Of all the flight modes of unmanned aerial vehicles (UAVs), the landing approach and the landing itself are the most difficult and dangerous ones. To perform an automatic landing on a ship deck using a computer vision system (CVS), a UAV must analyze the visual landing markers located on the deck. When the UAV is about to start landing, these markers must be clearly visible and discernible. The...

Overhead persistent surveillance systems are becoming more capable at acquiring wide-field image sequences for long time-spans. The need to exploit this data is becoming ever greater. The ability to track a single vehicle of interest or to track all the observable vehicles, which may number in the thousands, over large, cluttered regions while they persist in the imagery either in real-time or ...

Due to their potential applications for optical communications, data storage, and electrooptical signal processing, molecules with nonlinear optical (NLO) properties have been extensively investigated.’ As part of our interest in porphyrins and metalloporphyrins as photoresponsive2 and field-responsive material^,^ we have synthesized a series of “push-pull” porphyrins containing both donor and ...

The electric birefringence technique was used to investigate the steady-state birefringence, the orientational relaxation time, and the orientation mechanism of pig heart mitochondrial F1 adenosine-5'-triphosphatase (F1-ATPase). The electrooptical properties of this enzyme in solution were studied as functions of pH, protein concentration, and applied electric field. The F1-ATPase exhibits a su...

A new bent-core mesogen combining a 4-cyanoresorcinol unit with two terephthalate based rod-like wings and terminated by two long alkyl chains, was synthesized and investigated by DSC, XRD, optical, electrooptical and dielectric methods. A series of liquid crystalline phases in the unique sequence SmA-SmA(P)-SmCPR-(M1/SmCPα)-SmCsPA-SmCPA-SmCaPA, mainly distinguished by the degree and mode of co...