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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
181

New markets for Smart Utilities in Western Europe : A framework developed and applied for identification ofmarket opportunities for facilitating strategic decisions

DILAN, REJWANE, Selman, Christos January 2017 (has links)
Digitalization is hitting the energy industry by empowering energy producers and retailers, butmore importantly it’s empowering the end customers and the energy producers and retailers areno longer in possession of all power. Due to digitalization, energy networks are beingmodernized and new emerging technologies called smart grids and smart meters have beenintroduced. Smart grids can automatically monitor energy flows and adjust to changes in energysupply and demand. Smart meters on the other hand empowers the consumers to adapt theirenergy usage in both time and volume to different energy prices throughout the day by costcuttingtheir energy.With empowered and conscious end-customers, electricity retailers will have to compete in newways or risk losing their business. There is a risk that the majority of the over 100 electricityretailers in Sweden will be wiped out with time if data and information is not leveraged to theend-customers. This is potentially also threatening the business of TSU as well as othercompanies providing IT solutions to the energy market.For long Tieto Smart Utility (TSU) has offered IT services for both electricity retailers anddistributors across the Nordics. In relation to recently developed solutions as well as theopportunities and challenges created by digitalization and disruptive technologies such as smartmeters, the Nordic countries are in the forefront. Hence, TSU sees a potential in increasing itspresence in Western Europe to provide services to the retailers and distributors. However, inorder to expand to Western European countries TSU seeks to have a greater marketunderstanding of the different markets, in terms of for example market size, market structure,regulations. The problem is to have a structured and comprehensive way to increase marketunderstanding when assessing new West European energy markets due to the major differencesin each country.This thesis therefore aims to develop a framework which enables IT solution providers toconduct a market opportunity analysis in order to increase market awareness and assess theopportunities and potential in Western European markets, influenced by the smart-meter roll outand thus facilitate strategic decisions.A framework has been developed on the foundation on existing frameworks and applied onTSU by conducting a case study on a market opportunity assessment tool for energy IT solutionproviders. The framework consists of three levels of analysis; European-, Country- andCustomer Level which intends to identify market opportunities and potential.This thesis provides a framework for companies who wants to assess market opportunities andfacilitates strategic decisions regarding the potential of entering the markets. The findings of thisthesis has shown that the market opportunities for TSU are the greatest in Germany especiallydue to the market magnitude as well as the status for the smart meter roll-out. Furthermore,since IT solution providers usually offers many different services and solutions, the findings canbe used in a larger extent in order to asses the potential depending on type service and solution.
182

Economic potential of demand side management based on smart metering of youth hostels in Germany

Kondziella, Hendrik, Retzlaff, Nancy, Bruckner, Thomas, Mielich, Tim, Haase, Christian 12 October 2023 (has links)
Additional electricity meters behind the grid access point can improve understanding of energy consumption patterns and thus, adjust consumption behavior. For this study, smart meters were installed in three hostels, out of which two are analyzed further in this paper. Starting from an onsite inspection, all appliances were assigned to reasonable groups for sub-metering. Based on data for the year 2021, the sites are characterized according to the sub-metering concept. In addition, load profiles for type-days are derived, which allows to establish a baseload during COVID lockdown and compare it to consumption patterns for normal occupation. In the prescriptive part, the demand profiles are analyzed regarding their economic potential for load shifting. Consumption data for one week with normal occupation is used as input for techno-economic modeling. The mixed-integer model minimizes electricity purchasing costs for different scenarios including dynamic tariffs and onsite generation from photovoltaics.
183

Prices in Wholesale Electricity Markets and Demand Response

Aketi, Venkata Sesha Praneeth 02 June 2014 (has links)
No description available.
184

SPECIFICATIONS FOR THE CASSEGRAIN INSTRUMENTS INCLUDING THE CASSEGRAIN OBSERVING PLATFORM, STEWARD OBSERVATORY 90-INCH TELESCOPE

Bok, B. J., Fitch, W. S., Hilliard, R. L., Meinel, Aden B., Taylor, D. J., White, R. E. 02 1900 (has links)
QC 351 A7 no. 16 / This document has been prepared to form the basis for the operational specifications for the Cassegrain instrumentation for the 90-inch telescope of the Steward Observatory. The publication of this document is for the purpose of providing guidance to other astronomical groups who may have use for the considerations recorded herein.
185

Essays on inheritance, small businesses and energy consumption

Escobar, Sebastian January 2017 (has links)
Essay 1: People’s planning to evade the inheritance tax curtails its merits. However, the extent of planning remains a matter of argument. According to popular belief, it is widespread, but few estimates have been presented. This study estimates the extent of estate size under-reporting, a form of inheritance tax planning, using the repeal of the Swedish tax on spousal bequests, in 2004, and a regression discontinuity design. The results show that, on average, estate sizes were 17 percent lower, and the share of estates that completely escaped tax payments was 26 percent larger due to under-reporting. As a consequence, government revenues from the tax were only half of what they would have been without under-reporting. Moreover, preferences and means for under-reporting were not only prevalent among the wealthy, but also among those receiving relatively small inheritances. The study contributes to a growing literature on tax avoidance and evasion by estimating the extent of estate size under-reporting, its effect on government revenues and by showing that it was widespread in the population. / Essay 2: There is an ongoing debate about whether or not inheritance and estate taxes are effective in raising revenues and in contributing to a more equal society. The different views on transfer taxes are largely dependent on beliefs about whether people plan their wealth to avoid these taxes. In this paper, we follow Kopczuk (2007) and study people's planning response to the onset of terminal illness. An extension of Kopczuk’s work is that we can effectively control for responses in wealth caused by terminal illness but unrelated to tax planning. We do this by exploiting a tax reform in Sweden that removed the incentives for people to plan their estates to avoid inheritance taxation. We find some evidence of long-term terminal illness inducing responses consistent with tax planning, but that these are not widespread or efficient enough to reduce the overall tax burden in the study population. Our results, similarly to those of Kopczuk, show that people appear to postpone some decisions about their estates until shortly before death. / Essay 3: Small businesses form an essential part of all economies, making it necessary to understand the conditions under which they operate. This paper contributes to that understanding by studying how survival, income and profits of small businesses change when their owners receive inheritances. Using a difference-in-differences strategy and Swedish registry data on small businesses and estate reports, it is shown that survival rates increase with almost three percentage points when the owners receive inheritances of, on average, SEK 275,000. However, the profits of the surviving small businesses and the income of their owners do not increase, indicating that the inheritance did not increase survival by making investments possible, investments to increase profits and income, but by enabling small business owners of lower ability to subsist. The study contributes to the literature on the conditions for small businesses by providing causal evidence on the effect of increased access to capital among existing businesses. It thereby complements the rich literature on the role of capital for small business start-ups. / Essay 4: This article shows that a simple monetary incentive can dramatically reduce electric energy consumption (EEC) in the residential sector and simultaneously achieve a more desirable allocation of EEC costs. The analyses are based on data from a policy experiment conducted in 2011 and 2012 by a private housing company in about 1,800 apartments. Roughly 800 of the tenants (treatment group) were subject to a change from having unlimited EEC included in their rent to having to pay the market price for their own EEC. This change was achieved by installing EEC meters in each apartment. Tenants in the other 1,000 apartments (control group) experienced no policy change and were subject to apartment-level billing and metering during the entire study period. Using a quasiexperimental research design and daily data on EEC from 2007 to 2015, we estimate that apartment-level billing and metering permanently reduce EEC by about 25%. Moreover, we show that households reduce EEC immediately after being informed that they will be billed for EEC, the reduction is larger when the production cost is higher, and the reduction in EEC comes almost exclusively from households with very high EEC before the policy change. Finally, we show that apartment-level billing and metering are cost-effective, with a cost per reduced kilowatt hour of US$0.01, and for each invested dollar, the social value of reductions in air pollution, including CO2 emissions, is $2.
186

Sistema de monitoramento para estimação de estado harmônico trifásico para sistemas de distribuição utilizando decomposição em valores singulares / Monitoring system for three-phase harmonic state estimation for distribution systems using singular values decomposition

Breda, Jáder Fernando Dias 12 July 2017 (has links)
Este trabalho tem como objetivo o desenvolvimento de uma metodologia de monitoramento a partir da alocação de medidores voltada para a estimação de estado harmônico trifásica em sistemas de distribuição de energia elétrica desequilibrados. O algoritmo de estimação de estado harmônico desenvolvido tem como entrada os fasores de tensão e de corrente em pontos pré-definidos de medição sobre os alimentadores em análise. Para a alocação dos medidores, verificou-se a necessidade de a mesma ser realizada e direcionada para este problema, e um algoritmo de otimização em específico foi desenvolvido utilizando algoritmos genéticos. Para a estimação de estado harmônico, a técnica de Decomposição em Valores Singulares foi utilizada, por ser adequada a sistemas não completamente observáveis. Em relação às simulações, cargas não lineares (ou perturbadoras) foram conectadas ao longo dos alimentadores testes do IEEE de 13, 34 e 37 barras, considerando configuração trifásica assimétrica para as linhas e cargas desbalanceadas. Todas as simulações computacionais foram realizadas dispondo do programa DIgSILENT PowerFactory. Os resultados satisfatórios encontrados denotam que o desempenho do estimador desenvolvido é dependente dos pontos de medição pré-definidos a partir da alocação dos medidores realizada. Pela metodologia implementada e aplicada, o algoritmo de estimação de estado harmônico veio a corretamente calcular todas as variáveis de estado e, consequentemente, os sistemas testes em análise tornaram-se completamente observáveis para todas as fases e ordens harmônicas caracterizadas. / This research aims for the development of a monitoring methodology through the allo-cation of meters in order to perform a three-phase harmonic state estimation in unbalanced distribution systems. The harmonic state estimation algorithm developed has voltage and current phasors as inputs at predefined measurement points on the feeders about analysis. For an allocation of the meters, there was a need for it to be performed and directed to this problem, and a specific optimization algorithm was developed using Genetic Algorithms. For a harmonic state estimation, the Singular Value Decomposition technique was made, because it is suitable for systems that are not completely observable. Regarding the simulations, the non-linear (or disturbing) loads were connected along the test feeders of the IEEE of 13, 34 and 37 bus, considering the three-phase asymmetric configuration for lines and loads. All computational simulations were performed in the DIgSILENT PowerFactory software. The satisfactory results found note that the performance of the developed estimator depends on the pre-defined measurement points from the allocation of the realized meters. By the applied methodology, the harmonic state estimation algorithm came to correctly calculate all the state variables and, consequently, the test systems about analysis became fully observable for all phases and harmonic orders characterized.
187

Metodologia baseada em medidas dispersas de tensão e árvores de decisão para localização de faltas em sistemas de distribuição modernos / Methodology based on dispersed voltage measures and decision trees for fault location in modern distribution systems

Araújo, Marcel Ayres de 06 October 2017 (has links)
Nos sistemas de distribuição, a grande ramificação, radialidade, heterogeneidade, dinâmica das cargas e demais particularidades, impõem dificuldades à localização de faltas, representando um desafio permanente na busca por melhores indicadores de continuidade e confiabilidade no fornecimento de energia elétrica. A regulação incisiva dos órgãos do setor, a penetração de geração distribuída e a tendência de modernização trazida pelas redes inteligentes, demandam detalhados estudos para readequação dos sistemas elétricos a conjuntura atual. Neste contexto, esta tese propõe o desenvolvimento de uma metodologia para localização de faltas em sistemas de distribuição empregando a capacidade dos medidores inteligentes de monitoramento e de aquisição de tensão em diferentes pontos da rede elétrica. A abordagem proposta baseia-se na estimação, por ferramentas de aprendizado de máquina, das impedâncias de sequência zero e positiva entre os pontos de alocação dos medidores inteligentes e de ocorrência de falta, e do estado de sensibilização destes medidores frente a correntes de falta. Assim, calculando-se as respectivas distâncias elétricas em função das impedâncias estimadas e definidas as direções das mesmas em relação a topologia da rede, busca-se identificar o ponto ou área com maior sobreposição de distâncias elétricas como o local ou a região de maior probabilidade da falta em relação aos medidores inteligentes. Para tanto, faz-se uso combinado de ferramentas convencionais e inteligentes pela aplicação dos conceitos de análise de sistemas elétricos, diagnóstico dos desvios de tensão, e classificação de padrões por meio da técnica de aprendizado de máquina denominada Árvore de Decisão. Os resultados obtidos pela aplicação desta metodologia demonstram que o uso de informações redundantes fornecidas pelos medidores inteligentes minimiza os erros de estimação. Além disso, para a maior parte dos casos testados o erro absoluto máximo de localização da falta se concentra entre 200 m e 1000 m, o que reduz a busca pelo local de ocorrência da falta pelas equipes de manutenção da rede elétrica. / In distribution systems, the dense branching, radial pattern, heterogeneity, dynamic of the loads, and other characteristics create several difficulties in defining the fault location, representing a great challenge in the search for better continuity and reliability indicators of the electrical energy supply. The intense government regulations, the increasing use of distributed generation, and the trend towards modernization via smart grids require a detailed study in order to upgrade the current systems. In this context, this thesis proposes a methodology development for fault location in distribution systems with the use of smart meters monitors and the acquisition of voltage at different points in the electrical network. The proposed method is based on the estimation, using machine learning, of the state of awareness of smart meters across the fault currents and of the zero and positive sequence impedance between the location of these meters and of the fault occurrence. Therefore, by calculating the electrical distances as a function of the estimated impedances and defining its the direction in relation to the network topology, the point/region with the biggest superposition of the electrical distances can be assigned as the point/region with the highest probability of fault occurrence in relation to the smart probes. For this purpose, a machine learning technique named decision tree is used to apply concept analyses to the electrical systems, diagnosis of voltage deviations, and pattern recognition of the electrical systems. The results obtained by the application of this methodology demonstrate that the use of redundant information provided by the smart meters minimizes estimation errors. In addition, for most of the cases tested, the maximum absolute error of the fault location is concentrated between 200 m and 1000 m, which reduces the search for the fault location by the maintenance teams of the electrical network.
188

Nitrogênio e tipos de substratos no monitoramento nutricional, na produtividade e na qualidade do tomateiro cultivado em ambiente protegido climatizado / Nitrogen and substrate in nutritional management, yield and quality of tomato growth in climated greenhouse

Campagnol, Rafael 12 February 2015 (has links)
A produção de hortaliças em substratos é uma técnica de cultivo que pode aumentar a produtividade, economizar recursos e facilitar o manejo nutricional das plantas. Contudo, para que isso seja possível, deve-se conhecer os fatores que afetam o crescimento das plantas cultivadas nesse sistema. O objetivo deste trabalho foi avaliar os efeitos de diferentes doses de nitrogênio da solução nutritiva (SN) (60, 80 100, 120 e 140% da dose padrão) em dois tipos de substratos (S1: fibra de coco e S2: a base de casca de pinus) no cultivo de minitomate Sweet Grape. Foram avaliadas ao longo do ciclo de cultivo o pH, a condutividade elétrica (CE) e o teor de nitrato (NO3-drenado) e potássio (K+drenado) na solução drenada dos vasos, o índice SPAD e o teor de nitrato (NO3- pecíolo) e potássio (K+ pecíolo) da seiva do pecíolo das folhas e o teor de nitrogênio da massa seca das folhas (Nfolha). Foram determinados o número de cacho por planta (NCPP) e o comprimento médio das hastes (CMH). Os frutos colhidos foram classificados, contados e pesados para a obtenção da massa média dos frutos grandes (MMFG), médios (MMFM) e pequenos (MMFP), massa total de frutos por planta (MTFPP), massa total de frutos grandes (MTFG), médios (MTFM), pequenos (MTFP) e rachados (MTFRA), número total de frutos por planta (NTFPP), número total de frutos grandes (NTFG), médios (NTFM), pequenos (NTFP) e rachados (NTFRA). Amostras de frutos foram coletadas em três períodos e avaliadas quanto ao teor de sólidos solúveis (TSS), acidez titulável (AT) e concentração de ácido ascórbico (AA). Os valores de pHdrenado diminuíram com o aumento das doses de N da solução nutritiva. Os efeitos do N no pHdrenado se intensificaram ao longo do ciclo de cultivo em razão do acúmulo de sais no meio radicular, principalmente no S1. A CEdrenada aumentou com dose de N e foi maior no S2. O aumento da dose de N elevou os teores de NO3-drenado em ambos os substratos. O K+drenado foi superior na dose de 140% de N no S1. Os valores de índice SPAD e Nfolha aumentaram com a elevação das doses de N da solução nutritiva e reduziram ao longo do ciclo de cultivo. O NO3-pecíolo elevou com o aumento da dose de N da SN. A MMFG foi superior com a adição de 140% de N em relação à dose de 60%. O aumento da dose de N elevou o NTFG, NTFM, NTFP, NTRA e NTFPP. O maior NTFG foi obtido no S2 enquanto que o maior NTFPP, NTFP e NTFRA ocorreu no S1. A MTFG, MTFM, MTFP, MTFRA e MTFPP aumentaram com o aumento da dose de N. Os valores mais elevados de MTFG e MTFP foram obtidos na dose de 140% de N, 331,05 e 1.249,82 g planta-1, respectivamente. A maior MTFM foi obtida na dose de 120% de N, não diferindo, porém, das doses de 100 e 140% de N. O TSS, a AT e o AA dos frutos não foram influenciados pelas doses de N e tipos de substrato. / Vegetables production in soilless media is a technique that can increase yield, saving resources and facilitate the nutritional management of plants. However, for that to be possible, its necessary to know how the factors affect the plants growth in this system. The aim of this study was to evaluate the effects of different nitrogen rates of nutrient solution (NS) (60, 80 100, 120 and 140% of the standard) in two type of soilless media (S1: coconut fiber and S2: pine bark as base) for the mini tomato Sweet Grape growth. Were evaluated during the growing season pH, electrical conductivity (EC) and the nitrate content (NO3-drained) and potassium (K+ drained) in the solution drained from the vessels, SPAD index and the nitrate (NO3-pecíolo) and potassium (K+ petiole) content on petiole sap from the leaves and the nitrogen content in leaf dry mater (Nleaf). Were determined the number of fruit per plant (NFPP) and the average length of stems (ALS). The harvested fruits were sorted, counted and weighed to obtain the average mass of large fruits (AMLF), medium fruits (AMMF) and small fruits (AMSF), total weight of fruits per plant (TWFPP), total weight of large fruits (TWLF) medium fruits (TWMF), small fruits (TWSF) and cracked fruits (TWCF), total number of fruits per plant (TNFPP), total number of large fruits (TNLF), medium fruits (TNMF), small frutis (TNSF) and cracked fruits (TNCF). Fruit samples were collected in three periods and evaluated for soluble solids (SS), titratable acidity (TA) and concentration of ascorbic acid (AA). The pHdrained values decreased with increasing N levels in nutrient solution. The effects of N on pHdrained intensified throughout the growing season due to the accumulation of salts in the root medium, especially in S1. The CEdrained increased with N rate and was higher in S2. The increase in N rate increased the levels of NO3-drained on both substrates. The K+ drained was higher at 140% N dose in S1. SPAD index and Nleaf values increased with higher N rates in nutrient solution and reduced throughout the growing season. The NO3 - petiole increased with increasing dose of N in NS. The MMFG was higher with the addition of 140% N in relation to the dose of 60%. The increase in N rate increased the TNLF, TNMF, TNSF, TNCF and TNFPP. The biggest TNLF was obtained in S2 while the largest TNFPP, TNSF and TNCF occurred in S1. The TWLF, TWMF, TWSF, TWCF and TWFPP increased with increasing N levels in NS. The highest values of TWLF and TWSF were obtained at 140% N level, 331.05 and 1249.82 g plant-1, respectively. The biggest TWMF was obtained at 120% N level in NS, however, not differing of the 100 and 140% N levels. The SS, TA and AA fruits were not influenced by N and substrate types.
189

Análise comparativa de medidor de vazão em flare por tecnologia ótica e pitometria utilizando túnel de vento

Silva, Felipe Carvalho da 25 July 2012 (has links)
Made available in DSpace on 2016-12-23T14:08:09Z (GMT). No. of bitstreams: 1 Felipe Carvalho da Silva.pdf: 4181457 bytes, checksum: 8aef395272a667525a72d34c5ffb865f (MD5) Previous issue date: 2012-07-25 / With recent discoveries by the oil industry related to the reserves in Brazilian pre-salt, flow measurement technology is being re-evaluated in view of the large CO2 concentrations found in these reserves. A technology that has accuracy levels similar to those obtained with flow meters currently used and also measures independent characteristics to the composition and thermodynamic properties of gases is optical flow measurement velocimetry (OFM). The present work is related to experimental study, comparison of the speed readings from Pitot tube flow meters and optical velocimetry. This experimental study consists of qualifying and quantifying the velocity profiles among the possible configurations of flow in the wind tunnel, proposing methodology using flow conditioners and damping of the readings obtained with the Pitot tube, and analysis of readings taken with the optical sensor to evaluate the device installation effects in the results. The results indicate that transit-time optical flow meters for medium to high speed levels, could provide readcohesive flow even in a misalignment of up to ± 5 °, although it appears in the installation manual of the manufacturer guarantees of results meter when a misalignment of at most up to ±2º. Regarding the optical sensor intrusive effect in the readings simultaneous with the Pitot tube, it is perceived, in general, from approximately Re> 2,05x105, the intrusive effect of this influence is suppressed by other effects. Finally, for a proper flow study through Pitometry in order to make the comparison with the optical flow metering and achieve satisfactory results with the Pitot tube, the use of specific devices of flow conditioning and damping of the measured values had to be made / Com as recentes descobertas da indústria petrolífera brasileira, relacionadas às reservas no pré-sal, a tecnologia de medição de vazão está sendo reavaliada, tendo em vista as grandes concentrações de CO2 encontradas nessas reservas. A tecnologia de medição de vazão por velocimetria óptica (OFM) possui níveis de precisão semelhantes aos obtidos com os medidores de vazão utilizados atualmente. Essa tecnologia possui as características de independência com relação à composição química e às propriedades termodinâmicas dos gases. O presente trabalho se dedica ao estudo experimental de comparação das leituras de velocidade entre tubo de Pitot e medidor de vazão por velocimetria óptica. Para isso foi efetuada qualificação e quantificação dos perfis de velocidades em escoamento no túnel de vento, propondo metodologia de uso de retificadores de fluxo e amortecimento das leituras obtidas com o tubo de Pitot, e análises de leituras realizadas com o sensor óptico visando avaliar os efeitos de instalação do dispositivo nos resultados obtidos. Os resultados indicam que medidores de vazão ópticos por tempo de trânsito, para níveis médios e altos de velocidade, podem fornecer a leitura esperada da vazão mesmo estando num desalinhamento de ±5º, apesar de constar no manual de instalação do fabricante garantia destes resultados do medidor quando num desalinhamento de, no máximo, até ±2º. Com relação ao efeito intrusivo do sensor óptico nas leituras simultâneas com o tubo de Pitot, percebe-se, em geral, que a partir de aproximadamente Re> 2,05x105, o efeito intrusivo desta influência foi suprimido por outros efeitos. Por fim, para uma devida caracterização do escoamento por meio de pitometria, a fim de efetuar a comparação com a medição Laser, e alcançar satisfatórios resultados com o tubo de Pitot, foi necessário fazer uso de dispositivos específicos como retificadores de fluxo e de amortecimento (damping) dos valores medidos
190

Nitrogênio e tipos de substratos no monitoramento nutricional, na produtividade e na qualidade do tomateiro cultivado em ambiente protegido climatizado / Nitrogen and substrate in nutritional management, yield and quality of tomato growth in climated greenhouse

Rafael Campagnol 12 February 2015 (has links)
A produção de hortaliças em substratos é uma técnica de cultivo que pode aumentar a produtividade, economizar recursos e facilitar o manejo nutricional das plantas. Contudo, para que isso seja possível, deve-se conhecer os fatores que afetam o crescimento das plantas cultivadas nesse sistema. O objetivo deste trabalho foi avaliar os efeitos de diferentes doses de nitrogênio da solução nutritiva (SN) (60, 80 100, 120 e 140% da dose padrão) em dois tipos de substratos (S1: fibra de coco e S2: a base de casca de pinus) no cultivo de minitomate Sweet Grape. Foram avaliadas ao longo do ciclo de cultivo o pH, a condutividade elétrica (CE) e o teor de nitrato (NO3-drenado) e potássio (K+drenado) na solução drenada dos vasos, o índice SPAD e o teor de nitrato (NO3- pecíolo) e potássio (K+ pecíolo) da seiva do pecíolo das folhas e o teor de nitrogênio da massa seca das folhas (Nfolha). Foram determinados o número de cacho por planta (NCPP) e o comprimento médio das hastes (CMH). Os frutos colhidos foram classificados, contados e pesados para a obtenção da massa média dos frutos grandes (MMFG), médios (MMFM) e pequenos (MMFP), massa total de frutos por planta (MTFPP), massa total de frutos grandes (MTFG), médios (MTFM), pequenos (MTFP) e rachados (MTFRA), número total de frutos por planta (NTFPP), número total de frutos grandes (NTFG), médios (NTFM), pequenos (NTFP) e rachados (NTFRA). Amostras de frutos foram coletadas em três períodos e avaliadas quanto ao teor de sólidos solúveis (TSS), acidez titulável (AT) e concentração de ácido ascórbico (AA). Os valores de pHdrenado diminuíram com o aumento das doses de N da solução nutritiva. Os efeitos do N no pHdrenado se intensificaram ao longo do ciclo de cultivo em razão do acúmulo de sais no meio radicular, principalmente no S1. A CEdrenada aumentou com dose de N e foi maior no S2. O aumento da dose de N elevou os teores de NO3-drenado em ambos os substratos. O K+drenado foi superior na dose de 140% de N no S1. Os valores de índice SPAD e Nfolha aumentaram com a elevação das doses de N da solução nutritiva e reduziram ao longo do ciclo de cultivo. O NO3-pecíolo elevou com o aumento da dose de N da SN. A MMFG foi superior com a adição de 140% de N em relação à dose de 60%. O aumento da dose de N elevou o NTFG, NTFM, NTFP, NTRA e NTFPP. O maior NTFG foi obtido no S2 enquanto que o maior NTFPP, NTFP e NTFRA ocorreu no S1. A MTFG, MTFM, MTFP, MTFRA e MTFPP aumentaram com o aumento da dose de N. Os valores mais elevados de MTFG e MTFP foram obtidos na dose de 140% de N, 331,05 e 1.249,82 g planta-1, respectivamente. A maior MTFM foi obtida na dose de 120% de N, não diferindo, porém, das doses de 100 e 140% de N. O TSS, a AT e o AA dos frutos não foram influenciados pelas doses de N e tipos de substrato. / Vegetables production in soilless media is a technique that can increase yield, saving resources and facilitate the nutritional management of plants. However, for that to be possible, its necessary to know how the factors affect the plants growth in this system. The aim of this study was to evaluate the effects of different nitrogen rates of nutrient solution (NS) (60, 80 100, 120 and 140% of the standard) in two type of soilless media (S1: coconut fiber and S2: pine bark as base) for the mini tomato Sweet Grape growth. Were evaluated during the growing season pH, electrical conductivity (EC) and the nitrate content (NO3-drained) and potassium (K+ drained) in the solution drained from the vessels, SPAD index and the nitrate (NO3-pecíolo) and potassium (K+ petiole) content on petiole sap from the leaves and the nitrogen content in leaf dry mater (Nleaf). Were determined the number of fruit per plant (NFPP) and the average length of stems (ALS). The harvested fruits were sorted, counted and weighed to obtain the average mass of large fruits (AMLF), medium fruits (AMMF) and small fruits (AMSF), total weight of fruits per plant (TWFPP), total weight of large fruits (TWLF) medium fruits (TWMF), small fruits (TWSF) and cracked fruits (TWCF), total number of fruits per plant (TNFPP), total number of large fruits (TNLF), medium fruits (TNMF), small frutis (TNSF) and cracked fruits (TNCF). Fruit samples were collected in three periods and evaluated for soluble solids (SS), titratable acidity (TA) and concentration of ascorbic acid (AA). The pHdrained values decreased with increasing N levels in nutrient solution. The effects of N on pHdrained intensified throughout the growing season due to the accumulation of salts in the root medium, especially in S1. The CEdrained increased with N rate and was higher in S2. The increase in N rate increased the levels of NO3-drained on both substrates. The K+ drained was higher at 140% N dose in S1. SPAD index and Nleaf values increased with higher N rates in nutrient solution and reduced throughout the growing season. The NO3 - petiole increased with increasing dose of N in NS. The MMFG was higher with the addition of 140% N in relation to the dose of 60%. The increase in N rate increased the TNLF, TNMF, TNSF, TNCF and TNFPP. The biggest TNLF was obtained in S2 while the largest TNFPP, TNSF and TNCF occurred in S1. The TWLF, TWMF, TWSF, TWCF and TWFPP increased with increasing N levels in NS. The highest values of TWLF and TWSF were obtained at 140% N level, 331.05 and 1249.82 g plant-1, respectively. The biggest TWMF was obtained at 120% N level in NS, however, not differing of the 100 and 140% N levels. The SS, TA and AA fruits were not influenced by N and substrate types.

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