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Rail guns do not work that way! Good Night!

Back of the envelope time:

The cost to launch something to the ISS's orbit is something like $10,000/lb. Let's say they make it from typical 20-lb bonded paper - the kind you'd pull from a copier.A 500-sheet ream of 20-lb actually weighs about 5 lbs, or 1/100th of a pound per sheet. Do out the math, and it works out to about $100/sheet of paper.

Ouch! That's an expensive paper airplane!

Use a GAS as a deterent is NEVER going to fly. Have these people at the Pentagon completely forgotten about mustard gas and World War I? Secondly, the environmental repercussions. Thirdly, a gas mask can be used to avoid inhaling the gas. (Suck it, Riot Police!)

I think the best solution against stupid ideas for military weapons is for civilians to create protective equipment against it. I would really like to see someone invent the tazer-proof vest. If there is fire resistant equipment, bullet-proof vest, and buildings that can survive a bomb blast, then civilians need to develop technologies against tazers and energy weapons that use heat, sight, taste, smell, or sound against a growing threat of authoritarian government.

Yes, but we don't contract mad cow disease from the abnormal protein itself. The Prion theory is still just a theory. But the point is taken -- a genetic defect may well have some kind of communicability through simple digestion. Cloning is unlikely to be a factor in causing a heretofore unseen disease like BSE, and it is just as likely to occur in a population raised through normal biology.

Not a criticism of what you're saying, just an add-on:

In addition to different possibilities in resolution ( http://en.wikipedia.org/wiki/Digital_cinema#Digital_projection ), there's also the fact that for DLP-based system, individual, dedicated RGB projectors are used ( http://www.dlp.com/cinema/what.aspx ). This results in a superior viewing experience, not just because of the RGB breakout, but because the entire color system is superior. An abridged explanation is here - http://entertainment.howstuffworks.com/digital-cinema5.htm - if you're interested in some of the projection mechanics.

I just want them to grow me replacement teeth. The combination of poor oral care and weak enamel on my natural ones have messed me up pretty badly.
There's been some promising work done in the area. Eg. Growing teeth from stem cells and fabricating bones with a 3D printer.
But there's still so far to go :-(

US army detonated a few nukes at 350km alt, close to shuttle height, quite big ones and pretty. http://static.howstuffworks.com/gif/nuclear-test-9.jpg

Im sure this would have been noticed by someone given the burst of gamma rays etc...

I think you're confusing the solar furnace and the CR5. It says 88 square meter for the solar furnace. How many of the 45-pounds-per-day CR5 barrels can there be per solar furnace? Also, what portion of the waste heat from a coal-powered electric plant could be used to heat the barrels? Surely not all the heat goes into making steam for the turbines.

If one solar furnace could power 100 of the CR5s and there's enough CO2 to satisfy them, then you're talking about 250 gallons of fuel and 4500 pounds of CO2 that's being reused instead of just released. That's 946 liters and 2041 kilograms for the rest of the world, BTW. At a meager 20 miles per gallon, that would power the coal plant's maintenance fleet 5000 vehicle miles. A day. I think they might have some spare to sell to their employees at least.

If "large numbers" means 1000 per plant on average, then you're talking about each plant making 2500 gallons of fuel a day from 45,000 pounds of CO2. Given there are around 400 fossil-fuel power plants in the US, if you could get 2500 each per day, that's 1,000,000 per day. That's 365,000,000 gallons a year. At 42 gallons (159 liters) per barrel, that's 8,690,476 barrels of fuel. Remember that crude oil needs to be refined to become petrol, too. Only about 20 gallons per barrel of crude becomes gasoline. So figure it's about double, or 17 million barrels of oil not being imported (but that forgets the propane jet fuel, heating oil, etc made from the rest of the barrel) for use as gasoline.

Here's the catch with the previous paragraph: the US consumes about 20 million barrels a day, again about half as gasoline. So 1000 of these per power plant over a year would power the US auto fleet about 2 days.

But how much CO2 are we really talking here? There are two billion tons of CO2 released by coal-fired plants each year. If we could turn 90% of that (1.8 billion tons) into fuel at a rate of 45 pounds = 2.5 gallons then we're talking about 3,600,000,000,000 pounds and 200,000,000,000 gallons per year could be made. Two hundred billion gallons of gasoline. We use 10 million per day. That's 20,000 days worth of gasoline produced each year if we could find the room and perfect the technique of installing these things. That's over 50 years of gasoline at today's usage rates that we'd make each year.

If we really can make 50 years worth of gasoline or methanol each year from coal waste we're making anyway, why not? And that's just coal-fired plants in that last math. That's not including oil-powered ones or the blast furnaces at steel foundries, cement plants, and glass factories.

Also, note in TFA where it says water steam can be turned into elemental hydrogen using the exact same equipment. That sounds a bit cheaper and a lot cleaner than most current methods. Perhaps one solar furnace boils water out of the sea, and another powers the cobalt ferrite and oxygen reaction in a bunch of the CR5 reactor barrels. It's desalinization and hydrogen production from seawater without the input of electricity for hydrolysis.

I'm not a chemist, but I wonder these what devices would do with sulfur dioxide. The CR5 works by removing oxygen from the water or CO2, but does it work on SO2? If it does, will it produce Sx, SO, S2O or S202 at between 2000 and 2600 degrees C?

Yes, very true regarding the isolation. Additionally, planes' rigorous inspection and freedom from interference allows planes to be fly-by-wire, but we do not have this luxury with cars yet...

No production car has a total steer-by-wire system yet; every car still has an absolute mechanical linkage between the steering column and the wheels. A LOT of manufacturers have been looking into alternatives -- BMW in particular (I know this car manufacturer the best) has some completely "steer-by-wire" systems are in concept cars. They have a hybrid system currently called "active steer" since '04, which I think all BMWs have, which basically increases the angle to the wheels at lower speeds.

Numerous cars now have complete "throttle-by-wire", present in BMWs though since about 2004, so there is no mechanical gas pedal linkage, and this is now relatively common, but not universal among cars. Apparently there were some complaints about it early, but now the programming is very similar to the mechanical linkage. If you lose your throttle control due to a computer malfunction, it is simply not as bad as completely losing your steering.

For some really good articles on the issues involved, check out:

http://findarticles.com/p/articles/mi_hb078/is_200311/ai_hibm1G1110736640
http://www.autofieldguide.com/columns/1103pb.html

And some guy's Stanford Ph.D. thesis -- actually a pretty good read, summarizing issues nicely.
http://www-cdr.stanford.edu/dynamic/bywire/dissertation.pdf

http://auto.howstuffworks.com/steering5.htm

[citation needed]

I can't even find this claim on the internet, let alone evidence for or against it. There is mention that speedometers are often slightly off (here, for instance), but no claim that they're biased too low.

While I've never flown a helicopter (or any aircraft), aren't they able to remain fairly stationary, or does it require a great deal of effort?

Yes, keeping a helicopter stationary requires a lot of effort. Hovering is one of the first things that someone has to learn how to do when they learn to fly helicopters, and it's very, very, hard. Except in videogames, where flying helicopters is easy.

Result #8: Howstuffworks "How Women Work"

http://en.wikipedia.org/wiki/Fire-walking
http://people.howstuffworks.com/firewalking2.htm
http://www.indiasnews.com/details1/Aluminium

Bottom line: Aluminum is a fantastic conductor of heat which melts at 933k. Firewalking typically takes place on coals with a temperature of 1000k, using feet and coals that are both not good conductors of heat, and ash, which is a good insulator. Don't stand in place on hot coals, the heat transfer will make you regret it after a fairly short time.

For a 30 person external helpdesk department and our internal tech services teams. We've had a few minor niggles, but compared to what we were using before (Oaisys) it's cheaper and goes down less. For those who are interested, there's a brief precis of why call centre software is important here

Who even says that the sensor necessarily needs to be fully electronic? You can have a mechanical piece that sticks in the fuel tank and have an electronic control piece that's outside of the fuel tank. In fact, this is exactly how the gas gauge in your car works. This design has, quite frankly, worked well for decades. Sure there's a few disadvantages, but, uh, who cares?

Prove it.

you mean like:

Space Station
Space Shuttle

or

Las Vegas

or

Lincoln Financial Field

and... yeah, it is cool that the good old USA can muster up a few of these bad boys:

F-22

So I guess we're just totally broke?

Such risks are already well known:

I prefer the laser equivalent of this, stereolithography. It is faster and more precise.
Some fancy pictures.

Straight space as observed by human eyes and interpreted by human brains is defined by movement along a light ray path. It is obvious because if you are looking directly at an object as it appears that is where the photons come from.

Light bends severely near the event horizion making it an invisibility cloak even better than this one: http://science.howstuffworks.com/invisibility-cloak.htm because instead of mimicking the light it actually bends space to redirect the light itself. Sweet...

There is a point at which any object directly behind the black hole makes a ring due to space being bent like a lens so that the rays converge and fall on a single point. However lensing by a black hole, even up close, will resemble this http://www-ra.phys.utas.edu.au/~jlovell/simlens/lens_large.gif

I'd use the two bars shown to adjust the angle of the shaft to lean it forward or backward.

. . . diaper?

1-2 meter? where do you have those numbers from? Did ya just pull em out of your arse? IF things go so badly that the ice on Greenland and Antarctica melts, see level vill rice about 68 meters, 61 from Antarctica and 7 from Greenland.

http://science.howstuffworks.com/question473.htm
http://www.msnbc.msn.com/id/11385475/
http://news.bbc.co.uk/2/hi/science/nature/4720536.stm

Mind you, this is what you would have found had you bothered to ask google

I doubt any scientist will say the question is what happens to the sea lvl if the ice on Greenland and Antarctica melts, but rather IF it will melt and if the rice we now see in temperature is man made.

That's an old maid's tale. How Stuff Works has a decent article on sneezing. So does Snopes.

If "a kilogram of hydrogen is equivalent in energy to a gallon of gasoline" then, estimating about 400 million gallons of gas per day used by the US, we will need 10 million acres of algae farm. That is with the assumption that they obtain their optimal output, and no additional energy is expended for processing, transport, etc.

By contrast, an average nuclear power plant produces 1000 megawatts of energy. Also assuming optimum efficiency, we get (10^9 joules pers second * (60 * 60 *24) seconds per day / (237.1*10^3 joules to electrolyze 1 mole of hydrogen at 298K) * 1.01 grams/mole = 368,047 kilograms of hydrogen per day.

So... 10 nuclear plants, or 10 million acres of algae farm?

Let's not forget that your algae farm will stop photosynthesizing when it's cloudy out.

Even rolling forward slowly on an '82 Mercury Lynx I could not get mine to jam into reverse, and I tried with a fair amount of force.

"Reverse gear is handled by a small idler gear (purple). At all times, the blue reverse gear in this diagram is turning in a direction opposite to all of the other blue gears. Therefore, it would be impossible to throw the transmission into reverse while the car is moving forward -- the dog teeth would never engage. However, they will make a lot of noise!" -- Tranmission

I suspect if people get their cars to stall when jamming the shifter into reverse while rolling forward it's because they pop the clutch suddenly after hearing the grinding crunching noises.

If you mean BPL, it has been rolled out in a few rural areas of the US. I know Cinergy has a lot of BPL customers around Cincinatti.

I hoping it come to southern Indiana soon. Fast up and down.

http://money.howstuffworks.com/bank5.htm/ I know someone who started a bank 30 years ago with four partners and about $2,000,000 in assets. It's possible.

The company, which has three employees in Ireland, and two in a Santa Clara, Calif. office, has two other games, including Storm Chaser, where storms and wind howl until you relax, at which point, the sun comes out and birds start chirping, and Lie Detective, which gets more interesting because it detects whether youre lying or not.

Man, you got your analogy completely wrong.

GM = Car manufacturer = PC Manufacturer = Dell, HP, Lenovo, etc.
Microsoft = Operating System Manufacturer =?= Ignition System.

Therefore, according to your flawed analogy, there is no PC manufacturer making 90% of all computers... it is the Operating System the one which is holding a monopoly.

2935.041 Detention, arrest of shoplifters; protection of library, museum and archival institution property.

(A) A merchant, or his employee or agent, who has probable cause to believe that items offered for sale by a mercantile establishment have been unlawfully taken by a person, may, for the purposes set forth in division (C) of this section, detain the person in a reasonable manner for a reasonable length of time within the mercantile establishment or its immediate vicinity.

http://communication.howstuffworks.com/sms.htm

Your phone also uses the control channel for call setup. When someone tries to call you, the tower sends your phone a message over the control channel that tells your phone to play its ringtone. The tower also gives your phone a pair of voice channel frequencies to use for the call.

The control channel also provides the pathway for SMS messages. When a friend sends you an SMS message, the message flows through the SMSC, then to the tower, and the tower sends the message to your phone as a little packet of data on the control channel. In the same way, when you send a message, your phone sends it to the tower on the control channel and it goes from the tower to the SMSC and from there to its destination.

America has 9.6 million square kilometers of land. That converts to 960,000,000 hecatres. Jatropha produces 1,892 liters per hecatre. That means it would produce a theoretical 1,816,320,000,000 litres of fuel. 1.8 trillion litres of fuel. That's a little over 3x our current consumption rate, not about equal. Still not great though. I don't see biofuel being more than a niche supplier.

I know for a fact that at least one of DARPA Unmanned Ground Vehicles already has a hybrid power system. That beast can sneak up on you. Glad to see that tech also going into the manned vehicles.

" . . . (or better yet, a vinyl record)"

Oops, you were doing quite well up until then. Too bad that last bit lost you whatever credibility you might have started the post with.

Ummm... So did you. An explanation even with a picture for those of you that still don't understand why a fresh vinyl recording is better. I will give you the fact that old, worn vinyl will always suck - but a freshly pressed disc is the closest to pro quality that consumer gear ever got.

note: This very same point has been made countless times over the last 10 years on /.. You'd think by now we'd all know.

Face Recognition Vendor Test with actual tests and results.
http://frvt.org/

HowStuffWorks page on face recognition. See page 3 on Surface Texture Analysis to see how changes in face features do not break face recognition using that method. (ie, the distance between your eyes, shape of your eyes, skin texture on cheeks and forehead, etc. are all used to recognize a face.)
http://computer.howstuffworks.com/facial-recogniti on.htm

Brief introduction discussing 2D and 3D face biometrics. Notes how 3D imaging of faces defeats someone using a photo to fake the system.
http://www.3dface.org/home/introduction.html

MIT article talking about face recognition in detail (actually, discusses results of the FRVT 2006 test from first link).
http://www.technologyreview.com/printer_friendly_a rticle.aspx?id=18796

Also, some of these articles mention "liveness." This is a test where the camera takes multiple images, or is actually a video camera where every frame is analyzed (yes, you can analyze almost every frame in decent quality video for faces on a regular desktop PC). The algorithm looks for blinking eyes, slight movements in head position, etc, to ensure that the subject is "alive" and not a photo/fake.

Last note, the Surface Texture Analysis method can distinguish between identical twins. One company, Identix, has publicly tested this and challenged twins to present themselves to be identified. The system successfully identified each twin differently from the other. Even considering makeup, etc. (I can't find a good link for the test results, though there are several statements by Identix that their software ABIS 3.0 can distinguish between identical twins.)

Taken from Liquid Explosives article on how stuff works

most liquid explosives are made of unstable molecules. These complex molecules break down into ordinary, stable molecules when exposed to the right stimulus. Even a very minor shock can start the process, and since it involves the breaking of atomic bonds, it releases enormous amounts of energy.

The terrorists most likely intended to remove the explosives from their carry-on luggage and detonate them while the planes were over the Atlantic Ocean. They may have planned to use explosives that require the mixing of two different liquids in order to start the reaction. Unnamed sources have stated that the attackers planned to mix a liquid dyed to resemble a sports drink with a peroxide gel to create an explosive substance.

According to other sources, the attackers intended to use triacetone triperoxide, which can be made from readily available substances like hydrogen peroxide, acetone and acid. Like nitroglycerin, triacetone triperoxide molecules are made of hydrogen, oxygen and carbon. When it explodes, it breaks down into large amounts of ozone and acetone.

Haha- so this is the sort of article that I miss when I sleep? Anyway, I have collected some links that somebody might find useful to go start some more research. Maybe setup a basement lab or something.

-- General
* Irazoqui's neurotransceiver [pdf] [2003] The problem with Irazoqui's device is that it is maybe 1% power efficient, so maybe some electronicists can come around and make some suggestions to improve the coil design and so on. He did his testing on rats, not humans.
* Direct brain interface bibliography from the University of Michigan
* Gleamed from an article below: wireless visual cortex implant publications
-- EEG
* Controlling computers with EEG signals
* EEG via soundcard from OpenEEG
* Wireless EEG
-- Slashdot goodness
* Scientists couple nerve tissue with semiconductors
* Post re: neurosilicon junction with PDF
* Thinkware
* Good post w/ links on neurocomputation
* Brain slice experiments
* Neuroscientists at MIT doing direct neural interfaces- but this post sets things into perpsective as well as this one
* Single neuron recordings w/ ref
* Sorry to dash your hopes, but ...
* Autonomously adjusting electrodes? and more
* Artificial hippocampus and stimulating neuron growth / neurogenesis ... with Prozac?
* Implant a chip inside your head- though it does not discuss the specific surgery skills you would need
* Working nerve chip of silicon and snail neurons
* Re: Kevin Warwick- interview- the so-called "Captain Cyborg" since '98 or something
* BrainPort
* Fusing neurons with computers
-- More
* Artificial vision
* The vision quest
*

May the collective Slashdot mind forgive my anonymous cowardliness if I am wrong, but it is my understanding that ALL modern hard drives are of the IDE variety, Integrated Drive Electronics. That just means that the electronics are soldered to the drive along with the platters rather than a card or something else, correct? I see multiple people referring to IDE drives and IDE channels but http://electronics.howstuffworks.com/ide.htm/ also agrees that IDE is not the true name for the interface standard; just that since almost all IDE drives are of the Parallel ATA variety, the two terms are used interchangeably. Should the rapid onset of Serial ATA (rightly) make us change our terminology?

and propagate. http://science.howstuffworks.com/cloning1.htm

sugar in a gastank does crap all...
http://auto.howstuffworks.com/what-if-sugar-gas.ht m
A banana might block the exhaust, but most likely the starter is powerfull enough to create such an overpressure to send the banana flying.

This from ...

Wow, I think a lot of people totally missed it, so I'll try to help out. The sarcasm meters must be blown. Feel free to correct me if I'm wrong.

Worst-case scenario, wearing the suit brings your internal pressure to 2 atmospheres - something you can easily withstand in a (very thin) diving suit. Unless you spend a long time wearing the suit in full atmosphere, and the atmosphere hasn't been adjusted to not have gasses that increase your risk of the bends, you will soon be out in space and back to 1 atmosphere. You may not want to live in the suit full-time, but they don't do that right now. Why would you assume they would with this one?

If you'd read the article, you would have noticed that they said the target pressure is 30 kPa, about 1/3 atmosphere. That means wearing the suit full-time in the ship would put you at 1.3 atmospheres, which isn't huge. This site notes that 33 feet of water acts as 2 atmospheres, so we're talking like being under 10 feet of water on a long-term basis. Now, there's still the 1-atmosphere drop when you do an EVA, but this should be able to be handled with a decent decompression chamber (a.k.a. airlock), if it's even necessary.

To the original poster: commendations on a witty and relevant comment.

1) comms/antenna dome http://science.howstuffworks.com/predator1.htm
2) pusher prop planes can be more efficient (eliminate prop wash leads to less drag)
3) V-tail planes use two fins in place of three to reduce drag and weight. Can reduce radar signature in some instances. Original predator used this. But there must have been reason to flip them and add a third fin, keeping some semblance to the original (able to use existing parts and avionics?).
4) same reason camera/laser designators stick out on manned aircraft (including your local news chopper): wider field of view for the swiveling optics. Sometimes it's worth adding a bit of drag if you don't have to fly the aircraft all wonky just to see something.

drat, should have previewed before the previous post. Sorry.