clonal competitors. In this study, we examined the spatial distribution of tiller outgrowth and the bud bank by comparing the investment in phalanx versus guerilla growth of a native and invasive perennial grass in North America. We also examined the efect of altered precipitation frequency, clipping, and competition on their clonal growth strategies. Investment in phalanx and guerilla growth was assessed by examining live propagule and tiller production from the plant crown versus its rhizomes. Although invasive Bromus inermis and native Pascopyrum smithii exhibited similar clonal growth strategies as …

Economic And Environmental Performance Of Integrated Crop-Livestock Systems: Resilience To Uncertainties And An Opportunity For Sustainable Intensification, Maroua Afi

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Integrated crop-livestock systems are promoted as an alternative for sustainable intensification of food production. They have the potential to offer enhanced input efficiency and maintain a diversified livelihood which plays an important role in building resilience of agricultural systems. This work aims to evaluate the technical efficiency of “Integrated Crop-Livestock Systems” (ICLS), “Specialized Livestock Systems” (SLS) and “Specialized Cropping Systems” (SCS) and to identify the determinants behind inefficiencies in these systems. It also aims to assess the resilience against climate variability and market fluctuations. The first chapter provides a comparative analysis and an overview of technical efficiency assessment of farming …

Flujos De Servicios Ecosistémicos En Un Área Marina Protegida Del Atlántico Sur: Perspectivas Desde El Análisis De La Teoría De Redes, Mitch Porter

Independent Study Project (ISP) Collection

En cuestiones de gestión de áreas protegidas, los servicios ecosistémicos se tienen cada vez más en cuenta junto con la conservación de la biodiversidad. Sin embargo, las decisiones que se toman sobre la conservación de los servicios ecosistémicos no suelen incluir los posibles efectos en cascada de la pérdida de biodiversidad sobre la provisión de servicios. Los conocimientos de la teoría de redes y los estudios de robustez pueden proporcionar una metodología para evaluar la vulnerabilidad de estos servicios frente la estructura trófica de los ecosistemas que los proveen. A través de una serie de simulaciones de extinción para la …

On The Rocks, Below The Rocks: A Study Of Intertidal Life In The Low, Middle And High Zones Of The Puerto Cabuyal – Punta San Clemente Marine Reserve During An El Niño Event, Juliana M. Ferrer

Independent Study Project (ISP) Collection

The rocky intertidal zone is one of the most difficult environments for organisms to survive in due to its harsh biotic and abiotic conditions. As such, it is also one of the best indicators of climate change and an important barrier to beach erosion. This study looked at the rocky intertidal zone of the Puerto Cabuyal-Punta San Clemente Marine Reserve in the Manabí province of Ecuador, with a focus on observing and identifying the organisms found in the area. Data was collected along 30 m transects at varying elevations along the shore using quadrants of two sizes: 50x50 cm for …

Soil Succession: Short And Long-Term Impacts Of Grazing On Soil Properties In A Tropical Montane Cloud Forest, June Curtis

Independent Study Project (ISP) Collection

Cattle ranching is the leading cause of deforestation in South America, causing long-lasting alterations to the continent's landscape and ecology. Tropical montane cloud forests (TMCFs) are a rare ecosystem particularly vulnerable to the effects of land conversion to pasture, a process which has implications ranging from biodiversity loss to soil degradation. Grazing is known to significantly alter soils' physical structure through processes of compaction and erosion as well as significant additions of organic matter. Silvopasture, or the integration of pasture and forest, has emerged as an alternative to traditional grazing practices with the hope of mitigating environmental and soil degradation. …

A Case Study Of Sustainable Development At The Penonomé Wind Farms, A Cdm Registered Project In Coclé, John Matuszewski

Independent Study Project (ISP) Collection

The Penonomé wind projects fit into a long history of previous internationally financed development projects in Panama, including those from the Clean Development Mechanism. A moderate level of research has been conducted on other Clean Development Mechanism projects, but despite contributing to 5% of Panama’s energy needs and constituting the largest wind park in Central America, the Penonomé wind farms remain little researched. Semi-structured interviews were conducted with relevant people associated with the project or with relevant information to gain more information about the case study. Using the information processed from these reviews and information from publicly available resources, the …

Reef Fish Wariness Behavior: Fish Flight Initiation Distance Mediated By Territoriality And Body Size In Three Reef Sites Off The Western Coast Of Isla Colón, Bocas Del Toro, Panamá, Alina G. Irvine

Independent Study Project (ISP) Collection

Coral reefs are highly productive and diverse underwater ecosystems, providing a variety of environmental services including sand generation, nutrient processing, fish supply, and tourism. However, coral reefs have been increasingly impacted by natural and anthropogenic disturbances, which has negatively affected fish security within their environment. A significant observation is the reduction in evasive behaviors among reef fish in marine reserves compared to those exposed to anthropogenic threats. The present research aims to investigate the factors mediating fish wariness behavior through an exploration of the roles of territoriality and body size on fish flight initiation distance (FID). FID is the distance …

Intelligence Versus Inferno: How Artificial Intelligence Can Be Used To Monitor And Manage Wildfires In Europe, Maxwell Feldman

Independent Study Project (ISP) Collection

Escalating wildfire occurrences in Europe, particularly in the southern Mediterranean region, are presenting significant challenges to socioeconomic, environmental, and ecosystem services. The increasing frequency and severity of these wildfires are straining resources and emphasizing the need for a better understanding of the relationship between suppression capacity and fire behavior in wildfire management. The following research addresses the urgent need for more proactive, knowledge-based, and technologically driven fire management strategies, throughout all four stages of wildfire response – fuel and land management, fire preparedness, fire suppression, and post-fire management. Artificial Intelligence (AI) is becoming increasingly significant in climate change adaptation, especially …

Environmental Loss, Displacement, And Anxiety In Portugal: Analyzing News Articles To Differentiate Manifestations Of Environmental Distress, Robin Greene

Independent Study Project (ISP) Collection

Expressions of environmental distress can take different forms, with different symptoms, causes, and treatments. Existing literature generally identifies three primary categories of environmental distress responses: environmental grief, solastalgia, and eco-anxiety. This paper explores these distinctions and identifies words typically associated with each category in Portuguese news articles using Latent Dirichlet Allocation (LDA). LDA is a Natural Language Processing (NLP) technique that groups words into topics and identifies connections between those words based on how often those words appear together in sequences. This paper uses a modified LDA algorithm called GuidedLDA to identify additional keywords within topics defined by a list …

“Without Water, Nothing”: Examining The Water Saving Practices Of Women In Amman Under Periodic Water Supply, Rory Dixon

Independent Study Project (ISP) Collection

Jordan is among the most water-scarce countries in the world. Consequently, water is only pumped to households once a week and households store water in tanks to last them until the next water day. Women conducting housework do so under conditions of environmental stress that this research calls resource-scarce domestic labor. In this study, I apply an eco-feminist lens to examine the water-saving practices women employ to manage and conserve domestic water supplies. I explore the larger causes of these behaviors including climate change, government management, and regional politics. Resource-scarce domestic labor is not a practice unique to Jordan and …

Surveillance Systems In Western Kenya: Methods, Perceptions, And Effectiveness, Marissa Duffy

Independent Study Project (ISP) Collection

Surveillance is an important tool in monitoring and evaluating infectious disease patterns and trends. Surveillance is vital because it aids public health officials and medical professionals in creating better prevention methods and efficiently managing outbreaks. Kenya is home to many noncommunicable diseases making it an important location to conduct disease surveillance. Within Kenya, each county has its own surveillance unit which tracks and controls outbreaks. In addition, government run surveillance systems were established to determine disease burden, incidence, and patterns in specific at-risk communities around Kenya. One of these major surveillance systems is Population-Based Infectious Disease Surveillance (PBIDS) which has …

Analyzing Human - Nonhuman Primate Conflict Mitigation Techniques In Mto Wa Mbu, Northern Tanzania, Lily Adams

Independent Study Project (ISP) Collection

Human – non-human primate conflict is particularly crucial due to primates’ high capacity to live among human populations. The study to analyze Human - Nonhuman Primate Conflict Mitigation Techniques, was carried in November 2023 at Mto wa Mbu, Northern Tanzania. To analyze techniques currently being used to mitigate human – non-human primate conflict, this study collected data through semi-structured interviews. Over 87% (n=35) of respondents used multiple mitigation techniques simultaneously. 80% of respondents (n=32) reported using projectiles to ward off foraging primates, 75% of respondents (n=30) reported using loud noises (made either by the voice/body or by manipulating noisemakers), 67.5% …

Representations And Realities: Misali Island's Biodiversity In Hybrid Narratives, Justin Ross Whitney

Independent Study Project (ISP) Collection

Marine Protected Areas (MPAs) are complex organisms that ebb and flow between strict and unyielding conservation doctrines often at the cost of community engagement. Misali Island is different. Conceived and advocated for by community members, this organism has navigated a tumultuous tenure of environmental degradation, periods of high and low funding, and a looming tourism presence. On top of these challenges has been a growing fishing community attempting to share in the bounty of this shockingly biodiverse setting. This study sorts through the grey space of Misali Island by applying a hybrid narrative that interfaces the marine context of the …

Always Sunny In Zanzibar: Exploring Solar Power On The Island, Quinn Brannan

Independent Study Project (ISP) Collection

As Zanzibar continues along its developmental path, the island’s energy infrastructure takes on a central role in future plans for growth. Critically, as the population grows and tourist presence is predicted to increase, the island is presented with the combined problem of supplying a greater volume of energy, while also providing a more reliable source to its existing populace. In this study, I will examine existing solar energy systems for capacity, accessibility, and reliability, as well as evaluate their efficacy in providing a functional source of power, both now and in the future. I conduct interviews with assorted stakeholders in …

Climate Change, Malnutrition, And Hiv: The Impact Of Food Insecurity On Hiv Response In Sub-Saharan Africa, Olivia Walshak

Independent Study Project (ISP) Collection

Climate change is a key driver of an unprecedented global food crisis, exacerbated by rising temperatures and the vulnerability of crop yields. Sub-Saharan Africa is particularly susceptible, and case studies demonstrate the fragility of food systems in the region, leading to severe food insecurity and famine in the face of climate shocks.

There are a variety of health implications, particularly the syndemic relationship between malnutrition and HIV. HIV interacts bidirectionally with malnutrition, creating a vicious cycle of poor clinical outcomes. Expanding access to antiretroviral therapy in Sub-Saharan Africa is hindered by rampant food insecurity, including inadequate food intake, reduced dietary …

A Reflection Of Change: Evolutions In International Water Law Principles Through The Lens Of Euphrates-Tigris Dispute, Maeve Sullivan

Independent Study Project (ISP) Collection

As climate change intensifies, water scarcity will increase. Coupled with a growing global population, water security is a major modern challenge. To bring stability to international watercourses, states must establish effective sharing agreements. On this matter, international water law can help. International water law captures some of the major principles and considerations that states must account for while considering issues related to water security. This paper uses primary interviews and secondary sources to identify some of the major characteristics, features, and developments in international law to develop a conceptual framework for the topic. It then moves into a case study …

Lha, Lu, And Shipda: Religious Landscape In A Conservation Area, Luke Stumpfl

Independent Study Project (ISP) Collection

Living in a political, cultural, and geographic border region between Nepal and Tibet (People’s Republic of China), the families of Tsum Valley face many demands from their sociopolitical, religious, and economic climate. Practicing Tibetan Buddhism, the people uphold a set of rules implemented by the community with leadership from Serap Dorje Drukpa Rinpoche over 100 years ago that prohibits the intentional murder of all animals. Hailed by leaders and scholars as a haven of biodiversity conservation due to this customary-turned- municipal law, Tsum Valley also exists within Manaslu Conservation Area governed by an entity of the federal government of Nepal …

Analyzing Stress Levels Of Volunteers Hand-Rearing Juvenile Spectacled Flying Foxes (Pteropus Conspicillatus) At The Tolga Bat Hospital, North Queensland, Australia, Olivia Knight

Independent Study Project (ISP) Collection

This study, conducted at the Tolga Bat Hospital in North Queensland, Australia, focuses on analyzing the stress levels of volunteers hand-rearing juvenile spectacled flying foxes (Pteropus conspicillatus). Given the endangered status of this species and the intensive care required for their rehabilitation, the research aimed to understand the physical, emotional, and mental well-being of the volunteers engaged in this demanding conservation work. The study was conducted over a five-day period during the peak pupping season in November 2023, utilizing self-administered questionnaires to assess the well-being and stress levels of volunteers both before and after their nursing sessions. The participants, primarily …

Creating A Framework For An Effective Koala Recovery Center: A Case Study Of Friends Of The Koala, Nsw, Finley Scoular

Independent Study Project (ISP) Collection

Koala populations in New South Wales, Queensland, and the Australian Capital District are currently faced with factors that threaten their survival. Within one decade, their status has shifted from stable to vulnerable to endangered. The cause of this is attributed to increased exposure to dog attacks, vehicle collisions, diseases, and habitat fragmentation and destruction. The koalas' status of endangered in these territories has illuminated the need for human intervention. This study focuses on the specific form of human intervention that involves the rescue, rehabilitation, and release of wild koalas. Due to the recent koala status change from vulnerable to endangered, …

Patrimonio Cultural, Arqueología, Medio Ambiente Y Economía: ¿Cómo Ha Afectado La Construcción Del Aeropuerto Internacional De Chinchero-Cusco A Las Comunidades Y La Tierra De Chinchero?, Sydney Berenson

Independent Study Project (ISP) Collection

La urbanización gubernamental ha sido un problema para las poblaciones indígenas, el medio ambiente y la protección del patrimonio cultural durante numerosos años en todo el Perú. Más recientemente, en la pequeña ciudad de Chinchero, ubicada a unos 30 kilómetros al noroeste de Cusco, se está construyendo un nuevo aeropuerto internacional, Aeropuerto Internacional de Chinchero-Cusco (AICC), para reemplazar el actual aeropuerto nacional de Cusco. Chinchero es un importante centro urbano que está conformado por 13 comunidades campesinas que participan en la industria agrícola de la región, además consta con una importante comunidad artesanal, ruinas arqueológicas precolombinas y una gran biodiversidad. …

Við Pollurinn: The Effects Of Human-Caused Stimuli On Harbor Seals (Phoca Vitulina) In Ísafjörður, Ella Jorgensen

Independent Study Project (ISP) Collection

Harbor seals are important for the health of Iceland’s marine ecosystems. They are normally seen hauled-out onto land to rest. There are many factors that affect the haul-out patterns of harbor seals including location, season, time of day, tide height, weather, and human-caused stimuli. The presence of human-caused stimuli can also have a negative impact on haul-out patterns and behaviors. The Icelandic harbor seal population is threatened as it has been declining since 1980. Climate change and the rise of tourism in Iceland may be a factor contributing to this decline; and there is a gap in knowledge on the …

Carbon Storage Monitoring, Verification, And Accounting (Mva), University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet about carbon storage monitoring, verification, and accounting (MVA). Includes background on MVA, the Energy & Environmental Research Center, and Plains CO₂ Reduction (PCOR) Partnership plans for MVA strategy development.

General Brochure, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Information about the Energy & Environmental Research Center (EERC). Includes information on the EERC’s expertise, research priorities, facilities, and employment statistics.

Stprivacy: Spatio-Temporal Privacy-Preserving Action Recognition, Ming Li, Xiangyu Xu, Hehe Fan, Pan Zhou, Jun Liu, Jia-Wei Liu, Jiahe Li, Jussi Keppo, Mike Zheng Shou, Shuicheng Yan

Research Collection School Of Computing and Information Systems

Existing methods of privacy-preserving action recognition (PPAR) mainly focus on frame-level (spatial) privacy removal through 2D CNNs. Unfortunately, they have two major drawbacks. First, they may compromise temporal dynamics in input videos, which are critical for accurate action recognition. Second, they are vulnerable to practical attacking scenarios where attackers probe for privacy from an entire video rather than individual frames. To address these issues, we propose a novel framework STPrivacy to perform video-level PPAR. For the first time, we introduce vision Transformers into PPAR by treating a video as a tubelet sequence, and accordingly design two complementary mechanisms, i.e., sparsification …

Visilience: An Interactive Visualization Framework For Resilience Analysis Using Control-Flow Graph, Hailong Jiang, Shaolun Ruan, Bo Fang, Yong Wang, Qiang Guan

Research Collection School Of Computing and Information Systems

Soft errors have become one of the main concerns for the resilience of HPC applications, as these errors can cause HPC applications to generate serious outcomes such as silent data corruption (SDC). Many approaches have been proposed to analyze the resilience of HPC applications. However, existing studies rarely address the challenges of analysis result perception. Specifically, resilience analysis techniques often produce a massive volume of unstructured data, making it difficult for programmers to perform resilience analysis due to non-intuitive raw data. Furthermore, different analysis models produce diverse results with multiple levels of detail, which can create obstacles to compare and …

Modulation Of Electrocatalytic Activity By Tuning Anion Electronegativity: Case Study With Copper Chalcogenides, Harish Singh, David Prendergast, Manashi Nath

Chemistry Faculty Research & Creative Works

Anion-tuning in metallic chalcogenides has been shown to have a significant impact on their electrocatalytic ability for overall water splitting. In this article, copper-based chalcogenides (Cu2 X, X= O, S, Se, and Te) have been systematically studied to examine the effect of decreasing anion electronegativity and increasing covalency on the electrocatalytic performance. Among the copper chalcogenides, Cu2Te has the highest oxygen evolution reaction (OER) activity and can sustain high current density of 10 and 50 mA cm−2 for 12 h. The difference in intrinsic catalytic activity of these chalcogenide surfaces have been also probed through density functional theory calculations, which …

The Future Can't Help Fix The Past: Assessing Program Repair In The Wild, Vinay Kabadi, Dezhen Kong, Siyu Xie, Lingfeng Bao, Gede Artha Azriadi Prana, Tien Duy B. Le, Xuan Bach D. Le, David Lo

Research Collection School Of Computing and Information Systems

Automated program repair (APR) has been gaining ground with substantial effort devoted to the area, opening up many challenges and opportunities. One such challenge is that the state-of-the-art repair techniques often resort to incomplete specifications, e.g., test cases that witness buggy behavior, to generate repairs. In practice, bug-exposing test cases are often available when: (1) developers, at the same time of (or after) submitting bug fixes, create the tests to assure the correctness of the fixes, or (2) regression errors occur. The former case – a scenario commonly used for creating popular bug datasets – however, may not be suitable …

Computational Investigation Of Mononuclear Iron Water Oxidation Catalyst Design, Kristal Stevens, Emily Jarvis

Chemistry and Biochemistry Faculty Works

Hydrogen production from non-carbon sources is an essential component of clean and sustainable technology for reducing greenhouse gas emissions from fuels. Water oxidation, which splits water molecules into hydrogen (protons) and molecular oxygen, is a thermodynamically challenging, multistep reaction achieved in photosynthetic organisms via photocatalysis by the Oxygen Evolving Complex (OEC) of Photosystem II. Mononuclear water oxidation catalysts that aim to mimic nature typically rely on heavy, rare metals such as ruthenium and iridium. Replacing these metals with iron is particularly appealing because it is abundant, benign, and inexpensive. We use density functional theory to characterize the catalytic ability of …

Rough Numbers And Variations On The Erdős--Kac Theorem, Kai Fan

Dartmouth College Ph.D Dissertations

The study of arithmetic functions, functions with domain N and codomain C, has been a central topic in number theory. This work is dedicated to the study of the distribution of arithmetic functions of great interest in analytic and probabilistic number theory.

In the first part, we study the distribution of positive integers free of prime factors less than or equal to any given real number y>=1. Denoting by Phi(x,y) the count of these numbers up to any given x>=y, we show, by a combination of analytic methods and sieves, that Phi(x,y)<0.6x/\log y holds uniformly for all 3<=y<=sqrt{x}, improving upon an earlier result of the author in the same range. We also prove numerically explicit estimates of the de Bruijn type for Phi(x,y) which are applicable in wide ranges.

In the second part, we turn …