


Registros recuperados: 147  

 

 

 

 

 

 


GaleanoVasco,Luis Fernando; CerónMuñoz,Mario Fernando; NarváezSolarte,William. 
In this study, the Von Bertalanffy, Richards, Gompertz, Brody, and Logistics nonlinear mixed regression models were compared for their ability to estimate the growth curve in commercial laying hens. Data were obtained from 100 Lohmann LSL layers. The animals were identified and then weighed weekly from day 20 after hatch until they were 553 days of age. All the nonlinear models used were transformed into mixed models by the inclusion of random parameters. Accuracy of the models was determined by the Akaike and Bayesian information criteria (AIC and BIC, respectively), and the correlation values. According to AIC, BIC, and correlation values, the best fit for modeling the growth curve of the birds was obtained with Gompertz, followed by Richards, and then... 
Tipo: Info:eurepo/semantics/article 
Palavraschave: Chickens; Mathematical models; Poultry; Regression analysis; Weight gain. 
Ano: 2014 
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S151635982014001100573 
 


Laxminarayan, Ramanan. 
In the past, malaria control efforts in subSaharan Africa have relied on a combination of vector control and effective treatment using chloroquine. With increasing resistance to chloroquine, attention has now turned to alternative treatment strategies to replace this failing drug. Although there are strong theoretical arguments in favor of switching to more expensive artemisininbased combination treatments (ACTs), the validity of these arguments in the face of financial constraints has not been previously analyzed. In this paper, we use a Bioeconomic model of malaria transmission and evolution of drug resistance to examine questions of optimal treatment strategy and coverage when drug resistance places an additional constraint on choices available to the... 
Tipo: Working or Discussion Paper 
Palavraschave: Malaria; Mathematical models; Drug resistance; Bioeconomics; Health Economics and Policy; I10; I19; C61. 
Ano: 2003 
URL: http://purl.umn.edu/10699 
 


Le Berre, Jerome. 
Introduction: This document is the End of Second Year internship report for Rennes University 1's Senior Math and Computer Science Modelisation Professional diploma. This two month internship was completed at the Brest IFREMER center at the Coastal Ecology department. IFREMER participates, in the course of its institutional missions, in observation and coastal sea surveillance, in order to improve on the knowledge, protection methods and restoration of the marine environment. Marine phytoplankton proliferation is an important study subject because of its potential cause for nuisance, for men, consumers of sea products as well as for the ecosystem. During Spring and Summer, shellfish become invariably unsuitable for consumption due to toxins produced by... 
Tipo: Text 
Palavraschave: Aquaculture; Growth; Phytoplanctonic algae; Mathematical models. 
Ano: 2000 
URL: http://archimer.ifremer.fr/doc/2000/rapport1770.pdf 
 


Velázquez Castro, Gilberto David. 
Para complementar los servicios de información a empresas o personas físicas, en cuanto a comunicar, no sólo cambios en sus variables de interés, sino el impacto que éstos tienen sobre las actividades de la empresa, se propone un servicio que calcula tales impactos con el uso de modelos matemáticos. Se puede generar una alarma al cliente, cuando los cambios satisfagan criterios que éste define para tal efecto. De acuerdo a la urgencia indicada, se comunicará al cliente por correo electrónico, mensaje de texto o una llamada de un empleado del servicio, alguna situación que pudiera requerir una decisión oportuna.______A service to customers was conceived in order to offer information about the impact of changes in their data, rather than just report... 
Tipo: Tesis 
Palavraschave: Comunicación oportuna; Interpretable; Modelos matemáticos; Alarmas; Datos del entorno empresarial; Maestría; Computo Aplicado; Timely communicaction; Interpretable; Mathematical models; Alarms; Business environment data. 
Ano: 2009 
URL: http://hdl.handle.net/10521/1505 
 

 

 


Aubone, A.; Wöhler, O.C.. 
With the purpose of easening its application, the theory of parameter estimation by the maximum likelihood method is presented. The theory is general and useful for linear and nonlinear models. The method is applied to the von Bertalanffy´s growth model for individual data and for mean values of lengthatage. Statistical tests to compare parameters from different population groups are presented. Problems caused by lack of verification of assumptions are discussed. An example of its application is given and results of nonlinear least squares estimations are compared to those obtained with Allen´s method. An example of application implemented on a calculus spreadsheet is attached. 
Tipo: Journal Contribution 
Palavraschave: Growth curves; Mathematical models; Mathematical models; Http://aims.fao.org/aos/agrovoc/c_24199. 
Ano: 2000 
URL: http://hdl.handle.net/1834/2541 
 

 


Clemente,Edmar; Afonso,Marcos Rodrigues Amorim; Souza,Ana Paula; Correia,José Maria; Pires,Raquel Gomes; Maia,Geraldo Arraes. 
Solid mixtures for refreshment are already totally integrated to the Brazilian consumers' daily routine, because of their quick preparation method, yield and reasonable price  quite lower if compared to 'readytodrink' products or products for prompt consumption, what makes them economically more accessible to lowincome populations. Within such a context, the aim of this work was to evaluate the physicochemical and mineral composition, as well as the hygroscopic behavior of four different brands of solid mixture for mango refreshment. The BET, GAB, Oswim and Henderson mathematical models were built through the adjustment of experimental data to the isotherms of adsorption. Results from the physiochemical evaluation showed that the solid mixtures for... 
Tipo: Info:eurepo/semantics/article 
Palavraschave: Adsorption; Isotherms; Mathematical models; Nutritious powders; Refreshment; Mango. 
Ano: 2011 
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S010120612011000300010 
 

 


Lima,Máida Cynthia Duca de; BarretoGarcia,Patrícia Anjos Bittencourt; Sanquetta,Carlos Roberto; Novaes,Adalberto Brito de; Melo,Lara Clímaco de. 
ABSTRACT: There is a large number of studies evaluating methods to quantify biomass for the genus Pinus in different regions of Brazil. However, knowledge about this subject in the Northeast region of Brazil is still incipient. The objective of the present study was to assess the biomass and carbon stocks and select mathematical models to estimate these variables in Pinus caribaea var. hondurensis , which is established in homogenous stands in the Southwest region of the state of Bahia (Brazil). The biomass was quantified using the destructive method. Samples of needles, bole, bark, and branches were analyzed to determine their carbon contents. Ten models were tested, and the best of them were chosen based on the following statistical indicators: adjusted... 
Tipo: Info:eurepo/semantics/article 
Palavraschave: Exotic forest species; Mathematical models; Biomass. 
Ano: 2016 
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S010384782016000600957 
 

 

 
Registros recuperados: 147  


