Arathi Rani Santhamurthy
Bio: Arathi Rani Santhamurthy is an academic researcher from Indian Institute of Technology Madras. The author has contributed to research in topics: Absorption spectroscopy & Flash photolysis. The author has an hindex of 1, co-authored 1 publications receiving 2 citations.
TL;DR: In this paper, the authors used microwave dielectric absorption to study the excited triplet states formed by the laser flash photolysis and reported the triplet state lifetime and dipole moments of fluorenone and its derivatives.
Abstract: The technique of time resolved microwave dielectric absorption has been used to study the excited triplet states formed by the laser flash photolysis. The details of the experimental method and apparatus are discussed. The triplet state lifetimes and triplet state dipole moments of fluorenone and its derivatives are reported. The triplet state lifetime of fluorenone agrees with that obtained by optical absorption. The lifetime measurements with argon purging and with air equilibrated solution confirm the formation of triplet states. A marked increase in the triplet state dipole moment of fluorenone and its derivatives is observed and implies that their lowest triplet state is of (π, π * ) in nature.
05 May 2012
TL;DR: In this article, a 2D finite difference time domain (FDTD) was used to evaluate the forward problem and the inverse problem was solved via a Bayesian approach via a posterior distribution over the model parameters such as complex permittivity.
Abstract: : The motivation of this work is to quantify the degradation of aging electrical cables. The dielectric material parameter of insulation can be correlated with degradation. In this paper, the forward problem is posed as a microwave nondestructive evaluation (NDE) problem. A 2D finite difference time domain (FDTD) was used to evaluate the forward problem. The inverse problem is solved via a Bayesian approach. The Bayesian formulation describes the solution as a posterior distribution over the model parameters such as complex permittivity. Since there is no analytical solution for the posterior distribution, the Markov Chain Monte Carlo (MCMC) method is employed to numerically solve for it. The Metropolis-Hasting algorithm is used in particular. Results for computational experiments are demonstrated to show feasibility of this approach.
17 Oct 2011
TL;DR: In this paper, a stochastic inversion technique based on the Metropolis-Hasting algorithm was applied to the problem of quantitative nondestructive evaluation (QNDE) of material aging parameters.
Abstract: : The quantitative nondestructive evaluation (QNDE) of material aging parameters continues to be a very challenging problem. In our approach, we formulated a forward problem arising in specific micro guided wave test. A stochastic inversion technique based on the Metropolis-Hasting algorithm was applied to the problem. The feasibility and validity of the approach was demonstrated through computational experiments.