12,501 research outputs found
Fractal and multifractal properties of a family of fractal networks
In this work, we study the fractal and multifractal properties of a family of
fractal networks introduced by Gallos {\it et al.} ({\it Proc. Natl. Acad. Sci.
U.S.A.}, 2007, {\bf 104}: 7746). In this fractal network model, there is a
parameter which is between and , and allows for tuning the level of
fractality in the network. Here we examine the multifractal behavior of these
networks, dependence relationship of fractal dimension and the multifractal
parameters on the parameter . First, we find that the empirical fractal
dimensions of these networks obtained by our program coincide with the
theoretical formula given by Song {\it et al.} ( {\it Nat. Phys}, 2006, {\bf
2}: 275). Then from the shape of the and curves, we find the
existence of multifractality in these networks. Last, we find that there exists
a linear relationship between the average information dimension and
the parameter .Comment: 12 pages, 7 figures, accepted by J. Stat. Mec
Multifractal analysis of weighted networks by a modified sandbox algorithm
Complex networks have attracted growing attention in many fields. As a
generalization of fractal analysis, multifractal analysis (MFA) is a useful way
to systematically describe the spatial heterogeneity of both theoretical and
experimental fractal patterns. Some algorithms for MFA of unweighted complex
networks have been proposed in the past a few years, including the sandbox (SB)
algorithm recently employed by our group. In this paper, a modified SB
algorithm (we call it SBw algorithm) is proposed for MFA of weighted
networks.First, we use the SBw algorithm to study the multifractal property of
two families of weighted fractal networks (WFNs): "Sierpinski" WFNs and "Cantor
dust" WFNs. We also discuss how the fractal dimension and generalized fractal
dimensions change with the edge-weights of the WFN. From the comparison between
the theoretical and numerical fractal dimensions of these networks, we can find
that the proposed SBw algorithm is efficient and feasible for MFA of weighted
networks. Then, we apply the SBw algorithm to study multifractal properties of
some real weighted networks ---collaboration networks. It is found that the
multifractality exists in these weighted networks, and is affected by their
edge-weights.Comment: 15 pages, 6 figures. Accepted for publication by Scientific Report
Dicyanido[tris(2-pyridylmethyl)amine]cobalt(III) hexafluoridophosphate
In the title complex, [Co(CN)2(C18H18N4)]PF6, the CoIII atom together with one of the pyridyl rings and two cyanide anions are located on a mirror plane, while the P atom is located on an inversion centre. The CoIII atom exhibits an octahedral geometry, coordinated by four N atoms from the tris(2-pyridylmethyl)amine ligand with an average Co—N distance of 1.953 (2) Å, and two cyanide C atoms with an average Co—C distance of 1.895 (2) Å. The crystal packing is stabilized by intermolecular C—H⋯N and C—H⋯F interactions
Probing and Interaction at LHC
Many new physics models predict the existence of TeV-scale charged gauge
boson together with Higgs boson(s). We study the
interaction and explore the angular distribution of charged lepton to
distinguish from in process at the LHC. It is found that a new type forward-backward
asymmetry() relating to the angle between the direction of the charged
lepton in rest frame and that of the reconstructed in laboratory
frame is useful to investigate the properties of interaction. We
analyze the Standard Model backgrounds and develop a set of cuts to highlight
the signal and suppress the backgrounds at LHC. We find that can reach
0.03(-0.07) for () production at TeV
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