99,394 research outputs found
Raman spectroscopic determination of the length, strength, compressibility, Debye temperature, elasticity, and force constant of the C-C bond in graphene
From the perspective of bond relaxation and vibration, we have reconciled the
Raman shifts of graphene under the stimuli of the number-of-layer,
uni-axial-strain, pressure, and temperature in terms of the response of the
length and strength of the representative bond of the entire specimen to the
applied stimuli. Theoretical unification of the measurements clarifies that:
(i) the opposite trends of Raman shifts due to number-of-layer reduction
indicate that the G-peak shift is dominated by the vibration of a pair of atoms
while the D- and the 2D-peak shifts involves z-neighbor of a specific atom;
(ii) the tensile strain-induced phonon softening and phonon-band splitting
arise from the asymmetric response of the C3v bond geometry to the C2v
uni-axial bond elongation; (iii) the thermal-softening of the phonons
originates from bond expansion and weakening; and (iv) the pressure- stiffening
of the phonons results from bond compression and work hardening. Reproduction
of the measurements has led to quantitative information about the referential
frequencies from which the Raman frequencies shift, the length, energy, force
constant, Debye temperature, compressibility, elastic modulus of the C-C bond
in graphene, which is of instrumental importance to the understanding of the
unusual behavior of graphene
ASAP : towards accurate, stable and accelerative penetrating-rank estimation on large graphs
Pervasive web applications increasingly require a measure of similarity among objects. Penetrating-Rank (P-Rank) has been one of the promising link-based similarity metrics as it provides a comprehensive way of jointly encoding both incoming and outgoing links into computation for emerging applications. In this paper, we investigate P-Rank efficiency problem that encompasses its accuracy, stability and computational time. (1) We provide an accuracy estimate for iteratively computing P-Rank. A symmetric problem is to find the iteration number K needed for achieving a given accuracy ε. (2) We also analyze the stability of P-Rank, by showing that small choices of the damping factors would make P-Rank more stable and well-conditioned. (3) For undirected graphs, we also explicitly characterize the P-Rank solution in terms of matrices. This results in a novel non-iterative algorithm, termed ASAP , for efficiently computing P-Rank, which improves the CPU time from O(n 4) to O( n 3 ). Using real and synthetic data, we empirically verify the effectiveness and efficiency of our approaches
Differential Entropy on Statistical Spaces
We show that the previously introduced concept of distance on statistical
spaces leads to a straightforward definition of differential entropy on these
statistical spaces. These spaces are characterized by the fact that their
points can only be localized within a certain volume and exhibit thus a feature
of fuzziness. This implies that Riemann integrability of relevant integrals is
no longer secured. Some discussion on the specialization of this formalism to
quantum states concludes the paper.Comment: 4 pages, to appear in the proceedings of the joint meeting of the 2nd
International Conference on Cybernetics and Information Technologies, Systems
and Applications (CITSA 2005) and the 11th International Conference on
Information Systems Analysis and Synthesis (ISAS 2005), to be held in
Orlando, USA, on July 14-17, 200
Semi-inclusive deeply inelastic (anti)neutrino nucleus scattering
The (anti)neutrino nucleus scattering plays a very important role in probing
the hadronic structure as well as the electroweak phenomenologies. To this end,
we calculate the jet production semi-inclusive deeply inelastic (anti)neutrino
nucleus scattering process. The initial (anti)neutrino is assumed to be
scattered off by a target particle with spin 1. Due to the limitation of the
factorization theorem, calculations are carried out in the quantum
chromodynamics parton model framework up to tree level twist-3. We consider
both the neutral current and the charged current processes and write them into
a unified form due to the similar interaction forms. Considering the angular
modulations and polarizations of the cross section, we calculate the complete
azimuthal asymmetries. We also calculate the intrinsic asymmetries which reveal
the imbalance in the distribution of the intrinsic transverse momentum of the
quark. We find that these asymmetries can be expressed in terms of the
transverse momentum-dependent parton distribution functions (TMD PDFs) and the
electroweak couplings. With the determined couplings, these asymmetries can be
used to extract the TMD PDFs and further to study the hadronic structures.Comment: 8 figure
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