Mit Hilfe der Technik des Automatischen Differenzierens (AD) lassen sich für Funktionen, die als Programmquellcode gegeben sind, Ableitungsinformationen rechentechnisch effizient und mit geringem Aufwand für den Nutzer bereitstellen. Eine Variante der Implementierung von AD basiert auf der Überladung von Operatoren und Funktionen, die von vielen modernen Programmiersprachen ermöglicht wird. Durch Ausnutzung des Konzepts der Überladung wird eine interne Funktions-Repräsentation (Tape) generiert, die anschließend für die Ableitungsberechnung herangezogen wird. In der Dissertation werden neue Techniken erarbeitet, die eine effizientere Tape-Erstellung und die parallele Tape-Auswertung ermöglichen. Anhand von Laufzeituntersuchungen für numerische Beispiele werden die Möglichkeiten der neuen Techniken verdeutlicht. / Using the technique of Automatic Differentiation (AD), derivative information can be computed efficiently for any function that is given as source code in a supported programming languages. One basic implementation strategy is based on the concept of operator overloading that is available for many programming languages. Due the overloading of operators, an internal representation of the function can be generated at runtime. This so-called tape can then be used for computing derivatives. In the thesis, new techniques are introduced that allow a more efficient tape creation and the parallel evaluation of tapes. Advantages of the new techniques are demonstrated by means of runtime analyses for numerical examples.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal

The high costs and political tensions associated with Ballistic Missile Defense Systems (BMDS) has driven much of the testing and evaluation of BMDS to be performed through high fidelity Modeling and Simulation (M&S). In response, the M&S environments have become highly complex, extremely computationally intensive, and far too slow to be of use to systems engineers and high level decision makers. Regression models can be used to map the system characteristics to the metrics of interest, bringing about large quantities of data and allowing for real-time interaction with high-fidelity M&S environments, however the abundance of discontinuities and non-unique solutions makes the application of regression techniques hazardous. Due to these ambiguities, the transfer function from the characteristics to the metrics appears to have multiple solutions for a given set of inputs, which combined with the multiple inputs yielding the same set of outputs, causes troubles in creating a mapping. Due to the abundance of discontinuities, the existence of a neural network mapping from the system attributes to the performance metrics is not guaranteed, and if the mapping does exist, it requires a large amount of data to be for creating a regression model, making regression techniques less suitable to BMDS analysis. By employing Nested Neural Networks (NNNs), intermediate data can be associated with an ambiguous output which can allow for a regression model to be made. The addition of intermediate data incorporates more knowledge of the design space into the analysis. Nested neural networks divide the design space to form a piece-wise continuous function, which allows for the user to incorporate system knowledge into the surrogate modeling process while reducing the size of a data set required to form the regression model. This thesis defines nested neural networks along with methods and techniques for using NNNs to relieve the effects of discontinuities and non-unique solutions. To show the benefit of the approach, these techniques are applies them to a BMDS simulation. Case studies are performed to optimize the system configurations and assess robustness which could not be done without the regression models.

O vírus da imunodeficiência felina (FIV) é um membro da subfamília Lentivirinae da família Retroviridae. A infecção é caracterizada por imunodepressão com um declíneo progressivo dos linfócitos T CD4+, propiciando, desta maneira, o surgimento de infecções oportunistas. Já o vírus da leucemia viral felina (FeLV) pertence a subfamília Oncovirinae da família Retroviridae. Este vírus é um importante patógeno dos gatos domésticos que causa uma variedade de desordens neoplásicas e degenerativas e também apresenta distribuição mundial. O presente estudo compreendeu um levantamento da prevalência das infecções por FIV e FeLV no Município de Porto Alegre. Foram analisadas 65 amostras de gatos sadios e doentes. A detecção destas viroses foi realizada utilizando um “kit” comercial de ELISA para ambas as viroses e um protocolo de reação em cadeia da polimerase aninhada (Nested-PCR) para detecção do FIV. Os resultados demonstraram que 21,5% (14/65) dos gatos foram positivos para FIV combinado os resultados de ambos os testes, 10,8% (7/65) foram positivos para FeLV e 6,1% (4/65) foram positivos para ambos os vírus. Foram também realizados hemogramas de 48 animais, dos quais 8 apresentaram resultados positivos para FIV na Nested-PCR. Através do teste T de Student, verificou-se que não houve diferença significativa nos valores hematológicos destes animais. Conclui-se que a utilização do ELISA com a PCR dobrou a chance de detecção de gatos FIV positivos. Desta forma, a prevalência de FIV foi aproximadamente o dobro do que a de FeLV, ao contrário do que ocorre na maior parte de outros locais estudados. / Feline immunodeficiency virus (FIV) belongs to the Lentivirinae subfamily of the Retroviridae family. The infection is characterized by immunodepression and progressive decline in CD4+ T cells that may render the animal susceptible to opportunistic infections. Feline leukemia virus (FeLV) belongs to subfamily Oncovirinae of the Retroviridae family. The virus also affects domestic cats, being an important pathogen that causes a variety of neoplastic disorders and degenerative diseases. Both viruses have a worldwide distribution. The present study aims to determine the prevalence of infection with FIV and FeLV in Porto Alegre municipality. A total of 65 cats were tested, comprising healthy and sick cats. A commercial ELISA kit was used to detect anti-FIV antibodies and FeLV antigen. A nested polymerase chain reaction (Nested-PCR) was also used for FIV provirus detection. The results showed that 21.5% of the sampled cats were positive for FIV in the ELISA and Nested-PCR, 10.8% were positive for FeLV in the ELISA and 6.1% were positive for both viruses. Haemogram of 48 animals were performed but it was not found any significant association between hematologic values of FIV positive and negative animals. It was concluded that the use of ELISA and Nested-PCR increased the possibility to detect FIV positive cats. The prevalence of FIV infected cats was higher than the prevalence of FeLV positive cats, the opposite of what is normally found in studies performed in other regions.

Portfolio Management is the process of allocating an investor's wealth to in­ vestment opportunities over a given planning period. Not only should Portfolio Management be treated within a multi-period framework, but one should also take into consideration the stochastic nature of related parameters. After a short review of key concepts from Finance Theory, e.g. utility function, risk attitude, Value-at-rusk estimation methods, a.nd mean-variance efficiency, this work describes a framework for the formulation of the Portfolio Management problem in a Stochastic Programming setting. Classical solution techniques for the resolution of the resulting Stochastic Programs (e.g. L-shaped Decompo­ sition, Approximation of the probability function) are presented. These are discussed within both the two-stage and the multi-stage case with a special em­ phasis on the former. A description of how Importance Sampling and EVPI are used to improve the efficiency of classical methods is presented. Postoptimality Analysis, a sensitivity analysis method, is also described. / Statistics / M. Sc. (Operations Research)

O vírus da imunodeficiência felina (FIV) é um membro da subfamília Lentivirinae da família Retroviridae. A infecção é caracterizada por imunodepressão com um declíneo progressivo dos linfócitos T CD4+, propiciando, desta maneira, o surgimento de infecções oportunistas. Já o vírus da leucemia viral felina (FeLV) pertence a subfamília Oncovirinae da família Retroviridae. Este vírus é um importante patógeno dos gatos domésticos que causa uma variedade de desordens neoplásicas e degenerativas e também apresenta distribuição mundial. O presente estudo compreendeu um levantamento da prevalência das infecções por FIV e FeLV no Município de Porto Alegre. Foram analisadas 65 amostras de gatos sadios e doentes. A detecção destas viroses foi realizada utilizando um “kit” comercial de ELISA para ambas as viroses e um protocolo de reação em cadeia da polimerase aninhada (Nested-PCR) para detecção do FIV. Os resultados demonstraram que 21,5% (14/65) dos gatos foram positivos para FIV combinado os resultados de ambos os testes, 10,8% (7/65) foram positivos para FeLV e 6,1% (4/65) foram positivos para ambos os vírus. Foram também realizados hemogramas de 48 animais, dos quais 8 apresentaram resultados positivos para FIV na Nested-PCR. Através do teste T de Student, verificou-se que não houve diferença significativa nos valores hematológicos destes animais. Conclui-se que a utilização do ELISA com a PCR dobrou a chance de detecção de gatos FIV positivos. Desta forma, a prevalência de FIV foi aproximadamente o dobro do que a de FeLV, ao contrário do que ocorre na maior parte de outros locais estudados. / Feline immunodeficiency virus (FIV) belongs to the Lentivirinae subfamily of the Retroviridae family. The infection is characterized by immunodepression and progressive decline in CD4+ T cells that may render the animal susceptible to opportunistic infections. Feline leukemia virus (FeLV) belongs to subfamily Oncovirinae of the Retroviridae family. The virus also affects domestic cats, being an important pathogen that causes a variety of neoplastic disorders and degenerative diseases. Both viruses have a worldwide distribution. The present study aims to determine the prevalence of infection with FIV and FeLV in Porto Alegre municipality. A total of 65 cats were tested, comprising healthy and sick cats. A commercial ELISA kit was used to detect anti-FIV antibodies and FeLV antigen. A nested polymerase chain reaction (Nested-PCR) was also used for FIV provirus detection. The results showed that 21.5% of the sampled cats were positive for FIV in the ELISA and Nested-PCR, 10.8% were positive for FeLV in the ELISA and 6.1% were positive for both viruses. Haemogram of 48 animals were performed but it was not found any significant association between hematologic values of FIV positive and negative animals. It was concluded that the use of ELISA and Nested-PCR increased the possibility to detect FIV positive cats. The prevalence of FIV infected cats was higher than the prevalence of FeLV positive cats, the opposite of what is normally found in studies performed in other regions.

Basic studies of seed germination and seedling emergence assume an important role within scientific researches due to the devastation and fragmentation of the native vegetation of the Cerrado. Thus, in the present study the processes of seed germination and seedling emergency were evaluated using the linear correlations among the measurements calculated for five Cerrado species. The individual contribution for the variability of the studied species and the contribution of each species in relation to the studied group were also quantified. For this purpose, hierarchical lineal models were used to determine the genetic parameters among individuals within the species. The diaspores were collected in the 2004/2005 crops, in a fragmented area of the Araguari river valley, MG. The experiments were carried out using newly-collected diaspores, being conducted in a germination chamber for germination and in a greenhouse covered with light reducing net for seedling emergency. The data collection was carried out every 24 hours, taking into account the protrusion of the embryo for the experiments set up in the laboratory and the emergence of any part of seedling above the substratum for experiments kept in greenhouse. The variability registered among the individuals of the studied species generated statistical differences in all aspects of the germination and emergency processes, indicating that the decision to mix the diaspores or not for the formation of the lots should be made after results of previous tests. High mean values were registered for germinability (G) and emergency percentage (E) for the majority of individuals studied, indicating the good physiological quality of the diaspores produced in the 2004-2005 crop. The seed germination and seedling emergence of Anadenanthera colubrina and Chorisia speciosa and the seedling emergence of Myracrodruon urundeuva were faster and synchronized, while those of Cedrela fissilis and Lithraea molleoides were slower, asynchronous and spread over time, indicating the presence of relative dormancy. These germination and emergence patterns were confirmed by means of positive linear correlations between E and Z (synchrony) and negative between E and U (uncertainty) for the synchronous events; negative correlations between E and Z and positive and E and U for the asynchronous. For C. speciosa the synchrony of germination was also expressed by the positive association between G and v (mean germination rate). The partition of the variability allowed one to verify that the germination process and seedling emergence present a pattern behavior intrinsic to each species, with more than 60% of the total variability attributed to the species. Above 0.80 of the heritability was registered for most of the characteristics evaluated, indicating that the largest proportion of the total variability is of genetic nature. High genetic variability, expressed by the CVg and detected for time, rate, and synchrony measurements was registered between the L. molleoides and C. fissilis individuals. The magnitude of the CVg values showed that genetic variation exists in the studied species in relation to the germination and emergency processes and then they should be included in conservation projects. / Os estudos básicos de germinação de sementes e emergência de plântulas assumem papel relevante dentro das pesquisas científicas diante da realidade de devastação e fragmentação da vegetação nativa do Cerrado. Em função disso, o presente trabalho teve por objetivos avaliar o processo de germinação de diásporos e a emergência de plântulas de cinco espécies do Cerrado do Planalto Central e, a partir de medidas desses processos, quantificar as correlações lineares entre as mesmas; quantificar a contribuição da variabilidade das matrizes para as espécies estudadas e de cada espécie em relação ao grupo estudado, utilizando-se modelos lineares hierárquicos e, estimar parâmetros genéticos entre matrizes dentro de espécies. Os diásporos foram coletados nas safras 2004/2005 numa região fragmentada do vale do rio Araguari, MG. Os testes foram realizados com diásporos recém-coletados de matrizes em separado, sendo os testes de germinação instalados em câmara de germinação e os de emergência em estufa coberta com telado redutor de luminosidade. A coleta dos dados foi realizada a cada 24 horas, observando-se a protrusão do embrião para os experimentos montados em laboratório e a emergência de qualquer parte da plântula acima do substrato para experimentos mantidos em estufa. Registrou-se variabilidade entre as matrizes das espécies estudadas em todos os aspectos do processo de germinação e emergência e, por isso, a decisão da mistura ou não dos diásporos para a formação dos lotes deve ser tomada após a realização de testes prévios. Foram registrados altos valores médios para germinabilidade (G) e porcentagem de emergência (E) para as matrizes estudadas, indicando a boa qualidade fisiológica dos diásporos produzidos na safra 2004-2005. Os processos de germinação de sementes e emergência de plântulas de Anadenanthera colubrina e Chorisia speciosa e de emergência de plântulas de Myracrodruon urundeuva foram mais rápidos e sincronizados, enquanto para Cedrela fissilis e Lithraea molleoides foram mais lentos, assíncronos e espalhados no tempo, indicando a presença de dormência relativa. Esse padrão de comportamento foi confirmado por meio das correlações positivas entre E e Z (sincronia) e negativas entre E e I (incerteza) para os eventos síncronos; correlações negativas entre E e Z e positivas entre E e I para os assíncronos. Para C. speciosa a sincronia da germinação também foi retratada pela associação positiva entre G e v (velocidade média). A partição da variabilidade permitiu verificar que o processo de germinação e emergência de plântulas apresenta padrão de comportamento característico e intrínseco das espécies, com mais de 60% da variabilidade total atribuída às espécies. A herdabilidade da maioria das características avaliadas apresentou valores acima de 0,80, indicando que a maior proporção da variabilidade total é de natureza genética. Alta variabilidade genética, expressa pelo CVg, e detectada para as medidas de tempo, velocidade e sincronia foi registrada entre as matrizes de L. molleoides e C. fissilis. A magnitude dos valores de CVg mostrou que existe variação genética nas espécies estudadas com relação aos processos de germinação e emergência e, por se tratar de material com variabilidade natural, devem ser incluídas em projetos de conservação. / Mestre em Agronomia

O vírus da imunodeficiência felina (FIV) é um membro da subfamília Lentivirinae da família Retroviridae. A infecção é caracterizada por imunodepressão com um declíneo progressivo dos linfócitos T CD4+, propiciando, desta maneira, o surgimento de infecções oportunistas. Já o vírus da leucemia viral felina (FeLV) pertence a subfamília Oncovirinae da família Retroviridae. Este vírus é um importante patógeno dos gatos domésticos que causa uma variedade de desordens neoplásicas e degenerativas e também apresenta distribuição mundial. O presente estudo compreendeu um levantamento da prevalência das infecções por FIV e FeLV no Município de Porto Alegre. Foram analisadas 65 amostras de gatos sadios e doentes. A detecção destas viroses foi realizada utilizando um “kit” comercial de ELISA para ambas as viroses e um protocolo de reação em cadeia da polimerase aninhada (Nested-PCR) para detecção do FIV. Os resultados demonstraram que 21,5% (14/65) dos gatos foram positivos para FIV combinado os resultados de ambos os testes, 10,8% (7/65) foram positivos para FeLV e 6,1% (4/65) foram positivos para ambos os vírus. Foram também realizados hemogramas de 48 animais, dos quais 8 apresentaram resultados positivos para FIV na Nested-PCR. Através do teste T de Student, verificou-se que não houve diferença significativa nos valores hematológicos destes animais. Conclui-se que a utilização do ELISA com a PCR dobrou a chance de detecção de gatos FIV positivos. Desta forma, a prevalência de FIV foi aproximadamente o dobro do que a de FeLV, ao contrário do que ocorre na maior parte de outros locais estudados. / Feline immunodeficiency virus (FIV) belongs to the Lentivirinae subfamily of the Retroviridae family. The infection is characterized by immunodepression and progressive decline in CD4+ T cells that may render the animal susceptible to opportunistic infections. Feline leukemia virus (FeLV) belongs to subfamily Oncovirinae of the Retroviridae family. The virus also affects domestic cats, being an important pathogen that causes a variety of neoplastic disorders and degenerative diseases. Both viruses have a worldwide distribution. The present study aims to determine the prevalence of infection with FIV and FeLV in Porto Alegre municipality. A total of 65 cats were tested, comprising healthy and sick cats. A commercial ELISA kit was used to detect anti-FIV antibodies and FeLV antigen. A nested polymerase chain reaction (Nested-PCR) was also used for FIV provirus detection. The results showed that 21.5% of the sampled cats were positive for FIV in the ELISA and Nested-PCR, 10.8% were positive for FeLV in the ELISA and 6.1% were positive for both viruses. Haemogram of 48 animals were performed but it was not found any significant association between hematologic values of FIV positive and negative animals. It was concluded that the use of ELISA and Nested-PCR increased the possibility to detect FIV positive cats. The prevalence of FIV infected cats was higher than the prevalence of FeLV positive cats, the opposite of what is normally found in studies performed in other regions.

Single molecule experiments study the kinetics of molecular biological systems. Many such studies generate data that can be described by aggregated hidden Markov models, whereby there is a need of doing inference on such data and models. In this study, model selection in aggregated Hidden Markov models was performed with a criterion of maximum Bayesian evidence. Variational Bayes inference was seen to underestimate the evidence for aggregated model fits. Estimation of the evidence integral by brute force Monte Carlo integration theoretically always converges to the correct value, but it converges in far from tractable time. Nested sampling is a promising method for solving this problem by doing faster Monte Carlo integration, but it was here seen to have difficulties generating uncorrelated samples.

The present work proposes visibly pushdown transducers (VPTs) for defining transformations of documents with a nesting structure. We show that this subclass of pushdown transducers enjoy good properties. Notably, we show that functionality is decidable in PTime and k-valuedness in co-NPTime. While this class is not closed under composition and its type checking problem against visibly pushdown automata is undecidable, we identify a subclass, the well-nested VPTs, closed under composition and with a decidable type checking problem. Furthermore, we show that the class of VPTs is closed under look-ahead, and that the deterministic VPTs with look-ahead characterize the functional VPTs transductions. Finally, we investigate the resources necessary to perform transformations defined by VPTs. We devise a memory efficient algorithm. Then we show that it is decidable whether a VPT transduction can be performed with a memory that depends on the level of nesting of the input document but not on its length. / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished