I average 18mph (burst of up to 30mph) on a7 mile ride and I have never been unable to hear approaching cars from behind. Do I trust my ears alone? No. But I've never been surprised by Prius, Volt, Tesla Roadster, or any other hybrid or electric vehicles. In biking events or on bike paths I can even hear approaching bicycles from behind (bike chain, wind, and tire noise). So I'm surprised that wind noise overpowers car noises for you.
It's been interesting to see all the comments about this! Obviously it's struck a nerve...and danger aside, I'm happy to see a number of people less than thrilled about the idea of noisier hybrids and EVs. There has to be a better solution.
The 1865 act required all road locomotives, which included automobiles, to travel at a maximum of 4 mph (6 km/h) in the country and 2 mph (3 km/h) in towns and have a crew of three travel, one of whom should carry a red flag walking 60 yards (55 m) ahead of each vehicle.
Backup audible warning is already implemented on most trucks, commercial vehicles, municipal vehicles, etc. That is not a bad idea; the driver has limited view, and risk is higher. But that is totally different than always on noise generators.
These new 3D-printing technologies and printers include some that are truly boundary-breaking: a sophisticated new sub-$10,000, 10-plus materials bioprinter, the first industrial-strength silicone 3D-printing service, and a clever twist on 3D printing and thermoforming for making high-quality realistic models.
Ear-based heart-rate monitoring gained momentum recently, as sensor maker Valencell Inc. announced it has licensed its biometric earpiece technology to Samsung Electronics Co. Ltd for use in so-called “hearable devices.”
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies.
You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived.
So if you can't attend live, attend at your convenience.