16,049 research outputs found
Masses of Scalar and Axial-Vector B Mesons Revisited
The SU(3) quark model encounters a great challenge in describing even-parity
mesons. Specifically, the quark model has difficulties in
understanding the light scalar mesons below 1 GeV, scalar and axial-vector
charmed mesons and charmonium-like state . A common wisdom for
the resolution of these difficulties lies on the coupled channel effects which
will distort the quark model calculations. In this work, we focus on the near
mass degeneracy of scalar charmed mesons, and , and its
implications. Within the framework of heavy meson chiral perturbation theory,
we show that near degeneracy can be qualitatively understood as a consequence
of self-energy effects due to strong coupled channels. Quantitatively, the
closeness of and masses can be implemented by adjusting
two relevant strong couplings and the renormalization scale appearing in the
loop diagram. Then this in turn implies the mass similarity of and
mesons. The interaction with the Goldstone boson is
crucial for understanding the phenomenon of near degeneracy. Based on heavy
quark symmetry in conjunction with corrections from QCD and effects, we
obtain the masses of and mesons, for example,
,
with being
corrections. We find that the predicted mass difference of 48 MeV
between and is larger than that of MeV
inferred from the relativistic quark models, whereas the difference of 15 MeV
between the central values of and is much smaller than
the quark model expectation of MeV.Comment: 21 pages, 1 figure, to appear in Eur. Phys. J. (2017). arXiv admin
note: text overlap with arXiv:1404.377
Video Highlight Prediction Using Audience Chat Reactions
Sports channel video portals offer an exciting domain for research on
multimodal, multilingual analysis. We present methods addressing the problem of
automatic video highlight prediction based on joint visual features and textual
analysis of the real-world audience discourse with complex slang, in both
English and traditional Chinese. We present a novel dataset based on League of
Legends championships recorded from North American and Taiwanese Twitch.tv
channels (will be released for further research), and demonstrate strong
results on these using multimodal, character-level CNN-RNN model architectures.Comment: EMNLP 201
Investigation of the properties of nanostructured Li-doped NiO films using the modified spray pyrolysis method
The lithium-doped nickel oxide (L-NiO) films were synthetized using the modified spray pyrolysis method with a two-step grown process. By observing the spectra of X-ray photoemission spectroscopy of L-NiO films, the intensity of Ni 2p(3/2) peak of Ni(3+) bonding state increases with increasing Li concentration that causes the decrease of transparency and resistivity. The L-NiO films with optimum characteristics were obtained at Li = 8 at%, where a p-type resistivity of 4.1 × 10(−1) Ω cm and optical transparency above 76% in the visible region are achieved
Developing the dielectric mechanisms of polyetherimide/multiwalled carbon nanotube/(Ba0.8Sr0.2)(Ti0.9Zr0.1)O3 composites
Various amounts of multiwalled carbon nanotubes [MWNTs] were embedded into polyetherimide [PEI] to form PEI/MWNT composites, and their dielectric properties were measured at 1 MHz. The Lichtenecker mixing rule was used to find a reasonable dielectric constant for the MWNTs used in this study. The dielectric constants of the developed composites were significantly increased, and the loss tangents were significantly decreased as 2.0 wt.% (Ba0.8Sr0.2)(Ti0.9Zr0.1)O3 ceramic powder [BSTZ] was added to the PEI/MWNTs to form PEI/MWNT/BSTZ composites. The Lichtenecker and Yamada mixing rules were used to predict the dielectric constants of the PEI/MWNT and PEI/MWNT/BSTZ composites. Equivalent electrical conduction models of both composites were established using the two mixing rules. In addition, the theoretical bases of the two mixing rules were used to explain the measured results for the PEI/MWNT and PEI/BSTZ/MWNT composites
Which Type Of Work-Study Experience Is More Beneficial?: Perceptions Of Taiwanese College Students
The rapidly increase of tuition and the reduced financial support from government and families have forced many more students to take part-time jobs, however, different jobs might bear different benefits. The main purpose of this study were to identify the major benefits of part-time jobs or work-study experiences performed by college students, and to calculate the relative weight of each benefits perceived by students, and finally, to determine the most appropriate type of job for college students. A self-developed questionnaire is administered to 250 students from three universities. The results of this study not only help students to select the most appropriate types of job for a given purpose, but also provide school administrators with a guide to develop their student part-time job policies
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