Let Pn be a pentagonal chain with 2n pentagons in which two edges common can regarded as adding one vertex and to hexagon. Thus, the linear derivation chains QPn represent graph obtained by attaching four-membered rings every of Pn. In this article, Laplacian spectrum consisting eigenvalues symmetric matrices is determined. Next, formulas for invariants that represented spectrum, namely, Kirchh...

A class of Kirchhoff type systems with nonlinear boundary conditions considered in this paper. By using the method of Nehari manifold, it is proved that the system possesses two nontrivial nonnegative solutions if the parameters are small enough.

This paper deals with the existence and multiplicity of solutions for a perturbed nonlocal fourth-order class p(·)&q(·)-Kirchhoff elliptic systems under Navier boundary conditions. By using variational method Ricceri’s critical point theorem, we can find proper conditions to ensure that (p(x),q(x))-Kirchhoff has at least three weak solutions. We have extended improved some recent results. T...

in exploration seismology, migration refers to a multi-channel processing step that attempts to spatially re-position events and improve focusing. before migration, seismic data is usually displayed with traces plotted at the surface location of the receivers and with a vertical time axis. this means that dipping reflections are systematically mispositioned in the lateral coordinate and the ver...

A new approach is presented for converting the surface integral, representing the Kirchhoff diffracted field of an aperture on a plane screen, to a line integral. It has the advantages that it is mathematically rigorous and explicit and that it results in a representation that has exactly the same properties as the original Kirchhoff formula, i.e., it admits arbitrary source distributions and i...

We discuss the Kirchhoff gauge in classical electrodynamics. In this gauge the scalar potential satisfies an elliptical equation and the vector potential satisfies a wave equation with a nonlocal source. We find the solutions of both equations and show that, despite of the unphysical character of the scalar potential, the electric and magnetic fields obtained from the scalar and vector potentia...

Helical configurations of inhomogeneous symmetric rods with non-constant bending and twisting stiffness are studied within the framework of the Kirchhoff rod model. From the static Kirchhoff equations, we obtain a set of differential equations for the curvature and torsion of the centerline of the rod and the Lancret’s theorem is used to find helical solutions. We obtain a free standing helical...