The Experts below are selected from a list of 7368 Experts worldwide ranked by ideXlab platform
Pio A. Aguirre - One of the best experts on this subject based on the ideXlab platform.
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Novel configuration for a multistage flash-mixer desalination system
Industrial & Engineering Chemistry Research, 2003Co-Authors: Sergio Mussati, Pio A. Aguirre, Nicolás J. ScennaAbstract:In this paper a systematic procedure for the synthesis and design of multistage flash-mixer desalination processes is presented. The process configuration, geometric design, and optimal operating conditions are determined by minimizing the total annualized cost for a given water production. Different possible arrangements for the desaltor are embedded in a superstructure. The multistage flash-mixer system is rigorously modeled considering the most important aspects of the real process. The resolution procedure involves two Phases. First, a simplified model is solved in a Preprocessing Phase providing the initial values and bounds, and then from these values the rigorous model is easily solved. For the simplified model resolution in the Preprocessing Phase, there is no need for supplying and tuning external parameters for initialization. The Preprocessing Phase increases the robustness of the optimization algorithm. A new configuration of the multistage flash-mixer system system resulted. This new structur...
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Optimal Synthesis of Multicomponent Zeotropic Distillation Processes. 2. Preprocessing Phase and Rigorous Optimization of Efficient Sequences
Industrial & Engineering Chemistry Research, 2003Co-Authors: Mariana Barttfeld, Pio A. AguirreAbstract:The optimal synthesis of zeotropic efficient distillation processes is addressed in this paper. The reversible distillation sequence model (RDSM) is rigorously approximated by a sequence of adiabatic units. Alternative superstructures representations involving different energy distributions are proposed for approximating the RDSM. The efficient distillation synthesis problem is formulated as a rigorous tray-by-tray mixed-integer nonlinear programming (MINLP) problem. Discrete decisions are related to the feed and heat-exchange locations while continuous choices select the operating conditions of the process. The most suitable representation is selected by computing the entropy production of each scheme. The solution procedure includes an automatic Preprocessing Phase where reversible distillation theory is combined with mathematical programming to generate initial values and bounds for the variables involved in the rigorous MINLP problem. Convergence and robustness of the formulations are considerably improved by including this preliminary Phase. Numerical examples are reported for the separation of zeotropic mixtures to show the performance of the proposed methodology.
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Optimal Synthesis of Multicomponent Zeotropic Distillation Processes. 1. Preprocessing Phase and Rigorous Optimization for a Single Unit
Industrial & Engineering Chemistry Research, 2002Co-Authors: Mariana Barttfeld, Pio A. AguirreAbstract:Separations performed by distillation involve large operation costs due to either large heat loads or large amounts of solvent used in azeotropic mixtures. Thermodynamic aspects helpfully lead the process synthesis to energetically efficient designs. The reversible distillation sequence model (RDSM) is employed in this work as a theoretical and ideal thermodynamic model. The aim of the paper is to present an automatic methodology for the synthesis of simple distillation columns that approximate reversible conditions. A Preprocessing Phase is considered where proper values to initialize and bound the variables involved in the rigorous model are calculated by successively solving auxiliary optimization models. In all cases studied, the solutions obtained are very similar to those in the so-called reversible separation. This fact is used as a test criterion for global optimality of the solutions.
Mariana Barttfeld - One of the best experts on this subject based on the ideXlab platform.
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Optimal Synthesis of Multicomponent Zeotropic Distillation Processes. 2. Preprocessing Phase and Rigorous Optimization of Efficient Sequences
Industrial & Engineering Chemistry Research, 2003Co-Authors: Mariana Barttfeld, Pio A. AguirreAbstract:The optimal synthesis of zeotropic efficient distillation processes is addressed in this paper. The reversible distillation sequence model (RDSM) is rigorously approximated by a sequence of adiabatic units. Alternative superstructures representations involving different energy distributions are proposed for approximating the RDSM. The efficient distillation synthesis problem is formulated as a rigorous tray-by-tray mixed-integer nonlinear programming (MINLP) problem. Discrete decisions are related to the feed and heat-exchange locations while continuous choices select the operating conditions of the process. The most suitable representation is selected by computing the entropy production of each scheme. The solution procedure includes an automatic Preprocessing Phase where reversible distillation theory is combined with mathematical programming to generate initial values and bounds for the variables involved in the rigorous MINLP problem. Convergence and robustness of the formulations are considerably improved by including this preliminary Phase. Numerical examples are reported for the separation of zeotropic mixtures to show the performance of the proposed methodology.
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Optimal Synthesis of Multicomponent Zeotropic Distillation Processes. 1. Preprocessing Phase and Rigorous Optimization for a Single Unit
Industrial & Engineering Chemistry Research, 2002Co-Authors: Mariana Barttfeld, Pio A. AguirreAbstract:Separations performed by distillation involve large operation costs due to either large heat loads or large amounts of solvent used in azeotropic mixtures. Thermodynamic aspects helpfully lead the process synthesis to energetically efficient designs. The reversible distillation sequence model (RDSM) is employed in this work as a theoretical and ideal thermodynamic model. The aim of the paper is to present an automatic methodology for the synthesis of simple distillation columns that approximate reversible conditions. A Preprocessing Phase is considered where proper values to initialize and bound the variables involved in the rigorous model are calculated by successively solving auxiliary optimization models. In all cases studied, the solutions obtained are very similar to those in the so-called reversible separation. This fact is used as a test criterion for global optimality of the solutions.
Isabel Harb Manssour - One of the best experts on this subject based on the ideXlab platform.
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Visualization in the Preprocessing Phase: Getting insights from enterprise professionals:
Information Visualization, 2020Co-Authors: Alessandra Maciel Paz Milani, Fernando V. Paulovich, Isabel Harb ManssourAbstract:The current information age has increasingly required organizations to become data-driven. However, analyzing and managing raw data is still a challenging part of the data mining process. Even thou...
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Visualization in the Preprocessing Phase: an interview study with enterprise professionals.
arXiv: Human-Computer Interaction, 2019Co-Authors: Alessandra Maciel Paz Milani, Fernando V. Paulovich, Isabel Harb ManssourAbstract:The current information age has increasingly required organizations to become data-driven. However, analyzing and managing raw data is still a challenging part of the data mining process. Even though we can find interview studies proposing design implications or recommendations for future visualization solutions in the data mining scope, they cover the entire workflow and do not fully focus on the challenges during the Preprocessing Phase and on how visualization can support it. Moreover, they do not organize a final list of insights consolidating the findings of other related studies. Hence, to better understand the current practice of enterprise professionals in data mining workflows, in particular during the Preprocessing Phase, and how visualization supports this process, we conducted semi-structured interviews with thirteen data analysts. The discussion about the challenges and opportunities based on the responses of the interviewees resulted in a list of ten insights. This list was compared with the closest related works, improving the reliability of our findings and providing background, as a consolidated set of requirements, for future visualization research papers applied to visual data exploration in data mining. Furthermore, we provide greater details on the profile of the data analysts, the main challenges they face, and the opportunities that arise while they are engaged in data mining projects in diverse organizational areas.
Alessandra Maciel Paz Milani - One of the best experts on this subject based on the ideXlab platform.
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Visualization in the Preprocessing Phase: Getting insights from enterprise professionals:
Information Visualization, 2020Co-Authors: Alessandra Maciel Paz Milani, Fernando V. Paulovich, Isabel Harb ManssourAbstract:The current information age has increasingly required organizations to become data-driven. However, analyzing and managing raw data is still a challenging part of the data mining process. Even thou...
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Visualization in the Preprocessing Phase: an interview study with enterprise professionals.
arXiv: Human-Computer Interaction, 2019Co-Authors: Alessandra Maciel Paz Milani, Fernando V. Paulovich, Isabel Harb ManssourAbstract:The current information age has increasingly required organizations to become data-driven. However, analyzing and managing raw data is still a challenging part of the data mining process. Even though we can find interview studies proposing design implications or recommendations for future visualization solutions in the data mining scope, they cover the entire workflow and do not fully focus on the challenges during the Preprocessing Phase and on how visualization can support it. Moreover, they do not organize a final list of insights consolidating the findings of other related studies. Hence, to better understand the current practice of enterprise professionals in data mining workflows, in particular during the Preprocessing Phase, and how visualization supports this process, we conducted semi-structured interviews with thirteen data analysts. The discussion about the challenges and opportunities based on the responses of the interviewees resulted in a list of ten insights. This list was compared with the closest related works, improving the reliability of our findings and providing background, as a consolidated set of requirements, for future visualization research papers applied to visual data exploration in data mining. Furthermore, we provide greater details on the profile of the data analysts, the main challenges they face, and the opportunities that arise while they are engaged in data mining projects in diverse organizational areas.
S. Schmitz - One of the best experts on this subject based on the ideXlab platform.
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ICDM - Findings from a practical project concerning Web usage mining
Third IEEE International Conference on Data Mining, 1Co-Authors: Frank Dellmann, H. Wulff, S. SchmitzAbstract:In a practical project a statistical analysis of the Web log files of the domain www.volkswagen.de was carried out by using the CRISP-DM procedure. For the Preprocessing Phase, more profound findings could be gained than are usually described in many studies. Since the aim was to deduce significant statements while measuring the effect, tests of significance for e-metrics were used in addition to the commonly described procedure.