Orientador: Gustavo Michel Mendoza La Torre / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Física, 2012

This thesis investigates the high frequency discharging characteristics of the lithium iron phosphate battery. The investigation focuses on effects of the high-frequency current on the dischargeable capacity of the battery. Included are the current profiles of triangle, saw-tooth, and trapezoidal waves, which are produced from commonly used DC-DC converters. Experimental results show that the current with the higher frequency has less dischargeable capacity. On the other hand, the converter current resonating into and out from the battery results the additional losses. The possible reasons that affect the discharged capacities are explained by the equivalent circuit of the battery.

A study of the hydraulic jump on a trapezoidal prismatic channel and roughened beds is presented. Extensive measurements have been made regarding the characteristics of hydraulic jumps as sequent depths, wing fluctuations, energy dissipation and jump length on artificially roughened beds for Froude numbers between 4.16 and 14.58. Three different types of prismatic roughness elements and nine different roughness patterns were installed separately on channel bottom and side walls throughout the experiments to obtain rough surfaces. Strip roughness elements were built from fiberglass sheets and implemented perpendicular to the flow direction. To avoid cavitation, roughness elements were designed in that way that the crests of the elements are not protruding into the flow. The founded properties were compared with the available data in literature and with the properties of hydraulic jump occurred on smooth bed.

This study investigated the delivery of electron arc treatment with a trapezoidal aperture. The aim of the investigation is to reduce the nonuniformity of the dose distribution, which is caused by the variation of the patient contour from superior to inferior. The characteristics of static electron beam were first investigated. Then a measurement-based algorithm was developed and implemented as a computer program called EarcMU to calculate the monitor units required for delivering the prescribed dose with a trapezoidal aperture. The central axis percentage depth dose was found to be independent of source-to-surface distance (SSD) and the width of the aperture. The inplane profiles of a trapezoidal aperture show that the dose decreases longitudinally from the wide to the narrow end of the trapezoidal aperture. The EarcMU program was verified using two cylindrical water phantoms. The measured dose and the dose calculated by the program agreed within 2.1% in the typical clinical conditions. A simple method was also proposed for determining the trapezoidal aperture for an individual patient. Under the same conditions, the trapezoidal apertures calculated by this method along with the open aperture were used to deliver treatments to several conical phantoms. Significant improvement in the uniformity of dose distribution was observed. On average, the flatness index of the longitudinal dose distribution from superior to inferior decreases dramatically from 8% for open aperture down to 0.58% for trapezoidal aperture. The results are clinically significant, indicating that delivering the electron arc treatment using a trapezoidal aperture can bring more uniform dose to the patient regardless of the change of patient contour from superior to inferior.

A metodologia de projeto semi-customizado usando associações trapezoidais de transistores (TATs) é especialmente viável para o projeto de circuitos integrados mistos analógico- digitais. Vários trabalhos foram desenvolvidos demonstrando exemplos de aplicações que geraram bons resultados utilizando esta metodologia. Entretanto, ficou evidente a falta de ferramentas de CAD apropriadas para automatizar o processo de síntese dos circuitos. Para preencher esta lacuna, foi desenvolvido o LIT, uma ferramenta de CAD especializada na geração do layout de células analógicas utilizando associações de transistores. O principal desafio da técnica de associações trapezoidais é a escolha adequada da associação equivalente ao transistor simples, de modo que os efeitos negativos da substituição deste transistor no desempenho do circuito sejam os menores possíveis. Podem existir diversas opções de associações equivalentes, e a escolha da mais adequada nem sempre é uma tarefa direta e intuitiva.O objetivo deste trabalho é a criação de ferramentas de auxílio ao projeto de circuitos analógicos utilizando a técnica de associação série-paralela de transistores MOS (Metal- Oxide-Semiconductor), desde o dimensionamento do circuito até a descrição do layout em formato de troca. Pretende-se fazer com que o tempo total de projeto seja reduzido e seus custos diminuídos. Além disso, o projeto visando a manufaturabilidade, de fundamental importância em tecnologias sub-micrométricas, também é abordado na ferramenta através da busca pela regularidade do layout. Um novo conceito de associação de transistores é introduzido: a associação do tipo T (TST - T-Shaped Transistor). Esta associação caracteriza-se por seu formato trapezoidal, porém sem limite quanto ao tamanho dos transistores unitários, os quais são considerados, em trabalhos anteriores sobre TATs (associações trapezoidais de transistores), como sendo todos iguais. Assim, uma ou duas variáveis livres a mais ficam disponíveis ao projetista, dando a liberdade da escolha de até quatro dimensões para os TSTs, o que faz com que o projeto se torne mais flexível. A modelagem deste tipo de associação é desenvolvida neste trabalho de modo que os efeitos de segunda ordem sejam previstos no desempenho geral do circuito e a verificação experimental comparada com simulações. / The semi-custom design methodology using trapezoidal associations of transistors (TATs) is specially viable for the design of mixed-signal integrated circuits. Several works have been developed demonstrating examples of applications that generated good results using this methodology. However, there is a lack of specific CAD tools able to automate the synthesis procedure. In order to fill this need, the LIT tool was developed. LIT is a CAD tool specialized in layout generation of analog cells using associations of transistors. The main challenge is the choice of the correct equivalent association for a given single transistor, in such a way that negative effects related to this substitution are minimized. The most adequate choice is not a direct and intuitive task, because many options of associations exist. The goal of this work is to develop a tool for the aid of analog circuits design using series-parallel associations of MOS transistors, from circuit sizing phase to layout description. Total time and costs can be reduced with this tool. Moreover, design for manufacturability is also improved through layout regularity. A new concept of associations of transistors is introduced: the T-Shaped Transistor (TST). The main characteristic of this association is its trapezoidal format, but with no limit on the sizes of unit transistors, which were fixed in previous works about TATs (Trapezoidal Associations of Transistors). Then, one or two more free variables are available to the designer, giving him the possibility to work with up to four dimensions for the TSTs. A model of this kind of association is developed in this work, since it is needed to prevent or minimize second order effects that degrade circuit performance. Experimental comparison with simulations are also presented.

A metodologia de projeto semi-customizado usando associações trapezoidais de transistores (TATs) é especialmente viável para o projeto de circuitos integrados mistos analógico- digitais. Vários trabalhos foram desenvolvidos demonstrando exemplos de aplicações que geraram bons resultados utilizando esta metodologia. Entretanto, ficou evidente a falta de ferramentas de CAD apropriadas para automatizar o processo de síntese dos circuitos. Para preencher esta lacuna, foi desenvolvido o LIT, uma ferramenta de CAD especializada na geração do layout de células analógicas utilizando associações de transistores. O principal desafio da técnica de associações trapezoidais é a escolha adequada da associação equivalente ao transistor simples, de modo que os efeitos negativos da substituição deste transistor no desempenho do circuito sejam os menores possíveis. Podem existir diversas opções de associações equivalentes, e a escolha da mais adequada nem sempre é uma tarefa direta e intuitiva.O objetivo deste trabalho é a criação de ferramentas de auxílio ao projeto de circuitos analógicos utilizando a técnica de associação série-paralela de transistores MOS (Metal- Oxide-Semiconductor), desde o dimensionamento do circuito até a descrição do layout em formato de troca. Pretende-se fazer com que o tempo total de projeto seja reduzido e seus custos diminuídos. Além disso, o projeto visando a manufaturabilidade, de fundamental importância em tecnologias sub-micrométricas, também é abordado na ferramenta através da busca pela regularidade do layout. Um novo conceito de associação de transistores é introduzido: a associação do tipo T (TST - T-Shaped Transistor). Esta associação caracteriza-se por seu formato trapezoidal, porém sem limite quanto ao tamanho dos transistores unitários, os quais são considerados, em trabalhos anteriores sobre TATs (associações trapezoidais de transistores), como sendo todos iguais. Assim, uma ou duas variáveis livres a mais ficam disponíveis ao projetista, dando a liberdade da escolha de até quatro dimensões para os TSTs, o que faz com que o projeto se torne mais flexível. A modelagem deste tipo de associação é desenvolvida neste trabalho de modo que os efeitos de segunda ordem sejam previstos no desempenho geral do circuito e a verificação experimental comparada com simulações. / The semi-custom design methodology using trapezoidal associations of transistors (TATs) is specially viable for the design of mixed-signal integrated circuits. Several works have been developed demonstrating examples of applications that generated good results using this methodology. However, there is a lack of specific CAD tools able to automate the synthesis procedure. In order to fill this need, the LIT tool was developed. LIT is a CAD tool specialized in layout generation of analog cells using associations of transistors. The main challenge is the choice of the correct equivalent association for a given single transistor, in such a way that negative effects related to this substitution are minimized. The most adequate choice is not a direct and intuitive task, because many options of associations exist. The goal of this work is to develop a tool for the aid of analog circuits design using series-parallel associations of MOS transistors, from circuit sizing phase to layout description. Total time and costs can be reduced with this tool. Moreover, design for manufacturability is also improved through layout regularity. A new concept of associations of transistors is introduced: the T-Shaped Transistor (TST). The main characteristic of this association is its trapezoidal format, but with no limit on the sizes of unit transistors, which were fixed in previous works about TATs (Trapezoidal Associations of Transistors). Then, one or two more free variables are available to the designer, giving him the possibility to work with up to four dimensions for the TSTs. A model of this kind of association is developed in this work, since it is needed to prevent or minimize second order effects that degrade circuit performance. Experimental comparison with simulations are also presented.

A metodologia de projeto semi-customizado usando associações trapezoidais de transistores (TATs) é especialmente viável para o projeto de circuitos integrados mistos analógico- digitais. Vários trabalhos foram desenvolvidos demonstrando exemplos de aplicações que geraram bons resultados utilizando esta metodologia. Entretanto, ficou evidente a falta de ferramentas de CAD apropriadas para automatizar o processo de síntese dos circuitos. Para preencher esta lacuna, foi desenvolvido o LIT, uma ferramenta de CAD especializada na geração do layout de células analógicas utilizando associações de transistores. O principal desafio da técnica de associações trapezoidais é a escolha adequada da associação equivalente ao transistor simples, de modo que os efeitos negativos da substituição deste transistor no desempenho do circuito sejam os menores possíveis. Podem existir diversas opções de associações equivalentes, e a escolha da mais adequada nem sempre é uma tarefa direta e intuitiva.O objetivo deste trabalho é a criação de ferramentas de auxílio ao projeto de circuitos analógicos utilizando a técnica de associação série-paralela de transistores MOS (Metal- Oxide-Semiconductor), desde o dimensionamento do circuito até a descrição do layout em formato de troca. Pretende-se fazer com que o tempo total de projeto seja reduzido e seus custos diminuídos. Além disso, o projeto visando a manufaturabilidade, de fundamental importância em tecnologias sub-micrométricas, também é abordado na ferramenta através da busca pela regularidade do layout. Um novo conceito de associação de transistores é introduzido: a associação do tipo T (TST - T-Shaped Transistor). Esta associação caracteriza-se por seu formato trapezoidal, porém sem limite quanto ao tamanho dos transistores unitários, os quais são considerados, em trabalhos anteriores sobre TATs (associações trapezoidais de transistores), como sendo todos iguais. Assim, uma ou duas variáveis livres a mais ficam disponíveis ao projetista, dando a liberdade da escolha de até quatro dimensões para os TSTs, o que faz com que o projeto se torne mais flexível. A modelagem deste tipo de associação é desenvolvida neste trabalho de modo que os efeitos de segunda ordem sejam previstos no desempenho geral do circuito e a verificação experimental comparada com simulações. / The semi-custom design methodology using trapezoidal associations of transistors (TATs) is specially viable for the design of mixed-signal integrated circuits. Several works have been developed demonstrating examples of applications that generated good results using this methodology. However, there is a lack of specific CAD tools able to automate the synthesis procedure. In order to fill this need, the LIT tool was developed. LIT is a CAD tool specialized in layout generation of analog cells using associations of transistors. The main challenge is the choice of the correct equivalent association for a given single transistor, in such a way that negative effects related to this substitution are minimized. The most adequate choice is not a direct and intuitive task, because many options of associations exist. The goal of this work is to develop a tool for the aid of analog circuits design using series-parallel associations of MOS transistors, from circuit sizing phase to layout description. Total time and costs can be reduced with this tool. Moreover, design for manufacturability is also improved through layout regularity. A new concept of associations of transistors is introduced: the T-Shaped Transistor (TST). The main characteristic of this association is its trapezoidal format, but with no limit on the sizes of unit transistors, which were fixed in previous works about TATs (Trapezoidal Associations of Transistors). Then, one or two more free variables are available to the designer, giving him the possibility to work with up to four dimensions for the TSTs. A model of this kind of association is developed in this work, since it is needed to prevent or minimize second order effects that degrade circuit performance. Experimental comparison with simulations are also presented.

This dissertation is a study of the dynamics of one-dimensional unimodal maps and is mainly concerned with those maps which are trapezoidal. The trapezoidal function, f_e, is defined for eΣ(0,1/2) by f_e(x)=x/e for xΣ[0,e], f_e(x)=1 for xΣ(e,1-e), and f_e(x)=(1-x)/e for xΣ[1-e,1]. We study the symbolic dynamics of the kneading sequences and relate them to the analytic dynamics of these maps. Chapter one is an overview of the present theory of Metropolis, Stein, and Stein (MSS). In Chapter two a formula is given that counts the number of MSS sequences of length n. Next, the number of distinct primitive colorings of n beads with two colors, as counted by Gilbert and Riordan, is shown to equal the number of MSS sequences of length n. An algorithm is given that produces a bisection between these two quantities for each n. Lastly, the number of negative orbits of size n for the function f(z)=z^2-2, as counted by P.J. Myrberg, is shown to equal the number of MSS sequences of length n. For an MSS sequence P, let H_ϖ(P) be the unique common extension of the harmonics of P. In Chapter three it is proved that there is exactly one J(P)Σ[0,1] such that the itinerary of λ(P) under the map is λ(P)f_e is H_ϖ(P). In Chapter four it is shown that only period doubling or period halving bifurcations can occur for the family λf_e, λΣ[0,1]. Results concerning how the size of a stable orbit changes as bifurcations of the family λf_e occur are given. Let λΣ[0,1] be such that 1/2 is a periodic point of λf_e. In this case 1/2 is superstable. Chapter five investigates the boundary of the basin of attraction of this stable orbit. An algorithm is given that yields a graph directed construction such that the object constructed is the basin boundary. From this we analyze the Hausdorff dimension and measure in that dimension of the boundary. The dimension is related to the simple β-numbers, as defined by Parry.

The main idea behind stabilisation by diaphragm action is to create a deep beam thatcan resist horizontal loads acting on a structure. It is achieved by connecting the sheetingto the primary structure of the roof so that the edge beams resist the bending momentthrough normal stresses and the sheeting resists the shear force through shear stresses.An essential assumption of a functional diaphragm system is a sufficient connectionbetween the sheeting and the primary structure.In this thesis, the global behaviour of a diaphragm, as well as possible failure modesof sheeting of different thicknesses, are investigated.A laboratory experiment is conducted in the first part of the thesis. In the experiment,two types of self-drilling screws in combination with three different plate thicknesses aretested in shear. Slip flexibility of the screws is evaluated based on the experiment andcompared to flexibilities according to European Recommendations for the Application ofMetal Sheeting Acting as a Diaphragm.In the second part of the thesis, a finite element simulation is performed on two structuresto investigate the global behaviour of the diaphragm. The experimental results are,additionally, implemented into the finite element model.In the last part, hand calculations are performed based on analytical formulas given inEuropean Recommendations for the Application of Metal Sheeting Acting as a Diaphragmand the maximum horizontal displacement of the structure is compared to the FEAresults.

Yes / Fuzzy data-driven reliability analysis has been used in different safety-critical domains for risk assessment and decision-making where precise failure data is non-existent. Expert judgements and fuzzy set theory have been combined with different variants of fault trees as part of fuzzy data-driven reliability analysis studies. In such fuzzy fault tree analyses, different people represented failure data using different membership functions for the fuzzy set, and different parameters were set differently in the expert opinion elicitation process. Due to the availability of a wide variety of options, it is possible to obtain different outcomes when choosing one option over another. This article performed an analysis in the context of fuzzy data-based temporal fault tree analysis to investigate the effect of choosing different membership functions on the estimated system reliability and criticality ranking of different failure events. Moreover, the effect of using different values for the relaxation factor, a parameter set during the expert elicitation process, was studied on the system reliability and criticality evaluation. The experiments on the fuel distribution system case study show system reliability did not vary when triangular and trapezoidal fuzzy numbers were used with the same upper and lower bounds. However, it was seen that the criticality rankings of a couple of events were changed due to choosing different membership functions and different values of relaxation factor