Orientador : Jose Luiz Boldrini / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Científica / Made available in DSpace on 2018-07-14T23:56:28Z (GMT). No. of bitstreams: 1 Manzolli_Jonatas_M.pdf: 2562985 bytes, checksum: 6f4477cbfefbef54f70579ff50c907d0 (MD5) Previous issue date: 1988 / Resumo: Não informado / Abstract: Not informed / Mestrado / Mestre em Matemática

Orientador: Jacques Marie Edme Vielliard / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Artes / Made available in DSpace on 2018-08-04T16:35:46Z (GMT). No. of bitstreams: 1 SouzaFilho_NilsonEvilasiode_M.pdf: 2433772 bytes, checksum: 78d848f98ed9323710a846e64e57312b (MD5) Previous issue date: 2004 / Resumo: Baseando-se em estudos sobre o repertório vocal da espécie Turdus rufiventris (Aves, Passeriformes, Turdinae), o objetivo nesta pesquisa é elaborar um método para classificação semi-automática de notas (unidades contínuas de som) baseado em cálculos de correlação aplicados a imagens, cuja técnica é conhecida como "Template Matching". Como se trata de imagens espectrográficas, o método foi chamado de SITM ("SpectrographicImage Template Matching").Essa técnica de comparação de imagens está sendo incorporada como tIIIiaforma compacta de análise bioacústica, facilitando o cálculo de parâmetros relacionados à teoria da comunicação.A avaliação de desempenho do SITM foi realizada com a utilização de gravações do canto de três indivíduos da espécie T. rufiventris obtidas na natureza, e depositadas no Arquivo Sonoro Neotropical (ASN) da Universidade Estadual de Campinas - UNICAMP. Os resultados demonstraram que o SITM reconhece corretamente, com uma confiança de 96%, de 77% a 97% das notas do indivíduo 08, de 64% a 82% das notas do indivíduo 15 e de 74% a 97% das notas do indivíduo 26. Esses resultados apresentaram intervalos de confiança significativos, entretanto não o suficiente para que o SITM possa ser utilizado.em laboratório. Como os erros ocorridos no processo da pesquisa podem ser corrigidos no futuro, o' SITM pode se tomar um método muito eficaz. Otimizando o algoritmo de classificação e utilizando-se novos recursos é possível criar um software científicomodernona área de bioacústica / Abstract: Based on studies of vocal repertoire of the Rufous-bellied Thrush Turdus rufiveniris (Aves, Passerifonnes, Turdinae), the objective in this research is to elaborate a method for semi-automatic c1assification of the songs notes (continuous units of sound). This research is based on calculations of correlation applied to images; through the technique know as Template Matching. As it deals with spectrographic images, the method was called SITM (Spectrographic Image Template Matching). This technique of comparison of images is begging incorporated into a compact fonn of bioacustic anaIysis, faciIitating the calculation of parameters related to the theory of communication. The evaluation of perfonnance of SITM was carried out using songs of three individuaIs of T. rufiventris, recorded in the wild and deposited in the Neotropical Sound Archive (ASN) of the State University of Campinas (UNICAMP), Brazil. The results had demonstrated that SITM recognizes correct1y,with a 96% confidence, 77 to 97% of the notes of individual 08, 64' to 82% of the notes of individual 15 and 74 to 97% of the notes of individual 26. These results are that occurred in this process can be corrected in the future, when SITM can become a very efficient method. Optimizing the c1assificationalgorithm and using new tools, it will be possible to create modem scientific software in the biocustic area / Mestrado / Mestre em Multimeios

From the requirements of the Ionosonde digitisation project, undertaken by Rhodes University Antarctic Research Group, it was decided to use the Fast Fourier Transform to compute the spectrum analysis. Several FFT algorithms are reviewed and properties discussed, and the Ccoley Tukey algorithm chosen for utilization. The hardware implementation of this algorithm, and the microprogram control of the whole system are discussed in detail, and such design aspects that required computer simulation are also treated in detail. The final testing of the analyser is shown, and includes a test using data from an ionosonde sounding. The conclusions contain details of extensions to the analysers present operation, required by plans to place the whole Chirpsounder under microprocessor control

The aim of this work was to assess the potential of FTIR spectroscopy in the analysis of the cis and trans fatty acid contents of fats and oils. Preliminary studies on the liquid and solution phase spectra of individual FAME'S (fatty acid methyl esters), and on mixtures of FAME'S, were conducted to establish whether spectral features enhanced by FTIR could be used to provide improved methods of determining cis and trans contents. A number of previously unreported bands and spectral features associated with the cis and trans isolated double bond(s) were discovered. None of the trans bands were considered suitable for quantitation, however, methods of determining the cis content were developed, based on the the two bands listed below. These methods were compared with current IR methods, and with a capillary GC method. (a) The CIS C=C stretching band (1654 cm-1). (b) An unassigned band at 913 cm-1, observed only in the spectra of non-conjugated di- and tri-unsaturated FAME'S. All the established methods as well as those developed in this work, for the quantitative analysis of FAME'S have inherent disadvantages. For example, with the capillary GC method, difficulties are encountered in resolving and identifying samples containing complex mixtures of isomers. With the IR techniques, the difficulties involve the elimination of interfering bands, and the absorbance of similar fatty acids at the same frequencies. The application of GC-FTIR was seen as a logical extension of this project, because it offered a great potential for the separation and charactisation of components of complex mixtures. Studies conducted on vapour phase spectra showed that the identification of many FAME'S could be ascertained from various band ratios. Furthermore, band ratios could be used to quantify the cis/trans content of co-eluting isomers. Different types of capillary columns were tried, and optimum conditions established where possible.

The discrete Fourier transform in Cartesian coordinates has proved to be invaluable in many disciplines. However, less theory has been developed for functions that are best described in polar coordinates. In this thesis, a new discrete 2D-Fourier transform in polar coordinates is proposed and tested by numerical simulations. Guidelines for choosing sample size are developed. Furthermore, to be as useful as its Cartesian counterpart, improvements are made to reduce the computing time.

D.Phil. (Electrical & Electronic Engineering Science) / Recent advancement in optical fibre communications technology is partly due to the advancement of optical thin-film technology. The advancement of optical thin-film technology includes the development of new and existing deposition and optical filter design methods. Genetic algorithm is one of the new design methods that show promising results in designing a number of complicated design specifications. The research is entirely devoted to the investigation of the genetic algorithm design method in the design of producible polarised and non-polarised edge filters for optical fibre communication applications. In this study, a number of optical filter design methods such as Fourier Transform and refining are investigated for their potential in designing those kinds of structures. Owing to the serious limitations to which they are subject, they could not yield the kind of results anticipated. It is the finding of this study that the genetic algorithm design method, through its optimisation capability, can give reliable and producible designs. This design method, in this study, optimises the thickness of each layer to get to the best possible solution. Its capability and unavoidable limitations in designing polarised and non-polarised beam splitters, edge filters and reflectors from absorptive and dispersive materials are well demonstrated. It is observed that the optical behaviour of the non-polarised filters designed by this method show a similar trend: as the angle of incidence increases the inevitable increase in the percentage of polarisation, stop bandwidth and ripple intensity is well controlled to an acceptable level. In the case of polarised designs the S-polarised designs show a better response to the optimisation process than the P-polarised designs, but all of them are kept well within an acceptable level. It is also demonstrated that polarised and non-polarised designs from the genetic algorithm are producible with great success. This research has accomplished the task of formulating a computer program using genetic algorithm in a Mathlab® environment for the design of producible polarised and non-polarised filters from materials of absorptive and dispersive nature.

Proportional, Integral and Derivative feedback control (PID) is a mature technology responsible for the majority of automated decision making in the process industry. Despite the high reliance on this technology, low levels of maintenance and performance measurement are the norm in the process industry. Several analysis techniques exist for identifying oscillation, and then highlighting the root cause of the problem. Several time and frequency domain statistical techniques, as well as wavelet analysis are used to diagnose loop performance. In this study, 127 different control loops are analysed, and in depth troubleshooting is performed on a selection of 18 different control loops. The performance of flow loop F1035 is tracked through a number of different analysis techniques, highlighting the pitfalls of using only a single analysis technique. Lower order statistics and minimum variance performance analysis show that the loop is performing well. Plotting the PV-OP relationship suggests non-linear tendencies on F1035, and this is corroborated using high order statistical analysis (bicoherence). Non-linear loop behaviour is often as a result of a slip stick cycle, a sign that valve maintenance may be required. Frequency (power spectrum) analysis shows a 43 minute dominant oscillation, suggesting a low frequency disturbance affecting loop performance. Process units are typically exposed to cyclic behaviour occurring at several different frequencies, each having a different effect on the control of the process. By using a frequency based approach based on sinusoidal basis functions (ie Fourier analysis), these different frequencies get aggregated. This smudging of specific frequency information makes it difficult to pin-point the root cause, and makes the grouping of common oscillations difficult. In order to address the above issue, F1035 is analysed using othornormal wavelet basis functions. The results show that the period of oscillation is affected between day and night, with roughly a 2 minute oscillation prevalent at mid night, compared to a 100 minute oscillation at mid day. Obviously the 12 hour day-night swing is also prevalent. This information is unique to this approach. Ways of visualising changes in oscillatory behaviour using the wavelet analysis are also presented. Technical analysis of controller performance is only a small subsection of the issues that need to be considered when implementing a loop monitoring and maintenance solution. Issues such as connectivity, configuration, analysis, reporting and auditing are key in designing a workable maintenance environment for PID loop maintenance. Several packages are available commercially to assist industry in performing loop maintenance. When evaluating which package is best suited to a specific requirement, it is important to consider several different issues. The different audiences with a vested interest in loop performance require special attention in terms of reporting requirements. Visualisation of results is often more important than the physical measure of performance. Finally, the ability of a company to benchmark itself against current best practices and performance is often perceived as a major advantage. The results presented and discussed were generated using real industrial data. Information regarding suggested best practice when evaluating commercially available products is based largely on the author’s personal experience in the large scale industrial installation of such a monitoring solution. / Dissertation (MEng (Process Control))--University of Pretoria, 2007. / Chemical Engineering / unrestricted

No description available.

This study focuses on the characterization of InAs and InAs1-xSbx epitaxial layers by infrared reflectance and transmittance spectroscopy and Hall measurements. Reflectance measurements were performed in order to obtain the dielectric parameters and to extract from these information about the electrical properties (mobility and carrier concentration) of this important III-V material system. The transmittance measurements were used to determine the bandgap of InAsSb. Infrared reflectivity and transmittance measurements were performed in the wavelength range 200 – 2000 cm-1 on InAs and InAsSb layers grown on three types of substrates. A classical two oscillator model that takes into account both the free carriers and the lattice, was used to analyse the reflectance data using the BMDP® computer curve fitting software. The dielectric parameters and the electrical properties (carrier concentration and mobility) were extracted from the simulations. Due to the low free carrier concentration in the epitaxial structures, the plasma resonance frequency (ωp) values obtained from the simulations of reflectance spectra measured above 200 cm-1, were in the order of 20-30 cm-1. These low values were confirmed by direct measurements of ωp in reflectance spectra obtained in the range 15-200 cm-1. The simulated carrier concentration and mobility values determined optically were compared to the values determined by Hall measurements at room temperature and previously reported values by other researchers. The simulated values obtained were in reasonable agreement with the Hall values. The simulated and measured carrier concentrations obtained for InAs layers were significantly higher than the intrinsic carrier concentration for InAs at room temperature, indicating notable concentrations of donors resulting from the growth process.

Orientador : Jose Pissolato Filho / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica / Made available in DSpace on 2018-07-18T14:11:26Z (GMT). No. of bitstreams: 1 Fraga_JoseRenatoCastroPompeia_M.pdf: 3734946 bytes, checksum: ed4c792995667d2bd89597fd918b8eb9 (MD5) Previous issue date: 1993 / Resumo: Este trabalho apresenta o desenvolvimento de um programa computacional para análise de transitórios eletromagnéticos em linhas de transmissão. Desenvolve-se a formulação das equações da linha de transmissão no domínio da frequência e posteriormente é feita uma transformação para o domínio Z, que facilita o tratamento dos parâmetros da linha, os quais são dependentes da frequência. Além disso, a forma das equações no domínio Z, possibilita uma transformação direta no domínio do tempo. Depois do equacionamento é desenvolvido o programa computacional baseado na solução de sistemas de equações de tensão nodal, assim como o equacionamento dos parâmetros concentrados da linha. Finalmente são apresentados os resultados provenientes da aplicação deste método. Estes resultados são confrontados com os resultados obtidos com a utilização de outros métodos exitentes e já validados. A partir desta análise comparativa, pode-se avaliar o desempenho superior do programa computacional, com relação a tempo de simulação e precisão dos resultados / Abstract: This work presents the development of a computer program for electromagnetic transient analysis at transmission lines. The equations for the transmission line are developed in the frequency domain, and afterwards,a transformation to Z Domain is done, which eases the treatment of the line parameters which. are frequency dependent. Besides, the Z Domains equations format make possible a direct transformation to time domain. After this formulation, a computer program based on nodal voltage equation systems solution is developed, as weIl as the formulation of the line lumped parameters. Finally, the results originated from the method's application are presented. From this comparative analisys, it was possilble to evaluate the improved computer program performance, with relation to simulation time and results precision / Mestrado / Mestre em Engenharia Elétrica