in this paper, the lorentzian version of beltrami-euler formula is investigated in 1n . initially,the first fundamental form and the metric coefficients of generalized timelike ruled surface are calculated and by the help of the christoffel symbols, riemann-christoffel curvatures are obtained. thus, the curvatures of spacelike and timelike tangential sections of generalized timelike ruled surf...

In the current research with novel first and second differentiations of a yield function, Euler forward along with Euler backward with its consistent elastic-plastic modulus are newly implemented in finite element program in rate-independent plasticity. An elastic-plastic internally pressurized thick walled cylinder is analyzed with four famous criteria including both pressure dependent and ind...

a tiling of a surface is a decomposition of the surface into pieces, i.e. tiles, which cover it without gaps or overlaps. in this paper some special polygonal tiling of sphere, ellipsoid, cylinder, and torus as the most abundant shapes of fullerenes are investigated.

depth estimation of the top of the bedrock in the sedimentary basins is the main goal in geomagnetic explorations. the depth estimation of this kind of anomalies can be done using different methods, in the cases where the bedrock is magnetized. in this article, we use the standard euler deconvolution method and its results to interpret the magnetic data from the reshm region in semnan province ...

By Euler integration we mean the integration of definable functions on R against the Euler characteristic. We investigate the structure of the ring of all definable functions (with compact support respectively), the multiplication being defined by the convolution with respect to the Euler integration.

the euler-lagrange equation plays an important role in the minimization problems of the calculus of variations. this paper employs the differential transformation method (dtm) for finding the solution of the euler-lagrange equation which arise from problems of calculus of variations. dtm provides an analytical solution in the form of an infinite power series with easily computable components. s...

an internal ballistics model has been developed for performance prediction of a solid propellant rocket motor. inthis model a 1-d unsteady euler equation with source terms is considered. the flow is assumed as a non-reacting mixture of perfect gases with space and time varying thermo physical properties. the governing equations in the combustion chamber are solved numerically by using the stege...

numerical analyses have shown that successful flow simulations and the accuracy of solution noticeably depend on the number of nodes used in computational meshing. a suitable meshing should have the capability of adapting with main flow parameters. because the number of total nodes that can be used in numerical simulation is limited, making such grid for complex flows is almost difficult, if it...