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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.
61

An?lise e desenvolvimento de controladores preditivos multivari?veis baseados em multi-modelos bilineares / An?lise e desenvolvimento de controladores preditivos multivari?veis baseados em multi-modelos bilineares

Cavalcanti, Anderson Luiz de Oliveira 17 October 2008 (has links)
Made available in DSpace on 2014-12-17T14:54:50Z (GMT). No. of bitstreams: 1 AndersonLOC.pdf: 927541 bytes, checksum: 73019c94d2a3901e38fc25a788ef32fd (MD5) Previous issue date: 2008-10-17 / This work addresses issues related to analysis and development of multivariable predictive controllers based on bilinear multi-models. Linear Generalized Predictive Control (GPC) monovariable and multivariable is shown, and highlighted its properties, key features and applications in industry. Bilinear GPC, the basis for the development of this thesis, is presented by the time-step quasilinearization approach. Some results are presented using this controller in order to show its best performance when compared to linear GPC, since the bilinear models represent better the dynamics of certain processes. Time-step quasilinearization, due to the fact that it is an approximation, causes a prediction error, which limits the performance of this controller when prediction horizon increases. Due to its prediction error, Bilinear GPC with iterative compensation is shown in order to minimize this error, seeking a better performance than the classic Bilinear GPC. Results of iterative compensation algorithm are shown. The use of multi-model is discussed in this thesis, in order to correct the deficiency of controllers based on single model, when they are applied in cases with large operation ranges. Methods of measuring the distance between models, also called metrics, are the main contribution of this thesis. Several application results in simulated distillation columns, which are close enough to actual behaviour of them, are made, and the results have shown satisfactory / Este trabalho aborda aspectos relacionados ? an?lise e ao desenvolvimento de controladores preditivos multivari?veis baseados em multi-modelos bilineares. O Controlador Preditivo Generalizado (GPC) Monovari?vel e Multivari?vel para o caso linear ? apresentado, sendo destacadas suas propriedades, caracter?sticas principais e aplica??es na ind?stria. O GPC bilinear, que ? o controlador base de todo o desenvolvimento desta Tese, ? apresentado atrav?s da abordagem da quasilineariza??o por degrau de tempo. Alguns resultados empregando este controlador s?o apresentados de forma a evidenciar o melhor desempenho do mesmo, quando comparado ao GPC linear, visto que os modelos bilineares representam melhor a din?mica de determinados processos. A quasilineariza??o por degrau de tempo, devido ao fato de ser uma aproxima??o, provoca um erro de predi??o, que limita o desempenho deste controlador ? medida que seu horizonte de predi??o aumenta. Devido ao referido erro de predi??o, o GPC bilinear com compensa??o iterativa ? mostrado de forma a minimizar o referido erro, buscando um melhor desempenho que o GPC bilinear cl?ssico. Alguns resultados utilizando o algoritmo de compensa??o iterativa s?o mostrados. O emprego dos multi-modelos ? abordado nesta Tese, buscando suprir a defici?ncia existente em controladores baseados em modelo ?nico, quando os mesmos s?o aplicados em processos com grandes faixas de opera??o. Formas de mensura??o de dist?ncia entre modelos, tamb?m chamadas de m?tricas, consistem na principal contribui??o desta Tese. Diversos resultados de aplica??o em colunas de destila??o simuladas, que se aproximam bastante do comportamento real das mesmas, foram realizados, e os resultados se mostraram satisfat?rios
62

Controle preditivo bilinear aplicado a um motor de indu??o / Bilinear Predictive Controllers applied in an induction motor drive

Barros Filho, Adjair Ferreira 13 December 2002 (has links)
Made available in DSpace on 2014-12-17T14:55:34Z (GMT). No. of bitstreams: 1 AdjairFBF.pdf: 1621773 bytes, checksum: a2e7e0048de8c81be0d8971f8c7dd9bf (MD5) Previous issue date: 2002-12-13 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The present work is based on the applied bilinear predictive control applied to an induction motor. As in particular case of the technique based on predictive control in nonlinem systems, these have desperted great interest, a time that present the advantage of being simpler than the non linear in general and most representative one than the linear one. One of the methods, adopted here, uses the linear model "quasi linear for step of time" based in Generalized Predictive Control. The modeling of the induction motor is made by the Vectorial control with orientation given for the indirect rotor. The system is formed by an induction motor of 3 cv with rotor in squirregate, set in motion for a group of benches of tests developed for this work, presented resulted for a variation of +5% in the value of set-point and for a variation of +10% and -10% in the value of the applied nominal load to the motor. The results prove a good efficiency of the predictive bilinear controllers, then compared with the linear cases / O presente trabalho baseia-se na aplica??o da t?cnica de controle preditivo bilinear em um motor de indu??o. O controle preditivo bilinear, caso particular do controle preditivo n?o linear, t?m despertado grande interesse, uma vez que apresenta a vantagem de ser mais simples que o n?o linear em geral e mais representativo que o linear. Um dos m?todos, aqui adotado, utiliza o modelo "quase linear por degrau de tempo" baseado no Controlador Preditivo Generalizado. A modelagem do motor de indu??o ? feita atrav?s do controle Vetorial com orienta??o dada pelo campo do rotor indireto. O sistema ? formado por um motor de indu??o de 3 HP como rotor em gaiola de esquilo, acionado por uma bancada de testes desenvolvida para esse trabalho. Foram obtidos resultados para uma vaira??o de +5% no valor do set-point e resultados para uma varia??o de +10% e -10% no valor da carga nominal aplicada ao motor. Os resultados comprovam uma boa efici?ncia dos controladores preditivos bilineares, quando comparados com os casos lineares
63

Contributions à la résolution globale de problèmes bilinéaires appliqués à l'indstrie porcine / Contribution to the global resolution of bilinear problems applied to the swine industry

Joannopoulos, Emilie 27 April 2018 (has links)
Aujourd'hui, l'alimentation représente plus de 70% du coût de production en engraissement porcin et dans le contexte économique actuel, il est important de parvenir à réduire ce coût. L'alimentation utilisée actuellement utilise des phases et est représentée par un modèle linéaire. L'alimentation par mélanges introduite récemment est représentée par un modèle bilinéaire. Nous introduisons ici une nouvelle formulation qui est une combinaison des alimentations traditionnelle par mélanges: la méthode hybride. Nous montrons qu'elle permet de réduire le coût de plus de 5%. L'étude principale porte sur l'optimisation globale du problème bilinéaire, non convexe, modélisant l'alimentation par mélanges. La bilinéarité apparaît dans la fonction objectif et dans les contraintes. Ce problème peut posséder plusieurs minima, mais nous souhaitons obtenir un minimum global. Il est équivalent à un problème de pooling et nous montrons qu'il est fortement NP-difficile. Après de premiers résultats, nous énonçons la conjecture que tout minimum local est global pour ce problème bilinéaire appliqué à l'industrie porcine. Nous la prouvons sur un exemple de dimension réduite. Notre problème ne pouvant pas être résolu avec des solveurs globaux à cause de sa dimension, nous utilisons des approches telle que la pénalisation, la discrétisation, et techniques de relaxation lagrangienne ou convexe. Toutes ces approches supportent notre conjecture. Nous faisons également une étude de la robustesse des modèles à la variation des prix des ingrédients ainsi qu'une étude multicritère nous permettant d'obtenir des résultats numériques réduisant considérablement les rejets, autres enjeux importants. / Today, feed represents more than 70% of the production cost in growing-finishing pig industry and in the current economic context, it is important to reduce it. The feeding system currently used uses phases and is expressed as a linear model. The feeding system using feeds introduced more recently is represented by a bilinear model. We introduced here new feeding system which is a combination offeeding systems using phases and feeds: the hybrid method. We show that it can reduce the feed cost by more than 5%. The main part of this manuscript is about global optimization of the bilinear problem, and non convex, problem modeling feeding system using feeds. The objective function and some constraints are bilinear. This problem can have several local minima but we would like to have a global one. It is equivalent to a pooling problem and we prove that it is a strongly NP-hard problem. After a study of first results, we enounce the conjecture that any local minimum is a global minimum for that problem applied in the pig industry. We prove it for a small size example. Our problem cannot be solved by using global solver due to its size, then we applied some relaxation methods such as penalization of bilinear terms, their discretization and Langrangian and convex relaxations. All these approaches support our conjecture. Then we study the robustness of the models on the ingredient price variations and a multicriteria study reducing phosphorus and nitrogen excretion.
64

Speciální přístupy k modelování nelineárních časových řad / Special aspects of non-linear time series modelling

Studnička, Václav January 2018 (has links)
Various models, such as ARMA and GARCH, are used in the financial time series framework. The purpose of this thesis is to present an alternative for these models which are bilinear time series models. First chapter is theore- tical, there is a short introduction to the theory of time series and ARMA models. Second chapter focuses on theoretical aspects of the simple bilinear model, third chapter presents the theory for general bilinear model in the similiar fashion as for simple model. Last chapter is focused on practical aspects, it contains simulations and examines the properties of estimates based on the presented theory, final part is devoted to the comparison of properties of ARMA models and bilinear models for selected financial data. 1
65

Cifrassinatura sem certificados em curvas supersingulares sobre corpos binarios / Certificateless signcryption on supersingular elliptic curves over bilinear fields

Morais, Eduardo Moraes de, 1983- 14 August 2018 (has links)
Orientador: Ricardo Dahab / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Computação / Made available in DSpace on 2018-08-14T04:06:33Z (GMT). No. of bitstreams: 1 Morais_EduardoMoraesde_M.pdf: 1060073 bytes, checksum: 349e64f9f2a5456f3af935607dfa5e3d (MD5) Previous issue date: 2009 / Resumo: A criptografia baseada em identidades representa uma alternativa ao modelo de certificação digital, exigindo menor esforço para solucionar o problema de autenticidade da chave pública, mas perdendo a custódia da chave privada, que será gerada por uma autoridade de confiança. O modelo de criptografia sem certificados soluciona o problema da custódia da chave privada sem a utilização de certificados digitais. Neste modelo, o usuário tem a posse de uma parte da chave privada e com isso a chave pública passa a ser constituída de uma parte gerada pela autoridade de confiança e uma parte gerada pelo usuário. A cifrassinatura é uma primitiva criptográfica que reúne as vantagens do ciframento e da assinatura em uma única operação, permitindo maior eficiência e segurança. A literatura possui diversas propostas de ciframento sem certificados e assinatura sem certificados, mas não tem uma proposta genérica de cifrassinatura sem certificados. Este trabalho propõe um protocolo de cifrassinatura sem certificados eficiente, que pode ser implementado usando dois emparelhamentos bilineares. Considerando a importância de emparelhamentos bilineares para a construção do protocolo proposto, este trabalho apresenta os conceitos matemáticos necessários para a obtenção de emparelhamentos bilineares eficientes e resistentes a ataques ao problema do logaritmo discreto sobre a curva elíptica e sobre o corpo de extensão resultante do cálculo do emparelhamento bilinear. São apresentados também algoritmos eficientes para aritmética de precisão arbitrária, aritmética de curvas elípticas e cálculo de emparelhamentos. Além disso, são discutidos modelos formais de segurança, como por exemplo o modelo do oráculo aleatório. Finalmente, o modelo de criptografia baseada em identidades e o modelo de criptografia sem certificados são discutidos e com isso é possível apresentar a proposta de cifrassinatura sem certificados e argumentar que esta proposta _e segura e eficiente / Abstract: Identity based cryptography is an alternative to digital certification, which requires less computational effort to solve the problem of public key authenticity. On the other hand, identity based cryptography has the problem of key escrow, because the private key is generated by a trust authority. The certificateless cryptography model solves the key escrow problem without digital certificates. In this model, the user computes a parcial private key that is used to compose the entire private key. In the same way, the public key has two parts: one generated by the user and the other generated by the trust authority. Signcryption is a cryptographic primitive that has the advantages of encryption and signature together in a single operation, allowing the construction of secure and efficient protocols. The literature has many certificateless encryption and certificateless signature protocols, but there is no generic and efficient certificateless signcryption scheme. This work proposes an efficient certificateless signcryption protocol, that can be implemented with just two bilinear pairings. Considering the importance of bilinear pairings for the construction of the proposed protocol, this work presents the mathematical concepts for efficient bilinear pairings, that can resist against discrete logarithm atacks on the elliptic curve and on the extension field. This works also presents efficient algorithms for big number arithmetic, elliptic curve arithmetic and the Miller algorithm for pairings. It also presents formal security models, such as the random oracle model. Finally, identity based cryptography and certificateless cryptography models are defined and the proposed certificateless signcryption scheme is presented and we argue that it is secure and eficient, although no formal proof is given / Mestrado / Criptografia / Mestre em Ciência da Computação
66

Software implementation of cryptography for wireless sensors and mobile processors = Implementação em software de criptografia para sensores sem fio e processadores móveis / Implementação em software de criptografia para sensores sem fio e processadores móveis

Gouvêa, Conrado Porto Lopes, 1984- 11 August 2013 (has links)
Orientador: Julio César López Hernández / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Computação / Made available in DSpace on 2018-08-24T00:18:34Z (GMT). No. of bitstreams: 1 Gouvea_ConradoPortoLopes_D.pdf: 3342900 bytes, checksum: b3a072bdbc369f1a1fffd95e1c1f4365 (MD5) Previous issue date: 2013 / Resumo: A implementação eficiente e segura de esquemas criptográficos é um aspecto importante da criptografia aplicada. Neste trabalho, foca-se na implementação em software de algoritmos relevantes da criptografia de curvas elípticas (CCE), criptografia baseada em emparelhamentos (CBE), e de cifração autenticada (CA). Duas plataformas computacionais modernas foram utilizadas: o microcontrolador MSP430, bastante utilizado em redes de sensores sem fio, e o processador ARM, amplamente empregado por dispositivos móveis como smartphones e tablets que estão se tornando cada vez mais populares. Técnicas para a melhoria de desempenho em software utilizando conjuntos de instruções, periféricos e melhorias algorítmicas são descritas. A implementação segura, cujo objetivo é prevenir certos ataques de canais secundários, também é estudada e novas técnicas são providas para reduzir seu impacto na velocidade em processadores ARM. Tais resultados contribuem para a construção eficiente e segura de sistemas criptográficos em sensores sem fio e processadores móveis / Abstract: The efficient and secure implementation of cryptographic schemes is an important aspect of practical cryptography. In this work, we focus on the software implementation of relevant algorithms in elliptic curve cryptography (ECC), pairing-based cryptography (PBC) and in authenticated encryption (AE). Two modern computational platforms were targeted: the MSP430 microcontroller often used in wireless sensor networks, and the ARM processor, widely employed in mobile devices such as smartphones and tablets which are increasingly becoming ubiquitous. Techniques for improving the software performance by taking advantage of instruction sets, peripherals and algorithmic enhancements are described. The secure implementation, which aims at thwarting common side-channel attacks, is also studied and new techniques are provided for improving its efficiency on ARM processors. These results contribute to the building of efficient and secure cryptographic systems on wireless sensors and mobile processors / Doutorado / Ciência da Computação / Doutor em Ciência da Computação
67

Resonant Solutions to (3+1)-dimensional Bilinear Differential Equations

Sun, Yue 23 March 2016 (has links)
In this thesis, we attempt to obtain a class of generalized bilinear differential equations in (3+1)-dimensions by Dp-operators with p = 5, which have resonant solutions. We construct resonant solutions by using the linear superposition principle and parameterizations of wave numbers and frequencies. We test different values of p in Maple computations, and generate three classes of generalized bilinear differential equations and their resonant solutions when p = 5.
68

Lump, complexiton and algebro-geometric solutions to soliton equations

Zhou, Yuan 28 June 2017 (has links)
In chapter 2, we study two Kaup-Newell-type matrix spectral problems, derive their soliton hierarchies within the zero curvature formulation, and furnish their bi-Hamiltonian structures by the trace identity to show that they are integrable in the Liouville sense. In chapter 5, we obtain the Riemann theta function representation of solutions for the first hierarchy of generalized Kaup-Newell systems. In chapter 3, using Hirota bilinear forms, we discuss positive quadratic polynomial solutions to generalized bilinear equations, which generate lump or lump-type solutions to nonlinear evolution equations, and propose an algorithm for computing higher-order lump or lump-type solutions. In chapter 4, we study mixed exponential and trigonometric wave solutions (called complexitons) to general bilinear equations, and propose two methods to find complexitons to generalized bilinear equations. We also succeed in proving that by choosing suitable complex coefficients in soliton solutions, multi-complexitons are actually real wave solutions from complex soliton solutions and establish the linear superposition principle for complexion solutions. In each chapter, we present computational examples.
69

Efektivní schémata digitálních podpisů / Efficient Digital Signature Schemes

Varga, Ondrej January 2011 (has links)
Digital signatures, which take the properties of classical signatures, are used to secure the actual content of documents, which can be modified during transmission over an insecure channel. The problems of security and protection of communicating participants are solved by cryptographic techniques. Identity verification, message integrity, credibility, the ownership of documents, and the secure transmission of information over an unsecured channel, are all dealt with in secure communications - Public Key Infrastructure, which uses digital signatures. Nowadays digital signatures are often used to secure data in communication over an unsecured channel. The aim of the following master’s thesis is to familiarize readers with the necessary technological aspects of digital signatures, as well as their advantages and disadvantages. By the time digital signatures are being used they will have to be improved and modified to be secure against more sophisticated attacks. In this paper, proposals of new efficient digital signature schemes and their comparison with current ones are described. Also are examined their implications for computationally weak devices, or deployment in low speed channel transmission systems. After an explanation of cryptography and a description of its basic subjects, digital signatures are introduced. The first chapter describes the possible formatting and architecture of the digital signature. The second part of this master’s thesis is about current digital signature schemes and their properties. Chapter 3 describes some proposals of new efficient digital signature schemes and their comparison to those currently in use. In the practical part, the implementations (in the environment .NET in C#) of two effective digital signature schemes as part of a client-server application are presented and described (Chapter 4). In the last chapter the comparison and analysis of the implemented signature schemes are provided.
70

ADVANCES ON BILINEAR MODELING OF BIOCHEMICAL BATCH PROCESSES

González Martínez, José María 07 October 2015 (has links)
[EN] This thesis is aimed to study the implications of the statistical modeling approaches proposed for the bilinear modeling of batch processes, develop new techniques to overcome some of the problems that have not been yet solved and apply them to data of biochemical processes. The study, discussion and development of the new methods revolve around the four steps of the modeling cycle, from the alignment, preprocessing and calibration of batch data to the monitoring of batches trajectories. Special attention is given to the problem of the batch synchronization, and its effect on the modeling from different angles. The manuscript has been divided into four blocks. First, a state-of- the-art of the latent structures based-models in continuous and batch processes and traditional univariate and multivariate statistical process control systems is carried out. The second block of the thesis is devoted to the preprocessing of batch data, in particular, to the equalization and synchronization of batch trajectories. The first section addresses the problem of the lack of equalization in the variable trajectories. The different types of unequalization scenarios that practitioners might finnd in batch processes are discussed and the solutions to equalize batch data are introduced. In the second section, a theoretical study of the nature of batch processes and of the synchronization of batch trajectories as a prior step to bilinear modeling is carried out. The topics under discussion are i) whether the same synchronization approach must be applied to batch data in presence of different types of asynchronisms, and ii) whether synchronization is always required even though the length of the variable trajectories are constant across batches. To answer these questions, a thorough study of the most common types of asynchronisms that may be found in batch data is done. Furthermore, two new synchronization techniques are proposed to solve the current problems in post-batch and real-time synchronization. To improve fault detection and classification, new unsupervised control charts and supervised fault classifiers based on the information generated by the batch synchronization are also proposed. In the third block of the manuscript, a research work is performed on the parameter stability associated with the most used synchronization methods and principal component analysis (PCA)-based Batch Multivariate Statistical Process Control methods. The results of this study have revealed that accuracy in batch synchronization has a profound impact on the PCA model parameters stability. Also, the parameter stability is closely related to the type of preprocessing performed in batch data, and the type of model and unfolding used to transform the three-way data structure to two-way. The setting of the parameter stability, the source of variability remaining after preprocessing and the process dynamics should be balanced in such a way that multivariate statistical models are accurate in fault detection and diagnosis and/or in online prediction. Finally, the fourth block introduces a graphical user-friendly interface developed in Matlab code for batch process understanding and monitoring. To perform multivariate analysis, the last developments in process chemometrics, including the methods proposed in this thesis, are implemented. / [ES] La presente tesis doctoral tiene como objetivo estudiar las implicaciones de los métodos estadísticos propuestos para la modelización bilineal de procesos por lotes, el desarrollo de nuevas técnicas para solucionar algunos de los problemas más complejos aún por resolver en esta línea de investigación y aplicar los nuevos métodos a datos provenientes de procesos bioquímicos para su evaluación estadística. El estudio, la discusión y el desarrollo de los nuevos métodos giran en torno a las cuatro fases del ciclo de modelización: desde la sincronización, ecualización, preprocesamiento y calibración de los datos, a la monitorización de las trayectorias de las variables del proceso. Se presta especial atención al problema de la sincronización y su efecto en la modelización estadística desde distintas perspectivas. El manuscrito se ha dividido en cuatro grandes bloques. En primer lugar, se realiza una revisión bibliográfica de las técnicas de proyección sobre estructuras latentes para su aplicación en procesos continuos y por lotes, y del diseño de sistemas de control basados en modelos estadísticos multivariantes. El segundo bloque del documento versa sobre el preprocesamiento de los datos, en concreto, sobre la ecualización y la sincronización. La primera parte aborda el problema de la falta de ecualización en las trayectorias de las variables. Se discuten las diferentes políticas de muestreo que se pueden encontrar en procesos por lotes y las soluciones para ecualizar las variables. En la segunda parte de esta sección, se realiza un estudio teórico sobre la naturaleza de los procesos por lotes y de la sincronización de las trayectorias como paso previo a la modelización bilineal. Los temas bajo discusión son: i) si se debe utilizar el mismo enfoque de sincronización en lotes afectados por diferentes tipos de asincronismos, y ii) si la sincronización es siempre necesaria aún y cuando las trayectorias de las variables tienen la misma duración en todos los lotes. Para responder a estas preguntas, se lleva a cabo un estudio exhaustivo de los tipos más comunes de asincronismos que se pueden encontrar en este tipo de datos. Además, se proponen dos nuevas técnicas de sincronización para resolver los problemas existentes en aplicaciones post-morten y en tiempo real. Para mejorar la detección de fallos y la clasificación, también se proponen nuevos gráficos de control no supervisados y clasificadores de fallos supervisados en base a la información generada por la sincronización de los lotes. En el tercer bloque del manuscrito se realiza un estudio de la estabilidad de los parámetros asociados a los métodos de sincronización y a los métodos estadístico multivariante basados en el Análisis de Componentes Principales (PCA) más utilizados para el control de procesos. Los resultados de este estudio revelan que la precisión de la sincronización de las trayectorias tiene un impacto significativo en la estabilidad de los parámetros de los modelos PCA. Además, la estabilidad paramétrica está estrechamente relacionada con el tipo de preprocesamiento realizado en los datos de los lotes, el tipo de modelo a justado y el despliegue utilizado para transformar la estructura de datos de tres a dos dimensiones. El ajuste de la estabilidad de los parámetros, la fuente de variabilidad que queda después del preprocesamiento de los datos y la captura de las dinámicas del proceso deben ser a justados de forma equilibrada de tal manera que los modelos estadísticos multivariantes sean precisos en la detección y diagnóstico de fallos y/o en la predicción en tiempo real. Por último, el cuarto bloque del documento describe una interfaz gráfica de usuario que se ha desarrollado en código Matlab para la comprensión y la supervisión de procesos por lotes. Para llevar a cabo los análisis multivariantes, se han implementado los últimos desarrollos en la quimiometría de proc / [CA] Aquesta tesi doctoral te com a objectiu estudiar les implicacions dels mètodes de modelització estadística proposats per a la modelització bilineal de processos per lots, el desenvolupament de noves tècniques per resoldre els problemes encara no resolts en aquesta línia de recerca i aplicar els nous mètodes a les dades dels processos bioquímics. L'estudi, la discussió i el desenvolupament dels nous mètodes giren entorn a les quatre fases del cicle de modelització, des de l'alineació, preprocessament i el calibratge de les dades provinents de lots, a la monitorització de les trajectòries. Es presta especial atenció al problema de la sincronització per lots, i el seu efecte sobre el modelatge des de diferents angles. El manuscrit s'ha dividit en quatre grans blocs. En primer lloc, es realitza una revisió bibliogràfica dels principals mètodes basats en tècniques de projecció sobre estructures latents en processos continus i per lots, així com dels sistemes de control estadístics multivariats. El segon bloc del document es dedica a la preprocessament de les dades provinents de lots, en particular, l' equalització i la sincronització. La primera part aborda el problema de la manca d'equalització en les trajectòries de les variables. Es discuteixen els diferents tipus d'escenaris en que les variables estan mesurades a distints intervals i les solucions per equalitzar-les en processos per lots. A la segona part d'aquesta secció es porta a terme un estudi teòric de la naturalesa dels processos per lots i de la sincronització de les trajectòries de lots com a pas previ al modelatge bilineal. Els temes en discussió són: i) si el mateix enfocament de sincronització ha de ser aplicat a les dades del lot en presència de diferents tipus de asincronismes, i ii) si la sincronització sempre es requereix tot i que la longitud de les trajectòries de les variables són constants en tots el lots. Per respondre a aquestes preguntes, es du a terme un estudi exhaustiu dels tipus més comuns de asincronismes que es poden trobar en les dades provinents de lots. A més, es proposen dues noves tècniques de sincronització per resoldre els problemes existents la sincronització post-morten i en temps real. Per millorar la detecció i la classificació de anomalies, també es proposen nous gràfics de control no supervisats i classificadors de falla supervisats dissenyats en base a la informació generada per la sincronització de lots. En el tercer bloc del manuscrit es realitza un treball de recerca sobre l'estabilitat dels paràmetres associats als mètodes de sincronització i als mètodes estadístics multivariats basats en l'Anàlisi de Components Principals (PCA) més utilitzats per al control de processos. Els resultats d'aquest estudi revelen que la precisió en la sincronització per lots te un profund impacte en l'estabilitat dels paràmetres dels models PCA. A més, l'estabilitat paramètrica està estretament relacionat amb el tipus de preprocessament realitzat en les dades provinents de lots, el tipus de model i el desplegament utilitzat per transformar l'estructura de dades de tres a dos dimensions. L'ajust de l'estabilitat dels paràmetres, la font de variabilitat que queda després del preprocessament i la captura de la dinàmica de procés ha de ser equilibrada de tal manera que els models estadístics multivariats són precisos en la detecció i diagnòstic de fallades i/o en la predicció en línia. Finalment, el quart bloc del document introdueix una interfície gràfica d'usuari que s'ha dissenyat e implementat en Matlab per a la comprensió i la supervisió de processos per lots. Per dur a terme aquestes anàlisis multivariats, s'han implementat els últims desenvolupaments en la quimiometria de processos, incloent-hi els mètodes proposats en aquesta tesi. / González Martínez, JM. (2015). ADVANCES ON BILINEAR MODELING OF BIOCHEMICAL BATCH PROCESSES [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/55684 / TESIS / Premios Extraordinarios de tesis doctorales

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