A train needs friction between its wheels and the rail’s upper surface in order to move, but friction between the wheel and the sides of the rails is a different matter. Over time, the stress from this friction, especially as trains go around curves, can cause rails to crack; sometimes train wheels even climb over the sides of tracks and derail. The railroad industry combats this problem by applying lubricant to rails, but it’s far from a perfect solution: The environmentally unfriendly stuff seeps into the ground and sometimes spreads to the rail tops, making them slippery. Researchers at Argonne National Laboratory in Argonne, Ill., are using a laser to rapidly melt and re-solidify the steel on the side of the rail. This “glazing “creates a slippery surface that is also more durable. Although research is still in its early stages, principal investigator Ron DiMelfi estimates that laser glazing could save the U.S. railroad industry $40 million per year on fuel and $16 million per year on rail replacements.
Geoffrey Hinton tells us why he’s now scared of the tech he helped build
“I have suddenly switched my views on whether these things are going to be more intelligent than us.”
Deep learning pioneer Geoffrey Hinton has quit Google
Hinton will be speaking at EmTech Digital on Wednesday.
Video: Geoffrey Hinton talks about the “existential threat” of AI
Watch Hinton speak with Will Douglas Heaven, MIT Technology Review’s senior editor for AI, at EmTech Digital.
Doctors have performed brain surgery on a fetus in one of the first operations of its kind
A baby girl who developed a life-threatening brain condition was successfully treated before she was born—and is now a healthy seven-week-old.
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