Experimental measurements of the second order susceptibilities for the second harmonic generation are reported for YAl3(BO3)4 (YAB) single crystals for the two principal tensor components xyz and yyy. First principle's calculation of the linear and nonlinear optical susceptibilities for Yttrium Aluminum Borate YAl3(BO3)4 (YAB) crystal have been carried out within a framework of the full-potenti...

We propose Imaginary Devices, a set of freehand gestures that mimic the use of physical input devices. Imaginary Devices allow users to choose the input modality best suited for the task at hand, such as a steering wheel for a driving game or a joystick for a flight simulator. Exploiting the skills that users have acquired using physical input devices, they can instantly begin interacting with ...

Leaders today seem to be suffering from what might be called a failure of the imagination. We seem to be continually finding ourselves in situations where the leaders say something like “no one could have imagined that this would happen.” For example: Who could imagined that Hurricane Katrina would breach the levies in New Orleans; who could have imagined that an insurgency would arise from the...

Vanderbauwhede and van Gils, Krupa, and Langford studied unfoldings of bifurcations with purely imaginary eigenvalues and a nonsemisimple linearization, which generically occurs in codimension three. In networks of identical coupled ODE these nilpotent Hopf bifurcations can occur in codimension one. Elmhirst and Golubitsky showed that these bifurcations can lead to surprising branching patterns...

Abstract This paper presents a solution to a superoptimal version of the block AAK problem Given a rational and antistable matrix function R s R s R s and a nonnegative integer k nd all superoptimal approximations Q s with no more than k poles in the right half complex plane that minimise the supremum over the imaginary axis of the singular values of the error function E s R s R s Q s with resp...

The axiom of choice, a benign matter for the non-logician, puzzles mathematicians. Today, it manifests itself in a strange way: it takes, depending on the axiom’s variants, either two or infinity of colors to resolve a coloring problem. Just as the parallels postulate seemed obvious, the axiom of choice has often been considered true and beyond discussion. The inventor of set theory, Georg Cant...