Yusuf Civan

@w3.sdu.edu.tr

Mathematics
Süleyman Demirel University



                 

https://researchid.co/yusufcivan

RESEARCH, TEACHING, or OTHER INTERESTS

Discrete Mathematics and Combinatorics, Geometry and Topology

18

Scopus Publications

196

Scholar Citations

7

Scholar h-index

7

Scholar i10-index

Scopus Publications

  • Domination versus edge domination on claw-free graphs
    Yusuf Civan, Zakir Deniz, and Mehmet Akif Yetim
    Elsevier BV

  • Order-Sensitive Domination in Partially Ordered Sets and Graphs
    Yusuf Civan, Zakir Deniz, and Mehmet Akif Yetim
    Springer Science and Business Media LLC

  • The v-number and Castelnuovo–Mumford regularity of graphs
    Yusuf Civan
    Springer Science and Business Media LLC

  • Bounding the chromatic number of squares of K <inf>4</inf> -minor-free graphs
    Yusuf Civan, Zakir Deniz, and Mehmet Akif Yetim
    Elsevier BV

  • Prime graphs, matchings and the Castelnuovo-Mumford regularity
    Turker Biyikouglu and Yusuf Civan
    Rocky Mountain Mathematics Consortium

  • Castelnuovo-Mumford Regularity of Graphs
    Türker Biyikoğlu and Yusuf Civan
    Springer Science and Business Media LLC

  • Coloring hypercomplete and hyperpath graphs
    Yusuf CİVAN and Demet TAYLAN
    The Scientific and Technological Research Council of Turkey (TUBITAK-ULAKBIM) - DIGITAL COMMONS JOURNALS
    Given a graph G with an induced subgraph H and a family F of graphs, we introduce a (hyper)graph HH(G;F)=(VH, EH), the hyper-H (hyper)graph of G with respect to F, whose vertices are induced copies of H in G, and \\{H1,H2,\\ldots,Hr\\} \\in EH if and only if the induced subgraph of G by the set \\cupi=1r Hi is isomorphic to a graph F in the family F, and the integer r is the least integer for F with this property. When H is a k-complete or a k-path of G, we abbreviate HKk(G;F) and HPk(G;F) to Hk(G;F) and HPk(G;F), respectively. Our motivation to introduce this new (hyper)graph operator on graphs comes from the fact that the graph Hk(Kn;\\{K2k\\}) is isomorphic to the ordinary Kneser graph K(n;k) whenever 2k \\leq n. As a generalization of the Lovasz--Kneser theorem, we prove that c(Hk(G;\\{K2k\\}))=c(G)-2k+2 for any graph G with w(G)=c(G) and any integer k\\leq \\lfloor w(G)/2\\rfloor. We determine the clique and fractional chromatic numbers of Hk(G;\\{K2k\\}), and we consider the generalized Johnson graphs Hr(H;\\{Kr+1\\}) and show that c(Hr(H;\\{Kr+1\\}))\\leq c(H) for any graph H and any integer r< w(H). By way of application, we construct examples of graphs such that the gap between their chromatic and fractional chromatic numbers is arbitrarily large. We further analyze the chromatic number of hyperpath (hyper)graphs HPk(G;Pm), and we provide upper bounds when m=k+1 and m=2k in terms of the k-distance chromatic number of the source graph.

  • Vertex-decomposable graphs, codismantlability, cohen-macaulayness, and castelnuovo-mumford regularity


  • Upper Maximal Graphs of Posets
    Yusuf Civan
    Springer Science and Business Media LLC

  • Four-Cycled Graphs with Topological Applications
    Türker Bıyıkoğlu and Yusuf Civan
    Springer Science and Business Media LLC

  • Orphan complexes of neighborhood anti-sperner graphs


  • Open problems on linear Sperner families and lattices
    Yusuf Civan
    Akademiai Kiado Zrt.
    We introduce linear Sperner families and lattices, and provide some open problems.

  • A combinatorial shifting method on multicomplexes with applications to simplicial complexes and simple graphs


  • Linear colorings of simplicial complexes and collapsing
    Yusuf Civan and Ergün Yalçın
    Elsevier BV

  • Stably and almost complex structures on bounded flag manifolds
    Yusuf Civan
    American Mathematical Society (AMS)
    We study the enumeration problem of stably complex structures on bounded flag manifolds arising from omniorientations, and determine those induced by almost complex structures. We also enumerate the stably complex structures on these manifolds which bound, therefore representing zero in the complex cobordism ring Ω ∗ U \\Omega _*^U .

  • Bott towers, crosspolytopes and torus actions
    Yusuf Civan
    Springer Science and Business Media LLC


  • KO-groups of bounded flag manifolds


RECENT SCHOLAR PUBLICATIONS

  • Domination versus edge domination on claw-free graphs
    Y Civan, Z Deniz, MA Yetim
    Discrete Applied Mathematics 337, 171-172 2023

  • Order-Sensitive Domination in Partially Ordered Sets and Graphs
    Y Civan, Z Deniz, MA Yetim
    Order 40 (1), 157-172 2023

  • The v-number and Castelnuovo–Mumford regularity of graphs
    Y Civan
    Journal of Algebraic Combinatorics 57 (1), 161-169 2023

  • Bounding the collapsibility number of simplicial complexes and graphs
    T Bıyıkoğlu, Y Civan
    arXiv preprint arXiv:2201.13046 2022

  • Bounding the collapsibility number of simplicial complexes and graphs
    T Biyikoglu, Y Civan
    arXiv preprint arXiv:2201.13046 2022

  • Bounding the chromatic number of squares of K4-minor-free graphs
    Y Civan, Z Deniz, MA Yetim
    Discrete Mathematics 342 (7), 1894-1903 2019

  • Prime graphs, matchings and the Castelnuovo-Mumford regularity
    T Biyikouglu, Y Civan
     2019

  • A NOTE ON THE RECOGNITION OF CODISMANTLABLE GRAPHS AND POSETS
    T BIYIKOGLU, Y CIVAN
     2016

  • Projective dimension of (hyper) graphs and the Castelnuovo-Mumford regularity of bipartite graphs
    T Bıyıkoğlu, Y Civan
    arXiv preprint arXiv:1605.02956 2016

  • Castelnuovo-Mumford regularity of graphs
    T Biyikoglu, Y Civan
    arXiv preprint arXiv:1503.06018 2015

  • izgilerin Castelnuovo-Mumford reglaritesi ve dng-kıran komplekslerin topolojisi
    Y Civan, T Bıyıkoğlu
    TBİTAK-Trkiye Bilimsel ve Teknolojik Araştırma Kurumu 2014

  • Coloring hypercomplete and hyperpath graphs
    Y Civan, D Taylan
    Turkish Journal of Mathematics 38 (1), 1-15 2014

  • Upper maximal graphs of posets
    Y Civan
    Order 30, 677-688 2013

  • Bounding Castelnuovo-Mumford regularity of graphs via Lozin's transformation
    T Biyikoglu, Y Civan
    arXiv preprint arXiv:1302.3064 2013

  • ODT-BİLKENT Algebraic Geometry Seminar
    AS Sertz, Kişisel, Y Ozan, F Arslan, H nsiper, A Degtyarev, ...
     2012

  • Vertex decomposable graphs, codismantlability, Cohen-Macaulayness and Castelnuovo-Mumford regularity
    T Biyikoglu, Y Civan
    arXiv preprint arXiv:1205.5631 2012

  • Four-cycled graphs with topological applications
    T Bıyıkoğlu, Y Civan
    Annals of Combinatorics 16, 37-56 2012

  • AMS Subject Classification: 57Q10, 05C38; 05C75
    T Bıyıkoglu, Y Civan
    Annals of Combinatorics 16 (1), 37-56 2012

  • VERTEX DECOMPOSABLE GRAPHS, CODISMANTLABILITY, COHEN-MACAULAYNESS AND CASTELNUOVO-MUMFORD REGULARITY
    TB GLU, Y CIVAN
     2011

  • HYPERCOMPLETE GRAPHS AND THE GENERALIZED LOVASZ-KNESER THEOREM
    Y CIVAN, D TAYLAN
     2010

MOST CITED SCHOLAR PUBLICATIONS

  • Vertex decomposable graphs, codismantlability, Cohen-Macaulayness and Castelnuovo-Mumford regularity
    T Biyikoglu, Y Civan
    arXiv preprint arXiv:1205.5631 2012
    Citations: 46

  • Homotopy decompositions and K-theory of Bott towers
    Y Civan, N Ray
    arXiv preprint math/0408261 2004
    Citations: 38

  • Linear colorings of simplicial complexes and collapsing
    Y Civan, E Yalın
    Journal of Combinatorial Theory, Series A 114 (7), 1315-1331 2007
    Citations: 22

  • Castelnuovo-Mumford regularity of graphs
    T Biyikoglu, Y Civan
    arXiv preprint arXiv:1503.06018 2015
    Citations: 15

  • Bounding Castelnuovo-Mumford regularity of graphs via Lozin's transformation
    T Biyikoglu, Y Civan
    arXiv preprint arXiv:1302.3064 2013
    Citations: 12

  • Bott towers, crosspolytopes and torus actions
    Y Civan
    Geometriae Dedicata 113, 55-74 2005
    Citations: 12

  • The v-number and Castelnuovo–Mumford regularity of graphs
    Y Civan
    Journal of Algebraic Combinatorics 57 (1), 161-169 2023
    Citations: 11

  • Some examples in toric geometry
    Y Civan
    arXiv preprint math/0306029 2003
    Citations: 7

  • Homotopy decompositions and
    Y Civan, N Ray
    K, 1-33
    Citations: 6

  • Bounding the chromatic number of squares of K4-minor-free graphs
    Y Civan, Z Deniz, MA Yetim
    Discrete Mathematics 342 (7), 1894-1903 2019
    Citations: 5

  • Topology of families of toric manifolds
    Y Civan
    PQDT-Global 2000
    Citations: 5

  • Upper maximal graphs of posets
    Y Civan
    Order 30, 677-688 2013
    Citations: 4

  • Four-cycled graphs with topological applications
    T Bıyıkoğlu, Y Civan
    Annals of Combinatorics 16, 37-56 2012
    Citations: 4

  • Projective dimension of (hyper) graphs and the Castelnuovo-Mumford regularity of bipartite graphs
    T Bıyıkoğlu, Y Civan
    arXiv preprint arXiv:1605.02956 2016
    Citations: 2

  • Open problems on linear Sperner families and lattices
    Y Civan
    Studia Scientiarum Mathematicarum Hungarica 45 (4), 563-568 2008
    Citations: 2

  • Domination versus edge domination on claw-free graphs
    Y Civan, Z Deniz, MA Yetim
    Discrete Applied Mathematics 337, 171-172 2023
    Citations: 1

  • Bounding the collapsibility number of simplicial complexes and graphs
    T Biyikoglu, Y Civan
    arXiv preprint arXiv:2201.13046 2022
    Citations: 1

  • Prime graphs, matchings and the Castelnuovo-Mumford regularity
    T Biyikouglu, Y Civan
     2019
    Citations: 1

  • Stably and almost complex structures on bounded flag manifolds
    Y Civan
    Proceedings of the American Mathematical Society 134 (5), 1537-1548 2006
    Citations: 1

  • KO-groups of bounded flag manifolds
    Y Civan
    Turkish Journal of Mathematics 26 (4), 447-464 2002
    Citations: 1