sandwich panels as composite materials have two external walls of either metallic or polymer type. the space between these walls is filled by hard foam or other materials and the thickness of different layers is based on the final application of the panel. in the present work, the extent of variation in core density of polyether urethane foam and subsequent flexural and compressive changes in s...

We study the local equivalence problem for real-analytic (Cω) hypersurfaces M5⊂C3 that, in some holomorphic coordinates (z1,z2,w)∈C3 with w=u+ −1v, are rigid sense that their graphing functions u=F(z1,z2,z‾1,z‾2) independent of v. Specifically, we group Holrigid(M) biholomorphic transformations form (z1,z2,w)⟼(f1(z1,z2),f2(z1,z2),aw+g(z1,z2)), where a∈R∖{0} and D(f1,f2)/D(z1,z2)≠0, which preser...

One of the important issues in the study of steel frames is to find a suitable formulation for semi-rigid connections. In this paper, the explicit stiffness matrix for a two-dimensional beam-column element having end-flexibilities is derived. The effects of the lateral uniformly distributed load on the deflection are considered. Both tensile and compressive axial loads are also taken into accou...

A flexible-joint robot manipulator is a complex system because it is nonlinear, multivariable, highly coupled along with joint flexibility and uncertainty. To overcome flexibility, several methods have been proposed based on flexible model. This paper presents a novel method for controlling flexible-joint robot manipulators. A novel control law is presented by compensating flexibility to form a...

A solution is presented to a doubly mixed boundary value problem of the torsion of an elastic layer, partially resting on a rigid circular base by a circular rigid punch attached to its surface. This problem is reduced to a system of dual integral equations using the Boussinesq stress functions and the Hankel integral transforms. With the help of the Gegenbauer expansion formula of the Bessel f...