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Real-Time Rfi Mitigation In Radio Astronomy, Emily Ramey, Nick Joslyn, Richard Prestage, Michael Lam, Luke Hawkins, Tim Blattner, Mark Whitehead 2019 Washington University in St. Louis

Real-Time Rfi Mitigation In Radio Astronomy, Emily Ramey, Nick Joslyn, Richard Prestage, Michael Lam, Luke Hawkins, Tim Blattner, Mark Whitehead

Senior Honors Papers / Undergraduate Theses

As the use of wireless technology has increased around the world, Radio Frequency Interference (RFI) has become more and more of a problem for radio astronomers. Preventative measures exist to limit the presence of RFI, and programs exist to remove it from saved data, but the use of algorithms to detect and remove RFI as an observation is occurring is much less common. Such a method would be incredibly useful for observations in which the data must undergo several rounds of processing before being saved, as in pulsar timing studies. Strategies for real-time mitigation have been discussed and tested with ...


Stability Analysis Of A More General Class Of Systems With Delay-Dependent Coefficients, Chi Jin, Keqin Gu, Islam Boussaada, Silviu-Iulian Niculescu 2019 Laboratoire des Signaux et Syst`emes (L2S) CentraleSup´elec-CNRS-Universit´e Paris Sud, 3 rue Joliot- Curie 91192 Gif-sur-Yvette cedex, France.

Stability Analysis Of A More General Class Of Systems With Delay-Dependent Coefficients, Chi Jin, Keqin Gu, Islam Boussaada, Silviu-Iulian Niculescu

SIUE Faculty Research, Scholarship, and Creative Activity

This paper presents a systematic method to analyse the stability of systems with single delay in which the coefficient polynomials of the characteristic equation depend on the delay. Such systems often arise in, for example, life science and engineering systems. A method to analyze such systems was presented by Beretta and Kuang in a 2002 paper, but with some very restrictive assumptions. This work extends their results to the general case with the exception of some degenerate cases. It is found that a much richer behavior is possible when the restrictive assumptions are removed. The interval of interest for the ...


Potential Contamination Risk In Tennessee Aquifers From Oil And Gas Drilling, Emma Reed 2019 University of Tennessee

Potential Contamination Risk In Tennessee Aquifers From Oil And Gas Drilling, Emma Reed

University of Tennessee Honors Thesis Projects

No abstract provided.


Project Renew Worcester, Danni Yue, Amy Zhang, Jing Han, Omid Ashrafi, Yiming Xu 2018 Clark University

Project Renew Worcester, Danni Yue, Amy Zhang, Jing Han, Omid Ashrafi, Yiming Xu

School of Professional Studies

n The client for this capstone project is RENEW Worcester which is a fledgling solar power project whose main goals are to bring renewable energy in the form of solar power into local, primarily low-income communities and are committed to the mission of making the transition off of fossil fuels to clean, renewable power. Based in Worcester, Massachusetts, they are a local chapter of Co-op Power which is a consumer-owned sustainable energy cooperative (co-op) made up of numerous different local chapters all over the New England area as well as the state of New York. The problem that we will ...


Phr: Patient Health Record, Quinn Nelson 2018 University of Nebraska at Omaha

Phr: Patient Health Record, Quinn Nelson

Theses/Capstones/Creative Projects

The rapid development of information technology systems has expanded into multiple disciplines and results in systems that are limited by initial design and implementation: the Healthcare Information Technology (HIT) space is no different. The introduction of the Electronic Health Record (EHR) system has changed the way healthcare operates. Initial designs of these systems were focused on serving the needs of insurance companies and healthcare billing departments. Research shows that the design of EHR systems negatively impact provider-patient interactions and the care they receive. This capstone project capitalizes on the collaboration efforts between UNO and UNMC – by joining a research group ...


High-Performance Self-Powered Uv Detector Based On Sno2-Tio2 Nanomace Arrays, Duo Chen, Lin Wei, Lingpan Meng, Yanxue Chen, Yufeng Tian, Shishen Yan, Liangmo Mei, Jun Jiao 2018 School of Physics and State Key Laboratory of Crystal MaterialsShandong UniversityJinanPeople’s Republic of China

High-Performance Self-Powered Uv Detector Based On Sno2-Tio2 Nanomace Arrays, Duo Chen, Lin Wei, Lingpan Meng, Yanxue Chen, Yufeng Tian, Shishen Yan, Liangmo Mei, Jun Jiao

Physics Faculty Publications and Presentations

Photoelectrochemical cell-typed self-powered UV detectors have attracted intensive research interest due to their low cost, simple fabrication process, and fast response. In this paper, SnO2-TiO2 nanomace arrays composed of SnO2 nanotube trunk and TiO2 nanobranches were prepared using soft chemical methods, and an environment-friendly self-powered UV photodetector using this nanostructure as the photoanode was assembled. Due to the synergistic effect of greatly accelerated electron-hole separation, enhanced surface area, and reduced charge recombination provided by SnO2-TiO2 nanomace array, the nanostructured detector displays an excellent performance over that based on bare SnO2 arrays. The impact of the growing time of TiO2 branches ...


The Contribution Of Local And Transport Processes To Phytoplankton Biomass Variability Over Different Timescales In The Upper James River, Virginia, Qubin Qin, Jian Shen 2018 Virginia Institute of Marine Science

The Contribution Of Local And Transport Processes To Phytoplankton Biomass Variability Over Different Timescales In The Upper James River, Virginia, Qubin Qin, Jian Shen

Articles

Although both local processes (photosynthesis, respiration, grazing, and settling), and transport processes (advective transport and diffusive transport) significantly affect local phytoplankton dynamics, it is difficult to separate their contributions and to investigate the relative importance of each process to the local variability of phytoplankton biomass over different timescales. A method of using the transport rate is introduced to quantify the contribution of transport processes. By combining the time-varying transport rate and high-frequency observed chlorophyll a data, we can explicitly examine the impact of local and transport processes on phytoplankton biomass over a range of timescales from hourly to annually. For ...


Archean Phosphorus Liberation Induced By Iron Redox Geochemistry, Barry Herschy, Sae Jung Chang, Ruth Blake, Aivo Lepland, Heather Abbott-Lyon, Jacqueline Sampson, Zachary Atlas, Terence P. Kee, Matthew A. Pasek 2018 University of South Florida

Archean Phosphorus Liberation Induced By Iron Redox Geochemistry, Barry Herschy, Sae Jung Chang, Ruth Blake, Aivo Lepland, Heather Abbott-Lyon, Jacqueline Sampson, Zachary Atlas, Terence P. Kee, Matthew A. Pasek

Faculty Publications

The element phosphorus (P) is central to ecosystem growth and is proposed to be a limiting nutrient for life. The Archean ocean may have been strongly phosphorus-limited due to the selective binding of phosphate to iron oxyhydroxide. Here we report a new route to solubilizing phosphorus in the ancient oceans: reduction of phosphate to phosphite by iron(II) at low (<200 >°C) diagenetic temperatures. Reduction of phosphate to phosphite was likely widespread in the Archean, as the reaction occurs rapidly and is demonstrated from thermochemical modeling, experimental analogs, and detection of phosphite in early Archean rocks. We further demonstrate that the ...


Exploring Multiple Operating Scenarios To Identify Low-Cost, High Nitrate Removal Strategies For Electrically-Stimulated Woodchip Bioreactors, Ji-Yeow Law, Michelle L. Soupir, D. Raj Raman, Thomas Moorman 2018 Iowa State University

Exploring Multiple Operating Scenarios To Identify Low-Cost, High Nitrate Removal Strategies For Electrically-Stimulated Woodchip Bioreactors, Ji-Yeow Law, Michelle L. Soupir, D. Raj Raman, Thomas Moorman

Agricultural and Biosystems Engineering Publications

Woodchip bioreactors are recognized as an effective best management practice in the Iowa Nutrient Reduction Strategy. This edge-of-field practice intercepts and removes NO3-N, thereby reducing the NO3-N concentration in tile drainage before being discharged into surface water. Actual NO3-N load reductions realized by woodchip bioreactors are impacted by bioreactor size, hydraulic retention time (HRT), and denitrification efficiency. A typical woodchip bioreactor in Iowa may have 0.07% bioreactor area with respect to treatment area, 4–8 h HRT, and 43% mean denitrification efficiency. Here, we explored the potential of using electrically stimulated woodchip bioreactors to achieve greater NO3-N removal, and ...


Characterization And Quantification Of Covalent Modification Of Proteins Using Mass Spectrometry, Pratikkumar N. Rathod 2018 The Graduate Center, City University of New York

Characterization And Quantification Of Covalent Modification Of Proteins Using Mass Spectrometry, Pratikkumar N. Rathod

All Dissertations, Theses, and Capstone Projects

Identification and characterization of various post-translational modifications of protein is a key to understanding many unknown cellular processes. In the last few decades, mass spectrometry has evolved as an essential and effective analytical tool for qualitative and quantitative analysis of proteins. In this research, we have developed a novel MALDI-MS2 based quantification method for Desmosine and Isodesmosine, which served as cross-linking amino acids of elastin, in order to measure the elastin degradation in the body. This is the first quantification method that not only illustrates the potential of MALDI-Ion Trap MS2, but also improvement over the current LC-MS ...


Security And Privacy In Smart Health: Efficient Policy-Hiding Attribute-Based Access Control, Yinghui ZHANG, Dong ZHENG, Robert H. DENG 2018 Singapore Management University

Security And Privacy In Smart Health: Efficient Policy-Hiding Attribute-Based Access Control, Yinghui Zhang, Dong Zheng, Robert H. Deng

Research Collection School Of Information Systems

With the rapid development of the Internet of Things (IoT) and cloud computing technologies, smart health (s-health) is expected to significantly improve the quality of health care. However, data security and user privacy concerns in s-health have not been adequately addressed. As a well-received solution to realize fine-grained access control, ciphertext-policy attribute-based encryption (CP-ABE) has the potential to ensure data security in s-health. Nevertheless, direct adoption of the traditional CP-ABE in s-health suffers two flaws. For one thing, access policies are in cleartext form and reveal sensitive health-related information in the encrypted s-health records (SHRs). For another, it usually supports ...


Domain-Specific Knowledge Exploration With Ontology Hierarchical Re-Ranking And Adaptive Learning And Extension, Grace G. Zhao 2018 The Graduate Center, City University of New York

Domain-Specific Knowledge Exploration With Ontology Hierarchical Re-Ranking And Adaptive Learning And Extension, Grace G. Zhao

All Dissertations, Theses, and Capstone Projects

The goal of this research project is the realization of an artificial intelligence-driven lightweight domain knowledge search framework that returns a domain knowledge structure upon request with highly relevant web resources via a set of domain-centric re-ranking algorithms and adaptive ontology learning models. The re-ranking algorithm, a necessary mechanism to counter-play the heterogeneity and unstructured nature of web data, uses augmented queries and a hierarchical taxonomic structure to get further insight into the initial search results obtained from credited generic search engines. A semantic weight scale is applied to each node in the ontology graph and in turn generates a ...


Quantum And Classical Transport Of 2d Electrons In The Presence Of Long And Short Range Disorder, Jesse Kanter 2018 The Graduate Center, City University of New York

Quantum And Classical Transport Of 2d Electrons In The Presence Of Long And Short Range Disorder, Jesse Kanter

All Dissertations, Theses, and Capstone Projects

This work focuses on the study of electron transport of 2-D electron gas systems in relation to both fundamental properties of the systems such as disorder and scattering mechanisms, as well as unique magnetoresistance (MR) effects. A large portion of the discussion is built around the use of an in plane magnetic field to vary the ratio between the Zeeman energy between electrons of different spins and the Landau level spacing, creating a tool to control the quantization of the density of states (DOS).

This tool is first used to isolate Quantum Positive Magnetoresistance (QPMR), which grants insight to the ...


Rationality And Efficient Verifiable Computation, Matteo Campanelli 2018 The Graduate Center, City University of New York

Rationality And Efficient Verifiable Computation, Matteo Campanelli

All Dissertations, Theses, and Capstone Projects

In this thesis, we study protocols for delegating computation in a model where one of the parties is rational. In our model, a delegator outsources the computation of a function f on input x to a worker, who receives a (possibly monetary) reward. Our goal is to design very efficient delegation schemes where a worker is economically incentivized to provide the correct result f(x). In this work we strive for not relying on cryptographic assumptions, in particular our results do not require the existence of one-way functions.

We provide several results within the framework of rational proofs introduced by ...


Using Cogenerative Dialogue To Catalyse Change, Carol A. Woodburn-McDonald 2018 The Graduate Center, City University of New York

Using Cogenerative Dialogue To Catalyse Change, Carol A. Woodburn-Mcdonald

All Dissertations, Theses, and Capstone Projects

Cogenerative dialogue is an empowering pedagogical approach to advance research. In my study cogenerative dialogue and coteaching were employed in an algebra 1 class in an urban high school in New York City. Lessons were cotaught with students and were videotaped for further analysis. The findings suggest that cogens constitute an excellent avenue to catalyze change in an urban algebra class.


A Linked Coptic Dictionary Online, Frank Feder, Maxim Kupreyev, Emma Manning, Caroline T. Schroeder, Amir Zeldes 2018 Akademie der Wissenschaften zu Göttingen

A Linked Coptic Dictionary Online, Frank Feder, Maxim Kupreyev, Emma Manning, Caroline T. Schroeder, Amir Zeldes

College of the Pacific Faculty Presentations

We describe a new project publishing a freely available online dictionary for Coptic. The dictionary encompasses comprehensive cross-referencing mechanisms, including linking entries to an online scanned edition of Crum’s Coptic Dictionary, internal cross-references and etymological information, translated searchable definitions in English, French and German, and linked corpus data which provides frequencies and corpus look-up for headwords and multiword expressions. Headwords are available for linking in external projects using a REST API. We describe the challenges in encoding our dictionary using TEI XML and implementing linking mechanisms to construct a Web interface querying frequency information, which draw on NLP tools ...


Evaluation Of Blight Resistance In Chestnut F2 Half-Sibling And Full-Sibling Families Via Small Stem Assay, Kevin Gentner 2018 University of Tennessee at Chattanooga

Evaluation Of Blight Resistance In Chestnut F2 Half-Sibling And Full-Sibling Families Via Small Stem Assay, Kevin Gentner

Honors Theses

In 1904, Cryphonectria parasitica, the causal agent for chestnut blight, was imported into North America on chestnut nursery stock from China. Fifty-five years later, nearly all full-grown wild American chestnut trees (Castanea dentata) were dead. A century of work has been put into restoring the American chestnut to its rightful place among the forest canopy. Since the 1980s, The American Chestnut Foundation has pursued backcross breeding to introgress blight resistance into C. dentata from the resistant Chinese species (C. mollissima), and has used progeny testing to make predictions about parental resistance in B3F2 chestnuts. We performed a small stem assay ...


Creating A Better Technological Piano Practice Aid With Knowledge Tracing, Max Feldkamp 2018 University of Colorado, Boulder

Creating A Better Technological Piano Practice Aid With Knowledge Tracing, Max Feldkamp

Keyboard Graduate Theses & Dissertations

Modern music tutoring software and mobile instructional applications have great potential to help students practice at home effectively. They can offer extensive feedback on what the student is getting right and wrong and have adopted a gamified design with levels, badges, and other game-like elements to help gain wider appeal among students. Despite their advantages for motivating students and creating a safe practice environment, no current music instruction software demonstrates any knowledge about a student’s level of mastery. This can lead to awkward pedagogy and user frustration. Applying Bayesian Knowledge Tracing to tutoring systems provides an ideal way to ...


A Comparison Of R, Sas, And Python Implementations Of Random Forests, Breckell Soifua 2018 Utah State University

A Comparison Of R, Sas, And Python Implementations Of Random Forests, Breckell Soifua

All Graduate Plan B and other Reports

The Random Forest method is a useful machine learning tool developed by Leo Breiman. There are many existing implementations across different programming languages; the most popular of which exist in R, SAS, and Python. In this paper, we conduct a comprehensive comparison of these implementations with regards to the accuracy, variable importance measurements, and timing. This comparison was done on a variety of real and simulated data with different classification difficulty levels, number of predictors, and sample sizes. The comparison shows unexpectedly different results between the three implementations.


Why Do They Do That? Understanding Factors Influencing Visitor Spatial Behavior In Parks And Protected Areas, Abigail M. Sisneros-Kidd 2018 Utah State University

Why Do They Do That? Understanding Factors Influencing Visitor Spatial Behavior In Parks And Protected Areas, Abigail M. Sisneros-Kidd

All Graduate Theses and Dissertations

Visitors to parks and protected areas within the United States and worldwide often visit these areas with a particular destination in mind, such as seeing Old Faithful erupt in Yellowstone National Park or standing on the rim of the Grand Canyon in Grand Canyon National Park. These visitor use destinations, and the pathways leading to them, such as trails and roadways, see high levels of use, and as a result, impacts to soil, vegetation, air, water, soundscapes, and night skies that result from this use. The field of recreation ecology studies these impacts to park and protected area resources resulting ...


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