Abstract: A traffic monitoring system includes many monitoring nodes (10) distributed along many roads. A sonar ranging module (12) in each node continually measures the height of vehicles (19) crossing thereunder with repeated sonar pulses. A microcontroller (14) contains suitable instructions for estimating the speed of the vehicle by assigning a length to the vehicle based on its measured height, and dividing the length by the crossing time that the vehicle took to cross under the sonar module. The speed information from each node is transmitted to a central station (11) via a communication link (17). In a second embodiment, each node (10A) includes a pair of sonar modules (12A) spaced apart along a road. These measures the height of the vehicle, as well as the traversal time it takes to travel between both sonar modules. The microcontroller (14A) contains suitable instructions for dividing the modules' separation distance by the traversal time to accurately calculate the speed of the vehicle.

Abstract: This invention is directed towards a scalable X-ray laser comprising means for providing an active medium of lithium-like atoms or ions, means for producing in the active medium a population of low density ions in an excited intermediate metastable state and a visible or near infrared laser to stimulate X-ray lasing by resonant or non-resonant antistokes Raman process to the ground state of the ions. The irradiation of the ions by the laser provides phased or traveling wave excitation which produces the desired directivity. Production of the metastable state is provided by directing energy from a suitable source, such as a high power short pulse laser beam, onto a target material and causing it to radiate as a black body, filtering this radiation to derive radiation in the soft X-ray region, and directing this filtered radiation into the lithium-like vapor.