HRZZ Research Project

Combinatorial Objects and Codes

(2019-2022)

University of Rijeka, Faculty of Mathematics

 

 

About the project

 

 

HRZZ

Papers:

  • M. Shi, Y. Li, W. Cheng, D. Crnkovic, D. Krotov, P. Solé, Self-dual bent sequences for complex Hadamard matrices, Des. Codes Cryptogr. 91 (2023), 1453-1474.

  • M. Shi, Y. Li, W. Cheng, D. Crnkovic, D. Krotov, P. Solé, Self-dual Hadamard bent sequences, J. Syst. Sci. Complex. 36 (2023), 894-908.

  • D. Crnkovic, F. Pavese, A. Švob, Intriguing sets of strongly regular graphs and their related structures, Contrib. Discrete Math. 18 (2023), 66-89.

  • V. Mikulic Crnkovic, I. Traunkar, Self-orthogonal codes constructed from weakly self-orthogonal designs invariant under an action of M11, Appl. Algebra Eng. Commun. Comput. 34 (2023), 139-156.

  • D. Crnkovic, A. Grbac, A. Švob, Formally self-dual LCD codes from two-class association schemes, Appl. Algebra Engrg. Comm. Comput. 34 (2023), 183-200.

  • D. Crnkovic, V. Mikulic Crnkovic, A. Švob, Construction of transitive q-analogs of designs, Math. Comput. Sci. 17 (2023), Paper No. 2, 5 pages.

  • S. Rukavina, V. D. Tonchev, Extremal ternary self-dual codes of length 36 and symmetric 2-(36,15,6) designs with an automorphism of order 2, J. Algebraic Combin. 57 (2023) 905-913.

  • M. Maksimovic, On Some Regular Two-Graphs up to 50 Vertices, Symmetry 15 (2023), 408.

  • D. R. Hawtin, J. Lansdown, The non-existence of block-transitive subspace designs, Combinatorial Theory 2, No. 1 (2022), Paper No. 11, 13 pp.

  • R. F. Bailey, D. R. Hawtin, On the classification of binary completely transitive codes with almost-simple top-group, European J. Combin. 107 (2023), 103604, 28 pp.

  • M. Abreu, M. Funk, V. Krcadinac, D Labbate, Strongly regular configurations, Des. Codes Cryptogr. 90 (2022), 1881-1897.

  • V. Krcadinac, Non-embeddable quasi-residual quasi-symmetric designs, Appl. Algebra Engrg. Comm. Comput. 33 (2022), 477-483.

  • K. Tabak, Note on Hamiltonian graphs Iin Abelian 2-groups, Kragujevac J. Math. 49 (2025), 401-409.

  • M. Buratti, A. Nakić, Super-regular Steiner 2-designs, Finite Fields Appl. 85 (2023), 102116, 29 pages.

  • D. Crnković, S. Rukavina, M. Šimac, LDPC codes constructed from cubic symmetric graphs, Appl. Algebra Engrg. Comm. Comput. 33 (2022), 505-522.

  • D. Crnković, A. Švob, Switching for 2-designs, Des. Codes Cryptogr. 90 (2022), 1585-1593.

  • D. Crnković, D. R. Hawtin, A. Švob, Neighbour-transitive codes and partial spreads in generalised quadrangles, Des. Codes Cryptogr. 90 (2022), 1521-1533.

  • M. Maksimović, S. Rukavina, New regular two-graphs on 38 and 42 vertices, Math. Commun. 27 (2022), 2, 151-161.

  • S. Ban, S. Rukavina, Type IV-II codes over Z4 constructed from generalized bent functions, Australasian journal of combinatorics, 84 (2022), 3, 341-356.

  • B. Fernandez, S. Rukavina, On the 2-Y-homogeneous condition of the incidence graphs of 2-designs, Graphs Combin. 38 (2022), 119, 15 pages

  • D. Crnković, T. Zrinski, Constructing block designs with a prescribed automorphism group using genetic algorithm, J. Combin. Des. 30 (2022), 515-526.

  • D. Crnković, S. Rukavina, M. Šimac, LDPC codes from cubic semisymmetric graphs, Ars Math. Contemp. 22 (2022), #P2.03, 13 pages.

  • D. Crnković, D. Dumicic Danilovic, R. Egan, A. Švob, Periodic Golay pairs and pairwise balanced designs, J. Algebraic Combin. 55 (2022), 245-257.

  • D. Crnković, S. Rukavina, A. Švob, Self-orthogonal codes from equitable partitions of association schemes, J. Algebraic Combin. 55 (2022), 157-171.

  • D. Crnković, S. Rukavina, New symmetric 2-(71,15,3) designs, Bull. Inst. Combin. Appl. 94 (2022), 79-94.

  • D. Crnković, A. Švob, New constructions of divisible design Cayley graphs, Graphs Combin. 38 (2022), 17, 8 pages.

  • V. Krčadinac, R. Vlahović Kruc, Quasi-symmetric designs on 56 points, Adv. Math. Commun. 15 (2021), 633-646.

  • D. Crnković, A. Švob, New symmetric 2-(176,50,14) designs, Discrete Math. 344 (2021), 112623, 3 pages.

  • V. Krčadinac, A new partial geometry pg(5,5,2), J. Combin. Theory Ser. A 183 (2021), 105493, 4 pages.

  • M. Knežević, V. Krčadinac, L. Relić, Matrix products of binomial coefficients and unsigned Stirling numbers, in: Proceedings of the 3rd Croatian Combinatorial Days (T. Došlić and S. Majstorović, Eds.), Faculty of Civil Engineering, University of Zagreb, 2021, 35-44.

  • D. R. Hawtin, s-Elusive codes in Hamming graphs, Des. Codes Cryptogr. 89 (2021), 1211–1220.

  • D. Crnković, D. Dumičić Danilović, S. Rukavina, On automorphism groups of a biplane (121,16,2), Discrete Math. 344 (2021), 112508, 8 pages.

  • D. Crnković, N. Mostarac, B. G. Rodrigues, L. Storme, s-PD-sets for codes from projective planes PG(2,2^h), 5 ≤ h ≤ 9, Adv. Math. Commun. 15 (2021), 423-440.

  • M. Buratti, A. Nakić, A. Wassermann, Graph decompositions in projective geometries, J. Combin. Des. 29 (2021), 141-174.

  • D. Crnković, R. Egan, B. G. Rodrigues, A. Švob, LCD codes from weighing matrices, Appl. Algebra Engrg. Comm. Comput. 32 (2021), 175–189.

  • D. Crnković, A. Švob, V. D. Tonchev, Strongly regular graphs with parameters (81,30,9,12) and a new partial geometry, J. Algebraic Combin. 53 (2021), 253-261.

  • D. Crnković, A. Švob, Application of tolerance graphs to combat COVID-19 pandemic, SN Comput. Sci. 2 (2021), 83, 8 pages.

  • R. F. Bailey, D. R. Hawtin, On the 486-vertex distance-regular graphs of Koolen-Riebeek and Soicher, Electron. J. Combin. 27 (2020), #P3.13, 12 pages.

  • D. Crnković, R. Egan, A. Švob, Self-orthogonal codes from orbit matrices of Seidel and Laplacian matrices of strongly regular graphs, Adv. Math. Commun. 14 (2020), 591-602.

  • S. Ban, S. Rukavina, On some new extremal Type II Z4-codes of length 40, Math. Commun. 25 (2020), 253-268.

  • D. Crnković, M. Maksimović, Strongly regular graphs with parameters (37,18,8,9) having nontrivial automorphisms, Art Discrete Appl. Math. 3 (2020), #P2.10, 8 pages.

  • J. D’haeseleer, J. Mannaert, L. Storme, A. Švob, Cameron-Liebler line classes in AG(3,q), Finite Fields Appl. 67 (2020), 101706, 17 pages.

  • D. Crnković, S. Rukavina, A. Švob, On some distance-regular graphs with many vertices, J. Algebraic Combin. 51 (2020), 641-652.

  • D. Crnković, M. Maksimović, Construction of strongly regular graphs having an automorphism group of composite order, Contrib. Discrete Math. 15 (2020), 22-41.

  • D. Crnković, F. Pavese, A. Švob, On the PSU(4,2)-invariant vertex-transitive strongly regular (216,40,4,8) graph, Graphs Combin. 36 (2020), 503-513.

  • D. Crnković, H. Kharaghani, A. Švob, Divisible design Cayley digraphs, Discrete Math. 343 (2020), 111784, 8 pages.

  • A. Švob, Transitive distance-regular graphs from linear groups L(3,q), q=2,3,4,5, Trans. Comb. 9 (2020) 49-60.

  • M. Maksimović, Self-orthogonal codes from row orbit matrices of strongly regular graphs, Sarajevo J. Math. 15(28) (2019), 309 – 322.

  • M. Buratti, M. Kiermaier, S. Kurz, A. Nakić, A. Wassermann, q -analogs of group divisible designs, in: K.-U. Schmidt, A. Winterhof (Eds.), Combinatorics and Finite Fields: Difference Sets, Polynomials, Pseudorandomness and Applications, in: Radon Series on Computational and Applied Mathematics, vol.23, 21-38, de Gruyter, Berlin, 2019.

  • S. Ban, D. Crnković, M. Mravić, S. Rukavina, New extremal Type II Z4-codes of length 32 obtained from Hadamard matrices, Discrete Math. Algorithms Appl. 11 (2019), 1950057, 18 pages.

  • A. Švob, Transitive distance-regular graphs from the unitary groups U(3,4), U(4,3) and U(5,2), Bull. Inst. Combin. Appl. 87 (2019), 103-113.

  • D. Crnković, A. Švob, V. D. Tonchev, Cyclotomic trace codes, Algorithms 2019, 12 (2019), 168, 10 pages.

  • M. De Boeck, M. Rodgers, L. Storme, A. Švob, Cameron-Liebler sets of generators in finite classical polar spaces, J. Combin. Theory Ser. A 167 (2019), 340-388.

  • M. Buratti, A. Nakić, Designs over finite fields by difference methods, Finite Fields Appl. 57 (2019), 128-138.

  • D. Crnković, S. Rukavina, M. Šimac, LDPC codes from μ-geodetic graphs obtained from block designs, Graphs Combin. 35 (2019), 451-469.

 

Talks:

  • D. Crnković, Pairwise balanced designs related to Periodic Golay pairs, 39th Colloqium on Combinatorics, KolKom2022, Paderborn, Germany, November 18 - 19, 2022.

  • A. Švob, LCD codes from equitable partitions of association schemes, 39th Colloqium on Combinatorics, KolKom2022, Paderborn, Germany, November 18 - 19, 2022.

  • D. Hawtin, Non-existence of block-transitive subspace Designs, Finite Geometries 2022, Sixth Irsee Conference, Irsee, Germany, August 28 - September 3, 2022.

  • V. Mikulić Crnković, 1-designs and related combinatorial structures and linear codes, 8th Czech-Slovak International Symposium on Graph Theory, Combinatorics, Algorithms and Applications (CSGT 2022), Prague, Czech Republic, July 25 - 29, 2022.

  • D. Crnković, Pairwise balanced designs and periodic Golay pairs, Minisymposium: Designs and Algebraic Structures, 29th British Combinatorial Conference, Lancaster, UK, July 11 - 15, 2022.

  • D. Hawtin, Neighbour-transitive codes in Kneser graphs, 29th British Combinatorial Conference, Lancaster, UK, July 11 - 15, 2022.

  • D. Crnković, Switching for 2-designs and Hadamard matrices, Combinatorial Constructions Workshop, Zagreb, Croatia, June 27 - 29, 2022.

  • A. Švob, On some constructions of divisible design Cayley graphs and digraphs, 24th Conference of the International Linear Algebra Society, Minisymposium on Designs and Codes Galway, Ireland, June 20 - 24, 2022.

  • D. Crnković, q-ary strongly regular graphs, 24th Conference of the International Linear Algebra Society, Minisymposium on Designs and Codes, Galway, Ireland, June 20 - 24, 2022.

  • M. Maksimović, Construction of strongly regular graphs having an automorphism group of composite order, 7th Split mathematical congress, Split, Croatia, June 15 - 18, 2022.

  • T. Zrinski, Constructions of block designs from orbit matrices using a modified genetic algorithm, 7th Split mathematical congress, Split, Croatia, June 15 - 18, 2022.

  • S. Rukavina, On some recent results on biplanes and triplanes, 14th Nordic Combinatorial Conference (NORCOM 2022), Tromso, Norway, June 7 - 9, 2022.

  • V. Krčadinac, On t-designs with three intersection numbers, 14th Nordic Combinatorial Conference (NORCOM 2022), Tromso, Norway, June 7 - 9, 2022.

  • I. Traunkar, Weakly p-self-orthogonal designs and LCD codes, Combinatorics 2022, Mantua, Italy , May 30 - Jun 3, 2022.

  • D. Hawtin, Nonexistence of Block-Transitive Subspace Designs, 43rd Australasian Combinatorics Conference, Melbourne, Australia, December 13 - 17, 2021.

  • A. Švob, On some periodic Golay pairs and pairwise balanced designs, 8th European Congress of Mathematics, Portorož, Slovenia, June 20 - 26, 2021.

  • K. Tabak, Dual incidences and t-designs in elementary abelian groups, 8th European Congress of Mathematics, Portorož, Slovenia, June 20 - 26, 2021.

  • T. Zrinski, Block designs constructed from orbit matrices using a modified genetic algorithm, 8th European Congress of Mathematics, Portorož, Slovenia, June 20 - 26, 2021.

  • N. Mostarac, s-PD-sets for codes from projective planes PG(2,2^h), 5≤h≤9, Graphs and Groups, Geometries and GAP (G2G2) Summer School, Rogla, Slovenia, June 27 - July 3, 2021

  • M. Šimac, LDPC codes from cubic semisymmetric graphs, Graphs and Groups, Geometries and GAP (G2G2) Summer School, Rogla, Slovenia, June 27 - July 23, 2021.

  • S. Rukavina, New extremal Type II Z4-codes of length 32 obtained from Hadamard matrices, 27th British Combinatorial Conference (BCC 2019), Birmingham, UK, July 29 - August 2, 2019.

  • T. Zrinski, Constructing block designs from orbit matrices using a modified genetic algorithm, 9th PhD Summer School in Discrete Mathematics, Rogla, Slovenia, June 30 - July 5, 2019.

  • M. Mravić, Hadamard matrices and Z4-linear codes, 9th PhD Summer School in Discrete Mathematics, Rogla, Slovenia, June 30 - July 5, 2019.

  • M. Šimac, LDPC codes constructed from cubic symmetric graphs, 9th Slovenian Conference on Graph Theory, Bled, Slovenia, June 23 - 29, 2019.

  • S. Ban, New extremal Type II Z4-codes of length 32 obtained from Hadamard designs, 9th Slovenian Conference on Graph Theory, Bled, Slovenia, June 23 - 29, 2019.

  • N. Mostarac, PD-sets for codes related to flag-transitive symmetric designs, Finite Geometry & Friends (a Brussels Summer School on Finite Geometry), Brussels, Belgium, June 17 - 21, 2019.

  • R. Vlahović Kruc, More quasi-symmetric 2-(56,16,6) designs, Finite Geometry & Friends (a Brussels Summer School on Finite Geometry), Brussels, Belgium, June 17 - 21, 2019.

  • V. Krčadinac, Generating orbits for quasi-symmetric designs, Finite Geometry Workshop 2019, Szeged, Hungary, January 31 - February 3, 2019.

 

PhD theses:

  • T. Zrinski, Constructing block designs and strongly regular graphs with prescribed automorphism group using genetic algorithms, October, 2022.

  • M. Mravić, An algorithm for construction of extremal and near- extremal Z4-codes, July, 2022.

  • I. Traunkar, Self-orthogonal and LCD codes obtained from weakly self-orthogonal designs, November 25, 2021.

  • A. Grbac, Self-dual and LCD codes from two class association schemes, November 12, 2020.

  • S. Ban, Construction of extremal Type II Z4-codes, July 8, 2019.

  • R. Vlahović Kruc, Some results on quasi-symmetric designs with exceptional parameters, July 4, 2019