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Characterisation of organic materials for photovoltaic devicesLewis, Andrew J. January 2006 (has links)
This thesis presents an investigation into a wide range of potential materials for organic photovoltaic (PV) devices. A variety of optical techniques are used to define physical parameters for each material such as the photoluminescence quantum yield (PLQY), absorption coefficient and exciton diffusion length. Electrical characterisation is used to determine the optimal structure for devices fabricated with these materials. A number of novel materials are presented in this thesis. These include new polymers, both soluble and precursor, and a relatively new class of material, the conjugated dendrimer. These are highly configurable branching molecular structures that enable fine tuning of material properties. Work on polymers presented in this thesis investigates how such materials can be improved by testing the effect of small changes to their molecular structure. One of these changes had significant effects upon the overall material characteristics. The introduction of a dipole across a polymer successfully created a charge separating material without the need for an extra species such as C60 to be present. The introduction of the conjugated dendrimer to PV applications allows significant scope for molecular engineering. Dendrimers enable tight control over certain aspects of the molecular properties. Small changes can be made such as colour tuning or solubility that enable optimisation to be performed on the molecular level, rather than on device structure. Such changes produced significantly higher internal quantum efficiencies (> 90%) than typical polymer devices and offer the prospect of power conversion efficiencies in excess of 10%. Time-resolved luminescence (TRL) spectroscopy was used to characterise the behaviour of photogenerated excitons within organic films. The investigation of exciton diffusion length was performed upon two polymers, each utilising two different time-resolved methods; diffusion to a quencher and exciton-exciton annihilation. It was found that diffusion in polythiophene films is anisotropic and the photoluminescence lifetime is dependent upon film thickness. This is explained by the formation of self-ordered microstructures during the spin coating process. Data modelling was performed which took into account both the thickness variation and the interaction of excitons with a quenching interface producing a much more realistic approach than previously published work.
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Novi metod analize rada fotonaponskog sistema u uslovima varijacije sunčevog zračenja / A new method of analyzing the photovoltaic power plant works under variation of solar radiationČorba Zoltan 20 May 2016 (has links)
<p style="text-align: justify;">Rad se bavi problemom smanjenja proizvodnje<br />električne energije fotonaponske elektrane u<br />uslovima promenljivog zračenja. Predlaže se novi<br />metod analize rada u uslovima senčenja putem makro- i<br />mikrorekonfiguracije FN polja, koja povećava<br />proizvodnju električne energije.</p> / <p>The paper presents the problem of reducing electricity<br />production of PV power plant under variation of solar<br />radiation conditions. The author proposed a new method of<br />analysis PV power plant works under partial shading<br />condition trough micro- and macroconfiguration of PV array.</p>
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DESIGN OF A TECHNO-ECONOMIC OPTIMIZATION TOOL FOR SOLAR HOME SYSTEMS IN NAMIBIAHolmberg, Aksel, Pettersson, Oscar January 2016 (has links)
The expansion of the electrical grid and infrastructure is an essential part of development since it contributes to improved standard of living among the population. Solar home systems (SHS) are one solution to generate electricity for households where the national grid does not reach or is too sparsely populated to build a local mini-grid. Solar home system programs have been used as a solution for rural electrification in developing countries all over the world with various success, one of these countries is Namibia. A large fraction of the population in Namibia lacks access to electricity where most of the people live in rural areas not reached by the national electrical grid. However, several SHS clients in Namibia have been dissatisfied with their systems due to several issues regarding the service providers. Several service providers have limited technical know-how and therefore frequently over- and undersize system components and make mistakes during installations. An opportunity to improve SHS in Namibia is to develop a software tool that service provider can use to quickly calculate an optimum SHS in a user friendly way based on the electricity demands of the clients. An optimization model was developed using MS Excel which calculates the optimal SHS component capacities regarding cost and reliability with the use of Visual Basic macros. Various field studies and sensitivity analyses were conducted with the MS Excel model. The results were validated and compared with other software programs such as PVsyst and a Matlab model used in a previous study regarding solar power. Results show that several components in existing systems are incorrectly sized and that the MS Excel model could improve future installations and improve the reputation of SHS. The sensitivity analyses focused on cost, system reliability, system size and PV-module tilt and were implemented in the MS Excel model to optimize the results in a techno-economic perspective. The MS-Excel model was approved by Namibia Energy Institute and will be available for all service providers in Namibia.
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Solcellsfasader - En jämförelse av celltyper och infästningssystemKhalaf, Bahuz January 2019 (has links)
In line with the expansion of the building industry, future projects like buildings and infrastructure require high demands on energy issues. EU directives and major global goals constantly set guidelines for what should be done and not. Construction and architecture companies in Sweden can influence what future cities will look like. This requires knowledge in these issues, not least about solar cell facades. Solar panels are mostly applied to roofs and big fields directed upwards towards the sun, but could one imagine solar cells integrated or applied to the facade of a building? This is what this thesis is about, and how the market looks today for these technologies in 2019. Therefore, the purpose is to compare solar cell technologies and attachment possibilities on facades of buildings. The goal is to give architects insight into how they are and can be used for future facade solutions. Most of the work has consisted of literature studies from books, reports research and the internet. The results turned out to be that the techniques are under a maturing phase after intensive research has been made in the field of solar cells, as well as increased use, lower prices and more efficient techniques. Today, it is possible to utilize solar cell facades in Sweden and other countries around the world. The sun is a renewable energy source that can cover the majority of the world's energy and electricity needs.
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Micro-grids supplied by renewable energy : Improving technical and social feasibilityBastholm, Caroline January 2019 (has links)
Universal access to electricity stands high on the global agenda and is regarded as essential for positive development in sectors such as health care, education, poverty reduction, food production and climate change. Decentralized, off-grid electrification is deemed an important complement to centralized grid extension. By utilizing a renewable energy source, solar technology for the generation of electricity, photovoltaics (PV) is being considered as a way forward to minimize the environmental problems related to energy use. This thesis aims to contribute to improving the technical and social feasibility of PV and PV-diesel hybrid micro-grids for the purpose of providing access to electricity to people in rural areas of countries with low level access to electricity. In line with these general aims, the focus has been to address three questions related to challenges in three phases of rural electrification. The work has a multi-disciplinary approach, addressing mainly technical and social aspects of long-term sustainability of micro-grids, in a local context, and the changes these are intended to generate. One specific micro-grid in Tanzania has been used as a major case study. The thesis is developed through three papers, all presenting methodologies or aspects for investigation in rural electrification projects and studies in general, and for PV-diesel hybrid micro-grids in particular. Paper I puts forward a methodology to facilitate non-social scientific researchers to take social aspects increasingly into consideration. Paper II is a guideline to support system users to increasingly apply an evaluation based system operation. Paper III specifically highlights the importance to consider blackouts when investigating how an existing off-grid PV-diesel hybrid system shall be utilized when a national grid becomes available.
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Interface de supervisão para uma plataforma experimental de pesquisa e ensino em energia solar fotovoltaicaHafemeister, Augusto 22 May 2018 (has links)
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Previous issue date: 2018-05-22 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / CFC/CRCs - Conselho Federal de Contabilidade / PROSUP - Programa de Suporte à Pós-Gradução de Instituições de Ensino Particulares / O presente trabalho apresenta o desenvolvimento de uma interface de supervisão para integrar duas topologias diferentes de sistemas fotovoltaicos instalados na Unisinos, viabilizando estudos locais e a distância, ou seja, permitindo que alunos e pesquisadores de outras comunidades acadêmicas possam visualizar dados em tempo real e fazer intercâmbio de informações e discussões à cerca deste assunto. Para atingir as metas estabelecidas, o sistema foi desenvolvido sobre o software LabVIEW®, sendo as medições das grandezas elétricas e térmicas enviadas automaticamente para o Microsoft OneDrive®, o qual está em sincronismo com o site da Plataforma Experimental de Pesquisa e Ensino em ESFV. Além da integração dos sistemas mencionados, implementou-se um hardware para ajustar o ângulo de inclinação de um módulo fotovoltaico, agregou-se um traçador de curvas I-V e P-V, o qual permite fazer análises em condições reais de operação e também foram instalados dois sensores para medir a irradiância no plano do gerador fotovoltaico, ambos com monitoramento de temperatura e devidamente calibrados. Contudo, o principal diferencial dessa pesquisa está nos resultados encontrados na utilização da interface, em que foi possível comparar a performance dos módulos variando o ângulo de inclinação, correlacionando-o com a irradiância e a temperatura em diferentes dias típicos. Para um caso específico, foi analisado o comportamento da curva I-V durante um período de sombreamento, onde a eficiência de conversão atingiu menos de 6% e a potência máxima entregue foi 40% menor, mesmo estando coberta apenas uma das 60 células que compõem o módulo. Esse fato reforça a importância da análise experimental da curva característica para avaliação da qualidade e do desempenho do sistema, bem como identificar defeitos nas células e/ou no diodo de bypass. Por fim, simulou-se um modelo matemático, com base nas características do módulo fotovoltaico utilizado, a fim de avaliar os impactos da variação de temperatura e irradiância e também validar os resultados encontrados na prática. / This work presents the development of a supervision interface to integrate two different topologies of photovoltaic systems installed in Unisinos, making possible local and distance studies, allowing students and researchers from other academic communities to view real time data and to exchange information and discussions on this subject. To achieve the established goals, the system was developed over LabVIEW® software, with measurements of electrical and thermal values automatically sent to Microsoft OneDrive®, which is in synchronism with the Photovoltaic Teaching and Research Experimental Platform website. In addition to the integration of the mentioned systems, a hardware was implemented to adjust the angle of inclination of a PV module, an I-V and P-V curve plotter was added, which allows to perform analyzes under real operating conditions and also installed two sensors to measure the irradiance in the plane of the PV generator, both with temperature monitoring and properly calibrated. However, the main difference of this research is in the results found in the use of the interface, in which it was possible to compare the performance of the modules by varying the angle of inclination, correlating it with the irradiance and the temperature on different typical days. For a specific case, the behavior of the I-V curve was analyzed during a shading period, where the conversion efficiency reached less than 6% and the maximum delivered power was 40% lower, even cover only one of the 60 cells that make up the module. This fact reinforces the importance of the experimental analysis of the characteristic curve to evaluate the quality and performance of the system, as well as to identify defects in the cells and/or bypass diode. Finally, a mathematical model was simulated, based on the characteristics of the PV module used, in order to evaluate the impacts of temperature and irradiance variation and to validate the results found in practice.
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Instalação de uma microrrede fotovoltaica conectada/isolada com estocagem e monitoramento com controle da carga alimentadaDias, Ricardo Machado 19 June 2015 (has links)
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Previous issue date: 2015-06-19 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / PROSUP - Programa de Suporte à Pós-Gradução de Instituições de Ensino Particulares / Este trabalho trata do desenvolvimento e do comissionamento de uma microrrede fotovoltaica de 1680 W pico conectada/isolada com estocagem para gerenciamento e controle de uma carga considerada crítica. Esta microrrede, empregando duas tecnologias de módulos, foi instalada no Laboratório de Energias Renováveis da Unisinos. A microrrede é composta de dois painéis de módulos, um de 1080 W de silício multicristalino, e um de 600 W de silício monocristalino. O primeiro é do sistema conectado à rede e o segundo é do sistema isolado, respectivamente. O sistema de gerenciamento e controle, chamado de supervisório, monitora e controla as duas redes através do sistema de aquisição de dados, que possui como tarefa o armazenamento dos dados em um cartão de memória além de mostrar em tempo real as variáveis envolvidas no processo através de um display de cristal líquido. São feitas análises dos valores de correntes e tensões, tanto alternada quanto contínua, para determinação das potências de entrada e de saída dos equipamentos envolvidos no processo, como também variáveis como temperatura ambiente e do painel FV e irradiância. A proposta deste estudo é demonstrar a disponibilidade do sistema para satisfazer uma carga que pode ser considerada como um processo crítico, a fim de entregar uma potência constante para a carga. Para isto, é necessário que a carga seja comutada entre os sistemas conectado à rede e isolado de acordo com as variáveis analisadas pelo sistema de aquisição de dados. As análises dos dados são divididas em duas partes: sistema FV conectado à rede e sistema isolado. Para cada sistema, foi analisado o comportamento da tensão, corrente e potência dos painéis fotovoltaicos, assim como o comportamento dos inversores e banco de estocagem de energia, considerando dias com céu claro e céu nublado. Para o dia de céu claro analisado, foi injetado na rede da concessionária 5,8 kWh de energia. A eficiência global, ηs deste sistema conectado ficou na ordem de 9 %. O sistema de aquisição de dados e controle da microrrede mostrou-se adequado com o propósito de alimentar a carga em permanência. Sempre que a rede da concessionária é desligada, a carga é automaticamente direcionada para o sistema isolado. Quando o banco de estocagem atinge 50 % de sua capacidade, a carga volta a ser alimentada pelo sistema conectado em paralelo com a rede da concessionária. / This work deals with the development and commissioning of a photovoltaic micro-grid 1680 W connected/alone with storage for management and control of a load considered critical. This micro-grid, employing two PV modules technologies, was installed on Renewable Energy Laboratory at Unisinos. The micro-grid panels is composed of two modules, a 1080 W multicrystalline silicon, and a 600 W of monocrystalline silicon. The first is a grid-connected system and the second is a stand-alone system, respectively. The management and control system, called supervisory, monitors and controls the two systems via data acquisition, which has the task of storing the data on a memory card in addition to showing real-time variables involved in the process through a liquid crystal display. Are made analysis of current values and voltages, AC and DC, to determine the input and output power of the equipment involved in the process, as well as variables such as ambient temperatures and PV module and irradiance. The purpose of this study is to prove availability of the system to meet a load that can be considered as a critical process, in order to maintain a constant power to the load. For this, it is necessary that the load is switched between systems connected to the grid and alone, according to the variables analyzed by the data acquisition system. The analyzes of the data are divided into two parts: PV grid-connected and alone system. For each system, the behavior of tension was analyzed, current and power of the PV panels, as well as the behavior of inverters and power storage bank, considering days with clear skies and overcast sky. For clear sky days analyzed, it was injected into the mains 5.8 kWh of energy. The overall efficiency of this system connected, ηs is 9 %. The data acquisition and control system micro-grid was adequate for the purpose of feeding a remaining charging. Whenever, the mains is switched off, the load is automatically directed to the alone system. When the storage capacity of the database reaches 50%, the load is once again powered by the connected system in parallel with the utility grid.
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Investigation into using Stand-Alone Building Integrated Photovoltaic System (SABIPV) as a fundamental solution for Saudi rural areas and studying the expected impactsAlbaz, Abdulkarim January 2015 (has links)
A number of natural resources can be exploited for providing energy, such as the sun, wind, water flow, tides, waves and deep heat generated within the earth. Recently, renewable resources especially that extracted from solar have been significantly encouraged mainly for environmental worries, such as climate change mitigation and global warming, coupled with high oil cost and security and economic matters. The crucial need of energy in human development has also been another important drive pushing the rapid progresses in renewable technologies, which results in both large-scale strategic projects for covering wide urban and rural areas and simple systems suitable for individual buildings. Solar energy has become a widely desired option, especially in high solar radiation areas. The Middle East, especially Gulf region is an ideal geographical area for solar power where it has one of the highest solar irradiation rates across the world. The population in Gulf Cooperation Council (GCC) countries is significantly small compared to the geographical areas and populations are distributed mostly throughout huge areas forming small villages and rural communities on substantial distances from the main power networks. In Saudi Arabia, there is a crisis in supplying enough electricity to the large cities and domestic remote area in various parts in the country and a wide range of remote areas still suffer from a severe shortage of power supply. In this project, the opportunity of using small-scale solar energy technologies, such as Stand-Alone Building-Integrated PV (SABIPV) systems has been investigated as an optimal solution for providing solar energy to a great deal of off-grid areas in Kingdom of Saudi Arabia and the expected short and long-term impacts of such solution have been studied. The study showed that the main reasons behind the crisis in supplying electricity to domestic remote and rural off-grid areas in Saudi Arabia are the weakness of the financial returns compared to the cost of providing the service, the difficulty of the natural topography of areas, high cost of maintenance works, and the regulations of providing electric services in Saudi Arabia. This is in addition to the expected environmental impacts, such as raising the pollution rates in the area and the safety influences of extending the high voltage lines over huge areas. On the other hand, the lack of the necessary infrastructure services, particularly electricity and the looking forward for better level of prosperity lead people who live in countryside and remote areas usually to immigrate to in-grid areas which has several short and long-term negative impacts on economic, social and security sides. This study shows that SABIPV system is a cost-Impactive, powerful, and fundamental solution for all off-grid areas in Saudi Arabia including remote villages and rural communities and providing the same level of electricity services that can be achieved in urban on-grid areas. The system is expected to have positive impacts including reducing pollution and greenhouse gas emissions, the expansion of agricultural land and reduce desertification, reducing the influence of high-voltage electrical lines on living organisms, providing adequate electricity service at lower cost, offering more job opportunities for people in remote areas, increasing agricultural and handicraft products, developing the tourism sector in rural areas, reducing the rate of migration from rural areas to the cities, and reducing the slum areas in cities which helps to reduce the rate of crimes, ignorance, the low level of morality, and health and environmental problem.
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Cancro bacteriano (Xanthomonas campestris pv. viticola) da videira (Vitis spp): métodos de preservação e crescimento de isolados;escala diagramática e reação de variedades de videira à doençaNASCIMENTO, Ana Rosa Peixoto 11 February 2005 (has links)
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Previous issue date: 2005-02-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The Submédio São Francisco is the main producting and exporting region of table grapes in Brazil, where the cultivated area with this fruit crop has been significantly expanded in the last years. However, the intensification of grape production, the use of susceptible cultivars, and the favorable environmental conditions of that region allowed the occurrence of disease and pest problems, with emphasis for the bacterial canker (Xanthomonas campestris pv. viticola - Xcv). Reported for the first time in Brazil, in plantations of the Submédio São Francisco in 1998, the canker is the most important bacterial disease of grapevine in that region. The present work aimed to study: methods of preservation and pathogen growth at different temperatures, pHs and NaCl concentrations; elaboration and validation of a diagramatic key for bacterial canker; and the reaction of grapevine varieties to the pathogen, based on the disease epidemiological components. The preservation methods: dried paper strips (DPS), periodic transfer (PT), sterile distiled water (SDW) and dried leaves (DL) were utilised for storing two Xcv strains during 12 months. The variables viability and pathogenicity were evaluatedmonthly and estimated by bacterial growth and area under disease incidence curve (AUDIC). Both the DPS and SDW methods maintained 100% of cell viability and showed higher AUDIC values during 11 months. PT did not permit growth at 30 days while DL allowed the pathogen isolation for 5 months. The influence of temperature (0, 5, 10, 15, 20, 25, 27, 28, 29, 30, 35, 40 and 45°C), pH (5.0; 5.5; 6.0; 6.5; 7.0; 7.5; 8.0; 8.5 and 9.0) and NaCl concentration (1, 2, 3, 4, 5, 6 and 7%) on the growth of two Xcv strains was studied in NYD medium and evaluated in spectrophotometer. The minimum and maximum temperatures for Xcv growth were respectively 5 and 39°C, while the optimum growth was observed from 27 to 29°C. Xcv does not growth at 0 or 40°C. The optimum pH for Xcv growth ranged from 7.0 to 7.5. The pathogen growth declined from 3.0 % NaCl and was null at 6.0 %. Aiming to standardize methods to quantify bacterial canker severity a diagrammatic key was elaborated including the levels 2, 4, 8, 17, 34, 63 and 91% of diseased leaf area. To validate the diagrammatic key, 50 leaves with different levels of severity, previously measured by the softwareAutoCAD®, were evaluated by 10 raters with and without the use of the key. Two evaluations were performed with the key at 7-day intervals when different sequences of the same leaves were visually estimated by the same raters. The accuracy and precision of each rater were determined by simple linear regression between actual and estimated severity. Without the key, most of the raters overestimated disease severity. With the key raters obtained better levels of accuracy and precision; however, all tended to underestimate severity, with absolute errors concentrated around 10%. Raters showed good repeatability and high reproducibility of estimative by using the key compared to not using it. The reaction of 20 grapevine varieties, 13 scions and seven rootstocks, was evaluated in relation to disease resistance under greenhouse conditions. Plants were inoculated with a suspension of the strain Xcv1 (A570 = 108 CFU mL-1), incubated in a greenhouse and observed daily for epidemiological components of bacterial canker: incubation period (PI), incidence of leaves with symptoms (INC), incidence of leaves with canker (IFC), disease severity (SEV), progress rate of disease incidence (TPID), area under the disease severity progress curve (AACPSD). All varietieswere susceptible to the pathogen, although there were significant differences among them (P=0.05) for most of the analyzed variables. ‘Brasil’ showed the highest disease levels for all variables tested, while ‘Isabel’ and ‘Paulsen 1103’ presented the highest values of PI and the lowest values of INC, IFC, SEV, TPID and AACPSD, suggesting the potential of those varieties in programs of genetic breeding and integrated management of grapevine bacterial canker. The studied variables might be utilized in research including reaction of varieties to this disease. Considering all the epidemiological components, the analysis of the Euclidean distance by UPGMA allowed the separation of scion and rootstock varieties into three similarity groups each. / O Submédio São Francisco é o principal centro produtor e exportador de uvas de mesa do Brasil, onde a área plantada com esta cultura tem se expandido significativamente, nos últimos anos. No entanto, a intensificação do cultivo da videira, o plantio de variedades suscetíveis, além das condições climáticas prevalentes na região propiciam o surgimento de problemas fitossanitários, entre os quais se destaca o cancro bacteriano (Xanthomonas campestris pv. viticola - Xcv). Detectado pela primeira vez no Brasil, em parreirais do Submédio São Francisco, em 1998, o cancro é a doença bacteriana mais importante da videira na região. No presente trabalho foram estudados: métodos de preservação e o crescimento do patógeno em diferentes temperaturas, pHs e concentrações de NaCl; elaboração e validação de uma escala diagramática para cancro bacteriano; e reação de variedades de videira ao patógeno, baseada nos componentes epidemiológicos da doença. Os métodos dessecação em papel de filtro (DPF), repicagens periódicas (RP), água destilada esterilizada (ADE) e folhas herborizadas (FH) foramutilizados para preservar dois isolados de Xcv (Xcv1 e Unb1216) durante 12 meses. As variáveis viabilidade e patogenicidade foram avaliadas mensalmente e estimadas pela obtenção de crescimento bacteriano e área abaixo da curva de incidência da doença (AACID). Tanto o método DPF como ADE propiciaram viabilidade constante de 100 % durante 11 meses e os maiores valores de AACID. No método RP não se observou crescimento dos isolados aos 30 dias, enquanto que, em FH, Xcv foi isolada até cinco meses. Os efeitos da temperatura (0, 5, 10, 15, 20, 25, 27, 28, 29, 30, 35, 40 e 45°C), pH (5,0; 5,5; 6,0; 6,5; 7,0; 7,5; 8,0; 8,5 e 9,0) e concentração de NaCl (1, 2, 3, 4, 5, 6 e 7%) sobre o crescimento de dois isolados de Xcv em meio de cultura NYD foram estudados sendo que o crescimento foi avaliado em fotocolorímetro. As temperaturas mínima e máxima para o crescimento de Xcv foram respectivamente 5 e 39°C, enquanto que um crescimento ótimo foi observado no intervalo de 27 a 29°C. Xcv não cresce a 0 e 40°C. A faixa de pH ótima para o crescimento desta bactéria é de7,0 a 7,5. O crescimento de Xcv foi reduzido a partir de 3,0 % de NaCl, sendo o nível de 6,0 % letal para essa bactéria. Para padronizar métodos de quantificação da severidade do cancro bacteriano, foi elaborada uma escala diagramática com níveis de 2, 4, 8, 17, 34, 63 e 91% de área foliar lesionada. Navalidação da escala diagramática, 50 folhas com diferentes níveis de severidade da doença, mensurados previamente com o programa AutoCAD®, foram avaliadas por 10 pessoas sem e com a utilização da escala. Foram realizadas duas avaliações com utilização da escala com intervalo de sete dias, onde seqüências diferentes das mesmas folhas foram estimadas visualmente pelos mesmos avaliadores. A acurácia e a precisão de cada avaliador foram determinadas por regressão linear simples, entre a severidade real e a estimada. Sem a escala, a maioria dos avaliadores superestimou a severidade da doença. Com a escala, os avaliadores obtiveram melhores níveis de acurácia e precisão, embora tendessem a subestimar a severidade com erros absolutos concentrando-se na faixa de 10%. Os avaliadores apresentaram boa repetibilidade e elevada reprodutibilidade das estimativas com utilização da escala, o mesmo não sendo verificado sem a utilização desta. A reação de 20 variedades de videira, sendo 13 de copa e sete de porta-enxerto, foi avaliada quanto à resistência à doença, em casa de vegetação. As plantas foram inoculadas com a suspensão do isolado Xcv1 (A570 = 0,4 correspondente a108 UFC mL-1), incubadas em casa de vegetação e observadas diariamente quanto aos componentes epidemiológicos do cancro bacteriano: período de incubação (PI), incidência de folhas com sintomas (INC), incidência de folhas com cancro (IFC), severidade da doença (SEV), taxa de progresso da incidência da doença (TPID), área abaixo da curva de progresso da severidade da doença (AACPSD). Todas as variedades foram suscetíveis ao patógeno, embora diferindo significativamente entre si (P=0,05) para a maioria das variáveis analisadas. Em geral, ‘Brasil’ apresentou os maiores níveis de doença para todas as variáveis testadas, enquanto ‘Isabel’ e ‘Paulsen 1103’ destacaram-se ao propiciarem os maiores valores de PI e os menores valores de INC, IFC, SEV, TPID e AACPSD, indicando o potencial dessas para utilização em programas de melhoramento genético e de manejo integrado do cancro bacteriano da videira. As variáveis estudadas podem ser utilizadas em pesquisas envolvendo reação de variedades ao cancro bacteriano da videira. Quando considerado o conjunto doscomponenetes epidemiológicos, a análise da distância Euclidiana por UPGMA permitiu a separação das variedades de copa e porta-enxerto em três grupos de similaridade cada.
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ECONOMIC OPERATION OF TYPICAL MICROGRIDSGuo, Yuanzhen 01 January 2018 (has links)
A microgrid is a subnetwork of power system that consists of a group of distributed energy sources and loads. It is designed to integrate distributed generation, loads, energy storage devices, converters, and monitoring and protection devices. Generally, a successful microgrid could run both in island mode (off-grid) and in grid-connected mode (on-grid), being able to convert between two modes at any time. With continuous development of the power system, distributed renewable generation unit accounts for an increasing proportion, since microgrid could effectively connect these generation units to the main grid, thereby improving the energy efficiency and the energy structure. Microgrid is increasingly playing an important role in the power system.
This thesis focuses on reducing the cost of microgrids through economic operation, including both static and dynamic economic operations. Three cases are tested based on these two methods. Also, each case will include four situations including one without ESS and three situations with 2MWh ESS, 3MWh ESS, 4MWh ESS, respectively.
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