We describe a class of logically rectangular quadrilateral and hexahedral grids for solving PDEs in circular and spherical domains, including grid mappings for the circle, the surface of the sphere, and the three-dimensional ball. The grids are logically rectangular and the computational domain is a single Cartesian grid. Compared to alternative approaches based on a multiblock data structure o...

Clustering is a key data mining problem. Densitybased clustering algorithms have recently gained popularity in the data mining field. Density and grid based technique is a popular way to mine clusters in a large spatial datasets wherein clusters are regarded as dense regions than their surroundings. The attribute values and ranges of these attributes characterize the clusters In this paper we a...

SUMMARY In this paper, we present self-avoiding walks as a novel technique to \linearize" an unstructured mesh. Unlike space-lling curves which are based on a geometric embedding, our strategy is combinatorial since it uses the mesh connectivity only. We formulate a linear time-complexity algorithm for the construction of these self-avoiding walks over a triangular mesh. We also show how the co...

In this paper, we study the stability and accuracy of adaptive finite element methods for the convection-dominated convection-diffusion-reaction problem in the twodimension space. Through various numerical examples on a type of layer-adapted grids (Shishkin grids), we show that the mesh adaptivity driven by accuracy alone cannot stabilize the scheme in all cases. Furthermore the numerical appro...

existed electricity grids deliver produced power to the consumer passing through transmission and distribution grids. according to high losses of these grids in transmission level and inexistence of bilateral interaction for simultaneous information exchange, a concept of smart grids were made by capabilities such as consciously participation of consumers in the smart electricity grids, an amou...