36 research outputs found
Comparison Of The Optimisation Performance Of Particle Swarm Optimisation And Genetic Algorithms Applied To A Three-phase Slurry Catalytic Reactor
No full textMultiphase reactors are largely used in industrial processes like hydrogenation and oxidation with usually high throughput production. These types of industrial chemical processes are characterized by a complex dynamic behaviour that requires high dimensionality and non-linear mathematical models, being difficult to be optimised by conventional methods. In face of this, the present work aims to employ heuristic methods to optimise a type of multiphase reactor. The idea is to employ a Particle Swarm Optimisation (PSO) and to compare the performance of this method with the performance of Genetic Algorithms (GAs), when applied to a three-phase catalytic slurry reactor in which the reaction of the hydrogenation of o-cresol producing 2-methyl-cyclohexanol occurs. Heuristic optimisation methods have the advantages of not requiring manipulation of the mathematical structure of the objective function and/or constraint and not requiring an initial feasible point. PSO and GAs have been successfully applied to a range of problems and show characteristics of easiness of implementation and capability of escaping local optimal solution. In this way, in order to optimise the process, the PSO code has been coupled with the rigorous mathematical model of the reactor and the same has been done with GA code. The aim of the optimisation is the searching of the process inputs that maximize the productivity of 2-methyl-cyclohexanol subject to the environmental constraint of conversion. The comparison of the optimisation performance of both methods, PSO and GAs, can be done in relation to computational time, to objective function value and to facility of implementation, determining the suitable method for real-time optimisation. Copyright © 2009, AIDIC Servizi S.r.l.1713651370Carroll, D., (2008) Carroll's FORTRAN Genetic Algorithm Driver. In http, , cuaerospace.com/carroll/ga.html, accessed in November 16th, 2008Deb, K., An efficient constraint handling method for genetic algorithms (2000) Computer Methods in Applied Mechanics Engineering, 186, pp. 311-338Panda, S., Padhy, N.P., Comparison of particle swarm optimisation and genetic algorithm for FACTS-based controller design (2008) Applied Soft Computing, 8, pp. 1418-1427Rezende, M.C.A.F., Costa, C.B.B., Costa, A.C., Wolf Maciel, M.R., Maciel Filho, R., Optimisation of a Large Scale Industrial Reactor by Genetic Algorithms (2008) Chemical Engineering Science, 63, pp. 330-341Vasco de Toledo, E.C., Santana, P.L., Wolf Maciel, M.R., Maciel Filho, R., Dynamic Modelling of a three-phase catalytic slurry reactor (2001) Chem. Eng. Sc, 2001 (56), pp. 6055-6061Zhang, J., Xie, L., Wang, S., Particle swarm for the dynamic optimisation of biochemical processes (2006) 16th European Symposium on Computer Aided Process Engineerin
Heat exchanger networks using hybrid meta-heuristic approach
No full textPapers presented to the 12th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Costa de Sol, Spain on 11-13 July 2016.Meta-heuristic approaches have been used to achieve good
solutions in the heat exchanger network (HEN) synthesis task.
Several meta-heuristic approaches have been proposed in the
literature. Two of the most important techniques are Simulated
Annealing (SA) and Particle Swarm Optimization (PSO). In
general, SA is able to provide good solutions, but with large
computational efforts. PSO is faster than SA in finding good
solutions, but it is not capable of handling discrete variables
properly. In the present work, a bi-level HEN synthesis
approach is presented. SA is used to a single heat exchanger
addition, along with group optimizations to improve PSO
performance. A parallel processing technique is also presented
in order to improve local searching performance. The method
was tested in 3 literature case studies and results were
compared to literature solutions. The solutions presented have
lower Total Annual Costs (TAC) when compared to other
HEN. The proposed method is able to present near-optimal
solutions by more efficiently exploring the search space and
using simple moves for local searches
Arthur Mervyn; or, Memoirs of the year 1793... /
No full textThe author was a Quaker.A novel describing Philadelphia during the yellow fever epidemic in 1793.Preface signed C.B.B. [i.e. Charles Brockden Brown]Evans (1799, 1800): 35243, 37053.Mode of access: Internet
The Use Of The Modified Spline Method To Optimize Photochemical Reactors
No full text[No abstract available]Legrini, O., Oliveros, E., Braun, A.M., Chem. Rev. Data (1993), pp. 671-698. , 93(1981) Chemical Engineering Kinetics, , Smith, J. M, Eds, Mc. Graw Hill: New YorkLevenspiel, O., Eds. Engenharia das Reações QuímicasEd. Edgard Blucher ltda: São Paulo, 2000Nunhez, J.R., Mori, M., Davila, S.G., Computers chem (1993) Engng. Data, 17, pp. 1091-1099Nunhez, J.R., Costa, C.B.B., Guirardello, R., Fluid Phase Equilibria (2004) Data, 220, pp. 171-18
Cooling Crystallization: A Process-product Perspective
No full textThis paper presents a CAPE tool that focus on a wide perspective to the process and product design in a batch cooling crystallization operation. The tool comprises modules for process evaluation, design of optimal operation policy, in a process-product perspective, and the adjustment of modeling (parameter estimation). Some issues concerned to each module are discussed, like the available methods for modeling solution and the optimization, as well as the challenges in the particulate product design field. © 2006 Elsevier B.V. All rights reserved.21C967972David, R., Paulaime, A.-M., Espitalier, F., Rouleau, L., Modeling of Multiple-mechanism Agglomeration in a Crystallization Process (2003) Powder Technology, 130, pp. 338-344Gani, R., Chemical product design: challenges and opportunities (2004) Computers and Chemical Engineering, 28, pp. 2441-2457Marchal, P., David, R., Klein, J.P., Villermaux, J., Crystallization and Precipitation Enginering-I. An Efficient Method for Solving Population Balance in Crystallization with Agglomeration (1988) Chemical Engineering Science, 43, pp. 59-67Ng, K.M., A Multiscale-Multifaceted Approach to Process Synthesis and Development (2001) Proceedings of the 11 th European Symposium on Computer Aided Process Engineering, pp. 41-54. , Elsevier, Kolding, DenmarkShi, D., El-Farra, N.H., Li, M., Mhaskar, P.D.C., Predictive control of particle size distribution in particulate processes (2006) Chemical Engineering Science, 61, pp. 268-28
Arthur Mervyn; or, Memoirs of the year 1793. By the author of Wieland; and Ormond, or The secret witness. ; Copy-right secured.
No full textvi [i.e., iv], 224 p. ; 19 cm. (12mo)Preface signed: C.B.B. [i.e., Charles Brockden Brown].The second part was published at New York in 1800.Error in paging: p. iv misnumbered vi
Edgar Huntly; or, Memoirs of a sleep-walker. By the author of Arthur Mervyn, Wieland,--Ormond, &c. ; Vol I[-III].
No full text3 v. ; 19 cm. (12mo)"To the public," an authorial preface, signed: C.B.B. [i.e., Charles Brockden Brown].Title pages of v. 1 and 2 printed from the same setting of type. Title page to v. 3 printed from different setting of type. Cf. BAL.Vol. 1: 4, [1], 4-250 p.; v. 2: 252 p.; v. 3: [2], 193, [1] p.Errors in paging: v. 1, p. 2 misnumbered 4; v. 3, p. 96 misnumbered 69
Arthur Mervyn; or, Memoirs of the year 1793: By the author of Wieland; and Ormond, or The secret witness. Copy-right secured.
No full textvi [i.e., iv], 224 p. ; 12⁰.Preface signed: C.B.B. [i.e., Charles Brockden Brown].The second part was published at New York in 1800.Error in paging: p. iv misnumbered vi.Reproduction of original from the British Library.Evans, 35243BAL, 1498English Short Title Catalog, ESTCW4441.Electronic data. Farmington Hills, Mich. : Thomson Gale, 2003. Page image (PNG). Digitized image of the microfilm version produced in Woodbridge, CT by Research Publications, 1982-2002 (later known as Primary Source Microfilm, an imprint of the Gale Group)
Comparing a Dynamic Fed-Batch and a Continuous Steady-State Simulation of Ethanol Fermentation in a Distillery to a Stoichiometric Conversion Simulation
No full textEvolutionary Optimization For Soft Tissue Engineering
No full textThe development of mechanical and biological models to simulate the behaviour scaffolds for tissue engineering represents an emergent and relevant area. This paper presents an optimisation scheme using Genetic Algorithms to support the design of alginate scaffolds. The optimisation procedure maximises the elastic behaviour of alginate structures as a function of alginate composition and porosity. A shrinkage model is used to simulate the gradually loss of mechanical characteristics and dimensional changes. © 2008 Taylor & Francis Group.8185Bártolo, P.J., Almeida, H., Rezende, R.A., Laoui, T., Bidanda, B., Advanced Processes to Fabricate Scaffolds for Tissue Engineering (2007) Virtual Prototyping & Bio-Manufacturing in Medical Applications, , Edited by B. Bidanda and P.J. Bártolo, Springer, ISBN: 0387334297, in pressLanger, R., Tissue engineering: A new field and its challenges (1997) Pharmaceutical Research, 14, pp. 840-841Gomes, M.E., Reis, R.L., Biodegradable polymers and composites in biomedical applications: From catgut to tissue engineering. Part 2 Systems for temporary replacement and advanced tissue regeneration (2004) International Materials Reviews, 49, pp. 274-285Leong, K.F., Cheah, C.M., Chua, C.K., Solid freeform fabrication of the three-dimensional scaffolds for engineering replacement tissues and organs (2003) iomaterials, pp. 2363-2378. , 24Rezende, M.C.A.F., Costa, C.B.B., Costa, A.C., Wolf Maciel, M.R., Maciel Filho, R., Optimization of a Large Scale Industrial Reactor by Genetic Algorithms, Submitted a Chemical Engineering Science (2007) Under ReviewRezende, R.A., Bártolo, P.J., Mendes, A., Maciel Filho, R., Experimental characterisation of the alginate gelification process for rapid prototyping (2007) Chemical Engineering TransactionsDEB, K., An efficient constraint handling method for genetic algorithms (2000) Computer Methods in Applied Mechanics Engineering, 186, pp. 311-338CARROLL, D.L., (2007) Carroll's FORTRAN Genetic Algorithm Driver, , http://cuaerospace.com/carroll/ga.html, last access in April, 4t
