A 4 bit, Rom-Less Direct Digital Frequency Synthesizer (DDFS) is designed in 65nm CMOS technology. Interleaving with Return-to-Zero (RTZ) technique is used to increase the output bandwidth and synthesized frequencies. The performance of the designed synthesizer is evaluated using Cadence Virtuoso design tool. With 3.2 GHz sampling frequency, the DDFS achieves the spurious-free dynamic range (SFDR) of 60 dB to 58 dB for synthesized frequencies between 200 MHz to 1.6 GHz. With 6.4 GHz sampling frequency, the synthesizer achieves the SFDR of 46 dB to 40 dB for synthesized frequencies between 400 MHz to 3.2 GHz. The power consumption is 80 mW for the designed mixed-signal blocks.

The objective of this thesis is to design and implement a velocity-stabilizing driver for permanent magnet synchronous motor. The research presents how to achieve high efficiency in stabilizing overall velocity for a permanent magnet synchronous motor. In order to drive the integral system, there are six steps square-wave starting device, sine-wave driver, estimation of magnetic angle, velocity feedback and current feedback control circuits designed. A test platform is built by Microchip-made dsPIC33FJ128MC804 digital signal processor used as a control core. ¡§Simulink¡¨ simulator is used during the laboratory test. The simulation results are compared with those of experiments in order to verify the achievement of excellent performance of Robust Integral Velocity-stabilizing Controller on Permanent Magnet Synchronous Motor Driver.

<p>Fluid simulating is one of the most difficult problems in computer graphics. On the other hand, water appears in our life very frequently. This thesis focuses on water simulating. We have two main methods to do this in the thesis: the first is wave based water simulating; Sine wave summing based and Fast Fourier Transform based methods are all belong to this part. The other one is physics based water simulating. We make it based on Navier-Stokes Equation and it is the most realistic animation of water. It can deal with the boundary and spray which other method cannot express. Then we put our emphasis on implement by the physics method using Navier-Stokes Equation.</p>

The theory describing the scaling properties of quantum field theory is introduced. The symmetry principles behind scale and conformal transformations are reviewed together with the renormalisation group. A method for improving perturbative calculations of physical quantities in the infra-red limit is developed using general analyticity properties valid for all unitary quantum field theories. The infra-red limit of a physical quantity is shown to equal the limiting value of the Borel transform in a complex scale parameter, where the order of the Borel transform is related to the domain of analyticity. It is shown how this general result can be used to improve perturbative calculations in the infra-red limit. First, the infra-red central charge of a perturbed conformal field theory is considered, and for the unitary minimal models perturbed by ɸ(1,3) the developed approximation is shown to be very close to the exact results by improving only a one loop perturbation. The other example is the infra-red limit of the critical exponents of x(^4) theory in three dimensions, where our approximation is within the limits of other approximations. The exact renormalisation group equation is studied for a theory with exponential interactions and a background charge. It is shown how to incorporate the background charge, and using the operator product expansion together with the equivalence between the quantum group restricted sine-Gordon model and the unitary minimal models perturbed by ɸ(1,3), the equation obtained is argued to describe the flow between unitary minimal models. Finally, a semi-classical approximation of the low energy limit of a bosonic membrane is studied where the action is taken to be the world-volume together with an Einstein-Hilbert term. A solution to the linearized equations of motion is determined describing a membrane oscillating around a flat torus.

In Introduction, we review integrable and topological solitons. In Numerical Methods, we describe how to minimize functionals, time-integrate configurations and solve eigenvalue problems. We also present the Simulated Annealing scheme for minimisation in solitonic systems. In Classical Aspects, we analyse the effect of the potential term on the structure of minimal- energy solutions for any topological charge n. The simplest holomorphic baby Skyrme model has no known stable minimal-energy solution for n > 1. The one-vacuum baby Skyrme model possesses non-radially symmetric multi-skyrmions that look like 'skyrmion lattices' formed by skyrmions with n = 2. The two-vacua baby Skyrme model has radially symmetric multi- skyrmions. We implement Simulated Annealing and it works well for higher order terms. We find that the spatial part of the six-derivative term is zero. In Quantum Aspects, we find the first order quantum mass correction for the Ф(^4) kink using the semi-classical expansion. We derive a trace formula which gives the mass correction by using the eigenmodes and values of the soliton and vacuum perturbations. We show that the zero mode is the most important contribution. We compute the mass correction of Ф(^4) kink and Sine-Gordon numerically by solving the eigenvalue equations and substituting into the trace formula.

Vibration generated from various sources (engine, road surface, tires, exhaust, etc.) should be considered in the design of a car body. These vibrations travel through transfer systems (drivetrain, suspension, body, etc.) to the steering wheel, seats and other areas where it is detected by the passengers of the vehicle. Transmission routes must be studied and efforts made to keep transfer systems from amplifying vibration and to absorb it instead. Since the superior vibration transfer system is the car body, finite element analysis and experimental vibration analysis are performed on car body-in-white. Body vibration analysis entails understanding and improving the body&rsquo / s dynamic characteristics that act as vibration transfer channels. In the previous study, a finite element model has been created for a car body-in-white available in Automotive Laboratory (Mechanical Engineering Department, Middle East Technical University, Ankara) and its natural frequencies and mode shapes have been determined using finite element analysis software. In this study, vibration tests have been performed on actual car body-in-white. Frequency response functions between 34 response locations and force application point have been measured. Using these frequency response functions, natural frequencies and mode shapes of the body-in-white have been determined. Finite element analysis and experimental results have been compared to evaluate the finite element model reliability.

p. 1 - 117 / Submitted by Santiago Fabio (fabio.ssantiago@hotmail.com) on 2013-01-28T20:00:05Z No. of bitstreams: 2 Cleyton Miranda Barros - Texto.pdf: 694417 bytes, checksum: d772db4f8eddb8f9a6ab03775e730f4f (MD5) Cleyton Miranda Barros - PRE.pdf: 63059 bytes, checksum: 30adf19cb58643dbedfe6bc1daf30346 (MD5) / Approved for entry into archive by Fatima Cleômenis Botelho Maria (botelho@ufba.br) on 2013-01-30T13:03:19Z (GMT) No. of bitstreams: 2 Cleyton Miranda Barros - Texto.pdf: 694417 bytes, checksum: d772db4f8eddb8f9a6ab03775e730f4f (MD5) Cleyton Miranda Barros - PRE.pdf: 63059 bytes, checksum: 30adf19cb58643dbedfe6bc1daf30346 (MD5) / Made available in DSpace on 2013-01-30T13:03:19Z (GMT). No. of bitstreams: 2 Cleyton Miranda Barros - Texto.pdf: 694417 bytes, checksum: d772db4f8eddb8f9a6ab03775e730f4f (MD5) Cleyton Miranda Barros - PRE.pdf: 63059 bytes, checksum: 30adf19cb58643dbedfe6bc1daf30346 (MD5) Previous issue date: 2007 / Esta dissertação analisa o desempenho do Sistema Nacional de Emprego – SINE no Estado da Bahia, com enfoque na atividade de intermediação de mão-de-obra, para o período de 2001 a 2005. A partir de uma pesquisa documental, analisou-se os resultados apresentados por esta política pública de emprego, tendo como referência a dinâmica do mercado formal de trabalho no estado. Para tanto, considerou-se diferentes dimensões da política de intermediação, a exemplo do perfil dos trabalhadores atendidos, bem como da relação entre esses e o universo de trabalhadores admitidos e desligados no período, segundo dados do Cadastro Geral de Empregados e Desempregados – CAGED. Como resultado, constatamos uma correlação positiva entre o desempenho do mercado formal de trabalho e o desempenho do SINE, através da relação entre número dos trabalhadores colocados no mercado formal de trabalho através do serviço de intermediação de mão-de-obra em relação ao número total de admissões. Além disso, verificamos ainda que o desempenho do serviço público de intermediação de mão-de-obra é bastante heterogêneo, com expressivas variações de acordo com o perfil dos trabalhadores. / Salvador

The main focus of my dissertation is the Modified Stochastic Sine-Gordon Equation: utt = 2uxx − ut − sin(|u|^(&gamma)) + b(u, du/dt)dW/dt where &gamma > 0 is the parameter of the power of non-linearity, &delta &ge 0 is the magnitude of non-linearity, &alpha> 0 be the damping parameter, and &sigma the diffusion intensity, on one dimensional domain. We analyze the properties of the solution of the SPDE by the eigenfunctions approach allowing us to truncate the infinite-dimensional stochastic system (i.e the SDEs of Fourier coefficients related to the SPDE), to control its energy, existence, uniqueness, continuity and stability. The analysis relies on the investigation of expected Lyapunov functional of the energy in terms of all system-parameters. We simulate the model with respect to all system-parameters to visualize our conclusions.

Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2016-12-16T11:58:30Z No. of bitstreams: 1 PDF - Maynne Santos de Oliveira.pdf: 1942630 bytes, checksum: 9af0056da43e742cc0fe10b3412b867b (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2017-02-02T18:22:42Z (GMT) No. of bitstreams: 1 PDF - Maynne Santos de Oliveira.pdf: 1942630 bytes, checksum: 9af0056da43e742cc0fe10b3412b867b (MD5) / Made available in DSpace on 2017-02-02T18:22:42Z (GMT). No. of bitstreams: 1 PDF - Maynne Santos de Oliveira.pdf: 1942630 bytes, checksum: 9af0056da43e742cc0fe10b3412b867b (MD5) Previous issue date: 2016-08-18 / Conselho Nacional de Desenvolvimento Científico e Tecnológico - CNPq / Brazilian labor market is characterized by a strong heterogeneity, since the beginning of its structuring. The severity of the Brazilian unemployment problem has intensified since the 1990s, when thousands of jobs were reduced, excluding a large number of workers from the formal labor market and making them look for livelihood solutions in precariousness and in informality. In this way, the governors presented proposals and put into practice policies aimed at employment and income generation, which act to reduce the rates of unemployment, precariousness and informality in the country until the present day. In this context, the National Employment System (SINE), created in 1975, was created to combat labor market deficiencies, offering free services to the general population, who wish to (re)enter the formal market through labor intermediation, among other services offered. In this sense, this study verifies the performance of the municipal SINE as a labor intermediator in Campina Grande - PB, evaluating the profile of the unemployed workers who attend the institution in the city. For that, a field research was carried out through a questionnaire applied to a sample of unemployed workers, users of SINE services. The results allowed a deepening on the performance of the entity to tackle its propositions, as well as concludes that the Municipal SINE has deficiencies. In addition, suggestions and improvements have been made, enabling the institution to better analyze its demand for workers, seek advances in the areas of labor intermediation, and provide professional qualification courses that are better suited to the profile of the city workers. / O mercado de trabalho brasileiro é marcado por uma forte heterogeneidade, desde o início da sua estruturação. A gravidade do problema do desemprego no Brasil intensificou-se a partir da década de 1990, quando milhares de postos de trabalho foram reduzidos, excluindo uma grande quantidade de trabalhadores do mercado de trabalho formal e fazendo com que estes buscassem soluções de subsistência na precarização e na informalidade. Desta forma, os governantes apresentaram propostas e colocaram em prática políticas voltadas para a geração de emprego e renda, que atuam na redução das taxas de desemprego, precarização e informalidade no país, até os dias atuais. Neste contexto, o Sistema Nacional de Emprego – SINE, criado em 1975, surgiu com o objetivo de combater as deficiências do mercado de trabalho, oferecendo serviços gratuitos a população, no geral, que desejam (re) inserir-se no mercado formal, através da intermediação da mão de obra, entre outros serviços oferecidos. Neste sentido, este trabalho consiste em um estudo para verificar a atuação do SINE municipal como intermediador de mão de obra, em Campina Grande-PB, avaliando qual é o perfil dos trabalhadores desempregados que frequentam a instituição no município. Para tanto, foi desenvolvida uma pesquisa de campo, realizada através de um questionário aplicado a uma amostra dos trabalhadores desempregados que procuram o SINE. Os resultados obtidos possibilitaram um aprofundamento sobre a atuação do órgão frente as suas proposições, bem como conclui que o SINE Municipal apresenta deficiências. Ademais, foram apresentadas sugestões e melhorias para que a instituição analise melhor a sua demanda de trabalhadores, busque avanços nos âmbitos da intermediação de mão de obra e forneça cursos de qualificação profissional que sejam mais adequados ao perfil da força de trabalho campinense.

Structural Health Monitoring (SHM) techniques are widely used in a number of Non – destructive Evaluation (NDE) applications. There is a need to develop effective techniques for SHM, so that the safety and integrity of the structures can be improved. Two most widely used SHM methods for plates and rods use either the spectrum of the impedances or monitor the propagation of lamb waves. Piezoelectric wafer – active sensors (PWAS) were used for excitation and sensing. In this study, surface response to excitation (SuRE) and Lamb wave propagation was monitored to estimate the integrity of the round objects including the pipes, tubes and cutting tools. SuRE obtained the frequency response by applying sweep sine wave to surface. The envelope of the received signal was used to detect the arrival of lamb waves to the sensor. Both approaches detect the structural defects of the pipes and tubes and the wear of the cutting tool.