Physical Sciences and Mathematics Commons^™

A "Warm" Or "Cold" Early Mars: Evidence From Valley Networks, Xuezhi Cang

Graduate Research Theses & Dissertations

Although Mars is cold and dry today, many lines of evidence suggest that ancient Mars had large amount of water and surface fluvial processes. However, climate modelers have encountered difficulties in modeling such early warm and wet conditions with an above freezing temperature, mainly due to the Martian orbit being further away from the Sun and the faintness of the young Sun. The main purpose of this dissertation is to test the ancient Martian climate hypotheses by investigating the spatial pattern of valley network (VN) properties that can survive post-formational modification (i.e., the robust characteristics) and by analogizing the Earth …

Information Systems: No Boundaries! A Concise Approach To Understanding Information Systems For All Disciplines, Shane M. Schartz

All Open Educational Resources

This book was created to provide a different experience for students beginning their studies in information systems. Instead of being bombarded with information from a business systems perspective, the goal of this book is to provide a baseline of material regarding information systems in all disciplines, not just business systems - hence the name No Boundaries!

Adequately Reflecting The Severity Of Tropical Cyclones Using The New Tropical Cyclone Severity Scale, Nadia Bloemendaal, Hans De Moel, Jantsje M. Mol, Priscilla R.M. Bosma, Amy Polen, Jennifer M. Collins

School of Geosciences Faculty and Staff Publications

For decades, meteorologists and governments have been warning communities in coastal areas for an imminent tropical cyclone (TC) using the Saffir-Simpson Hurricane Wind Scale (SSHWS). The SSHWS categorizes a TC based on its maximum wind speed, and is used in defining evacuation strategies and humanitarian response. However, the SSHWS considers only the wind hazard of a TC, whereas a TC can also cause severe conditions through its high storm surges and extreme rainfall, triggering coastal and inland flooding. Consequently, the SSHWS fails to mirror the TC's total severity. This becomes evident when looking at past events such as Hurricane Harvey …

Formation Mechanisms Of Macroscopic Globules In Andesitic Glasses From The Izu–Bonin–Mariana Forearc (Iodp Expedition 352), Raúl O.C. Fonseca, Lina T. Michely, Maria Kirchenbaur, Julie Prytulak, Jeffrey Ryan, Kerstin Hauke, Felipe P. Leitzke, Renat R. Almeev, Chris S. Marien, Axel Gerdes, Rico Schellhorn

School of Geosciences Faculty and Staff Publications

The Izu–Bonin–Mariana volcanic arc is situated at a convergent plate margin where subduction initiation triggered the formation of MORB-like forearc basalts as a result of decompression melting and near-trench spreading. International Ocean Discovery Program (IODP) Expedition 352 recovered samples within the forearc basalt stratigraphy that contained unusual macroscopic globular textures hosted in andesitic glass (Unit 6, Hole 1440B). It is unclear how these andesites, which are unique in a stratigraphic sequence dominated by forearc basalts, and the globular textures therein may have formed. Here, we present detailed textural evidence, major and trace element analysis, as well as B and Sr …

Magma Source Evolution Following Subduction Initiation: Evidence From The Element Concentrations, Stable Isotope Ratios, And Water Contents Of Volcanic Glasses From The Bonin Forearc (Iodp Expedition 352), Daniel A. Coulthard, Mark K. Reagan, Kenji Shimizu, Ilya N. Bindeman, Maryjo Brounce, Renat R. Almeev, Jeffrey Ryan, Timothy Chapman, John Shervais, Julian A. Pearce

School of Geosciences Faculty and Staff Publications

International Ocean Discovery Program Expedition 352 to the Bonin forearc drilled the sequence of volcanic rocks erupted in the immediate aftermath of subduction initiation along the western margin of the Pacific Plate. Pristine volcanic glasses collected during this expedition were analyzed for major and trace elements, halogens, sulfur, and H and O isotopes with goals of characterizing the fluids and melts of subducted materials that were involved in generating the nascent upper plate crust. Incompatible trace element compositions of the oldest lavas (forearc basalts [FAB]) are similar to those of the most depleted mid‐ocean ridge basalts globally. Most FAB were …

Linking Landscape Attributes To Salmon And Decision-Making In The Southern Kenai Lowlands, Alaska, Usa, Coowe M. Walker, Dennis F. Whigham, I. Syverine Bentz, Jacob M. Argueta, Ryan S. King, Mark C. Rains, Charles A. Simenstad, Chris Guo, Steven J. Baird, Conrad J. Field

School of Geosciences Faculty and Staff Publications

While Pacific salmon are economically and culturally important worldwide, Alaska, USA is one of the few remaining places on earth where sustainable management of salmon is possible, even in the face of wide-ranging threats, including overharvesting and the impacts of climate change. A continuing challenge that we face is to understand the ecological processes that result in sustainable salmon populations and report that science to stakeholders in a way that promotes decision-making to avoid the destruction of salmon populations that has occurred in most areas of the lower 48 states. To address this challenge, our studies in the southern Kenai …

Impulsive Volcanic Plumes Generate Volcanic Lightning And Vent Discharges: A Statistical Analysis Of Sakurajima Volcano In 2015, Cassandra M. Smith, Damien Gaudin, Alexa R. Van Eaton, Sonja A. Behnke, Steven Reader, Ronald J. Thomas, Harald Edens, Stephen R. Mcnutt, Corrado Cimarelli

School of Geosciences Faculty and Staff Publications

The origin of electrical activity accompanying volcanic ash plumes is an area of heightened interest in volcanology. However, it is unclear how intense an eruption needs to be to produce lightning flashes as opposed to “vent discharges,” which represent the smallest scale of electrical activity. This study targets 97 carefully monitored plumesJapan, from June 1 to 7, 2015. We use multiparametric measurements from sensors including a nine-station lightning mapping array and an infrared camera to characterize plume ascent. Findings demonstrate that the impulsive, high velocity plumes (>55 m/s) were most likely to create vent discharges, whereas lightning flashes occurred …

Modeling Human Visual Detection Using Deep Networks, Zach Dekraker

Dissertations, Master's Theses and Master's Reports

The work in this report describes the use of machine learning to model human visual detection. This is in contrast to typical machine learning models, which seek to optimize detection performance overall, e.g., precision versus recall or F1 scores. Instead the goal is to develop models that can accurately match humans' abilities to detect objects in images. There are many AI algorithms that have far surpassed humans in, for example, object detection in large image databases or games such as Go. What is different about this work is that the objective is to accurately model humans' performance in visual detection …

Environmental Controls On The Spatial Distribution Of Greenfin Darters And Biodiversity In The Blue Ridge Mountains, Dri Tattersfield

CMC Senior Theses

Disproportionate concentrations of biodiversity in mountains worldwide suggest linkages between geologic processes and biodiversity that are not yet well understood. The Tennessee River Basin in the Blue Ridge Mountains of the southeastern U.S. is a global hotspot for freshwater fish biodiversity. To investigate drivers of biodiversity in the Tennessee River Basin, and explore links to geologic processes, I study the Greenfin Darter (Nothonotus chlorobranchius), a small fish endemic to the upper Tennessee River Basin. I use generalized linear models (GLMs) to evaluate the influence of topography, lithology, climate and land use on the distribution of the Greenfin Darter, …

Exploring Prospective 1-8 Teachers' Number And Operation Sense In The Context Of Fractions, Marta T. Magiera, Leigh A. Van Den Kieboom

Mathematical and Statistical Science Faculty Research and Publications

This exploratory study examined prospective elementary teachers’ (PSTs’) number and operation sense (NOS) in the context of solving problems with fractions. Drawing on the existing literature, we identified seven skills that characterize fraction-related NOS. We analyzed 230 responses to 23 tasks completed by 10 PSTs for evidence of PSTs’ use of different fraction-related NOS skills. The analysis revealed that PSTs did not use all seven fraction-related NOS skills to the same extent. PSTs’ responses documented their frequent reasoning about the meaning of symbols and formal mathematical language in the context of fractions. To a lesser extent, PSTs’ responses documented their …

Multimodal Neuroscience Data Modeling And Inference, Sima Azizi

Doctoral Dissertations

“Mathematical models can be combined with deep learning and machine learning methods to provide new insights in neuroscience. The field of neuroscience is characterized by rich datasets that include fluid biomarkers, EEG signals, and advanced neuroimages. Recent advances in natural language processing have led to the opportunity to gain additional insights from rapidly growing text databases as well as electronic health records. In this research, we focus on applying computational intelligence methods to the analysis of three different complex data sources: blood levels of disease biomarkers, EEG signals from schizophrenic patients, and disease phenotypes encoded in electronic health records. First, …

Complete Experiments On Multi-Photon Ionizations Of Ultra-Cold And Polarized Atoms, Bishnu Prasad Acharya

Doctoral Dissertations

“Fundamental atomic processes such as collision-induced ionization are of relevance in many scientific fields. Describing these reactions can still pose a substantial challenge due to the well-known “few-body problem”, which entails that there is no analytical solution of the equations of motion for systems of more the 2 mutually interacting particle. Novel experimental tools and advancements in theorical methods enable to obtain detailed information on atomic dynamics providing insight into both, the phase as well as the amplitude of the quantum-mechanical wave functions of the particles. In this project, we developed experimental techniques studying multi-photon ionization of lithium in femto-second …

Critical Behavior In Evolutionary And Population Dynamics, Stephen Walter Ordway

Doctoral Dissertations

“This study is an exploration of phase transition behavior in evolutionary and population dynamics, and techniques for predicting population changes, across the disciplines of physics, biology, and computer science. Under the looming threat of climate change, it is imperative to understand the dynamics of populations under environmental stress and to identify early warning signals of population decline. These issues are explored here in (1) a computational model of evolutionary dynamics, (2) an experimental system of decaying populations under environmental stress, and (3) a machine learning approach to predict population changes based on environmental factors. Through the lens of critical phase …

Secure Data Sharing In Cloud And Iot By Leveraging Attribute-Based Encryption And Blockchain, Md Azharul Islam

Doctoral Dissertations

“Data sharing is very important to enable different types of cloud and IoT-based services. For example, organizations migrate their data to the cloud and share it with employees and customers in order to enjoy better fault-tolerance, high-availability, and scalability offered by the cloud. Wearable devices such as smart watch share user’s activity, location, and health data (e.g., heart rate, ECG) with the service provider for smart analytic. However, data can be sensitive, and the cloud and IoT service providers cannot be fully trusted with maintaining the security, privacy, and confidentiality of the data. Hence, new schemes and protocols are required …

Computational Intelligent Impact Force Modeling And Monitoring In Hislo Conditions For Maximizing Surface Mining Efficiency, Safety, And Health, Danish Ali

Doctoral Dissertations

"Shovel-truck systems are the most widely employed excavation and material handling systems for surface mining operations. During this process, a high-impact shovel loading operation (HISLO) produces large forces that cause extreme whole body vibrations (WBV) that can severely affect the safety and health of haul truck operators. Previously developed solutions have failed to produce satisfactory results as the vibrations at the truck operator seat still exceed the “Extremely Uncomfortable Limits”. This study was a novel effort in developing deep learning-based solution to the HISLO problem.

This research study developed a rigorous mathematical model and a 3D virtual simulation model to …

Novel Synthetic Methods And Applications Of Porous Materials: Aerogel Foams, Metallic Aerogels, Amorphous And Graphitic Carbon Aerogels, Rushi Soni

Doctoral Dissertations

"We report novel methods for the synthesis of porous materials such as polymeric aerogel foams, pure metallic aerogels, amorphous and graphitic carbon aerogels, and their applications. I. Polyurethane based aerogel foams were synthesized with an aliphatic triisocyanate and ethylene glycol through a pressurized (7 bar) sol-gel method. The foam-like structure is prepared without any chemical foaming agents or templates, resulting in less expensive, more efficient, readily adaptable, and environmentally friendly process. Those materials exhibited lower thermal conductivity (by 25%) and higher oil adsorption capacity (by 36% w/w) than their corresponding aerogels. II. Monolithic, pure metallic Co(0) aerogels were synthesized from …

Number Fields And Divisible Groups Via Model Theor, Şermi̇n Çam Çeli̇k, Haydar Göral

Turkish Journal of Mathematics

In this note, we first show that solutions of certain equations classify the number fields lying in imaginary quadratic number fields. Then, we study divisible groups with a predicate. We show that these structures are not simple and have the independence property under some natural assumptions.

Traces And Inverse Nodal Problems For A Class Of Delay Sturm-Liouville Operators, Erdoğan Şen

Turkish Journal of Mathematics

In this study, we investigate the regularized sums of eigenvalues, oscillation of eigenfunctions and solutions of inverse nodal problems of discontinuous Sturm-Liouville operators with a delayed argument and with a finite number of transmission conditions. With this aim, we obtain asymptotic formulas for eigenvalues, eigenfunctions and nodal points of the problem. Moreover, some numerical examples are given to illustrate the results. The problem differs from the other discontinuous Sturm-Liouville problems with retarded argument in that it contains a spectral parameter in boundary conditions. If we take the delayed argument $\Delta\equiv0$, the coefficients $\alpha _{i}^{+}=\beta _{i}^{+}=0$ ($i=1,2$) in boundary conditions and …

An Improved Oscillation Criteria For First Order Dynamic Equations, Özkan Öcalan

Turkish Journal of Mathematics

In this work, we consider the first-order dynamic equations \begin{equation*} x^{\Delta }(t)+p(t)x\left( \tau (t)\right) =0,\text{ }t\in \lbrack t_{0},\infty )_{\mathbb{T}} \end{equation*} where $p\in C_{rd}\left( [t_{0},\infty )_{\mathbb{T}},\mathbb{R}^{+}\right) , $ $\tau \in C_{rd}\left( [t_{0},\infty )_{\mathbb{T}},\mathbb{T}\right) $ and $\tau (t)\leq t,\ \lim_{t\rightarrow \infty }\tau (t)=\infty $. When the delay term $\tau (t)$ is not necessarily monotone, we present a new sufficient condition for the oscillation of first-order delay dynamic equations on time scales.

Infinitesimal Bending Of Dna Helices, Miroslav Maksimovic, Ljubica Velimirovic, Marija Najdanovic

Turkish Journal of Mathematics

The mathematics of DNA molecules is often studied as a double helix model. This paper focuses on the modelling of infinitesimal bending of DNA helices. The paper checks the flexibility of DNA molecule, i.e. the flexibility of double helix in infinitesimal bending theory. Actually, first, we find infinitesimal bending field of an arbitrary curve on the helicoid, that leaves bent curves on the helicoid, and show that helix bending on the helicoid is not possible. Finally, we deal with the infinitesimal bending of helicoid, using PDEs. Visualization of infinitesimal bending was done in Mathematica.

A Study Of Impulsive Discrete Dirac System With Hyperbolic Eigenparameter, Turhan Köprübaşi

Turkish Journal of Mathematics

Let $L$ denote the discrete Dirac operator generated in $\ell _{2}\left( %TCIMACRO{\U{2115} }% %BeginExpansion \mathbb{N} %EndExpansion ,% %TCIMACRO{\U{2102} }% %BeginExpansion \mathbb{C} %EndExpansion ^{2}\right) $ by the difference operators of first order% \begin{equation*} \left\{ \begin{array}{cc} {\bigtriangleup y_{n}^{\left( 2\right) }+p_{n}y_{n}^{\left( 1\right) }=\lambda y_{n}^{(1)}} & \\ {\bigtriangleup y_{n-1}^{\left( 1\right) }+q_{n}y_{n}^{\left( 2\right) }=\lambda y_{n}^{(2)}}, \end{array} \text{ }n\in \mathbb{N} \setminus \left\{ k-1,k,k+1\right\} \right. \end{equation*} with boundary and impulsive conditions% \begin{equation*} \begin{array}{c} y_{0}^{(1)}=0\text{ }, \\ \\ \left( \begin{array}{c} y_{k+1}^{(1)} \\ y_{k+2}^{(2)}% \end{array}% \right) =\theta \left( \begin{array}{c} y_{k-1}^{(2)} \\ y_{k-2}^{(1)}% \end{array}% \right) ;\text{ }\theta =\left( \begin{array}{cc} \theta _{1} & \theta _{2} \\ \theta _{3} & \theta _{4}% …

Conformal Generic Submersions, Mehmet Aki̇f Akyol

Turkish Journal of Mathematics

Akyol and Şahin (2017) introduced the notion of conformal semiinvariant submersions from almost Hermitian manifolds. The present paper deals with the study of conformal generic submersions from almost Hermitian manifolds which extends semiinvariant Riemannian submersions, generic Riemannian submersions and conformal semiinvariant submersions in a natural way. We mention some examples of such maps and obtain characterizations and investigate some properties, including the integrability of distributions, the geometry of foliations and totally geodesic foliations. Moreover, we obtain some conditions for such submersions to be totally geodesic and harmonic, respectively.

Exact And Nonstandard Finite Difference Schemes For The Burgers Equation B(2,2), Canan Köroğlu, Ayhan Aydin

Turkish Journal of Mathematics

In this paper, we consider the Burgers equation B(2,2). Exact and nonstandard finite difference schemes (NSFD) for the Burgers equation B(2,2) are designed. First, two exact finite difference schemes for the Burgers equation B(2,2) are proposed using traveling wave solution. Then, two NSFD schemes are represented for this equation. These two NSFD schemes are compared with a standard finite difference (SFD) scheme. Numerical results show that the NSFD schemes are accurate and efficient in the numerical simulation of the kink-wave solution of the B(2,2) equation. We see that although the SFD scheme yields numerical instability for large step sizes, NSFD …

The Lebesgue Constants On Projective Spaces, Alexander Kushpel

Turkish Journal of Mathematics

We give the solution of a classical problem of Approximation Theory on sharp asymptotic of the Lebesgue constants or norms of the Fourier-Laplace projections on the real projective spaces $\mathrm{P}^{d}(\mathbb{R})$. In particular, these results extend sharp asymptotic found by Fejer [2] in the case of $\mathbb{S}^{1}$ in 1910 and by Gronwall [4] in 1914 in the case of $\mathbb{S}^{2}$. The case of spheres, $\mathbb{S}^{d}$, complex and quaternionic projective spaces, $\mathrm{P}^{d}(\mathbb{C})$, $% \mathrm{P}^{d}(\mathbb{H})$ and the Cayley elliptic plane $\mathrm{P}^{16}(% \mathrm{Cay})$ was considered by Kushpel [8].

New Oscillation Criteria For Differential Equations With Sublinear And Superlinear Neutral Terms, Ali Muhib, Elmetwally M. Elabbasy, Osama Moaaz

Turkish Journal of Mathematics

The aim of this article is to establish some new oscillation criteria for the differential equation of even-order of the form \begin{equation*} (r\left( l\right) (y^{\left( n-1\right) }\left( l\right) )^{\alpha })^{\prime }+f(l,x(\tau (l)))=0, \end{equation*} where $y\left( l\right) =x\left( l\right) +p\left( l\right) x^{\beta }\left( \sigma _{1}\left( l\right) \right) +h\left( l\right) x^{\delta }\left( \sigma _{2}\left( l\right) \right) $. By using Riccati transformations, we present new conditions for oscillation of the studied equation. Furthermore, two illustrative examples showing applicability of the new results are included.

Some Soft Topological Properties And Fixed Soft Element Results In Soft Complex Valued Metric Spaces, İzzetti̇n Demi̇r

Turkish Journal of Mathematics

In this paper, first, by using the idea of soft complex numbers as in Das and Samanta [8], we introduce the notion of soft complex valued metric spaces and investigate some of their topological aspects. Next, we establish some fixed soft element theorems for various soft mappings on soft complex valued metric spaces, which are the main results of our paper.

On The Spectral And Scattering Properties Of Eigenparameter Dependent Discrete Impulsive Sturm-Liouville Equations, Yelda Aygar Küçükevci̇li̇oğlu, Elgi̇z Bayram, Güher Gülçehre Özbey

Turkish Journal of Mathematics

This work develops scattering and spectral analysis of a discrete impulsive Sturm-Liouville equation with spectral parameter in boundary condition. Giving the Jost solution and scattering solutions of this problem, we find scattering function of the problem. Discussing the properties of scattering function, scattering solutions, and asymptotic behavior of the Jost solution, we find the Green function, resolvent operator, continuous and point spectrum of the problem. Finally, we give an example in which the main results are made explicit.

Solving Fractional Differential Equations Using Collocation Method Based On Hybrid Of Block-Pulse Functions And Taylor Polynomials, Yao Lu, Yinggan Tang

Turkish Journal of Mathematics

In this paper, a novel approach is proposed to solve fractional differential equations (FDEs) based on hybrid functions. The hybrid functions consist of block-pulse functions and Taylor polynomials. The exact formula for the Riemann--Liouville fractional integral of the hybrid functions is derived via Laplace transform. The FDE under consideration is converted into an algebraic equation with undetermined coefficients by using this formula. A set of linear or nonlinear equations are obtained through collocating the algebraic equation at Newton-Cotes nodes. The numerical solution of the FDE is achieved by solving the linear or nonlinear equations. Error analysis is performed on the …

On Ordered $\Gamma$-Hypersemigroups And Their Relation To Lattice Ordered Semigroups, Niovi Kehayopulu

Turkish Journal of Mathematics

The concept of $\Gamma$-hypersemigroup has been introduced in Turk J Math 2020; 44 (5): 1835-1851 in which it has in which it has been shown that various results on $\Gamma$-hypersemigroups can be obtained directly as corollaries of more general results from the theory of $le$-semigroups (i.e. lattice ordered semigroups having a greatest element) or $poe$-semigroups. As a continuation of the paper mentioned above, in the present paper, the concept of ordered $\Gamma$-hypersemigroups has been introduced, and their relation to lattice ordered semigroups is given. It has been shown that although the results on ordered $\Gamma$-hypersemigroups cannot be obtained as corollaries …

General Rotational $\Xi -$Surfaces In Euclidean Spaces, Kadri̇ Arslan, Yilmaz Aydin, Betül Bulca

Turkish Journal of Mathematics

The general rotational surfaces in the Euclidean 4-space $\mathbb{R}^{4}$ was first studied by Moore (1919). The Vranceanu surfaces are the special examples of these kind of surfaces. Self-shrinker flows arise as special solution of the mean curvature flow that preserves the shape of the evolving submanifold. In addition, $\xi -$surfaces are the generalization of self-shrinker surfaces. In the present article we consider $\xi -$surfaces in Euclidean spaces. We obtained some results related with rotational surfaces in Euclidean $4-$space $\mathbb{R}^{4}$ to become self-shrinkers. Furthermore, we classify the general rotational $\xi -$surfaces with constant mean curvature. As an application, we give some …