Pablo E. Roman CMM's Homepage

Current post: Assistant Professor at DIINF
Past post: Postdoctoral Researcher (Fondecyt Fellow) at CMM
Description: With the operation of the ALMA radio-interferometric observatory, a large amount of preprocessing will be required. The ALMA instrument observatory has already begun operations with reduced capabilities, and will reach completion by 2013, recording a Tb per day in Fourier space radio signals over 60 antennas, in a 16 km wide surface. ALMA is the largest steerable telescope on earth. It is the result of a joint Asian-American-European effort with no precedent in history. In 2011, the first stage of the project will deliver data from today's installed commissioned capabilities with about 20 antennas. These data will require substantial post-processing for the construction of sky images. The ALMA data sparsely sample the Fourier transform of the sky images; substantial statistical analysis is required to invert the ALMA data into an image of the sky. The difficulties involved in this post-processing include the need for algorithmic research in image synthesis, as well as practical aspects of data handling in the C language. A Bayesian image synthesis pipeline would extract the full potential of the ALMA data. This proposal is part of the ALMA-CONICYT Project ''Bayesian image synthesis for ALMA and VLTI.'' directed by Dr. Simon Cassasus of the Department of Astronomy in collaboration with the Center for Mathematical Modeling (CMM) of the University of Chile.

Full Name: Pablo Enrique Román Asenjo
Affiliation: Center for Mathematical Modeling
University of Chile
Institute of Complex Engineering Systems
University of Chile
E-mail: proman AT ing.uchile.cl
Citations RG Score Scopus Author ORCID DBLP Mendeley


Education


1994 Bachelor of Science Physics University of Chile
1999 Bachelor of Science Computer Science and Engineering University of Chile
1999 Civil Engineering Computer Science University of Chile
2011 Doctor Engineering Systems University of Chile


Dissertation Adviser (Ph.D): Juan D. Velásquez (mailto:jvelasqu@dii.uchile.cljvelasqu@dii.uchile.cl)
Dissertation Title: ``Web User Behavior Analysis.''
http://www.cmm.uchile.cl/~proman/Thesis.Pablo.E.Roman.pdf
Civil Engineering Degree Adviser: Eric Goles Chacc
Engineering Dissertation Title:``Granular system simulation using cellular automata.''

Current affiliation: Postdoctoral assistant research, Laboratory of astroinformatics, Center for Mathematical Modeling (CMM), Mathematical Engineering Department, University of Chile.

Major research interest
Research keywords (Alphabetic): Astro-informatics, Data mining, Discrete choice analysis, Discrete optimization, High performance computing, Human behavior models, Machine learning, Massive data, Natural language processing, Neurocomputing, Numerical analysis of partial differential equation, Numerical algorithm, Physics: Quantum and diffusion system, Social Network, Stochastic models, Stochastic optimization, Web usage mining.

In order to clarify my research directions, I first describe my area of expertise. I have a broad-spectrum background that ranges from fundamental physics science (B.S.Phy.), computer science (B.C.S, C. Eng.), complex system engineering (Ph.D.), and industrial engineering. I strongly believe that fruitful results emerge from multidisciplinary research interaction. With such a premise my research interests include various subjects, as follows. Modeling human behavior has been a concern for several disciplines (e.g. economics). My thesis develops a description of dynamic decision making for web users using basic first principles of neuroscience. I consider as a future research goal to adapt such a model to other human activities. Data preprocessing has always been an issue in science. For my thesis work it was necessary to ensure the processing of massive amounts of data from web logs. The most computationally complex part of this process is the reconstruction of individual activities. The proposed solution was an integer programming model, which solves in polynomial time (network flow problem) with much better accuracy than previous processing models. For my thesis work, I also had to analyze numerically higher dimensional partial differential diffusion equations. The method proposed was based on symbolic processing for the particular boundary condition. Further generalization of this numerical method has interest and applications in others areas.

A polynomial solution for the unconstrained Fokker-Plank problem representing neural activity of a two-choice desicion-making model.



Publications list

ISI Indexed Journal Paper
  1. (2015) H. Canovas, M. R. Schreiber, C. Caceres, F. Menard, C. Pinte, G. S. Mathews, L. Cieza, S. Casassus, A. Hales, J. P. Williams, Pablo E. Román, and A. Hardy, Gas inside the 97 au cavity around the transition disk Sz 91, The Astrophysical Journal (ApJ), 805 (1), pp21, http://dx.doi.org/10.1088/0004-637X/805/1/21
  2. (2015) S. Perez, S. Casassus, F. Menard, Pablo E. Román, G. van der Plas, L. Cieza, C. Pinte, V. Christiaens, and A. S. Hales, CO Gas inside the protoplanetary disk structure from ALMA, The Astrophysical Journal (ApJ) http://dx.doi.org/10.1088/0004-637X/798/2/85
  3. (2013) Pablo E. Román and Juan D. Velásquez, A neurology-inspired model of web usage, Neurocomputing, Available online 29 October 2013, ISSN 0925-2312, http://dx.doi.org/10.1016/j.neucom.2013.10.012
  4. (2013) Tomás Arce, Pablo E. Román, Juan Velásquez, Victor Parada, Identifying web sessions with simulated annealing, Expert Systems with Applications, http://dx.doi.org/10.1016/j.eswa.2013.08.056
  5. (2013) Simon Casassus, Gerrit van der Plas, Sebastian Perez, M William R. F. Dent, Ed Fomalont, Janis Hagelberg, Antonio Hales, Andrés Jordán, Dimitri Mawet, Francois Ménard, Al Wootten, David Wilner, A. Meredith Hughes, Matthias R. Schreiber, Julien H. Girard, Barbara Ercolano, Hector Canovas, Pablo E. Román, Vachail Salinas. ``Flows of gas through a protoplanetary gap'', NATURE, Number 493, pp. 191-194 (10 January 2013), http://dx.doi.org/10.1038/nature11769
  6. (2012) Pablo Loyola, Pablo E. Román, and Juan D. Velásquez, ``Predicting Web User Behavior Using Learning-Based Ant Colony Optimization,'' Journal of Engineering Applications of Artificial Intelligence, Vol. 25, Number 5, Pag. 889-897,2012. http://dx.doi.org/10.1016/j.engappai.2011.10.008
  7. (2013) Pablo E. Román, Robert F. Dell, and Juan D. Velásquez, ``Optimization models for construction of web user sessions,", Vol. 18, Num. 1, pp. 43-61 ,Journal Intelligent Data Analysis (IDA), ACCEPTED, IOS Press. ISSN:1088-467X. http://dx.doi.org/10.3233/IDA-130627
Book Chapters
  1. (2013) Pablo E. Román, and Juan D. Velásquez, ``Cognitive science in the study of web usage,'' Chapter 4 in ``Advances Techniques in Web Intelligence - 2,'' Studies in Computational Intelligence, V. Palade, J.D. Velásquez, and L. Jain Eds.; Springer Verlag, 42 pages. 2013, Volume 452/2013, 35-73, doi: 10.1007/978-3-642-33326-2_3
  2. (2013) Pablo E. Román, and Juan D. Velásquez, Vasile Palade, and Lakhmi C. Jain ``New Trends in Web User Behaviour Analysis,'' Chapter 1 in ``Advances Techniques in Web Intelligence - 2,'' Studies in Computational Intelligence, V. Palade, J.D. Velásquez, and L. Jain Eds.; Springer Verlag, 10 pages. , 2013, Volume 452/2013, 1-10, doi: 10.1007/978-3-642-33326-2_1
  3. (2010) Pablo E. Román, Robert F. Dell and Juan D. Velásquez, ``Advanced Technique in Web Data Pre-Processing and Cleaning,'' Chapter in the book ``Advances Techniques in Web Intelligence-1,'' J.D. Velásquez and L. Jain Ed., Springer Verlag, Volume 311, 2010, pp 19- 48. doi:10.1007/978-3-642-14461-5_2
  4. (2010) Pablo E. Román, G. L'Huillier and Juan D. Velásquez; "Web Usage Mining" Chapter in book "Advances in Techniques in Web Intelligence-1," J.D. Velásquez and L. Jain Ed., Springer Verlag, Volume 311, 2010, pp 143- 165. doi:10.1007/978-3-642-14461-5_6
Conference invited lecture
  1. (2013) Pablo E. Román ``Current Trends in Radio Image Synthesis,'' Invited Lecture. International Meeting of AstroStatistics in Valparaiso (IMAV) 2013. http://imav2013.cimfav.cl/
  2. (2009) Pablo E. Román and Juan D. Velásquez, ``A Dynamic Stochastic Model Applied to the Analysis of the Web User Behaviour,'' Invited Lecture. ADVANCES IN INTELLIGENT WEB MASTERING - 2, Advances in Intelligent and Soft Computing, 2010, Volume 67/2010, pp. 31- 39, DOI:10.1007/978-3-642-10687-3_3
DBLP's indexed Conference proceedings
  1. (2014) Pablo E. Román, T. Asahi, S. Casassus, Hermite-Gaussian functions for image synthesis, APSIPA IEEE conference 2014.
    http://dx.doi.org/10.1109/APSIPA.2014.7041608
  2. (2013) Pablo E. Román, and Juan D. Velásquez. ``A Web Browsing Cognitive Model''. Knowledge Engineering, Machine Learning and Lattice Computing with Applications series, LNCS 7828, KES 2012 Revised Selected Papers, pag. 31-40 - Springer Berlin Heidelberg. ISBN 978-3-642-37342-8. DOI:10.1007/978-3-642-37343-5_4
  3. (2012) Pablo E. Román, Miguel E. Gutiérrez, and Sebastián A. Rios. ``A model for content generation in On-line social network''. Frontiers in Artificial Intelligence and Applications (FAIA) series, Vol. 243, pag. 756-765 - IOS Press. doi:10.3233/978-1-61499-105-2-756
  4. (2012) Pablo E. Román, and Juan D. Velásquez. ``A cognitive model of the web user''. Frontiers in Artificial Intelligence and Applications (FAIA) series, Vol. 243, pag. 605-614 - IOS Press. doi:10.3233/978-1-61499-105-2-605
  5. (2011) Loyola, P., Pablo E. Román, Velásquez, J.D.; , "Clustering-Based Learning Approach for Ant Colony Optimization Model to Simulate Web User Behavior," Web Intelligence and Intelligent Agent Technology (WI-IAT), 2011 IEEE/WIC/ACM International Conference on , vol.1, pp.457-464, 22-27 Aug. 2011, doi: 10.1109/WI-IAT.2011.116
  6. (2010) Pablo E. Román and Juan D. Velásquez, , ``Stochastic Simulation of Web Users,'' Web Intelligence and Intelligent Agent Technology (WI-IAT), 2010 IEEE/WIC/ACM International Conference on , vol.1, no., pp.30-33, Aug. 31 2010-Sept. 3 2010, doi: 10.1109/WI-IAT.2010.60
  7. (2009) (ISI indexed conference) Robert F. Dell, Pablo E. Román, and Juan D. Velásquez, ``Web User Session Reconstruction with Back Button Browsing,'' Lecture Notes in Computer Science, 2009, Volume 5711/2009, pp. 326- 332, DOI:10.1007/978-3-642-04595-0_40
  8. (2008) Robert F. Dell, Pablo E. Román and Juan D. Velásquez, ``Web User Session Reconstruction Using Integer Programming,'' Web Intelligence and Intelligent Agent Technology, 2008. WI-IAT '08. IEEE/WIC/ACM International Conference, vol.1, pp.385-388, 9-12 Dec. 2008. doi:10.1109/WIIAT.2008.181.
International technical paper
  1. (2009) Pablo E. Román and Juan D. Velásquez, ``Analysis of the Web User Behavior with a Psychologically-Based Diffusion Model. AAAI Fall Symposium Series, North America, oct. 2009. Available at:
    http://www.aaai.org/ocs/index.php/FSS/FSS09/paper/view/861
  2. (2009) Robert F. Dell, Pablo E. Román, and Juan D. Velásquez, ``Fast Combinatorial Algorithm for Web User Session Reconstruction,'' p. 2; 2009; Procs. Of the 24th IFIP TC7 Conference, Buenos Aires, Argentina. Page 91-92. With oral presentation by Pablo E. Román.
National Conferences and journals
  1. (2012) Sebastián Perez, Pablo E. Román, Simon Casassus. ``ALMA estimate of the gap depth in the HD142527 protoplanetary disk''. The first year of ALMA Science. Puerto Varas, Chile, Dec. 12-15.
  2. (2012) Pablo E. Román. ``El problema de síntesis de fourier en radio - astronomía y su resolución mediante métodos variacionales''. Journal of the Chilean Institute of Operation Research (JCIOR). Vol. 2, Num. 1, ISSN: 718-9605.
  3. (2012) Miguel E. Gutiérrez, Pablo E. Román, and Sebastián A. Rios. ``Toward a simulation of online social network dynamics''. Jornadas Chilena de Computacion (JCC-2012), Valparaiso, Chile.
  4. (2010) Pablo E. Román and Juan D. Velásquez, ``The Time Course of the Web User,'' Procs. Of the Second Workshop on Time Use Observatory (TUO2), Chillan, Chile. With oral presentation by Pablo E. Román.
  5. (2010) Pablo E. Román and Juan D. Velásquez, ``Artificial Web User Simulation and Web Usage Mining,'' 2010, Procs. Of the First Workshop in Business Analytics and Optimization (BAO 2010), Santiago, Chile. With oral presentation by Pablo E. Román.
  6. (2010) E. Andaur, S. Rios, Pablo E. Román and Juan D. Velásquez, ``Best Web Site Structure for Users Based on a Genetic Algorithm Approach,'' 2010, Procs. Of the First Workshop in Business Analytics and Optimization (BAO), Santiago, Chile. Eng. Degree of E. Andaur with Co-Guidance by Pablo E. Román.
  7. (2010) Pablo Loyola, Pablo E. Román, and Juan D. Velásquez, ``Ant Colony Surfer: Discovering the Distribution of Text Preferences from Web Usage,'' In Procs. Of the First Workshop in Business Analytics and Optimization (BAO), Santiago, Chile. Eng. Degree of P. Loyola with Co-Guidance by Pablo E. Román.
  8. (2009) Robert F. Dell, Pablo E. Román, and Juan D. Velásquez; ``Un método de optimización lineal entera para el análisis de sesiones de usuarios web,'' Revista de Ingenieria de Sistemas, 23(1), pp. 109-124. http://www.dii.uchile.cl/~ris/RISXXIII/Roman109.pdf
  9. (1992) Pablo E. Román, Ivan Piñeiro and Víctor Fuenzalida, ``Barium thin film incorporation at titanium substrate,'' p. 11, Proceedings of VIII Chilean Physics workshop, Num.127, Vol. 1, SOCHIFI-Scientia, Valparaiso, Chile.
Thesis
  1. (2011) Pablo E. Román, ``Web User Behavior Analysis,'' Thesis submitted in partial fulfillment for the degree of Doctor of Philosophy in Engineering Systems. University of Chile. http://www.cybertesis.uchile.cl/tesis/uchile/2011/cf-roman_pa/html/index-frames.html
  2. (1999) Pablo E. Román, ``Granular system simulation using cellular automata,'' document submitted in partial fulfillment for the degree of Computer Engineer and Bachelor in Computer Science, Advisor Eric Goles, Pablo Dartnel, and José M. Piquer. http://catalogo.uchile.cl/uhtbin/cgisirsi/?ps=Jy5BquDsvE/SISIB/274720034/8/756936/Simulaci%F3n+de+sistemas+granulares+mediante+aut%F3matas+celulares+^2F
Others international presentation
  1. (2009) (SYMPOSIUM PAPER) Robert F. Dell, Pablo E. Román and Juan D. Velásquez, ``Optimization Models for Construction and Analysis of Web User Sessions,'' p. 1; 2009; Procs. 11th Informs Computing Society Conference, Charleston, South Carolina, USA.
  2. (2008) (SYMPOSIUM PAPER) Robert F. Dell, Pablo E. Román and Juan D. Velásquez, ``Identifying Web User Session using an Integer programming Approach,'' p. 3, Procs. Of The XIV Latin Ibero-American Congress on Operations Research (CLAIO 2008), Cartagena, Colombia. With oral presentation by Pablo E. Román.
  3. (2008) (SYMPOSIUM PAPER) Pablo E. Román, and Juan D. Velásquez, ``Markov Chain for modelling the Web User Behaviour,'' p. 3; Procs. Of The XIV Latin Ibero-American Congress on Operations Research (CLAIO 2008), Cartagena, Colombia. With oral presentation by Pablo E. Román.
  4. (2006) (SYMPOSIUM PAPER) Pablo E. Román and Juan D. Velásquez, ``Improving a Web Site using Keywords,'' p. 6, Procs. XIII Congreso Latino-Iberoamericano de Investigacion Operativa CLAIO 2006, Montevideo, Uruguay. With oral presentation by Pablo E. Román.

Grants and Awards

(2014) Postdoctoral Fondecyt Fellow.
Center of Mathematical Modelling, Universidad de Chile, Chile.
(2010) Doctoral full support scholarship from the Institute of Complex Engineering System.
(http://www.sistemasdeingenieria.cl), Chile. March-Dec.
(2008-2009) Doctoral full support scholarship from the Chilean government. Conicyt
(www.conicyt.cl), Chile.
(2007) Doctoral support scholarship, Millenium Institute Engineering Complex Systems.
(2006) Faculty full support doctoral scholarship. University of Chile.


Thesis and Engineering Guidance

(2012) ``Profesor Co-Guia'' (co-advisor) Miguel E. Gutiérrez, ``Development, Implementation and Evaluation of a Topics Diffusion Model through Social Networks'', U. of Chile.
(2011) ``Supporting member,'' Tomas Arce, Informatic Engineering disertation. ``Estudio del problema de sesionización, utilizando simulated annealing y algoritmos genéticos,'' USACH.
(2011) ``Profesor Co-Guia,'' (co-advisor) Pablo S. Loyola, Industrial Engineering disertation. ``Análisis del comportamiento del usuario web a partir de la simulación de su navegación usando optimización de colonias de hormigas,'' U. of Chile.
(2010) ``Profesor Co-Guia,'' (co-advisor) Evelyn Andaur, Industrial Engineering disertation. ``Análisis del Comportamiento del Usuario en la Web para Optimizar la Estructura de Navegación de un Sitio Usando Algoritmos Genéticos,'' U. of Chile.
(2010) ``Profesor Integrante,'' (member of the comission) Pablo Acuña, Thesis Master MGO. ``Adaptación de una Herramienta Crm Open Source para Mypymes del Sector Financiero,'' U. of Chile.
(2010) ``Profesor Integrante,'' (member of the comission) Rodrigo Zarate Rodrígez, Thesis Master MGO. ``Diseño y desarrollo de un algoritmo de detección de patrones de copia en documentos digitales,'' U. of Chile.
(2010) ``Profesor Integrante,'' (member of the comission) Victor Rebolledo, Thesis Master MGO. ``Plataforma para la Extracción y Almacenamiento del Conocimiento Extraído de los Web Data,'' U. of Chile.
(2009) ``Profesor Integrante,'' (member of the comission) Robert Cercos, Industrial Engineering dissertation. ``Diseño y Construcción de un Web Warehouse para Almacenar Información Extraída a Partir de Datos Originados en la Web'', U. of Chile.
(2008) ``Profesor Integrante,'' (member of the comission) Lucía Hernandez, Thesis Master MGO. ``Diseño y Construccion de un Data Mart para la Mantención de Indicadores de Sostenibilidad de la Industria del Salmón,'' U. of Chile.


Journal and Committee Reviews

(2011-2012) Member of the Program Committee of BICA AAAI conference 2011,2012,
http://bicasociety.org/
(2011-2012) Reviewer for Revista del Instituto Chileno de Investigación Operativa (ICHIO) 2011-2012.
(2010-2011) Reviewer for Journal of Engineering Applications of Artificial Intelligence, Elsevier.
(2010-2011) Reviewer for Journal of Mathematical and Computer Modeling, Elsevier.