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| Rocha,Hermes S. da; Marques,Patricia A. A.; Camargo,Antonio P. de; Frizzone,José A.; Saretta,Ezequiel. |
| ABSTRACT Assuming that a roughness meter can be successfully employed to measure the roughness on the internal surface of irrigation pipes, this research had the purpose of defining parameters and procedures required to represent the internal surface roughness of plastic pipes used in irrigation. In 2013, the roughness parameter Ra, traditional for the representation of surface irregularities in most situations, and the parameters Rc, Rq, and Ry were estimated based on 350 samples of polyvinyl chloride (PVC) and low-density polyethylene (LDPE) pipes. Pressure losses were determined from experiments carried out in laboratory. Estimations of pressure loss varied significantly according to the roughness parameters (Ra, Rc, Rq, and Ry) and the corresponding... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Friction factor; Head loss; Roughness meter. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662017000300143 |
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| Saretta,Ezequiel; Camargo,Antonio P. de; Botrel,Tarlei A.; Pinto,Marinaldo F.; Katsurayama,Geancarlo T.; Frizone,José A.. |
| ABSTRACT Current meters are equipment widely used for estimating flow velocity in rivers and streams. Periodic calibrations of current meters are important to ensure the quality of measurements, but the required testing facilities are complex and only available in a few institutions. However, advances in electronics and automation may contribute to developing simple and reliable calibration systems. Thus, this study aimed to develop an automated system for testing current meters, which consisted of a trapezoidal channel, a step motor, a tow car and a management system, composed of a supervisory application and microprocessed modules to control the motor and the data acquisition. Evaluations of the displacement velocity showed that it matched the reference... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Hydrometry; Electronics; Automation; Calibration. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662016000200181 |
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| Katsurayama,Geancarlo T.; Saretta,Ezequiel; Camargo,Antonio P. de; Botrel,Tarlei A.; Salvador,Conan A.. |
| ABSTRACT Design of lateral lines consisting of microtubes enables to optimize water distribution uniformity. In addition, there must exist a range of pressures at the lateral line inlet in which the water distribution uniformity remains acceptable. Thus, such emitters are interesting for use in micro-irrigation systems supplied by alternative power sources, in which temporal variability in the electrical power supplied to the pumping systems normally occurs. This study presents a methodology for designing lateral lines with microtubes operated under varying pressure, using the step-by-step method in order to establish the recommended range of lateral line inlet pressures. The proposed methodology was validated over three replicates by testing maximum,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Micro-irrigation; Alternative power sources; Distribution uniformity. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662017000900594 |
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| Comiran,Flávia; Bergamaschi,Homero; Heckler,Bruna Maria Machado; Santos,Henrique Pessoa dos; Alba,Diane; Saretta,Ezequiel. |
| O uso de coberturas plásticas sobre vinhedos tem aumentado no Sul do Brasil, visando a atenuar limitações climáticas. Este estudo objetivou quantificar alterações micrometeorológicas causadas por cobertura plástica e seus efeitos no desenvolvimento e na produção de videiras 'Niágara Rosada', em cultivo orgânico. O estudo foi realizado em Bento Gonçalves-RS, num vinhedo conduzido em sistema latada e submetido a dois ambientes: em céu aberto e coberto por plástico transparente (160µm) em arcos descontínuos. Nos dois ambientes, foram monitoradas radiação fotossinteticamente ativa (RFA) e temperatura do ar. Avaliaram-se fenologia, índice de área foliar (IAF), peso e diâmetro de bagas, teor de sólidos solúveis e acidez total titulável, incidência de doenças... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Vitis labrusca; Fenologia; Plasticultura. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-29452012000100021 |
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