Este trabalho desenvolve um novo método de controle de eficiência energética no acionamento de motores de indução. Esta técnica utiliza um modelo de perdas e uma estrutura de controle baseada no mínimo consumo de energia elétrica. Em um primeiro momento, são apresentados os estudos com os principais controladores de eficiência energética da última década. Depois, são apresentados os modelos elétricos e mecânicos do motor de indução trifásico, a partir do modelo clássico, com o eixo de referência qd0. O controlador utilizado, é o controle por campo orientado indireto (IFOC - Indirect Field Oriented Control), composto por uma malha externa de controle de velocidade e fluxo, e uma malha interna de controle de correntes, que demonstram um bom desempenho de torque e velocidade. Por se tratar de um controlador IFOC, onde os parâmetros do motor são fundamentais para obter bons resultados, o ensaio do motor de indução é realizado e apresentado. Sabendo-se das principais fontes de perdas do motor, o controlador de eficiência energética pode ser elaborado. O controlador baseado no modelo de perdas (LMC -Loss-Model-Based Control) é descrito, assim como o controlador de busca recursiva (SC - Search Control), ambos muito utilizados na literatura. O LMC proposto é implementado através de curvas padrão de fluxo ótimo baseado na potência absorvida, dependendo da carga no eixo do motor, uma nova curva padrão é utilizada. O controlador de eficiência proposto chamado de (MBC - Model Based Control), utiliza o método LMC com um controlador IFOC, este é simulado via software Matlab e verificado experimentalmente através de uma plataforma de acionamento projetada e montada, conforme o projeto descrito. O controlador de eficiência proposto, é comparado com o acionamento de fluxo constante e com o controlador SC, para diferentes perfis de carga no eixo. Para todos os casos o controlador proposto, apresentou o melhor rendimento da máquina. / This paper develops a new method of controlling the drive energy efficiency of induction motors . This technique uses a model of losses and a control structure based on minimum energy consumption . At first , studies with the main drivers of energy efficiency in the last decade are presented . Then the electrical and mechanical models of three-phase induction motor are presented , from the classic model , with the reference axis qd0 . The controller used is an indirect field-oriented control (IFOC), composed of an outer control loop speed and flow , and an inner current control loop , showing a good performance of torque and speed. Because it is a IFOC controller, where the engine parameters are critical to obtain good results , the testing of induction motor is carried out and presented . Knowing the main sources of losses of the engine, the controller of energy efficiency can be drawn . The loss model based (LMC) controller is described , as well as the controller recursive search (SC), both widely used in the literature . The LMC proposed is implemented through optimum standard curves of flow based on power absorbed. Depending on the load on the motor shaft , a new standard curve is used . The proposed controller called efficiency ( MBC - Model Based Control ) uses the LMC method with a IFOC controller , this is simulated via textit software emph Matlab and verified experimentally through a platform drive designed and assembled , as the project described . The controller proposed efficiency is compared with the drive and the constant flow controller SC to different profiles of the axle. For all cases, the proposed controller showed the best performance of the machine.

Image compression aims to reduce the amount of data that is stored or transmitted for images. One technique that may be used to this end is vector quantization. Vectors may be used to represent images. Vector quantization reduces the number of vectors required for an image by representing a cluster of similar vectors by one typical vector that is part of a set of vectors referred to as the code book. For compression, for each image vector, only the closest codebook vector is stored or transmitted. For reconstruction, the image vectors are again replaced by the the closest codebook vectors. Hence vector quantization is a lossy compression technique and the quality of the reconstructed image depends strongly on the quality of the codebook. The design of the codebook is therefore an important part of the process. In this thesis we examine three clustering algorithms which can be used for codebook design in image compression: c-means (CM), fuzzy c-means (FCM) and learning vector quantization (LVQ). We give a description of these algorithms and their application to codebook design. Edges are an important part of the visual information contained in an image. It is essential therefore to use codebooks which allow an accurate representation of the edges. One of the shortcomings of using vector quantization is poor edge representation. We therefore carry out experiments using these algorithms to compare their edge preserving qualities. We also investigate the combination of these algorithms with classified vector quantization (CVQ) and the replication method (RM). Both these methods have been suggested as methods for improving edge representation. We use a cross validation approach to estimate the mean squared error to measure the performance of each of the algorithms and the edge preserving methods. The results reflect that the edges are less accurately represented than the non - edge areas when using CM, FCM and LVQ. The advantage of using CVQ is that the time taken for code book design is reduced particularly for CM and FCM. RM is found to be effective where the codebook is trained using a set that has larger proportions of edges than the test set.

Quick identification of loblolly pine nutrient deficiencies has troubled foresters who wish to increase productivity through fertilization. In the past, extensive field trials were established that did not allow for quick identification of a large number of possibly limiting nutrients in individual stands. This study used single-tree fertilization with macro-nutrients (N, P, K, Ca, Mg, S) and micro-nutrients (Mn, Zn, B, Cu, Fe, Mo) to identify deficiencies using foliar techniques in one growing season. Four study sites in TX, AL, GA, and SC were established in loblolly pine plantations at or near canopy closure. Nutrient concentrations relative to the critical level, optimal nutrient ratios, DRIS methodology, vector analysis, and changes in individual fascicle and total current year foliage weight/area were used to identify deficiencies. Phosphorus was repeatedly indicated as most limiting growth at TX while K was implicated at SC. The GA site revealed multiple deficiencies including N, K, and S. The AL site revealed only a very suspect B deficiency. Critical level methodology was effective in identifying deficiencies of N, P, and K, while B, S, and Cu appeared to be available at sufficient quantities when concentrations were below the published critical levels. Concentrations of S were especially below the critical levels and not increased by fertilization indicating that the critical levels were too high. Nutrient ratio interpretability was reduced by luxury uptake of N in comparison to other deficient nutrients. DRIS methodology was hampered by the inability to create effective comparative norms. Deficiency detection with vector analysis created problems when B and Mn displayed greater uptake relative to controls than the macro-nutrients that provided relative foliage mass increases. Resulting diagnosis indicated deficiencies when B and Mn were really taken up as luxury consumption. Vector analysis may not be as effective as its individual parts. Foliage weight/area responses detected fewer deficiencies than the other techniques. No significant foliar responses were seen at the TX or AL sites. However, K at the SC site was identified as deficient by all foliage mass variables, and multiple deficiencies were detectable at the GA site. / Master of Science

Orientador: Luís Alberto Gobbo / Resumo: A população idosa com idade igual ou superior a 60 anos dobrou na última metade do século XX. O envelhecimento é um processo inevitável com consequências deletérias e progressivas para o corpo humano, comprometendo os seus diferentes sistemas, tais como o fisiológico, o morfológico, o funcional e o endócrino. A perda progressiva de massa e força muscular, associada à função é denominada sarcopenia, e como consequência, promove maior risco para incapacidade funcional, fragilidade, quedas, fraturas, hospitalizações, institucionalizações, óbito precoce e alterações imunológicas. Em idosos as alterações no sistema imunológico podem ocorrer devido ao aumento da concentração sanguínea de citocinas pró-inflamatórias que agrava o estado sarcopênico, acarretando um processo de inflamação crônica de baixo grau (LGI, low grade inflammation). Dentre os parâmetros observados na avaliação da sarcopenia, a análise de impedância bioelétrica (BIA) vem sendo utilizada há tempo para mensuração dos diferentes componentes corporais dentro do sistema morfológico, especialmente os tecidos adiposo e muscular. Mais recentemente, parâmetros brutos da BIA (R, resistência e Xc, reatância) têm sido utilizados para a avaliação da saúde celular (PhA, ângulo de fase e a análise de vetores de impedância bioelétrica (BIVA, bioimpedance vector analysis). Com a finalidade de reverter ou atenuar os efeitos deletérios do envelhecimento, programas de treinamento físico, mais especificamente o treinamento resistido... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre

CAPES; Fundação Araucária / Este trabalho apresenta a proposta de servomecanismos de velocidade sem o uso de sensores mecânicos (sensorless) utilizando motores de indução trifásicos. É realizada a comparação e proposição de técnicas para estimação de velocidade rotórica, analisando o desempenho em diferentes condições de velocidade e de carga. Para a determinação da técnica de controle, inicialmente, é realizada uma análise da literatura das principais técnicas de controle e estimação de velocidade utilizadas, apresentando suas características e limitações. A técnica proposta para o servomecanismo de velocidade sensorless com motor de indução utiliza controle de campo orientado indireto (IFOC), composto de quatro controladores do tipo proporcional-integral (PI): controlador de fluxo rotórico, controlador de velocidade e controladores de corrente no eixo direto e em quadratura. Como o foco principal do trabalho está na malha de controle de velocidade, foi implementado no Matlab® o algoritmo de mínimos quadrados recursivo (RLS) para identificação dos parâmetros mecânicos, tais como: momento de inércia e coeficiente de atrito. Com isso, os ganhos do controlador da malha externa de velocidade podem ser auto ajustados para compensar eventuais variações dos parâmetros mecânicos. Para a estimação de velocidade são analisadas as técnicas: MRAS por fluxos rotóricos, MRAS por força contra eletromotriz (fcem), MRAS por potência reativa instantânea, escorregamento, phase locked-loop (PLL) e modos deslizantes. É apresentada uma proposição de estimação de velocidade baseada em modos deslizantes, onde é realizada uma modificação na estrutura do observador de fluxo rotórico. Para avaliação das técnicas são realizadas análises teóricas no ambiente de simulação de Matlab® e experimentais na plataforma de acionamentos de máquinas elétricas. O DSP TMS320F28069 foi utilizado para implementação experimental das técnicas de estimação de velocidade e verificação do desempenho das mesmas em uma larga faixa de velocidade, incluindo inserção de carga. A partir dessa análise é realizada a implementação em malha fechada controle de velocidade sensorless com estrutura IFOC. Os resultados demonstraram a real possibilidade de substituição de sensores mecânicos pelas técnicas de estimação propostas e analisadas. Dentre estas, o estimador baseado em PLL demonstrou o melhor desempenho em diversas condições, enquanto a técnica baseada em modos deslizantes apresenta boa capacidade de estimação em regime permanente e robustez a variações paramétricas. / This study presents a proposal of speed servomechanisms without the use of mechanical sensors (sensorless) using induction motors. A comparison is performed and propose techniques for pet rotor speed, analyzing performance in different conditions of speed and load. For the determination of control technique, initially, is performed an analysis of the technical literature of the main control and speed estimation used, with their characteristics and limitations. The proposed technique for servo sensorless speed induction motor uses indirect field-oriented control (IFOC), composed of four controllers of the proportional-integral type (PI): rotor flux controller, speed controller and current controllers in the direct and quadrature shaft. As the main focus of the work is in the speed control loop was implemented in Matlab the recursive least squares algorithm (RLS) for identification of mechanical parameters, such as moment of inertia and friction coefficient. Thus, the speed of outer loop controller gains can be self adjusted to compensate for any changes in the mechanical parameters. For speed estimation techniques are analyzed: MRAS by rotóricos fluxes MRAS by counter EMF, MRAS by instantaneous reactive power, slip, locked loop phase (PLL) and sliding mode. A proposition of estimation in sliding mode based on speed, which is performed a change in rotor flux observer structure is displayed. To evaluate the techniques are performed theoretical analyzes in Matlab simulation environment and experimental platform in electrical machinery drives. The DSP TMS320F28069 was used for experimental implementation of speed estimation techniques and check the performance of the same in a wide speed range, including load insertion. From this analysis is carried out to implement closed-loop control of sensorless speed IFOC structure. The results demonstrated the real possibility of replacing mechanical sensors for estimation techniques proposed and analyzed. Among these, the estimator based on PLL demonstrated the best performance in various conditions, while the technique based on sliding mode has good capacity estimation in steady state and robustness to parametric variations.

CAPES; Fundação Araucária / Este trabalho apresenta a proposta de servomecanismos de velocidade sem o uso de sensores mecânicos (sensorless) utilizando motores de indução trifásicos. É realizada a comparação e proposição de técnicas para estimação de velocidade rotórica, analisando o desempenho em diferentes condições de velocidade e de carga. Para a determinação da técnica de controle, inicialmente, é realizada uma análise da literatura das principais técnicas de controle e estimação de velocidade utilizadas, apresentando suas características e limitações. A técnica proposta para o servomecanismo de velocidade sensorless com motor de indução utiliza controle de campo orientado indireto (IFOC), composto de quatro controladores do tipo proporcional-integral (PI): controlador de fluxo rotórico, controlador de velocidade e controladores de corrente no eixo direto e em quadratura. Como o foco principal do trabalho está na malha de controle de velocidade, foi implementado no Matlab® o algoritmo de mínimos quadrados recursivo (RLS) para identificação dos parâmetros mecânicos, tais como: momento de inércia e coeficiente de atrito. Com isso, os ganhos do controlador da malha externa de velocidade podem ser auto ajustados para compensar eventuais variações dos parâmetros mecânicos. Para a estimação de velocidade são analisadas as técnicas: MRAS por fluxos rotóricos, MRAS por força contra eletromotriz (fcem), MRAS por potência reativa instantânea, escorregamento, phase locked-loop (PLL) e modos deslizantes. É apresentada uma proposição de estimação de velocidade baseada em modos deslizantes, onde é realizada uma modificação na estrutura do observador de fluxo rotórico. Para avaliação das técnicas são realizadas análises teóricas no ambiente de simulação de Matlab® e experimentais na plataforma de acionamentos de máquinas elétricas. O DSP TMS320F28069 foi utilizado para implementação experimental das técnicas de estimação de velocidade e verificação do desempenho das mesmas em uma larga faixa de velocidade, incluindo inserção de carga. A partir dessa análise é realizada a implementação em malha fechada controle de velocidade sensorless com estrutura IFOC. Os resultados demonstraram a real possibilidade de substituição de sensores mecânicos pelas técnicas de estimação propostas e analisadas. Dentre estas, o estimador baseado em PLL demonstrou o melhor desempenho em diversas condições, enquanto a técnica baseada em modos deslizantes apresenta boa capacidade de estimação em regime permanente e robustez a variações paramétricas. / This study presents a proposal of speed servomechanisms without the use of mechanical sensors (sensorless) using induction motors. A comparison is performed and propose techniques for pet rotor speed, analyzing performance in different conditions of speed and load. For the determination of control technique, initially, is performed an analysis of the technical literature of the main control and speed estimation used, with their characteristics and limitations. The proposed technique for servo sensorless speed induction motor uses indirect field-oriented control (IFOC), composed of four controllers of the proportional-integral type (PI): rotor flux controller, speed controller and current controllers in the direct and quadrature shaft. As the main focus of the work is in the speed control loop was implemented in Matlab the recursive least squares algorithm (RLS) for identification of mechanical parameters, such as moment of inertia and friction coefficient. Thus, the speed of outer loop controller gains can be self adjusted to compensate for any changes in the mechanical parameters. For speed estimation techniques are analyzed: MRAS by rotóricos fluxes MRAS by counter EMF, MRAS by instantaneous reactive power, slip, locked loop phase (PLL) and sliding mode. A proposition of estimation in sliding mode based on speed, which is performed a change in rotor flux observer structure is displayed. To evaluate the techniques are performed theoretical analyzes in Matlab simulation environment and experimental platform in electrical machinery drives. The DSP TMS320F28069 was used for experimental implementation of speed estimation techniques and check the performance of the same in a wide speed range, including load insertion. From this analysis is carried out to implement closed-loop control of sensorless speed IFOC structure. The results demonstrated the real possibility of replacing mechanical sensors for estimation techniques proposed and analyzed. Among these, the estimator based on PLL demonstrated the best performance in various conditions, while the technique based on sliding mode has good capacity estimation in steady state and robustness to parametric variations.

This Master’s Thesis was part of the project called Multimodalanalysis at the Depart-ment of Biomedical Engineering and Informatics at the Ume˚ University Hospital inUme˚ Sweden. The aim of the project is to develop multivariate measurement anda,analysis methods of the skeletal muscle physiology. One of the methods used to scanthe muscle is functional ultrasound. In a study performed by the project group datawas aquired, where test subjects were instructed to follow a certain exercise scheme,which was measured. Since there currently is no superior method to analyze the result-ing data (in form of ultrasound video sequences) several methods are being looked at.One considered method is called Independent Vector Analysis (IVA). IVA is a statisticalmethod to find independent components in a mix of components. This Master’s Thesisis about segmenting and analyzing the ultrasound images with help of IVA, to validateif it is a suitable method for this kind of tasks.First the algorithm was tested on generated mixed data to find out how well itperformed. The results were very accurate, considering that the method only usesapproximations. Some expected variation from the true value occured though.When the algorithm was considered performing to satisfactory, it was tested on thedata gathered by the study and the result can very well reflect an approximation of truesolution, since the resulting segmented signals seem to move in a possible way. But themethod has weak sides (which have been tried to be minimized) and all error analysishas been done by human eye, which definitly is a week point. But for the time being itis more important to analyze trends in the signals, rather than analyze exact numbers.So as long as the signals behave in a realistic way the result can not be said to becompletley wrong. So the overall results of the method were deemed adequate for the application at hand. / Multimodalanalys

The Island of Tongatapu, Tonga, was struck by a tsunami on January 15, 2022. Internet was cut off from the island, which made remote sensing a valuable tool for the assessment of damages. Through land cover classification, change vector analysis and log-ratio image differencing, damages caused by the tsunami were assessed remotely in this thesis. Damage assessment is a vital part of both assessing the need for humanitarian aid after a tsunami, but also lays the foundation for preventative measurements and reconstruction. The objective of this thesis was to assess damage in terms of square kilometers and create damage maps. It was also vital to assess the different methods and evaluate their accuracy. Results from this study could theoretically be combined with other damage assessments to evaluate different aspects of damage. It was also important to evaluate which methods would be good to use in a similar event. In this study Sentinel-1, Sentinel-2 and high-resolution Planet Imagery were used to conduct a damage assessment. Evaluating both moderate and high-resolution imagery in combination with SAR yielded plausible, but flawed results. Land cover was computed for moderate and high-resolution imagery using three types of classifiers. It was found that the Random Forest classifier outperforms both CART and Support Vector Machine classification for this study area.  Land cover composite image differencing for pre-and-post tsunami Sentinel-2 images achieved an accuracy of around 85%. Damage was estimated to be about 10.5 km^2. Land cover classification with high-resolution images gave higher accuracy. The total estimated damaged area was about 18 km^2. The high-resolution image classification was deemed to be the better method of urban damage assessment, with moderate-resolution imagery working well for regional damage assessment.  Change vector analysis provided plausible results when using Sentinel-2 with NDVI, NDMI, SAVI and BSI. NDVI was found to be the most comprehensive change indicator when compared to the other tested indices. The total estimated damage using all tested indices was roughly 7.6 km^2. Using the same method for Sentinel-1's VV and VH bands, the total damage was estimated to be 0.4 and 2.6 km^2 respectively. Log ratio for Sentinel-1 did not work well compared to change vector analysis. Issues with false positives occurred. Both log-ratios of VV and VH gave a similar total estimated damage of roughly 5.2 km^2.  Problems were caused by cloud cover and ash deposits. The analysis could have been improved by being consistent with the choice of dates for satellite images. Also, balancing classification samples and using high-resolution land cover classification on specific areas of interest indicated by regional methods. This would circumvent problems with ash, as reducing the study area would make more high-resolution imagery available.

Along with the increasing rate of urbanization takes place in the world, the population keeps shifting from rural to urban areas. China, as the country of the largest population, has the highest urban population growth in Asia, as well as the world. However, the urbanization in China, in turn, is leading to a lot of social issues which reshape the living environment and cultural fabric. A variety of these kinds of social issues emphasize the challenges regarding a healthy and sustainable urban growth particularly in the reasonable planning of urban land use and land cover features. Therefore, it is significant to establish a set of comprehensive urban sustainable development strategies to avoid detours in the urbanization process. Nowadays, faced with such as a series of the social phenomenon, the spatial and temporal technological means including Remote Sensing and Geographic Information System (GIS) can be used to help the city decision maker to make the right choices. The knowledge of land use and land cover changes in the rural and urban area assists in identifying urban growth rate and trend in both qualitative and quantitatively ways, which provides more basis for planning and designing a city in a more scientific and environmentally friendly way. This paper focuses on the urban sprawl analysis in Nanjing, Jiangsu, China that being analyzed by urban growth pattern monitoring during a study period. From 2001 to 2016, Nanjing Municipality has experienced a substantial increase in the urban area because of the growing population. In this paper, one optimal supervised classification with high accuracy which is Support Vector Machine (SVM) classifier was used to extract thematic features from multitemporal satellite data including Landsat 7 ETM+, Landsat 8, and Sentinel-2A MSI. It was interpreted to identify the existence of urban sprawl pattern based on the land use and land cover features in 2001, 2006, 2011, and 2016. Two different types of change detection analysis including post-classification comparison and change vector analysis (CVA) were performed to explore the detailed extent information of urban growth within the study region. A comparison study on these two change detection analysis methods was carried out by accuracy assessment. Based on the exploration of the change detection analysis combined with the current urban development actuality, some constructive recommendations and future research directions were given at last. By implementing the proposed methods, the urban land use and land cover changes were successfully captured. The results show there is a notable change in the urban or built-up land feature. Also, the urban area is increased by 610.98 km2 while the agricultural land area is decreased by 766.96 km2, which proved a land conversion among these land cover features in the study period. The urban area keeps growing in each particular study period while the growth rate value has a decreasing trend in the period of 2001 to 2016. Besides, both change detection techniques obtained the similar result of the distribution of urban expansion in the study area. According to the result images from two change detection methods, the expanded urban or built-up land in Nanjing distributes mainly in the surrounding area of the central city area, both side of Yangtze River, and Southwest area. The results of change detection accuracy assessment indicated the post-classification comparison has a higher overall accuracy 86.11% and a higher Kappa Coefficient 0.72 than CVA. The overall accuracy and Kappa Coefficient for CVA is 75.43% and 0.51 respectively. These results proved the strength of agreement between predicted and truth data is at ‘good’ level for post-classification comparison and ‘moderate’ for CVA. Also, the results further confirmed the expectation from previous studies that the empirical threshold determination of CVA always leads to relatively poor change detection accuracy. In general, the two change detection techniques are found to be effective and efficient in monitoring surface changes in the different class of land cover features within the study period. Nevertheless, they have their advantages and disadvantages on processing change detection analysis particularly for the topic of urban expansion.

Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2017-07-11T22:36:03Z No. of bitstreams: 1 Rafael Tosta Santos - Dissertacao Final.pdf: 20325954 bytes, checksum: bc011c09cd83ca73255a8b092923400a (MD5) / Made available in DSpace on 2017-07-11T22:36:03Z (GMT). No. of bitstreams: 1 Rafael Tosta Santos - Dissertacao Final.pdf: 20325954 bytes, checksum: bc011c09cd83ca73255a8b092923400a (MD5) Previous issue date: 2016-05-31 / This master thesis presents a model of deterministic propagation for waveguides with transmitting antenna above the top of the buildings and the equation for the diffraction at the top of the buildings. From the model developed by Dr. Edgar Silva Jr., adaptations are made to consider buildings of different heights along a waveguide. It is developed especially for this work calculations for diffraction at the top for a more accurate model. All the equipment and software used in the process of collection and preparation of the measured data, the sites used for model validation in the city of Feira de Santana - BA and S?o Paulo - SP, in Brazil, the construction of the 3D model and extraction sites database using Google Earth are described. Comparisons with measured values are show that the developed model can be a useful tool in signal envelope behavior analysis for waveguides with antennas above the top of the buildings. / Este trabalho de mestrado apresenta um modelo de propaga??o determin?stico para guias de ondas com antena transmissora acima do topo dos pr?dios e o equacionamento para as difra??es no topo dos pr?dios. A partir do modelo desenvolvido pelo Dr. Edgar Silva J?nior, s?o realizadas adapta??es para considerar constru??es de diferentes alturas ao longo de um guia de ondas. Sendo desenvolvido especialmente para este trabalho c?lculos para difra??o no topo para maior precis?o do modelo. S?o descritos todos os equipamentos e softwares utilizados no processo de coleta e prepara??o dos dados medidos, os locais utilizados para a valida??o do modelo na cidade de Feira de Santana - BA e S?o Paulo - SP no Brasil, a constru??o do modelo 3D e extra??o da base de dados dos locais utilizando o Google Earth. As compara??es com valores medidos mostram que o modelo desenvolvido pode ser uma ferramenta ?til na an?lise do comportamento do sinal para guias de ondas com antenas acima do topo dos pr?dios.