Documents disponibles écrits par cet auteur

Fisher information on the performance of dynamic systems / Rico-Ramirez, Vicente in Industrial & engineering chemistry research, Vol. 49 N° 4 (Fevrier 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 4 (Fevrier 2010) . - pp 1812–1821 Titre : Fisher information on the performance of dynamic systems Type de document : texte imprimé Auteurs : Rico-Ramirez, Vicente, Auteur ; Reyes-Mendoza, Miguel A., Auteur ; Quintana-Hernandez, Pedro A., Auteur Année de publication : 2010 Article en page(s) : pp 1812–1821 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Fisher  information  Dynamic  systems. Résumé : Recent attempts to develop sustainability theory propose the use of Fisher information as a sustainability index. The approach has been shown to be suitable for the analysis of ecological models, including dynamic simulations as well as optimal control problems where the objective function involves maximizing or minimizing Fisher information. Nevertheless, Fisher information can also be interpreted as a measure of the degree of variability of a dynamic system. The goal of this work is two-fold. First, we study the scope of using the concept of Fisher information as a sustainability index in dynamic systems different in nature from ecological systems. Then we study the behavior of Fisher information in terms of the variability and performance of the dynamic system rather than using it as a sustainability index. The results of three case studies are presented, including two chemical engineering applications (a continuous crystallization system and a series of three continuous stirred tank reactors) and a dynamic model of immunotherapy (therapeutic optimization). We perform parametric analyses, evaluating the behavior of the value of Fisher information against significant model parameters. In general, although its usefulness as a sustainability index might be difficult to interpret and elucidate in some cases, Fisher information not only can indeed be related to the degree of variability of any dynamic system, but also provides useful insights with potential application in process control. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901220w [article] Fisher information on the performance of dynamic systems [texte imprimé] / Rico-Ramirez, Vicente, Auteur ; Reyes-Mendoza, Miguel A., Auteur ; Quintana-Hernandez, Pedro A., Auteur . - 2010 . - pp 1812–1821. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 4 (Fevrier 2010) . - pp 1812–1821 Mots-clés : Fisher  information  Dynamic  systems. Résumé : Recent attempts to develop sustainability theory propose the use of Fisher information as a sustainability index. The approach has been shown to be suitable for the analysis of ecological models, including dynamic simulations as well as optimal control problems where the objective function involves maximizing or minimizing Fisher information. Nevertheless, Fisher information can also be interpreted as a measure of the degree of variability of a dynamic system. The goal of this work is two-fold. First, we study the scope of using the concept of Fisher information as a sustainability index in dynamic systems different in nature from ecological systems. Then we study the behavior of Fisher information in terms of the variability and performance of the dynamic system rather than using it as a sustainability index. The results of three case studies are presented, including two chemical engineering applications (a continuous crystallization system and a series of three continuous stirred tank reactors) and a dynamic model of immunotherapy (therapeutic optimization). We perform parametric analyses, evaluating the behavior of the value of Fisher information against significant model parameters. In general, although its usefulness as a sustainability index might be difficult to interpret and elucidate in some cases, Fisher information not only can indeed be related to the degree of variability of any dynamic system, but also provides useful insights with potential application in process control. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901220w

Simplified methodology for the design and optimization of thermally coupled reactive distillation systems / Fernando Israel Gómez-Castro in Industrial & engineering chemistry research, Vol. 51 N° 36 (Septembre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 36 (Septembre 2012) . - pp. 11717-11730 Titre : Simplified methodology for the design and optimization of thermally coupled reactive distillation systems Type de document : texte imprimé Auteurs : Fernando Israel Gómez-Castro, Auteur ; Rico-Ramirez, Vicente, Auteur ; Juan Gabriel Segovia-Hernandez, Auteur Année de publication : 2012 Article en page(s) : pp. 11717-11730 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Distillation  with  reaction  Optimization  Design Résumé : New intensified schemes have been recently proposed as an attempt to reduce energy requirements and equipment costs in reaction-separation processes. A design methodology for thermally coupled reactive distillation systems is proposed in this work. To design the columns, a method based on the Fenske―Underwood―Gilliland (FUG) equations is proposed and tested. The FUG equations, the mass and energy balances, and the phase equilibrium equations are used to formulate the model of the intensified systems. Such a model is then solved as a nonlinear programming problem; the objective function is the minimization of the heat duty in the column. Biodiesel production through the esterification of oleic acid with supercritical methanol is used as a case study. Results show the feasibility of obtaining designs with low energy requirements by using the proposed methodology. Because of nonconvexities present in the formulation, the estimated interlinking flows for the reactive Petlyuk column might not correspond to a minimum for energy requirements. Nevertheless, the resulting designs not only show low heat duties, with a difference of less than 2% from that minimum, but also have the capacity of achieving the desired conversion and purities. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26350340 [article] Simplified methodology for the design and optimization of thermally coupled reactive distillation systems [texte imprimé] / Fernando Israel Gómez-Castro, Auteur ; Rico-Ramirez, Vicente, Auteur ; Juan Gabriel Segovia-Hernandez, Auteur . - 2012 . - pp. 11717-11730. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 36 (Septembre 2012) . - pp. 11717-11730 Mots-clés : Distillation  with  reaction  Optimization  Design Résumé : New intensified schemes have been recently proposed as an attempt to reduce energy requirements and equipment costs in reaction-separation processes. A design methodology for thermally coupled reactive distillation systems is proposed in this work. To design the columns, a method based on the Fenske―Underwood―Gilliland (FUG) equations is proposed and tested. The FUG equations, the mass and energy balances, and the phase equilibrium equations are used to formulate the model of the intensified systems. Such a model is then solved as a nonlinear programming problem; the objective function is the minimization of the heat duty in the column. Biodiesel production through the esterification of oleic acid with supercritical methanol is used as a case study. Results show the feasibility of obtaining designs with low energy requirements by using the proposed methodology. Because of nonconvexities present in the formulation, the estimated interlinking flows for the reactive Petlyuk column might not correspond to a minimum for energy requirements. Nevertheless, the resulting designs not only show low heat duties, with a difference of less than 2% from that minimum, but also have the capacity of achieving the desired conversion and purities. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26350340

Strategic capacity allocation under uncertainty by using a two-stage stochastic decomposition algorithm with incumbent solutions / Sergio Frausto-Hernandez in Industrial & engineering chemistry research, Vol. 49 N° 6 (Mars 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2812–2821 Titre : Strategic capacity allocation under uncertainty by using a two-stage stochastic decomposition algorithm with incumbent solutions Type de document : texte imprimé Auteurs : Sergio Frausto-Hernandez, Auteur ; Rico-Ramirez, Vicente, Auteur ; Ignacio E. Grossmann, Auteur Année de publication : 2010 Article en page(s) : pp. 2812–2821 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Strategic  Capacity;  under  Uncertainty;  Stochastic;  Decomposition;  Algorithm;  Incumbent Résumé : This paper addresses the optimization of strategic capacity allocation problems under uncertainty. Uncertain parameters include the availabilities and the demands of chemicals. The optimization problem is formulated as a two-stage mixed-integer stochastic program (first-stage integer) that maximizes the expected net present value of the project over the time horizon. The net present value includes the discounted investment costs, operating costs, and revenues from sales in the markets. The decisions about the selection of processes and about the plant capacities are defined as the first stage decision variables; given such first stage decisions, recourse is then provided by calculating the operating costs in the second stage. The paper presents the two-stage model and the solution framework. A stochastic decomposition algorithm (SD) based on incumbent solution is used as the solution algorithm. The use of incumbent solutions as convergence criterion allows us to solve the problem in reasonable computational time. Two capacity allocation problems are used as case studies: the first one is a small size problem and is used to compare the stochastic optimal solution against other solution methods; the second one is a larger problem, with an increased number of variables and stochastic parameters. The results show that the stochastic decomposition algorithm with incumbent solutions is stable and robust and greatly reduces the number of samples required for convergence. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901021b [article] Strategic capacity allocation under uncertainty by using a two-stage stochastic decomposition algorithm with incumbent solutions [texte imprimé] / Sergio Frausto-Hernandez, Auteur ; Rico-Ramirez, Vicente, Auteur ; Ignacio E. Grossmann, Auteur . - 2010 . - pp. 2812–2821. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2812–2821 Mots-clés : Strategic  Capacity;  under  Uncertainty;  Stochastic;  Decomposition;  Algorithm;  Incumbent Résumé : This paper addresses the optimization of strategic capacity allocation problems under uncertainty. Uncertain parameters include the availabilities and the demands of chemicals. The optimization problem is formulated as a two-stage mixed-integer stochastic program (first-stage integer) that maximizes the expected net present value of the project over the time horizon. The net present value includes the discounted investment costs, operating costs, and revenues from sales in the markets. The decisions about the selection of processes and about the plant capacities are defined as the first stage decision variables; given such first stage decisions, recourse is then provided by calculating the operating costs in the second stage. The paper presents the two-stage model and the solution framework. A stochastic decomposition algorithm (SD) based on incumbent solution is used as the solution algorithm. The use of incumbent solutions as convergence criterion allows us to solve the problem in reasonable computational time. Two capacity allocation problems are used as case studies: the first one is a small size problem and is used to compare the stochastic optimal solution against other solution methods; the second one is a larger problem, with an increased number of variables and stochastic parameters. The results show that the stochastic decomposition algorithm with incumbent solutions is stable and robust and greatly reduces the number of samples required for convergence. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901021b