Browsing Combinatorics and Optimization by Title
Now showing items 408-427 of 434
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Techniques for Proving Approximation Ratios in Scheduling
(University of Waterloo, 2010-09-30)The problem of finding a schedule with the lowest makespan in the class of all flowtime-optimal schedules for parallel identical machines is an NP-hard problem. Several approximation algorithms have been suggested for ... -
Techniques of Side Channel Cryptanalysis
(University of Waterloo, 2001)The traditional model of cryptography examines the security of cryptographic primitives as mathematical functions. This approach does not account for the physical side effects of using these primitives in the real world. ... -
Technology Diffusion on Spiders
(University of Waterloo, 2017-08-29)There has been significant research about cascade effects that occur when information is spread through a network. Most models of such cascade effects are highly-localised, which means that they assume a node’s behaviour ... -
Theory of measurement-based quantum computing
(University of Waterloo, 2008-12-10)In the study of quantum computation, data is represented in terms of linear operators which form a generalized model of probability, and computations are most commonly described as products of unitary transformations, which ... -
Thin Trees in Some Families of Graphs
(University of Waterloo, 2018-04-25)Let 𝐺=(𝑉,𝐸) be a graph and let 𝑇 be a spanning tree of 𝐺. The thinness parameter of 𝑇 denoted by 𝜌(𝑇) is the maximum over all cuts of the proportion of the edges of 𝑇 in the cut. Thin trees play an important role ... -
Thomassen’s 5-Choosability Theorem Extends to Many Faces
(University of Waterloo, 2021-09-10)We prove in this thesis that planar graphs can be L-colored, where L is a list-assignment in which every vertex has a 5-list except for a collection of arbitrarily large faces which have 3-lists, as long as those faces ... -
Tolls For Atomic Congestion Games
(University of Waterloo, 2021-02-26)In games where selfish players compete for resources, they often arrive at equilibria that are less desirable than the social optimum. To combat this inefficiency, it is common for some central authority to place tolls on ... -
Towards Erdős-Hajnal for Graphs with No 5-Hole
(Springer Nature, 2019-11-01)The Erdős-Hajnal conjecture says that for every graph H there exists c > 0 such that max(α(G), w(G)) ≥ nc for every H-free graph G with n vertices, and this is still open when H = C5. Until now the best bound known on ... -
Towards Private Biometric Authentication and Identification
(University of Waterloo, 2023-09-05)Handwriting and speech are important parts of our everyday lives. Handwriting recognition is the task that allows the recognizing of written text, whether it be letters, words or equations, from given data. When analyzing ... -
Transitive Factorizations of Permutations and Eulerian Maps in the Plane
(University of Waterloo, 2005)The problem of counting ramified covers of a Riemann surface up to homeomorphism was proposed by Hurwitz in the late 1800's. This problem translates combinatorially into factoring a permutation with a specified cycle ... -
Transmitting Quantum Information Reliably across Various Quantum Channels
(University of Waterloo, 2013-05-01)Transmitting quantum information across quantum channels is an important task. However quantum information is delicate, and is easily corrupted. We address the task of protecting quantum information from an information ... -
Transversal Problems In Sparse Graphs
(University of Waterloo, 2022-09-20)Graph transversals are a classical branch of graph algorithms. In such a problem, one seeks a minimum-weight subset of nodes in a node-weighted graph $G$ which intersects all copies of subgraphs~$F$ from a fixed family ... -
The Traveling Tournament Problem
(University of Waterloo, 2022-08-17)In this thesis we study the Traveling Tournament problem (TTP) which asks to generate a feasible schedule for a sports league such that the total travel distance incurred by all teams throughout the season is minimized. ... -
Triangle-free graphs that do not contain an induced subdivision of K4 are 3-colorable
(Wiley, 2019-10)We show that triangle-free graphs that do not contain an induced subgraph isomorphic to a subdivision of K4 are 3-colorable. This proves a conjecture of Trotignon and Vušković. -
Triangle-free graphs with no six-vertex induced path
(Elsevier, 2018-08)The graphs with no five-vertex induced path are still not understood. But in the triangle-free case, we can do this and one better; we give an explicit construction for all triangle-free graphs with no six-vertex induced ... -
Two combinatorial problems from craniosynostosis
(University of Waterloo, 2022-09-08)The art of cranial vault remodelling surgery is amazing and fascinating, but remains much of that, an art, to this day. In this thesis, we provide two mathematical approaches to tackle cranial vault remodelling surgery, ... -
Unavoidable Minors of Large 5-Connected Graphs
(University of Waterloo, 2016-08-24)This thesis shows that, for every positive integer $n \geq 5$, there exists a positive integer $N$ such that every $5-$connected graph with at least $N$ vertices has a minor isomorphic to one of thirty explicitly defined ... -
Uniform Generation of Graphical Realizations of Joint Degree Matrices
(University of Waterloo, 2023-09-21)In this thesis, we introduce JDM_GEN, an algorithm designed to uniformly generate graphical realizations of a given joint degree matrix. Amanatidis and Kleer previously employed an MCMC-based method to address this ... -
Uniform Mixing of Quantum Walks and Association Schemes
(University of Waterloo, 2013-09-26)In recent years quantum algorithms have become a popular area of mathematical research. Farhi and Gutmann introduced the concept of a quantum walk in 1998. In this thesis we investigate mixing properties of continuous-time ... -
Uniform Mixing on Cayley Graphs over Z_3^d
(University of Waterloo, 2014-05-22)This thesis investigates uniform mixing on Cayley graphs over Z_3^d. We apply Mullin's results on Hamming quotients, and characterize the 2(d+2)-regular connected Cayley graphs over Z_3^d that admit uniform mixing at time ...