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OBOME - Ontology based opinion mining in UBIPOL
Ontologies have a special role in the UBIPOL system, they help to structure the policy related context, provide conceptualization for policy domain and use in the opinion mining process. In this work we presented a system called Ontology Based Opinion Mining Engine (OBOME) for analyzing a domain-specific opinion corpus by first assisting the user with the creation of a domain ontology from the corpus. We determined the polarity of opinion on the various domain aspects. In the former step, the policy domain aspect has are identified (namely which policy category is represented by the concept). This identification is supported by the policy modelling ontology, which describe the most important policy – related classes and structure. Then the most informative documents from the corpus are extracted and asked the user to create a set of aspects and related keywords using these documents. In the latter step, we used the corpus specific ontology to model the domain and extracted aspect-polarity associations using grammatical dependencies between words. Later, summarized results are shown to the user to analyze and store. Finally, in an offline process policy modeling ontology is updated
Dynamic interaction between structure and liquid propellants in a space shuttle vehicle model, part 1 Final report
Dynamic interaction between structure and liquid propellants in space shuttle vehicle model
Coupling between structure and liquids in a parallel stage space shuttle design
A study was conducted to determine the influence of liquid propellants on the dynamic loads for space shuttle vehicles. A parallel-stage configuration model was designed and tested to determine the influence of liquid propellants on coupled natural modes. A forty degree-of-freedom analytical model was also developed for predicting these modes. Currently available analytical models were used to represent the liquid contributions, even though coupled longitudinal and lateral motions are present in such a complex structure. Agreement between the results was found in the lower few modes
Analytical and numerical studies of central galactic outflows powered by tidal disruption events -- a model for the Fermi bubbles?
Capture and tidal disruption of stars by the supermassive black hole in the
Galactic center (GC) should occur regularly. The energy released and dissipated
by this processes will affect both the ambient environment of the GC and the
Galactic halo. A single star of super-Eddington eruption generates a subsonic
out ow with an energy release of more than erg, which still is not
high enough to push shock heated gas into the halo. Only routine tidal
disruption of stars near the GC can provide enough cumulative energy to form
and maintain large scale structures like the Fermi Bubbles. The average rate of
disruption events is expected to be ~ yr, providing
the average power of energy release from the GC into the halo of dW/dt ~
3*10 erg/s, which is needed to support the Fermi Bubbles. The GC black
hole is surrounded by molecular clouds in the disk, but their overall mass and
filling factor is too low to stall the shocks from tidal disruption events
significantly. The de facto continuous energy injection on timescales of Myr
will lead to the propagation of strong shocks in a density stratified Galactic
halo and thus create elongated bubble-like features, which are symmetric to the
Galactic midplane.Comment: 11 pages, 5 figures. The title and abstract have been changed.
Accepted by Astrophysical Journa
The Construction of a Partially Regular Solution to the Landau-Lifshitz-Gilbert Equation in
We establish a framework to construct a global solution in the space of
finite energy to a general form of the Landau-Lifshitz-Gilbert equation in
. Our characterization yields a partially regular solution,
smooth away from a 2-dimensional locally finite Hausdorff measure set. This
construction relies on approximation by discretization, using the special
geometry to express an equivalent system whose highest order terms are linear
and the translation of the machinery of linear estimates on the fundamental
solution from the continuous setting into the discrete setting. This method is
quite general and accommodates more general geometries involving targets that
are compact smooth hypersurfaces.Comment: 43 pages, 2 figure
Two-point motional Stark effect diagnostic for Madison Symmetric Torus
A high-precision spectral motional Stark effect (MSE) diagnostic provides internal magnetic field measurements for Madison Symmetric Torus (MST) plasmas. Currently, MST uses two spatial views-on the magnetic axis and on the midminor (off-axis) radius, the latter added recently. A new analysis scheme has been developed to infer both the pitch angle and the magnitude of the magnetic field from MSE spectra. Systematic errors are reduced by using atomic data from atomic data and analysis structure in the fit. Reconstructed current density and safety factor profiles are more strongly and globally constrained with the addition of the off-axis radius measurement than with the on-axis one only
Discrete Morse functions for graph configuration spaces
We present an alternative application of discrete Morse theory for
two-particle graph configuration spaces. In contrast to previous constructions,
which are based on discrete Morse vector fields, our approach is through Morse
functions, which have a nice physical interpretation as two-body potentials
constructed from one-body potentials. We also give a brief introduction to
discrete Morse theory. Our motivation comes from the problem of quantum
statistics for particles on networks, for which generalized versions of anyon
statistics can appear.Comment: 26 page
Particle acceleration and the origin of gamma-ray emission from Fermi Bubbles
Fermi LAT has discovered two extended gamma-ray bubbles above and below the
galactic plane. We propose that their origin is due to the energy release in
the Galactic center (GC) as a result of quasi-periodic star accretion onto the
central black hole. Shocks generated by these processes propagate into the
Galactic halo and accelerate particles there. We show that electrons
accelerated up to ~10 TeV may be responsible for the observed gamma-ray
emission of the bubbles as a result of inverse Compton (IC) scattering on the
relic photons. We also suggest that the Bubble could generate the flux of CR
protons at energies > 10^15 eV because the shocks in the Bubble have much
larger length scales and longer lifetimes in comparison with those in SNRs.
This may explain the the CR spectrum above the knee.Comment: 5 pages, 4 figures. Expanded version of the contribution to the 32nd
ICRC, Beijing, #0589. To appear in the proceeding
Relative effects on global warming of halogenated methanes and ethanes of social and industrial interest
The relative potential global warming effects for several halocarbons (chlorofluorocarbons (CFC's)-11, 12, 113, 114, and 115; hydrochlorofluorocarbons (HCFC's) 22, 123, 124, 141b, and 142b; and hydrofluorocarbons (HFC's) 125, 134a, 143a, and 152a; carbon tetrachloride; and methyl chloroform) were calculated by two atmospheric modeling groups. These calculations were based on atmospheric chemistry and radiative convective models to determine the chemical profiles and the radiative processes. The resulting relative greenhouse warming when normalized to the effect of CFC-11 agree reasonably well as long as we account for differences between modeled lifetimes. Differences among results are discussed. Sensitivity of relative warming values is determined with respect to trace gas levels assumed. Transient relative global warming effects are analyzed
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