Information Systems Group

Despoina Magka

Research Student

Biography

I am a final year doctoral student and member of the Information Systems Group led by Prof. Ian Horrocks. During my DPhil, I worked on knowledge representation and reasoning formalisms modelling non-tree structures, such as complex biochemical objects. Specifically, I built a theoretical and practical logic-based framework for the classification of graph-shaped objects based on their structural properties. In the context of this framework, I researched extensions of datalog rules with existentials in the head and nonmonotonic negation in the body and their application to automatically building taxonomies of manually curated knowledge bases.

Prior to that, I completed an MSc Computer Science degree in the Department of Computer Science, University of Oxford; for my MSc project and under the supervision of Dr. Yevgeny Kazakov and Prof. Ian Horrocks I outlined polynomiality conditions for the lightweight description logic EL when extended with numerical datatypes.

For my first degree, I studied electrical and computer engineering in National Technical University of Athens. In my undergrad project and under the supervision of Dr. Giorgos Stamou, I explored methods for connecting databases and ontological knowledge under the presence of uncertainty. In particular, I developed a java tool to convert database tuples into fuzzy OWL assertions according to user-defined membership functions.

Conference Publications

@inproceedings{MaKH-IJCAI13,
title = {Computing Stable Models for Nonmonotonic Existential Rules},
  author = {Despoina Magka and Markus Kr{\"o}tzsch and Ian Horrocks },
  year = {2013},
  booktitle = {Proceedings of the 23rd International Joint
  Conference on Artificial Intelligence (IJCAI 2013)},
  location = {Beijing, China},
  publisher = {AAAI Press},
  editor    = {Francesca Rossi},
}

@inproceedings{KrMH-LPNMR13,
title = {Concrete Results on Abstract Rules},
  author = {Markus Kr{\"o}tzsch and Despoina Magka and Ian Horrocks },
  year = {2013},
  booktitle = {Proceedings of the 12th International Conference on 
  Logic Programming and Nonmonotonic Reasoning (LPNMR 2013)},
  publisher = {Springer},
}

@inproceedings{CGHKrKuMaMoWKR12,
title = {Acyclicity Conditions and their Application to Query Answering in Description Logics},
  author = {Bernardo Cuenca Grau and Ian Horrocks and Markus Kr{\"o}tzsch and Clemens Kupke and 
  			Despoina Magka and Boris Motik and Zhe Wang},
  year = {2012},
  booktitle = {Proceedings of the 13th  International Conference on Principles of Knowledge 
  			Representation and  Reasoning (KR 2012)},
  location = {Rome, Italy},
  publisher = {AAAI Press},
  editor    = {Gerhard Brewka and
               Thomas Eiter and
               Sheila A. McIlraith},
}

@inproceedings{MaMHESWC12,
  title = {Modelling Structured Domains Using Description Graphs and Logic Programming},
  author = {Despoina Magka and Boris Motik and Ian Horrocks},
  year = {2012},
  booktitle = {Proceedings of the 9th Extended Semantic Web Conference},
  volume    = {7295},
  pages     = {330-344},
  location = {Heraklion, Greece},
}

@InProceedings{MaKHIJCAR2010,
     author = {Despoina Magka and Yevgeny Kazakov and Ian Horrocks},
    title = {{T}ractable {E}xtensions of the {D}escription {L}ogic $\mathcal{EL}$ with {N}umerical {D}atatypes},
    booktitle = {Proc.\ of the Int.\ Joint Conf.\ on Automated Reasoning (IJCAR~2010)},
    editor = {J{\"u}rgen Giesl and Reiner H{\"a}hnle},
    address = {Edinburgh, UK},
    month = {July 16--19},
    year = {2010},
    publisher = {Springer},
    series = {LNAI},
    volume = {6173},
    pages = {61--75},
}

Journal Publications

@article{CHKKMMW-JAIR-2013,
title = {Acyclicity Notions for Existential Rules and Their Application to Query Answering in Ontologies},
  author = {Bernardo Cuenca Grau and Ian Horrocks and Markus Kr{\"o}tzsch and Clemens Kupke and 
  			Despoina Magka and Boris Motik and Zhe Wang},
  journal   = {Journal of Artificial Intelligence Research (JAIR)},
  volume    = {47},
   year      = {2013},
  pages     = {781-808},
}

@article {HaMaBDStevESteinJChem12,
   author    = {Janna Hastings and Despoina Magka and Colin Batchelor and Lian Duan and
                Robert Stevens and Marcus Ennis and Christoph Steinbeck},
  title     = {Structure-based classification and ontology in chemistry},
  journal   = {Journal of Cheminformatics},
  volume    = {4},
  number    = {8},
  year      = {2012},  
}

@article {MaKHJAR2011,
   author    = {Despoina Magka and Yevgeny Kazakov and Ian Horrocks},
  title     = {Tractable Extensions of the Description Logic $\{\mathcal\{EL\}\}$
               with Numerical Datatypes},
  journal   = {J. Autom. Reasoning},
  volume    = {47},
  number    = {4},
  year      = {2011},
  pages     = {427-450},
}

Workshop Publications

@inproceedings{MaMHDL12,
 title = {Nonmonotonic Existential Rules for Non-Tree-Shaped Ontological Modelling},
  author = {Despoina Magka and Markus Kr{\"o}tzsch and Ian Horrocks },
  year = {2013},
  booktitle = {Proceedings of the The 26th International Workshop on Description Logics (DL 2013)},
  location = {Ulm, Germany},
}

@inproceedings{MagkaSWAT4LS12,
  title = {Ontology-Based Classification of Molecules:
a Logic Programming Approach},
  author = {Despoina Magka},
  year = {2012},
  booktitle = {Proceedings of the 5th International Workshop on Semantic Web Applications and Tools for Life Sciences (SWAT4LS 2012)},
  note = {to appear},
}

@inproceedings{MaMHDL12,
 title = {Modelling Structured Domains Using Description Graphs and Logic Programming},
  author = {Despoina Magka and Boris Motik and Ian Horrocks},
  year = {2012},
  volume    = {846},
  booktitle = {Proceedings of the The 25th International Workshop on Description Logics (DL 2012)},
  location = {Rome, Italy},
}

@inproceedings{MaMHOWLED12,
  title = {Classifying Chemicals Using Description Graphs and Logic Programming},
  author = {Despoina Magka and Boris Motik and Ian Horrocks},
  volume = {849},
  year = {2012},
  booktitle = {Proceedings of the 9th OWL: Experiences and Directions Workshop (OWLED 2012)},
  location = {Heraklion, Greece},
}

@inproceedings{MaMHSWAT4LS11,
  title = {Chemical Knowledge Representation with Description Graphs and Logic Programming},
  author = {Despoina Magka and Boris Motik and Ian Horrocks},
  year = {2011},
  booktitle = {Proceedings of the 4th International Workshop on Semantic Web Applications 
  				and Tools for Life Sciences (SWAT4LS 2011)},
  pages     = {74-75},
  location = {London, UK},
  note = {Highlight poster},
}

@INPROCEEDINGS{MaKHDL2010,
  author = {Despoina Magka and Yevgeny Kazakov and Ian Horrocks},
  title = {{T}ractable {E}xtensions of the {D}escription {L}ogic $\mathcal{EL}$ with {N}umerical {D}atatypes},
  booktitle = {23rd International Workshop on Description Logics (DL 2010)},
  year = {2010},
  address = {Waterloo, Canada},
  month = {May 4--7},
}

Technical Reports

@TECHREPORT{MKH13tr,
title = {Stable Models for Nonmonotonic Existential Rules},
  author = {Despoina Magka and Markus Kr{\"o}tzsch and Ian Horrocks },
  institution = {University of Oxford},
  year = {2013},
}

@TECHREPORT{MagkaStudConf12,
  author = {Despoina Magka},
  institution = {Oxford University Department of Computer Science Student Conference 2012},
  title = {{Extending Logic Programming for Life Sciences Applications}},
  year = {2012},
}

@TECHREPORT{NDRTechnicalReport,
  author = {Despoina Magka and Boris Motik and Ian Horrocks},
  institution = {University of Oxford},
  title = {{M}odelling {S}tructured {D}omains {U}sing {D}escription {G}raphs and {L}ogic {P}rogramming},
  year = {2011},
}

@TECHREPORT{NDRTechnicalReport,
  author = {Despoina Magka and Yevgeny Kazakov and Ian Horrocks},
  institution = {Oxford University Computing Laboratory},
  title = {{T}ractable {E}xtensions of the {D}escription {L}ogic $\mathcal{EL}$ with {N}umerical {D}atatypes},
  year = {2010},
}

Dissertations

@mastersthesis{MagkaMScDiss,
  author = {Magka, Despoina},
  title = {{C}onsequence-{B}ased {D}atatype {R}easoning in $\mathcal{EL}$: {I}dentifying the {T}ractable {F}ragments},
  school = {Oxford University Computing Laboratory},
  year = {2009},
}

@MISC { MagkaEceProject,,
  author       = { Magka, Despoina }, 
  title        = { Database and ontology integration under uncertainty },
  howpublished = { Diploma thesis. National Technical University of Athens },
  year         = { 2008 },
}