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Registros recuperados: 7.979 | |
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Silva,Edinéia F. da; Jadoski,Sidnei O.; Martinkoski,Lais. |
ABSTRACT Potato (Solanum tuberosum L.) cultivation has a high demand for management and treatments during the vegetative cycle in the field. Among these requirements, water management is a limiting factor of tuber productivity and quality. This study aimed to determine the most appropriate soil water depletion depth for irrigation management in potato crops of Ágata cultivar, under the edaphoclimatic conditions of Guarapuava-PR, considering its influence on crop vegetative development. The study was conducted using four water depletion depths in the soil (12, 24, 36, and 48 mm). The different irrigation treatments promoted differences in shoot dry mass, leaf area index (LAI), number of tubers per plant, and productivity. The highest yield was observed for... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil water; Potato cultivars; Evapotranspiration. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000400434 |
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Viais Neto,Daniel dos S.; Cremasco,Camila P.; Bordin,Deyver; Putti,Fernando F.; Silva Junior,Josué F.; Gabriel Filho,Luís R. A.. |
ABSTRACT Tomato, the most popular greenery, is characterized by being a demanding crop in water and when in prolonged and severe drought, has limitations in its growth and reduction in productivity. In addition, this vegetable is affected by excess salinity in the water, which causes leaf wilting, apex and leaf edges burn until their death. Such effects generally are studied using statistical analysis, but there are mathematical theories that allow finer adjustments, highlighting among them, the fuzzy logic. The objective of this study was to evaluate the effects on the growth and yield of hybrid tomato from different water tensions in the soil and different salinity doses in the irrigation at 120 days after sowing using fuzzy modeling. It was used data... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fuzzy logic; Hydro potential; Drought; Salt stress. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000300305 |
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Arcoverde,Sálvio N. S.; Cortez,Jorge W.; Olszevski,Nelci; Salviano,Alessandra M.; Giongo,Vanderlise. |
ABSTRACT The inadequate agricultural management in the semiarid region of northeastern Brazil, associated with the fragility of most soils, has caused degradation of the quality of this resource. This study aimed to evaluate the quality of Quartzipsamments under different uses through the multivariate analysis of chemical and physical attributes. Five areas were selected: four of them with agricultural use (onion, banana, cassava, and corn) and the other with Caatinga. Soil samples were collected at depths of 0.00–0.10, 0.10–0.20, and 0.20–0.40 m for chemical and physical analyses. The data were submitted to descriptive analysis and then to the multivariate analysis using the principal component analysis (PCA) technique and Ward’s clustering method. PCA... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Principal component; Quality indicator; Soil quality; Sandy soils. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000400457 |
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Silva,Jaqueline A. da; Rezende,Maiara K. A.; Flumignan,Danilton L.. |
ABSTRACT Plant yield is strongly influenced by the amount of water used by it. In this sense, yield response factor (Ky) allows evaluating the decrease in yield as a function of the evapotranspiration that occurs, which may be an important tool for harvest forecasting. Therefore, this study aimed to determine Ky for winter corn crop grown in the region of Dourados, MS, Brazil. The yield function analysis based on the water factor, which requires actual (Ya) and maximum (Ym) yield data, as well as actual (ETa) and maximum (ETm) evapotranspiration, was used to adjust Ky. Ym was assumed to be 8,820 kg ha−1, while Ya was obtained for each season from the database SIDRA from IBGE. ETm and ETa were estimated by sequential daily water balance, considering four... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Irrigation; Water deficit; Evapotranspiration; Zea mays. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000500573 |
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Christoforo,André L.; Almeida,Andrea de S.; Lanini,Tamiris L. S.; Nogueira,Rodrigo de S.; Lahr,Francisco A. R.. |
ABSTRACT For safety reasons, wood strength values, essential for structural dimensioning, are calculated based on the characteristic value, which corresponds to the 5% percentile of a given probability distribution model. For small samples, the Brazilian normative document ABNT NBR 7190 establishes an estimator of the characteristic wood strength, which can provide a significantly different result from the characteristic value coming from a suitable model of probability distribution. The main objective of this study was to evaluate the best probability distribution model (normal, lognormal, Weibull, and exponential) and the subsequent calculation of the characteristic value indicated by ABNT NBR 7190 (1997), allowing to evaluate its accuracy, being also... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Wood; Compression; Traction; Shear; Probability distribution; Characteristic value. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000100127 |
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Ferraz,Marcos N.; Corrêdo,Lucas de P.; Wei,Marcelo C. Fu; Molin,José P.. |
ABSTRACT Spatial variability evaluation of qualitative attributes can be used as an excellent strategy to design forms of intervention that result in better crop profitability for some agricultural crops, for example, sugarcane. Based on the assumption that qualitative attributes of sugarcane present spatial variability and their distributions along the stems are uniform in different varieties, this study aimed to evaluate the distributions of the qualitative parameters of different sugarcane varieties and the spatial variability of these attributes in a commercial field. Samples of nine varieties were collected for laboratory quality analysis, and the Brix parameter was analyzed by a digital refractometer. The analysis of variance, the Tukey test, and... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Saccharose; Technological quality; Geostatistic. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000800109 |
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Assunção,Heli H. T. de; Silva,Sérgio M.; Alves,Guilherme S.; Zandonadi,Cesar H. S.; Cunha,João P. A. R. da. |
ABSTRACT Electrostatic spray can bring benefits to the pesticide application such as the reduction of application rate and the increase of deposits on targets. Therefore, this study aimed to evaluate the effect of electrostatic spraying using lower application rates and different adjuvants on soybean spray deposition and chemical control of powdery mildew (Microsphaera diffusa Cooke & Peck). The field experiment was conducted in duplicate. A randomized complete block design with four replications in a 2 × 2 × 2 + 1 factorial scheme was used. The factors were two application rates, with and without droplet electrification, two spray solution compositions, and one additional treatment. Deposition on upper and lower leaves, spray loss to the soil, and... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Application rate; Droplet electrification; Application technology; Microsphaera diffusa. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000600721 |
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Lourençoni,Dian; Yanagi Junior,Tadayuki; Abreu,Paulo G. de; Campos,Alessandro T.; Yanagi,Silvia de N. M.. |
ABSTRACT Broiler chickens are classified as homoeothermic animals and require a production environment within well-defined thermal comfort intervals. Therefore, the development of algorithms (mathematical models) to control the environment that can be embedded in microcontrollers becomes necessary. Hence, this work aimed to develop a fuzzy model for predicting the productive performance of broiler chickens as a function of the thermal environment during the various breeding phases. The Mamdani inference and defuzzification methods were used, by means of the gravity center, to develop the fuzzy model. Two hundred and forty-three rules with weighting factors of 1.0 each were elaborated. Three commercial warehouses (conventional system, wind tunnel with... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Poultry farming; Productive performance; Artificial intelligence; Fuzzy logic. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000100001 |
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Lopes,Allan R.; Marcolin,Jonatas; Johann,Jerry A.; Boas,Márcio A. Vilas; Schuelter,Adilson R.. |
ABSTRACT The aim of this study is to identify homogeneous rainfall zones in the winter and summer 1st and 2nd crops, in the state of Paraná, Brazil. The zones were defined by clustering using the expectation-maximization (EM) algorithm to transform seasonal rainfall series. Monthly average rainfall data collected from 157 weather stations for 20 years (1996 to 2015) were employed. The results show that the number of homogeneous zones varied among growing seasons. The summer crop presented two clusters, with rainfall averages of 1489 and 1925 mm; the second crop presented four clusters, with averages of 1849, 1004, 1454, and 1182 mm; and the winter crop had three clusters, with averages of 969, 1498, and 1171 mm. Clustering was a useful instrument to... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Data mining; Clusters; Expectation-maximization; Weka; Soybean; Maize; Wheat. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000600707 |
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Luciano,Karina M da F.; Mata,Mario E. R. M. Cavalcanti; Fortes,Mauri; Duarte,Maria E. M.. |
ABSTRACT Cryopreservation is a technique used to preserve genetic material at ultra-low temperatures in cryogenic germplasm banks. In order to enable the cryopreservation of a seed, it is necessary to study its appropriate freezing temperature and its water content, because seeds reach maximum physiological quality with high water contents, and they tolerate drying when they are orthodox seeds, but they may not tolerate cryopreservation. Therefore, the objective of this study was to analyze the influence of initial water content (50 to 10% wet basis) on the kinetic behavior of the lima bean seed at the temperature of −150 °C, in addition to determining changes in its physiological quality (germination and vigor) when cryopreserved (−150 °C) for 30 days... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Phaseolus lunatus; Cryogenic; Modeling; Germplasm bank. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000300331 |
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Zhao,Yun; Guindo,Mahamed L.; Xu,Xing; Shi,Xiang; Sun,Miao; He,Yong. |
ABSTRACT We propose a segmentation algorithm for raisin extraction. The proposed approach consists of the following aspects. Deep learning is used to predict the number of raisins in each connected region, and the shape features such as the roundness, area, X-axis value for the centroid, Y-axis value for the centroid, axis length and perimeter of each region will be used to establish the prediction model. Morphological analysis, based on edge parameters including the polar axis, polar angle and angular velocity, is applied to search for the suitable break points that are useful for identifying the dividing lines between two adjacent raisins. To make our segmentation more accurate, some machine-learning algorithms such as the random forest (RF), support... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Raisin extraction; Segmentation algorithm; Deep learning; Image analysis; Food quality grading. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000500639 |
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Melo,Adriano A.; Hunsche,Mauricio; Guedes,Jerson V. C.; Hahn,Lucas; Feltrin,Natalie M.. |
ABSTRACT The association of adjuvants with phytosanitary products has been tested for several years but is commonly recommended without considering technical and scientific criteria. This study aimed to evaluate the influence of the association of insecticides with different adjuvants on surface tension, contact angle, coverage, hydrogen ionic potential (pH), and the formation of deposits exposed to rain. The insecticides thiamethoxam, imidacloprid, and lambda-cyhalothrin were tested at doses of 75 g ha−1, 150 g ha−1, and 150 g ha−1, respectively, with a spray volume of 200 L ha−1. Break-Thru 240®, Break-Thru 233®, Break-Thru Union®, Oleo FC Agraröl®, and Naturo'il® were added to each of these spray solutions. The results showed that the addition of... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Surface tension contact angle potential of hydrogen (pH) coverage; And deposit. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000300315 |
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Landim,Thiago N.; Cunha,João P. A. R. da; Alves,Guilherme S.; Marques,Matheus G.; Silva,Sérgio M.. |
ABSTRACT Adjuvants are tools to maximize pesticide spray quality. This study aimed to evaluate the interaction effects between adjuvants and the fungicide azoxystrobin + benzovindiflupyr on the physicochemical characteristics, droplet evaporation time, and spray droplet size. The experiment was carried out using a 2×6 factorial scheme, in which the first factor was the absence or presence of the fungicide mixture (water or water + fungicide) and the second factor was the presence of different adjuvants (water and five adjuvants). The parameters evaluated were surface tension, pH, viscosity, electrical conductivity, droplet evaporation time, volume median diameter, percentage of droplets smaller than 100 μm, and relative amplitude of the droplet spectrum.... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Spray solution additives; Droplet spectrum; Surfactants; Application technology. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000500600 |
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Souza,Diene G.; Resende,Osvaldo; Moura,Lígia C. de; Ferreira Junior,Weder N.; Andrade,José W. de S.. |
ABSTRACT Biofortified sweet potato (Ipomoea batatas) is one of the foods with the highest contributions of carotenoids in the diet, especially provitamin A carotenoids. Thus, this study aimed to analyze the drying kinetics of the biofortified sweet potato pulp using the Akaike (AIC) and Schwarz's Bayesian (BIC) information criteria for model selection, as well as determine the effective diffusion coefficient and activation energy under different drying conditions. The biofortified sweet potatoes were sliced into chips and submitted to drying in an air circulation oven at 1.0 m s−1 at temperatures of 45, 55, 65, and 75 °C until constant mass. The mathematical models Wang and Singh, Verma, Thompson, Page, Newton, Midilli et al., logarithmic, Henderson and... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Liquid diffusion; Activation energy; Wang and Singh. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000200176 |
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Registros recuperados: 7.979 | |
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