The probability of an impact anytime soon isn't any greater than it was, but other things have changed. Humanity has increased in numbers, put a lot of infrastructure on the planet and depleted a lot of the easily-available resources. Not only is there a lot more to be damaged, but the cost of replacing it is higher than it was. When you multiply the possible losses by that small probability, insurance looks better and better.
We don't know that we need to mount a mission yet, but someone could literally look in their telescope tonight and see a comet capable of causing a mass extinction event heading straight for us. It's only smart to have something that we can use, even if it's only a dual-use technology like a throwaway heavy-boost rocket that we can also use for Mars missions and stuff. What's the cost of developing something like that a little sooner and keeping something on hand? What's the cost of the network of telescopes required to find such threats, over and above the considerable scientific return that they'd yield? That's the beauty, most of the things you need to do to defend Earth against space hazards also promote other worthwhile goals.
Nice flamebait, period. My semi-rational response:
on
The Jobs Crunch
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· Score: 1
FDR tried to alleviate the suffering caused by the depression's very high unemployment rate by instituting SS, and work programs like CCC and WPA that provided a public benefit.
He also attempted to "solve" the problem of business failures by mandating higher prices, in the grossly mistaken idea that higher prices in isolation meant greater profits and thus more money to hire and pay employees. He completely forgot that higher prices meant that people had to have more money to buy the products, and a nation with 50% underemployment just did not have the prerequisites.
It's now claimed that FDR's "helping" prevented the Depression from ending in 1937 instead of 1943. I've read that Britain came out of it sooner than the US because of less interventionist policy. For this reason as well as many others, I consider FDR a self-serving nincompoop and his "New Deal" to be a huge and on-going problem.
If this country should be cursed with yet another George W. Bush term of office, do not expect that there will be any improvements in job growth,
health care, international relations, or the war in Iraq.
I've grown to expect idiotarian feel-goodism from both parties pandering to the nitwits who constitute their respective bases. I don't expect less from either; only the character changes a bit. If I could vote so that none of the current candidates won in November and they all had to go back and start over, I would consider it a good election. Instead, I am stuck with voting the rascal out as a lesson to the next rascal to try to be less idiotarian.
Assuming linear scaling, that means we're looking at upwards of 156 kilograms of HEU in this bomb.
Which is probably a bad way to project. In a pure-fission bomb, the chain reaction essentially stops when the expansion has made the core go back below a prompt-supercritical configuration. In a thermonuclear device, the fusion core emits gram quantities of 14.7 MeV neutrons which are sufficient to fission large parts of even a U-238 case; they ought to cause the fission of a U-235 tamper to go a large way to completion, so the fission yield per unit of HEU is probably a lot higher than you'd get from a normal fission bomb.
I actually like the idea of having a few "missing bombs" and whatnot out there, though. They are not all that difficult to watch, and if terrorists first expend a lot of effort on plans to retrieve them and then get caught in the implementation we keep them away from things that can do real damage.
H2 from sunflower oil. Okay, sounds great. But tell me, how much sunflower oil would it take to power the nation (or any reasonable fraction thereof, such as the transport sector) using this invention?
You don't know? Didn't even stop to ask?
I didn't think so.
Being a wet blanket bugs me sometimes, but somebody has to do the dirty work of dragging everything back down to earth and facing facts. Here are some:
The reactor doesn't generate hydrogen with 90% efficiency, it generates hydrogen of 90% purity. Given that the off-gas is about half methane (RTFA) it appears to me to be very inefficient. (Note: neither the author nor your Slashdot editor bothered to RTFA either.)
There are already engines, and even fuel cells, which can burn hydrocarbons directly. Sunflower oil makes reasonable diesel fuel as-is. Solid-oxide or molten-carbonate fuel cells can reform fuels internally, and while they might coke up on straight sunflower oil they'd probably work just fine after it had been steam-reformed a bit.
Hydrogen as a motor fuel suffers from huge problems with storage. People see it as sexy but for all the wrong reasons.
I could see this as another technology for making compact laptop power supplies whose fuel couldn't be used to bring down an airplane (just TRY making a fuel-air bomb with sunflower oil). The key to renewable energy? Gimme a break.
Tritium is an emitter of low-energy beta particles which are easily stopped. If the glass envelopes didn't halt the radiation, the plastic housing would. You could ship those things over borders 3 times a day and you wouldn't catch them without using very special instrumentation.
I am told that the radiation from tritium penetrates so poorly that standard detectors cannot read it; nothing gets through the detector housing. But you probably don't have to worry about exposure even if you do break it; hydrogen gas doesn't hang around very long, and isn't absorbed very much by building materials. You'll probably get more radiation from the concrete.
Somewhat counter-intuitively, gradual acceleration is not the ideal fuel economy move. According to a BMW study, accelerating smartly gets you into a higher, more economical gear more quickly and reduces the engine's pumping losses due to partial throttle.
This is only true if you aren't increasing losses elsewhere. If you are using an automatic transmission, faster acceleration means greater slippage in the torque converter and lower overall efficiency. Only when you get to the point where the lockup clutch activates (or if you can force it on) do you have anything close to equivalence between autos and manuals.
This is due to design decisions on the part of the auto makers: the hydraulic torque converter is a huge energy sink. If they used CVTs or a hybrid with a generator between the engine and transmission input shaft (turning the RPM difference of the slippage into electricity instead of converting it to heat) the difference would be a lot smaller, perhaps even negative.
If you, like me, prefer to buy a car made in the good ol' USA... the light truck platform is currently the only way to get a vehicle that will actually go 100,000 miles.
I've got a 1994 Ford 4-door with 170,000 miles on it. Should have as many miles left in it if you drive it the way I did. 0-60 in about 8.
It's for sale. It can barely reach 30 MPG at a slow 60 MPH cruise, and I've got a new car that will do nearly 50 MPG under the same conditions and is otherwise equivalent.
Mom could be going to pick up the soccer team, Dad could be going to Lowes for a new bathroom vanity or it could simply be that once the owner bought a $45,000 truck he/she couldn't afford the electric bicycle that would make YOU happy.
How much would Dad save by having Lowe's do the delivery, or renting the box truck from Home Despot for an hour? I bet he could rent a load's worth of truck every week for the extra payment he's making for that SUV, and just pocket the savings in fuel.
Mom had a choice between the electric bicycle and the flip-down DVD option. She picked the one that leaves her fatter, less fit and with a lower life expectancy, and her country in worse shape in several different ways. She deserves all the disgust being levelled at her.
What the USA needs is $5/gallon gasoline. We're already paying that much, but the extra $3 or so is coming from income taxes for defense and the like. Let's put those costs on the actvities which create them and see if America doesn't get smarter about things.
I've got a 5-passenger 4-door sedan (diesel), and I'm averaging better than 35 MPG even in local commuting (major roads, little stop-and-go though). I am burning about half the fuel of the 4x4 trucks and less than 1/4 as much as all the jerks running around in their H2 Hummers.
Things could be better. Cruising at 55 MPH, the dash readout claims instantaneous mileage of 50+ MPG. If the car was a hybrid it would recover a lot of the losses in city driving and probably beat 40 MPG for that too. That would cut about 1/3 off the fuel consumption of a vehicle getting the EPA average (more in actuality, because the city consumption of a conventional car would be considerably higher).
We can make a huge difference. What we lack is the broad cultural knowledge that we can (too many people deny the facts), and the will to do it.
You've fallen for intentional deceit. I quote your link:
If we raise fuel efficiency standards in American cars by one mile per gallon, in one year, we would save twice the amount of oil that could be obtained from the arctic national wildlife refuge
Raise it by 2.7 miles a gallon to eliminate all the oil imports from Iraq and Kuwait combined
Raise it by 7.6 mpg, we eliminate one-hundred percent of our gulf oil imports into this country
Only one of these three claims is actually meaningful. Dissecting:
True and relevant. The USA's import situation is directly affected by the difference between production and consumption; reducing consumption cuts imports just as directly as increased production does.
Perhaps true, but irrelevant. Oil is fungible, and while Persian Gulf oil goes primarily to Europe and the Far East it would be simple to re-route the tankers so that all of US imports came from there... or none of them. This would have no effect on US import dependence, the political implications of e.g. Wahhabi financing of hate teaching, or anything else of importance.
Perhaps true, but equally irrelevant for the reasons stated above.
Roughly half of all US oil consumption goes for motor gasoline, while over half of all US oil consumption is from imports. You could make every passenger car in the USA run on electricity and you would still not eliminate oil imports (though you'd probably collapse the world market for oil for a while and bankrupt a kingdom or three).
He won't take away all the computers in the world. He'll just take away the computer of anyone doing anything that the Powers That Be don't like; the statute will be broad enough to effectively prohibit all computer use, but it will be selectively enforced.
The chilling effect from discriminatory enforcement of the overbroad law is what makes it so wrong and so corrupting to the rule of law. "The more corrupt the state, the more numerous the laws." -- Tacitus
I know of a guy who weighed 350+ and had it done. Magically the weight started dropping dramatically with no other changes (that I'm aware of).
Eating smaller portions more frequently is supposed to be good for weight loss even with the same calorie intake. Stomach stapling reduces the stomach volume and thus the amount which can be eaten at a sitting. This would enforce the many-small-meals style but at a much greater cost and risk; it would behoove one to try doing it "on the honor system" to see if it works.
That's the problem with words like tenacity: they can't be understood by reference to English words of one syllable, so a large fraction of the American public will not understand them.
Try using "pecuniary" to the average college student. Or even "glutton". I once found someone working in a restaurant who did not know what "glutton" meant.
I could drop a lit match into the fuel tank of my diesel car and it would just go out.
And the truth is, it has a good chance of not going out, and blowing burning fuel all over the place. This is bound to ruin somebody's whole day.
The point you are missing is that gasoline vapor forms an incombustible mixture (too rich) inside tanks at most temperatures we're interested in. You can ignite vapor spilling from the tank, but it cannot flash back into the tank and burning material put into the tank will just go out.
Gasoline vapors in an enclosed tank will quench a match because they are too rich to burn. This is not true of petroleum diesel; the combustible range of saturated diesel vapors overlaps with our comfort zone. Biodiesel is another matter; it has a flash point greater than 300 degrees F, and if your car's fuel tank gets that hot you have bigger problems.
It would take some motor to give you ignition there; the motor in a phone vibrator is very small, fully enclosed, and the surfaces are much closer together than the "quench distance" for a gasoline flame. In order to get a flame out, the flame has to find combustible mixture faster than it loses heat via conduction or radiation. All you need to stop a flame is a metal screen, which is how the Davies lamp stops ignition of methane gas.
You're not going to get high voltage out of a piezo transducer which is being driven from a 4.5 volt battery through a low-impedance path. And if you could get high voltage by dropping it, lots of people would have blown electronics from dropping their phones; you might notice that this does not happen.
One wonders if static between e.g. a skirt and nylon stockings could provide a spark sufficient for ignition. If so, it would mean fewer skirts being worn which would be a serious loss for masculinity.
The advantage is...
on
Metal Velcro
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· Score: 4, Insightful
that the attachment of e.g. fibers in a composite to the metal protrusions does not depend on the bonding mechanism of a glue. The glue may age and fail, but the mechanical entanglement will not.
If I understand you correctly, you are talking about feeding cattle in pastures, at what, a few animals to the acre? Your density is a small fraction of what you find in a feedlot, where the animals are fed mostly grain rather than hay.
(And the word is "bales", not "bails" [which is a verb].)
Dairy cows tend to shit in a barn while they're being milked. This creates a lot of waste in a small area, that we typically just hoss out the back.
I was under the impression that feedlots where beef cattle are fattened tend to generate a lot of manure in a small space also. Maybe not quite as conveniently lined up as your rows of milk cows, but anything that you have to scrape up and put someplace could just as easily be put into a slurry-former and fed to a digester, no?
On the other hand, there is something that stinks a little when you over and over and over get to hear people from USA state that the "real" problem is the inefficient industries in China, while at the same time having the highest CO2-pro-capita of the entire world, 9 times that of China, for example.
Note that those figures prove that the USA produces 2.2 times the GNP per unit of CO2 than China does. So exactly what is the problem as you see it:
That some people in the USA refuse to allow a double standard and actually hold others to blame for their contributions to the problem, or
That the USA's standard of living is so much higher than e.g. China's?
I see a lot of USA-bashing in the world press, and enormous hypocrisy on the the part of many people and nations doing it. I'm not about to give anyone carte blanche.
Slashdot Mirror
We don't know that we need to mount a mission yet, but someone could literally look in their telescope tonight and see a comet capable of causing a mass extinction event heading straight for us. It's only smart to have something that we can use, even if it's only a dual-use technology like a throwaway heavy-boost rocket that we can also use for Mars missions and stuff. What's the cost of developing something like that a little sooner and keeping something on hand? What's the cost of the network of telescopes required to find such threats, over and above the considerable scientific return that they'd yield? That's the beauty, most of the things you need to do to defend Earth against space hazards also promote other worthwhile goals.
It's now claimed that FDR's "helping" prevented the Depression from ending in 1937 instead of 1943. I've read that Britain came out of it sooner than the US because of less interventionist policy. For this reason as well as many others, I consider FDR a self-serving nincompoop and his "New Deal" to be a huge and on-going problem.
I've grown to expect idiotarian feel-goodism from both parties pandering to the nitwits who constitute their respective bases. I don't expect less from either; only the character changes a bit. If I could vote so that none of the current candidates won in November and they all had to go back and start over, I would consider it a good election. Instead, I am stuck with voting the rascal out as a lesson to the next rascal to try to be less idiotarian.I actually like the idea of having a few "missing bombs" and whatnot out there, though. They are not all that difficult to watch, and if terrorists first expend a lot of effort on plans to retrieve them and then get caught in the implementation we keep them away from things that can do real damage.
You don't know? Didn't even stop to ask?
I didn't think so.
Being a wet blanket bugs me sometimes, but somebody has to do the dirty work of dragging everything back down to earth and facing facts. Here are some:
- The reactor doesn't generate hydrogen with 90% efficiency, it generates hydrogen of 90% purity. Given that the off-gas is about half methane (RTFA) it appears to me to be very inefficient. (Note: neither the author nor your Slashdot editor bothered to RTFA either.)
- There are already engines, and even fuel cells, which can burn hydrocarbons directly. Sunflower oil makes reasonable diesel fuel as-is. Solid-oxide or molten-carbonate fuel cells can reform fuels internally, and while they might coke up on straight sunflower oil they'd probably work just fine after it had been steam-reformed a bit.
- Hydrogen as a motor fuel suffers from huge problems with storage. People see it as sexy but for all the wrong reasons.
I could see this as another technology for making compact laptop power supplies whose fuel couldn't be used to bring down an airplane (just TRY making a fuel-air bomb with sunflower oil). The key to renewable energy? Gimme a break.I am told that the radiation from tritium penetrates so poorly that standard detectors cannot read it; nothing gets through the detector housing. But you probably don't have to worry about exposure even if you do break it; hydrogen gas doesn't hang around very long, and isn't absorbed very much by building materials. You'll probably get more radiation from the concrete.
Otherwise, good restatement of "oil is fungible". It is amazing how many so-called geeks are ignorant of such basic economic facts.
This is due to design decisions on the part of the auto makers: the hydraulic torque converter is a huge energy sink. If they used CVTs or a hybrid with a generator between the engine and transmission input shaft (turning the RPM difference of the slippage into electricity instead of converting it to heat) the difference would be a lot smaller, perhaps even negative.
It's for sale. It can barely reach 30 MPG at a slow 60 MPH cruise, and I've got a new car that will do nearly 50 MPG under the same conditions and is otherwise equivalent.
How much would Dad save by having Lowe's do the delivery, or renting the box truck from Home Despot for an hour? I bet he could rent a load's worth of truck every week for the extra payment he's making for that SUV, and just pocket the savings in fuel.Mom had a choice between the electric bicycle and the flip-down DVD option. She picked the one that leaves her fatter, less fit and with a lower life expectancy, and her country in worse shape in several different ways. She deserves all the disgust being levelled at her.
What the USA needs is $5/gallon gasoline. We're already paying that much, but the extra $3 or so is coming from income taxes for defense and the like. Let's put those costs on the actvities which create them and see if America doesn't get smarter about things.
Things could be better. Cruising at 55 MPH, the dash readout claims instantaneous mileage of 50+ MPG. If the car was a hybrid it would recover a lot of the losses in city driving and probably beat 40 MPG for that too. That would cut about 1/3 off the fuel consumption of a vehicle getting the EPA average (more in actuality, because the city consumption of a conventional car would be considerably higher).
We can make a huge difference. What we lack is the broad cultural knowledge that we can (too many people deny the facts), and the will to do it.
- True and relevant. The USA's import situation is directly affected by the difference between production and consumption; reducing consumption cuts imports just as directly as increased production does.
- Perhaps true, but irrelevant. Oil is fungible, and while Persian Gulf oil goes primarily to Europe and the Far East it would be simple to re-route the tankers so that all of US imports came from there... or none of them. This would have no effect on US import dependence, the political implications of e.g. Wahhabi financing of hate teaching, or anything else of importance.
- Perhaps true, but equally irrelevant for the reasons stated above.
Roughly half of all US oil consumption goes for motor gasoline, while over half of all US oil consumption is from imports. You could make every passenger car in the USA run on electricity and you would still not eliminate oil imports (though you'd probably collapse the world market for oil for a while and bankrupt a kingdom or three).The chilling effect from discriminatory enforcement of the overbroad law is what makes it so wrong and so corrupting to the rule of law. "The more corrupt the state, the more numerous the laws." -- Tacitus
You mean we'll never be certain that we caught you. Or that you're alive. Depends how close you were to Schroedinger's cat...
Try using "pecuniary" to the average college student. Or even "glutton". I once found someone working in a restaurant who did not know what "glutton" meant.
The point you are missing is that gasoline vapor forms an incombustible mixture (too rich) inside tanks at most temperatures we're interested in. You can ignite vapor spilling from the tank, but it cannot flash back into the tank and burning material put into the tank will just go out.
Gasoline vapors in an enclosed tank will quench a match because they are too rich to burn. This is not true of petroleum diesel; the combustible range of saturated diesel vapors overlaps with our comfort zone. Biodiesel is another matter; it has a flash point greater than 300 degrees F, and if your car's fuel tank gets that hot you have bigger problems.
It would take some motor to give you ignition there; the motor in a phone vibrator is very small, fully enclosed, and the surfaces are much closer together than the "quench distance" for a gasoline flame. In order to get a flame out, the flame has to find combustible mixture faster than it loses heat via conduction or radiation. All you need to stop a flame is a metal screen, which is how the Davies lamp stops ignition of methane gas.
You're not going to get high voltage out of a piezo transducer which is being driven from a 4.5 volt battery through a low-impedance path. And if you could get high voltage by dropping it, lots of people would have blown electronics from dropping their phones; you might notice that this does not happen.
Maybe fire prevention is tied more to getting people to pay attention to pumping the gas (and not spilling any) than phones or otherwise.
One wonders if static between e.g. a skirt and nylon stockings could provide a spark sufficient for ignition. If so, it would mean fewer skirts being worn which would be a serious loss for masculinity.
that the attachment of e.g. fibers in a composite to the metal protrusions does not depend on the bonding mechanism of a glue. The glue may age and fail, but the mechanical entanglement will not.
(And the word is "bales", not "bails" [which is a verb].)
- That some people in the USA refuse to allow a double standard and actually hold others to blame for their contributions to the problem, or
- That the USA's standard of living is so much higher than e.g. China's?
I see a lot of USA-bashing in the world press, and enormous hypocrisy on the the part of many people and nations doing it. I'm not about to give anyone carte blanche.