Now showing items 161-168 of 168
Least-squares finite element approximations to solutions of interface problems
(Siam Publications, 1998-02)
A least-squares finite element method for second-order elliptic boundary value problems having interfaces due to discontinuous media properties is proposed and analyzed. Both Dirichlet and Neumann boundary data are treated. ...
Interferometric Model For Phase Analysis in Fiber Couplers
(Optical Society of America, 1996-07-01)
An interferometric model is proposed to estimate the phase differences in lossless, strongly coupled biconical fiber couplers. This approximate method is simpler than the traditional s-parameter network theory-based analysis ...
iterative image-processing using a cavity with a phase-conjugate mirror
(Optical Society of America, 1992-05)
We describe an optical image processing system with regenerative feedback that utilizes a cavity with a phase-conjugate mirror. The system's characteristics and limitations are discussed, and its application to the ...
positive pulse switching in coupled nonlinear Fabry-Perot cavities
(Optical Society of America, 1991-05)
It is shown that positive pulse switching is possible in a system of two coupled nonlinear Fabry-Perot cavities. The conditions in which a signal beam can be switched on and off by positive pulses in the steady state regime ...
Raman studies of sol-gel alumina - finite-size effects in nanocrystalline ALO(OH)
(American Physical Society, 1993-12-01)
A systematic Raman-scattering investigation has been carried out on sol-gel alumina prepared by the hot-water hydrolysis and condensation of AI(OC4H9)3, the Yoldas process, as a function of process variables such as the ...
Dependence of fluorescence lifetimes of Y2O3 : Eu3+ nanoparticles on the surrounding medium
(American Physical Society, 1999-11)
The radiative lifetime, tau(R), of the D-5(0) metastable excited state of Eu3+ ions in nanocrystalline monoclinic Y2O3 samples is about four times longer than that in the micron size powder of the same material. The Eu3+ ...