A Novel Self-Organizing Approach to Automatic Traffic Light Management System for Road Traffic Network

Wireless Personal Communications - Traffic network is basically a “network of networks” consisting of mainly two types of networks: road network and a travel network. Due to drastic...     

Energy policy implications of waste management in various sectors of the economy—An analysis based on physical systems theory

This paper aims to bring into focus the impact of waste management in different sectors of the economy on some important policy issues related to energy. In a multi-sector economy, the total energy demand consists of the direct energy demand of human population, the intermediate demand of other sectors and the energy wastes which cannot be recycled and have to be rejected to nature. These sectorial interlinkages in the economy, due to their cascading effects, are very important for studying the real impact of waste generation or waste recycling on the energy demand and prices. A generalized multi-sector economy model which combines the concepts of input-output economics with waste management (input-output-waste model) has been developed based on physical systems theory. The results of sensitivity analysis of this model are presented in this paper, which suggest the need to have a serious look into waste management practices in all sectors of the economy from an energy policy point of view.     

Effect of velocity slip in axially undefined porous bearings

A theoretical analysis of the performance characteristics of axially undefined journal bearings was carried out. The analysis takes into account the velocity slip at the surface of the porous medium by using the Beavers-Joseph criterion. Results are presented for various bearing characteristics and compared with earlier results obtained by using the no-slip condition.     

CaS: Bi as U.V. dosimeter

Stable CaS: Bi phosphors have been prepared under optimum reducing conditions. These phosphors exhibit two thermoluminescence peaks at 60° and 200°C, except at very low or high concentrations of the dopant. The use of the high temperature (dosimetric) peak in CaS: Bi (0.05%) has suggested for monitoring ultraviolet doses without any pre-irradiation. The effects of annealing, fading, dose response and monochromatic excitation have also been studied.     

Squeeze films in porous bearings

Squeeze film behaviour in a narrow porous journal bearing is analysed. The analytical model takes into account the effect of porosity by assuming that the flow in the porous matrix obeys Darcy's law. The modified Reynolds' equation is derived to account for the porosity of the bearing. The expressions for pressure distribution and load capacity are given in closed form while the time-height relation is obtained by numerical integration. The results are shown graphically for selected parameter values. It is found that the time taken in reducing a given height is significantly less as compared to the corresponding time for a non-porous bearing. For highly porous bearings the squeezing effects are not significant.     

Synthesis and characterization of bismuth doped barium sulphide nanoparticles

We have synthesized BaS:Bi nanocrystalline powder of average grain size 35 nm by solid-state diffusion method using sodium thiosulphate as a flux. During this work we have optimized the nature and amount of flux, amount of the dopant and temperature of firing for maximum yield of photoluminescence. The samples were characterized by X-ray powder diffraction (XRD) method, transmission electron microscopy (TEM), photoluminescence (PL) and UV-visible techniques. On excitation by 425 nm, these nanophosphors give one emission peak at 575 nm which corresponds to green color. In the excitation spectra of these particles there are two peaks at 350 nm and 425 nm. The effect of dopant concentration on the photoluminescence of BaS:Bi nanocrystallites has been studied which is in agreement with the principle of concentration quenching. The energy band gap of bismuth doped BaS nanopowder has been calculated to be 4.25 eV and is blue shifted in comparison to their bulk counterparts. The blue shift may be due to the quantum confinement in the particles.