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Plessas, Demitri Joel. "Topos-like properties in two categories of graphs and graph-like features in an abstract category." CONNECT TO THIS TITLE ONLINE, 2008. http://etd.lib.umt.edu/theses/available/etd-05292008-131250/.
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Kissinger, Aleks. "Pictures of processes : automated graph rewriting for monoidal categories and applications to quantum computing." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:61fb3161-a353-48fc-8da2-6ce220cce6a2.
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This work is about diagrammatic languages, how they can be represented, and what they in turn can be used to represent. More specifically, it focuses on representations and applications of string diagrams. String diagrams are used to represent a collection of processes, depicted as "boxes" with multiple (typed) inputs and outputs, depicted as "wires". If we allow plugging input and output wires together, we can intuitively represent complex compositions of processes, formalised as morphisms in a monoidal category. While string diagrams are very intuitive, existing methods for defining them rigorously rely on topological notions that do not extend naturally to automated computation. The first major contribution of this dissertation is the introduction of a discretised version of a string diagram called a string graph. String graphs form a partial adhesive category, so they can be manipulated using double-pushout graph rewriting. Furthermore, we show how string graphs modulo a rewrite system can be used to construct free symmetric traced and compact closed categories on a monoidal signature. The second contribution is in the application of graphical languages to quantum information theory. We use a mixture of diagrammatic and algebraic techniques to prove a new classification result for strongly complementary observables. Namely, maximal sets of strongly complementary observables of dimension D must be of size no larger than 2, and are in 1-to-1 correspondence with the Abelian groups of order D. We also introduce a graphical language for multipartite entanglement and illustrate a simple graphical axiom that distinguishes the two maximally-entangled tripartite qubit states: GHZ and W. Notably, we illustrate how the algebraic structures induced by these operations correspond to the (partial) arithmetic operations of addition and multiplication on the complex projective line. The third contribution is a description of two software tools developed in part by the author to implement much of the theoretical content described here. The first tool is Quantomatic, a desktop application for building string graphs and graphical theories, as well as performing automated graph rewriting visually. The second is QuantoCoSy, which performs fully automated, model-driven theory creation using a procedure called conjecture synthesis.
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Grinshpun, Andrey Vadim. "Some problems in Graph Ramsey Theory." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/97767.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mathematics, 2015.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 149-156).
A graph G is r-Ramsey minimal with respect to a graph H if every r-coloring of the edges of G yields a monochromatic copy of H, but the same is not true for any proper subgraph of G. The study of the properties of graphs that are Ramsey minimal with respect to some H and similar problems is known as graph Ramsey theory; we study several problems in this area. Burr, Erdös, and Lovász introduced s(H), the minimum over all G that are 2- Ramsey minimal for H of [delta](G), the minimum degree of G. We find the values of s(H) for several classes of graphs H, most notably for all 3-connected bipartite graphs which proves many cases of a conjecture due to Szabó, Zumstein, and Zürcher. One natural question when studying graph Ramsey theory is what happens when, rather than considering all 2-colorings of a graph G, we restrict to a subset of the possible 2-colorings. Erdös and Hajnal conjectured that, for any fixed color pattern C, there is some [epsilon] > 0 so that every 2-coloring of the edges of a Kn, the complete graph on n vertices, which doesn't contain a copy of C contains a monochromatic clique on n[epsilon] vertices. Hajnal generalized this conjecture to more than 2 colors and asked in particular about the case when the number of colors is 3 and C is a rainbow triangle (a K3 where each edge is a different color); we prove Hajnal's conjecture for rainbow triangles. One may also wonder what would happen if we wish to cover all of the vertices with monochromatic copies of graphs. Let F = {F₁, F₂, . . .} be a sequence of graphs such that Fn is a graph on n vertices with maximum degree at most [delta]. If each Fn is bipartite, then the vertices of any 2-edge-colored complete graph can be partitioned into at most 2C[delta] vertex disjoint monochromatic copies of graphs from F, where C is an absolute constant. This result is best possible, up to the constant C.
by Andrey Vadim Grinshpun.
Ph. D.
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Al, Shumrani Mohammed Ahmed Musa. "Homotopy theory in algebraic derived categories." Thesis, University of Glasgow, 2006. http://theses.gla.ac.uk/1905/.
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In this thesis, we introduce some new notions in the derived category D+(fg) (R) of bounded below chain complexes of finite type over local commutative noetherian ring R with maximal ideal m and residue field K in chapter three and study their relations to each other. Also, we set up the Adams spectral sequence for chain complexes in D+(f,g) (R) in chapter four and study its convergence. To accomplish this task, we give two background chapters. We give some good account of chain complexes in chapter one. We review some basic homological algebra and give definition and basic properties of chain complexes. Then we study the homotopy category of chain complexes and we end chapter one with section about spectral sequences. Chapter two is about the derived category of a commutative ring. Section one is about localization of categories and left and right fractions. Then in section two, we give definition of triangulated categories and some of its basic properties and we end section two with definitions of homotopy limits and colimits. In section three, we show that the derived category is a triangulated category. In section four, we give definitions of the derived functors, the derived tensor product and the derived Hom. In chapter three, we start section one by giving some facts about local rings and we end this section by showing that every bounded below chain complex of finite type has a minimal free resolution. In section two, we show a derived analog of the Whitehead Theorem. In section three, we construct Postnikov towers for chain complexes. In section four, we define the Steenrod algebra. In section five, six and seven, we define irreducible, atomic, minimal atomic, no mod m detectable homology, H*-monogenic, nuclear chain complexes and the core of a chain complex. We show some various results relating these notions to each other and give some examples. In chapter four, we set up the Adams spectral sequence in section one and study its properties. In section two, we study homology localization and local homology. In section three, we define K[0]-nilpotent completion and we show that the Adams spectral sequence for a chain complex Y converges strongly to the homology of the K[0]-nilpotent completion of Y. In section four, we study the Adams spectral sequence’s convergence where we show that the K[0]-nilpotent completion for a bounded chain complex Y consisting of finitely generated free R-modules in each degree is isomorphic to the localization of Y with respect to the H*(—, K)-theory. In section five, we present some examples.
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Garbe, Frederik. "Extremal graph theory via structural analysis." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8869/.
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We discuss two extremal problems in extremal graph theory. First we establish a precise characterisation of 4-uniform hypergraphs with minimum codegree close to n/2 which contain a Hamilton 2-cycle. As a corollary we determine the exact Dirac threshold for Hamilton 2-cycles in 4-uniform hypergraphs, and we provide a polynomial-time algorithm which answers the corresponding decision problem for 4-graphs with minimum degree close to n/2. In contrast we also show that the corresponding decision problem for tight Hamilton cycles in dense k-graphs is NP-complete. Furthermore we study the following bootstrap percolation process: given a connected graph G, we infect an initial set A of vertices, and in each step a vertex v becomes infected if at least a p-proportion of its neighbours are infected. A set A which infects the whole graph is called a contagious set. Our main result states that for every pin (0,1] and for every connected graph G on n vertices the minimal size of a contagious set is less than 2pn or 1. This result is best-possible, but we provide a stronger bound in the case of graphs of girth at least five. Both proofs exploit the structure of a minimal counterexample.
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Fiala, Nick C. "Some topics in combinatorial design theory and algebraic graph theory /." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486402957198077.
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Poklewski-Koziell, Rowan. "Extensive categories, commutative semirings and Galois theory." Master's thesis, Faculty of Science, 2020. http://hdl.handle.net/11427/32412.
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We describe the Galois theory of commutative semirings as a Boolean Galois theory in the sense of Carboni and Janelidze. Such a Galois structure then naturally suggests an extension to commutative semirings of the classical theory of quadratic equations over commutative rings. We show, however, that our proposed generalization is impossible for connected commutative semirings which are not rings, leading to the conclusion that for the theory of quadratic equations, “minus is needed”. Finally, by considering semirings B which have no non-trivial additive inverses and no non-trivial zero divisors, we present an example of a normal extension of commutative semirings which has an underlying B-semimodule structure isomorphic to B×B.
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Edwards, C. S. "Some extremal problems in graph theory." Thesis, University of Reading, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373467.
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Weaver, Robert Wooddell. "Some problems in structural graph theory /." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487268021746449.
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Hatt, Justin Dale. "Online assessment of graph theory." Thesis, Brunel University, 2016. http://bura.brunel.ac.uk/handle/2438/13389.
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The objective of this thesis is to establish whether or not online, objective questions in elementary graph theory can be written in a way that exploits the medium of computer-aided assessment. This required the identification and resolution of question design and programming issues. The resulting questions were trialled to give an extensive set of answer files which were analysed to identify whether computer delivery affected the questions in any adverse ways and, if so, to identify practical ways round these issues. A library of questions spanning commonly-taught topics in elementary graph theory has been designed, programmed and added to the graph theory topic within an online assessment and learning tool used at Brunel University called Mathletics. Distracters coded into the questions are based on errors students are likely to make, partially evidenced by final examination scripts. Questions were provided to students in Discrete Mathematics modules with an extensive collection of results compiled for analysis. Questions designed for use in practice environments were trialled on students from 2007 – 2008 and then from 2008 to 2014 inclusive under separate testing conditions. Particular focus is made on the relationship of facility and discrimination between comparable questions during this period. Data is grouped between topic and also year group for the 2008 – 2014 tests, namely 2008 to 2011 and 2011 to 2014, so that it may then be determined what factors, if any, had an effect on the overall results for these questions. Based on the analyses performed, it may be concluded that although CAA questions provide students with a means for improving their learning in this field of mathematics, what makes a question more challenging is not solely based on the number of ways a student can work out his/her solution but also on several other factors that depend on the topic itself.
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Letzter, Shoham. "Extremal graph theory with emphasis on Ramsey theory." Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709415.
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Holloway, Nick. "Parallel algorithms in graph theory and algebra." Thesis, University of Warwick, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338724.
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Harris, A. J. "Problems and conjectures in extremal graph theory." Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305148.
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Loveland, Susan M. "The Reconstruction Conjecture in Graph Theory." DigitalCommons@USU, 1985. https://digitalcommons.usu.edu/etd/7022.
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In this paper we show that specific classes of graphs are reconstructible; we explore the relationship between the. reconstruction and edge-reconstruction conjectures; we prove that several classes of graphs are actually Harary to the reconstructible; and we give counterexamples reconstruction and edge-reconstruction conjectures for infinite graphs.
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Smithers, Dayna Brown. "Graph Theory for the Secondary School Classroom." Digital Commons @ East Tennessee State University, 2005. https://dc.etsu.edu/etd/1015.
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After recognizing the beauty and the utility of Graph Theory in solving a variety of problems, the author decided that it would be a good idea to make the subject available for students earlier in their educational experience. In this thesis, the author developed four units in Graph Theory, namely Vertex Coloring, Minimum Spanning Tree, Domination, and Hamiltonian Paths and Cycles, which are appropriate for high school level.
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Schuerger, Houston S. "Contributions to Geometry and Graph Theory." Thesis, University of North Texas, 2020. https://digital.library.unt.edu/ark:/67531/metadc1707341/.
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In geometry we will consider n-dimensional generalizations of the Power of a Point Theorem and of Pascal's Hexagon Theorem. In generalizing the Power of a Point Theorem, we will consider collections of cones determined by the intersections of an (n-1)-sphere and a pair of hyperplanes. We will then use these constructions to produce an n-dimensional generalization of Pascal's Hexagon Theorem, a classical plane geometry result which states that "Given a hexagon inscribed in a conic section, the three pairs of continuations of opposite sides meet on a straight line." Our generalization of this theorem will consider a pair of n-simplices intersecting an (n-1)-sphere, and will conclude with the intersections of corresponding faces lying in a hyperplane. In graph theory we will explore the interaction between zero forcing and cut-sets. The color change rule which lies at the center of zero forcing says "Suppose that each of the vertices of a graph are colored either blue or white. If u is a blue vertex and v is its only white neighbor, then u can force v to change to blue." The concept of zero forcing was introduced by the AIM Minimum Rank - Special Graphs Work Group in 2007 as a way of determining bounds on the minimum rank of graphs. Later, Darren Row established results concerning the zero forcing numbers of graphs with a cut-vertex. We will extend his work by considering graphs with arbitrarily large cut-sets, and the collections of components they yield, to determine results for the zero forcing numbers of these graphs.
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Vella, Antoine. "A Fundamentally Topological Perspective on Graph Theory." Thesis, University of Waterloo, 2005. http://hdl.handle.net/10012/1033.
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We adopt a novel topological approach for graphs, in which edges are modelled as points as opposed to arcs. The model of classical topologized graphs translates graph isomorphism into topological homeomorphism, so that all combinatorial concepts are expressible in purely topological language. This allows us to extrapolate concepts from finite graphs to infinite graphs equipped with a compatible topology, which, dropping the classical requirement, need not be unique. We bring standard concepts from general topology to bear upon questions of a combinatorial inspiration, in an infinite setting.
We show how (possibly finite) graph-theoretic paths are, without any technical subterfuges, a subclass of a broad category of topological spaces, namely paths, that includes Hausdorff arcs, the real line and all connected orderable spaces (of arbitrary cardinality). We show that all paths, and the topological generalizations of cycles, are topologized graphs. We use feeble regularity to explore relationships between the topologies on the vertex set and the whole space. We employ compactness and weak normality to prove the existence of our analogues for minimal spanning sets and fundamental cycles. In this framework, we generalize theorems from finite graph theory to a broad class of topological structures, including the facts that fundamental cycles are a basis for the cycle space, and the orthogonality between bond spaces and cycle spaces. We show that this can be accomplished in a setup where the set of edges of a cycle has a loose relationship with the cycle itself. It turns out that, in our model, feeble regularity excludes several pathologies, including one identified previously by Diestel and Kuehn, in a very different approach which addresses the same issues. Moreover, the spaces surgically constructed by the same authors are feebly regular and, if the original graph is 2-connected, compact. We consider an attractive relaxation of the T1 separation axiom, namely the S1 axiom, which leads to a topological universe parallel to the usual one in mainstream topology. We use local connectedness to unify graph-theoretic trees with the dendrites of continuum theory and a more general class of well behaved dendritic spaces, within the class of ferns.
We generalize results of Whyburn and others concerning dendritic spaces to ferns, and show how cycles and ferns, in particular paths, are naturally S1 spaces, and hence may be viewed as topologized hypergraphs. We use topological separation properties with a distinct combinatorial flavour to unify the theory of cycles, paths and ferns. This we also do via a setup involving total orders, cyclic orders and partial orders. The results on partial orders are similar to results of Ward and Muenzenberger and Smithson in the more restrictive setting of Hausdorff dendritic spaces. Our approach is quite different and, we believe, lays the ground for an appropriate notion of completion which links Freudenthal ends of ferns simultaneously with the work of Polat for non-locally-finite graphs and the paper of Allen which recognizes the unique dendritic compactification of a rim-compact dendritic space as its Freudenthal compactification.
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Schrader, Paul T. "HOM-TENSOR CATEGORIES." Bowling Green State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1520959380837247.
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Osorno, Angélica María. "An infinite loop space structure for K-theory of bimonoidal categories." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/60104.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mathematics, 2010.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (p. 63-64).
In recent work of Baas-Dundas-Richter-Rognes, the authors introduce the notion of the K- theory of a bimonoidal category R, and show that it is equivalent to the algebraic K-theory space of the ring spectrum KR. In this thesis we show that K(R) is the group completion of the classifying space of the 2-category ModR of modules over R, and show that ModR is a symmetric monoidal 2-category. We explain how to use this symmetric monoidal structure to produce a [Gamma]-(2-category), which gives an infinite loop space structure on K(R). We show that the equivalence mentioned above is an equivalence of infinite loop spaces.
by Angélica María Osorno.
Ph.D.
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Chebolu, Sunil Kumar. "Refinements of chromatic towers and Krull-Schmidt decompositions in stable homotopy categories /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/5743.
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Johnson, Mark William. "Enriched sheaf theory as a framework for stable homotopy theory /." Thesis, Connect to this title online; UW restricted, 1999. http://hdl.handle.net/1773/5775.
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Abdulwahid, Adnan Hashim. "Cofree objects in the categories of comonoids in certain abelian monoidal categories." Diss., University of Iowa, 2016. https://ir.uiowa.edu/etd/2032.
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We investigate cofree coalgebras, and limits and colimits of coalgebras in some abelian monoidal categories of interest, such as bimodules over a ring, and modules and comodules over a bialgebra or Hopf algebra. We nd concrete generators for the categories of coalgebras in these monoidal categories, and explicitly construct cofree coalgebras, products and limits of coalgebras in each case. This answers an open question in [4] on the existence of a cofree coring, and constructs the cofree (co)module coalgebra on a B-(co)module, for a bialgebra B.
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Bar, Krzysztof. "Automated rewriting for higher categories and applications to quantum theory." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:ba1d3341-873d-4255-8400-c2277b7648f3.
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The contribution of this thesis is a novel framework for rewriting in higher categories. Its theoretical foundation is the theory of quasistrict higher categories and the practical realisation is a proof assistant Globular. The framework introduces the notions of diagrams and signatures as new mutually-recursive structures that give the algebraic basis for the approach. These structures are related the notion of an n-polygraph, but allow reasoning about quasistrict higher categorical structures in a way amenable to computer implementation. Building on this, we propose a new definition of a quasistrict 4-category, and prove a result that in a quasistrict 4-category, an adjunction of 1-morphisms gives rise to a coherent adjunction satisfying the butterfly equations.
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Rittenhouse, Michelle L. "Properties and Recent Applications in Spectral Graph Theory." VCU Scholars Compass, 2008. http://scholarscompass.vcu.edu/etd/1126.
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There are numerous applications of mathematics, specifically spectral graph theory, within the sciences and many other fields. This paper is an exploration of recent applications of spectral graph theory, including the fields of chemistry, biology, and graph coloring. Topics such as the isomers of alkanes, the importance of eigenvalues in protein structures, and the aid that the spectra of a graph provides when coloring a graph are covered, as well as others.The key definitions and properties of graph theory are introduced. Important aspects of graphs, such as the walks and the adjacency matrix are explored. In addition, bipartite graphs are discussed along with properties that apply strictly to bipartite graphs. The main focus is on the characteristic polynomial and the eigenvalues that it produces, because most of the applications involve specific eigenvalues. For example, if isomers are organized according to their eigenvalues, a pattern comes to light. There is a parallel between the size of the eigenvalue (in comparison to the other eigenvalues) and the maximum degree of the graph. The maximum degree of the graph tells us the most carbon atoms attached to any given carbon atom within the structure. The Laplacian matrix and many of its properties are discussed at length, including the classical Matrix Tree Theorem and Cayley's Tree Theorem. Also, an alternative approach to defining the Laplacian is explored and compared to the traditional Laplacian.
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Crumley, Michael N. Jr. "Ultraproducts of Tannakian Categories and Generic Representation Theory of Unipotent Algebraic Groups." University of Toledo / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1279224151.
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Pejić, Snežana. "Algebraic graph theory in the analysis of frequency assignment problems." Thesis, London School of Economics and Political Science (University of London), 2008. http://etheses.lse.ac.uk/129/.
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Frequency Assignment Problems (FAPs) arise when transmitters need to be allocated frequencies with the aim of minimizing interference, whilst maintaining an efficient use of the radio spectrum. In this thesis FAPs are seen as generalised graph colouring problems, where transmitters are represented by vertices, and their interactions by weighted edges. Solving FAPs often relies on known structural properties to facilitate algorithms. When no structural information is available explicitly, obtaining it from numerical data is difficult. This lack of structural information is a key underlying motivation for the research work in this thesis. If there are TV transmitters to be assigned, we assume as given an N x N "influence matrix" W with entries Wij representing influence between transmitters i and j. From this matrix we derive the Laplacian matrix L = D—W, where D is a diagonal matrix whose entries da are the sum of all influences working in transmitter i. The focus of this thesis is the study of mathematical properties of the matrix L. We généralisé certain properties of the Laplacian eigenvalues and eigenvectors that hold for simple graphs. We also observe and discuss changes in the shape of the Laplacian eigenvalue spectrum due to modifications of a FAP. We include a number of computational experiments and generated simulated examples of FAPs for which we explicitly calculate eigenvalues and eigenvectors in order to test the developed theoretical results. We find that the Laplacians prove useful in identifying certain types of problems, providing structured approach to reducing the original FAP to smaller size subproblems, hence assisting existing heuristic algorithms for solving frequency assignments. In that sense we conclude that analysis of the Laplacians is a useful tool for better understanding of FAPs.
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Panchadcharam, Elango. "Categories of Mackey functors." Doctoral thesis, Electronic version, 2007. http://hdl.handle.net/1959.14/119.
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Thesis by publication.Thesis (PhD)--Macquarie University (Division of Information & Communication Sciences, Dept. of Mathematics), 2007.
Bibliography: p. 119-123.
Introduction -- Mackey functors on compact closed categories -- Lax braidings and the lax centre -- On centres and lax centres for promonoidal catagories -- Pullback and finite coproduct preserving functors between categories of permutation representations -- Conclusion.
This thesis studies the theory of Mackey functors as an application of enriched category theory and highlights the notions of lax braiding and lax centre for monoidal categories and more generally promonoidal categories ... The third contribution of this thesis is the study of functors between categories of permutation representations.
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Stanculescu, Alexandru. "Homotopy theories on enriched categories and on comonoids." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=115852.
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The main purpose of this work is to study model category structures (in the sense of Quillen) on the categories of small categories and small symmetric multicategories enriched over an arbitrary monoidal model category. Among these model structures, there is one of the greatest importance in applications. We call it the Dwyer-Kan model structure (for enriched categories or enriched symmetric multicategories), and a large amount of this work is dedicated to establishing it for different choices of monoidal model categories. Another model structure that we study is what we call the fibred model structure, again for both small categories and small symmetric multicategories enriched over a suitable monoidal model category.The other purpose of this work is to study model category structures on the category of comonoids in a monoidal model category.
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Robinson, Laura Ann. "Graph Theory for the Middle School." Digital Commons @ East Tennessee State University, 2006. https://dc.etsu.edu/etd/2226.
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After being introduced to graph theory and realizing how it can be utilized to solve real-world problems, the author decided to create modules of study on graph theory appropriate for middle school students. In this thesis, four modules were developed in the area of graph theory: an Introduction to Terms and Definitions, Graph Families, Graph Operations, and Graph Coloring. It is written as a guide for middle school teachers to prepare teaching units on graph theory.
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Dawson, Shelly Jean. "Minimal congestion trees." CSUSB ScholarWorks, 2006. https://scholarworks.lib.csusb.edu/etd-project/3005.
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Analyzes the results of M.I. Ostrovskii's theorem of inequalities which estimate the minimal edge congestion for finite simple graphs. Uses the generic results of the theorem to examine and further reduce the parameters of inequalities for specific families of graphs, particularly complete graphs and complete bipartite graphs. Also, explores a possible minimal congestion tree for some grids while forming a conjecture for all grids.
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Wollan, Paul. "Extremal Functions for Graph Linkages and Rooted Minors." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/7552.
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Extremal Functions for Graph Linkages and Rooted Minors
Paul Wollan
137 pages
Directed by: Robin Thomas
A graph G is k-linked if for any 2k distinct vertices s_1,..., s_k,t_1,..., t_k there exist k vertex disjoint paths P_1,...,P_k such that the endpoints of P_i are s_i and t_i. Determining the
existence of graph linkages is a classic problem in graph theory with numerous applications. In this thesis, we examine sufficient conditions that guarantee a graph to be k-linked and give the following theorems.
(A) Every 2k-connected graph on n vertices with 5kn edges is k-linked.
(B) Every 6-connected graph on n vertices with 5n-14 edges is 3-linked.
The proof method for Theorem (A) can also be used
to give an elementary proof of the weaker bound that 8kn edges suffice. Theorem (A) improves upon the previously best known bound due to Bollobas and Thomason stating that 11kn edges suffice. The edge bound in Theorem (B) is optimal in that there exist 6-connected graphs on n vertices with 5n-15 edges that are not 3-linked.
The methods used prove Theorems (A) and (B) extend to a more general structure than graph linkages called rooted minors. We generalize the proof
methods for Theorems (A) and (B) to find edge bounds for general rooted minors, as well as finding the optimal edge bound for a specific
family of bipartite rooted minors.
We conclude with two graph theoretical applications of graph linkages. The first is to the problem of determining when a small number of vertices can be used to cover all the odd cycles in a graph. The second is a simpler proof of a result of Boehme, Maharry and Mohar on complete
minors in huge graphs of bounded tree-width.
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Krzywkowski, Marcin Piotr. "Hat problem on a graph." Thesis, University of Exeter, 2012. http://hdl.handle.net/10036/4019.
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The topic of this thesis is the hat problem. In this problem, a team of n players enters a room, and a blue or red hat is randomly placed on the head of each player. Every player can see the hats of all of the other players but not his own. Then each player must simultaneously guess the color of his own hat or pass. The team wins if at least one player guesses his hat color correctly and no one guesses his hat color wrong, otherwise the team loses. The aim is to maximize the probability of winning. This thesis is based on publications, which form the second chapter. In the first chapter we give an overview of the published results. In Section 1.1 we introduce to the hat problem and the hat problem on a graph, where vertices correspond to players, and a player can see the adjacent players. To the hat problem on a graph we devote the next few sections. First, we give some fundamental theorems about the problem. Then we solve the hat problem on trees, cycles, and unicyclic graphs. Next we consider the hat problem on graphs with a universal vertex. We also investigate the problem on graphs with a neighborhood-dominated vertex. In addition, we consider the hat problem on disconnected graphs. Next we investigate the problem on graphs such that the only known information are degrees of vertices. We also present Nordhaus-Gaddum type inequalities for the hat problem on a graph. In Section 1.6 we investigate the hat problem on directed graphs. The topic of Section 1.7 is the generalized hat problem with q >= 2 colors. A modified hat problem is considered in Section 1.8. In this problem there are n >= 3 players and two colors. The players do not have to guess their hat colors simultaneously and we modify the way of making a guess. We give an optimal strategy for this problem which guarantees the win. Applications of the hat problem and its connections to different areas of science are presented in Section 1.9. We also give there a comprehensive list of variations of the hat problem considered in the literature.
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Raskin, Samuel David. "Chiral Principal Series Categories." Thesis, Harvard University, 2014. http://dissertations.umi.com/gsas.harvard:11525.
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This thesis begins a study of principal series categories in geometric representation theory using the Beilinson-Drinfeld theory of chiral algebras. We study Whittaker objects in the unramified principal series category. This provides an alternative approach to the Arkhipov-Bezrukavnikov theory of Iwahori-Whittaker sheaves that exploits the geometry of the Feigin-Frenkel semi-infinite flag manifold.Mathematics
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Kelly, Jack. "Exact categories, Koszul duality, and derived analytic algebra." Thesis, University of Oxford, 2018. http://ora.ox.ac.uk/objects/uuid:27064241-0ad3-49c3-9d7d-870d51fe110b.
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Recent work of Bambozzi, Ben-Bassat, and Kremnitzer suggests that derived analytic geometry over a valued field k can be modelled as geometry relative to the quasi-abelian category of Banach spaces, or rather its completion Ind(Bank). In this thesis we develop a robust theory of homotopical algebra in Ch(E) for E any sufficiently 'nice' quasi-abelian, or even exact, category. Firstly we provide sufficient conditions on weakly idempotent complete exact categories E such that various categories of chain complexes in E are equipped with projective model structures. In particular we show that as soon as E has enough projectives, the category Ch+(E) of bounded below complexes is equipped with a projective model structure. In the case that E also admits all kernels we show that it is also true of Ch≥0(E), and that a generalisation of the Dold-Kan correspondence holds. Supplementing the existence of kernels with a condition on the existence and exactness of certain direct limit functors guarantees that the category of unbounded chain complexes Ch(E) also admits a projective model structure. When E is monoidal we also examine when these model structures are monoidal. We then develop the homotopy theory of algebras in Ch(E). In particular we show, under very general conditions, that categories of operadic algebras in Ch(E) can be equipped with transferred model structures. Specialising to quasi-abelian categories we prove our main theorem, which is a vast generalisation of Koszul duality. We conclude by defining analytic extensions of the Koszul dual of a Lie algebra in Ind(Bank).
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Andersen, Aaron. "GraphShop: An Interactive Software Environment for Graph Theory Research and Applications." DigitalCommons@USU, 2011. https://digitalcommons.usu.edu/etd/896.
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Graph Theory is the mathematical study of the structure of abstract relationships between objects. Although these constructions (graphs) are themselves purely theoretical, their ability to model pair-wise relationships in systems of arbitrary complexity yields abundant direct correspondence with numerous important physical and societal systems in the real world. Additionally, the simple discrete nature of fundamental graph structures allows for easy pseudo-geometric visualization of graphs in a wide variety of ways. Taken together, these two properties suggest that graph theory teaching, research, and applications would benefit greatly from the use of a unified software environment for graph construction, interaction, and visualization.
Based on this need, a comprehensive survey was undertaken of existing graph theory software packages, programs, and libraries to determine the suitability of each for use as a graph theory teaching and research tool. Some of the desired components (especially in the realm of graph visualization) were found to be implemented in several current tools and systems, but no single system was located with the ability to perform all such functions together in a coordinated way.
Graph Shop (the Graph Theory Workshop) is a new software package for graph theory research and applications. It was designed to be usable by students and graph theory beginners yet powerful enough to assist with advanced graph theory research. It runs on a variety of platforms and is available for free under the GNU GPL open source license.
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Hahn, Rebekah D. "K(1)-local Iwasawa theory /." Thesis, Connect to this title online; UW restricted, 2003. http://hdl.handle.net/1773/5736.
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McCourt, Grace Ann. "The Dishonest Salesperson Problem." Ashland University Honors Theses / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=auhonors1494006002818757.
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Potter, John R. "Pseudo-triangulations on closed surfaces." Worcester, Mass. : Worcester Polytechnic Institute, 2008. http://www.wpi.edu/Pubs/ETD/Available/etd-021408-102227/.
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Lockridge, Keir H. "The generating hypothesis in general stable homotopy categories /." Thesis, Connect to this title online; UW restricted, 2006. http://hdl.handle.net/1773/5817.
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Burns, Jonathan. "Recursive Methods in Number Theory, Combinatorial Graph Theory, and Probability." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5193.
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Recursion is a fundamental tool of mathematics used to define, construct, and analyze mathematical objects. This work employs induction, sieving, inversion, and other recursive methods to solve a variety of problems in the areas of algebraic number theory, topological and combinatorial graph theory, and analytic probability and statistics. A common theme of recursively defined functions, weighted sums, and cross-referencing sequences arises in all three contexts, and supplemented by sieving methods, generating functions, asymptotics, and heuristic algorithms.
In the area of number theory, this work generalizes the sieve of Eratosthenes to a sequence of polynomial values called polynomial-value sieving. In the case of quadratics, the method of polynomial-value sieving may be characterized briefly as a product presentation of two binary quadratic forms. Polynomials for which the polynomial-value sieving yields all possible integer factorizations of the polynomial values are called recursively-factorable. The Euler and Legendre prime producing polynomials of the form n2+n+p and 2n2+p, respectively, and Landau's n2+1 are shown to be recursively-factorable. Integer factorizations realized by the polynomial-value sieving method, applied to quadratic functions, are in direct correspondence with the lattice point solutions (X,Y) of the conic sections aX2+bXY +cY2+X-nY=0. The factorization structure of the underlying quadratic polynomial is shown to have geometric properties in the space of the associated lattice point solutions of these conic sections.
In the area of combinatorial graph theory, this work considers two topological structures that are used to model the process of homologous genetic recombination: assembly graphs and chord diagrams. The result of a homologous recombination can be recorded as a sequence of signed permutations called a micronuclear arrangement. In the assembly graph model, each micronuclear arrangement corresponds to a directed Hamiltonian polygonal path within a directed assembly graph. Starting from a given assembly graph, we construct all the associated micronuclear arrangements. Another way of modeling genetic rearrangement is to represent precursor and product genes as a sequence of blocks which form arcs of a circle. Associating matching blocks in the precursor and product gene with chords produces a chord diagram. The braid index of a chord diagram can be used to measure the scope of interaction between the crossings of the chords. We augment the brute force algorithm for computing the braid index to utilize a divide and conquer strategy. Both assembly graphs and chord diagrams are closely associated with double occurrence words, so we classify and enumerate the double occurrence words based on several notions of irreducibility. In the area of analytic probability, moments abstractly describe the shape of a probability distribution. Over the years, numerous varieties of moments such as central moments, factorial moments, and cumulants have been developed to assist in statistical analysis. We use inversion formulas to compute high order moments of various types for common probability distributions, and show how the successive ratios of moments can be used for distribution and parameter fitting. We consider examples for both simulated binomial data and the probability distribution affiliated with the braid index counting sequence. Finally we consider a sequence of multiparameter binomial sums which shares similar properties with the moment sequences generated by the binomial and beta-binomial distributions. This sequence of sums behaves asymptotically like the high order moments of the beta distribution, and has completely monotonic properties.
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McSween, Alexandra. "Affine Oriented Frobenius Brauer Categories and General Linear Lie Superalgebras." Thesis, Université d'Ottawa / University of Ottawa, 2021. http://hdl.handle.net/10393/42342.
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To any Frobenius superalgebra A we associate an oriented Frobenius Brauer category and an affine oriented Frobenius Brauer categeory. We define natural actions of these categories on categories of supermodules for general linear Lie superalgebras gl_m|n(A) with entries in A. These actions generalize those on module categories for general linear Lie superalgebras and queer Lie superalgebras, which correspond to the cases where A is the ground field and the two-dimensional Clifford superalgebra, respectively. We include background on monoidal supercategories and Frobenius superalgebras and discuss some possible further directions.
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Bessy, Stéphane. "Some problems in graph theory and graphs algorithmic theory." Habilitation à diriger des recherches, Université Montpellier II - Sciences et Techniques du Languedoc, 2012. http://tel.archives-ouvertes.fr/tel-00806716.
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This document is a long abstract of my research work, concerning graph theory and algorithms on graphs. It summarizes some results, gives ideas of the proof for some of them and presents the context of the different topics together with some interesting open questions connected to them The first part precises the notations used in the rest of the paper; the second part deals with some problems on cycles in digraphs; the third part is an overview of two graph coloring problems and one problem on structures in colored graphs; finally the fourth part focus on some results in algorithmic graph theory, mainly in parametrized complexity.
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Mahoney, James Raymond. "Tree Graphs and Orthogonal Spanning Tree Decompositions." PDXScholar, 2016. http://pdxscholar.library.pdx.edu/open_access_etds/2944.
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Given a graph G, we construct T(G), called the tree graph of G. The vertices of T(G) are the spanning trees of G, with edges between vertices when their respective spanning trees differ only by a single edge. In this paper we detail many new results concerning tree graphs, involving topics such as clique decomposition, planarity, and automorphism groups. We also investigate and present a number of new results on orthogonal tree decompositions of complete graphs.
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Benecke, Stephen. "Higher order domination of graphs." Thesis, Stellenbosch : University of Stellenbosch, 2004. http://hdl.handle.net/10019.1/16257.
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Thesis (MSc)--University of Stellenbosch, 2004.ENGLISH ABSTRACT: Motivation for the study of protection strategies for graphs is rooted in antiquity and has evolved as a subdiscipline of graph theory since the early 1990s. Using, as a point of departure, the notions of weak Roman domination and secure domination (where protection of a graph is required against a single attack) an initial framework for higher order domination was introduced in 2002 (allowing for the protection of a graph against an arbitrary finite, or even infinite, number of attacks). In this thesis, the theory of higher order domination in graphs is broadened yet further to include the possibility of an arbitrary number of guards being stationed at a vertex. The thesis firstly provides a comprehensive survey of the combinatorial literature on Roman domination, weak Roman domination, secure domination and other higher order domination strategies, with a view to summarise the state of the art in the theory of higher order graph domination as at the start of 2004. Secondly, a generalised framework for higher order domination is introduced in two parts: the first catering for the protection of a graph against a finite number of consecutive attacks, and the second concerning the perpetual security of a graph (protection of the graph against an infinite number of consecutive attacks). Two types of higher order domination are distinguished: smart domination (requiring the existence of a protection strategy for any sequence of consecutive attacks of a pre–specified length, but leaving it up to a strategist to uncover such a guard movement strategy for a particular instance of the attack sequence), and foolproof domination (requiring that any possible guard movement strategy be a successful protection strategy for the graph in question). Properties of these higher order domination parameters are examined—first by investigating the application of known higher order domination results from the literature, and secondly by obtaining new results, thereby hopefully improving current understanding of these domination parameters. Thirdly, the thesis contributes by (i) establishing higher order domination parameter values for some special graph classes not previously considered (such as complete multipartite graphs, wheels, caterpillars and spiders), by (ii) summarising parameter values for special graph classes previously established (such as those for paths, cycles and selected cartesian products), and by (iii) improving higher order domination parameter bounds previously obtained (in the case of the cartesian product of two cycles). Finally, a clear indication of unresolved problems in higher order graph domination is provided in the conclusion to this thesis, together with some suggestions as to possibly desirable future generalisations of the theory.
AFRIKAANSE OPSOMMING: Die motivering vir die studie van verdedigingstrategie¨e vir grafieke het sy ontstaan in die antieke wˆereld en het sedert die vroe¨e 1990s as ’n subdissipline in grafiekteorie begin ontwikkel. Deur gebruik te maak van die idee van swak Romynse dominasie en versterkte dominasie (waar verdediging van ’n grafiek teen ’n enkele aanval vereis word) het ’n aanvangsraamwerk vir ho¨er– orde dominasie (wat ’n grafiek teen ’n veelvuldige, of selfs oneindige aantal, aanvalle verdedig) in 2002 die lig gesien. Die teorie van ho¨er–orde dominasie in grafieke word in hierdie tesis verbreed, deur toe te laat dat ’n arbitrˆere aantal wagte by elke punt van die grafiek gestasioneer mag word. Eerstens voorsien die tesis ’n omvangryke oorsig van die kombinatoriese literatuur oor Romynse dominasie, swak Romynse dominasie, versterkte dominasie en ander ho¨er–orde dominasie strategie ¨e, met die doel om die kundigheid betreffende die teorie van ho¨er–orde dominasie, soos aan die begin van 2004, op te som. Tweedens word ’n veralgemeende raamwerk vir ho¨er–orde dominasie bekendgestel, en wel in twee dele. Die eerste deel maak voorsiening vir die verdediging van ’n grafiek teen ’n eindige aantal opeenvolgende aanvalle, terwyl die tweede deel betrekking het op die oneindige sekuriteit van ’n grafiek (verdediging teen ’n oneindige aantal opeenvolgende aanvalle). Daar word tussen twee tipes h¨oer–orde dominasie onderskei: intelligente dominasie (wat slegs die bestaan van ’n verdedigingstrategie vir enige reeks opeenvolgende aanvalle vereis, maar dit aan ’n strateeg oorlaat om ’n suksesvolle bewegingstrategie vir die verdediging teen ’n spesifieke reeks aanvalle te vind), en onfeilbare dominasie (wat vereis dat enige moontlike bewegingstrategie resulteer in ’n suksesvolle verdedigingstrategie vir die betrokke grafiek). Eienskappe van hierdie ho¨er–orde dominasie parameters word ondersoek, deur eerstens die toepasbaarheid van bekende ho¨er–orde dominasie resultate vanuit die literatuur te assimileer, en tweedens nuwe resultate te bekom, in die hoop om die huidige kundigheid met betrekking tot hierdie dominasie parameters te verbreed. Derdens word ’n bydrae gelewer deur (i) ho¨er–orde dominasie parameterwaardes vas te stel vir sommige spesiale klasse grafieke wat nie voorheen ondersoek is nie (soos volledig veelledige grafieke, wiele, ruspers en spinnekoppe), deur (ii) parameterwaardes wat reeds bepaal is (soos byvoorbeeld di´e vir paaie, siklusse en sommige kartesiese produkte) op te som, en deur (iii) bekende ho¨er–orde dominasie parametergrense te verbeter (in die geval van die kartesiese produk van twee siklusse). Laastens word ’n aanduiding van oop probleme in die teorie van ho¨er–orde dominasie in die slothoofstuk van die tesis voorsien, tesame met voorstelle ten opsigte van moontlik sinvolle veralgemenings van die teorie.
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Alcock, Lara. "Categories, definitions and mathematics : student reasoning about objects in analysis." Thesis, University of Warwick, 2001. http://wrap.warwick.ac.uk/56117/.
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This thesis has two integrated components, one theoretical and one investigative. The theoretical component considers human reason about categories of objects. First, it proposes that the standards of argumentation in everyday life are variable, with emphasis on direct generalisation, whereas standards in mathematics are more fixed and require abstraction of properties. Second, it accounts for the difficulty of the transition to university mathematics by considering the impact of choosing formal definitions upon the nature of categories and argumentation. Through this it unifies established theories and observations regarding student behaviours at this level. Finally, it addresses the question of why Analysis seems particularly difficult, by considering the relative accessibility of its visual representations and its formal definitions. The investigative component is centred on a qualitative study, the main element of which is a series of interviews with students attending two different first courses in Real Analysis. One of these courses is a standard lecture course, the other involves a classroom-based, problem-solving approach. Grounded theory data analysis methods are used to interpret the data, identifying behaviours exhibited when students reason about specific objects and whole categories. These behaviours are linked to types of understanding as distinguished in the mathematics education literature. The student's visual or nonvisual reasoning style and their sense of authority, whether "internal" or "external" are identified as causal factors in the types of understanding a student develops. The course attended appears as an intervening factor. A substantive theory is developed to explain the contributions of these factors. This leads to improvement of the theory developed in the theoretical component. Finally, the study is reviewed and the implications of its findings for the teaching and learning of mathematics at this level are considered.
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Micu, Eliade Mihai. "Graph minors and Hadwiger's conjecture." Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1123259686.
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Thesis (Ph. D.)--Ohio State University, 2005.Title from first page of PDF file. Document formatted into pages; contains viii, 80 p.; also includes graphics. Includes bibliographical references (p. 80). Available online via OhioLINK's ETD Center
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Scherotzke, Sarah. "On Auslander-Reiten theory for algebras and derived categories." Thesis, University of Oxford, 2009. http://ora.ox.ac.uk/objects/uuid:ad4cd5a8-34b6-4725-a2a4-a3f08994618b.
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This thesis consists of three parts. In the first part we look at Hopf algebras. We classify pointed rank one Hopf algebras over fields of prime characteristic which are generated as algebras by the first term of the coradical filtration. These Hopf algebras were classified by Radford and Krop for fields of characteristic zero. We obtain three types of Hopf algebras presented by generators and relations. The third type is new and has not previously appeared in literature. The second part of this thesis deals with Auslander-Reiten theory of finitedimensional algebras over fields. We consider G-transitive algebras and develop necessary conditions for them to have Auslander-Reiten components with Euclidean tree class. Thereby a result in [F3, 4.6] is corrected and generalized. We apply these results to G-transitive blocks of the universal enveloping algebras of restricted p-Lie algebras. Finally we deduce a condition for a smash product of a local basic algebra Λ with a commutative semi-simple group algebra to have components with Euclidean tree class, in terms of the components of the Auslander-Reiten quiver of Λ. In the last part we introduce and analyze Auslander-Reiten components for the bounded derived category of a finite-dimensional algebra. We classify derived categories whose Auslander-Reiten quiver has either a finite stable component or a stable component with finite Dynkin tree class or a bounded stable component. Their Auslander-Reiten quiver is determined. We use these results to show that certain algebras are piecewise hereditary. Also a necessary condition for the existence of components of Euclidean tree class is deduced. We determine components that contain shift periodic complexes.
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Lin, Matthew. "Graph Cohomology." Scholarship @ Claremont, 2016. https://scholarship.claremont.edu/hmc_theses/82.
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What is the cohomology of a graph? Cohomology is a topological invariant and encodes such information as genus and euler characteristic. Graphs are combinatorial objects which may not a priori admit a natural and isomorphism invariant cohomology ring. In this project, given any finite graph G, we constructively define a cohomology ring H*(G) of G. Our method uses graph associahedra and toric varieties. Given a graph, there is a canonically associated convex polytope, called the graph associahedron, constructed from G. In turn, a convex polytope uniquely determines a toric variety. We synthesize these results, and describe the cohomology of the associated variety directly in terms of the graph G itself.
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Green, Hannah E. "Differentiating Between a Protein and its Decoy Using Nested Graph Models and Weighted Graph Theoretical Invariants." Digital Commons @ East Tennessee State University, 2017. https://dc.etsu.edu/etd/3248.
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To determine the function of a protein, we must know its 3-dimensional structure, which can be difficult to ascertain. Currently, predictive models are used to determine the structure of a protein from its sequence, but these models do not always predict the correct structure. To this end we use a nested graph model along with weighted invariants to minimize the errors and improve the accuracy of a predictive model to determine if we have the correct structure for a protein.
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Zarabi, Patrick, and August Denes. "Solving the Facility Location Problem using Graph Theory and Shortest Path Algorithms." Thesis, KTH, Optimeringslära och systemteori, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-229979.
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This thesis in systems engineering and optimization theory aims to solve a facility location problem within the context of a confined space with path and proximity constraints. The thesis was commissioned by LKAB Kiruna, to help in their decision of where to construct a new facility on their industrial premises. The facility location problem was divided into a main problem of finding the best position of the facility, and a sub-problem of how to model distances and feasible areas within this particular context. The distance and feasibility modeling was solved by utilizing graph theory to construct a graph representation of a geographic area and then obtain the necessary distances using Dijkstra’s shortest path algorithm. The main problem was then solved using a mixed integer linear programming formulation which utilizes the distances obtained through the Dijkstra algorithm. The model is also extended to not only decide the placement of one facility but to accommodate the placement of two facilities. The extended model was solved in three ways, a heuristic algorithm, a mixed integer non linear formulation and a mixed integer linear formulation. The results concluded that the implementation of the single facility model was able to obtain optimal solutions consistently. Regarding the extension, the mixed integer linear formulation was deemed to be the best model as it was computationally fast and consistently produced optimal solutions. Finally, several model improvements are identified to increase the applicability to different cases. These improvements could also allow the model to provide more strategical and managerial insights to the facility location decision process. Some future research into metaheuristics and machine learning are also suggested to further improve the usability of the models.Detta examensarbete inom systemteknik och optimeringslära syftar till att lösa ett lagerplaceringsproblem. Lagret ska ställas inom en liten yta med hänsyn till ruttbegränsningar och närhet till andra byggnader. Denna uppsats är begärd av LKAB Kiruna for att underlätta i deras beslut om var ett nytt lager skulle kunna byggas inom deras industriområde. Lagerplaceringsproblemet delades upp i två problem, huvudproblemet var att lokalisera den basta platsen för lagret att byggas. Subproblemet var hur distanser och tillåtna placeringar ska modelleras i denna specifika kontext med rutt- och narhetsbegränsningar. Distans- och platsmodelleringen gjordes genom att skapa en grafrepresentation av industriområdet. Sedan användes Dijkstras kortaste vägen algoritm för att erhålla alla distanser mellan möjliga byggområden och de produktionsanläggningar som behöver tillgång till lagret. Huvudproblemet kunde sedan lösas med hjälp av dessa distanser och en linjär heltalsoptimeringsmodell. Modellen utökades sedan för att tillåta placeringen av två separata lagerbyggnader. Den utökade modellen löstes med hjälp av tre olika implementeringar, en heuristisk algoritm, en ickelinjär heltalsoptimeringsmodell samt en linjär heltalsoptimeringsmodell. Resultaten visade att implementeringen av det ursprungliga lagerplaceringsproblemet konsekvent kunde beräkna optimala lösningar. Den utökade modellen löstes bäst av den linjära heltalsoptimeringsimplementeringen, då denna implementering konsekvent resulterade i bäst (lägst) värde i målfunktion samt löste problemet med låg beräkningstid. Slutligen identifierades flertalet potentiella modellförbättringar som skulle kunna implementeras för att ge modellen mer generaliserbarhet. Detta skulle även innebära att modellen själv kan utvärdera hur många lager som bör byggas givet en satt budget. Således kan modellen även erbjuda mer strategiska beslut om dessa förbättringar implementeras. Ytterligare forskning skulle även kunna göras inom metaheuristik och maskininlärning för att ytterligare förbättra distansmodelleringen.