An implementation of a series interconnection scheme for small distributed generation systems is presented in this thesis. The concept uses one set of voltage source converter to control the injected voltage magnitude and phase angle for power injection and voltage sag mitigation. Because of the use of series interconnection scheme, the energy storage device outputs vary concurrently with the line loading and provides loading leveling functions. Under voltage sag situations, it provides missing voltage to effectively deal with power quality problems. The control algorithm uses the reference voltage tracking concept. A signal phase 484 VA prototype of the proposed system is implemented. The performance of the proposed method is simulated and verified by using Matlab-simulink package and the implemented module.

Shape memory alloys (SMA’s) are a family of metals that exhibit properties of pseudo-elasticity / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2009.

Magíster en Estrategia Internacional y Política Comercial / No autorizada por el autor para ser publicada a texto completo / El presente estudio considera como objetivo identificar y analizar la gestión del cambio en todos los ámbitos posiblemente impactados al interior del Servicio Agrícola y Ganadero con la implementación de la Ventanilla Única de Comercio Exterior en Chile. Sin embargo, en el transcurso del estudio se puede visualizar que el estado de avance del proyecto de ventanilla única no permite identificar el impacto final de su implementación, ya que actualmente se encuentra en un estado de levantamiento de procesos, es decir, en etapas intermedias de la implementación del proyecto. Por dicha razón, es que el presente estudio considera los diseños, arquitecturas, modelamientos, armonización y normativa consideradas inicialmente para la elaboración del proyecto, pudiendo estas ser diferentes de los modelos a utilizar en la implementación final. Así como también las observaciones finales solo pueden abarcar aspectos del proyecto piloto sin la puesta en marcha del mismo. Este estudio considera el material bibliográfico existente sobre el tema tanto a nivel nacional como internacional, entrevistas a actores relevantes del proyecto en Chile y el análisis e integración entre ellas. Las observaciones obtenidas del presente estudio concluyen, que con el avance del proyecto de implementación de la Ventanilla Única de Comercio Exterior existente en la actualidad, el Servicio Agrícola y Ganadero ha debido moldearse en algunos aspectos para lograr la integración como Servicio a este impulso gubernamental, si bien no ha podido detectarse el impacto final de la implementación del mismo, existe varios puntos de interés que permiten observar factores de éxito y desafíos del proyecto en Chile.

Current practices of power quality mitigation in the industry are characterized by sub-optimal investment decisions where over compensation is often the norm such causing huge wastage in financial resources. Providing power quality management services to industrial customers in the form of power quality contracts could yield substantial return for the network operator. With better understanding of network parameters, and the option of installing network level mitigation devices, network operators could employ wider range of cost effective mitigation solutions. Tapping into the market however, entails bearing the risks for the customers which network operators are not always willing or encouraged to do. With potentially millions at stake, extensive risk assessments are crucial for any proposed power quality management scheme. This thesis investigates the voltage sag aspect of the problem as part of a larger power quality management scheme. The aim is to develop general framework for technical and financial assessments of voltage sags prior to the introduction of power quality management service. The thesis focuses on five major aspects of voltage sag assessment: identification of customer requirement, financial loss assessment, network sag performance estimation, sag mitigation, and financial appraisal of mitigating solutions. The first part of the thesis gives a comprehensive overview of current power quality problems faced by industrial customers and provides ranges of typical financial losses incurred by different types of industries around the world. It then proposes robust methodology for assessment of typical financial loss, i.e., customized customer damage function (CCDF), for a given industry based on available survey data and taking into account characteristics of the assessed customer plant. For failure and financial risk assessments, the thesis introduces new customer models employing probabilistic methods to quantify risks induced by voltage sags and proposes generic models that incorporate full flexibility in failure risk assessment, taking into account the effect of unbalanced sags on equipment behavior. It further quantifies the error introduced by sag performance estimation using limited monitoring data with a case study on actual sag profile. It demonstrates how different estimation methods and different durations of monitoring period affect accuracy of estimation of voltage sag profile and associated risk of industrial process failure. Following this, the thesis presents new models for plant and network level sag mitigation devices. They include power injecting mitigation devices, devices that reduce number of faults in the network and devices that reduce the severity of faults. Developed models are then used to investigate the cost-effectiveness of sag mitigation at different levels. Finally, the thesis presents Genetic Algorithm based methodology for deciding on optimal investment scheme in voltage sag mitigation in the network. The sensitivity of the solution to various influential parameters, including plant type and size, sensitive equipment type, process characteristics, financial loss resulting from process interruption, cost and effectiveness of mitigating solution and network fault rates is also established.

Memoria para optar al título de Ingeniero Civil Mecánico / La minería en Chile es uno de los rubros de la economía más relevantes para el país y debido a los desafíos de competitividad que enfrentamos a nivel global, es necesario avanzar en establecer mejoras de productividad y costos en los procesos mineros, los cuales involucran variados equipos, cuya operación y mantención afectan la productividad y costos del proceso. Muchos de estos equipos requieren repuestos, partes y piezas que deben ser fabricadas. Durante los años 2000 al 2005 a cargo del área de Ingeniería y Control Producción de División Talleres de Codelco Chile, el autor de este trabajo, preparó y diseñó sistemas de alimentación para fundir revestimientos de molinos, chancadoras y otras piezas para variados equipos de la industria minera. Con el fin de fomentar el uso de métodos de fabricación para piezas fundidas estandarizados, traspasar la experiencia acumulada y oportunidades de mejora en costos y plazos con el uso de nuevas tecnologías, el objetivo de este trabajo es diseñar el proceso de fabricación de un revestimiento de Molino SAG (lifter) para la etapa de validación de pieza prototipo o primera pieza, que permite iniciar la producción total de un conjunto de revestimientos. El alcance de este trabajo incluye desde el diseño del sistema de alimentación del prototipo, hasta el análisis de resultados, con una validación teórica y verificación práctica de los resultados; además de una estimación de costos y determinación de oportunidades de mejora que aseguren una pieza fundida de acuerdo a las especificaciones establecidas. Existen muchas restricciones para la fabricación de piezas fundidas, asociadas fundamentalmente a la infraestructura y equipamiento disponible por los fabricantes, variables que afectan la productividad y el costo de fabricación. Se concluye que se cumplieron los objetivos de este trabajo, se estudió y diseñó el proceso de fabricación de un lifter de molino SAG y se logró fabricar una pieza prototipo que cumpliera con las especificaciones establecidas. Se determinaron oportunidades de mejora en los costos y plazos de fabricación. Del análisis y estudio realizado se confirma que la experiencia en la fabricación de piezas fundidas es clave para diseñar y establecer un método de alimentación, ya que las estimaciones y cálculos nos determina sólo una propuesta de solución para la alimentación de la primera pieza a fundir y no necesariamente una solución final. Conocer las limitaciones del proceso de fabricación y la presencia en terreno para validar la propuesta, son dos aspectos claves en el diseño y definición del método de alimentación.

Research groups around the world are looking to develop a qubit protected from decoherence for achieving quantum advantage in computations. This would have huge impact on the modern world. The applications are many from drug development to cryptography and many more  elds. Indium-Arsenide Nanowires with an epitaxially matched thin  lm of lead grown with Select-Area-Growth could prove to be a platform for building scalable qubits. The work in this thesis is to create a device capable of measuring the superconductivity of the samples InAs-Pb grown at the Center for Quantum Devices, Niels Bohr Institute. The InAs semiconducting nanowires serves as one dimensional system that could host Majorana Zero Modes if coupled to a superconductor such as Pb. The MZMs emerges at the edges of the nanowires. The device created is a 4-probe device that should be used to measure the induced topological superconductivity inside the device. The project was able to such a device using electron beam lithography techniques and development of the fabrication process of InAs-Pb SAG NW Devices was furthered.

Em um trabalho anterior, foi avaliada a variabilidade de Sarcocystis spp. isolados de gambás oriundos do estado do Rio Grande do Sul pesquisando sequências gênicas codificadoras de antígenos de superfície (SAGs). Os resultados indicaram haver linhagens de isolados de Sarcocystis (relacionadas geneticamente a S. falcatula) que trocam genes em prováveis processos de recombinação sexual. A proposta deste estudo foi de conhecer as variações gênicas e relações filogenéticas em Sarcocystis spp. isolados de gambás através da análise de loci gênicos de genoma mitocondrial (CytB), de genoma de apicoplasto (ClpC) e das regiões espaçadoras transcritas internas (ITS-1), comparando a diversidade encontrada nestes grupos com a observada em integrantes da sub-familia Toxoplasmatinae. E também de conhecer a diversidade de genes codificadores de SAG-2, SAG-3 e SAG-4. Neste estudo foram obtidos esporocistos de Sarcocystis spp. através de raspado intestinal e fezes provenientes de gambás do gênero Didelphis, oriundos do Estado de São Paulo, Rio Grande do Sul e Rio Grande do Norte. Os marcadores moleculares CytB, ClpC e ITS-1 revelaram uma ampla variabilidade genotípica e alelos inéditos entre os isolados do Brasil. Os resultados levam a crer que é possível a existência de espécies “híbridas” de Sarcocystis no Brasil, com mistura de genes de ambas as espécies. Em relação aos genes codificadores de SAGs, foi encontrada uma diversidade ainda maior do que trabalho similar realizado. Os resultados sugerem uma possível ocorrência de reassortment e recombinação de alelos em sequências SAGs, contribuindo ainda mais para a geração de variabilidade e consequentemente na configuração antigênica do parasito. Estes resultados demonstram que isolados brasileiros possuem uma composição genética diferente do reportado em demais localidade, o que pode ter reflexos importantes no conhecimento da diversidade das espécies de Sarcocystis que infectam gambás em nosso meio e em toda a epidemiologia das infecções produzidas pelos protozoários deste grupo / A great variability in surface antigens genes (SAGs) of Sarcocystis spp. sporocysts was found in a previous study, through the intestinal scraping technique of opossums from the south region of Brazil. The results indicated probable sexual recombination between lineages of Sarcocystis isolates (genetically related to Sarcocystis falcatula). The aim of this research is the study of genetic variability and phylogenetic relationships among Sarcocystis spp. isolates from captured opossums in Brazil, by the analysis of molecular markers less subjected to selective pressure, such as DNA barcode, for this purpose, genetic loci from mitochondrial (CytB) and apicoplast genome (ClpC), and internal transcribed spacer regions (ITS-1) were applied and compare the results with the diversity found within members of the Toxoplasmatinae sub-family. The diversity among the SAG-2, SAG-3 and SAG-4 genes was also studied. The Sarcocystis sporocysts were obtained from opposum’s intestinal scraping and faeces from São Paulo State, Rio Grande do Sul State and Rio Grande do Norte State, Brazil. The molecular markers CytB, ClpC and ITS-1 revealed a vast genotypic variability and novel alleles among the Brazilian isolates. The results indicate possible existence of hybrid species of Sarcocystis in Brazil, with a gene mixture from both species. Regarding the SAG genes, an even greater variability was found than previously reported. The results also suggest the occurrence of reassortment and allele recombination of SAG sequences, contributing even more to the variability and thus in the parasites antigenic configuration. In this study, the results demonstrate that isolates from Brazil have a different genetic composition than reported in other locations, which may have important impacts in the knowledge of the diversity of Sarcocystis species shed by opossums in our environment and in all of the epidemiology of infections of protozoa of this particular group

Orientador: Didier Gastmans / Resumo: A necessidade do estudo os diferentes processos do ciclo hidrológico de forma integrada tem se tornado cada vez mais urgente, uma vez que o uso do termo “crise hídrica” se torna cada vez mais frequente. Nesse sentido, a determinação de taxas de recarga e quantificação dos fluxos subterrâneos, aliados ao uso de isótopos estáveis (2H e 18O), que são excelentes traçadores da movimentação da água no ciclo hidrológico, impulsionaram esse estudo, buscando gerar informações científicas fundamentais para uma melhor gestão dos recursos hídricos. Situada numa porção de afloramento do Sistema Aquífero Guarani (SAG), a área de estudo está inserida em uma pequena bacia hidrográfica na porção oeste do estado de São Paulo, onde as águas subterrâneas e superficiais são responsáveis pelo abastecimento de inúmeras cidades da região. O estudo teve como principal objetivo compreender a dinâmica entre os diversos compartimentos do ciclo hidrológico, buscando mudanças nos padrões de precipitação e de recarga subterrânea, por métodos de fácil aplicação, como balanço hídrico e flutuações dos níveis d’água (WTF), bem como a aplicação de traçadores isotópicos (δ2H e δ18O) em diferentes sazonalidades. Ao considerar a sazonalidade dos dados isotópicos na chuva, águas superficiais e subterrâneas, pode-se observar que os valores de δ18O são mais empobrecidos durante a estação chuvosa e mais enriquecidos durante a estação seca. A diferença entre os sinais isotópicos permitiu compreender a movimentação da á... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The need to study the different processes of the hydrological cycle in an integrated way has become increasingly urgent since the use of the term "water crisis" becomes more and more frequent. In this sense, the determination of rates of recharge and quantification of the underground flows, together with the use of stable isotopes (2H and 18O), which are excellent tracers of water movement in the hydrological cycle, stimulated this study, seeking to generate scientific information fundamental to better management of water resources. Located in a portion of the outcrop of the Guarani Aquifer System (SAG), the study area is in a small hydrographic basin in the western portion of the state of São Paulo, where groundwater and surface waters are responsible for the supply of numerous cities located there. The main objective of this study is to understand the dynamics between the various compartments of the hydrological cycle, searching for changes in precipitation and underground recharge patterns, using easy-to-apply methods such as water balance and water level fluctuations (WTF), as well as the application of isotopic tracers (δ2H and δ18O) in different seasonal conditions. When considering the seasonality of the isotopic data in rainfall, surface water, and groundwater, it can be observed that δ18O values are more depleted during the rainy season and more enriched during the dry season. The difference between the isotopic signals allowed to understand the movement of the water... (Complete abstract click electronic access below) / Doutor

Voltage sag (dip), a sudden reduction of the voltage magnitude within a short duration in power system, is one of major concerns of power quality problems. The main reason of the increased concerns for voltage sag problems is that the losses caused by voltage sag events are high and not negligible. Reliability indices have been used for many years to quantify the effect of sustained interruptions on the electric power system. Power quality indices reflecting the severity of various power quality problems, such as flicker, harmonics, voltage swell and sag conditions, power factor, losses, electromagnetic interference, and other phenomena, are still under development. The representation and classification of voltage sags have been studied recently by standard-setting organizations. In order to find compatibility between service quality and the equipment adopted and a least cost solution for possible power quality problems, the concept of system disturbance level and equipment immunity level was proposed in IEC 61000-3-7 but without clear definitions. A novel voltage sag index based on fuzzy logic technique to quantify system disturbance and equipment immunity levels is proposed in this dissertation. This approach takes network vulnerability, equipment sensitivity and uncertainties in measuring voltage sags into account, thereby, providing meaningful information for both the utility and customers. Using the proposed method, the probabilistic distribution of system disturbances can be obtained from the single event indices of all events recorded and the probabilistic distribution of equipment sag immunity capability can be evaluated based on the device voltage sag tolerance curve. This dissertation also presents a novel framework for predicting the number of equipment disruptions due to voltage sags in a unit of time by using the disturbance and immunity levels concepts. In the proposed approach, the number of disruptions is computed by using the unreliability concept. The area of overlapping between the distributions of site disturbance and equipment immunity levels, which indicates the number of possible disruptions, is calculated based on interference theory and reliability computations. The presented methodology can be used as a planning tool to quantify the system disturbances and equipment sensitivity. It can also be used to perform cost analysis of the compatibility of equipment with an electric power system. To minimize the costs due to voltage sags, it is always a good strategy to maintain a minimum overlap between the equipment immunity level and site disturbance level to have satisfactory operation of the equipment. The tool achieved in this work can be used to perform such analyses.

Made available in DSpace on 2014-12-17T14:10:22Z (GMT). No. of bitstreams: 1 AndreaDM_DISSERT.pdf: 1136289 bytes, checksum: 4971fd9b2aab3f08935061c736892689 (MD5) Previous issue date: 2010-03-31 / Toxoplasmosis is one zoonosis caused by Toxoplasma gondii protozoan. Goats, amongst the production animals, are one of the species most susceptible to this parasite, being one them main involved agents in ovine and goat abortions, determining great economic losses and implications for public health, since the presence it parasite in the products of goat origin, consist in one of the main sources of infection for the man. In this study 244 blood samples in 8 farms situated in 4 cities from the Sert?o do Cabugi region, Rio Grande do Norte State, northeast of Brazil and, tested by ELISA assay. The results had shown a prevalence of 47.13% for anti- T. gondii antibodies and a significant association between positivity and variable evaluated as age, locality and property. The IgG avidity assay evaluated in 115 positive samples was carried to discriminate acute and chronic infection. Twelve samples (10.4%) had presented antibodies of low avidity while 103 (89.6%) presented high avidity antibodies; indicating that most of the animals was precocious exposure to the parasite. Significant difference was verified only for the variable sex. We also evaluate the capacity of recombinant adenoviruses codifying SAG1, SAG2, SAG3 and CMV in inducing activation of specific immune response in goat. These 109 animals received 109 pfu of the AdSAG1, AdSAG2, AdSAG3, AdCMV or PBS in vaccine protocol with 3 immunizations. Serum samples of the each animal, before and after mmunization, had been submitted to the ELISA. The results demonstrate that the immunizations had induced the production of IgG antibodies specific against T. gondii proteins / A toxoplasmose ? uma zoonose causada pelo protozo?rio Toxoplasma gondii. Os caprinos, dentre os animais de produ??o, s?o uma das esp?cies mais suscet?veis a este parasito, sendo um dos principais agentes envolvidos no abortamento de ovinos e caprinos, determinando grandes perdas econ?micas e tendo implica??es para sa?de p?blica, j? que a presen?a do parasita nos produtos de origem caprina, constituem-se em uma das principais fontes de infec??o para o homem. Neste estudo foram coletadas 244 amostras de sangue em 8 fazendas situadas em 4 munic?pios da regi?o do Sert?o do Cabugi, Estado do Rio Grande do Norte, regi?o Nordeste do Brasil e testadas atrav?s do Ensaio Imunoenzim?tico (ELISA). Os resultados obtidos mostraram uma preval?ncia de 47,13% para anticorpos anti-T. gondii e uma associa??o significativa entre positividade e as vari?veis avaliadas tais como idade, localidade e propriedade. Foi realizado o ensaio IgG de avidez em 115 amostras positivas com o intuito de discriminar infec??o aguda e cr?nica. Doze amostras (10,4%) apresentaram anticorpos de baixa avidez enquanto 103 (89,6%) anticorpos de alta avidez; indicando que a maior parte dos animais foi exposto ao parasita precocemente. Foi verificada diferen?a estat?stica significativa apenas para a vari?vel sexo. Avaliamos tamb?m a capacidade de adenov?rus recombinantes codificando SAG1, SAG2, SAG3 e CMV em induzir ativa??o de resposta imune em caprinos. Estes animais receberam 109 pfu de AdSAG1, AdSAG2, AdSAG3, AdCMV ou PBS em protocolo vacinal com 3 imuniza??es. Amostras de soro obtidas dos animais, antes e ap?s cada imuniza??o, foram submetidas ao ELISA. Os resultados demonstram que as imuniza??es induziram a produ??o anticorpos IgG espec?ficos contra as prote?nas de T. gondii