


Registros recuperados: 60  

 

 


Demuner,Leandro Félix; Suckeveris,Diana; Muñoz,Julian Andrés; Caetano,Vinicius Camargo; Lima,Cesar Gonçalves de; Faria Filho,Daniel Emygdio de; Faria,Douglas Emygdio de. 
Abstract: The objective of this work was to investigate adjustments of the Gompertz, Logistic, von Bertalanffy, and Richards growth models, in male and female chickens of the Cobb 500, Ross 308, and Hubbard Flex lines. Initially, 1,800 chickens were randomly housed in 36 pens, with six replicates per lineage and sex, fed ad libitum with feed according to gender, and bred until 56 days of age. Average weekly body weight for each line and sex was used to estimate model parameters using the ordinary least squares, weighted by the inverse variance of the body weight and weighted with a firstorder autocorrelated error structure. Weighted models and weighted autocorrelated error models showed different parameter values when compared with the unweighted models,... 
Tipo: Info:eurepo/semantics/article 
Palavraschave: Autocorrelated errors; Autoregressive model; Poultry science; Homogeneity of variance; Mathematical model; Weighting structures. 
Ano: 2017 
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100204X2017001201241 
 


Boutron, Olivier; Bertrand, Olivier; Fiandrino, Annie; Hoehener, Patrick; Sandoz, Alain; Cherain, Yves; Coulet, Eric; Chauvelon, Philippe. 
The spatiotemporal structure of winddriven circulation patterns and associated water exchanges can drive important biohydrodynamic interactions in shallow lagoons. The Vaccares lagoon system is a complex shallow hydrosystem located in the central part of the Rhone Delta (France). It is internationally recognized as part of a biosphere reserve within the framework of UNESCO's Man and Biosphere Programme, and as a RAMSAR site. Due to its frequent occurrence in this area, and considering the shallowness of the Vaccares lagoon system, wind is assumed to play a major role in the hydrodynamic and biological processes. In this study, a hydrodynamic model was developed to investigate the structure of winddriven circulations in the Vaccares lagoon system, to... 
Tipo: Text 
Palavraschave: Coastal lagoon; Mathematical model; Hydrodynamics; Calibration; Validation; Winddriven circulation. 
Ano: 2015 
URL: http://archimer.ifremer.fr/doc/00303/41382/40558.pdf 
 


Ribas,Giovana Ghisleni; Streck,Nereu Augusto; Duarte Junior,Ary José; Ribeiro,Bruna San Martin Rolin; Pilecco,Isabela Bulegon; Rossato,Ioran Guedes; Richter,Gean Leonardo; Bexaira,Kelin Pribs; Pereira,Vladison Fogliato; Zanon,Alencar Junior. 
Abstract: The objective of this work was to model, in the SimulArroz model, the three floodirrigated rice (Oryza sativa) cultivars currently most grown in the state of Rio Grande do Sul, Brazil. The experiments to calibrate and validate the model were conducted in the municipalities of Cachoeirinha, Santa Maria, Uruguaiana, Santa Vitória do Palmar, and Cachoeira do Sul during four crop seasons. The number of leaves, phenology, aboveground dry matter biomass, and yield of each cultivar were evaluated. The results showed a slight overestimate of the R1, R4, and R9 stages; however, overall, the SimulArroz model had a good performance in simulating rice phenology for the three studied genotypes. Furthermore, the model had a reasonable accuracy in simulating... 
Tipo: Info:eurepo/semantics/article 
Palavraschave: Oryza sativa; Mathematical model; Yield. 
Ano: 2020 
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100204X2020000101001 
 


Lin,Yutian; Liu,Guoli; Lin,Huibin; Gao,Ling; Lin,Jianqiang. 
Background: Candida utilis is widely used in bioindustry, and its cell mass needs to be produced in a cost effective way. Process optimization based on the experimental results is the major way to reduce the production cost. However, this process is expensive, time consuming and labor intensive. Mathematical modeling is a useful tool for process analysis and optimization. Furthermore, sufficient information can be obtained with fewer experiments by using the mathematical modeling, and some results can be predicted even without doing experiments. Results: In the present study, we performed the mathematical modeling and simulation for the cell mass production of Candida utilis based on limited batch and repeated fedbatch experiments. The model parameters... 
Tipo: Journal article 
Palavraschave: Candida utilis; Fermentation; Genetic algorithm; Mathematical model. 
Ano: 2013 
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S071734582013000400002 
 

 

 


CABUCI, J. A.; EUCLYDES, R. F.; TEODORO, R. L.; VERNEQUE, R. da S.; LOPES, P. S.; SILVA, M. de A.. 
O conhecimento das relações genéticas entre os parâmetros da curva de lactação e a produção de leite é importante para a seleção de vacas e de touros. Os registros de produção de leite de 583 vacas da raça Guzerá, filhas de 165 reprodutores, foram usados para estimação dos parâmetros da curva de lactação em dois modelos matemáticos. As informações referentes às produções de leite foram obtidas usandose a base de dados extraída do Arquivo Zootécnico Nacional, mantido na Empresa Brasileira de Pesquisa Agropecuária (Embrapa Gado de Leite). As análises foram efetuadas usandose o sistema MTDFREML, sob modelo animal que incluiu os efeitos fixos de rebanhoanoestação de parto e, como covariável, a idade da vaca ao parto, com termos linear e quadrático. Como... 
Tipo: Artigo de periódico 
Palavraschave: Correlacoes geneticas; Metodo REML; Modelos Matematicos; Raca guzera; Genetic correlations; Guzera breed; Mathematical model; REML; Curva de Lactação; Lactation curve. 
Ano: 2001 
URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/594695 
 

 

 


Gallo,Sarita Bonagurio; Tedeschi,Luis Orlindo. 
ABSTRACT: Intake is a multifactorial process that is influenced by animal type, environmental factors, and diet characteristics. Sheep, especially, have specific eating habits, with a greater selection of ingested feed compared to cattle. Thus, predictive equations for dry matter intake (DMI) must constantly be reviewed. The objective of this study was to combine different adjustment factors to develop one continuous adjustment factor for predicting the DMI of pregnant, dry, and lactating ewes. The equations evaluated for nonlactation ewes accounts for metabolic body weight and weight gain, and the equation for lactating ewes includes milk production and its fat content. The database used in this study was pooled from hair sheep ewes, two to four years... 
Tipo: Info:eurepo/semantics/article 
Palavraschave: Mathematical model; Nutrition model; Prediction; Requirement; Sheep. 
Ano: 2021 
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S010390162021000200502 
 

 

 


Carvalho,Webber Tavares de; Oliveira,Tatianne Ferreira de; Silva,Flávio Alves da; Caliari,Márcio; Soares Júnior,Manoel Soares. 
Potato pulp waste (PPW) drying was investigated under different experimental conditions (temperatures from 50 to 70 °C and air flow from 0.06 to 0.092 m³ m 2 s 1) as a possible way to recover the waste generated by potato chip industries and to select the bestfit model to the experimental results of PPW drying. As a criterion to evaluate the fitting of mathematical models, a method based on the sum of the scores assigned to the four evaluated statistical parameters was used: regression coefficient (R²), relative mean error P (%), root mean square error (RMSE), and reduced chisquare (χ²). The results revealed that temperature and air velocity are important parameters to reduce PPW drying time. The models Midilli and Diffusion had the lowest sum values,... 
Tipo: Info:eurepo/semantics/article 
Palavraschave: Solanum tuberosum L.; Recovery of byproducts; Processing; Mathematical model. 
Ano: 2014 
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S010120612014000100017 
 

 


Lima,Ernesto A B F; Ferreira,Claudia P; Godoy,Wesley A C. 
Ecological modeling is an important tool for investigating dynamic behavior patterns in populations, trophic interactions, and behavioral ecology. However, the ecological patterns that reflect population oscillation trends are often not clearly visible without analytical instruments such as ecological models. Thus, ecological modeling plays a fundamental role in describing demographic processes that are important for population dynamics. Ecological models, besides making possible the visualization of ecological patterns, may also reveal patterns of population persistence in many trophic systems, including preypredator or hostparasitoid relationships, interactions that are commonly present in integrated pest management programs. In this forum, we present... 
Tipo: Info:eurepo/semantics/article 
Palavraschave: Theoretical ecology; Integrated pest management; Mathematical model. 
Ano: 2009 
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1519566X2009000600001 
 

 


Nival, Paul; Malara, G.. 
Choosing the best conditions for the cultivation of plankton in tanks is a difficult deal, which is generally solved by means of subjective estimations. A better way of looking for these conditions is the use of a mathematical model. _ We have tried to built a model that accounts for the physical and biological characteristics of the tanks. The data concerning the physiological characteristics of the different group of organisms encountered are too scarce to allow all of them to be taken into account. The system studied here is composed of nutrients, phytoplankton, herbivorous copepods and rotifers to which benthic algae have been added. With the hypothesis of 3 elements (phyto  zooplankton  nutrients) it can be showed that when an equilibrium is... 
Tipo: Text 
Palavraschave: Phytoplancton; Zooplancton; Culture; Modèle mathématique; Phytoplankton; Zooplankton; Culture; Mathematical model. 
Ano: 1979 
URL: http://archimer.ifremer.fr/doc/00306/41673/40882.pdf 
 


Szesz Junior,Albino; Monteiro Junior,Marcos; Dias,Ariangelo Hauer; Mathias,Ivo Mário; Conti,Giuvane. 
ABSTRACT: Aeration is currently the most commonly used technique to improve the drying and storage of grain, depending on temperature and water content of the grain, as of the temperature and relative humidity of the outside air. In order to monitor temperature and humidity of the grain mass, it is possible to have a network of sensors in the cells of both internal and external storage. Use of artificial intelligence through Fuzzy theory, has been used since the 60s and enables their application on various forms. Thus, it is observed that the aeration of grain in function of representing a system of controlled environment can be studied in relation to the application of this theory. Therefore, the aim of this paper is to present an embedded Fuzzy control... 
Tipo: Info:eurepo/semantics/article 
Palavraschave: Arduino; Agriculture; Mathematical model; Fuzzy logic; Grain aeration. 
Ano: 2016 
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S010384782016001101917 
 
Registros recuperados: 60  


