Physical Sciences and Mathematics Commons^™

Studies On Effect Of Intercropping Forage Grasses In Young Forestries On The Hilly Areas In South China, Keyun Li, Kexin Liu, Lingling He

IGC Proceedings (1993-2023)

No abstract provided.

Genetic Study On The Biological Characteristics Of F1 Hybrids Between Sorghum Bicolor And Sorghum Sudanense, Haiming Zhao, Nan Xie, Yuan Li, Guibo Liu

IGC Proceedings (1993-2023)

No abstract provided.

Dendrolobium Spp. — A Source Of Tropical Multipurpose Legumes, R. Schultze‐Kraft, M. Peters, L. H. Franco, B. Hincapié

IGC Proceedings (1993-2023)

No abstract provided.

Non-Linear Effects Of Solution Parameters And Gamma Radiation On Nickel Oxidation Dynamics, Razieh Karimihaghighi

Electronic Thesis and Dissertation Repository

Nickel is the main component in nickel-based superalloys which are known for their superior corrosion resistance and mechanical properties. These alloys are used in nuclear power plants, mainly for thin-walled heat exchanger tubing where these materials are exposed to a continuous flux of ionizing radiation. The long-term corrosion behaviour of these alloys at high temperatures and in the presence of gamma-radiation is not well understood. Moreover, the mechanism by which nickel improves the corrosion resistance of these alloys is also not known. Therefore, a mechanistic understanding of the nickel oxidation process is required to develop a predictive corrosion model for …

Optimizing Fluorescence Pmt Gain And Excitation Wavelength For Hplc Dl-Amino Acid Detection, Daranthea Amanda Atmadja, Aaron Jacobs

Honors Scholars & Undergraduate Research Poster Symposium Programs

Amino acids exist as enantiomers that can be separated and detected using HPLC-FLD. An optimal PMT gain and wavelength of excitation must be determined to lower the limit of detection (LOD) and quantitation (LOQ) as increasing the PMT gain amplifies the signal on the HPLC-Spectra. The HPLC-FLD spectra of OPA-IBLC derivatized histidine was measured at PMT gain 5 and 7 for the excitation wavelengths of 340-, 260-, and 240- nm. Hence, the optimal excitation wavelength and PMT gain can be determined by comparing the fluorescence spectra.

Past, Present, And Future– A Review Of Berrien County Water And Great Lakes Water Resources And Quality, Jongwan Bae

Honors Scholars & Undergraduate Research Poster Symposium Programs

The decrease in water quality for environmental and drinking water has been prevalent in the Great Lakes region, where industrialization, agricultural development, and population increase have contributed substantially. Looking through historical reports and the present, the degradation in water quality will likely continue. Our research intends to use inductively coupled plasma atomic emission spectroscopy to create a methodology to quantitatively detect various heavy metals and other elements from any water source. Current research has been on the determination of a niche in water testing and the creation of an infographic, as well as data of simple water samples.

Copper (Ii) Sequestration By Pamam Dendrimers In Tap Water, Hannah Castillo

Honors Scholars & Undergraduate Research Poster Symposium Programs

Dendrimers are nanomaterials that are widely studied for a variety of applications because of their distinctive properties. One such property of, specifically, the generation 2-PAMAM Dendrimer is its particular affinity for copper (II) ions. This could be influential in selective heavy metal extraction, particularly in contaminated water. Our research aims to test the sequestration and selectivity of PAMAM dendrimers with amine surface groups for copper (II) ions in a chemical environment with interfering species, such as tap water, using Inductively Coupled Plasma spectroscopy. Ongoing research has involved developing methods for dendrimer extractions and creating calibration curves for standards to ensure …

Entropic Dynamics Of Networks, Felipe Xavier Costa, Pedro Pessoa

Northeast Journal of Complex Systems (NEJCS)

Here we present the entropic dynamics formalism for networks. That is, a framework for the dynamics of graphs meant to represent a network derived from the principle of maximum entropy and the rate of transition is obtained taking into account the natural information geometry of probability distributions. We apply this framework to the Gibbs distribution of random graphs obtained with constraints on the node connectivity. The information geometry for this graph ensemble is calculated and the dynamical process is obtained as a diffusion equation. We compare the steady state of this dynamics to degree distributions found on real-world networks.

Determining The Origins Of Helix Glitches In Ligo’S H1 Detector, Kara Shepard

Honors Scholars & Undergraduate Research Poster Symposium Programs

The LIGO detectors are ultra-sensitive, making them susceptible to glitches from the noise that can block gravitational wave signals. In order to reduce the number of glitches that occur in the detector, the cause of the glitches must be found. I am researching the Helix glitch to try and determine its origin. This is accomplished by studying the times at which the glitch occurred in the detector and then looking for factors that may have caused a glitch to happen around the same time, to see if there are any correlations.

Emergent Hierarchy Through Conductance-Based Degree Constraints, Christopher Tyler Diggans, Jeremie Fish, Erik M. Bollt

Northeast Journal of Complex Systems (NEJCS)

The presence of hierarchy in many real-world networks is not yet fully understood. We observe that complex interaction networks are often coarse-grain models of vast modular networks, where tightly connected subgraphs are agglomerated into nodes for simplicity of representation and computational feasibility. The emergence of hierarchy in such growing complex networks may stem from one particular property of these ignored subgraphs: their graph conductance. Being a quantification of the main bottleneck of flow through the coarse-grain node, this scalar quantity implies a structural limitation and supports the consideration of heterogeneous degree constraints. The internal conductance values of the subgraphs are …

Network-Based Analysis Of Early Pandemic Mitigation Strategies: Solutions, And Future Directions, Pegah Hozhabrierdi, Raymond Zhu, Maduakolam Onyewu, Sucheta Soundarajan

Northeast Journal of Complex Systems (NEJCS)

Despite the large amount of literature on mitigation strategies for pandemic spread, in practice, we are still limited by naive strategies, such as lockdowns, that are not effective in controlling the spread of the disease in long term. One major reason behind adopting basic strategies in real-world settings is that, in the early stages of a pandemic, we lack knowledge of the behavior of a disease, and so cannot tailor a more sophisticated response. In this study, we design different mitigation strategies for early stages of a pandemic and perform a comprehensive analysis among them. We then propose a novel …

Anticipation Induces Polarized Collective Motion In Attraction Based Models, Daniel Strömbom, Alice Antia

Northeast Journal of Complex Systems (NEJCS)

Moving animal groups are prime examples of natural complex systems. In most models of such systems each individual updates its heading based on the current positions and headings of its neighbors. However, recently, a number of models where the heading update instead is based on the future anticipated positions/headings of the neighbors have been published. Collectively these studies have established that including anticipation may have drastically different effects in different models. In particular, anticipation inhibits polarization in alignment-based models and in one alignment-free model, but promotes polarization in another alignment-free model. Indicating that our understanding of how anticipation affects the …

A Dynamic Energy Budget Model Of Ornate Box Turtle Shell Growth, Tyler Skorczewski, Brandon Andersen

Spora: A Journal of Biomathematics

Many aspects of box turtle development may depend on size rather than age. Notable examples include sexual maturity and the development of the fully closing hinge in the shell that allows box turtles to completely hide in their shells. Thus, it is important to understand how turtles grow in order to have a complete understanding of turtle biology. Previous studies show that turtle shell growth behaves in a logistic manner. These studies use functional models that fit the data well but do little to explain mechanisms. In this work we use the ideas found in dynamic energy budget theory to …

Flattening The Curve: The Effects Of Intervention Strategies During Covid-19, Kelly A. Reagan, Rachel J. Pryor, Gonzalo M. Bearman, David M. Chan

Spora: A Journal of Biomathematics

COVID-19 has plagued countries worldwide due to its infectious nature. Social distancing and the use of personal protective equipment (PPE) are two main strategies employed to prevent its spread. A SIR model with a time-dependent transmission rate is implemented to examine the effect of social distancing and PPE use in hospitals. These strategies’ effect on the size and timing of the peak number of infectious individuals are examined as well as the total number of individuals infected by the epidemic. The effect on the epidemic of when social distancing is relaxed is also examined. Overall, social distancing was shown to …

On Generating Transferable Targeted Perturbations, Muzammal Naseer, Salman Khan, Munawar Hayat, Fahad Shahbaz Khan, Fatih Porikli

Computer Vision Faculty Publications

While the untargeted black-box transferability of adversarial perturbations has been extensively studied before, changing an unseen model's decisions to a specific 'targeted' class remains a challenging feat. In this paper, we propose a new generative approach for highly transferable targeted perturbations (TTP). We note that the existing methods are less suitable for this task due to their reliance on class-boundary information that changes from one model to another, thus reducing transferability. In contrast, our approach matches the perturbed image 'distribution' with that of the target class, leading to high targeted transferability rates. To this end, we propose a new objective …

Hacking 4 Environment: Oceans Ocg 503, Joanna Burkhardt

Library Impact Statements

No abstract provided.

Remotely Controlled Enzyme Behavior Using Localized Thermal Gradients, Sarah Brown

UNO Student Research and Creative Activity Fair

No existing model describes an identified special case of enzyme behavior when directly stimulated with thermal energy via an RF field.

The ability to remotely influence cellular functions and outcomes is a new approach to targeted medicine. Nano-medicine and biotechnology are the future of medical diagnostics and treatment. The ability to remotely influence cellular functions and outcomes is a new approach to targeted medicine. Direct heating of an enzyme vs bulk heating changes the enzyme activity.

I tested how direct transfer of thermal energy changes rates of enzyme reactions. We created samples of enzymes, attached to ferrous (magnetic) nano-particles, and …

Socastee Interview, Participant #03, March 26, 2021, Jennifer Mokos, Jaime Mccauley

Flood Survivor Interviews

A community member of the Rosewood neighborhood in Socastee is interviewed by a CCU student.

Socastee Interview, Participant #01, March 26, 2021, Jennifer Mokos, Jaime Mccauley

Flood Survivor Interviews

A community member of the Rosewood neighborhood in Socastee is interviewed by CCU students.

Origin Of Magnetism In Γ-Fesi 2 /Si(111) Nanostructures, Liwei D. Geng, Sahil Dhoka, Ilan Goldfarb, Ranjit Pati, Yongmei M. Jin

Michigan Tech Publications

Magnetism has recently been observed in nominally nonmagnetic iron disilicide in the form of epitaxial γ-FeSi2 nanostructures on Si(111) substrate. To explore the origin of the magnetism in γ-FeSi2/Si(111) nanostructures, we performed a systematic first-principles study based on density functional theory. Several possible factors, such as epitaxial strain, free surface, interface, and edge, were examined. The calculations show that among these factors, only the edge can lead to the magnetism in γ-FeSi2/Si(111) nanostructures. It is shown that magnetism exhibits a strong dependency on the local atomic structure of the edge. Furthermore, magnetism can be enhanced by creating multiple-step edges. In …

Developing A Discrete Event Simulation Model To Overcome Human Trafficking, Sydney Meier

UNO Student Research and Creative Activity Fair

Human trafficking is a complex issue that affects society and the global economy. This societal problem involves the commercial exchange and exploitation of people through forced labor, domestic servitude, and sex trade. Human trafficking is considered the third most profitable organized crime in the world. By analyzing the flow of monetary gains/resources, information and trafficked people from the perspective of traffickers, police force, and advocacy organizations, this research aims to develop a discrete event simulation model to represent this complex system. The following paper describes the developmental process of acquiring data and creating a base model. While the model is …

Competitive Reductive Removal Of Chromate And Pertechnetate Via Zero-Valent Iron, Jonathan Williams Ramirez

FIU Electronic Theses and Dissertations

Treatment to immobilize radioactive waste is of concern for long-term storage, avoiding future environmental exposure. Most production of Technetium-99 (⁹⁹Tc) occurred as a byproduct of development of legacy nuclear weapons research. Zero-valent iron (ZVI) is a promising reductant of Tc(VII) to a less mobile ⁹⁹Tc(IV). However, more redox-sensitive contaminants can compete in the reductive process. Therefore, it is important to examine the effects of competitive contaminants and quantify the effects on the reductive removal rates of ⁹⁹Tc. Chromate, Cr(VI), is a redox-sensitive contaminant that is expected to be present in legacy waste present in the Hanford …

Development Of A Real-Time Single-Lead Single-Beat Frequency-Independent Myocardial Infarction Detector, Harold Martin

FIU Electronic Theses and Dissertations

The central aim of this research is the development and deployment of a novel multilayer machine learning design with unique application for the diagnosis of myocardial infarctions (MIs) from individual heartbeats of single-lead electrocardiograms (EKGs) irrespective of their sampling frequencies over a given range. To the best of our knowledge, this design is the first to attempt inter-patient myocardial infarction detection from individual heartbeats of single-lead (lead II) electrocardiograms that achieves high accuracy and near real-time diagnosis. The processing time of 300 milliseconds to a diagnosis is just at the time range in between extremely fast heartbeats of around 300 …

Evaluation Of Harvesting Time For Industrial Hemp (Cannabis Sativa L,) Pilot Project Varieties Grown In South Florida, Jordan W. Prats

FIU Electronic Theses and Dissertations

A field study was conducted to observe the natural development of cannabinoids in three daylength sensitive industrial hemp varieties Bubba Kush (BK), Emerald Flower (EF), and Golden Sunset (GS). Plants were configured in a randomized block design with 3 replications. Once 50% of the plants within a variety reached reproductive growth, plants were sampled weekly until senescence and analyzed through a HPLC-UV/DAD. The results from the study indicate that all three varieties of industrial hemp tested in field study reached reproductive growth within the first week of transplanting. This is due to a 12-hour day-length at the time and the …

What If Keys Are Leaked? Towards Practical And Secure Re-Encryption In Deduplication-Based Cloud Storage, Weijing You, Lei Lei, Bo Chen, Limin Liu

Michigan Tech Publications

By only storing a unique copy of duplicate data possessed by different data owners, deduplication can significantly reduce storage cost, and hence is used broadly in public clouds. When combining with confidentiality, deduplication will become problematic as encryption performed by different data owners may differentiate identical data which may then become not deduplicable. The Message-Locked Encryption (MLE) is thus utilized to derive the same encryption key for the identical data, by which the encrypted data are still deduplicable after being encrypted by different data owners. As keys may be leaked over time, re-encrypting outsourced data is of paramount importance to …

Electron Field Emission And Electrochemical Lithiation Properties Of Vertically Aligned Carbon Nanotube Arrays Grown Directly On Metal Substrates, Arun Thapa

FIU Electronic Theses and Dissertations

Carbon nanotubes (CNTs) represent one of the critical inventions that have triggered new science and technology in many fields because of their distinctive mechanical, thermal, electrical, electrochemical, and optical properties. Despite the tremendous potential of CNTs, challenges in synthesizing and processing continue to hinder their applications. This dissertation is devoted to synthesizing vertically aligned CNT arrays on metal substrates via plasma-enhanced chemical vapor deposition and the study of their electron field emission (FE) and electrochemical lithiation properties.

Vertically aligned CNTs (VACNTs) are promising electron field emitters for vacuum micro/nano-electronics. Improved control over the morphology and a successful direct-growth of the …

Light And Truth: Measuring Unseen Harm In Individuals And Communities, Hannah Pfost

Undergraduate Honors Theses

While the fields of physics and international development may seem disparate, the insights gained from studying each one of them can improve understanding of the other. Here, I demonstrate that concept as applied to computational optics and historical memory. Thus, the purpose of this project is threefold: (1) to computationally model light transport through tissue, and use that model to inform choices about a physical system; (2) to determine the types of historical memory recommended in the final reports of truth commissions; and (3) to give evidence for the usefulness of human-centered design in both areas. To model light transport, …

Determination Of Atrazine In Glacier Creek Using Gas Chromatography-Mass Spectrometry, Spencer Witte

UNO Student Research and Creative Activity Fair

Atrazine is a commonly used herbicide in agriculture that has been shown to cause adverse health-effects on biological organisms. Glacier Creek Preserve (GCP), a prairie preserve near Omaha, NE, contains restored prairie and agricultural land uses within a single watershed. Surface water samples were collected at various locations of GCP from May to July to quantify atrazine concentrations. Sample preparation included filtering with a 0.45 micron filter and solid-phase extraction (SPE) with a reversed-phase cartridge. The analyte was eluted off the cartridge with ethyl acetate and analyzed by gas chromatography-mass spectrometry (GC/MS). Quantitation was performed with an internal standard calibration …

Discontinuous Galerkin Method Applied To Navier-Stokes Equations, Ian Deruiter, Mahboub Baccouch

UNO Student Research and Creative Activity Fair

Discontinuous Galerkin (DG) finite element methods are becoming important techniques for the computational solution of many real-world problems describe by differential equations. They combine many attractive features of the finite element and the finite volume methods. These methods have been successfully applied to many important PDEs arising from a wide range of applications. DG methods are highly accurate numerical methods and have considerable advantages over the classical numerical methods available in the literature. DG methods can easily handle meshes with hanging nodes, elements of various types and shapes, and local spaces of different orders. Furthermore, DG methods provide accurate and …

Optimizing Networking Topologies With Shortest Path Algorithms, Jordan Sahs

UNO Student Research and Creative Activity Fair

Communication networks tend to contain redundant devices and mediums of transmission, thus the need to locate, document, and optimize networks is increasingly becoming necessary. However, many people do not know where to start the optimization progress. What is network topology? What is this “Shortest Path Problem”, and how can it be used to better my network? These questions are presented, taught, and answered within this paper. To supplement the reader’s understanding there are thirty-eight figures in the paper that are used to help convey and compartmentalize the learning process needed to grasp the materials presented in the ending sections.

In …