5,045 research outputs found
Evolution of massive fields around a black hole in Horava gravity
We study the evolution of massive scalar field in the spacetime geometry of
Kehagias-Sfetsos(KS) black hole in deformed Horava-Lifshitz(HL) gravity by
numerical analysis. We find that the signature of HL theory is encoded in the
quasinormal mode(QNM) phase of the evolution of field. The QNM phase in the
evolution process lasts for a longer time in HL theory. QNMs involved in the
evolution of massive field are calculated and find that they have a higher
oscillation frequency and a lower damping rate than the Schwarzschild spacetime
case. We also study the relaxation of field in the intermediate and asymptotic
range and verified that behaviors of field in these phases are independent of
the HL parameter and is identical to the Schwarzschild case.Comment: The article was fully rewritten, references added, accepted to GR
Collection and estimation of zooplankton
Zooplankters are the diverse, delicate and often very beautiful
assemblages of animals that drift in the waters of the world
oceans. The name zooplankton is derived from the Greek:
Zoon, animal; planktos, wandering. They play a key role
in the marine food web by transferring the organic energy
produced by the unicellular algae to higher trophic levels such
as pelagic stocks. Because of their critical role as food source
for larval and juvenile fish, the dynamics of zooplankton
populations, their reproductive cycles, growth and survival
rates are all important factors influencing recruitment of
fish stocks and thereby the magnitude of fishery. Majority
of them are microscopic, unicellular or multicellular forms
with size ranging from a few microns to a millimeter or
more. In addition to size variations, there are differences
in morphological features and taxonomic position. The
zooplankton plays an important role to study the faunal biodiversity
of aquatic ecosystems
Thermodynamic Geometry of Reissener-Nordstr\"{o}m-de Sitter black hole and its extremal case
We study the thermodynamics and the different thermodynamic geometric methods
of Reissener-Nordstr\"{o}m-de Sitter black hole and its extremal case, which is
similar to the de Sitter black hole coupled to a scalar field, rather called an
MTZ black hole. While studying the thermodynamics of the systems, we could find
some abnormalities. In both cases, the thermodynamic geometric methods could
give the correct explanation for the all abnormal thermodynamic behaviors in
the system.Comment: 11 pages, 8 figures and accepted for publication in Gen. Relativ.
Gravi
Phytoplankton - collection, estimation, classification and diversity
In the existing sampling methodology, the interest is to
estimate gear-wise, species-wise landings for the state in a
month, fishing effort according to different types of fishing
boats and also in terms of man hours. The analysis is carried
out at CMFRI headquarters. Before the data is processed for
analysis it will be ensured that the data collection is made
as per the approved schedule, by checking the appropriate
proforma. The responsibilities and functions of staff at the
headquarters are data coding, estimation and database
management. The data analysis is computerised and
estimates are made using the software developed by the
Fishery Resources Assessment Division of the Institute. The
processed data are again counter- checked for errors. When
discrepancies are detected, the estimation procedure is
scrutinised in detail
Pelagic sharks by-catch in the tuna longline fishery of the Indian EEZ
Several species of pelagic and oceanic sharks are caught by the tuna longliners of
FSI while surveying the oceanic tuna resources in the Indian EEZ. Though the
sharks are not targeted species in tuna longlining, they constitute a major share of
the catches. The sharks hooked could be, therefore, treated as by- catches or incidental
catches of the tuna longline fisher
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