There *IS* a pretty decent benchmark out there which actually correlates well with processing power in terms of data processing speed.
It was called the HINT benchmark and it was developed by a guy at Iowa State University Ames Laboratory. I think they tried to commercialize it but it didn't get off the ground. It was released under the GPL. It's out there in various places.
If you can find a copy of the software then compile it up, and it produces some very interesting data. It produces a curve of "quality improvements per second" as a function of memory usage...
So that the people who were duped don't realize that they were duped by real bad guys, instead they think it was a security audit by good guys, so they take no action.
You should do an economic analysis of the cost of getting a rugged camera vs the cost of simply replacing the cheaper consumer level ones every 9 months or so. Also, consider buying a replacement warranty from some place like Best Buy.
It's got to be cheaper to simply replace the Sony every 9 months using the Best Buy warranty than it is to buy one of those pro dvcams. A typical pro level camera is around $5k and up, so you have to get 10 years of use out of the pro one to make it worthwhile at 0% interest rate. At real interest rates it's even longer life required. Do you really even WANT 10 years of service from a camera? Tech changes faster than that.
Rule based programming's purpose is to solve a problem that requires complicated logic by declaring what the relationships are, instead of describing a procedure that solves the problem.
The advantage in these sorts of uses is that you can reason about the declarative program much easier than you can about the set of steps that you would write down in a procedural language.
SQL is a kind of declarative language that you might be familiar with. Although it is much less powerful than say prolog, its advantages for searching for information over something like a bunch of perl code are clear. Instead of describing how to search through the tables, you tell the database what the properties are that you're looking for.
Code that becomes nearly trivial in prolog often would look like some kind of nested case statement with exception handling in C++ for example.
Like many thing in programming, the declarative method is good for some things and less good for others.
You're right, I was hasty about not including efficiency of conversion to mechanical energy.
However, from a fuel usage standpoint, electric power is only about 50% efficient (the best plants reach 60%, most are less), whereas a car is maybe 25%. So let's consider fuel -> mechanical for both systems.
Charging batteries is not very efficient when the batteries are more than say 50 or 60% full already. Your 80% figure is off considerably when you consider that the battery is probably not discharged more than about 50% due to the onboard prius electronics kicking in to keep it from being too low.
With say 60% efficient battery charging, and 80% efficient motor/transmission system you're talking about 48% efficient electricity from wall -> mechanical output efficiency.
With even 60% efficient fuel->wall electricity power plant (ignoring transmission losses), the net fuel-> mechanical efficient of the entire system is about 28%, only marginally better than the 25% you'd expect from a good honda or toyota engine. Interesting. Now the fuel burned at a power plant is cheaper and requires less refining so that's an issue. But it's interesting to see these numbers.
If you just look at dollars, then you've got about 48% efficiency wall electricity -> mechanical and 25% efficiency gasoline -> mechanical so you're using about 2 times as much fuel energy as electricity, so you do save a small amount of dollars, by my calculations around 2 cents per kilowatt hour output. Of course that gets eaten up by the over-baseline charge they put on the excess electricity you're using (over baseline electricity here costs about $0.17/kWh I think.)
At best, considering the time value of money and the premium on hybrids, you're not likely to break even vs buying a reasonably efficient gasoline only car, and you can't really reduce carbon emissions this way without changing the electric generation mechanism.
Now if you want to heat your house with the waste heat of a diesel engine while charging the car battery at night, you could do quite well, in a cold climate.
However the main people involved in this particular article were in California.
In Sweden you have a smallish population with a lot of hydro power, so you're right this could potentially improve things there, even with the taxes you typically pay.
At approximately 112000 BTU/gallon of gasoline that's about 33kWh/gal. In California where the prices are about $0.12/kWh electric, it costs you about $4.00/gallon saved. With gas prices at about $2.40 in CA that's about $1.60 extra per gallon saved.
For those of you who say "fuel savings at any cost" consider that most of the california electricity is generated by burning natural gas, and that there are considerable losses involved in generating and transmitting the electricity.
Nothing to see here at the moment. Wait until the price of gas goes to $5.00 and then buy some solar panels to charge your car (or at least net-meter your electricity).
Emacs's Calc (the full one) Is basically motivated by the HP 48G series of calculators. It's all a high schooler would need to do calculus, graph equations, basic stats, and numerical solutions. Graphing requires gnuplot.
It includes a lot of functionality and it's generally accessed by key combos, so reading the manual is necessary. in particular inputting algebraic formulae requires typing the quote key first.
it will do symbolic and numeric integration and differentiation, and solutions of matrix equations. I use it all the time for basic homework type problems in engineering.
Other software that might be appropriate is maxima, octave, and R. R is especially good for data analysis and statistics.
I don't recommend axiom for high school level, but it is quite good. (type system adds extra complication for high schoolers though).
Or, simply task fuel burning generators off the grid as the solar comes online, but that does require coordination between different types of generators.
The first order analysis says that light bouncing off the white side should cause the white side to recede (change in momentum is larger than when the light is absorbed on the black side).
Does it?
Then you might consider that the black side is hotter, and maybe the low pressure gas molecules bounce off the hot side with more momentum.
Nope.
It turns out that the physics is rather complicated. I can't remember where I read it, but there was a detailed account of the edge vortex or some such thing that produces the effect online somewhere.
Observer B sees it as violation of conservation of energy. So either CofE is wrong, or it won't happen.
I'm not saying that 1) Conservation of energy is true 2) Relativity is true
I'm just saying that they are the best things we have at the moment, they have never been observed to be violated in a definite and irrefutable way.
Therefore unless there is some new data to suggest that these things are not true, pursuing this particular line of research is a poor use of military funds.
Note: as for quantum teleportation, yes a particle or set of particles can appear in location a, and then later appear in location b, without ever being observed between the two locations. However, because we haven't got a satisfactory relativistic quantum theory, it's not clear what is necessary for this to happen over large distances.
However, for a large body to behave this way (as opposed to a few tens or so of atoms or photons or whatever) you have to have them all behaving as one big particle, a mega-boson or something... This sort of research is already being done, and does not relate as far as I can tell to the linked research.
There is good science to suggest that the conservation of energy is real. This has been tested repeatedly.
There is also good science to suggest that the theory of relativity is real, every day in particle accelerators across the world it's used to make predictions that turn out.
The combination of conservation of energy, and relativity suggests that on any largish scale, there can be no teleportation. Of course these things break down when quantum theory is important, but quantum theory seems to be unlikely to be important for the teleportation of large scale objects over large distances.
the way this goes is that conservation of energy (and mass, which is energy in relativity) must be a local phenomena, because if it is non-local, then two different observers will see things differently, one sees that mass a disappears and mass b appears simultaneously at a different spot, another observer moving in a different relative frame will NOT see these as simultaneous, thereby violating conservation of energy since mass b will appear first, then mass a disappear.
when you bring in quantum theory, there is uncertainty involved, and relativity hasn't exactly been melded properly with quantum, so things get a little more muddy, but we're talking about very SMALL effects on the order of 10^-34 joule seconds (hbar).
IN other words, there is already a huge set of scientific evidence against the idea that this is possible.
A) There is no drop in the graph that you suggest. admissions from outside Helena *increased* in 2002.
B) You're right about the possibility of coincidence, which is why the additional associated biochemical studies which show an increase in platelet coagulation and soforth for those exposed to secondhand cigarette smoke is also important. There is a known observed biochemical mechanism at work and it is referenced in the article.
C) The 95% Confidence interval for the change is -31.7 to -0.3. There is only a small chance that the result is coincidental.
D) They discuss the statistical issues, and claim that their evaluation is conservative (that is it doesn't try to account for effects which would be expected to weaken their analysis, ie. a model which took into account the trend towards more and more heart attacks through time would predict an even STRONGER reduction effect for the smoking ban)
Downward forces applied behind the rear wheel will reduce the force on the front wheels where the braking, turning, and acceleration forces are most important. It's a simple matter of calculating the torque around the rear wheel and setting it equal to zero since the car is (hopefully) not going to rotate around the rear wheel. If your goal is to do "wheelies" in your car, it's another story.
In short, although rear mounted fins are helpful on rear wheel drive cars to increase acceleration, they are harmful on front wheel drive cars in almost all cases.
The truth is on these cars that the physics is secondary to the looks.
No need to get testy, but here's a bit of information to clear up some of the issues surrounding this:
An alternator is basically an electric motor run backwards, usually with some kind of voltage regulating circuitry. It produces a voltage on its output. The amount of resistance (aka load) in the circuit determines the current. The alternator itself has some internal resistance.
When the battery is dead, the alternator will force rather large currents into the battery, generally much more than when the battery is rather full. This is the source of the difficulty after jumping a car.
P = I^2R where I is the current and R is the total resistance in the circuit. As you can see having more current produces significantly more power loss in the alternator (which has R in the windings). This power winds up as heat in the alternator (not to mention in other places like the battery or the lights as well).
So all that other stuff notwithstanding, it's a good idea to charge the battery for a while before driving off after getting a jump start. That being said, the resistance of the battery is probably nonlinear, and hence it's the first few minutes that are likely to be the most critical.
In addition, there is no reason to believe that sitting still and revving the engine with the lights on in the parking garage is any less likely to cause alternator failure than driving around with the lights on. The key point is that while the battery is charging for the first 5 minutes or so, don't run additional loads like the lights. Also, don't jump your car started, drive it 1 block and turn it off, run the damn thing for at least 20 minutes to charge the battery enough to start it again.
How little in the way of data analysis skills even tech savvy people have.
Mouse over to see the 64 bit results, on a different scale? Yuck.
Do the test 3 times and take the maximum? Yuck, how about the average?
Bar charts? With non-constant widths between factors? yuck.
I think probably 3 charts would have sufficed to show the whole thing. One showing total sum of time taken to run each of 3 suites: desktop, content, and benchmark, one color per suite.
One showing the effect of 32 vs 64 bits on processors capable of doing both.
One anova of DDR1 vs DDR2 (text) and of Hyperthreading vs. Not.
One plot of performance to price ratio for the best config of each processor.
And don't even get me started on the HINT benchmark (which is hard to get anymore I guess).
1 cent per kilowatthour would kick the living crap out of what we pay here in California. Even before the government went ahead and bought long term contracts in our name at the peak of the distorted market, it was ~ 6 cents per KWH, now it's around 12 or 13 and that's just baseline usage.
somehow I doubt that they're providing wind power at retail prices of 1 cent.
As for storing energy, several mechanisms work well, one is pumping water uphill, and the other is compressing air in underground caverns or old mines. Electrolyzing water to hydrogen and later reconverting it doesn't sound particularly great. Fuel cells are efficient but not long lived.
Big old diesel engines burning hydrogen is a good idea, but I don't know how well it would work in terms of fuel injection, flame propagation, and fuel storage. Metal tanks storing hydrogen become brittle as it diffuses into the crystal lattice. Putting diesel engines in the basements of tall buildings so they can use the waste heat to make hot water and heat the building is an excellent efficient idea though.
When wind is truly 1 cent per kilowatt hour including risk cost (lightning, storms, birds, materials failures) and maintenance I'll be happy to buy a turbine and run it into lead acid batteries to provide all the backup power and uninterruptible computer power I could ever want. Not to mention net metering my utility bill.
You have to consider the MARGINAL food requirements of a human, since the basal metabolic rate will be burned regardless of whether you're on a bike.
Since the BMR for an adult male is approximately 2000 Kcal and riding a bike around at a comfortable pace for 2 hours a day on flat ground costs maybe 250 Kcal according to the data quoted above, what we're talking about is a 13% increase in food consumption. Since healthier people are generally lighter weight and happier, and therefore do not overeat as much, it's possible that a person who bikes for transportation eats less total food than a person who doesn't depending on the rate of overweight people in the relevent populations.
Re:Expensive and inaccurate
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Hmmm... For the most part, you will get an interference pattern at the point of interference with beat frequency 10GHz and carrier frequency 500.05 THz
As the beams diverge they will pass through each other as if they had never interacted.
If you look at what occurs on the quantum level, you will get a mixture of 500.0 and 500.1THz photons interacting with matter in a way that is spatially and temporally determined by the interference pattern caused by the two beams. You will NOT get 10GHz photons to any appreciable degree, unless I'm unaware of some sophisticated quantum effect.
To shorten the pulse length you need to quench the main xenon tube earlier. One way to do this might be to put a smaller flash lamp (available at radio shack?) in series with a smallish capacitor and put those in parallel to the main flash lamp. The goal is to trigger the smaller flash lamp as a turn off circuit, it will divert the current into the small capacitor which will drop the voltage across the main flash lamp causing it to stop conducting. The small capacitor will rapidly charge and hence little energy would be used in turning off the circuit.
Now that you have a main trigger and a quench trigger, you can have your BASIC stamp control the flash duration. A normal flash lasts a millisecond or so, you could probably put this flash very close to your target (perhaps with some plexiglas to protect it) and trigger the flash for say 50-200 microseconds instead giving a much faster stop-motion (though darker picture).
Crank up the CCD sensitivity and bring the flash close and you'd be all set.
Alternatively you could use a pre-built "auto flash" and replace the light sensor with a output line from the BASIC stamp. This would cost more, but be easier from a construction standpoint since the quench design is debugged already.
You may have to put some tape over the sensor, and open the case and control the quench with a clip lead.
The stone is usually spinning around an axis that is more or less vertical. The angular momentum of the stone makes it much more difficult to flip over via forces exerted by the water interface. In order to have it flip over, the axis of the spin now has to become horizontal requiring a tremendous torque.
A stone fired at a lake with no initial spin might easily tumble in the manner you're describing, but probably wouldn't skip nearly as well.
Does anyone know of a live CD based on Debian that is oriented towards scientists and mathematicians? For example something that has Octave, Yacas, Maxima, gnuplot, R, LaTeX, Emacs with calc, etc?
I am considering doing this myself from a morphix lite-gui CD but I don't know enough about how to do it yet. The Morphix docs were not exactly straightforward either.
I think making morphix auto install by wiping the first hard drive would be easy though (per the original question)
Slashdot Mirror
There *IS* a pretty decent benchmark out there which actually correlates well with processing power in terms of data processing speed.
It was called the HINT benchmark and it was developed by a guy at Iowa State University Ames Laboratory. I think they tried to commercialize it but it didn't get off the ground. It was released under the GPL. It's out there in various places.
If you can find a copy of the software then compile it up, and it produces some very interesting data. It produces a curve of "quality improvements per second" as a function of memory usage...
So that the people who were duped don't realize that they were duped by real bad guys, instead they think it was a security audit by good guys, so they take no action.
You should do an economic analysis of the cost of getting a rugged camera vs the cost of simply replacing the cheaper consumer level ones every 9 months or so. Also, consider buying a replacement warranty from some place like Best Buy.
It's got to be cheaper to simply replace the Sony every 9 months using the Best Buy warranty than it is to buy one of those pro dvcams. A typical pro level camera is around $5k and up, so you have to get 10 years of use out of the pro one to make it worthwhile at 0% interest rate. At real interest rates it's even longer life required. Do you really even WANT 10 years of service from a camera? Tech changes faster than that.
Rule based programming's purpose is to solve a problem that requires complicated logic by declaring what the relationships are, instead of describing a procedure that solves the problem.
The advantage in these sorts of uses is that you can reason about the declarative program much easier than you can about the set of steps that you would write down in a procedural language.
SQL is a kind of declarative language that you might be familiar with. Although it is much less powerful than say prolog, its advantages for searching for information over something like a bunch of perl code are clear. Instead of describing how to search through the tables, you tell the database what the properties are that you're looking for.
Code that becomes nearly trivial in prolog often would look like some kind of nested case statement with exception handling in C++ for example.
Like many thing in programming, the declarative method is good for some things and less good for others.
When you have all the power of R to do your statistical plots, why do you go out to ploticus?
It seems very odd to me, but I'd be interested to hear why you prefer Ploticus to the yumminess that is R.
You're right, I was hasty about not including efficiency of conversion to mechanical energy.
However, from a fuel usage standpoint, electric power is only about 50% efficient (the best plants reach 60%, most are less), whereas a car is maybe 25%. So let's consider fuel -> mechanical for both systems.
Charging batteries is not very efficient when the batteries are more than say 50 or 60% full already. Your 80% figure is off considerably when you consider that the battery is probably not discharged more than about 50% due to the onboard prius electronics kicking in to keep it from being too low.
With say 60% efficient battery charging, and 80% efficient motor/transmission system you're talking about 48% efficient electricity from wall -> mechanical output efficiency.
With even 60% efficient fuel->wall electricity power plant (ignoring transmission losses), the net fuel-> mechanical efficient of the entire system is about 28%, only marginally better than the 25% you'd expect from a good honda or toyota engine. Interesting. Now the fuel burned at a power plant is cheaper and requires less refining so that's an issue. But it's interesting to see these numbers.
If you just look at dollars, then you've got about 48% efficiency wall electricity -> mechanical and 25% efficiency gasoline -> mechanical so you're using about 2 times as much fuel energy as electricity, so you do save a small amount of dollars, by my calculations around 2 cents per kilowatt hour output. Of course that gets eaten up by the over-baseline charge they put on the excess electricity you're using (over baseline electricity here costs about $0.17/kWh I think.)
At best, considering the time value of money and the premium on hybrids, you're not likely to break even vs buying a reasonably efficient gasoline only car, and you can't really reduce carbon emissions this way without changing the electric generation mechanism.
Now if you want to heat your house with the waste heat of a diesel engine while charging the car battery at night, you could do quite well, in a cold climate.
Of course, as they say, your mileage may vary.
However the main people involved in this particular article were in California.
In Sweden you have a smallish population with a lot of hydro power, so you're right this could potentially improve things there, even with the taxes you typically pay.
At approximately 112000 BTU/gallon of gasoline that's about 33kWh/gal. In California where the prices are about $0.12/kWh electric, it costs you about $4.00/gallon saved. With gas prices at about $2.40 in CA that's about $1.60 extra per gallon saved.
For those of you who say "fuel savings at any cost" consider that most of the california electricity is generated by burning natural gas, and that there are considerable losses involved in generating and transmitting the electricity.
Nothing to see here at the moment. Wait until the price of gas goes to $5.00 and then buy some solar panels to charge your car (or at least net-meter your electricity).
Emacs's Calc (the full one) Is basically motivated by the HP 48G series of calculators. It's all a high schooler would need to do calculus, graph equations, basic stats, and numerical solutions. Graphing requires gnuplot.
It includes a lot of functionality and it's generally accessed by key combos, so reading the manual is necessary. in particular inputting algebraic formulae requires typing the quote key first.
it will do symbolic and numeric integration and differentiation, and solutions of matrix equations. I use it all the time for basic homework type problems in engineering.
Other software that might be appropriate is maxima, octave, and R. R is especially good for data analysis and statistics.
I don't recommend axiom for high school level, but it is quite good. (type system adds extra complication for high schoolers though).
Or, simply task fuel burning generators off the grid as the solar comes online, but that does require coordination between different types of generators.
The funny thing is that they go the wrong way.
The first order analysis says that light bouncing off the white side should cause the white side to recede (change in momentum is larger than when the light is absorbed on the black side).
Does it?
Then you might consider that the black side is hotter, and maybe the low pressure gas molecules bounce off the hot side with more momentum.
Nope.
It turns out that the physics is rather complicated. I can't remember where I read it, but there was a detailed account of the edge vortex or some such thing that produces the effect online somewhere.
Observer B sees it as violation of conservation of energy. So either CofE is wrong, or it won't happen.
I'm not saying that
1) Conservation of energy is true
2) Relativity is true
I'm just saying that they are the best things we have at the moment, they have never been observed to be violated in a definite and irrefutable way.
Therefore unless there is some new data to suggest that these things are not true, pursuing this particular line of research is a poor use of military funds.
Note: as for quantum teleportation, yes a particle or set of particles can appear in location a, and then later appear in location b, without ever being observed between the two locations. However, because we haven't got a satisfactory relativistic quantum theory, it's not clear what is necessary for this to happen over large distances.
However, for a large body to behave this way (as opposed to a few tens or so of atoms or photons or whatever) you have to have them all behaving as one big particle, a mega-boson or something... This sort of research is already being done, and does not relate as far as I can tell to the linked research.
There is good science to suggest that the conservation of energy is real. This has been tested repeatedly.
There is also good science to suggest that the theory of relativity is real, every day in particle accelerators across the world it's used to make predictions that turn out.
The combination of conservation of energy, and relativity suggests that on any largish scale, there can be no teleportation. Of course these things break down when quantum theory is important, but quantum theory seems to be unlikely to be important for the teleportation of large scale objects over large distances.
the way this goes is that conservation of energy (and mass, which is energy in relativity) must be a local phenomena, because if it is non-local, then two different observers will see things differently, one sees that mass a disappears and mass b appears simultaneously at a different spot, another observer moving in a different relative frame will NOT see these as simultaneous, thereby violating conservation of energy since mass b will appear first, then mass a disappear.
when you bring in quantum theory, there is uncertainty involved, and relativity hasn't exactly been melded properly with quantum, so things get a little more muddy, but we're talking about very SMALL effects on the order of 10^-34 joule seconds (hbar).
IN other words, there is already a huge set of scientific evidence against the idea that this is possible.
A) There is no drop in the graph that you suggest. admissions from outside Helena *increased* in 2002.
B) You're right about the possibility of coincidence, which is why the additional associated biochemical studies which show an increase in platelet coagulation and soforth for those exposed to secondhand cigarette smoke is also important. There is a known observed biochemical mechanism at work and it is referenced in the article.
C) The 95% Confidence interval for the change is -31.7 to -0.3. There is only a small chance that the result is coincidental.
D) They discuss the statistical issues, and claim that their evaluation is conservative (that is it doesn't try to account for effects which would be expected to weaken their analysis, ie. a model which took into account the trend towards more and more heart attacks through time would predict an even STRONGER reduction effect for the smoking ban)
Bullshit Bullshit
There is good scientific evidence that secondhand smoke exposure increases the risk of heart attack in the general population.
Downward forces applied behind the rear wheel will reduce the force on the front wheels where the braking, turning, and acceleration forces are most important. It's a simple matter of calculating the torque around the rear wheel and setting it equal to zero since the car is (hopefully) not going to rotate around the rear wheel. If your goal is to do "wheelies" in your car, it's another story.
In short, although rear mounted fins are helpful on rear wheel drive cars to increase acceleration, they are harmful on front wheel drive cars in almost all cases.
The truth is on these cars that the physics is secondary to the looks.
Pshaw, my next cat will be called "pipe to grep"
No need to get testy, but here's a bit of information to clear up some of the issues surrounding this:
An alternator is basically an electric motor run backwards, usually with some kind of voltage regulating circuitry. It produces a voltage on its output. The amount of resistance (aka load) in the circuit determines the current. The alternator itself has some internal resistance.
When the battery is dead, the alternator will force rather large currents into the battery, generally much more than when the battery is rather full. This is the source of the difficulty after jumping a car.
P = I^2R where I is the current and R is the total resistance in the circuit. As you can see having more current produces significantly more power loss in the alternator (which has R in the windings). This power winds up as heat in the alternator (not to mention in other places like the battery or the lights as well).
So all that other stuff notwithstanding, it's a good idea to charge the battery for a while before driving off after getting a jump start. That being said, the resistance of the battery is probably nonlinear, and hence it's the first few minutes that are likely to be the most critical.
In addition, there is no reason to believe that sitting still and revving the engine with the lights on in the parking garage is any less likely to cause alternator failure than driving around with the lights on. The key point is that while the battery is charging for the first 5 minutes or so, don't run additional loads like the lights. Also, don't jump your car started, drive it 1 block and turn it off, run the damn thing for at least 20 minutes to charge the battery enough to start it again.
How little in the way of data analysis skills even tech savvy people have.
Mouse over to see the 64 bit results, on a different scale? Yuck.
Do the test 3 times and take the maximum? Yuck, how about the average?
Bar charts? With non-constant widths between factors? yuck.
I think probably 3 charts would have sufficed to show the whole thing. One showing total sum of time taken to run each of 3 suites: desktop, content, and benchmark, one color per suite.
One showing the effect of 32 vs 64 bits on processors capable of doing both.
One anova of DDR1 vs DDR2 (text) and of Hyperthreading vs. Not.
One plot of performance to price ratio for the best config of each processor.
And don't even get me started on the HINT benchmark (which is hard to get anymore I guess).
1 cent per kilowatthour would kick the living crap out of what we pay here in California. Even before the government went ahead and bought long term contracts in our name at the peak of the distorted market, it was ~ 6 cents per KWH, now it's around 12 or 13 and that's just baseline usage.
somehow I doubt that they're providing wind power at retail prices of 1 cent.
As for storing energy, several mechanisms work well, one is pumping water uphill, and the other is compressing air in underground caverns or old mines. Electrolyzing water to hydrogen and later reconverting it doesn't sound particularly great. Fuel cells are efficient but not long lived.
Big old diesel engines burning hydrogen is a good idea, but I don't know how well it would work in terms of fuel injection, flame propagation, and fuel storage. Metal tanks storing hydrogen become brittle as it diffuses into the crystal lattice. Putting diesel engines in the basements of tall buildings so they can use the waste heat to make hot water and heat the building is an excellent efficient idea though.
When wind is truly 1 cent per kilowatt hour including risk cost (lightning, storms, birds, materials failures) and maintenance I'll be happy to buy a turbine and run it into lead acid batteries to provide all the backup power and uninterruptible computer power I could ever want. Not to mention net metering my utility bill.
You have to consider the MARGINAL food requirements of a human, since the basal metabolic rate will be burned regardless of whether you're on a bike.
Since the BMR for an adult male is approximately 2000 Kcal and riding a bike around at a comfortable pace for 2 hours a day on flat ground costs maybe 250 Kcal according to the data quoted above, what we're talking about is a 13% increase in food consumption. Since healthier people are generally lighter weight and happier, and therefore do not overeat as much, it's possible that a person who bikes for transportation eats less total food than a person who doesn't depending on the rate of overweight people in the relevent populations.
Hmmm... For the most part, you will get an interference pattern at the point of interference with beat frequency 10GHz and carrier frequency 500.05 THz
As the beams diverge they will pass through each other as if they had never interacted.
If you look at what occurs on the quantum level, you will get a mixture of 500.0 and 500.1THz photons interacting with matter in a way that is spatially and temporally determined by the interference pattern caused by the two beams. You will NOT get 10GHz photons to any appreciable degree, unless I'm unaware of some sophisticated quantum effect.
To shorten the pulse length you need to quench the main xenon tube earlier. One way to do this might be to put a smaller flash lamp (available at radio shack?) in series with a smallish capacitor and put those in parallel to the main flash lamp. The goal is to trigger the smaller flash lamp as a turn off circuit, it will divert the current into the small capacitor which will drop the voltage across the main flash lamp causing it to stop conducting. The small capacitor will rapidly charge and hence little energy would be used in turning off the circuit.
Strobe Faq
Now that you have a main trigger and a quench trigger, you can have your BASIC stamp control the flash duration. A normal flash lasts a millisecond or so, you could probably put this flash very close to your target (perhaps with some plexiglas to protect it) and trigger the flash for say 50-200 microseconds instead giving a much faster stop-motion (though darker picture).
Crank up the CCD sensitivity and bring the flash close and you'd be all set.
Alternatively you could use a pre-built "auto flash" and replace the light sensor with a output line from the BASIC stamp. This would cost more, but be easier from a construction standpoint since the quench design is debugged already.
You may have to put some tape over the sensor, and open the case and control the quench with a clip lead.
The stone is usually spinning around an axis that is more or less vertical. The angular momentum of the stone makes it much more difficult to flip over via forces exerted by the water interface. In order to have it flip over, the axis of the spin now has to become horizontal requiring a tremendous torque.
A stone fired at a lake with no initial spin might easily tumble in the manner you're describing, but probably wouldn't skip nearly as well.
Does anyone know of a live CD based on Debian that is oriented towards scientists and mathematicians? For example something that has Octave, Yacas, Maxima, gnuplot, R, LaTeX, Emacs with calc, etc?
I am considering doing this myself from a morphix lite-gui CD but I don't know enough about how to do it yet. The Morphix docs were not exactly straightforward either.
I think making morphix auto install by wiping the first hard drive would be easy though (per the original question)