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Each had until 2018 a range of 256 km (159 mi) in radius around the site to detect reflectivity, 3 angles with a range of 128 km (80 mi), for detecting velocity pattern (Doppler effect), and an extra long range up to 240 km (150 mi) at low elevation angle but strongly folded or aliased (where the maximum unambiguous velocity interval (±Vmax ...
Pulse-Doppler radar and Continuous-wave radar are required for high performance in this area because these exclude low-velocity reflections. This is a critical measure of performance for the Littoral zone and land-based radar. Prevailing winds of about 15 mile/hour cover most of the surface of the earth. This constantly stirs up debris into the ...
The minimum railway curve radius is the shortest allowable design radius for the centerline of railway tracks under a particular set of conditions. It has an important bearing on construction costs and operating costs and, in combination with superelevation (difference in elevation of the two rails) in the case of train tracks , determines the ...
It is a unique ID number or code assigned to a package or parcel. The tracking number is typically printed on the shipping label as a bar code that can be scanned by anyone with a bar code reader or smartphone. In the United States, some of the carriers using tracking numbers include UPS, [1] FedEx, [2] and the United States Postal Service. [3]
In July 2010, SpaceQuest and exactEarth of Canada announced an arrangement whereby data from AprizeSat-3 and AprizeSat-4 would be incorporated into the exactEarth system and made available worldwide as part of their exactAIS(TM)service. On July 12, 2010, the Norwegian AISSat-1 satellite was successfully launched into polar orbit.
If the radar was locked on to the aircraft, it will hopefully remain locked to this second pulse as the aircraft moves away from the original location. Eventually, the aircraft will fall outside the range gate and disappear, while the radar continues tracking the false signal. Thus, the false signal is said to "pull the range gate off the target".
A surveyor uses a GNSS receiver with an RTK solution to accurately locate a parking stripe for a topographic survey. Real-time kinematic positioning (RTK) is the application of surveying to correct for common errors in current satellite navigation (GNSS) systems. [1]
The HARPS can attain a precision of 0.97 m/s (3.5 km/h), [2] making it one of only two instruments worldwide with such accuracy. [citation needed] This is due to a design in which the target star and a reference spectrum from a thorium lamp are observed simultaneously using two identical optic fibre feeds, and to careful attention to mechanical stability: the instrument sits in a vacuum vessel ...