“Accent” is the pattern of speech pronunciation by which one can identify a person’s linguistic, social or cultural background. It is an important source of inter-speaker variability and a particular problem for automated speech recognition. The aim of the study was to investigate a new computational approach to accent classification which did not require phonemic segmentation or the identification of phonemes as input, and which could therefore be used as a simple, effective accent classifier. Through a series of structured experiments this study investigated the effectiveness of Support Vector Machines (SVMs) for speech accent classification using time-based units rather than linguistically-informed ones, and compared it to the accuracy of other machine learning methods, as well as the ability of humans to classify speech according to accent. A corpus of read-speech was collected in two accents of English (Arabic and “Indian”) and used as the main datasource for the experiments. Mel-frequency cepstral coefficients were extracted from the speech samples and combined into larger units of 10 to 150ms duration, which then formed the input data for the various machine learning systems. Support Vector Machines were found to classify the samples with up to 97.5% accuracy with very high precision and recall, using samples of between 1 and 4 seconds of speech. This compared favourably with a human listener study where subjects were able to distinguish between the two accent groups with an average of 92.5% accuracy in approximately 8 seconds. Repeating the SVM experiments on a different corpus resulted in a best classification accuracy of 84.6%. Experiments using a decision tree learner and a rule-based classifier on the original corpus gave a best accuracy of 95% but results over the range of conditions were much more variable than those using the SVM. Rule extraction was performed in order to help explain the results and better inform the design of the system. The new approach was therefore shown to be effective for accent classification, and a plan for its role within various other larger speech-related contexts was developed.

Axonal degeneration is a major pathological feature of the central nervous system (CNS) inflammatory demyelinating disease multiple sclerosis (MS). This axonal degeneration has major consequences, as functional axonal regeneration in the CNS is largely absent. Cumulative axonal degeneration is the likely cause of the majority of progressive MS-related disability, and therefore, the need for novel neuroprotective therapies for MS exists. Experimental autoimmune encephalomyelitis (EAE), an animal model of MS pathology, also produces axonal injury. In particular, the optic nerve and spinal cord are key sites of neuroinflammation in mouse EAE. By utilizing this model, the short term and long term effects of the putative neuroprotective cytokine, leukaemia inhibitory factor (LIF), were investigated in the optic nerve and spinal cord utilising a number of outcome measures of axonal dysfunction. These included MRI measures of water diffusivity along (ADC ||) and across (ADC┴) the optic nerves, serum levels of phosphorylated neurofilament heavy chain subunit (pNF-H) and histological morphometric measures. LIF treatment reduced EAE grade and pNF-H plasma levels, decreased ADC┴, but had no effect on ADC ||, axon counts or inflammatory infiltration. / In contrast, genetic deletion of LIF and its sister cytokine ciliary neurotrophic factor (CNTF), not only increased EAE grade and pNF-H levels, but also decreased optic nerve ADC|| and optic nerve and spinal cord axon densities. After reviewing current literature, we hypothesize that the target cell for endogenously upregulated LIF in EAE may be the neuron or axon, whereas the target cell for exogenously administered therapeutic LIF may be another cell type, possibly infiltrating macrophages and activated microglial cells. LIF antagonist treatment did not have any affect on EAE grade, pNF-H levels or MRI parameters. This lack of effect may be due to the inability of the LIF antagonist to enter the CNS, supporting the hypothesis that endogenous LIF has a centrally acting mechanism.

Made available in DSpace on 2015-03-26T13:32:22Z (GMT). No. of bitstreams: 1 texto completo.pdf: 434501 bytes, checksum: 0ab5e3021a0cbd11c8c868f09b269488 (MD5) Previous issue date: 2014-02-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The analysis of growth curves of animals has been widely used to increase the efficiency of beef cattle ranching. Related to growth curves with nonlinear mixed models strategic, studies have strategic applications in genetic improving programs in defining selection criteria for earliness and weight gain, aimed at, that for each individual is estimated a random coefficient, facilitating identification and selection of more efficient animals based on the coefficients. This methodology considers the variability between and within individuals. The objective of this study was to evaluate the efficiency of the adjustment of growth curves by nonlinear mixed models. Nonlinear models, Michaelis-Menten Modified, Logistic, von Bertalanffy, Gompertz, Richards and Brody, were fitted, with and without the incorporation of random effects for analysis of growth in beef cattle Tabapuã race. For comparison between fixed and mixed models were used the following adjustment quality evaluators: Akaike s information criterion (AIC), Bayesian information criterion (BIC), mean absolute deviation (DMA), mean square error (MSE) and coefficient of determination (R2). The use of nonlinear mixed model was efficient to describe bovine growth curves. / A análise de curvas de crescimento de animais tem sido muito utilizada para aumentar a eficiência da pecuária de corte. Estudos relacionados a curvas de crescimento com modelos não lineares mistos podem ter aplicações estratégicas em programas de melhoramento genético na definição de critérios de seleção para precocidade e ganho de peso, tendo em vista, que para cada indivíduo é estimado um coeficiente aleatório, facilitando a identificação e seleção de animais mais eficientes com base nos coeficientes. Essa metodologia considera a variabilidade entre e dentro de indivíduos. O objetivo deste trabalho foi avaliar a eficiência do ajuste de curvas de crescimento através de modelos não lineares mistos. Foram ajustados os modelos não lineares Michaelis-Menten Modificado, Logístico, von Bertalanffy, Gompertz, Richards e Brody, com e sem a incorporação de efeitos aleatórios para análise de curva de crescimento de bovinos de corte da raça Tabapuã. Para comparação entre modelos fixos e mistos foram utilizados os seguintes avaliadores de qualidade de ajuste: critério de informação de Akaike (AIC), critério de informação bayesiano (BIC), desvio médio absoluto (DMA), erro quadrático médio (EQM) e coeficiente de determinação (R2). A utilização de modelos não lineares mistos foi eficiente para descrever curvas de crescimento de bovinos.

The A15-based Nb3Sn and V3Ga superconducting compounds are an integral part of synchrotrons and magnetic fusion reactor technology, especially where a magnetic field higher than 10 T is required, which lies beyond the limit of conventional Nb-Ti superconductors (~8 T). These brittle intermetallic compounds are difficult to manufacture in the form of wires, required for the application purpose, using the traditional wire-drawing process. Hence, bronze technique is adopted to fabricate such filamentary wires. This is based on the solid-state diffusion where A3B compound (A=Nb or V, B=Sn or Ga) forms during the interaction of Cu(B) and A. The operation of pure superconducting wires gets restricted to the field of 12 T, however, the ever-increasing demands for an improved efficiency have promoted the development of these A15 wires with the addition of alloying elements such as Ti and Zr. Many important physical and mechanical properties of such wires depend on the growth behaviour of these compounds. Therefore, understanding the growth of such compounds necessitates an in-depth analysis on diffusion behaviour of various elements in both bronze-based solid solutions as well as A15-intermetallics. Estimation of diffusion parameters makes use of the most commonly used diffusion couple technique. There are mainly three methods available for the estimation of the interdiffusion coefficients, proposed by Matano-Boltzmann (MB), Den Broeder (dB), same as Sauer-Freise (SF) and Wagner. Among these three, MB treatment is known to be the least accurate method, especially when there is a deviation of molar volume in a system from the ideality. At the same time molar volume might affect the estimation process differently for dB and Wagner’s approach. MB method is still being used neglecting the actual molar volume variation. On the other hand, the implementation of dB or Wagner’s approach for the estimation remains to be random. For the first time, we have critically examined the role of molar volume on estimated diffusion parameters and indicated the more accurate approach. Similar analysis for the estimation of the intrinsic diffusion coefficient is conducted considering Heumann and van Loo’s methods. Furthermore, the discussion is extended to the estimations of various diffusion parameters considering the measured composition profile in the V-Ga system. A detailed diffusion study has been conducted on Cu(Ga) and Cu(Sn) solid solutions to examine the role of the vacancy wind effect on interdiffusion. The interdiffusion, intrinsic and impurity diffusion coefficients are determined to facilitate the discussion. It is found that Ga and Sn are the faster diffusing species in the respective systems. The trend of the interdiffusion coefficients is explained with the help of the driving force. Following that, the tracer diffusion coefficients of the species are calculated with and without consideration of the vacancy wind effect. We found that the role of the vacancy wind is negligible on the minor element in a dilute solid solution, which is the faster diffusing species in this system and controls the interdiffusion process. However, consideration of this effect is important to understand the diffusion rate of the major element, which is the slower diffusing species in this system. Major drawback of studying diffusion in multi-component systems is the lack of suitable techniques to estimate the diffusion parameters. In this study, a generalized treatment to determine the intrinsic diffusion coefficients in multi-component systems is developed utilizing the concept of pseudo-binary approach. This is explained with the help of experimentally developed diffusion profile in the Cu(Sn, Ga) solid solution. Based on an interdiffusion study using an incremental diffusion couple in the V-Ga binary system, we have shown that V diffuses via lattice, whereas Ga does so via grain boundaries for the growth of the V3Ga phase. We could estimate the contributions from two different mechanisms, which are, usually, difficult to delineate in an interdiffusion study. Available tracer diffusion studies and the atomic arrangement in the crystal structure have been considered for a discussion on the diffusion mechanisms. Diffusion–controlled growth rate of V3Ga at the Cu(Ga)/V changes dramatically because of a small change in Ga content in Cu(Ga). One atomic percent increase in Ga leads to more than double the product phase layer thickness and a significant decrease in activation energy. Kirkendall marker experiment indicates that V3Ga grows because of diffusion of Ga. Role of different factors influencing the diffusion rate of Ga and high growth rate of V3Ga are discussed. The growth of Nb3Sn by bronze technique on two different single crystals and deformed Nb is studied. The grain boundary diffusion-controlled growth rate is found to be different for each of these three specimens. The difference is explained on the basis of the grain size of Nb3Sn. Elemental additions such as Ti and Zr to either bronze or metal are found to improve the superconducting properties. We have examined their effects on the growth rates of A15-phase formed in Cu(B,x)/A and Cu(B)/(A,x), where x is Ti or Zr. In either cases Ti and Zr-additions result in an improved growth rate of the product phase and reduces activation energy with increase in alloying addition; however few precipitates are formed in the interdiffusion zone for Cu(B,x)/A. Wavelength dispersive spectrometry (WDS)-mapping reveals these to be x-rich. Scanning transmission electron microscopy (STEM)-analysis suggests having composition gradient inside a single precipitate. TEM-diffraction demonstrates these to be Ti(A) solid solution crystallizing as BCC-structure for Cu(B,Ti)/A. These are located on grain boundaries of A15-phase. Electron back-scattered diffraction (EBSD)-analysis demonstrates grain morphology of product phase and found the average grain size to exhibit a decreasing trend with increasing x content. Columnar grains, on Ti and Zr addition tend to form as equiaxed ones. Based on the morphology and grain size pattern, the role of grain boundary diffusion is speculated to have a dominant effect with increase in elemental additions. The texture evolution of the product phase is also investigated and found the product phase to grow as a strongly textured one with the elemental additions. A peculiar pattern is observed for the texture of the product phase and its adjacent A or A(x) grains.

La caractérisation de texture est centrale dans de nombreuses applications liées au traitement d’images. L’analyse de textures peut être envisagée dans le cadre mathématique de l’analyse multifractale qui permet d’étudier les fluctuations de la régularité ponctuelle de l’amplitude d’une image et fournit les outils pratiques pour leur évaluation grâce aux coefficients d’ondelettes ou aux coefficients dominants. Bien que mise à profit dans de nombreuses applications, l’analyse multifractale souffre à présent de deux limitations majeures. Premièrement, l’estimation des paramètres multifractaux reste délicate, notamment pour les images de petites tailles. Deuxièmement, l’analyse multifractale a été jusqu’à présent uniquement considérée pour l’analyse univariée d’images, alors que les données à étudier sont de plus en plus multivariées. L’objectif principal de cette thèse est la mise au point de contributions pratiques permettant de pallier ces limitations. La première limitation est abordée en introduisant un modèle statistique générique pour le logarithme des coefficients dominants, paramétrisé par les paramètres multifractaux d’intérêt. Ce modèle statistique permet de contrebalancer la variabilité résultant de l’analyse d’images de petite taille et de formuler l’estimation dans un cadre bayésien. Cette approche aboutit à des procédures d’estimation robustes et efficaces, que ce soit pour des images de petites ou grandes tailles. Ensuite, l’analyse multifractale d’images multivariées est traitée en généralisant ce cadre bayésien à des modèles hiérarchiques capables de prendre en compte l’hypothèse d’une évolution lente des propriétés multifractales d’images multi-temporelles ou multi-bandes. Ceci est réalisé en définissant des lois a priori reliant les propriétés dynamiques des paramètres multifractaux des différents éléments composant le jeu de données. Différents types de lois a priori sont étudiés dans cette thèse au travers de simulations numériques conduites sur des images multifractales multivariées synthétiques. Ce travail est complété par une étude du potentiel apport de l’analyse multifractale et de la méthodologie bayésienne proposée pour la télédétection à travers l’exemple de l’imagerie hyperspectrale. / Texture characterization is a central element in many image processing applications. Texture analysis can be embedded in the mathematical framework of multifractal analysis, enabling the study of the fluctuations in regularity of image intensity and providing practical tools for their assessment, the coefficients or wavelet leaders. Although successfully applied in various contexts, multi fractal analysis suffers at present from two major limitations. First, the accurate estimation of multifractal parameters for image texture remains a challenge, notably for small sample sizes. Second, multifractal analysis has so far been limited to the analysis of a single image, while the data available in applications are increasingly multivariate. The main goal of this thesis is to develop practical contributions to overcome these limitations. The first limitation is tackled by introducing a generic statistical model for the logarithm of wavelet leaders, parametrized by multifractal parameters of interest. This statistical model enables us to counterbalance the variability induced by small sample sizes and to embed the estimation in a Bayesian framework. This yields robust and accurate estimation procedures, effective both for small and large images. The multifractal analysis of multivariate images is then addressed by generalizing this Bayesian framework to hierarchical models able to account for the assumption that multifractal properties evolve smoothly in the dataset. This is achieved via the design of suitable priors relating the dynamical properties of the multifractal parameters of the different components composing the dataset. Different priors are investigated and compared in this thesis by means of numerical simulations conducted on synthetic multivariate multifractal images. This work is further completed by the investigation of the potential benefit of multifractal analysis and the proposed Bayesian methodology for remote sensing via the example of hyperspectral imaging.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A descoberta de reservatórios de petróleo na camada do pré-sal abriu novas perspectivas para a economia brasileira. A grandes profundidades, com elevado teor de CO2 e submetidos a altas pressões e temperaturas, a exploração de petróleo das camadas de pré-sal constitui um considerável desafio tecnológico. Neste contexto, o conhecimento dos coeficientes de compressibilidade são fundamentais para o estudo do comportamento termodinâmico e escoamento dos fluidos destes campos de produção. Com este objetivo, foram determinadas experimentalmente nesta dissertação a massa específica e a velocidade do som de sistemas envolvendo quatro hidrocarbonetos puros: n-decano, n-hexadecano, decalina e tetralina, assim como para sistemas multicompostos envolvendo estes hidrocarbonetos e para uma amostra de condensado de petróleo. Os resultados obtidos permitiram o cálculo dos coeficientes de compressibilidade isentrópica, isotérmica e isentálpica. É apresentada uma avaliação sobre a capacidade de se correlacionar dados experimentais de velocidade do som aos dados calculados pelas equações de estado de Peng-Robinson e Lee-Kesler com regras de mistura: (i) Spencer e Danner e (ii) Lee-Kesler / The discovery of oil reservoirs in the pre-salt layer has opened new perspectives for Brazilian economy. In deep waters, with high levels of CO2 and subjected to high pressures and temperatures, the oil exploration in the pre-salt layer is a considerable technological challenge. In this context, knowledge of compressibility coefficients and phase equilibrium data are essential for studying the thermodynamic behavior and flow in these oil fields. With this objective, experimental data were obtained for density and sound velocity in systems involving four pure hydrocarbons: n-decane, n-hexadecane, decalin and tetralin, as well as in multi-component systems involving these hydrocarbons, and in a sample of oil condensate. The results obtained allowed the calculation of isentropic, isothermal and isenthalpic compressibility coefficients. An evaluation on the ability to correlate experimental data of sound velocity with data calculated from Peng-Robinson and Lee-Kesler equations of state with mixing rules: (i) Spencer and Danner and (ii) Lee-Kesler is presented

abstract: The operating temperature of photovoltaic (PV) modules is affected by external factors such as irradiance, wind speed and ambient temperature as well as internal factors like material properties and design properties. These factors can make a difference in the operating temperatures between cells within a module and between modules within a plant. This is a three-part thesis. Part 1 investigates the behavior of temperature distribution of PV cells within a module through outdoor temperature monitoring under various operating conditions (Pmax, Voc and Isc) and examines deviation in the temperature coefficient values pertaining to this temperature variation. ANOVA, a statistical tool, was used to study the influence of various factors on temperature variation. This study also investigated the thermal non-uniformity affecting I-V parameters and performance of four different PV technologies (crystalline silicon, CdTe, CIGS, a-Si). Two new approaches (black-colored frame and aluminum tape on back-sheet) were implemented in addition to the two previously-used approaches (thermally insulating the frame, and frame and back sheet) to study temperature uniformity improvements within c-Si PV modules on a fixed latitude-tilt array. This thesis concludes that frame thermal insulation and black frame help reducing thermal gradients and next best viable option to improve temperature uniformity measurements is by using average of four thermocouples as per IEC 61853-2 standard. Part 2 analyzes the temperature data for two power plants (fixed-tilt and one-axis) to study the temperature variation across the cells in a module and across the modules in a power plant. The module placed in the center of one-axis power plant had higher temperature, whereas in fixed-tilt power plant, the module in north-west direction had higher temperatures. Higher average operating temperatures were observed in one-axis tracking as compared to the fixed-tilt PV power plant, thereby expected to lowering their lifetime. Part 3 focuses on determination of a thermal model coefficients, using parameters similar to Uc and Uv thermal loss factors used in PVsyst, for modules of four different PV technologies experiencing hot-desert climate conditions by statistically correlating a year-long monitored data. Thermal models help to effectively quantity factors influencing module temperatures to estimate performance and energy models. / Dissertation/Thesis / Masters Thesis Mechanical Engineering 2016

Toppeffekter används av elnätsbolag för att dimensionera elnätet, vilket blir allt viktigare för varje år. Fler och fler invånare och företag ökar sin elkonsumtion och förväntar sig en driftsäker och stabil elförsörjning. Det finns två vanliga metoder att beräkna toppeffekter. Första sättet är Velanders formel som är en enkel metod för att uppskatta toppeffekter. Velanders formel behöver bara årsenergi och vetskap om kundkategori med tillhörande Velanderkonstanter för beräkning av uppskattad toppeffekt. Sedan finns den mer komplexa typkurvemetoden som behöver flera olika parametrar, t.ex. graddagtal, dygnsmedeltemperatur, gränssannolikhet och kundkategori. Detta examensarbete undersöker en enkel metod för att ta fram konstanter till Velanders formel för beräkning av toppeffekter. Detta genomfördes med hjälp av regressionsanalys av historiska elanvändningsdata från Mälarenergi Elnät AB:s (MEE) kunder från 12 olika kundkategorier. Detta på grund av att MEE önskade att utveckla en metod för att ta fram konstanter till Velanders formel baserad på historiska elanvändningsdata. Metoden för att ta fram konstanter till Velanders formel går ut på att med hjälp av MATLAB utföra en regressionsanalys på simulerade kundgrupper skapade från timvis historiska elanvändningsdata. En kurva baserad på Velanders formel tas sedan fram som beskriver den övre gränsen till toppeffekterna för de simulerade kundgrupperna. Från kurvan fås sedan de Velanderkonstanter som söks. Resultaten av den undersökta metoden presenteras i form av grafer och tabeller för tre utvalda kundkategorier. Alla kategorier och deras resultat finns som bilagor till rapporten. Valideringen av resultaten och metoden gjordes med hjälp av korsvalidering och jämförelse mot heterogena simulerade kundgrupper. Känslighetsanalysen visar att den undersökta metoden var känslig för flera faktorer såsom kategorisering av kunder, tidsspann för historiska elanvändningsdata, antal simulerade kundgrupper och kundantal. Med tillräcklig dimensionering av dessa faktorer bedömdes metoden vara användbar. Resultaten visade på att de framtagna Velanderkonstanterna gav en god uppskattning av toppeffekter för de kundkategorier som undersökts. Jämförelse av de uppskattade toppeffekterna och de observerade visade på att det fanns en viss differens mellan dem. Detta var dock förväntat eftersom de uppskattade toppeffekterna ska avspegla den övre toppeffektsgränsen. / This degree project has examined a simple method aiming to obtain coefficients for Velanders formula which purpose is to calculate peak loads. This was done by using regression analysis on historical data on consumption of electricity from 12 different customer categories acquired from Mälarenergi Elnät AB (MEE). The reason being that MEE wanted to examine a method which could obtain coefficients for Velanders formula based on hourly historical electricity consumption data. The method for obtaining Velander coefficients uses MATLAB to do regression analysis on simulated customer groups, created from hourly historical electricity consumption data. The Velander coefficients are then obtained from a regression curve based on Velanders formula. Results from the evaluation of the method is presented with the help of plots and tables for three chosen customer categories. Validation of the method was done by cross-validation and comparison against heterogeneous customer groups. Sensitivity analysis showed the examined method to be sensitive to several factors such as categorization of customers, the timespan of historical electricity consumption data, the number of simulated customer groups that were used and how many customers a category contained. By dimensioning these factors carefully, the method examined was assessed to be viable. The results indicated that the obtained Velander coefficients gave a good estimation of the peak loads for the chosen customer categories. Comparison between the estimated and observed peak loads indicated that there was a certain difference between them. This was to be expected since the estimated peak loads are to reflect the upper peak load limit.

Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2018-02-21T12:40:45Z No. of bitstreams: 1 PGPV15MA182.pdf: 576083 bytes, checksum: 30203f1600225b3bef1ac5a58e2caece (MD5) / Made available in DSpace on 2018-02-21T12:40:45Z (GMT). No. of bitstreams: 1 PGPV15MA182.pdf: 576083 bytes, checksum: 30203f1600225b3bef1ac5a58e2caece (MD5) Previous issue date: 2015-09-30 / Embrapa / To continue moving forward in terms of getting new wheat cultivars, more productive and more stable, it is necessary to increase the genetic variability made available to the breeder and increase the frequency of favorable alleles in new cultivars. As a contribution to these goals it studied the selection of parents possessing combining ability and superior genetic potential. In this sense the work was divided into two chapters. The first objective was to evaluate the performance of the parent wheat using multivariate techniques in order to obtain genotypes that approximate a ideotype. 16 genotypes were sown. Four commercial cultivars (BRS 331, CD 124, BRS Parrudo and Marfim). Six F1 hybrids obtained by artificial crosses between cultivars, forming a complete diallel without reciprocals. Six progenies of these crossings in the F2 generation. The treatments were arranged in a randomized complete block design with three replications. Were measured in all plants of the plots, five phenotypic variables: days from emergence to heading, plant height, peduncle length, number of ears per plant and grain yield per plant. Through multivariate contrasts, there were comparisons of interest which were significant. Standardized canonical coefficients were used to determine the importance of each variable on the significance of employed to Mahalanobis distance as dissimilarity measure contrasts. Among the evaluated intersections BRS 331 x CD 124 and BRS Parrudo x Marfim show the greatest genetic variability and Marfim x CD 124 does not have genetic dissimilarity to the set of characters studied. Cross only elite genotypes is not recommended for the provision of genetic variability. In the second chapter the objectives of this study were: i) estimate general and specific combining abilities through diallel analysis in order to identify crossings most likely to generate segregating populations with superior performance; ii) verify the existence of reciprocal effect on the evaluated hibrids. Were evaluated four varieties, Marfim, BRS Parrudo, BRS 331 and CD 124, using the the method 1 (p2 all combinations with reciprocal) of Griffing (1956). Five phenotypic variables were observed. Days from emergence to heading (DEE). Plant height (EST), measured in centimeters from the ground to the top of the ear, without considering the awn. Peduncle length (PED), measured in centimeters, distance from the last internode to the base of the main stem spike. Number of ears per plant (NEP), counting the spikes that formed grains. Grain yield per plant (MGP), measured in grams. They were estimated the general combining ability (GCA), specific combining ability (SCA) and the reciprocol effects (REC) of the traits of interest. The following conclusions were obtained: a) the assessed parents are contrasting and there is genetic variability for the studied characters; b) is greater the importance of the GCC and additive effects in the genetic control of observed variables, c) the effect of CGC's parent Marfim is increased NEP and MGP, the BRS Parrudo is to increase DEE, CD 124 is to decrease DEE, the BRS 331 is to reduce all traits; e) the CD 124 x BRS 331 crossing has reciprocal effect increasing DEE when CD 124 is used as a female / Para continuar avançando em termos de obtenção de novos cultivares de trigo, mais produtivos e mais estáveis, torna-se necessário aumentar a variabilidade genética posta à disposição do melhorista e aumentar a frequência de alelos favoráveis nas novas cultivares. Como forma de contribuir para estes objetivos foi estudada a seleção de genitores que possuam capacidade combinatória e potencial genético superior. Nesse sentido o trabalho foi dividido em dois capítulos. No primeiro o objetivo foi avaliar o desempenho de genitores em trigo através de técnicas multivariadas com o intuito de obter genótipos que se aproximem de um ideotipo. Foram semeados 16 genótipos. Quatro cultivares comerciais (BRS 331, CD 124, BRS Parrudo e Marfim). Seis híbridos F1 obtidos por cruzamentos artificiais entre os cultivares, formando um dialelo completo, sem os recíprocos. Seis progênies destes cruzamentos na geração F2. Os tratamentos foram dispostos em blocos completos casualizados, com três repetições. Foram mensuradas, em todas as plantas das parcelas, cinco variáveis fenotípicas: dias da emergência ao espigamento, estatura da planta, comprimento do pedúnculo, número de espigas por planta e massa de grãos por planta. Através de contrastes multivariados, verificaram-se quais comparações de interesse foram significativas. Foram utilizados coeficientes canônicos padronizados para determinar a importância de cada variável na significância dos contrastes Empregou-se a distância generalizada de mahalanobis como medida de dissimilaridade. Entre os cruzamentos avaliados BRS 331 x CD 124 e BRS Parrudo x Marfim apresentam a maior variabilidade genética e Marfim x CD 124 não apresentam dissimilaridade genética para o conjunto de caracteres estudados. O cruzamento apenas de genótipos elite não é recomendado para a disponibilização de variabilidade genética. No segundo capítulo os objetivos deste trabalho foram: i) estimar capacidades gerais e específicas de combinação através de análise dialélica com o intuito de identificar cruzamentos com maior possibilidade de gerar populações segregantes com desempenho superior; ii) verificar a existência de efeito recíproco nos cruzamentos avaliados. Foram avaliados quatro cultivares, Marfim, BRS Parrudo, BRS 331 e CD 124, utilizando-se o o método 1 (todas as p2 combinações com os recíprocos) de Griffing (1956). Foram observadas cinco variáveis fenotípicas. Dias da emergência ao espigamento (DEE). Estatura da planta (EST), medida em centímetros, do solo até o topo da espiga, sem considerar as aristas. Comprimento do pedúnculo (PED), medido em centímetros, distância do último entrenó até a base da espiga do colmo principal. Número de espigas por planta (NEP), contagem das espigas que formaram grãos. Massa de grãos por planta (MGP), medido em gramas. Foram estimadas a capacidade geral de combinação (CGC), a capacidade específica de combinação (CEC) e o efeito recíproco (REC) dos caracteres de interesse. Foram obtidas as seguintes conclusões: a) os genitores avaliados são contrastantes e existe variabilidade genética para os caracteres estudados; b) é maior a importância da CGC e dos efeitos aditivos no controle genético das variáveis observadas, c) o efeito da CGC do genitor Marfim é de aumento do NEP e MGP, do BRS Parrudo é de aumentar DEE, do CD 124 é de diminuir DEE, do BRS 331 é de diminuir todos os caracteres avaliados; d) o cruzamento CD 124 x BRS 331 apresenta efeito recíproco diminuindo DEE quando CD 124 é utilizado como fêmea

Made available in DSpace on 2016-12-12T17:38:37Z (GMT). No. of bitstreams: 1 Paulo Sergio Dainez - resumo.pdf: 31972 bytes, checksum: 94a24928564b90b196513e814cfe09a3 (MD5) Previous issue date: 2010-06-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In the resonant linear compressor the piston is drive by a linear actuator and a resonant mechanical spring directly in the reciprocating motion, this is a mass spring resonant system, eliminating bearing and crank of the conventional reciprocating compressors, and the friction loss has a significant reduction. The maximum displacement of the piston is regulating by the equilibration between the power supply by the actuator and the power transfer to the gas compression process. This type of the compressor is design to work at the resonant frequency of the mass spring system, in this condition the efficiency is maximum. Then the control must drive the linear actuator in the maximum displacement of the piston and adjust the drive frequency at the system resonant frequency. For enable of this process is necessary that piston position is known with precision, however the installation of a sensor have same difficulty, since the refrigeration compressor is hermetic system, and it have high pressure and temperature, with wide range of variation. This work develop the implementation of a full order linear observer to estimate the displacement and the velocity of the piston of the resonant linear compressor, and a control system able to drive the compressor in the maximum piston displacement and in the resonant frequency, and only measured a current of the linear actuator, without sensor inside de compressor. For this a nonlinear model of the compressor and a linear model with variable coefficients for the observer are develop, also a simulator of the system is develop, where the compressor model is controlled by the displacement and the velocity signals calculate by observer, demonstrated the feasibility of the proposed technique in the present work. / Nos compressores lineares ressonantes o pistão é acionado por um atuador linear e molas diretamente no sentido do seu movimento alternativo, formando um sistema massa-mola ressonante, eliminando assim os mancais mecânicos e o sistema biela e manivela dos compressores convencionais, reduzindo de forma significativa as perdas por atrito. A amplitude do deslocamento do pistão é regulada pelo equilíbrio da potência fornecida pelo atuador e a potência transferida para o processo de compressão do gás. Estes compressores são projetados para funcionar na frequência de ressonância do sistema massa-mola, nesta condição a eficiência do sistema é máxima. Assim, o controle deve acionar o atuador linear na máxima amplitude de deslocamento do pistão e ajustar a frequência de acionamento na frequência de ressonância do sistema. Para viabilizar este processo é necessário que o curso do pistão seja conhecido com precisão, porém a instalação de um sensor apresenta dificuldades, pois os compressores de refrigeração são herméticos e estão sujeitos a pressões e temperaturas elevadas e com grande faixa de variação. Este trabalho propõe a implementação de um observador de estados de ordem plena, para estimar o deslocamento e a velocidade do pistão do compressor linear ressonante, e um sistema de controle capaz de acionar o compressor no deslocamento máximo e na frequência de ressonância, medindo somente a corrente no atuador linear, sem a necessidade de sensores instalados dentro do compressor. Para isto desenvolve-se um modelo não linear do compressor e um modelo linear equivalente de coeficientes variáveis para o projeto do observador, também é desenvolvido um simulador do sistema, onde o modelo do compressor é controlado pelos sinais de deslocamento e velocidade calculados pelo observador, demonstrando a viabilidade da técnica proposta no presente trabalho.