• 제목/요약/키워드: Number theory

검색결과 2,587건 처리시간 0.028초

COMPUTATION OF TOTAL CHROMATIC NUMBER FOR CERTAIN CONVEX POLYTOPE GRAPHS

  • A. PUNITHA;G. JAYARAMAN
    • Journal of applied mathematics & informatics
    • /
    • 제42권3호
    • /
    • pp.567-582
    • /
    • 2024
  • A total coloring of a graph G is an assignment of colors to the elements of a graphs G such that no adjacent vertices and edges receive the same color. The total chromatic number of a graph G , denoted by χ''(G), is the minimum number of colors that suffice in a total coloring. In this paper, we proved the Behzad and Vizing conjecture for certain convex polytope graphs Dpn, Qpn, Rpn, En, Sn, Gn, Tn, Un, Cn,respectively. This significant result in a graph G contributes to the advancement of graph theory and combinatorics by further confirming the conjecture's applicability to specific classes of graphs. The presented proof of the Behzad and Vizing conjecture for certain convex polytope graphs not only provides theoretical insights into the structural properties of graphs but also has practical implications. Overall, this paper contributes to the advancement of graph theory and combinatorics by confirming the validity of the Behzad and Vizing conjecture in a graph G and establishing its relevance to applied problems in sciences and engineering.

홍정하(洪正夏)의 수론(數論) (Hong Jung Ha's Number Theory)

  • 홍성사;홍영희;김창일
    • 한국수학사학회지
    • /
    • 제24권4호
    • /
    • pp.1-6
    • /
    • 2011
  • 조선의 가장 위대한 산학자 홍정하(洪正夏)의 저서 $\ll$구일집(九一集)$\gg$(1724)에 들어있는 최소공배수를 구하는 법을 조사하여 홍정하의 수론에 대한 업적을 밝혀낸다. 홍정하는 두 자연수 a, b의 최대공약수 d와 최소공배수 l 에 대하여 l = $a\frac{b}{d}$=$b\frac{a}{d}$, $\frac{a}{d}$, $\frac{b}{d}$는 서로 소인 것을 인지하여, 자연수 $a_1,\;a_2,{\ldots},a_n$의 최대공약수 D에 대하여, $\frac{a_i}{D}$($1{\leq}i{\leq}n$)도 서로 소이고, 이들의 최소공배수 L도 서로 소인 $c_i(1{\leq}i{\leq}n)$가 존재하여 L = $a_ic_i(1{\leq}i{\leq}n)$임을 보였다. 이 결과는 조선에서 얻어낸 수론에 관한 수학적 업적 중에 가장 뛰어난 것 중의 하나이다. 홍정하가 수학적 구조를 밝혀내는 과정을 드러내는 것이 이 논문의 목적이다.

현상학적 불확실성 인자를 가진 사고진행사건수목의 분석을 위한 퍼지 집합이론의 응용 (Application of the Fuzzy Set Theory to Analysis of Accident Progression Event Trees with Phenomenological Uncertainty Issues)

  • Ahn, Kwang-Il;Chun, Moon-Hyun
    • Nuclear Engineering and Technology
    • /
    • 제23권3호
    • /
    • pp.285-298
    • /
    • 1991
  • 전형적인 정성적 퍼지형태의 입력데이타를 가진, 주어진 사고진행사건수목의 일부분에 대하여 퍼지집합이론(fuzzy set theory)의 응용 예를 먼저 보여주고, 이 예를 통해서 퍼지집합이론을 사고 진행사건수목에 적용하기 위해 적절한 계산알고리즘을 찾아내고 또 예를 들어 설명하였다. 그리고, 간단한 예제에 사용한 계산절차를 많은 현상학적 불확실성 인자를 포함한 아주 복잡한 사고진행사건수목 즉, 최근 Zion 발전소 위험도평가(PRA)에 사용된 전형적인 발전소 손상군의 하나인‘SEC’에 응용해서 적용하였다. 퍼지집합이론으로 평가한 계산값들의 퍼지평균치들은 최근 통계적 PRA 평가 방법론으로 얻는 값들의 평균치와 거의 같은 결과를 보여주고 있다. 본 논문의 주요목적은 부정확하고 또 정성적인 분기점확률이나 또는 많은 현상학적 불확실성 인자들을 가진 사고진행사건수목들에 이 퍼지집합이론을 적용하기 위한 공식적 계산절차를 제공하는데 있다.

  • PDF

Thermal buckling analysis of thick anisotropic composite plates by finite strip method

  • Cheung, M.S.;Akhras, G.;Li, W.
    • Structural Engineering and Mechanics
    • /
    • 제7권5호
    • /
    • pp.473-484
    • /
    • 1999
  • In the present study, the thermal buckling analysis of thick anisotropic laminated composite plates is carried out using the finite strip method based on the higher-order shear deformation theory. This theory accounts for the parabolic distribution of the transverse shear strains through the thickness of the plate and for zero transverse shear stresses on the plate surfaces. Therefore, this theory yields improved results over the Mindlin plate theory and eliminates the need for shear correction factors in calculating the transverse shear stiffness. The critical temperatures of simply supported rectangular cross-ply and angle-ply composite laminates are calculated. The effects of several parameters, such as the aspect ratio, the length-to-thickness ratio, the number of plies, fibre orientation and stacking sequence, are investigated.

특별직교이방성 이론에 의한 포스트 텐션된 교량의 해석(II) - 강 판형교 - (Analysis of Post-tensioned Bridge by Specially Orthotropic Laminate Theory (II) - Steel Plate Girder Bridge)

  • 김덕현;원치문;이정호
    • 한국복합재료학회:학술대회논문집
    • /
    • 한국복합재료학회 2001년도 춘계학술발표대회 논문집
    • /
    • pp.141-146
    • /
    • 2001
  • A post-tensioned steel plate girder bridge with cross-beams is analyzed by specially orthotropic laminate theory. The cross-sections of both girders and cross-beams are WF types. The result is compared with that of the beam theory. This bridge with simple support is under uniformly distributed vertical load, and axial loads and moment due to post-tension. In this paper, finite difference method for numerical analysis of simple supported bridge is developed. Relatively exact solution is obtained even with small number of meshes. Theory and analysis method of specially orthotropic laminate plates used in this paper can be used in design of new bridges, and maintenance and repair of old bridges.

  • PDF

Division Algorithm in SuanXue QiMeng

  • 홍성사;홍영희;이승온
    • 한국수학사학회지
    • /
    • 제26권5_6호
    • /
    • pp.323-328
    • /
    • 2013
  • The Division Algorithm is known to be the fundamental foundation for Number Theory and it leads to the Euclidean Algorithm and hence the whole theory of divisibility properties. In JiuZhang SuanShu(九章算術), greatest common divisiors are obtained by the exactly same method as the Euclidean Algorithm in Elements but the other theory on divisibility was not pursued any more in Chinese mathematics. Unlike the other authors of the traditional Chinese mathematics, Zhu ShiJie(朱世傑) noticed in his SuanXue QiMeng(算學啓蒙, 1299) that the Division Algorithm is a really important concept. In [4], we claimed that Zhu wrote the book with a far more deeper insight on mathematical structures. Investigating the Division Algorithm in SuanXue QiMeng in more detail, we show that his theory of Division Algorithm substantiates his structural apporaches to mathematics.

Influence of material composition on buckling response of FG plates using a simple plate integral model

  • Bakhti, Karima;Sekkal, Mohamed;Adda Bedia, E.A.;Tounsi, Abdelouahed
    • Smart Structures and Systems
    • /
    • 제25권4호
    • /
    • pp.447-457
    • /
    • 2020
  • In this study, a simple two-dimensional shear deformation model is employed for buckling analysis of functionally graded (FG) plates. The proposed theory has a kinematic with integral terms which considers the influence of shear deformation without using "shear correction factors". The impact of varying material properties and volume fraction of the constituent on buckling response of the FG plate is examined and discussed. The benefit of this theory over other contributions is that a number of variables is reduced. The basic equations that consider the influence of transverse shear stresses are derived from the principle of virtual displacements. The analytical solutions are obtained utilizing the "Navier method". The accuracy of the proposed theory is proved by comparisons with the different solutions found in the literature.

Recent Progresses in the Linguistic Modeling of Biological Sequences Based on Formal Language Theory

  • Park, Hyun-Seok;Galbadrakh, Bulgan;Kim, Young-Mi
    • Genomics & Informatics
    • /
    • 제9권1호
    • /
    • pp.5-11
    • /
    • 2011
  • Treating genomes just as languages raises the possibility of producing concise generalizations about information in biological sequences. Grammars used in this way would constitute a model of underlying biological processes or structures, and that grammars may, in fact, serve as an appropriate tool for theory formation. The increasing number of biological sequences that have been yielded further highlights a growing need for developing grammatical systems in bioinformatics. The intent of this review is therefore to list some bibliographic references regarding the recent progresses in the field of grammatical modeling of biological sequences. This review will also contain some sections to briefly introduce basic knowledge about formal language theory, such as the Chomsky hierarchy, for non-experts in computational linguistics, and to provide some helpful pointers to start a deeper investigation into this field.

Optimality Theory in Semantics and the Anaphora Resolution in Korean: An Adumbration

  • Hong, Min-Pyo
    • 한국언어정보학회지:언어와정보
    • /
    • 제6권2호
    • /
    • pp.129-152
    • /
    • 2002
  • This paper argues for a need to adopt a conceptually radical approach to zero anaphora resolution in Korean. It is shown that a number of apparently conflicting constraints, mostly motivated by lexical, syntactic, semantic, and pragmatic factors, are involved in determining the referential identity of zero pronouns in Korean. It is also argued that some of the major concepts of Optimality Theory can provide a good theoretical framework to predict the antecedents to zero pronouns in general. A partial formalization of 07-based constraints at the morpho-syntactic and lexico-semantical level is provided. It is argued that the lexico-semantic restrictions on adjacent expressions play the most important role in the anaphora resolution process along with a variant of the binding principle, formulated in semantic terms. Other pragmatically motivated constraints that incorporate some important intuitions of Centering Theory are proposed too.

  • PDF

Free vibration of laminated composite plates in thermal environment using a simple four variable plate theory

  • Yahea, Hussein T.;Majeed, Widad I.
    • Composite Materials and Engineering
    • /
    • 제3권3호
    • /
    • pp.179-199
    • /
    • 2021
  • A simple solution for free vibration of cross-ply and angle-ply laminated composite plates in a thermal environment is investigated using a basic trigonometric shear deformation theory. By application of trigonometric four variable plate theory, the transverse displacement is subdivided into bending and shear components, the present theory's number of unknowns and governing equations is reduced, making it easier to use. Hamilton's Principle is extended to derive the equations of motion of the plates using Navier's double trigonometric series, a closed-form solution is obtained; the primary conclusion is that simple solution is obtained with good results accuracy when compared with previously published results, and the natural frequency will differ depending on, environment temperature, thickness ratio, and lamination angle, as well as the aspect ratio of the plate.