Slashdot is powered by your submissions, so send in your scoop


Forgot your password?
Check out the new SourceForge HTML5 internet speed test! No Flash necessary and runs on all devices. ×
Hardware Hacking

Home-Built Turing Machine 123

stronghawk writes "The creator of the Nickel-O-Matic is back at it and has now built a Turing Machine from a Parallax Propeller chip-based controller, motors, a dry-erase marker and a non-infinite supply of shiny 35mm leader film. From his FAQ: 'While thinking about Turing machines I found that no one had ever actually built one, at least not one that looked like Turing's original concept (if someone does know of one, please let me know). There have been a few other physical Turing machines like the Logo of Doom, but none were immediately recognizable as Turing machines. As I am always looking for a new challenge, I set out to build what you see here.'"

Submission + - Facebook Awarded Patent for its News Feed

adeelarshad82 writes: Facebook has secured a patent to a feature that many of its competitors have adopted in recent years, the news feed. The patent, officially granted on Tuesday by the U.S. Patent and Trademark Office, governs a "method for displaying a news feed in a social network environment." Facebook applied for the patent back in August 2006, about a month before the social networking site opened its doors beyond college students to all Internet users.
Data Storage

Submission + - Exploring Advanced Format Hard Drive Technology ( 1

MojoKid writes: Hard drive capacities are sometimes broken down by the number of platters and the size of each. The first 1TB drives, for example, used five 200GB platters; current-generation 1TB drives use two 500GB platters. These values, however, only refer to the accessible storage capacity, not the total size of the platter itself. Invisible to the end-user, additional capacity is used to store positional information and for ECC. The latest Advanced Format hard drive technology changes a hard drive's sector size from 512 bytes to 4096K. This allows the ECC data to be stored more efficiently. Advanced Format drives emulate a 512 byte sector size, to keep backwards compatibility intact, by mapping eight logical 512 byte sectors to a single physical sector. Unfortunately, this creates a problem for Windows XP users. The good news is, Western Digital has already solved the problem and this quick overview at HotHardware offers some insight into the technology and how it performs.

Submission + - HTML5 vs Flash (

An anonymous reader writes: Here's an article that provides a lowdown on whether HTML5 is going to smackdown Flash when it comes to mobile apps or whether the standard will be obsolete by the time that its specifications are finally ratified.

Open Textbooks Win Over Publishers In CA 216

Unequivocal writes "Recently California's Governor announced a free digital textbook competition. The results of that competition were announced today. Many traditional publishers submitted textbooks in this digital textbook competition in CA as well as open publishers. An upstart nonprofit organization named CK-12 contributed a number of textbooks (all free and open source material). 'Of the 16 free digital textbooks for high school math and science reviewed, ten meet at least 90 percent of California's standards. Four meet 100 percent of standards.' Three of those recognized as 100% aligned to California standards were from CK-12 and one from H. Jerome Keisler. None of the publisher's submissions were so recognized. CK-12 has a very small staff, so this is a great proof of the power of open textbooks and open educational resources."

New Type of Particle May Have Been Found 281

An anonymous reader writes "The LHC is out of commission, but the Tevatron collider at Fermilab is still chugging along, and may have just discovered a new type of particle that would signal new physics. New Scientist reports that the Tevatron's CDF detector has found muons that seem to have been created outside of the beam pipe that confines the protons and anti-protons being smashed together. The standard model can't explain the muons, and some speculate that 'an unknown particle with a lifetime of about 20 picoseconds was produced in the collision, traveled about 1 centimeter, through the side of the beam pipe, and then decayed into muons.' The hypothetical particle even seems to have the right mass to account for one theory of dark matter."

Black Holes May Not Grow Beyond Certain Limit 201

xyz writes "Do black holes increase in size indefinitely? According to an analysis by astronomers at Yale and the European Southern Observatory, the maximum size a black hole may reach is only few tens of billion of solar masses. The limit was calculated using an analysis of what may happen to the gas surrounding a black hole which has reached few tens of billions of solar masses. It is thought that black holes of such size heat the surrounding gas to a temperature where the radiation pressure begins blowing outer layers into space."

Slashdot Top Deals

If I were a grave-digger or even a hangman, there are some people I could work for with a great deal of enjoyment. -- Douglas Jerrold