原文已被隐藏，你可用 快捷键 - 或点击 显示原文 按钮来查看原文
第1段
1 .This is Scientific American 60-Second Science. I'm Christopher Intagliata. Got a minute?
该句暂无译文！
2 .When the first shots were fired at JFK's motorcade, police couldn't immediately locate the gunman based on sound alone.
该句暂无译文！
3 .Today, the technology exists for them to it with their smartphones, less than a second after the first shot.
该句暂无译文！
4 .Here's how.
该句暂无译文！
5 .Most bullets travel at supersonic speeds, generating a shock wave along their path.
该句暂无译文！
6 .To track that path, researchers built a small bluetooth sensor for smartphones.
该句暂无译文！
7 .The sensor uses four mics to measure the shock wave's angle, and its time of arrival.
该句暂无译文！
8 .Then each phone networks with nearby phones to triangulate the sniper's location, mapping it on the smartphone screen within a second of the gun blast.
该句暂无译文！
9 .Researchers tested the system with an AK-47, and were able to calculate the shooter's bearings with less than seven degrees of error, and get a decent estimate of his range.
该句暂无译文！
10 .They presented the method at the Conference on Information Processing in Sensor Networks in Philadelphia.
该句暂无译文！
11 .Since the system requires at least two phones to work, researchers say it would be ideal for a security force fanned out around a likely target,
该句暂无译文！
12 .allowing them to respond to threats almost as fast as a speeding bullet.
该句暂无译文！
13 .Thanks for the minute, for Scientific American 60-Second Science. I'm Christopher Intagliata.
该句暂无译文！