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Fractal analysis of agricultural nozzles spray Scientia Agricola
Agüera,Francisco; Nuyttens,David; Carvajal,Fernando; Sánchez-Hermosilla,Julián.
Fractal scaling of the exponential type is used to establish the cumulative volume (V) distribution applied through agricultural spray nozzles in size x droplets, smaller than the characteristic size X. From exponent d, we deduced the fractal dimension (Df) which measures the degree of irregularity of the medium. This property is known as 'self-similarity'. Assuming that the droplet set from a spray nozzle is self-similar, the objectives of this study were to develop a methodology for calculating a Df factor associated with a given nozzle and to determine regression coefficients in order to predict droplet spectra factors from a nozzle, taking into account its own Df and pressure operating. Based on the iterated function system, we developed an algorithm...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Pesticides application; Modeling.
Ano: 2012 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162012000100002
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Simulação do crescimento do capim Tanzânia irrigado com base na unidade fototérmica, na adubação nitrogenada e na disponibilidade hídrica do período - doi: 10.4025/actasciagron.v33i2.4901 Agronomy
Almeida, Alexsandro Claudio dos Santos; UNIVERSIDADE DE SÃO PAULO; Mingoti, Rafael; USP; Coelho, Rubens Duarte; USP; Lourenço, Leandro Fellet; USP.
A modelagem da produção de forragem com o uso de unidades fototérmicas (UF) foi utilizada com sucesso nos capins elefante cv. Napier, Tanzânia e Brachiaria em condições ótimas de adubação e disponibilidade hídrica. Havendo a necessidade de modelos de produção de forragens para diferentes níveis de adubação e de irrigação. Nesse sentido, o objetivo deste trabalho é propor modelos para o capim Tanzânia (Panicum maximum Jacq. cv Tanzânia) sob diferentes lâminas de irrigação (25, 50,75, 100 e 125% da ETc) e adubação nitrogenada em diferentes localidades do Brasil, a partir de unidades fototérmicas. Os modelos foram ajustados para as doses de 0, 30, 60, 110 e 270 kg de N ha-1, doses divididas em aplicações após cada corte, com um ciclo de 35 dias de descanso....
Tipo: Pesquisa em ambiente controlado Palavras-chave: Agronomia; Engenharia rural; Irrigação e Drenagem Otimização; Modelagem; Irrigação irrigação e drenagem Optimization; Modeling; Irrigation.
Ano: 2011 URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/4901
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Estimating soybean yields with artificial neural networks Agronomy
Alves, Guiliano Rangel; Teixeira, Itamar Rosa; Melo, Francisco Ramos; Souza, Raniele Tadeu Guimarães; Silva, Alessandro Guerra.
 The complexity of the statistical models used to estimate the productivity of many crops, including soybeans, restricts the use of this practice, but an alternative is the use of artificial neural networks (ANNs). This study aimed to estimate soybean productivity based on growth habit, sowing density and agronomic characteristics using an ANN multilayer perceptron (MLP). Agronomic data from experiments conducted during the 2013/2014 soybean harvest in Anápolis, Goiás State, B razil, were used to conduct this study after being normalized to an ANN-compatible range. Then, several ANNs were trained to choose the best-performing one. After training the network, a performance analysis was conducted to select the ANN with a performance most appropriate for the...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Agronomia; Biometria modelagem e estatística Glycine max (L.) Merrill; Agronomic characteristics; Modeling; MLP; Perceptron. Produção vegetal.
Ano: 2018 URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/35250
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Estimating soybean yields with artificial neural networks Agronomy
Alves, Guiliano Rangel; Teixeira, Itamar Rosa; Melo, Francisco Ramos; Souza, Raniele Tadeu Guimarães; Silva, Alessandro Guerra.
 The complexity of the statistical models used to estimate the productivity of many crops, including soybeans, restricts the use of this practice, but an alternative is the use of artificial neural networks (ANNs). This study aimed to estimate soybean productivity based on growth habit, sowing density and agronomic characteristics using an ANN multilayer perceptron (MLP). Agronomic data from experiments conducted during the 2013/2014 soybean harvest in Anápolis, Goiás State, B razil, were used to conduct this study after being normalized to an ANN-compatible range. Then, several ANNs were trained to choose the best-performing one. After training the network, a performance analysis was conducted to select the ANN with a performance most appropriate for the...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Glycine max (L.) Merrill; Agronomic characteristics; Modeling; MLP; Perceptron.; Produção vegetal.
Ano: 2018 URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/35250
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REFERENCE EVAPOTRANSPIRATION FORECASTING BY ARTIFICIAL NEURAL NETWORKS REA
Alves,Walison B.; Rolim,Glauco de S.; Aparecido,Lucas E. de O..
ABSTRACT: Evapotranspiration (ET) is the main component of water balance in agricultural systems and the most active variable of the hydrological cycle. In the literature, few studies have used the forecast the day before via Artificial Neural Networks (ANNs) for the northern region of São Paulo state, Brazil. Therefore, this aimed to predict the reference evapotranspiration for Jaboticabal, the major sugarcane-producing region of São Paulo state. We used a historical series of data on average air temperature, wind speed, net radiation, soil heat flux, and daily relative humidity from 2002 to 2012, for Jaboticabal, SP (Brazil). ET was estimated by Penman-Monteith method. To forecast reference evapotranspiration, we used a feed-forward Multi-Layer...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Modeling; Multi-Layer Perceptron; Air temperature; Estimate.
Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162017000601116
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SIMULATION OF SODIUM AND POTASSIUM DYNAMICS BY THE HYDRUS 2D MODEL IN A HAPLIC PLANOSOL VIA RESIDUE WATER REA
Andrade,Carolyne W. L. de; Montenegro,Suzana M. G. L.; Miranda,Jarbas H. de; Montenegro,Abelardo A. de A.; Assis,Fred M. C. V. de.
ABSTRACT The application of chemical substances to the soil together with little attention given to the possible environmental impacts, transformed the environment into a recipient of waste. The aim of this study was to simulate the movement of water and solutes (sodium and potassium together) using the STANMOD and HYDRUS-2D models in a typical Haplic Planosol under the application of wastewater via surface irrigation under different flow rates. The experiment was conducted in the laboratory by miscible displacement tests, first using columns with deformed soil under saturation and steady water flow conditions, at a rate of 11.7 cm3 min-1, to obtain transport parameters of sodium and potassium ions, and in the applied residual water, the values of 475 and...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Modeling; Nutrients; Soil physical properties; Water reuse.
Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162018000600874
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Agricultural zoning of climate risk for Physalis peruviana cultivation in Southeastern Brazil PAB
Aparecido,Lucas Eduardo de Oliveira; Batista,Rafael Madureira; Moraes,José Reinaldo da Silva Cabral de; Costa,Cícero Teixeira Silva; Moraes-Oliveira,Adriana Ferreira de.
Abstract: The objective of this work was to elaborate the agricultural zoning of climatic risk (ZARC) for Physalis peruviana, through the thermal and water requirements of the crop in Southeastern Brazil. Air temperature (TAIR) and precipitation (PYEAR) data from 1,530 meteorological stations covering the entire region were used. Regions were considered climatically favorable to Physalis peruviana when TAIR was between 13 and 18ºC and PYEAR between 1,000 and 2,000 mm per year. Regions where TAIR was above 30ºC or less than 13ºC were considered inapt. Maps were created with this information and used to identify climatic characteristics and to establish the agricultural aptitude classes, termed apt, inapt, and marginal for the cultivation of Physalis...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Climate risk; Agrometeorology; Modeling; Big data.
Ano: 2019 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2019000100900
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Increasing yoghurt daily production with modeling and simulation process Ciência Rural
Araújo,Adolfo Vicente; Queiroz,Daniel Marçal de; Arcanjo,Gemima Santos; Dias,Santos Henrique Brant; Alves,Renato Martins; Pinto,Francisco de Assis de Carvalho; Valente,Domingos Sárvio Magalhães.
ABSTRACT: The objective of this research was to use the modeling and computer simulation to support decision makers, aiming to increase the productive capacity of the agro-industry of LaticínioFunarbe. Specifically, it has modeled the current yoghurt production sector for simulation that enables it to meet the new demand. The Arena 14.7 simulation software was used to conduct the modeling. To validate the model, the output of yoghurt production collected at the factory for three months was compared with the output from the simulated computational model. Two indicators were established to perform analyzes of four different scenarios. The implemented model resulted in an increase in the production capacity of 5,000L.d-1 of yoghurt, corresponding to a...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Modeling; Computer simulation; Cenario analysis; Yoghurt; Dairy industry.
Ano: 2019 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782019000100751
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Application of the Response Surface Method in the Analysis of Ohmic Heating Process Performance in Sour Orange Juice Processing CIGR Journal
Azadbakht, Mohsen; Vahedi Torshizi, Mohammad; Kashaninejad, Mahdi.
Three voltage gradients (8.38, 10.83, and 13.33 V cm-1) and three weight loss percentages (10, 20, and 30 percent) were examined; also the system performance coefficient, input current, heating process duration, power consumption and electrical conductivity investigated. The response surface method was also used for modeling s and optimization. For the response surface method, weight loss percentage and voltage gradient were selected as independent variables; and factors  system performance coefficient, heating process duration, input current, power consumption and electrical conductivity were selected as responses. According to results, all obtained models were significant for responses factors, but the voltage gradient and weight loss percentage were...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Sour orange juice; Ohmic method; Response surface method; Modeling.
Ano: 2020 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/6057
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Foam-mat drying of shrimp: characterization and drying kinetics of foam CIGR Journal
Azizpour, Mehran; Mohebbi, Mohebbat; Khodaparast, Mohammad Hossein Haddad; Varidi, Mehdi.
The effects of water: shrimp ratio and xanthan gum (XG) concentration on characteristics of shrimp foam were investigated.  Foams were prepared from shrimp puree by adding several xanthan gum concentrations (0.1, 0.2, 0.3 % w/w), water: shrimp ratios (2:1, 3.5:1, 5:1 w/w) and whipped for five minutes.  Incorporation of 0.2% w/w XG with 3.5:1 w/w water: shrimp ratio was selected because of having better characteristics of produced foams and then dried at 50, 60 and 70°C.  Results showed that stability and density of foam increased with increasing xanthan gum concentration.  However, increasing water : shrimp ratio caused to decrease in stability and density of foam.  As the temperature increased from 50 to 70°C, the drying time decreased to 55 minutes....
Tipo: Info:eu-repo/semantics/article Palavras-chave: Activation energy; Effective diffusivity; Foam-mat drying; Foam characteristics; Modeling; Shrimp.
Ano: 2013 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/2339
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A methology for the stocks assessments of cultivated oysters among along the French Atlantic coasts ArchiMer
Bacher, Cedric; Baud, Jean-pierre; Bodoy, Alain; Deslous-paoli, Jean-marc; Dreno, Jean-paul; Heral, Maurice; Maurer, Daniele; Prou, Jean.
An assessment of the reared stocks of the Pacific oyster (Crassostrea gigas ) has been recently conducted on the major French areas of molluscs culture. The methodology proposed included both estimates of densities obtained by subsampling in the field, and aerial photographs which covered the cultivated, intertidal area. The size and the number of samples were designed to reach a precision of 10% on the final assessment in each area. The field work consisted in weighing and counting the oyster in unit areas of 0.5 m2 for the bottom culture or in trays or bags, for the off bottom technique. These results give a better knowledge of the technique evolution and of the general structures in the cultivated areas.
Tipo: Text Palavras-chave: Modeling; Estimation; Stocks; Crassostrea gigas; Oysters.
Ano: 1986 URL: http://archimer.ifremer.fr/doc/1986/acte-2864.pdf
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Spatial, Ecological and Social Dimensions of Assessments for Bivalve Farming Management ArchiMer
Bacher, Cedric; Gangnery, Aline; Cugier, Philippe; Mongruel, Remi; Strand, Oivind; Frangoudes, Katia.
The general purpose of assessment is to provide decision-makers with the best valuable data, information, and predictions with which management decisions will be supported. Using case studies taken from four scientific projects and dealing with the management of marine bivalve resources, lessons learned allowed identifying some issues regarding assessment approaches. The selected projects also introduced methodological or institutional frameworks: ecosystem approach to aquaculture (EAA), system approach framework (SAF), marine spatial planning (MSP), and valuation of ecosystem services (ES). The study on ecosystem services linked ES to marine habitats and identified ES availability and vulnerability to pressures. The results were displayed as maps of...
Tipo: Text Palavras-chave: Ecosystem services; Marine spatial planning; Ecosystem approach to aquaculture; System approach; Modeling; Stakeholder involvement.
Ano: 2019 URL: https://archimer.ifremer.fr/doc/00470/58138/60608.pdf
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Dissolved Radiotracers and Numerical Modeling in North European Continental Shelf Dispersion Studies (1982–2016): Databases, Methods and Applications ArchiMer
Bailly Du Bois, Pascal; Dumas, Franck; Voiseux, Claire; Morillon, Mehdi; Oms, Pierre-emmanuel; Solier, Luc.
Significant amounts of anthropogenic radionuclides were introduced in ocean waters following nuclear atmospheric tests and development of the nuclear industry. Dispersion of artificial dissolved radionuclides has been extensively measured for decades over the North-European continental shelf. In this area, the radionuclide measurement and release fluxes databases provided here between 1982 and 2016 represent an exceptional opportunity to validate dispersion hydrodynamic models. This work gives accessibility to these data in a comprehensive database. The MARS hydrodynamic model has been applied at different scales to reproduce the measured dispersion in realistic conditions. Specific methods have been developed to obtain qualitative and quantitative results...
Tipo: Text Palavras-chave: Radionuclide; Tracer; Data collection; Antimony 125 (Sb-125); Tritium (H-3); Dispersion; Modeling; English Channel; North Sea; Biscay Bay.
Ano: 2020 URL: https://archimer.ifremer.fr/doc/00633/74521/74348.pdf
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Continuous fluorescence recording as a way to improve Pacific oyster (Crassostrea gigas) models of paralytic shellfish toxin accumulation ArchiMer
Baron, Regis; Couedel, Marielle; Joret, Camille; Garen, Pierre; Truquet, Philippe; Masselin, Pierre; Bardouil, Michele; Lassus, Patrick.
A simple system was used to simulate the effect of alternating toxic (paralytic shellfish poisoning toxins) and non-toxic microalgal diets on oyster feeding behaviors and rates of toxin accumulation. These experimental conditions were meant to reflect, to some extent, the incoming and outgoing fluxes of toxic algae observed at the mouth of the Penze estuary (Northern Brittany, France). Physiological and toxicological parameters were estimated based oil fluorescence measurements recorded continuously at the outlet of each experimental tank, which contained a single oyster. Q(tox), this variable describes toxin uptake in oysters, it was used (instead of the toxin ingestion rate): i) in simple graphical analyses, ii) as well as in one- and two-compartment...
Tipo: Text Palavras-chave: Skeletonema costatum; Alexandrium minutum; Fluorescence; Modeling; Kinetics; Toxin uptake; Shellfish toxin; PSP.
Ano: 2006 URL: http://archimer.ifremer.fr/doc/2006/publication-1400.pdf
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On Nature, Models, and Simplicity Ecology and Society
Baumann, Michael; University of British Columbia and ananature.com Scientific Services; baumann@interchange.ubc.ca.
Tipo: Peer-Reviewed Reports Palavras-chave: Complexity; Epistemology; Modeling; Simplicity.
Ano: 2000
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Simulation and economic analysis of bovine sex selection R. Bras. Zootec.
Beltrame,Renato Travassos; Quirino,Celia Raquel; Barioni,Luís Gustavo; Lima,Vera Fernanda Martins Hossepian de.
A simulation model implemented in the programming software Delphi XE® was applied to evaluate sex selection in bovine. The hypothesis under investigation was that a dynamic model with stochastic and deterministic elements could detect the sexed semen technique to minimize pregnancy cost and to determine the adequate number of recipients required for in vivo (ET) and in vitro embryo production (IVP) in the proposed scenarios. Sex selection was compared through semen sexed using flow cytometry (C1) and density gradient centrifugation techniques (C2) in ET and IVP. Sensibility analyses were used to identify the adequate number of recipients for each scenario. This number was reinserted into the model to determine the biological and financial values that...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Beef cattle; In vitro fertilization; Modeling; Stochastic simulation.
Ano: 2013 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982013000500003
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Measuring Competition between Non-Food and Food Demand on World Grain Markets : Is Biofuel Production Compatible with Pressure for Food Production ? AgEcon
Benjamin, Catherine; Houee-Bigot, Magalie.
The flow of agricultural products between countries is conditioned by several factors including domestic and trade policy tools for the main competing exporters countries, and macroeconomic variables (such as real income per capita, rate of population growth,etc). Important structural changes are occurring on world agricultural markets that will have an impact on the long term competitiveness of countries and regions. These changes include developments in biofuels production linked to policy incentives, and the rapid growth in income and population numbers in some developing countries (such as India and China). An important issue is to identify the factors that are going to modify the balance between the supply and demand for agricultural products in the...
Tipo: Conference Paper or Presentation Palavras-chave: Modeling; Econometric; Partial equilibrium; Land uses; Biofuels; Demand and Price Analysis; International Relations/Trade.
Ano: 2007 URL: http://purl.umn.edu/9854
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Modelo de balanço de nitrogênio para a cana-de-açúcar fase II - construção de modelo software STELLA. Infoteca-e
BERGAMASCO, A. F.; SILVA, F. C. da; RODRIGUES, L. H. A.; TRIVELIN, P. C. O..
A cultura da cana-de-açúcar vem sofrendo mudanças, de âmbitos tecnológicos e sociais, profundas nesta década, procurando se adaptar às demandas de produção com alta produtividade, competitividade e respeito ao meio ambiente. Apesar de o Brasil ser o maior produtor mundial de cana-de-açúcar, ainda pratica a queima da palha do canavial para facilitar a colheita, o que gera prejuízos econômicos, sociais e ambientais. Sem essa queima (Decreto n.° 42056 do Estado de SP), a cobertura do solo pela palhada irá provocar significativas mudanças no manejo da cultura e na dinâmica do nitrogênio. Dada a complexibilidade do ciclo de nitrogênio no solo, seus vários caminhos de transformação, e as variações climáticas, é difícil a determinação do melhor manejo do...
Tipo: Boletim de Pesquisa e Desenvolvimento (INFOTECA-E) Palavras-chave: Cana-de-açucar; Adubação nitrogenda; Software ESTELLA; Modelagem matemática; Modeling; Sugar cane.; Modelo Matemático..
Ano: 2002 URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/8690
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The Gulf of Lions: An overview of recent studies within the French 'Margins' Programme ArchiMer
Berne, Serge; Gorini, C.
Within the French 'Margins' Programme (Groupement de Recherches 'Marges', or 'GDR Marges'), The Gulf of Lions was selected as a key area where scientists specialized in complementary aspects of geosciences (structural geology, tectonics, stratigraphy, sedimentology, various aspects of modeling) work together in order to better understand the processes that control the formation and evolution of continental margins. A key objective was to link offshore data (that mainly consist of seismic data and few wells) and onshore studies (mainly based on well and field data). This special edition of Marine and Petroleum Geology on the Gulf of Lions presents some of the main results obtained during three years of research by the group 'GDR Marges-Golfe du Lion'.
Tipo: Text Palavras-chave: Modeling; Geosciences; 'Margins' Programme; Gulf of Lions.
Ano: 2005 URL: http://archimer.ifremer.fr/doc/2005/publication-728.pdf
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Validation study of an overall radiation balance estimation method under Ponta Grossa (PR) Brazil weather conditions REA
Beruski,Gustavo C.; Pereira,André B..
Radiation balance is the fraction of incident solar radiation upon earth surface which is available to be used in several natural processes, such as biological metabolism, water loss by vegetated surfaces, variation of temperature in farming systems and organic decomposition. The present study aimed to assess and validate the performance of two estimation models for Rn in Ponta Grossa city, Paraná State, Brazil. To this end, during the period of 04/01/2008 to 04/30/2011, from radiometric data collected by an automatic weather station set at the Experimental Station, of the State University of Ponta Grossa. We performed a linear regression study by confrontation between measurements made through radiometric balance and Rn estimates obtained from Brunt...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Overall radiation balance; Bowen ratio; Global solar radiation; Modeling; Solar radiometry.
Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162014000300010
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