8,412 research outputs found
Length-weight, length-length relationship of the spiny eel, Macrognathus pancalus (Hamilton 1822) sampled from Ganges and Brahmaputra river basins, India
The freshwater spiny eel, Macrognathus pancalus is an inland water teleost fish commonly known as barred or striped spiny eel found in Asia. The sampling areas were selected which are spatially and geographically different and characterized by different environmental conditions in order to elucidation of ecotype. A total 345 specimens were collected from the sampling sites during January 2008 to December 2010. The weight of M. pancalus in the present study nearly the cube of its length in all cases as the values of regression coefficient âbâ were found to be close to 3. The length weight relationship indicated the isometric growth in all the samples of striped spiny eel collected from different environmental condition. The coefficient of regression âbâ were more in the riverine population (3.17±0.08) as compared to the populations of a large lake i.e. Beel (2.85±0.13). The coefficient of determination, (r2) in all the cases was highly significant (p< 0.001). The relative condition factor (Kn) were also calculated and the average of condition factor in riverine and beel populations of spiny eel were found to be 0.50±0.09, and 0.47±0.05, respectively. The length-length relationship was highly correlated (r2= 0.99 at P<0.0001) for all the individuals of both habitats. A significant size difference was also noted between the river basin populations of M.pancalus. In the present study the length-weight, length-length relationship of M.pancalus in two different river basins was compared
Positioning and Surveying Requirements for Exploration and Exploitation of Ocean Wealth
Deep sea mining, such as is now being planned to be carried out in the Indian Ocean, requires an accurate positioning system for navigation and for the control of the equipment. Short range systems using electromagnetic principles cover only a limited area while the longer range systems which can be used for offshore, deep ocean work although covering large areas, have limited accuracy. This paper reviews the requirements for position fixing systems for deep ocean mining and the ways to reach the best solution at the most reasonable cost
Fair Access to Scarce Medical Capacity for Non-Covid-19 Patients: A Role for Reserves
As hospitals in the US and elsewhere fill again with patients with covid-19, discussions about how to fairly allocate scarce medical resources have come to the fore once again. One frequently voiced concern is that non-covid-19 patients with urgent health needs are facing indefinitely postponed surgeries, long-distance hospital transfers, or even are unable to access medical treatment. In our view, a reserve or categorised priority system could help. It could be used to fairly distribute scarce medical capacityâsuch as staffing, physical space, and medical treatmentsâbetween covid-19 and non-covid-19 patients, just as it has been used or proposed to allocate covid-19 therapeutics and vaccines
Performance of ZrB2âCu composite as an EDM electrode
The low wear resistance of electrodes like Cu, Cu alloys and graphite is a major problem for electrical discharge machining (EDM) operation. Here an attempt has been made to develop a metal matrix composite (ZrB2âCu) to get an optimum combination of wear resistance, electrical and thermal conductivity. The ZrB2âCu composite have been developed by adding different amounts of Cu and tested as a tool material at different process parameters of EDM during machining of mild steel. The ZrB2â40 wt.% Cu composite shows more metal removal rate (MRR) with less tool removal rate (TRR) than commonly used Cu tool. But the diameteral overcut and average surface roughness are found to be lesser in case of Cu tool than composite tool. The tools and workpiece surfaces are analyzed by scanning electron microscope (SEM)/EDS and XRD technique
Hysteresis Loop Effect on Coronal Index and Solar Flare Index During Solar Cycles 22 and 23
The hysteresis loop effect on the solar activity as coronal index (CI) and solar flare index (SFI) over cosmic ray intensity (CRI) at the low cut-off rigidities neutron monitoring station Oulu on the monthly basis data for the period January 1, 1986 to December 31, 2008 has been studied. It is observed that the shape of the hysteresis loops is varying from solar cycle 22 to 23. The hysteresis loops for solar cycle 23 are broad ovals whereas for solar cycle 22 are nearly flat. A complementary feature of the cosmic ray intensity decreases more rapidly as the increase in solar activity (coronal index and solar flare index). The positive solar polar magnetic parameter (A>0) and negative solar polar magnetic parameter (A<0) is representing the hysteresis loops
Exploration of the Continental Margins of India
In mid 1970âs the Institute prepared a plan for systematic regional geological and geophysical surveys of the continental margins of India. This involved over 75,000 km of underway (bathymetric, side scan sonar, magnetic, gravity and seismic) surveys on tracks about 20 km apart, and collection of about 1500 seabed samples at about 10 to 20 km spacing. It was anticipated that the entire programme would require 22 shipâs months. This programme received considerable impetus from sponsored surveys of other organizations, chiefly the oil industry, ports and harbours as well as industries disposing of their effluents in the marine environment. By now the entire western continental shelf and a large part of the continental slope have been covered by about 68,314 km bathymetric surveys, 12,720 km side scan sonar surveys, 46,222 km magnetic surveys, 27,200 km seismic surveys (including 5,489 km multichannel seismic), and 9,065 km gravity surveys. Approximately 1500 seabed samples have been collected. These surveys, besides providing basic information on the morphology, sediments, and geochemistry of the sediments of the .western continental margin of India, have also led to the estimation of resources of offshore ilmenite placers and low grade phosphorite deposits. The data collected are proposed to be depicted in a series of maps showing the morphology, sediments and geochemistry of sediments
Bounded Model Checking for Probabilistic Programs
In this paper we investigate the applicability of standard model checking
approaches to verifying properties in probabilistic programming. As the
operational model for a standard probabilistic program is a potentially
infinite parametric Markov decision process, no direct adaption of existing
techniques is possible. Therefore, we propose an on-the-fly approach where the
operational model is successively created and verified via a step-wise
execution of the program. This approach enables to take key features of many
probabilistic programs into account: nondeterminism and conditioning. We
discuss the restrictions and demonstrate the scalability on several benchmarks
Efficacy of some weed control methods in soybean during kharif season
An experiment was undertaken at the C block research farm of Bidhan Chandra Krishi Viswavidyalaya, Kalyani, Nadia, West Bengal, to find out the efficacy of some weed control methods in soybean (cv. Bragg) during kharif season of 2011 -12 and 2012-13. The experiment was conducted in randomized block design (RBD) with 8 treatments in 4 replications. Treatments comprised of two different kinds of mulching (paddy straw @ 5 t ha-1 and polyethylene), two herbicides (Flumioxazin @ 30 g a.i. ha-1 as pre-emergence and Quizalofop-ethyl @ 50 g a.i. ha-1 as post-emergence) alone and in combination, twice hand weeding at 25 and 50 days after sowing (DAS), integrated approach of Flumioxazin @ 30 g a.i. ha-1 as pre-emergence along with one hand weeding at 25 DAS and one weedy check treatment. Among the weed control treatments, twice hand weeding at 25 and 50 DAS resulted the highest control of weeds (5.91 gm-2, 6.09 gm-2 at 30 DAS and at harvest respectively) and produced the highest grain yield at harvest (2797 kg ha-1), followed by Flumioxazin @ 30 g a.i. ha-1 as pre-emergence along with one hand weeding at 25 DAS, straw mulch @ 5 t ha-1, polyethylene mulch and combination of Flumioxazin @ 30 g a.i. ha-1 as pre-emergence + Quizalofop-ethyl @ 50 g a.i. ha-1 as post-emergence
Role of the van Hove Singularity in the Quantum Criticality of the Hubbard Model
A quantum critical point (QCP), separating the non-Fermi liquid region from
the Fermi liquid, exists in the phase diagram of the 2D Hubbard model
[Vidhyadhiraja et. al, Phys. Rev. Lett. 102, 206407 (2009)]. Due to the
vanishing of the critical temperature associated with a phase separation
transition, the QCP is characterized by a vanishing quasiparticle weight. Near
the QCP, the pairing is enhanced since the real part of the bare d-wave p-p
susceptibility exhibits algebraic divergence with decreasing temperature,
replacing the logarithmic divergence found in a Fermi liquid [Yang et. al,
Phys. Rev. Lett. 106, 047004 (2011)]. In this paper we explore the
single-particle and transport properties near the QCP. We focus mainly on a van
Hove singularity (vHS) coming from the relatively flat dispersion that crosses
the Fermi level near the quantum critical filling. The flat part of the
dispersion orthogonal to the antinodal direction remains pinned near the Fermi
level for a range of doping that increases when we include a negative
next-near-neighbor hopping t' in the model. For comparison, we calculate the
bare d-wave pairing susceptibility for non-interacting models with the usual
two-dimensional tight binding dispersion and a hypothetical quartic dispersion.
We find that neither model yields a vHS that completely describes the critical
algebraic behavior of the bare d-wave pairing susceptibility. The resistivity,
thermal conductivity, thermopower, and the Wiedemann-Franz Law are examined in
the Fermi liquid, marginal Fermi liquid, and pseudo-gap doping regions. A
negative next-near-neighbor hopping t' increases the doping region with
marginal Fermi liquid character. Both T and negative t' are relevant variables
for the QCP, and both the transport and the motion of the vHS with filling
suggest that they are qualitatively similar in their effect.Comment: 15 pages, 17 figure
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