The phononic band structures of two-dimensional solid phononic crystals with different lattice and scatterer symmetry are studied numerically, with three types of lattice (square, triangular and rectangular) and four different scatterer shapes (circle, hexagon, square and rectangle) considered. XY and Z vibration modes are investigated separately. Two types of phononic crystal are considered: o...

We develop the approach to the problem of integrable discretization based on the notion of r–matrix hierarchies. One of its basic features is the coincidence of Lax matrices of discretized systems with the Lax matrices of the underlying continuous time systems. A common feature of the discretizations obtained in this approach is non–locality. We demonstrate how to overcome this drawback. Namely...

Tadpole improved Wilson quark actions with clover terms on anisotropic lattices are studied numerically. Using asymmetric lattice volumes, the pseudo-scalar meson dispersion relations are measured for 8 lowest lattice momentum modes with quark mass values ranging from the strange to the charm quark with various values of the gauge coupling β and 3 different values of the bare speed of light par...

Discrete breathers are found in a nonlinear one dimensional axially loaded mechanical lattice consisting of rigid links supported laterally by linear springs. We find link centered breathers for an odd number of mechanical links and pivot centred breathers where the number of links is even. Substantial parameter regions in load–frequency parameter space are found where these breathers are linea...

We consider nite lattice coverings of strictly convex bodies K. For planar centrally symmetric K we characterize the nite arrangements Cn such that conv Cn Cn + K, where Cn is a subset of a covering lattice for K (which satisses some natural conditions). We prove that for a xed lattice the optimal arrangement (measured with the parametric density) is either a sausage, a socalled double sausage ...

A semiclassical model for studying charge transport in a two-dimensional molecular lattice is presented and applied to both a well ordered system and a system with disorder. The model includes both intra- and inter-molecular electron-lattice interactions and the focus of the studies is to describe the dynamics of a charge carrier in the system. In particular, we study the dynamics of the system...

We present the results of the numerical calculation of the probability distribution of the value of the monopole creation operator in SU (2) lattice gluodynamics. We work in the maximal abelian projection. It occurs that at the low temperature, below the deconfinement phase transition the maximum of the distribution is shifted from zero, which means that the effective constraint potential is of...

The coupled cluster method ~CCM! is applied to a spin-half model at zero temperature which interpolates between a triangular lattice antiferromagnet ~TAF! and a kagomé lattice antiferromagnet ~KAF!. The strength of the bonds which connect kagomé lattice sites is J, and the strength of the bonds which link the non-kagomé lattice sites to the kagomé lattice sites on an underlying triangular latti...

The infrared properties of lattice Landau gauge QCD of SU(3) are studied by measuring gluon propagator, ghost propagator, QCD running coupling and Kugo-Ojima parameter of β = 6.0, 16, 24, 32 and β = 6.4, 32, 48, 56 lattices. By the larger lattice measurements, we observe that the runnning coupling measured by the product of the gluon dressing function and the ghost dressing function squared res...

We present a determination of the QCD parameter Λ in the quenched approximation (nf = 0) and for two flavours (nf = 2) of light dynamical quarks. The calculations are performed on the lattice using O(a) improved Wilson fermions and include taking the continuum limit. We find Λ nf=0 = 259(1)(20)MeV and Λ nf=2 = 261(17)(26)MeV, using r0 = 0.467 fm to set the scale. Extrapolating our results to fi...