3,662 research outputs found

    Unsteady Temperature Distribution for Laminar Flow in a Porous Straight Channel

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    Temperature distribution in a viscous incompressible fluid flowing between two parallel porous flat plates has been investigated when the lower plate is injecting the fluid while the upper one is sucking it with the same rate. Viscous dissipation has been neglected and the rate of heat generation per unit volume per unit time has been taken to be a function of time. Laplace transform technique has been used to obtain an expression for the temperature distribution. Taking the rate of heat generation as an oscillating function of time, numerical work has been done to demonstrate the effects of the variation of the cross-flow velocity on the temperature distribution

    A Note on the Temperature Distribution in a Porous Annulus

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    Unsteady temperature distribution for flow of an incompressible viscous fluid in a porous annulus has been investigated under the assumption that the rate of injection of the fluid at the inner cylinder is equal to the rate of suction of the fluid at the outer one. Viscous dissipation has been neglected while rate of heat generation in the fluid has been accounted for. An expression for the temperature distribution has been obtained using Laplace transform technique and taking the temperatures of the boundaries to be functions of time

    Evaluating the Usability of Automatically Generated Captions for People who are Deaf or Hard of Hearing

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    The accuracy of Automated Speech Recognition (ASR) technology has improved, but it is still imperfect in many settings. Researchers who evaluate ASR performance often focus on improving the Word Error Rate (WER) metric, but WER has been found to have little correlation with human-subject performance on many applications. We propose a new captioning-focused evaluation metric that better predicts the impact of ASR recognition errors on the usability of automatically generated captions for people who are Deaf or Hard of Hearing (DHH). Through a user study with 30 DHH users, we compared our new metric with the traditional WER metric on a caption usability evaluation task. In a side-by-side comparison of pairs of ASR text output (with identical WER), the texts preferred by our new metric were preferred by DHH participants. Further, our metric had significantly higher correlation with DHH participants' subjective scores on the usability of a caption, as compared to the correlation between WER metric and participant subjective scores. This new metric could be used to select ASR systems for captioning applications, and it may be a better metric for ASR researchers to consider when optimizing ASR systems.Comment: 10 pages, 8 figures, published in ACM SIGACCESS Conference on Computers and Accessibility (ASSETS '17

    Heat Transfer for Laminar Flow Through Parallel Porous Disks

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    The problem of temperature distribution and heat transfer for laminar flow through two parallel porous disks, has been investigated when the flow is entirely due t injection or suction at the two disks. Viscous dissipation terms have been included in the energy equation and the uniform injection/suction velocities at the two disks, are assumed to be small. The boundaries are maintained at constant temperature. The variation of temperature and Nusselt numbers at the two disks, is shown graphically, for various of the injection/suction velocities

    Lepton Flavor Violating Z Decays in the Zee Model

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    We calculate lepton flavor violating (LFV) Z decays Z \to {{e_i^\pm}}e_j^\mp (i, j = e, \mu, \tau ; i\neq j) in the Zee model keeping in view the radiative leptonic decays e_i\to e_j\gamma (i = \mu, \tau ; j = e, \mu ; i\neq j), \mu decay and anomalous muon magnetic moment (\mu AMM). We investigate three different cases of Zee f_{ij} coupling (A) f_{e\mu}^2 = f_{\mu\tau}^2= f_{\tau e}^2, (B) f_{e\mu}^2 \gg f_{\tau e}^2 \gg f_{\mu\tau}^2, and (C) f_{\mu\tau}^2 \gg f_{e\mu}^2 \gg f_{\tau e}^2 subject to the neutrino phenomenology. Interestingly, we find that, although the case (C) satisfies the large excess value of \mu AMM, however, it is unable to explain the solar neutrino experimental result, whereas the case (B) satisfies the bi-maximal neutrino mixing scenario, but confronts with the result of \mu AMM experiment. We also find that among all the three cases, only the case (C) gives rise to largest contribution to the ratio B(Z\to e^\pm\tau^\mp)/B(Z\to \mu^\pm \mu^\mp) \simeq {10}^{-8} which is still two order less than the accessible value to be probed by the future linear colliders, whereas for the other two cases, this ratio is too low to be observed even in the near future for all possible LFV Z decay modes.Comment: 12 pages, RevTex, 2 figures, 3 Tables, typos corrected, reference added, version to appear in Phys. Rev.

    Role of excipients and polymeric advancements in preparation of floating drug delivery systems

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    Abstract Since decade or two, the development of floating drug delivery systems becomes a significant and novel tool as having low density than gastric content. There are various advanced polymers including chitosan, eudragit, etc., and excipients such as; pore forming agent, surfactants, etc. All of them are discussed briefly, and results are concluded from various reputed researches. We have discussed all natural and synthetic systems with their effect on the release and other parameters which are essential for the floating formulation development

    Hierarchical Four-Neutrino Oscillations With a Decay Option

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    We present a new and novel synthesis of all existing neutrino data regarding the disappearance and appearance of νe\nu_e and νμ\nu_\mu. We assume four neutrinos: νe,νμ,ντ\nu_e, \nu_\mu, \nu_\tau, as well as a heavier singlet neutrino νs\nu_s of a few eV. The latter may decay into a massless Goldstone boson (the singlet Majoron) and a linear combination of the doublet antineutrinos. We comment on how this scenario may be verified or falsified in future experiments.Comment: 13 pages, no figur

    A Light Sterile Neutrino in the TopFlavor Model

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    A scenario based on the TopFlavor model is presented to explain the origin of a light sterile neutrino as indicated by all combined neutrino oscillation experiments. The model is phenomenologically well motivated and compatible with all available low-energy data. The derived nuetrino mass matrix can qualitatively explain the observed hierarchy in the neutrino mass splittings as indicated by the neutrino oscillation data. Numerical results are obtained for special cases.Comment: Plain Latex file, 12 page

    Constraints On Radiative Neutrino Mass Models From Oscillation Data

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    The three neutrino Zee model and its extension including three active and one sterile species are studied in the light of new neutrino oscillation data. We obtain analytical relations for the mixing angle in solar oscillations in terms of neutrino mass squared differences. For the four neutrino case, we obtain the result sin22θ1[(ΔmAtm2)2/(4ΔmLSND2Δm2)]2\mathsf{sin^2 2 \theta_\odot \approx 1 - [ (\Delta m^2_{Atm})^2/(4 \Delta m^2_{LSND} \Delta m^2_\odot) ]^2}, which can accommodate both the large and small mixing scenarios. We show that within this framework, while both the SMA-MSW and the LMA-MSW solutions can easily be accommodated, it would be difficult to reconcile the LOW-QVO solutions. We also comment on the active-sterile admixture within phenomenologically viable textures.Comment: The paper has been substantially rewritten, especially in Section IV, though the basic results are unchanged. Some new references and an appendix have been adde

    Revising Neutrino Oscillation Parameter Space With Direct Flavor-Changing Interactions

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    We formulate direct, neutrino flavor-changing interactions in a framework that fits smoothly with the parameterization of two-and three-state mixing of massive neutrino states. We show that even small direct interaction strengths could have important consequences for the interpretation of currently running and proposed oscillation experiments. The oscillation amplitude and the borders of the allowed regions in two-and three-flavor mixing parameter space can be sensitieve to the presence of direct interactions when the transition probability is small. We use extensively the high sensitivity of the NOMAD experiment to illustrate potentially large effects from small, direct flavor violation. In the purely leptonic sector, we find that the clean muon neutrino and electron neutrino beams from a muon collider could provide the sharpest tests of direct flavor violation.Comment: 16 pages, 10 figure
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