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DIY Emergency Button: Hack a Nike + iPod Sport Kit to Create an Elder-Alert System

Some inexpensive components can replace pricey commercial services

4 min read
My mother could wear the tiny transmitter on a chain around her neck.
Photo: David Schneider

When my elderly mother moved into a nearby retirement community last year, I urged her to get a wearable alert bracelet. This would let her summon help should she, say, fall and be unable to get up or reach a phone. She signed on for one offered by her retirement community—and was given a device that’s as bulky as a can of tuna. She never wears it, and I don’t blame her.

There is actually a wealth of devices available to satisfy this emergency function, which is becoming increasingly important as the population ages. Many have a base station that attaches to a landline. Others have built-in GPS and cellular connections and can work away from home. The rub is that these devices are tied into services that tend to be pricey—typically US $30 or more a month. While my dear mother’s well-being is, of course, worth every penny of that, I didn’t see the need to spend so much on what I figured I could replicate for far less.

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From WinZips to Cat GIFs, Jacob Ziv’s Algorithms Have Powered Decades of Compression

The lossless-compression pioneer received the 2021 IEEE Medal of Honor

11 min read
Photo of Jacob Ziv
Photo: Rami Shlush

Lossless data compression seems a bit like a magic trick. Its cousin, lossy compression, is easier to comprehend. Lossy algorithms are used to get music into the popular MP3 format and turn a digital image into a standard JPEG file. They do this by selectively removing bits, taking what scientists know about the way we see and hear to determine which bits we'd least miss. But no one can make the case that the resulting file is a perfect replica of the original.

Not so with lossless data compression. Bits do disappear, making the data file dramatically smaller and thus easier to store and transmit. The important difference is that the bits reappear on command. It's as if the bits are rabbits in a magician's act, disappearing and then reappearing from inside a hat at the wave of a wand.

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