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There's a lot of controversy over the EPA mileage ratings for cars - understating the higher mileages to make the lower mileage SUVs look better. But the real scandal is the EPA emissions ratings.

I looked into buying a 1989 BMW 325i. The EPA said it would produce 9.7 tons of CO2 per year. I thought that was pretty high, especially for a 2864lb vehicle. But when I ran their own numbers, it turns out to cough out just under 93,200 pounds of CO2 per year, almost 5 times the EPA spec.

Their annual 15,000 miles costs them $1625 for regular gas at $2.06, or about 789 gallons. At under 6.5lbs:gal, that's under 5130lbs of gas:year. Some DOE chemists say that the weight of gasoline's carbon (12) plus 2 atmospheric oxygen (2*16) molecules in each product CO2 molecule mean that the CO2 weighs 18 times the input gasoline. The 2864lb car therefore produces just under 92,300lbs CO2 per year, over 32 times its own weight *every year* - almost 700 tons of Greenhouse insulation since it rolled out of its Bavarian nest 15 years ago.

How much of the atmosphere am I tainting? If I used this stuff the fast way, huffing it in my garage (at Standard Temperature and Pressure), its 0.1144lbs:ft^3 would fill a cube about 100 feet on a side. Dispersed to somewhere over 0.033% of the volume of the atmosphere, that's 3000 of those 100' cubes a year - 3 1000' cubes - 3 billion cubic feet - stretching 300,000' to the "top" of the atmosphere (past 50mi), my dirty air stands on 10,000sq': 100' on a side. Every year I cover almost a quarter acre with dirty air that's killing me slowly. In the 15 years it's been burning, it's covered about 3.5 acres; about 300 million Americans doing that would account for half the total CO2 covering the 48 "temperate" states... 100% of the total across my lifetime... if only we kept the CO2 to ourselves.

Over 46 tons of CO2 per year? That's almost *5 times* the car's EPA spec of 19400lbs CO2. Where do they get that number? They claim that they're getting the numbers from the DOE lab "GREET" model - so on top of the 46 tons CO2 spewing from my car, there's production, refining, distribution of gasoline, plus NO2 and methane (CH4) - probably at least 50 tons! If they're using the superlow CO2 ratings in their environmental "planning", maybe we're a lot farther down the road to hell than even sensible alarmists believed. Get Christie Whitman out here - she's got a lot of 'splainin' to do!

There's a lot of controversy over the EPA mileage ratings for cars - understating the higher mileages to make the lower mileage SUVs look better. But the real scandal is the EPA emissions ratings.

I looked into buying a 1989 BMW 325i. The EPA said it would produce 9.7 tons of CO2 per year. I thought that was pretty high, especially for a 2864lb vehicle. But when I ran their own numbers, it turns out to cough out just under 93,200 pounds of CO2 per year, almost 5 times the EPA spec.

Their annual 15,000 miles costs them $1625 for regular gas at $2.06, or about 789 gallons. At under 6.5lbs:gal, that's under 5130lbs of gas:year. Some DOE chemists say that the weight of gasoline's carbon (12) plus 2 atmospheric oxygen (2*16) molecules in each product CO2 molecule mean that the CO2 weighs 18 times the input gasoline. The 2864lb car therefore produces just under 92,300lbs CO2 per year, over 32 times its own weight *every year* - almost 700 tons of Greenhouse insulation since it rolled out of its Bavarian nest 15 years ago.

How much of the atmosphere am I tainting? If I used this stuff the fast way, huffing it in my garage (at Standard Temperature and Pressure), its 0.1144lbs:ft^3 would fill a cube about 100 feet on a side. Dispersed to somewhere over 0.033% of the volume of the atmosphere, that's 3000 of those 100' cubes a year - 3 1000' cubes - 3 billion cubic feet - stretching 300,000' to the "top" of the atmosphere (past 50mi), my dirty air stands on 10,000sq': 100' on a side. Every year I cover almost a quarter acre with dirty air that's killing me slowly. In the 15 years it's been burning, it's covered about 3.5 acres; about 300 million Americans doing that would account for half the total CO2 covering the 48 "temperate" states... 100% of the total across my lifetime... if only we kept the CO2 to ourselves.

Over 46 tons of CO2 per year? That's almost *5 times* the car's EPA spec of 19400lbs CO2. Where do they get that number? They claim that they're getting the numbers from the DOE lab "GREET" model - so on top of the 46 tons CO2 spewing from my car, there's production, refining, distribution of gasoline, plus NO2 and methane (CH4) - probably at least 50 tons! If they're using the superlow CO2 ratings in their environmental "planning", maybe we're a lot farther down the road to hell than even sensible alarmists believed. Get Christie Whitman out here - she's got a lot of 'splainin' to do!

>However, high-quality tube amplifiers have one characteristic that class B transistor amplifiers do not: zero negative feedback.

Of course, for the price of an equivalent tube amp, you can comfortably get a class A full wave transistor amplifier, and still have enough money left to take a cruise to (insert expensive european destination here). So, again, we're back to square 1: Using a DSP to emulate tube harmonics in a solid state amplifier. And, according to this PhD, they can.

So, there's not a lot left to argue about, except for soft clipping (which is mentioned in that abstract). This is something which you never worry about, IMHO, in a solid state amplifier, since you can easily afford one with SO much headroom, you'll light the voice coil in your speaker on fire before you get to the point of clipping.

I think you're confusing ROMIO with something else, but I'm not really sure what that could be, unless it's the "ROM" in CDROM or something. Or maybe you're trying the unfunniest attempt at a funny mod.. evaaar....???

I have not heard anything that YaST was actually GPL'd yet.

It is, according to the RPM on the 9.1 professional install CD.

Where can I download it?

From the main site and mirrors referred to in the original story. I only actually looked at one mirror, but it ought to be in all of them.

Scientists cannot predict earthquakes - otherwise we would not have so many where hundreds or thousands of people get killed, like the recent one in Japan. After an earthquake has happened there are various things geologists look for in the "fault" associated with the earthquake to give some idea of how long it will be till the next one. The "fault" is the part of the earth's crust where two sections are sliding against one another in some fashion. To make real predictions would require knowing the location of all these faults (some kind of map), knowing at what stage each of them is (how much tension there is and what kind of things are preventing the fault from slipping) and how they interact with one another. Even for very carefully studied regions like southern California, we have only a very small fraction of the information that would be needed for true prediction.

It could be argued that it jumps FROM the GROUND to THE SKY although it is too fast to actually see the bolt traveling.

In other words, 6% of the contiguous US land area would have to be covered with windmill farms.

I'm don't claim to be an expert, but that's what it sounds like. Here's a reference within the paper itself that references the 6% figure again:

The amount of windy land available for power class 4 and above is approximately 460,000 square kilometers, or about 6% of the total land area in the contiguous United States. The potential average power from areas with class 4 and higher, which are suitable for development with advanced wind turbine technology, is estimated at 500,000 MW.

(The sizing assumptions fromt he study: 50-m hub height, 10 D x 5 D spacing, 25% efficiency, and 25% power losses.)

Another interesting figure:

Figure 4 shows the contribution that the wind energy of each state could make to meet the total electrical needs of the nation, assuming a moderate land exclusion scenario. North Dakota alone has enough potential energy from windy areas of class 4 and higher to supply 36% of the total 1990 electricity consumption of the 48 contiguous states.

How much does each windmill cost? (I don't know.) How much would a million of them cost?

The AWEA document includes basic information on cost. One of the charts tables shows a 1.65mW rated 71m diameter turbine to cost $1.3M in 2000. They give a capital cost estimate of building a class 4 50MW wind farm at about $1M/MW, with an annual power production (assuming 35% capacity factor) of 150M kWh.

Here's a 2001 study of Comparative Cost Of Wind And Other Energy Sources [PDF]. Citing a table from the California Energy Commission's 1996 Energy Technology Status Report (CEC calculations do not include subsidies or environmental costs), Wind is about even w/ coal (4.0-6.0c/kWh) and *much* cheaper than nuclear (not sure why the CEC's number differs so much from those floated by the Uranium Information Centre). Once externalities [PDF] are figured in of course, wind power is much cheaper than coal.

What would be the effect of taking that much energy out of wind patterns? Would rainfall in the region be affected? Regional temperatures? Flowering plant pollination rates?

I agree, the most common environmental problems seem to those affecting birds and aesthetic, etc. While I don't think that larger climactic changes are a significant concern at the scales we're talking about, it would be nice to see some numbers/empirical research. I haven't, however seen any such portential issues cited it anywhere, from the ANL's Wind EIS's concerns, the UCS, or any of the various reports I've read (I've done searching on Google and Citeseer), which you might expect to see if there were problems. What I have seen shows local net-positive effects in wildlife from reduced emissions in states implementing large-scale wind power. It might be worth doing more research on how Denmark is doing (they're at over 10%+ of their power being generated vy windmills, and aiming for 40-50% by 2030).

I haven't done enough research to actually nail down the numbers of whether it would be able to completely replace coal, but from the research I've done, wind power is actually something that is pretty close to viable in the US (unlike solar) and certainly very viable in other countries.

Of course getting rid of burning coal is great, but our oil consumption problem is really a totally different can of worms (w/ about 45% of the 20.0MMBD last year being gasoline).

Embrittlement resulting from bombardment with neutrons, usually encountered in metals that have been exposed to a neutron flux in the core of a reactor. In steels, neutron embrittlement is evidenced by a rise in the ductile-to-brittle transition temperature. - results of a Google search

It would be naive to think that nuclear engineers are not intimately familiar with this phenomenon. Can you point out an occurance of neutron embrittlement that has gone unchecked and/or caused an accident? Nuclear power has been in use for fifty years. Surely if it were a serious problem, it would have shown itself by now.

Second, I assume that your 2,000 year assessment was by taking an expected uranium reserve of less than 50 years and multiplying by the expected efficiency of IFRs over LWR/BWRs? Unfortunately this fails to take into account the amount of spent fuel sitting in pools at nuclear plants. This is fuel as well and still retains approximately 98% of its energy potential. Yes, the current generation of LWR are that inefficient and current legislation does not allow nuclear fuel reprocessing. I also fails to take into account the aging stockpiles of nuclear weapons. This is fuel as well. Even without getting into uranium collection from the oceans, I'm sorry sir, but the longevity of this fuel source far exceeds two thousand years.

Third, sodium is indeed highly reactive with water and air. But liquid sodium and metallic sodium have been used successfully in various industries for some time. There is a great deal of experience with that substance. As far as the claim, "Every fast-neutron sodium reactor design ever built has had some serious accidents related to sodium," this is false. Yes, there has been the incident in Japan in 1995 -- the Monju reactor accident which caused no deaths, no injuries, and no damage to the reactor itself. The EBR-II, the prototype test bed for IFR/AFR reactors, was in operation for twenty years with a sodium pool. "Every" fast-neutron sodium reactor? By the way, just how many have been built thus far? (I don't know, but it's certainly a very small number -- statistically insignificant)

In response to your plutonium usage as a bomb, it is important to note that not a single bomb has ever been made from traditional nuclear power-generated spent fuel. Ever. In any country. That said, one can make a bomb from Uranium as well. As far as plutonium goes, the plutonium that is most useful to power generation (the heat-generating isotopes) are precisely the kind of plutonium you don't want for weapons. Plutonium-bearing material taken from anywhere in the IFR cycle is so ornery, because of inherent heat, radioactivity and spontaneous neutrons, that making a bomb with it without chemical separation of the plutonium would be essentially impossible - far, far harder than using today's reactor-grade plutonium.

Now keep in mind that plutonium is never intended to leave an IFR. Ever. There are no shipments "to and from" an IFR. There are only shipments "to." The processing facilities are on-site. And the only plutonium to enter the site is plutonium that already exists in the form of spent fuel or weapons. IFR/AFRs, if you completely disregard the power generation qualities, are still the only large-scale method of disposing of transuranics that I am aware of. What's the alternative? Yucca Mountain for 10,000 years?

Once again, because this bears repeating, spent fuel from a nuclear reactor designed solely for power generation has never before been used by any country to make a nuclear weapon . It would be

Integral Fast Reactor? It's supposed to be passively safe, and recycles it's own nuclear waste.

As a geek, I prefer playing with John Conway's Life.

Also, I remember reading a while ago that the earth's helium resources are pretty limited. Any helium that escapes into the atmosphere isn't coming back. Ever.

So, once we use the helium we have, we aren't getting any more. One source says this may happen by 2030.

Found some googled info here and here and here.

So far, they don't compare at all well with various Linux/UNIX implementations. However, I'm sure they'll manage to get their nose under the tent flap where either they paid their way in, or a PHB thinks that it'll leverage his existing stock of desktop machines. My lab built a couple of turnkey systems for the later scenario, where the given reason was that the typing pool cpus could pitch in some cycles to the cluster after hours. What really happened was that the non-com tasked with managing the systems was trained as an MCSE, and he wanted to stick with what he knew, come hell or high water.

Even if abiogenic oil theory is true -- and that's a big if -- it still took 4.5 billion years for enough of it to pool up that it was worth drilling for as an energy source. It's still not renewable.

Of course, my biggest question for the abiogenic oil crowd is, where the hell did the carbon come from in the first place? And where is the carbon coming from that replaces the oil we drill out? Is there some heretofore unknown nuclear reaction by which silicon spontaneously splits into 2 carbon atoms, against both science and common sense? Follow the carbon, and you've answered the question of how rapidly oil renews itself. And right now, the far most likely theory of where the carbon came from was the Earth's surface, where nearly all the carbon on Earth is currently concentrated (in the biosphere).

Oh, and regarding fission, nobody seems to pay attention to passively safe breeder reactor designs. Lefties hate 'em because they're nuclear (even though it eliminates the "waste unsafe for 10,000 years" issue), Righties hate 'em because they can be used to make plutonium (although normally the plutonium is recycled by the reactor as fuel, hence the name "breeder"). They're also a lot more fuel-efficient than the standard "control rods and water" design.

• Catastrophic accidents
• Weapons generation
• Radioactive waste
• Decommissioning costs
• Uranium is non-renewable

So what if a nuclear plant was designed that addressed these issues? Would you still be against it?

By the way, it was. The prototype was called the EBR-II. The reactor type is called an IFR (Integral Fast Reactor). Let's discuss...

Passive safety: safety systems that rely on properties of nature (like gravity) to function correctly rather than computers or complex machinery. Aside from the fact that a Chernobyl-like accident cannot happen in Western countries (the design was fundamentally different -- optimized for weapons production rather than power), Three Mile Island, a far less serious accident, cannot happen either. How can anyone say this with any conviction? Because they tested the Three-Mile scenario. What happened? The reactor quietly shut down.

So let's summarize safety in an IFR. If something went wrong (the heat exchanger pumps stopped working for example), the reactor is "scrammed", the control rods completely isolate the fuel rods. The control rods are suspended by electromagnet above the fuel rods. Cut the power the control rod suspension mechanism and they drop (gravity), stopping the reaction. But let's say the control rods couldn't drop for some reason. The heat would rise, but the sodium pool would distribute the heat so it wasn't simply localized at the fuel, preventing a meltdown of the fuel (incidentally, for those who get this confused, a meltdown means the fuel melted, not that the plant exploded). The fuel rods would expand gradually from the heat (hot things expand...natural property and all that), the density would descrease, and the chain reaction would reach a terminal point where it cannot sustain further reactions. But let's say that somehow failed. The fuel would need to penetrate the sodium pool to expose its radioactivity to the rest of the core facility (not the outside world, the core building). So let's say that the fuel actually got clear of the pool. It would be contained by the main structure. Let's assume that the fuel were working its way through the main concrete shell. More concrete could be poured to supplement any weak spots. And finally note that all of this highly unlikely scenario would take some time to occur. This would be more than enough time to evacuate anyone in the area.

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Re: Weapons use. "The IFR pyroprocess was designed to be 'proliferation resistant'. Simply put, this means that fuel recycled with IFR technology can't be easily used as material for nuclear weapons. Attempts to extract material to produce a nuclear weapon would require a huge, easily detectable, investment in the same type of facilities and equipment that would be required to produce the material directly from spent fuel from any type of reactor."

Only the material coming out of the IFR would have a much lower concentration of transuranics than that of current light water reactors. Which brings me to...

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Radioactive waste. The spent fuel of light water reactors and the nuclear material in nuclear warheads can be used for power generation in an IFR. You'll hear the boneheads at Greenpeace say things like "...the nuclear industry has failed to come up with a solution for what to do with nuclear waste." Utter bullshit. Here is a solution that reuses the spent fuel instead of dumping it in Yucca Mountain, uses it more efficiently so that the remaining isotopes are of types with substantially shorter halflives, and it gives a solution to the existing, decaying stockpiles of nuclear warheads.

-----

Uranium caches, while not a renewable resource, w

• Catastrophic accidents
• Weapons generation
• Radioactive waste
• Decommissioning costs
• Uranium is non-renewable

So what if a nuclear plant was designed that addressed these issues? Would you still be against it?

By the way, it was. The prototype was called the EBR-II. The reactor type is called an IFR (Integral Fast Reactor). Let's discuss...

Passive safety: safety systems that rely on properties of nature (like gravity) to function correctly rather than computers or complex machinery. Aside from the fact that a Chernobyl-like accident cannot happen in Western countries (the design was fundamentally different -- optimized for weapons production rather than power), Three Mile Island, a far less serious accident, cannot happen either. How can anyone say this with any conviction? Because they tested the Three-Mile scenario. What happened? The reactor quietly shut down.

So let's summarize safety in an IFR. If something went wrong (the heat exchanger pumps stopped working for example), the reactor is "scrammed", the control rods completely isolate the fuel rods. The control rods are suspended by electromagnet above the fuel rods. Cut the power the control rod suspension mechanism and they drop (gravity), stopping the reaction. But let's say the control rods couldn't drop for some reason. The heat would rise, but the sodium pool would distribute the heat so it wasn't simply localized at the fuel, preventing a meltdown of the fuel (incidentally, for those who get this confused, a meltdown means the fuel melted, not that the plant exploded). The fuel rods would expand gradually from the heat (hot things expand...natural property and all that), the density would descrease, and the chain reaction would reach a terminal point where it cannot sustain further reactions. But let's say that somehow failed. The fuel would need to penetrate the sodium pool to expose its radioactivity to the rest of the core facility (not the outside world, the core building). So let's say that the fuel actually got clear of the pool. It would be contained by the main structure. Let's assume that the fuel were working its way through the main concrete shell. More concrete could be poured to supplement any weak spots. And finally note that all of this highly unlikely scenario would take some time to occur. This would be more than enough time to evacuate anyone in the area.

-----

Re: Weapons use. "The IFR pyroprocess was designed to be 'proliferation resistant'. Simply put, this means that fuel recycled with IFR technology can't be easily used as material for nuclear weapons. Attempts to extract material to produce a nuclear weapon would require a huge, easily detectable, investment in the same type of facilities and equipment that would be required to produce the material directly from spent fuel from any type of reactor."

Only the material coming out of the IFR would have a much lower concentration of transuranics than that of current light water reactors. Which brings me to...

-----

Radioactive waste. The spent fuel of light water reactors and the nuclear material in nuclear warheads can be used for power generation in an IFR. You'll hear the boneheads at Greenpeace say things like "...the nuclear industry has failed to come up with a solution for what to do with nuclear waste." Utter bullshit. Here is a solution that reuses the spent fuel instead of dumping it in Yucca Mountain, uses it more efficiently so that the remaining isotopes are of types with substantially shorter halflives, and it gives a solution to the existing, decaying stockpiles of nuclear warheads.

-----

Uranium caches, while not a renewable resource, w

Anybody here working/studying in the nuclear field can comment on the state of these reactors and why we do not hear much from them? If the nuclear industry wants to come back, its not by proposing the old designs it will succeed.

For your information the concept of a numerical zero originated in India

Grid computing is not the same thing as distributed computing. You are talking about distributed computing.

Here is a pdf describing what grid computing is.

This sounds like a specific application of the cutting stock problem.

Cutting stock is an interesting integer programming problem.

The airlines particularly, have famously huge integer programming problems.

From what I've heard from friends who are researching the airline problem, there are approximately 800 constraints, and 9 trillion variables.

Another famous integer programming problem is the the travelling salesman problem.

Integer programming is a pretty interesting topic. There's a good deal of theory behind it, but if you just want to model some systems there are plenty of software packages that let you do that too. The most accessible one is probably solverwhich comes with Microsoft Excel.

This sounds like a specific application of the cutting stock problem.

Cutting stock is an interesting integer programming problem.

The airlines particularly, have famously huge integer programming problems.

From what I've heard from friends who are researching the airline problem, there are approximately 800 constraints, and 9 trillion variables.

Another famous integer programming problem is the the travelling salesman problem.

Integer programming is a pretty interesting topic. There's a good deal of theory behind it, but if you just want to model some systems there are plenty of software packages that let you do that too. The most accessible one is probably solverwhich comes with Microsoft Excel.

Plants are green because chlorophyll reflects green light. This means that green light isn't important to photosynthesis. See these links.

And what about meter? It's the most intuitive and natural measure for distances, as one can observe from it's definition: "Metre is the length of the path traveled by light in vacuum during a time interval of ( 1/299792458 ) of a second"

Where did you get that definition? I've always been taught the meter was 1/10,000,000 of the quadrant of the earth's circumference running from the North Pole, to the equator

> Greenhouse gases are far easier to deal with than radioactive waste. Gases like carbon dioxide can be offset by things like trees. Nothing can offset radioactivity, you are stuck with it for millennia.

I actually wasn't thinking about greenhouse gases at all, but now that you mention it, that's another environmental hazard that you don't have to worry about with nuclear power. I was actually thinking about the radioactive isotypes which occur naturally in coal and get released into the atmosphere when it's burned. The radiation released by coal power tends to be a good bit more than that released by nuclear power.

> Nuclear security is not as strong as you might think.

Read my sentence carefully: "Nuclear power makes a tempting terrorist target: blowing up a power station or waste transportation vehicle can easily irradiate millions of people."

Here's a nice piece, which discusses the exaggerated danger of an attack on a nuclear power plant; it's by a conservative think tank (eww!), but the logic is sound. Even if an attack were successful, it wouldn't do all that much damage. It sounds grim, but from a terrorist's perspective there are far easier ways of killing large numbers of people.

When waste is being transported, the radioactive material is already in a fairly stabilized/contained state, and an attack really wouldn't do too much to disperse it.

Once used, nuclear waste needs to be stored. this waste has a half life of thousands of years, and it needs to be put in a place where it cannot harm anyone or anything for this period of time.

Actually, read up on breeder and CANDU reactors. (As a concrete example, Argonne National Laboratory ran the EBR-I/EBR-II/AFR project, a testbed for a passively safe breeder reactor design -- see this sidebar about "burning" nuclear waste and this article about next-gen reactors. I can't squeeze from their site whether or not they ever built the AFR itself, so I'm assuming not.) The reason the waste of traditional fission reactors is radioactive for so long is that everyone's paranoid about recycling it, because it might conceivably be used by technicians at the plant to make plutonium. If the waste byproducts were recycled into breeder reactors, the medium-term byproducts (those with multi-1,000 year halflives) could be broken down into a mix of more stable atoms plus some short-lived (100-ish year HL) waste, which is a lot more reasonable to deal with. Basically, if it's noticeably radioactive, it's better to release that energy in a usable form right now rather than let it sit around leaking that energy into the surroundings for millennia.

Once used, nuclear waste needs to be stored. this waste has a half life of thousands of years, and it needs to be put in a place where it cannot harm anyone or anything for this period of time.

Actually, read up on breeder and CANDU reactors. (As a concrete example, Argonne National Laboratory ran the EBR-I/EBR-II/AFR project, a testbed for a passively safe breeder reactor design -- see this sidebar about "burning" nuclear waste and this article about next-gen reactors. I can't squeeze from their site whether or not they ever built the AFR itself, so I'm assuming not.) The reason the waste of traditional fission reactors is radioactive for so long is that everyone's paranoid about recycling it, because it might conceivably be used by technicians at the plant to make plutonium. If the waste byproducts were recycled into breeder reactors, the medium-term byproducts (those with multi-1,000 year halflives) could be broken down into a mix of more stable atoms plus some short-lived (100-ish year HL) waste, which is a lot more reasonable to deal with. Basically, if it's noticeably radioactive, it's better to release that energy in a usable form right now rather than let it sit around leaking that energy into the surroundings for millennia.

Once used, nuclear waste needs to be stored. this waste has a half life of thousands of years, and it needs to be put in a place where it cannot harm anyone or anything for this period of time.

Actually, read up on breeder and CANDU reactors. (As a concrete example, Argonne National Laboratory ran the EBR-I/EBR-II/AFR project, a testbed for a passively safe breeder reactor design -- see this sidebar about "burning" nuclear waste and this article about next-gen reactors. I can't squeeze from their site whether or not they ever built the AFR itself, so I'm assuming not.) The reason the waste of traditional fission reactors is radioactive for so long is that everyone's paranoid about recycling it, because it might conceivably be used by technicians at the plant to make plutonium. If the waste byproducts were recycled into breeder reactors, the medium-term byproducts (those with multi-1,000 year halflives) could be broken down into a mix of more stable atoms plus some short-lived (100-ish year HL) waste, which is a lot more reasonable to deal with. Basically, if it's noticeably radioactive, it's better to release that energy in a usable form right now rather than let it sit around leaking that energy into the surroundings for millennia.

This .gov site talks about fluoridation of water being a communist plot. For all you tinfoil-hat guys, watch out!

I also miss having an equivelant to the Excel solver utility, which can optimize hundreds of variables at once to minimize/maximize a result.

Whoa! You can't be serious. If you have to optimize something with hundreds of variables, you should look into real programs to do the task. To be frank, results from excel solver are shit. Optimization is a large field of applied mathematics and can't be reduced to MS Excel click-through feature. See for example this and this.

--
Jari

I also miss having an equivelant to the Excel solver utility, which can optimize hundreds of variables at once to minimize/maximize a result.

Whoa! You can't be serious. If you have to optimize something with hundreds of variables, you should look into real programs to do the task. To be frank, results from excel solver are shit. Optimization is a large field of applied mathematics and can't be reduced to MS Excel click-through feature. See for example this and this.

--
Jari

The Energy Research and Development Administration was created in 1974, and spent tax payer dollars (AKA funding) on solar, wind, geothermal and nuclear energy research.

No CO2 emissions. No 10% more sunshine/10% less rain.

Solar?

Americans used 3,720 billion kWh (kilowatt hours) in 2001 according to the Energy Information Administration [doe.gov], a branch of the U.S. Department of Energy [doe.gov]. Yes, that's billion with a 'b'.

From the Wikipedia: "Sunlight provides about 1.36 kilowatts per square meter, and most solar cells are between 8 and 12 percent efficient." There are 9,158,918 square kilometers in the U.S. Each square kilometer is equal to one million square meters (remember 1km = 1,000m; so a square of 1km by 1km is 1,000m by 1,000m).

A kilowatt hour (kWh) is 1 kilowatt of output sustained over one hour.

So, 9,158,918 (number of square kilometers in the U.S.) times 1,000,000 (square meters in a square kilometer) times 0.68 (number of kilowatts with 50% efficiency) to get kilowatt hours. Multiply that by 8 (average number of hours in the day with usable sunlight) times 365 (days in a year).

18,185,947,580,800 kWh. That's more than 3,720,000,000,000 kWh by a factor of five, right? Solved!

Oh...ummm... This assumes that all of the cells are at that 50% laboratory record-setting level as opposed to the ones in use today. If we go off the 8%-12& mark, we're already at the bare minimum for energy requirements with no margin for error.

And this assumes that all of the panels are kept clean; Remember, less power if there's dust and grime on the solar cells.

And this assumes that it's never cloudy/rainy/snowy.

And this assumes that U.S. never increases their power usage from 2001 levels. (Note, I'm not getting into a discussion of the value of energy conservation. It's immaterial here. If you can get all ~300 million Americans to halt the growth of their usage let alone lower it, I will kiss the ground you walk upon.)

And this assumes that materials are sufficiently abundant and practical to build all of those panels.

And leaving things out in the sun for extended periods of time tends to do bad things to most items: sun-bleached hair, ruined paintings, less efficient solar cells, etc. Solar cells drop in efficiency by 2%-5% every year of their operating life; Best case scenario, your solar cell is working at 90% after five years; 80% after twelve years. (Remember, that's 90% of 12%.)

And, most important, this assumes that all the land area in the continental U.S. including Alaska is covered in solar panels! This means no food grown, no basking in the sunlight, an epidemic of Rickets Disease, etc.

Solar is only good for supplementary power generation: lowering the drain on the grid.

It's not about nuclear being warm and fuzzy. It's not about going with the solution with no risks. No technology available to us today can provide even close to all of the power used with 100% safety. Large scale energy is not and will never be 100% safe. However the use of fossil fuels is worse. Fossil fuels emit too many pollutants that get into our air and water.

It's time to bite the bullet and go for the IFRs. Why it is called an "Integral" Fast Reactor? Once the initial fuel is loaded no fuel goes in and no waste comes out for the entire 70 year life cycle. This will greatly reduce the current 90,000 nuclear shipments a year on trains and trucks. At the end of the 70 years, the nuclear "ash" of the IFR needs to be stored for only 300 years as opposed to 30,000. The actinides are used and recycled over and over until they are depleted. Current nuclear waste and the material for nuclear warheads can be reused as fuel for an IFR instead of being dumped in Yucca Mountain. The purity of that fuel once used in an IFR cannot again be easily transformed into weapons-grade material. It is as hard as converting the original uranium ore. If IFRs are implemented, uranium need not be mined for 500 years; Existing stock piles of uranium ore, nuclear waste, and obsolete weapons will be more than adequ

You're right. Not everything on the web is real. However, there is an occasional kernel of truth.

You're right. Not everything on the web is real. However, there is an occasional kernel of truth.

Myth: You can't use solar energy in far northern latitudes.

When it's sunny, yes, you can use it in northern latitudes. What happens during the rainy season? In many northern states, the rainy season is at least half the year. Go on battery the whole time the sun isn't visible? What happens if (when!) the battery goes dead? Americans used

And let's discuss cost. The brochure you presented states that costs are so bad. Last I checked, good solar panels for the home were upwards of $30,000. If you are already paying for a new house, the extra cost of setting up solar is marginal. For folks who are just getting by (everyone with kids in college), $30,000 just isn't there. Costs from environmental damage where we don't immediately see the price tag? That's fair. Absolutely that's a fair statement to make. Then again so is saying, "What about the hidden costs of completely ripping out an established infrastructure in favor of a new one?" Isn't that fair too?

The idea is to minimize the impact of microhydro by following some simple rules. Always leave enough flow in the stream bed for aquatic life. If migratory fish use your stream, make sure that they and their fry can swim past our diversion, and cannot be drawn into the enstock intake. Always put the diverted water back into the same stream bed in a way that does not cause erosion.

Once again, a fair statement. However how is microhydro going to handle the macro scale when you (a) can't pack them closely together and (b) cannot disrupt the normal activity of the surrounding water? Put more in to get more energy? Remember the 1st Law of Thermodynamics. As it is not created nor destroyed, if you use a sufficient amount of energy in one system, that amount is removed from another system. Environmentally sound? Reducing the energy by a significant amount would be environmentally sound? Most of the world's creatures live at or near a coastline. Carefully consider whether or not you want to mess with this substantially.

Nukes produce nuclear waste, and even after spending billions of taxpayer and ratepayer dollars, no acceptable disposal solution has been brought to the table.

This one kills me. First of all, the term "nukes" usually refers to "nuclear weapons." The requirements for nuclear power are dramatically different from those of bombs. You might as well assert that electricity should be banned because electric chairs are made. It has no place in a power generation conversation. Second of all, there are nuclear reactors such as IFR (Integral Fast Reactor) which were designed specifically to address critics' problems with nuclear. It does not rely on coolant, computer control, or human interaction/intervention to prevent accidents; Safety is dependant upon natural phenomena and the laws of physics to operate. The working prototype for IFR conducted a series of tests where coolant was shut off and all of the usual precursors to a meltdown were put into place. No damage. No leakage. Nothing but a safe, controlled shutdown -- without human or computer interaction. This is not hypothetical. This is historical fact. In fact,

Myth: You can't use solar energy in far northern latitudes.

When it's sunny, yes, you can use it in northern latitudes. What happens during the rainy season? In many northern states, the rainy season is at least half the year. Go on battery the whole time the sun isn't visible? What happens if (when!) the battery goes dead? Americans used

And let's discuss cost. The brochure you presented states that costs are so bad. Last I checked, good solar panels for the home were upwards of $30,000. If you are already paying for a new house, the extra cost of setting up solar is marginal. For folks who are just getting by (everyone with kids in college), $30,000 just isn't there. Costs from environmental damage where we don't immediately see the price tag? That's fair. Absolutely that's a fair statement to make. Then again so is saying, "What about the hidden costs of completely ripping out an established infrastructure in favor of a new one?" Isn't that fair too?

The idea is to minimize the impact of microhydro by following some simple rules. Always leave enough flow in the stream bed for aquatic life. If migratory fish use your stream, make sure that they and their fry can swim past our diversion, and cannot be drawn into the enstock intake. Always put the diverted water back into the same stream bed in a way that does not cause erosion.

Once again, a fair statement. However how is microhydro going to handle the macro scale when you (a) can't pack them closely together and (b) cannot disrupt the normal activity of the surrounding water? Put more in to get more energy? Remember the 1st Law of Thermodynamics. As it is not created nor destroyed, if you use a sufficient amount of energy in one system, that amount is removed from another system. Environmentally sound? Reducing the energy by a significant amount would be environmentally sound? Most of the world's creatures live at or near a coastline. Carefully consider whether or not you want to mess with this substantially.

Nukes produce nuclear waste, and even after spending billions of taxpayer and ratepayer dollars, no acceptable disposal solution has been brought to the table.

This one kills me. First of all, the term "nukes" usually refers to "nuclear weapons." The requirements for nuclear power are dramatically different from those of bombs. You might as well assert that electricity should be banned because electric chairs are made. It has no place in a power generation conversation. Second of all, there are nuclear reactors such as IFR (Integral Fast Reactor) which were designed specifically to address critics' problems with nuclear. It does not rely on coolant, computer control, or human interaction/intervention to prevent accidents; Safety is dependant upon natural phenomena and the laws of physics to operate. The working prototype for IFR conducted a series of tests where coolant was shut off and all of the usual precursors to a meltdown were put into place. No damage. No leakage. Nothing but a safe, controlled shutdown -- without human or computer interaction. This is not hypothetical. This is historical fact. In fact,

Then you're arguing that calculus, trigonometry, algebra, square roots, division, multiplication, even addition, that all of it should have been patentable. At one time they were all novel. And there's plenty of novel math being "invented" today, entire feilds.

Hell, the number zero should have been patentable. The number zero was one of the greatest "inventions" of math was the number zero around 300BC.

The big promlem with patenting math/calculations/software is that you are patenting a sequence of thoughts. Any software can be "run" purely by thinking the sequence of thoghts/calculations of that program. It's a common debugging technique programmers use - they "run" the software purely mentally to see what's happening and what's going wrong. Given enough time and effort any program can be run by pure thought.

You can "imagine" a cotton gin, and you can "imagine" it running and processing cotton, but no matter how much you think about it you can never process any cotton.

Any software can actually run purely mentally. And I reject the notion that you can patent a sequence of thoughts. You cannot imprison or sue me for sitting motionless and thinking. I submit that it's unconstituional to even try. I admit the constituion says nothing about "freedom to think", but I submit that a freedom to think is an implicit prerequisit for a freedom of speech.

And just to pile on yet another absurdity, the holes you punch in the paper roll for a player piano - that is software for that player piano machine. That arrangement and sequence of of holes is instructions for the machine to run. Any song is a program. If you can patent software then you can patent a novel song.

There is a fundamental difference between inventing an object and "inventing" information. Objects get patented, information gets copyrighted.

Why should software be the only thing on earth that gets DOUBLE protection? Both patents and copyrights? Patents and copyrights are different things with different rules. They are each carefully balanced systems. By giving double protection you get broken and unbalanced results.

If you really want patents for software then I say we remove copyright protection from software, LOL. It would be a stupid and horribly broken system, but it would still be better than doubling up.
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In contrast, distilled water is actually boiled in a still and the
condensate collected and distributed. Distillation removes both ionic and
nonionic organic contaminants.

I professor showed me the Robbins Algebra proof a while ago. I was going to link here, but first I searched the page for (Score:5, Informative), and there you were :)

Here's an excerpt:

In 1933, E. V. Huntington presented [1,2] the following basis for Boolean algebra:
x + y = y + x. [commutativity]
(x + y) + z = x + (y + z). [associativity]
n(n(x) + y) + n(n(x) + n(y)) = x. [Huntington equation]

Shortly thereafter, Herbert Robbins conjectured that the Huntington equation can be replaced with a simpler one [5]:
n(n(x + y) + n(x + n(y))) = x. [Robbins equation]

Robbins and Huntington could not find a proof. The theorem was proved automatically by EQP, a theorem proving program developed at Argonne National Laboratory.

I professor showed me the Robbins Algebra proof a while ago. I was going to link here, but first I searched the page for (Score:5, Informative), and there you were :)

Here's an excerpt:

In 1933, E. V. Huntington presented [1,2] the following basis for Boolean algebra:
x + y = y + x. [commutativity]
(x + y) + z = x + (y + z). [associativity]
n(n(x) + y) + n(n(x) + n(y)) = x. [Huntington equation]

Shortly thereafter, Herbert Robbins conjectured that the Huntington equation can be replaced with a simpler one [5]:
n(n(x + y) + n(x + n(y))) = x. [Robbins equation]

Robbins and Huntington could not find a proof. The theorem was proved automatically by EQP, a theorem proving program developed at Argonne National Laboratory.

Your point, again?

Here's a helpful illustration to get you started with your doorbell-mouse-computer device. Also see this one

I persistantly wonder why it's a bad thing not to just use the design from a submarine and just put 12 of them in a row, all of the same design, and man them with ex-Navy personnel.

Good idea, but it's already done. Many US power plants actually use reactors designed for submarines.

Argonne National Laboratory maintains a MPI (Message Passing Interface) implementation for parallel computing called MPICH

The National Center for Biotechnology Information(NCBI), run by the NIH, develops a suite of utilities and libraries for developing bioinformatics applications called the NCBI Toolkit

The second statement in quote from parent is false: there are significant pertubations in the orbits of Uranus and Neptune, and also in Pluto's orbit.

No, there aren't.

That said, they're already working on prototypes capable of printing highly durable ceramic parts for vehicles. Yes, it's a young, expensive technology, but it doesn't take too much imagination to see what it could lead to.

Consider, too, that the advent of ceramics-based firearms would render many weapon detection systems obsolete...

Completely? There are pH values outside of 0-14 range.

"So, the answer is, although pH TENDS to range between 1 and 14 for most household chemicals and substances encountered in natural earth conditions, there is nothing which fundamentally restricts it to this range even at 25C."

The Earth vs. Mars Scorecard doesn't mention the Lunokhod missions. Assuming both missions counted as successes, it would bring the score close to a tie.

Isn't the Mars Scorecard missing a player.

The Beagle 2 anyone?

Congratulations on your recent score for Earth. Now we are only behind 17:20.