1,426 research outputs found
Spectral properties and pattern selection in fractal growth networks
A model for the generation of fractal growth networks in Euclidean spaces of
arbitrary dimension is presented. These networks are considered as the spatial
support of reaction-diffusion and pattern formation processes. The local
dynamics at the nodes of a fractal growth network is given by a nonlinear map,
giving raise to a coupled map system. The coupling is described by a matrix
whose eigenvectors constitute a basis on which spatial patterns on fractal
growth networks can be expressed by linear combination. The spectrum of
eigenvalues the coupling matrix exhibits a nonuniform distribution that is
reflected in the presence of gaps or niches in the boundaries of stability of
the synchronized states on the space of parameters of the system. These gaps
allow for the selection of specific spatial patterns by appropriately varying
the parameters of the system.Comment: 9 pages, 6 Figs, Submitted to Physica
Spectral Properties and Synchronization in Coupled Map Lattices
Spectral properties of Coupled Map Lattices are described. Conditions for the
stability of spatially homogeneous chaotic solutions are derived using linear
stability analysis. Global stability analysis results are also presented. The
analytical results are supplemented with numerical examples. The quadratic map
is used for the site dynamics with different coupling schemes such as global
coupling, nearest neighbor coupling, intermediate range coupling, random
coupling, small world coupling and scale free coupling.Comment: 10 pages with 15 figures (Postscript), REVTEX format. To appear in
PR
Microscopic approach to large-amplitude deformation dynamics with local QRPA inertial masses
We have developed a new method for determining microscopically the
fivedimensional quadrupole collective Hamiltonian, on the basis of the
adiabatic self-consistent collective coordinate method. This method consists of
the constrained Hartree-Fock-Bogoliubov (HFB) equation and the local QRPA
(LQRPA) equations, which are an extension of the usual QRPA (quasiparticle
random phase approximation) to non-HFB-equilibrium points, on top of the CHFB
states. One of the advantages of our method is that the inertial functions
calculated with this method contain the contributions of the time-odd
components of the mean field, which are ignored in the widely-used cranking
formula. We illustrate usefulness of our method by applying to oblate-prolate
shape coexistence in 72Kr and shape phase transition in neutron-rich Cr
isotopes around N=40.Comment: 6pages, talk given at Rutherford Centennial Conference on Nuclear
Physics, 8 - 12 August 2011, The University of Mancheste
A simulation framework for UAV sensor fusion
Proceedings of: 5th International Conference, HAIS 2010, San Sebastián, Spain, June 23-25, 2010.he behavior recognition is one of the most prolific lines of research in recent decades in the field of computer vision. Within this field, the majority of researches have focused on the recognition of the activities carried out by a single individual, however this paper deals with the problem of recognizing the behavior of a group of individuals, in which relations between the component elements are of great importance. For this purpose it is exposed a new representation that concentrates all necessary information concerning relations peer to peer present in the group, and the semantics of the different groups formed by individuals and training (or structure) of each one of them. The work is presented with the dataset created in CVBASE06 dealing the European handballThis work was supported in part by Projects ATLANTIDA, CICYT TIN2008-06742-
C02-02/TSI, CICYT TEC2008-06732-C02-02/TEC, SINPROB, CAM CONTEXTS
S2009/TIC-1485 and DPS2008-07029-C02-02.Publicad
Pattern Formation on Trees
Networks having the geometry and the connectivity of trees are considered as
the spatial support of spatiotemporal dynamical processes. A tree is
characterized by two parameters: its ramification and its depth. The local
dynamics at the nodes of a tree is described by a nonlinear map, given rise to
a coupled map lattice system. The coupling is expressed by a matrix whose
eigenvectors constitute a basis on which spatial patterns on trees can be
expressed by linear combination. The spectrum of eigenvalues of the coupling
matrix exhibit a nonuniform distribution which manifest itself in the
bifurcation structure of the spatially synchronized modes. These models may
describe reaction-diffusion processes and several other phenomena occurring on
heterogeneous media with hierarchical structure.Comment: Submitted to Phys. Rev. E, 15 pages, 9 fig
Phase ordering induced by defects in chaotic bistable media
The phase ordering dynamics of coupled chaotic bistable maps on lattices with
defects is investigated. The statistical properties of the system are
characterized by means of the average normalized size of spatial domains of
equivalent spin variables that define the phases. It is found that spatial
defects can induce the formation of domains in bistable spatiotemporal systems.
The minimum distance between defects acts as parameter for a transition from a
homogeneous state to a heterogeneous regime where two phases coexist The
critical exponent of this transition also exhibits a transition when the
coupling is increased, indicating the presence of a new class of domain where
both phases coexist forming a chessboard pattern.Comment: 3 pages, 3 figures, Accepted in European Physics Journa
Evaluation of Phyllanthus amarus herb for its hepatic effects
Aqueous extract of pulverized whole Phyllanthus amarus was assessed for hepatic effects in albino rats. Its phytochemical, proximate and mineral constituents were also evaluated. The results showed that the extract significantly reduced the plasma activities of alanine and aspartate transaminases and total bilirubin concentration (P < 0.01), with a non- significant increase in the plasma concentration of total protein (P > 0.01). The extract contained 24.05 % saponins, 17.50% tannins and 5.47 % oxalates as well as 11.05 % moisture, 6.80 % ash, 6.03 % fat, 6.10 % protein, 24.50 % fibre and 45.52 % carbohydrate. The mineral content of the defatted pulverized P. amarus was found to be potassium (150.30), sodium (228.20), calcium (1.60), magnesium (2.40), iron (1.65), and phosphorus (1.00) mg per 100 g dry weight. The reduction of plasma activity of transaminases and concentration of total bilirubin, with a concomitant increase in total protein concentration suggest that the plant has a hepatic cell protection function and enhancement potential. The high saponin and tannin, potassium and sodium, and carbohydrate and fibre contents of the plant explain its use in folk medicine for the treatment of liver problems, oedema and use as tonic, respectively.
Keywords: Phyllanthus amarus, Chemical Composition, Hepatic Effects, Albino Rat
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