• Title/Summary/Keyword: [a, b]-factor

Search Result 5,565, Processing Time 0.034 seconds

MINIMUM DEGREE AND INDEPENDENCE NUMBER FOR THE EXISTENCE OF HAMILTONIAN [a, b]-FACTORS

  • Zhou, Sizhong;Pu, Bingyuan
    • Journal of applied mathematics & informatics
    • /
    • v.28 no.1_2
    • /
    • pp.325-331
    • /
    • 2010
  • Let a and b be nonnegative integers with 2 $\leq$ a < b, and let G be a Hamiltonian graph of order n with n > $\frac{(a+b-5)(a+b-3)}{b-2}$. An [a, b]-factor F of G is called a Hamiltonian [a, b]-factor if F contains a Hamiltonian cycle. In this paper, it is proved that G has a Hamiltonian [a, b]-factor if $\delta(G)\;\geq\;\frac{(a-1)n+a+b-3)}{a+b-3}$ and $\delta(G)$ > $\frac{(a-2)n+2{\alpha}(G)-1)}{a+b-4}$.

SHARP CONDITIONS FOR THE EXISTENCE OF AN EVEN [a, b]-FACTOR IN A GRAPH

  • Cho, Eun-Kyung;Hyun, Jong Yoon;O, Suil;Park, Jeong Rye
    • Bulletin of the Korean Mathematical Society
    • /
    • v.58 no.1
    • /
    • pp.31-46
    • /
    • 2021
  • Let a and b be positive integers, and let V (G), ��(G), and ��2(G) be the vertex set of a graph G, the minimum degree of G, and the minimum degree sum of two non-adjacent vertices in V (G), respectively. An even [a, b]-factor of a graph G is a spanning subgraph H such that for every vertex v ∈ V (G), dH(v) is even and a ≤ dH(v) ≤ b, where dH(v) is the degree of v in H. Matsuda conjectured that if G is an n-vertex 2-edge-connected graph such that $n{\geq}2a+b+{\frac{a^2-3a}{b}}-2$, ��(G) ≥ a, and ${\sigma}_2(G){\geq}{\frac{2an}{a+b}}$, then G has an even [a, b]-factor. In this paper, we provide counterexamples, which are highly connected. Furthermore, we give sharp sufficient conditions for a graph to have an even [a, b]-factor. For even an, we conjecture a lower bound for the largest eigenvalue in an n-vertex graph to have an [a, b]-factor.

An empirical study on the factors affecting the participation of B2B e-marketplace: from a perspective of buyers and sellers. (B2B e-marketplace의 참여도에 영향을 미치는 요인에 관한 연구 - 구매자와 공급자의 측면에서-*)

  • 김상수;강영구
    • Journal of Information Technology Applications and Management
    • /
    • v.9 no.4
    • /
    • pp.179-204
    • /
    • 2002
  • The purpose of this study is to empirically Investigate the critical success factors affecting the participation of B2B e-marketplace from a perspective of buyers and sellers. The research model presented in this study suggests that the success of B2B e-marketplace depends on the degree of participation of buyers and sellers. It is hypothesized that the participation of buyers and sellers is related with several contextual factors. The contextual factors included: (a) industry and market factor; (b) Internal environment factor; (c) product factor; (d) Inter-organizational factor; and (e) B2B e-marketplace system and strategy factor. An analysis of data from 31 buyer firms and 31 seller firms reveals that those five factors have a significant effect on the participation and success of B2B e-marketplace. The implications of the study are discussed and further research directions are proposed.

  • PDF

SHARP ORE-TYPE CONDITIONS FOR THE EXISTENCE OF AN EVEN [4, b]-FACTOR IN A GRAPH

  • Cho, Eun-Kyung;Kwon, Su-Ah;O, Suil
    • Journal of the Korean Mathematical Society
    • /
    • v.59 no.4
    • /
    • pp.757-774
    • /
    • 2022
  • Let a and b be positive even integers. An even [a, b]-factor of a graph G is a spanning subgraph H such that for every vertex v ∈ V (G), dH(v) is even and a ≤ dH(v) ≤ b. Let κ(G) be the minimum size of a vertex set S such that G - S is disconnected or one vertex, and let σ2(G) = minuv∉E(G) (d(u)+d(v)). In 2005, Matsuda proved an Ore-type condition for an n-vertex graph satisfying certain properties to guarantee the existence of an even [2, b]-factor. In this paper, we prove that for an even positive integer b with b ≥ 6, if G is an n-vertex graph such that n ≥ b + 5, κ(G) ≥ 4, and σ2(G) ≥ ${\frac{8n}{b+4}}$, then G contains an even [4, b]-factor; each condition on n, κ(G), and σ2(G) is sharp.

BINDING NUMBER AND HAMILTONIAN (g, f)-FACTORS IN GRAPHS

  • Cai, Jiansheng;Liu, Guizhen
    • Journal of applied mathematics & informatics
    • /
    • v.25 no.1_2
    • /
    • pp.383-388
    • /
    • 2007
  • A (g, f)-factor F of a graph G is Called a Hamiltonian (g, f)-factor if F contains a Hamiltonian cycle. The binding number of G is defined by $bind(G)\;=\;{min}\;\{\;{\frac{{\mid}N_GX{\mid}}{{\mid}X{\mid}}}\;{\mid}\;{\emptyset}\;{\neq}\;X\;{\subset}\;V(G)},\;{N_G(X)\;{\neq}\;V(G)}\;\}$. Let G be a connected graph, and let a and b be integers such that $4\;{\leq}\;a\;<\;b$. Let g, f be positive integer-valued functions defined on V(G) such that $a\;{\leq}\;g(x)\;<\;f(x)\;{\leq}\;b$ for every $x\;{\in}\;V(G)$. In this paper, it is proved that if $bind(G)\;{\geq}\;{\frac{(a+b-5)(n-1)}{(a-2)n-3(a+b-5)},}\;{\nu}(G)\;{\geq}\;{\frac{(a+b-5)^2}{a-2}}$ and for any nonempty independent subset X of V(G), ${\mid}\;N_{G}(X)\;{\mid}\;{\geq}\;{\frac{(b-3)n+(2a+2b-9){\mid}X{\mid}}{a+b-5}}$, then G has a Hamiltonian (g, f)-factor.

Derivation of Expected Mean Squares (EMS) Using Venn Diagram by the Type of Experimental Design (실험설계 유형별 Venn Diagram을 이용한 EMS 도출)

  • Choi, Sung-Woon
    • Proceedings of the Safety Management and Science Conference
    • /
    • 2011.04a
    • /
    • pp.695-699
    • /
    • 2011
  • The study presents an efficient design method of Venn Diagram that can be used when implementing the quality design of experiments based on generalizability theory. The paper examines four mixed and combined models that are designed by fixed factor, random factor, crossed factor and nested factor. The models considered in this research are $A^*{\times}B^*{\times}C$, (B: $A^*$)${\times}C$, $A{\times}B{\times}C$ and (B: A)${\times}C$.

  • PDF

Sulforaphane Inhibits Osteoclastogenesis by Inhibiting Nuclear Factor-κB

  • Kim, Soo-Jin;Kang, So-Young;Shin, Hyun-Hee;Choi, Hye-Seon
    • Molecules and Cells
    • /
    • v.20 no.3
    • /
    • pp.364-370
    • /
    • 2005
  • We show that sulforaphane inhibits osteoclastogenesis in the presence of macrophage colony-stimulating factor (M-CSF) and receptor for activation of nuclear factor-${\kappa}B$ ligand (RANKL) in osteoclast (OC) precursors. Sulforaphane, an aliphatic isothiocyanate, is a known cancer chemo-preventative agent with anti-oxidative properties. Nuclear factor-${\kappa}B$ (NF-${\kappa}B$) is a critical transcription factor in RANKL-induced osteoclastogenesis, and electrophoretic mobility shift assays (EMSAs) and assay of NF-${\kappa}B$-mediated secreted alkaline phosphatase (SEAP) revealed that sulforaphane selectively inhibited NF-${\kappa}B$ activation induced by RANKL. Inhibition may involve interaction of sulforaphane with thiol groups, since it was prevented by reducing agents.

Role of PI3-Kinase/Akt Pathway in the Activation of Etoposide-Induced $NF-{\kappa}B$ Transcription Factor

  • Choi Yong-Seok;Park Heon-Yong;Jeong Sun-Joo
    • Journal of Microbiology and Biotechnology
    • /
    • v.16 no.3
    • /
    • pp.391-398
    • /
    • 2006
  • $NF-{\kappa}B$ is a transcription factor involved in the innate immunity against bacterial infection and inflammation. It is also known to render cells resistant to the apoptosis caused by some anticancer drugs. Such a chemoresistance of cancer cells may be related to the activation of $NF-{\kappa}B$ transcription factor; however, the mechanism of activation is not well understood. Here, we demonstrate that a chemotherapeutic agent, etoposide, independently stimulates the $I{\kappa}B{\alpha}$ degradation pathway and PI3-kinase/Akt signaling pathway: The classical $I{\kappa}B{\alpha}$ degradation pathway leads to the nuclear translocation and DNA binding of p65 subunit through $IKK{\beta}$ kinase, whereas the PI3-kinase/Akt pathway plays a distinct role in activating this transcription factor. The PI3-kinase/Akt pathway acts on the p50 subunit of the $NF-{\kappa}B$ transcription factor and enhances the DNA binding affinity of the p50 protein. It may also explain the role of the PI3-kinase/Akt pathway in the anti-apoptotic function of $NF-{\kappa}B$ during chemoresistance of cancer cells.

BINDING NUMBER CONDITIONS FOR (a, b, k)-CRITICAL GRAPHS

  • Zhou, Sizhong
    • Bulletin of the Korean Mathematical Society
    • /
    • v.45 no.1
    • /
    • pp.53-57
    • /
    • 2008
  • Let G be a graph, and let a, b, k be integers with $0{\leq}a{\leq}b,k\geq0$. Then graph G is called an (a, b, k)-critical graph if after deleting any k vertices of G the remaining graph of G has an [a, b]-factor. In this paper, the relationship between binding number bind(G) and (a, b, k)-critical graph is discussed, and a binding number condition for a graph to be (a, b, k)-critical is given.

The Effect of e-CRM Factors on Customer Relationship Quality and Performance in B2B e-Marketplace -Focused on Moderating Effects of Switching Barriers (B2B e-마켓플레이스의 e-CRM요인이 고객관계의 질과 성과에 미치는 영향 -전환장벽의 조절효과를 중심으로-)

  • Song, Sun-Yok;Park, Kyu-Young
    • International Commerce and Information Review
    • /
    • v.13 no.4
    • /
    • pp.23-49
    • /
    • 2011
  • The of this study was to establish a theoretical basis for relationship marketing exercised in the mB e-Marketplace and to empirically analyze causal relationship among e-CRM factor, together with quality and the performance of the customer relationship. The population sample of this study was the companies who had experience for using the B2B e-Marketplace, and a data analysis was made through y analysis, factor analysis, multiple regression analysis and hierarchical regression analysis, utilizing statistical package of SPSS 18.0. The result of proving the are as follows; First, the e-CRM factors(e-Marketing, e-Service, e-Sales) of B2B e-Marketplace showed the positive influence on the customer relationship quality factor. the e-CRM factors of B2B e-Marketplace showed the positive influence on the customer relationship performance factor. Third, according to the test result on the relationship between quality factor and performance factor, customer relationship quality factor(satisfaction, trust) had positive effect on performance factor. Last, for the moderating effect of switching barrier in the customer relationship quality factor(satisfaction, trust) on the B2B e-Marketplace and its performance factor(reusing intention, long-term orientation) of maintaining the relation, the subordinate variables of switching barrier(alternative attraction, switching cost) showed the positive moderating effects.

  • PDF