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A Mathematical Model for the Removal of Organic Mater in Stabilization Ponds BABT
Medri,Waldir; Medri,Vandir.
This work presents an application to systemize the construction of ponds systems for treatment of domestic sewage. It consisted of two anaerobic ponds operated in parallel during May/97 to April/99. These were connected in series with a chicaned facultative pond. The treatment system was controlled with samples collected from the crude sewage (compound sample), in the affluents and effluents of the ponds and along the flux of the anaerobic and facultative ponds. The following parameters were analyzed: pH, Biochemical Oxygen Demand, Chemical Oxygen Demand, Total Solids, Sedimentable Solids, Total Coliforms, Oxygen Consumed in Acid Medium (OCAM) and temperature.
Tipo: Info:eu-repo/semantics/article Palavras-chave: Stabilization ponds; Mathematical model; Optimization.
Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132002000100014
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A mathematical model to estimate the volume of grey water of pesticide mixtures. Repositório Alice
PARAIBA, L. C.; PAZIANOTTO, R. A. A.; LUIZ, A. J. B.; MAIA, A. de H. N.; JONSSON, C. M..
2013
Tipo: Artigo em anais de congresso (ALICE) Palavras-chave: Herbicida; Cana de açúcar; Modelo matemático; Sugarcane; Herbicides; Water footprint; Freshwater; Mathematical model.
Ano: 2013 URL: http://www.alice.cnptia.embrapa.br/handle/doc/970136
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A simple mathematical model to determine the ideal empirical antibiotic therapy for bacteremic patients BJID
Tuon,Felipe F.; Rocha,Jaime L.; Leite,Talita M.; Dias,Camila.
BACKGROUND: Local epidemiological data are always helpful when choosing the best antibiotic regimen, but it is more complex than it seems as it may require the analysis of multiple combinations. The aim of this study was to demonstrate a simplified mathematical calculation to determine the most appropriate antibiotic combination in a scenario where monotherapy is doomed to failure. METHODS: The susceptibility pattern of 11 antibiotics from 216 positive blood cultures from January 2012 to January 2013 was analyzed based on local policy. The length of hospitalization before bacteremia and the unit (ward or intensive care unit) were the analyzed variables. Bacteremia was classified as early, intermediate or late. The antibiotics were combined according to the...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Mathematical model; Infection; Antibiotic; Bacteremia.
Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-86702014000400360
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Acidez potencial pelo método do pH SMP no Estado do Amazonas . Repositório Alice
MOREIRA, A.; ALMEIDA, M.P. de; COSTA, D.G.; SANTOS, L.S..
O objetivo deste trabalho foi definir um modelo matemático que estime o H+Al a partir do pH SMP medido em água e em solução de CaCl2 0,01 mol L-1 nas condições edafoclimáticas locais. Foram utilizadas 246 amostras de solo provenientes de diversas localidades. Mesmo apresentando menor coeficiente da correlação (r = 0,89*), a equação H+Al = 30,646 - 3,848pH SMP obtida em H2O foi mais eficiente que a obtida em solução CaCl2 (H+Al = 30,155 - 3,834pH SMP, r = 0,91*), a qual subestima os valores da acidez potencial.
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Fator edáfico; Fator climático; Solução-tampão; Química do solo; Modelo matemático; Edaphic factors; Climatic factors; Buffer solution; Soil chemistry; Mathematical model.
Ano: 2004 URL: http://www.alice.cnptia.embrapa.br/handle/doc/106807
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Adjustment of growth models in broiler chickens PAB
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 first-order autocorrelated error structure. Weighted models and weighted autocorrelated error models showed different parameter values when compared with the unweighted models,...
Tipo: Info:eu-repo/semantics/article Palavras-chave: 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=S0100-204X2017001201241
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An Unstructured Numerical Model to Study Wind-Driven Circulation Patterns in a Managed Coastal Mediterranean Wetland: The Vaccares Lagoon System ArchiMer
Boutron, Olivier; Bertrand, Olivier; Fiandrino, Annie; Hoehener, Patrick; Sandoz, Alain; Cherain, Yves; Coulet, Eric; Chauvelon, Philippe.
The spatiotemporal structure of wind-driven circulation patterns and associated water exchanges can drive important bio-hydrodynamic 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 wind-driven circulations in the Vaccares lagoon system, to...
Tipo: Text Palavras-chave: Coastal lagoon; Mathematical model; Hydrodynamics; Calibration; Validation; Wind-driven circulation.
Ano: 2015 URL: http://archimer.ifremer.fr/doc/00303/41382/40558.pdf
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An update of new flood-irrigated rice cultivars in the SimulArroz model PAB
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 flood-irrigated 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:eu-repo/semantics/article Palavras-chave: Oryza sativa; Mathematical model; Yield.
Ano: 2020 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2020000101001
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Analysis of batch and repeated fedbatch productions of Candida utilis cell mass using mathematical modeling method Electron. J. Biotechnol.
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 Palavras-chave: Candida utilis; Fermentation; Genetic algorithm; Mathematical model.
Ano: 2013 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000400002
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Application of approximate formulae to analyse the spectral distribution of the light attenuation coefficient ArchiMer
Kopec, J; Pawlak, B.
An analysis is made of the spectral distribution curves of the light attenuation coefficient in natural water areas and artificial roily oils in sea water samples under various conditions of salinity and storage time, using the approximate formulae based on the Mie theory.
Tipo: Text Palavras-chave: Modèle mathématique; Coefficient d'atténuation de la lumière; Théorie de Mie; Mathematical model; Light attenuation coefficient; Mie theory.
Ano: 1998 URL: http://archimer.ifremer.fr/doc/00325/43647/43223.pdf
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Aprovechamiento de la humedad atmosférica como fuente no convencional de agua para uso doméstico. Colegio de Postgraduados
Bautista Olivas, Ana Laura.
En esta investigación se plantearon tres objetivos generales los cuales fueron: 1) Proponer un modelo matemático para predecir la cantidad de agua atmosférica que se puede obtener con el prototipo CP-HID-04 en la Ciudad de México considerando la humedad relativa del ambiente y temperatura ambiental; estos modelos se validaron calculando los siguientes índices: MBE (error medio), RMBE (raíz cuadrada del error cuadrático, D (Índice de acuerdo), R2 (coeficiente de determinación). 2) Cuantificar la cantidad de coliformes totales y fecales encontradas en muestras de agua atmosférica obtenidos en tres sitios de estudio: San Felipe Hidalgo, Tlaxcala; Huichapan, Hidalgo y en la Ciudad de México. 3) Evaluar la calidad del agua obtenida de la atmósfera,...
Palavras-chave: Agua atmosférica; Modelo matemático; Calidad de agua; Coliformes fecales; Metales pesados; Atmospheric water; Mathematical model; Water quality; Fecal coliform; Heavy metals; Hidrociencias; Doctorado.
Ano: 2013 URL: http://hdl.handle.net/10521/2008
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Avaliação do crescimento da agricultura amazônica. Infoteca-e
CARVALHO, R. de A.; FERREIRA, C. A. P.; HOMMA, A. K. O.; OLIVEIRA, R. P. de..
1994
Tipo: Documentos (INFOTECA-E) Palavras-chave: Desenvolvimento agrícola; Produção; Agricultura; Economia; Modelo matemático; Amazônia; Brasil; Agricultural development; Production; Agriculture; Economy; Mathematical model.
Ano: 1994 URL: http://www.infoteca.cnptia.embrapa.br/handle/doc/383671
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Avaliação do risco de contaminação da água subterrânea por agrotóxicos em Mato Grosso do Sul: efeito do clima e solo. Repositório Alice
SCORZA JUNIOR, R. P.; SIVIERI, F. H. C.; SEABRA, F. A. de S..
2016
Tipo: Artigo em anais de congresso (ALICE) Palavras-chave: Solo; Clima; Modelo matemático; Agrotóxico; Soil; Climate; Mathematical model; Agrotoxic; PEARL.
Ano: 2016 URL: http://www.alice.cnptia.embrapa.br/handle/doc/1059808
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Comparison of anaerobic threshold determined by visual and mathematical methods in healthy women BJMBR
Higa,M.N.; Silva,E.; Neves,V.F.C.; Catai,A.M.; Gallo Jr.,L.; Silva de Sá,M.F..
Several methods are used to estimate anaerobic threshold (AT) during exercise. The aim of the present study was to compare AT obtained by a graphic visual method for the estimate of ventilatory and metabolic variables (gold standard), to a bi-segmental linear regression mathematical model of Hinkley's algorithm applied to heart rate (HR) and carbon dioxide output (VCO2) data. Thirteen young (24 ± 2.63 years old) and 16 postmenopausal (57 ± 4.79 years old) healthy and sedentary women were submitted to a continuous ergospirometric incremental test on an electromagnetic braking cycloergometer with 10 to 20 W/min increases until physical exhaustion. The ventilatory variables were recorded breath-to-breath and HR was obtained beat-to-beat over real time. Data...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Anaerobic threshold; Incremental test; Graphic visual method; Mathematical model; Hinkley's algorithm.
Ano: 2007 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2007000400008
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Developing a continuous adjustment factor for dry matter intake of gestating and lactating ewes Scientia Agricola
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 non-lactation 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:eu-repo/semantics/article Palavras-chave: Mathematical model; Nutrition model; Prediction; Requirement; Sheep.
Ano: 2021 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162021000200502
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Development of a calculation model and production cost index for feedlot beef cattle R. Bras. Zootec.
Sartorello,Gustavo Lineu; Bastos,João Paulo Sigolo Teixeira; Gameiro,Augusto Hauber.
ABSTRACT The objective of this study was to develop a feedlot beef cattle calculation model and production cost analysis and, from the results obtained, devise a production cost index. A case study was conducted to understand the characteristics of the productive processes of a commercial feedlot. Then, based on the Economic Theory, cost items of the farm under analysis were identified and transferred to a spreadsheet. The survey included ten feedlot farmers from the state of São Paulo and other nine from the state of Goiás and was carried out to determine representative properties, and prices of items used were monitored. Production costs of each farm were calculated, and theoretical concepts of index numbers were used to devise the feedlot cattle...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Economic indicators; Economy; Livestock; Mathematical model; Production systems; Survey.
Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982018000100704
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Development of moisture isotherms for Momordica charantia and Carica papaya CIGR Journal
Rupasinghe, chintha Priyangani; Jayasinghe, Udara; Sugathapala, Thusitha.
Safe moisture of a product is important in drying of agricultural products to prevent it from deterioration. The equilibrium moisture content (EMC) is an important parameter in modeling and simulation of drying process. The objectives of the research are development of an EMC curve for Agricultural Products; bitter gourd (Momordica charantia) and papaya (Carica papaya) and to test the suitability of mathematical models of modified Henderson’s equations. The study is performed on the basis of adsorption of moisture content, at three temperatures (30, 40 & 50°C) and four relative humidity (Rh) (10, 30, 50 and 80%). Salt solutions with concentrations were used to maintain Rh. The statistical analysis was done to find the best model and the significant...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Post harvest technology Equilibrium moisture content; Adsorption; Isotherms; Mathematical model.
Ano: 2019 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/5114
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Drying kinetics of potato pulp waste Ciênc. Tecnol. Aliment.
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 best-fit 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 chi-square (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:eu-repo/semantics/article Palavras-chave: Solanum tuberosum L.; Recovery of by-products; Processing; Mathematical model.
Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-20612014000100017
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Dynamics of the control of Aedes (Stegomyia) aegypti Linnaeus (Diptera, Culicidae) by Bacillus thuringiensis var israelensis, related with temperature, density and concentration of insecticide Rev. Bras. entomol.
Duque L,Jonny E.; Navarro-Silva,Mario Antônio.
The dynamics of the control of Aedes (Stegomyia) aegypti Linnaeus, (Diptera, Culicidae) by Bacillus thuringiensis var israelensis has been related with the temperature, density and concentration of the insecticide. A mathematical model for biological control of Aedes aegypti with Bacillus thuringiensis var israelensis (Bti) was constructed by using data from the literature regarding the biology of the vector. The life cycle was described by differential equations. Lethal concentrations (LC50 and LC95) of Bti were determined in the laboratory under different experimental conditions. Temperature, colony, larvae density and bioinsecticide concentration presented marked differences in the analysis of the whole set of variables; although when analyzed...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Biological control; Environmental variable; Mathematical model.
Ano: 2006 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0085-56262006000400014
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Ecological modeling and pest population management: a possible and necessary connection in a changing world Neotropical Entomology
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 prey-predator or host-parasitoid relationships, interactions that are commonly present in integrated pest management programs. In this forum, we present...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Theoretical ecology; Integrated pest management; Mathematical model.
Ano: 2009 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1519-566X2009000600001
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Economic optimization of the number of recipients in bovine embryo transfer programs Scientia Agricola
Beltrame,Renato Travassos; Barioni,Luis Gustavo; Maestri,Breno Dala; Quirino,Celia Raquel.
Purchase and maintenance of recipient females account for a large proportion of the costs and determine the number of calves that can be produced in an embryo transfer program. However, the large variability of embryo production by the donors and the need to purchase and synchronize the recipients before knowing the number of embryos collected make it difficult for the decision maker to identify the ideal number of recipient females to allocate. An ex-ante evaluation to determine the optimal number of recipient females was carried out through a sensitivity analysis for the ratio between the number of recipients and donors in a simulation model. The variability for the number of embryos collected was accounted for by applying the Monte Carlo simulation...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Monte Carlo; Mathematical model; Simulation; Cost estimation; Estrus synchronization.
Ano: 2007 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162007000300002
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