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Ventura, Ivan. "Radial Solutions to an Elliptic Boundary Valued Problem." Scholarship @ Claremont, 2007. https://scholarship.claremont.edu/hmc_theses/203.
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In this paper we prove that div(|x|β∇u)+|x|αf(u)=0, inB u = 0 on ∂B has infinitely many solutions when f is superlinear and grows subcritically for u ≥ 0 and up to critically for u less than 0 with 10, 13 N+β−2 N+β−2 We make extensive use of Pohozaev identities and phase plane and energy arguments.
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Meng, Tan Chee. "Infinitely Many Radial Solutions to a Superlinear Dirichlet Problem." Scholarship @ Claremont, 2007. https://scholarship.claremont.edu/hmc_theses/202.
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My thesis work started in the summer of 2005 as a three way joint project by Professor Castro and Mr. John Kwon and myself. A paper from this joint project was written and the content now forms my thesis.
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Sahin, Ferat. "A Radial Basis Function Approach to a Color Image Classification Problem in a Real Time Industrial Application." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36847.
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In this thesis, we introduce a radial basis function network approach to solve a color image classification problem in a real time industrial application. Radial basis function networks are employed to classify the images of finished wooden parts in terms of their color and species. Other classification methods are also examined in this work. The minimum distance classifiers are presented since they have been employed by the previous research.
We give brief definitions about color space, color texture, color quantization, color classification methods. We also give an intensive review of radial basis functions, regularization theory, regularized radial basis function networks, and generalized radial basis function networks. The centers of the radial basis functions are calculated by the k-means clustering algorithm. We examine the k-means algorithm in terms of starting criteria, the movement rule, and the updating rule. The dilations of the radial basis functions are calculated using a statistical method.
Learning classifier systems are also employed to solve the same classification problem. Learning classifier systems learn the training samples completely whereas they are not successful to classify the test samples. Finally, we present some simulation results for both radial basis function network method and learning classifier systems method. A comparison is given between the results of each method. The results show that the best classification method examined in this work is the radial basis function network method.Master of Science
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Kurepa, Alexandra. "Radially Symmetric Solutions to a Superlinear Dirichlet Problem in a Ball." Thesis, North Texas State University, 1987. https://digital.library.unt.edu/ark:/67531/metadc330725/.
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Puerta, Gabriel Figueiredo. "Restauração de sistemas de distribuição radiais quando existe um número reduzido de chaves de manobra." Ilha Solteira, 2018. http://hdl.handle.net/11449/158269.
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Orientador: Rubén Augusto Romero LázaroResumo: Neste trabalho, apresenta-se um modelo matemático especializado para a otimização do problema da restauração de redes de distribuição de energia elétrica radiais quando existem poucas chaves manobráveis. A existência de um número reduzido de chaves seccionadoras na rede de distribuição é uma característica típica de sistemas reais. O problema da restauração de redes de distribuição consiste em obter um plano de restauração que restabeleça o máximo possível de cargas presentes na parcela do sistema que foi desenergizada após a ocorrência de uma falta permanente. O plano de restauração deve ser obtido o mais rápido possível. O modelo matemático proposto possui como objetivo maximizar o restabelecimento de energia àqueles setores de carga que estão desenergizados e minimizar o número total de chaveamentos necessários para que a restauração aconteça. O modelo matemático resultante é de programação cônica de segunda ordem inteira mista e é resolvido através de solucionadores comerciais que se baseiam em técnicas de otimização clássicas. Os testes considerando faltas permanentes foram simulados em sistemas de distribuição testes de 53 e 84 barras. Os sistemas foram adaptados e transportados para a problemática do trabalho e os resultados adquiridos qualificam a robustez e a eficácia do modelo matemático especializado proposto para a resolução do problema.
Abstract: This work proposes an specialized mathematical model for the optimization of the restoration problem in radial electric power distribution systems with few manageable switches. The existence of a reduced number of switches in the distribution systems it’s a typical characteristic of real systems. The restoration problem in radial electric power distribution systems is to obtain a restoration plan that reestablishes the maximum amount of present loads in the system portion that has been de-energized after the occurrence of a permanent fault. The elaboration of the restoration plan must be as soon as possible. The proposed mathematical model aims at maximizing the power re-establishment to the de-energized load sectors and at minimizing the total amount of operated switches that are required for the restoration happen. The resulting mathematical model is a mixed-integer second-order conic programming problem and it’s solved through commercial solves that use classical optimization techniques as base. The tests considering permanents faults were simulated in 84 and 53-bus distribution systems. The systems were adapted and transported to the work’s problematic and the acquired results show the robustness and the effectiveness of the proposed specialized mathematical model for the problem resolution.
Mestre
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Al-Bayati, Salam Adel. "Boundary element analysis for convection-diffusion-reaction problems combining dual reciprocity and radial integration methods." Thesis, Brunel University, 2018. http://bura.brunel.ac.uk/handle/2438/17071.
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In this research project, the Boundary Element Method (BEM) is developed and formulated for the solution of two-dimensional convection-diffusion-reaction problems. A combined approach with the dual reciprocity boundary element method (DRBEM) has been applied to solve steady-state problems with variable velocity and transient problems with constant and variable velocity fields. Further, the radial integration boundary element method (RIBEM) is utilised to handle non-homogeneous problems with variable source term. For all cases, a boundary-only formulation is produced. Initially, the steady-state case with constant velocity is considered, by employing constant boundary elements and a fundamental solution of the adjoint equation. This fundamental solution leads to a singular integral equation. The conservation laws, usually applied to avoid this integration, do not hold when a chemical reaction is taking place. Then, the integrals are successfully computed using Telles' technique. The application of the BEM for this particular equation is discussed in detail in this work. Next, the steady-state problem for variable velocity fields is presented and investigated. The velocity field is divided into an average value plus a perturbation. The perturbation is taken to the right-hand-side of the equation generating a non-homogeneous term. This nonhomogeneous equation is treated by utilising the DRM approach resulting in a boundary-only equation. Then, an integral equation formulation for the transient problem with constant velocity is derived, based on the DRM approach utilising the fundamental solution of the steady-state case. Therefore, the convective terms will be encompassed by the fundamental solution and lie within the boundary integral after application of Greens's second identity, leaving on the right-hand-side of the equation a domain integral involving the time-derivative only. The proposed DRM method needs the time-derivative to be expanded as a series of functions that will allow the domain integral to be moved to the boundary. The expansion required by the DRM uses functions which take into account the geometry and physics of the problem, if velocity-dependent terms are used. After that, a novel DRBEM model for transient convection-diffusion-reaction problems with variable velocity field is investigated and validated. The fundamental solution for the corresponding steady-state problem is adopted in this formulation. The variable velocity is decomposed into an average which is included into the fundamental solution of the corresponding equation with constant coefficients, and a perturbation which is treated using the DRM approximation. The mathematical formulation permits the numerical solution to be represented in terms of boundary-only integrals. Finally, a new formulation for non-homogeneous convection-diffusion-reaction problems with variable source term is achieved using RIBEM. The RIM is adopted to convert the domain integrals into boundary-only integrals. The proposed technique shows very good solution behaviour and accuracy in all cases studied. The convergence of the methods has been examined by implementing different error norm indicators and increasing the number of boundary elements in all cases. Numerical test cases are presented throughout this research work. Their results are sufficiently encouraging to recommend the use of the techniques developed for solution of general convection-diffusion-reaction problems. All the simulated solutions for several examples showed very good agreement with available analytical solutions, with no numerical problems of oscillation and damping of sharp fronts.
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Cardona, Natalia Patiño [UNESP]. "Reconfiguração de sistemas de distribuição de energia elétrica utilizando uma metodologia multipartida." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/136281.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Este trabalho apresenta uma proposta baseada na metodologia multipartida para a resolução do Problema de Reconfiguração de Sistemas de Distribuição de Energia Elétrica, de natureza combinatória e modelado como um problema de Programação Não Linear Inteiro Misto. O objetivo principal deste trabalho é encontrar a topologia radial ótima para minimizar as perdas ativas dos sistemas de distribuição, e para isso é preciso, primeiramente, a resolução de um problema de fluxo de potência para sistemas fracamente malhados onde é calculada a potência aparente do sistema, a qual vai ser utilizada pelo algoritmo de Prim como o peso para a geração das soluções iniciais radiais de boa qualidade. Para implementar a metodologia proposta deve-se desenvolver também um algoritmo de fluxo de potência radial, utilizado para calcular tanto as perdas ativas do sistema (função objetivo do problema), como para verificar a factibilidade das propostas de solução. Nesta primeira etapa é feita uma variação aleatória dos pesos dos ramos, e são resolvidos tantos problemas de fluxo de potência radial quanto soluções aleatórias obtidas, para encontrar soluções de boa qualidade próximas ao ótimo. Finalmente, é feita uma busca local através da troca de ramos como tentativa para encontrar a solução ótima. As soluções obtidas pela metodologia proposta são obtidas através da programação de algoritmos implementados em linguagem C++. Os resultados obtidos mostram a eficiência da aplicação da metodologia, estes resultados foram comparados com os existentes na literatura e os obtidos pela resolução de um modelo de otimização resolvido com o solver comercial CPLEX.
This work presents a proposal based on multi-start methodology for the solution of the distribution network reconfiguration problem, of combinatorial nature and modeled as a mixed-integer nonlinear programming problem. The main objective of this work is to find the optimal radial topology to minimize active power losses in distribution systems. This requires, at first, the resolution of a power flow problem for weakly meshed systems where the apparent power of the system is calculated, which will be used by the Prim algorithm as the weight for generating the radial initial good quality solution. To implement the proposed methodology is also developed a radial power flow algorithm, used to calculate both the active system losses (objective function of the problem) and to verify the feasibility of the proposed solutions. In this first stage is made a random variation of the weights of branches, and there are solved as many radial power flows as random solutions obtained, to find good quality solutions close to optimal. Finally, a local search is made by doing an exchange of branches as an attempt to find the optimal solution. The solutions obtained by the proposed method are acquired by programming algorithms implemented in C ++ language. The results show the effectiveness of the application of the methodology. These results were compared with those in the literature and those obtained by solving an optimization model solved by the commercial solver CPLEX.
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Cardona, Natalia Patiño. "Reconfiguração de sistemas de distribuição de energia elétrica utilizando uma metodologia multipartida /." Ilha Solteira, 2016. http://hdl.handle.net/11449/136281.
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Orientador: Rubén Augusto Romero LázaroResumo: Este trabalho apresenta uma proposta baseada na metodologia multipartida para a resolução do Problema de Reconfiguração de Sistemas de Distribuição de Energia Elétrica, de natureza combinatória e modelado como um problema de Programação Não Linear Inteiro Misto. O objetivo principal deste trabalho é encontrar a topologia radial ótima para minimizar as perdas ativas dos sistemas de distribuição, e para isso é preciso, primeiramente, a resolução de um problema de fluxo de potência para sistemas fracamente malhados onde é calculada a potência aparente do sistema, a qual vai ser utilizada pelo algoritmo de Prim como o peso para a geração das soluções iniciais radiais de boa qualidade. Para implementar a metodologia proposta deve-se desenvolver também um algoritmo de fluxo de potência radial, utilizado para calcular tanto as perdas ativas do sistema (função objetivo do problema), como para verificar a factibilidade das propostas de solução. Nesta primeira etapa é feita uma variação aleatória dos pesos dos ramos, e são resolvidos tantos problemas de fluxo de potência radial quanto soluções aleatórias obtidas, para encontrar soluções de boa qualidade próximas ao ótimo. Finalmente, é feita uma busca local através da troca de ramos como tentativa para encontrar a solução ótima. As soluções obtidas pela metodologia proposta são obtidas através da programação de algoritmos implementados em linguagem C++. Os resultados obtidos mostram a eficiência da aplicação da metodologia, estes resul... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: This work presents a proposal based on multi-start methodology for the solution of the distribution network reconfiguration problem, of combinatorial nature and modeled as a mixed-integer nonlinear programming problem. The main objective of this work is to find the optimal radial topology to minimize active power losses in distribution systems. This requires, at first, the resolution of a power flow problem for weakly meshed systems where the apparent power of the system is calculated, which will be used by the Prim algorithm as the weight for generating the radial initial good quality solution. To implement the proposed methodology is also developed a radial power flow algorithm, used to calculate both the active system losses (objective function of the problem) and to verify the feasibility of the proposed solutions. In this first stage is made a random variation of the weights of branches, and there are solved as many radial power flows as random solutions obtained, to find good quality solutions close to optimal. Finally, a local search is made by doing an exchange of branches as an attempt to find the optimal solution. The solutions obtained by the proposed method are acquired by programming algorithms implemented in C ++ language. The results show the effectiveness of the application of the methodology. These results were compared with those in the literature and those obtained by solving an optimization model solved by the commercial solver CPLEX.
Mestre
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Sargent, Ethan. "Radial Solutions to Semipositone Dirichlet Problems." Scholarship @ Claremont, 2019. https://scholarship.claremont.edu/hmc_theses/229.
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We study a Dirichlet problem, investigating existence and uniqueness for semipositone and superlinear nonlinearities. We make use of Pohozaev identities, energy arguments, and bifurcation from a simple eigenvalue.
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Sfecci, Andrea. "Some existence results for boundary value problems : a promenade along resonance." Doctoral thesis, SISSA, 2012. http://hdl.handle.net/20.500.11767/4703.
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I present many existence result to many boundary value problems, in particular periodic problems and Neumann elliptic problems. The results use the method of the topological degree theory. In the thesis different problems are treated: planar systems, systems with a singularity, impact oscillators, coupled oscillators and radial elliptic problems.
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Yildirim, Okan. "Radial Point Interpolation Method For Plane Elasticity Problems." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612537/index.pdf.
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Meshfree methods have become strong alternatives to conventional numerical methods used in solid mechanics after significant progress in recent years. Radial point interpolation method (RPIM) is a meshfree method based on Galerkin formulation and constructs shape functions which enable easy imposition of essential boundary conditions. This thesis analyses plane elasticity problems using RPIM. A computer code implementing RPIM for the solution of plane elasticity problems is developed. Selected problems are solved and the effect of shape parameters on the accuracy of RPIM with and without polynomial terms added in the interpolation is studied. The optimal shape parameters are determined for plane elasticity problems.
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La, Delfa Patricio. "Contribution à la conception silencieuse par démarches directe et inverse de machines synchrones à aimants permanents et bobinage dentaire." Thesis, Ecole centrale de Lille, 2017. http://www.theses.fr/2017ECLI0036/document.
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Cette thèse porte sur la conception silencieuse par démarches inverses de machines synchrones à aimants permanents dotées de bobinages dentaires. Notre travail se focalise sur l’analyse des raies de forces radiales à l’origine du bruit magnétique. En premier lieu, un modèle direct électromagnétique, nous a permis de déterminer le spectre spatio-temporel de la force radiale dans l’entrefer. Ce dernier nous offre la possibilité d’obtenir pas à pas et de manière analytique l’induction radiale dans l’entrefer, résultat du produit de la force magnétomotrice totale et de la perméance d’entrefer globale. Plusieurs machines dotées d’un bobinage dentaire et distribué ont été évaluées, comparées à des simulations par éléments finis et corroborés par une analyse modale opérationnelle sur un prototype existant au laboratoire. Puis la démarche inverse de conception est abordée par le biais de deux outils « analytiques prédictifs » donnant les origines des ordres faibles spatio-temporels de la force radiale dans l’entrefer. Enfin, la résolution du problème inverse est conduite au moyen d’une boucle itérative d’optimisation donnant parmi un échantillon de solutions, une fonction de bobinage, visant à atténuer ou supprimer une raie potentiellement risquée en termes de nuisances acoustiquesThis thesis deals the quiet design by inverses approaches of synchronous machines with permanent magnets concentrated windings. Our work focuses on the analysis of magnetic noise origin of air gap radial force orders. Firstly a direct electromagnetic model allowed us to determine the spatio-temporal spectrum of air gap radial pressure. The latter offers us the possibility of obtaining step by step and in an analytical way the radial induction in the gap, result of the product of the total magnetomotive force and global air gap permeance. Several machines equipped with a concentrated winding and distributed were evaluated, compared to simulations by finite elements and corroborated by an operational deflection shape on an existing prototype in the laboratory. In the second time two inverse approaches named predictive methodology identified the radial pressure low order origin. Finally, the resolution of the inverse problem is carried out by means of an iterative optimization loop giving among a sample of solutions, a winding function, aimed at attenuating or eliminating a potential risky line in terms of acoustic nuisances
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COSTA, Jackson Jonas Silva. "Soluções radiais e não radiais para a Equação de Hénon na bola unitária." Universidade Federal de Campina Grande, 2010. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/1232.
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Capes
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Chinchapatnam, Phani P. "Radial basis function based meshless methods for fluid flow problems." Thesis, University of Southampton, 2006. https://eprints.soton.ac.uk/72034/.
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This thesis is concerned with the development of meshless methods using radial basis functions for solving fluid flow problems. The advantage of meshless methods over traditional mesh-based methods is that they make use of a scattered set of collocation points in the physical domain and no connec- tivity information is required. An important objective of the present research is to develop novel meshless methods for unsteady flow problems. Symmetric/unsymmetric radial basis function collocation schemes are proposed for solving an unsteady convection-diffusion equation for various Peclet numbers. Both global and compactly supported radial basis functions are used and the convergence behaviours of various radial basis functions are studied. The performance of the presented schemes is shown by using both uniform as well as scattered distribution of points. Numerical results suggest that these schemes are capable of obtaining accurate results for low and medium Peclet numbers. Next, two directions have been explored in this thesis for using radial basis functions to solve large scale problems encountered in fluid flow problems. They are namely, domain decomposition schemes and radial basis functions in finite difference mode. These schemes are shown to be computationally efficient and also aid in circumventing the ill-conditioning problem. The performance of both schemes are evaluated by solving the unsteady convection-diffusion problem. The last part of this thesis is concerned with the solution of the 2D Navier-Stokes equations. Meshless methods based on radial basis collocation and scattered node finite difference schemes are formulated for solving steady and unsteady incompressible Navier-Stokes equations. A novel ghost node strategy is proposed for incor- porating the no-slip boundary conditions. Optimisation strategies based on residual error objective and leave-one-out statistical criterion are proposed to evaluate the optimal shape parameter value in case of the multiquadric RBF for collocation and scattered finite difference approaches respectively. Standard benchmark problems like the driven cavity flows in square and rectangular domains and backward facing step flow problem are solved to study the performance of the developed schemes. Finally, a higher order radial basis function based scattered node finite difference method is proposed for solving the incompressible Navier-Stokes equations.
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Unger, Roman. "Obstacle Description with Radial Basis Functions for Contact Problems in Elasticity." Universitätsbibliothek Chemnitz, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-200900206.
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In this paper the obstacle description with Radial Basis
Functions for contact problems in three dimensional elasticity
will be done. A short Introduction of the idea of Radial Basis
Functions will be followed by the usage of Radial Basis
Functions for approximation of isosurfaces.
Then these isosurfaces are used for the obstacle-description
in three dimensional elasticity contact problems.
In the last part some computational examples will be shown.
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Hunt, David Patrick. "Mesh-free radial basis function methods for advection-dominated diffusion problems." Thesis, University of Leicester, 2005. http://hdl.handle.net/2381/30529.
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This thesis is concerned with the numerical solution of advection-dominated diffusion problems. There are essentially two key aspects to this work: the derivatives of an a priori error estimate for a semi-Lagrangian mesh-free method using radial basis function interpolation to numerically approximate the first-order linear transport problem; and the design and testing of a semi-Lagrangian mesh-less method to numerically solve the full parabolic advection-diffusion problem, using radial basis function Hermite interpolation. We begin by establishing the theory of radical basis function interpolation, including new results for the stability of interpolation via the class of radial basis functions known as polyharmonic splines, as well as error estimates for interpolation by the same class of function. These results provide us with the necessary tools to prove the a priori error estimate for the semi-Lagrangian advection scheme, given certain assumptions on the smoothness of the solution. We then validate both the scheme and the analysis with a series of numerical experiments. By introducing the concept of Hermite interpolation, we develop and implement a new semi-Lagrangian method for the numerical approximation of advection-dominated diffusion problems, which is validated through two numerical experiments.
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Krömer, Stefan. "Nonconvex radially symmetric variational problems." Berlin Logos-Verl, 2005. http://deposit.ddb.de/cgi-bin/dokserv?id=2820900&prov=M&dok_var=1&dok_ext=htm.
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Orsini, Paolo. "A hermite radial basis functions control volume numerical method to simulate transport problems." Thesis, University of Nottingham, 2009. http://eprints.nottingham.ac.uk/28464/.
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This thesis presents a Control Volume (CV) method for transient transport problems where the cell surface fluxes are reconstructed using local interpolation functions that besides interpolating the nodal values of the field variable, also satisfies the governing equation at some auxiliary points in the interpolation stencils. The interpolation function relies on a Hermitian Radial Basis Function (HRBF) mesh less collocation approach to find the solution of auxiliary local boundary/initial value problems, which are solved using the same time integration scheme adopted to update the global control volume solution. By the use of interpolation functions that approximate the governing equation, a form of analytical upwinding scheme is achieved without the need of using predefined interpolation stencils according to the magnitude and direction of the local advective velocity. In this way, the interpolation formula retains the desired information about the advective velocity field, allowing the use of centrally defined stencils even in the case of advective dominant problems. This new CV approach, which is referred to as the CV-HRBF method, is applied to a series of transport problems characterised by high Peclet number. This method is also more flexible than the classical CV formulations because the boundary conditions are explicitly imposed in the interpolation formula, without the need for artificial schemes (e.g. utilising dummy cells). The flexibility of the local meshless character of the CVHRBF is shown in the modelling of the saturated zone of the unconfined aquifer where a mesh adapting algorithm is needed to track the phreatic surface (moving boundary). Due to the use of a local RBF interpolation, the dynamic boundary condition can be applied in an arbitrary number of points on the phreatic surface, independently from the mesh element. The robustness of the Hermite interpolation is exploited to formulate a non-overlapping non-iterative multi-domain scheme where physical matching conditions are satisfied locally, i.e. imposing the continuity of the function and flux at the sub-domain interface.
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Oliveira, Luciano Cordeiro de. "Problemas elípticos semilineares com potenciais ilimitados e/ou com decaimento radial." Universidade Federal de Viçosa, 2010. http://locus.ufv.br/handle/123456789/4907.
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Previous issue date: 2010-02-26In this work we study two class of elliptic problems modeled on unbounded domains. The study of these class of problems is relevant not only in applied mathematics, but also in nonlinear analysis. In the these problems, since the domain is unbounded, there is a lack of compactness of the Sobolev embedding, bringing some difficults to show the convergence of the Palais-Smale sequence. To solve this difficulty we work in a subspace of the usual Sobolev space where we can recover some compactness result. The solutions are obtained by Lagrange multiplier. We give another proof of results in [6] due to Wei-Yue Ding and Wei-Ming Ni, who used to solve The Mountain Pass Theorem and a priori estimates. The results of our study are due to Habao Su, Zhi-Qiang Wang and Michel Willem.
Neste trabalho, estudamos duas classes de problemas elípticos modeladas em domínios ilimitados. O estudo dessas classes de problemas e relevante não só no campo da matemática aplicada, mas também na área de análise não linear. Nesses problemas, como o domínio é ilimitado, há a perda de compacidade da “imersão" de Sobolev, dificultando a convergência da sequência de “soluções" (sequência de Palais Smale). Essa dificuldade é contornada trabalhando num subespaço do espaço de Sobolev usual onde se recupera a compacidade utilizando resultados de imersão. As soluções são obtidas via multiplicadores de Lagrange. Apresentamos uma outra maneira de resolver um problema em [6], devido a Wei-Yue Ding e Wei-Ming Ni, que utilizaram na solução o Teorema do Passo da Montanha e estimativas a priori. Os resultados de nosso estudo são devidos a Habao Su, Zhi-Qiang Wang e Michel Willem.
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Leal, Beatriz Malheiros. "The use of radial basis functions in the numerical solution of option pricing problems." Master's thesis, Instituto Superior de Economia e Gestão, 2018. http://hdl.handle.net/10400.5/16010.
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Mestrado em Mathematical FinanceEsta dissertação tem como objetivo a implementação de uma abordagem numérica moderna à solução da equação diferencial parcial de Black-Scholes, usada para calcular o preço de opções financeiras usando um método sem grelha baseado em funções de base radial. Estas equações são normalmente resolvidas através de métodos numéricos tradicionais tal como o método das diferenças finitas, elementos finitos ou volumes finitos. Mais ainda, o cálculo do preço de opções pode ser feito através de modelos binomiais e/ou simulação de Monte Carlo. A interpolação de pontos utilizando funções de base radial (RBPI) é muito útil quando o número de derivados financeiros é elevado, por exemplo no caso das "basket options" cujo lucro depende do valor de um conjunto de derivados (portefólio). Este método permite concentrar os graus de liberdade do problema nas regiões do domínio mais relevantes, distribuindo os esforços computacionais. Esta dissertação apresenta a implementação do RBPI em vários problemas teste e uma análise de convergência dos problemas relativamente à sua solução exata bem como os respetivos tempos computacionais. Foi possível concluir que o método é válido e que os resultados obtidos são consistentes. No futuro, consideraremos problemas de maior dimensão bem como outras implementações deste método.
This dissertation aims at implementing a modern numerical approach to the solution of the Black-Scholes partial differential equation, used for pricing financial options, by using a meshfree method based on radial basis functions. These equations are normally solved by standard numerical methods like finite differences, finite elements or finite volumes. Additionally, option pricing can also be performed using binomial models and/or Monte Carlo Simulation. Radial Basis Point Interpolation (RBPI) is very useful when the number of derivatives is high, for example in basket options where the pay-off depends on the value of a portfolio (or basket) of derivatives. This method allows to concentrate the degrees of freedom on the most relevant regions in the domain, distributing the computational efforts. This dissertation presents the implementation of the radial basis point interpolation in several test problems and an analysis of the convergence of the discrete problems to the exact solutions, including computational times. We conclude that the method is valid and the obtained results are consistent. In the future, we will consider problems in higher dimensions as well as parallel implementations of this method.
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Zhao, Yangzhang. "Multilevel sparse grid kernels collocation with radial basis functions for elliptic and parabolic problems." Thesis, University of Leicester, 2017. http://hdl.handle.net/2381/39148.
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Radial basis functions (RBFs) are well-known for the ease implementation as they are the mesh-free method [31, 37, 71, 72]. In this thesis, we modify the multilevel sparse grid kernel interpolation (MuSIK) algorithm proposed in [48] for use in Kansa’s collocation method (referred to as MuSIK-C) to solve elliptic and parabolic problems. The curse of dimensionality is a significant challenge in high dimension approximation. A full grid collocation method requires O(Nd) nodal points to construct an approximation; here N is the number of nodes in one direction and d means the dimension. However, the sparse grid collocation method in this thesis only demand O(N logd-1(N)) nodes. We save much more memory cost using sparse grids and obtain a good performance as using full grids. Moreover, the combination technique [20, 54] allows the sparse grid collocation method to be parallelised. When solving parabolic problems, we follow Myers et al.’s suggestion in [90] to use the space-time method, considering time as one spatial dimension. If we apply sparse grids in the spatial dimensions and use time-stepping, we still need O(N2 logd-1(N)) nodes. However, if we use the space-time method, the total number of nodes is O(N logd(N)). In this thesis, we always compare the performance of multiquadric (MQ) basis function and the Gaussian basis function. In all experiments, we observe that the collocation method using the Gaussian with scaling shape parameters does not converge. Meanwhile, in Chapter 3, there is an experiment to show that the space-time method with MQ has a similar convergence rate as a time-stepping method using MQ in option pricing. From the numerical experiments in Chapter 4, MuSIK-C using MQ and the Gaussian always give more rapid convergence and high accuracy especially in four dimensions (T R3) for PDEs with smooth conditions. Compared to some recently proposed mesh-based methods, MuSIK-C shows similar performance in low dimension situation and better approximation in high dimension. In Chapter 5, we combine the Method of Lines (MOL) and our MuSIK-C to obtain good convergence in pricing one asset European option and the Margrabe option, that have non-smooth initial conditions.
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Rahim, Medhat H., Radcliffe Siddo, and Moushira Issa. "Tangram-base Problem Solving in Radical Constructivist Paradigm: High School Student-Teachers Conjectures." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-83015.
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Souza, Simone Silva Frutuoso de [UNESP]. "Algoritmo GRASP especializado aplicado ao problema de reconfiguração de alimentadores em sistemas de distribuição radial." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/87160.
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souza_ssf_me_ilha.pdf: 808468 bytes, checksum: b5fdf2d46cfc01fa8badedc74f75df55 (MD5)Neste trabalho apresenta-se uma metodologia para resolver o problema de reconfiguração de sistemas de distribuição de energia elétrica, que é modelado como um problema de Programação Não Linear Inteiro Misto (PNLIM). Para resolver este problema utilizou-se a metaheurística GRASP especializada. O objetivo do problema de reconfiguração de sistemas de distribuição de energia elétrica é encontrar a melhor topologia radial para um sistema de distribuição de energia elétrica de forma que as perdas ativas do sistema sejam as menores possíveis. Na metodologia proposta, todas as chaves de interconexão do sistema de distribuição estão abertas no inicio do processo e a cada passo um circuito é conectado no sistema e uma solução factível é construída. O algoritmo GRASP foi escrito na linguagem de modelagem matemática AMPL onde a cada iteração é resolvido um problema de programação não linear utilizando o solver comercial KNITRO. Para evidenciar a eficácia da metodologia proposta foram realizados testes com sistemas de 14, 33, 70, 84, 119, 136 e 417 barras, estes resultados são comparados com os resultados encontrados na literatura especializada
This work presents a methodology to solve the electric power distribution systems reconfiguration problem, which is modeled as a Mixed Integer Nonlinear Programming problem (MINLP). Specialized metaheuristic GRASP was used to solve the problem. The aim of the reconfiguration problem is to find the best topology for a radial electric power distribution system so that the active power losses are as small as possible. In the proposed methodology, at the beginning of the solution process all switches that interconnect the distribution system are open and in each next step a circuit is connected to the distribution system and therefore a feasible solution is constructed. The GRASP algorithm was written in AMPL mathematical modeling language where in each iteration was solved a nonlinear programming problem using the commercial solver KNITRO. To demonstrate the effectiveness of the proposed methodology, tests were performed with distribution systems of 14, 33, 70, 84, 119, 136, and 417 buses, these results are compared with results found in literature
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Finan, Marcel Basil. "Existence of Many Sign Changing Non Radial Solutions for Semilinear Elliptic Problems on Annular Domains." Thesis, University of North Texas, 1998. https://digital.library.unt.edu/ark:/67531/metadc278251/.
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Forbes, Andrew. "Customer-Side Voltage Regulation to Mitigate PV-induced Power Quality Problems in Radial Distribution Networks." Thesis, Forbes, Andrew (2018) Customer-Side Voltage Regulation to Mitigate PV-induced Power Quality Problems in Radial Distribution Networks. Honours thesis, Murdoch University, 2018. https://researchrepository.murdoch.edu.au/id/eprint/41909/.
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The objective of this thesis is to illustrate the effectiveness of customer-side voltage regulation in unbalanced distribution networks, under increasing levels of distributed generation, with the overarching aim of reducing voltage magnitude and voltage imbalance violations. The voltage regulators will be installed between the point of common coupling and the customer point of access. This thesis focusses on a static timeseries load flow study that has been developed using Python 3.6.
Load flow simulations have been carried out at PV penetrations levels from 30 to 100 per cent, utilising three different loads models––constant power, constant impedance and an equal impedance-power ratio. An algorithm has been developed for selecting the location of the voltage regulators, which uses the performance of the network in terms of voltage magnitude and voltage imbalance. The test network is based on a real four-wire multipleearthed neutral distribution network in Perth, Western Australia. Real and reactive power readings from customer meters have been used. The voltage regulator model is constructed around an autotransformer regulator with 32 steps and an effective adjustment range of ±10%.
The proposed voltage regulation methodology in this thesis is effective in addressing the problems of voltage magnitude violations and to a lesser extent, voltage imbalance, in the presence of high PV penetration. However, the benefits this solution offers in terms of voltage violation reduction, loss reduction and autonomous operation, are not enough to overcome the current cost of these devices. The existing on-load tap changer solution modelled in this thesis for comparison, is shown to deliver better technical outcomes in terms of network performance, for less cost.
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Souza, Simone Silva Frutuoso de. "Algoritmo GRASP especializado aplicado ao problema de reconfiguração de alimentadores em sistemas de distribuição radial /." Ilha Solteira, 2013. http://hdl.handle.net/11449/87160.
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Orientador: Rubén Augusto Romero LázaroCoorientador: Marina Lavorato de Oliveira
Banca: José Roberto Sanches Mantovani
Banca: Arturo Suman Bretas
Resumo: Neste trabalho apresenta-se uma metodologia para resolver o problema de reconfiguração de sistemas de distribuição de energia elétrica, que é modelado como um problema de Programação Não Linear Inteiro Misto (PNLIM). Para resolver este problema utilizou-se a metaheurística GRASP especializada. O objetivo do problema de reconfiguração de sistemas de distribuição de energia elétrica é encontrar a melhor topologia radial para um sistema de distribuição de energia elétrica de forma que as perdas ativas do sistema sejam as menores possíveis. Na metodologia proposta, todas as chaves de interconexão do sistema de distribuição estão abertas no inicio do processo e a cada passo um circuito é conectado no sistema e uma solução factível é construída. O algoritmo GRASP foi escrito na linguagem de modelagem matemática AMPL onde a cada iteração é resolvido um problema de programação não linear utilizando o solver comercial KNITRO. Para evidenciar a eficácia da metodologia proposta foram realizados testes com sistemas de 14, 33, 70, 84, 119, 136 e 417 barras, estes resultados são comparados com os resultados encontrados na literatura especializada
Abstract: This work presents a methodology to solve the electric power distribution systems reconfiguration problem, which is modeled as a Mixed Integer Nonlinear Programming problem (MINLP). Specialized metaheuristic GRASP was used to solve the problem. The aim of the reconfiguration problem is to find the best topology for a radial electric power distribution system so that the active power losses are as small as possible. In the proposed methodology, at the beginning of the solution process all switches that interconnect the distribution system are open and in each next step a circuit is connected to the distribution system and therefore a feasible solution is constructed. The GRASP algorithm was written in AMPL mathematical modeling language where in each iteration was solved a nonlinear programming problem using the commercial solver KNITRO. To demonstrate the effectiveness of the proposed methodology, tests were performed with distribution systems of 14, 33, 70, 84, 119, 136, and 417 buses, these results are compared with results found in literature
Mestre
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Cetin, Suat. "Analytical Solution Of A Crack Problem In A Radially Graded Fgm." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/3/12609120/index.pdf.
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The objective of this study is to determine stress intensity factors (SIFs) for a crack in a radially graded FGM layer on a substrate. Functionally graded coating with an edge crack perpendicular to the interface and a homogeneous substrate are bonded together. In order to make the problem analytically tractable, geometry is modeled as an FGM strip attached to a homogeneous layer. Introducing the elastic foundation underneath the homogeneous layer, an FGM coating on a thin walled cylinder can be modeled. At first, governing equations are obtained from stress displacement and equilibrium equations. Then using an assumed form of solution in terms of Fourier Transforms for displacements and applying the boundary conditions, a singular integral equation is obtained for the mode-I problem. Solving this singular integral equation numerically, stress intensity factors are obtained as functions of crack length, strip thicknesses and inhomogeneity parameter.
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Hinds, Chantal Simonette. "ESR studies of radical adsorbed on aluminosilicate catalysis." Thesis, Queen Mary, University of London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243865.
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Kianifar, Mohammed R., and I. Felician Campean. "Performance evaluation of metamodelling methods for engineering problems: towards a practitioner guide." Springer, 2019. http://hdl.handle.net/10454/17192.
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YesMetamodelling or surrogate modelling techniques are frequently used across the engineering disciplines in conjunction with expensive simulation models or physical experiments. With the proliferation of metamodeling techniques developed to provide enhanced performance for specific problems, and the wide availability of a diverse choice of tools in engineering software packages, the engineering task of selecting a robust metamodeling technique for practical problems is still a challenge. This research introduces a framework for describing the typology of engineering problems, in terms of dimensionality and complexity, and the modelling conditions, reflecting the noisiness of the signals and the affordability of sample sizes, and on this basis presents a systematic evaluation of the performance of frequently used metamodeling techniques. A set of metamodeling techniques, selected based on their reported use for engineering problems (i.e. Polynomial, Radial Basis Function, and Kriging), were systematically evaluated in terms of accuracy and robustness against a carefully assembled set of 18 test functions covering different types of problems, sampling conditions and noise conditions. A set of four real-world engineering case studies covering both computer simulation and physical experiments were also analysed as validation tests for the proposed guidelines. The main conclusions drawn from the study are that Kriging model with Matérn 5/2 correlation function performs consistently well across different problem types with smooth (i.e. not noisy) data, while Kriging model with Matérn 3/2 correlation function provides robust performance under noisy conditions, except for the very high noise conditions, where the Kriging model with nugget appears to provide better models. These results provide engineering practitioners with a guide for the choice of a metamodeling technique for problem types and modelling conditions represented in the study, whereas the evaluation framework and benchmarking problems set will be useful for researchers conducting similar studies.
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Balan, Anil. "Theoretical and experimental investigations on radial electromagnetic forces in relation to vibration problems of induction machines." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq24067.pdf.
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Warner, Carol. "Peace education in Hiroshima : problems of a radical movement in post-1945 Japan /." Title page, contents and introduction only, 1989. http://web4.library.adelaide.edu.au/theses/09AR/09arw279.pdf.
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GALIMBERTI, R. "FORMULAÇÃO do Método dos Elementos de Contorno para Resolver Problemas de Helmholtz Usando Funções de Interpolação de Base Radial Sem Regularização." Universidade Federal do Espírito Santo, 2018. http://repositorio.ufes.br/handle/10/9768.
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Previous issue date: 2018-03-01O objetivo deste trabalho é propor uma nova formulação para o Método dos Elementos de Contorno denominada aqui como MECID-2 (Método dos Elementos de Contorno com Integração Direta sem Regularização), que faz uso das funções de base radial para aproximar integrais de domínio, mas que possui uma estratégia de solução diferente do modelo apresentado na formulação já validada com êxito, a MECID Regularizada. Foram propostos cinco problemas governados pela Equação de Helmholtz para a validação desta formulação em que os resultados da MECID-2 foram comparados com a MECID Regularizada, tomando como parâmetro a solução analítica do problema, quando houver, ou a solução aproximada pelo Método dos Elementos Finitos (MEF). Outro parâmetro importante avaliado nos resultados é a importância do refinamento da malha de contorno e da quantidade de pontos internos inseridos no domínio. São geradas curvas de desempenho através do cálculo do erro médio percentual para cada malha, demonstrando a convergência e a precisão de cada método.
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Skrudupis, Patrikas. "Tikrovės problema Jean'o Baudrillard'o filosofijoje." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2005. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2005~D_20050602_221029-28883.
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The study deals with J. Baudrillad’s conception of reality as hyper reality. J. Baudrillad’s conception of hyper reality and the lost of referential reality is presented through the analysis of numerous writings, articles as well as critical texts. First of all, the author’s conception of simulated and non-referential reality is compared with the classical understanding of reality, which contains dualistic tension, whereas the other is nuclear and the distinctions between object/subject, true/false, real/unreal are no longer possible. Then the author of the study also brings the theme of ‘produced reality’ and mass mediated life as it is represented in J. Baudrillad’s philosophical writings. The influence of hyper reality on the practical way of life is also analyzed. Finally, the themes of non-referential language, philosophical dialogue and possibility for classical philosophy are considered.
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Corbetta, Chiara <1988>. "La movimentazione delle opere d'arte: radici di un problema attuale." Master's Degree Thesis, Università Ca' Foscari Venezia, 2014. http://hdl.handle.net/10579/4535.
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La tesi approfondisce le tematiche legate allo sviluppo dei prestiti dal 1600 ad oggi.
Il progetto comporta una ricerca storica dall'origine dei prestiti d'arte fino alle polemiche contemporanee con un'appendice sui problemi legati alle opere d'arte contemporanea durante le movimentazioni.
Per completezza si è analizzato l'iter amministrativo per l'esportazioni di opere con l'analisi di un caso di gestione dei prestiti per una mostra d'arte.
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Gerace, Salvadore. "A Meshless Method Approach for Solving Coupled Thermoelasticity Problems." Honors in the Major Thesis, University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/1223.
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This item is only available in print in the UCF Libraries. If this is your Honors Thesis, you can help us make it available online for use by researchers around the world by following the instructions on the distribution consent form at http://library.ucf.edu/Systems/DigitalInitiatives/DigitalCollections/InternetDistributionConsentAgreementForm.pdf You may also contact the project coordinator, Kerri Bottorff, at kerri.bottorff@ucf.edu for more information.Bachelors
Engineering and Computer Science
Mechanical Engineering
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Al-Jawary, Majeed Ahmed Weli. "The radial integration boundary integral and integro-differential equation methods for numerical solution of problems with variable coefficients." Thesis, Brunel University, 2012. http://bura.brunel.ac.uk/handle/2438/6449.
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The boundary element method (BEM) has become a powerful method for the numerical solution of boundary-value problems (BVPs), due to its ability (at least for problems with constant coefficients) of reducing a BVP for a linear partial differential equation (PDE) defined in a domain to an integral equation defined on the boundary, leading to a simplified discretisation process with boundary elements only. On the other hand, the coefficients in the mathematical model of a physical problem typically correspond to the material parameters of the problem. In many physical problems, the governing equation is likely to involve variable coefficients. The application of the BEM to these equations is hampered by the difficulty of finding a fundamental solution. The first part of this thesis will focus on the derivation of the boundary integral equation (BIE) for the Laplace equation, and numerical results are presented for some examples using constant elements. Then, the formulations of the boundary-domain integral or integro-differential equation (BDIE or BDIDE) for heat conduction problems with variable coefficients are presented using a parametrix (Levi function), which is usually available. The second part of this thesis deals with the extension of the BDIE and BDIDE formulations to the treatment of the two-dimensional Helmholtz equation with variable coefficients. Four possible cases are investigated, first of all when both material parameters and wave number are constant, in which case the zero-order Bessel function of the second kind is used as fundamental solution. Moreover, when the material parameters are variable (with constant or variable wave number), a parametrix is adopted to reduce the Helmholtz equation to a BDIE or a BDIDE. Finally, when material parameters are constant (with variable wave number), the standard fundamental solution for the Laplace equation is used in the formulation. In the third part, the radial integration method (RIM) is introduced and discussed in detail. Modifications are introduced to the RIM, particularly the fact that the radial integral is calculated by using a pure boundary-only integral which relaxes the “star-shaped” requirement of the RIM. Then, the RIM is used to convert the domain integrals appearing in both BDIE and BDIDE for heat conduction and Helmholtz equations to equivalent boundary integrals. For domain integrals consisting of known functions the transformation is straightforward, while for domain integrals that include unknown variables the transformation is accomplished with the use of augmented radial basis functions (RBFs). The most attractive feature of the method is that the transformations are very simple and have similar forms for both 2D and 3D problems. Finally, the application of the RIM is discussed for the diffusion equation, in which the parabolic PDE is initially reformulated as a BDIE or a BDIDE and the RIM is used to convert the resulting domain integrals to equivalent boundary integrals. Three cases have been investigated, for homogenous, non-homogeneous and variable coefficient diffusion problems.
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Carvalho, Marcus Rodrigo. "Estudo de técnicas eficientes para a resolução do problema de fluxo de potência para sistemas de distribuição radial." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/18/18133/tde-27072006-164213/.
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Este trabalho descreve uma abordagem do método primal-dual barreira logarítmica (MPDBL) associado ao método de Newton modificado para a resolução do problema de fluxo de potência para sistemas de distribuição radial. Também foi realizado um estudo comparativo com duas técnicas clássicas de solução do problema de fluxo potência para redes de distribuição radial. São os métodos: Backward/Forward Sweep e o método proposto por M. Baran e F. Wu, que é baseado na técnica de Newton-Raphson. Este método utiliza uma matriz Jacobiana modificada que atende a característica radial dos sistemas de distribuição. Nos testes comparativos serão considerados todos os parâmetros do sistema. Os algoritmos de solução serão analisados em suas propriedades de convergência e será realizado um teste de robustez. Os resultados dos testes realizados em 4 sistemas (4, 10, 34 e 70 barras) e o teste comparativo entre os métodos evidenciam a melhor metodologia na solução do problema de fluxo de potência para sistemas radiaisThis work describes an approach on primal-dual logarithmic barrier method (PDLBM) associate to the method of Newton modified for the resolution of the problem of power flow for radial distribution systems. Also a comparative study with two classic techniques of solution of the flow problem was carried through power for nets of radial distribution. They are the methods: Backward/Forward Sweep and the method considered for M. Baran and F. Wu, that is based on the technique of Newton-Raphson. This method uses modified Jacobiana matrix that takes care of the radial characteristic of the distribution systems. In the comparative tests all will be considered the parameters of the system. The solution algorithms will be analyzed in its properties of convergence and will be carried through a robustness test. The results of the tests carried through in 4 systems (4, 10, 34 and 70 bus) and the comparative test between the methods evidence the best methodology in the solution of the problem of power flow for radial systems
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Alves, Diego Zilio. "A natureza comportamental da mente : behaviorismo radical e filosofia da mente /." Marília : [s.n.], 2009. http://hdl.handle.net/11449/91763.
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Resumo: O presente trabalho pretende delinear uma possível interpretação do behaviorismo radical como teoria da mente, o que significa, em outros termos, contextualizá-lo no âmbito da filosofia da mente. Para tanto, primeiramente apresentaremos as principais teorias que figuram na filosofia da mente contemporânea, incluindo suas teses centrais e seus respectivos problemas. Em seguida, trataremos dos fundamentos do behaviorismo radical enquanto filosofia da ciência e enquanto teoria do comportamento. Esses dois passos servirão ao propósito de estabelecer os parâmetros da discussão subseqüente entre behaviorismo radical e filosofia da mente. Nesse sentido, o primeiro problema que pretendemos responder é: o que é a mente? Trata-se de um problema conceitual que envolve o mapeamento dos fenômenos normalmente caracterizados como mentais. Veremos que, para o behaviorismo radical, a mente é comportamento. Já o segundo problema que pretendemos responder é: qual a natureza da mente? - problema que, no contexto do behaviorismo radical, deve ser substituído pelo seguinte: qual a natureza do comportamento? Discorrer sobre a natureza de um fenômeno implica investigar quais são as características essenciais à sua existência. Trata-se, portanto, de um problema ontológico. Sugeriremos que as características essenciais para a existência do comportamento podem ser contempladas pelo posicionamento metafísico denominado relacionismo substancial. Em tempo, além dessas duas questões principais, discorreremos ao longo do trabalho sobre diversos problemas levantados pelas teorias da mente contemporâneas, tais como o problema da subjetividade, o problema do fisicalismo, o problema dos limites da ciência, o problema mente-corpo, o problema da causalidade mental, o problema do significado, o problema do reducionismo, o problema das qualidades das experiências, o problema do conhecimento ... (Resumo completo, clicar acesso eletrônico abaixo)Abstract: The aim of this work is to delineate a possible interpretation of radical behaviorism as a theory of mind. That means putting radical behaviorism in the context of philosophy of mind. To do so, firstly we will present the main theories of contemporary philosophy of mind, including its central thesis and its respective problems. Next, we will present the principles of radical behaviorism as a philosophy of science and as a theory of behavior. Those steps will serve to establish the parameters for subsequent discussion between radical behaviorism and the problems of philosophy of mind. The first problem with which we pretend to deal is the conceptual problem of mind: what is mind? As we will see, for radical behaviorism the mind is behavior. The second problem with which we pretend to deal is the ontological problem of mind: what is the nature of mind? In the radical behaviorist context, the question must be substituted by this: what is the nature of behavior? Discussions about the nature of things demands investigating what characteristics are essential to its existence. We will suggest that the essential characteristics of the existence of behavior can be contemplated by the metaphysical view denominated substantial relationism. Moreover, in addition to our two principal problems, we will discuss through this work several problems of philosophy of mind, such as the problem of subjectivity, the problem of physicalism, the problem of science limits, the mind-body problem, the problem of mental causation, the problem of meaning, the problem of reductionism, the problem of qualitative character of experiences, the problem of privileged knowledge, the problem of qualia, and others. In the end, we hope that this work may represent a step toward the construction of a radical behaviorist theory of mind
Orientador: Jonas Gonçalves Coelho
Coorientador: Kester Carrara
Banca: Tereza Maria de Azevedo Pires Serio
Banca: João de Fernandes Teixeira
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Oliveira, José Francisco Alves de. "Soluções Radiais Positivas para Problemas Elípticos Envolvendo Crescimento Crítico." Universidade Federal da Paraíba, 2009. http://tede.biblioteca.ufpb.br:8080/handle/tede/7461.
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Previous issue date: 2009-04-22Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
In this work we present results of existence, non-existence and uniqueness of radial positive solutions for elliptic semilinear equations in subdomains of euclidean plane. We consider nonlinearities involving critical growth the type Trudinger- Moser. The technique used is shooting method introduced in 1905 by Severini [21]. This is a iterative method which permits determine the solution of a contour problem by analysis of approximated solutions of a family of initial value problems generated by himself. For its iteractive caracter, the shooting method it has been used effectively in applied mathematics, for exemple in the computational mathematical, where specific algorithms are used to perform such interactions. Here in an abstract approach through analytic techniques of continuity we examined whether an iteration converges to a solution of the contour problem under study.
Neste trabalho apresentamos resultados de existência, não existência e unicidade de soluções radiais positivas para equações elípticas semilineares em subdomínios do plano euclidiano. As não linearidades que consideramos envolvem crescimento crítico do tipo Trudinger-Moser. Utilizamos uma técnica conhecida como shooting method introduzida em 1905 por Severini [21]. Um método iterativo que permite determinar a solução de um problema de contorno por meio da análise de soluções aproximadas de uma família de problemas de valor inicial geradas por este. Por seu caráter iterativo, o shooting method tem sido utilizado com eficiência em matemática aplicada, como por exemplo, matemática computacional, onde formula-se algorítmos específicos para executar tais iterações. Aqui, dentro de um enfoque abstrato, utilizaremos técnicas analíticas de continuidade para analisar se determinada iteração converge para uma solução do problema de contorno em estudo.
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Valdez, Oyague Martín. "El mal radical del corazón humano: problemas fundamentales de la ética de Kant." Master's thesis, Pontificia Universidad Católica del Perú, 2013. http://tesis.pucp.edu.pe/repositorio/handle/123456789/4911.
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Este trabajo constituye una investigación sobre el mal radical tal como aparece en la
primera parte de La religión dentro de los límites de la mera razón (en adelante, Religión).
De lo que se trata es de presentar de forma crítica la tesis de Immanuel Kant que afirma una
maldad innata en la naturaleza humana (R 6:32-39). Y si bien la tesis aparece de forma
explícita y sistemática únicamente en dicha obra, nos preocuparemos en mostrar que,
mutatis mutandis, atraviesa toda la filosofía moral kantiana, dado que articula una visión
del ser humano que se hace presente en todas sus obras de moral, así como en sus escritos
de antropología y de historia.Tesis
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MONÇÃO, Thyago de Lellys Faria. "Análise Numérica de Problemas envolvendo Equações Diferenciais Parciais e Equações Integrais através de Funções de Base Radial." reponame:Repositório Institucional da UNIFEI, 2012. http://repositorio.unifei.edu.br/xmlui/handle/123456789/1044.
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Funções de base radial são aquelas que apresentam simetria radial, ou seja, dependem apenas (exceto por alguns parâmetros conhecidos) da distância entre o centro da função e um ponto genérico. Com uma definição tão geral, existe uma infinidade de funções deste tipo. Neste trabalho, técnicas utilizadas para a interpolação de dados dispersos são aplicadas na resolução de equações diferenciais parciais e equações integrais. Desta forma, será empregado um método numérico sem malha, baseado nas funções de base radial. Dois métodos de colocação, assimétrico e simétrico, são apresentados de forma breve e sucinta e então aplicados a diversos problemas de interesse. Em aplicações deste tipo, as duas mais importantes questões envolvidas, na aplicação do método são: (i) que tipo de função de base utilizar e (ii) qual o valor de seu parâmetro de forma. Assim, um conjunto de funções comumente utilizadas na literatura é escolhido e seus resultados apresentados. Para escolha do parâmetro de forma, diferentes estratégias podem ser utilizadas para que se faça a decisão do melhor valor. Foram utilizadas duas técnicas para a escolha de um “bom” valor para o parâmetro de forma. A mais simples por tentativa e erro e outra por validação cruzada. Para uma discussão mais clara, as técnicas propostas foram aplicadas em equações que possuem solução analítica disponível, permitindo uma fácil verificação dos resultados obtidos. Em alguns casos, os resultados obtidos com o presente método e confrontado com outros obtidos por método numéricos clássicos.
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Alves, Bruna Pardim. "Busca tabu reformulada aplicada ao problema de operação de sistemas de distribuição de energia elétrica radiais /." Ilha Solteira, 2019. http://hdl.handle.net/11449/182469.
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Orientador: Ruben Augusto Romero LazaroResumo: Este trabalho apresenta uma proposta baseada na meta-heurística Busca Tabu, chamada de Busca Tabu Reformulada para resolver o problema de operação ótima dos sistemas de distribuição, utilizando uma estratégia integrada de reconfiguração e alocação de bancos de capacitores fixos e chaveados para obter a topologia radial que apresente o menor custo de operação. Para encontrar a topologia radial inicial foi aplicado o algoritmo de Prim, em que foi obtida uma solução reconfigurada, e essa solução encontrada foi submetida à uma heurística para alocação de capacitores fixos e chaveados. A proposta de solução inicial é submetida ao algoritmo de Busca Tabu Reformulada que utiliza uma vizinhança que considera como solução vizinha uma topologia vizinha da topologia radial corrente e com a proposta de alocação de bancos de capacitores modificada. Como proposta da metodologia Busca Tabu Reformulada o procedimento é repetido até um critério de parada definido. Todos os programas foram escritos em linguagem FORTRAN 77. Os algoritmos propostos foram testados com os sistemas de 33, 70, 84 e 136 barras.
Abstract: This paper presents a proposal based on the Tabu Search metaheuristic called Tabu Search Reformulated to solve the problem of optimal operation of the distribution systems, using an integrated strategy of reconfiguration and allocation of fixed and switched capacitor banks to obtain the radial topology which presents the lowest operating cost. To find the initial radial topology the Prim algorithm was applied, in which a reconfigured solution was obtained, and this solution was submitted to a heuristic for the allocation of fixed and switched capacitors. The initial solution proposal is submitted to the Reformulated Tabu Search algorithm that uses a neighborhood that considers as neighbor solution a neighboring topology of the current radial topology and with the proposed allocation of modified capacitor banks. As a proposal of the Tabu Search Reformulated methodology, the procedure is repeated up to a defined stop criterion. All the programs were written in FORTRAN 77 language. The proposed algorithms were tested with the 33, 70, 84 and 136-node systems.
Mestre
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Gilligan, Philip A. "Well-motivated reformists or nascent radicals: How do applicants to the degree in social work see social problems, their origins and solutions?" Oxford University Press, 2007. http://hdl.handle.net/10454/2721.
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NoThis article reports ways in which applicants to the Degree in Social Work see `social problems¿, their origins and possible solutions to them. What is demonstrated is that whilst applicants are concerned about a range of problems, those which could be broadly classified as `anti-social behaviours by individuals or groups¿ predominate, in contrast to those which could be defined as `aspects of the social structure which have an adverse impact on individuals or groups¿. Applicants are much more likely to suggest `individual¿ rather than `social¿ causes and are most likely to suggest `liberal/reformist¿ solutions. It is argued, in the context of frame analysis, that pre-existing views will usually impact strongly on how students respond to the knowledge and challenges offered during training. The article aims to place discussion within consideration of wider issues, particularly whether social work in Britain can maintain its historic commitment to social justice and prevent itself becoming an increasingly uncritical tool of the UK government¿s social authoritarianism. Finally, it seeks to raise questions about whether social work education can assist qualifying workers to develop and maintain resiliently radical approaches to practice, which are also effective in bringing positive change to vulnerable and disadvantaged people.
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Pereira, Gisliane Alves. "Multiplicidade de soluções radiais do problema de Dirichlet para o p-Laplaciano." reponame:Repositório Institucional da UnB, 2007. http://repositorio.unb.br/handle/10482/5495.
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Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Exatas, Departamento de Matemática, 2007.Submitted by Érika Rayanne Carvalho (carvalho.erika@ymail.com) on 2010-09-09T17:34:55Z No. of bitstreams: 1 2007_GislianeAlvesPereira.pdf: 646708 bytes, checksum: 5e3545c5a38f7d3ebf81fdab5d01ff95 (MD5)
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Neste trabalho examinamos a existência e a multiplicidade de soluções radiais do problema de Dirichlet. Usando o método de "Shooting" mostramos que esse problema tem infinitas soluções, cada uma com um número específico de zeros interiores em [0, 1]. _____________________________________________________________________________ ABSTRACT
In this work we examine the existence and the multiplicity of radial solutions of the Dirichlet problem. Using the Shooting method we show that this problem has an infinite number of radial solutions, each one with a specific number of interior zeros in [0, 1].
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Alves, Diego Zilio [UNESP]. "A natureza comportamental da mente: behaviorismo radical e filosofia da mente." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/91763.
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alves_dz_me_mar.pdf: 953969 bytes, checksum: 976e357b345098e9424e02053aa842d0 (MD5)O presente trabalho pretende delinear uma possível interpretação do behaviorismo radical como teoria da mente, o que significa, em outros termos, contextualizá-lo no âmbito da filosofia da mente. Para tanto, primeiramente apresentaremos as principais teorias que figuram na filosofia da mente contemporânea, incluindo suas teses centrais e seus respectivos problemas. Em seguida, trataremos dos fundamentos do behaviorismo radical enquanto filosofia da ciência e enquanto teoria do comportamento. Esses dois passos servirão ao propósito de estabelecer os parâmetros da discussão subseqüente entre behaviorismo radical e filosofia da mente. Nesse sentido, o primeiro problema que pretendemos responder é: o que é a mente? Trata-se de um problema conceitual que envolve o mapeamento dos fenômenos normalmente caracterizados como mentais. Veremos que, para o behaviorismo radical, a mente é comportamento. Já o segundo problema que pretendemos responder é: qual a natureza da mente? – problema que, no contexto do behaviorismo radical, deve ser substituído pelo seguinte: qual a natureza do comportamento? Discorrer sobre a natureza de um fenômeno implica investigar quais são as características essenciais à sua existência. Trata-se, portanto, de um problema ontológico. Sugeriremos que as características essenciais para a existência do comportamento podem ser contempladas pelo posicionamento metafísico denominado relacionismo substancial. Em tempo, além dessas duas questões principais, discorreremos ao longo do trabalho sobre diversos problemas levantados pelas teorias da mente contemporâneas, tais como o problema da subjetividade, o problema do fisicalismo, o problema dos limites da ciência, o problema mente-corpo, o problema da causalidade mental, o problema do significado, o problema do reducionismo, o problema das qualidades das experiências, o problema do conhecimento...
The aim of this work is to delineate a possible interpretation of radical behaviorism as a theory of mind. That means putting radical behaviorism in the context of philosophy of mind. To do so, firstly we will present the main theories of contemporary philosophy of mind, including its central thesis and its respective problems. Next, we will present the principles of radical behaviorism as a philosophy of science and as a theory of behavior. Those steps will serve to establish the parameters for subsequent discussion between radical behaviorism and the problems of philosophy of mind. The first problem with which we pretend to deal is the conceptual problem of mind: what is mind? As we will see, for radical behaviorism the mind is behavior. The second problem with which we pretend to deal is the ontological problem of mind: what is the nature of mind? In the radical behaviorist context, the question must be substituted by this: what is the nature of behavior? Discussions about the nature of things demands investigating what characteristics are essential to its existence. We will suggest that the essential characteristics of the existence of behavior can be contemplated by the metaphysical view denominated substantial relationism. Moreover, in addition to our two principal problems, we will discuss through this work several problems of philosophy of mind, such as the problem of subjectivity, the problem of physicalism, the problem of science limits, the mind-body problem, the problem of mental causation, the problem of meaning, the problem of reductionism, the problem of qualitative character of experiences, the problem of privileged knowledge, the problem of qualia, and others. In the end, we hope that this work may represent a step toward the construction of a radical behaviorist theory of mind
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Wittman, Amanda Barrett. "What happens to the radical potential of gender mainstreaming? : problems of implementation and institutionalisation in gendered organisations." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/5506.
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Rapidly spreading in popularity over the past fifteen years, gender mainstreaming has been adopted worldwide by state, supra state and international organizations as the "most modern‟ policy for ensuring gender equality. Yet, there is general agreement that it has not succeeded in achieving its radical potential. In this thesis, I bring together policy literature on bureaucracies, the civil service, and gender mainstreaming with work done on gender, work and organizations as a way to better understand the partial success and uneven implementation and institutionalization of what is supposedly a transformational agenda. To date, gender scholars have underplayed the "stickiness‟ of gender and its effects upon actors and everyday practices in political and state organizations. I argue that the "stickiness‟ of gender in organisations presents a formidable obstacle to the implementation and institutionalization of gender mainstreaming. I also argue that insufficient attention has been paid to the "embodied costs‟ of actors who act as internal gender mainstreaming advocates both in terms of the costs to the individuals and the impact of these costs on the prospects for the successful implementation and institutionalisation of a radical change agenda. Through an ethnographic examination of the Scottish Executive from 2006-2007, I probe the analytic question framing this thesis: what happens to the radical potential of gender mainstreaming during its implementation and institutionalisation in governmental bureaucracies? Using the sociological method of institutional ethnography, I provide evidence of ways that continued reliance on highly committed individuals and everyday bureaucratic practices continue to limit the radical success of gender mainstreaming at the Scottish Executive. I contend that the radical promise of gender mainstreaming is hindered because it is a strategy which must work within the confines of fossilised norms manifested in masculinist bureaucracies and because it is paradoxically predicated on changing bureaucratic norms through the use of the same bureaucratic practices it attempts to transform. By examining the everyday experience of "doing‟ gender mainstreaming in the case of a sub-state government in the UK, the Scottish Executive, I trace the ways that the radical promises of the gender mainstreaming agenda become diluted. The thesis examines challenges to the gender mainstreaming agenda and adds to wider discussions about the plausibility of gender mainstreaming‟s radical potential. In addition, my thesis moves forward methodological discussions in feminist politics by demonstrating the possibility of using institutional ethnography in political science as an effective way to operationalise, analyze and link multiple levels of politics from a gendered perspective. My analysis of local experiences of gender mainstreaming provides insight into the international trend of gender mainstreaming because it takes seriously the experiences of individuals who work within organizations, the role of organizations in limiting change agendas, and the international context within which the mainstreaming strategy unfolds.
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Garofoli, Duilio [Verfasser], and Katerina [Akademischer Betreuer] Harvati. "Neanderthal cognitive equivalence : Epistemological problems and a critical analysis from radical embodiment / Duilio Garofoli ; Betreuer: Katerina Harvati." Tübingen : Universitätsbibliothek Tübingen, 2015. http://d-nb.info/1168232430/34.
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Alahari, Karteek. "Efficient inference and learning for computer vision labelling problems." Thesis, Oxford Brookes University, 2010. https://radar.brookes.ac.uk/radar/items/d1a8c73a-2f62-4ea3-a8b3-f5aee513c22e/1.
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Discrete energy minimization has recently emerged as an indispensable tool for computer vision problems. It enables inference of the maximum a posteriori solutions of Markov and conditional random fields which can be used to model labelling problems in vision. When formulating such problems in an energy minimization framework there are three main issues that need to be addressed: (i) How to perform efficient inference to compute the optimal solution: (ii) How to incorporate prior knowledge into the model: and (iii) How to learn the parameter values. This thesis focuses on these aspects and presents novel solutions to address them. As computer vision moves towards the era of large videos and gigapixel images, computational efficiency is becoming increasingly important. We present two novel methods to improve the efficiency of energy minimization algorithms. The first method works by "recycling" results from previous problem instances. The second simplifies the energy minimization problem by "reducing" the number of variables in the energy function. We demonstrate a substantial improvement in the running time of various labelling problems such as interactive image and video segmentation, object recognition, stereo matching. In the second part of the thesis we expIore the use of natural image statistics for the single view reconstruction problem, where the task is to recover a theatre-stage representation (containing planar surfaces and their geometrical relationships to each other) from a single 2D image, To this end. we introduce a class of multi-label higher order functions to model these statistics based on the distribution of geometrical features of planar surfaces. We also show that this new class of functions can be solved exactly with efficient graph cut methods. The third part of the thesis addresses the problem of learning the parameters of the energy function. Although several methods have been proposed to learn the model parameters from training data, they suffer from various drawbacks, such as limited applicability or noisy estimates due to poor approximations. We present an accurate and efficient learning method, and demonstrate that it is widely applicable.
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SANTOS, Luís Guilherme Cunha. "Método da Quadratura Diferencial com Funções de Base Radial em Problemas de Dinâmica dos Fluidos e Transferência de Calor." reponame:Repositório Institucional da UNIFEI, 2012. http://repositorio.unifei.edu.br/xmlui/handle/123456789/1232.
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O uso de Funções de Base Radial (FBR) para a interpolação de dados dispersos e para solução de equações diferenciais tem emergido como uma ferramenta importante nos últimos anos. A principal razão é sua capacidade de lidar com qualquer tipo de malha ou mesmo discretizações sem malha (meshfree). Abordagens globais têm sido aplicadas com sucesso, mas elas estão limitadas a um número relativamente baixo de nós (algumas centenas), devido à baixa esparcidade e o extremo mal condicionamento dos sistemas algébricos. Versões locais têm sido desenvolvidas para superar estes inconvenientes. Entre elas, o Método de Quadratura Diferencial Local usando FBR (MQDL-FBR) tem sido proposto há alguns anos e parece ser muito promissor para o tratamento de problemas com discretizações complexas (milhares ou milhões de nós). Para o cálculo dos coeficientes de ponderação obtidos através do MDQLFBR, condições de determinação acerca da FBR foram desenvolvidas neste trabalho. A FBR Multiquádrica (Mq) foi escolhida devido à sua representação muito precisa em comparação com outros tipos de FBR, e por satisfazer as condições de determinação. Neste trabalho discute-se, através de experimentos numéricos, os erros numéricos e a convergência do MQDL-FBR na solução de equações diferenciais parciais (EDP). Esses experimentos foram feitos para a equação de Poisson em um domínio quadrado unitário usando-se malhas estruturadas, vários stencils diferentes e algumas soluções analíticas. A influência no erro numérico adicionando um termo não-linear de primeiras derivadas na Equação de Poisson também foi analisada. Verifica-se a independência do parâmetro de forma com o refinamento de malha h, conforme demonstrado em pesquisas recentes. Outros resultados são discutidos. Duas aplicações utilizando o MQDL-FBR foram feitas. Primeiro em um problema de convecção forçada em uma cavidade quadrada, também chamado na literatura como problema da caixa de sapato. Em seguida, um problema de convecção natural em uma cavidade quadrada. Em ambos, pontos fora do domínio foram utilizados para o cálculo e reposição de alguns valores junto à fronteira pelo MQDL-FBR. Resultados são comparados com os da literatura e discutidos.
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Soltau, Carl Peter. "Nitroxide trapping of radical species formed from the reaction of sulfoxides with reactive oxygen species." Thesis, Queensland University of Technology, 2021. https://eprints.qut.edu.au/210339/1/Carl_Soltau_Thesis.pdf.
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This project focussed on an in-depth evaluation of an established methodology that uses dimethyl sulfoxide (DMSO) as a reactive solvent with a profluorescent nitroxide (PFN) to detect and quantify particulate matter-derived ROS (Reactive Oxygen Species). Additionally, a novel approach which utilized cyclic sulfoxide tetrahydrothiophene-1-oxide (THTO) as the reactive solvent was investigated. The reactions of these sulfoxides with ROS generated from multiple sources in the presence of nitroxide radical scavengers were investigated. The results of these experiments show that nitroxides can display much broader reactivity than the simple radical scavenging processes that have previously been accepted.