GMPLS is a still developing protocol family which is indented to assume the role of a control plane in transport networks. GMPLS is designed to provide traffic engineering in transport networks composed of different network technologies such as wavelength switched optical networks, Ethernet networks, point-to-point microwave links, etc. Integrating the different network technologies while using label switched paths to provide traffic engineering poses a challenge. The purpose of integrating multiple technologies under a single GMPLS control plane is to enable rapid service provisioning and efficient traffic engineering. Traffic engineering in networks provides two primary advantages, network resource utilization optimization and the ability to provide Quality of Service. Utilizing network resources more efficiently translates to lower expenditures for the network provider. Quality of Service can be used to provide the customer with for example guaranteed minimum bandwidth packet services. Specifically this thesis focused on the problems of signaling and establishing Forward Adjacency Label Switched Paths (FA-LSPs), and on a experimental method of connecting different network technologies. A testbed integrating an Ethernet network and a wave length division multiplexing network was used to show that the proposed solutions can work in practice. / GMPLS består av en samling protokoll under utveckling, de är tänkta att anta rollen som kontrollplan i transportnätverk. GMPLS är designat för att tillhandahålla trafikplanering i transportnätverk bestående av flera olika nätverksteknologier såsom Ethernet, våglängds switchande nätverk m.fl. Integration av dessa olika nätverksteknologier under ett gemensamt kontrollplan och uppsättning av ”label switched paths” i dataplanet är en utmaning. Syftet med att integrera multipla teknologier under ett ensamt GMPLS kontroll plan är att snabbt kunna tillhandahålla tjänster över nätverket samt möjliggöra advancerad trafikplanering. Trafikplanering i nätverk ger två stora fördelar, optimering av utnyttjandet av nätverksresurser samt ökade möjligheter att erbjuda ”Quality of Service” till kunder. Bättre utnyttjande av nätverksresurser innebär lägre kostnader för nätverksleverantören medans ”Quality of Service” kan ge kunden t.ex. en garanterad bandbredd. Specifikt fokuserar denna avhandling på problemen med att signalera och etablera ”Forwarding Adjaceny Label Switched Paths” samt en experimentell metod som båda sammankopplar olika typer av nätverk. En testbed bestående av ett Ethernet nätverk samt ett optiskt våglängdsswitchande nätverk användes för att visa att lösningarna kan fungera i praktiken.

A análise isogeométrica (AIG) de estruturas consiste em construir a geometria exata ou aproximada de um modelo computacional a partir de funções criadas por meio de tecnologias de Computer Aided Design (CAD), tais como B-Splines, NURBS (Non-Uniform Rational BSplines) e T-splines, e aplicar o conceito de análise isoparamétrica, ou seja, representar o espaço de solução para as variáveis independentes em termos das mesmas funções que representam a geometria. O presente trabalho visa o estudo da análise isogeométrica aplicada a vigas planas, com a utilização de B-Splines e NURBS para aproximação de deslocamentos. São desenvolvidos modelos isogeométricos de vigas planas baseados nas hipóteses de Bernoulli- Euler e Timoshenko, e alguns exemplos de aplicação são realizados a fim de comparar os resultados numéricos com soluções analíticas, mostrando boa concordância. Uma questão pertinente à AIG corresponde à imposição de vínculos em pontos do domínio em que as funções básicas não sejam interpolatórias ou os vínculos desejados não forem diretamente relacionados aos graus de liberdade do elemento, que é o caso do elemento de viga de Bernoulli-Euler, já que as rotações geralmente não são tidas como graus de liberdade mas há a necessidade de se prescrever condições de contorno/conexão nas mesmas para descrever problemas físicos. Essa questão é tratada no presente trabalho através dos Métodos de Lagrange e de penalidade. São realizados exemplos de aplicação construídos com elementos de viga de Bernoulli-Euler utilizando os métodos de Lagrange e de penalidade na imposição de vínculos e na conexão entre pontos de regiões de domínio. / Isogeometric analysis (IGA) consists on building the geometry of the computational model with functions created by Computer Aided Design (CAD) technologies, such as B-Splines, NURBS (Non-Uniform Rational B-Splines) and T-Splines. Then, isoparametric concept is employed, that is, the solution space is represented by means of the same functions used to describe the geometry. The aim of the present contribution is the study of isogeometric analysis applied to 2D beams with interpolation via B-splines and NURBS. Two-dimensional isogeometric beam formulations based on Bernoulli-Euler and Timoshenko assumptions are presented. Some examples of application are given and results are compared to analytical solutions, showing good agreement. An important issue about IGA corresponds to the imposition of constraints at points of domain in which the shape functions are not interpolatory, or the desired constraints are not directly related to the degrees of freedoms. This may occur for Bernoulli-Euler beams since rotations are not usually defined as degrees of freedom, but they need to be assessed for prescription of some boundary/connection conditions. This is done in present contribution by employing both Lagrange and penalty methods. Some examples of structures composed by 2D isogeometric Bernoulli-Euler beam elements are solved by using Lagrange and Penalty methods to impose constraints and to make the connection between domain regions.

abstract: Thousands of high-resolution images are generated each day. Segmenting, classifying, and analyzing the contents of these images are the key steps in image understanding. This thesis focuses on image segmentation and classification and its applications in synthetic, texture, natural, biomedical, and industrial images. A robust level-set-based multi-region and texture image segmentation approach is proposed in this thesis to tackle most of the challenges in the existing multi-region segmentation methods, including computational complexity and sensitivity to initialization. Medical image analysis helps in understanding biological processes and disease pathologies. In this thesis, two cell evolution analysis schemes are proposed for cell cluster extraction in order to analyze cell migration, cell proliferation, and cell dispersion in different cancer cell images. The proposed schemes accurately segment both the cell cluster area and the individual cells inside and outside the cell cluster area. The method is currently used by different cell biology labs to study the behavior of cancer cells, which helps in drug discovery. Defects can cause failure to motherboards, processors, and semiconductor units. An automatic defect detection and classification methodology is very desirable in many industrial applications. This helps in producing consistent results, facilitating the processing, speeding up the processing time, and reducing the cost. In this thesis, three defect detection and classification schemes are proposed to automatically detect and classify different defects related to semiconductor unit images. The first proposed defect detection scheme is used to detect and classify the solder balls in the processor sockets as either defective (Non-Wet) or non-defective. The method produces a 96% classification rate and saves 89% of the time used by the operator. The second proposed defect detection scheme is used for detecting and measuring voids inside solder balls of different boards and products. The third proposed defect detection scheme is used to detect different defects in the die area of semiconductor unit images such as cracks, scratches, foreign materials, fingerprints, and stains. The three proposed defect detection schemes give high accuracy and are inexpensive to implement compared to the existing high cost state-of-the-art machines. / Dissertation/Thesis / Ph.D. Electrical Engineering 2010

No description available.

Meshless methods provide a highly continuous approximation field, convenient for thin structures like shells. Nevertheless, the lack of Kronecker Delta property makes the formulation of essential boundary conditions not straightforward, as the trial and test fields cannot be tailored to boundary values. Similar problem arise when different approximation regions must be joined, in a multi-region problem, such as kinks, folds or joints. This work presents three approaches to impose both kinematic conditions: the well known Lagrange Multiplier method, used since the beginning of the Element Free Galerkin method; a pure penalty approach; and the recently rediscovered alternative of Nitsche\'s Method. We use the EFG discretization technique for thick Reissner-Mindlin shells and adapt the weak form as to separate displacement and rotational degrees of freedom and obtain suitable and separate stabilization parameters. This approach enables the modeling of discontinuous shells and local refinement on multi-region problems. / Métodos sem malha geram campos de aproximação com alta continuidade, convenientes para estruturas finas como cascas. No entanto, a ausência da propriedade de Delta de Kronecker dificulta a formulação de condições essenciais de contorno, já que os campos de aproximação e teste não podem ser moldados aos valores de contorno. Um problema similar aparece quando diferentes regiões de aproximação precisam ser juntadas em um problema multi-regiões como dobras, vincos ou junções. Este trabalho apresenta três métodos de imposição ambas condições cinemáticas: o já conhecido método dos multiplicadores de Lagrange, usado desde o começo do método de Galekin sem elementos (EFG); uma abordagem de penalidade pura; e o recentemente redescoberto método de Nitsche. Nós usamos a técnica de discretização com EFG para cascas espessas de Reissner-Mindlin e adaptamos a forma fraca de forma a separar graus de liberdade de deslocamento e rotação e obter coeficientes de estabilização diferentes e apropriados. Essa abordagem permite a modelagem de cascas discontínuas e o refinamento local em problemas multi-regiões.

[pt] Este trabalho apresenta um ambiente computacional para modelagem geométrica aplicada à análise por elementos finitos usando multi-regiões e superfícies paramétricas representadas por NURBS. O principal objetivo é gerar modelos 3D para serem usados em simulações numéricas baseadas no Método de Elementos Finitos (MEF). Nessa proposta, a metodologia adotada consiste na combinação de alguns aspectos da modelagem geométrica tais como a detecção automática de regiões e a interseção de superfícies com geração de malhas de elementos finitos. No contexto da programação orientada a objetos, uma nova organização de classes para o modelador geométrico usado neste trabalho, denominado MG, é apresentada. Essa organização de classes permite a implementação do ambiente proposto, mantendo a interface com o usuário tão simples e eficiente quanto à versão original. A organização de classes também provê suporte para a geração de modelos usados em análise por elementos finitos. Enquanto as malhas de elementos finitos requeridas para simulações numéricas são geradas por algoritmos específicos implementados no modelador MG, os atributos são gerenciados por um sistema, denominado ESAM (Extensible System Attributes Management), que também é incorporado ao MG. Esse sistema permite que os atributos do modelador MG sejam configurados para o uso em diversos tipos de problemas de engenharia. A estrutura de dados usada neste ambiente é representada por um enfoque híbrido baseado na combinação de uma representação CGC (Complete Geometric Complex) do modelo e na estrutura de dados estendida do modelador MG. Além disso, a determinação da interseção de superfícies é realizada usando um algoritmo implementado no MG, enquanto que a representação CGC é responsável pelo reconhecimento de multi-regiões. O algoritmo de interseção de superfícies é modificado para tratar casos especiais não considerados na sua versão original. / [en] This work presents a computational environment for geometric modeling applied to finite-element analysis using multi-regions and parametric surfaces represented as NURBS. The main goal is to generate 3D models to be used in numerical simulations based on the Finite-Element Method (FEM). For this purpose, the adopted methodology consists of combining some aspects of geometric modeling, such as automatic region detection and surface intersection, with finite-element mesh generation. In the context of Object-Oriented Programming, a new class organization for the geometric modeler used in this work, called MG (Mesh Generation), is presented. This class organization allows the implementation of the proposed environment, keeping the user interface as simple and efficient as in the original version of the MG modeler. The proposed class organization also provides support for the generation of models used in finite-element analysis. While the finite-element meshes required for the numerical simulations are generated by specific algorithms implemented in MG, the attributes are managed by a system called ESAM (Extensible System Attributes Management), which also is incorporated into MG. This system allows the customization of simulation attributes in the MG modeler for use in different types of Engineering problems. The data structure used in this environment is represented by a hybrid approach based on the combination of a CGC (Complete Geometric Complex) representation and the MG`s data structure, which has been extended for this purpose. Moreover, the computation of surface intersections is accomplished by using an algorithm implemented in the MG, while the CGC representation is responsible for multi-region recognition. The surface-intersection algorithm has been modified in order to handle special cases that have not been treated in the original version.

Meshless methods provide a highly continuous approximation field, convenient for thin structures like shells. Nevertheless, the lack of Kronecker Delta property makes the formulation of essential boundary conditions not straightforward, as the trial and test fields cannot be tailored to boundary values. Similar problem arise when different approximation regions must be joined, in a multi-region problem, such as kinks, folds or joints. This work presents three approaches to impose both kinematic conditions: the well known Lagrange Multiplier method, used since the beginning of the Element Free Galerkin method; a pure penalty approach; and the recently rediscovered alternative of Nitsche\'s Method. We use the EFG discretization technique for thick Reissner-Mindlin shells and adapt the weak form as to separate displacement and rotational degrees of freedom and obtain suitable and separate stabilization parameters. This approach enables the modeling of discontinuous shells and local refinement on multi-region problems. / Métodos sem malha geram campos de aproximação com alta continuidade, convenientes para estruturas finas como cascas. No entanto, a ausência da propriedade de Delta de Kronecker dificulta a formulação de condições essenciais de contorno, já que os campos de aproximação e teste não podem ser moldados aos valores de contorno. Um problema similar aparece quando diferentes regiões de aproximação precisam ser juntadas em um problema multi-regiões como dobras, vincos ou junções. Este trabalho apresenta três métodos de imposição ambas condições cinemáticas: o já conhecido método dos multiplicadores de Lagrange, usado desde o começo do método de Galekin sem elementos (EFG); uma abordagem de penalidade pura; e o recentemente redescoberto método de Nitsche. Nós usamos a técnica de discretização com EFG para cascas espessas de Reissner-Mindlin e adaptamos a forma fraca de forma a separar graus de liberdade de deslocamento e rotação e obter coeficientes de estabilização diferentes e apropriados. Essa abordagem permite a modelagem de cascas discontínuas e o refinamento local em problemas multi-regiões.

La segmentation d'image constitue une étape importante dans le traitement d'image et de nombreuses questions restent ouvertes. Il a été montré récemment, dans le cas d'une segmentation à deux régions homogènes, que l'utilisation de contours actifs polygonaux fondés sur la minimisation d'un critère issu de la théorie de l'information permet d'aboutir à un algorithme ultra-rapide qui ne nécessite ni paramètre à régler dans le critère d'optimisation, ni connaissance a priori sur les fluctuations des niveaux de gris. Cette technique de segmentation rapide et non supervisée devient alors un outil élémentaire de traitement.L'objectif de cette thèse est de montrer les apports de cette brique élémentaire pour la conception de nouvelles techniques de segmentation plus complexes, permettant de dépasser un certain nombre de limites et en particulier :- d'être robuste à la présence dans les images de fortes inhomogénéités ;- de segmenter des objets non connexes par contour actif polygonal sans complexifier les stratégies d'optimisation ;- de segmenter des images multi-régions tout en estimant de façon non supervisée le nombre de régions homogènes présentes dans l'image.Nous avons pu aboutir à des techniques de segmentation non supervisées fondées sur l'optimisation de critères sans paramètre à régler et ne nécessitant aucune information sur le type de bruit présent dans l'image. De plus, nous avons montré qu'il était possible de concevoir des algorithmes basés sur l'utilisation de cette brique élémentaire, permettant d'aboutir à des techniques de segmentation rapides et dont la complexité de réalisation est faible dès lors que l'on possède une telle brique élémentaire. / Image segmentation is an important step in many image processing systems and many problems remain unsolved. It has recently been shown that when the image is composed of two homogeneous regions, polygonal active contour techniques based on the minimization of a criterion derived from information theory allow achieving an ultra-fast algorithm which requires neither parameter to tune in the optimized criterion, nor a priori knowledge on the gray level fluctuations. This algorithm can then be used as a fast and unsupervised processing module. The objective of this thesis is therefore to show how this ultra-fast and unsupervised algorithm can be used as a module in the conception of more complex segmentation techniques, allowing to overcome several limits and particularly:- to be robust to the presence of strong inhomogeneity in the image which is often inherent in the acquisition process, such as non-uniform illumination, attenuation, etc.;- to be able to segment disconnected objects by polygonal active contour without complicating the optimization strategy;- to segment multi-region images while estimating in an unsupervised way the number of homogeneous regions in the image.For each of these three problems, unsupervised segmentation techniques based on the optimization of Minimum Description Length criteria have been obtained, which do not require the tuning of parameter by user or a priori information on the kind of noise in the image. Moreover, it has been shown that fast segmentation techniques can be achieved using this segmentation module, while keeping reduced implementation complexity.

The effect of electromagnetically induced transparency is observed, using nanocelland microcell. The EIT-resonance with good parameters (high contrast and small FWHM) is obtained in thick cells. The EIT-resonance splitting in magnetic field is observed for the cases of D1-line of 85Rb and 85Rb. The theoretical model, explaining the EIT-resonance components frequency shift dependence on magnetic field strength is presented. The theoretical and experimental results are compared and good agreement is shown. Also the EIT-resonance behavior in hyperfine Paschen-Back regime is presented and explained. For the first time the N-type resonance in microcell is observed. Good parameters of theN-type resonance in microcell are obtained. It allows us to observe the N-type resonance behavior in magnetic field. The N-resonance splitting in magnetic field is observed for the cases of 85Rb and 85Rb. The theoretical calculations of the N-resonance components frequency shift dependence on magnetic field is presented. The theoretical and experimental results are compared and good agreement is shown. Also the N-resonance behavior in hyperfine Paschen-Back regime is presented and explained. Simultaneous observation of N- and EIT-resonance is shown. Comparison of EIT- and N-resonance is made

O presente trabalho trata do desenvolvimento de formulações numéricas para avaliar o comportamento mecânico de estruturas compostas planas, no contexto de elasticidade linear e mecânica da fratura não linear. As formulações propostas são baseadas no Método dos Elementos de Contorno (MEC), por meio das representações integrais singular e hiper singular dos problemas elastostáticos. A técnica de multi-regiões é considerada para acoplar a interface de sólidos multifásicos. O MEC é uma técnica numérica robusta e precisa para analisar o fenômeno da fratura em sólidos. Esse método numérico apresenta uma natural redução na dimensionalidade do problema, tornando mais simples a modelagem das superfícies de fratura. Além disso, essa redução de dimensionalidade faz também com que o tratamento de interfaces materiais em estruturas compostas seja uma tarefa menos árdua. Com o uso da solução fundamental de Kelvin nas representações integrais, materiais isotrópicos podem ser considerados para constituir as estruturas compostas. Por outro lado, utilizando a solução fundamental de Cruse & Swedlow, também é possível lidar, de maneira geral, com materiais anisotrópicos em estruturas compostas. Nessas estruturas, as fraturas são assumidas como ocorrendo ao longo das interfaces e o comportamento não linear é introduzido pelo modelo coesivo de fratura, o qual é aplicável a materiais quase frágeis. Nessas análises, o sistema não linear de equações pode ser solucionado utilizando dois distintos algoritmos de resolução iterativa. O primeiro sempre leva em consideração a rigidez elástica da estrutura e é, portanto denominado Operador Constante (OC). Já o segundo é denominado Operador Tangente (OT), pois considera uma rigidez tangente à resposta estrutural não linear, o que resulta em melhores taxas de convergência em comparação ao OC. Como aplicações das formulações, estruturas compostas teóricas foram analisadas em regime elástico. Além disso, testes experimentais de fratura em espécimes de concreto e madeira também foram simulados. A comparação dos resultados com as referências demonstrou que, as formulações foram efetivas e precisas para avaliar respostas mecânicas de estruturas, seja em regime elástico linear ou nos testes de fratura quase frágil. / The present work deals the development of numerical formulations to evaluate the mechanical behaviour of plane composed structures, in the context of linear elasticity and nonlinear fracture mechanics. The proposed formulations are based on the Boundary Element Method (BEM), through its classical singular and hyper singular integral equations. The multi-region technique is adopted to couple the interfaces of non-homogeneous multiphase bodies. The BEM is a robust and accurate numerical technique to analyse fracture phenomena in solids. This numerical method presents a mesh dimensionality reduction, which makes easier the modelling of cracks surfaces. Besides, this dimensionality reduction also makes the treatment of interfaces in composed structures a less complex task. Considering the use of Kelvin fundamental solutions at the integrals equations, isotropic materials can be represent as parts of the composed structures. On the other hand, using Cruse & Swedlow fundamental solution it is also possible to deal with general anisotropic materials. At the composed structures, cracks can propagate along the materials interfaces and the cohesive crack model is responsible for the nonlinear structural behaviour of the quasi-brittle failures. The nonlinear system of equations at the fracture analyses is solved using two different algorithms for iterative resolution. The first always takes into account the structure elastic strength and, hence it is called Constant Operator (CO). On the other hand, the second is denominated Tangent Operator (TO) due to the fact that it considers strengths at the tangent directions of the nonlinear structural response. Therefore, convergence rates are faster when compared with the CO. As applications, composed structures were analysed with the developed formulations in linear elastic range. In addition, experimental fracture testes performed in concrete and wood specimens were also analysed. The confront of obtained results with the reference ones show that, the formulation was effective and accurate to evaluate the mechanical responses of composed structures in linear elastic range, and also to perform nonlinear quasi-brittle fracture tests.