• Title/Summary/Keyword: Riemann

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RIEMANN-STIELTJES INTEGRATION OF FUNCTIONS OF $\textsc{k}{\phi}-BOUNDED$ VARIATIONS

  • JAEKEUN PARK
    • Journal of applied mathematics & informatics
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    • v.4 no.2
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    • pp.545-553
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    • 1997
  • By using the decreasing rearrangement of nonoverlapping subintervals of a closed bounded intervals and L.C.young's series for two ø-sequences we obtain some results concerning Riemann-Stieltijes integrals of functions of $\textsc{k}{\phi}-bounded$ variations.

THE RIEMANN PROBLEM FOR A SYSTEM OF CONSERVATION LAWS OF MIXED TYPE (II)

  • Lee, Choon-Ho
    • Communications of the Korean Mathematical Society
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    • v.13 no.1
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    • pp.37-59
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    • 1998
  • We prove that solutions $u^\epsilon$ for the mixed hyperbolic-elliptic system of conservation laws with the viscosity term are total variation bounded uniformly in $\epsilon$ and that the solution $u^\epsilon$ converges to the solution for the mixed hyperbolic-elliptic Riemann problem as $\epsilon \to 0$.

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ABASIS OF THE SPACE OF MEROMORPHIC DIFFERENTIALS ON RIEMANN SURFACES

  • Lee, Man-Keun
    • Communications of the Korean Mathematical Society
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    • v.14 no.1
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    • pp.13-18
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    • 1999
  • In this paper, we compute a basis of the space of meromorphic differentials on a Riemann surface, holomorphic away from two fixed points. This basis consists of the differentials which have the expected zero or pole order at the two fixed points.

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TORQUES AND RIEMANN'S MINIMAL SURFACES

  • Jin, Sun Sook
    • Journal of the Chungcheong Mathematical Society
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    • v.19 no.3
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    • pp.219-224
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    • 2006
  • In this article, we prove that a properly embedded minimal surface in $R^3$ of genus zero must be one of Riemann's minimal examples if outside of a solid cylinder it is the union of planar ends with the same torques at all integer heights.

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Convergence and the Riemann hypothesis

  • Lee, Jung-Seob
    • Communications of the Korean Mathematical Society
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    • v.11 no.1
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    • pp.57-62
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    • 1996
  • For $1 < p \leq 2$ it is shown that a certain sequence of functions converges to -1 in $L^{p-\varepsilon}(0, 1)$ for any small $\varepsilon > 0$ if and only if the Riemann zeta function satisfies $\zeta(s) \neq 0$ for $\sigma = Re s > 1/p$.

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THE GENERALIZED RIEMANN PROBLEM FOR FIRST ORDER QUASILINEAR HYPERBOLIC SYSTEMS OF CONSERVATION LAWS I

  • Chen, Shouxin;Huang, Decheng;Han, Xiaosen
    • Bulletin of the Korean Mathematical Society
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    • v.46 no.3
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    • pp.409-434
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    • 2009
  • In this paper, we consider a generalized Riemann problem of the first order hyperbolic conservation laws. For the case that excludes the centered wave, we prove that the generalized Riemann problem admits a unique piecewise smooth solution u = u(t, x), and this solution has a structure similar to the similarity solution u = $U{(\frac{x}{t})}$ of the correspondin Riemann problem in the neighborhood of the origin provided that the coefficients of the system and the initial conditions are sufficiently smooth.

EXACT RIEMANN SOLVER FOR THE AIR-WATER TWO-PHASE SHOCK TUBE PROBLEMS (공기-물 이상매질 충격파관 문제에 대한 정확한 Riemann 해법)

  • Yeom, G.S.;Chang, K.S.
    • 한국전산유체공학회:학술대회논문집
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    • 2010.05a
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    • pp.365-367
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    • 2010
  • In this paper, we presented the exact Riemann solver for the air-water two-phase shock tube problems where the strength of the propagated sock wave is moderately weak. The shock tube has a diaphragm in the middle which separates water medium in the left and air medium in the right. By rupturing the diaphragm, various waves such as rarefaction wave, shock wave and contact discontinuity are propagated into water and air. Both fluids are treated as compressible, with the linearized equations of state. We used the isentropic relations for the air and water assuming a weak shock wave. We solved the shock tube problem considering a high pressure in the water and a low pressure in the air. The numerical results cleary showed a left-traveling rarefaction wave in the water, a right-traveling shock wave in the air, and the right-traveling material interface.

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