'Nano-origami' reshapes liquid droplets into six-pointed stars

For the first time, researchers in France and Israel have observed how an emulsified liquid droplet can transform from a ...
IEEE

Entry Trajectory Optimization With General Polygonal No-Fly Zone Constraints

Abstract: Trajectory optimization of a hypersonic glide vehicle (HGV) has a highly nonlinear model and complex constraints. Therefore, it is difficult to deal with polygonal no-fly zone (PNFZ) ...
IEEE

A Convex Optimization Approach for the Design of Supergain Electrically Small Antenna and Rectenna Arrays Comprising Parasitic Reactively Loaded Elements

Abstract: A convex optimization formulation is provided for antenna arrays comprising reactively loaded parasitic elements. The objective function consists of maximizing the array gain, while ...
BBC

The lens power equation

\(power \ of \ a \ lens \ (D) = \frac{1}{focal \ length \ (m)}\) A lens has a power of -3.33 dioptres. Calculate the focal length and state what type of lens it is.