856 resultados para Population set-based methods


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It is essential to remotely and continuously monitor the movements of individuals in many social areas, for example, taking care of aging people, physical therapy, athletic training etc. Many methods have been used, such as video record, motion analysis or sensor-based methods. Due to the limitations in remote communication, power consumption, portability and so on, most of them are not able to fulfill the requirements. The development of wearable technology and cloud computing provides a new efficient way to achieve this goal. This paper presents an intelligent human movement monitoring system based on a smartwatch, an Android smartphone and a distributed data management engine. This system includes advantages of wide adaptability, remote and long-term monitoring capacity, high portability and flexibility. The structure of the system and its principle are introduced. Four experiments are designed to prove the feasibility of the system. The results of the experiments demonstrate the system is able to detect different actions of individuals with adequate accuracy.

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habilidades de comprensión y resolución de problemas. Tanto es así que se puede afirmar con rotundidad que no existe el método perfecto para cada una de las etapas de desarrollo y tampoco existe el modelo de ciclo de vida perfecto: cada nuevo problema que se plantea es diferente a los anteriores en algún aspecto y esto hace que técnicas que funcionaron en proyectos anteriores fracasen en los proyectos nuevos. Por ello actualmente se realiza un planteamiento integrador que pretende utilizar en cada caso las técnicas, métodos y herramientas más acordes con las características del problema planteado al ingeniero. Bajo este punto de vista se plantean nuevos problemas. En primer lugar está la selección de enfoques de desarrollo. Si no existe el mejor enfoque, ¿cómo se hace para elegir el más adecuado de entre el conjunto de los existentes? Un segundo problema estriba en la relación entre las etapas de análisis y diseño. En este sentido existen dos grandes riesgos. Por un lado, se puede hacer un análisis del problema demasiado superficial, con lo que se produce una excesiva distancia entre el análisis y el diseño que muchas veces imposibilita el paso de uno a otro. Por otro lado, se puede optar por un análisis en términos del diseño que provoca que no cumpla su objetivo de centrarse en el problema, sino que se convierte en una primera versión de la solución, lo que se conoce como diseño preliminar. Como consecuencia de lo anterior surge el dilema del análisis, que puede plantearse como sigue: para cada problema planteado hay que elegir las técnicas más adecuadas, lo que requiere que se conozcan las características del problema. Para ello, a su vez, se debe analizar el problema, eligiendo una técnica antes de conocerlo. Si la técnica utiliza términos de diseño entonces se ha precondicionado el paradigma de solución y es posible que no sea el más adecuado para resolver el problema. En último lugar están las barreras pragmáticas que frenan la expansión del uso de métodos con base formal, dificultando su aplicación en la práctica cotidiana. Teniendo en cuenta todos los problemas planteados, se requieren métodos de análisis del problema que cumplan una serie de objetivos, el primero de los cuales es la necesidad de una base formal, con el fin de evitar la ambigüedad y permitir verificar la corrección de los modelos generados. Un segundo objetivo es la independencia de diseño: se deben utilizar términos que no tengan reflejo directo en el diseño, para que permitan centrarse en las características del problema. Además los métodos deben permitir analizar problemas de cualquier tipo: algorítmicos, de soporte a la decisión o basados en el conocimiento, entre otros. En siguiente lugar están los objetivos relacionados con aspectos pragmáticos. Por un lado deben incorporar una notación textual formal pero no matemática, de forma que se facilite su validación y comprensión por personas sin conocimientos matemáticos profundos pero al mismo tiempo sea lo suficientemente rigurosa para facilitar su verificación. Por otro lado, se requiere una notación gráfica complementaria para representar los modelos, de forma que puedan ser comprendidos y validados cómodamente por parte de los clientes y usuarios. Esta tesis doctoral presenta SETCM, un método de análisis que cumple estos objetivos. Para ello se han definido todos los elementos que forman los modelos de análisis usando una terminología independiente de paradigmas de diseño y se han formalizado dichas definiciones usando los elementos fundamentales de la teoría de conjuntos: elementos, conjuntos y relaciones entre conjuntos. Por otro lado se ha definido un lenguaje formal para representar los elementos de los modelos de análisis – evitando en lo posible el uso de notaciones matemáticas – complementado con una notación gráfica que permite representar de forma visual las partes más relevantes de los modelos. El método propuesto ha sido sometido a una intensa fase de experimentación, durante la que fue aplicado a 13 casos de estudio, todos ellos proyectos reales que han concluido en productos transferidos a entidades públicas o privadas. Durante la experimentación se ha evaluado la adecuación de SETCM para el análisis de problemas de distinto tamaño y en sistemas cuyo diseño final usaba paradigmas diferentes e incluso paradigmas mixtos. También se ha evaluado su uso por analistas con distinto nivel de experiencia – noveles, intermedios o expertos – analizando en todos los casos la curva de aprendizaje, con el fin de averiguar si es fácil de aprender su uso, independientemente de si se conoce o no alguna otra técnica de análisis. Por otro lado se ha estudiado la capacidad de ampliación de modelos generados con SETCM, para comprobar si permite abordar proyectos realizados en varias fases, en los que el análisis de una fase consista en ampliar el análisis de la fase anterior. En resumidas cuentas, se ha tratado de evaluar la capacidad de integración de SETCM en una organización como la técnica de análisis preferida para el desarrollo de software. Los resultados obtenidos tras esta experimentación han sido muy positivos, habiéndose alcanzado un alto grado de cumplimiento de todos los objetivos planteados al definir el método.---ABSTRACT---Software development is an inherently complex activity, which requires specific abilities of problem comprehension and solving. It is so difficult that it can even be said that there is no perfect method for each of the development stages and that there is no perfect life cycle model: each new problem is different to the precedent ones in some respect and the techniques that worked in other problems can fail in the new ones. Given that situation, the current trend is to integrate different methods, tools and techniques, using the best suited for each situation. This trend, however, raises some new problems. The first one is the selection of development approaches. If there is no a manifestly single best approach, how does one go about choosing an approach from the array of available options? The second problem has to do with the relationship between the analysis and design phases. This relation can lead to two major risks. On one hand, the analysis could be too shallow and far away from the design, making it very difficult to perform the transition between them. On the other hand, the analysis could be expressed using design terminology, thus becoming more a kind of preliminary design than a model of the problem to be solved. In third place there is the analysis dilemma, which can be expressed as follows. The developer has to choose the most adequate techniques for each problem, and to make this decision it is necessary to know the most relevant properties of the problem. This implies that the developer has to analyse the problem, choosing an analysis method before really knowing the problem. If the chosen technique uses design terminology then the solution paradigm has been preconditioned and it is possible that, once the problem is well known, that paradigm wouldn’t be the chosen one. The last problem consists of some pragmatic barriers that limit the applicability of formal based methods, making it difficult to use them in current practice. In order to solve these problems there is a need for analysis methods that fulfil several goals. The first one is the need of a formal base, which prevents ambiguity and allows the verification of the analysis models. The second goal is design-independence: the analysis should use a terminology different from the design, to facilitate a real comprehension of the problem under study. In third place the analysis method should allow the developer to study different kinds of problems: algorithmic, decision-support, knowledge based, etc. Next there are two goals related to pragmatic aspects. Firstly, the methods should have a non mathematical but formal textual notation. This notation will allow people without deep mathematical knowledge to understand and validate the resulting models, without losing the needed rigour for verification. Secondly, the methods should have a complementary graphical notation to make more natural the understanding and validation of the relevant parts of the analysis. This Thesis proposes such a method, called SETCM. The elements conforming the analysis models have been defined using a terminology that is independent from design paradigms. Those terms have been then formalised using the main concepts of the set theory: elements, sets and correspondences between sets. In addition, a formal language has been created, which avoids the use of mathematical notations. Finally, a graphical notation has been defined, which can visually represent the most relevant elements of the models. The proposed method has been thoroughly tested during the experimentation phase. It has been used to perform the analysis of 13 actual projects, all of them resulting in transferred products. This experimentation allowed evaluating the adequacy of SETCM for the analysis of problems of varying size, whose final design used different paradigms and even mixed ones. The use of the method by people with different levels of expertise was also evaluated, along with the corresponding learning curve, in order to assess if the method is easy to learn, independently of previous knowledge on other analysis techniques. In addition, the expandability of the analysis models was evaluated, assessing if the technique was adequate for projects organised in incremental steps, in which the analysis of one step grows from the precedent models. The final goal was to assess if SETCM can be used inside an organisation as the preferred analysis method for software development. The obtained results have been very positive, as SETCM has obtained a high degree of fulfilment of the goals stated for the method.

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Fluid flow and fabric compaction during vacuum assisted resin infusion (VARI) of composite materials was simulated using a level set-based approach. Fluid infusion through the fiber preform was modeled using Darcy’s equations for the fluid flow through a porous media. The stress partition between the fluid and the fiber bed was included by means of Terzaghi’s effective stress theory. Tracking the fluid front during infusion was introduced by means of the level set method. The resulting partial differential equations for the fluid infusion and the evolution of flow front were discretized and solved approximately using the finite differences method with a uniform grid discretization of the spatial domain. The model results were validated against uniaxial VARI experiments through an [0]8 E-glass plain woven preform. The physical parameters of the model were also independently measured. The model results (in terms of the fabric thickness, pressure and fluid front evolution during filling) were in good agreement with the numerical simulations, showing the potential of the level set method to simulate resin infusion

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The operating theatres are the engine of the hospitals; proper management of the operating rooms and its staff represents a great challenge for managers and its results impact directly in the budget of the hospital. This work presents a MILP model for the efficient schedule of multiple surgeries in Operating Rooms (ORs) during a working day. This model considers multiple surgeons and ORs and different types of surgeries. Stochastic strategies are also implemented for taking into account the uncertain in surgery durations (pre-incision, incision, post-incision times). In addition, a heuristic-based methods and a MILP decomposition approach is proposed for solving large-scale ORs scheduling problems in computational efficient way. All these computer-aided strategies has been implemented in AIMMS, as an advanced modeling and optimization software, developing a user friendly solution tool for the operating room management under uncertainty.

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La motivación de esta tesis es el desarrollo de una herramienta de optimización automática para la mejora del rendimiento de formas aerodinámicas enfocado en la industria aeronáutica. Este trabajo cubre varios aspectos esenciales, desde el empleo de Non-Uniform Rational B-Splines (NURBS), al cálculo de gradientes utilizando la metodología del adjunto continuo, el uso de b-splines volumétricas como parámetros de diseño, el tratamiento de la malla en las intersecciones, y no menos importante, la adaptación de los algoritmos de la dinámica de fluidos computacional (CFD) en arquitecturas hardware de alto paralelismo, como las tarjetas gráficas, para acelerar el proceso de optimización. La metodología adjunta ha posibilitado que los métodos de optimización basados en gradientes sean una alternativa prometedora para la mejora de la eficiencia aerodinámica de los aviones. La formulación del adjunto permite calcular los gradientes de una función de coste, como la resistencia aerodinámica o la sustentación, independientemente del número de variables de diseño, a un coste computacional equivalente a una simulación CFD. Sin embargo, existen problemas prácticos que han imposibilitado su aplicación en la industria, que se pueden resumir en: integrabilidad, rendimiento computacional y robustez de la solución adjunta. Este trabajo aborda estas contrariedades y las analiza en casos prácticos. Como resumen, las contribuciones de esta tesis son: • El uso de NURBS como variables de diseño en un bucle de automático de optimización, aplicado a la mejora del rendimiento aerodinámico de alas en régimen transónico. • El desarrollo de algoritmos de inversión de punto, para calcular las coordenadas paramétricas de las coordenadas espaciales, para ligar los vértices de malla a las NURBS. • El uso y validación de la formulación adjunta para el calculo de los gradientes, a partir de las sensibilidades de la solución adjunta, comparado con diferencias finitas. • Se ofrece una estrategia para utilizar la geometría CAD, en forma de parches NURBS, para tratar las intersecciones, como el ala-fuselaje. • No existen muchas alternativas de librerías NURBS viables. En este trabajo se ha desarrollado una librería, DOMINO NURBS, y se ofrece a la comunidad como código libre y abierto. • También se ha implementado un código CFD en tarjeta gráfica, para realizar una valoración de cómo se puede adaptar un código sobre malla no estructurada a arquitecturas paralelas. • Finalmente, se propone una metodología, basada en la función de Green, como una forma eficiente de paralelizar simulaciones numéricas. Esta tesis ha sido apoyada por las actividades realizadas por el Área de Dinámica da Fluidos del Instituto Nacional de Técnica Aeroespacial (INTA), a través de numerosos proyectos de financiación nacional: DOMINO, SIMUMAT, y CORESFMULAERO. También ha estado en consonancia con las actividades realizadas por el departamento de Métodos y Herramientas de Airbus España y con el grupo Investigación y Tecnología Aeronáutica Europeo (GARTEUR), AG/52. ABSTRACT The motivation of this work is the development of an automatic optimization strategy for large scale shape optimization problems that arise in the aeronautics industry to improve the aerodynamic performance; covering several aspects from the use of Non-Uniform Rational B-Splines (NURBS), the calculation of the gradients with the continuous adjoint formulation, the development of volumetric b-splines parameterization, mesh adaptation and intersection handling, to the adaptation of Computational Fluid Dynamics (CFD) algorithms to take advantage of highly parallel architectures in order to speed up the optimization process. With the development of the adjoint formulation, gradient-based methods for aerodynamic optimization become a promising approach to improve the aerodynamic performance of aircraft designs. The adjoint methodology allows the evaluation the gradients to all design variables of a cost function, such as drag or lift, at the equivalent cost of more or less one CFD simulation. However, some practical problems have been delaying its full implementation to the industry, which can be summarized as: integrability, computer performance, and adjoint robustness. This work tackles some of these issues and analyse them in well-known test cases. As summary, the contributions comprises: • The employment of NURBS as design variables in an automatic optimization loop for the improvement of the aerodynamic performance of aircraft wings in transonic regimen. • The development of point inversion algorithms to calculate the NURBS parametric coordinates from the space coordinates, to link with the computational grid vertex. • The use and validation of the adjoint formulation to calculate the gradients from the surface sensitivities in an automatic optimization loop and evaluate its reliability, compared with finite differences. • This work proposes some algorithms that take advantage of the underlying CAD geometry description, in the form of NURBS patches, to handle intersections and mesh adaptations. • There are not many usable libraries for NURBS available. In this work an open source library DOMINO NURBS has been developed and is offered to the community as free, open source code. • The implementation of a transonic CFD solver from scratch in a graphic card, for an assessment of the implementability of conventional CFD solvers for unstructured grids to highly parallel architectures. • Finally, this research proposes the use of the Green's function as an efficient paralellization scheme of numerical solvers. The presented work has been supported by the activities carried out at the Fluid Dynamics branch of the National Institute for Aerospace Technology (INTA) through national founding research projects: DOMINO, SIMUMAT, and CORESIMULAERO; in line with the activities carried out by the Methods and Tools and Flight Physics department at Airbus and the Group for Aeronautical Research and Technology in Europe (GARTEUR) action group AG/52.

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Elucidating the genetic basis of human phenotypes is a major goal of contemporary geneticists. Logically, two fundamental and contrasting approaches are available, one that begins with a phenotype and concludes with the identification of a responsible gene or genes; the other that begins with a gene and works toward identifying one or more phenotypes resulting from allelic variation of it. This paper provides a conceptual overview of phenotype-based vs. gene-based procedures with emphasis on gene-based methods. A key feature of a gene-based approach is that laboratory effort first is devoted to developing an assay for mutations in the gene under regard; the assay then is applied to the evaluation of large numbers of unrelated individuals with a variety of phenotypes that are deemed potentially resulting from alleles at the gene. No effort is directed toward chromosomally mapping the loci responsible for the phenotypes scanned. Example is made of my laboratory’s successful use of a gene-based approach to identify genes causing hereditary diseases of the retina such as retinitis pigmentosa. Reductions in the cost and improvements in the speed of scanning individuals for DNA sequence anomalies may make a gene-based approach an efficient alternative to phenotype-based approaches to correlating genes with phenotypes.

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Simple sequence repeats (SSRs), consisting of tandemly repeated multiple copies of mono-, di-, tri-, or tetranucleotide motifs, are ubiquitous in eukaryotic genomes and are frequently used as genetic markers, taking advantage of their length polymorphism. We have examined the polymorphism of such sequences in the chloroplast genomes of plants, by using a PCR-based assay. GenBank searches identified the presence of several (dA)n.(dT)n mononucleotide stretches in chloroplast genomes. A chloroplast (cp) SSR was identified in three pine species (Pinus contorta, Pinus sylvestris, and Pinus thunbergii) 312 bp upstream of the psbA gene. DNA amplification of this repeated region from 11 pine species identified nine length variants. The polymorphic amplified fragments were isolated and the DNA sequence was determined, confirming that the length polymorphism was caused by variation in the length of the repeated region. In the pines, the chloroplast genome is transmitted through pollen and this PCR assay may be used to monitor gene flow in this genus. Analysis of 305 individuals from seven populations of Pinus leucodermis Ant. revealed the presence of four variants with intrapopulational diversities ranging from 0.000 to 0.629 and an average of 0.320. Restriction fragment length polymorphism analysis of cpDNA on the same populations previously failed to detect any variation. Population subdivision based on cpSSR was higher (Gst = 0.22, where Gst is coefficient of gene differentiation) than that revealed in a previous isozyme study (Gst = 0.05). We anticipate that SSR loci within the chloroplast genome should provide a highly informative assay for the analysis of the genetic structure of plant populations.

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Il lavoro presentato in questa tesi di Dottorato è incentrato sullo sviluppo di strategie analitiche innovative basate sulla sensoristica e su tecniche di spettrometria di massa in ambito biologico e della sicurezza alimentare. Il primo capitolo tratta lo studio di aspetti metodologici ed applicativi di procedure sensoristiche per l’identificazione e la determinazione di biomarkers associati alla malattia celiaca. In tale ambito, sono stati sviluppati due immunosensori, uno a trasduzione piezoelettrica e uno a trasduzione amperometrica, per la rivelazione di anticorpi anti-transglutaminasi tissutale associati a questa malattia. L’innovazione di questi dispositivi riguarda l’immobilizzazione dell’enzima tTG nella conformazione aperta (Open-tTG), che è stato dimostrato essere quella principalmente coinvolta nella patogenesi. Sulla base dei risultati ottenuti, entrambi i sistemi sviluppati si sono dimostrati una valida alternativa ai test di screening attualmente in uso per la diagnosi della celiachia. Rimanendo sempre nel contesto della malattia celiaca, ulteriore ricerca oggetto di questa tesi di Dottorato, ha riguardato lo sviluppo di metodi affidabili per il controllo di prodotti “gluten-free”. Il secondo capitolo tratta lo sviluppo di un metodo di spettrometria di massa e di un immunosensore competitivo per la rivelazione di prolammine in alimenti “gluten-free”. E’ stato sviluppato un metodo LC-ESI-MS/MS basato su un’analisi target con modalità di acquisizione del segnale selected reaction monitoring per l’identificazione di glutine in diversi cereali potenzialmente tossici per i celiaci. Inoltre ci si è focalizzati su un immunosensore competitivo per la rivelazione di gliadina, come metodo di screening rapido di farine. Entrambi i sistemi sono stati ottimizzati impiegando miscele di farina di riso addizionata di gliadina, avenine, ordeine e secaline nel caso del sistema LC-MS/MS e con sola gliadina nel caso del sensore. Infine i sistemi analitici sono stati validati analizzando sia materie prime (farine) che alimenti (biscotti, pasta, pane, etc.). L’approccio sviluppato in spettrometria di massa apre la strada alla possibilità di sviluppare un test di screening multiplo per la valutazione della sicurezza di prodotti dichiarati “gluten-free”, mentre ulteriori studi dovranno essere svolti per ricercare condizioni di estrazione compatibili con l’immunosaggio competitivo, per ora applicabile solo all’analisi di farine estratte con etanolo. Terzo capitolo di questa tesi riguarda lo sviluppo di nuovi metodi per la rivelazione di HPV, Chlamydia e Gonorrhoeae in fluidi biologici. Si è scelto un substrato costituito da strips di carta in quanto possono costituire una valida piattaforma di rivelazione, offrendo vantaggi grazie al basso costo, alla possibilità di generare dispositivi portatili e di poter visualizzare il risultato visivamente senza la necessità di strumentazioni. La metodologia sviluppata è molto semplice, non prevede l’uso di strumentazione complessa e si basa sull’uso della isothermal rolling-circle amplification per l’amplificazione del target. Inoltre, di fondamentale importanza, è l’utilizzo di nanoparticelle colorate che, essendo state funzionalizzate con una sequenza di DNA complementare al target amplificato derivante dalla RCA, ne permettono la rivelazione a occhio nudo mediante l’uso di filtri di carta. Queste strips sono state testate su campioni reali permettendo una discriminazione tra campioni positivi e negativi in tempi rapidi (10-15 minuti), aprendo una nuova via verso nuovi test altamente competitivi con quelli attualmente sul mercato.

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A infecção por papilomavirus é a principal causa de desenvolvimento de neoplasias intraepiteliais cervicais (NIC) e câncer do colo do útero (CCU). Estudos epidemiológicos têm demonstrado que a persistência do genoma viral encontra-se associado a variantes moleculares específicas de papilomavirus humano (HPV) de alto risco. As moléculas HLA de classe II têm um importante papel na resposta imune. Associações entre HLA e CCU ou infecção por HPV tem sido demonstrado em diferentes populações. O nosso objetivo foi verificar se a variabilidade de HLA-DRB1 e DQB1 estavam associada ao CCU e NIC III em mulheres de Belém, uma população formada pelos 3 principais grupos étnicos humanos e uma área de alto risco para o CCU no Norte do Brasil. Foi investigada a existência de diferenças na distribuição de alelos HLA entre mulheres com CCU e NIC III portadoras de diferentes variantes de HPV-16 e mulheres citologicamente normais. Os genes HLA DQB1 e DRB1 foram tipados pelo método de PCR-SSO em 95 casos e 287 controles de mulheres com citologia normal atendidas em um centro de prevenção do colo do útero na mesma cidade. As variantes de HPV-16 foram tipadas por sequenciamento de um fragmento da região controladora do genoma viral (LCR). O polimorfismo na posição 350 do gene E6 foi tipado baseado em um protocolo de hibridização em pontos, para identificar a alteração na posição 350T→G. A magnitude das associações foi estimada por odds ratio (OR) e os respectivos intervalos de confiança (IC), ajustados para potenciais fatores de confusão. Uma associação positiva foi observada entre CCU e os haplótipos DRB1* 150 l-DQB1*0602, DRB1*04-DQB1*0301 e DRB1*1602-DQB1*0301. Ao contrário, DRB1*01-DQB1*0501 mostrou um efeito protetor. Os alelos DRB1*0804, DQB1*0402 apresentaram efeito protetor contra positividade por HPV. O alelo DQB1*0502 e o grupo DRB1*15 foram positivamente associados. Os nossos resultados mostram que as associações positivas de DRB1*1501 e DRB1*1602 podem ser atribuídas a variantes asiático-americanas quando comparado a variantes européias. O risco conferido a DRB1*1501 foi encontrado associado tanto a variantes E6350G quanto a variantes E6350T, entretanto, o maior efeito foi devido às variantes E6250T. A associação positiva de DRB1*1602 foi significativa somente no grupo de mulheres positivas para E6350G. Estes resultados estão de acordo com a composição étnica da população estudada bem como um maior potencial oncogênico de certas variantes. Nossos dados sugerem que a contribuição dos alelos HLA na susceptibilidade genética ao CCU difere de acordo com a distribuição das variantes de HPV em uma dada região geográfica ou grupo étnico.

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The increasing economic competition drives the industry to implement tools that improve their processes efficiencies. The process automation is one of these tools, and the Real Time Optimization (RTO) is an automation methodology that considers economic aspects to update the process control in accordance with market prices and disturbances. Basically, RTO uses a steady-state phenomenological model to predict the process behavior, and then, optimizes an economic objective function subject to this model. Although largely implemented in industry, there is not a general agreement about the benefits of implementing RTO due to some limitations discussed in the present work: structural plant/model mismatch, identifiability issues and low frequency of set points update. Some alternative RTO approaches have been proposed in literature to handle the problem of structural plant/model mismatch. However, there is not a sensible comparison evaluating the scope and limitations of these RTO approaches under different aspects. For this reason, the classical two-step method is compared to more recently derivative-based methods (Modifier Adaptation, Integrated System Optimization and Parameter estimation, and Sufficient Conditions of Feasibility and Optimality) using a Monte Carlo methodology. The results of this comparison show that the classical RTO method is consistent, providing a model flexible enough to represent the process topology, a parameter estimation method appropriate to handle measurement noise characteristics and a method to improve the sample information quality. At each iteration, the RTO methodology updates some key parameter of the model, where it is possible to observe identifiability issues caused by lack of measurements and measurement noise, resulting in bad prediction ability. Therefore, four different parameter estimation approaches (Rotational Discrimination, Automatic Selection and Parameter estimation, Reparametrization via Differential Geometry and classical nonlinear Least Square) are evaluated with respect to their prediction accuracy, robustness and speed. The results show that the Rotational Discrimination method is the most suitable to be implemented in a RTO framework, since it requires less a priori information, it is simple to be implemented and avoid the overfitting caused by the Least Square method. The third RTO drawback discussed in the present thesis is the low frequency of set points update, this problem increases the period in which the process operates at suboptimum conditions. An alternative to handle this problem is proposed in this thesis, by integrating the classic RTO and Self-Optimizing control (SOC) using a new Model Predictive Control strategy. The new approach demonstrates that it is possible to reduce the problem of low frequency of set points updates, improving the economic performance. Finally, the practical aspects of the RTO implementation are carried out in an industrial case study, a Vapor Recompression Distillation (VRD) process located in Paulínea refinery from Petrobras. The conclusions of this study suggest that the model parameters are successfully estimated by the Rotational Discrimination method; the RTO is able to improve the process profit in about 3%, equivalent to 2 million dollars per year; and the integration of SOC and RTO may be an interesting control alternative for the VRD process.

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Plane model extraction from three-dimensional point clouds is a necessary step in many different applications such as planar object reconstruction, indoor mapping and indoor localization. Different RANdom SAmple Consensus (RANSAC)-based methods have been proposed for this purpose in recent years. In this study, we propose a novel method-based on RANSAC called Multiplane Model Estimation, which can estimate multiple plane models simultaneously from a noisy point cloud using the knowledge extracted from a scene (or an object) in order to reconstruct it accurately. This method comprises two steps: first, it clusters the data into planar faces that preserve some constraints defined by knowledge related to the object (e.g., the angles between faces); and second, the models of the planes are estimated based on these data using a novel multi-constraint RANSAC. We performed experiments in the clustering and RANSAC stages, which showed that the proposed method performed better than state-of-the-art methods.

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Enquadramento – A Early Warning Scores é uma escala de alerta, baseada num sistema de atribuição de pontos (scores) aos parâmetros vitais e deterioração do SNC, sendo a sua principal finalidade a identificação precoce do risco de deterioração fisiológica do doente. Objetivos – Determinar os parâmetros da escala que foram avaliados; identificar a periodicidade de avaliação dos parâmetros da escala; determinar as situações identificadas como risco de deterioração fisiológica; avaliar as propriedades psicométricas da escala Early Warning Scores (validade e fiabilidade). Material e Método – Estudo quantitativo e descritivo-correlacional, cuja população alvo consistiu nos doentes vítimas de acidente ou doença súbita, submetidos a atendimentos por parte de enfermeiros afetos ao INEM, nomeadamente nas ambulâncias de Suporte Imediato de Vida, mediante ativação via 112. O instrumento de avaliação utilizado consiste na Escala Early Warning Scores. Resultados – Verificou-se que o índice de fiabilidade se traduziu num valor de alfa de Cronbach, para a globalidade da escala, fraco (α=0.462). Concluiu-se que houve uma redução progressiva dos scores, em termos de risco, indicando a ocorrência de uma deteção precoce da degradação clínica dos 214 doentes, o que se traduziu numa atuação mais eficaz no pré-hospitalar. Conclusão - A redução progressiva dos scores, em termos de risco ao longo dos três momentos de avaliação com a Early Warning Scores, sugere que houve uma deteção precoce da degradação clínica dos doentes, resultando numa atuação mais eficaz no pré-hospitalar. Palavras-chave: Pré-hospitalar; Risco de deterioração fisiológica; Early Warning Scores.

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"Printed 1994"--T.p. verso.

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An investigation was conducted to evaluate the impact of experimental designs and spatial analyses (single-trial models) of the response to selection for grain yield in the northern grains region of Australia (Queensland and northern New South Wales). Two sets of multi-environment experiments were considered. One set, based on 33 trials conducted from 1994 to 1996, was used to represent the testing system of the wheat breeding program and is referred to as the multi-environment trial (MET). The second set, based on 47 trials conducted from 1986 to 1993, sampled a more diverse set of years and management regimes and was used to represent the target population of environments (TPE). There were 18 genotypes in common between the MET and TPE sets of trials. From indirect selection theory, the phenotypic correlation coefficient between the MET and TPE single-trial adjusted genotype means [r(p(MT))] was used to determine the effect of the single-trial model on the expected indirect response to selection for grain yield in the TPE based on selection in the MET. Five single-trial models were considered: randomised complete block (RCB), incomplete block (IB), spatial analysis (SS), spatial analysis with a measurement error (SSM) and a combination of spatial analysis and experimental design information to identify the preferred (PF) model. Bootstrap-resampling methodology was used to construct multiple MET data sets, ranging in size from 2 to 20 environments per MET sample. The size and environmental composition of the MET and the single-trial model influenced the r(p(MT)). On average, the PF model resulted in a higher r(p(MT)) than the IB, SS and SSM models, which were in turn superior to the RCB model for MET sizes based on fewer than ten environments. For METs based on ten or more environments, the r(p(MT)) was similar for all single-trial models.

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Introduction: In the World Health Organization (WHO) MONICA (multinational MONItoring of trends and determinants in CArdiovascular disease) Project considerable effort was made to obtain basic data on non-respondents to community based surveys of cardiovascular risk factors. The first purpose of this paper is to examine differences in socio-economic and health profiles among respondents and non-respondents. The second purpose is to investigate the effect of non-response on estimates of trends. Methods:Socio-economic and health profile between respondents and non-respondents in the WHO MONICA Project final survey were compared. The potential effect of non-response on the trend estimates between the initial survey and final survey approximately ten years later was investigated using both MONICA data and hypothetical data. Results: In most of the populations, non-respondents were more likely to be single, less well educated, and had poorer lifestyles and health profiles than respondents. As an example of the consequences, temporal trends in prevalence of daily smokers are shown to be overestimated in most populations if they were based only on data from respondents. Conclusions: The socio-economic and health profiles of respondents and non-respondents differed fairly consistently across 27 populations. Hence, the estimators of population trends based on respondent data are likely to be biased. Declining response rates therefore pose a threat to the accuracy of estimates of risk factor trends in many countries.