Biomedical subjects

Xiujun Fu

Publications and source records attributed to Xiujun Fu.

4 recordsLinked to original sources

PubMed2005

Effective elastic parameters of the two-dimensional phononic crystal.

The effective acoustic velocity along two highly symmetric directions of the first Brillouin zone is studied in a two-dimensional squarely arranged solid-solid phononic crystal. The relationship between the effective elastic velocity and the wave frequency of the two lowest bands is presented, which gives the same results as those obtained directly from the band structure. Numerical calculations show that the effective acoustic velocity of the phononic crystal decreases with frequency increasing from zero to the band edge.

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PubMed2004

Phase transition of two-dimensional Ising model on random point patterns.

The phase transition of two-dimensional Ising model on random point patterns is investigated using Monte Carlo simulation and the critical temperature is calculated using the Bethe approximation. We find a linear relation between the critical temperature and the structural characteristics of the random point pattern, as described by Aboav's parameter. Numerical results and analytical calculation both yield this linear relation with a similar slope, though the intercept is different due to the Bethe approximation.

Journal Article↗

PubMed2004

Damage spreading on two-dimensional trivalent structures with Glauber dynamics: hierarchical and random lattices.

The damage spreading of the Ising model on various two-dimensional trivalent structures with Glauber dynamics is investigated. It is shown that topology plays an important role in determining the damage spreading transition temperatures of the trivalent structures. When damage is considered in terms of only the topological properties of the cellular patterns, the transition temperature above which damage is saturated is found to be determined by the cells with the highest edge number. When the area of cells is also taken into account in the computation of damage, the damage spreading transition temperatures are all lowered. These results are verified by simulation on a set of hierarchical lattices constructed by recursive application of the star-triangle transformation on the vertices of the hexagonal structure, as well as soap froth and randomized lattice structures using Voronoi construction.

Journal Article↗

PubMed2002

Universal topological properties of two-dimensional trivalent cellular patterns.

Universal topological properties of two-dimensional trivalent cellular patterns are found from shell analysis of soap froth and computer-generated Voronoi diagrams. We introduce a cluster analysis based on the shell model and find the universal relation ln(a/mu(2)) = A+Bln(mu(2)), with the generalized Aboav parameter a and second moment of the number of cell edge distribution mu(2). For the second, third, and fourth shells of the cluster, A and B are the same for all samples. Furthermore, A is increasing with shell number while B is a universal number, -0.90. For the first shell, the slope B is the same for soap froths, but slightly different from Voronoi graphs.

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