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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Comparative study of the transmission ellipsometric function contours and the Smith chart

Berzett, Wade A. 05 1900 (has links)
Transmission ellipsometry is governed by the transmission ellipsometric function (TEF) of a film-substrate system. The function can be analyzed through a series of constant-thickness contours and constant-angle-of-incidence contours in the complex plane. It has been observed that these TEF contours for a zero film-substrate system bear strong resemblances to the families of curves that make up the Smith chart for transmission lines. In this thesis we present a comparative study of the TEF and the Smith chart, specifically through the distinct similarities of their respective families of curves. It is shown that both TEF and Smith chart have similar contours in both the positive and negative imaginary half planes. The Smith chart’s contours originate from a complex plane with linear boundaries. It is bisected into symmetric positive and negative imaginary half planes of equal areas that are conjugate of each other. When transformed to the Smith chart, it is normalized and the conjugate relationship remains intact. All contours in the positive imaginary half plane of the Smith chart are symmetric to all of the contours in the negative half plane of the Smith chart. TEF contours originate from a non-complex reduced thickness plane. This plane has a non-linear upper boundary. It is bisected into two equal areas but non-symmetric, half planes. When transformed to the complex τ plane, the likeness of the constant-angle-of-incidence contours and constant-thickness contours to the Smith chart contours become a function of the material indices. As the film-substrate systems material indices are increased, the range of the non-linear boundary of the ф – dr plane is reduced and the TEF contours more closely resemble the Smith chart.
122

U.S. Coast and Geodetic Survey nautical charts : a cartographic history /

McConnel, Jonathon L. January 2007 (has links) (PDF)
Thesis (M.A.)--University of Oregon, 2007. / Typescript. Includes vita and abstract. "The National Oceanic and Atmospheric Administration's Historic Maps & Chart Project ... supplied the majority of the digital images used"--P. vi. Col. ill. on folded leaves. Includes bibliographical references (leaves 186-199). Also available online via the NOAA website as PDF file, viewed 11/28/08: <http://docs.lib.noaa.gov/noaa_documents/NOAA_related_docs/McConnel_USCGS_Charts_Thesis.pdf >
123

Exploring differences in teachers', administrators', and parents' preferences for data display and whether type of graphic display influences accuracy when extracting information /

Alverson, Charlotte Y. January 2008 (has links)
Thesis (Ph. D.)--University of Oregon, 2008. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 147-151). Also available online in ProQuest, free to University of Oregon users.
124

An examination of the design and appropriate depiction of topographic information on instrument approach charts /

Mercer, David John, January 1996 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland. / Typescript. Bibliography: leaves 142-147. Also available online.
125

The relationships between spatial ability, logical thinking, mathematics performance and kinematics graph interpretation skills of 12th grade physics students

Bektasli, Behzat, January 2006 (has links)
Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 126-130).
126

U.S. Coast and Geodetic Survey nautical charts a cartographic history /

McConnel, Jonathon L. January 2007 (has links) (PDF)
Thesis (M.A.)--University of Oregon, 2007. / Title from title screen (viewed on Oct. 15, 2007). "June 2007." Includes bibliographical references (p. 186-199).
127

Software verification for programmable logic controllers

Huuck, Ralf. Unknown Date (has links) (PDF)
University, Diss., 2003--Kiel.
128

Influência da incerteza de medição no uso de cartas de controle / Influence of measurement uncertainty in the usage of control charts

Hack, Pedro da Silva January 2012 (has links)
A incerteza de medição ainda é tema de estudo e desenvolvimento, mesmo quase vinte anos após o lançamento do ISO GUM, que definiu um padrão internacional para o cálculo de incerteza. Mesmo assim, poucos estudos tratam da interface entre a incerteza de medição e outros aspectos da qualidade industrial, em especial ferramentas de controle de processo como cartas de controle. Assim, o objetivo deste trabalho é estudar os efeitos da incerteza em cartas de controle e identificar sob quais situações de aplicação ela exerce maior influência. Foi feito um mapeamento dos artigos publicados entre 2004 e 2010 sobre incerteza de medição, para identificar quais as metodologias de cálculo e abordagem são mais utilizadas. Na sequência, foi desenvolvido um método incluir nas cartas de controle a incerteza do sistema de medição, modificando as probabilidades de erros tipo I e tipo II. Finalmente, foi elaborada uma simulação computacional utilizando o método desenvolvido, para que fosse possível analisar quais as situações nas quais a incerteza de medição deve ser obrigatoriamente considerada e quais ela pode ser negligenciada. / The measurement uncertainty is still subject of study and development, even almost twenty years after the release of the ISO GUM, which set an international standard for the its calculation. Still, few studies have addressed the interface between the measurement uncertainty and other aspects of industrial quality, in particular process control tools like control charts. The objective of this work is to study the effects of measurement uncertainty on control charts and to identify the situations in which its application exerts greater influence. A research was made, mapping of the articles published between 2004 and 2010 regarding measurement uncertainty, aiming to identify which calculation methods and approaches are most widely used. After, a method was developed to include uncertainty of the measurement system in control charts, modifying the probabilities of type I and type II errors. Finally, it was created a computer simulation using the method developed, to make it possible to analyze those situations in which the measurement uncertainty must be considered and which it can be neglected.
129

Ferramentas para modelagem e monitoramento de características de qualidade do tipo taxa

Biguelini, Cecília Brasil January 2012 (has links)
Esta dissertação apresenta a modelagem e o monitoramento de características de qualidade do tipo taxa, que apresentam valores restritos ao intervalo [0,∞). A motivação inicial é que a característica de qualidade do tipo taxa pode ser modelada pela distribuição Poisson e, geralmente, a modelagem e o monitoramento não utilizam tal distribuição. Os objetivos desta dissertação são: (i) Propor uma nova carta de controle (CC), Carta Poisson, para monitorar características de qualidade do tipo taxa, com adaptação no cálculo dos limites de controle utilizando a distribuição Poisson; (ii) Propor uma CC baseada em modelo de regressão utilizando a distribuição de Poisson para monitorar características de qualidade do tipo taxa em função das variáveis de controle do processo e (iii) Propor índices de capacidade MRPOISSON Cp e MRPOISSON Cpk para avaliar processos monitorados por CCs baseadas em modelos de regressão utilizando a distribuição de Poisson. As cartas de controle e os índices de capacidade propostos foram avaliados aplicando exemplos retirados da literatura. As cartas de controle foram comparadas através do número médio de amostras (NMA) via simulação de Monte Carlo. Concluiu-se que as cartas de controle propostas são adequadas para a modelagem e o monitoramento de características de qualidade do tipo taxa pois detectaram mais rapidamente todas as alterações induzidas, apresentando melhor desempenho em comparação com outras cartas similares encontradas na literatura. / This paper presents the modeling and monitoring of quality features like rate, which have values restricted to the interval [0, ∞). The initial motivation is that the quality characteristic of the type rate can be modeled by the Poisson distribution, and generally, modeling and monitoring do not use such a distribution. The objectives of this dissertation are: (i) to propose a new control chart (CC), Poisson Charter, to monitor quality characteristics of the type rate, adapted to calculate the control limits using a Poisson distribution, (ii) propose a CC based on regression model using the Poisson distribution to monitor quality characteristics like rate as a function of the control variables of the process and (iii) Propose capability indices MRPOISSON Cp and MRPOISSON Cpk to evaluate processes and monitored by CCs based on regression models using the distribution of Poisson. The control charts and capability indices were estimated by applying the proposed examples from the literature. The control charts were compared using the average number of samples (NMA) via Monte Carlo simulation. It was concluded that the proposed control charts are suitable for modeling and monitoring of quality characteristics of the type detected faster rate because all the changes induced, showing better performance in comparison with other similar letters found in the literature.
130

Cartas de controle multivariadas baseadas no método Kernel-Statis para monitoramento de processos em bateladas

Marcondes Filho, Danilo January 2009 (has links)
Processos industriais que ocorrem em bateladas são empregados com freqüência na produção de alguns itens. Tais processos disponibilizam uma estrutura de dados bastante peculiar e, diante disso, existe um crescente interesse no desenvolvimento de cartas de controle multivariadas mais apropriadas para seu monitoramento. Destaca-se aqui uma abordagem recente que utiliza cartas de controle baseadas no método Statis. O Statis constitui-se numa técnica exploratória que permite avaliar similaridade entre matrizes de dados. Entretanto, esta técnica avalia a similaridade no contexto linear, isto é, investiga estruturas de correlação lineares nos dados. Propõe-se nesta tese a utilização de cartas de controle baseadas no Statis em conjunto com um kernel para monitoramento de processos com presença de nãolinearidades fortes. Através dos kernels, definem-se funções não lineares dos dados para melhor representação da estrutura a ser caracterizada pelo método Statis. Esta nova abordagem, denominada Kernel-Statis, é desenvolvida e avaliada utilizando dados de um processo simulado. / Industrial batch processes are widely used in the production of some items. Such processes provide a peculiar data structure; therefore, there is a growing interest in the development of customized multivariate control charts for their monitoring. We investigate a recent approach that uses control charts based on the Statis method. Statis is an exploratory technique for measuring similarities between data matrices. However, the technique only assesses similarities in a linear context, i.e. investigating structures of linear correlation in the data. In this thesis we propose control charts based on the Statis method in conjunction with a kernel for monitoring processes in the presence of strong non-linearities. Through the kernels we define non-linear functions of data for better representing the structure to be characterized by the Statis method. The new approach, named Kernel-Statis, is developed and illustrated using simulated data.

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