The time domain Born approximation for ultrasonic scattering from volume flaws in an elastic medium is described. Results are given both for the direct and the inverse problem. The time domain picture leads to simple intuitive formulas which we illustrate by means of several simple examples. Particular emphasis is given to the front surface echo and its use in reconstructing the properties of t...

ticle provides a foundation for appreciating some of the key issues that arise in the computational aspects of ultrafast time-domain optics. Because temporal dispersion exists in all materials, it is fundamental to describing the optical field in material bodies when the field is pulsed, especially when the pulse is either ultrashort or ultrawideband. Temporal dispersion implies that the materi...

the ip3r calcium release channel has been simulated using a stochastic simulation algorithm (ssa;gillespie algorithm) and de young-keiser model. a set of different concentration for cat' and ip3 havebeen used. considering the number of molecules in each state, a non linear behavior of the system can beseen clearly. the inhibiting role of the ca+2 on the open state (x110) has been studied. the d...

To date, a number of numerical methods, including the popular Finite-Difference Time Domain (FDTD) technique, have been proposed to simulate Ground-Penetrating Radar (GPR) responses. Despite having a number of advantages, the finite-difference method also has pitfalls such as being very time consuming in simulating the most common case of media with high dielectric permittivity, causing the for...

an electric arc furnace (eaf) is known as nonlinear and time variant load that causes power quality (pq) problems such as, current, voltage and current harmonics, voltage flicker, frequency changes in power system. one of the most important problems to study the eaf behavior is the choice of a suitable model for this load. hence, in this paper, a probabilistic three-phase model is proposed base...

In  this  paper,  a  method  is  presented  for  damage  detection  of  bridges  using  the  Enhanced Colliding Bodies Optimization (ECBO)  utilizing time-domain responses. The finite element modeling of the structure is based on  the equation of motion under the moving load, and the flexural stiffness of the structure is determined by the acceleration responses obtained via sensors placed in d...