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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.
91

Avaliação de parâmetros de desempenho de rede de sensores sem fio em casa de vegetação para cultivo hidropônico de morangos / Evaluation of performance parameters for wireless sensor network in a greenhouse for hydroponic cultivation of strawberries

Alves, Elaine Cangussú de Souza 09 August 2011 (has links)
Orientador: Bárbara Janet Teruel Mederos / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-19T15:41:33Z (GMT). No. of bitstreams: 1 Alves_ElaineCangussudeSouza_M.pdf: 1610597 bytes, checksum: 9136ba250ed9462c6fbb4d8204f73a4a (MD5) Previous issue date: 2011 / Resumo: Este trabalho tem como objetivo coletar dados de qualidade de sinal transmitido entre uma estação base e um nó sensor localizado no interior de uma casa de vegetação, localizada no campo experimental da Faculdade de Engenharia Agrícola - UNICAMP, com o auxilio de ferramentas computacionais. No interior da casa de vegetação foi inserido um sistema hidropônico com bancadas que forneciam suporte para morangueiros da cultivar Albion. O conjunto de equipamentos e de nós sensores que foram utilizados para montar a rede é da marca Crossbow®. Após a implantação do nó sensor foram realizados experimentos com o objetivo de verificar alcance e qualidade do sinal de acordo com sua potência. Através desses ensaios foi possível concluir que uma Potência de Sinal com valor de -12,2 dBm seria suficiente para manter a transmissão entre Estação Base e Nó Sensor. Testes também foram realizados para uma Potência de Sinal de -9,2 dBm, e mostraram que a rede possuía qualidade classificada como "muito alta". Porém, através do teste de duração da bateria, nota-se que existe uma economia de energia ao utilizar a Potência de Sinal de -12,2 dBm. No geral, foi demonstrado que o valor da Potência de Sinal tem influência sobre a qualidade do sinal de transmissão e recepção, o gasto de bateria e o alcance do sinal. Assim, este é um importante parâmetro a ser considerado em um projeto de implantação de rede de sensores sem fio no meio agrícola / Abstract: This project aims to collect quality data signals transmitted between a base station and a sensor node located inside a greenhouse, which is a experimental field located in the College of Agricultural Engineering - UNICAMP, with help of computational tools. Inside the greenhouse, a hydroponic system with banks providing support for strawberry Albion was inserted. The set of sensor nodes and equipment that were used to assemble the network is the Crossbow® brand. After sensor node deployment, experiments were performed in order to check range and signal quality. Through these experiments, it was concluded that a RF power value of -12.2 dBm is sufficient to maintain transmissions between base station and the sensor. Tests were also performed to a RF power of -9.2 dBm, and showed that the network had quality rated as "very high". However, by testing the battery life, it is noted that there is an energy saving when the RF power of -12.2 dBm is used. Overall, it was shown that the value of the signal strength has an influence on the quality of signal transmission and reception, battery depletion and signal range. So, this is an important parameter to be considered in a project to establish network of wireless sensors in a agricultural environment / Mestrado / Maquinas Agricolas / Mestre em Engenharia Agrícola
92

Produção e qualidade de mudas de morangueiro com diferentes concentrações de nitrogênio em cultivo sem solo / Production and quality of strawberry transplants under different nitrogen concentration of the nutrient solution

Oliveira, Clarisse Silva 28 August 2009 (has links)
The objective of this study was to evaluate the effect of nitrogen concentration on the production and quality of strawberry bare root transplants and runner tips in a soilless growing system using sand as substrate. Stock plants were planted on September 13th, 2007. Transplants were harvested on February 18th, 2008. Treatments were nitrogen concentrations in the nutrient solution of 8, 11, 14 and 17 mmol L-1. The experiment was a completely randomized design with three replications of 3.6m2 plots. Number and crown diameter of bare root transplants and number of runner tips were evaluated at harvesting. Number of bare root transplants and runner tips was not affected by N concentration in the nutrient solution. An average of 339 bare root transplants and 836 runner tips were harvest per stock plant. Crown diameter of bare root transplants decreased linearly with the increase in N concentration of the nutrient solution. It was concluded that in this soilless cropping system the increase in N concentration in the nutrient solution does not affect the number of strawberry bare root transplants and runner tips, but the crown diameter of bare root transplants is reduced. The N concentration of 8 mmol L-1 may be used for crop propagation in this growing system. / O objetivo do trabalho foi avaliar o efeito da concentração de nitrogênio na produção e na qualidade de mudas de raízes nuas e pontas de estolões de morangueiro no cultivo sem solo empregando areia como substrato. O plantio das matrizes foi realizado em 13 de setembro de 2007 e a colheita das mudas em 18 de fevereiro de 2008. Os tratamentos foram quatro concentrações de N na solução nutritiva de 8, 11, 14 e 17 mmol L-1. O delineamento utilizado foi o inteiramente casualizado, com três repetições de 3,6m2. No momento da colheita foi determinado o número e o diâmetro da coroa das mudas de raízes nuas e o número de pontas de estolões. As concentrações de N não afetaram o número de mudas e de pontas de estolões, cujas médias foram de 339 e 836, respectivamente. O diâmetro da coroa das mudas de raízes nuas diminuiu linearmente com o aumento da concentração de N. Concluiu-se que o aumento da concentração de N na solução nutritiva nesse sistema de cultivo sem solo não afeta o número de mudas de raízes nuas e nem de pontas de estolões, mas reduz o diâmetro da coroa das mudas de raízes nuas de morangueiro. A concentração de 8 mmol.L-1 de N pode ser empregada para fins de produção de mudas nesse sistema.
93

Produção e composição bromatologica da forragem hidropônica de trigo / Production and bromatoligal composition in hidroponic wheat forage

Medeiros, Liziany Müller 09 February 2006 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Hydroponics forage is an alternative to producers who need quality food to their animals, at times of the year with low demand. It was carried out two experiments inside a polyethylene greenhouse (tunnel), in the Ecophysiology and Hydroponic Research Center (NUPECH), of the Federal University of Santa Maria, Brazil. The objective this work was to evaluate the production and bromatological nutrition in hidropoinc wheat forage. The experimental design was randomized complete block in a 2x4 factorial scheme, consisted of two nutrient solutions and four harvesting dates (4, 8, 12 and 16 days after emergence). In the firts experiment, it was evaluated two inorganic nutrient solution: SNN- NEVES (2001) solution and SNS- SANTOS et al. (2004) solution, and nitrate content was determined in wheat forage. In second experiment, the nutrients solutions evaluated were: SNS inorganic nutritive solution according to SANTOS et al., (2004) s recommendation, SNSC organic nutritive solution partly corrected attending SANTOS et al., (2004) s recommendation. It was not observed interaction (P 0.05) between sowing densities and harvest date for the variables dry mat ter (DM), crude protein (CP), soluble protein (SP), acid detergent fiber content (ADF), neutral detergent fiber content (NDF), lignine (LIG) and in vitro digestibility of dry matter (IVDDM). The hydroponic wheat forage cultivated with the SNS solution presented higher dry mass production and lower neutral detergent fiber content. It was observed decrease in dry matter production and digestibility in vitro and increase in nitrate content when delaying the harvesting dates. In the second experiment, it was observed interaction (P< 0.05) between nutrients solutions and harvest date for DM, CP, SP and NDF. The variables one presented square regression in relation to increase in harvest date, with positve response in DM and negative in CP, SP and NDF, for SNS and SNSC nutrient solution. It was observed increase in ADF and LIG and decrease in IVDDM content when delaying the harvesting dates. The superior value of IVDDM was obtained in forage produced with SNS solution in relation SNSC. The of ADF and LIG substance did not presented significant difference (P<0.05) among the SNS and SNSC solutions. The organic solution of bovine vermicompost besides offering the hydroponics forage production of good nutritional quality of wheat, it allows the use of residue produced in property, decreasing the production cost of nutritive solution. In the experiments, the best bromatolical characteristics of hydroponic wheat forage were verified with harvest at 8 - 12 days after sowing. / A utilização da forragem hidropônica é uma opção para atender às dificuldades de produção de pecuaristas, que não dispõem de quantidade e qualidade nutricional nos alimentos, a serem ofertados para animais em épocas do ano com baixa demanda. Neste sentido, foram conduzidos dois experimentos em ambiente protegido (túnel alto), na Universidade Federal de Santa Maria (UFSM) RS, no ano 2004. O trabalho objetivou avaliar a produção e qualidade nutricional da forragem hidropônica de trigo, cultivada com diferentes soluções nutritivas identificando a idade ideal de colheita. O delineamento experimental utilizado foi blocos ao acaso, distribuído em esquema fatorial 2x4, constituído por duas soluções e quatro idades de colheita (4, 8, 12 e 16 dias após a semeadura). No primeiro experimento as soluções avaliadas foram inorgânicas: SNN- solução descrita por NEVES (2001) e SNS- solução proposta por SANTOS et al., (2004), procedendo-se a analise do nitrato. No segundo experimento, as soluções nutritivas foram uma inorgânica, SNSsolução SANTOS et al., (2004), e a outra orgânica (vermicomposto bovino) parcialmente corrigida para atender recomendação de SANTOS et al., (2004). A interação entre soluções nutritivas (SNN e SNS) e idades de colheita não foi significativa (P 0,05) para as variáveis fitomassa seca (FS), proteína bruta (PB), proteína solúvel (PS), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA), lignina (LIG) e digestibilidade in vitro da fitomassa seca (DIVFS). A forragem hidropônica de trigo cultivada com a solução SNS apresentou maior produção de FS e menor teor de FDN. O aumento no intervalo de tempo da idade de colheita proporcionou redução na produção de FS e na DIVFS e aumento no teor de nitrato. No segundo experimento, foi observada significância (P<0,05) entre a interação das soluções nutritivas (SNS e SNSC) e idades de colheita para as variáveis: FS, PB, PS e FDN. As variáveis ajustaram-se a equação de regressão quadrática em função da idade de colheita, sendo positiva para FS e negativa para PB, PS e FDN, tanto para a SNS quanto SNSC. O aumento no intervalo de tempo da idade de colheita na produção de forragem hidropônica determinou incremento linear no teor de FDA e LIG, e diminuição linear da DIVFS. A forragem cultivada com SNS apresentou teor superior DIVFS em relação à SNSC. O teor de FDA e LIG não apresentou diferença significativa (P>0,05) entre as soluções. A solução orgânica de vermicomposto bovino proporcionou a produção de forragem hidropônica de trigo de boa qualidade nutricional. Nos experimentos, concluiu-se que a colheita seja realizada entre 8 - 12 dias, principalmente devido aos bons teores protéicos sem o comprometimento do menor teor de FS e de sua digestibilidade.
94

The water and nutrient potential of brewery effluent for hydroponic tomato production

Power, Sean Duncan January 2014 (has links)
Brewery effluent that had undergone treatment in an anaerobic digester (AD) was used as an alternative water and nutrient source for hydroponic crop production. Brewery effluent was demonstrated to contain sufficient nutrients to support the growth, flowering and fruiting of Lycopersicum escolentum "Moneymaker" tomato crops. The adjustment of the effluent pH with phosphoric acid to between pH 6.0 and 6.5 increased the development of the crops by around 100% compared to crops grown in unaltered effluent. The pH adjusted effluent-grown plants grew to a mean height of 831.4 ± 21.1 mm and a dry biomass weight of 42.34 ± 2.76 g compared to the unaltered pH effluent plants which grew to a height of 410.6 ± 20.5 mm and a weight of 7.65 ± 0.68 g after 49 days. Effluent treatment in high-rate algal ponds (HRAP) was determined to have no positive effect on the nutritional potential of the effluent for Moneymaker production. The effluent-grown plants did not perform as well as plants grown in inorganic-fertilizer and municipal water. Plants grown in effluent grew taller but did not produce significantly more fruit when phosphoric acid (height: 1573.3 ± 50.4 mm, 19.4 ± 1.4 fruit per plant) was compared to nitric acid (height: 1254.1 ± 25.4 mm, 15.6 ± 1.5 fruit per plant) as the pH adjustment over 72 days. Direct and secondary plant stresses from effluent alkalinity, ammonium nutrition, nitrogen limitation, sodium concentrations and heat stress among other factors were probably confounding variables in these trials and require further investigation. Considering the raw effluent composition and manipulating the AD operation is a potential opportunity to improve overall AD performance, reduce chemical inputs in the effluent treatment process, reduce the final effluent alkalinity, and increase available nitrogen content in the final effluent. The anaerobic digester discharging >1000 m³ of nutrient enriched effluent every day is a resource with considerable potential. The benefits of developing this resource can contribute to cost-reduction at the brewery, more efficient water, nutrient and energy management at the brewery, and offer opportunities for job creation and potentially benefit local food security.
95

Hidrosical: software para cálculo de solução nutritiva em sistema hidropônico NFT. / The technology company is present in virtually all areas of science as a productivity tool , assisting professionals in these areas in their daily work . In agriculture it could not be otherwise , because the computer should be an ally and should seek to assist the farmer in increasing productivity and maximizing product quality . Thus the objective is to research develop software for calculating nutrient solution for hydroponic NFT system . The study was conducted in the premises of the University of Alfenas , Câmpus Alfenas - MG . For the development of this software as HTML and JavaScript technologies for development of the program interface , MySql database were used . This program allows the farmer to register his property and personnel records , records of the products being used , calculating the solution and reports the results of calculations of the products used in the preparation of the hydroponic solution . Keywords : hydroponics , NFT system , MySQL. Hidrosical : Software for calculation of nutrient solution in hydroponic system nft.

Luz, Francisco Donizeti Vieira 06 June 2014 (has links)
Made available in DSpace on 2016-05-02T13:53:56Z (GMT). No. of bitstreams: 1 Francisco Donizeti Vieira Luz-dissertacao.pdf: 2913125 bytes, checksum: 9c47c70e9d5e721e289cc79e063dcedf (MD5) Previous issue date: 2014-06-06 / The technology company is present in virtually all areas of science as a productivity tool , assisting professionals in these areas in their daily work . In agriculture it could not be otherwise , because the computer should be an ally and should seek to assist the farmer in increasing productivity and maximizing product quality . Thus the objective is to research develop software for calculating nutrient solution for hydroponic NFT system . The study was conducted in the premises of the University of Alfenas , Câmpus Alfenas - MG . For the development of this software as HTML and JavaScript technologies for development of the program interface , MySql database were used . This program allows the farmer to register his property and personnel records , records of the products being used , calculating the solution and reports the results of calculations of the products used in the preparation of the hydroponic solution . / A tecnologia da Informação está presente em praticamente todas as áreas das ciências como ferramenta de produtividade, auxiliando os profissionais dessas áreas em seus trabalhos diários. Na agricultura, isso não poderia ser diferente, pois a informática deve ser uma aliada e deve buscar auxiliar o produtor agrícola no aumento de sua produtividade bem como na maximização na qualidade dos produtos. Sendo assim, objetivou-se com a pesquisa desenvolver software para cálculo de solução nutritiva para o sistema hidropônico NFT. O trabalho foi desenvolvido nas dependências da Universidade de Alfenas, Câmpus de Alfenas MG. Para o desenvolvimento desse software, foram utilizadas as tecnologias JavaScript e HTML para desenvolvimento da interface do programa, banco de dados MySql. Esse programa permite ao produtor agrícola o cadastro de sua propriedade bem como o cadastro pessoal, o cadastro dos produtos a serem utilizado, o cálculo da solução e os relatórios do resultado dos cálculos referentes aos produtos utilizados na preparação da solução hidropônica.
96

Óxido nítrico como agente amenizador do estresse salino em alface semi-hidropônica /

Marques, Isabelly Cristina da Silva January 2020 (has links)
Orientador: João Domingos Rodrigues / Resumo: Perante a atual demanda hídrica para manutenção de cultivos intensos e sucessivos, faz-se necessária a busca de alternativas para o manejo correto da água a fim de reduzir seu desperdício. Uma dessas alternativas se concentra na utilização de águas de qualidade inferior como, por exemplo, águas salobras. No entanto, uso de águas salobras podem ocasionar diversas alterações no metabolismo das plantas, necessitando de estratégias que permitam o uso dessas águas. Na busca dessas alternativas, busca-se substâncias biológicas ou sintéticas que gerem respostas fisiológicas e bioquímicas que promovam a adaptação das plantas às condições ambientais adversas, a exemplo do óxido nítrico (NO). Partindo desse pressuposto, objetivou-se com este trabalho avaliar o efeito atenuante do óxido nítrico em plantas de alface crespa, cv. Vera, cultivada sob estresse salino. O experimento foi realizado em casa de vegetação nos meses de abril e maio de 2019, da Fazenda Experimental de São Manuel da FCA, localizada no município de São Manuel/SP. O delineamento experimental adotado foi o de blocos ao acaso, em esquema fatorial de 5 x 2, sendo o primeiro fator compreendido por cinco concentrações de nitroprussiato de sódio (NPS) (0, 50, 100, 150 e 200 µmol) e o segundo fator foi composto por dois níveis salinos da água de irrigação (0,2 e 3,5 dS m-1, respectivamente, sem e com estresse salino), com quatro repetições. As concentrações de NPS foram aplicadas semanalmente (via foliar), totalizando três ap... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In view of the current water demand for maintaining intense and successive crops, it is necessary to search for alternatives for the correct management of water in order to reduce its waste. One of these alternatives focuses on the use of lower quality water, such as brackish water. However, the use of brackish water can cause several changes in the metabolism of plants, requiring strategies that allow the use of these waters. In the search for these alternatives, biological or synthetic substances are sought that generate physiological and biochemical responses that promote the adaptation of plants to adverse environmental conditions, such as nitric oxide (NO). Based on this assumption, the aim of this study was to evaluate the attenuating effect of nitric oxide on crisp lettuce plants, cv. Vera, grown under salt stress. The experiment was carried out in a greenhouse in the months of April and May 2019, at the São Manuel da FCA Experimental Farm, located in the municipality of São Manuel / SP. The experimental design adopted was that of randomized blocks, in a 5 x 2 factorial scheme, the first factor being comprised of five concentrations of sodium nitroprusside (SNP) (0, 50, 100, 150 and 200 µmol) and the second factor was composed of two saline levels of irrigation water (0.2 and 3.5 dS m-1, respectively, without and with salt stress), with four repetitions. SNP concentrations were applied weekly (via leaf), totaling three applications during the cycle. The variables analy... (Complete abstract click electronic access below) / Mestre
97

Impact of Oyster Mushroom Mycelium on the Growth of Kale and Forage Radish

Lilly, Levi 09 July 2018 (has links)
Saprophytic fungi can be paired with companion crops in interplant systems to increase production efficiency. However, fungal species/strain, substrate, and inoculation rate can affect the growth of companion crops. This project investigated the viability of open-field mushroom production by interplanting three strains of Pleurotus ostreatus (Elm A, Elm B, and 8801) with kale (B. oleracea var. acephala) and forage radish (Raphanus raphanistrub sub. sativus), and measured the effect of interplanting on plant yield over two field seasons. In the field, Elm A showed an increase in plant yield at a low inoculation rate and decrease in plant yield at a high inoculation rate, compared to the untreated. Conversely, 8801 showed a reduction in plant yield at high and low inoculation rates in the field. Elm B at a high rate showed a reduction in plant yield both in the field and greenhouse. Kale was grown in hydroponics with fungal secretions added at a range of concentrations (10, 100, 1,000 and 10,000 ppm). Elm A showed an overall increase in plant yield in hydroponics, and Elm B showed an overall decrease in plant yield, compared to the untreated. Mushroom production was low in field plots and was not a commercially viable option. Pleurotus ostreatus interplanting methods with companion crops need improvement to make this a commercially viable practice.
98

Increasing food system sustainability using solar powered atmospheric water

Gustrin, Hanna January 2021 (has links)
This study investigates the possibilities of applying water generated from the atmosphere for agricultural processes, particularly hydroponic systems. A solar powered, off-grid greenhouse system is proposed as a theoretical solution to food production, in areas affected by water scarcity. Two experiments are conducted with the purpose of testing atmospheric water quality and how it performs in a hydroponic setting. The plausibility of powering said greenhouse system using solar energy is investigated, considering several available solar technologies. Ultimately, the footprint area required to install enough capacity to power the system is discussed, and the potential site of such a system is modelled and visualized. The experiments concluded that atmospheric water is likely suitable for hydroponic use. The study also found that the footprint area required for the greenhouse system probably can be considered reasonable for certain applications, but more research and advances within solar power technology would be beneficial / <p>2021-06-08</p>
99

Řídící jednotka pro aeroponický pěstební systém / Control unit for aeroponic growing system

Vrabec, Miroslav January 2013 (has links)
This thesis deals with the history of a method of plants cultivation without original substrate. The method is hydroponics and its subsequent development is called aeroponics. This work outlines the design of the whole aeroponic system including a control unit. The control unit has been designed to control the injection of nutrient solution, which is essential to the life of plants.Further, the control unit performs the control of lighting period, temperature, air flow and also regulation of nutrient solution pH. The control unit also keeps records of all data necessary for the monitoring process and for the evaluation of time differencies in the system.
100

Řídící jednotka pro aeroponický pěstební systém / Control unit for aeroponic growing system

Vrabec, Miroslav January 2013 (has links)
This thesis deals with the history of a method of plants cultivation without original substrate. The method is hydroponics and its subsequent development is called aeroponics. This work outlines the design of the whole aeroponic system including a control unit. The control unit has been designed to control the injection of nutrient solution, which is essential to the life of plants.Further, the control unit performs the control of lighting period, temperature, air flow and also regulation of nutrient solution pH. The control unit also keeps records of all data necessary for the monitoring process and for the evaluation of time differencies in the system.

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