7,997 research outputs found
Mechanism of Paper Chromatography of Inorganic Ions on Impregnated Papers: Separation of Ag(I), Cu(II), Ni(II), Co(II), Hg(II), Pb(II) & Fe(III)
1089-109
Synchrotron aging and the radio spectrum of SN 1993J
We combine the GMRT low frequency radio observations of SN 1993J with the VLA
high frequency radio data to get a near simultaneous spectrum around day 3200
since explosion. The low frequency measurements of the supernova determine the
turnover frequency and flux scale of the composite spectrum and help reveal a
steepening in the spectral index, , in the optically
thin part of the spectrum. This is the first observational evidence of a break
in the radio spectrum of a young supernova. We associate this break with the
phenomenon of synchrotron aging of radiating electrons. From the break in the
spectrum we calculate the magnetic field in the shocked region independent of
the equipartition assumption between energy density of relativistic particles
and magnetic energy density. We determine the ratio of these two energy
densities and find that this ratio is in the range: . We also predict the nature of the evolution of the synchrotron break
frequency with time, with competing effects due to diffusive Fermi acceleration
and adiabatic expansion of the radiative electron plasma.Comment: 12 pages, 2 figures. Accepted for publication in ApJ
Design and Implementation of Fuzzy Logic Based Image Fusion Technique
The quality of image holds importance for both humans and machines. To fulfill the requirement of good quality images, image enhancement is needed. Application of a single contrast enhancement technique often does not produce desirable result and may lead to over enhanced images. To overcome this problem image fusion is performed so that better results with desired enhancement can be achieved. In the present paper an amalgamation of image enhancement, fusion and sharpening have been carried out in the candidate algorithm. The algorithm makes use of fuzzy logic for weight calculation. The results are compared with DACE/LIF approach and it is observed that the proposed algorithm improves the result in terms of quality parameters like PSNR (Peak Signal to Noise Ratio), AMBE (Absolute Mean Brightness Error) and SSIM (Structural Similarity Index) by 0.5 dB, 3 and 0.1 respectively from the existing technique
Nickel Resources in India and their Exploitation
NICKEL is one of the important strategic alloying
elements : its consumption has increased considerably
after World War II and during the last few years it increased by 6U-70°,,. It is felt that the increase would have been still higher if more nickel was available. The present annual production outside the communist block has well exceeded 400 000 tons and there is every likelihood of further rise in production in the near future as new production centres are being established. The largest single producer of nickel is Canada with the world's richest deposits at Sudbury, Ontario
Method of measurements with random perturbation: Application in photoemission experiments
We report an application of a simultaneous perturbation stochastic
approximation (SPSA) algorithm to filtering systematic noise (SN) with non-zero
mean value in photoemission data. In our analysis we have used a series of 50
single-scan photoemission spectra of W(110) surface where randomly chosen SN
was added. It was found that the SPSA-evaluated spectrum is in good agreement
with the spectrum measured without SN. On the basis of our results a wide
application of SPSA for evaluation of experimental data is anticipated.Comment: 11 pages, 3 figure
Sustainability through training
This paper summarises the work done over the last six years to improve the supply of water in rural areas of India through specially designed training for engineers
and scientists working in the rural water sector. The programme came into being as a result of the vision of senior staff of the Drinking Water Mission in the
Department of Rural Development of the Ministry of Agriculture in 1990. Since then the support of Mission staff has continued as the responsibility for the activities of the Mission passed first to the Ministry of Rural Development
and recently to the Ministry of Rural Areas and Employment. Financial support was provided for the external input
costs to this programme by the Overseas Development Administration of the United Kingdom Government and internal costs were borne by the Mission
Transforming a Monolithic Sheet of Nitinol into a Passive Reconfigurable Tactile Pixel Array Display at Braille Resolution
The Scope for Development of Magnesium Industry in India
IN THIS era of "sputniks" and "space flights", weight saving poses to be a problem of prince importance with
its direct influence over increasing speed and fuel economy. Magnesium and magnesium base alloys are known
to be the lightest structural materials today, and have been employed not only for space research and rocketry
but for various types of aero, marine and road trans-portation vehicles
Tropospheric Scatter Propagation Measurements Beyond the Horizon in Arid Zone-A Note
Tropospheric scatter study beyond the horizon radio link presently necessitates tests to establish the median path loss and to determine the magnitude and duration of the path loss variations. The average basic transmission loss of the scattered component, Lbs can be found if K (ratio of r.m.s. value of scattered and constant component) and the resultant basic transmission loss Lbm are known. This paper also deals with the diurnal and seasonal behaviour of signal strength, based on the ana!ysis of about ten months recording on a C band Troposcatter Link between Pilani and Delhi
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