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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.
231

On Kalman filter implementation on FPGAs

Bhatia, Zorawar 17 December 2012 (has links)
The following dissertation attempts to highlight and address the implementation and performance of a Kalman filter on an FPGA. The reasons for choosing the Kalman filter and the platform for implementation are highlighted as well as an in depth explanation of the components and theory behind both are given. A controller system which allows the optimal performance of the Kalman filter on it is developed in VHDL. The design of the controller is dictated by the analysis of the Kalman filter which ensures only the most necessary components and operations are built into the instruction set. The controller is made up of several components including the loader, the ALU, Data RAM, KF IO, Control Store and the Branch Unit. The components working in conjunction allows the system to interface though a handshaking protocol with a peripheral of arbitrary latency. The control store is loaded with program code that is determined by converting human readable assembler into machine code through a Perl encoder. The controller system is tested and verified though an extensive testbench environment that emulates all outside signals and views internal operations. The controller system is capable of five matrix operations which are computed in parallel due to the FPGA development environment, which is far superior in this case to the alternative: a software solution, due to the vector operations inherent in the Kalman filter algorithm. The Kalman filter operation is analyzed and simulated in a MATLAB environment and this analysis confirms the need for the parallel processing power of the FPGA system upon which the controller has been built. FPGA statistical analysis confirms the successful implementation of the system meeting all criteria set at the outset of the project, including memory usage, IO usage and performance and accuracy benchmarks. / Graduate
232

Ανάπτυξη εφαρμογής για την προσομοίωση συστημάτων μεγαφώνου-ηχείου

Δάρας, Ευστάθιος 19 July 2012 (has links)
Αντικείμενο αυτής της διπλωματικής εργασίας είναι η ανάπτυξη ενός γραφικού περιβάλλοντος σε MATLAB που θα προσομοιώνει τη συμπεριφορά ηλεκτροδυναμικού μεγαφώνου τοποθετημένου σε διαφορά κουτιά της επιλογής του χρήστη. Επίσης προσομοιώνει τη συμπεριφορά του μεγαφώνου σε αντίστροφη λειτουργία, δηλαδή ως ακουστικός δέκτης (μικρόφωνο). Για την πιστοποίηση της εγκυρότητας των προσομοιώσεων έγιναν εργαστηριακές μετρήσεις, σύγκριση αυτών με τις προσομοιώσεις και στη συνέχεια μελέτη με χρήση του αναπτυχθέντος λογισμικού για διάφορες διατάξεις. / Purpose of this project is to develop a MATLAB interface in order to simulate loudspeaker behaviour mounted in various enclosures. Additionaly, the application shall simulate the inverse behaviour of a loudspeaker (as a microphone).To certify the simulations, they are compared with laboratory measurements.Finallly, various loudspeaker-enclosure systems are simulated.
233

DOCSIS 3.1 cable modem and upstream channel simulation in MATLAB

2015 December 1900 (has links)
The cable television (CATV) industry has grown significantly since its inception in the late 1940’s. Originally, a CATV network was comprised of several homes that were connected to community antennae via a network of coaxial cables. The only signal processing done was by an analogue amplifier, and transmission only occurred in one direction (i.e. from the antennae/head-end to the subscribers). However, as CATV grew in popularity, demand for services such as pay-per-view television increased, which lead to supporting transmission in the upstream direction (i.e. from subscriber to the head-end). This greatly increased the signal processing to include frequency diplexers. CATV service providers began to expand the bandwidth of their networks in the late 90’s by switching from analogue to digital technology. In an effort to regulate the manufacturing of new digital equipment and ensure interoperability of products from different manufacturers, several cable service providers formed a non-for-profit consortium to develop a data-over-cable service interface specification (DOCSIS). The consortium, which is named CableLabs, released the first DOCSIS standard in 1997. The DOCSIS standard has been upgraded over the years to keep up with increased consumer demand for large bandwidths and faster transmission speeds, particularly in the upstream direction. The latest version of the DOCSIS standard, DOCSIS 3.1, utilizes orthogonal frequency-division multiple access (OFDMA) technology to provide upstream transmission speeds of up to 1 Gbps. As cable service providers begin the process of upgrading their upstream receivers to comply with the new DOCSIS 3.1 standard, they require a means of testing the various functions that an upstream receiver may employ. It is convenient for service providers to employ cable modem (CM) plus channel emulator to perform these tests in-house during the product development stage. Constructing the emulator in digital technology is an attractive option for testing. This thesis approaches digital emulation by developing a digital model of the CMs and upstream channel in a DOCSIS 3.1 network. The first step in building the emulator is to simulate its operations in MATLAB, specifically upstream transmission over the network. The MATLAB model is capable of simulating transmission from multiple CMs, each of which transmits using a specific “transmission mode.” The three transmission modes described in the DOCSIS 3.1 standard are included in the model. These modes are “traffic mode,” which is used during regular data transmission; “fine ranging mode,” which is used to perform fine timing and power offset corrections; and “probing” mode, which is presumably used for estimating the frequency response of the channel, but also is used to further correct the timing and power offsets. The MATLAB model is also capable of simulating the channel impairments a signal may encounter when traversing the upstream channel. Impairments that are specific to individual CMs include integer and fractional timing offsets, micro-reflections, carrier phase offset (CPO), fractional carrier frequency offset (CFO), and network gain/attenuation. Impairments common to all CMs include carrier hum modulation, AM/FM ingress noise, and additive white Gaussian noise (AWGN). It is the hope that the MATLAB scripts that make up the simulation be translated to Verilog HDL to implement the emulator on a field-programmable gate array (FPGA) in the near future. In the event that an FPGA implementation is pursued, research was conducted into designing efficient fractional delay filters (FDFs), which are essential in the simulation of micro-reflections. After performing an FPGA implementation cost analysis between various FDF designs, it was determined that a Kaiser-windowed sinc function FDF with roll-off parameter β = 3.88 was the most cost-efficient choice, requiring at total of 24 multipliers when implemented using an optimized structure.
234

Análise do comportamento do centro de pressão (CoP) na posição ereta quieta em situação de aclive, declive e horizontal diante da movimentação cefálica. /

Silveira, Silvana Rocha da. January 2017 (has links)
Orientador: José Elias Tomazini / Coorientador: Everaldo de Barros / Banca: Mauro Hugo Mathias / Banca: Rita de Cassia Rigotti Vilela Monteiro / Banca: Vitor Alexandre da Silva / Banca: Elaine Cristina Martinez Teodoro / Resumo: O controle postural é um requisito imprescindível para a execução das habilidades motoras durante as tarefas das atividades de vida diária, logo, há a necessidade constante de ajuste dos segmentos corporais para garantir a autonomia e independência da mobilidade humana, dentro da conjuntura da acessibilidade. Os ajustes posturais são resultantes da interação do sistema sensório-motor e da sua correlação com o meio ambiente, produzindo orientação e estabilidade postural esperada durante a execução das atividades diárias, sendo ela estática ou dinâmica. Deste modo, o objetivo do estudo foi analisar e comparar o comportamento do centro de pressão na posição ereta quieta em situação de aclive, declive e horizontal diante da movimentação cefálica, entre três grupos com faixas etárias diferentes. O estudo transversal foi composto de 28 indivíduos, de ambos os gêneros, divididos em três grupos por faixas etárias (20 a 29 anos, 30 a 59 anos e acima de 60 anos), de acordo com os critérios de inclusão. O instrumento de avaliação constituiu-se por uma plataforma de força acoplada numa rampa com 15° e em um platô horizontal. A coleta dos dados seguiu um protocolo pré-determinado, envolvendo a posição ereta quieta com olhos abertos (OA), em quatro condições cefálicas, em três situações: aclive, declive e horizontal. Os dados obtidos foram trabalhados por meio do programa Matlab® e para a análise estatística foi aplicado o programa Action Start, utilizando a análise descritiva dos dados e ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Postural control is an essential requirement for the performance of motor skills during daily activities, so there is a constant need to adjust the body segments to ensure the autonomy and independence of human mobility, within the context of accessibility. Postural adjustments result from the interaction of the sensor - motor system and its correlation with the environment, producing orientation and postural stability expected during the execution of daily activities, being static or dynamic. Thus, the objective of the study was to analyze and compare the behavior of the pressure center in the standing upright position in slope, slope and horizontal situation in front of the head movement, between three groups with different age groups. The cross-sectional study consisted of 28 individuals of both genders, divided into three groups by age group (20 to 29 years, 30 to 59 years and above 60 years), according to the inclusion criteria. The evaluation instrument consisted of a force platform coupled on a ramp with 15 ° and a horizontal plateau. Data collection followed a predetermined protocol, involving the standing upright position with open eyes (OA), in four cephalic conditions, in three situations - slope, slope and horizontal. The data obtained were worked through the Matlab® program and for the statistical analysis the Action program was applied using descriptive data analysis and the Anova test: single factor, t-test: two samples in pairs for mean and t-test: Two samples... (Complete abstract click electronic access below) / Doutor
235

Modelamiento y Simulación de las Curvas de Elución de Proteínas a Alta Concentración en Cromatografía de Intercambio Iónico

Orellana Montecino, Camila Antonia January 2009 (has links)
Uno de los productos más atractivos de la industria biotecnológica son las proteínas que poseen propiedades especiales, tanto terapéuticas como catalíticas, pues presentan un alto valor de mercado. Para su purificación a escala industrial, los procesos cromatográficos son cada vez más utilizados, logrando separaciones en función de sus tamaños, hidrofobicidad, cargas o afinidad, siendo la cromatografía de intercambio iónico una de las más utilizadas. El escalamiento de un proceso óptimo de purificación generalmente es costoso, pues requiere de tiempo y experimentación, luego es conveniente para la industria biotecnológica reemplazar las experiencias de laboratorio por simulaciones de modelos matemáticos que entreguen los resultados en un menor tiempo y costo. El objetivo general del estudio es verificar si el modelo de balances de masa logra predecir las curvas de elución para proteínas a alta concentración en cromatografía de intercambio iónico, comparando los resultados experimentales con los simulados. Además, utilizar el modelo para encontrar la mejor estrategia de separación, reduciendo los costos y tiempo de experimentación. Se implementó el modelo de balances de masa mediante su programación en Matlab. Se utilizó la matriz aniónica Q-Sepharose FF a pH 8 y temperatura ambiente, en una columna de 1 ml, similar a las utilizadas a mayor escala. Se experimentó con tres proteínas puras y la mezcla de ellas, que presentan distintas características: α-lactoalbúmina, conalbúmina y albúmina de suero bovino, que fueron eluídas con un gradiente lineal de sal. Se calcularon los distintos parámetros del sistema con correlaciones empíricas existentes en la literatura, de los cuales se dedujo que la dispersión axial es despreciable (Pe>300) y el proceso de transferencia de masa está controlado por la difusión en la partícula (Bi>26). Los parámetros de la cinética de adsorción (α, β y Dd) fueron estimados a partir de curvas de elución obtenidas experimentalmente. Primero se determinaron los parámetros cinéticos para las proteínas puras. En este caso el modelo predice los tiempos de retención y forma de la curva de elución al cambiar condiciones de operación como flujo, pendiente del gradiente de sal en un largo fijo, concentración y volumen de la muestra. Luego se encontraron los parámetros cinéticos para las proteínas en una mezcla. Algunos de éstos fueron diferentes a los de proteínas puras por posibles efectos de competencia, desplazamiento o interacción entre las proteínas, al encontrarse en alta concentración. De esta forma el modelo logra predecir las curvas de elución de la mezcla de las tres proteínas al variar el flujo y la pendiente del gradiente de sal en un largo fijo, con errores relativos menores al 5% en el tiempo de retención de los peaks que se distinguen en la curva total. La simulación permite el cálculo del rendimiento, pureza y resolución de la separación y los peaks para cada proteína por separado. Se logró encontrar las condiciones de operación de la cromatografía de intercambio iónico y la fracción a colectar adecuadas mediante la función de costos de producción y datos de rendimiento, pureza, concentración y tiempo del proceso entregados por el programa, escogiendo el caso que presenta el mínimo costo de producción. Se cumplen los objetivos generales del trabajo pues la simulación entrega las curvas de elución en un tiempo comparablemente menor que en la experimentación (33 a 133 veces menor). Se recomienda utilizar este método como un primer paso para el escalamiento y búsqueda de condiciones de operación para cromatografía de intercambio iónico, pues solo se necesita una pequeña columna y un reducido número de experimentos para estimar los parámetros cinéticos, disminuyendo así los costos y tiempos de experimentación.
236

Modelagem em superfícies inclinadas das radiações global e difusa usando técnicas de aprendizado de máquina /

Marques, Adriano de Souza, 1975. January 2018 (has links)
Orientador: João Francisco Escobedo / Banca: Alexandre Dal Pai / Banca: José Alfredo Covolan Ulson / Banca: Valeria Cristina Rodrigues Sarnighausen / Banca: Renato Correia de Barros / Resumo: Neste trabalho é realizado um estudo para estimar a transmissividade da radiação global (Ktβh) e a fração difusa (Kdβh) incidentes em uma superfície com inclinação de 22,85° na base horária utilizando técnicas de aprendizado de máquina (TAM), a partir de dados obtidos no período de 1998 a 2001 em Botucatu/SP/Brasil. As estimativas foram realizadas usando uma série de combinações de variáveis astronômicas e geográficas por meio de três técnicas de redes neurais artificiais (RNA) do tipo Perceptron Multicamadas (MLP), Função de Base Radial (RBF) e Regressão Generalizada (GRNN) e do Sistema Adaptativo de Inferência Neuro Fuzzy (ANFIS). Como referência foram elaborados modelos estatísticos (ME) de regressão linear e polinomial. No Capítulo 1 as estimativas de (Ktβh) foram realizadas por combinações de variáveis medidas e calculadas a partir da irradiação global na superfície horizontal (HgH) e nas estimativas de (Kdβh) utilizou-se combinações de variáveis medidas e calculadas a partir de (HgH) e da irradiação global na superfície inclinada (Hgβ). No Capítulo 2 as estimativas de (Kdβh) foram realizadas por combinações de variáveis medidas e calculadas a partir das irradiações difusa (HdH) e global (HgH) obtidas na superfície horizontal. Os indicadores estatísticos r (correlação), RMSE(%) (precisão) e MBE(%) (exatidão) foram utilizados para avaliar os resultados das estimativas. No capítulo 1 os melhores resultados nas estimativas de (Ktβh) a partir das combinações realizadas com (... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In this work, a study was carried out to estimate the transmissivity of the global radiation (Ktβh) and the diffuse fraction (Kdβh) incident on a surface with slope of 22.85 ° in the hourly basis using machine learning techniques (MLT), from data obtained from 1998 to 2001 in Botucatu / SP / Brazil. The estimates were made using a series of combinations of astronomical and geographic variables by means of three artificial neural network (ANN) techniques such as MultLayer Perceptron (MLP), Radial Basis Functions Networks (RBF) and Generalized Regression Neural Network (GRNN) Adaptive Neuro Fuzzy Inference System (ANFIS). Statistical models (SM) of linear and polynomial regression were elaborated as reference. In Chapter 1 estimates of (Ktβh) were performed by combinations of variables measured and calculated from global horizontal surface irradiation (HgH) and estimates of (Kdβh) combinations of variables measured and calculated from (HgH) and global radiation on the sloped surface (Hgβ). In Chapter 2 estimates of (Kdβh) were performed by combinations of variables measured and calculated from the diffuse (HdH) and global (HgH) irradiances obtained on the horizontal surface. The statistical indicators r (correlation), RMSE (%) (precision) and MBE (%) (accuracy) were used to evaluate the results of the estimates. In Chapter 1 the best results in the estimates of (Ktβh) from the combinations performed with (HgH) were: MLP - RMSE = 3.73%; RBF - RMSE = 3.99%; GRNN - RMSE = 5.27%; A... (Complete abstract click electronic access below) / Doutor
237

Modelagem da esteira e otimização do posicionamento de aerogeradores em parques eólicos

Nowaczyk, Eduardo Ribas January 2015 (has links)
A otimização de processos tem como objetivo a maximização, ou minimização, de uma função objetivo que descreve o problema a ser resolvido. Para tanto, dependendo do problema e visando a obtenção da melhor resposta no menor tempo, podem ser utilizadas técnicas estocásticas ou determinísticas. Atualmente, o emprego de otimizadores não mais se restringe às aplicações da indústria de processos e manufaturas, mas também em outras áreas, como, por exemplo, a de energias renováveis. Esse fato se deve à conscientização acerca das consequências da utilização combustíveis fósseis e da busca pelo maior custo-benefício em projetos da área. Este trabalho tem como objetivo estudas o posicionamento de aerogeradores em um parque eólico utilizando otimização de processos. Para tal, foi desenvolvido um modelo baseado em Katic et al. (1986) para a descrição do déficit de velocidade do vento, aplicando o conceito de blending functions para combinar as perdas pelo efeito de esteira em todas as direções de vento incidente. O resultado é um modelo de rápida execução e qualitativamente correto. Comparou-se, então, soluções de otimizadores de busca direta global do tipo estocástico (PSO) e determinístico (DIRECT), escolhidos em função da não-regularidade da função objetivo. Considerou-se, também, o valor de 15% de perda de energia em relação à geração ideal como sendo o máximo aceitável para as respostas. O DIRECT alcançou soluções viáveis para até 8 turbinas, enquanto o PSO solucionou o problema para até 13 aerogeradores. Os resultados do PSO com 80 partículas e 100 iterações, para posicionamento de 13 aerogeradores, foi comparado com os resultados mostrados por Mosetti et al. (1994), mostrando uma necessidade de área de terreno cerca de cinco vezes menor para cada turbina. Avaliou-se, então, a influência os parâmetros algoritmo PSO, tanto os internos quantos os externos (número de partículas e iterações), em cenários de média e alta complexibilidade para a mesma quantidade de avaliações da função objetivo, respectivamente. As soluções encontradas mostraram que tais parâmetros tem grande efeito nas respostas dos otimizadores. / The aim of process optimization is maximize, or minimize, an objective function that describes a problem to be solved. To do that, depending on the problem and aiming the best solution in a shortest time, stochastic or deterministic techniques can be used. Currently, the use of optimizers no longer is restricted to process and manufacturing industrial problems, but in many others fields, like, for example, the renewable energy. This is due to the awareness about the consequences of using fossils fuels and looking for the best cost-effective in the projects of this area. The objective of this work is study the set of wind turbines in a wind park using process optimization. To do that, it was developed a model based on Katic et al. (1986) to describe the wind speed decay, using the knowledge of blending functions to add the wake losses in all wind directions. The result is a fast performance and qualitatively correct model. Then, global direct search optimizers solutions, a stochastic (PSO) and a deterministic (DIRECT), were compared. Those were chosen due the non-regular objective function. It was considerer 15% as the maximum acceptable energy losses, compared to the ideal, of the positioning answeres. The DIRECT reached viable solutions up to 8 turbines while the PSO solved the problem up to 13 turbines. The results of the PSO with 80 particles and 100 iteractions to positioning 13 turbines, was compared with the results shown by Mosetti et al. (1994) resulting in about 5 times less land required to each turbine. Then, it was evaluated the effect os the PSO parameters, inner and outer (number of particles and iteractions), in medium and high complexity scenarios to the same amount of objective functions evaluations. The solutions reached shown that those parameters have large influence in the optimizers solutions.
238

Realizace výpočetních úloh na MetaCentru / Realization of demanding computing tasks on MetaCentrum

HORELICA, Josef January 2013 (has links)
This thesis deals with the realization of demanding computing tasks on MetaCentrum. For these purposes was created the manual, which should help beginners on MetaCentrum. The first part is about the basic knowledge about parallel computation, characterization of means for computing, project MetaCentrum and some applications offered by MetaCentrum. In the second part there are the practical examples of computing on MetaCentrum. The enclosed CD contains the multimedia tutorial.
239

Desenvolvimento de sistema computacional via MATLAB/GUI (Graphical User Interface) para análise geometricamente não linear de estruturas.

Santana, Murillo Vinícius Bento January 2015 (has links)
Programa de Pós Graduação em Engenharia Civil. Departamento de Engenharia Civil, Escola de Minas, Universidade Federal de Ouro Preto. / Submitted by Oliveira Flávia (flavia@sisbin.ufop.br) on 2015-05-20T20:14:24Z No. of bitstreams: 2 license_rdf: 22190 bytes, checksum: 19e8a2b57ef43c09f4d7071d2153c97d (MD5) DISSERTAÇÃO_SistemaComputacionalGráfico.pdf: 7158699 bytes, checksum: 95038dc4d47ce770d2d418b6065f18d5 (MD5) / Approved for entry into archive by Gracilene Carvalho (gracilene@sisbin.ufop.br) on 2015-05-22T14:56:03Z (GMT) No. of bitstreams: 2 license_rdf: 22190 bytes, checksum: 19e8a2b57ef43c09f4d7071d2153c97d (MD5) DISSERTAÇÃO_SistemaComputacionalGráfico.pdf: 7158699 bytes, checksum: 95038dc4d47ce770d2d418b6065f18d5 (MD5) / Made available in DSpace on 2015-05-22T14:56:03Z (GMT). No. of bitstreams: 2 license_rdf: 22190 bytes, checksum: 19e8a2b57ef43c09f4d7071d2153c97d (MD5) DISSERTAÇÃO_SistemaComputacionalGráfico.pdf: 7158699 bytes, checksum: 95038dc4d47ce770d2d418b6065f18d5 (MD5) Previous issue date: 2015 / Com os avanços científicos e tecnológicos, o engenheiro estrutural passou a desenvolver e/ou ter acesso a programas computacionais que possibilitam análises numéricas mais avançadas. Isso vem proporcionando aumento da segurança e economia dos projetos. Para a concepção de estruturas mais esbeltas, a realização de análises não lineares geométricas, em que os efeitos de segunda ordem são explicitamente incluídos, torna-se cada vez mais comum. Nesse contexto, esta dissertação tem como objetivo avaliar o comportamento não linear geométrico estático de sistemas estruturais reticulados planos através do desenvolvimento e emprego de um sistema computacional gráfico interativo, denominado aqui AFA-OPSM (Advanced Frame Analysis - Ouro Preto School of Mines). Esse sistema utiliza os recursos de programação gráficos interativos (GUI) do software MATLAB, e apresenta, de forma acoplada, as etapas de pré-processamento, análise estrutural e pósprocessamento. Destaca-se ainda que ele é construído segundo o paradigma da programação orientada à objetos (POO), em que várias estratégias de solução não linear foram incorporadas. As formulações não lineares de elementos finitos são desenvolvidas considerando as teorias de treliças, de viga de Euler-Bernoulli e de Timoshenko, nos referenciais Lagrangiano total e co-rotacional. Os resultados numéricos obtidos, assim como os recursos gráficos interativos do AFA-OPSM, são avaliados através do estudo de problemas estruturais clássicos de estabilidade encontrados na literatura, alguns considerados fortemente não lineares. ______________________________________________________________________________ / ABSTRACT: With the scientific and technologic advances, the structural engineer has now access to computational programs that make possible more advanced numerical analysis. This have proportionate an increase in the safety and economy of projects. For the conception of slender structures, the use of geometrically nonlinear analysis, where second order effects are explicitly included, are becoming more and more common. In this context, this dissertation aims to evaluate the geometrically nonlinear static behavior of plane trusses and frame structural systems through the development and use of an interactive graphical computational system, named here AFA-OPSM (Advanced Frame Analysis – Ouro Preto School of Mines). This system is developed with the programming and graphics resources of the software MATLAB, and shows, in an integrated way, the phases of modeling, analysis and results visualization. Still, it is important to point out that this computational system is build following the object orientation paradigm, in which a diversity of nonlinear solution strategies are incorporated. The nonlinear finite elements formulations are developed considering the bar and the Euler-Bernoulli and Timoshenko beam theories, and the total Lagrangian and co-rotational reference systems. The numerical results obtained in this work, as well as the graphical resources in AFA-OPSM, are evaluated and validated through the study of classical stability structural problems found in literature, some of which are considered highly nonlinear.
240

Development of methods for modelling, parameter and state estimation for nonlinear processes

Dube, Ntuthuko Marcus January 2017 (has links)
Thesis (DTech (Electrical Engineering))--Cape Peninsula University of Technology, 2018. / Industrial processes tend to have very complex mathematical models that in most instances result in very model specific optimal estimation and designs of control strategies. Such models have many composition components, energy compartments and energy inventories that result in many process variables that are intertwined and too complex to separate from one another. Most of the derived mathematical process models, based on the application of first principles, are nonlinear and incorporate unknown parameters and unmeasurable states. This fact results in difficulties in design and implementation of controllers for a majority of industrial processes. There is a need for the existing parameter and state estimation methods to be further developed and for new methods to be developed in order to simplify the process of parameters or states calculation and be applicable for real-time implementation of various controllers for nonlinear systems. The thesis describes the research work done on developing new parameter and state estimation methods and algorithms for bilinear and nonlinear processes. Continuous countercurrent ion exchange (CCIX) process for desalination of water is considered as a case study of a process that can be modelled as a bilinear system with affine parameters or as purely nonlinear system. Many models of industrial processes can be presented in such a way. The ion exchange process model is developed based on the mass balance principle as a state space bilinear model according to the state and control variables. The developed model is restructured according to its parameters in order to formulate two types of parameter estimation problem – with process models linear and nonlinear according to the parameters. The two models developed are a bilinear model with affine and a nonlinear according to the parameters model. Four different methods are proposed for the first case: gradient-based optimization method that uses the process output measurements, optimization gradient based method that uses the full state vector measurements, direct solution using the state vector measurements, and Lagrange’s optimization technique. Two methods are proposed for the second case: direct solution of the model equation using MATLAB software and Lagrange’s optimisation techniques. / National Research Foundation (NRF)

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