376801
Airport Surface Detection Equipment , Model X , or ASDE-X , is a runway - safety tool that enables air traffic controller s to detect potential runway conflicts by providing detailed coverage of movement on runways and taxiway s. By collecting data from a variety of sources , ASDE-X is able to track vehicles and aircraft on airport surfaces and obtain identification information from aircraft transponder s. Operation Originally the FAA installed 38 ASDE-3A radar systems at the nation 's busiest airports .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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