There is clearly no increase in their frequency, even as the total number of reported tornadoes has more than doubled with radar detection.
The Type 056 stealth frigate has a sleek design that helps it evade radar detection, and needs just one-third of the crew used by its predecessor.
These include GPS, stereo cameras, radar and Light Detection and Ranging (LIDAR) laser tracking.
In 1935, RADAR (Radio Detection and Ranging) was first demonstrated by Robert Watson-Watt.
Rare earth elements are also used for military applications, such as advanced optics technologies, radar and radiation detection equipment, and advanced communications systems, according to a 2011 research report by the US Government Accountability Office.
The Russian president has offered a Russian radar in Azerbaijan as an alternative to the detection and tracking radar slated under the Bush plan for the Czech Republic.
In the mid-1980s, American intelligence discovered a huge missile- detection and -tracking radar being built by the Soviet Union near the Western Siberian town of Krasnoyarsk.
Like its cousins radar and sonar, lidar (light detection and ranging), works by broadcasting electromagnetic waves towards a target and then building up a picture from the reflection.
This passive-detection scheme has several advantages over conventional radar.
By incorporating a commercial radar (the Cerberus Scout surveillance system), target detection reached 100 percent.
Ford's prototype system aims to lessen distraction by taking readouts from biometric sensors and combining the data with information from the car, including speed, steering-wheel angle, and data from radar sensors or cameras used in blind-spot obstacle detection or cruise control.
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Within a few years, the lab developed radar systems used for naval navigation, weather prediction, and the detection of bombers and U-boats.
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