Overview and details of the sessions of this conference. Please select a date or location to show only sessions at that day or location. Please select a single session for detailed view (with abstracts and downloads if available).
On the identification of small anomaly via MUSIC algorithm without background information
Won-Kwang Park
Kookmin University, Korea, Republic of (South Korea)
MUltiple SIgnal Classification (MUSIC) is a promising non-iterative technique for identifying small anomaly in microwave imaging. For a successful application, accurate values of permittivity, permeability, and conductivity of the background must be known. If one of these values is unknown, inaccurate location will inevitably retrieved by using the MUSIC. To explain this phenomenon, we investigate the structure of the imaging function of MUSIC by establishing a relationship with an infinite series of the Bessel functions of integer order, antenna arrangement, and applied values of permittivity, permeability, and conductivity. The revealed structure explains the theoretical reason why inaccurate location of anomaly is retrieved. Simulation results with synthetic data are illustrated to support the theoretical result.
[1] W.-K. Park. Application of MUSIC algorithm in real-world microwave imaging of unknown anomalies from scattering matrix, Mech. Syst. Signal Proc. 153: Article No. 107501, 2021.
[2] R. Solimene, G. Ruvio, A. Dell'Aversano, A. Cuccaro, Max J. Ammann, R. Pierri. Detecting point-like sources of unknown frequency spectra, Prog. Electromagn. Res. B 50: 347-364, 2013.
Construction of inclusions with vanishing generalized polarization tensors by imperfect interfaces
Doosung Choi1, Mikyoung Lim2
1Louisiana State University, United States of America; 2Korea Advanced Institute of Science and Technology, Republic of Korea
We address this question and provide a new construction scheme to find GPT-vanishing structures by imperfect interfaces. In particular, we construct GPT-vanishing structures of general shape with imperfect interfaces, where the inclusions have arbitrarily finite conductivity.
Spectral theory of surface plasmons in the nonlocal hydrodynamic Drude model
Hyundae Lee1, Matias Ruiz3, Sanhyeon Yu2
1Inha University, South Korea; 2Korea University, South Korea; 3University of Edinburgh, Scotland
We study surface plasmons, which are collective oscillations of electrons at metal-dielectric interfaces that can be excited by light. The local Drude model, which is the standard way to describe surface plasmons, ignores the spatial and quantum variations of the electron gas. These variations matter at the nanoscale and can change how metallic nanostructures interact with light. We use integral operator methods to investigate how the nonlocal hydrodynamic Drude model (HDM), which accounts for these variations, affects the spectral properties of surface plasmons in general shapes with smooth boundaries.
Numerical computation of Laplacian eigenvalues based on the layer potential formulation
Mikyoung Lim, Jiho Hong
Korea Advanced Institute of Science and Technology, Korea, Republic of (South Korea)
In this talk, we will present a numerical method that allows for the Laplacian eigenvalues of a planar, simply connected domain by only using the coefficients of the conformal mapping of the domain. We formulate the eigenvalue problems using the layer potential characterization and geometric density basis functions, resulting in an infinite dimensional matrix, where geometric density basis functions are associated with the conformal mapping of the domain. We will discuss how to compute the eigenvalues by using this infinite-dimensional matrix. Additionally, we will provide some convergence analysis for this approach based on the Gohberg-Sigal theory for operator-valued functions.
