An efficient C0 continuous two dimensional (2D) finite element (FE) model is developed based on a refined higher order shear deformation theory (RHSDT) for the static analysis of soft core sandwich plate having imperfections at the layer interfaces. In this (RHSDT) theory, the in-plane displacement field for the face sheets and the core is obtained by superposing a globally varying cubic displa...

Based on the size-dependent cohesive energy formula for two-dimensional materials, we investigate the gap openings in graphene layers regarding distinct interfacial interaction from substrates. Depending on the interfacial physicochemical nature, the gap is opened weakly induced by the van der Waals interaction but readily by the chemical bonding. Relative to the former, in essence, the distinc...

Gap between the steel tube and core concrete of Concrete-Filled Steel Tube (CFST) members is regarded as an initial imperfection, which may exist in CFST arch bridge due to construction process problems. In this paper, based on design scheme bolt-welded joints rib columns extra-long span bridge, effects two types imperfections, interfacial gap spherical-cap gap, mechanical properties Bolt-Welde...

An asymptotic method based plate analysis is carried out for composite laminates including interfacial imperfections. By scaling of the thickness coordinate with respect to the characteristic length of the plate, the initial three-dimensional governing equations are separated into the microscopic through-the-thickness equations and macroscopic plate equations. In the microscopic 1D analysis, fi...

One of the common failure modes of thin cylindrical shell subjected external pressure is buckling. The buckling pressure of these shell structures are dominantly affected by the geometrical imperfections present in the cylindrical shell which are very difficult to alleviate during manufacturing process. In this work, only three types of geometrical imperfection patterns are considered namely (a...

Perfect graphs constitute a well-studied graph class with a rich structure, reflected by many characterizations with respect to different concepts. Perfect graphs are, for instance, precisely those graphs G where the stable set polytope STAB(G) coincides with the fractional stable set polytope QSTAB(G). For all imperfect graphs G it holds that STAB(G) ⊂ QSTAB(G). It is, therefore, natural to us...

Because of their inherent abstraction, systems ideas are not themselves sufficient for gaining scientific knowledge or solving practical problems, but they can be a source of insights into the universality of imperfection, insights which can contribute to a new scientific world view. Systems theory offers a metaphysics, or more precisely an ontology, of imperfection. Through it, we can heed Spi...

We are interested in colouring a graph G=(V, E) together with an integral weight or demand vector x=(xv : v # V) in such a way that xv colours are assigned to each node v, adjacent nodes are coloured with disjoint sets of colours, and we use as few colours as possible. Such problems arise in the design of cellular communication systems, when radio channels must be assigned to transmitters to sa...