• 제목/요약/키워드: Dirichlet to Neumann map

검색결과 4건 처리시간 0.019초

UNIQUENESS OF IDENTIFYING THE CONVECTION TERM

  • Cheng, Jin;Gen Nakamura;Erkki Somersalo
    • 대한수학회논문집
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    • 제16권3호
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    • pp.405-413
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    • 2001
  • The inverse boundary value problem for the steady state heat equation with convection term is considered in a simply connected bounded domain with smooth boundary. Taking the Dirichlet to Neumann map which maps the temperature on the boundary to the that flux on the boundary as an observation data, the global uniqueness for identifying the convection term from the Dirichlet to Neumann map is proved.

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DIRECT DETERMINATION OF THE DERIVATIVES OF CONDUCTIVITY AT THE BOUNDARY FROM THE LOCALIZED DIRICHLET TO NEUMANN MAP

  • Gen-Nakamura;Kazumi-Tanuma
    • 대한수학회논문집
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    • 제16권3호
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    • pp.415-425
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    • 2001
  • We consider the problem of determining conductivity of the medium from the measurements of the electric potential on the boundary and the corresponding current flux across the boundary. We give a formula for reconstructing the conductivity and its normal derivative at the point of the boundary simultaneously from the localized Diichlet to Neumann map around that point.

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INTEGRAL REPRESENTATIONS IN ELECTRICAL IMPEDANCE TOMOGRAPHY USING BOUNDARY INTEGRAL OPERATORS

  • Kwon, Ki-Woon
    • 대한수학회지
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    • 제45권1호
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    • pp.97-119
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    • 2008
  • Electrical impedance tomography (EIT) problem with anisotropic anomalous region is formulated in a few different ways using boundary integral operators. The Frechet derivative of Neumann-to-Dirichlet map is computed also by using boundary integral operators and the boundary of the anomalous region is approximated by trigonometric expansion with Lagrangian basis. The numerical reconstruction is done in case that the conductivity of the anomalous region is isotropic.

A REMARK ON INVARIANCE OF QUANTUM MARKOV SEMIGROUPS

  • Choi, Ve-Ni;Ko, Chul-Ki
    • 대한수학회논문집
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    • 제23권1호
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    • pp.81-93
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    • 2008
  • In [3, 9], using the theory of noncommutative Dirichlet forms in the sense of Cipriani [6] and the symmetric embedding map, authors constructed the KMS-symmetric Markovian semigroup $\{S_t\}_{t{\geq}0}$ on a von Neumann algebra $\cal{M}$ with an admissible function f and an operator $x\;{\in}\;{\cal{M}}$. We give a sufficient and necessary condition for x so that the semigroup $\{S_t\}_{t{\geq}0}$ acts separately on diagonal and off-diagonal operators with respect to a basis and study some results.