In this paper we present a novel approach to shape similarity estimation. The target application is content-based indexing and retrieval over large image databases. The technique is based on wavelet decomposition and uses polygon approximation over several scales. This technique uses simple features (aspect ratio, angles, distances from the centroid, distance ratios and relative positions) extr...

To determine the magnification of an extended source caused by gravitational lensing one has to perform a two-dimensional integral over point-source magnifications in general. Since the point-source magnification jumps to an infinite value on caustics, special care is required. For a uniformly bright source, it has been shown earlier that the calculation simplifies if one determines the magnifi...

In the centrosymmetric title compound, C(12)H(10)O(2)S(2), the alkyl chains adopt a fully extended all-trans conformation with respect to the C(thio-phene)-C bond. The non-H atoms of the mol-ecule are nearly planar, with a maximum deviation of 0.063 (2) Å from the mean plane of the constituent atoms. In the crystal, symmetry-related mol-ecules are linked via pairs of C-H⋯π contacts [H-centroid ...

The formulation of quantum statistical mechanics based on the path centroid variable in Feynman path integration is generalized to a phase space perspective, thereby including the momentum as an independent dynamical variable. By virtue of this approach, operator averages and imaginary time correlation functions can be expressed in terms of an averaging over the multidimensional phase space cen...