ABSTRM'I. This work is devoted to the analysis of a class of nonlinear shallow shell problems. First we recall the classical nonlinear shallow shell equations of W. T. Koiter b'lsed on a representation of the middle surface of the shell by a general system of curvilinear coordinates. Next. we prove an e~istencc Theorem for solutions of these equations using the theory of pseudo,monotone operalo...

In this paper, the radial breathing mode (RBM) frequencies of multi-walled carbon nanotubes (MWCNTs) are  obtained based on the multiple-elastic thin shell model. For this purpose, MWCNT is considered as a multiple concentric elastic thin cylindrical shells, which are coupled through van der Waals (vdW) forces between two adjacent tubes. Lennard-Jones potential is used to calculate the vdW ...

Correlated basis function theory and Fermi hypernetted chain theory are extended to treat finite Fermi systems . In this first paper, the effects of the scalar nucleon-nucleon correlations are investigated by studying some model N = Z nuclei . Results of calculations performed using central nucleon-nucleon potentials, without tensor components, are presented and are compared with results from o...

This paper presents the study on influence external pressures on vibration of functionally graded materials thin-walled cylindrical shell supported. The functionally graded materials (FGMs) properties are graded in the thickness direction of the shell. FGMs are advanced composite materials, consisting of different types of materials, in which the properties shift continuously from one material ...

Koiter’s linear shell theory applies to isotropic elastic materials and to anisotropic materials that exhibit reflection symmetry of the elastic properties with respect to the shell midsurface. To the extent that such shells are exceptional, classical linear shell theory is incomplete. This lacuna is addressed here through a systematic procedure, applicable equally to all kinds of material symm...

We analyze the structure of the Föppl-von Kármán shell equations of linear elastic shell theory using surface geometry and classical invariant theory. This equation describes the buckling of a thin shell subjected to a compressive load. In particular, we analyze the role of polarized Hessian covariant, also known as second transvectant, in linear elastic shell theory and its connection to minim...

The one-dimensional harmonic oscillator in a box problem is used to introduce the concept of an oblique-basis shell-model theory. The method is applied to nuclei by combining traditional spherical shell-model states with SU(3) collective configurations. An application to Mg, using the realistic two-body interaction of Wildenthal, is used to explore the validity of this oblique-basis, mixed-symm...

We study gauge invariant operators of open string field theory and find a precise correspondence with on-shell closed strings. We provide a detailed proof of the gauge invariance of the operators and a heuristic interpretation of their correlation functions in terms of on-shell scattering amplitudes of closed strings. We also comment on the implications of these operators to vacuum string field...

We propose to determine the coefficients in the Fermilab heavy quark action by matching the finite-volume, off-shell, gauge-fixed propagator and vertex functions with those determined in the exact, relativistic theory. The matching relativistic amplitudes may be determined either from short-distance perturbation theory or from finite-volume step-scaling recursion. Tree-level matching and non-pe...