Publicaciones
2006 |
M.L. Caliusco, M.R. Galli, O.J. Chiotti Technologies for data semantic modelling (Artículo de revista) International Journal of Metadata, Semantics and Ontologies, 1 (4), pp. 322-331, 2006, (cited By 3). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Caliusco2006322, title = {Technologies for data semantic modelling}, author = { M.L. Caliusco and M.R. Galli and O.J. Chiotti}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-77953974167&partnerID=40&md5=0ccf73c07a9bac4ea2c91defdf79ab41}, doi = {10.1504/IJMSO.2006.012955}, year = {2006}, date = {2006-01-01}, journal = {International Journal of Metadata, Semantics and Ontologies}, volume = {1}, number = {4}, pages = {322-331}, abstract = {The explicit modelling of data semantics promises to drive information integration technology to a new level of flexibility and automation. However, nowadays, the inclusion of semantic data modelling into information system development is constrained by the lack of a supporting tool based on appropriate technologies. Our contribution in this paper is based on the specification of modelling languages that make the task of information semantics definition friendly for people who have no background knowledge of semantic modelling techniques, proposed by artificial intelligence techniques. In addition, we present a prototype that implements these languages. Copyright © 2006 Inderscience Enterprises Ltd.}, note = {cited By 3}, keywords = {}, pubstate = {published}, tppubtype = {article} } The explicit modelling of data semantics promises to drive information integration technology to a new level of flexibility and automation. However, nowadays, the inclusion of semantic data modelling into information system development is constrained by the lack of a supporting tool based on appropriate technologies. Our contribution in this paper is based on the specification of modelling languages that make the task of information semantics definition friendly for people who have no background knowledge of semantic modelling techniques, proposed by artificial intelligence techniques. In addition, we present a prototype that implements these languages. Copyright © 2006 Inderscience Enterprises Ltd. |
G. Brusa, M.L. Caliusco, O.J. Chiotti Building ontology in public administration: A case study (Conferencia) 226 , 2006, (cited By 0). (Resumen | Enlaces | BibTeX | Etiquetas: ) @conference{Brusa200616, title = {Building ontology in public administration: A case study}, author = { G. Brusa and M.L. Caliusco and O.J. Chiotti}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84884598794&partnerID=40&md5=f7158c5241725c88104a74565668f029}, year = {2006}, date = {2006-01-01}, journal = {CEUR Workshop Proceedings}, volume = {226}, pages = {16-30}, abstract = {The inclusion of Semantic Web technologies into some areas, particularly in the public sector, has not been as expected. That is, among others, because government processes require a large amount of information and its semantic is impossible to carry across organizations. Hence, public servers depend on technical and specifics areas to incorporate knowledge about information that crosses the organization structure government. It succeeds too when government administrations aim at web services and people needs access to semantic of services. In this public services transformation, it is necessary incorporate new tools to be used by community whom this services are addressed. Ontologies are important to share information in internal activities of government administration and to facilitate information access in e-government services. This work presents the experiences during the ontology building in a local public sector: the budgetary and financial system of Santa Fe Province (Argentine). Software engineering techniques were use in manner of minimize the impact of technical knowledge required. At last, architecture is proposed in order to show ontologies applications in government areas and their advantages.}, note = {cited By 0}, keywords = {}, pubstate = {published}, tppubtype = {conference} } The inclusion of Semantic Web technologies into some areas, particularly in the public sector, has not been as expected. That is, among others, because government processes require a large amount of information and its semantic is impossible to carry across organizations. Hence, public servers depend on technical and specifics areas to incorporate knowledge about information that crosses the organization structure government. It succeeds too when government administrations aim at web services and people needs access to semantic of services. In this public services transformation, it is necessary incorporate new tools to be used by community whom this services are addressed. Ontologies are important to share information in internal activities of government administration and to facilitate information access in e-government services. This work presents the experiences during the ontology building in a local public sector: the budgetary and financial system of Santa Fe Province (Argentine). Software engineering techniques were use in manner of minimize the impact of technical knowledge required. At last, architecture is proposed in order to show ontologies applications in government areas and their advantages. |
M. Rico, M.L. Caliusco, O.J. Chiotti, M.R. Galli Combining contexts and ontologies: A case study and a conceptual proposal (Conferencia) 210 , 2006, (cited By 0). (Resumen | Enlaces | BibTeX | Etiquetas: ) @conference{Rico2006, title = {Combining contexts and ontologies: A case study and a conceptual proposal}, author = { M. Rico and M.L. Caliusco and O.J. Chiotti and M.R. Galli}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84884623710&partnerID=40&md5=c65ebefe461295d1e0e8868b92e28a33}, year = {2006}, date = {2006-01-01}, journal = {CEUR Workshop Proceedings}, volume = {210}, abstract = {Recently, approaches that combine contexts and ontologies taking advantages of their strengths have been developed. Each of them solves different problems from different perspectives. The objective of this paper is to present problems that are not solved up to date as well as to introduce a conceptual proposal. To this aim, we base our analysis on a collaborative B2B scenario that is relevant for todays competitive and highly dynamic environment.}, note = {cited By 0}, keywords = {}, pubstate = {published}, tppubtype = {conference} } Recently, approaches that combine contexts and ontologies taking advantages of their strengths have been developed. Each of them solves different problems from different perspectives. The objective of this paper is to present problems that are not solved up to date as well as to introduce a conceptual proposal. To this aim, we base our analysis on a collaborative B2B scenario that is relevant for todays competitive and highly dynamic environment. |
P.D. Villarreal, H.E. Salomone, O.J. Chiotti Transforming collaborative business process models into web services choreography specifications (Artículo de revista) Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 4055 LNCS , pp. 50-65, 2006, (cited By 7). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Villarreal200650, title = {Transforming collaborative business process models into web services choreography specifications}, author = { P.D. Villarreal and H.E. Salomone and O.J. Chiotti}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-33746327178&partnerID=40&md5=4dae00ed6b462041037e7839892d9e86}, year = {2006}, date = {2006-01-01}, journal = {Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)}, volume = {4055 LNCS}, pages = {50-65}, abstract = {Languages for web services choreography are becoming more and more important for B2B integration. However, the development of web services-based systems is complex and time-consuming. Enterprises have to agree on collaborative business processes and then derive their respective web services choreographies in order to implement B2B collaboration. To support it, this paper presents a MDA approach for collaborative processes. We describe the components and techniques of this approach. We show how collaborative process models defined with the UP-ColBPIP language can be used as the main development artifact in order to derive choreography specifications based on WS-CDL. The transformations to be carried out are also discussed. The main advantage of this MDA approach is that it guarantees that the generated web services choreographies fulfill the collaborative processes agreed between the partners in a business level. © Springer-Verlag Berlin Heidelberg 2006.}, note = {cited By 7}, keywords = {}, pubstate = {published}, tppubtype = {article} } Languages for web services choreography are becoming more and more important for B2B integration. However, the development of web services-based systems is complex and time-consuming. Enterprises have to agree on collaborative business processes and then derive their respective web services choreographies in order to implement B2B collaboration. To support it, this paper presents a MDA approach for collaborative processes. We describe the components and techniques of this approach. We show how collaborative process models defined with the UP-ColBPIP language can be used as the main development artifact in order to derive choreography specifications based on WS-CDL. The transformations to be carried out are also discussed. The main advantage of this MDA approach is that it guarantees that the generated web services choreographies fulfill the collaborative processes agreed between the partners in a business level. © Springer-Verlag Berlin Heidelberg 2006. |
S. Gonnet, M. Vegetti, H.P. Leone, G. Henning SCOntology: A formal approach toward a unified and integrated view of the supply chain (Libro) 2006, (cited By 3). (Resumen | Enlaces | BibTeX | Etiquetas: ) @book{Gonnet2006137, title = {SCOntology: A formal approach toward a unified and integrated view of the supply chain}, author = { S. Gonnet and M. Vegetti and H.P. Leone and G. Henning}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-43049150328&partnerID=40&md5=055666b2e746d4fea0117ddfd515ef15}, doi = {10.4018/978-1-59904-048-6.ch007}, year = {2006}, date = {2006-01-01}, journal = {Adaptive Technologies and Business Integration: Social, Managerial and Organizational Dimensions}, pages = {137-158}, abstract = {This contribution points out the various challenges associated to Supply Chain Management (SCM). SCM involves coordinating and integrating material, information and money flows, both within and across several companies. The integration of these flows is perceived in quite distinct ways by different communities, raising some semantics-related problems. To assist organizations in achieving a unified view of the Supply Chain (SC), a new ontology, named SCOntology, is introduced in this chapter. SCOntology is a framework to formally describe a SC at various abstraction levels, by sharing a precise meaning of the information exchanged during communication among the many stakeholders involved in the SC. Moreover, SCOntology provides a foundation for the specification of information logistics processes and also sets the grounds for measuring and evaluating a SC by stating different metrics and performance-related concepts. © 2007, Idea Group Inc.}, note = {cited By 3}, keywords = {}, pubstate = {published}, tppubtype = {book} } This contribution points out the various challenges associated to Supply Chain Management (SCM). SCM involves coordinating and integrating material, information and money flows, both within and across several companies. The integration of these flows is perceived in quite distinct ways by different communities, raising some semantics-related problems. To assist organizations in achieving a unified view of the Supply Chain (SC), a new ontology, named SCOntology, is introduced in this chapter. SCOntology is a framework to formally describe a SC at various abstraction levels, by sharing a precise meaning of the information exchanged during communication among the many stakeholders involved in the SC. Moreover, SCOntology provides a foundation for the specification of information logistics processes and also sets the grounds for measuring and evaluating a SC by stating different metrics and performance-related concepts. © 2007, Idea Group Inc. |
D. Giménez, M. Vegetti, G. Henning, H.P. Leone PRoduct ONTOlogy. Defining product-related concepts for production planning activities (Artículo de revista) Computer Aided Chemical Engineering, 21 (C), pp. 2219-2224, 2006, (cited By 0). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Giménez20062219, title = {PRoduct ONTOlogy. Defining product-related concepts for production planning activities}, author = { D. Giménez and M. Vegetti and G. Henning and H.P. Leone}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-77956776096&partnerID=40&md5=a3252d0139b07d8759ac9ca6526e2a40}, doi = {10.1016/S1570-7946(06)80378-0}, year = {2006}, date = {2006-01-01}, journal = {Computer Aided Chemical Engineering}, volume = {21}, number = {C}, pages = {2219-2224}, abstract = {Current Internet-based technologies enable the operation of Extended Supply Chains (ESCs) and introduce new requirements on enterprise systems. There is a real need to manage product-related information in such ESCs, where product models are the fundamental information source. This work describes an extension of the product information framework specified by PRONTO (PRoduct ONTOlogy), providing the foundations for a Distributed Product Data Management (DPDM) system supported by Semantic Web technology. The property and property vlaue concepts were introduced in the ontology with the purpose of formalizing the data aggregation and disaggregation processes required by productionplanning activities. © 2006 Elsevier B.V. All rights reserved.}, note = {cited By 0}, keywords = {}, pubstate = {published}, tppubtype = {article} } Current Internet-based technologies enable the operation of Extended Supply Chains (ESCs) and introduce new requirements on enterprise systems. There is a real need to manage product-related information in such ESCs, where product models are the fundamental information source. This work describes an extension of the product information framework specified by PRONTO (PRoduct ONTOlogy), providing the foundations for a Distributed Product Data Management (DPDM) system supported by Semantic Web technology. The property and property vlaue concepts were introduced in the ontology with the purpose of formalizing the data aggregation and disaggregation processes required by productionplanning activities. © 2006 Elsevier B.V. All rights reserved. |
M.L. Roldán, S. Gonnet, H.P. Leone A model for capturing and tracing architectural designs (Artículo de revista) IFIP International Federation for Information Processing, 219 , pp. 16-31, 2006, (cited By 3). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Roldán200616, title = {A model for capturing and tracing architectural designs}, author = { M.L. Roldán and S. Gonnet and H.P. Leone}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-33845273827&partnerID=40&md5=1b3605b65a1fa6c0b5214dcb1bf91174}, doi = {10.1007/978-0-387-34831-5_2}, year = {2006}, date = {2006-01-01}, journal = {IFIP International Federation for Information Processing}, volume = {219}, pages = {16-31}, abstract = {Software architecture constitutes the primary design of a software system. Consequently, architectural design decisions involved in architecture design have a key impact on the system in such aspects as future maintenance costs, resulting quality, and timeliness. However, the applied knowledge employed and the design decisions taken by software architects are not explicitly represented in the design despite their important role; consequently, they remain in the mind of designers and are lost with time. In this work, a model for capturing and tracing the products and architectural design decisions involved in software architecture design processes is proposed. An operational perspective is considered in which design decisions can be modelled by means of design operations. The basic ontology of situation calculus is adopted to formally model the evolution of a software architecture. © 2006 International Federation for Information Processing.}, note = {cited By 3}, keywords = {}, pubstate = {published}, tppubtype = {article} } Software architecture constitutes the primary design of a software system. Consequently, architectural design decisions involved in architecture design have a key impact on the system in such aspects as future maintenance costs, resulting quality, and timeliness. However, the applied knowledge employed and the design decisions taken by software architects are not explicitly represented in the design despite their important role; consequently, they remain in the mind of designers and are lost with time. In this work, a model for capturing and tracing the products and architectural design decisions involved in software architecture design processes is proposed. An operational perspective is considered in which design decisions can be modelled by means of design operations. The basic ontology of situation calculus is adopted to formally model the evolution of a software architecture. © 2006 International Federation for Information Processing. |
M.L. Roldán, S. Gonnet, H.P. Leone An extensible model for representing and tracing architecture based design processes (Conferencia) 2006, (cited By 0). (Resumen | Enlaces | BibTeX | Etiquetas: ) @conference{Roldán2006361, title = {An extensible model for representing and tracing architecture based design processes}, author = { M.L. Roldán and S. Gonnet and H.P. Leone}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84886699483&partnerID=40&md5=bf2db938bb4d2bcf1db55b46cbaeaa40}, year = {2006}, date = {2006-01-01}, journal = {Actas IDEAS 2006 - 9th Workshop Iberoamericano de Ingenieria de Requisitos y Ambientes de Software}, pages = {361-374}, abstract = {Software Architecture Design is still considered as a challenging problem because it usually involves a complex process of exploration, evaluation, and composition of design alternatives. Increasingly, modeling languages, methods, and computer-aided tools are available to face these activities. However, they do not know how design is actually done. In fact, design knowledge exclusively rests in the mind of designers, and there is an urgent need to move it, as much as possible, to a computer-supported environment in order to capture this type of knowledge and make it reusable. This contribution addresses this objective by introducing a model for capturing how products under development are transformed along software architecture design processes. An operational perspective is considered where design decisions can be modeled by means of design operations. The situation calculus is used to formally express the existence of an object in a given state of a design process.}, note = {cited By 0}, keywords = {}, pubstate = {published}, tppubtype = {conference} } Software Architecture Design is still considered as a challenging problem because it usually involves a complex process of exploration, evaluation, and composition of design alternatives. Increasingly, modeling languages, methods, and computer-aided tools are available to face these activities. However, they do not know how design is actually done. In fact, design knowledge exclusively rests in the mind of designers, and there is an urgent need to move it, as much as possible, to a computer-supported environment in order to capture this type of knowledge and make it reusable. This contribution addresses this objective by introducing a model for capturing how products under development are transformed along software architecture design processes. An operational perspective is considered where design decisions can be modeled by means of design operations. The situation calculus is used to formally express the existence of an object in a given state of a design process. |
S.F. Mussati, P.A. Aguirre, N.J. Scenna Superstructure of alternative configurations of the multistage flash desalination process (Artículo de revista) Industrial and Engineering Chemistry Research, 45 (21), pp. 7190-7203, 2006, (cited By 6). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Mussati20067190, title = {Superstructure of alternative configurations of the multistage flash desalination process}, author = { S.F. Mussati and P.A. Aguirre and N.J. Scenna}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-33750342633&partnerID=40&md5=dfc40f90814027f70f9560e2615c3aef}, doi = {10.1021/ie051053y}, year = {2006}, date = {2006-01-01}, journal = {Industrial and Engineering Chemistry Research}, volume = {45}, number = {21}, pages = {7190-7203}, abstract = {This paper addresses the optimal synthesis and design of multistage flash (MSF) evaporator systems. A detailed nonlinear programming (NLP) model based on a superstructure developed previously by Mussati et al. [Ind. Eng. Chem. Res. 2003, 42, 4828-4829] has been appropriately reformulated to include more alternative configurations for the process. The new superstructure includes the number of stages and the stream flow patterns (distillate, feed and discharge brine, extraction points, and recycle flow patterns). Therefore, the superstructure simultaneously embeds an enormous number of alternatives, including, of course, the three commonly operating modes for the evaporator: MSF-BR, MSF-M, and MSF-OT systems and their combinations, which, to date, have not been analyzed systematically. In addition, a rigorous mathematical model by stage and component, which also includes the geometric design of each stage (length, height, and width), number of tubes in the preheaters, fluid-dynamic equations for the streams among others, is applied. An attractive configuration for the MSF system resulted from the proposed superstructure. This structure differs from the conventional structure, because it considers distillate extractions, two recycle streams, and new allocations for the cooling seawater, blow-down brine, and recycle. The mathematical model and the solution procedure have been implemented in GAMS [Brooke et al., GAMS: A User's Guide; Scientific Press: 1992]. Two study cases are presented, to illustrate the model and solution procedure capabilities. A complete description of the novel configuration, detailed comparison between different "sub-optimal" structures, and a sensitivity analysis on the main process variables are summarized. © 2006 American Chemical Society.}, note = {cited By 6}, keywords = {}, pubstate = {published}, tppubtype = {article} } This paper addresses the optimal synthesis and design of multistage flash (MSF) evaporator systems. A detailed nonlinear programming (NLP) model based on a superstructure developed previously by Mussati et al. [Ind. Eng. Chem. Res. 2003, 42, 4828-4829] has been appropriately reformulated to include more alternative configurations for the process. The new superstructure includes the number of stages and the stream flow patterns (distillate, feed and discharge brine, extraction points, and recycle flow patterns). Therefore, the superstructure simultaneously embeds an enormous number of alternatives, including, of course, the three commonly operating modes for the evaporator: MSF-BR, MSF-M, and MSF-OT systems and their combinations, which, to date, have not been analyzed systematically. In addition, a rigorous mathematical model by stage and component, which also includes the geometric design of each stage (length, height, and width), number of tubes in the preheaters, fluid-dynamic equations for the streams among others, is applied. An attractive configuration for the MSF system resulted from the proposed superstructure. This structure differs from the conventional structure, because it considers distillate extractions, two recycle streams, and new allocations for the cooling seawater, blow-down brine, and recycle. The mathematical model and the solution procedure have been implemented in GAMS [Brooke et al., GAMS: A User's Guide; Scientific Press: 1992]. Two study cases are presented, to illustrate the model and solution procedure capabilities. A complete description of the novel configuration, detailed comparison between different "sub-optimal" structures, and a sensitivity analysis on the main process variables are summarized. © 2006 American Chemical Society. |
G. Corsano, O.A. Iribarren, J.M. Montagna, P.A. Aguirre, E.G. Suarez Economic tradeoffs involved in the design of fermentation processes with environmental constraints (Artículo de revista) Chemical Engineering Research and Design, 84 (10 A), pp. 932-942, 2006, (cited By 7). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Corsano2006932, title = {Economic tradeoffs involved in the design of fermentation processes with environmental constraints}, author = { G. Corsano and O.A. Iribarren and J.M. Montagna and P.A. Aguirre and E.G. Suarez}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-33750526419&partnerID=40&md5=dfa4c8b92924fde35991c3dacb666e07}, doi = {10.1205/cherd06016}, year = {2006}, date = {2006-01-01}, journal = {Chemical Engineering Research and Design}, volume = {84}, number = {10 A}, pages = {932-942}, abstract = {A process model is used for analysing the economic tradeoffs involved in the synthesis, design and operation of a typical batch fermentation plant involving batch and semi-continuous operations with the recycle of the otherwise waste stream that results after the recovery of the product of interest from the fermentation broth. This recycle contributes to a more complete substrate consumption, water reuse and reduction of the environmental impact of the process. Process variables are optimized simultaneously with the plant structure by formulating the whole optimization problem as a non linear programme (NLP). The environmental concern about producing large amounts of fermentation broth waste was accounted for by penalizing its production combined with allowing their recycle to the different types of fermenters based on process considerations. Optimal design and operation are pursued, analysing the economic tradeoffs involved in selecting the number and operation mode of biomass grow and metabolite fermenters, sugar substrate blending to each fermenter, recycle of fermentation broth waste, initial and final concentrations of biomass, substrate and metabolite, and the role of idle times in the process. The paper reports some optimal plant structures and figures for process variables not implemented in industrial practices but supported by process analysis arguments, thus suggesting that they may be worth exploring. © 2006 Institution of Chemical Engineers.}, note = {cited By 7}, keywords = {}, pubstate = {published}, tppubtype = {article} } A process model is used for analysing the economic tradeoffs involved in the synthesis, design and operation of a typical batch fermentation plant involving batch and semi-continuous operations with the recycle of the otherwise waste stream that results after the recovery of the product of interest from the fermentation broth. This recycle contributes to a more complete substrate consumption, water reuse and reduction of the environmental impact of the process. Process variables are optimized simultaneously with the plant structure by formulating the whole optimization problem as a non linear programme (NLP). The environmental concern about producing large amounts of fermentation broth waste was accounted for by penalizing its production combined with allowing their recycle to the different types of fermenters based on process considerations. Optimal design and operation are pursued, analysing the economic tradeoffs involved in selecting the number and operation mode of biomass grow and metabolite fermenters, sugar substrate blending to each fermenter, recycle of fermentation broth waste, initial and final concentrations of biomass, substrate and metabolite, and the role of idle times in the process. The paper reports some optimal plant structures and figures for process variables not implemented in industrial practices but supported by process analysis arguments, thus suggesting that they may be worth exploring. © 2006 Institution of Chemical Engineers. |
S.F. Mussati, P.A. Aguirre, N.J. Scenna Thermodynamic approach for optimal design of heat and power plants. Relationships between thermodynamic and economic solutions (Artículo de revista) Latin American Applied Research, 36 (4), pp. 329-335, 2006, (cited By 4). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Mussati2006329, title = {Thermodynamic approach for optimal design of heat and power plants. Relationships between thermodynamic and economic solutions}, author = { S.F. Mussati and P.A. Aguirre and N.J. Scenna}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-33845548559&partnerID=40&md5=1eb83457c7a2c4e5d7c5c5ce4596dfd6}, year = {2006}, date = {2006-01-01}, journal = {Latin American Applied Research}, volume = {36}, number = {4}, pages = {329-335}, abstract = {In this paper, a new procedure for the design and analysis of Heat and Power Plants is presented. In this formulation, thermodynamic solutions obtained by maximizing the plant efficiency are used to find the economic design of the plant. In fact, by applying the Karush-Kuhn-Tucker conditions it is possible to relate thermodynamic and economic solutions. A formal context for the use of thermodynamic models in solving complex optimization problems that arise in the area of synthesis and design of chemical processes is introduced. The proposed methodology has been successfully applied for two plant arrangements. Rigorous models have been used to model the plant equipments. The obtained results are presented in order to illustrate the proposed procedure.}, note = {cited By 4}, keywords = {}, pubstate = {published}, tppubtype = {article} } In this paper, a new procedure for the design and analysis of Heat and Power Plants is presented. In this formulation, thermodynamic solutions obtained by maximizing the plant efficiency are used to find the economic design of the plant. In fact, by applying the Karush-Kuhn-Tucker conditions it is possible to relate thermodynamic and economic solutions. A formal context for the use of thermodynamic models in solving complex optimization problems that arise in the area of synthesis and design of chemical processes is introduced. The proposed methodology has been successfully applied for two plant arrangements. Rigorous models have been used to model the plant equipments. The obtained results are presented in order to illustrate the proposed procedure. |
G. Corsano, J.M. Montagna, O.A. Iribarren, P.A. Aguirre Design and operation issues using NLP superstructure modeling (Artículo de revista) Applied Mathematical Modelling, 30 (9), pp. 974-992, 2006, (cited By 3). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Corsano2006974, title = {Design and operation issues using NLP superstructure modeling}, author = { G. Corsano and J.M. Montagna and O.A. Iribarren and P.A. Aguirre}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-33745150765&partnerID=40&md5=b33a361eeb22f3422cff2fe0f5ea4491}, doi = {10.1016/j.apm.2005.07.003}, year = {2006}, date = {2006-01-01}, journal = {Applied Mathematical Modelling}, volume = {30}, number = {9}, pages = {974-992}, abstract = {Till present, models that determined batch plants configurations in the chemical process industry resorted to models with binary variables to represent the different admissible options. This approach allowed representing the problem in a simple way while considering a significant number of alternatives. Nevertheless, the non-convexity that arises when dealing with detailed models for representing the involved units operation prevents its correct resolution or has a low performance. This work presents a representation of the problem through a superstructure that takes explicitly into account all the alternatives without resorting to binary variables. By using extremely simple modeling, it is possible to manage an appropriate number of options for this type of problems by means of a non-linear programming (NLP) model. Moreover, it is possible to consider duplication in series of production stages, which is an alternative that has not been used till now. This approach is posed for the case of a fermentors network. The solution is reached with very low requirements as regards employed computer time and without the aforementioned difficulties. © 2005 Elsevier Inc. All rights reserved.}, note = {cited By 3}, keywords = {}, pubstate = {published}, tppubtype = {article} } Till present, models that determined batch plants configurations in the chemical process industry resorted to models with binary variables to represent the different admissible options. This approach allowed representing the problem in a simple way while considering a significant number of alternatives. Nevertheless, the non-convexity that arises when dealing with detailed models for representing the involved units operation prevents its correct resolution or has a low performance. This work presents a representation of the problem through a superstructure that takes explicitly into account all the alternatives without resorting to binary variables. By using extremely simple modeling, it is possible to manage an appropriate number of options for this type of problems by means of a non-linear programming (NLP) model. Moreover, it is possible to consider duplication in series of production stages, which is an alternative that has not been used till now. This approach is posed for the case of a fermentors network. The solution is reached with very low requirements as regards employed computer time and without the aforementioned difficulties. © 2005 Elsevier Inc. All rights reserved. |
M.C. Mussati, P.A. Aguirre, M. Fuentes, N. Scenna Aspects on methanogenic biofilm reactor modeling (Artículo de revista) Latin American Applied Research, 36 (3), pp. 173-180, 2006, (cited By 4). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Mussati2006173, title = {Aspects on methanogenic biofilm reactor modeling}, author = { M.C. Mussati and P.A. Aguirre and M. Fuentes and N. Scenna}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-33748572612&partnerID=40&md5=e7268a8de6c60576a00546989c129078}, year = {2006}, date = {2006-01-01}, journal = {Latin American Applied Research}, volume = {36}, number = {3}, pages = {173-180}, abstract = {A previously developed deterministic steady state module for modeling methanogenic biofilm reactors has been revised to enlarge the model application range and to deal with system dynamics. Two models for the hydrolysis of non-active biomass representing extreme alternatives: without biomass hydrolysis (model A) and with complete and instantaneous hydrolysis of non-active suspended and attached biomass (model B) were investigated. Both models resulted to be suitable for simulating highly anaerobic loaded systems. However, only model B showed good agreement between experimental and calculated values at low organic loading rates. The values of the specific biofilm detachment rate and the specific microbial death rate of the original model were re-estimated for model B based on a set of step-type disturbances on the organic loading rates. At loading rates ranging between 2 to 4 g COD per day per liter of expanded bed applied to a lab-scale fluidized bed reactor, the parameter estimates were 0.0269 Lg-1d-1 and 0.061 d -1 for the specific biofilm detachment rate and the specific death rate, respectively, with a 95% chi-square confidence level.}, note = {cited By 4}, keywords = {}, pubstate = {published}, tppubtype = {article} } A previously developed deterministic steady state module for modeling methanogenic biofilm reactors has been revised to enlarge the model application range and to deal with system dynamics. Two models for the hydrolysis of non-active biomass representing extreme alternatives: without biomass hydrolysis (model A) and with complete and instantaneous hydrolysis of non-active suspended and attached biomass (model B) were investigated. Both models resulted to be suitable for simulating highly anaerobic loaded systems. However, only model B showed good agreement between experimental and calculated values at low organic loading rates. The values of the specific biofilm detachment rate and the specific microbial death rate of the original model were re-estimated for model B based on a set of step-type disturbances on the organic loading rates. At loading rates ranging between 2 to 4 g COD per day per liter of expanded bed applied to a lab-scale fluidized bed reactor, the parameter estimates were 0.0269 Lg-1d-1 and 0.061 d -1 for the specific biofilm detachment rate and the specific death rate, respectively, with a 95% chi-square confidence level. |
G. Corsano, J.M. Montagna, O.A. Iribarren, P.A. Aguirre Processes integration: Multiplant complex vs multipurpose plant assessment (Artículo de revista) Industrial and Engineering Chemistry Research, 45 (12), pp. 4256-4269, 2006, (cited By 2). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Corsano20064256, title = {Processes integration: Multiplant complex vs multipurpose plant assessment}, author = { G. Corsano and J.M. Montagna and O.A. Iribarren and P.A. Aguirre}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-33745670883&partnerID=40&md5=526d2d3509967c70ddb930aeed3e2256}, doi = {10.1021/ie051454d}, year = {2006}, date = {2006-01-01}, journal = {Industrial and Engineering Chemistry Research}, volume = {45}, number = {12}, pages = {4256-4269}, abstract = {This paper presents a tool for the generation and evaluation of different alternatives of product production. The importance of this approach lies in the integration of synthesis, design, operation, and scheduling decisions. When simultaneously approached, these decisions allow consideration of the relationships and effects between critical elements of the problem that are usually analyzed sequentially. Two different scenarios are modeled in order to evaluate and select which production process is convenient to develop: multipurpose plant and multiplant complex with single-product batch plants. The methodology is illustrated by an industrially motivated case study involving the production of three products: torula yeast, bakery yeast, and brandy. According to different production conditions, both scenarios are solved, and the analysis and conclusions with regards to the most favorable production scheme are reported. © 2006 American Chemical Society.}, note = {cited By 2}, keywords = {}, pubstate = {published}, tppubtype = {article} } This paper presents a tool for the generation and evaluation of different alternatives of product production. The importance of this approach lies in the integration of synthesis, design, operation, and scheduling decisions. When simultaneously approached, these decisions allow consideration of the relationships and effects between critical elements of the problem that are usually analyzed sequentially. Two different scenarios are modeled in order to evaluate and select which production process is convenient to develop: multipurpose plant and multiplant complex with single-product batch plants. The methodology is illustrated by an industrially motivated case study involving the production of three products: torula yeast, bakery yeast, and brandy. According to different production conditions, both scenarios are solved, and the analysis and conclusions with regards to the most favorable production scheme are reported. © 2006 American Chemical Society. |
M.C. Mussati, P.A. Aguirre, J. Espinosa, O.A. Iribarren Optimal design of azeotropic batch distillation (Artículo de revista) AIChE Journal, 52 (3), pp. 968-985, 2006, (cited By 6). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Mussati2006968, title = {Optimal design of azeotropic batch distillation}, author = { M.C. Mussati and P.A. Aguirre and J. Espinosa and O.A. Iribarren}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-33645637314&partnerID=40&md5=11e91f38e71ff7f25e0c9b47b1952891}, doi = {10.1002/aic.10696}, year = {2006}, date = {2006-01-01}, journal = {AIChE Journal}, volume = {52}, number = {3}, pages = {968-985}, abstract = {This study explores integrating models with different degrees of detail for optimizing azeotropic batch distillation systems. A detailed dynamic model is used from outside the optimization program both to verify feasibility of the design and to update the parameters needed by the optimization model. The updated parameters are the constant relative volatilities between pseudo-components, used in a binary Fenske-Underwood-Gillilandtype model. The approach was used to optimize the design of a batch process for the recovery of spent isopropyl alcohol, which works cyclically to separate the excess water, satisfying an environmentally acceptable specification, and using cyclohexane as entrainer, which in turn is recovered in the same process and recycled. The approach permitted optimizing the batch sizes, number of separation stages, the reflux ratios of a piecewise constant multilevel reflux policy, the extent of each separation, and the size of the intermediate cuts to be recycled, with affordable computation and problem setup times. © 2005 American Institute of Chemical Engineers.}, note = {cited By 6}, keywords = {}, pubstate = {published}, tppubtype = {article} } This study explores integrating models with different degrees of detail for optimizing azeotropic batch distillation systems. A detailed dynamic model is used from outside the optimization program both to verify feasibility of the design and to update the parameters needed by the optimization model. The updated parameters are the constant relative volatilities between pseudo-components, used in a binary Fenske-Underwood-Gillilandtype model. The approach was used to optimize the design of a batch process for the recovery of spent isopropyl alcohol, which works cyclically to separate the excess water, satisfying an environmentally acceptable specification, and using cyclohexane as entrainer, which in turn is recovered in the same process and recycled. The approach permitted optimizing the batch sizes, number of separation stages, the reflux ratios of a piecewise constant multilevel reflux policy, the extent of each separation, and the size of the intermediate cuts to be recycled, with affordable computation and problem setup times. © 2005 American Institute of Chemical Engineers. |
M.G. Marcovecchio, M.L. Bergamini, P.A. Aguirre Improve-and-branch algorithm for the global optimization of nonconvex NLP problems (Artículo de revista) Journal of Global Optimization, 34 (3), pp. 339-368, 2006, (cited By 3). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Marcovecchio2006339, title = {Improve-and-branch algorithm for the global optimization of nonconvex NLP problems}, author = { M.G. Marcovecchio and M.L. Bergamini and P.A. Aguirre}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-33644795198&partnerID=40&md5=afdf80061de92d98c091cc2edf2c4490}, doi = {10.1007/s10898-005-4386-3}, year = {2006}, date = {2006-01-01}, journal = {Journal of Global Optimization}, volume = {34}, number = {3}, pages = {339-368}, abstract = {A new algorithm to solve nonconvex NLP problems is presented. It is based on the solution of two problems. The reformulated problem RP is a suitable reformulation of the original problem and involves convex terms and concave univariate terms. The main problem MP is a nonconvex NLP that outer-approximates the feasible region and underestimate the objective function. MP involves convex terms and terms which are the products of concave univariate functions and new variables. Fixing the variables in the concave terms, a convex NLP that overestimates the feasible region and underestimates the objective function is obtained from the MP. Like most of the deterministic global optimization algorithms, bounds on all the variables in the nonconvex terms must be provided. MP forces the objective value to improve and minimizes the difference of upper and lower bound of all the variables either to zero or to a positive value. In the first case, a feasible solution of the original problem is reached and the objective function is improved. In general terms, the second case corresponds to an infeasible solution of the original problem due to the existence of gaps in some variables. A branching procedure is performed in order to either prove that there is no better solution or reduce the domain, eliminating the local solution of MP that was found. The MP solution indicates a key point to do the branching. A bound reduction technique is implemented to accelerate the convergence speed. Computational results demonstrate that the algorithm compares very favorably to other approaches when applied to test problems and process design problems. It is typically faster and it produces very accurate results. © Springer 2006.}, note = {cited By 3}, keywords = {}, pubstate = {published}, tppubtype = {article} } A new algorithm to solve nonconvex NLP problems is presented. It is based on the solution of two problems. The reformulated problem RP is a suitable reformulation of the original problem and involves convex terms and concave univariate terms. The main problem MP is a nonconvex NLP that outer-approximates the feasible region and underestimate the objective function. MP involves convex terms and terms which are the products of concave univariate functions and new variables. Fixing the variables in the concave terms, a convex NLP that overestimates the feasible region and underestimates the objective function is obtained from the MP. Like most of the deterministic global optimization algorithms, bounds on all the variables in the nonconvex terms must be provided. MP forces the objective value to improve and minimizes the difference of upper and lower bound of all the variables either to zero or to a positive value. In the first case, a feasible solution of the original problem is reached and the objective function is improved. In general terms, the second case corresponds to an infeasible solution of the original problem due to the existence of gaps in some variables. A branching procedure is performed in order to either prove that there is no better solution or reduce the domain, eliminating the local solution of MP that was found. The MP solution indicates a key point to do the branching. A bound reduction technique is implemented to accelerate the convergence speed. Computational results demonstrate that the algorithm compares very favorably to other approaches when applied to test problems and process design problems. It is typically faster and it produces very accurate results. © Springer 2006. |
N. Alasinoa, M.C. Mussati, N. Scenna Optimization of the operation conditions for denitrifying wastewater treatment plants (Conferencia) 2006, (cited By 2). (Resumen | Enlaces | BibTeX | Etiquetas: ) @conference{Alasinoa2006427, title = {Optimization of the operation conditions for denitrifying wastewater treatment plants}, author = { N. Alasinoa and M.C. Mussati and N. Scenna}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-52749093179&partnerID=40&md5=6537e7e4737bc42479eaa4f0a17cf3e4}, year = {2006}, date = {2006-01-01}, journal = {International Mediterranean Modelling Multiconference, I3M}, pages = {427-434}, abstract = {Optimal operation condition for biological nitrogen removal and organic matter oxidation for selected wastewater treatment plant configurations in continuous operation was investigated. The optimization of each proposed configuration aims to minimize the total annual operation cost while predicting compliance with the effluent permitted limits. Defined influent wastewater flow and composition are assumed, and the plant equipment size is supposed given. Each configuration plant consists of five reaction compartments, tree of which are aerated and two anoxic, and a secondary settler. The Activated Sludge Model No. 3 and the Tákacs model are used to model the reaction compartments and the secondary settler, respectively, resulting in a highly nonlinear system. The three conventional plant configurations for biological nitrogen removal, i. e. predenitrification, postdenitrification and pre-postdenitrification systems are extended considering flow distribution of the nitrate and sludge recycle streams and fresh feed stream along the reaction zone. The resulting mathematical model is a Non-Linear-Programming problem. A reaction performance indicator is defined aiming to compare the different operation strategies obtained as optimal solution for each case.}, note = {cited By 2}, keywords = {}, pubstate = {published}, tppubtype = {conference} } Optimal operation condition for biological nitrogen removal and organic matter oxidation for selected wastewater treatment plant configurations in continuous operation was investigated. The optimization of each proposed configuration aims to minimize the total annual operation cost while predicting compliance with the effluent permitted limits. Defined influent wastewater flow and composition are assumed, and the plant equipment size is supposed given. Each configuration plant consists of five reaction compartments, tree of which are aerated and two anoxic, and a secondary settler. The Activated Sludge Model No. 3 and the Tákacs model are used to model the reaction compartments and the secondary settler, respectively, resulting in a highly nonlinear system. The three conventional plant configurations for biological nitrogen removal, i. e. predenitrification, postdenitrification and pre-postdenitrification systems are extended considering flow distribution of the nitrate and sludge recycle streams and fresh feed stream along the reaction zone. The resulting mathematical model is a Non-Linear-Programming problem. A reaction performance indicator is defined aiming to compare the different operation strategies obtained as optimal solution for each case. |
R.L. Martin, J.M. Montagna Business process reengineering role in electronic government (Artículo de revista) IFIP International Federation for Information Processing, 214 , pp. 77-88, 2006, (cited By 1). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Martin200677, title = {Business process reengineering role in electronic government}, author = { R.L. Martin and J.M. Montagna}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-33845274509&partnerID=40&md5=5de75ca4c6450881d9116bcac8cedb1c}, doi = {10.1007/978-0-387-34732-5_8}, year = {2006}, date = {2006-01-01}, journal = {IFIP International Federation for Information Processing}, volume = {214}, pages = {77-88}, abstract = {Business Process Reengineering (BPR) came up as a key concept in the 1990s, with a high impact on management and transactions of private companies. However, it has not been so well accepted in public administration. Nowadays, many projects for changes in government are related to electronic government. According to this, this article discusses the role of BPR in this context, its contribution to this kind of initiative, and if it is a required element to go forward. Also, the difficulties in carrying out the BPR in the particular case of e-government are analyzed, taking into account the characteristics of this kind of project, the stages that are generally involved and the environment in which it is performed. Finally, a basic structure for the development of egovernment is provided, specifying the insertion of BPR for reaching a more efficient, effective and foreseeable management of new projects. © 2006 International Federation for Information Processing.}, note = {cited By 1}, keywords = {}, pubstate = {published}, tppubtype = {article} } Business Process Reengineering (BPR) came up as a key concept in the 1990s, with a high impact on management and transactions of private companies. However, it has not been so well accepted in public administration. Nowadays, many projects for changes in government are related to electronic government. According to this, this article discusses the role of BPR in this context, its contribution to this kind of initiative, and if it is a required element to go forward. Also, the difficulties in carrying out the BPR in the particular case of e-government are analyzed, taking into account the characteristics of this kind of project, the stages that are generally involved and the environment in which it is performed. Finally, a basic structure for the development of egovernment is provided, specifying the insertion of BPR for reaching a more efficient, effective and foreseeable management of new projects. © 2006 International Federation for Information Processing. |
L.C. Ballejos, J.M. Montagna Stakeholders selection for interorganizational systems: A systematic approach (Artículo de revista) IFIP International Federation for Information Processing, 214 , pp. 39-50, 2006, (cited By 3). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Ballejos200639, title = {Stakeholders selection for interorganizational systems: A systematic approach}, author = { L.C. Ballejos and J.M. Montagna}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-33845255255&partnerID=40&md5=273a1856fbaf07cfb7073011cfd158c9}, doi = {10.1007/978-0-387-34732-5_4}, year = {2006}, date = {2006-01-01}, journal = {IFIP International Federation for Information Processing}, volume = {214}, pages = {39-50}, abstract = {Stakeholders identification is a critical task for successful software projects. In general, there are no methodologies that allow performing it in a systematic way. Besides, several facts must be analyzed when the project is carried out in a context formed by multiple organizations. The complexity of these environments makes the task extremely hard. To face these difficulties, stakeholders are defined and analyzed taking into account the characteristics of the interorganizational dimension. Also a methodology is proposed for canying out their identification that allows systematically specifying all people, groups and organizations whose interests and needs are affected by the information system in all the involved dimensions. © 2006 International Federation for Information Processing.}, note = {cited By 3}, keywords = {}, pubstate = {published}, tppubtype = {article} } Stakeholders identification is a critical task for successful software projects. In general, there are no methodologies that allow performing it in a systematic way. Besides, several facts must be analyzed when the project is carried out in a context formed by multiple organizations. The complexity of these environments makes the task extremely hard. To face these difficulties, stakeholders are defined and analyzed taking into account the characteristics of the interorganizational dimension. Also a methodology is proposed for canying out their identification that allows systematically specifying all people, groups and organizations whose interests and needs are affected by the information system in all the involved dimensions. © 2006 International Federation for Information Processing. |
2005 |
R.A. Ghraizi, E.C. Martínez, C.d. Prada, F. Cifuentes, J.L. Martínez Performance monitoring of industrial controllers based on the predictability of controller behavior (Artículo de revista) Computer Aided Chemical Engineering, 20 (C), pp. 1099-1104, 2005, (cited By 0). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Ghraizi20051099, title = {Performance monitoring of industrial controllers based on the predictability of controller behavior}, author = { R.A. Ghraizi and E.C. Martínez and C.d. Prada and F. Cifuentes and J.L. Martínez}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-77956733423&partnerID=40&md5=048653e1234bcd87145de34b546100e2}, doi = {10.1016/S1570-7946(05)80025-2}, year = {2005}, date = {2005-01-01}, journal = {Computer Aided Chemical Engineering}, volume = {20}, number = {C}, pages = {1099-1104}, abstract = {This study focuses on performance assessment of industrial controllers. A methodology based on the concept of the predictability of controller errors is proposed for performance monitoring. The proposed approach is based on evaluating controller behaviour by analysing the time series of error and to verify the existence predictable patterns beyond the control horizon in each one of the controlled variables of the process. To favour its implementation in a plant information system proper selection of some tuning parameters depending on the type of loop (temperature, level, pressure, etc.) is discussed. Examples using industrial data from a refinery are provided. © 2005 Elsevier B.V. All rights reserved.}, note = {cited By 0}, keywords = {}, pubstate = {published}, tppubtype = {article} } This study focuses on performance assessment of industrial controllers. A methodology based on the concept of the predictability of controller errors is proposed for performance monitoring. The proposed approach is based on evaluating controller behaviour by analysing the time series of error and to verify the existence predictable patterns beyond the control horizon in each one of the controlled variables of the process. To favour its implementation in a plant information system proper selection of some tuning parameters depending on the type of loop (temperature, level, pressure, etc.) is discussed. Examples using industrial data from a refinery are provided. © 2005 Elsevier B.V. All rights reserved. |
S. Syafiie, F. Tadeo, E.C. Martínez Model-free intelligent control using reinforcement learning and temporal abstraction-applied to pH control (Conferencia) 16 , 2005, (cited By 1). (Resumen | Enlaces | BibTeX | Etiquetas: ) @conference{Syafiie2005127, title = {Model-free intelligent control using reinforcement learning and temporal abstraction-applied to pH control}, author = { S. Syafiie and F. Tadeo and E.C. Martínez}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-79960704873&partnerID=40&md5=8cc60196d19ac59ce11733b004d9beb5}, year = {2005}, date = {2005-01-01}, journal = {IFAC Proceedings Volumes (IFAC-PapersOnline)}, volume = {16}, pages = {127-132}, abstract = {This article presents a solution to pH control based on model-free intelligent control (MFIC) using reinforcement learning. This control technique is proposed because the algorithm gives a general solution for acid-base system, yet simple enough for its implementation in existing control hardware. in standard reinforcement learning, the interaction between an agent and the environment is based on a fixed time scale: during learning, the agent can select several primitive actions depending on the system state. A novel solution is presented, using multistep actions (MSA): actions on multiple time scales consist of several identical primitive actions. This solves the problem of determining a suitable fixed time scale to select control actions so as to trade off accuracy in control against learning complexity. The application of multi-step actions on a simulated pH process shows that the proposed MFIC learns to control adequately the neutralization process. Copyright © 2005 IFAC.}, note = {cited By 1}, keywords = {}, pubstate = {published}, tppubtype = {conference} } This article presents a solution to pH control based on model-free intelligent control (MFIC) using reinforcement learning. This control technique is proposed because the algorithm gives a general solution for acid-base system, yet simple enough for its implementation in existing control hardware. in standard reinforcement learning, the interaction between an agent and the environment is based on a fixed time scale: during learning, the agent can select several primitive actions depending on the system state. A novel solution is presented, using multistep actions (MSA): actions on multiple time scales consist of several identical primitive actions. This solves the problem of determining a suitable fixed time scale to select control actions so as to trade off accuracy in control against learning complexity. The application of multi-step actions on a simulated pH process shows that the proposed MFIC learns to control adequately the neutralization process. Copyright © 2005 IFAC. |
E.C. Martínez Statistical simplex method for experimental design in process optimization (Artículo de revista) Industrial and Engineering Chemistry Research, 44 (23), pp. 8796-8805, 2005, (cited By 2). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Martínez20058796, title = {Statistical simplex method for experimental design in process optimization}, author = { E.C. Martínez}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-28444442973&partnerID=40&md5=c871d3233fcd7edf1f823afc0aa7dc4b}, doi = {10.1021/ie050165m}, year = {2005}, date = {2005-01-01}, journal = {Industrial and Engineering Chemistry Research}, volume = {44}, number = {23}, pages = {8796-8805}, abstract = {Experimental optimization with scarce and noisy process data is a key issue in laboratory automation for faster chemical process research and development, real-time process optimization, and the ability to embed a learning capability into the design of self-calibrating instruments and extremum-seeking controllers. To deal successfully with noise and uncontrollable factors in experimental design for process optimization, a statistical characterization of an optimum using process data is proposed. The Kendall's tau statistic is used for identifying a minimum (maximum) in a data set as a cluster center of positively (negatively) correlated points. A new simplex search algorithm with a logic that resorts to correlation-based ranking of simplex vertices for reflection, expansion, contraction, and shrinking steps is proposed. The advantage of resorting to a data set that cumulatively provides a global perspective of the output landscape through Kendall's tau calculations is a novel feature of the statistical simplex method. Encouraging results obtained for Rastringin's multimodal function and in the optimization of the operating policy for a semibatch reactor are presented. © 2005 American Chemical Society.}, note = {cited By 2}, keywords = {}, pubstate = {published}, tppubtype = {article} } Experimental optimization with scarce and noisy process data is a key issue in laboratory automation for faster chemical process research and development, real-time process optimization, and the ability to embed a learning capability into the design of self-calibrating instruments and extremum-seeking controllers. To deal successfully with noise and uncontrollable factors in experimental design for process optimization, a statistical characterization of an optimum using process data is proposed. The Kendall's tau statistic is used for identifying a minimum (maximum) in a data set as a cluster center of positively (negatively) correlated points. A new simplex search algorithm with a logic that resorts to correlation-based ranking of simplex vertices for reflection, expansion, contraction, and shrinking steps is proposed. The advantage of resorting to a data set that cumulatively provides a global perspective of the output landscape through Kendall's tau calculations is a novel feature of the statistical simplex method. Encouraging results obtained for Rastringin's multimodal function and in the optimization of the operating policy for a semibatch reactor are presented. © 2005 American Chemical Society. |
E.C. Martínez Model discrimination and selection in evolutionary optimization of batch processes with tendency models (Artículo de revista) Computer Aided Chemical Engineering, 20 (C), pp. 463-468, 2005, (cited By 1). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Martínez2005463, title = {Model discrimination and selection in evolutionary optimization of batch processes with tendency models}, author = { E.C. Martínez}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-77956743756&partnerID=40&md5=59f98f4d3bd7297bb5cfe0639d0bca18}, doi = {10.1016/S1570-7946(05)80199-3}, year = {2005}, date = {2005-01-01}, journal = {Computer Aided Chemical Engineering}, volume = {20}, number = {C}, pages = {463-468}, abstract = {Batch processes increasingly feature products with short market windows that make the development of a detailed kinetic model unattractive in terms of both time and economy. Tendency modeling is already established as a systematic methodology for timely optimization of batch processes using a gray-box model approach. In this work, the problem of effective discrimination among alternative tendency models is addressed using rank correlation methods and pair-wise bisection approach to model concordance. The Kendall tau statistics is used to measure model correlation and concordance with regards to alternative optimum predictions. Less promising tendency models are gradually eliminated using a softmax criterion which trades off exploitation with exploration for experiment planning. © 2005 Elsevier B.V. All rights reserved.}, note = {cited By 1}, keywords = {}, pubstate = {published}, tppubtype = {article} } Batch processes increasingly feature products with short market windows that make the development of a detailed kinetic model unattractive in terms of both time and economy. Tendency modeling is already established as a systematic methodology for timely optimization of batch processes using a gray-box model approach. In this work, the problem of effective discrimination among alternative tendency models is addressed using rank correlation methods and pair-wise bisection approach to model concordance. The Kendall tau statistics is used to measure model correlation and concordance with regards to alternative optimum predictions. Less promising tendency models are gradually eliminated using a softmax criterion which trades off exploitation with exploration for experiment planning. © 2005 Elsevier B.V. All rights reserved. |
E.C. Martínez The statistical simplex method for experimental optimization with process data (Artículo de revista) Computer Aided Chemical Engineering, 20 (C), pp. 31-36, 2005, (cited By 2). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Martínez200531, title = {The statistical simplex method for experimental optimization with process data}, author = { E.C. Martínez}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-77956744420&partnerID=40&md5=c9bcbbdbda0f634e01d5f522f8a2f7d5}, doi = {10.1016/S1570-7946(05)80127-0}, year = {2005}, date = {2005-01-01}, journal = {Computer Aided Chemical Engineering}, volume = {20}, number = {C}, pages = {31-36}, abstract = {Experimental optimization with scarce and noisy process data is a key issue in laboratory automation for faster chemical process research and development, real-time process optimization, extremum-seeking control systems and self-calibrating instruments. To deal successfully with noise and uncontrollable factors in experimental design for process optimization a statistical characterization of a local optimum is proposed. The Kendall's tau statistic is used for characterizing a local optimum as a cluster center of strongly correlated points. A statistical simplex algorithm that resorts to correlation-based ranking of simplex vertices for reflection, expansion, contraction and shrinking steps is proposed. Results obtained in run-to-run optimization of the operating policy of a semi-batch reactor are presented. © 2005 Elsevier B.V. All rights reserved.}, note = {cited By 2}, keywords = {}, pubstate = {published}, tppubtype = {article} } Experimental optimization with scarce and noisy process data is a key issue in laboratory automation for faster chemical process research and development, real-time process optimization, extremum-seeking control systems and self-calibrating instruments. To deal successfully with noise and uncontrollable factors in experimental design for process optimization a statistical characterization of a local optimum is proposed. The Kendall's tau statistic is used for characterizing a local optimum as a cluster center of strongly correlated points. A statistical simplex algorithm that resorts to correlation-based ranking of simplex vertices for reflection, expansion, contraction and shrinking steps is proposed. Results obtained in run-to-run optimization of the operating policy of a semi-batch reactor are presented. © 2005 Elsevier B.V. All rights reserved. |
S. Syafiie, F. Tadeo, E.C. Martínez Macro-actions in model-free intelligent control with application to pH control (Conferencia) 2005 , 2005, (cited By 0). (Resumen | Enlaces | BibTeX | Etiquetas: ) @conference{Syafiie20052710, title = {Macro-actions in model-free intelligent control with application to pH control}, author = { S. Syafiie and F. Tadeo and E.C. Martínez}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-33847201875&partnerID=40&md5=df39862236589181ef4f309d11808d2d}, doi = {10.1109/CDC.2005.1582572}, year = {2005}, date = {2005-01-01}, journal = {Proceedings of the 44th IEEE Conference on Decision and Control, and the European Control Conference, CDC-ECC '05}, volume = {2005}, pages = {2710-2715}, abstract = {MFIC (Model-Free Intelligent Control) is a technique, based on Reinforcement Learning, previously proposed by the authors to control processes without needing a precalculated model. In standard reinforcement learning algorithms (including MFIC), the interaction between an agent and the environment is based on a fixed time scale: during learning, the agent can select several primitive actions depending on the system state. This creates the problem of selecting a suitable fixed time scale to select control actions, to trade off accuracy in control against learning complexity and flexibility. A novel solution to this problem is presented in this paper: Macro-actions, that incorporate a general closed-loop policy and temporal extended actions. The application of macro actions on a laboratory plant of pH process shows that the proposed MFIC learns to control adequately the neutralization process, with reduced computational effort. © 2005 IEEE.}, note = {cited By 0}, keywords = {}, pubstate = {published}, tppubtype = {conference} } MFIC (Model-Free Intelligent Control) is a technique, based on Reinforcement Learning, previously proposed by the authors to control processes without needing a precalculated model. In standard reinforcement learning algorithms (including MFIC), the interaction between an agent and the environment is based on a fixed time scale: during learning, the agent can select several primitive actions depending on the system state. This creates the problem of selecting a suitable fixed time scale to select control actions, to trade off accuracy in control against learning complexity and flexibility. A novel solution to this problem is presented in this paper: Macro-actions, that incorporate a general closed-loop policy and temporal extended actions. The application of macro actions on a laboratory plant of pH process shows that the proposed MFIC learns to control adequately the neutralization process, with reduced computational effort. © 2005 IEEE. |
M.G. Cortés, E.G. Suárez, G. Corsano Cleaner technology through process integration on paper board production [Tecnología más limpia a través de la integración de procesos en la producción de papel para ondular] (Artículo de revista) Afinidad, 62 (520), pp. 584-588, 2005, (cited By 0). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Cortés2005584, title = {Cleaner technology through process integration on paper board production [Tecnología más limpia a través de la integración de procesos en la producción de papel para ondular]}, author = { M.G. Cortés and E.G. Suárez and G. Corsano}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-33745591904&partnerID=40&md5=5fe2c57f8653dbe4556f7ff6894344c2}, year = {2005}, date = {2005-01-01}, journal = {Afinidad}, volume = {62}, number = {520}, pages = {584-588}, abstract = {A methodology for the analysis and integration of process that allow the generation of wastes in the plant is developing, obtaining a more clean technology, which is applied in the solution of the technological y environmental problem of the industry of pulp and paper board. Its application in a factory of paper board, allow propose technological changes for the use of 45% of ethanol in base on dry fiber of sugar cane baggasse, as a solvent less aggressive to the environment, the consume of sodium hydroxide was reduced 1%, which diminish the aggressive effect of black liquor, the temperature was maintained in 175 °C and the de treatment time in 15 minutes, the same as do at industrial level. A reduction of 80% in the fresh water consume is obtained and the aqueous wastes reduction the environment. The impact of the technology is evaluated by a global model that quantified the obtained results in the technological, economical and environmental aspects.}, note = {cited By 0}, keywords = {}, pubstate = {published}, tppubtype = {article} } A methodology for the analysis and integration of process that allow the generation of wastes in the plant is developing, obtaining a more clean technology, which is applied in the solution of the technological y environmental problem of the industry of pulp and paper board. Its application in a factory of paper board, allow propose technological changes for the use of 45% of ethanol in base on dry fiber of sugar cane baggasse, as a solvent less aggressive to the environment, the consume of sodium hydroxide was reduced 1%, which diminish the aggressive effect of black liquor, the temperature was maintained in 175 °C and the de treatment time in 15 minutes, the same as do at industrial level. A reduction of 80% in the fresh water consume is obtained and the aqueous wastes reduction the environment. The impact of the technology is evaluated by a global model that quantified the obtained results in the technological, economical and environmental aspects. |
E.R. Henquín, J.M. Bisang Simplified model to predict the effect of the leakage current on primary and secondary current distributions in electrochemical reactors with a bipolar electrode (Artículo de revista) Journal of Applied Electrochemistry, 35 (12), pp. 1183-1190, 2005, (cited By 6). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Henquín20051183, title = {Simplified model to predict the effect of the leakage current on primary and secondary current distributions in electrochemical reactors with a bipolar electrode}, author = { E.R. Henquín and J.M. Bisang}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-29344447086&partnerID=40&md5=764566493b9d4218776f83d589cf47c3}, doi = {10.1007/s10800-005-9029-3}, year = {2005}, date = {2005-01-01}, journal = {Journal of Applied Electrochemistry}, volume = {35}, number = {12}, pages = {1183-1190}, abstract = {A simplified mathematical model to calculate the current distributions in bipolar electrochemical reactors is proposed. The current distributions are deduced from a combination of the voltage balance in the reactor with a voltage balance including the electrolyte inlet and outlet. Thus, equations to predict the effect of geometric and operational variables on the current distributions at the electrodes are reported. The parameters acting upon the current distributions were lumped into two dimensionless variables and their effects on the current distributions are discussed. The primary current distributions are obtained as a limiting case. Comparisons between calculated and experimental primary current distributions are reported. © Springer 2005.}, note = {cited By 6}, keywords = {}, pubstate = {published}, tppubtype = {article} } A simplified mathematical model to calculate the current distributions in bipolar electrochemical reactors is proposed. The current distributions are deduced from a combination of the voltage balance in the reactor with a voltage balance including the electrolyte inlet and outlet. Thus, equations to predict the effect of geometric and operational variables on the current distributions at the electrodes are reported. The parameters acting upon the current distributions were lumped into two dimensionless variables and their effects on the current distributions are discussed. The primary current distributions are obtained as a limiting case. Comparisons between calculated and experimental primary current distributions are reported. © Springer 2005. |
J. Espinosa, S. Brüggemann, W. Marquardt Application of the rectification body method to batch rectification (Artículo de revista) Computer Aided Chemical Engineering, 20 (C), pp. 757-762, 2005, (cited By 5). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Espinosa2005757, title = {Application of the rectification body method to batch rectification}, author = { J. Espinosa and S. Brüggemann and W. Marquardt}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-34548650022&partnerID=40&md5=53ca64386211a0d96c8e5668ab4775f2}, doi = {10.1016/S1570-7946(05)80248-2}, year = {2005}, date = {2005-01-01}, journal = {Computer Aided Chemical Engineering}, volume = {20}, number = {C}, pages = {757-762}, abstract = {This contribution focuses on the development of a dynamic conceptual model for a batch rectifier having an infinite number of stages without resorting to multistage calculations. For a given instantaneous still composition, the key feature of the method is the estimation of the instantaneous minimum reflux or the instantaneous distillate composition by using the Rectification Body Method. The usefulness of Bifurcation Analysis of pinch profiles is emphasized to model highly non-ideal behavior. © 2005 Elsevier B.V. All rights reserved.}, note = {cited By 5}, keywords = {}, pubstate = {published}, tppubtype = {article} } This contribution focuses on the development of a dynamic conceptual model for a batch rectifier having an infinite number of stages without resorting to multistage calculations. For a given instantaneous still composition, the key feature of the method is the estimation of the instantaneous minimum reflux or the instantaneous distillate composition by using the Rectification Body Method. The usefulness of Bifurcation Analysis of pinch profiles is emphasized to model highly non-ideal behavior. © 2005 Elsevier B.V. All rights reserved. |
P.D. Villarreal, E. Salomone, O.J. Chiotti Applying model-driven development to collaborative business processes (Conferencia) 2005, (cited By 0). (Resumen | Enlaces | BibTeX | Etiquetas: ) @conference{DavidVillarreal2005, title = {Applying model-driven development to collaborative business processes}, author = { P.D. Villarreal and E. Salomone and O.J. Chiotti}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84886711596&partnerID=40&md5=6ce2f7b9e43edbd71a7acebdf8cca82a}, year = {2005}, date = {2005-01-01}, journal = {Memorias de la 8th Conferencia Iberoamericana de Software Engineering - CIbSE 2005}, abstract = {Currently enterprises are focusing on the setting up of Business-to-Business collaborative relationships with their partners. One of the main challenges in these relationships is the definition of the Collaborative Business Processes. These processes have to be defined first in a business level using a technology-independent language, and then in a technological level using a Business-to-Business standard. Both definitions must have a mutual correspondence. Therefore, in this paper we present a model-driven development method to support the design of collaborative processes. As part of this method we describe the modeling language UP-ColBPIP to design technology-independent collaborative processes. This language supports the definition of these processes through interaction protocols. In addition, we provide a model transformation method that defines how from UP-ColBPIP collaborative process models we can generate specifications based on the ebXML standard for implementing collaborative processes.}, note = {cited By 0}, keywords = {}, pubstate = {published}, tppubtype = {conference} } Currently enterprises are focusing on the setting up of Business-to-Business collaborative relationships with their partners. One of the main challenges in these relationships is the definition of the Collaborative Business Processes. These processes have to be defined first in a business level using a technology-independent language, and then in a technological level using a Business-to-Business standard. Both definitions must have a mutual correspondence. Therefore, in this paper we present a model-driven development method to support the design of collaborative processes. As part of this method we describe the modeling language UP-ColBPIP to design technology-independent collaborative processes. This language supports the definition of these processes through interaction protocols. In addition, we provide a model transformation method that defines how from UP-ColBPIP collaborative process models we can generate specifications based on the ebXML standard for implementing collaborative processes. |
L. Caliusco, C. Maidana, M.R. Galli, O.J. Chiotti A language for modeling enterprise contextual ontologies (Conferencia) 160 , 2005, (cited By 0). (Resumen | Enlaces | BibTeX | Etiquetas: ) @conference{Caliusco2005, title = {A language for modeling enterprise contextual ontologies}, author = { L. Caliusco and C. Maidana and M.R. Galli and O.J. Chiotti}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84873470619&partnerID=40&md5=a7bfd187d378282b20745ee1c32aafd0}, year = {2005}, date = {2005-01-01}, journal = {CEUR Workshop Proceedings}, volume = {160}, abstract = {To achieve inter-enterprise software interoperability, the semantics of interchanged information by using electronic business documents, has to be explicitly modeled. A common approach to model semantics is to use an ontology. However, there is an emerging approach that combines an ontology with its context definition. So, the misunderstanding can be avoided if the context is explicitly defined. The resulting structure is called contextual ontology. To process a contextual ontology at run time, it has to be expressed in a machine procesable language. Recently, some languages have appeared. But, the main disadvantage of these languages is that they are mostly based on logic formalisms to support machine reasoning. Then, for the analysis and design phase of electronic business documents, a more appropriate contextual ontology modelling language is needed. To this aim, this paper presents a language for modelling explicit and formal contextual ontologies that assists business ontology designers in modelling contextual ontologies associated to electronic business documents.}, note = {cited By 0}, keywords = {}, pubstate = {published}, tppubtype = {conference} } To achieve inter-enterprise software interoperability, the semantics of interchanged information by using electronic business documents, has to be explicitly modeled. A common approach to model semantics is to use an ontology. However, there is an emerging approach that combines an ontology with its context definition. So, the misunderstanding can be avoided if the context is explicitly defined. The resulting structure is called contextual ontology. To process a contextual ontology at run time, it has to be expressed in a machine procesable language. Recently, some languages have appeared. But, the main disadvantage of these languages is that they are mostly based on logic formalisms to support machine reasoning. Then, for the analysis and design phase of electronic business documents, a more appropriate contextual ontology modelling language is needed. To this aim, this paper presents a language for modelling explicit and formal contextual ontologies that assists business ontology designers in modelling contextual ontologies associated to electronic business documents. |
G. Stegmayer, O.J. Chiotti Identification of frequency-domain Volterra model using neural networks (Artículo de revista) Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 3697 LNCS , pp. 465-471, 2005, (cited By 0). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Stegmayer2005465, title = {Identification of frequency-domain Volterra model using neural networks}, author = { G. Stegmayer and O.J. Chiotti}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-33646255227&partnerID=40&md5=602f06cb9bafaa11421eb11e75cdfaad}, year = {2005}, date = {2005-01-01}, journal = {Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)}, volume = {3697 LNCS}, pages = {465-471}, abstract = {In this paper, a new method is introduced for the identification of a Volterra model for the representation of a nonlinear electronic device in the frequency domain. The Volterra model is a numerical series with some particular terms named kernels. Our proposal is the use of feedforward neural networks (FNN) for the modeling of the nonlinearities in the device behavior, and a special procedure which uses the neural networks parameters for the kernels identification. The proposed procedure has been tested with simulation data from a class "A" Power Amplifier (PA) which validate our approach. © Springer-Verlag Berlin Heidelberg 2005.}, note = {cited By 0}, keywords = {}, pubstate = {published}, tppubtype = {article} } In this paper, a new method is introduced for the identification of a Volterra model for the representation of a nonlinear electronic device in the frequency domain. The Volterra model is a numerical series with some particular terms named kernels. Our proposal is the use of feedforward neural networks (FNN) for the modeling of the nonlinearities in the device behavior, and a special procedure which uses the neural networks parameters for the kernels identification. The proposed procedure has been tested with simulation data from a class "A" Power Amplifier (PA) which validate our approach. © Springer-Verlag Berlin Heidelberg 2005. |
G. Stegmayer, O.J. Chiotti Novel Neural Network application to nonlinear electronic devices modeling: Building a Volterra series model (Artículo de revista) Inteligencia Artificial, 9 (26), pp. 19-27, 2005, (cited By 0). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Stegmayer200519, title = {Novel Neural Network application to nonlinear electronic devices modeling: Building a Volterra series model}, author = { G. Stegmayer and O.J. Chiotti}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-33644943198&partnerID=40&md5=cdf435160c9778dedee40448273d4fef}, year = {2005}, date = {2005-01-01}, journal = {Inteligencia Artificial}, volume = {9}, number = {26}, pages = {19-27}, abstract = {In this work we want to present a novel application of Neural Networks as a Black-Box model, which allows representing the nonlinear behavior of a vast number of RF electronic devices with the Volterra series approximation. We propose a simple approach for the generation of the Volterra model for a device, even in the case of a nonlinearity that depends on more than one variable, which allows obtaining a general model, independent of the physical circuit. In particular, we will show the results obtained for the analysis of a transistor and the generation of its analytical Volterra series model, built using a standard Neural Network model and its parameters. © AEPIA.}, note = {cited By 0}, keywords = {}, pubstate = {published}, tppubtype = {article} } In this work we want to present a novel application of Neural Networks as a Black-Box model, which allows representing the nonlinear behavior of a vast number of RF electronic devices with the Volterra series approximation. We propose a simple approach for the generation of the Volterra model for a device, even in the case of a nonlinearity that depends on more than one variable, which allows obtaining a general model, independent of the physical circuit. In particular, we will show the results obtained for the analysis of a transistor and the generation of its analytical Volterra series model, built using a standard Neural Network model and its parameters. © AEPIA. |
M. Vegetti, S. Gonnet, G. Henning, H.P. Leone Information logistics for supply chain management within process industry environments (Artículo de revista) Computer Aided Chemical Engineering, 20 (C), pp. 1231-1236, 2005, (cited By 1). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Vegetti20051231, title = {Information logistics for supply chain management within process industry environments}, author = { M. Vegetti and S. Gonnet and G. Henning and H.P. Leone}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-77957112853&partnerID=40&md5=d092d39191df16d9fee02289ba1b3e6b}, doi = {10.1016/S1570-7946(05)80047-1}, year = {2005}, date = {2005-01-01}, journal = {Computer Aided Chemical Engineering}, volume = {20}, number = {C}, pages = {1231-1236}, abstract = {This contribution proposes the design of an ontology that provides the foundations for the specification of information logistics processes in extended supply chains associated to process industries. The proposed ontology includes concepts and relationships that are necessary to formally describe, measure and evaluate a supply chain (SC), thus simplifying the visualization and analysis of networks. A SC ontology is a first step towards achieving a standard description of SC design and management processes. © 2005 Elsevier B.V. All rights reserved.}, note = {cited By 1}, keywords = {}, pubstate = {published}, tppubtype = {article} } This contribution proposes the design of an ontology that provides the foundations for the specification of information logistics processes in extended supply chains associated to process industries. The proposed ontology includes concepts and relationships that are necessary to formally describe, measure and evaluate a supply chain (SC), thus simplifying the visualization and analysis of networks. A SC ontology is a first step towards achieving a standard description of SC design and management processes. © 2005 Elsevier B.V. All rights reserved. |
S.D. Zamar, H.E. Salomone, O.A. Iribarren Operation planning in the rectification of essential oils (Artículo de revista) Journal of Food Engineering, 69 (2), pp. 207-215, 2005, (cited By 4). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Zamar2005207, title = {Operation planning in the rectification of essential oils}, author = { S.D. Zamar and H.E. Salomone and O.A. Iribarren}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-14044265638&partnerID=40&md5=b63aae8ad5b8bb58116f74b5db778a15}, doi = {10.1016/j.jfoodeng.2004.07.019}, year = {2005}, date = {2005-01-01}, journal = {Journal of Food Engineering}, volume = {69}, number = {2}, pages = {207-215}, abstract = {This paper proposes a methodology that uses a recently developed shortcut model to represent each individual separation task, for planning the operation of a batch distillation column. For a given column and recycle policy, optimization of the recoveries of two key components at each separation renders the set of optimal reflux ratios and advances in each separation. The methodology is specially expedite for systems with a large number of components and whose performance can be upgraded by recycling intermediate cuts, as is the case in the rectification of essential oils. We illustrate the methodology by planning the rectification of crude orange oil to produce an oil essence depleted from light terpenes, which are responsible for rancidity of oils. © 2004 Elsevier Ltd. All rights reserved.}, note = {cited By 4}, keywords = {}, pubstate = {published}, tppubtype = {article} } This paper proposes a methodology that uses a recently developed shortcut model to represent each individual separation task, for planning the operation of a batch distillation column. For a given column and recycle policy, optimization of the recoveries of two key components at each separation renders the set of optimal reflux ratios and advances in each separation. The methodology is specially expedite for systems with a large number of components and whose performance can be upgraded by recycling intermediate cuts, as is the case in the rectification of essential oils. We illustrate the methodology by planning the rectification of crude orange oil to produce an oil essence depleted from light terpenes, which are responsible for rancidity of oils. © 2004 Elsevier Ltd. All rights reserved. |
M. Fuentes, M.C. Mussati, P.A. Aguirre, N.J. Scenna A three-phase fluidized bed anaerobic biofilm reactor model for treating complex substrates (Artículo de revista) Computer Aided Chemical Engineering, 20 (C), pp. 553-558, 2005, (cited By 0). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Fuentes2005553, title = {A three-phase fluidized bed anaerobic biofilm reactor model for treating complex substrates}, author = { M. Fuentes and M.C. Mussati and P.A. Aguirre and N.J. Scenna}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-77956770898&partnerID=40&md5=2bb168410027c63458c31819298d4c34}, doi = {10.1016/S1570-7946(05)80214-7}, year = {2005}, date = {2005-01-01}, journal = {Computer Aided Chemical Engineering}, volume = {20}, number = {C}, pages = {553-558}, abstract = {The main purpose of this paper is to present a model of a three-phase solid-liquid-gas system to investigate the hydrodynamic and biological behavior and performance of fluidized bed anaerobic biofilm reactors (FBABRs). A general one-dimensional axial dispersive dynamic model is proposed for computing the variation of the properties such as hold-ups and superficial velocities of all phases, biofilm thickness and biological and chemical specie concentrations. Biochemical transformations are assumed occurring only in the fluidized bed zone but not in the free-support material zone. The biofilm process model is coupled to the hydrodynamic model of the system through the biofilm detachment rate, which is assumed as a first-order function of the energy dissipation parameter. Non-active biomass is considered as particulate material subject to hydrolysis. A scheme of carbohydrate degradation, kinetic parameters accepted in the literature and design characteristics of a hypothetical FBABR are taken into account to show the model predictions. The performance of the FBABR is analyzed for different flow patterns through different dispersion coefficients for the phases. © 2005 Elsevier B.V. All rights reserved.}, note = {cited By 0}, keywords = {}, pubstate = {published}, tppubtype = {article} } The main purpose of this paper is to present a model of a three-phase solid-liquid-gas system to investigate the hydrodynamic and biological behavior and performance of fluidized bed anaerobic biofilm reactors (FBABRs). A general one-dimensional axial dispersive dynamic model is proposed for computing the variation of the properties such as hold-ups and superficial velocities of all phases, biofilm thickness and biological and chemical specie concentrations. Biochemical transformations are assumed occurring only in the fluidized bed zone but not in the free-support material zone. The biofilm process model is coupled to the hydrodynamic model of the system through the biofilm detachment rate, which is assumed as a first-order function of the energy dissipation parameter. Non-active biomass is considered as particulate material subject to hydrolysis. A scheme of carbohydrate degradation, kinetic parameters accepted in the literature and design characteristics of a hypothetical FBABR are taken into account to show the model predictions. The performance of the FBABR is analyzed for different flow patterns through different dispersion coefficients for the phases. © 2005 Elsevier B.V. All rights reserved. |
S.F. Mussati, P.A. Aguirre, N.J. Scenna Optimization of alternative structures of integrated power and desalination plants (Artículo de revista) Desalination, 182 (1-3), pp. 123-129, 2005, (cited By 11). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Mussati2005123, title = {Optimization of alternative structures of integrated power and desalination plants}, author = { S.F. Mussati and P.A. Aguirre and N.J. Scenna}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-27944444533&partnerID=40&md5=c7789f399df95e6baf72b3cbbe9ef389}, doi = {10.1016/j.desal.2005.03.012}, year = {2005}, date = {2005-01-01}, journal = {Desalination}, volume = {182}, number = {1-3}, pages = {123-129}, abstract = {The selection of a dual purpose desalination plant depend mainly on many factors such as the required power to water ratio, cost of fuel energy charged to the desalting process, electricity sales, capital costs, and local requirements. Alternative configurations must be analyzed in order to select the optimal configuration to satisfy electricity and fresh water demands. This paper presents an optimization mathematical model of a superstructure of alternative configurations of dual purpose desalination plants (DPP). In fact, the mathematical model recently proposed by [1] has been properly modified in order to include other alternative arrangements. The proposed alternative configurations reduce significantly the total levelled cost of the DPP. The superstructure of optional arrangements (optimization problem) is modelled as a Mixed Integer Nonlinear Programming (MINLP) Model where binary variables (0-1) are used to select the equipments for the cogeneration plant. The resulting MINLP mathematical model can be used for synthesis as well as for analyzing different design alternatives. The solution obtained by the proposed mathematical model provides the basic design of the DPP. The model has been implemented in General Algebraic Modelling System [2]. Several study cases were successfully solved by applying the MINLP model. In this paper a study case is presented in order to illustrate the model capabilities. © 2005 Elsevier B.V. All rights reserved.}, note = {cited By 11}, keywords = {}, pubstate = {published}, tppubtype = {article} } The selection of a dual purpose desalination plant depend mainly on many factors such as the required power to water ratio, cost of fuel energy charged to the desalting process, electricity sales, capital costs, and local requirements. Alternative configurations must be analyzed in order to select the optimal configuration to satisfy electricity and fresh water demands. This paper presents an optimization mathematical model of a superstructure of alternative configurations of dual purpose desalination plants (DPP). In fact, the mathematical model recently proposed by [1] has been properly modified in order to include other alternative arrangements. The proposed alternative configurations reduce significantly the total levelled cost of the DPP. The superstructure of optional arrangements (optimization problem) is modelled as a Mixed Integer Nonlinear Programming (MINLP) Model where binary variables (0-1) are used to select the equipments for the cogeneration plant. The resulting MINLP mathematical model can be used for synthesis as well as for analyzing different design alternatives. The solution obtained by the proposed mathematical model provides the basic design of the DPP. The model has been implemented in General Algebraic Modelling System [2]. Several study cases were successfully solved by applying the MINLP model. In this paper a study case is presented in order to illustrate the model capabilities. © 2005 Elsevier B.V. All rights reserved. |
M.G. Marcovecchio, S.F. Mussati, P.A. Aguirre, N.J. Scenna Optimization of hybrid desalination processes including multi stage flash and reverse osmosis systems (Artículo de revista) Desalination, 182 (1-3), pp. 111-122, 2005, (cited By 33). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Marcovecchio2005111, title = {Optimization of hybrid desalination processes including multi stage flash and reverse osmosis systems}, author = { M.G. Marcovecchio and S.F. Mussati and P.A. Aguirre and N.J. Scenna}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-27944438470&partnerID=40&md5=1379cbc980d68465b98ee17219943d1b}, doi = {10.1016/j.desal.2005.03.011}, year = {2005}, date = {2005-01-01}, journal = {Desalination}, volume = {182}, number = {1-3}, pages = {111-122}, abstract = {This paper addresses an optimization model of Hybrid Desalination Processes including MSF and RO systems. Desalination is the process of removing salt and other minerals or chemicals from seawater and it is one of the alternative sources for fresh water available today. Desalination provides water for domestic purposes, industrial processing, agricultural irrigation, etc. The most conventional desalination technologies are membrane processes (Reverse Osmosis RO) and Thermal Desalination (Multi Stage Flash - MSF-and Multi Effect Evaporation - MEE-systems). Hybrid RO-MSF desalination systems have potential advantages of a higher overall availability, low power demand, and improved water quality. In this paper a mathematical model of a hybrid desalination plant including MSF(OT) and RO process is presented. The objective is to determine the optimal process design and operating conditions for a given water production. Both RO and MSF systems are modeled in a rigorous way. The resulting mathematical model contains inherently nonlinear and non-convex constraints. The solution obtained by the proposed mathematical model provides the basic design of the hybrid MSF(OT)-RO desalination plant. A case study is presented to illustrate the application of the proposed model. © 2005 Elsevier B.V. All rights reserved.}, note = {cited By 33}, keywords = {}, pubstate = {published}, tppubtype = {article} } This paper addresses an optimization model of Hybrid Desalination Processes including MSF and RO systems. Desalination is the process of removing salt and other minerals or chemicals from seawater and it is one of the alternative sources for fresh water available today. Desalination provides water for domestic purposes, industrial processing, agricultural irrigation, etc. The most conventional desalination technologies are membrane processes (Reverse Osmosis RO) and Thermal Desalination (Multi Stage Flash - MSF-and Multi Effect Evaporation - MEE-systems). Hybrid RO-MSF desalination systems have potential advantages of a higher overall availability, low power demand, and improved water quality. In this paper a mathematical model of a hybrid desalination plant including MSF(OT) and RO process is presented. The objective is to determine the optimal process design and operating conditions for a given water production. Both RO and MSF systems are modeled in a rigorous way. The resulting mathematical model contains inherently nonlinear and non-convex constraints. The solution obtained by the proposed mathematical model provides the basic design of the hybrid MSF(OT)-RO desalination plant. A case study is presented to illustrate the application of the proposed model. © 2005 Elsevier B.V. All rights reserved. |
M.G. Marcovecchio, P.A. Aguirre, N.J. Scenna Global optimal design of reverse osmosis networks for seawater desalination: Modeling and algorithm (Artículo de revista) Desalination, 184 (1-3), pp. 259-271, 2005, (cited By 57). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Marcovecchio2005259, title = {Global optimal design of reverse osmosis networks for seawater desalination: Modeling and algorithm}, author = { M.G. Marcovecchio and P.A. Aguirre and N.J. Scenna}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-27944462621&partnerID=40&md5=bddc9fbcfddc0b44b9ea4dfde56d1447}, doi = {10.1016/j.desal.2005.03.056}, year = {2005}, date = {2005-01-01}, journal = {Desalination}, volume = {184}, number = {1-3}, pages = {259-271}, abstract = {A novel global optimization algorithm to solve nonconvex problem is used to find the global optimal design of reverse osmosis networks for seawater desalination. The objective is to determine the optimal process design and operating conditions for a given water production. The networks were designed by using hollow fiber reverse osmosis modules. The Kimura-Sourirajan model was used for describing transport phenomena of solute and water transport through the membrane. The concentration polarization phenomenon has been taken into account. It was mathematically described using the film theory. The objective function to be minimized is the cost, which includes capital investment (membrane cost, pumping and energy recovery system, intake and pre-treatment systems, etc.) and operation and maintenance costs (membrane replacement, chemical treatment, spares, required and recovered energy, etc.). The proposed algorithm is deterministic and attains finite convergence to the global optimum. It is iterative and a main problem is solved each iteration. The main problem has convex constraints and a nonconvex objective function. The main problem solution indicates either a better solution for the original problem, or a region which can be discarded. Therefore, the feasible region to improve the objective function is reduced each iteration. The algorithm finishes when the whole region has been analysed and discarded. A bound reduction technique is performed in order to accelerate the convergence speed. The algorithm shows a good performance and efficient execution time. Different cases are solved in order to show the methodology and computational performance. © 2005 Elsevier B.V. All rights reserved.}, note = {cited By 57}, keywords = {}, pubstate = {published}, tppubtype = {article} } A novel global optimization algorithm to solve nonconvex problem is used to find the global optimal design of reverse osmosis networks for seawater desalination. The objective is to determine the optimal process design and operating conditions for a given water production. The networks were designed by using hollow fiber reverse osmosis modules. The Kimura-Sourirajan model was used for describing transport phenomena of solute and water transport through the membrane. The concentration polarization phenomenon has been taken into account. It was mathematically described using the film theory. The objective function to be minimized is the cost, which includes capital investment (membrane cost, pumping and energy recovery system, intake and pre-treatment systems, etc.) and operation and maintenance costs (membrane replacement, chemical treatment, spares, required and recovered energy, etc.). The proposed algorithm is deterministic and attains finite convergence to the global optimum. It is iterative and a main problem is solved each iteration. The main problem has convex constraints and a nonconvex objective function. The main problem solution indicates either a better solution for the original problem, or a region which can be discarded. Therefore, the feasible region to improve the objective function is reduced each iteration. The algorithm finishes when the whole region has been analysed and discarded. A bound reduction technique is performed in order to accelerate the convergence speed. The algorithm shows a good performance and efficient execution time. Different cases are solved in order to show the methodology and computational performance. © 2005 Elsevier B.V. All rights reserved. |
M.C. Mussati, M. Fuentes, P.A. Aguirre, N.J. Scenna A steady-state module for modeling anaerobic biofilm reactors (Artículo de revista) Latin American Applied Research, 35 (4), pp. 255-263, 2005, (cited By 4). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Mussati2005255, title = {A steady-state module for modeling anaerobic biofilm reactors}, author = { M.C. Mussati and M. Fuentes and P.A. Aguirre and N.J. Scenna}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-27744569968&partnerID=40&md5=7e44cc51a0bacd0214ad1b8607a6f98c}, year = {2005}, date = {2005-01-01}, journal = {Latin American Applied Research}, volume = {35}, number = {4}, pages = {255-263}, abstract = {A steady state model of an anaerobic methanogenic biofilm reactor-module that accounts for the biological interactions of four microbial groups, ionic equilibrium in solution, gas-liquid transfer phenomena and biofilm processes is presented. The model consists of a continuous stirred tank reactor type that allocates an inert support material, whose specific surface is taken into account. The biofilm model assumes an homogeneous biofilm of uniform thickness and constant density with no mass transfer resistance. The biofilm detachment process rate is modeled as a second-order function on the biofilm thickness and a first-order function on the mass fraction of the fixed biomass concentration of each microbial group. The balance equations for non-active biomass in liquid and biofilm are included. The model predictions have been satisfactorily compared with steady state experimental data reported in literature from a one-phase methanogenic biofilm system treating an acetic acid-based synthetic effluent, and a two-phase system with combined suspended (acidogenic) and attached (methanogenic) microbial growth treating a food industry wastewater composed by two residual process streams.}, note = {cited By 4}, keywords = {}, pubstate = {published}, tppubtype = {article} } A steady state model of an anaerobic methanogenic biofilm reactor-module that accounts for the biological interactions of four microbial groups, ionic equilibrium in solution, gas-liquid transfer phenomena and biofilm processes is presented. The model consists of a continuous stirred tank reactor type that allocates an inert support material, whose specific surface is taken into account. The biofilm model assumes an homogeneous biofilm of uniform thickness and constant density with no mass transfer resistance. The biofilm detachment process rate is modeled as a second-order function on the biofilm thickness and a first-order function on the mass fraction of the fixed biomass concentration of each microbial group. The balance equations for non-active biomass in liquid and biofilm are included. The model predictions have been satisfactorily compared with steady state experimental data reported in literature from a one-phase methanogenic biofilm system treating an acetic acid-based synthetic effluent, and a two-phase system with combined suspended (acidogenic) and attached (methanogenic) microbial growth treating a food industry wastewater composed by two residual process streams. |
M.C. Mussati, C. Thompson, M. Fuentes, P.A. Aguirre, N. Scenna Characteristics of a methanogenic biofilm on sand particles in a fluidized bed reactor (Artículo de revista) Latin American Applied Research, 35 (4), pp. 265-272, 2005, (cited By 7). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Mussati2005265, title = {Characteristics of a methanogenic biofilm on sand particles in a fluidized bed reactor}, author = { M.C. Mussati and C. Thompson and M. Fuentes and P.A. Aguirre and N. Scenna}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-27744574737&partnerID=40&md5=fd911fcd8f233c0518c8fd7325cedbda}, year = {2005}, date = {2005-01-01}, journal = {Latin American Applied Research}, volume = {35}, number = {4}, pages = {265-272}, abstract = {The typical microbiological groups reported in literature under the experienced environmental conditions are present in the biofilm structure investigated on sand particles. This is concluded based on microorganism morphology analyzed by scanning electron microscopy. Methanosarcina sp. (acetate consumers) and filamentous microorganisms with morphology similar to Methanospirillum sp. (H2-utilizing archaea) are distinguished among methanogens. Based on acetate levels and microorganism's threshold concentration, a predominance of Methanosarcina mazei rather than Methanosarcina barkeri is concluded Among acetogens, bacillus morphologically similar to the syntrophic acetogenic Syntrophobacter wolinii are observed together with Desulfovibrio sp. (hydrogen-utilizing, sulfate-reducing). With respect to acidogens, short and long rod-shaped bacteria, diplococcus in chains (probably Streptococcus-like bacteria) and filamentous bacilli are morphologically distinguished but cannot be characterized from this study. A methanogenic biofilm fluidized bed reactor inoculated with the biofilm population investigated showed process efficiencies up to 98% of chemical oxygen demand reduction for treating an acetate-based substrate.}, note = {cited By 7}, keywords = {}, pubstate = {published}, tppubtype = {article} } The typical microbiological groups reported in literature under the experienced environmental conditions are present in the biofilm structure investigated on sand particles. This is concluded based on microorganism morphology analyzed by scanning electron microscopy. Methanosarcina sp. (acetate consumers) and filamentous microorganisms with morphology similar to Methanospirillum sp. (H2-utilizing archaea) are distinguished among methanogens. Based on acetate levels and microorganism's threshold concentration, a predominance of Methanosarcina mazei rather than Methanosarcina barkeri is concluded Among acetogens, bacillus morphologically similar to the syntrophic acetogenic Syntrophobacter wolinii are observed together with Desulfovibrio sp. (hydrogen-utilizing, sulfate-reducing). With respect to acidogens, short and long rod-shaped bacteria, diplococcus in chains (probably Streptococcus-like bacteria) and filamentous bacilli are morphologically distinguished but cannot be characterized from this study. A methanogenic biofilm fluidized bed reactor inoculated with the biofilm population investigated showed process efficiencies up to 98% of chemical oxygen demand reduction for treating an acetate-based substrate. |
M.L. Bergamini, P.A. Aguirre, I. Grossmann Logic-based outer approximation for globally optimal synthesis of process networks (Artículo de revista) Computers and Chemical Engineering, 29 (9), pp. 1914-1933, 2005, (cited By 45). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Bergamini20051914, title = {Logic-based outer approximation for globally optimal synthesis of process networks}, author = { M.L. Bergamini and P.A. Aguirre and I. Grossmann}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-24144473642&partnerID=40&md5=412e3d60fdc73cf11563cd33b98724cf}, doi = {10.1016/j.compchemeng.2005.04.003}, year = {2005}, date = {2005-01-01}, journal = {Computers and Chemical Engineering}, volume = {29}, number = {9}, pages = {1914-1933}, abstract = {Process network problems can be formulated as generalized disjunctive programs where a logic-based representation is used to deal with the discrete and continuous decisions. A new deterministic algorithm for the global optimization of process networks is presented in this work. The proposed algorithm, which does not rely on spatial branch-and-bound, is based on the logic-based outer approximation that exploits the special structure of flowsheet synthesis models. The method is capable of considering non-convexities, while guaranteeing globality in the solution of an optimal synthesis of process network problem. This is accomplished by solving iteratively reduced NLP subproblems to global optimality and MILP master problems, which are valid outer approximations of the original problem. Piecewise linear under and overestimators for bilinear and concave terms have been constructed with the property of having zero gap in a finite set of points. The global optimization of the reduced NLP may be performed either with a suitable global solver or using the inner optimization strategy that is proposed in this work. Theoretical properties are discussed as well as several alternatives for implementing the proposed algorithm. Several examples were successfully solved with this algorithm. Results show that only few iterations are required to solve them to global optimality. © 2005 Elsevier Ltd. All rights reserved.}, note = {cited By 45}, keywords = {}, pubstate = {published}, tppubtype = {article} } Process network problems can be formulated as generalized disjunctive programs where a logic-based representation is used to deal with the discrete and continuous decisions. A new deterministic algorithm for the global optimization of process networks is presented in this work. The proposed algorithm, which does not rely on spatial branch-and-bound, is based on the logic-based outer approximation that exploits the special structure of flowsheet synthesis models. The method is capable of considering non-convexities, while guaranteeing globality in the solution of an optimal synthesis of process network problem. This is accomplished by solving iteratively reduced NLP subproblems to global optimality and MILP master problems, which are valid outer approximations of the original problem. Piecewise linear under and overestimators for bilinear and concave terms have been constructed with the property of having zero gap in a finite set of points. The global optimization of the reduced NLP may be performed either with a suitable global solver or using the inner optimization strategy that is proposed in this work. Theoretical properties are discussed as well as several alternatives for implementing the proposed algorithm. Several examples were successfully solved with this algorithm. Results show that only few iterations are required to solve them to global optimality. © 2005 Elsevier Ltd. All rights reserved. |
I.E. Grossmann, P.A. Aguirre, M. Barttfeld Optimal synthesis of complex distillation columns using rigorous models (Artículo de revista) Computers and Chemical Engineering, 29 (6 SPEC. ISS.), pp. 1203-1215, 2005, (cited By 42). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Grossmann20051203, title = {Optimal synthesis of complex distillation columns using rigorous models}, author = { I.E. Grossmann and P.A. Aguirre and M. Barttfeld}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-18244381777&partnerID=40&md5=4590f9b549a9c6f49366e7fa2e8629ee}, doi = {10.1016/j.compchemeng.2005.02.030}, year = {2005}, date = {2005-01-01}, journal = {Computers and Chemical Engineering}, volume = {29}, number = {6 SPEC. ISS.}, pages = {1203-1215}, abstract = {The synthesis of complex distillation columns has remained a major challenge since the pioneering work by [Sargent, R.W.H., & Gaminibandara, K. (1976). Optimal design of plate distillation columns. In L.C.W. Dixon (Ed.), Optimization in action. New York: Academic Press]. In this paper, we first provide a review of recent work for the optimal design of distillation of individual columns using tray-by-tray models. We examine the impact of different representations and models, NLP, mixed-integer nonlinear programming (MINLP) and generalized disjunctive programming (GDP), as well as the importance of appropriate initialization schemes. We next provide a review of the synthesis of complex column configurations for zeotropic mixtures and discuss different superstructure representations as well as decomposition schemes for tackling these problems. Finally, we briefly discuss extensions for handling azeotropic mixtures. Numerical examples are presented to demonstrate that effective computational strategies are emerging that are based on disjunctive programming models that are coupled with thermodynamic initialization models and integrated through hierarchical decomposition techniques. © 2005 Elsevier Ltd. All rights reserved.}, note = {cited By 42}, keywords = {}, pubstate = {published}, tppubtype = {article} } The synthesis of complex distillation columns has remained a major challenge since the pioneering work by [Sargent, R.W.H., & Gaminibandara, K. (1976). Optimal design of plate distillation columns. In L.C.W. Dixon (Ed.), Optimization in action. New York: Academic Press]. In this paper, we first provide a review of recent work for the optimal design of distillation of individual columns using tray-by-tray models. We examine the impact of different representations and models, NLP, mixed-integer nonlinear programming (MINLP) and generalized disjunctive programming (GDP), as well as the importance of appropriate initialization schemes. We next provide a review of the synthesis of complex column configurations for zeotropic mixtures and discuss different superstructure representations as well as decomposition schemes for tackling these problems. Finally, we briefly discuss extensions for handling azeotropic mixtures. Numerical examples are presented to demonstrate that effective computational strategies are emerging that are based on disjunctive programming models that are coupled with thermodynamic initialization models and integrated through hierarchical decomposition techniques. © 2005 Elsevier Ltd. All rights reserved. |
J.M. Montagna A framework for the assessment and analysis of electronic government proposals (Artículo de revista) Electronic Commerce Research and Applications, 4 (3), pp. 204-219, 2005, (cited By 50). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Montagna2005204, title = {A framework for the assessment and analysis of electronic government proposals}, author = { J.M. Montagna}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-23144455215&partnerID=40&md5=6cd7cb4c33ff3ac21afb55c1b9393348}, doi = {10.1016/j.elerap.2005.01.003}, year = {2005}, date = {2005-01-01}, journal = {Electronic Commerce Research and Applications}, volume = {4}, number = {3}, pages = {204-219}, abstract = {Electronic government or e-government arises as the way to integrate all Internet and computer networks potentialities into public administration. However, there are many technical, organizational and institutional elements to be considered when making a decision of this kind. These elements prevent decision makers from quickly and efficiently analyzing the critical points to approve an initiative related to e-government. This work presents basic criteria for evaluating specific projects in the context of an electronic government policy. These criteria give rise to a very simple framework that allows determining the elements that support an e-government proposal for the various alternatives in which it may appear: in relation to citizens, to the business environment, or to other government areas. This work considers the grounds for determining electronic government action performance to assess the advantages and benefits that specific proposals can provide to government and society. © 2005 Elsevier B.V. All rights reserved.}, note = {cited By 50}, keywords = {}, pubstate = {published}, tppubtype = {article} } Electronic government or e-government arises as the way to integrate all Internet and computer networks potentialities into public administration. However, there are many technical, organizational and institutional elements to be considered when making a decision of this kind. These elements prevent decision makers from quickly and efficiently analyzing the critical points to approve an initiative related to e-government. This work presents basic criteria for evaluating specific projects in the context of an electronic government policy. These criteria give rise to a very simple framework that allows determining the elements that support an e-government proposal for the various alternatives in which it may appear: in relation to citizens, to the business environment, or to other government areas. This work considers the grounds for determining electronic government action performance to assess the advantages and benefits that specific proposals can provide to government and society. © 2005 Elsevier B.V. All rights reserved. |
2004 |
E.C. Martínez, C.d.P. Moraga Reasoning and planning with means-ends models in abnormal situation management (Artículo de revista) Computer Aided Chemical Engineering, 18 (C), pp. 961-966, 2004, (cited By 0). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Martínez2004961, title = {Reasoning and planning with means-ends models in abnormal situation management}, author = { E.C. Martínez and C.d.P. Moraga}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-77955646922&partnerID=40&md5=ca3e7ccec4605ddd7fbeac9672d858b3}, doi = {10.1016/S1570-7946(04)80226-8}, year = {2004}, date = {2004-01-01}, journal = {Computer Aided Chemical Engineering}, volume = {18}, number = {C}, pages = {961-966}, abstract = {Mismanagement of abnormal operating conditions has a very costly, yet avoidable impact for the Chemical Process Industry. For abnormal situation management (ASM) is key to assess quickly the plant situation and develop a plan on-line either to restore normal operation or to bring the process to a safe state. This paper addresses the important issue of including a teleological (intentional) dimension in process modelling for ASM by explicitly relating process components to functions and goals that must be achieved. A formal modelling framework that resort to means (functions and components) and ends (a hierarchy of goals) to distinguish between normal and abnormal situations, to reason about goal achievement, to trace the causes of a unit malfunction and to plan a course of action is presented. The means-ends model (MEM) is expressed as logical axioms in a knowledge base using situations calculus. This formal representation of a MEM allows continuously assessing plant situations, doing queries about the state of goals and functions, and testing alternative course of actions for feasibility and performance. © 2004 Elsevier B.V. All rights reserved.}, note = {cited By 0}, keywords = {}, pubstate = {published}, tppubtype = {article} } Mismanagement of abnormal operating conditions has a very costly, yet avoidable impact for the Chemical Process Industry. For abnormal situation management (ASM) is key to assess quickly the plant situation and develop a plan on-line either to restore normal operation or to bring the process to a safe state. This paper addresses the important issue of including a teleological (intentional) dimension in process modelling for ASM by explicitly relating process components to functions and goals that must be achieved. A formal modelling framework that resort to means (functions and components) and ends (a hierarchy of goals) to distinguish between normal and abnormal situations, to reason about goal achievement, to trace the causes of a unit malfunction and to plan a course of action is presented. The means-ends model (MEM) is expressed as logical axioms in a knowledge base using situations calculus. This formal representation of a MEM allows continuously assessing plant situations, doing queries about the state of goals and functions, and testing alternative course of actions for feasibility and performance. © 2004 Elsevier B.V. All rights reserved. |
A. Assandri, A. Rueda, E.C. Martínez, C.d. Prada Integration of a reduced first-principles model in predictive control of a complex distillation column (Artículo de revista) Computer Aided Chemical Engineering, 18 (C), pp. 559-564, 2004, (cited By 1). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Assandri2004559, title = {Integration of a reduced first-principles model in predictive control of a complex distillation column}, author = { A. Assandri and A. Rueda and E.C. Martínez and C.d. Prada}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-77955620616&partnerID=40&md5=147c75977957b51e7d5675bafb9eac25}, doi = {10.1016/S1570-7946(04)80159-7}, year = {2004}, date = {2004-01-01}, journal = {Computer Aided Chemical Engineering}, volume = {18}, number = {C}, pages = {559-564}, abstract = {As operating conditions are changed continuously driven by the economic optimization layer, performance problems in the regulatory layer due to poor tuning escalate. These performance problems prevent reaping off most of the potential economic gains of realtime optimization. In this work, the integration of a reduced process model with Parametric Predictive Control (PPC) is discussed for bottom temperature control of a distillation column. The obtained control law is very simple to implement and exhibits excellent performance over a wide range of operating conditions without any need for retuning. Disturbances that have been studied include changes to the composition and temperature in the column feed and to the internal reflux flow rate. The use of a state estimator to compensate for modelling errors is discussed. Results obtained are very encouraging and an industrial implementation of the controller is currently underway. © 2004 Elsevier B.V. All rights reserved.}, note = {cited By 1}, keywords = {}, pubstate = {published}, tppubtype = {article} } As operating conditions are changed continuously driven by the economic optimization layer, performance problems in the regulatory layer due to poor tuning escalate. These performance problems prevent reaping off most of the potential economic gains of realtime optimization. In this work, the integration of a reduced process model with Parametric Predictive Control (PPC) is discussed for bottom temperature control of a distillation column. The obtained control law is very simple to implement and exhibits excellent performance over a wide range of operating conditions without any need for retuning. Disturbances that have been studied include changes to the composition and temperature in the column feed and to the internal reflux flow rate. The use of a state estimator to compensate for modelling errors is discussed. Results obtained are very encouraging and an industrial implementation of the controller is currently underway. © 2004 Elsevier B.V. All rights reserved. |
S. Syafiie, F. Tadeo, E.C. Martínez Learning control application to nonlinear process control (Conferencia) 2004, (cited By 0). (Resumen | Enlaces | BibTeX | Etiquetas: ) @conference{Syafiie2004260, title = {Learning control application to nonlinear process control}, author = { S. Syafiie and F. Tadeo and E.C. Martínez}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-32844465214&partnerID=40&md5=6e21c4811c7488816a63ae3b70c9781b}, year = {2004}, date = {2004-01-01}, journal = {Intelligent Automation and Control Trends, Principles, and Applications - Proceedings of the Sixth Biannual World Automation Congress, WAC}, pages = {260-265}, abstract = {This paper presents the application of Reinforcement Learning to nonlinear process control. Reinforcement Learning is a model-free technique based on online learning without supervision, with the objective of optimizing a cumulative future reward by resorting to experimentation with the system. The One-step-ahead Q-learning look-up table of reinforcement Learning Method is applied to a model of a pH neutralization process. Control actions are selected using the ε-greedy and softmax policies. The application shows the ability of the proposed method to control chemical processes with difficult, unknown or time-varying dynamics.}, note = {cited By 0}, keywords = {}, pubstate = {published}, tppubtype = {conference} } This paper presents the application of Reinforcement Learning to nonlinear process control. Reinforcement Learning is a model-free technique based on online learning without supervision, with the objective of optimizing a cumulative future reward by resorting to experimentation with the system. The One-step-ahead Q-learning look-up table of reinforcement Learning Method is applied to a model of a pH neutralization process. Control actions are selected using the ε-greedy and softmax policies. The application shows the ability of the proposed method to control chemical processes with difficult, unknown or time-varying dynamics. |
S.J. Benz, J.A. Francesconi, N.J. Scenna Strategies for starting up azeotropic distillation columns with multiple steady states (Artículo de revista) Canadian Journal of Chemical Engineering, 82 (5), pp. 920-929, 2004, (cited By 3). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Benz2004920, title = {Strategies for starting up azeotropic distillation columns with multiple steady states}, author = { S.J. Benz and J.A. Francesconi and N.J. Scenna}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-13844296406&partnerID=40&md5=7f0659062a9e308d604bc3df7f273977}, year = {2004}, date = {2004-01-01}, journal = {Canadian Journal of Chemical Engineering}, volume = {82}, number = {5}, pages = {920-929}, abstract = {The operability of azeotropic distillation columns with multiplicity is analysed during start-up by dynamic simulation. Different steady states can be reached by applying different start-up configurations and/or policies. The well-known benzene-heptane-acetone (BHA) system is studied. The process by which the column reaches these steady states can be seen through the examination of profile evolutions corresponding to the given start-up policies. Indeed, a clear partition of the start-up policies space yielding different solutions is achieved. Some properties of this space are explained and start-up critical values can be identified. Finally, some guidelines for start-up supervision are outlined for the study case.}, note = {cited By 3}, keywords = {}, pubstate = {published}, tppubtype = {article} } The operability of azeotropic distillation columns with multiplicity is analysed during start-up by dynamic simulation. Different steady states can be reached by applying different start-up configurations and/or policies. The well-known benzene-heptane-acetone (BHA) system is studied. The process by which the column reaches these steady states can be seen through the examination of profile evolutions corresponding to the given start-up policies. Indeed, a clear partition of the start-up policies space yielding different solutions is achieved. Some properties of this space are explained and start-up critical values can be identified. Finally, some guidelines for start-up supervision are outlined for the study case. |
N.J. Scenna, S.J. Benz, J.A. Francesconi, N.H. Rodríguez Start-up of Homogeneous Azeotropic Distillation Columns with Multiple Steady States (Artículo de revista) Industrial and Engineering Chemistry Research, 43 (2), pp. 553-565, 2004, (cited By 4). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Scenna2004553, title = {Start-up of Homogeneous Azeotropic Distillation Columns with Multiple Steady States}, author = { N.J. Scenna and S.J. Benz and J.A. Francesconi and N.H. Rodríguez}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-0345866689&partnerID=40&md5=e91e04242bf8512fe756b20f665c5716}, year = {2004}, date = {2004-01-01}, journal = {Industrial and Engineering Chemistry Research}, volume = {43}, number = {2}, pages = {553-565}, abstract = {The impact of different start-up procedures on the behavior of two azeotropic distillation columns with multiple steady states is analyzed. Several dynamic simulation results for the two study cases are presented. Through an examination of the profile evolutions corresponding to given open-loop start-up policies (manual start-up strategies), it can be seen how the column arrives at different steady states as a function of the start-up policy. This shows that it is possible to identify a set of critical values for supervision of the start-up. Also, guidelines of general validity are given with the aim of finding the appropriate start-up policy for obtaining a desired solution. A mechanistic (qualitative) approach is presented for the interpretation of the system behavior. Some connections among the system responses and the phenomenon of multiplicity are presented. Also, a quantitative, semiempirical relationship is introduced to corroborate the qualitative explanation of the system responses. Finally, closed-loop start-up policies using a simple PI controller are analyzed, showing that the desired steady state can always be achieved in these cases.}, note = {cited By 4}, keywords = {}, pubstate = {published}, tppubtype = {article} } The impact of different start-up procedures on the behavior of two azeotropic distillation columns with multiple steady states is analyzed. Several dynamic simulation results for the two study cases are presented. Through an examination of the profile evolutions corresponding to given open-loop start-up policies (manual start-up strategies), it can be seen how the column arrives at different steady states as a function of the start-up policy. This shows that it is possible to identify a set of critical values for supervision of the start-up. Also, guidelines of general validity are given with the aim of finding the appropriate start-up policy for obtaining a desired solution. A mechanistic (qualitative) approach is presented for the interpretation of the system behavior. Some connections among the system responses and the phenomenon of multiplicity are presented. Also, a quantitative, semiempirical relationship is introduced to corroborate the qualitative explanation of the system responses. Finally, closed-loop start-up policies using a simple PI controller are analyzed, showing that the desired steady state can always be achieved in these cases. |
S. Gonnet, H.P. Leone, G. Henning An integrated model for capturing the process design process (Artículo de revista) Computer Aided Chemical Engineering, 18 (C), pp. 415-420, 2004, (cited By 0). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Gonnet2004415, title = {An integrated model for capturing the process design process}, author = { S. Gonnet and H.P. Leone and G. Henning}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-77955614908&partnerID=40&md5=fedfdf1e4ff7425d7a1eccc34ae4c5e3}, doi = {10.1016/S1570-7946(04)80135-4}, year = {2004}, date = {2004-01-01}, journal = {Computer Aided Chemical Engineering}, volume = {18}, number = {C}, pages = {415-420}, abstract = {This paper presents an integrated deductive object-oriented model that, in relation to a design process, is able to capture (i) the activities, operations and actors that have generated each design product, (ii) the imposed requirements as well as (iii) the rationale behind each adopted decision. Furthermore, it also offers an explicit mechanism to manage the different model versions that have participated during the design process. Thus, the proposed model allows the tracing of such design process and its resulting products. © 2004 Elsevier B.V. All rights reserved.}, note = {cited By 0}, keywords = {}, pubstate = {published}, tppubtype = {article} } This paper presents an integrated deductive object-oriented model that, in relation to a design process, is able to capture (i) the activities, operations and actors that have generated each design product, (ii) the imposed requirements as well as (iii) the rationale behind each adopted decision. Furthermore, it also offers an explicit mechanism to manage the different model versions that have participated during the design process. Thus, the proposed model allows the tracing of such design process and its resulting products. © 2004 Elsevier B.V. All rights reserved. |
O.A. Iribarren, J.M. Montagna, A.R. Vecchietti, B. Andrews, J.A. Asenjo, J.M. Pinto Optimal Process synthesis for the production of multiple recombinant proteins (Artículo de revista) Computer Aided Chemical Engineering, 18 (C), pp. 427-432, 2004, (cited By 2). (Resumen | Enlaces | BibTeX | Etiquetas: ) @article{Iribarren2004427, title = {Optimal Process synthesis for the production of multiple recombinant proteins}, author = { O.A. Iribarren and J.M. Montagna and A.R. Vecchietti and B. Andrews and J.A. Asenjo and J.M. Pinto}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-77955617569&partnerID=40&md5=32dbd3ea2b692551ac0e74a49b1d19b6}, doi = {10.1016/S1570-7946(04)80137-8}, year = {2004}, date = {2004-01-01}, journal = {Computer Aided Chemical Engineering}, volume = {18}, number = {C}, pages = {427-432}, abstract = {This work presents an optimization model for the synthesis of bioprocesses that contain batch and semi-continuous items that can be duplicated and operated either in or out of phase. The model minimizes the overall plant cost and is composed of sizing and cycle time constraints, multiple-choice constraints for host and stage selection as well as production targets for each product are enforced in the model. Results on a 15-stage plant that processes four products under four different hosts show that the nature of the problem greatly affects host selection, plant structure and selection of unit operations. © 2004 Elsevier B.V. All rights reserved.}, note = {cited By 2}, keywords = {}, pubstate = {published}, tppubtype = {article} } This work presents an optimization model for the synthesis of bioprocesses that contain batch and semi-continuous items that can be duplicated and operated either in or out of phase. The model minimizes the overall plant cost and is composed of sizing and cycle time constraints, multiple-choice constraints for host and stage selection as well as production targets for each product are enforced in the model. Results on a 15-stage plant that processes four products under four different hosts show that the nature of the problem greatly affects host selection, plant structure and selection of unit operations. © 2004 Elsevier B.V. All rights reserved. |