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| Registros recuperados: 219 | |
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| Bazzi,Claudio L; Souza,Eduardo G; Khosla,Raj; Uribe-Opazo,Miguel A; Schenatto,Kelyn. |
| During the last few years, yield maps have become economically feasible for farmers due to technological advances in precision agriculture. However, evidence of yield profitability is still uncertain, and variability in yield has seldom been correlated to variability in profits. Differently from yield maps, profit maps can supply additional information about the economic return for each particular area of a field. The objective of the present work was to study how management decisions can be facilitated by transforming yield-map datasets into profit maps and the importance of the selection of interpolator type. Yield and profit maps were generated for each data set (three soybean fields and one corn field) using the inverse of the distance (ID), the... |
| Tipo: Journal article |
Palavras-chave: Precision agriculture; Profit map; Profitability map. |
| Ano: 2015 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-16202015000300007 |
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| Tavares,Tiago Rodrigues; Fiorio,Peterson Ricardo; Seixas,Hugo Tameirão; Garcia,Amparo Cisneiros; Barros,Pedro Paulo da Silva. |
| ABSTRACT: Vis-NIR-SWIR reflectance spectra of leaf samples, collected in the laboratory, allow the calibration of predictive models to quantify their physicochemical attributes in a practical manner and without producing chemical residues. This technique should enable the development of management strategies for intensification of pasture use. However, spectral analysis performed in the laboratory may be affected by the deterioration of plant material during transport from the field to the lab, so storage methods are necessary. This research aimed to evaluate the effects of different storage methods on the spectral response of Mombasa grass leaves. Three methods were evaluated: (i) artificially refrigerated environment, (ii) humid environment, and (iii)... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Diffuse reflectance spectroscopy; Hyperspectral sensors; Forage; Precision agriculture. |
| Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782020000300401 |
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| San Juan Martínez, Erwin. |
| El diagnóstico oportuno del estado nutrimental de los cultivos en la agricultura de precisión es de suma importancia y vitalidad; por lo que cada vez se hacen más necesarias técnicas que permitan conocer el estado nutrimental del cultivo de forma rápida, precisa y confiable. Es por ello que el presente trabajo tuvo como objetivo determinar la concentración de nitrógeno foliar en chile de agua mediante reflectancia, dicha característica se obtuvo por medio de equipos como: radiómetro (CROPSCAN), escáner de escritorio y cámara fotográfica digital, de igual forma se determinó un índice de verdor utilizando el medidor portátil SPAD Minolta 502 y, la concentración de nitrógeno foliar por el método Kjeldahl. A partir de esas mediciones y con el programa Curve... |
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Palavras-chave: Agricultura de precisión; Firmas espectrales; Nutriente; Precision agriculture; Spectral signatures; Nitrogen content; Edafología; Maestría. |
| Ano: 2014 |
URL: http://hdl.handle.net/10521/2285 |
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| Calou,Vinícius B. C.; Teixeira,Adunias dos S.; Moreira,Luis C. J.; Rocha Neto,Odílio C. da; Silva,José A. da. |
| ABSTRACT Unmanned aerial vehicles (UAVs) are a promising tool for technology development and transfer and for the economic success of the agricultural sector. The objective of this study is to assess the validity of biomass estimation in a commercial maize plantation using aerial images obtained by a UAV. The proposed methodology involved analyzing images acquired in scheduled flights, processing orthophoto (georeferenced image) data, evaluating digital terrain elevation models, and assessing the quality of dense point clouds. Data were collected using two cameras, one with a 16-megapixel flat lens and the other with a 12-megapixel fish-eye lens coupled to a UAV, at two flight altitudes (30 and 60 meters) over hybrid maize (AG1051) crop irrigated by center... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Precision agriculture; Structure from Motion; Unmanned aerial vehicles; Zea mays L. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000600744 |
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| Gadotti,Gizele I.; Corrêa,Marciabela F.; Navroski,Renan; Nadal,Ariele P.; Schuch,Luis O. B.. |
| ABSTRACT The aim of this research was to study the linear correlations and spatial distribution between soil attributes and productivity and physiological quality of wheat seeds. Soil samples were collected at georeferenced points in an area of 41 ha with a rectangular grid of 100 × 100 m to determine soil fertility. Grain productivity, number of ears m-2, protein content, and physiological seed quality were assessed. The results were submitted to Pearson's correlation analysis, descriptive statistics, and geostatistics. Phosphorus content presented a high spatial variability, with a coefficient of variation of 97.79%. Protein content, number of ears, and SMP index presented low values of coefficient of variation, indicating their low spatial variability.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Precision agriculture; Fertility; Seed quality; Triticum aestivum L.; Spatial variability. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162018000400624 |
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| Oliveira,Job T. de; Oliveira,Rubens A. de; Cunha,Fernando F. da; Santos,Eduardo S. dos. |
| ABSTRACT Studies that seek to identify a smaller number of soil attributes that represent others can generate less expenditure of time and financial resources for monitoring cultivated areas. Thus, this study aimed to analyze the spatial distribution and spatial autocorrelation of physical attributes of an Oxisol (Latossolo Vermelho Amarelo, Brazilian Soil Classification System). The evaluated attributes consisted of soil density (SD), total porosity (TP), free porosity (FP), field capacity (FC), permanent wilt point (PW), and total water availability (TW). Semivariogram adjustments and semivariance estimates were performed to characterize the structure and magnitude of the spatial dependence of soil attributes. The attributes were distributed on thematic... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Precision agriculture; Spatial dependence; Geostatistics; Moran index. |
| Ano: 2021 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162021000200255 |
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| Santos,Adão F. dos; Correa,Lígia N.; Gírio,Lucas A. S.; Paixão,Carla S. S.; Silva,Rouverson P. da. |
| ABSTRACT The use of automatic routing significantly increases the yield and quality of agricultural operations and reduces the overlap rates between the mechanized set passes during the operation. The objective of this study was to analyse the quality of peanut sowing using automatic routing in two paths, curved and rectilinear, based on the error of parallelism and execution error, through statistical process control. The maps used came from an area of peanut seed production, in the city of Luzitânia, São Paulo, Brazil. The sowing was carried out by the execution of a project elaborated in CAD software that, for its elaboration, was taken into consideration the working width of the seeder-fertilizer, as well as the spacing of the crop. The CenterPoint RTX... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Precision agriculture; Peanut; GNSS; Parallelism; RTX. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162018000400568 |
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| Ribeiro,Felipe O.; Fernandes,Antonio R.; Matos,Gilson S. B. de; Lindolfo,Marcelo M.; Guedes,Rafael S.; Rodrigues,Graziele R.. |
| ABSTRACT This study aimed to define management zones (MZs) for fertirrigated açaí cultivation, based on spatial variability of the foliar nutrients and productivity data. The work was carried out in an area of 5.75 ha of a 7-year crop, with 80 georeferenced sample points. Fresh fruit productivity and nutrient (N, P, K, Ca, Mg, S, B, Cu, Fe, Mn, and Zn) contents were determined. The average contents of macronutrients were considered adequate for adult açaí plants, and their spatial dependence associated with fruit productivity allowed the representation of their distributions through maps of variability. Through multivariate analysis, three main components were highlighted. These components explained 51.5 % of the total variability of the data, where PC1... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Amazon; Management zones; Multivariate analysis; Nutrient contents; Precision agriculture. |
| Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000600800 |
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| Stocker,Vinícius; Souza,Eduardo G. de; Johann,Jerry A.; Beneduzzi,Humberto M.; Silva,Franciléia de O. e. |
| ABSTRACT The application of nitrogen (N) fertilizer is complex and expensive, so its correct management has financial and environmental benefits. The use of optical proximity sensors is a promising technique. However, the movement of the agricultural machinery or of the person carrying the sensor will result in height differences and/or different tilt and twist angles with respect to the canopy. We considered whether these variations would affect the reflectance measurement. In this study, we took normalized difference vegetation index (NDVI) readings of a wheat canopy, to which 90 kg ha-1 of urea had been applied in stage 5, and observed the NDVI in stages 6, 8 and 10.5. We also tested soybeans, to which 90 kg ha-1 of urea had been applied in stage R1,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Nitrogen fertilization; Precision agriculture; GreenSeeker; NDVI. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000800096 |
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| Roccia,Clerivaldo; Teruel,Bárbara; Alves,Elaine C. de S.; Arnold,Francisco; Bravo-Roger,Leonardo; Moretti,Angelo; Gonçalves,Marcos S.. |
| The aim of this study was to perform an experimental study to evaluate the proper operation distance between the nodes of a wireless sensor network available on the market for different agricultural crops (maize, physic nut, eucalyptus). The experimental data of the network performance offers to farmers and researchers information that might be useful to the sizing and project of the wireless sensor networks in similar situations to those studied. The evaluation showed that the separation of the nodes depends on the type of culture and it is a critical factor to ensure the feasibility of using WSN. In the configuration used, sending packets every 2 seconds, the battery life was about four days. Therefore, the autonomy may be increased with a longer... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Maize (Zea mays L); Physic nut (Jatropha curcas); Eucalyptus (Eucalyptus grandis); Precision agriculture; Zigbee technology. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162012000600018 |
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| Spagnolo,Roger T.; Rosa,David P. da; Pinho,Marivan da S.; Schiavon,Cheiner S.; Schmechel,Diego K.. |
| ABSTRACT The use of microgranular fertilizers is currently increasing, with low application rates as an obstacle in the mechanization. This study aimed to verify the performance of helical metering mechanisms using microgranular fertilizer. Four different fertilizer-metering mechanisms were tested at two pre-established dose rates (35 and 50 kg ha−1) and seven longitudinal angles (−15°, −10°, −5°, 0°, +5°, +10°, and +15°). The experiment was carried out according to Brazilian standards. The results showed that the longitudinal inclination affects the actual fertilizer dose in all tested metering systems. Metering mechanisms with a helicoid with longitudinal and lateral overflow presented a similar dose, according to the variation of the longitudinal... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Agricultural equipment; Longitudinal inclination; Precision agriculture. |
| Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000400481 |
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| Registros recuperados: 219 | |
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