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Articles 991 - 1020 of 3436

Full-Text Articles in Physical Sciences and Mathematics

Microfabrication With Smooth, Thin Cnt/Polymer Composite Sheets, Nathan Edward Boyer Jun 2016

Microfabrication With Smooth, Thin Cnt/Polymer Composite Sheets, Nathan Edward Boyer

Student Works

Carbon nanotube (CNT)/polymer composite sheets can be extremely high strength and lightweight, which makes them attractive for fabrication of mechanical structures. This thesis demonstrates a method whereby smooth, thin CNT/polymer composite sheets can be fabricated and patterned on the microscale using a process of photolithography and plasma etching. CNT/polymer composites were made from CNTs grown using chemical vapor deposition using supported catalyst growth and floating catalyst growth. The composite sheets had a roughness of approximately 30nm and were about 61¼m or 261¼m depending on whether they were made from supported catalyst grown or floating catalyst grown CNTs. The composites were …

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A Distributed Control Algorithm For Small Swarms In Cordon And Patrol, C Kristopher Alder Jun 2016

A Distributed Control Algorithm For Small Swarms In Cordon And Patrol, C Kristopher Alder

Student Works

Distributed teams of air and ground robots have the potential to be very useful in a variety of application domains, and much work is being done to design distributed algorithms that produce useful behaviors. This thesis presents a set of distributed algorithms that operate under minimal human input for patrol and cordon tasks. The algorithms allow the team to surround and travel between objects of interest. Empirical analyses indicate that the surrounding behaviors are robust to variations on the shape of the object of interest, communication loss, and robot failures.

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Criteria For Selecting Pegylation Sites On Proteins For Higher Thermodynamic Stability, Paul B. Lawrence Jun 2016

Criteria For Selecting Pegylation Sites On Proteins For Higher Thermodynamic Stability, Paul B. Lawrence

Theses and Dissertations

PEGylation of protein side-chains has been used for more than 30 years to enhance the pharmacokinetic properties of protein drugs, and has been enabled by the recent development of many chemoselective reactions for protein side-chain modification. However, there are no structure- or sequence-based guidelines for selecting sites that provide optimal PEG-based pharmacokinetic enhancement with minimal loss to biological activity. Chapter 1 is a brief introduction to protein PEGylation. In chapter 2 we use the WW domain of the human protein Pin 1 (WW) as a model system to probe the impact of PEG on protein conformational stability. Using a combination …

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American Spread Option Pricing With Stochastic Interest Rate, An Jiang Jun 2016

American Spread Option Pricing With Stochastic Interest Rate, An Jiang

Theses and Dissertations

In financial markets, spread option is a derivative security with two underlying assets and the payoff of the spread option depends on the difference of these assets. We consider American style spread option which allows the owners to exercise it at any time before the maturity. The complexity of pricing American spread option is that the boundary of the corresponding partial differential equation which determines the option price is unknown and the model for the underlying assets is two-dimensional.In this dissertation, we incorporate the stochasticity to the interest rate and assume that it satisfies the Vasicek model or the CIR …

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The Asynchronous T-Step Approximation For Scheduling Batch Flow Systems, David R. Grimsman Jun 2016

The Asynchronous T-Step Approximation For Scheduling Batch Flow Systems, David R. Grimsman

Theses and Dissertations

Heap models in the max-plus algebra are interesting dynamical systems that can be used to model a variety of tetris-like systems, such as batch flow shops for manufacturing models. Each heap in the model can be identified with a single product to manufacture. The objective is to manufacture a group of products in such an order so as to minimize the total manufacturing time. Because this scheduling problem reduces to a variation of the Traveling Salesman Problem (known to be NP-complete), the optimal solution is computationally infeasible for many real-world systems. Thus, a feasible approximation method is needed. This work …

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Weak Cayley Table Groups Of Wallpaper Groups, Rebeca Ann Paulsen Jun 2016

Weak Cayley Table Groups Of Wallpaper Groups, Rebeca Ann Paulsen

Theses and Dissertations

Let G be a group. A Weak Cayley Table mapping ϕ : G → G is a bijection such that ϕ(g1g2) is conjugate to ϕ(g1)ϕ(g2) for all g1, g2 in G. The set of all such mappings forms a group W(G) under composition. We study W(G) for the seventeen wallpaper groups G.

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Finding The First Stars, Eli D. Mcarthur Jun 2016

Finding The First Stars, Eli D. Mcarthur

Student Works

Minor perturbations resulting from a brief period of inflation at the time of the universe's birth seeded the growth of all structure in the universe. Using Enzo, a research code optimized for running cosmological simulations, we simulate the formation of the universe. We take into account the most current cosmological parameters and plot star formation rates of the universe for halos of varying mass from the beginning of time until today. By simulating star formation of the early universe, we verify that initially minuscule dark matter pockets resulting from inflationary perturbations attract more and more matter as the universe expands. …

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Spatial Trends And Facies Distribution Of The High-Energy Alluvial Cutler Formation, Southeastern Utah, Isaac John Allred Jun 2016

Spatial Trends And Facies Distribution Of The High-Energy Alluvial Cutler Formation, Southeastern Utah, Isaac John Allred

Theses and Dissertations

The Cutler Formation is composed of thick, arkosic, alluvial conglomerate, sandstone, and mudstone shed southwestward from the Uncompahgre Uplift into the Paradox Basin. More basin-ward the Cutler is recognized as a group consisting of differentiable formations. Discrete formations historically have not been distinguished near the uplift, but this study identified several separate successions in the Richardson Amphitheater. Research at the Richardson Amphitheater, ~12 km southwest of the uplift and ~30 km northeast of Moab, Utah, led to a systematic subdivision of the Permian Cutler Formation proximal to the uplift. Likely driven by channel cutting and migration across the alluvial fan, …

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Geochemistry Of The Fluorine- And Beryllium-Rich Spor Mountain Rhyolite, Western Utah, Shane Robert Dailey Jun 2016

Geochemistry Of The Fluorine- And Beryllium-Rich Spor Mountain Rhyolite, Western Utah, Shane Robert Dailey

Theses and Dissertations

The Miocene rhyolites of the Spor Mountain Formation hosts the world's largest beryllium deposit which produced 85% of the world's beryllium in 2010. The fresh lava is extremely enriched in Be (up to 75 ppm in matrix glass). We have examined the rhyolite to understand the Be enrichment. The Spor Mountain rhyolite contains ~40% quartz, ~40% sanidine, ~10% biotite, and ~10% plagioclase, along with accessory fluorite, columbite, euxenite, fergusonite, monazite, thorite, and zircon. Two types of rhyolite erupted within the Spor Mountain Formation, a less evolved magma (1150 ppm Rb, 42 ppm Be, 0.68 wt% F in matrix glass) and …

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Weakly Holomorphic Modular Forms In Prime Power Levels Of Genus Zero, David Joshua Thornton Jun 2016

Weakly Holomorphic Modular Forms In Prime Power Levels Of Genus Zero, David Joshua Thornton

Theses and Dissertations

Let N ∈ {8,9,16,25} and let M#0(N) be the space of level N weakly holomorphic modular functions with poles only at the cusp at infinity. We explicitly construct a canonical basis for M#0(N) indexed by the order of the pole at infinity and show that many of the coefficients of the elements of these bases are divisible by high powers of the prime dividing the level N. Additionally, we show that these basis elements satisfy an interesting duality property. We also give an argument that extends level 1 results …

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Glutamic Acid Resorcinarene-Based Molecules And Their Application In Developing New Stationary Phases In Ion Chromatography, Tayyebeh Panahi Jun 2016

Glutamic Acid Resorcinarene-Based Molecules And Their Application In Developing New Stationary Phases In Ion Chromatography, Tayyebeh Panahi

Theses and Dissertations

Resorcinarenes can be functionalized at their upper and lower rims. In this work, the upper rim of a resorcinarene was functionalized with glutamic acids and the lower rim was functionalized with either methyl or undecyl alkyl groups. The cavitands were characterized by nuclear magnetic resonance (NMR), mass spectrometry (MS), UV-vis spectroscopy, dynamic light scattering (DLS) and electron microscopy. The binding of resorcinarene with amine guests was studied in DMSO by UV-vis titration. The obtained binding constants (K values) were in the range of 12,000-136000 M-1. The resorcinarenes were shown to form aggregates in a variety of solvents. The aggregates were …

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A Distributed Control Algorithm For Small Swarms In Cordon And Patrol, C Kristopher Alder Jun 2016

A Distributed Control Algorithm For Small Swarms In Cordon And Patrol, C Kristopher Alder

Theses and Dissertations

Distributed teams of air and ground robots have the potential to be very useful in a variety of application domains, and much work is being done to design distributed algorithms that produce useful behaviors. This thesis presents a set of distributed algorithms that operate under minimal human input for patrol and cordon tasks. The algorithms allow the team to surround and travel between objects of interest. Empirical analyses indicate that the surrounding behaviors are robust to variations on the shape of the object of interest, communication loss, and robot failures.

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Schur Rings Over Projective Special Linear Groups, David R. Wagner Jun 2016

Schur Rings Over Projective Special Linear Groups, David R. Wagner

Theses and Dissertations

This thesis presents an introduction to Schur rings (S-rings) and their various properties. Special attention is given to S-rings that are commutative. A number of original results are proved, including a complete classification of the central S-rings over the simple groups PSL(2,q), where q is any prime power. A discussion is made of the counting of symmetric S-rings over cyclic groups of prime power order. An appendix is included that gives all S-rings over the symmetric group over 4 elements with basic structural properties, along with code that can be used, for groups of comparatively small order, to enumerate all …

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Using Perceptually Grounded Semantic Models To Autonomously Convey Meaning Through Visual Art, Derrall L. Heath Jun 2016

Using Perceptually Grounded Semantic Models To Autonomously Convey Meaning Through Visual Art, Derrall L. Heath

Theses and Dissertations

Developing advanced semantic models is important in building computational systems that can not only understand language but also convey ideas and concepts to others. Semantic models can allow a creative image-producing-agent to autonomously produce artifacts that communicate an intended meaning. This notion of communicating meaning through art is often considered a necessary part of eliciting an aesthetic experience in the viewer and can thus enhance the (perceived) creativity of the agent. Computational creativity, a subfield of artificial intelligence, deals with designing computational systems and algorithms that either automatically create original and functional products, or that augment the ability of humans …

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Existence Of A Periodic Brake Orbit In The Fully Symmetricplanar Four Body Problem, Ammon Si-Yuen Lam Jun 2016

Existence Of A Periodic Brake Orbit In The Fully Symmetricplanar Four Body Problem, Ammon Si-Yuen Lam

Theses and Dissertations

We investigate the existence of a symmetric singular periodic brake orbit in the equal mass, fully symmetric planar four body problem. Using regularized coordinates, we remove the singularity of binary collision for each symmetric pair. We use topological and symmetry tools in our investigation.

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Sedimentology And Stratigraphy Of The Middle Jurassic Preuss Sandstonein Northern Utah And Eastern Idaho, Preston Scott Cook Jun 2016

Sedimentology And Stratigraphy Of The Middle Jurassic Preuss Sandstonein Northern Utah And Eastern Idaho, Preston Scott Cook

Theses and Dissertations

The purpose of this study is to analyze the sedimentology and stratigraphy of the Middle Jurassic Preuss Sandstone and re-evaluate past sedimentological interpretations. The Preuss is located in northern Utah, western Wyoming and eastern Idaho and is stratigraphically equivalent to the Entrada Sandstone, which is Callovian in age (Dossett et al., 2014). This study is the first attempt at 1) a sequence stratigraphic framework, 2) a petroleum system analysis and 3) an extraterrestrial analog study for the Preuss. This study frames the Preuss within three broad facies groups: marine, coastal and terrestrial. The marine group includes the open marine and …

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Microfabrication With Smooth, Thin Cnt/Polymer Composite Sheets, Nathan Edward Boyer Jun 2016

Microfabrication With Smooth, Thin Cnt/Polymer Composite Sheets, Nathan Edward Boyer

Theses and Dissertations

Carbon nanotube (CNT)/polymer composite sheets can be extremely high strength and lightweight, which makes them attractive for fabrication of mechanical structures. This thesis demonstrates a method whereby smooth, thin CNT/polymer composite sheets can be fabricated and patterned on the microscale using a process of photolithography and plasma etching. CNT/polymer composites were made from CNTs grown using chemical vapor deposition using supported catalyst growth and floating catalyst growth. The composite sheets had a roughness of approximately 30nm and were about 61¼m or 261¼m depending on whether they were made from supported catalyst grown or floating catalyst grown CNTs. The composites were …

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In Situ Magnetic Field Characterization With The Directional Hanle Effect, Jarom Silver Jackson Jun 2016

In Situ Magnetic Field Characterization With The Directional Hanle Effect, Jarom Silver Jackson

Theses and Dissertations

We present a novel method of in situ magnetic field mapping related to the Hanle effect. This method uses the change in spatial radiation pattern of scattered light, which we call a 'directional Hanle effect,' rather than the loss of polarization more commonly associated with the Hanle effect. It is particularly well suited for fields in a magneto-optical trap (MOT), requiring only the addition of a narrow slit and a camera to typical MOT components. The use of this method is demonstrated by measuring the gradient through, and location of, the zero-point of the field in our strontium MOT.

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Analyses Of Mrna Cleavage By Rele And The Role Of Trna Methyltransferase Trmd Using Bacterial Ribosome Profiling, Jae Yeon Hwang Jun 2016

Analyses Of Mrna Cleavage By Rele And The Role Of Trna Methyltransferase Trmd Using Bacterial Ribosome Profiling, Jae Yeon Hwang

Theses and Dissertations

Protein synthesis is a fundamental and ultimate process in living cells. Cells possess sophisticated machineries and continuously carry out complex processes. Monitoring protein synthesis in living cells not only inform us about the mechanism of translation but also deepen our insights about all aspects of life. Understanding the structure and mechanism of the ribosome and its associated factors helped us enlarge our knowledge on protein synthesis. Recently, with the dramatic advances of high-throughput sequencing and bioinformatics, a new technique called ribosome profiling emerged. By retrieving mRNA fragments protected by translating ribosomes, ribosome profiling reveals global ribosome occupancy along mRNAs in …

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Machine Learning For Disease Prediction, Abraham Jacob Frandsen Jun 2016

Machine Learning For Disease Prediction, Abraham Jacob Frandsen

Theses and Dissertations

Millions of people in the United States alone suffer from undiagnosed or late-diagnosed chronic diseases such as Chronic Kidney Disease and Type II Diabetes. Catching these diseases earlier facilitates preventive healthcare interventions, which in turn can lead to tremendous cost savings and improved health outcomes. We develop algorithms for predicting disease occurrence by drawing from ideas and techniques in the field of machine learning. We explore standard classification methods such as logistic regression and random forest, as well as more sophisticated sequence models, including recurrent neural networks. We focus especially on the use of medical code data for disease prediction, …

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Designing An Instructional Publication On The Geology Of Capitol Reef National Park, Kinsey Gayle Spiel Jun 2016

Designing An Instructional Publication On The Geology Of Capitol Reef National Park, Kinsey Gayle Spiel

Theses and Dissertations

The wide variety of strata, structural features, and landscapes of Capitol Reef National Park result from its complex, yet discoverable history. Our task was to write and design an informative book on this complexity while making it engaging for the public. We approached the design of this book using Stufflebeam's (2007) CIPP model. The CIPP model uses both summative and formative evaluations in the categories of context, input, process, and product. It provides the framework to methodically investigate the value of a product and identify and correct less effective pedagogical and design elements during its development. We demonstrated the use …

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Periodic Points And Surfaces Given By Trace Maps, Kevin Gregory Johnston Jun 2016

Periodic Points And Surfaces Given By Trace Maps, Kevin Gregory Johnston

Theses and Dissertations

In this thesis, we consider the properties of diffeomorphisms of R3 called trace maps. We begin by introducing the definition of the trace map. The group B3 acts by trace maps on R3. The first two chapters deal with the action of a specific element of B3,called αn. In particular, we study the fixed points of αn lying on a topological subspace contained in R3, called T . We investigate the duality of the fixed points of the action ofαn, which will be defined later in the thesis.Chapter 3 involves the study of the fixed points of an element called …

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Role For Reactive Oxygen Species In Methamphetamine Modulation Of Dopamine Release In The Striatum, David Matthew Hedges May 2016

Role For Reactive Oxygen Species In Methamphetamine Modulation Of Dopamine Release In The Striatum, David Matthew Hedges

Theses and Dissertations

Methamphetamine (METH) is a highly addictive substance that is highly prevalent in today’s society, with over 1 in 20 adults over 26 having taken it at least once. While it is known that METH, a common psychostimulant, acts on both the mesolimbic dopamine (DA) and nigrostriatal DA systems by affecting proteins involved in DA reuptake and vesicular packaging, the specific mechanism of what is known as METH neurotoxicity remains obscure, but has been shown to involve oxidative stress. Studies have shown that reactive oxygen species act on the same proteins that METH affects. Oxidative species have also been known to …

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Barriers To Initiation Of Open Source Software Projects In Research Libraries, Jason Curtis Thacker May 2016

Barriers To Initiation Of Open Source Software Projects In Research Libraries, Jason Curtis Thacker

Theses and Dissertations

Libraries share a number of core values with the Open Source Software (OSS) movement, suggesting there should be a natural tendency toward library participation in OSS projects. However, Dale Askey's 2008 Code4Lib column entitled We Love Open Source Software. No, You Can't Have Our Code, claims that while libraries are strong proponents of OSS, they are unlikely to actually contribute to OSS projects. He identifies, but does not empirically substantiate, six barriers that he believes contribute to this apparent inconsistency. The goal of this thesis is to empirically investigate not only Askey's central claim but also the six barriers he …

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Intelligent Pen: A Least Cost Search Approach To Stroke Extraction In Historical Documents, Kevin L. Bauer May 2016

Intelligent Pen: A Least Cost Search Approach To Stroke Extraction In Historical Documents, Kevin L. Bauer

Theses and Dissertations

Extracting strokes from handwriting in historical documents provides high-level features for the challenging problem of handwriting recognition. Such handwriting often contains noise, faint or incomplete strokes, strokes with gaps, overlapping ascenders and descenders and competing lines when embedded in a table or form, making it unsuitable for local line following algorithms or associated binarization schemes. We introduce Intelligent Pen for piece-wise optimal stroke extraction. Extracted strokes are stitched together to provide a complete trace of the handwriting. Intelligent Pen formulates stroke extraction as a set of piece-wise optimal paths, extracted and assembled in cost order. As such, Intelligent Pen is …

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An Analyzer For Message Passing Programs, Yu Huang May 2016

An Analyzer For Message Passing Programs, Yu Huang

Theses and Dissertations

Asynchronous message passing systems are fast becoming a common means for communication between devices. Two problems existing in message passing programs are difficult to solve. The first problem, intended or otherwise, is message-race where a receive may match with more than one send in the runtime system. This non-determinism often leads to intermittent and unexpected behavior depending on the resolution of the race. Another problem is deadlock, which is a situation in that each member process of the group is waiting for some member process to communicate with it, but no member is attempting to communicate with it. Detecting if …

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Graphical Narrative Interfaces: Representing Spatiotemporal Information For A Human-Robot Team With A Highly Autonomous Robot, Hiroaki Nakano May 2016

Graphical Narrative Interfaces: Representing Spatiotemporal Information For A Human-Robot Team With A Highly Autonomous Robot, Hiroaki Nakano

Theses and Dissertations

Having a well-developed Graphical User Interface (GUI) is often necessary for a human-robot team, especially when the human and the robot are not in close proximity to each other or when the human does not interact with the robot in real time. Most current GUIs process and display information in real time, but the time to interact with these systems does not scale well when the complexity of the displayed information increases or when information must be fused to support decision-making. We propose a new interface concept, a Graphical Narrative Interface (GNI), which presents story-based summaries driven by accumulated data. …

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Placental ‘€˜Omics’€™ Study To Understand The Pathogenesis Of Preeclampsia, Komal Kedia May 2016

Placental ‘€˜Omics’€™ Study To Understand The Pathogenesis Of Preeclampsia, Komal Kedia

Theses and Dissertations

Preeclampsia (PE) is a potentially fatal complication of pregnancy characterized by an increase in blood pressure (>140/90 mmHg) and proteinuria (>300 mg/24 hrs), often accompanied by edema. Symptoms of PE start after 20 weeks of gestation. If PE remains untreated, it can lead to eclampsia, grand-mal seizures responsible for most fatalities. PE is believed to affect 2-10% of pregnancies worldwide, and claims the lives of over 75,000 mothers and 500,000 newborns yearly. No therapeutic agents have been developed to prevent or cure PE. Part of the reason for this is the absence of a complete understanding of the …

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Confirm: Clustering Of Noisy Form Images Using Robust Matching, Christopher Alan Tensmeyer May 2016

Confirm: Clustering Of Noisy Form Images Using Robust Matching, Christopher Alan Tensmeyer

Theses and Dissertations

Identifying the type of a scanned form greatly facilitates processing, including automated field segmentation and field recognition. Contrary to the majority of existing techniques, we focus on unsupervised type identification, where the set of form types are not known apriori, and on noisy collections that contain very similar document types. This work presents a novel algorithm: CONFIRM (Clustering Of Noisy Form Images using Robust Matching), which simultaneously discovers the types in a collection of forms and assigns each form to a type. CONFIRM matches type-set text and rule lines between forms to create domain specific features, which we show outperform …

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Isomorphisms Of Landau-Ginzburg B-Models, Nathan James Cordner May 2016

Isomorphisms Of Landau-Ginzburg B-Models, Nathan James Cordner

Theses and Dissertations

Landau-Ginzburg mirror symmetry predicts isomorphisms between graded Frobenius algebras (denoted A and B) that are constructed from a nondegenerate quasihomogeneous polynomial W and a related group of symmetries G. In 2013, Tay proved that given two polynomials W1, W2 with the same quasihomogeneous weights and same group G, the corresponding A-models built with (W1, G) and (W2, G) are isomorphic. An analogous theorem for isomorphisms between orbifolded B-models remains to be found. This thesis investigates isomorphisms between B-models using polynomials in two variables in search of such a theorem. In particular, several examples are given showing the relationship between continuous …

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