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Registros recuperados: 5.225 | |
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Calegario,Arthur T.; Pruski,Fernando F.; Ribeiro,Rayssa B.; Ramos,Maria C. A.; Rego,Fernando S.. |
ABSTRACT Regionalization is an important technique for estimating the flow of hydrographic sections with a lack of data. First, it is necessary to identify hydrologically homogeneous regions (HHRs), which are commonly validated via statistical analyses. Because this step is understood to be subjective, studies that contribute to a greater reliability in identifying regions are needed. In this context, the objective was to evaluate the inclusion of a physical analysis of the average regionalized flow rates as an aid to identify HHRs. The groupings were defined on the basis of geographical convenience methods and cluster analysis. For the assessment of regionalized flows, six statistical indices were used with a physical analysis that was performed via a... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Regionalization; Long-term average streamflow; Planning and management of water resources; Cluster analysis; Geographical convenience. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000300334 |
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Rodrigues,Tatiana P. N. da S.; Pandorfi,Héliton; Stosic,Borko; Lucena,Aline C. de; Rodrigues,Diogo F. B.. |
ABSTRACT The objective of this study was to develop a software based on image processing and computer vision techniques for monitoring the feeding/collective behavior of broilers (Cobb) and validate it based on the results obtained from the visual analysis of an expert. The visual analysis was performed based on the observation and quantification of behaviors in the interval of 10 min at each hour of the day, in the period of 24 hours, totaling 1728 frames/day, for males and females. The software was developed using the Hoshen-Kopelman algorithm, for labeling clusters, which would basically be the grouping of similar pixels. This software is written in the 1999 standard of the C language. After this stage of programming, the Hoshen-Kopelman algorithm... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Broiler farming; Image processing; Lighting system; Computer vision. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000600657 |
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Santos,Paulo S. B. dos; Ramos,Ricardo A. V.. |
ABSTRACT The sugar-energy sector stands out in the production of electrical energy in the Brazilian energy matrix. The updating of Law 9,427 allowed increasing the limit of power injected in the transmission or distribution systems of existing projects from 30 to 50 MW, encouraging studies of expansion and/or implementation of new cogeneration projects. This study analyzed technologies to enhance energy cogeneration in a plant that sells about 27 MW of surplus power. For this, were studied the use of straw, electrification of drives by steam turbines, and high-drainage rollers (lotus mill roller), which allows reducing bagasse moisture, increasing its lower calorific value (LCV) and, consequently, electrical energy generation. Mass and energy balances in... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Bioelectricity; Biomass; Combustion; Calorific value; Numerical simulation. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000200249 |
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Rodriguez,Yeison F. B.; Guzman,Nelson G.; Hernandez,Joel G.. |
ABSTRACT The objective of this work was to study the influence of two postharvest processing methods on the biochemical composition and sensory analysis of a Colombian specialty coffee. For this purpose, coffee beans (Coffea arabica) of the Castillo variety were collected and processed using the wet and semi-dry methods, and the drying process was conducted in a sun drier prototype with a plastic parabolic cover, with a maximum drying air temperature of 50 °C; green coffee beans were managed according to the official Specialty Coffee Association cupping protocol and roasted to a medium and dark degree. Physicochemical determinations (pH, color, titratable acidity, caffeine content, and chlorogenic acid quantification) in green coffee and roasted coffee... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Caffeine; Coffee roasting; Coffee processing; Cup quality; Chlorogenic acids. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000200177 |
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Sarmiento,Christiany M.; Coltri,Priscila P.; Alves,Marcelo de C.; Carvalho,Luiz G. de. |
ABSTRACT This study used spectral data integrated with the agrometeorological model by Doorenbos and Kassam to estimate soybean grain productivity in the state of Mato Grosso, Brazil. In the developed model, spectral data were used instead of meteorological data and biophysical parameters of the crop. For this purpose, the products of real and potential evapotranspiration (MOD16), normalized difference vegetation index – NDVI (MOD13Q1), and leaf area index (MOD15A2H) from the MODIS satellite were used, in addition to sunstroke data obtained by using the visible channel from the satellite GOES IMAGER. The results obtained showed that, with the proposed methodology, it was possible to follow the development of soybean cultivation throughout the cycle and to... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Geographic Information System; Mathematical Modeling; Remote Sensing; Agrometeorology; Crop Monitoring. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000300405 |
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Christoforo,André L.; Almeida,Diego H. de; Varanda,Luciano D.; Panzera,Tulio H.; Lahr,Francisco A. R.. |
ABSTRACT Wood has been used for several purposes such as in civil and rural construction. Knowing wood mechanical behavior under short-term loading is essential for safer structural designs. However, wood toughness is a mechanical property little investigated for this purpose. Thus, this study aimed to evaluate, using exponential and polynomial regression models (linear, quadratic, and cubic), the possibility of estimating toughness as a function of apparent density, compression parallel to grain strength, and modulus of rupture in static bending. Thirty-six Brazilian tropical wood species from south of Roraima, Mato Grosso do Sul, and north and northeast of Mato Grosso were tested. Our results showed the significance and representativeness of all... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Apparent density; Tropical wood species; Modulus of elasticity; Compression parallel to grain strength; Toughness. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000200232 |
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Silva,Mairton G. da; Soares,Tales M.; Gheyi,Hans R.; Oliveira,Mateus G. B. de; Santos,Caroline C. dos. |
ABSTRACT A large number of studies on salinity in hydroponic systems have been carried out, but few of them have evaluated the interaction between salinity and nutrient solution temperatures. Two experiments were carried out in a randomized block design from January to February (Experiment I) and June to July 2018 (Experiment II). Experiment I consisted of treatments with five combinations, as follows: unheated (control) and heated nutrient solution (NS) at a temperature of 32°C using fresh water with an electrical conductivity (ECw) of 0.3 dS m−1, and unheated and heated NS at temperatures of 30 and 32°C using brackish water with an ECw of 6.5 dS m−1 in the main plots, with two coriander cultivars (Tabocas and Verdão) in the subplots, which were grown in... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Coriandrum sativum L. abiotic stress shoot fresh matter hydroponics; Salinity. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000600674 |
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Dias,Camila de A.; Andrade,Ednilton T. de; Lemos,Isabella A.; Borém,Flávio M.; Barros,Ezequiel A.. |
ABSTRACT The aim of this study was to evaluate and model the hygroscopic equilibrium and isosteric heat curves of pericarp and endosperm tissues of arabica (Coffea arabica) coffee fruit, in different temperature and relative humidity conditions. Sorption isotherms were drawn under temperatures from 20°C to 70°C and relative humidity ranging between 10% and 90% until the product reached the equilibrium water content with the environment. The experiment was set up in a 4 × 4 factorial scheme (four relative humidity of the drying air and three tissues of the coffee cherry pericarp + endosperm [1: exocarp + part of the mesocarp, 2: mesocarp, 3: endocarp, 4: endosperm]), in a completely randomized design, with three repetitions. The results were examined by... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Adsorption; Coffea arabica; Desorption; Hygroscopic equilibrium; Mathematical modeling. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000100078 |
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Paixão,Carla S. S.; Voltarelli,Murilo A.; Silva,Rouverson P. da; Borba,Mateus A. de P.; Torres,Luma S.. |
ABSTRACT The mechanized sugarcane harvesting process is considered one of the major economic bottlenecks, with low operational efficiency and, mainly, high losses of stalks left in the field. In order to minimize these problems and assist in the improvement of processes, this study aimed to evaluate the losses in the mechanized sugarcane harvesting using statistical process control. The experimental design was completely randomized, based on the methodology of statistical process control with samples collected on five work fronts during the daytime and nighttime operation. The experiment was carried out in an agricultural area of a sugarcane mill in the municipality of Ribeirão Preto, SP, Brazil, on five sugarcane harvest fronts. Losses were measured using... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Harvester; Visible losses; Saccharum spp. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000400473 |
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Abreu,Lucas H. P.; Yanagi Junior,Tadayuki; Bahuti,Marcelo; Hernández-Julio,Yamid F.; Ferraz,Patrícia F. P.. |
ABSTRACT Due to a number of factors involving the thermal environment of a broiler cutting installation and its interaction with the physiological and productive responses of birds, artificial intelligence has been shown to be an interesting methodology to assist in the decision-making process. For this reason, the main aim of this work was to develop an artificial neural network (ANN) to predict feed conversion (FC), water consumption (Cwater), and cloacal temperature (tclo) of broilers submitted to different air dry-bulb temperatures (24, 27, 30, and 33°C) and durations (1, 2, 3, and 4 days) of thermal stress in the second week of the production cycle. Relative humidity and wind speed were fixed at 60% and 0.2 ms−1, respectively. The experimental data... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Poultry; Thermal stress; Artificial intelligence. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000100001 |
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Zhou,Zheng; Liang,Chunying. |
ABSTRACT The soaking and germination process of rice seeds is the starting point in rice cultivation in cold regions and has a significant effect on grain yield. Efficient techniques for controlling the water temperature in the seed tank are required to enhance germination quality. This paper introduces a fuzzy theory for designing a fuzzy logic-based sliding mode controller (SMC) system for a rice seed soaking and germination device. The proposed system was theoretically and experimentally investigated to determine the efficiency of the soaking temperature-control system. A modified fuzzy SMC based on exponent approaching law is also presented for optimizing the proposed controller. A proportional integral derivative (PID) controller was designed to... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fuzzy sliding-mode control; Temperature controller; Soaking; Germination. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000200215 |
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Cunha,João P. A. R. da; Palma,Roxanna P.; Oliveira,Arthur C. de; Marques,Matheus G.; Alvarenga,Cleyton B. de. |
ABSTRACT The hardness and pH of the spray water can interfere with the weed control effectiveness with herbicides, but it is not clear the magnitude of this interference, mainly associating different levels of pH and hardness to different glyphosate formulations. This study aimed to evaluate the influence of hardness and pH, in association, of the water used in the application of two glyphosate formulations on the weed control effectiveness. The experiment was conducted in duplicate, in areas with a predominance of Digitaria horizontalis, under a randomized block design with a 4×4×2+1 factorial scheme, composed of four water hardness levels (70, 110, 230, and 430 ppm CaCO3), four pH levels (3.5, 4.5, 5.5, and 6.5), two glyphosate formulations (ammonium... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Herbicide; Water quality; Spraying; Application technology. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000400555 |
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Cortez,Jorge W.; Anghinoni,Matheus; Arcoverde,Sálvio N. S.. |
ABSTRACT Seed metering system and tractor-seeder forward speed are factors that affect sowing. Therefore, this study aimed to evaluate sowing and agronomic components of corn as a function of seed metering mechanism and tractor-seeder forward speed, in addition to evaluating the yield data obtained from a harvester with a yield monitor. The soil of the area is classified as Distroferric Red Latosol. The experiment was set up in the second crop season of 2018 and treatments consisted of two seed metering mechanisms (M) (pneumatic and mechanical), and tractor-seeder forward speeds (S) (3, 5, 7, and 9 km h−1). The pneumatic system promoted the best longitudinal distribution, with values above 90%, and the increased sowing forward speed reduced normal spacings... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Grain yield; Pneumatic sowing; Sowing forward speed. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000100061 |
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Registros recuperados: 5.225 | |
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