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Articles 27271 - 27300 of 302419

Full-Text Articles in Physical Sciences and Mathematics

A Lite Daq System For Precision Resistance Measurements, Nathan Schmidt, Timothy E. Kidd Ph.D. Jul 2022

A Lite Daq System For Precision Resistance Measurements, Nathan Schmidt, Timothy E. Kidd Ph.D.

Summer Undergraduate Research Program (SURP) Symposium

Data acquisition (DAQ) systems are frequently utilized in lab settings. Basic DAQ systems are a common occurrence in lab courses for this reason. Commonly, however, the DAQ systems utilized in such courses are proprietary, and do not allow students to understand how they operate beyond a “plug in and go” nature as a result. A further consequence is that these systems are not capable of being programmed, such as is often done with equipment used in professional labs. The DAQ systems used in lab courses aren’t easily replaced by the test equipment they seek to emulate due to cost. Ideally, …


Geoenvironmental Implications On Food Sovereignty - Meskwaki Settlement, Tama County, Iowa, Lindsey Hubbell, Chad Heinzel Ph.D., Christina Blackcloud, Luke Kapayou, Avis Bear-Bass Jul 2022

Geoenvironmental Implications On Food Sovereignty - Meskwaki Settlement, Tama County, Iowa, Lindsey Hubbell, Chad Heinzel Ph.D., Christina Blackcloud, Luke Kapayou, Avis Bear-Bass

Summer Undergraduate Research Program (SURP) Symposium

Native American culture demonstrates a spiritual relationship to food, land, and Earth. As opposed to European traditions valuing private property and exploiting the Earth for profit, Native American tradition believes the Earth is owned by no one; food and nourishment from it are a gift for all to take only as needed. The Meskwaki Nation originated around the Great Lakes but was removed to Tama County, Iowa. It is derived from the words “Meskwa” meaning “red” and “aki” meaning “Earth”. This Red Earth nation has initiated a Food Sovereignty program to pass along traditional growing and food preparation practices to …


Rendezvous Numbers Of Compact And Connected Spaces, Kevin Demler, Bill Wood Ph.D. Jul 2022

Rendezvous Numbers Of Compact And Connected Spaces, Kevin Demler, Bill Wood Ph.D.

Summer Undergraduate Research Program (SURP) Symposium

The concept of a rendezvous number was originally developed by O. Gross in 1964, and was expanded upon greatly by J. Cleary, S. Morris, and D. Yost in 1986. This number exists for every metric space, yet very little is known about it, and it’s exact value for most spaces is not known. Furthermore, it’s exact value is difficult to calculate, and in most cases we can only find bounds for the value. We focused on their arguments using convexity and applied it to shapes in different metrics and graphs. Using sets of points that stood out (vertices, midpoints) as …


Ultra-Flat Au Surfaces On Finite Layer Mos2, Jeff Carlson, Timothy E. Kidd Ph.D., Andrew J. Stollenwerk Ph.D. Jul 2022

Ultra-Flat Au Surfaces On Finite Layer Mos2, Jeff Carlson, Timothy E. Kidd Ph.D., Andrew J. Stollenwerk Ph.D.

Summer Undergraduate Research Program (SURP) Symposium

We have developed a method for creating ultra-flat Au surfaces by sputtering Au onto thin films of MoS2. This method is more cost effective than current technologies. Our Au surfaces are subatomically flat over relatively large areas making them useful for self assembled monolayer (SAM) research.


Pilot Study: Geoenvironmental Controls Of Residential Radon Cedar Falls, Iowa, Maya Mallavarapu, Chad Heinzel Ph.D. Jul 2022

Pilot Study: Geoenvironmental Controls Of Residential Radon Cedar Falls, Iowa, Maya Mallavarapu, Chad Heinzel Ph.D.

Summer Undergraduate Research Program (SURP) Symposium

  • The leading cause of lung-cancer for individuals who do not smoke is exposure to abnormally high radon concentrations. If radon concentrations within a person’s basement is above 4 pCi/L, the EPA recommends further testing and possible decontamination of the area to mitigate one’s exposure to radon.
  • Radon is a radioactive gas that originates from the decay series of Uranium-238. The decay series begins with Uranium-238 and finishes with an end product of Lead-206. However, during this decay process before Lead-206 is culminated, intermediates such as Uranium-234, Thorium-230, Radium-226, and Radon-222 are also produced


Development Of A Water Quality Index Calculation Tool Using Excel, Rowan Mccarthy, Mohammad Iqbal Ph.D. Jul 2022

Development Of A Water Quality Index Calculation Tool Using Excel, Rowan Mccarthy, Mohammad Iqbal Ph.D.

Summer Undergraduate Research Program (SURP) Symposium

With many parameters by which water can be measured, it can be difficult to understand whether water is high quality or low quality. To solve this problem, many water quality indices have been developed over the last 60 years. The UNI Hydrology Lab uses the National Sanitation Foundation Water Quality Index (NSFWQI). This index provides a methodology by which Dissolved Oxygen, Fecal Coliform, pH, Biochemical Oxygen Demand, Temperature Change, Total Phosphate, Nitrate, Turbidity, and Total Solids can be combined to provide a single number indicative of the overall water quality. In previous years, when WQI calculations were needed, the bulk …


Left-Separation Of Ω1, Lukas Stuelke, Adrienne Stanley Ph.D. Jul 2022

Left-Separation Of Ω1, Lukas Stuelke, Adrienne Stanley Ph.D.

Summer Undergraduate Research Program (SURP) Symposium

A topological space is left-separated if it can be well-ordered so that every initial segment is closed. Here, we show that all countable ordinal numbers are left-separated. We then prove that a similar method could not work for ω1 , using the pressing-down lemma1 . We finish by showing that a left-separating well-ordering on ω1 necessarily leads to a contradiction.


Using Remote And In Situ Observations From Torus To Investigate A Preexisting Airmass Boundary And Its Influence On A Tornadic Supercell On 28 May 2019, Kristen Axon Jul 2022

Using Remote And In Situ Observations From Torus To Investigate A Preexisting Airmass Boundary And Its Influence On A Tornadic Supercell On 28 May 2019, Kristen Axon

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

During the 2019 field phase of Targeted Observation by Radars and UAS of Supercells (TORUS), a preexisting airmass boundary was sampled on 28 May 2019 in north-central Kansas in close proximity to a tornadic supercell. This work hypothesized that the preexisting airmass boundary was associated with a mesoscale air mass with high theta-E (MAHTE) that favorably interacted with the tornadic supercell to increase the likelihood of tornadogenesis. Observations from TORUS including mobile mesonets, unoccupied aerial vehicles, soundings, and ground-based mobile radar were used along with GOES-16 visible satellite imagery, Kansas mesonet surface stations, and KUEX WSR-88D data to investigate this …


Majorana Bound States With Chiral Magnetic Textures, Utkan Güngördü, Alexey Kovalev Jul 2022

Majorana Bound States With Chiral Magnetic Textures, Utkan Güngördü, Alexey Kovalev

Alexey Kovalev Papers

The aim of this Tutorial is to give a pedagogical introduction into realizations of Majorana fermions, usually termed as Majorana bound states (MBSs), in condensed matter systems with magnetic textures. We begin by considering the Kitaev chain model of “spinless” fermions and show how two “half” fermions can appear at chain ends due to interactions. By considering this model and its two-dimensional generalization, we emphasize intricate relation between topological superconductivity and possible realizations of MBS. We further discuss how “spinless” fermions can be realized in more physical systems, e.g., by employing the spin-momentum locking. Next, we demonstrate how magnetic textures …


61st Annual Rocky Mountain Conference On Magnetic Resonance Jul 2022

61st Annual Rocky Mountain Conference On Magnetic Resonance

Rocky Mountain Conference on Magnetic Resonance

Final program, abstracts, and information about the 61st annual meeting of the Rocky Mountain Conference on Magnetic Resonance, co-endorsed by the Colorado Section of the American Chemical Society and the Society for Applied Spectroscopy. Held in Copper Mountain, Colorado, July 25-29, 2022.


Majorana Bound States With Chiral Magnetic Textures, Utkan Güngördü, Alexey Kovalev Jul 2022

Majorana Bound States With Chiral Magnetic Textures, Utkan Güngördü, Alexey Kovalev

Department of Physics and Astronomy: Faculty Publications

The aim of this Tutorial is to give a pedagogical introduction into realizations of Majorana fermions, usually termed as Majorana bound states (MBSs), in condensed matter systems with magnetic textures. We begin by considering the Kitaev chain model of “spinless” fermions and show how two “half” fermions can appear at chain ends due to interactions. By considering this model and its two-dimensional generalization, we emphasize intricate relation between topological superconductivity and possible realizations of MBS. We further discuss how “spinless” fermions can be realized in more physical systems, e.g., by employing the spin-momentum locking. Next, we demonstrate how magnetic textures …


Deep Reinforcement Learning For End-To-End Network Slicing: Challenges And Solutions, Qiang Liu, Nakjung Choi, Tao Han Jul 2022

Deep Reinforcement Learning For End-To-End Network Slicing: Challenges And Solutions, Qiang Liu, Nakjung Choi, Tao Han

School of Computing: Faculty Publications

5G and beyond is expected to enable various emerging use cases with diverse performance requirements from vertical industries. To serve these use cases cost-effectively, network slicing plays a key role in dynamically creating virtual end-to-end networks according to specific resource demands. A network slice may have hundreds of configurable parameters over multiple technical domains that define the performance of the network slice, which makes it impossible to use traditional model-based solutions to orchestrate resources for network slices. In this article, we discuss how to design and deploy deep reinforcement learning (DRL), a model-free approach, to address the network slicing problem. …


Resonant Energy Exchange In Ultracold Rydberg Atoms, Samantha Grubb, Alan Okinaka Jul 2022

Resonant Energy Exchange In Ultracold Rydberg Atoms, Samantha Grubb, Alan Okinaka

Physics and Astronomy Summer Fellows

Ultracold Rydberg atoms serve as good systems in which resonant dipole-dipole interactions can be observed. The goal of our work is to design a simulation in which energy exchange among many nearly evenly spaced energy levels is observed. These observations are useful for understanding the time evolution of complicated quantum systems, and have applications in quantum computing and simulating. We are utilizing a supercomputer to run our simulation as well as studying the system experimentally. Once we obtain simulated results, we plan to compare them with the results obtained in a lab.


Maintaining Ecosystem And Economic Structure In A Three-Species Dynamical System In Chesapeake Bay, Maila Hallare, Iordanka Panayotova Jul 2022

Maintaining Ecosystem And Economic Structure In A Three-Species Dynamical System In Chesapeake Bay, Maila Hallare, Iordanka Panayotova

CODEE Journal

We consider a three-species fish dynamical system in Chesapeake Bay consisting of the Atlantic menhaden as the prey and its two competing predators, the striped bass and the catfish. Building on our previous work in this system, we consider the issue of balancing economic harvesting goals (financial gain for fishermen) with ecological harvesting goals (non-extinction of species). In particular, we investigate the bionomic equilibria, maximum sustainable yield, and the maximum economic yield. Analytical computations and numerical simulations are employed to provide some mathematical guidance on fisheries management policies.


Butte Priority Soils Operable Unit (Bpsou) Revised Final Residential Metals Abatement Program (Rmap) Plan, Mike Mcanulty Jul 2022

Butte Priority Soils Operable Unit (Bpsou) Revised Final Residential Metals Abatement Program (Rmap) Plan, Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Re: Butte Priority Soils Operable Unit (Bpsou) Revised Final Residential Metals Abatement Program (Rmap) Plan, Mike Mcanulty Jul 2022

Re: Butte Priority Soils Operable Unit (Bpsou) Revised Final Residential Metals Abatement Program (Rmap) Plan, Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Final Bpsou Insufficiently Reclaimed Sites Colorado Dump-West Lot Remedial Action Work Plan (Rawp), Pioneer Technical Services, Inc. Jul 2022

Final Bpsou Insufficiently Reclaimed Sites Colorado Dump-West Lot Remedial Action Work Plan (Rawp), Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


2022 Final Insufficiently Reclaimed Sites Quality Assurance Project Plan (Qapp), Pioneer Technical Services, Inc. Jul 2022

2022 Final Insufficiently Reclaimed Sites Quality Assurance Project Plan (Qapp), Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Butte Priority Soils Operable Unit (Bpsou) Final Insufficiently Reclaimed Sites - Field Sampling Plan (Fsp) Bres No. 32 – Corra-2 Dumps, Mike Mcanulty Jul 2022

Butte Priority Soils Operable Unit (Bpsou) Final Insufficiently Reclaimed Sites - Field Sampling Plan (Fsp) Bres No. 32 – Corra-2 Dumps, Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Butte Priority Soils Operable Unit (Bpsou) Final Insufficiently Reclaimed Sites - Field Sampling Plan (Fsp) Bres No. 37 – Josephine Shaft, Mike Mcanulty Jul 2022

Butte Priority Soils Operable Unit (Bpsou) Final Insufficiently Reclaimed Sites - Field Sampling Plan (Fsp) Bres No. 37 – Josephine Shaft, Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


2022 Final Insufficiently Reclaimed Sites Quality Assurance Project Plan (Qapp), Pioneer Technical Services, Inc. Jul 2022

2022 Final Insufficiently Reclaimed Sites Quality Assurance Project Plan (Qapp), Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Revisit Of Open Clusters Upk 39, Upk 41 And Phoc 39 : A New Binary Open Cluster Found, Xianhao Ye, Terry D. Oswalt, Jingkun Zhao, Yong Yang, Gang Zhao Jul 2022

Revisit Of Open Clusters Upk 39, Upk 41 And Phoc 39 : A New Binary Open Cluster Found, Xianhao Ye, Terry D. Oswalt, Jingkun Zhao, Yong Yang, Gang Zhao

Publications

We investigate the three open clusters near Aquila Rift cloud, named as UPK 39 (c1 hereafter), UPK 41 (c2 hereafter) in Sim et al. (2019) and PHOC 39 (c3 hereafter) in Hunt & Reffert (2021), respectively. Using photometric passpands, reddening, and extinction from Gaia DR3, we construct the color-absolute-magnitude diagram (CAMD). Using isochrone fits their ages are estimated as 6.3 ± 0.9, 8.1 ± 1.4 and 21.8 ± 2.2 Myr, respectively. Their proper motions and radial velocities, estimated using data from Gaia and LAMOST are very similar. From their orbits, relative distances among them at different times, kinematics, ages, and …


Response To Comments For Butte Priority Soils Operable Unit (Bpsou) Draft Final Street And Snow Management Plan (Received December 15, 2021), Mike Mcanulty Jul 2022

Response To Comments For Butte Priority Soils Operable Unit (Bpsou) Draft Final Street And Snow Management Plan (Received December 15, 2021), Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Weakness Of Weak Values: Incompatibility Of Anomalous Pulse-Spectrum Amplification And Optical Frequency Combs, John C. Howell Jul 2022

Weakness Of Weak Values: Incompatibility Of Anomalous Pulse-Spectrum Amplification And Optical Frequency Combs, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We probe the use of optical frequency combs to place lower bounds on anomalous amplification of a weak-value-measured pulse delay, potentially reaching a theoretical temporal resolution of better than 10−34 s. Owing to the interferometric behavior of weak values, we show that anomalous weak value amplification of a time delay is not equivalent to a temporal linear phase ramp. We show that the anomalous weak value is a rearrangement of amplitudes that generates an apparent shift that can be measured in direct detection, but does not change the actual frequency offset of a spectral distribution measurable in coherent detection. …


Reputation-Based Trust Assessment Of Transacting Service Components, Konstantinos Tsiounis Jul 2022

Reputation-Based Trust Assessment Of Transacting Service Components, Konstantinos Tsiounis

Electronic Thesis and Dissertation Repository

As Service-Oriented Systems rely for their operation on many different, and most often, distributed software components, a key issue that emerges is how one component can trust the services offered by another component. Here, the concept of trust is considered in the context of reputation systems and is viewed as a meta-requirement, that is, the level of belief a service requestor has that a service provider will provide the service in a way that meets the requestor’s expectations. We refer to the service offering components as service providers (SPs) and the service requesting components as service clients (SCs).

In this …


Characterization Of Some Natural Copper Samples From The Keweenaw Peninsula Of Lake Superior Using Electron Microscopy And X-Ray Tomography Techniques, Emilie Mk Landry Jul 2022

Characterization Of Some Natural Copper Samples From The Keweenaw Peninsula Of Lake Superior Using Electron Microscopy And X-Ray Tomography Techniques, Emilie Mk Landry

Electronic Thesis and Dissertation Repository

Copper corrosion is of interest to Canada’s Nuclear Waste Management Organization as it relates to their multi-barrier system for nuclear waste disposal in deep geologic repositories. Spent fuel canisters coated with a thin copper layer must persist for up to one million years. Natural copper from the Keweenaw Peninsula in Michigan, USA, has persisted for over 1 billion years and is here characterized to understand copper corrosion over geological time. Copper samples representing three rock types were characterized using optical microscopy, scanning electron microscopy techniques (energy dispersive X-ray spectroscopy and electron backscatter diffraction), and micro-computed X-ray tomography (microCT) to establish …


Coupling Dendrochronology And Remote Sensing Techniques To Assess The Biophysical Traits Of Juniperus Virginiana And Pinus Ponderosa Within Grassland Communities In The Semi-Arid Grasslands Of The Nebraska Sandhills, Reece Allen Jul 2022

Coupling Dendrochronology And Remote Sensing Techniques To Assess The Biophysical Traits Of Juniperus Virginiana And Pinus Ponderosa Within Grassland Communities In The Semi-Arid Grasslands Of The Nebraska Sandhills, Reece Allen

School of Natural Resources: Dissertations, Theses, and Student Research

Woody species encroachment is occurring within the sandhills region in Nebraska, primarily driven by Juniperus virginiana and Pinus ponderosa, altering ecosystems and the services they provide. Effective, low cost, and cross-scale monitoring of woody species growth and performance is necessary for integrated grassland and forest management in the face of climate variability and change. In this study, we sought to establish a relationship between remote sensing-derived vegetation indices (VIs) and dendrochronological (raw and standardized tree ring width) measurements to assess the performance of encroaching woody J. virginiana and P. ponderosa located within the Nebraska National Forest in the sandhills. …


Semantic-Aligned Matching For Enhanced Detr Convergence And Multi-Scale Feature Fusion, Gongjie Zhang, Zhipeng Luo, Yingchen Yu, Jiaxing Huang, Kaiwen Cui, Shijian Lu, Eric Xing Jul 2022

Semantic-Aligned Matching For Enhanced Detr Convergence And Multi-Scale Feature Fusion, Gongjie Zhang, Zhipeng Luo, Yingchen Yu, Jiaxing Huang, Kaiwen Cui, Shijian Lu, Eric Xing

Machine Learning Faculty Publications

The recently proposed DEtection TRansformer (DETR) has established a fully end-to-end paradigm for object detection. However, DETR suffers from slow training convergence, which hinders its applicability to various detection tasks. We observe that DETR's slow convergence is largely attributed to the difficulty in matching object queries to relevant regions due to the unaligned semantics between object queries and encoded image features. With this observation, we design Semantic-Aligned-Matching DETR++ (SAM-DETR++) to accelerate DETR's convergence and improve detection performance. The core of SAM-DETR++ is a plug-andplay module that projects object queries and encoded image features into the same feature embedding space, where …


Haemosporidian Parasite Diversity In An Under-Surveyed Australian Avifauna, Ian R. Hoppe, Allison E. Johnson, Elizabeth Vanwormer Jul 2022

Haemosporidian Parasite Diversity In An Under-Surveyed Australian Avifauna, Ian R. Hoppe, Allison E. Johnson, Elizabeth Vanwormer

School of Natural Resources: Faculty Publications

Haemosporidian parasites of birds are geographically widespread, have been detected in a phylogenetically diverse array of hosts, and have been the focus of extensive research due to both their impacts on birds and their similarity to vector-borne diseases of humans. Advances in molecular diagnostic tools have created a greater awareness of the genetic diversity of haemosporidian infections. Yet in spite of their more or less global distribution, comparatively little is known about the haemosporidians affecting birds in Australia. We screened blood from 889 birds (23 species) for haemosporidian blood parasite infections during the 2019 breeding season at Brookfield Conservation Park, …


Changes In Nonlinearity And Stability Of Streamflow Recession Characteristics Under Climate Warming In A Large Glaciated Basin Of The Tibetan Plateau, Jiarong Wang, Xi Chen, Man Gao, Qi Hu, Jintao Liu Jul 2022

Changes In Nonlinearity And Stability Of Streamflow Recession Characteristics Under Climate Warming In A Large Glaciated Basin Of The Tibetan Plateau, Jiarong Wang, Xi Chen, Man Gao, Qi Hu, Jintao Liu

School of Natural Resources: Faculty Publications

The accelerated climate warming in the Tibetan Plateau after 1997 has profound consequences in hydrology, geography, and social wellbeing. In hydrology, the change in streamflow as a result of changes in dynamic water storage that originated from glacier melt and permafrost thawing in the warming climate directly affects the available water resources for societies of the most populated nations in the world. In this study, annual streamflow recession characteristics are analyzed using daily climate and hydrological data during 1980–2015 in the Yarlung Zangbo River basin (YRB) of the southern Tibetan Plateau. The recession characteristics are examined in terms of dQ=dt …