The orbital instability of ground state standing waves eφω(x) for the nonlinear Klein-Gordon equation has been known in the domain of all frequencies ω for the supercritical case and for frequencies strictly less than a critical frequency ωc in the subcritical case. We prove the strong instability of ground state standing waves for the entire domain above. For the case when the frequency is equ...

This paper seeks to address the issue of weak and strong sustainability as well as the search for a middle ground. It discusses the differences between weak and strong sustainability while arguing for the harmonisation of both nature and humankind. Achieving harmony requires a move towards an idealist eco-sociofeminist point of view. Through this, full equality and balance may be attained.

Abstract: Since soil dynamic behaviour is nonlinear in nature therefore a nonlinear viscoelastic model for isotropic materials is proposed in this study. This model is a combination of inelasticity and nonlinear damping. In this model, the shear modulus is taken as a function of the excitation level. The viscosity is assumed to vary nonlinearly. The validity of this model is checked for low amp...