1,442 research outputs found

    Evaluation of Routing Protocols in Ad Hoc Networks

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    Ad hoc networks are comprised of a group of workstations or other wireless devices which communicate directly with each other to exchange information without centralized control or established infrastructure. In recent years, several routing protocols have been proposed for ad hoc networks and prominent among them are DSR, AODV and TORA. This survey paper provides an overview of these protocols by presenting their characteristics, functionality, benefits and limitations and then makes their comparative analysis. The objective is to make observations about how the performance of these protocols can be improved by using the quality assurance metrics

    The CERN disposal of the FELIX project proposal: Some comments on and justification for it

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    The authors seriously questioned and still continue to question the overemphasised “prospects” in the past of the so-called FELIX project in the domain of ultrahigh-energy astroparticle physics and the optimism that was nourtured around it. This was and is somewhat irrational because there is so far no dearth in the accumulated data for the testing of the models for particle production. But that up to now we failed to build up a really and concretely standard theory of particle production is due to our poverty in outllook and philosophy. The authors picked up and pointed out the very basic down-to-earth observables which even in the available energy range would really suffice to judge the merits and successes of any of the models. That the spirit of FELIX-like proposals might resurrect with just some other name even after the present (and temporary?) setback of the FELIX project remains the point of concern to the authors

    Non-rotating and rotating neutron stars in the extended field theoretical model

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    We study the properties of non-rotating and rotating neutron stars for a new set of equations of state (EOSs) with different high density behaviour obtained using the extended field theoretical model. The high density behaviour for these EOSs are varied by varying the ω\omega-meson self-coupling and hyperon-meson couplings in such a way that the quality of fit to the bulk nuclear observables, nuclear matter incompressibility coefficient and hyperon-nucleon potential depths remain practically unaffected. We find that the largest value for maximum mass for the non-rotating neutron star is 2.1M2.1M_\odot. The radius for the neutron star with canonical mass is 12.814.112.8 - 14.1 km provided only those EOSs are considered for which maximum mass is larger than 1.6M1.6M_\odot as it is the lower bound on the maximum mass measured so far. Our results for the very recently discovered fastest rotating neutron star indicate that this star is supra massive with mass 1.72.7M1.7 - 2.7M_\odot and circumferential equatorial radius 121912 - 19 km.Comment: 28 pages, 12 figures. Phys. Rev. C (in press

    Statistically Comparable UV-spectrophotometric Method development for the Estimation of Probenecid in tablet Dosage Form with the Application of Hydrotropic Solubilization Phenomenon.

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    Statistically comparable method has been developed, validated, for estimating probenecid in tablet dosage form with the application of hydrotropic solubilization phenomenon. This research effort utilizes 2M sodium acetate as hydrotropic solubilizing agent which enhances the aqueous solubility of probenecid by 85 folds. The drug stability in hydrotropic solution was found to be more than 48hrs.The probenecid hydrotrope obeys the Beers Lambert law at maximum wavelength of 244.5nm. The drug response was found to be linear in the range of 2 26 g/ml with correlation coefficient of 0.9987.The non-interference of hydrotropic agent and additives in the course of probenecid estimation ensures the specificity of the proposed method.The mean recovery of 99.43% reflects its accuracy, obtained in good terms. The method precision results were found to be within limit expressed in %RSD (NMT 2%). The results of comparison of proposed method with standard method (IP 2010) were found to be in the similar range. The comparison provides evidence of proposed method to be simple, less time consuming, safe and eco-friendly. The validation (as per ICH 2005) of the proposed method accesses its use in the routinely quality control of probenecid in tablet dosage form

    Correlations in the properties of static and rapidly rotating compact stars

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    Correlations in the properties of the static compact stars (CSs) and the ones rotating with the highest observed frequency of 1122Hz are studied using a large set of equations of state (EOSs). These EOSs span various approaches and their chemical composition vary from the nucleons to hyperons and quarks in β\beta-equilibrium. It is found that the properties of static CS, like, the maximum gravitational mass MmaxstatM_{\rm max}^{\rm stat} and radius R1.4statR_{1.4}^{\rm stat} corresponding to t he canonical mass and supramassive or non-supramassive nature of the CS rotating at 1122 Hz are strongly correlated. In particular, only those EOSs yield the CS rotating at 1122Hz to be non-supramassive for which \left (\frac{M_{\rm max}^{\rm stat}}{M_\odot}\right )^{1/2} \left (\frac{10{\rm km}}{R_{1.4}^{\rm stat}})^{3/2} is greater than unity. Suitable parametric form which can be used to split the MmaxstatM_{\rm max}^{\rm stat} - R1.4statR_{1.4}^{\rm stat} plane into the regions of different supramassive nature of the CS rotating at 1122Hz is presented. Currently measured maximum gravitational mass 1.76MM_\odot of PSR J0437-4715 suggests that the CS rotating at 1122Hz can be non-supramassive provided R1.4stat12.4R_{1.4}^{\rm stat} \leqslant 12.4 km.Comment: 13 pages, 4 figures, Appearing in Phys. Rev.

    The Dielectric Response of La0.5Ca0.5-xSrxMnO3 (0.1 <= x <= 0.4) Manganites with Different Magnetic Ground States

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    The dielectric behavior of half doped manganites La0.5Ca0.5-xSrxMnO3 (0.1 \leq \times \leq 0.4) with varying magnetic ground states has been studied. The real part of relative permittivity as a function of temperature {\epsilon}^'(T), exhibits a maximum around the ferromagnetic (TC) and charge ordering transition (TCO) temperatures accompanied with high dielectric losses. The activation energies obtained for x = 0.1 and 0.3 samples below TCO are the same ~ 0.12eV, whereas the relaxation time constant varies in the range 2.8 \times 10-9 s - 6.03 \times 10-11 s. In contrast to samples having x \leq 0.3, for x = 0.4 doping the dielectric permittivity exhibits a strong temperature dependence in the vicinity of magnetic phase transitions. This behavior may be correlated with the presence of competing magnetic interactions (magnetic polarons) close to the magnetic transitions.Comment: 14 pages, 5 figures, To appear in Journal of Applied Physic

    Oral intake during labor and its effect on labor progression in Indian women at a tertiary care centre

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    Background: Assessment of the subjective perception of the women regarding satisfaction of oral intake during labor and the effect of oral intake on cervical dilatation rates and labor duration in low-risk laboring women. Methods: A prospective observational study was conducted from January 2021-July 2022 in a tertiary care hospital with 176 low risk laboring women. Satisfaction of oral intake in labor was assessed by a questionnaire post-delivery and the answers were analysed among various parous groups and were correlated with cervical dilatation rates in active and latent phase and duration of labor. Results: Based on the satisfaction of oral intake in labor, the patients were divided into very satisfied, satisfied, neutral and dissatisfied group. Only 6.7% of primigravidas and 25% of multigravidas were very satisfied with oral intake. Patients who were dissatisfied and not satisfied with oral intake had slower median rates of cervical dilation of 0.45 cm/hour and 1.25 cm/hour in latent and active phase respectively compared to the very satisfied group who had a rate of 0.5 cm/hour and 2.4 cm/hour in the latent and active phase in primigravidas. The mean duration of the first and second stage of labor was 15.5 hours and 50 minutes in the dissatisfied group which was prolonged compared to the patients who had very satisfied oral intake in labor with a duration of 9.6 hours and 30.8 minutes respectively among the primi-gravidas Conclusions: In primi-gravidas the cervical dilation rates were faster in the group who were very satisfied and satisfied with their oral intake compared to the group who were dissatisfied. The labor duration was also prolonged among the dissatisfied group

    Exploring the extended density-dependent Skyrme effective forces for normal and isospin-rich nuclei to neutron stars

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    We parameterize the recently proposed generalized Skyrme effective force (GSEF) containing extended density dependence. The parameters of the GSEF are determined by the fit to several properties of the normal and isospin-rich nuclei. We also include in our fit a realistic equation of state for the pure neutron matter up to high densities so that the resulting Skyrme parameters can be suitably used to model the neutron star with the "canonical" mass (1.4M\sim 1.4 M_\odot). For the appropriate comparison we generate a parameter set for the standard Skyrme effective force (SSEF) using exactly the same set of the data as employed to determine the parameters of the GSEF. We find that the GSEF yields larger values for the neutron skin thickness which are closer to the recent predictions based on the isospin diffusion data. The Skyrme parameters so obtained are employed to compute the strength function for the isoscalar giant monopole, dipole and quadrupole resonances. It is found that in the case of GSEF, due to the the larger value of the nucleon effective mass the values of centroid energies for the isoscalar giant resonances are in better agreement with the corresponding experimental data in comparison to those obtained using the SSEF. We also present results for some of the key properties associated with the neutron star of "canonical" mass and for the one with the maximum mass.Comment: 45pages, 16 figure
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