Given an instance I of a minimization problem with optimum opt, fixed parameter ρ(k) inapproximability is to find a k ≥ opt and prove that it is not possible to compute a solution of value ρ(k) · k usually under the eth. In this paper we are interested only in k being the optimum value of some instance. Our question is: What properties make a good Fixed Parameter Inapproximability proof? We cla...

This study presents the effect of edge ratio and fiber orientation on free vibration analysis of simply supported antisymmetric thin and thick laminated composite plates (LCP) on elastic foundation. In the analysis, the foundation is modeled as two parameters Pasternak and Winkler type foundation. The equation of motion for laminated rectangular plates resting on elastic foundation is obtained ...

The new version of differential quadrature (DQ) method is extended to analyze the free vibration of thin sector orthotropic plates on the Pasternak elastic foundation with various sector angles and elastic parameters. Detailed formulations are given. Comparisons are made with existing analytical and/or numerical data. Numerical results indicate that convergence can be achieved with increasing i...

A master element to be employed as a general spatial rod finite element is presented. This spatially curved and pretwisted element can have variable cross-section and variable curvature change. It may also be resting on an elastic foundation. Also, a finite element formulation for a general earthquake analysis of spatial rods is presented. The theoretical foundation has lead to a general-purpos...

Because of difficulty in inspection and retrofit of foundation in comparison with other elements, the common design philosophy is to avoid any nonlinear deformation in the foundation. This paper shows that by employing controlled foundation nonlinearity, in predetermined sections with arrangements for inspection and retrofit, it is possible to reduce seismic demand on superstructure. Localizing...