Biography

Detailed biography is available here.

Professional Activity

Formal languages theory and applications, formal grammars and other languages specification formalisms, parallel and asynchronous computations.

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Academic Advising

Projects

Publications

  • Rustam Azimov, Semyon Grigorev

    Graph data model is widely used in many areas, for example, bioinformatics, graph databases, RDF. One of the most common graph queries are navigational queries. The result of query evaluation are implicit relations between nodes of the graph, i.e. paths in the graph. A natural way to specify these relations is by specifying paths using formal grammars over edge labels. This type of queries is usually evaluated using the relational query semantics. There is a number of algorithms for query evaluation which use such semantics but they have computational problems with big data. One of the most common technique for efficient big data processing is GPGPU, but these algorithms do not allow to use this technique effectively. In this paper we propose a graph parsing algorithm for query evaluation which use relational query semantics and context-free grammars, and is based on matrix operations which allows to speed up computations by means of GPGPU.

    arXiv, July 2017
  • Semyon Grigorev, Anastasiya Ragozina

    Graph data model and graph databases are very popular in various areas such as bioinformatics, semantic web, and social networks. One specific problem in the area is a path querying with constraints formulated in terms of formal grammars. The query in this approach is written as grammar, and paths querying is graph parsing with respect to given grammar. There are several solutions to it, but how to provide structural representation of query result which is practical for answer processing and debugging is still an open problem. In this paper we propose a graph parsing technique which allows one to build such representation with respect to given grammar in polynomial time and space for arbitrary context-free grammar and graph. Proposed algorithm is based on generalized LL parsing algorithm, while previous solutions are based mostly on CYK or Earley algorithms, which reduces time complexity in some cases.

    arXiv, December 2016
  • Marina Polubelova, Sergey Bozhko, Semyon Grigorev

    There are numerous toolchains designed for certified programming, but F* is the only language that support both general-purpose programming and semi-automated proving. We work on the application of this technique to a grammarware research and development project YaccConstructor. We present a work in progress verified implementation of transformation of Context-free grammar to Chomsky normal form, that is making progress toward the certification of the entire project. Among other features, F* system allows to extract code in F# or OCaml languages from a program written in F*. YaccConstructor project is mostly written in F#, so this feature of F* is of particular importance because it allows to maintain compatibility between certified modules and those existing in the project which are not certified yet.

    Proceedings of the Institute for System Programming, August 2016
  • Ekaterina Verbitskaia , Semyon Grigorev, Dmitry Avdyukhin
    Perspectives of System Informatics, June 2016
  • Marina Polubelova, Semyon Grigorev
    Systems and Means of Informatics, 2016
  • Ragozina Anastasiya, Grigorev Semyon
    Systems and Means of Informatics, 2015
  • Ekaterina Verbitskaia, Semyon Grigorev and Dmitry Avdyukhin
    Proceedings of 10th International Andrei Ershov Memorial Conference on Perspectives of System Informatics, 2015
  • Marat Khabibullin, Andrei Ivanov, Semyon Grigorev
    Proceedings of the 11th Central & Eastern European Software Engineering Conference in Russia, 2015
  • Semen Grigorev, Ekaterina Verbitskaia, Andrei Ivanov, Marina Polubelova, and Ekaterina Mavchun
    Proceedings of the 10th Central and Eastern European Software Engineering Conference in Russia 2014, 2014
  • Semen Grigorev and Iakov Kirilenko
    Proceedings of the 9th Central & Eastern European Software Engineering Conference in Russia, 2013