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FACULTY OF MATHEMATICS AND COMPUTER SCIENCE

Radu Buzatu


First Name
Radu
Last Name
Buzatu
Scientific degree
doctor
Academic title/position
lecturer
Department
Mathematics Department
Education

 

Moldova State University, Faculty of Mathematics and Computer Science

2013 – 2017

PhD in Mathematical Sciences. Thesis: “Covers of Undirected Graphs by Convex Sets”. Operational Research and Cybernetics. Advisor: Sergiu Cataranciuc, Dr. habil., Professor

2011 – 2013

Master in Applied Mathematics. Statistical Analysis of Economic Processes

2008 – 2011

Bachelor in Computer Science. Information Management

 

Professional experience

2013 – present

Researcher, Moldova State University, Faculty of Mathematics and Computer Science,

Mathematical Modeling and Optimization Laboratory,

Results:

  • Proved that the problem of deciding whether a graph can be covered (partitioned) by a given number of convex sets is NP-complete;
  • Identified a series of graphs classes for which there exists a cover (partition) by a given number of convex sets;
  • Established conditions for the existence of a graph with the given minimum number of convex sets and minimum (maximum) number of nontrivial convex sets, which cover or partition a graph. Proved that it is NP-hard to determine these invariants for a graph;
  • Proposed a polynomial algorithm that determines whether a tree can be partitioned into a given number of nontrivial convex sets, and showed that it can be verified in polynomial time whether a graph can be covered by an arbitrary number of nontrivial convex sets;
  • Developed a library of algorithms by using C# language for decision whether a graph can be covered (partitioned) by convex sets, which may be applied to facility location problem;
  • Developed a binary linear programming model for optimizing administrative-territorial structure of the state that takes into consideration population, economic development, ethnic structure, territorial and road connectivity;
  • Developed an information system by using MATLAB for simulations of optimal scenarios of administrative-territorial organization in real time;
  • Developed a technique based on mixed integer programming for detecting gerrymandering in parallel voting systems.
Didactic activity

2017 – present

Moldova State University, Faculty of Mathematics and Computer Science,

Department of Mathematics,

Courses:

  • Discrete Mathematics;
  • Combinatorial Optimization;
  • Linear programming;
  • Graph Theory;
  • Mathematical Software;
  • Information and Communication Technology.
Scientific activity

List of scientific papers and books

  1. Buzatu R., Cataranciuc S., Convex graph covers. Computer Science Journal of Moldova (ISSN 1561-4042), Vol. 23, Nr.3(69), 2015, p.251-269;
  2. Buzatu R., Covers of graphs by two convex sets. Studia Universitatis Babeș-Bolyai, Informatica, Vol. LXI, Nr.1, 2016, p.5-22;
  3. Buzatu R., Minimum convex cover of special nonoriented graphs. Studia Universitatis Moldaviae, Exact and Economic Science (ISSN:1857-2073), Nr. 2(92), 2016, p.46-54;
  4. Buzatu R., Cataranciuc S., Nontrivial convex covers of trees. Bulletin of Academy of Sciences of Republic of Moldova, Mathematics (ISSN:1024-7696), Nr.3(82), 2016, p.72-81;
  5. Buzatu R., Cataranciuc S., On nontrivial covers and partitions of graphs by convex sets. Computer Science Journal of Moldova (ISSN:1561-4042), Vol.26, Nr.1(76), 2018, p.3-14;
  6. Buzatu R., Rabei C., Roșcovan M., A mathematical model for optimization of administrative-territorial organization of the Republic of Moldova, Studia Universitatis Moldaviae, Exact and Economic Science (ISSN:1857-2073), Nr.2(112), 2018, p.164-170.
  7. Cataranciuc S., Buzatu R., Tkacenko A., Hâncu B., Novac L., Pațiuc V., Rîbacova G., Cucu I. Disctrete structures and optimization problems. Monograph. Chapter II. Chișinău, (ISBN 978-9975-149-44-0), 2019, 454 p;
  8. Buzatu R., Binary linear programming approach for graph convex covering problems.  Bulletin of Academy of Sciences of Republic of Moldova, Mathematics (ISSN:1024-7696), Nr.3(91), 2019, p.54-59;
  9. Buzatu R., On the computational complexity of optimization convex covering problems of graphs. Computer Science Journal of Moldova (ISSN:1561-4042), Vol.28, Nr.2(83), 2020, p.187-200;
  10. Mandric I., Roșca I., Buzatu R., Gerrymandering and fair districting in parallel voting systems. arXiv:2002.06849v1, 2020, 23 p.
  11. Buzatu R., Maximum nontrivial convex cover number of join and corona of graphs.  Bulletin of Academy of Sciences of Republic of Moldova, Mathematics, in press.

List of scientific conferences

  1. Buzatu R., Poștaru A., Genetic algorithms. Some applications. Scientific Annals of the Moldova State University, Natural and Exact Sciences, 2011, Chișinău, Moldova, p. 124 - 127;
  2. Buzatu R., Iurco D., Knowledge interchange between semantic technologies in building of intelligent interfaces. Proceedings of the International Conference “Mathematics & Information Technologies: Research and Education” (MITRE – 2013), August 18 - 22, 2013, Chișinău, Moldova, p. 107;
  3. Andrieș I., Buzatu R., Tridimentional spectral color model as an one to one transformation from rgb color space. Proceedings of the International Conference “Mathematics & Information Technologies: Research and Education” (MITRE – 2013), August 18 - 22, 2013, Chișinău, Moldova, p. 102;
  4. Buzatu R., Convex covers of undirected graph. Proceedings of the 22nd Conference on Applied and Industrial Mathematics, (CAIM-2014), September 18 - 21, 2014, Bacău, Romania, p. 47 - 48;
  5. Buzatu R., NP-completeness of graph convex cover problems. Proceedings of the International Conference “Mathematics & Information Technologies: Research and Education” (MITRE – 2015), July 2 - 5, 2015, Chișinău, Moldova, p. 13;
  6. Andrieș I., Buzatu R., Ordering colors of the hvs color model in an one-dimentional physical spectrum. Proceedings of the International Conference “Mathematics & Information Technologies: Research and Education” (MITRE – 2015), July 2 - 5, 2015, Chișinău, Moldova, p. 89;
  7. Buzatu R., Nontrivial convex 2-covers of simple connected graphs. Proceedings of the 23rd Conference on Applied and Industrial Mathematics (CAIM-2015), September 17 - 20, 2015, Suceava, Romania, p. 36-37;
  8. Buzatu R., Convex 2-covers of nonoriented graphs. Proceedings of the International Conference „Integration through Research and Innovation”, Moldova State University,  November 10 - 11, 2015, Chișinău, Moldova, p. 177 - 180;
  9. Buzatu R., Cataranciuc S., Cover of a nonoriented graph by nontrivial convex sets. Proceedings of the 5th International Conference “Mathematical Modeling, Optimization and Information Technologies”, Academy of transport, informatics and communication, March 22 - 25, 2016, Chișinău, Moldova, p.64 - 71;
  10. Buzatu R., Cataranciuc S., Minimum convex covers of some graph operations. Proceedings of the Annual Conference of the Romanian Mathematical Society, May 19 -22, 2016, Baia Mare, Romania, p. 18 - 19;
  11. Buzatu R., Nontrivial convex partition of a tree. Proceedings of the International Conference “Mathematics & Information Technologies: Research and Education” (MITRE – 2016), June 23 - 26, 2016, Chișinău, Moldova, p. 12 - 13;
  12. Buzatu R., Nontrivial convex cover of a tree. Proceedings of the 24th Conference on Applied and Industrial Mathematics (CAIM-2016), September 15 - 18, 2016, Craiova, Romania, p. 82;
  13. Buzatu R., Maximum nontrivial convex cover of a tree. Proceedings of the Fourth Conference of Mathematical Society of the Republic of Moldova, June 28 - July 2, 2017, Chișinău, Moldova, p. 365 - 368;
  14. Buzatu R., Algorithms for determining nontrivial convex covers of graphs. Proceedings of the 25th Conference on Applied and Industrial Mathematics (CAIM-2017), September 14 - 17, 2017, Iași, Romania, p. 49 - 50;
  15. Buzatu R., Partitioning a graph into convex sets. Some applications.  Proceedings of the Annual Conference of the Romanian Mathematical Society, May 25 - 26, 2018, Corabia, Romania;
  16. Buzatu R., A binary linear programming model for minimum convex partition of a graph.  Proceedings of the International Summer Mathematical School in Memoriam V. A. Plotnikov, June 11 - 16, 2018, Odessa, Ukraine, p. 89;
  17. Buzatu R., BLP modeling of the convex cover problem of a graph. Proceedings of the  International Scientific Conference “Modern Problems of Mathematics and Its Application in Natural Sciences and Information Technologies”, September 17 - 19, 2018, Chernivtsi, Ukraine, p. 124;
  18. Buzatu R., Improvement of the administrative-territorial structure using mixed integer linear programming. Proceedings of the 26th Conference on Applied and Industrial Mathematics (CAIM-2018), September 20 - 23, 2018, Chișinău, Moldova, p. 117;
  19. Buzatu R., A formulation of convex covering problem of graphs as a linear programming problem. Proceedings of the 6th International Conference “Mathematical Modeling, Optimization and Information Technologies”, Academy of transport, informatics and communication, November 12 - 16, 2018, Chișinău, Moldova, p. 48 - 49;
  20. Buzatu R., Cataranciuc S., On the difficulty of determining the maximum nontrivial convex cover number of a graph. Proceedings of the Thirteenth International Workshop “Discrete Mathematics and Its Applications, June 17 - 22, 2019, Moscow, Russia;
  21. Buzatu R., Optimization problems of general convex covering problem of graphs. Proceedings of the International Conference “Mathematics & Information Technologies: Research and Education” (MITRE – 2019), June 24 - 26, 2019, Chișinău, Moldova, p. 13;
  22. Buzatu R., Graph partitioning problems and their applications in socio-economic fields. Proceedings of the Ninth Conference of Romanian Mathematicians, June 28 - July 3, 2019, Galați, Romania, p. 18;
  23. Buzatu R., On the maximum nontrivial convex cover number of the join of graphs. Proceedings of the Fifth Conference of the Mathematical Society of the Republic of Moldova, September 28 – October 1, 2019, Chișinău, Moldova.
Other

 

List of scientific projects

  1. Project 11.817.08.49A (institutional project). Research theme: “Modern methodologies in software development” (2011-2014);
  2. Project 1C/2012 (bilateral projects with „Est Computer” company). Research theme: “Web 3.0 development” (2012);
  3. Project 15.820.18.02.03/B (bilateral projects with Belarus). Research theme: “Efficient models and algorithms for solving optimization problems on discrete structures” (2015-2016);
  4. Project 16.80012.02.03F (project for young scientist). Research theme: “Stochastic optimization algorithms” (2016-2018);
  5. Project 2017.3506.7-001.00 (Government project with GIZ cooperation). Research theme: “Support to Territorial-Administrative Reform in the Republic of Moldova” (2018);
  6. Project 15.817.02.37A (institutional project). Research theme: “Mathematical modeling and advanced computing in applied problems” (2015-2019);
  7. Project 20.80009.5007.13 (institutional project “Institute of Mathematics and Computer Science”). Research theme: “Deterministic and stochastic methods for solving optimization and control problems” (2020).