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265

Yes, and ReCaptcha have always been open about it, before and after being acquired by Google. From its formation, one of ReCaptcha's main selling points was that the data would be used. At first, it was used for fixing errors and ambiguities in the digitisation of books. Here's an example of this being praised back in 2007, 2 years before Google acquired it,...


129

There is not much to doubt here. This chip-art seems to have been either common practice or at least a wide spread in-joke among engineers: Steal the Best We stumbled across this message while examining the scribe lane on a Digital CVAX microprocessor used in the MicroVAX 3000 and 6200 series computers. Chip designer Bob Supnik tells us that ...


126

No, walls predate wheels by several millenia. The invention of the wheel is generally placed at around 3500-4500 BCE. However walls were famously built around the town of Jericho in 8000-9000BCE, so they are at least that old. More information can be found here: https://www.usatoday.com/story/news/politics/2019/01/10/president-trump-is-wheel-older-than-...


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Yes, GPS requires both general and special relativity to work [Note this is simplified account based on this and this (MS word download)] We can understand why by looking at how GPS actually determines where you are. The system relies on a number of satellites transmitting signals and your GPS device receiving those signals (see wikipedia). There are about ...


62

You can find information about this on Wikipedia ATM SafetyPIN software is a software application that would allow users of automated teller machines (ATMs) to alert the police of a forced cash withdrawal by entering their personal identification number (PIN) in reverse order.1 The system was invented and patented by Illinois lawyer Joseph ...


51

Most speakers really can work as microphones; the signal is weak, but it is there. See, for example, All speakers are microphones: What happens is that in a speaker there's a magnet and coil, and a pair of wires connecting it up to something. What is supposed to happen when the device is used for outputting sound that electricity is converted to sound. ...


48

There is actually some more detail on this on the Java website: 1.1 billion desktops run Java 930 million Java Runtime Environment downloads each year 3 billion mobile phones run Java 31 times more Java phones ship every year than Apple and Android combined 100% of all Blu-ray players run Java 1.4 billion Java Cards are manufactured each year ...


40

Yes! Luis von Ahn, one of original developers, talked in one TEDx conference about reCAPTCHA technology, and his new Project DuoLingo In this presentation, he talks about CAPTCHA history and problems and how people were wasting about 500,000 hours every day using CAPTCHA. Then he thought how use this time in a useful thing, like helping OCR books. He ...


39

For a TV to be able to interpret the information, the high-frequency input is mixed with a local oscillator signal. This is the signal that the detector van can pick up. Heaps more info here We have a very similar system in Sweden. The IT magazine Ny Teknik wrote an article called "Yes, you can detect flat screen TV's as well", to debunk the somewhat ...


36

It's unlikely that Apple's support for USB had any significant impact on the adoption of the standard. There are two other events that, in combination, "jump started" USB adoption. 1. Windows 98 release provides comprehensive USB support Windows 98 was released in June 1998. Prior to Windows 98, USB support in Windows was flaky at best. Support was ...


36

Yes, but this is a newly reported bug on OS X 10.8.4 and iOS 6.1.3 that affects CoreText API so it will likely be fixed in the near future. The text linked to is the same as appears in a screen shot on the Ars Technica article: The article then goes on to explain the following: There's a new bug in town, and it's here to crash your Mac and iPhone ...


34

UPDATE: Funny or Die have admitted that the video is a hoax on their site. Original answer: The "Huvr board" is most probably a hoax product. In addition to Jwenting's answer depicting the problem with the fact that a breakthrough technological achievement wasn't published in any form, professional, scientific or popular. Several sites on the internet ...


32

The video doesn't seem to be authentic. The video is used as a parody worldwide, it is international and labeled as a "video meme". The series of the meme is called : "El Risitas" Interview Parodies What the meme-creator does is the following: ignore the content of the video pick any subject prone to criticism create the fake subtitles (usually using a ...


32

The quoted statement says "energy to move a kilometer". On an "energy to move a kilometer" basis, the statement is definitely false. Acccording to Dr. Karen Oberhauser, a tagged monarch butterfly has been confirmed to travel 265 miles in one day. According to How Much Fuel Do Monarchs Burn? reporting Dr. David Gibo's research: On 140 milligrams of ...


32

The question headline seems to be slightly misinterpreting the company's claims Carefully rereading their claims, I realized they do not specify what Twisted Steel Micro Reinforcement (TSMR) reinforced concrete is better than. On a quick read, I just assumed they meant it is better than rebar reinforced concrete, because that is what the pictures imply, but ...


31

There was a similar question over on IT Security. I answer here as I answered there, based on my job experience in the alarm monitoring industry. The short answer is that the reverse-PIN system is documented as a possibility, but is not currently in use by any ATM network or manufacturer. The idea of the reverse PIN is the "duress code"; something that ...


30

And the mechanical friction caused by the alternator does not depend on whether electricity is being needed or not. Correct. In other words, when energy is not needed it is wasted Wrong. The electrical energy produced by the alternator is not the result of mechanical friction but of magnetic force on top of the (very small amount of) friction, which ...


29

The 'Dark Ages' (used here to describe approximately a thousand years following the fall of the Roman Empire) is a huge misnomer. It's often thought of as a time of stagnation between the Roman Empire and the Renaissance, but in actual fact it was a time of rapid technological progress. The later period was particularly rapid. From Wikipedia: During the ...


29

From TWO INTO ONE Shipbuilding and Shipping Record 28 June 1945: The U.S. destroyer escort Menges is back in service again. But only two thirds of her is the original ship; the other third was U.S.S. Holder another destroyer escort. Both ships were badly damaged in the Mediterranean, the Menges by two torpedoes, which killed 30 men and destroyed a large ...


28

Patents are bad for innovation and the economy, more often being a substitute for innovation than an incentive for it Free-market economists don't normally believe that monopolies are good for society - except where intellectual property (IP) is involved, where they argue that some temporary monopolies are worth permitting to provide an incentive for ...


28

The radiation is 1000 times stronger According to Wikipedia The transmission power of a GSM handset is limited to a maximum of 2 watts in GSM 850/900 and 1 watt in GSM 1800/1900. According to a Radio-Electronics.com article "GSM Power Control and Power Class" the base station controls handset power output in the range 2-19 which is 39 dBm to 5 dBm. ...


28

No. A typical home panel might consume the electricity released from about 1/2 a ton of coal. (Update: Or 1/6 a ton of coal, if you use combustion energy rather than electrical generation.) According to The Energy Balance of the Photovoltaic (PV) Industry: Is the PV industry a net electricity producer?, the Cumulative Energy Demand for photovoltaic cells ...


27

The image was taken 4 billion miles from Earth, according to NASA. The camera is a narrow-angle camera, with the following specifications: The Narrow-Angle camera optics is a 1500mm diameter focal length all-spherical, catadioptric cassegrain telescope (a modified MVM 1973 design) consisting of five elements plus an additional dust lens located ...


26

Yes. In addition to the 1960 Popular Science article you mention there was a 1923 Popular Science article: TAXI METERS USED IN ROME: Before the time of Julius Caesar, ancient Romans were called upon to travel in chariots for which they paid by a crude method of counting distances, according to a recently discovered records. The "taxicab" had a device ...


25

Nobody knows. None of the sources for total LOC provide any means or methods. Sources for hard numbers after 2008 were a little hard to come by, my apologies. Total number of lines of all code in use? One trillion (2001).[19] C/C++: 180 billion, Assembler: 140-220 billion, Other: 280 billion. Total number of lines of COBOL code in use? 200 billion (...


25

One study says, "possibly". Note that the illumination provided by the light sources used in the study may not be consistent with the light coming from a computer monitor. Also note that the sample size is not large, and a mechanism for the effect is not proposed. (source) J Physiol Anthropol Appl Human Sci. 2005 Mar;24(2):183-6. Effect of color ...


22

USB 1.x introduction Market share OS market shares of that time (Source): Windows 95/98 69.4%, Windows NT Workstation 9.2%, Windows 3.x (with DOS) 7.7%, Mac OS 4.6%, Linux 2.4%, DOS (IBM, Digital Research, Microsoft) 2.3%, Unix 1.0%, OS/2 Warp 0.8%, other 2.7% Windows 95 OSR2 released on 27 August 1997 included USB support and Windows 98 ...


22

The iMac was not only the first Mac to include USB, it was one of the first computers in general to have USB 1.1 ports. USB 1.1 fixed a lot of minor glitches with 1.0, and the rise of USB might very well be attributable to that instead. But the iMac may have helped, not so much by including USB ports, but by not including any legacy ports. That means that ...


21

How can we take an image of something that is less than 1 pixel ? Because telescopes (optical systems) record images of energy functions not objects. Telescopes, image sensors, and the human eye sense photons at various energy levels. If the photon is within the device's detectable frequency/energy range it will be recorded. The size of the object that ...


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