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Truancy In High School, Itzel Ruiz, Jason Mink, Xochitl Aleman 2018 Northeastern Illinois University

Truancy In High School, Itzel Ruiz, Jason Mink, Xochitl Aleman

SPACE: Student Perspectives About Civic Engagement

The main focus of this project is to analyze students’ poor attendance in order to understand the applicable factors as to why upperclassmen tend to miss more school than students in younger grades. We will be focusing on how students relationships with parents and teachers affect upperclassmen attendance. An anonymous ten question survey was given to five Junior and Senior Civics and U.S. History classes at Steinmetz College Prep high school. The questions were geared towards the students days absent during the school year, and their relationship with teachers and parents. Majority of the students surveyed missed more than 20 …


Modeling Mayfly Nymph Length Distribution And Population Dynamics Across A Gradient Of Stream Temperatures And Stream Types, Jeremy Anthony, Jennifer Baccam, Imanuel Bier, Emily Gregg, Leif Halverson, Ryan Mulcahy, Emmanuel Okanla, Samira A. Osman, Adam R. Pancoast, Kevin C. Schultz, Alex Sushko, Jennifer Vorarath, Yia Vue, Austin Wagner, Emily Gaenzle Schilling, John M. Zobitz 2018 Augsburg College

Modeling Mayfly Nymph Length Distribution And Population Dynamics Across A Gradient Of Stream Temperatures And Stream Types, Jeremy Anthony, Jennifer Baccam, Imanuel Bier, Emily Gregg, Leif Halverson, Ryan Mulcahy, Emmanuel Okanla, Samira A. Osman, Adam R. Pancoast, Kevin C. Schultz, Alex Sushko, Jennifer Vorarath, Yia Vue, Austin Wagner, Emily Gaenzle Schilling, John M. Zobitz

Spora: A Journal of Biomathematics

We analyze a process-based temperature model for the length distribution and population over time of mayfly nymphs. Model parameters are estimated using a Markov Chain Monte Carlo parameter estimation method utilizing length distribution data at five different stream sites. Two different models (a standard exponential model and a modified Weibull model) of mayfly mortality are evaluated, where in both cases mayfly length growth is a function of stream temperature. Based on model-data comparisons to the modeled length distribution and the Bayesian Information Criterion, we found that approaches that length distribution data can reliably estimate 2–3 model parameters. Future model development …


The Entrance Times Of Feigenbaum's Map, Akhtam Dzhalilov, Khamza Kudratov 2018 Turin Polytechnic University, Kichik Halka yuli 17, Tashkent 100095, Uzbekistan.

The Entrance Times Of Feigenbaum's Map, Akhtam Dzhalilov, Khamza Kudratov

Acta of Turin Polytechnic University in Tashkent

It is well known that the Feigenbaum's map ϕ plays main role in theory of universality. The map ϕ is unimodal, even, analitic map of the interval [-1; 1] with one critical point. It is important that the Feigenbaum's map ϕ have infinitely many unstable periodic points and an attractor K of "Cantor type". In present work we investigate the behaviour of entrance times to the set F:


Uniform Distribution For Piecewise-Linear Herman's Maps With Two Breaks, Akhtam Dzhalilov, Khamza Tashkulov 2018 Turin Polytechnic University, Kichik Halka yuli 17, Tashkent 100095, Uzbekistan.

Uniform Distribution For Piecewise-Linear Herman's Maps With Two Breaks, Akhtam Dzhalilov, Khamza Tashkulov

Acta of Turin Polytechnic University in Tashkent

Let h be a piecewise-linear (PL) circle homeomorphism with two break points a0 , c0 and irrational rotation number ρh . Denote by qn , n ≥ 1 the first return times of h and 000(0)():(0)hhaahaσ′−=′+ the jump of h at the point a0 . We prove that for every 1xS∈ the sequence 01log()mod1,1log()nqhDhxnaσ≥ is uniformly distributed on [0,1].


Communication Based Control For Dc Microgrids, Mahmoud S. Saleh, Yusef Esa, Ahmed Mohamed 2018 CUNY City College

Communication Based Control For Dc Microgrids, Mahmoud S. Saleh, Yusef Esa, Ahmed Mohamed

Publications and Research

Centralized communication-based control is one of the main methods that can be implemented to achieve autonomous advanced energy management capabilities in DC microgrids. However, its major limitation is the fact that communication bandwidth and computation resources are limited in practical applications. This can be often improved by avoiding redundant communications and complex computations. In this paper, an autonomous communication-based hybrid state/event driven control scheme is proposed. This control scheme is hierarchical and heuristic, such that on the primary control level, it encompasses state-driven local controllers, and on the secondary control level, an event-driven MG centralized controller (MGCC) is used. This …


Quasi-Symmetric Distribution Function Of Invariant Measure Of Circle Homeomorphisms With Singularities, U.A. Safarov 2018 Turin Polytechnic University, Kichik Halka yuli 17, Tashkent 100095, Uzbekistan.

Quasi-Symmetric Distribution Function Of Invariant Measure Of Circle Homeomorphisms With Singularities, U.A. Safarov

Acta of Turin Polytechnic University in Tashkent

Let f be a circle homeomorphism with single critical point of non-integer order, that is, 1()()||()dcrcrcrfxxxxxfx−=−−+, 2d>, for some δ-neighborhood ()crUxδ. We prove that, if the homeomorphism f is P-homeomorphism on the set 1\()crSUxδ with irrational rotation numberfρ, then f is topologically conjugate to the pure rotation fρ . Moreover, ϕ is quasi-symmetric if and only if fρ is of bounded type.


Modeling Mayfly Nymph Length Distribution And Population Dynamics Across A Gradient Of Stream Temperatures And Stream Types, Jeremy Anthony, Jennifer Baccam, Imanuel Bier, Emily Gregg, Leif Halverson, Ryan Mulcahy, Emmanuel Okanla, Samira A. Osman, Adam R. Pancoast, Kevin C. Schultz, Alex Sushko, Jennifer Vorarath, Yia Vue, Austin Wagner, Emily Gaenzle Schilling, John Zobitz 2018 Augsburg University

Modeling Mayfly Nymph Length Distribution And Population Dynamics Across A Gradient Of Stream Temperatures And Stream Types, Jeremy Anthony, Jennifer Baccam, Imanuel Bier, Emily Gregg, Leif Halverson, Ryan Mulcahy, Emmanuel Okanla, Samira A. Osman, Adam R. Pancoast, Kevin C. Schultz, Alex Sushko, Jennifer Vorarath, Yia Vue, Austin Wagner, Emily Gaenzle Schilling, John Zobitz

Faculty Authored Articles

We analyze a process-based temperature model for the length distribution and population over time of mayfly nymphs. Model parameters are estimated using a Markov Chain Monte Carlo parameter estimation method utilizing length distribution data at five different stream sites. Two different models (a standard exponential model and a modified Weibull model) of mayfly mortality are evaluated, where in both cases mayfly length growth is a function of stream temperature. Based on model-data comparisons to the modeled length distribution and the Bayesian Information Criterion, we found that approaches that length distribution data can reliably estimate 2–3 model parameters. Future model development …


Theoretical Open-Loop Model Of Respiratory Mechanics In The Extremely Preterm Infant, Laura Ellwein Fix, Joseph Khoury, Russell R. Moores Jr., Lauren Linkous, Matthew Brandes, Henry J. Rozycki 2018 Virginia Commonwealth University

Theoretical Open-Loop Model Of Respiratory Mechanics In The Extremely Preterm Infant, Laura Ellwein Fix, Joseph Khoury, Russell R. Moores Jr., Lauren Linkous, Matthew Brandes, Henry J. Rozycki

Mathematics and Applied Mathematics Publications

Non-invasive ventilation is increasingly used for respiratory support in preterm infants, and is associated with a lower risk of chronic lung disease. However, this mode is often not successful in the extremely preterm infant in part due to their markedly increased chest wall compliance that does not provide enough structure against which the forces of inhalation can generate sufficient pressure. To address the continued challenge of studying treatments in this fragile population, we developed a nonlinear lumped-parameter respiratory system mechanics model of the extremely preterm infant that incorporates nonlinear lung and chest wall compliances and lung volume parameters tuned to …


Resistance Temperature Detectors In A Cryostat Refrigeration System, Kirsten Marie Manahan, Alice Callen 2018 San Diego State University

Resistance Temperature Detectors In A Cryostat Refrigeration System, Kirsten Marie Manahan, Alice Callen

STAR Program Research Presentations

The Large Synoptic Survey Telescope (LSST) is a ground-based telescope that will survey the Southern sky every few nights. Located in the telescope will be a 3.2 gigapixel digital camera. To ensure proper instrumentation of the camera, there must be a monitored stable temperature. As part of my research, I assembled resistance temperature detectors and tested them to verify their reliability in measuring temperature in the camera’s cryostat refrigeration cooling system. Resistance temperature detectors function by the principle of thermal resistivity, in which their electrical resistances vary as temperature varies. Through testing, I was able to determine whether these particular …


Examples Of The Birkhoff Theorem And Its Generalizations, Charles G. Torre 2018 Department of Physics, Utah State University

Examples Of The Birkhoff Theorem And Its Generalizations, Charles G. Torre

Tutorials on... in 1 hour or less

In this worksheet I demonstrate three versions of Birkhoff's theorem, which is a characterization of spherically symmetric solutions of the Einstein equations. The three versions considered here correspond to taking the "Einstein equations" to be: (1) the vacuum Einstein equations; (2) the Einstein equations with a cosmological constant (3) the Einstein-Maxwell equations. I will restrict my attention to 4-dimensional spacetimes.


How To Make Tetrads, Charles G. Torre 2018 Department of Physics, Utah State University

How To Make Tetrads, Charles G. Torre

How to... in 10 minutes or less

This is a worksheet which demonstrates tools for creating orthonormal and null tetrads for a given spacetime.


Applied Mathematical Programming, Man-Keun Kim, Bruce A. McCarl, Thomas H. Spreen 2018 Utah State University

Applied Mathematical Programming, Man-Keun Kim, Bruce A. Mccarl, Thomas H. Spreen

Textbooks

This book is intended to both serve as a reference guide and a text for a course on Applied Mathematical Programming for upper undergraduate and Master level students in Economics, Applied Economics, Agricultural and Resource Economics, and Management; primarily based on McCarl and Spreen (2013). The material presented in McCarl and Spreen (2013) concentrates upon conceptual issues, problem formulation, computerized problem solution, and results interpretation; it is designed for the advanced readers who are familiar with mathematical economics including linear and matrix algebra and also with advanced modeling skills. Upper level undergraduate and/or Master students may not be beneficial from …


Sequential Probing With A Random Start, Joshua Miller 2018 Claremont Colleges

Sequential Probing With A Random Start, Joshua Miller

HMC Senior Theses

Processing user requests quickly requires not only fast servers, but also demands methods to quickly locate idle servers to process those requests. Methods of finding idle servers are analogous to open addressing in hash tables, but with the key difference that servers may return to an idle state after having been busy rather than staying busy. Probing sequences for open addressing are well-studied, but algorithms for locating idle servers are less understood. We investigate sequential probing with a random start as a method for finding idle servers, especially in cases of heavy traffic. We present a procedure for finding the …


Recurrent Neural Networks And Their Applications To Rna Secondary Structure Inference, Devin Willmott 2018 University of Kentucky

Recurrent Neural Networks And Their Applications To Rna Secondary Structure Inference, Devin Willmott

Theses and Dissertations--Mathematics

Recurrent neural networks (RNNs) are state of the art sequential machine learning tools, but have difficulty learning sequences with long-range dependencies due to the exponential growth or decay of gradients backpropagated through the RNN. Some methods overcome this problem by modifying the standard RNN architecure to force the recurrent weight matrix W to remain orthogonal throughout training. The first half of this thesis presents a novel orthogonal RNN architecture that enforces orthogonality of W by parametrizing with a skew-symmetric matrix via the Cayley transform. We present rules for backpropagation through the Cayley transform, show how to deal with the Cayley …


Symmetric Criticality In General Relativity, Charles G. Torre 2018 Department of Physics, Utah State University

Symmetric Criticality In General Relativity, Charles G. Torre

Research Vignettes

In this worksheet I explore the local Lagrangian version of the Principle of Symmetric Criticality (PSC) due to Anderson, Fels, and Torre], which asserts the commutativity of the processes (i) of symmetry reduction (for finding group-invariant fields) and (ii) forming Euler-Lagrange equations. There are two obstructions to PSC, which I will call the Lie algebra obstruction and the isotropy obstruction. In this worksheet I will illustrate these obstructions in the General Theory of Relativity.


Modeling The Disappearance Of The Neanderthals Using Concepts Of Population Dynamics And Ecology, Michael F. Roberts, Stephen E. Bricher 2018 Linfield College

Modeling The Disappearance Of The Neanderthals Using Concepts Of Population Dynamics And Ecology, Michael F. Roberts, Stephen E. Bricher

Faculty Publications

Current hypotheses regarding the disappearance of Neanderthals (NEA) in Europe fall into two main categories: climate change, and competition. Here we review current research and existing mathematical models that deal with this question, and we propose an approach that incorporates and permits the investigation of the current hypotheses. We have developed a set of differential equations that model population dynamics of anatomically modern humans (AMH) and NEA, their ecological relations to prey species, and their mutual interactions. The model allows investigators to explore each of the two main categories or combinations of both, as well as various forms of competition …


Random Walks On Simple Two-Dimensional Manifolds, Tom Eichlersmith 2018 Hamline University

Random Walks On Simple Two-Dimensional Manifolds, Tom Eichlersmith

Departmental Honors Projects

A C++ implementation of random walks is constructed with examples for the plane, sphere, and torus included. This package is available publicly, and can be expanded to different situations on the included surfaces as well as other surfaces. The random walks are studied by measuring how long they take to reach a pre-defined escape region on the surface. These escape regions and their interaction with the surface are what affect the behavior of the random walks the most.


Modeling Public Opinion, Arden Baxter 2018 Rollins College

Modeling Public Opinion, Arden Baxter

Honors Program Theses

The population dynamics of public opinion have many similarities to those of epidemics. For example, models of epidemics and public opinion share characteristics like contact rates, incubation times, and recruitment rates. Generally, epidemic dynamics have been presented through epidemiological models. In this paper we adapt an epidemiological model to demonstrate the population dynamics of public opinion given two opposing viewpoints. We find equilibrium solutions for various cases of the system and examine the local stability. Overall, our system provides sociological insight on the spread and transition of a public opinion.


Existing And Regularity Of Minimizers For Nonlocal Energy Functionals, Mikil D. Foss, Petronela Radu, Cory Wright 2018 University of Nebraska-Lincoln

Existing And Regularity Of Minimizers For Nonlocal Energy Functionals, Mikil D. Foss, Petronela Radu, Cory Wright

Department of Mathematics: Faculty Publications

In this paper, we consider minimizers for nonlocal energy functionals generalizing elastic energies that are connected with the theory of peridynamics [19] or nonlocal diffusion models [1]. We derive nonlocal versions of the Euler-Lagrange equations under two sets of growth assumptions for the integrand. Existence of minimizers is shown for integrands with joint convexity (in the function and nonlocal gradient components). By using the convolution structure, we show regularity of solutions for certain Euler-Lagrange equations. No growth assumptions are needed for the existence and regularity of minimizers results, in contrast with the classical theory.


Computing Eigenmodes Of Elliptic Operators On Manifolds Using Radial Basis Functions, Vladimir Delengov 2018 Claremont Colleges

Computing Eigenmodes Of Elliptic Operators On Manifolds Using Radial Basis Functions, Vladimir Delengov

CGU Theses & Dissertations

In this work, a numerical approach based on meshless methods is proposed to obtain eigenmodes of Laplace-Beltrami operator on manifolds, and its performance is compared against existing alternative methods. Radial Basis Function (RBF)-based methods allow one to obtain interpolation and differentiation matrices easily by using scattered data points. We derive expressions for such matrices for the Laplace-Beltrami operator via so-called Reilly’s formulas and use them to solve the respective eigenvalue problem. Numerical studies of proposed methods are performed in order to demonstrate convergence on simple examples of one-dimensional curves and two-dimensional surfaces.


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