Let D be a set of disks of arbitrary radii in the plane, and let P be a set of points. We study the following three problems: (i) Assuming P contains the set of center points of disks in D, find a minimum-cardinality subset P∗ of P (if exists), such that each disk in D is pierced by at least h points of P∗, where h is a given constant. We call this problem minimum h-piercing. (ii) Assuming P is...

The two-dimensional problem of time-harmonic water waves in the presence of a freely floating structure (it consists of a finite number of infinitely long surface-piercing cylinders connected above the water surface) is considered. The coupled spectral boundary value problem modeling the small-amplitude motion of this mechanical system involves the spectral parameter, the frequency of oscillati...

A simple and reliable computer code has been devised for evaluating various design parameters, and predicting the penetration performance of concrete piercing earth shock missile-warhead and will be useful to the designers of earth penetrating weapon system.

A cavity quantum electrodynamics (cavity-QED) system combines two or more distinct quantum components, exhibiting features not seen in the individual systems. In this work, we study the one-dimensional Jaynes-Cummings-Hubbard model in the two-excitation (two-polariton) subspace. We find that the centre momentum of two-excitation induces a magnetic flux piercing the equivalent Hamiltonian Hk in ...