• Title/Summary/Keyword: reducible

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감축 불가능한 유향그래프로부터 지배자 트리를 구성하기 위한 효과적인 알고리즘 (An Effective Algorithm for Constructing the Dominator Tree from Irreducible Directed Graphs)

  • 이대식;심손권;안희학
    • 한국정보처리학회논문지
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    • 제7권8호
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    • pp.2536-2542
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    • 2000
  • 지배자 트리란 유향그래프에서 지배관계를 트리로 표현한 것이다. 임의의 유향그래프로부터 지배자 트리를 구성하기 위한 효과적인 알고리즘을 제시한다. 감축 가능한 흐름그래프는 지배자 계산을 한 후 지배자 트리로 감축된다. 감축 불가능한 흐름그래프는 정보 테이블의 연결가지 정보를 이용하여 지배자 연결그래프로 구성된다. 지배자 연결그래프에서 지배자 트리로 감축하기 위하여 효과적인 순차감축 알고리즘과 지연감축 알고리즘을 제안한다.

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FACTORIZATION OF CERTAIN SELF-MAPS OF PRODUCT SPACES

  • Jun, Sangwoo;Lee, Kee Young
    • 대한수학회지
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    • 제54권4호
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    • pp.1231-1242
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    • 2017
  • In this paper, we show that, under some conditions, self-maps of product spaces can be represented by the composition of two specific self-maps if their induced homomorphism on the i-th homotopy group is an automorphism for all i in some section of positive integers. As an application, we obtain closeness numbers of several product spaces.

NOTE ON THE DECOMPOSITION OF STATES

  • Hyeon, Donghoon;Kim, Jaekwang
    • 대한수학회보
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    • 제55권4호
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    • pp.1221-1230
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    • 2018
  • We derive a sharp decomposition formula for the state polytope of the Hilbert point and the Hilbert-Mumford index of reducible varieties by using the decomposition of characters and basic convex geometry. This proof captures the essence of the decomposition of the state polytopes in general, and considerably simplifies an earlier proof by the authors which uses a careful analysis of initial ideals of reducible varieties.

COMPOSITION OF BINOMIAL POLYNOMIAL

  • Choi, Eun-Mi
    • 대한수학회논문집
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    • 제22권2호
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    • pp.183-194
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    • 2007
  • For an irreducible binomial polynomial $f(x)=x^n-b{\in}K[x]$ with a field K, we ask when does the mth iteration $f_m$ is irreducible but $m+1th\;f_{m+1}$ is reducible over K. Let S(n, m) be the set of b's such that $f_m$ is irreducible but $f_{m+1}$ is reducible over K. We investigate the set S(n, m) by taking K as the rational number field.

On Semi C-Reducibility of General (α, β) Finsler Metrics

  • Tiwari, Bankteshwar;Gangopadhyay, Ranadip;Prajapati, Ghanashyam Kr.
    • Kyungpook Mathematical Journal
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    • 제59권2호
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    • pp.353-362
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    • 2019
  • In this paper, we study general (${\alpha}$, ${\beta}$) Finsler metrics and prove that every general (${\alpha}$, ${\beta}$)-metric is semi C-reducible but not C2-like. As a consequence of this result we prove that every general (${\alpha}$, ${\beta}$)-metric satisfying the Ricci flow equation is Einstein.

CONFORMAL TRANSFORMATION OF LOCALLY DUALLY FLAT FINSLER METRICS

  • Ghasemnezhad, Laya;Rezaei, Bahman
    • 대한수학회보
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    • 제56권2호
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    • pp.407-418
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    • 2019
  • In this paper, we study conformal transformations between special class of Finsler metrics named C-reducible metrics. This class includes Randers metrics in the form $F={\alpha}+{\beta}$ and Kropina metric in the form $F={\frac{{\alpha}^2}{\beta}}$. We prove that every conformal transformation between locally dually flat Randers metrics must be homothetic and also every conformal transformation between locally dually flat Kropina metrics must be homothetic.

THE MAIN COMPONENT OF A REDUCIBLE HILBERT CURVE OF CONIC FIBRATIONS

  • Fania, Maria Lucia;Lanteri, Antonio
    • 대한수학회지
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    • 제58권5호
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    • pp.1211-1226
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    • 2021
  • The study of reducible Hilbert curves of conic fibrations over a smooth surface is carried on in this paper and the question of when the main component is itself the Hilbert curve of some ℚ-polarized surface is dealt with. Special attention is paid to the polynomial defining the canonical equation of the Hilbert curve.

Revealing Strong Metal Support Interaction during CO Oxidation with Metal Nanoparticle on Reducible Oxide Substrates

  • Park, Dahee;Kim, Sun Mi;Qadir, Kamran;Park, Jeong Young
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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    • pp.264-264
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    • 2013
  • Strong metal-support interaction effect is an important issue in determining the catalytic ac-tivity for heterogeneous catalysis. In this study, we investigated the support effect and the role of organic capping layers of two-dimensional Pt nanocatalysts on reducible metal oxide supports under the CO oxidation. Several reducible metal oxide supports including CeO2, Nb2O5, and TiO2 thin films were prepared via sol-gel techniques. The structure, chemical state and optical property were characterized using XRD, XPS, TEM, SEM, and UV-VIS spectrometer. We found that the reducible metal oxide supports have a homogeneous thin thickness and crystalline structure after annealing at high temperature showing the different optical band gap energy. Langmuir-Blodgett technique and arc plasma deposition process were employed to ob-tain Pt nanoparticle arrays with capping and without capping layers, respectively on the oxide support to assess the role of the supports and capping layers on the catalytic activity of Pt catalysts under the CO oxidation. The catalytic performance of CO oxidation over Pt supported on metal oxide thin films under oxidizing reaction conditions (40 Torr CO and 100 Torr O2) was tested. The results show that the catalytic activity significantly depends on the metal oxide support and organic capping layers of Pt nanoparticles, revealing the strong metal-support interaction on these nanocatalysts systems.

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