Gen Nakamura

Quantitative uniqueness for second order elliptic operators with strongly singular coefficients (2008)

Lin, Ching-Lung, Nakamura, Gen, Wang, Jenn-Nan

In this paper we study the local behavior of a solution to second order elliptic operators with sharp singular coefficients in lower order terms. One of the main results is the bound on the vanishing...

Unique continuation for the elastic transversally isotropic dynamical systems and its application. (2007)

Lin, Ching-Lung, Nakamura, Gen, Sini, Mourad

In this paper, we prove the unique continuation property of the solution for the elastic transversally isotropic dynamical systems with smooth coefficents satisfying some conditions and apply it to...

Unique continuation for the elastic transversally isotropic dynamical systems and its application. (2007)

Lin, Ching-Lung, Nakamura, Gen, Sini, Mourad

In this paper, we prove the unique continuation property of the solution for the elastic transversally isotropic dynamical systems with smooth coefficents satisfying some conditions and apply it to...

The no-response approach and its relation to non-iterative methods for the inverse scattering (2007)

Honda, Naofumi, Nakamura, Gen, Potthast, Roland, Sini, Mourad

This paper addresses the inverse obstacle scattering problem. In the recent years several non-iterative methods have been proposed to reconstruct obstacles (penetrable or impenetrable) from near or...

Obstacle and boundary determination from scattering data (2007)

Nakamura, Gen, Sini, Mourad

In this paper, we are concerned with the identification of complex obstacles from the scattering data for the acoustic problem. The complex obstacle is characterized by its shape and the boundary...

Reconstruction of the shape and surface impedance from acoustic scattering data for arbitrary cylinder (2007)

Liu, Jijun, Nakamura, Gen, Sini, Mourad

The inverse scattering for an obstacle $ D\subset R^2$ with mixed boundary condition can be considered as a prototype for radar detection of complex obstacles with coated and non-coated parts of the...

A variational approach for an inverse dynamical problem for composite beams (2007)

Morassi, Antonino, Nakamura, Gen, Shirota, Kenji, Sini, Mourad

This paper deals with a problem of nondestructive testing for a composite system formed by the connection of a steel beam and a reinforced concrete beam. The small vibrations of the composite beam...

A variational approach for an inverse dynamical problem for composite beams (2007)

Morassi, Antonino, Nakamura, Gen, Shirota, Kenji, Sini, Mourad

This paper deals with a problem of nondestructive testing for a composite system formed by the connection of a steel beam and a reinforced concrete beam. The small vibrations of the composite beam...

Reconstruction of the shape and surface impedance from acoustic scattering data for arbitrary cylinder (2007)

Liu, Jijun, Nakamura, Gen, Sini, Mourad

The inverse scattering for an obstacle $ D\subset R^2$ with mixed boundary condition can be considered as a prototype for radar detection of complex obstacles with coated and non-coated parts of the...

Obstacle and boundary determination from scattering data (2007)

Nakamura, Gen, Sini, Mourad

In this paper, we are concerned with the identification of complex obstacles from the scattering data for the acoustic problem. The complex obstacle is characterized by its shape and the boundary...

The no-response approach and its relation to non-iterative methods for the inverse scattering (2007)

Honda, Naofumi, Nakamura, Gen, Potthast, Roland, Sini, Mourad

This paper addresses the inverse obstacle scattering problem. In the recent years several non-iterative methods have been proposed to reconstruct obstacles (penetrable or impenetrable) from near or...

Unique continuation for the transversally isotropic dynamical systems and its application (2005)

Lin, Ching-Lung, Nakamura, Gen, Sini, Mourad

In this paper we prove the unique continuation property of the solution for the transversally isotropic dynamical systems with smooth coefficients satisfying some conditions and apply it to extending...

Reconstruction of Inclusions for the Inverse Boundary Value Problem of Non-stationary Heat Equation (2005)

Daido, Yuki, Kang, Hyeonbae, Nakamura, Gen

An inverse problem for identifying an inclusion inside an isotropic, homogeneous heat conductive medium is considered. The shape of inclusion can change depending on time. For the one space...

Recovery of Boundaries and Types for Multiple Obstacles from the Far-field Pattern (2005)

Cheng, Jin, Liu, Jijun, Nakamura, Gen

We consider an inverse scattering problem for multiple obstacles $D=\cup_{j=1}^ND_j\subset {R}^3$ with different types of boundary of $D_j$. By constructing an indicator function from the far-field...

Numerical differentiation of the second order derivative of functions with several variables (2005)

Nakamura, Gen, Wang, Shengzhang, Wang, Yanbo

We propose a regularized optimization problem for computing numerical di®erentiation for the second order deriva- tive for functions with two variables from the noisy values of the function at...

Numerical differentiation of the second order derivative of functions with several variables (2005)

Nakamura, Gen, Wang, Shengzhang, Wang, Yanbo

We propose a regularized optimization problem for computing numerical di®erentiation for the second order deriva- tive for functions with two variables from the noisy values of the function at...

Recovery of Boundaries and Types for Multiple Obstacles from the Far-field Pattern (2005)

Cheng, Jin, Liu, Jijun, Nakamura, Gen

We consider an inverse scattering problem for multiple obstacles $D=\cup_{j=1}^ND_j\subset {R}^3$ with different types of boundary of $D_j$. By constructing an indicator function from the far-field...

Reconstruction of Inclusions for the Inverse Boundary Value Problem of Non-stationary Heat Equation (2005)

Daido, Yuki, Kang, Hyeonbae, Nakamura, Gen

An inverse problem for identifying an inclusion inside an isotropic, homogeneous heat conductive medium is considered. The shape of inclusion can change depending on time. For the one space...

Unique continuation for the transversally isotropic dynamical systems and its application (2005)

Lin, Ching-Lung, Nakamura, Gen, Sini, Mourad

In this paper we prove the unique continuation property of the solution for the transversally isotropic dynamical systems with smooth coefficients satisfying some conditions and apply it to extending...

The convergence proof of the no-response test for localizing an inclusion (2004)

Nakamura, Gen, Potthast, Roland, Sini, Mourad

In this paper, we use the no-response test idea, introduced in ([L-P],[P1]) for the inverse obstacle problem, to identify the interface of the discontinuity of the coefficient \gamma of the equation...

An inverse dynamical problem for connected beams (2004)

Morassi, Antonino, Nakamura, Gen, Sini, Mourad

This paper deals with a dynamical inverse problem for a composite beam formed by two connected beams. The vibrations of the composite beam are governed by a differential system where a coupling takes...

An inverse dynamical problem for connected beams (2004)

Morassi, Antonino, Nakamura, Gen, Sini, Mourad

This paper deals with a dynamical inverse problem for a composite beam formed by two connected beams. The vibrations of the composite beam are governed by a differential system where a coupling takes...

The convergence proof of the no-response test for localizing an inclusion (2004)

Nakamura, Gen, Potthast, Roland, Sini, Mourad

In this paper, we use the no-response test idea, introduced in ([L-P],[P1]) for the inverse obstacle problem, to identify the interface of the discontinuity of the coefficient \gamma of the equation...

Remarks on the Inverse Scattering Problem for Ocean Acoustics (2003)

Nakamura, Gen, Sini, Mourad

We propose two new formulations of inverse scattering problems for ocean acoustics and give the reconstruction formula for them. Both of them use near field data instead of the far field pattern of...

Remarks on the Inverse Scattering Problem for Ocean Acoustics (2003)

Nakamura, Gen, Sini, Mourad

We propose two new formulations of inverse scattering problems for ocean acoustics and give the reconstruction formula for them. Both of them use near field data instead of the far field pattern of...

Identification of nonlinearity in conductivity equation via Dirichlet-to-Neumann map (2002)

Kang, Hyeonbae, Nakamura, Gen

We prove that the linear term and quadratic nonlinear term entering a nonlinear elliptic equation of divergence type can be uniquely identified by the Dirichlet to Neuman map. The unique...

Phylogenetic Position of Blastocystis hominis and of Stramenopiles Inferred from Multiple Molecular Sequence Data (2002)

NOBUKO ARISUE, TETSUO HASHIMOTO, HISAO YOSHIKAWA, YOSHIHIRO NAKAMURA, GEN NAKAMURA, FUMINORI NAKAMURA, ...

Blastocystis hominis, a parasite of the human intestine, has recently been positioned within stramenopiles by the small subunit rRNA phylogeny. To further confirm its phylogenetic position using...