760 research outputs found
Properties of large scale plasma flow during the early stage of the plasmaspheric refilling
The objective is to better characterize the macroscopic properties of the interhemisphere plasma flow by solving a more complete set of hydrodynamic equations than that solved previously. Specifically, the ion continuity, momentum and energy equations were solved for the plasma flow along the closed magnetic field lines. During the initial stage of the supersonic outflow in the equatorial region, the ions cool substantially. Using the hydrodynamic model for the large-scale plasma flow, the dynamics of shocks was examined which form in the geomagnetic flux tubes during the early stages of refilling. These shocks are more like those forming in neutral gases than the electrostatic shocks driven by microinstabilities involving ion-ion interaction. Therefore, the shocks seen in the hydrodynamic model are termed as hydrodynamic shocks. Such shocks are generally unsteady and therefore the usual shock jump conditions given by Rankine-Hugoniot relations are not strictly applicable to them. The density, flow velocity and temperature structures associated with the shocks are examined for both asymmetrical and symmetrical flows. In the asymmetrical flow the outflow from one of two conjugate ionospheres is dominant. On the other hand, in the symmetrical case outflows from the two ionospheric sources are identical. Both cases are treated by a two-stream model. In the late type of flow, the early-time refilling shows a relaxation type of oscillation, which is driven by the large-scale interactions between the two identical streams. After this early stage, the resulting temperature structure shows some interesting features. In the equatorial region the streams are isothermal, but in the off-equatorial regions the streams have quite different temperatures, and also densities and flow velocities. The dense and slow stream is found to be warmer than the low-density fast stream. In the late stage of refilling, the temperature is found to steadily increase from the conjugate ionospheres towards the equator; the equatorial temperature is found to be as high as about 8000 K compared to the ionospheric temperature of 3600 K
Build an app and they will come? Lessons learnt from trialling the GetThereBus app in rural communities
Acknowledgements The research described here was supported by the award made by the RCUK Digital Economy programme to the dot.rural Digital Economy Hub; award reference: EP/G066051/1.Peer reviewedPostprin
Center to limb observations and modeling of the Ca I 4227 A line
The observed center-to-limb variation (CLV) of the scattering polarization in
different lines of the Second Solar Spectrum can be used to constrain the
height variation of various atmospheric parameters, in particular the magnetic
fields via the Hanle effect. Here we attempt to model non-magnetic CLV
observations of the profiles of the Ca I 4227 A line recorded with the
ZIMPOL-3 at IRSOL. For modeling, we use the polarized radiative transfer with
partial frequency redistribution with a number of realistic 1-D model
atmospheres. We find that all the standard FAL model atmospheres, used by us,
fail to simultaneously fit the observed (, ) at all the limb distances
(). However, an attempt is made to find a single model which can provide a
fit at least to the CLV of the observed instead of a simultaneous fit to
the (, ) at all . To this end we construct a new 1-D model by
combining two of the standard models after modifying their temperature
structures in the appropriate height ranges. This new combined model closely
reproduces the observed at all the , but fails to reproduce the
observed rest intensity at different . Hence we find that no single 1-D
model atmosphere succeeds in providing a good representation of the real Sun.
This failure of 1-D models does not however cause an impediment to the magnetic
field diagnostic potential of the Ca I 4227 A line. To demonstrate this we
deduce the field strength at various positions without invoking the use
of radiative transfer.Comment: 20 pages, 10 figures, Accepted for publication in Ap
Electro-Osmotic Flow of MHD Jeffrey Fluid in a Rotating Microchannel by Peristalsis: Thermal Analysis
In this study, we examine the rotating and heat transfer on the peristaltic and electro-osmatic flow of a Jeffery fluid in an asymmetric microchannel with slip impact. A pressure gradient and anal axially imposed electric field work together to impact the electro-osmotic flow (EOF). Mathematical modeling is imported by employing the low Reynolds number and long wavelength approximation. The exact solution has been simplified for the stream function, temperature, and velocity distributions. The effects of diverse egress quantities on the gush virtue are exhibited and discussed with the help of graphs. The shear stress and trapping phenomena have been investigated. The characterization of results has been resolved for the flow governing ingrained appropriate parameters by employing the table. Our findings can be summarized as follows: (i) Debye length has a strong influence on the conducting viscous fluid of EOF in non-uniform micro-channel. (ii) The temperature field is enhanced through the elevated values of the rotation parameter and EOF. (iii) The shear stress has oscillatory behavior and the heat transmission rate increases with the magnitude of larger values of EOF. Finally, there is good agreement between the current results and those that have already been published. This model applies to the study of chemical fraternization/separation procedures and bio-microfluidic devices for the resolution of diagnosis
Training in Aura Reading: Results from a Small Quasi-Experimental Study in India (Research Note)
The aura is believed to be an invisible field surrounding the physical body, interpenetrating and extending beyond it. The present study examines whether appearance of an aura-like phenomenon around the hand can be perceived visually after a short training session. A quasi-experimental research design was employed with 47 participants with a mean age of 19 years. Results from before and after attempting to view an aura-like phenomenon around the hand were analyzed using Contingency Coefficient analysis. The results suggest that an aura-like phenomenon can be detected around the hand since the participants narrated several experiences that were novel (
Kejriwal - Redefining Indian politics
With its promise to weed out corruption from public life, Arvind Kejriwal’s Aam Aadmi Party (AAP, Common Man Party) captured the imagination of millions of Indians. So much so that his one-year-old party was catapulted to power after the December 2013 elections in the state of Delhi (India). With a well worked out strategy which included a promise to introduce a bill which made everyone in the government including the prime minister accountable, Kejriwal’s AAP party projected itself as an alternative to the existing political parties which were known for deep-rooted corruption. Working closely with the grass-roots,
formulating manifestos for each and every constituency, taking the opinion of the people on
every major decision, taking the use of social media to a totally new level, AAP gained
tremendous popularity among the voters. Having formed the government, it now remains to be seen how it will achieve its promises, which according to its critics, were impossible to
fulfill
Development of an integrated flexible transport systems platform for rural areas using argumentation theory
Peer reviewedPublisher PD
Can a Lamb Reach a Haven Before Being Eaten by Diffusing Lions?
We study the survival of a single diffusing lamb on the positive half line in
the presence of N diffusing lions that all start at the same position L to the
right of the lamb and a haven at x=0. If the lamb reaches this haven before
meeting any lion, the lamb survives. We investigate the survival probability of
the lamb, S_N(x,L), as a function of N and the respective initial positions of
the lamb and the lions, x and L. We determine S_N(x,L) analytically for the
special cases of N=1 and N--->oo. For large but finite N, we determine the
unusual asymptotic form whose leading behavior is S_N(z)\simN^{-z^2}, with
z=x/L. Simulations of the capture process very slowly converge to this
asymptotic prediction as N reaches 10^{500}.Comment: 13 pages, 6 figures, IOP format; v2: small changes in response to
referee and editor comment
TRIBAL PLANTS AND THEIR INBORN ANTIMICROBIAL ACTIVITIES
The importance of medicinal plants in traditional health-care practices provides clues to new areas of research and in the biodiversity of conservation. Right from the beginning, the documentation of traditional knowledge, especially on the medicinal uses of plants, has provided many important drugs for the modern day. Even today, this area holds much more hidden treasure as almost 80% of the human population in developing countries depend on plant resources for health care. Keeping this in view, the present study was initiated to document the traditionally used tribal plants and their inborn antimicrobial activity which is enhanced on the synthesis of noble metal nanoparticles
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