736 research outputs found
Criticality of tuning in athermal phase transitions
We experimentally address the importance of tuning in athermal phase
transitions, which are triggered only by a slowly varying external field acting
as tuning parameter. Using higher order statistics of fluctuations, a singular
critical instability is detected for the first time in spite of an apparent
universal self-similar kinetics over a broad range of driving force. The
results as well as the experimental technique are likely to be of significance
to many slowly driven non-equilibrium systems from geophysics to material
science which display avalanche dynamics.Comment: 5 pages, 4 figure
Volume Integral Theorem for Exotic Matter
We answer an important question in general relativity about the volume
integral theorem for exotic matter by suggesting an exact integral quantifier
for matter violating Averaged Null Energy Condition (ANEC). It is checked
against some well known static, spherically symmetric traversable wormhole
solutions of general relativity with a sign reversed kinetic term minimally
coupled scalar field. The improved quantifier is consistent with the principle
that traversable wormholes can be supported by arbitrarily small quantities of
exotic matter.Comment: 7 page
Development of cost-effective phasor measurement unit for wide area monitoring system applications
Sustained growth in the demand with unprecedented investments in the transmission infrastructure resulted in narrow operational margins for power system operators across the globe. As a result, power networks are operating near to stability limits. This has demanded the electrical utilities to explore new avenues for control and protection of wide area systems. Present supervisory control and data acquisition/energy management systems (SCADA/EMS) can only facilitate steady state model of the network, whereas synchrophasor measurements with GPS time stamp from wide area can provide dynamic view of power grid that enables supervision, and protection of power network and allow the operator to take necessary control/remedial measures in the new regime of grid operations. Construction of phasor measurement unit (PMU) that provide synchrophasors for the assessment of system state is widely accepted as an essential component for the successful execution of wide area monitoring system (WAMS) applications. Commercial PMUs comes with many constraints such as cost, proprietary hardware designs and software. All these constraints have limited the deployment of PMUs at high voltage transmission systems alone. This paper addresses the issues by developing a cost-effective PMU with open-source hardware, which can be easily modified as per the requirements of the applications. The proposed device is tested with IEEE standards
Signature of Martensite transformation on conductivity noise in thin films of NiTi shape memory alloys
Slow time-dependent fluctuations, or noise, in the electrical resistance of
dc magnetron sputtered thin films of Nickel Titanium shape memory alloys have
been measured. Even in equilibrium, the noise was several orders of magnitude
larger than that of simple diffusive metallic films, and was found to be
non-monotonic around the martensitic transformation regime. The results are
discussed in terms of dynamics of structural defects, which also lay foundation
to a new noise-based characterization scheme of martensite transformation.Comment: 4 pages, 3 figure
Nutritional status and socioeconomic empowerment of fisherwomen in the coastal ecosystem of Andhra Pradesh, Karnataka, Kerala and Tamil Nadu, India
This study was carried out in the coastal areas of Andhra Pradesh, Karnataka,
Kerala and Tamil Nadu. From these states, 13 districts and 28 villages were
selected. A total of 5,744 households were covered. Cereal consumption was
highest in Andhra Pradesh followed by Kerala, Karnataka and Tamil Nadu. Pulse
consumption was high in Kerala when compared to other states. The overall
energy intake of the fisherwomen was 1,827 kcal/day; protein intake was 50.6
gm/day; carbohydrate intake was 343.5 gm/day; and fat intake was 27 gm/day.
The mean intake of micronutrients was less than the recommended dietary
allowance. The mean body mass index was 21.3. The nutritional status of the
women was: 49% normal; 17% low normal; 10.5% mildly malnourished; 4%
moderately malnourished; and 2.9% severely malnourished. About 11.5% of
the fisherwomen were overweight and 4.6% were obese. A subsample of 915
women was clinically observed: 34.8% were diagnosed with angular stomatitis;
31 % with cheelosis; 42.8% with bleeding gums; and 44.2% with dry skin. Some
72% of the women were anemic.
An assessment ofthe socioeconomic status indicated that very few households
(15.4%) maintained livestock for income generation. About 60% of the
fisherwomen carried out post-harvest activities to earn income. Food
expenditure comprised 60.7% of the earned income contribvting to the major
share of the spending. Debt servicing was a serious problem faced by 44.9% of
the respondents who had procured loans mostly from non-institutional
sources
Semiclassical and Quantum Field Theoretic Bounds for Traversable Lorentzian Stringy Wormholes
A lower bound on the size of a Lorentzian wormhole can be obtained by
semiclassically introducing the Planck cut-off on the magnitude of tidal forces
(Horowitz-Ross constraint). Also, an upper bound is provided by the quantum
field theoretic constraint in the form of the Ford-Roman Quantum Inequality for
massless minimally coupled scalar fields. To date, however, exact static
solutions belonging to this scalar field theory have not been worked out to
verify these bounds. To fill this gap, we examine the wormhole features of two
examples from the Einstein frame description of the vacuum low energy string
theory in four dimensions which is the same as the minimally coupled scalar
field theory. Analyses in this paper support the conclusion of Ford and Roman
that wormholes in this theory can have sizes that are indeed only a few order
of magnitudes larger than the Planck scale. It is shown that the two types of
bounds are also compatible. In the process, we point out a "wormhole" analog of
naked black holes.Comment: 15 page
Socio-economic status of fisherwomen
In India, women constitute about 50 per cent of the population and comprise one third of the labour force. Women account for 32.5 per cent of the total work force of 121.63 million (1993-94) and the figure is still increasing day by day. Among the different sectors of the Indian economy where women contribute significantly, fishery sector is an important one. Out of the 5.4 million active fishers in India,
3.8 million (70.37%) are fishermen and 1.6 million (29.63%) are fisherwomen
Anthropometric measurements of fisherwomen and preschool children
Anthropometry is one of the methods used in nutritional assessment. Nutritional anthropometry can be defined as measurement of variation of the physical dimensions and the gross composition of the human body at different age levels and degrees of malnutritio
Role of women in Fisheries: An Overview
Women playa key role in the development of fisheries sector in addition to their role of sole household managers in most fisher families
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