Become a fan of Slashdot on Facebook


Forgot your password?

Comment Re:Nothing about the range (Score 1) 398

That tells me that there is a possibility to use this in hybrid engines. The compressed air could be used to give power for passing cars. The resulting cooling could be used to cool a main gasoline engine. In other cases it could be used in conjunction with electric engines because those have problems when high torque is needed. If compressed air could be when extra torque is needed, maybe this could reduce the need for rare earth magnets.


Submission + - Serious problems with USB and Ethernet on the Raspberry Pi (

rephlex writes: The USB controller used in the Broadcom BCM2835 (which is the SoC the Raspberry Pi uses) has buggy drivers which have been causing problems for many of its users. In addition to this the Pi can only supply an unusually low amount of current to its USB devices, just 140 mA approximately, and using a powered hub to sidestep this limit exacerbates the issues caused by the USB drivers. Even Ethernet is affected as the Ethernet controller used on the Raspberry Pi is connected to the SoC via USB. This has resulted in packet loss and even total loss of network connectivity in certain situations, see Attempts have been made in the past to fix the buggy USB drivers as there are other devices which use this problematic controller. None of these attempts seem to have achieved very much.

Submission + - NFS@Home Sets New Integer Factorization Record (

An anonymous reader writes: The 320-digit Mersenne number, 2^1061-1, has been factored by NFS@Home. The number factors into 143-digit and 177-digit prime numbers. This result sets a new record for the largest number factored by the Number Field Sieve. NFS@Home is powered by BOINC, and currently has over 1,000 volunteers contributing to the project.
The Military

Submission + - Air Force Claims to Solve Fatal F-22 Oxygen Riddle 1

Hugh Pickens writes writes: "DefenseTech reports that Air Force Maj. Gen. Charles Lyon, the director of operations for Air Combat Command, told the Pentagon press corps a valve that inflates the Combat Edge upper pressure garment is the cause of hypoxia-like symptoms in pilots flying the F-22 that forced the service to ground the Air Force’s most prized stealth fighter fleet for four months and led two Raptor pilots to tell the nation on CBS’s 60 Minutes that they refused to fly the jet because the pilots feared for their lives. The vests help control the breathing of pilots in high G-force environments inflating before pilots start to experience extreme G-force conditions. However Lyon explained that the valves caused the vests to inflate too early in an F-22 flight causing pilots to hyperventilate in the cockpits. “It’s like putting a corset around your chest,” said Lyons. Eagle and Viper pilots stopped wearing the upper pressure garments in 2004 “because they were not giving us the contribution we thought they would,” said Lyon. F-22 pilots kept wearing them because they flew at higher altitudes and the vests protected the pilots from “rapid decompression" adding that F-22 pilots, many of whom flew the F-15 and F-16, didn’t notice the vests had inflated early because of the layers of gear a pilot wears in flight. Such a simple answer to a problem that has eluded Air Force engineers and scientists for four years has left some Air Force pilots skeptical that the USAF has solved the problem with the fighter that been involved in seven major crashes with two deaths. An F-16 pilot said the Air Force is either “incompetent for missing this until now,” or “dishonest and trying to sweep something under the rug.”"

Comment Re:Why ignore inflation? (Score 1) 377

My feeling is that no true comparison can be made because the costs borne by the company making the mistake are only half the equation. The costs borne by stock holders or computer owners are ignored. By scaling the costs to inflation one gets a feeling that a more precise comparison is being made but it ignores the larger impact of the mistakes. There is no simple comparison to be made. It is all bragging rights.

Comment Re:Algorithms versus humans (Score 1) 377

On the one hand, algorithmic trading can screw up royally and cost hundreds of millions in a matter of hours. On the other hand, human traders can screw up royally and cost billions over a few months.

I'm not sure which is worse. And of course in combination they can crash national economies.

One difference is that a slow moving wreck caused by humans with human consequences is within our toolset of things that we can react to and in some cases mitigate or avoid. A wreck that destroys things when you blink is on the wrong timescale for prudent reactions.


Submission + - Can Anyone Catch Khan Academy? (

waderoush writes: "Even as name-brand universities like MIT and Harvard rush to put more courses on the Web, they're vying with an explosion of new online learning resources like Coursera, Udacity, Udemy, Dabble, Skillshare, and, of course, Khan Academy. With 3,200 videos on YouTube and 4 million unique visitors a month, Sal Khan's increasingly entertaining creation is the competitor that traditional universities need to beat if they want to have a role in inspiring the next generation of leaders and thinkers, this Xconomy commentary argues. Lately Khan's organization has been snapping up some of YouTube's most creative educational-video producers, including 'Doodling in Math Class' creator Vi Hart and Smarthistory founders Beth Harris and Steven Zucker. Universities are investing millions in software for 'massive online open courses' or MOOCs, but unless they can figure out how to make their material fun as well as instructive, Khan may have an insurmountable lead."

Slashdot Top Deals

Those who can't write, write manuals.