119 research outputs found
Scope of Energy Consumption & Energy Conservation in Indian auto part manufacturing Industry
Energy is crucial to human sustenance and development. Due to the increase in the Demand of energy and deficiency in power generation, day by day the gap between demand and supply of electric energy is widening. Bridging this gap from the supply side is very difficult and expensive proposition. Also limited energy resources, scarcity of capital and high interest costs for the addition of new generation capacity is leading to the increased cost of electrical energy in India. Â The only viable way to handle this crisis, apart from capacity addition, is the efficient use of available energy, which is possible only by continuously monitoring and controlling the use of electrical energy. Hence energy management program is a systematic and scientific process to identify the potential for improvements in energy efficiency, to recommend the ways with or without financial investment, to achieve estimated saving energy and energy cost. It is estimated that Industrial energy use in developing countries constitutes about 45-50 % of the total commercial energy consumption. Much of this energy is converted from imported oil, the price of which has increased tremendously so much so that most of developing countries spent more than 50 % of their foreign exchange earnings. Not with standing these fiscal constraints, developing countries need to expand its industrial base like us if it has to generate the resources to improve the quality of life of its people. The expansion of industrial base does require additional energy inputs which become more & more difficult in the present scenario. In this competitive world, cost competitiveness is very essential for survival of every individual have to save the energy so is equal to the generate energy. To establish any work / motive or task, energy in one or other form is an essential component. Thus the need to conserve energy, particularly in industry and commerce is strongly felt as the energy cost takes up substantial share in the overall cost structure of the operation. Hence it calls MANAGEMENT OF ENERGY or in other words MANAGEMENT OF RESOURCES or ENERGY CONSERVATION
Quantum Tunneling, Blackbody Spectrum and Non-Logarithmic Entropy Correction for Lovelock Black Holes
We show, using the tunneling method, that Lovelock black holes Hawking
radiate with a perfect blackbody spectrum. This is a new result. Within the
semiclassical (WKB) approximation the temperature of the spectrum is given by
the semiclassical Hawking temperature. Beyond the semiclassical approximation
the thermal nature of the spectrum does not change but the temperature
undergoes some higher order corrections. This is true for both black hole
(event) and cosmological horizons. Using the first law of thermodynamics the
black hole entropy is calculated. Specifically the -dimensional static,
chargeless black hole solutions which are spherically symmetric and
asymptotically flat, AdS or dS are considered. The interesting property of
these black holes is that their semiclassical entropy does not obey the
Bekenstein-Hawking area law. It is found that the leading correction to the
semiclassical entropy for these black holes is not logarithmic and next to
leading correction is also not inverse of horizon area. This is in contrast to
the black holes in Einstein gravity. The modified result is due to the presence
of Gauss-Bonnet term in the Lovelock Lagrangian. For the limit where the
coupling constant of the Gauss-Bonnet term vanishes one recovers the known
correctional terms as expected in Einstein gravity. Finally we relate the
coefficient of the leading (non-logarithmic) correction with the trace anomaly
of the stress tensor.Comment: minor modifications, two new references added, LaTeX, JHEP style, 34
pages, no figures, to appear in JHE
On the Thermodynamic Geometry of BTZ Black Holes
We investigate the Ruppeiner geometry of the thermodynamic state space of a
general class of BTZ black holes. It is shown that the thermodynamic geometry
is flat for both the rotating BTZ and the BTZ Chern Simons black holes in the
canonical ensemble. We further investigate the inclusion of thermal
fluctuations to the canonical entropy of the BTZ Chern Simons black holes and
show that the leading logartithmic correction due to Carlip is reproduced. We
establish that the inclusion of thermal fluctuations induces a non zero scalar
curvature to the thermodynamic geometry.Comment: 1+17 pages, LaTeX, 4 eps figure
Glassy Phase Transition and Stability in Black Holes
Black hole thermodynamics, confined to the semi-classical regime, cannot
address the thermodynamic stability of a black hole in flat space. Here we show
that inclusion of correction beyond the semi-classical approximation makes a
black hole thermodynamically stable. This stability is reached through a phase
transition. By using Ehrenfest's scheme we further prove that this is a glassy
phase transition with a Prigogine-Defay ratio close to 3. This value is well
placed within the desired bound (2 to 5) for a glassy phase transition. Thus
our analysis indicates a very close connection between the phase transition
phenomena of a black hole and glass forming systems. Finally, we discuss the
robustness of our results by considering different normalisations for the
correction term.Comment: v3, minor changes over v2, references added, LaTeX-2e, 18 pages, 3 ps
figures, to appear in Eour. Phys. Jour.
Exact Differential and Corrected Area Law for Stationary Black Holes in Tunneling Method
We give a new and conceptually simple approach to obtain the first law of
black hole thermodynamics from a basic thermodynamical property that entropy
(S) for any stationary black hole is a state function implying that dS must be
an exact differential. Using this property we obtain some conditions which are
analogous to Maxwell's relations in ordinary thermodynamics. From these
conditions we are able to explicitly calculate the semiclassical
Bekenstein-Hawking entropy, considering the most general metric represented by
the Kerr-Newman spacetime. We extend our method to find the corrected entropy
of stationary black holes in (3+1) dimensions. For that we first calculate the
corrected Hawking temperature considering both scalar particle and fermion
tunneling beyond the semiclassical approximation. Using this corrected Hawking
temperature we compute the corrected entropy, based on properties of exact
differentials. The connection of the coefficient of the leading (logarithmic)
correction with the trace anomaly of the stress tensor is established . We
explicitly calculate this coefficient for stationary black holes with various
metrics, emphasising the role of Komar integrals.Comment: references added, typos corrected, LaTeX, 28 pages, no figures, to
appear in JHE
Cosmological distance indicators
We review three distance measurement techniques beyond the local universe:
(1) gravitational lens time delays, (2) baryon acoustic oscillation (BAO), and
(3) HI intensity mapping. We describe the principles and theory behind each
method, the ingredients needed for measuring such distances, the current
observational results, and future prospects. Time delays from strongly lensed
quasars currently provide constraints on with < 4% uncertainty, and with
1% within reach from ongoing surveys and efforts. Recent exciting discoveries
of strongly lensed supernovae hold great promise for time-delay cosmography.
BAO features have been detected in redshift surveys up to z <~ 0.8 with
galaxies and z ~ 2 with Ly- forest, providing precise distance
measurements and with < 2% uncertainty in flat CDM. Future BAO
surveys will probe the distance scale with percent-level precision. HI
intensity mapping has great potential to map BAO distances at z ~ 0.8 and
beyond with precisions of a few percent. The next years ahead will be exciting
as various cosmological probes reach 1% uncertainty in determining , to
assess the current tension in measurements that could indicate new
physics.Comment: Review article accepted for publication in Space Science Reviews
(Springer), 45 pages, 10 figures. Chapter of a special collection resulting
from the May 2016 ISSI-BJ workshop on Astronomical Distance Determination in
the Space Ag
Collapsing bubble in metal for high energy density physics study
This paper presents a new idea to produce matter in the high energy density physics (HEDP) regime in the laboratory using an intense ion beam. A gas bubble created inside a solid metal may collapse by driving it with an intense ion beam. The melted metal will compress the gas bubble and supply extra energy to it. Simulations show that the spherical implosion ratio can be about 5 and at the stagnation point, the maximum density, temperature and pressure inside the gas bubble can go up to nearly 2 times solid density, 10 eV and a few megabar (Mbar) respectively. The proposed experiment is the first to permit access into the Mbar regime with existing or near-term ion facilities, and opens up possibilities for new physics gained through careful comparisons of simulations with measurements of quantities like stagnation radius, peak temperature and peak pressure at the metal wall
Antiproliferative and genotoxic effects of nature identical and artificial synthetic food additives of aroma and flavor
Toxicity of synthetic flavorings, nature identical and artificial, to hematopoietic tissue cells of rodents
Search for Gravitational Waves Associated with Gamma-Ray Bursts Detected by Fermi and Swift during the LIGO-Virgo Run O3b
We search for gravitational-wave signals associated with gamma-ray bursts (GRBs) detected by the Fermi and Swift satellites during the second half of the third observing run of Advanced LIGO and Advanced Virgo (2019 November 1 15:00 UTC-2020 March 27 17:00 UTC). We conduct two independent searches: A generic gravitational-wave transients search to analyze 86 GRBs and an analysis to target binary mergers with at least one neutron star as short GRB progenitors for 17 events. We find no significant evidence for gravitational-wave signals associated with any of these GRBs. A weighted binomial test of the combined results finds no evidence for subthreshold gravitational-wave signals associated with this GRB ensemble either. We use several source types and signal morphologies during the searches, resulting in lower bounds on the estimated distance to each GRB. Finally, we constrain the population of low-luminosity short GRBs using results from the first to the third observing runs of Advanced LIGO and Advanced Virgo. The resulting population is in accordance with the local binary neutron star merger rate. © 2022. The Author(s). Published by the American Astronomical Society
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