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Applications of Graph Theory and Topology to Combinatorial DesignsSomporn Sutinuntopas 12 1900 (has links)
This dissertation is concerned with the existence and the isomorphism of designs. The first part studies the existence of designs. Chapter I shows how to obtain a design from a difference family. Chapters II to IV study the existence of an affine 3-(p^m,4,λ) design where the v-set is the Galois field GF(p^m). Associated to each prime p, this paper constructs a graph. If the graph has a 1-factor, then a difference family and hence an affine design exists. The question arises of how to determine when the graph has a 1-factor. It is not hard to see that the graph is connected and of even order. Tutte's theorem shows that if the graph is 2-connected and regular of degree three, then the graph has a 1-factor. By using the concept of quadratic reciprocity, this paper shows that if p Ξ 53 or 77 (mod 120), the graph is almost regular of degree three, i.e., every vertex has degree three, except two vertices each have degree tow. Adding an extra edge joining the two vertices with degree tow gives a regular graph of degree three. Also, Tutte proved that if A is an edge of the graph satisfying the above conditions, then it must have a 1-factor which contains A. The second part of the dissertation is concerned with determining if two designs are isomorphic. Here the v-set is any group G and translation by any element in G gives a design automorphism. Given a design B and its difference family D, two topological spaces, B and D, are constructed. We give topological conditions which imply that a design isomorphism is a group isomorphism.
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A collective field theory approach to the large N spectrum of two matricesCook, Martin 07 March 2008 (has links)
Abstract
The collective field theory technique provides a method of tackling problems with two N × N
matrices in the large N limit. The collective field background from one matrix is first found,
then the second matrix is introduced into this background as an impurity. Within the context
of the AdS/CFT correspondence, this technique can be used to describe gauge theory states in
the BMN limit.
This dissertation starts by developing the collective field theory technique, firstly in general
variables, then for one matrix, and subsequently for two matrices. It goes on to introduce a
Yang-Mills interaction term, where two variable identifications are considered. The first is the
more traditional angular momentum eigenstate model. The second is a model that directly uses
two of the Higgs scalars. This model has been mentioned in the literature, but has not been
considered in great depth. The exact two impurity spectrum is found, and the multi-impurity
spectrum is found to first order. The resulting energy values match a spectrum that has been
found for giant magnons.
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Column Profile Maps: A Tool for the Design and Analysis of Complex Distillation SystemsHolland, Simon Thornhill 31 October 2006 (has links)
Student Number : 9510423G
PhD Thesis
School of Chemical and Metallurgical Engineering
Faculty of Engineering and the Built Environment / Techniques for the design and analysis of simple column separations are well
established. Shortcut design techniques have been employed in the initial design of
these “traditional” distillation systems for a number of years and these columns are
well understood. However, few currently available techniques are useful in the
design of novel or complex configurations. The techniques that are available tend
to be configuration specific. An all inclusive or universal, design and analysis tool,
that can be applied to any and all configurations, is required.
Tapp et al (2004) introduced Column Profile Maps (CPMS) as a means of
addressing this issue. These are maps of composition profiles for column sections
with defined net-molar-flow and reflux ratio. It is suggested that by producing
CPMs for a configuration a designer can essentially superimpose these, determine
feasible operating profiles and hence column operating parameters.
In this thesis we show that this technique can be used to, not only produce quick
and easy complex column designs but gain a comprehensive understanding of the
steady-state operation of these arrangements. We demonstrate this analytical
potential first by application of the CPM technique to the two-product feed
distribution problem. It is shown that feed distribution can lower the minimum
required reflux ratio for non-sharp separations and in some cases produce feasible
separations from previously infeasible product specifications. A composition
region of operation for all distributed feed policies is also found.
The potential for detailed analysis, design and optimisation of complex
configurations is demonstrated via application of the CPM procedure to the fully
thermally coupled (Petlyuk) distillation column at both sharp and non-sharp split
conditions. A detailed design methodology for any configuration results from this.
It is found that the Petlyuk column can operate under five possible bulk/net flow
conditions and that very interesting and counter-intuitive net-molar-flows are
possible. A feasible column parameter region equivalent to the optimality region
(Halvorsen and Skogestad, 2001) is found for zeotropic systems. Importantly a
minimum reflux condition for the Petlyuk column is found. This condition can be
applied to all zeotropic systems for all product specifications. It is also
demonstrated that the CPM technique can be used for design optimisation of
separation systems.
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O problema de Kepler, uma solução coreográfica para o problema de três corpos e alguns resultados sobre configurações centrais / The Kepler\'s problem, a coreographic solution for the three body problem and some results about central configurations.Fernandes, Antonio Carlos 23 July 2009 (has links)
No presente trabalho apresentamos algumas soluçõesoes clássicas para o problema de dois e três corpos. Uma solução memorável para o problema de três corpos, na qual os corpos perfazem uma coreografia em forma de Oito, esta soluçãoo foi encontrada em 2000 por Montgomery e Chenciner. Por fim abordamos um pouco do problema clássico de n-Corpos e suas soluções particulares. / In this work we present some classical solutions for the Newtonian problem with two and three bodies. A remarkable solution for the three body problem, found by Montgomery and Chenciner, in which each body has an eight-shaped orbit is presented. Finally some particular solutions of the n-body problem and the so called central configurations, are presented and discussed.
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Construction of combinatorial designs with prescribed automorphism groupsUnknown Date (has links)
In this dissertation, we study some open problems concerning the existence or non-existence of some combinatorial designs. We give the construction or proof of non-existence of some Steiner systems, large sets of designs, and graph designs, with prescribed automorphism groups. / by Emre Kolotoæglu. / Thesis (Ph.D.)--Florida Atlantic University, 2013. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
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Low rank transitive representations, primitive extensions, and the collision problem in PSL (2, q)Unknown Date (has links)
Every transitive permutation representation of a finite group is the representation of the group in its action on the cosets of a particular subgroup of the group. The group has a certain rank for each of these representations. We first find almost all rank-3 and rank-4 transitive representations of the projective special linear group P SL(2, q) where q = pm and p is an odd prime. We also determine the rank of P SL (2, p) in terms of p on the cosets of particular given subgroups. We then investigate the construction of rank-3 transitive and primitive extensions of a simple group, such that the extension group formed is also simple. In the latter context we present a new, group theoretic construction of the famous Hoffman-Singleton graph as a rank-3 graph. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2015 / FAU Electronic Theses and Dissertations Collection
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Avaliação do comportamento cinemático de um mecanismo paralelo tridimensional. / Evaluation of kinematic performance of a tridimensional parallel mechanism.Malvezzi, Fernando 14 June 2006 (has links)
Este trabalho propõe uma nova estrutura cinemática paralela tridimensional com três graus de mobilidade que pode ser aplicada como robô manipulador. O volume do espaço de trabalho disponível é empregado como índice para avaliar o desempenho cinemático do mecanismo. As cinemáticas de posição e velocidade são desenvolvidas, tendo em vista o levantamento das configurações singulares e do espaço de trabalho. Os resultados obtidos com as cinemáticas direta e inversa são comparados de modo a verificar a correspondência entre eles. São levantadas diversas configurações singulares que correspondem ao alinhamento entre as barras das cadeias ativas do mecanismo e uma família de singularidades para uma das cadeias ativas é apresentada. O volume do espaço de trabalho do mecanismo é calculado pelo método da discretização, de modo a avaliar o volume do espaço de trabalho disponível, bem como a identificação da influência dos parâmetros dimensionais do mecanismo sobre este volume. O volume do espaço de trabalho com os parâmetros ótimos é expressivo, quando comparado com aqueles alcançados por manipuladores robóticos convencionais. / This dissertation proposes a novel three-degree-of-freedom parallel kinematic structure in order to be applied as a three-dimensional robot manipulator. The volume of the available workspace is employed as a performance index to evaluate the kinematic behavior of the mechanism. The position and velocity kinematics are developed for mapping singular configurations and evaluating the workspace. The results obtained by performing the direct and inverse kinematics are compared in order to verify the consistency between them. It is demonstrated that most of singular configurations is represented by the alignment of the links that belong to each active chain. In addition, a family of singularities for one of the active chains is presented. The volume of the workspace is calculated by using the discretization method not only for evaluating the feasible workspace but also for identifying the influence of dimensional parameters with respect to this volume. The achieved workspace by employing the optimal parameters is comparable to that reached by conventional robot manipulators.
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Two-dimensional horizontal (2DH) Boussinesq modelling of waves at the coastJudge, Frances Mary January 2018 (has links)
Understanding the behaviour of waves and their interaction with the coast is vital for marine engineers and maritime planners. As sea levels rise due to climate change, low-lying coastal areas and existing sea defences will become increasingly vulnerable to run-up and overtopping by large wave events. Accurate and effcient numerical models are essential tools for the assessment of such events and the impact they have on the coast so that effective coastal protection can be designed. This thesis presents a depth-integrated numerical solver with two horizontal dimensions for modelling waves in the coastal zone from intermediate depth to zero depth. Pre-breaking, the evolution of the water surface is calculated using the enhanced Boussinesq equation set of Madsen and Sorensen (1992). This equation set has improved dispersion characteristics over the classical Boussinesq equations, but with relatively few terms compared to models based on the Navier-Stokes equations, allowing for more effcient numerical modelling while maintaining suffcient accuracy. The equations are discretised using second-order finite differences and solved using the conjugate gradient method with fourth-order Runge-Kutta time stepping. Switching from the Boussinesq equation set to the shallow water equations allows shoaling waves to break, with the broken waves then propagating as bores. The shallow water equations are solved using a finite volume MUSCL-Hancock scheme with an HLLC approximate Riemann solver in order to resolve the behaviour of steep-fronted bores at the shore. The model incorporates a wetting and drying algorithm that models the moving wet/dry front. Waves are generated by a line of independently moving piston paddles, allowing full replication of laboratory experiments. A mapping technique is used in the region of the paddles to map the moving physical domain onto a fixed computational domain to facilitate the solution of the governing equations. Different aspects of the model are verified using standard benchmark tests. The complete model is then validated by comparing the numerical simulation of laboratory experiments with high quality experimental data from the UK Coastal Research Facility (UKCRF). The laboratory experiments simulated include the interaction of regular waves with sinusoidal and tri-cuspate beaches, and the interaction of both uni-directional and multi-directional focused wave groups with a plane beach. It is found that the model provides satisfactory wave phase resolution and reproduces most of the flow features of waves and currents in the shallow nearshore environment.
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Eu Tenho Trabalho, Eu Sou CidadÃo! ConsideraÃÃes acerca da CompreensÃo de Cidadania por Auxiliares de enfermagem da cidade de Fortaleza / I have work, I am citizen! considerations about the understanding of citizenship by the nursing assistants in Fortaleza cityÃtalo Emanuel Pinheiro de Lima 08 May 2008 (has links)
FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / Este trabalho aborda a compreensÃo de Cidadania explicitada por profissionai de nÃvel mÃdio (auxiliares de enfermagem) que trabalham em hospitais da cidade e Fortaleza. Trata-se de uma pesquisa empÃrica, onde, a partir do que estes profissionais relatam ser, para eles Cidadania, buscamos uma compreensao de como esse ideal à afetado pelas mudanÃas ocorridas no mundo do trabalho. / This work the explicit understanding of citizenship by mid-level professionals
(nurse) who work in hospitals of the city and Fortaleza. This is an empirical research, where,
from the report that these professionals be for them citizenship, we sought an understanding of
how that ideal is affected by changes in the world of work.
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Pardos livres em um campo de tensões: milícia, trabalho e poder (São Paulo, 1797-1831) / Free pardos in a field of tensions: militia, labor and power (São Paulo, 1797-1831)Souza, Fernando Prestes de 06 September 2017 (has links)
A tese versa sobre os milicianos pardos de São Paulo que atuaram no Regimento dos Úteis (1797-1831). As milícias de pardos e de pretos remontam ao século XVII e se caracterizaram como uma força militar fundamental para o Estado e um canal de expressão social e política para os seus integrantes até serem extintas, em 1831. Os problemas de que trata se desdobram em três eixos articulados entre si, a saber, a história militar, social e política. No primeiro deles, se examina a milícia parda em meio à estrutura militar colonial e à trajetória das milícias de cor luso-brasileiras. Ademais, aborda-se a sua estrutura de funcionamento e o seu papel nas atividades militares paulistas. O segundo eixo explora a origem e a condição social dos milicianos pardos, com destaque para as questões da formação do grupo de pardos livres e libertos, a vinculação dos milicianos a formas de trabalho compulsório e aos universos indígena, africano e mestiço, e a formação de famílias. Trata, igualmente, da condição socioeconômica dos milicianos, atentando para seu perfil ocupacional, níveis de riqueza e posse de escravos. Finalmente, o terceiro eixo considera a articulação da milícia com a política e encara o universo militar como um campo de tensões. Nele os problemas da oficialidade de cor e da existência dos seus corpos militares, fundamentais para a compreensão da atuação da milícia parda na conjuntura da independência em São Paulo, são examinados a partir das dimensões entrelaçadas do Estado, das autoridades militares locais, da competição entre oficiais brancos e pardos, e das relações de poder internas à milícia parda. A sociologia eliasiana constitui o principal referencial teórico e a tese se ampara em farta e diversificada documentação primária, com destaque para as listas nominativas, fontes paroquiais e especialmente os registros produzidos a partir das atividades cotidianas da milícia, tais como os requerimentos e o livro de matrícula dos milicianos pardos de São Paulo. / This doctoral thesis is about the Pardo militiamen of São Paulo who acted in the Regimento dos Úteis (1797-1831). That Pardo and Black militias dates back to the seventeenth century and were characterized as a fundamental military force for the State. Moreover, they were a sort of a canal of social and political expression for its members until they were extinguished in 1831. The problems in question unfold in three articulated issues: military, social and political history. In the first one, the Pardo militia is examined in the midst of the colonial military structure and the trajectory of the Luso-Brazilian militias. In addition, its operational structure and its role in the military activities of São Paulo are discussed. In the second one, it will be explored the origin of the Pardo and they social status as militiamen. This aspect emphasis the formation of the group of free and liberated Pardo, also the linking of militiamen to forms of compulsory labor and the Indigene, African and Mestizo universes, and formation of families. It also deals with the socioeconomic condition of the militiamen, considering their occupational profile, levels of wealth and the possession of slaves. Finally, the last aspect considers the articulation of the militia with politics and regards the military universe as a field of tensions. The problems of color officers and the existence of their military corps, which are fundamental to understanding the actions of the Free Colored militia in the context of independence in Sao Paulo, are examined from the intertwined dimensions of the State, the local military authorities, the competition between White and Free Colored officers, and from internal power relations to the brown militia. Eliasian sociology is the main theoretical reference, and the thesis is based on a large and diversified primary documentation, with special emphasis on the nominative lists, parish sources and especially the records produced from the daily activities of the militia, such as the requirements and the book of Registration of the Pardo militiamen of São Paulo.
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