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Comment Re:Iron Man's Suit Defies Physics -- Mostly (Score 2, Interesting) 279

by John Carmack (#23266718) Attached to: The Science of Iron Man
Hydrogen peroxide powered rocket packs fly for around 30 seconds, because they have a specific impulse of around 125, meaning that one pound of propellant can make 125 pound-seconds of thrust, meaning that it takes about two pounds of propellant for every second you are in the air. Mass ratios are low for anything strapped to a human, so the exponential nature of the rocket equation can be safely ignored.

A pretty hot (both literally and figuratively) bipropellant rocket could manage about twice the specific impulse, and you could carry somewhat heavier tanks, but two minutes of flight on a rocket pack is probably about the upper limit with conventional propellants.

However, an actual jet pack that used atmospheric oxygen could have an Isp ten times higher, allowing theoretical flights of fifteen minutes or so. Here, it really is a matter of technical development, since jet engines have thrust to weight ratios too low to make it practical. There is movement on this technical front, but it will still take a while.

John Carmack
Microsoft

Microsoft Says Free Software Violates 235 Patents 1217

Posted by Zonk from the rut-roh-raggy dept.
prostoalex writes "Microsoft told Fortune magazine that various free software products violate at least 235 patents, and it's time to expect users of this software to pay up patent licensing royalties: 'Microsoft General Counsel Brad Smith and licensing chief Horacio Gutierrez sat down with Fortune recently to map out their strategy for getting FOSS users to pay royalties. Revealing the precise figure for the first time, they state that FOSS infringes on no fewer than 235 Microsoft patents.'"
The Almighty Buck

Long Range Eye Tracking for Advertisers 134

Posted by samzenpus from the The-unseen-mechanized-eye dept.
holy_calamity writes "A Canadian firm has launched a device that can track the gaze of multiple people from up to 10 metres away. Originally developed at Queen's University, Ontario, they hope to sell it to advertisers to allow them to monitor how many people look at their ads. Admittedly they are trying more benign stuff too like better hearing aids, but I doubt that will make up for movie posters that make a song and dance whenever you glance their way."
Windows

Vista Eating Battery Life 379

Posted by CowboyNeal from the glutton-for-power dept.
LWATCDR writes "It looks like more issues with Vista drains notebook batteries. Using the Aero interface really eats into your notebooks battery life. Of course one of the new 'features' of Vista is supposed to be better power management. This provides a great opportunity for a showdown. How long until someone loads Vista on a MacBook and compares run time? It would provide a flat playing field now that Apple makes Intel-powered notebooks."
The Internet

Is Virtual Rape a Crime? 690

Posted by ScuttleMonkey from the because-/quit-is-so-hard-to-type dept.
cyberianpan writes "Wired is carrying commentary on the story that Brussels police have begun an investigation into a citizen's allegations of rape in Second Life. For reasons of civil liberty & clarity we'd like to confine criminal law to physical offenses rather than thought crimes but already threats, menace & conspiracy count as crimes. Could we see a situation where our laws extend?"

Why Apple Should Acquire AMD 340

Posted by CmdrTaco from the what-else-do-you-do-with-mad-ipod-money dept.
slashdotLIKES writes "CoolTechZone.com columnist Gundeep Hora has a new column up that discusses why Apple should acquire AMD and how both companies would be a good fit for each other. From the article, "After private equity groups, let's look at a more strategic acquisition. For that, Apple is the best bet. Yes, I know it sounds way too radical to be taken seriously. However, Apple could drop Intel altogether and adopt AMD for its Macintosh PCs. Sure, the transition is going to take sometime, and it would probably make Apple announce a brand new line of PCs. However, it will be well worth it. We know Steve Jobs is ruthless when it comes to making interesting deals with powerful companies. This makes AMD a perfect match. Obviously Intel isn't going to be too delighted, but other companies don't bother Jobs. We all know he's the type of executive who crafts deals on his own terms. If Intel wants to be associated with Apple, then they won't really have much of a choice."
Apple

Hi, I'm a Mac, and I'm Your Enterprise Computer 469

Posted by Zonk from the hey-there-mac dept.
Esther Schindler writes "Not just another 'why big companies should adopt Macs' article, CIO is running a piece assuming that Macs are already on the way in the door. Hi, I'm a Mac, and I'm Your Enterprise Computer offers advice to IT managers about how to integrate Apple systems into the existing IT infrastructure, and offers hints from leading Mac OS X experts on configuring those systems once they've arrived. '[A] key element in corporate Macintosh adoption is the importance of third-party software and custom solutions. They can help smooth the way for integrating Macs onto the network. While specialists say they wish third-party support were greater, the openness of the Mac makes correcting issues possible. Don't discount the lure of the well-worn path that draws and then traps your IT staff into familiar habits.'"
Space

The Hundred Million Mile Pipe Organ 76

Posted by kdawson from the louder-than-yours dept.
jd writes "Scientists have announced that the gigantic coils of plasma in the solar atmosphere, known as coronal loops, actually carry sound waves much like a pipe organ. Micro-flares on the surface of the sun create powerful blasts of charged particles, which are then guided through the coronal loops, creating the standing waves. Sheffield University is hosting movies and audio recordings of the sun's performance."
Education

Many Dead In Virginia Tech Shooting 2661

Posted by CmdrTaco from the funny-not-appropriate dept.
nexuspal writes "Over 20 confirmed dead at Virginia Tech. Shooter killed some at residence hall then two hours later killed others in classrooms. Worst school shooting in US history. "
Encryption

AACS Cracked Again 306

Posted by kdawson from the persistence dept.
EmTeedee sends us to a blog post for a summary of the latest results in cracking AACS, from the Doom9 forums (as the earlier cracks have been) — after the DVD Security Group said it had patched the previous flaws. From the DLTV blog: "This time the target was the Xbox 360 HD DVD add on. Geremia on Doom9 forums has started a thread on how he has obtained the Volume ID without AACS authentication. With the aid of others like Arnezami they have managed to patch the Xbox 360 HD DVD add on... It appears that XT5 has released [an] application that allows the Volume ID to be read without the need to rewrite the firmware. This would mean that anyone could simply plug in the HD DVD drive and obtain the Volume ID from any HD DVD without the hassle of flashing it."
Movies

Computer Interaction in Science Fiction Movies 232

Posted by Zonk from the there-is-no-spoon dept.
MidVicious writes "From futuristic 'Punch Cards' to Voice Recognition HoloDeck Interfaces, human/computer interactions have always mirrored the base concepts of our emerging technologies. An article from a Saarland University CS Seminar highlights Hollywood history with UI, ranging from the moderately feasible (Total Recall's television/scenery display wall) to the often ridiculous (Swordfish's 6-flat screen monitor setup complete with 3-D virus-hacking environment). An interesting read, especially considering some of the technology is on its way to becoming a reality."
Operating Systems

How Long Does it Take You to Tweak a New Box? 463

Posted by Cliff from the a-never-ending-process dept.
An anonymous reader asks: "When you get a new computer, how long does it take to make it 'home'? On a Windows system, there seem to be a huge number of preferences I have to choose before it is really comfortable (doing things like: installing software; changing the wallpaper and color schemes; start menu layout; and so forth). How long do you have to fiddle with computer until you have it set up the way you like? Do you use any shortcuts to speed up the process?"
Windows

HardOCP Spends 30 Days With Vista 662

Posted by ScuttleMonkey from the second-verse-same-as-the-first dept.
boyko.at.netqos writes "Hardocp.com has published "30 days with Vista" — with the same author from "30 days with Linux" doing the evaluation. And he doesn't like it. From the article: 'Based on my personal experiences with Vista over a 30 day period, I found it to be a dangerously unstable operating system, which has caused me to lose data [...] Any consideration of the fine details comes in second to that one inescapable conclusion. This is an unstable operating system.'"
United States

Daylight Saving Change Saved No Power 766

Posted by kdawson from the pay-me-now-or-pay-me-later dept.
Brett writes "Results from energy companies are coming in, and the word is that moving Daylight Saving Time forward three weeks had no measurable impact on power consumption. The attempt by the US Congress to make it look like they were doing something about the energy crisis has been exposed as the waste it is. But the new DST is probably here to stay — letting the bill expire would mean re-patching a lot of systems again next year. So much for saving energy."
Input Devices

Hacking Our Five Senses 232

Posted by Zonk from the still-waiting-for-a-eyeball-based-hud-thanks dept.
zdude255 writes "Wired is running an article exploring several studies of giving the human brain 'new input devices.' From seeing with your sense of touch to entirely new senses such as sensing direction intuitively, the human brain seems to be capable of interpreting and using new data on the fly. This offers many applications from pilots being able to sense the plane's orientation to the potential recovery of patients with blindness or ear damage. (which helps balance).'It turns out that the tricky bit isn't the sensing. The world is full of gadgets that detect things humans cannot. The hard part is processing the input. Neuroscientists don't know enough about how the brain interprets data. The science of plugging things directly into the brain -- artificial retinas or cochlear implants -- remains primitive. So here's the solution: Figure out how to change the sensory data you want -- the electromagnetic fields, the ultrasound, the infrared -- into something that the human brain is already wired to accept, like touch or sight.'"

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