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| Registros recuperados: 47 | |
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| Alves,Guilherme E.; Borém,Flávio M.; Andrade,Ednilton T.; Isquierdo,Éder P.; Siqueira,Valdiney C.; Dias,Camila de A.. |
| ABSTRACT This study aimed to evaluate drying kinetics for natural and pulped coffee, using different temperatures and drying airflows. For the conduction of the experiment, coffee fruits (Coffea arabica L. cv. Topázio) were harvested manually, selecting only ripe fruits and subsequent to the hydraulic separation. For drying the coffee, use a mechanical dryer with two temperatures (40 and 45°C) and four drying air streams (24; 60; 96 and 132 m3.min-1.m-2). Twelve models for employees to describe the drying kinetics of coffees. Among the models used to describe the drying process of natural coffee and pulped coffee, according to the results of the coefficient of determination, relative mean error, standard deviation of estimates and distribution of waste... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Coffea arabica L.; Mathematical modeling; Drying rate. |
| Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000200192 |
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| Resende,Osvaldo; Oliveira,Daniel E. C. de; Costa,Lílian M.; Ferreira Júnior,Weder N.. |
| ABSTRACT This study aimed to fit different mathematical models to the experimental data on drying of baru fruits (Dipteryx alata Vogel), determine and assess the effective diffusion coefficient, as well as obtain the activation energy and thermodynamic properties for the drying process under different air temperature conditions. Baru fruits with an initial moisture content of 0.429 ± 0.044 (dry basis, db) were dried in a forced air ventilation oven under four temperature conditions (40, 60, 80, and 100 °C) until reaching a moisture content of 0.065 ± 0.018 (decimal db). These data were fitted to mathematical models frequently used to represent the drying of vegetal products. The Logarithmic model presented the best fit to describe the phenomenon. The... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Mathematical modeling; Liquid diffusivity; Logarithmic. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162018000100103 |
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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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| Ponciano,Patrícia F.; Yanagi Junior,Tadayuki; Lima,Renato R. de; Schiassi,Leonardo; Teixeira,Vitor H.. |
| The broiler rectal temperature (t rectal) is one of the most important physiological responses to classify the animal thermal comfort. Therefore, the aim of this study was to adjust regression models in order to predict the rectal temperature (t rectal) of broiler chickens under different thermal conditions based on age (A) and a meteorological variable (air temperature - t air) or a thermal comfort index (temperature and humidity index -THI or black globe humidity index - BGHI) or a physical quantity enthalpy (H). In addition, through the inversion of these models and the expected t rectal intervals for each age, the comfort limits of t air, THI, BGHI and H for the chicks in the heating phase were determined, aiding in the validation of the equations and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Thermal environment; Poultry; Thermal comfort; Mathematical modeling; Physiological responses. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162012000100002 |
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| Abreu,Lucas H. P.; Yanagi Junior,Tadayuki; Campos,Alessandro T.; Lourençoni,Dian; Bahuti,Marcelo. |
| ABSTRACT Broiler chickens submitted to different intensities and durations of thermal stress are subject to variation in cloacal temperature and, consequently, to a decrease in performance. Given the complexity of these interactions, artificial intelligence is a useful methodology for decision-making. Thus, this study aimed to assess and predict, by means of a fuzzy model, the cloacal temperature of broiler chickens submitted to thermal stress in the second week of life, with varying durations and intensities, in climatized wind tunnels. Mamdani's inference and defuzzification methods by means of the center of gravity were used. One hundred and twenty rules were elaborated. The developed fuzzy model was used to predict the cloacal temperature of broiler... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Physiological response; Thermal environment; Mathematical modeling; Fuzzy logic. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000100018 |
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| Rosa,Stefanie Lais Kreutz; Souza,Jorge Luiz Moretti de; Tsukahara,Rodrigo Yoiti. |
| Abstract: The objective of this work was to calibrate and validate the AquaCrop model for the wheat (Triticum aestivum) crop in the Campos Gerais region, in Southern Brazil. Five cultivars were evaluated in the harvests from 2007 to 2017. The input data for AquaCrop - related to climate, crop, soil, and soil management -, collected in the field, were obtained from the database of Fundação ABC and from the literature. From 35 to 43% of total harvests were selected for calibration, and the remaining, for validation. Calibration was performed for the parameters most sensitive to crop potential yield penalty. The simulated yields were compared with those observed in the field through simple linear regression analysis, root mean square error (RMSE), Pearson’s... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Triticum aestivum; Crop yield; Mathematical modeling. |
| Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2020000101000 |
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| Silva,Alysson Jalles da; Sanches,Adhemar; Andrade,Andréa Carla Bastos; Oliveira,Gustavo Hugo Ferreira de; Mauro,Antonio Orlando Di. |
| Abstract: The objective of this work was to compare the Bayesian approach and the frequentist methods to estimate means and genetic parameters in soybean multienvironment trials. Fifty-one soybean lines and four controls were evaluated in a randomized complete block design, in six environments, with three replicates, and soybean grain yield was determined. The half-normal prior and uniform distributions were used in combination with parameters obtained from data of 18 genotypes collected in previous and related experiments. The genotypic values of the genotypes of high- and low-grain yield, clustered by the Bayesian approach, differed from the means obtained by the frequentist inference. Soybean assessed through the Bayesian approach showed genetic... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Glycine max; Mathematical modeling; Prior distribution in plant breeding. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2018001001093 |
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| Gonçalves,CA; de Almeida,MA; Faria-Júnior,MJA; Pinto,MF; Garcia-Neto,M. |
| Nutritionists need to make commercial decisions about the optimal nutrient content broiler feeds. In order to demonstrate that broiler prices may influence dietary nutrient density, this study developed quadratic feed intake and weight gain equations, according to broiler sex and feeding phase, to be applied in a nonlinear feed formulation model. Four hundred and eighty Cobb broilers were allotted to a completely randomized experimental with six treatments, each with four replicates of 10 birds each, from 1 to 56 days old. Treatments consisted of diets containing 2800, 2900, 3000, 3100, 3200, or 3300 kcal metabolizable energy (ME)/kg and constant nutrient to ME ratio. A nonlinear version of the PPFR feed formulation software (http://www.fmva.unesp.br/ppfr)... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Energy; Excel; Mathematical modeling; Nutrition; Response surface. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-635X2015000200173 |
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| Almeida,TW; Silva,AL; Saccomani,AP; Muñoz,JA; Silva,RT; Franca,NV; Faria,DE; Faria Filho,DE. |
| ABSTRACT Feed formulation using linear programming consists of determining the mixture of feedstuffs required to meet pre-established animal nutritional requirements at the lowest cost. On the other hand, with the use of non-linear programming, it is possible to define nutritional requirements at the time of formulation, aiming at maximum profit. The objective of the present study was to compare feeds formulated using linear and non-linear programming in terms of live performance and internal and external egg quality of commercial laying hens. A total of 288 Hisex® White laying hens, 1.540 ± 0.128 g body weight, were evaluated from 33 to 45 weeks of age. Hens were distributed in a completely randomized block design, including six treatments with six... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Diminishing returns; Linear programming; Mathematical modeling; Meta-analysis; Profit.. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-635X2019000300313 |
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| Pereira,Emmanuel M.; Silva,Wilton P. da; Gomes,Josivanda P.; Silva,Cleide M. D. P. da S. e; Formiga,Anderson dos S.; Costa,Franciscleudo B. da. |
| ABSTRACT The objective of this study was to describe the technological process involved in the drying kinetics of fresh-cut prickly pear shoots through numerical and analytical solutions. Shoots of two different prickly pear species were used, ‘Gigante’ and ‘Miúda’. Drying was performed at different temperatures (50, 60, 70 and 80 °C) and weighing procedures were made continuously. The experimental data were expressed as moisture ratio. The Page model showed the best fit to the drying kinetics of minimally processed ‘Gigante’ and ‘Miúda’ prickly pear shoots, with the best coefficients of determination and Chi-square. Peleg and Wang & Singh models can not be used to simulate the drying of ‘Gigante’ and ‘Miúda’ prickly pear shoots within the evaluated... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Mathematical modeling; Opuntia; Nopalea; Minimal processing. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662017001100798 |
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| Smaniotto,Thaís A. de S.; Resende,Osvaldo; Sousa,Kelly A. de; Oliveira,Daniel E. C. de; Campos,Rafael C.. |
| ABSTRACT The objectives of this study were to fit different mathematical models to experimental data of drying of sunflower grains, determine and evaluate the effective diffusion coefficient and obtain the activation energy for the process during the drying under various conditions of air. The sunflower grains were collected with an initial moisture content of 0.5267 dry basis (d.b.) and dried in an oven with forced air ventilation under five temperature conditions: 35, 50, 65, 80 and 95 °C, until reaching the moisture content of 0.0934 ± 0.0061 (d.b.). Among the analyzed models, Wang and Singh showed the best fit to describe the drying phenomenon. The effective diffusion coefficient of sunflower grains increased with the increment in air temperature and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Mathematical modeling; Heliantus annus; Liquid diffusivity. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662017000300203 |
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| Campos,Renata C.; Corrêa,Paulo C.; Fernandes,Lara S.; Baptestini,Fernanda M.; Costa,Cristian F.; Bustos-Vanegas,Jaime D.. |
| ABSTRACT This study aimed to evaluate the effect of mechanical damage on the hysteresis of beans with induced mechanical damage under different conditions of temperature and relative humidity. Beans (Phaseolus vulgaris L.) harvested manually with 35% water content (w.b.) were used. Part of this product was subjected to induced mechanical damage by Stein Breakage Tester and controlled drying (damaged and control sample), for sorption processes. The sorption isotherms of water were analyzed for different temperature conditions: 20, 30, 40 and 50 oC; and relative humidity: 0.3; 0.4; 0.5; 0.7 and 0.9 (decimal). Equilibrium moisture content data were correlated with six mathematical models, and the Modified Oswin model was the one that best fitted to the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Mechanical damage; Equilibrium moisture content; Sorption isotherms; Mathematical modeling; Phaseolus vulgaris L.. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662016001000930 |
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| Oliveira,Daniel E. C. de; Resende,Osvaldo; Costa,Lílian M.; Ferreira Júnior,Weder N.; Igor O. F.,Silva. |
| ABSTRACT With the knowledge on the hygroscopic equilibrium of the baru (Dipteryx alata Vogel) fruit, the product can be adequately handled to maintain the moisture content at the levels recommended for safe storage. Thus, this paper aimed to determine the water desorption isotherms of baru fruits at temperatures of 20, 25, 30 and 35 °C, and water activity between 0.14 and 0.80, and obtain the values of isosteric heat of desorption as a function of the equilibrium moisture content of the product. The equilibrium moisture content was obtained using the static-gravimetric method. Modified Halsey was the best model recommended to represent the hygroscopicity of baru fruits. The recommended moisture contents for safe storage of baru fruits are not more than... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Equilibrium moisture content; Mathematical modeling; Desorption isotherms. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662017000400279 |
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| Cavalcante,Maisa D.; Plácido,Geovana R.; Oliveira,Daniel E. C. de; Freitas,Bheatriz S. M. de; Cagnin,Caroline; Oliveira,Déborah de S.. |
| ABSTRACT Yellow mombin has high nutritional value but is very perishable. Foam mat drying is a method that has been widely used to preserve liquid and semi-solid powdered foods. In this context, the aim of this study was to determine desorption isotherms and isosteric heat of yellow mombin (Spondias mombin L.) foam for different conditions of temperature and water activity. Powdered yellow mombin pulp was obtained by drying in forced-air oven regulated to 60 ° C. The indirect static method was used to determine the isotherms and isosteric heat, whereas water activity (aw) was determined using the Hygropalm-HP23AW-A analyzer. A B.O.D. incubator, set at 10, 20, 30 and 40 °C, was used to control the temperature, and the water activity for each temperature was... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Water activity; Isosteric heat; Hygroscopicity; Mathematical modeling; Spondias mombin L.. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662018000600436 |
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| Registros recuperados: 47 | |
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