singular perturbation problems have been studied by many mathematicians. since the approximate solutions of these problems are as the sum of internal solution (boundary layer area) and external ones, the formation or non-formation of boundary layers should be specified. this paper, investigates this issue for a singular perturbation problem including a first order differential equation with gen...

‎in this paper‎, ‎we consider an inverse boundary value problem for two-dimensional heat equation in an annular domain‎. ‎this problem consists of determining the temperature on the interior boundary curve from the cauchy data (boundary temperature and heat flux) on the exterior boundary curve‎. ‎to this end‎, ‎the boundary integral equation method is used‎. ‎since the resulting system of linea...

The hind limb of the lectotype Alectrosaurus olseni is described in comparison with other tyrannosauroids. In addition to autapomorphies for by previous workers, taxon possesses a specialized pes, where distal condyles metatarsals and most phalanges are strongly elevated beyond dorsal ventral surfaces shaft each bone, here as ‘pediculate’ condition. lectotype, previously reported Tyrannosaurus ...

The Cretaceous family Spathiopterygidae (Hymenoptera: Diaprioidea), containing five species in four genera, showed a wide distribution from the upper Barremian to Turonian. We describe two new representatives of Albian San Just outcrop eastern Iberian Peninsula that correspond Diameneura marveni gen. et sp. nov. Santer and Álvarez-Parra female member Mymaropsis turolensis Engel Ortega-Blanco, 2...

the isogeometric analysis is increasingly used in various engineering problems. it is based on non-uniform rational b-splines (nurbs) basis function applied for the solution field approximation and the geometry description. one of the major concerns with this method is finding an efficient approach to impose essential boundary conditions, especially for inhomogeneous boundaries. the main contri...

a lattice boltzmann method is applied to demonstrate the comparison results of simulating natural convection in an open end cavity using different hydrodynamic and thermal boundary conditions. the prandtl number in the present simulation is 0.71, rayleigh numbers are 104,105 and 106 and viscosities are selected 0.02 and 0.05. on-grid bounce-back method with first-order accuracy and non-slip met...