• Title/Summary/Keyword: D-compact space

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ANALYTIC TORSION FOR HOLOMORPHIC VECTOR BUNDLES

  • Kim, Hong-Jong
    • Communications of the Korean Mathematical Society
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    • v.9 no.3
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    • pp.669-670
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    • 1994
  • Let $E \to M$ be a hermitian holomorphic vector bundle over a compact (complex) hermitian manifold M of complex dimension n, and let $$ d"_p(E) : 0 \to A^{p,0}(E) \to A^{p,1}(E) \to \cdots \to A^{p,n}(E) \to 0$$ be the Dolbeault complex. Then $A^{p,q}(E)$ become a prehibert space so that the formal adjoint $\delta"$ of $d"$ and the "Laplacian" $\Delta" = \delta" d" + d" \delta"$ are defined.quot; d" + d" \delta"$ are defined.;$ are defined.

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COMPACT OPERATOR RELATED WITH POISSON-SZEGö INTEGRAL

  • Yang, Gye Tak;Choi, Ki Seong
    • Journal of the Chungcheong Mathematical Society
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    • v.20 no.3
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    • pp.333-342
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    • 2007
  • Suppose that ${\mu}$ is a finite positive Borel measure on the unit ball $B{\subset}C^n$. The boundary of B is the unit sphere $S=\{z:{\mid}z{\mid}=1\}$. Let ${\sigma}$ be the rotation-invariant measure on S such that ${\sigma}(S)=1$. In this paper, we will show that if $sup_{{\zeta}{\in}S}\;{\int}_{B}\;P(z,{\zeta})d{\mu}(z)$<${\infty}$ where $P(z,{\zeta})$ is the Poission-Szeg$\ddot{o}$ kernel for B, then ${\mu}$ is a Carleson measure. We will also show that if $sup_{{\zeta}{\in}S}\;{\int}_{B}\;P(z,{\zeta})d{\mu}(z)$<${\infty}$, then the operator T such that T(f) = P[f] is compact as a mapping from $L^p(\sigma)$ into $L^p(B,d{\mu})$.

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ISOMETRIES WITH SMALL BOUND ON $C^1$(X) SPACES

  • Jun, Kil-Woung;Lee, Yang-Hi
    • Bulletin of the Korean Mathematical Society
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    • v.32 no.1
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    • pp.85-91
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    • 1995
  • For a locally compact Hausdorff space, we denote by $C_0(X)$ the Banach space of all continuous complex valued functions defined on X which vanish at infinity, equipped with the usual sup norm. In case X is compact, we write C(X) instead of $C_0(X)$. A well-known Banach-Stone theorem states that the existence of an isometry between the function spaces $C_0(X)$ and $C_0(Y)$ implies X and Y are homemorphic. D. Amir [1] and M. Cambern [2] independently generalized this theorem by proving that if $C_0(X)$ and $C_0(Y)$ are isomorphic under an isomorphism T satisfying $\left\$\mid$ T \right\$\mid$ \left\$\mid$ T^1 \right\$\mid$ < 2$, then X and Y must also be homeomorphic.

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ON A CHARACTERIZATION OF ROUND SPHERES

  • Onat, Leyla
    • Bulletin of the Korean Mathematical Society
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    • v.39 no.4
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    • pp.681-685
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    • 2002
  • It is shown that, an immersion of n-dimensional compact manifold without boundary into (n + 1)-dimensional Euclidean space, hyperbolic space or the open half spheres, is a totally umbilic immersion if for some r, r =2, 3, …, n the r-th mean curvature Hr does not vanish and there are nonnegative constants $C_1$, $C_2$, …, $C_{r}$ such that (equation omitted)d)

STATIONARY SOLUTIONS FOR ITERATED FUNCTION SYSTEMS CONTROLLED BY STATIONARY PROCESSES

  • Lee, O.;Shin, D.W.
    • Journal of the Korean Mathematical Society
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    • v.36 no.4
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    • pp.737-746
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    • 1999
  • We consider a class of discrete parameter processes on a locally compact Banach space S arising from successive compositions of strictly stationary random maps with state space C(S,S), where C(S,S) is the collection of continuous functions on S into itself. Sufficient conditions for stationary solutions are found. Existence of pth moments and convergence of empirical distributions for trajectories are proved.

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SELECTION THEOREMS WITH n-CONNECTDENESS

  • In-Sook Kim
    • Journal of the Korean Mathematical Society
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    • v.35 no.1
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    • pp.165-175
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    • 1998
  • We give a generalization of the selection theorem of Ben-El-Mechaiekh and Oudadess to complete LD-metric spaces with the aid of the notion of n-connectedness. Our new selection theorem is used to obtain new results of fixed points and coincidence points for compact lower semicontinuous set-valued maps with closed values consisting of D-sets in a complete LD-metric space.

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A Study on the Optimum Design of Plate-Fin Compact Sensible Heat Exchanger for the Heat Recovery of Exhaust Gas (배기열(排氣熱) 회수용(回收用) 평판(平板) - 휜형(形) 밀집형(密集形) 현열(顯熱) 열교환기(熱交換器)의 최적설계(最適設計)에 관한 연구(硏究))

  • Choi, Y.D.;Park, S.D.;Woo, J.S.;Tae, C.S.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.2 no.2
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    • pp.85-98
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    • 1990
  • Method of optimum design of a compact sensible plate-fin heat exchanger for the heat recovery of exhaust gas from the air conditioning space was developed in consideration of the econamics of investment cost and profit according to the installation of heat exchanges. In the counterflow heat exchanger, the frontal area was fixed and the length of heat exchanger was optimized in order to maximize the net gain according to the setting of the heat exchanger. In the cross flow heat exchanger, the size of the exchanger was also optimized to maximize the net gain.

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ON $\varepsilon$-BIRKHOFF ORTHOGONALITY AND $\varepsilon$-NEAR BEST APPROXIMATION

  • Sharma, Meenu;Narang, T.D.
    • The Pure and Applied Mathematics
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    • v.8 no.2
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    • pp.153-162
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    • 2001
  • In this Paper, the notion of $\varepsilon$-Birkhoff orthogonality introduced by Dragomir [An. Univ. Timisoara Ser. Stiint. Mat. 29(1991), no. 1, 51-58] in normed linear spaces has been extended to metric linear spaces and a decomposition theorem has been proved. Some results of Kainen, Kurkova and Vogt [J. Approx. Theory 105 (2000), no. 2, 252-262] proved on e-near best approximation in normed linear spaces have also been extended to metric linear spaces. It is shown that if (X, d) is a convex metric linear space which is pseudo strictly convex and M a boundedly compact closed subset of X such that for each $\varepsilon$>0 there exists a continuous $\varepsilon$-near best approximation $\phi$ : X → M of X by M then M is a chebyshev set .

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Particle capture by radiation drag around a highly luminous compact stars

  • Oh, Jae Sok;Park, Chan;Kim, Hongsu
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.1
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    • pp.77.2-77.2
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    • 2013
  • xIn the present work, we explored the effect of the radiation on the effective impact parameter for capture in a fully general relativistic manner. To summarize our results, evidently due to the radiation drag (the Poynting-Robertson effect), critical impact parameter of point particle gets larger by the factor of two, thus, the effective cross section of the luminous relativistic star becomes 4 times larger than that of the star without radiation emission. In addition, the finite size effect of the star adds up to this growth of the effective cross section.

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