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Domain Decomposition Methods For The Solution Of Multiple Scattering Problems, Michael Pedneault Dec 2018

Domain Decomposition Methods For The Solution Of Multiple Scattering Problems, Michael Pedneault

Dissertations

This presents a Schur complement Domain Decomposition (DD) algorithm for the solution of frequency domain multiple scattering problems. Just as in the classical DD methods,(1) the ensemble of scatterers is enclosed in a domain bounded by an artificial boundary, (2) this domain is subdivided into a collection of nonoverlapping subdomains so that the boundaries of the subdomains do not intersect any of the scatterers, and (3) the solutions of the subproblems are connected via Robin boundary conditions matching on the common interfaces between subdomains. Subdomain Robin-to-Robin maps are used to recast the DD problem as a sparse linear system whose …


Fwer Controlling Procedures In Simultaneous And Selective Inference, Li Yu Dec 2018

Fwer Controlling Procedures In Simultaneous And Selective Inference, Li Yu

Dissertations

With increasing complexity of research objectives in clinical trials, a variety of relatively complex and less intuitive multiple testing procedures (MTPs) have been developed and applied in clinical data analysis. In order to make testing strategies more explicit and intuitive to communicate with non-statisticians, several flexible and powerful graphical approaches have recently been introduced in the literature for developing and visualizing newer MTPs. Nevertheless, some theoretical as well as methodological issues still remain to be fully addressed. This dissertation addresses several important issues arising in graphical approaches and related selective inference problems. It consists of three parts.

In the first …


Model Matematis Predator-Prey Tanaman Padi, Hama Penggerek Batang, Tikus, Dan Wereng Batang Coklat Di Karawang, Tesa Nur Padilah, Betha Nurina Sari, Hannie Hannie Dec 2018

Model Matematis Predator-Prey Tanaman Padi, Hama Penggerek Batang, Tikus, Dan Wereng Batang Coklat Di Karawang, Tesa Nur Padilah, Betha Nurina Sari, Hannie Hannie

PYTHAGORAS : Jurnal Matematika dan Pendidikan Matematika

Karawang merupakan salah satu pusat penanaman padi di Pulau Jawa. Keberhasilan panen dapat terganggu oleh adanya organisme pengganggu tumbuhan (OPT) sehingga dapat mengancam target swasembada beras. Hubungan antara tanaman padi dengan OPT dapat dibentuk menjadi suatu model matematis yaitu model predator-prey. Untuk itu, penelitian ini bertujuan untuk menganalisis model matematis predator-prey tanaman padi dan OPT. Predator (pemangsa) adalah makhluk hidup yang memakan mangsa (prey). Model predator-prey antara tanaman padi dengan OPT yang dibahas adalah model tiga predator yaitu hama penggerek batang, tikus, dan wereng batang coklat dengan prey yaitu padi. Pertumbuhan padi mengikuti …


Optimasi Perencanaan Produksi Bahan Bakar Minyak Dengan Fungsi Kendala Fuzzy Menggunakan Metode Goal Programming, Wiwiet Widyaningsih, Sri Andayani Dec 2018

Optimasi Perencanaan Produksi Bahan Bakar Minyak Dengan Fungsi Kendala Fuzzy Menggunakan Metode Goal Programming, Wiwiet Widyaningsih, Sri Andayani

PYTHAGORAS : Jurnal Matematika dan Pendidikan Matematika

Dalam perencanaan produksi PT. Pertamina (Persero) TBBM Boyolali, perusahaan tersebut hanya mendistribusikan BBM sesuai dengan permintaan SPBU tanpa melakukan perhitungan matematis apakah pendapatan yang diperoleh sudah optimal dengan semua faktor dan kendala yang ada, seperti harga setiap jenis BBM, jam kerja mesin pengisian BBM di New Gantry System (NGS), moda transport mobil tangki, dan tingkat keselamatan mobil tangki. Untuk itu, penelitian ini bertujuan untuk melakukan optimasi perencanaan produksi BBM menggunakan metode goal programming agar perusahaan dapat memperoleh pendapatan yang maksimal dengan memperhatikan faktor-faktor dan kendala yang ada. Metode goal programming merupakan perluasan dari linear programming yang dapat menyelesaikan optimasi dengan …


Nonparametric Collective Spectral Density Estimation With An Application To Clustering The Brain Signals, Mehdi Maadooliat, Ying Sun, Tianbo Chen Dec 2018

Nonparametric Collective Spectral Density Estimation With An Application To Clustering The Brain Signals, Mehdi Maadooliat, Ying Sun, Tianbo Chen

Mathematics, Statistics and Computer Science Faculty Research and Publications

In this paper, we develop a method for the simultaneous estimation of spectral density functions (SDFs) for a collection of stationary time series that share some common features. Due to the similarities among the SDFs, the log‐SDF can be represented using a common set of basis functions. The basis shared by the collection of the log‐SDFs is estimated as a low‐dimensional manifold of a large space spanned by a prespecified rich basis. A collective estimation approach pools information and borrows strength across the SDFs to achieve better estimation efficiency. Moreover, each estimated spectral density has a concise representation using the …


Find, Process, And Share: An Optimal Control In The Vidale-Wolfe Marketing Model, Michael C. Barg Dec 2018

Find, Process, And Share: An Optimal Control In The Vidale-Wolfe Marketing Model, Michael C. Barg

CODEE Journal

The Vidale-Wolfe marketing model is a first-order, linear, non-homogeneous ordinary differential equation (ODE) where the forcing term is proportional to advertising expenditure. With an initial response in sales as the initial condition, the solution of the initial value problem is straightforward for a first undergraduate ODE course. The model serves as an excellent example of many relevant topics for those students whose interests lie in economics, finance, or marketing. Its inclusion in the curriculum is particularly rewarding at an institution without a physics program. The model is not new, but it was novel to us when a group of students …


Lozenge Tilings Of A Halved Hexagon With An Array Of Triangles Removed From The Boundary, Part Ii, Tri Lai Dec 2018

Lozenge Tilings Of A Halved Hexagon With An Array Of Triangles Removed From The Boundary, Part Ii, Tri Lai

Department of Mathematics: Faculty Publications

Proctor's work on staircase plane partitions yields an exact enumeration of lozenge tilings of a halved hexagon on the triangular lattice. Rohatgi later ex- tended this tiling enumeration to a halved hexagon with a triangle cut o from the boundary. In his previous paper, the author proved a common generalization of Proctor's and Rohatgi's results by enumerating lozenge tilings of a halved hexagon in the case an array of an arbitrary number of triangles has been removed from a non-staircase side. In this paper we consider the other case when the array of tri- angles has been removed from the …


Power In Pairs: Assessing The Statistical Value Of Paired Samples In Tests For Differential Expression, John R. Stevens, Jennifer S. Herrick, Roger K. Wolff, Martha L. Slattery Dec 2018

Power In Pairs: Assessing The Statistical Value Of Paired Samples In Tests For Differential Expression, John R. Stevens, Jennifer S. Herrick, Roger K. Wolff, Martha L. Slattery

Mathematics and Statistics Faculty Publications

Background: When genomics researchers design a high-throughput study to test for differential expression, some biological systems and research questions provide opportunities to use paired samples from subjects, and researchers can plan for a certain proportion of subjects to have paired samples. We consider the effect of this paired samples proportion on the statistical power of the study, using characteristics of both count (RNA-Seq) and continuous (microarray) expression data from a colorectal cancer study.

Results: We demonstrate that a higher proportion of subjects with paired samples yields higher statistical power, for various total numbers of samples, and for various strengths of …


Numerical Simulation Of Dropped Cylindrical Objects Into Water In Two Dimensions (2d), Yi Zhen Dec 2018

Numerical Simulation Of Dropped Cylindrical Objects Into Water In Two Dimensions (2d), Yi Zhen

University of New Orleans Theses and Dissertations

The dropped objects are identified as one of the top ten causes of fatalities and serious injuries in the oil and gas industry. It is of importance to understand dynamics of dropped objects under water in order to accurately predict the motion of dropped objects and protect the underwater structures and facilities from being damaged. In this thesis, we study nondimensionalization of dynamic equations of dropped cylindrical objects. Nondimensionalization helps to reduce the number of free parameters, identify the relative size of effects of parameters, and gain a deeper insight of the essential nature of dynamics of dropped cylindrical objects …


Limit Properties Of Order Statistics, А. Madraximov, S. Kukieva Dec 2018

Limit Properties Of Order Statistics, А. Madraximov, S. Kukieva

Scientific journal of the Fergana State University

The paper studies the question of estimating the concentration function for the sums of minima of positive random variables.


Substantiation The Parameters Of The Cotton Cleaners’ Polyhedral Vibrating Fire-Bars, A. Djuraev, R.Kh. Maksudov, Sh. Shukhratov Dec 2018

Substantiation The Parameters Of The Cotton Cleaners’ Polyhedral Vibrating Fire-Bars, A. Djuraev, R.Kh. Maksudov, Sh. Shukhratov

Scientific journal of the Fergana State University

The article describes the principle of operation of the recommended multifaceted grate on elastic supports, as well as the results of the analysis of the grate oscillations, and the parameters are justified. The results of comparative production tests.


Mathematical Models For The Numerical Solution Of Boundary Value Problems Nonstationary Three-Phase Filtering, А. Abdukodirov, G. Аkramova Dec 2018

Mathematical Models For The Numerical Solution Of Boundary Value Problems Nonstationary Three-Phase Filtering, А. Abdukodirov, G. Аkramova

Scientific journal of the Fergana State University

The construction of an explicit / implicit scheme for the numerical solution of regional problems of non-stationary three-phase filtration is considered in the article.


Recommendations For Developing Modern Electronic Educational Resources, S. Abdurakhmonov, I. Bilolov Dec 2018

Recommendations For Developing Modern Electronic Educational Resources, S. Abdurakhmonov, I. Bilolov

Scientific journal of the Fergana State University

The article discusses the use of AutoPlay Media Studio in creating e-learning resources, and also studies the technology of creating electronic resources. Based on the examples, recommendations for use in the education system are developed and provided,


The Way Of Obtaining Of Polyfunctional Haemosorbent, Х. Eshjanov, А. Sarimsakov, М., Baltayeva, М. Nurmatova Dec 2018

The Way Of Obtaining Of Polyfunctional Haemosorbent, Х. Eshjanov, А. Sarimsakov, М., Baltayeva, М. Nurmatova

Scientific journal of the Fergana State University

In the article the facts about separation fibroin fibers from waste matter of silk fibers and the properties of haemosorbent vitamin-B12 sorbtion are given.


Logarithmic Hennings Invariants For Restricted Quantum Sl (2), Anna Beliakova, Christian Blanchet, Alexandra Tebbs Dec 2018

Logarithmic Hennings Invariants For Restricted Quantum Sl (2), Anna Beliakova, Christian Blanchet, Alexandra Tebbs

Mathematics and Statistics Faculty Publications

We construct a Hennings-type logarithmic invariant for restricted quantum sl (2) at a 2pth root of unity. This quantum group U is not quasitriangular and hence not ribbon, but factorizable. The invariant is defined for a pair: a 3–manifold M and a colored link L inside M. The link L is split into two parts colored by central elements and by trace classes, or elements in the 0th Hochschild homology of U, respectively. The two main ingredients of our construction are the universal invariant of a string link with values in tensor powers of U, and the modified …


A New Trend In Human Reproduction - Women In The Usa, Abby Rokke Dec 2018

A New Trend In Human Reproduction - Women In The Usa, Abby Rokke

Essential Studies UNDergraduate Showcase

The control a woman is allowed to have over her own reproductive system has been a recent popular topic of debate. Since the 1950's, women have made up over half of the total United States population. With women making up the majority of the country's citizens, it would be quite the contradiction for them to not have the right to make decisions about their own bodies. Over the last two decades many contraceptive and medical advances have assisted in a woman's ability to make her own choice. An interesting trend in childbearing has occurred from this new wave of technologies. …


Equations Of Motion In A Rotating Noninertial Reference Frame, Nicholas L. Sponsel Dec 2018

Equations Of Motion In A Rotating Noninertial Reference Frame, Nicholas L. Sponsel

Essential Studies UNDergraduate Showcase

Measurement is an essential part of empirical research. As such, understanding whether the frame of reference in which a measurement occurs is inertial is essential for accurate data. As a rotating sphere, Earth is a non-inertial frame of reference and gives rise to fictitious forces. These forces are derived through vector algebra and further solved through matrix differential equations. The final solution for how velocity evolves over time results in sinusoidal functions with a period of 24 hours for Earth. To test the equations further, rational scenarios are proposed for different locations on the surface of Earth involving different initial …


Modeling The Spread Of Disease, James Hollister Dec 2018

Modeling The Spread Of Disease, James Hollister

Essential Studies UNDergraduate Showcase

Mathematically modeling the spread of disease in a population is a focus among epidemiologists. Using an SIR model (susceptible, infected, and recovered), we can create a system of differential equations to help better understand how a disease spreads in a simple environment. However, if we are to create a more realistic environment, computer simulations may be necessary. We can use the results from these simulations to try and find ways to eradicate the disease as efficiently as possible. In this poster, we will present the SIR model, present a system of differential equations that describe the movement of disease in …


Gizmos Computer Simulations In The Mathematics Classroom, Bethany L. Inman Dec 2018

Gizmos Computer Simulations In The Mathematics Classroom, Bethany L. Inman

Morehead State Theses and Dissertations

A capstone submitted in partial fulfillment of the requirements for the degree of Doctor of Education in the College of Education at Morehead State University by Bethany L. Inman on December 6, 2018


Subsets Of Vertices Of The Same Size And The Same Maximum Distance, Maria Axenovich, Dominik Duerrschnabel Dec 2018

Subsets Of Vertices Of The Same Size And The Same Maximum Distance, Maria Axenovich, Dominik Duerrschnabel

Theory and Applications of Graphs

For a simple connected graph G=(V,E) and a subset X of its vertices, let

d*(X) = max {dist}G(x,y): x,y ∈ X}

and let h*(G) be the largest k such that there are disjoint vertex subsets A and B of G, each of size k such that d*(A) = d*(B). Let h*(n) = min {h*(G): |V(G)|=n}. We prove that h*(n) =⌊(n+1)/3 ⌋, for n ≥ 6. This solves the homometric set problem restricted to the largest distance exactly. In addition we compare h*(G) with a respective function hdiam(G), where …


Control Theory: The Double Pendulum Inverted On A Cart, Ian J P Crowe-Wright Dec 2018

Control Theory: The Double Pendulum Inverted On A Cart, Ian J P Crowe-Wright

Mathematics & Statistics ETDs

In this thesis the Double Pendulum Inverted on a Cart (DPIC) system is modeled using the Euler-Lagrange equation for the chosen Lagrangian, giving a second-order nonlinear system. This system can be approximated by a linear first-order system in which linear control theory can be used. The important definitions and theorems of linear control theory are stated and proved to allow them to be utilized on a linear version of the DPIC system. Controllability and eigenvalue placement for the linear system are shown using MATLAB. Linear Optimal control theory is likewise explained in this section and its uses are applied to …


Equilibrium Analysis For An Epidemic Model With A Reservoir For Infection, Istvan Lauko, Gabriella Pinter, Rachel Elizabeth Tewinkel Dec 2018

Equilibrium Analysis For An Epidemic Model With A Reservoir For Infection, Istvan Lauko, Gabriella Pinter, Rachel Elizabeth Tewinkel

Mathematical Sciences Student Articles

We consider a system of non-linear differential equations describing the spread of an epidemic in two interacting populations. The model assumes that the epidemic spreads within the first population, which in turn acts as a reservoir of infection for the second population. Weexplore the conditions under which the epidemic is endemic in both populations and discuss the global asymptotic stability of the endemic equilibrium using a Lyapunov function and results established for asymptotically autonomous systems. We discuss monkeypox as an example of an emerging disease that can be modelled in this way and present some numerical results representing the model …


On Nonnegatively Curved Hypersurfaces In Hyperbolic Space, Vincent Bonini, Shiguang Ma, Jie Qing Dec 2018

On Nonnegatively Curved Hypersurfaces In Hyperbolic Space, Vincent Bonini, Shiguang Ma, Jie Qing

Mathematics

In this paper we prove a conjecture of Alexander and Currier that states, except for covering maps of equidistant surfaces in hyperbolic 3-space, a complete, nonnegatively curved immersed hypersurface in hyperbolic space is necessarily properly embedded.


Invariant Subspaces Of Compact Operators And Related Topics, Weston Mckay Grewe Dec 2018

Invariant Subspaces Of Compact Operators And Related Topics, Weston Mckay Grewe

Mathematics

The invariant subspace problem asks if every bounded linear operator on a Banach space has a nontrivial closed invariant subspace. Per Enflo has shown this is false in general, however it is known that every compact operator has an invariant subspace. The purpose of this project is to explore introductory results in functional analysis. Specifically we are interested in understanding compact operators and the proof that all compact operators on a Hilbert space have an invariant subspace. In the process of doing this we build up many examples and theorems relating to operators on a Hilbert or Banach space. Continuing …


Predicted Deepwater Bathymetry From Satellite Altimetry: Non-Fourier Transform Alternatives, Maxsimo Salazar Dec 2018

Predicted Deepwater Bathymetry From Satellite Altimetry: Non-Fourier Transform Alternatives, Maxsimo Salazar

Dissertations

Robert Parker (1972) demonstrated the effectiveness of Fourier Transforms (FT) to compute gravitational potential anomalies caused by uneven, non-uniform layers of material. This important calculation relates the gravitational potential anomaly to sea-floor topography. As outlined by Sandwell and Smith (1997), a six-step procedure, utilizing the FT, then demonstrated how satellite altimetry measurements of marine geoid height are inverted into seafloor topography. However, FTs are not local in space and produce Gibb’s phenomenon around discontinuities. Seafloor features exhibit spatial locality and features such as seamounts and ridges often have sharp inclines. Initial tests compared the windowed-FT to wavelets in reconstruction of …


Larval Food Limitation In A Speyeria Butterfly (Nymphalidae): How Many Butterflies Can Be Supported?, Ryan I. Hill, Cassidi E. Rush, John Mayberry Dec 2018

Larval Food Limitation In A Speyeria Butterfly (Nymphalidae): How Many Butterflies Can Be Supported?, Ryan I. Hill, Cassidi E. Rush, John Mayberry

College of the Pacific Faculty Articles

For herbivorous insects the importance of larval food plants is obvious, yet the role of host abundance and density in conservation are relatively understudied. Populations of Speyeria butterflies across North America have declined and Speyeria adiaste is an imperiled species endemic to the southern California Coast Ranges. In this paper, we study the link between the food plant Viola purpurea quercetorum and abundance of its herbivore Speyeria adiaste clemencei to better understand the butterfly’s decline and aid in restoration of this and other Speyeria species. To assess the degree to which the larval food plant limits adult abundance of S. …


Another Characterization Of Warped Product Submanifolds Of Nearly Cosymplectic Manifolds, Ali H. Alkhaldi, Abid Kamal Dec 2018

Another Characterization Of Warped Product Submanifolds Of Nearly Cosymplectic Manifolds, Ali H. Alkhaldi, Abid Kamal

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, we study warped product pseudo-slant submanifolds of nearly cosymplectic manifolds. First, we derive the integrability conditions of the distributions and then, we investigate the geometry of the leaves of both distributions. Also, we prove a characterization theorem for a pseudo-slant submanifold to be locally a warped product manifold.


Non-Continuous Double Barrier Reflected Bsdes With Jumps Under A Stochastic Lipschitz Coefficient, Mohamed Marzougue, Mohamed El Otmani Dec 2018

Non-Continuous Double Barrier Reflected Bsdes With Jumps Under A Stochastic Lipschitz Coefficient, Mohamed Marzougue, Mohamed El Otmani

Communications on Stochastic Analysis

No abstract provided.


Functional Central Limit Theorem For Additive Functionals Associated To The Generalized Nelson Hamiltonian, Soumaya Gheryani, Achref Majid, Habib Ouerdiane Dec 2018

Functional Central Limit Theorem For Additive Functionals Associated To The Generalized Nelson Hamiltonian, Soumaya Gheryani, Achref Majid, Habib Ouerdiane

Communications on Stochastic Analysis

No abstract provided.


Generalized Random Fields And Lévy's Continuity Theorem On The Space Of Tempered Distributions, Hermine Biermé, Olivier Durieu, Yizao Wang Dec 2018

Generalized Random Fields And Lévy's Continuity Theorem On The Space Of Tempered Distributions, Hermine Biermé, Olivier Durieu, Yizao Wang

Communications on Stochastic Analysis

No abstract provided.