标签: electricity

Here's another post, in which we pause for a moment to take a deep breath (hold it... hold it... now exhale), slow down, relax, and start winding down in preparation for the weekend. As part of this exercise, I've gathered a few choice diversions for your delectation, delight, pondering, and rumination. This week's humble offerings are as follows: No. 1: Do you think you are having a bad day? Is it as bad as sending eye-watering amounts of electricity surging through your tongue? Sometimes, no matter how horrifying a video is, you just cannot look away. ( Click here to discover more.) No. 2: Unfortunately, Mehdi Sadaghdar—the star of the previous video—just doesn't know when to stop. His videos on how to change an electric light bulb ( click here ) and how to build an electric guitar ( click here ) cannot fail to make you cringe and wince with empathetic pain. No. 3: I don't know about you, but my eyes are still watering from the previous videos. Let's change pace and look at something that makes one gasp in wonder—a 240-year-old clockwork automaton that can write. ( Click here to discover more.) No. 4: Now I feel in the mood for the video equivalent of comfort food. One of my all-time favourite videos is the trick the Improv Everywhere group played in Grand Central Station. Even if you've seen this before, it's always worth another look. ( Click here to discover more.) No. 5: Speaking of improv, another of my all-time favourite videos is the one where over 200 dancers perform "Do, Re, Mi," from The Sound of Music in a Belgian train station. Once again, even if you've already seen this, you need to watch it again, because it's simply impossible to view this all the way through without ending up with a great big beaming smile on your face. ( Click here to discover more.) As usual, if you know of any interesting sites you'd care to share, please comment below.  

We recently lost electricity at the house. I am sure this an experience you have all had. When the power came back on a few hours later (what a relief), it was as if the house had come alive—both figuratively and literally. I say this because as power came back, there were all sorts of "hello, I'm here" beeps and sounds emanating from every corner, from the PCs, the printer, the cordless phones, the TV, the VCR (yes, we still have that!), the answering machine, the microwave, the stove, the cable modem, various clocks, and more. It was as if each of these had just been born, and was demanding parental attention. And some of them really needed it: there were clocks to reset, PCs to reinitialize, settings to restore; the list went on. As I went around taking care of them, all I could think of was Mary Shelley's classic book Frankenstein where the protagonist of the title creates artificial life, who we have come to know as the "monster" (don't want to read the book? You can also enjoy the classic 1931 movie version with Boris Karloff). There's an eerie parallel between the house's awakening and the monster's: in the book, the monster is brought to life by a bolt of lightning which comes from a rod on the roof to the lab where the experiment is under way. Sounds sort of like having the AC mains come on, in a way.... The AC-power cycling was like a creature coming to life, for sure. But it also reminded me that engineers should fully, thoroughly exercise and verify random power-off/power-on cycling of their products for every operating mode and scenario. Most of us have seen products which crashed when power failed, and had to be manually power-cycled few times to restart them—and have even seen some which failed outright when the power failure or restart occurred at just the wrong moment. So I'll deal with my personal "creature" coming back to life, and you can help by doing thorough job of designing and checking the cycling of the ones with which you're involved, please. Even if your product has a back-up battery, it too can run down, of course, or need special consideration. Have you ever experienced "bad behavior" due to random power cycling?