Shape-changing Collisions of Coupled Bright Solitons in Birefringent Optical Fibers

Wecritically review the recent progress in understanding soliton propagation in birefringent optical fibers.By constructing the most general bright two-soliton solution of the integrable coupled nonlinear Schroedinger equation (Manakov model) we point out that solitons in birefringent fibers can in general change their shape after interaction due to a change in the intensity distribution among the modes even though the total energy is conserved. However, the standard shape-preserving collision (elastic collision) property of the (1+1)-dimensional solitons is recovered when restrictions are imposed on some of the soliton parameters. As a consequence the following further properties can be deduced using this shape-changing collision. (i) The exciting possibility of switching of solitons between orthogonally polarized modes of the birefringent fiber exists. (ii) When additional effects due to periodic rotation of birefringence axes are considered, the shape changing collision can be used as a switch to suppress or to enhance the periodic intensity exchange between the orthogonally polarized modes. (iii) For ultra short optical soliton pulse propagation in non-Kerr media, from the governing equation an integrable system of coupled nonlinear Schroedinger equation with cubic-quintic terms is identified. It admits a nonlocal Poisson bracket structure. (iv) If we take the higher-order terms in the coupled nonlinear Schroedinger equation into account then their effect on the shape-changing collision of solitons, during optical pulse propagation, can be studied by using a direct perturbational approach.Comment: 14 pages, ROMP31, 4 EPS figure

EMEEDP: Enhanced Multi-hop Energy Efficient Distributed Protocol for Heterogeneous Wireless Sensor Network

In WSN (Wireless Sensor Network) every sensor node sensed the data and transmit it to the CH (Cluster head) or BS (Base Station). Sensors are randomly deployed in unreachable areas, where battery replacement or battery charge is not possible. For this reason, Energy conservation is the important design goal while developing a routing and distributed protocol to increase the lifetime of WSN. In this paper, an enhanced energy efficient distributed protocol for heterogeneous WSN have been reported. EMEEDP is proposed for heterogeneous WSN to increase the lifetime of the network. An efficient algorithm is proposed in the form of flowchart and based on various clustering equation proved that the proposed work accomplishes longer lifetime with improved QOS parameters parallel to MEEP. A WSN implemented and tested using Raspberry Pi devices as a base station, temperature sensors as a node and xively.com as a cloud. Users use data for decision purpose or business purposes from xively.com using internet.Comment: 6 pages, 4 figures. arXiv admin note: substantial text overlap with arXiv:1409.1412 by other author

The observational evidence pertinent to possible kick mechanisms in neutron stars

We examine available observations on pulsars for evidence pertaining to mechanisms proposed to explain the origin of their velocities. We find that mechanisms predicting a correlation between the rotation axis and the pulsar velocity are ruled out. Also, that there is no significant correlation between pulsar magnetic field strengths and velocities. With respect to recent suggestions postulating asymmetric impulses at birth being solely responsible for both the spins and velocities of pulsars, single impulses of any duration and multiple extended duration impulses appear ruled out.Comment: 7 pages. Accepted for publication in Astronomy & Astrophysic

A Ray-Tracing Model of the Vela Pulsar

In the relativistic plasma surrounding a pulsar, a subluminal ordinary-mode electromagnetic wave will propagate along a magnetic field line. After some distance, it can break free of the field line and escape the magnetosphere to reach an observer. We describe a simple model of pulsar radio emission based on this scenario and find that applying this model to the case of the Vela pulsar reproduces qualitative characteristics of the observed Vela pulse profile.Comment: 23 pages, 9 figures, accepted for publication in Ap

Dynamic Impact of RuCl3 Catalyst on the Oxidation of Cyclamate with Acidified Bromamine-T: Elucidation of Mechanistic Pathways and Kinetic Modeling

Abstract: Oxidation-Kinetics of cyclamate by bromamine-T (BAT) in HClO4 medium catalyzed by RuCl3 exhibits a first-order dependence on BAT0, fractional-order on both Cyclamate0 and RuCl3, and inverse fractional-order on HClO4. RuCl3 catalyst accelerated the reaction by a splendid 48 times. Plausible mechanism and related rate law have been deduced. Graphical Abstract: The Stoichiometry of the reaction is:Figure not available: see fulltext.. © 2017, Springer Science+Business Media New York