Aplicação de modelos matemáticos bi e tri-paramétricos na predição de isotermas de adsorção de umidade do guaraná (Paullinia cupana) em pó

Doze modelos matemáticos (seis bi-paramétricos e seis tri-paramétricos), amplamente utilizados na predição de isotermas, foram estudados, com o objetivo de predizer isotermas de adsorção de umidade do guaraná (Paullinia cupana) em pó, obtido em "sprey dryer". As isotermas de adsorção de umidade do produto à 15° C, 25° C e 35° C, foram ajustadas por análise de regressão não-linear, usando o aplicativo STATGRAPHICS 5.1. Entre os modelos testados os que apresentaram melhores resultados nos ajustes foram as equações tri-paramétricas de GAB, BET modificada e Anderson, e as equações bi-paramétricas de Handerson e Oswin.

Análise crítica de produção científica no tema de modelos matemáticos em dengue

Analisa-se diferentes aspectos da epidemiologia da transmissão da dengue através de modelos matemáticos. Supo˜e-se que o controle vetorial atua como uma taxa de mortalidade adicional em cada fase do ciclo de vida do mosquito Ae. aegypti e estuda-se a eficiência dos diferentes mecanismos utilizados pela Superintendência de Controle de Endemias (SUCEN) no estado de São Paulo para o controle da doença. A modelagem usual de equações diferencias ordinárias (EDO) permite a obtenção de valores limiares para a taxa de oviposição do vetor e para a transmissão da doença, as quais depende das suposições biológicas que geram o modelo, dos parâmetros entomológicos do mosquito, do período de incubação do vírus, e da imunidade e dinâmica vital do homem. Estes limiares dividem o espaço de solução em ausência do vetor, presença do vetor e ausência de transmissão da dengue, e presença do vetor com transmissão da dengue. Estes valores fornecem uma estimativa do esforço de controle necessário para diminuir ou parar a transmissão da dengue. A suposição de população vetorial grande com distribuição espacial homogênea (modelos de equações diferencias ordinárias discutidos anteriormente) é verificada através da modelagem discreta de autômatos celulares (AC). Mostra-se que a heterogeneidade espacial gerada pela distribuição de criadouros facilita a colonização e dispersão do inseto. Como os parâmetros entomológicos do vetor dependem da temperatura, observa-se que no verão o processo de dispersão e colonização do mosquito é facilitado, e que o controle adulticida deve ser aplicado nesta época. Já no inverno deve-se investir no controle das formas imaturas. A viabilidade da técnica de insetos estéries é...

Comportamento caótico em modelos matemáticos de câncer

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Análise e simulação de modelos matemáticos para a estimativa da geração de gases em bioprocessos de decomposição anaeróbia de resíduos sólidos em aterros sanitários

Brazil faces a complex problem in respect to municipal solid waste, having been in recent years an increase of its generation without the country there be adequate for proper disposal thereof. In many states , the percentage of waste destined improperly , ie , in dumps , landfills, send- outs , among others , is greater than that disposed in landfills , which would be the most correct way to be made. It can be argued that this discrepancy is due to the high cost of implementation and operation of the landfill, and the same need large areas with physical characteristics that suit their operations . When there is a provision in properly constructed landfills , municipal solid waste grounded generate gases with high potential energy through biochemical reactions during the anaerobic decomposition of organic material stored . Such gases can be used for power generation within the landfill or other economic means . To estimate the gas generation will be sufficient for such economic compensation , there are mathematical models that make estimating the amount of gas produced . These models calculate the energy capacity and generation , using parameters obtained based on the characteristics of solid waste , climate of the region where they are grounded and grounding time . Such models have been raised and studied so that it was possible to perform simulations that demonstrate the behavior of biogas generation related to the external conditions of the landfill that interfere with biological reactions within. The results show differences between the values obtained , it shows that the preparation of the models found and used in the simulations were allocated amounts for different parameters that determine this difference in the estimate . Therefore, to rule, the models have difficulty understanding this because there is no clarity in the formulation of the equations , and the definition of variables and parameters would require a detailed study to...

Utilização de parâmetros qualitativos dos resíduos aterrados como referência no processo de seleção de valores empregados em modelos matemáticos para a estimativa de geração de metano

The study of mathematical modeling assists in evaluation of the capacity of production and measurement of generation time of biogas in landfills, enabling the implantation of projects of energy generation from methane. Thus, the work aims, by simulating scenarios of potential methane generation in the landfill in Rio Claro, the use of field data from methane flow and waste grounded parameters as references for selecting values of k e L0 used to estimate methane generation model in LandGEM. As a result it was found that compared the characteristics adopted in the four scenarios recommended by the USEPA literature with those found in the landfill of Rio Claro (high amount of organic matter in the waste landed and daily practice of leachate recirculation), the scenario that apparently better represent the rate of methane generation is the scenario 01, with k = 0.7 and L0 = 96. Now, the adjustment of parameters in relation to the data field of methane flow, the value of L0 which best fits the methane generation from the landfill in Rio Claro is 150, while for k the line behavior that best represents the reality are values between 0.7 and 0.3. Regarding the parameters of the waste grounded, between the suggested values of k, 0,3 is most consistent with the intermediate level of biological degradation of the residue grounded, while L0 due to the biodegradability of the waste, a new value between 120 and 150 may be more appropriate for the study

A utilização de modelos matemáticos para a otimização de processos

This dissertation has as main theme the discuss about how the use of mathematical models for process optimization. The current scenario of strong competition to conquer the consumer market necessitates the development of improvements to better performance of the process as a whole, is to reduce costs, increase efficiency or effectiveness. Thus, the use of methodologies to assist in this process is becoming increasingly viable. Methodologies developed in the past are being studied and improved. An example is the Desirability, the object of the present study, which was developed in the 80's and has been improved over time. To understand and study this methodology was applied to the desirability function in three instances, where it was used Design of Experiments (DOE), taken from scientific papers, using the Solver tool (Excel ®) and desirability (Minitab ®). Thus, in addition to studying the methodology, it was possible to compare the performance of tools used for optimization in different situations. From the results of this study, it was possible to validate the superiority of one of the models studied compared fairly

Modelos matemáticos e computacionais em dengue

This work was developed starting the study of traditionals mathematical models that describe the epidemiology of infectious díseases by direct or indirect transmission. We did the classical approach of equilibrium solutions search, its analysis of stability analytically and by numerical solutions. After, we applied these techniques in a compartimental model of Dengue transmission that consider the mosquito population (susceptible vector Vs and 'infected vector VI), human population (suseeptíble humans S, infected humans I and recovered humans R) and just one sorotype floating in this population. We found the equilibrium solutions and from their analises, it was possible find the reprodution rate of dísease and which define if the disease will be endemic or not in the population.- ext, we used the method described a..~, [1] to study the infíuence of seasonalíty at vírus transmission, when it just acts on one of rates related with the vector. Lastly, we made de modeling considering the periodicity of alI rates, thereby building, a modeI with temporal dependence that permits to study periodicity of transmission through of the approach of parametrical ressonance and genetic algorithm

Modelos Matemáticos e Computacionais no Manejo Integrado de Pragas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Modelos Matemáticos e Métodos de Solução para Problemas de Dimensionamento de Lotes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Modelos matemáticos e computacionais para descrever a transmissão de dois sorotipos de vírus de dengue

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Modelagem Matemática e Análise de Modelos Matemáticos na Educação Matemática

In this paper we present two studies, the first one completed and the second one in development, which are based in teaching approaches that propose the qualitative study of mathematical models as a strategy for the teaching and learning of mathematical concepts. These teaching approaches focus on subjects from Higher Education such as Introduction to Ordinary Differential Equations and Topics of Differential and Integral Calculus. We denominate this common aspect of the teaching approaches as Model Analysis and in a preliminary level we relate it with Mathematical Modeling. Furthermore, we discuss some questions related with the choice of the theme and the role of Digital Technologies when Model Analysis is applied.

Modelos matemáticos para o problema integrado de dimensionamento de lotes e corte de estoque unidimensional

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Modelos matemáticos del crecimiento, alimentación y respiración de la trucha arco iris, salmón, tenca, anguila, rodaballo, lenguado, lubina, dorada y seriola. Aplicación al diseño de instalaciones de cultivo

En esta tesis, en su primera parte, se desarrollan modelos matemáticos para tratar de predecir el crecimiento en condiciones normales de cultivo de las siguientes especies: Trucha arco iris (Salmo garidneri), salmón (Salmón salar), tenca (Tinca tinca), anguila (Anguilla anguilla), rodaballo (Scophthalmus maximus), lenguado (Solea solea), lubina (Dicentrarchus labrax), dorada (Sparus aurata) y seriola japonesa (Seriola quinqueradiata). En la segunda parte, en base a postulados fisiológicos, se desarrollan modelos bioenergéticos que tratan de cuantificar la alimentación, crecimiento, respiración, excreción de productos nitrogenados y pérdidas fecales, en función de la tasa de alimentación, para las especies indicadas anteriormente. En la tercera parte se indican posibles utilizaciones de estos modelos para el cálculo del planning de producción, necesidades de agua y necesidades de estanques, para el caso de un cultivo intensivo de estas especies. ABSTRACT In this Doctorate Thesis, the first part is dedicated to the development of mathematical models, in order to estimate the growth, under normal culture conditions, of the following species: Rainbow trout (Salmo gairdneri)/ salmon (Salmo salara, tench (Tinca tinca), eel (Anguilla anguilla), turbot (Scophthalmus maximus), sole (Solea solea), seabass (Dicentrarchus labrax), seabream (Sparus aurata), and yellowtail (Seriola guingueradiata). In the second part, in basis to physiological postulates, bioenergetic models are developed. These models try to quantify the feeding, growth, excretion of nitrogenous and fecal products, according to the feeding rate, for the above mentioned species. In the third part, possible aplications of these models are indicated, including the production planning as well as water pond requirements for an intensive culture of the mentioned species.