Collineations of the curvature tensor in general relativity

Curvature collineations for the curvature tensor, constructed from a fundamental Bianchi Type-V metric, are studied. We are concerned with a symmetry property of space-time which is called curvature collineation, and we briefly discuss the physical and kinematical properties of the models.     

Green function theory of anisotropic Heisenberg Ferromagnet with biquadratic exchange

The effects of biquadratic exchange interaction and the uniaxial anisotropy on the curie temperature of the Heisenberg Ferromagnet with spin-one has been studied. Green function technique with random phase approximation has been used. The variation of curie temperature with biquadratic and anisotropic parameters for different lattices has been discussed.     

A unique method for reducing losses of bends in dielectric optical wave guide

The dielectric optical wave guide is finding growing attention at millimeter wave frequencies. However the dielectric optical waveguide radiates at bends and thus transmission loss increases. These radiations are in the outword direction of bends. This output radiation at output bends arises due to change in phase velocities of the propagating wave at the centre of the dielectric guide and the phase velocity at the outer surface of the dielectric guide. A unique methiod is suggested to avoid these radiation losses.Experimental results are also shown at microwave frequencies.     

Common Fixed Points of Commuting Mappings in 2-Metric Spaces and an Application

We prove some interior regularity properties of the displacements and stresses for a quasistatic elasto-visco-plastic modell in continuum mechanics.     

Electrical deviations from Matthiessen's rule in A Ag:Au alloy

Electrical resistivity of Ag:0.29 at % Au alloy has been measured and explained theoretically with the aim of understanding the deviations from Matthiessen's rule. The anisotropy in the electron-phonon interaction, the recoil of the impurity, mass-changes, nearest neighbour radial and angular force-constant-changes and Debye-Waller factors have been taken into consideration.