Neste trabalho se apresenta o desenvolvimento de algoritmos hermitianos de integração das equações diferenciais do filtro digital de Butterworth mediante operadores de integração numérica de ordem elevada com passo único. A teoria do filtro de Butterworth é apresentada mediante o emprego da transformada de Fourier. Exemplos de aplicação apresentados através destes algoritmos mostram que os resultados são, como esperado, mais precisos que os resultantes dos métodos usuais presentes na literatura especializada / In this work is presented the development of hermitian algorithm for integration of the Butterworth digital filter’s differential equations by means of high order numerical one step operators. The Butterworth filter’s theory is presented based on the Fourier transform. Numerical examples show that the results of the developed hermitian algorithm are more accurate than the usual methods present in the specialized literature, as expected

Information is often stored and transmitted through electrical signals. This information may need refinement, which may be done by processing and altering the electrical signals, in which it is transmitted. When refining a signal, a frequency selective filter is often used. It can be implemented through digital signal processing (DSP). DSP is a concept where signals are refined using a digital compute system. Digital systems are designed to replace their analog counterpart, mitigating their flaws in scalability, complexity and cost. A DSP system is typically implemented using software on a small computer, while analog systems are implemented through various electronic components. The objective of this project is to design a DSP system that filters analog input data using automatically synthesised filters from user-defined input specifications. The DSP system is implemented using a microcontroller. The system designed the filters and found the filter coefficients. It then uses analog to digital converter (ADC) to sample an input signal and applies the filter. Lastly, it uses the digital to analog converter (DAC) to reconstruct a filtered, analog result. A user interface is not designed for the system, and only a limited number of filters are implemented. However, the system is successful in designing filters and finding their coefficients.

<p>This thesis was done at DaimlerChrysler AG in Stuttgart,Germany. The aim of the thesis is to develop an algorithm for controlling a motor used in a Shift-by-Wire System. The control algorithm is to be implemented in a prototype car for further testing. The Shift-by-Wire System can be described as follows: An electrical actuator is mounted in an automatic gearbox to select gears instead of the gear stick. The actuator is controlled by a microcontroller, which runs a control algorithm. The position of the actuator is measured with a linear position sensor and sent to the controller.</p>

Avionics Division of Saab AB develops advanced electronics that need to be robust and work in harsh environments with for example extreme temperatures and cosmic radiation without any failure. To succeed with this the electronics need to be simulated and tested. Therefore this thesis work is done to strengthen the Avionics Division’s knowledge of hardware modelling and simulation by evaluating the simulation tools LTSpice, PSpice and SystemVision, their functions and capabilities. In this thesis a survey is carried out with help of a questionnaire to study the Avionics Division’s needs for simulation. The survey is underlying an analysis of the analyses that can be performed by the simulation tools for example Sensitivity analysis, Worst Case analysis, Monte Carlo analysis and Parametric Sweep analysis. The different analyses are discussed in the thesis. The questionnaire is also underlying an analysis of the tools LTSpice, PSpice and SystemVision. The result of the analysis is summarized in Table 1. A case study of a circuit simulation in SystemVision, based on an existing circuit used by Avionics Division, is also done within this thesis work. The study is done to evaluate the tool’s usability, to see if it is easy to perform a simulation and if it is easy to find and use suitable models from the model library. The case study describes how a simulation is performed in SystemVision and how an AC analysis of a Butterworth filter is done. A stability and reliability check of the tool is performed as well as a robustness simulation. The analyses were easy to do and the overall impression is that SystemVision is reliable and user friendly structured. In order to check and compare the results of the AC analysis the same analysis is performed using LTSpice. The comparison shows that the results differ. This depending on that the models of the circuit were some what different in LTSpice and SystemVision. The final conclusion is that SystemVision would fit within Avionics Division’s workflow. Using SystemVision demands education of the engineers to secure maximum use of all the advantages of SystemVision.

This thesis was done at DaimlerChrysler AG in Stuttgart,Germany. The aim of the thesis is to develop an algorithm for controlling a motor used in a Shift-by-Wire System. The control algorithm is to be implemented in a prototype car for further testing. The Shift-by-Wire System can be described as follows: An electrical actuator is mounted in an automatic gearbox to select gears instead of the gear stick. The actuator is controlled by a microcontroller, which runs a control algorithm. The position of the actuator is measured with a linear position sensor and sent to the controller.

A Shropshire Lad by English composer George Butterworth (1885-1916) is a song cycle composed by adopting six poems of the same title ¡§A Shropshire Lad¡¨ by Alfred Edward Housman (1859-1936). These poems depict the life of a pure young man, which passes through love, separation, and death by symbolical and sarcastic writing skill, and the composer composed the songs exquisitely, creating these six songs with different styles, and presenting his ingenious conception within the music and lyrics. The study has five major components: an introduction to the composer, George Butterworth; the art songs of George Butterworth; an introduction to the poet Alfred Edward Housman; the composing background of A Shropshire Lad, and the analysis as well as interpretation of six-songs of A Shropshire Lad. It is hoped that through this study, singers can have a better understanding of the hidden meaning of the poems and of how composers use music to express the wonders of poetry. They can then in turn interpret this song cycle in the most apposite mood and with the most appropriate way of singing.

The METU Gait Analysis System employs a computer program called Kiss-GAIT for the calculation of joint angles, moments and powers using force plate data and marker trajectories as input. Kiss-GAIT was developed using Delphi and is confined to calculations related to the standard gait protocol. Because the code lacks the flexibility required to carry out various test cases, the inverse dynamics formulation being used could not be verified and the extent of the error propagation problem could not be determined so far. The first aim of this study was to develop a code for the inverse dynamics model of the METU Gait Analysis System making use of the flexible programming environment provided by MATLAB. Verified and more reliable analysis results, obtained by reformulating the inverse dynamics algorithm in a new code, are presented. Secondly, data smoothing and differentiation techniques conventionally used in gait analysis were critically reviewed. A common tool used for filtering marker trajectories is the Butterworth digital filter. This thesis presents a modified, adaptive version of this classical tool that can handle non-stationary signals owing to its coefficients which are functions of local signal structure. The results of this thesis indicate the dominancy of ground reactions as compared to inertial effects in normal human gait. This implies that the accuracy needed in body segment inertial parameter estimation is not a critical factor. On the other hand, marker trajectories must be as accurate as possible for meaningful kinetic patterns. While any smoothing and differentiation routine that produces reasonable estimates is sufficient for joint moment calculation purposes, the estimation performance becomes a key requirement for the calculation of joint powers.

The present thrust in the electronics industry towards integrating multiple functions on a single chip while operating at very high frequencies has highlighted the need for efficient Electronic Design Automation (EDA) tools to shorten the design cycle and capture market windows. However, the increasing complexity in modern circuit design has made simulation a computationally cumbersome task. The notion of model order reduction has emerged as an effective tool to address this difficulty. Typically, there are numerous approaches and several issues involved in the implementation of model-order reduction techniques. Among the important ones of those issues is the problem of determining a suitable order (or size) for the reduced system. An optimal order would be the minimal order that enables the reduced system to capture the behavior of the original (more complex and larger) system up to a user-defined frequency. The contribution presented in this thesis describes a new approach aimed at determining the order of the reduced system. The proposed approach is based on approximating the impulse response of the original system in the time-domain. The core methodology in obtaining that approximation is based on numerically inverting the Laplace-domain of the representation of the impulse response from the complex-domain (s-domain) into the time-domain. The main advantage of the proposed approach is that it allows the order selection algorithm to operate directly on the time-domain form of the impulse response. It is well-known that numerically generating the impulse response in the time-domain is very difficult and its not impossible, since it requires driving the original network with the Dirac-delta function, which is a mathematical abstraction rather than a concrete waveform that can be implemented on a digital computer. However, such a difficulty is avoided in the proposed approach since it uses the Laplace-domain image of the impulse response to obtain its time-domain representation. The numerical simulations presented in the thesis demonstrate that using the time-domain waveform of the impulse response, computed using the proposed approach and properly filtered with a Butterworth filter, guides the order selection algorithm to select a smaller order, i.e., the reduced system becomes more compact in size. The phrase "smaller or more compact" in this context refers to the comparison with existing techniques currently in use, which seek to generate some form of time-domain approximations for the impulse response through driving the original network with pulse-shaped function (e.g., Gaussian pulse).

Uno de los objetivos principales que se plantea en cualquier campo, tanto en investigación como en la clínica, consiste en lograr la estandarización de estudios para así poder obtener conclusiones generales, poder determinar parámetros y patrones de normalidad y, consecuentemente, determinar con precisión la patología valorando la desviación de estos índices.En los estudios renográficos, una función que posibilita esta estandarización es la función de retención renal que representa la fracción de trazador que es retenida en el riñón, a través del tiempo, como respuesta a una entrada instantánea en forma de bolo radiactivo si el trazador se hubiese introducido directamente en la arteria renal.Puesto que en un estudio real, la inyección se realiza en una vena periférica, la función de retención renal se ha de obtener mediante la deconvolución de la curva actividad/tiempo del área renal con la curva correspondiente a un área vascular representativa de la actividad sanguínea.El objetivo fundamental de este trabajo fue obtener un método de cálculo de la función de retención renal que incluyese una optimización en el grado de filtrado. Mediante simulación numérica de un estudio gammagráfico renal, se simularon estudios con 131I-Hippuran y 99mTc-MAG3.Mediante simulación numérica se ha demostrado la existencia de un valor mínimo en el error cuadrático medio entre las funciones de retención renal teóricas y las obtenidas mediante deconvolución. La presencia de este valor mínimo se manifiesta para los tres filtros considerados (filtro de tres puntos, filtros de Butterworth y filtro "data bounding") y para los dos trazadores, 131I-Hippuran y 99mTc-MAG3, estudiados en este trabajo.La ordenación de los tres filtros en base al valor mínimo del error cuadrático medio es: filtro de Butterworth, filtro de tres puntos y filtro "data bounding", éste con valores mucho más altos del error que los dos filtros lineales. Esta ordenación es la misma para los dos trazadores, siendo los valores del error correspondiente a 99mTc-MAG3 aproximadamente la mitad que los de 131I-Hippuran.El valor del factor de suavizado que hace mínimo el error, depende del tiempo de tránsito y de la relación señal/ruido. Se ha comprobado que para 99mTc-MAG3 el valor del suavizado que hace mínimo el error es menor que para 131I-Hippuran, lo que está de acuerdo con su mayor relación señal/ruido. Asimismo para cada trazador, se ha demostrado que la dependencia respecto al tiempo de tránsito es mayor que respecto a la relación señal/ruido. Este hecho, que se repite para los tres filtros, ha permitido obtener valores de los factores de suavizado óptimos para cada trazador como funciones del tiempo de tránsito exclusivamente. Se ha analizado el comportamiento de los tres filtros en la determinación de los parámetros de interés funcional derivados de la función de retención renal. Para ello, se modelizó la función de retención renal mediante una función de cuatro parámetros: h(t) = (A-D) / (1+t/C)**B) + D donde A corresponde a la altura de la función de retención renal par aun tiempo igual a cero, B se relaciona con la dispersión de tiempos de tránsito, C es el tiempo medio de tránsito intrarrenal y D es el valor de estabilización relacionado con una posible retención de trazador en el riñón. De este estudio se ha concluído: La estima del parámetro A es mejor para los métodos de filtrado lineales que para el no lineal, ya que proporciona información no sesgada y presenta valores del error relativo menores que para el filtro no lineal. De los filtros lineales, el algoritmo que incluye un filtro de Butterworth optimizado presenta los mejores resultados.Los resultados hallados para el parámetro B, indican que el filtro de Butterworth es el que determina mejor este parámetro, lo que se refleja en un valor medio próximo al teórico.La estima del parámetro C es mejor para los métodos de filtrado lineal que para el no lineal. En ambos, el error relativo es menor y no existe sesgo, siendo el filtro de Butterworth el que presenta los mejores resultados.Respecto al parámetro D, los valores hallados en todos los casos están muy próximos al valor teórico que es cero.En consecuencia, el método de deconvolución propuesto es el algoritmo matricial y un filtro de Butterworth optimizado en función del tiempo de tránsito.Se ha valorado la aplicabilidad del algoritmo de deconvolución en estudios reales con 131I-Hippuran. Además del filtro de Butterworth, se utilizó el filtro de tres puntos por ser el más empleado en Medicina Nuclear. De este estudio se ha concluído que los dos métodos de filtrado lineal determinan los parámetros derivados de la función de retención renal de forma equivalente. Se ha estudiado la relación existente entre las estimas del tiempo de tránsito renal y de la función renal relativa efectuadas sobre la función de retención renal, y sobre el renograma. Los resultados obtenidos al aplicar el algoritmo de deconvolución propuesto permiten concluir: El tiempo en el instante de máxima actividad en el renograma sobreestima el tiempo de tránsito renal, hecho que se comprobó que también sucedía en los estudios simulados. Se ha comprobado que esta sobrevaloración, que se acentúa para valores de tiempo en el máximo elevados, es debida fundamentalmente al valor de la constante de tiempo de la primera exponencial de la curva de aclaramiento plasmático y al grado de dispersión del tiempo de tránsito.La estima de la función renal relativa realizada sobre el renograma corregido de actividad extrarrenal da valores comparables a los obtenidos sobre la función de retención renal, no existiendo diferencias significativas.Se aplicó al algoritmo de deconvolución propuesto a estudios reales con 99mTc-MAG3. Al ser la relación señal/ruido unas tres veces mayor que la del Hippuran permitió obtener la función de retención con menor filtrado. De este estudio se ha concluído:La estima del tiempo de tránsito renal efectuada sobre el renograma como tiempo en el máximo sobrevalora el tiempo de tránsito intrarrenal en relación a la estima efectuada sobre la función de retención renal. Esta sobrevaloración es mayor para tiempos de tránsito largos.La estima de la función renal relativa realizada sobre el renograma presenta, en general, valores inferiores a los obtenidos a partir de la función de retención renal. Esto es debido a la presencia de la actividad de tipo vascular no eliminada totalmente al efectuar la corrección de la actividad extrarrenal. / The main aim of the study was to obtain a calculation method of the renal retention function which includes an optimization of the degree of filtering. Studies with (131)I-Hippuran and 99m Tc-Mag 3 were simulated by means of the numerical simulation of a renal gammagraphic study. The existence of an optimum filtering was demonstrated. This minimum value is present for the three filterings considered (smoothing, Butterworth and data bounding) and for the two tracers. Consequently the functions of the corresponding filterings were obtained. The renal retention functions were obtained and the derived parameters were calculated: relative renal function and the mean transit time. The algorithm of the deconvolution proposed consist of a matrix algorithm to perform the deconvolution and a Butterworth filtering optimized in function of renal transit time. The algorithm of deconvolution was subsequently applied to one group of renal studies with (131)I-Hippuran and to another with (99m)Tc-Mag(3) in order to assess its applicability in real cases. Likewise, we evaluated the degree of correlation between the values of the two parameters calculated on the renogram (which is normally performed in clinical practice) and those obtained from the renal retention function. For both tracers it was demonstrated the value of the transit time estimated on the renogram overestimated the value of the transit time especially in all the cases presenting renal obstruction. In the cases of (131)I-Hippuran the estimate of the relative renal function performed on the corrected renogram of the extrarrenal background gives values comparable to those obtained from the renal retention function. For the (99m)Tc-Mag(3) , the estimate carried out on the renogram yields, in general, values that are lower than those obtained from the renal retention function. This is due to the presence of the vascular background which was not wholly eliminated when correcting the renogram.

This essay is an attempt to conduct a reading of Jerusalem by Jez Butterworth through the lens of cultural materialism with John Stuart Mill’s On Liberty as intertext. The essay conducts a brief survey of previous scholarly treatment of the play, explains the theoretical background of cultural materialism that the essay operates on, and briefly introduces the intertext. The treatment itself is based around the invocation of historical and mythical roots in the play, exploring the relevant parts of the intertext, interspersed with close reading of the play itself. The essay culminates in the understanding that the climax and ending of the play is not an end to the concept of liberty evoked in the play, but that it is a call to action for it. While the play offers no unproblematic image which could guide the direction of action, it does offer liberty as a guiding principle.