201,224 research outputs found
Enumerating typical circulant covering projections onto a circulant graph
No full textEnumerating the isomorphism classes of several types of graph covering projections is one of the central research topics in enumerative topological graph theory ( see [ S. F. Du, D. Marusic, and A. O. Waller, J. Combin. Theory Ser. B, 74 ( 1998), pp. 276 - 290], [ S. F. Du, J. H. Kwak, and M. Y. Xu, J. Combin. Theory Ser. B, 93 ( 2005), pp. 73 - 93], [ R. Feng, J. H. Kwak, J. Kim, and J. Lee, SIAM J. Discrete Math., 11 ( 1998), pp. 265 - 272], [ R. Feng. and J. H. Kwak, Discrete Math., 277 ( 2004), pp. 73 - 85], [ C. D. Godsil and A. D. Hensel, J. Combin. Theory Ser. B., 56 ( 1992), pp. 205 - 238], [ M. Hofmeister, Discrete Math., 143 ( 1995), pp. 87 - 97], [ M. Hofmeister, SIAM J. Discrete Math., 8 ( 1995), pp. 51 - 61], [ M. Hofmeister, SIAM J. Discrete Math., 11 ( 1998), pp. 286 - 292], [ J. H. Kwak, J. Chun, and J. Lee, SIAM J. Discrete Math., 11 ( 1998), pp. 273 - 285], [ J. H. Kwak and J. Lee, Canad. J. Math., 42 ( 1990), pp. 747 - 761], and [ J. H. Kwak and J. Lee, Combinatorial and Computational Mathematics: Present and Future, ( 2001), pp. 97 - 161]). A covering projection is called circulant if its covering graph is circulant. A covering projection p from a Cayley graph Cay( A, X) onto another Cay( Q, Y) is called typical if the map p : A --> Q on the vertex sets is a group homomorphism from A onto Q. In [ R. Feng. and J. H. Kwak, Discrete Math., 277 ( 2004), pp. 73 - 85], the authors enumerated the isomorphism classes of typical circulant double covering projections onto a circulant graph. As a continuation of this work, we enumerate in this paper the isomorphism classes of those covering projections of any folding number.open115sciescopu
ENUMERATING TYPICAL ABELIAN PRIME-FOLD COVERINGS OF A CIRCULANT GRAPH
No full textEnumerating the isomorphism classes of several types of graph coverings is one of the central research topics in enumerative topological graph theory (see [R. Feng, J.H. Kwak, J. Kim, J. Lee, Isomorphism classes of concrete graph coverings, SIAM J. Discrete Math. 11 (1998) 265-272; R. Feng, J.H. Kwak, Typical circulant double coverings of a circulant graph, Discrete Math. 277 (2004) 73-85; R. Feng,J.H. Kwak, Y.S. Kwon, Enumerating typical circulant covering projections onto a circulant graph, SIAM J. Discrete Math. 19 (2005) 196-207; SIAM J. Discrete Math. 21 (2007) 548-550 (erratum); M. Hofmeister, Graph covering projections arising from finite vector spaces over finite fields, Discrete Math. 143 (1995) 87-97; M. Hofmeister, Enumeration of concrete regular covering projections, SIAM J. Discrete Math. 8 (1995) 51-61; M. Hofmeister, A note on counting connected graph covering projections, SIAM J. Discrete Math. 11 (1998) 286-292; J.H. Kwak, J. Chun, J. Lee, Enumeration of regular graph coverings having finite abelian covering transformation groups, SIAM J. Discrete Math. 11 (1998) 273-285; J.H. Kwak, J. Lee, Isomorphism classes of graph bundles, Canad. J. Math. XLlI (1990) 747-761]). A covering is called abelian (or circulant, respectively) if its covering graph is a Cayley graph on an abelian (or a cyclic, respectively) group. A covering p from a Cayley graph Cay(A, X) onto another Cay (Q, Y) is called typical if the map p : A -> Q on the vertex sets is a group epimorphism. Recently, the isomorphism classes of connected typical circulant r-fold coverings of a circulant graph are enumerated in [R. Feng, J.H. Kwak, Typical circulant double coverings of a circulant graph, Discrete Math. 277 (2004) 73-85] for r = 2 and in [R. Feng, J.H. Kwak, Y.S. Kwon, Enumerating typical circulant covering projections onto a circulant graph, SIAM J. Discrete Math. 19 (2005) 196-207; SIAM J. Discrete Math. 21 (2007) 548-550 (erratum)] for any r. As a continuation of these works, we enumerate in this paper the isomorphism classes of typical abelian prime-fold coverings of a circulant graph. (C) 2008 Elsevier B.V. All rights reserved.X112sciescopu
Ixodes heathi Kwak, 2018 in Kwak et al. 2018
No full text97. Ixodes heathi Kwak, 2018 in Kwak et al. (2018). An Australasian species known only to parasitize Diprotodontia: Burramyidae. M: unknown F: unknown N: Kwak et al. (2018) L: unknown Redescriptions: nonePublished as part of Guglielmone, Alberto A., Petney, Trevor N. & Robbins, Richard G., 2020, Ixodidae (Acari: Ixodoidea): descriptions and redescriptions of all known species from 1758 to December 31, 2019, pp. 1-322 in Zootaxa 4871 (1) on page 33, DOI: 10.11646/zootaxa.4871.1.1, http://zenodo.org/record/442334
Enumerating branched orientable surface coverings over a non-orientable surface
No full textThe isomorphism classes of several types of graph coverings of a graph have been enumerated by many authors [M. Hofmeister, Graph covering projections arising from finite vector space over finite fields, Discrete Math. 143 (1995) 87-97; S. Hong, J.H. Kwak, J. Lee, Regular graph coverings whose covering transformation groups have the isomorphism extention property, Discrete Math. 148 (1996) 85-105; J.H. Kwak, J.H. Chun, J.Lee, Enumeration of regular graph coverings having finite abelian covering transformation groups, SIAM J. Discrete Math. 11 (1998) 273-285; J.H. Kwak, J. Lee, Isomorphism classes of graph bundles, Canad. J. Math. XLII (1990) 747-761; J.H. Kwak, J. Lee, Enumeration of connected graph coverings, J. Graph Theory 23 (1996) 105-109]. Recently, Kwak et at [Balanced regular coverings of a signed graph and regular branched orientable surface coverings over a non-orientable surface, Discrete Math. 275 (2004) 177-193] enumerated the isomorphism classes of balanced regular coverings of a signed graph, as a continuation of an enumeration work done by Archdeacon et al [Bipartite covering graphs, Discrete Math. 214 (2000) 51-63] the isomorphism classes of branched orientable regular surface coverings of a non-orientable surface having a finite abelian covering transformation group. In this paper, we enumerate the isomorphism classes of connected balanced (regular or irregular) coverings of a signed graph and those of unbranched orientable coverings of a non-orientable surface, as an answer of the question raised by Liskovets [Reductive enumeration under mutually orthogonal group actions, Acta-Appl.Math. 52 (1998) 91-120]. As a consequence of these two results, we also enumerate the isomorphism classes of branched orientable surface coverings of a non-orientable surface. (c) 2005 Elsevier B.V. All rights reserved.X112sciescopu
Enumerating typical abelian prime-fold coverings of a circulant graph
No full textAbstractEnumerating the isomorphism classes of several types of graph coverings is one of the central research topics in enumerative topological graph theory (see [R. Feng, J.H. Kwak, J. Kim, J. Lee, Isomorphism classes of concrete graph coverings, SIAM J. Discrete Math. 11 (1998) 265–272; R. Feng, J.H. Kwak, Typical circulant double coverings of a circulant graph, Discrete Math. 277 (2004) 73–85; R. Feng, J.H. Kwak, Y.S. Kwon, Enumerating typical circulant covering projections onto a circulant graph, SIAM J. Discrete Math. 19 (2005) 196–207; SIAM J. Discrete Math. 21 (2007) 548–550 (erratum); M. Hofmeister, Graph covering projections arising from finite vector spaces over finite fields, Discrete Math. 143 (1995) 87–97; M. Hofmeister, Enumeration of concrete regular covering projections, SIAM J. Discrete Math. 8 (1995) 51–61; M. Hofmeister, A note on counting connected graph covering projections, SIAM J. Discrete Math. 11 (1998) 286–292; J.H. Kwak, J. Chun, J. Lee, Enumeration of regular graph coverings having finite abelian covering transformation groups, SIAM J. Discrete Math. 11 (1998) 273–285; J.H. Kwak, J. Lee, Isomorphism classes of graph bundles, Canad. J. Math. XLII (1990) 747–761]). A covering is called abelian (or circulant, respectively) if its covering graph is a Cayley graph on an abelian (or a cyclic, respectively) group. A covering p from a Cayley graph Cay(A,X) onto another Cay (Q,Y) is called typical if the map p:A→Q on the vertex sets is a group epimorphism. Recently, the isomorphism classes of connected typical circulant r-fold coverings of a circulant graph are enumerated in [R. Feng, J.H. Kwak, Typical circulant double coverings of a circulant graph, Discrete Math. 277 (2004) 73–85] for r=2 and in [R. Feng, J.H. Kwak, Y.S. Kwon, Enumerating typical circulant covering projections onto a circulant graph, SIAM J. Discrete Math. 19 (2005) 196–207; SIAM J. Discrete Math. 21 (2007) 548–550 (erratum)] for any r. As a continuation of these works, we enumerate in this paper the isomorphism classes of typical abelian prime-fold coverings of a circulant graph
Enumeration of regular graph coverings having finite abelian covering transformation groups
No full textSeveral isomorphism classes of graph coverings of a graph G have been enumerated by many authors. An enumeration of the isomorphism classes of n-fold coverings of a graph G was done by Kwak and Lee [Canad. J. Math., XLII (1990), pp. 747-761] and independently by Hofmeister [Discrete Math., 98 (1991), pp. 437-444]. An enumeration of the isomorphism classes of connected n-fold coverings of a graph G was recently done by Kwak and Lee [J. Graph Theory, 23 (1996), pp. 105-109]. But the enumeration of the isomorphism classes of regular coverings of a graph G has been done for only a few cases. In fact, the isomorphism classes of A-coverings of G were enumerated when A is the cyclic group Z(n), the dihedral group D-n (n: odd), and the direct sum of m copies of Z(p). (See [Discrete Math., 143 (1995), pp. 87-97], [J. Graph Theory, 15 (1993), pp. 621-627], and [Discrete Math., 148 (1996), pp. 85-105]). In this paper, we discuss a method to enumerate the isomorphism classes of connected A-coverings of a graph G for any finite group A and derive some formulas for enumerating the isomorphism classes of regular n-fold coverings for any natural number n. In particular, we calculate the number of the isomorphism classes of A-coverings of G when A is a finite abelian group or the dihedral group D-n. Our method gives partial answers to the open problems 1 and 2 in [Discrete Math., 148 (1996), pp. 85-105] and also gives a formula to calculate the number of the subgroups of a given index of any finitely generated free abelian group.open1120sciescopu
MAPK Cascades in Guard Cell Signal Transduction
Get PDFGuard cells form stomata on the epidermis and continuously respond to endogenous and environmental stimuli to fine-tune the gas exchange and transpirational water loss, processes which involve mitogen-activated protein kinase (MAPK) cascades. MAPKs form three-tiered kinase cascades with MAPK kinases and MAPK kinase kinases, by which signals are transduced to the target proteins. MAPK cascade genes are highly conserved in all eukaryotes, and they play crucial roles in myriad developmental and physiological processes. MAPK cascades function during biotic and abiotic stress responses by linking extracellular signals received by receptors to cytosolic events and gene expression. In this review, we highlight recent findings and insights into MAPK-mediated guard cell signaling, including the specificity of MAPK cascades and the remaining questions. Copyright © 2016 Lee, Kim, Kim and Kwak. This is an open-access article distributed
under the terms of the Creative Commons Attribution License(CCBY).120231sciescopu
FIGURES 21–25 in A revision of the Australian genus Trachylestes with the description of two new species (Hemiptera: Heteroptera: Reduviidae: Harpactorinae)
No full textFIGURES 21–25, Trachylestes queenslandensis, paratype female: 21, syntergite 9/10; 22, bursa copulatrix, in lateral view; 23, egg without operculum, lateral view; 24, operculum, dorsal view; 25, same, ventral view. Abbreviations: gap 8, gonapophysis 8; gap 9, gonapophysis 9; gcx 9, gonocoxa 9; gpl, gonoplac; prj, anterior projections of gonapophysis 8.Published as part of Malipatil, M. B., Kwak, M. L. & Gunawardene, N., 2016, A revision of the Australian genus Trachylestes with the description of two new species (Hemiptera: Heteroptera: Reduviidae: Harpactorinae), pp. 88-100 in Zootaxa 4105 (1) on page 98, DOI: 10.11646/zootaxa.4105.1.4, http://zenodo.org/record/26469
COLUMN MEAN VANISHING MATRICES
No full textIn this paper, we study some properties of a special class of matrices having orthonormal columns. These matrices appear in some applications, especially in wireless communications. We study the column property and spectral decomposition. Using these properties, we suggest a new method of generating such matrices. For N even, the new method gives rise to a matrix which is more efficient. Numerical examples to compare two methods are included. © 2017 Academic Publications, Ltd.
Genera of Cayley maps
No full textThe genus distribution of a graph G is defined to be the sequence {g (m) }, where g (m) is the number of different embeddings of G in the closed orientable surface of genus m. In this paper, we examine the genus distributions of Cayley maps for several Cayley graphs. It will be shown that the genus distribution of Cayley maps has many different properties from its usual genus distribution.11sciescopu
- …
