Fine structure levels of Cl V and their lifetimes

We report a large scale configuration interaction calculation of Cl V by taking account of relativistic effect through the Breit-Pauli approximation. Excitation energies of the lowest 49 fine structure levels relative to the ground state are found to be in good agreement with the NIST recommended data. Oscillator strengths, line strengths and radiative rates for the optically allowed and intercombination transitions among these levels and life times for some relatively longer lived fine structure levels are also reported for this ion. We confirm the interesting result that the life times for the multiplets of and are of the order of microseconds.Received: 28 May 2003, Published online: 12 August 2003PACS: 32.10.Fn Fine and hyperfine structure - 32.70.Cs Oscillator strengths, lifetimes, transition moments - 95.30.Ky Atomic and molecular data, spectra, and spectral parameters (opacities, rotation constants, line identification, oscillator strengths, gf values, transition probabilities, etc.)     

Stability and persistence of two-dimensional patterns

The canonical equations for evolution of the amplitude order parameters order parameters describing the nonlinear development and persistence of two-dimensional three-mode spatial patterns generated by Turing instability in dissipative systems are considered. The stability conditions for persistent hexagonal patterns are generalized, and the conditions under which patterns are either disrupted, exhibit bounded quasiperiodic or chaotic behavior, or decay under nonlinear evolution are derived. These conditions are applied to the specific three-mode amplitude evolution equations derived for the Schnakenberg model and a delay predator system in Chapter 3. Numerical results are presented for the persistence, disruption and decay of patterns in these systems, including fairly detailed comparisons with simulations results for the Snackenberg model.     

On the variation of cut-off frequency with emitter end concentration of a diffused base transistor

The effect of mobility degradation at high impurity concentrations on the cut-off frequency of a diffused base transistor with exponential impurity profile in the base has been considered analytically. It has been shown that the cut-off frequency exhibits a maximum with increase in emitter and concentration. The results are compared with those of complementary error function and Gaussian base impurity profiles.     

Selective electroless plating-A new technique for GaAs MMICs

A simple, cost-effective processing technique, selective electroless plating, is proposed for GaAs monolithic microwave integrated circuits (MMICs). Microwave measurements show that the attenuation properties of transmission lines fabricated by this processing technique are comparable to the attenuation properties of lines fabricated by the traditional evaporation lift-off technique     

On the Lie Symmetry,Conservation Laws and Painlevé Analysis for the Viscous Transonic Equation

The properties of the nonlinear viscous transonic equation is analysed in detail. The Painlevé test shows that it is not completely integrable. The equation does not reduce to a member of Painlevé class by any similarity transformation of variables.     

Dilatonic Black Holes and Test Particles

A detailed analysis of the motion of the test particles around dilatonic black hole has been done. Here we have studied test particles with various masses, charges and dilatonic charges in equilibrium and non equilibrium situations.     

Priority Access Schemes Using CSMA-CD

Some CSMA-CD schemes for multiple priority message classes are suggested. For all the schemes, an approximate analytic technique for calculating the mean packet delay (for each priority) at the stable operating point of the system has been developed. The analytic results are tested against computer simulation. A Poisson packet arrival process and a general packet length distribution are considered. The mean packet retransmission delay is a general function of priority and the number of unsuccessful attempts. There is a variation in delay differences among priorities for the different schemes. This allows one to single out the particular scheme that is optimal for a given system delay requirement. Some of the priority schemes possess the desirable property of having less average delay compared to a corresponding nonpriority system.     

Copyright protection for electronic publishing over computernetworks

One of the major challenges faced by electronic publishing is that of preventing individuals from easily copying and illegally distributing electronic documents. The authors explore the use of cryptographic protocols to discourage the distribution of illicit electronic copies, and propose an architecture and two separate strategies for making electronic document distribution secure