Dissertations / Theses on the topic 'Control variables'
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Böhm, Walter, and Peter Hackl. "CUSUM Chart for Correlated Control Variables." Department of Statistics and Mathematics, WU Vienna University of Economics and Business, 1991. http://epub.wu.ac.at/76/1/document.pdf.
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The cumulative sum (CUSUM) technique is well-established in theory and practice of process control. A comprehensive exposition of the method is given, e.g., by Wetherill and Brown (1991). A question that is seldom treated in the literature is that on the effect of serial correlation of the control variable. Johnson and Bagshaw (1974) investigate the effect of correlation on the run length distribution when the control variable follows a first order autoregressive or moving average process. They also give an approximate expression for the average run length of the CUSUM- technique for correlated control variables. In this paper we derive an exact expression for the average run length of a discretized CUSUM-technique, i.e., a technique that uses a scoring system for the observations of the control variable. The scoring system is that suggested by Munford (1980). Our results are derived for a control variable that is assumed to follow a first order autoregressive process and with normally distributed disturbances. After deriving in Section 2 the expression for the average run length we discuss its dependence on the process parameter and give a numerical illustration. In Section 3 we discuss corrections for the CUSUM-technique in order to keep the nominal risk for an out-of-control decision and compare our results with those given by Johnson and Bagshaw (1974). (author's abstract)Series: Forschungsberichte / Institut für Statistik
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Nandong, Jobrun. "Modelling and control strategies for extractive alcoholic fermentation: partial control approach." Thesis, Curtin University, 2010. http://hdl.handle.net/20.500.11937/2197.
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The vast majority of chemical and bio-chemical process plants are normally characterized by large number of measurements and relatively small number of manipulated variables; these thin plants have more output than input variables. As the number of manipulated variables restricts the number of controlled variables, thin plant has presented a daunting challenge to the engineers in selecting which measured variables to be controlled. In general, this is an important problem in modern process control today, because controlled variables selection is one of the key questions which must be carefully addressed in order to effectively design control strategies for process plants. While the issue relating to controlled variables selection has remained the key question to be resolved since the articulation of CSD problem by Foss in 1970s, the work described in this thesis points out to another equally important question in CSD, that is, what is the sufficient number of controlled variables required? Thinking over this question leads one to the necessity for gaining a rational understating of the governing principle in partial control design, namely the variables interaction.In this thesis, we propose a novel data-oriented approach to solving the control structure problem within the context of partial control framework. This approach represents a significant departure from the mainstream methods in CSD, which currently can be broadly classified into two major categories as the mathematical-oriented and heuristic-hierarchical approaches. The key distinguishing feature of the proposed approach lies in its adoption of technique based on the Principal Component Analysis (PCA), which is used to systematically determine the suitable controlled variables. Conversely, the determination of the controlled variables in mathematical-oriented and heuristic-hierarchical approaches is done via the mathematical optimization and process knowledge/engineering experience, respectively. It is important to note that, the data-oriented approach in this thesis emerges from the fusion of two important concepts, namely the partial control structure and PCA. While partial control concept provides the sound theoretical framework for addressing the CSD problem in a systematic manner, the PCA-based technique helps in determining not only the suitable controlled variables but also the sufficient number of controlled variables required.Since the classical framework of partial control is not amendable to a systematic way in the identification of controlled variables, it is necessary to develop a new framework of partial control in this thesis. Within this new framework the dominant variable can be clearly defined, and which in turn allows the incorporation of PCA-based technique for the systematic identification of controlled variables.The application of the data-oriented approach is demonstrated on a nonlinear multivariable bioprocess case study, called the two-stage continuous extractive (TSCE) alcoholic fermentation process. The system consists of 5 interlinked units: 2 bioreactors in series, a centrifuge, vacuum flash vessel and treatment tank. The comparison of the two-stage design with that of single-stage design reported in literature shows that: (1) both designs exhibit comparable performance in term of the maximum allowable trade-off values between yield and productivity, and (2) two-stage design exhibits stronger nonlinear behaviour than that of single-stage. Thus, the design of control strategies for the former is expected to be more challenging.Various partial control strategies are developed for the case study, such as basic partial control strategy, complete partial control strategies with and without PID enhancement technique and optimal size partial control strategy. Note that, this system consists of 16 output variables and only 6 potential manipulated variables, which has approximately 4,000,000 control structure alternatives. Therefore, the application of mathematical approach relying on optimization is not practical for this case study – i.e. assuming that evaluation of each alternative takes 30 seconds of optimization time, thus, complete screening will require almost 4 years to complete.Several exciting new insights crystallize from the simulation study performed on the case study, where two of them are most important from the perspective of effective design of partial control strategy: 1) There is an optimal size of partial control structure where too many controlled variables can lead to the presence of bottleneck control-loop, which in turn can severely limit the dynamic response of overall control system. On the other hand, too few controlled variables can lead to unacceptable variation or loss in performance measures. 2) The nature of variables interaction depends on the choice of control structure. Thus, it is important to ensure that the nature of open-loop variables interaction is preserved by the implementation of a particular control strategy. When this is achieved, then we say that this control system works synergistically with the inherent control capability of a given process – i.e. achieving the synergistic external-inherent control system condition.The proposed approach has been successfully applied to the case study, where the optimal partial control structure is found to be 3x3 i.e. 3 controlled variables are sufficient to meet all 3 types of control objectives: overall (implicit) performance objectives, constraint and inventory control objectives. Finally, the proposed approach effectively unifies the advantages of both mathematical-oriented and heuristic-hierarchical approaches, and while at the same time capable of overcoming many limitations faced by these two mainstream approaches.
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Clerget, Charles-Henri. "Contributions au contrôle et à l'optimisation dynamique de systèmes à retards variables." Thesis, Paris Sciences et Lettres (ComUE), 2017. http://www.theses.fr/2017PSLEM053/document.
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Dans cette thèse, nous avons étudié le contrôle et l'optimisation de systèmes dynamiques sujets à des retards variables.L'existence de retards, de commande ou d'état, est un problème classique en automatique, susceptible de réduire les performances du système en régime transitoire, voire de remettre en cause la stabilité de contrôleurs en boucle fermée. De tels phénomènes de retards variables jouent un rôle important dans de nombreuses applications en génie des procédés.Dans une première partie, nous avons étudié la régulation en boucle fermée d'un système soumis à des retards de métrologie variables et incertains. Nous avons établi de nouveaux résultats garantissant la stabilité robuste sous certaines conditions explicites sur le gain du contrôleur. Dans une seconde partie, nous avons abordé le problème de l'optimisation dynamique de systèmes présentant des retards variables dépendant de la commande liés à des phénomènes de transport dans des réseaux hydrauliques. Nous avons proposé un algorithme itératif d'optimisation et garanti sa convergence grâce à une analyse détailléeThis Ph.D. work studied the control and optimization of dynamical systems subject to varying time delays.State and control time delays are a well-known problem in control theory, with a potential to decrease performances during transient regimes, or even to jeopardize controllers closed-loop stability. Such variable delays play a key role in many applications in process industries.In a first part, we studied the closed-loop control of a system subject to varying and uncertain metrology delays. We established new results on robust stability under explicit conditions on the controller gain. In a second part, we tackled the problem of the dynamic optimization of systems exhibiting input dependent delays due to transport phenomena in complex hydraulic architectures. We designed an iterative optimization algorithm and guaranteed its convergence through a detailed analysis
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Huang, Yi. "CONTROL OF METAL TRANSFER AT GIVEN ARC VARIABLES." UKnowledge, 2011. http://uknowledge.uky.edu/ece_etds/4.
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Gas Metal Arc Welding (GMAW) is one of the most important welding processes in industrial application. To control metal transfer at given variables is a focus in the field of research and development in welding community.
In this dissertation, laser enhanced GMAW is proposed and developed by adding a lower power laser onto the droplet to generate an auxiliary detaching force. The electromagnetic force needed to detach droplets, thus the current that determines this force, is reduced. Wire feed speed, arc voltage, and laser intensity were identified as three major parameters that affect the laser enhanced metal transfer process and a systematic series of experiments were designed and conducted to test these parameters. The behaviors of the laser enhanced metal transfer process observed from high speed images were analyzed using the established physics of metal transfer. In all experiments, the laser was found to affect the metal transfer process as an additional detaching force that tended to change a short-circuiting transfer to drop globular or drop spray, reduce the diameter of the droplet detached in drop globular transfer, or decrease the diameter of the droplet such that the transfer changed from drop globular to drop spray. The enhancement of the laser was found to increase as the laser intensity increased. The larger laser intensity tended to help reduce the size of the droplet detached. The arc voltage affected the metal transfer process through changing the current and changing the gap and possible time interval of the droplet development. A larger arc voltage helped reduce the size of the droplet detached through an increased electromagnetic force. Desired heat input and current/arc pressure waveforms may thus be both delivered and controlled by GMAW through laser enhancement. Laser recoil pressure force was estimated based on the difference of gravitational force with and without laser pulse, and the result was with an acceptable accuracy. Good formation of welds and full penetration of thin plate could be obtained using laser enhanced GMAW. A nonlinear model was established to simulate the dynamic metal transfer in laser enhanced GMAW, and the results agree with the experimental one.
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Wise, Marshall Alan. "Simultaneous process control of several independent quality variables." Thesis, Virginia Tech, 1990. http://hdl.handle.net/10919/41532.
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A method for multivariate quality control with the dual objectives of providing a true level of sampling error probabilities for the joint control of several quality variables while also giving problem diagnoses for the quality variables individually. The method is comprised of an afine transformation of the multiple quality variables which creates a univariate test statistic used to monitor the quality and provide problem diagnoses. In practice, realized values of this statistic would be plotted as a time series on a control chart with multiple diagnosis intervals. For the analysis of the method’s effectiveness, the quality variables are assumed to be independent and normally distributed.
The method is shown to be successful in achieving desired sampling error probabilities for any m quality variables in the case of positive shifts in the means of the variables. A second transformed variable is added for the diagnosis of shifts of unrestricted direction, and its effectiveness is analyzed. The sample size requirement of the afine transformation method is compared to the total sample size necessary when a separate Shewhart chart for the mean is maintained for each quality variable with the same overall sampling plan objectives. The power of the method to detect quality problems in general while disregarding specific diagnoses is compared to the power of Hotelling’s T² test for multivariate quality control. A comprehensive evaluation of the relative worth of the two methods is not possible since the T² statistic does not consider diagnoses of the individual quality variables.Master of Science
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García, Bustos Sandra Lorena. "Control Multivariante Estadístico de Variables Discretas tipo Poisson." Doctoral thesis, Universitat Politècnica de València, 2014. http://hdl.handle.net/10251/40592.
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En algunos casos, cuando el número de defectos de un proceso de producción tiene que ser controlada, la distribución de Poisson se emplea para modelar la frecuencia de estos defectos y para desarrollar un gráfico de control. En este trabajo se analiza el control de características de calidad p> 1 de Poisson . Cuando este control se necesita, hay dos enfoques principales: 1 - Un gráfico para cada variable de Poisson, el esquema múltiple.. 2 -. Sólo una gráfico para todas las variables, el sistema multivariable. En este trabajo se desarrolla un nuevo gráfico de control multivariable basado en la combinación lineal de las variables de Poisson, donde esta combinación lineal es optimizada con el fin de mantener un ARL bajo control deseado y de minimizar el ARL fuera de control. Esta optimización se lleva a cabo utilizando un software bajo Windows ©, que también hace una comparación de rendimiento entre este gráfico y otros sistemas para monitorear una serie de variables Poisson. En los otros sistemas se incluye la suma de las variables (gráfico MP) y un conjunto optimizado de gráficos univariados Poisson (esquema múltiple).García Bustos, SL. (2014). Control Multivariante Estadístico de Variables Discretas tipo Poisson [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/40592
TESIS
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Keating, Katrina Ann. "Noncognitive Variables for Placement| A Randomized Control Trial." Thesis, San Francisco State University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10822840.
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This study was born out of a concern that U.S. community colleges were currently using or considering using noncognitive variables for academic placement without an understanding of how students would react to these scales in a high-stakes setting. While the use of noncognitive variables for placement often stems from a desire to overcome the myriad of limitations of content-based placement tests, the researcher was concerned that noncognitive variables had the potential to become an extension of the problems caused by the test.
This study was guided by two research questions: How does the high-stakes nature of academic placement impact student responses on noncognitive scales? How does the context, demand, characteristics, and framing of the noncognitive variables impact stereotype threat, if at all? The researcher performed a random control trial of incoming community college students to determine how they might react to questions about noncognitive variables. One group was told their responses would be used for placement, and the other was told that their responses would be used to improve instruction.
The major findings suggest that initial framing played a role in participant responses and lowered responses on some noncognitive variables, but that the act of having taken a placement test was also a moderator of student behavior and whether or not students believed the initial framing. Stereotype threat susceptibility appeared to have a statistically significant relationship with some participants’ responses on some noncognitive scales, and there was evidence that initial framing was not related. Finally, while participants were generally honest, those who did change their answers did so in a manner that was inconsistent, more so when given high stakes framing.
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MARANHAO, PAULO HENRIQUE COELHO. "CONTROL CHARTS ON TRANSFORMED VARIABLES FOR MONITORING MULTIVARIATE PROCESS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2012. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=21881@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROA maioria dos trabalhos que propõem esquemas de Controle Estatístico de Processos Multivariados (CEPM) e que analisam o desempenho desses esquemas considera alterações nas variáveis observadas. Alguns autores mostraram que, quando alterações no vetor de médias de um processo multivariado ocorrem tipicamente em direções previsíveis, a estatística mais eficaz para o monitoramento do processo é o valor da projeção do vetor de observações (ou de sua média amostral) em cada uma dessas direções. Este trabalho propõe um método para o monitoramento de processos multivariados nos quais alterações nos parâmetros do processo são devidas a causas especiais que afetam variáveis não observáveis e ocorrem em direções conhecidas (ortogonais), e compara seu desempenho com o de gráficos de Shewhart nas variáveis observadas, nas componentes principais, e com o de gráficos de T2 no vetor de variáveis observadas. Além disso, é proposto um esquema complementar de monitoramento para detectar alterações em novas direções fora do hiperplano formado pelas direções conhecidas. Resultados obtidos por simulação mostram que o esquema proposto, de gráficos de controle em variáveis transformadas (projeções do vetor de variáveis observadas nas direções conhecidas), tem melhor desempenho na maior parte dos casos analisados. A análise de desempenho é feita supondo deslocamentos da média nas direções conhecidas (já que estes é que são as alterações conhecidas, ocasionadas pelas causas especiais) e/ou aumentos da variância nessas mesmas direções. A comparação é baseada nas probabilidades de alarme falso e de alarme verdadeiro.
Most of the works that propose schemes of Multivariate Statistical Process Control (MSPC) and that analyze the performance of these schemes consider changes in the observed variables. Previous authors have shown that when the shifts in the mean vector of a multivariate process typically occur in predictable directions, the most effective statistics for process monitoring are the values of the projections of the vector of observations (or of the sample average vector) in each of these directions. This paper proposes a method for the monitoring of multivariate processes in which changes in the process parameters are due to special causes that affect non-observable variables and occur in (orthogonal) known directions, and compares its performance with that of Shewharts charts on the observed variables, on the principal components, and with that of T2 charts on the vector of observed variables. In addition, it is proposed a supplementary scheme of monitoring to detect changes in new directions outside of the hyperplane formed by known directions. Results obtained by simulation show that the proposed scheme, consisting of control charts on the transformed variables (projections of the vector of observed variables on the known directions), has better performance in most of the cases analyzed. The analysis of performance is done assuming shifts in the mean of the known directions (since these are the known changes associated to special causes) and/or increases of the variance in these same directions. The comparisons are based on the in-control and out-of-control probabilities of signal.
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Crisóstomo, Tiago Miguel Jacinto. "Firm performance and corporate governance variables - United Kingdom." Master's thesis, Instituto Superior de Economia e Gestão, 2013. http://hdl.handle.net/10400.5/11064.
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Mestrado em FinançasA temática do corporate governance remonta ao século XVIII. Apesar disso, só depois da crise financeira da década de 2000 que afectaram todo o sistema e das graves falências empresariais, o tema voltou à ribalta. Este estudo revisita de forma abrangente a evolução das várias teorias da empresa à luz do desenvolvimento do corporate governance como ciência fundamental para promover e desenvolver a performance no meio empresarial. Para tal, foi analisado o efeito que as variáveis de corporate governance têm na performance das empresas do Reino Unido no período de 2005-2012. Foram considerados cinco mecanismos de controlo empresarial: controlo efectuado aos directores, controlo através da estrutura accionista, controlo interno efectuado pelos "Committees", atribuição do cargo de CEO e Chairman a pessoas distintas e controlo através de remuneração baseada na performance. A estrutura accionista, aliada à atribuição do cargo de CEO e Chairman a pessoas distintas e o controlo através da remuneração baseada na performance, revelaram-se os mecanismos mais significativos na resolução da equação performance governance. Finalmente, e baseado na revisão de literatura e nos resultados obtidos, é possível afirmar que o corporate governance é um processo dinâmico no qual todos os intervenientes devem ser tidos em conta na prossecução do objectivo comum desenvolver um modelo de governance que seja sustentável e benéfico para a sociedade.
The theme of corporate governance dates back to the eighteenth century. Nevertheless, only after the financial crisis in 2000's decade that affected the entire system and the devastating corporate failures, the subject returned to the spotlight. This study revisits in a comprehensive way the evolution of the different theories of the firm in light of the development of corporate governance, as a fundamental science to promote and develop the corporate performance. To this purpose, we examined the effect that corporate governance variables have on the performance of companies in the UK for the period 2005-2012. We considered five mechanisms of corporate control: Board of directors, equity ownership structure, internal control performed by the Board Committees, separation of CEO and Chairman roles, and control through the variable remuneration. Board ownership, together with the separation of CEO and Chairman roles and control through the performance variable remuneration, proved to be the most significant mechanisms in the resolution of the equation performance - governance. Finally, and based on the literature review and the results obtained, it can be stated that corporate governance is a dynamic process in which the different stakeholders should be taken into account in order to achieve a common goal - develop a governance model that is sustainable and beneficial to society.
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Hanson, Robert Alexander. "The application of a single control chart for dependent variables in multivariate quality control." Thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-05022009-040726/.
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Saona, Urmeneta Raimundo Julián. "Prophet inequality through schur-convexity and optimal control." Tesis, Universidad de Chile, 2019. http://repositorio.uchile.cl/handle/2250/168161.
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Tesis para optar al grado de Magíster en Ciencias de la Ingeniería, Mención Matemáticas AplicadasMemoria para optar al título de Ingeniero Civil Matemático
En el clásico problema de tiempo de parada óptimo conocido como Desigualdad del profeta realizaciones de variables positivas e independientes son descubiertas secuencialmente. Una jugadora que conoce las distribuciones, pero no puede ver en el futuro, debe decidir cuándo parar y tomar la última variable revelada. Su objetivo es maximizar la esperanza de lo obtenido y su rendimiento está dado por el peor caso del cociente entre la esperanza de que obtiene y la esperanza de lo que obtendría un profeta (que puede ver en el futuro y así siempre elegir el máximo). En los setenta, Krengel y Sucheston, y Garling, [16] determinaron que el rendimiento de una jugadora puede ser una constante y que 1/2 es la mejor constante. En la última década, la desigualdad del profeta ha resurgido como un problema importante dada su conexión con "Posted Price Mechanisms", una teoría usada en ventas en línea. Una variante de particular interés es "Prophet Secretary", donde la única diferencia es que las relaciones son descubiertas en orden aleatorio. Para esta variante, varios algoritmos logran un rendimiento de 1 − 1/e ≈ 0.63 y recientemente Azar et al. [2] mejoraron este resultado. En cuanto a cotas superiores, se sabe que una jugadora no puede hacerlo mejor que 0.745, en el límite sobre el tamaño de la instancia. En esta tesis se deriva una forma de analizar estrategias que dependen sólo del tiempo: dada una instancia, se calcula una secuencia decreciente de exigencias que son usadas para decidir si parar o no. La jugadora tomará el primer valor que supere la exigencia correspondiente al momento en que fue descubierta. Específicamente, se considera una clase robusta de estrategias que denominamos "blind strategies". Constituyen una generalización de fijar una sola exigencia para todo el proceso y consisten en fijar una función, independiente de la instancia, que determina cómo calcular las exigencias una vez la instancia es conocida. El resultado principal es que la jugadora logra un rendimiento de al menos 0.669, superando el estado del arte (Azar et al. [2]) tanto para "Prophet Secretary" como para la variante en la que la jugadora tiene la libertad de escoger el orden en que descubre las variables (Beyhaghi et al [3]). El análisis se reduce a estudiar la distribución del tiempo de parada inducido por estas estrategias, a través de la teoría de Schur-convexidad. También, se demuestra que este tipo de estrategias no pueden lograr más que 0.675, a través de calcular el rendimiento óptimo de la jugadora contra dos instancias particulares, resolviendo un problema de control óptimo. Finalmente, se demuestra que el conjunto más amplio de estrategias no adaptativas no pueden lograr más de √3 − 1 ≈ 0.73, cota que también mejora el estado del arte en cotas superiores para estrategias simples (Azar et al [2]). Se considera una estrategia como no adaptativa si al decisión de parar depende del valor, la identidad y el tiempo en que fue descubierta la variable, pero no toma en cuenta la identidad de las variables anteriores.
CONICYT-Chile, ECOS-CONICYT, Google y CMM - Conicyt PIA AFB170001
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Henn, Santiago Martín. "Sistema de filtrado por electrocoagulación, control y monitoreo de variables." Bachelor's thesis, Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales, 2017. http://hdl.handle.net/11086/6259.
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Proyecto Integrador (IE)--FCEFN-UNC, 2017Desarrolla un sistema que permita, a través del monitoreo y control de variables especificas (temperatura, presión, tensión, corriente y toma de imágenes por CCD) realizar el proceso de electromagnético de partículas de una solución, ademas debe recolectar los datos necesarios para validar un modelo matemático del mismo. Dicho sistema tendré como objetivo superar pruebas de laboratorio y de campo con la mayor efectividad posible
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Bastidas, Valenzuela Silvia Cecilia. "Control de variables en la producción de chocolate fino enriquecido." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2017. https://hdl.handle.net/20.500.12672/6574.
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Determina las variables para el enriquecimiento nutricional del chocolate con el aprovechamiento de la harina de tarwi. Esta semilla ha sido procesada adecuadamente y se han obtenido 4 tipos de harina, se ha realizado pruebas de mezclado con el chocolate fino en diferentes proporciones, siendo su valor proteínico original del chocolate según ficha técnica de 4g/100g incrementándose a 6.26g/100g. Se obtiene un producto de alto valor proteínico como resultado un incremento en 57% proteínas. Se conserva las propiedades organolépticas básicas, se mejora el sabor y textura del mismo con un control estricto de variables en la producción de la harina de tarwi, desde el desamargado, secado, molienda y tamizaje para la obtención de una adecuada harina con contenido de humedad. En el desarrollo experimental se realizó el control de variables que afectan significativamente al chocolate: temperatura de trabajo (38 -42 °C) de fusión del chocolate y de la cámara de refrigeración (9°C) con un tiempo no mayor a 10 minutos de enfriamiento. En las pruebas de viscosidad, se obtienen resultados favorables para las concentraciones ofrecidas de hasta 4.8% de harina de tarwi en chocolate Se realizaron pruebas de evaluación sensorial y se analizaron los resultados al 95% de confianza utilizando el paquete estadístico Minitab 17,de las cuales se obtuvo mayor preferencia por el chocolate enriquecido por el grano desamargado con cascara cocido, así mismo, se realizaron pruebas de análisis proximal y análisis microbiológico en el laboratorio Cerper, obteniéndose óptimos los resultados presentados.Tesis
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Abi, Assali López Wuendy Y. "Optimal selection of measurements and manipulated variables for production control." College Park, Md.: University of Maryland, 2008. http://hdl.handle.net/1903/8780.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2008.Thesis research directed by: Dept. of Chemical and Biomolecular Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Nouasse, Houda. "Gestion supervisée de systèmes étendus à retards variables : cas des réseaux hydrographiques." Thesis, Toulouse, INPT, 2015. http://www.theses.fr/2015INPT0001/document.
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De part et d’autre de la Terre, on observe de plus en plus de phénomènes naturels dévastateurs, parmi lesquels les inondations constituent l’une des catastrophes les plus fréquentes. Ces dernières décennies d’importantes inondations ont été induites par les crues de rivières. Ces crues, dues à des pluies excessives ou aux eaux de ruissellement, causent sans cesse des pertes de vies humaines et des dégâts matériels importants. Pour remédier à ces problèmes, les réseaux hydrographiques sont de plus en plus équipés de moyens de détection de crues. Un facteur essentiel à la gestion de tels phénomènes est la réactivité. En effet, les gestionnaires des réseaux hydrographiques, dans ce genre de situation, doivent prendre rapidement des décisions importantes dans un contexte incertain, car la plupart de ces crues sont le fruit de phénomènes climatiques brusques, dont l’ampleur est difficile à évaluer avec précision. Nous proposons, dans ce mémoire, une méthode de gestion des crues dans des réseaux hydrographiques équipés de zones inondables contrôlées par des portes gravitationnelles. Dans un premier temps, nous avons modélisé notre méthode de gestion à l’aide d’un réseau de transport statique. Dans un second temps, nous l’avons enrichi en utilisant les réseaux de transport à retards dans le but de prendre en compte les temps de déplacement de la ressource gérée. Afin de pallier le problème de la taille importante des réseaux de transport à retards, nous avons élaboré un mécanisme de substitution combinant un réseau de transport statique réduit et une matrice de temporisation. De plus, ce mécanisme autorise la prise en compte des temps de transfert variables dépendant des débits, sans modification ni du réseau de transport, ni de la structure de la matrice de temporisation. Ce mécanisme permet donc une gestion simplifiée des temps de transferts, variables ou non. Avec ce mécanisme, l’évaluation du flot maximal à coût minimum, nous a permis, suivant les stratégies de gestion considérées, de consigner l’ouverture des portes des zones inondables afin d’écrêter la crue mais aussi afin de restituer cette eau stockée au moment opportun. Finalement, afin d’évaluer les apports de cette gestion, la méthode a été appliquée sur un cas d’étude basée sur un tronçon de rivière équipé de trois zones inondables et modélisé à l’aide de simulateurs hydrauliques combinant les approches de modélisation 1D et 2D. Les résultats de simulation obtenus ont montré que l’approche proposée permettait de réduire de manière significative les inondations en aval des cours d’eauOn either side of the Earth, we observe more and more devastating natural phenomena. Amon these phenomena, floods are one of the most frequent and devastating natural disasters. During these last decades extensive flooding were caused by the flood of rivers. These floods due to excessive rainfall or runoff induce invariably the loss of human lives and material damages. To overcome these problems, water systems are increasingly equipped with means for detecting floods. A key factor in the management of such phenomena is responsiveness. Indeed, managers of river systems, faced to this kind of situation should quickly take important decisions in an uncertain context, as most of these floods are induced by abrupt climate events, whose magnitude is difficult to assess accuracy. We propose in this dissertation, a method of flood management in river systems equipped with flood zones controlled by gravitational gates. At first, we modeled our management method using a static transportation network. In a second step, we enriched it by using transportation networks with delays in order to take into account the travel time of the managed resource. The main difficulty of transportation networks with delays is their oversize. To overcome this problem, we developed an alternative mechanism combining a static reduced transportation network with a temporization matrix. Furthermore, this mechanism allows the consideration of variable time transfer depending on flows, without modification either on the transportation network, or on the structure of the temporization matrix. This mechanism allows simplified management of the transfer times, variable or not. With this mechanism, the evaluation of the minimum cost maximum flow allowed us, according to the management strategies considered, to compute the gate opening for floodplains in order to mitigate the flood but also to restore the water stored at the relevant time. Finally, to evaluate the contributions of this management, the method was applied to a case study based on a section of river equipped with three flood control reservoirs areas modeled using hydraulic simulators combining 1D and 2D models. The simulation results showed that the proposed approach allowed reducing significantly the floods downstream watercourses
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Gillespie, Christopher R. "Psychological variables in the self-regulation of diabetes mellitus." Thesis, University of Sheffield, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310882.
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McWilliams, Kyle Grant. "An analysis of variables affecting instructional efficiency." Thesis, University of Canterbury. School of Education, 2006. http://hdl.handle.net/10092/1046.
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A lot about the learning process still remains unknown. The experiments described in this thesis investigated variables that affect instructional efficiency by employing specifically programmed computers to manage and control instructional variables within each experiment for 6- to 7-year old children. A Measurement Procedures Study was undertaken to ascertain when a response should be classified as "acquired." It was decided to classify a response as acquired if it could be performed correctly (without prompting) seven days after instruction. A review of the relationship between accuracy level during instruction and the rate of acquisition found that higher accuracy levels during instruction tend to be associated with higher rates of acquisition provided that non-copying prompting procedures are employed. The first experiment investigated the relationship between accuracy level during instruction and rate of acquisition by presenting a non-copying antecedent prompt (model of the correct spelling word) depending on a preselected target accuracy level. As an error-contingent prompt (model of the correct spelling word) was also provided it could not be ascertained whether transfer of stimulus control occurred as a result of the antecedent prompt, or the error-contingent prompt, or both. The second experiment was a repeat of the first experiment with the error-contingent prompt removed. It was found that it was possible to manage, although not completely control, the accuracy level during instruction by presenting a simultaneous non-copying prompt and that higher accuracy levels during instruction were associated with higher rates of acquisition. A review that examined the error-correction research found that a variety of correction procedures were effective. However, none of the 36 experiments which were reviewed controlled the number of response opportunities. Experiment 3 compared the effects on rate of acquisition of presenting an antecedent model or an error-contingent model. The results of Experiment 3 showed that when the number of learning opportunities was controlled there was little difference in effectiveness or efficiency between an antecedent model and an error-contingent model. Experiment 4 compared the effects of presenting an error-contingent model against an error-contingent model and a secondary response opportunity. It was found that an error-contingent model was at least as effective, although it was overall less efficient when response opportunities were controlled. A supplementary analysis was undertaken to review and compare the results obtained across the four experiments. Across experiments each newly acquired spelling response required about five practice responses, on average. It appears this was a critical variable for acquisition. Additionally, each acquired response was acquired over a two-day period. Although rates of acquisition differed between high-achieving children and low-achieving children, there was little difference in the number of practice responses required for acquisition between these two groups. It was observed that most of the 6- to 7-year old participants found error feedback aversive and this appeared to result in reduced attention to models of the correct spelling when these occurred following errors. The results from this series of investigations suggest that an opportunity for the transfer of stimulus control from the prompt (model of the correct spelling) to the practice stimulus (the spoken word) is more critical for acquisition than where the prompt occurs within the trial (that is, the antecedent or consequent position). It was suggested that future research could investigate (a) the variables which are necessary for the transfer of stimulus control, (b) the generality of the observation that children require five practice responses in order to acquire discrete academic responses, and (c) the effects on rates of acquisition and instructional efficiency of varying the distribution in time of practice responses for children who are learning various types of academic skills.
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Perrin, Christopher J. "FURTHER ANALYSIS OF VARIABLES THAT AFFECT SELF-CONTROL WITH AVERSIVE EVENTS." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1277816514.
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Anderson, Joseph C. "Walking to reach information variables and control strategies for nested actions /." [Bloomington, Ind.] : Indiana University, 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3344558.
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Thesis (Ph.D.)--Indiana University, Dept. of Psychological and Brain Sciences and the Dept. of Cognitive Science, 2009.Title from PDF t.p. (viewed on Oct. 7, 2009). Source: Dissertation Abstracts International, Volume: 70-02, Section: B, page: 1371. Adviser: Geoffrey P. Bingham.
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Venigella, Pavan Kumar. "Robust Mechanism synthesis with random and interval variables." Diss., Rolla, Mo. : University of Missouri-Rolla, 2007. http://scholarsmine.mst.edu/thesis/pdf/Venigella_09007dcc8046c1ff.pdf.
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Thesis (M.S.)--University of Missouri--Rolla, 2007.Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed March 27, 2008) Includes bibliographical references (p. 86-89).
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Li, Bin. "Optimal control problems with constraints on the state and control and their applications." Thesis, Curtin University, 2011. http://hdl.handle.net/20.500.11937/2123.
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In this thesis, we consider several types of optimal control problems with constraints on the state and control variables. These problems have many engineering applications. Our aim is to develop efficient numerical methods for solving these optimal control problems.In the first problem, we consider a class of discrete time nonlinear optimal control problems with time delay and subject to constraints on states and controls at each time point. These constraints are called all-time-step constraints. A constraint transcription technique in conjunction with a local smoothing method is used to construct a sequence of approximate discrete time optimal control problems involving time delay in states and controls and subject to nonlinear inequality constraints in canonical form. These approximate optimal control problems are special cases of a general discrete time optimal control problems with time delay appearing in the state and control and subject to nonlinear inequality constraints in canonical form. Thus, we devise an efficient gradient-based computational method for solving this general optimal control problem.The gradient formulas needed for the cost and the canonical constraint functions are derived. With these gradient formulas, the discrete time optimal control problem with time delay appearing in states and controls and subject to nonlinear inequality constraints in canonical form is solvable as an optimization problem with inequality constraints by the Sequential Quadratic Programming (SQP) method. With this computational method, each of the approximate problems constructed from the original optimal control problem can be solved. A practical problem arising from the study of a tactical logistic decision analysis problem is considered and solved by using the computational method that we have developed.In the second problem, we consider a general class of maximin optimal control problems, where the violation avoidance of the continuous state inequality constraints is to be maximized. An efficient computational method is developed for solving this general maximin optimal control problem. In this computational method, the constraint transcription method is used to construct a smooth approximate function for each of the continuous state inequality constraints, where the accuracy of the approximation is controlled by an accuracy parameter. We then obtain a sequence of smooth approximate optimal control problems, where the integral of the summation of these smooth approximate functions is taken as its cost function.A necessary condition and a sufficient condition are derived showing the relationship between the original maximin problem and the sequence of the smooth approximate problems. We then construct a violation avoidance function from the solution of each of the smooth approximate optimal control problems and the original continuous state inequality constraints in such a way that the problem of finding an optimal control of the maximin optimal control problem is equivalent to the problem of finding the largest root of the violation avoidance function. The control parameterization technique and a time scaling transform are applied to these smooth approximate optimal control problems. Two practical problems are considered as applications. The first one is an obstacle avoidance problem of an autonomous mobile robot, while the second one is the abort landing of an aircraft in a windshear downburst. The proposed computational method is then applied to solve these problems.In the third problem, we consider a class of optimal PID control problems subject to continuous inequality constraints and terminal equality constraint. By applying the constraint transcription method and a local smoothing technique to these continuous inequality constraint functions, we construct the corresponding smooth approximate functions. We use the concept of the penalty function to append these smooth approximate functions to the cost function, forming a new cost function. Then, the constrained optimal PID control problem is approximated by a sequence of optimal parameter selection problems subject to only terminal equality constraint. Each of these optimal parameter selection problems can be viewed and hence solved as a nonlinear optimization problem. The gradient formulas of the new appended cost function and the terminal equality constraint function are derived, and a reliable computation algorithm is given. The method proposed is used to solve a ship steering control problem.In the fourth problem, we consider a class of optimal control problems subject to equality terminal state constraints and continuous inequality constraints on the state and/or control variables. After the control parameterization together with a time scaling transformation, the problem is approximated by a sequence of optimal parameter selection problems with equality terminal state constraints and continuous inequality constraints on the state and/or control. An exact penalty function is constructed for these terminal equality constraints and continuous inequality constraints. It is appended to the cost function to form a new cost function, giving rise to an unconstrained optimal parameter selection problem. The convergence analysis shows that, for a sufficiently large penalty parameter, a local minimizer of the unconstrained optimization problem is a local minimizer of the optimal parameter selection problem with terminal equality constraints and continuous inequality constraints. The relationships between the approximate optimal parameter selection problems and the original optimal control problem are also discussed. Finally, the method proposed is applied to solve three nontrivial optimal control problems.
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Arroyo, Sáez José Nicolás. "Identificación de variables eléctricas de condición para el monitoreo de microcentrales." Tesis, Universidad de Chile, 2014. http://www.repositorio.uchile.cl/handle/2250/116968.
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Ingeniero Civil EléctricoEn el último tiempo el aumento de la demanda no ha ido de la mano con el crecimiento de la oferta, entre lo que sobresalen las barreras a la construcción de proyectos de gran envergadura. Sin embargo, Chile posee un enorme potencial energético, en especial, la energía hidráulica, la cual puede ser una alternativa para desarrollar proyectos de baja escala y responder al desafío de generación. El objetivo de esta memoria es desarrollar un sistema de monitoreo de variables eléctricas, que permita identificar condiciones anormales del funcionamiento de generadores sincrónicos, además disponer de una plataforma en tiempo real que pueda obtener los datos necesarios, para luego ser procesados e identificar posibles fallos. Para esto fue desarrollado un sistema en LABVIEW, el cual toma los datos, los procesa y los almacena, para posteriormente ser leídos en MATLAB y ser graficados y analizados. Este proceso se realizó con la micro central hidráulica ubicada en el taller mecánico de la Universidad de Chile, donde se tomaron distintas mediciones, que al ser analizadas mostraron diferentes condiciones del generador. Una de estas es la posible excentricidad estática del generador, debido a la alta presencia de armónicos que siguen el patrón f_E=[1±((2k-1)/P)] f_s. Otra de las condiciones encontradas, es la alta posibilidad de tener cortocircuitos en las fases A y B, debido a la presencia significativa de las 3ª, 9ª y 15ª armónicas en dichas fases. Además se presenta el diseño de un banco de pruebas, el cual está previsto para disponer de estados de comparación entre un generador en estado sano y en diferentes condiciones de falla. El sistema de adquisición de datos desarrollado presenta un buen desempeño almacenando datos en línea de la corriente de un generador. Con el cual se pueden realizar análisis del espectro de frecuencia, con el fin de encontrar patrones que permitan diferenciar las distintas fallas, puedan ser estas de índole mecánica o eléctrica. Asimismo, se desarrolla un manual para el posterior uso de la herramienta. Como trabajo futuro se propone integrar un sistema de detección de fallas, el cual pueda identificar en línea las diferentes condiciones que pongan en riesgo la operación de un generador.
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Auyang, Arick Gin-Yu. "Robustness and hierarchical control of performance variables through coordination during human locomotion." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/42837.
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The kinematic motor redundancy of the human legs provides more local degrees of freedom than are necessary to achieve low degree of freedom performance variables like leg length and orientation. The purpose of this dissertation is to investigate how the neuromuscular skeletal system simplifies control of a kinematically redundant system to achieve stable locomotion under different conditions. I propose that the neuromuscular skeletal system minimizes step to step variance of leg length and orientation while allowing segment angles to vary within the set of acceptable combinations of angles that achieves the desired leg length and orientation. I find that during human hopping, control of the locomotor system is organized hierarchically such that leg length and orientation are achieved by structuring segment angle variance. I also found that leg length and leg orientation was minimized for a variety of conditions and perturbations, including frequency, constrained foot placement, and different speeds. The results of this study will give valuable information on interjoint compensation strategies used when the locomotor system is perturbed. This work also provides evidence for neuromuscular system strategies in adapting to novel, difficult tasks. This information can be extended to give insight into new and different areas to focus on during gait rehabilitation of humans suffering from motor control deficits in movement and gait.
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Asakura, Koichi, Toyohide Watanabe, and Noboru Sugie. "An execution order control method of distributed processes for sharing global variables." IEEE, 1994. http://hdl.handle.net/2237/6927.
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Andary, Sally. "The relationship of locus of control and organisational variables to employee outcomes /." Adelaide, 1998. http://web4.library.adelaide.edu.au/theses/09ARPS/09arpsa5431.pdf.
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Wood, Krista E. "Evolution of Scientific Reasoning in Control of Variables for Undergraduate Physics Lab." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1447071195.
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Silva, Luciano Afonso. "Internal Variable and Temperature Modeling Behavior of Viscoelastic Structures -- A Control Analysis." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/28788.
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Most of the methodologies dealing with viscoelastic damping focused exclusively on the frequency dependence behavior of the material. Only a few looked into the temperature dependence of the model, although none of them has taken a more serious investigation on the control design subjected to temperature disturbances. The general purpose of this work is to develop and investigate structures with damping modeled by means of internal variables. Thermodynamic principles are used to develop models, which are based on a generalized Maxwell element. Initially, studies are conducted to verify how the method of reduced variables can be applied to account for temperature dependence, as well as to evaluate the number of internal variables necessary for good accuracy of material properties representation. Lumped and finite element models are characterized and validated against other methods. A constrained layer damping model is experimentally validated for many temperatures. A control analysis is carried out on the models with the purpose to identify the role played by the internal variables on the control design. The results show that moving the internal poles is very expensive in terms of control energy. It is also shown that it is not always possible to eliminate the internal coordinates in the reduced order model if the system is highly damped. The problem of having the internal pole moved is solved by applying partial pole placement. This technique shows similar performance as compared to the linear quadratic Gaussian regulator. The control designs are implemented and it is shown that good regulation can be achieved for a fixed temperature. It is further shown that the controller will lose its performance when the model is subjected to temperature changes. To investigate the behavior of the model under different temperatures, a linear temperature-dependent model is developed, which clearly shows how the temperature affects the time response of the model. This model is used as a baseline to develop an adaptive and a time-varying controllers. With the aid of the shift factor, the eigenvalue variation with temperature is used as a time-varying function in the design. The results show that good track performance and regulation can be achieved with a control law that is capable of compensating for temperature variations.Ph. D.
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Boskov, Lazar. "One-sided screening procedure using multiple normally distributed variables." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-06302009-040451/.
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Lehman, Jeffrey S. "Sequential Design of Computer Experiments for Robust Parameter Design." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1027963706.
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Orozco, Becerra Jose Enrique. "Variables psicológicas predictoras del éxito profesional en microempresarios de Lima Metropolitana." Bachelor's thesis, Pontificia Universidad Católica del Perú, 2018. http://tesis.pucp.edu.pe/repositorio/handle/123456789/13524.
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Perú es considerado uno de los países más emprendedores del mundo. El centro del
emprendimiento son los emprendedores. El objetivo de esta investigación es establecer la
relación que existe entre las variables psicológicas relacionadas al emprendimiento y la
percepción de éxito en sus emprendimientos, es decir el éxito profesional. Los participantes de
este estudio son microempresarios de Lima Metropolitana. Los resultados muestran que solo el
Locus de Control Interno tiene una relación significativa y positiva con la percepción de éxito en
los negocios. Esto podría deberse a la atribución de que uno es responsable de sus propias
acciones. Se discute la necesidad de realizar un estudio a nivel exploratorio para conocer las
actitudes y motivaciones que se relacionan con la percepción de desempeño de los negocios de
los emprendedores peruanos.Peru is considered one of the most entrepreneurial countries of the world. The center of the entrepreneurship activity is the entrepreneur. The purpose of this research is to establish the relationship between psychological variables related to entrepreneurship and the perception of the entrepreneurial success, which is the career success. The participants of this study were microentrepreneurs from Lima Metropolitana. The results show that only Internal Locus of Control has a significant and positive relation with perceived entrepreneurial success. This could be due to the attribution that one is responsible for one's own actions Future research should be directed towards an exploratory level in order to determine the attitudes and motivations that relate with perception of business success of Peruvian entrepreneurs.
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Lilly, Mary Kristine M. S. "An Analysis of Adherence in Childhood Diabetes: Social Learning and Family Systems Variables." Diss., Virginia Tech, 1998. http://hdl.handle.net/10919/30416.
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The purpose of the current study was threefold: 1) to assess youths' and parents' perceptions of their competency in managing diabetes, 2) to assess family flexibility and cohesiveness, and 3) to assess the utility of self-efficacy and family factors as predictors of adherence and metabolic control. Participants included 62 youths with insulin-dependent diabetes mellitus (IDDM) and their parents. Parents' and youths' perceptions of their abilities in diabetes and related situations, family cohesion and adaptability, and perceptions of the family's ability to integrate the demands of the diabetes regimen into general family routines were assessed. Results suggested that both social learning factors and general family relations were important in the prediction of youths' adherence to the treatment regimen for diabetes and metabolic control. Moreover, family efficacy and family cohesion were related, suggesting the need for models of assessment and intervention that include both social learning and general family functioning variables.Ph. D.
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Mills, Timothy Ian Pandachuck. "Speech motor control variables in the production of voicing contrasts and emphatic accent." Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/5815.
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This dissertation looks at motor control in speech production. Two specific questions emerging from the speech motor control literature are studied: the question of articulatory versus acoustic motor control targets, and the question of whether prosodic linguistic variables are controlled in the same way as segmental linguistic variables. In the first study, I test the utility of whispered speech as a tool for addressing the question of articulatory or acoustic motor control targets. Research has been done probing both sides of this question. The case for articulatory specifications is developed in depth in the Articulatory Phonology framework of Haskins researchers (eg. Browman & Goldstein 2000), based on the task-dynamic model of control presented by Saltzman & Kelso (1987). The case for acoustic specifications is developed in the work of Perkell and others (eg Perkell, Matthies, Svirsky & Jordan 1993, Guenther, Espy-Wilson, Boyce, Matthies, Zandipour & Perkell 1999, Perkell, Guenther, Lane, Matthies, Perrier, Vick,Wilhelms-Tricarico & Zandipour 2000). It has also been suggested that some productions are governed by articulatory targets while others are governed by acoustic targets (Ladefoged 2005). This study involves two experiments. In the first, I make endoscopic video recordings of the larynx during the production of phonological voicing contrasts in normal and whispered speech. I discovered that the glottal aperture differences between voiced obstruents (ie, /d) and voiceless obstruents (ie, /t) in normal speech was preserved in whispered speech. Of particular interest was the observation that phonologically voiced obstruents tended to exhibit a narrower glottal aperture in whisper than vowels, which are also phonologically voiced. This suggests that the motor control targets of voicing is different for vowels than for voiced obstruents. A perceptual experiment on the speech material elicited in the endoscopic recordings elicited judgements to see whether listeners could discriminate phonological voicing in whisper, in the absence of non-laryngeal cues such as duration. I found that perceptual discrimination in whisper, while lower than that for normal speech, was significantly above chance. Together, the perceptual and the production data suggest that whispered speech removes neither the acoustic nor the articulatory distinction between phonologically voiced and voiceless segments. Whisper is therefore not a useful tool for probing the question of articulatory versus acoustic motor control targets. In the second study, I look at the multiple parameters contributing to relative prominence, to see whether they are controlled in a qualitatively similar way to the parameters observed in bite block studies to contribute to labial closure or vowel height. I vary prominence by eliciting nuclear accents with a contrastive and a non-contrastive reading. Prominence in this manipulation is found to be signalled by f0 peak, accented syllable duration, and peak amplitude, but not by vowel de-centralization or spectral tilt. I manipulate the contribution of f0 in two ways. The first is by eliciting the contrastive and non-contrastive readings in questions rather than statements. This reduces the f0 difference between the two readings. The second is by eliciting the contrastive and non-contrastive readings in whispered speech, thus removing the acoustic f0 information entirely. In the first manipulation, I find that the contributions of both duration and amplitude to signalling contrast are reduced in parallel with the f0 contribution. This is a qualitatively different behaviour from all other motor control studies; generally, when one variable is manipulated, others either act to compensate or do not react at all. It would seem, then, that this prosodic variable is controlled in a different manner from other speech motor targets that have been examined. In the whisper manipulation, I find no response in duration or amplitude to the manipulation of f0. This result suggests that, like in the endoscopy study, perhaps whisper is not an effective means of perturbing laryngeal articulations.
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Brender, Zoldan Andrés Yonathan. "Proyección de Tasa de Default para Instituciones Bancarias con Variables Macroeconómicas." Tesis, Universidad de Chile, 2010. http://www.repositorio.uchile.cl/handle/2250/103925.
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El objetivo de este trabajo es entregar una estimación de tasas de incumplimiento en carteras de personas naturales (consumo y vivienda) y empresas (comercial) bancos locales. Para ello, se desarrolla una metodología diferente a las tradicionales, que sólo ocupan variables de perfil del cliente (demográficas, comportamiento histórico de pagos, entre otras) sin considerar explícitamente el comportamiento del ciclo económico. Específicamente, se construyen dos modelos estadísticos, uno lineal (mínimos cuadrados ordinarios, o MCO) en conjunto con el modelo de Holt para estimación de series de tiempo que se incorpora como una variable adicional a la regresión, y otro no lineal (redes neuronales), con información de tasas de incumplimiento de los cuatro bancos y variables macroeconómicas entre noviembre de 2004 y noviembre de 2009.
Actualmente, las instituciones bancarias utilizan métodos de estimación por cliente de la proporción (de las colocaciones) que pasan a cartera vencida, de acuerdo a los requerimientos de gestión de riesgo de crédito establecidos en la normativa SBIF. La importancia de una correcta proyección radica en que el banco pueda prever descalces entre lo estimado y lo real, y su impacto en la cartera.
Los resultados obtenidos con ambos métodos en general son satisfactorios. En efecto, en la mayoría de las carteras de los cuatro bancos estudiados, el error relativo entre la tasa estimada y la observada es inferior al rango del 12-20%, que es el error de estimación aceptado, de acuerdo a fuentes provenientes de Gerencias de Riesgo de diversas instituciones bancarias. Por lo tanto, es posible afirmar que con la metodología propuesta se obtiene un nivel de predicción menor a credit scoring usadas por los bancos y las variables macroeconómicas contienen información potencialmente valiosa para predecir incumplimiento. El modelo lineal presenta un menor error relativo en comparación a las redes neuronales, y en particular resulta bastante útil para la estimación del sistema bancario utilizado como referencia para las comparaciones (benchmark).
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Fihla, Priscilla Mandlakazi. "Relationships among Law School Experience and Selected Personality and cognitive Style Variables." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1392220414.
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Sipos, James Martin. "The relationship of the power motive and certain demographic variables to brokerage firm salespersons's sales success /." The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487329662147396.
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Zhang, Xi. "Physical and statistical analysis of functional process variables for process control in semiconductor manufacturing." [Tampa, Fla] : University of South Florida, 2009. http://purl.fcla.edu/usf/dc/et/SFE0003176.
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Jaeckle, Christiane M. "Product and process improvement using latent variable methods." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0006/NQ42853.pdf.
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Kuhn, Rachel. "Health Locus of Control in HIV: Healthy Individuals with Low CD4 Cells versus an HIV-positive Comparison Group." Scholarly Repository, 2008. http://scholarlyrepository.miami.edu/oa_theses/96.
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Research examining multidimensional health locus of control (MHLOC) beliefs in HIV-positive individuals is limited. While studies in numerous other medical populations have shown relationships between MHLOC and markers of protected health status, no other studies, to our knowledge, have done so in HIV. The MHLOC has four subscales: Internal, Chance, Doctors, and Other People. Each subscale measures the degree of belief that one's health is controlled by one of these four constructs. This study compared the MHLOC beliefs of a rare group of healthy HIV-positive individuals with very low CD4 cell counts (below 50) who were not taking HAART (HLC group), to a group of HIV-positive individuals in the mid-range of disease progression (matched control (MC) group). Two hundred forty-seven diverse participants with HIV completed MHLOC scales as part of a psychosocial battery. Seventy participants from a larger "control" group (N = 177) were matched one-to-one with a participant from the HLC group (N = 70) on four demographic variables (gender, education, ethnicity, and income). The HLC group was found to have significantly lower Internal control beliefs and higher Doctor beliefs in comparison to the MC group. An examination of MHLOC beliefs within each group showed that for both groups, Doctor beliefs were strongest, followed by Internal, Chance and Other People beliefs. Compared to the MC group, individuals with protected health status (HLC group) were more likely to have a combination of "high" Doctor and "low" Internal beliefs and less likely to have a combination of "low" Doctor and "high" Internal beliefs. Finally, affective depression approached significance as a mediator in the relationship between Doctor control beliefs and group status (HLC vs. MC group). Specifically, protected health status was related to higher Doctor beliefs and lower affective depression. Study limitations and implications are discussed.
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Gilmore, Geoffrey Paul. "Identifying Quality Function Deployment's Variables, Outcomes, Their Relationships, and Guidelines for Practitioners in the American Automotive Industry." PDXScholar, 1992. https://pdxscholar.library.pdx.edu/open_access_etds/1157.
Full textAbstract:
American industry is about nine to 12 years behind in utilizing a new product development and introduction process known as Quality Function Deployment (Q.F.D.). American industry must learn to compete internationally; the American automotive industry alone directly and indirectly employs millions of workers and has billions of dollars in annual sales and profits at stake. With the cooperation of one American automotive company research has been conducted on Q.F.D. The research objectives were to identify: what variables affect Q.F.D., what are the outcomes from Q.F.D., what relationships exist between Q.F.D. variables and outcomes, and what guidelines may be offered to Q.F.D. practitioners. A Multiple Perspectives systems approach was used in developing both what and how Q.F.D. was to be researched. After a literature search a descriptive Q.F.D. model was developed. A Q.F.D. measurement instrument was developed and used to collect technical data. Interviews were used to collect organizational and personal data. An 80% questionnaire response was obtained. Of the model's four outcomes Improved Design and Improved Communications had strong positive results with Improved Cost and Improved Time-to-Market unchanged. Explanations of these results were offered. A Factor Analysis was performed which verified that the three-level Q.F.D. model was appropriate and explained most of the response variation. A Reliability Assessment was conducted and the scales were found to be within or have exceeded the acceptable beginning research coefficient alpha range. A MANOVA Analysis was conducted, and five of the 17 Q.F.D. model's variables were identified as candidates for deletion for this company's present Q.F.D. system. A Ratio Data Assessment was conducted and used to develop five guidelines for this company's practitioners. Organizational and Personal Data Assessments were conducted and their similarities with the Technical Data Assessment were noted. Top Management Commitment, Customer Information Availability, Team Composition and Dynamics and Project Completion Time were identified as important similar Q.F.D. variable findings. Improved Design and Improved Communications were identified as important similar Q.F.D. outcomes. No major discontinuities between the three assessments were found. Research conclusions, contributions and future research work were identified.
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McGlone, John Francis. "Analyzing Tuberculosis Vulnerability and Variables in Tarrant County." Thesis, University of North Texas, 2016. https://digital.library.unt.edu/ark:/67531/metadc955077/.
Full textAbstract:
Over 9 million new cases of tuberculosis (TB) were reported worldwide in 2013. While the TB rate is much lower in the US, its uneven distribution and associated explanatory variables require interrogation in order to determine effective strategies for intervention and control. However, paucity of case data at fine geographic scales precludes such research. This research, using zip code level data from 837 confirmed TB cases in Tarrant County obtained from Texas Department of State Health Services, explores and attempts to explain the spatial patterns of TB and related risk markers within a framework of place vulnerability. Readily available census data is then used to characterize the spatial variations in TB risk. The resulting model will enable estimations of the geographic differences in TB case variables using this readily available census data instead of time-consuming and expensive individual data collection.
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Handsel, Vanessa A. "Psychological variables in battered women's stay/leave decisions : risk-taking perceived control, and optimistic bias /." Electronic version (PDF), 2007. http://dl.uncw.edu/etd/2007-1/handselv/vanessahandsel.pdf.
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Höfler, Michael, Tanja Brueck, Roselind Lieb, and Hans-Ulrich Wittchen. "Calculating control variables with age at onset data to adjust for conditions prior to exposure." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-105363.
Full textAbstract:
Background: When assessing the association between a factor X and a subsequent outcome Y in observational studies, the question that arises is what are the variables to adjust for to reduce bias due to confounding for causal inference on the effect of X on Y. Disregarding such factors is often a source of overestimation because these variables may affect both X and Y. On the other hand, adjustment for such variables can also be a source of underestimation because such variables may be the causal consequence of X and part of the mechanism that leads from X to Y.
Methods: In this paper, we present a simple method to compute control variables in the presence of age at onset data on both X and a set of other variables. Using these age at onset data, control variables are computed that adjust only for conditions that occur prior to X. This strategy can be used in prospective as well as in survival analysis. Our method is motivated by an argument based on the counterfactual model of a causal effect.
Results: The procedure is exemplified by examining of the relation between panic attack and the subsequent incidence of MDD.
Conclusions: The results reveal that the adjustment for all other variables, irrespective of their temporal relation to X, can yield a false negative result (despite unconsidered confounders and other sources of bias).
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Höfler, Michael, Tanja Brueck, Roselind Lieb, and Hans-Ulrich Wittchen. "Calculating control variables with age at onset data to adjust for conditions prior to exposure." Technische Universität Dresden, 2005. https://tud.qucosa.de/id/qucosa%3A26586.
Full textAbstract:
Background: When assessing the association between a factor X and a subsequent outcome Y in observational studies, the question that arises is what are the variables to adjust for to reduce bias due to confounding for causal inference on the effect of X on Y. Disregarding such factors is often a source of overestimation because these variables may affect both X and Y. On the other hand, adjustment for such variables can also be a source of underestimation because such variables may be the causal consequence of X and part of the mechanism that leads from X to Y.
Methods: In this paper, we present a simple method to compute control variables in the presence of age at onset data on both X and a set of other variables. Using these age at onset data, control variables are computed that adjust only for conditions that occur prior to X. This strategy can be used in prospective as well as in survival analysis. Our method is motivated by an argument based on the counterfactual model of a causal effect.
Results: The procedure is exemplified by examining of the relation between panic attack and the subsequent incidence of MDD.
Conclusions: The results reveal that the adjustment for all other variables, irrespective of their temporal relation to X, can yield a false negative result (despite unconsidered confounders and other sources of bias).
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Laurí, Pla David. "MPC: Relevant Identification and Control in the Latent Variable Space." Doctoral thesis, Universitat Politècnica de València, 2012. http://hdl.handle.net/10251/15178.
Full textAbstract:
Control predictivo basado en modelos (MPC) es una metodología de control ampliamente utilizada en la industria por su habilidad para controlar procesos multivariable con restricciones en sus entradas y sus salidas. Se distinguen dos fases en la implementación de MPC: identificación y control. El propósito de esta tesis es doble: realizar contribuciones en la identificación para MPC y proponer una nueva metodología de control MPC.
La respuesta en bucle cerrado de una implementación de MPC depende, en gran medida, de la capacidad de predicción del modelo; luego la identificación del modelo es un punto crucial en MPC y la parte que a menudo exige la mayor parte del tiempo del proyecto. El primer objetivo que cubre la tesis es la identificación para MPC. Puesto que un modelo es una aproximación del comportamiento de un proceso, dicha aproximación se puede hacer teniendo en cuenta el fin que se le va a dar al modelo. En MPC, el modelo se utiliza para realizar predicciones dentro de una ventana futura, luego la identificación para MPC (MRI) tiene en cuenta dicho uso del modelo y considera los errores de predicción dentro de dicha ventana para el ajuste de los parámetros del modelo. En esta tesis, se cubren tres temas dentro de MRI. Primero se define MRI y las distintas formas de abordarlo. Luego se compara en términos de MRI el ajuste de un modelo con múltiples entradas y múltiples salidas con el ajuste de varios modelos con múltiples entradas y una salida concluyendo que el ajuste de un único modelo con múltiples entradas y múltiples salidas proporciona mejores resultados en términos de MRI para horizontes de predicción lo suficientemente grandes. Por último, se propone el algoritmo PLS-PH para implementar MRI con modelos paramétricos en el caso de correlación en los datos de identificación. PLS-PH es un método de optimización numérica por búsqueda lineal basado en PLS (mínimos cuadrados parciales). Se muestra en un ejemplo como PLS-PH es capaz de proporcionar mejores modelos que
las técnicas convencionales de MRI en modelos paramétricos en el caso de
correlación en los datos de identi ficación.
Una vez obtenido el modelo se puede formular el controlador predictivo.
En esta tesis se propone LV-MPC, un controlador predictivo para procesos
continuos que implementa la optimización en el espacio de las componentes
principales.Laurí Pla, D. (2012). MPC: Relevant Identification and Control in the Latent Variable Space [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/15178
Palancia
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Sadi, Ozlem. "Relation Of Cognitive And Motivational Variables With Students." Phd thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/2/12611727/index.pdf.
Full textAbstract:
This study aimed to investigate the relationships among high school students&rsquorelevant prior knowledge, meaningful learning orientation, reasoning ability, self-efficacy, locus of control, attitudes toward biology and achievement in human circulatory system in learning cycle and traditional classrooms. This study was conducted with 2 teachers and 4 classes and total of 60 11th grade students in the private high schools at Ü
mitkö
y district of Ankara in the fall semester of 2008-2009 academic years. One class of each teacher was assigned as experimental group and treated with 5E learning cycle instruction and other class was assigned as control group and treated with traditional instruction. At the beginning of the study, both teachers were trained for how to implement 5E learning cycle instruction in the classrooms. The Human Circulatory System Achievement Test was applied twice as pre-test and after treatment period as a post-test to both experimental and control groups. Learning Approach Questionnaire was used to measure students&rsquo
approach to learning and Test of Logical Thinking was used to measure reasoning abilitiy of students. Students&rsquo
levels of self-efficacy, locus of control and their attitudes toward biology also were measured. The data obtained from the administration of post-test were analyzed by using ANOVA. The statistical result indicates that learning cycle instruction improved students&rsquo
achievement in human circulatory system compared to traditional instruction. Stepwise multiple regression analysis revealed that in learning cycle classrooms, the main predictors of achievement in human circulatory system were students&rsquo
reasoning ability (45.8%) and their prior knowledge (15.9%). In traditional classrooms, students&rsquo
meaningful learning orientation (40%) and locus of control (9.8%) were the main predictors of achievement. This study indicated that different variables may be significant for 11th grade students&rsquo
human circulatory system achievement in learning cycle and traditional classes.
46
Fuente, Flores David Marcial. "Desarrollo de herramientas de control para mejorar los niveles de recaudación de los ingresos propios en el HNRPP EsSalud-2017." Bachelor's thesis, Universidad Continental, 2018. http://repositorio.continental.edu.pe/handle/continental/4938.
Full textAbstract:
La presente tesis brinda información sobre errores que se cometen comúnmente en la gestión de la recaudación de los Ingresos en la Seguridad Social al no dar la debida importancia a las herramientas de control interno para mantener adecuadamente los niveles de recaudación, esto servirá para poder tener un conocimiento más adecuado en áreas específicas que permitirán incrementar los niveles de recaudación de los ingresos del Hospital Nacional Ramiro Prialé Prialé, reflejando una mejor gestión financiera y presupuestal, siendo los beneficiados directos, los asegurados y usuarios en general. Es por ello que surge la necesidad de desarrollar las herramientas de control interno que permitirán mejorar la gestión de recaudación de los Ingresos Propios en el HNRPP – Essalud – 2017. Los aspectos de investigación considerados fueron el diseño de investigación no experimental transeccional correlacional y la técnica de recolección de datos por medio de encuestas y como instrumento el cuestionario elaborado con 22 preguntas, tomando como muestra y objeto de estudio de esta investigación a los jefes y colaboradores de la División de Finanzas, Unidad de Tesorería y Presupuesto y el Área de Ingresos y Facturación del HNRPP. Posteriormente la información obtenida fue tabulada, procesada y analizada con el software SPSS. Versión 22. Así mismo se ha identificado como Variable Independiente: Herramientas de Control, Variable Dependiente: Niveles de recaudación de los ingresos. Los resultados obtenidos de este estudio permitirán mejorar las deficiencias de la Gestión de Recaudación de Ingresos Propios en el HNRPP- EsSalud-2017, considerando dentro de los componentes de control a la elaboración de un diseño de diagramas de flujo de los procesos y control estadístico de actividades de las áreas antes señaladas. Finalmente se confirma que las herramientas de Control Interno permiten mejorar el flujo de actividades optimizando el sistema y superando las deficiencias de la gestión de recaudación de los ingresos propios. Este trabajo es un aporte al Hospital Nacional Ramiro Prialé Prialé al dar a conocer la importancia que tiene el desarrollo del sistema de control interno como una herramienta importante para mejorar los niveles de recaudación en el área de ingresos y facturación, soporte importante dentro de la institución que se reflejará en el mejor servicio y atención no solo a la población asegurada, sino también a la colectividad de la región en general.
47
Fen, Yun-Jr. "The design of a microcomputer based true basic statistical process control package for inspection by variables." Ohio University / OhioLINK, 1989. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1182435780.
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Beermann, Dennis [Verfasser]. "POD-based scalar and multiobjective optimal control of evolution equations including operator-valued variables / Dennis Beermann." Konstanz : KOPS Universität Konstanz, 2019. http://d-nb.info/1191099636/34.
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Ames, Ramírez Juan Carlos. "Control de variables en el espesador de cono profundo en la recuperación de relaves altamente fluibles." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2012. https://hdl.handle.net/20.500.12672/16231.
Full textAbstract:
Publicación a texto completo no autorizada por el autorDetermina la estructura de flóculo adecuada que permita la máxima claridad del líquido y máxima densidades en la descarga con el mínimo de dosificación que permita seleccionar las condiciones de alimentación para la operación del espesador piloto. Determinadas las condiciones de alimentación sigue una serie de ratios de tratamiento para determinar la máxima carga posible bajo condiciones óptimas de floculación en términos de TPD/m2. Durante estas series, se mantiene constante el nivel de sólidos y se monitorea la densidad del underflow manteniendo el balance alimentación descarga. La serie final de pruebas enfoca la maximización de la densidad en el underflow con diferentes tiempos de retención. Varios niveles de tratamiento y de altura de sólidos son mantenidos para determinar el requerimiento del tiempo de residencia de los sólidos y ratios de ascensión del overflow para un diseño industrial. El máximo ratio de tratamiento (TPD/m2), ratios de ascensión (m/h) y tiempo de retención, a una determinada densidad promedio, son usados para seleccionar el diámetro y la altura de las paredes del espesador. Muestras del rebose, descarga y alimentación fueron tomadas con la mayor frecuencia posible para determinar cualquier variación en las características de la alimentación que puedan afectar la floculación y en consecuencia la claridad del rebose y espesamiento. Típicamente, cambios en la distribución granulométrica, tipo de mineral, y pH tienen un gran impacto. Fue importante identificar las variaciones en las características de la alimentación que tienen efecto en la performance del espesador para asegurar una claridad en el rebose y densidad en la descarga del espesador compatibles con los requerimientos del proceso.
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Vidal, Puig Santiago. "FAULT DIAGNOSIS TOOLS IN MULTIVARIATE STATISTICAL PROCESS AND QUALITY CONTROL." Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/61292.
Full textAbstract:
[EN] An accurate fault diagnosis of both, faults sensors and real process faults have become more and more important for process monitoring (minimize downtime, increase safety of plant operation and reduce the manufacturing cost). Quick and correct fault diagnosis is required in order to put back on track our processes or products before safety or quality can be compromised. In the study and comparison of the fault diagnosis methodologies, this thesis distinguishes between two different scenarios, methods for multivariate statistical quality control (MSQC) and methods for latent-based multivariate statistical process control: (Lb-MSPC). In the first part of the thesis the state of the art on fault diagnosis and identification (FDI) is introduced. The second part of the thesis is devoted to the fault diagnosis in multivariate statistical quality control (MSQC). The rationale of the most extended methods for fault diagnosis in supervised scenarios, the requirements for their implementation, their strong points and their drawbacks and relationships are discussed. The performance of the methods is compared using different performance indices in two different process data sets and simulations. New variants and methods to improve the diagnosis performance in MSQC are also proposed. The third part of the thesis is devoted to the fault diagnosis in latent-based multivariate statistical process control (Lb-MSPC). The rationale of the most extended methods for fault diagnosis in supervised Lb-MSPC is described and one of our proposals, the Fingerprints contribution plots (FCP) is introduced. Finally the thesis presents and compare the performance results of these diagnosis methods in Lb-MSPC. The diagnosis results in two process data sets are compared using a new strategy based in the use of the overall sensitivity and specificity[ES] La realización de un diagnóstico preciso de los fallos, tanto si se trata de fallos de sensores como si se trata de fallos de procesos, ha llegado a ser algo de vital importancia en la monitorización de procesos (reduce las paradas de planta, incrementa la seguridad de la operación en planta y reduce los costes de producción). Se requieren diagnósticos rápidos y correctos si se quiere poder recuperar los procesos o productos antes de que la seguridad o la calidad de los mismos se pueda ver comprometida. En el estudio de las diferentes metodologías para el diagnóstico de fallos esta tesis distingue dos escenarios diferentes, métodos para el control de estadístico multivariante de la calidad (MSQC) y métodos para el control estadístico de procesos basados en el uso de variables latentes (Lb-MSPC). En la primera parte de esta tesis se introduce el estado del arte sobre el diagnóstico e identificación de fallos (FDI). La segunda parte de la tesis está centrada en el estudio del diagnóstico de fallos en control estadístico multivariante de la calidad. Se describen los fundamentos de los métodos más extendidos para el diagnóstico en escenarios supervisados, sus requerimientos para su implementación sus puntos fuertes y débiles y sus posibles relaciones. Los resultados de diagnóstico de los métodos es comparado usando diferentes índices sobre los datos procedentes de dos procesos reales y de diferentes simulaciones. En la tesis se proponen nuevas variantes que tratan de mejorar los resultados obtenidos en MSQC. La tercera parte de la tesis está dedicada al diagnóstico de fallos en control estadístico multivariante de procesos basados en el uso de modelos de variables latentes (Lb-MSPC). Se describe los fundamentos de los métodos mas extendidos en el diagnóstico de fallos en Lb-MSPC supervisado y se introduce una de nuestras propuestas, el fingerprint contribution plot (FCP). Finalmente la tesis presenta y compara los resultados de diagnóstico de los métodos propuestos en Lb-MSPC. Los resultados son comparados sobre los datos de dos procesos usando una nueva estrategia basada en el uso de la sensitividad y especificidad promedia.
[CAT] La realització d'un diagnòstic precís de les fallades, tant si es tracta de fallades de sensors com si es tracta de fallades de processos, ha arribat a ser de vital importància en la monitorització de processos (reduïx les parades de planta, incrementa la seguretat de l'operació en planta i reduïx els costos de producció) . Es requerixen diagnòstics ràpids i correctes si es vol poder recuperar els processos o productes abans de que la seguretat o la qualitat dels mateixos es puga veure compromesa. En l'estudi de les diferents metodologies per al diagnòstic de fallades esta tesi distingix dos escenaris diferents, mètodes per al control estadístic multivariant de la qualitat (MSQC) i l mètodes per al control estadístic de processos basats en l'ús de variables latents (Lb-MSPC). En la primera part d'esta tesi s'introduïx l'estat de l'art sobre el diagnòstic i identificació de fallades (FDI). La segona part de la tesi està centrada en l'estudi del diagnòstic de fallades en control estadístic multivariant de la qualitat. Es descriuen els fonaments dels mètodes més estesos per al diagnòstic en escenaris supervisats, els seus requeriments per a la seua implementació els seus punts forts i febles i les seues possibles relacions. Els resultats de diagnòstic dels mètodes és comparat utilitzant diferents índexs sobre les dades procedents de dos processos reals i de diferents simulacions. En la tesi es proposen noves variants que tracten de millorar els resultats obtinguts en MSQC. La tercera part de la tesi està dedicada al diagnòstic de fallades en control estadístic multivariant de processos basat en l'ús de models de variables latents (Lb-MSPC). Es descriu els fonaments dels mètodes més estesos en el diagnòstic de fallades en MSPC supervisat i s'introdueix una nova proposta, el fingerprint contribution plot (FCP). Finalment la tesi presenta i compara els resultats de diagnòstic dels mètodes proposats en MSPC. Els resultats són comparats sobre les dades de dos processos utilitzant una nova estratègia basada en l'ús de la sensibilitat i especificitat mitjana.
Vidal Puig, S. (2016). FAULT DIAGNOSIS TOOLS IN MULTIVARIATE STATISTICAL PROCESS AND QUALITY CONTROL [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/61292
TESIS