7,292 research outputs found
EMEEDP: Enhanced Multi-hop Energy Efficient Distributed Protocol for Heterogeneous Wireless Sensor Network
In WSN (Wireless Sensor Network) every sensor node sensed the data and
transmit it to the CH (Cluster head) or BS (Base Station). Sensors are randomly
deployed in unreachable areas, where battery replacement or battery charge is
not possible. For this reason, Energy conservation is the important design goal
while developing a routing and distributed protocol to increase the lifetime of
WSN. In this paper, an enhanced energy efficient distributed protocol for
heterogeneous WSN have been reported. EMEEDP is proposed for heterogeneous WSN
to increase the lifetime of the network. An efficient algorithm is proposed in
the form of flowchart and based on various clustering equation proved that the
proposed work accomplishes longer lifetime with improved QOS parameters
parallel to MEEP. A WSN implemented and tested using Raspberry Pi devices as a
base station, temperature sensors as a node and xively.com as a cloud. Users
use data for decision purpose or business purposes from xively.com using
internet.Comment: 6 pages, 4 figures. arXiv admin note: substantial text overlap with
arXiv:1409.1412 by other author
Shape-changing Collisions of Coupled Bright Solitons in Birefringent Optical Fibers
Wecritically review the recent progress in understanding soliton propagation
in birefringent optical fibers.By constructing the most general bright
two-soliton solution of the integrable coupled nonlinear Schroedinger equation
(Manakov model) we point out that solitons in birefringent fibers can in
general change their shape after interaction due to a change in the intensity
distribution among the modes even though the total energy is conserved.
However, the standard shape-preserving collision (elastic collision) property
of the (1+1)-dimensional solitons is recovered when restrictions are imposed on
some of the soliton parameters. As a consequence the following further
properties can be deduced using this shape-changing collision. (i) The exciting
possibility of switching of solitons between orthogonally polarized modes of
the birefringent fiber exists. (ii) When additional effects due to periodic
rotation of birefringence axes are considered, the shape changing collision can
be used as a switch to suppress or to enhance the periodic intensity exchange
between the orthogonally polarized modes. (iii) For ultra short optical soliton
pulse propagation in non-Kerr media, from the governing equation an integrable
system of coupled nonlinear Schroedinger equation with cubic-quintic terms is
identified. It admits a nonlocal Poisson bracket structure. (iv) If we take the
higher-order terms in the coupled nonlinear Schroedinger equation into account
then their effect on the shape-changing collision of solitons, during optical
pulse propagation, can be studied by using a direct perturbational approach.Comment: 14 pages, ROMP31, 4 EPS figure
A Ray-Tracing Model of the Vela Pulsar
In the relativistic plasma surrounding a pulsar, a subluminal ordinary-mode
electromagnetic wave will propagate along a magnetic field line. After some
distance, it can break free of the field line and escape the magnetosphere to
reach an observer. We describe a simple model of pulsar radio emission based on
this scenario and find that applying this model to the case of the Vela pulsar
reproduces qualitative characteristics of the observed Vela pulse profile.Comment: 23 pages, 9 figures, accepted for publication in Ap
Impact of Tandem Repeats on the Scaling of Nucleotide Sequences
Techniques such as detrended fluctuation analysis (DFA) and its extensions
have been widely used to determine the nature of scaling in nucleotide
sequences. In this brief communication we show that tandem repeats which are
ubiquitous in nucleotide sequences can prevent reliable estimation of possible
long-range correlations. Therefore, it is important to investigate the presence
of tandem repeats prior to scaling exponent estimation.Comment: 14 Pages, 3 Figure
The observational evidence pertinent to possible kick mechanisms in neutron stars
We examine available observations on pulsars for evidence pertaining to
mechanisms proposed to explain the origin of their velocities. We find that
mechanisms predicting a correlation between the rotation axis and the pulsar
velocity are ruled out. Also, that there is no significant correlation between
pulsar magnetic field strengths and velocities. With respect to recent
suggestions postulating asymmetric impulses at birth being solely responsible
for both the spins and velocities of pulsars, single impulses of any duration
and multiple extended duration impulses appear ruled out.Comment: 7 pages. Accepted for publication in Astronomy & Astrophysic
Nutritive value of the crab Podophthalmus vigil (Fabricius)
Among the edible crabs, Podophthalmus vigil occupies a distinct position in Porto Novo coast. Though the fishery is seasonal, P. vigil supports an additional crab fishery from august to october. An attempt has been made to evaluate the nutritional status of different size groups of P. vigil. It has been observed that protein and moisture values are more in smaller crabs, corresponding with a drop in carbohydrate and fat. In bigger size groups, the values of fat and carbohydrate are found to be higher, while protein and moisture contents decreased slightly. The total meat content varies in different crabs of the same size group and the average value of the total consumable part is found to be only less than 30% of the total weight of the animal
Fishery and ecology of the spiny lobster Panulirus homarus (Linnaeus, 1758) at Khadiyapatanam in the southwest coast of India
Commercial exploitation of palinurid lobsters has been on the
increase due to high demand and lucrative price for live lobsters
in the international market. The spiny lobster Panulirus homarus
caught generally by traps and bottom-set gillnets support
significant commercial catches along the southern Indian coast.
Fishery along the southwest coast is seasonal, extending from
September to March and peak landings are during October to
December. The catch gradually declines from January and the
landing is negligible in April and May. The paper presents
results of a field study carried out on the ecology of the lobster
fishing ground at Khadiyapatanam, on the southwest coast of
India. Hydrographical parameters were used to correlate the
lobster catch from the coastal fishing grounds during the fishing
(October-November) and the non-fishing season (April-May) for
which lobster catch and the entangled associated fauna and
flora from 8 bottom-set-gillnets operated at different depth
zones were monitored. Mean catch in the bottom-set- gillnet
varied from 1.6 to 0.68 kg/net/day during October-January and
0.1 kg/net/day during April-May. Negative correlation between
bottom sea water temperature and the catch of P. homarus was
observed. The environmental and ecological conditions, widespread
beds of the brown mussel Perna indica are likely to be
impacting the abundance of P. homarus at Khadiyapatanam
fishing ground. The major groups of organisms in the fishing
ground were echinoderms, fishes, sponges, crustaceans and
molluscs. The paper discusses the probable influence of
environmental and ecological factors that impact the distribution
and fishery of P. homarus in the fishing grounds of
Khadiyapatanam
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