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2020

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Essays On Environmental And Health Economics., Prachi Singh Dr. Oct 2020

Essays On Environmental And Health Economics., Prachi Singh Dr.

Doctoral Theses

This thesis consists of three empirical essays that investigate issues in environmental and health economics. The main focus of this thesis is to study how environmental degradation or interventions in this domain can affect demographic and health outcomes of the population in developing countries. The first chapter explores the effect of an information campaign about arsenic contamination in Bangladesh on marriage market outcomes. This study finds that providing information about negative effects of arsenic consumption had an unintended consequence in the marriage market. Specifically, information about lower fertility, skin lesions, cancers and higher mortality related to arsenic exposure induced individuals …


Provable Security Of Symmetric-Key Cryptographic Schemes., Ashwin Jha Dr. Oct 2020

Provable Security Of Symmetric-Key Cryptographic Schemes., Ashwin Jha Dr.

Doctoral Theses

In this thesis, we provide quantitative and/or qualitative improvements in the provable security of several symmetric-key schemes, encompassing major information security goals, viz. data authentication, encryption, and authenticated encryption.AUTHENTICATION AND INTEGRITY: Among authentication schemes, we analyze the CBC-MAC family and counter-based MACs (XMACC, XMACR, PCS, LightMAC etc.), referred as the XMAC family. First, we revisit the security proofs for CBC-MAC and EMAC, and identify a critical flaw in the state-of-the-art results. We revise the security proofs and obtain significantly better bounds in case of EMAC, ECBC and FCBC. Second, we study the security of CBC-MAC family, when the underlying primitive …


Guide To Geometry, Maddison Webb Oct 2020

Guide To Geometry, Maddison Webb

Electronic Theses & Dissertations

Euclid’s Postulates--Polygons--Fundamentals of Euclidean Geometry--Similar Figures--Trigonometry--Tessellations--Non-Euclidean Geometry.


Intrinsic Curvature For Schemes, Pat Lank Oct 2020

Intrinsic Curvature For Schemes, Pat Lank

Mathematics & Statistics ETDs

This thesis develops an algebraic analog of psuedo-Riemannian geometry for relative schemes whose cotangent sheaf is finite locally free. It is a generalization of the algebraic differential calculus proposed by Dr. Ernst Kunz in an unpublished manuscript to the non-affine case. These analogs include the psuedo-Riemannian metric, Levi-Civit´a connection, curvature, and various existence theorems.


Variable-Order Fractional Partial Differential Equations: Analysis, Approximation And Inverse Problem, Xiangcheng Zheng Oct 2020

Variable-Order Fractional Partial Differential Equations: Analysis, Approximation And Inverse Problem, Xiangcheng Zheng

Theses and Dissertations

Variable-order fractional partial differential equations provide a competitive means in modeling challenging phenomena such as the anomalous diffusion and the memory effects and thus attract widely attentions. However, variable-order fractional models exhibit salient features compared with their constant-order counterparts and introduce mathematical and numerical difficulties that are not common in the context of integer-order and constant-order fractional partial differential equations.

This dissertation intends to carry out a comprehensive investigation on the mathematical analysis and numerical approximations to variable-order fractional derivative problems, including variable-order time-fractional, space-fractional, and space-time fractional partial differential equations, as well as the corresponding inverse problems. Novel techniques …


Some Topics Involving Derived Categories Over Noetherian Formal Schemes., Saurabh Singh Dr. Sep 2020

Some Topics Involving Derived Categories Over Noetherian Formal Schemes., Saurabh Singh Dr.

Doctoral Theses

There are two parts to this thesis and both the parts involve working with derived categories over noetherian formal schemes. Beyond this there is no overlap between them and we discuss them separately.The first part concerns Grothendieck duality on noetherian formal schemes.Grothendieck duality is a vast generalisation of Serreduality in algebraic geometry. The main statements in this theory are expressed in the language of derived categories. We begin with an important special case.Let f : X → Y be a proper map of noetherian schemes which is smooth of relative dimension n. For any G ∈ D+ qc(Y ) (where …


Alternative Cichoń Diagrams And Forcing Axioms Compatible With Ch, Corey B. Switzer Sep 2020

Alternative Cichoń Diagrams And Forcing Axioms Compatible With Ch, Corey B. Switzer

Dissertations, Theses, and Capstone Projects

This dissertation surveys several topics in the general areas of iterated forcing, infinite combinatorics and set theory of the reals. There are two parts. In the first half I consider alternative versions of the Cichoń diagram. First I show that for a wide variety of reduction concepts there is a Cichoń diagram for effective cardinal characteristics relativized to that reduction. As an application I investigate in detail the Cichoń diagram for degrees of constructibility relative to a fixed inner model of ZFC. Then I study generalizations of cardinal characteristics to the space of functions from Baire space to Baire space. …


Spectral Sequences For Almost Complex Manifolds, Qian Chen Sep 2020

Spectral Sequences For Almost Complex Manifolds, Qian Chen

Dissertations, Theses, and Capstone Projects

In recent work, two new cohomologies were introduced for almost complex manifolds: the so-called J-cohomology and N-cohomology [CKT17]. For the case of integrable (complex) structures, the former cohomology was already considered in [DGMS75], and the latter agrees with de Rham cohomology. In this dissertation, using ideas from [CW18], we introduce spectral sequences for these two cohomologies, showing the two cohomologies have natural bigradings. We show the spectral sequence for the J-cohomology converges at the second page whenever the almost complex structure is integrable, and explain how both fit in a natural diagram involving Bott-Chern cohomology and the Frolicher spectral sequence. …


Tile Based Self-Assembly Of The Rook's Graph, Ernesto Gonzalez Sep 2020

Tile Based Self-Assembly Of The Rook's Graph, Ernesto Gonzalez

Electronic Theses, Projects, and Dissertations

The properties of DNA make it a useful tool for designing self-assembling nanostructures. Branched junction molecules provide the molecular building blocks for creating target complexes. We model the underlying structure of a DNA complex with a graph and we use tools from linear algebra to optimize the self-assembling process. Some standard classes of graphs have been studied in the context of DNA self-assembly, but there are many open questions about other families of graphs. In this work, we study the rook's graph and its related design strategies.


Growth Of Conjugacy Classes Of Reciprocal Words In Triangle Groups, Blanca T. Marmolejo Sep 2020

Growth Of Conjugacy Classes Of Reciprocal Words In Triangle Groups, Blanca T. Marmolejo

Dissertations, Theses, and Capstone Projects

In this thesis we obtain the growth rates for conjugacy classes of reciprocal words for triangle groups of the form G = Z2 ∗ H where H is finitely generated and does not contain an order 2 element. We explore cases where H is infinite cyclic and finite cyclic. The quotient O = H/G is an orbifold and contains a cone point of order 2, due to the first factor Z2 in the free product G. The reciprocal words in G correspond to geodesics on O which pass through the order 2 cone point on O. We use methods from …


Role Of Influence In Complex Networks, Nur Dean Sep 2020

Role Of Influence In Complex Networks, Nur Dean

Dissertations, Theses, and Capstone Projects

Game theory is a wide ranging research area; that has attracted researchers from various fields. Scientists have been using game theory to understand the evolution of cooperation in complex networks. However, there is limited research that considers the structure and connectivity patterns in networks, which create heterogeneity among nodes. For example, due to the complex ways most networks are formed, it is common to have some highly “social” nodes, while others are highly isolated. This heterogeneity is measured through metrics referred to as “centrality” of nodes. Thus, the more “social” nodes tend to also have higher centrality.

In this thesis, …


Efficient Time-Stepping Approaches For The Dispersive Shallow Water Equations, Linwan Feng Aug 2020

Efficient Time-Stepping Approaches For The Dispersive Shallow Water Equations, Linwan Feng

Dissertations

This dissertation focuses on developing efficient and stable (high order) time-stepping strategies for the dispersive shallow water equations (DSWE) with variable bathymetry. The DSWE extends the regular shallow water equations to include dispersive effects. Dispersion is physically important and can maintain the shape of a wave that would otherwise form a shock in the shallow water system.

In some cases, the DSWE may be simplified when the bathymetry length scales are small (or large) in relation to other length scales in the shallow water system. These simplified DSWE models, which are related to the full DSWEs, are also considered in …


Hybrid Deep Neural Networks For Mining Heterogeneous Data, Xiurui Hou Aug 2020

Hybrid Deep Neural Networks For Mining Heterogeneous Data, Xiurui Hou

Dissertations

In the era of big data, the rapidly growing flood of data represents an immense opportunity. New computational methods are desired to fully leverage the potential that exists within massive structured and unstructured data. However, decision-makers are often confronted with multiple diverse heterogeneous data sources. The heterogeneity includes different data types, different granularities, and different dimensions, posing a fundamental challenge in many applications. This dissertation focuses on designing hybrid deep neural networks for modeling various kinds of data heterogeneity.

The first part of this dissertation concerns modeling diverse data types, the first kind of data heterogeneity. Specifically, image data and …


Resonant Triad Interactions In One And Two-Layer Systems, Malik Chabane Aug 2020

Resonant Triad Interactions In One And Two-Layer Systems, Malik Chabane

Dissertations

This dissertation is a study of the weakly nonlinear resonant interactions of a triad of gravity-capillary waves in systems of one and two fluid layers of arbitrary depth, in one and two-dimentions. For one-layer systems, resonant triad interactions of gravity-capillary waves are considered and a region where resonant triads can be always found is identified, in the two-dimensional wavevector angles-space. Then a description of the variations of resonant wavenumbers and wave frequencies over the resonance region is given. The amplitude equations correct to second order in wave slope are used to investigate special resonant triads that, providing their initial amplitude …


A Generic Implementation Of Fast Fourier Transforms For The Bpas Library, Colin S. Costello Aug 2020

A Generic Implementation Of Fast Fourier Transforms For The Bpas Library, Colin S. Costello

Electronic Thesis and Dissertation Repository

In this thesis we seek to realize an efficient implementation of a generic parallel fast Fourier transform (FFT). The FFT will be used in support of fast multiplication of polynomials with coefficients in a finite field. Our goal is to obtain a relatively high performing parallel implementation that will run over a variety of finite fields with different sized characteristic primes. To this end, we implement and compare two Cooley-Tukey Six-Step fast Fourier transforms and a Cooley-Tukey Four-Step variant against a high performing specialized FFT already implemented in the Basic Polynomial Algebra Subprograms (BPAS) library. We use optimization techniques found …


Research On The Regulation Problem Of The Integration Of Inland Shipping In The Yangtze River Delta, Yiyang Xiong Aug 2020

Research On The Regulation Problem Of The Integration Of Inland Shipping In The Yangtze River Delta, Yiyang Xiong

World Maritime University Dissertations

No abstract provided.


Research On Quantity Discount Pricing By Container Liner Shipping, Runzhe Zhao Aug 2020

Research On Quantity Discount Pricing By Container Liner Shipping, Runzhe Zhao

World Maritime University Dissertations

No abstract provided.


Application Of Harvard Analytical Framework In Shipping Enterprises Under Influence Of Covid-19 Pandemic A Case Of Shanghai International Port Group, Lei Wang Aug 2020

Application Of Harvard Analytical Framework In Shipping Enterprises Under Influence Of Covid-19 Pandemic A Case Of Shanghai International Port Group, Lei Wang

World Maritime University Dissertations

No abstract provided.


Research On Concentration Force Of Goods In Ports Across The Taiwan Strait, Yucong Xie Aug 2020

Research On Concentration Force Of Goods In Ports Across The Taiwan Strait, Yucong Xie

World Maritime University Dissertations

No abstract provided.


Research On The Economic Viability Of Mega Container Ship, Guozhen Peng Aug 2020

Research On The Economic Viability Of Mega Container Ship, Guozhen Peng

World Maritime University Dissertations

No abstract provided.


Research On The Logistics Development Model Of Shanghai Free Trade Zone, Yuhong Xie Aug 2020

Research On The Logistics Development Model Of Shanghai Free Trade Zone, Yuhong Xie

World Maritime University Dissertations

No abstract provided.


Evaluation Of China Shipping Hub-And-Spoke Network Based On Herfindahl-Hirschmann Index (Hhi), Wenjin Sun Aug 2020

Evaluation Of China Shipping Hub-And-Spoke Network Based On Herfindahl-Hirschmann Index (Hhi), Wenjin Sun

World Maritime University Dissertations

No abstract provided.


From Emission Trade Sysytem To Carbon Offset: Status And Progress Of Emission Control In Shipping Industry, Zhili Yao Aug 2020

From Emission Trade Sysytem To Carbon Offset: Status And Progress Of Emission Control In Shipping Industry, Zhili Yao

World Maritime University Dissertations

No abstract provided.


Wavelet Coherence Analysis With An Application Of Brain Images, Yiqian Fang Aug 2020

Wavelet Coherence Analysis With An Application Of Brain Images, Yiqian Fang

Arts & Sciences Electronic Theses and Dissertations

Wavelet analysis has become an emerging method in a wide range of applications with non-stationary data. In this work, we apply wavelets to tackle the problem of estimating dynamic association in a collection of multivariate non-stationary time series. Coherence is a common metric for linear dependence across signals. However, it assumes static dependence and does not sufficiently model many biological processes with time-evolving dependence structures. We explore continuous wavelet analysis for modeling and estimating such dynamic dependence under the replicated multivariate time series settings. Wavelet transformation provides a decomposition of signals that localizes in both time and frequency domains, hence …


A Theory Of Preimage Complexity: Data-Structures, Complexity Measures And Applications To Endofunctions And Associated Digraphs, Bradford M. Fournier-Eaton Aug 2020

A Theory Of Preimage Complexity: Data-Structures, Complexity Measures And Applications To Endofunctions And Associated Digraphs, Bradford M. Fournier-Eaton

University of New Orleans Theses and Dissertations

This dissertation develops a new theory of finite function complexity. This novel approach is based on the structure of preimage sets generated under repeat application of the inverse. We encode this information in our primary data-structure, an square matrix called the sigma matrix. This matrix allows us to easily encode information about the functional digraph and cycle structure of the associated endofunction. Additionally, the sigma matrix is of interest in its own right. The columns of sigma matrices are integer partitions of the domain size n, the size of the domain is always an eigenvalue of the sigma matrix, and …


The Second Law Of Thermodynamics And The Accumulation Theorem, Austin Maule Aug 2020

The Second Law Of Thermodynamics And The Accumulation Theorem, Austin Maule

Theses and Dissertations

In Serrin's proof of the Accumulation Theorem, the presence of an ideal gas G is assumed.

In 1979 at the University of Naples, Serrin (allegedly) proved that the ideal system G can be replaced by a more general ideal system and still have the Accumulation Theorem hold.

In this paper, we attempt to reconstruct Serrin's proof and supply a proof for a more general theorem stated in a paper of Coleman, Owen and Serrin.


Decompositions Of The Complete Mixed Graph By Mixed Stars, Chance Culver Aug 2020

Decompositions Of The Complete Mixed Graph By Mixed Stars, Chance Culver

Electronic Theses and Dissertations

In the study of mixed graphs, a common question is: What are the necessary and suffcient conditions for the existence of a decomposition of the complete mixed graph into isomorphic copies of a given mixed graph? Since the complete mixed graph has twice as many arcs as edges, then an obvious necessary condition is that the isomorphic copies have twice as many arcs as edges. We will prove necessary and suffcient conditions for the existence of a decomposition of the complete mixed graphs into mixed stars with two edges and four arcs. We also consider some special cases of decompositions …


Asymptotic Probability Of Incidence Relations Over Finite Fields, Adam Buck Aug 2020

Asymptotic Probability Of Incidence Relations Over Finite Fields, Adam Buck

Theses and Dissertations

Given four generic lines in FP3, we ask, "How many lines meet the four?" The answer depends on the field. When F = C, the answer is two. When F = R, the answer is either zero or two.

If we work over a finite field there are only finitely many projective lines. We compute the probability four lines are met by two. The main result is that as q approaches infinity, this probability approaches 1/2. Asymptotically, the other half of the time zero lines will meet the four.


Local Connectedness Of Bowditch Boundary Of Relatively Hyperbolic Groups, Ashani Dasgupta Aug 2020

Local Connectedness Of Bowditch Boundary Of Relatively Hyperbolic Groups, Ashani Dasgupta

Theses and Dissertations

If the Bowditch boundary of a finitely generated relatively hyperbolic group is connected, then, we show that it is locally connected. Bowditch showed that this is true provided the peripheral subgroups obey certain tameness condition. In this paper, we show that these tameness conditions are not necessary.


Earth Mover's Distance Between Grade Distribution Data With Fixed Mean, Jan Kretschmann Aug 2020

Earth Mover's Distance Between Grade Distribution Data With Fixed Mean, Jan Kretschmann

Theses and Dissertations

The Earth Mover's Distance (EMD) is examined on all theoretically possible grade distributions with the same grade point average (GPA). The numbers of distributions with the same EMD and GPA are encoded in the coefficients of a generating function. The theoretical mean EMD for grade distributions, that are sampled uniformly and independently at random, is computed from this function, and compared to real world grade data taken from several years. The data is further examined regarding the appearance of clusters that change when varying the distance threshold.