• Title/Summary/Keyword: triangular graphs

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SOME PROBLEMS AND RESULTS ON CIRCUIT GRAPHS AND TRIANGULAR GRAPHS

  • Jung, Hwan-Ok
    • Journal of applied mathematics & informatics
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    • v.26 no.3_4
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    • pp.531-540
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    • 2008
  • We discuss the decomposition problems on circuit graphs and triangular graphs, and show how they can be applied to obtain results on spanning trees or hamiltonian cycles. We also prove that every circuit graph containing no separating 3-cycles can be extended by adding new edges to a triangular graph containing no separating 3-cycles.

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DIFFERENCE CORDIALITY OF SOME SNAKE GRAPHS

  • Ponraj, R.;Narayanan, S. Sathish
    • Journal of applied mathematics & informatics
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    • v.32 no.3_4
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    • pp.377-387
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    • 2014
  • Let G be a (p, q) graph. Let f be a map from V (G) to {1, 2, ${\ldots}$, p}. For each edge uv, assign the label ${\mid}f(u)-f(\nu){\mid}$. f is called a difference cordial labeling if f is a one to one map and ${\mid}e_f(0)-e_f(1){\mid}{\leq}1$ where $e_f(1)$ and $e_f(0)$ denote the number of edges labeled with 1 and not labeled with 1 respectively. A graph with admits a difference cordial labeling is called a difference cordial graph. In this paper, we investigate the difference cordial labeling behavior of triangular snake, Quadrilateral snake, double triangular snake, double quadrilateral snake and alternate snakes.

PAIR DIFFERENCE CORDIALITY OF CERTAIN SUBDIVISION GRAPHS

  • R. PONRAJ;A. GAYATHRI;S. SOMASUNDARAM
    • Journal of applied mathematics & informatics
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    • v.42 no.1
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    • pp.1-14
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    • 2024
  • Let G = (V, E) be a (p, q) graph. Define $$\begin{cases}\frac{p}{2},\:if\:p\:is\:even\\\frac{p-1}{2},\:if\:p\:is\:odd\end{cases}$$ and L = {±1, ±2, ±3, ···, ±ρ} called the set of labels. Consider a mapping f : V → L by assigning different labels in L to the different elements of V when p is even and different labels in L to p - 1 elements of V and repeating a label for the remaining one vertex when p is odd.The labeling as defined above is said to be a pair difference cordial labeling if for each edge uv of G there exists a labeling |f(u) - f(v)| such that |Δf1 - Δfc1| ≤ 1, where Δf1 and Δfc1 respectively denote the number of edges labeled with 1 and number of edges not labeled with 1. A graph G for which there exists a pair difference cordial labeling is called a pair difference cordial graph. In this paper we investigate the pair difference cordial labeling behavior of subdivision of some graphs.

INTERSECTION GRAPH에 관하여

  • Kim Yuon Sik
    • The Mathematical Education
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    • v.13 no.2
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    • pp.6-10
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    • 1974
  • We consider 'ordinary' graphs: that is, finite undirected graphs with no loops or multiple edges. An intersection representation of a graph G is a function r from V(G), the set of vertices of G, into a family of sets S such that distinct points $\chi$$_{\alpha}$ and $\chi$$_{\beta}$/ of V(G) are. neighbors in G precisely when ${\gamma}$($\chi$$_{\alpha}$)∩${\gamma}$($\chi$$_{\beta}$/)$\neq$ø, A graph G is a rigid circuit grouph if every cycle in G has at least one triangular chord in G. In this paper we consider the main theorem; A graph G has an intersection representation by arcs on an acyclic graph if and only if is a normal rigid circuit graph.uit graph.d circuit graph.uit graph.

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SOME 4-TOTAL PRIME CORDIAL LABELING OF GRAPHS

  • PONRAJ, R.;MARUTHAMANI, J.;KALA, R.
    • Journal of applied mathematics & informatics
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    • v.37 no.1_2
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    • pp.149-156
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    • 2019
  • Let G be a (p, q) graph. Let $f:V(G){\rightarrow}\{1,2,{\ldots},k\}$ be a map where $k{\in}{\mathbb{N}}$ and k > 1. For each edge uv, assign the label gcd(f(u), f(v)). f is called k-Total prime cordial labeling of G if ${\mid}t_f(i)-t_f(j){\mid}{\leq}1$, $i,j{\in}\{1,2,{\ldots},k\}$ where $t_f$(x) denotes the total number of vertices and the edges labelled with x. A graph with a k-total prime cordial labeling is called k-total prime cordial graph. In this paper we investigate the 4-total prime cordial labeling of some graphs.

Investigation of Asymmetric Aspherical Triangular Prism Optical System for Video Information Display (영상정보디스플레이용 비대칭 비구면 삼각 프리즘 광학계 연구)

  • Youn, Gap-Suck;Yoo, Kyung-Sun;Hyun, Dong-Hoon
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.23 no.6
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    • pp.590-595
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    • 2014
  • We have investigated anamorphic prism lenses with distortions of 0.3-0.5%. We designed the plastic triangular lens and confirmed the minimum resolution using MTF graphs. Also we confirmed that the SVGA optical system can realize a resolution of $864{\times}648$ 56 megapixels. A distortion of about 0.5% aberration appears in the maximum field, and a finite beam aberration of about $15{\mu}m$ is confirmed. We made a mold based on the design data and completed the prism lens through exodus molding. We confirmed the shape error (< $30{\mu}m$) and surface roughness (> 40 nm) of the three sides. We made the video-information-display prototype glasses using prism lens by measuring the performance, we determined the distortion aberration (0.3%) and SVGA resolution. Our approach will enable fabrication of a portable large-screen display device for glasses and sunglasses for the domestic market and, after 2015, for the world market.

ON PAIR MEAN CORDIAL GRAPHS

  • R. PONRAJ;S. PRABHU
    • Journal of Applied and Pure Mathematics
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    • v.5 no.3_4
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    • pp.237-253
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    • 2023
  • Let a graph G = (V, E) be a (p, q) graph. Define $${\rho}=\{\array{{\frac{p}{2}} & \;\;p\text{ is even} \\ {\frac{p-1}{2}} & \;\;p\text{ is odd,}$$ and M = {±1, ±2, … ± ρ} called the set of labels. Consider a mapping λ : V → M by assigning different labels in M to the different elements of V when p is even and different labels in M to p - 1 elements of V and repeating a label for the remaining one vertex when p is odd. The labeling as defined above is said to be a pair mean cordial labeling if for each edge uv of G, there exists a labeling ${\frac{{\lambda}(u)+{\lambda}(v)}{2}}$ if λ(u) + λ(v) is even and ${\frac{{\lambda}(u)+{\lambda}(v)+1}{2}}$ if λ(u) + λ(v) is odd such that ${\mid}{\bar{{\mathbb{S}}}}_{\lambda}{_1}-{\bar{{\mathbb{S}}}}_{{\lambda}^c_1}{\mid}{\leq}1$ where ${\bar{{\mathbb{S}}}}_{\lambda}{_1}$ and ${\bar{{\mathbb{S}}}}_{{\lambda}^c_1}$ respectively denote the number of edges labeled with 1 and the number of edges not labeled with 1. A graph G for which there exists a pair mean cordial labeling is called a pair mean cordial graph. In this paper, we investigate the pair mean cordial labeling behavior of few graphs including the closed helm graph, web graph, jewel graph, sunflower graph, flower graph, tadpole graph, dumbbell graph, umbrella graph, butterfly graph, jelly fish, triangular book graph, quadrilateral book graph.

Efficient Sampling of Graph Signals with Reduced Complexity (저 복잡도를 갖는 효율적인 그래프 신호의 샘플링 알고리즘)

  • Kim, Yoon Hak
    • The Journal of the Korea institute of electronic communication sciences
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    • v.17 no.2
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    • pp.367-374
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    • 2022
  • A sampling set selection algorithm is proposed to reconstruct original graph signals from the sampled signals generated on the nodes in the sampling set. Instead of directly minimizing the reconstruction error, we focus on minimizing the upper bound on the reconstruction error to reduce the algorithm complexity. The metric is manipulated by using QR factorization to produce the upper triangular matrix and the analytic result is presented to enable a greedy selection of the next nodes at iterations by using the diagonal entries of the upper triangular matrix, leading to an efficient sampling process with reduced complexity. We run experiments for various graphs to demonstrate a competitive reconstruction performance of the proposed algorithm while offering the execution time about 3.5 times faster than one of the previous selection methods.

ON 4-TOTAL MEAN CORDIAL GRAPHS

  • PONRAJ, R.;SUBBULAKSHMI, S.;SOMASUNDARAM, S.
    • Journal of applied mathematics & informatics
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    • v.39 no.3_4
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    • pp.497-506
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    • 2021
  • Let G be a graph. Let f : V (G) → {0, 1, …, k - 1} be a function where k ∈ ℕ and k > 1. For each edge uv, assign the label $f(uv)={\lceil}{\frac{f(u)+f(v)}{2}}{\rceil}$. f is called k-total mean cordial labeling of G if ${\mid}t_{mf}(i)-t_{mf}(j){\mid}{\leq}1$, for all i, j ∈ {0, 1, …, k - 1}, where tmf (x) denotes the total number of vertices and edges labelled with x, x ∈ {0, 1, …, k-1}. A graph with admit a k-total mean cordial labeling is called k-total mean cordial graph.

Cross-sectional analysis of arbitrary sections allowing for residual stresses

  • Li, Tian-Ji;Liu, Si-Wei;Chan, Siu-Lai
    • Steel and Composite Structures
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    • v.18 no.4
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    • pp.985-1000
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    • 2015
  • The method of cross-section analysis for different sections in a structural frame has been widely investigated since the 1960s for determination of sectional capacities of beam-columns. Many hand-calculated equations and design graphs were proposed for the specific shape and type of sections in pre-computer age decades ago. In design of many practical sections, these equations may be uneconomical and inapplicable for sections with irregular shapes, leading to the high construction cost or inadequate safety. This paper not only proposes a versatile numerical procedure for sectional analysis of beam-columns, but also suggests a method to account for residual stress and geometric imperfections separately and the approach is applied to design of high strength steels requiring axial force-moment interaction for advanced analysis or direct analysis. A cross-section analysis technique that provides interaction curves of arbitrary welded sections with consideration of the effects of residual stress by meshing the entire section into small triangular fibers is formulated. In this study, two doubly symmetric sections (box-section and H-section) fabricated by high-strength steel is utilized to validate the accuracy and efficiency of the proposed method against a hand-calculation procedure. The effects of residual stress are mostly not considered explicitly in previous works and they are considered in an explicit manner in this paper which further discusses the basis of the yield surface theory for design of structures made of high strength steels.