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Actually DOE has always been deeply involved in high energy (particle physics) research. They fund a number of accelerators, including Fermilab. Its not clear that any of that research would lead to usable energy sources either.

Good so far.

You can see the Dark Energy research as the intersection of high energy physics (DOE) and cosmology (NASA).

Yes, but don't forget that DOE has its own cosmologists, too. The DOE end of JDEM is being handled by Lawrence Berkeley National Laboratory, which has quite a bit of stuff going on in cosmology, mostly under its physics division.

(I do some work with one of the collaborations based there.)

Actually DOE has always been deeply involved in high energy (particle physics) research. They fund a number of accelerators, including Fermilab. Its not clear that any of that research would lead to usable energy sources either.

Good so far.

You can see the Dark Energy research as the intersection of high energy physics (DOE) and cosmology (NASA).

Yes, but don't forget that DOE has its own cosmologists, too. The DOE end of JDEM is being handled by Lawrence Berkeley National Laboratory, which has quite a bit of stuff going on in cosmology, mostly under its physics division.

(I do some work with one of the collaborations based there.)

Why publicize it was just a "weather balloon", yet go to all the apparent trouble to guard it from public view, quickly whisking it away under military guard?

Because it wasn't just a "weather balloon". It was a balloon sent up to monitor Russian nuclear tests. In the late 40's, that's super-duper top-secret stuff - heck, I can almost imagine that they deliberately covered that program up with stories of a flying saucer crash!

And there wasn't a whole lot of trouble taken to guard it from public view. A farmer found a bunch of shiny junk, it got picked up, the local paper ran a story about it, some joker at the Roswell Army Air Field conflated it with recent stories about "flying discs" and issued a press release. Thirty years later, reports of "rubber strips, tinfoil, a rather tough paper and sticks" somehow became wreckage of an alien spacecraft.

The "Witness to Rosell" book published in 2007 lists over 600 people who claim, in some fashion, that it was really some type of UFO that was collected. That's a significant number of people.....

You can find millions of Americans who claim, in some fashion, that a big bearded guy in the sky created the whole universe just a few thousand years ago, including a garden where he put a man made out of clay who is the ancestor of all of humanity. That's a significant number of people. But numbers don't make a belief sensible.

http://standby.lbl.gov/Hometours/HTlebot99/sld022.htm

Average house according to government research: 600kwh/year

I would not call that insignificant.

exactly. here is another article about full spectrum solar cells from 2002:

http://www.lbl.gov/Science-Articles/Archive/MSD-full-spectrum-solar-cell.html

Yes there are: tighter emission standards, higher safety requirements, America's penchant for higher performing engines.

Americans seem to believe that we have higher safety requirements - but its simply not true. The transportation research board http://eetd.lbl.gov/ea/teepa/pdf/TRB_Safety_1-03.pdf (see page 17) shows that import cars are consistently safer for the occupants than are american vehicles. Typical response at this point is, "But we've got SUVs on our roads, of course the foreign cars have better safety numbers" This data is for import vehicles. that is, they were driven on the same roads, with the same conditions, with the same other vehicles, and came out with significantly better safety numbers. How do you say the US has higher safety standards AND say that SUVs create a more dangerous environment to drive in? Real safety standards would improve the safety of everyone.

I use kphone in conjunction with vic video conferencing. I can also recommend openmash for video. You need to make sure that the necessary ports are not blocked and tat you do port forwarding for incoming calls if you have a router. kphone is a real SIP/VoIP client. The SIP protocol does not look you in to a particular vendor (such as the Skype protocol does). However there are SIP providers with a gateway which only accepts certain providers.

I really believe that microgrids - peer-to-peer electricity grids wherein many small-scale power sources are used where optimal - are the answer to this. The big conventional grids lose a lot of electricity to resistance, and have to overproduce to get any redundancy at all. We need to revamp our infrastructure anyway, so why not?

http://news.bbc.co.uk/2/hi/science/nature/4245584.stm
http://certs.lbl.gov/certs-der-micro.html
http://www.ingenia.org.uk/ingenia/articles.aspx?Index=329
http://www.fuelcellmarkets.com/fuel_cell_markets/news_and_information/3,1,1,1,14428.html

You're a little optimistic about data center's approach to their own best interest. There has been quite a bit of work done in the area of data center best practices and not a heck of a lot of interest. For example, hot aisle / cold aisle is still honestly debated and considered a 'new' idea in many legacy data centers. Power is still quite cheap and very low on the site totem pole below connectivity and reliability.

The government acting as a neutral party to collect useful data is hardly meddling. Next you'll decide to rant about them meddling in pharmaceuticals by funding cancer research. The facts of the matter are that datacenter energy use is very poorly understood by owners and considered a negligible cost of the business. When benchmarked, datacenter efficiency has been found to vary by over a factor of two between facilities. Owners don't really know what is efficient - high bills are just part of the business, and competitors aren't willing to share good data on the subject. Hence the need for the government to provide some benchmarks, similar to the flawed, but better than nothing, mpg ratings for cars.

If you read the articles and are damned sure, cite your sources.

I do that quite frequently here and still get modded troll. I can provide evidence until I'm blue in the face, but it doesn't matter when one is on /. surrounded by believers.

I'll take just one example from your link... The "myth" The 'hockey stick' graph has been proven wrong by Michael Le Page. The hockey stick model was demonstrated to produce hockey stick graphs with random data. It was clearly sheer incompetence or an outright fraud. But that's not the most damning evidence.

The most damning evidence is: It never happened. The predictions made never came true. That model was created by Mann in 1999. As everyone here knows, 1998 was an abnormally hot year thanks to el nino. Mann took that anomaly and ran with it, claiming we were witnessing the beginning of runaway exponential global warming. Temperatures have only gone down since 1998.

And they better link to peer-reviewed research that supports the premise. Or we will taunt you a second time...

Who needs peer reviewed papers? Global warmers are in denial of observed reality.

Solution? Do nothing. It's the same 'solution' offered by the head of NASA and other seemingly intelligent people. I mean, what's the hurry? Where is there any evidence that warming is bad?

Ten years ago, the cult was threatening us with the infamous hockey stick. Computer models were predicting "runaway" global warming. According to the IPCC we were on the cusp of exponential warming. "Oh noes!!11one1! We's all gonna DIES!one1!!"

Then something funny happened... Someone noticed that if you took the model and entered random data, it produced the same hockey stick graph. Gee, do tell... of course, they denied, denied, denied that it was a complete fraud. Yet the most damning evidence is that now, almost ten years later, their predictions simply didn't materialize. 1998 was anomalously hot and temps have not rocketed out of control since then.

Frankly, the only problem I see is global warming cultists preaching fire and brimstone, despite having their alarmist predictions disproven by observation repeatedly.

[And yes, before some global warming cultist chimes in... Griffin did later cede to peer pressure and apologize for making those statement, but to my knowledge he has never rescinded those statements.]

Err, blackle is nonsense in the modern world, IMHO.

I'm also a bit non-plussed that the Z is ~122. That's not exactly closed shell range.

I don't understand your comment about zero interaction cross sections because it doesn't agree with the physics I know. If you look at the elastic and total cross sections for hadronic interactions, they are at worst flat at very high energies, and most in fact have a logarithmic rise with energy at very high energies (see, for instance, Table 40.2 for Figure 40.10 in this reference). And things are much different if you consider all the other particle interaction effects. For instance, photons travel at the speed of light and they have a very high interaction cross section; that is how my sunglasses work.

Very high speed charged particles get killed by radiative losses that kick out bremsstrahlung and pair produce like crazy (you don't want to be around all the x-rays and gamma rays that get produced, which is one reason these things are built underground). The neutral particles are unstable and end up decaying into charged particles, so you don't have long-lived very high speed neutrals hanging around either.

I'm not sure what you're talking about with escape velocity. How can the "near light-speed" particles you talk about not have escape velocity (assuming we pretend there is no matter for them to interact so that we can ignore all the dominant energy loss processes) and end up hanging about and not interacting? The particles that don't have escape velocity don't even make it out of the walls of the vacuum chamber.

I would disagree with you that "serious" physicists are worrying too much about this. The ones who work in the field know the physics. It is similar to the speculations about the fusion bomb igniting the atmosphere, where speculation carried on long after the physics was worked out by those who knew how to do the calculations.

Citation Provided: Google search "Robert Liburdy" DOE "Lawrence Berkeley Lab" and Fraud. In case you're too lazy, here's a few links

http://www.ncpa.org/pd/budget/pd081299a.html

http://www.lbl.gov/Publications/Currents/Archive/Aug-13-1999.html#RTFToC4

http://query.nytimes.com/gst/fullpage.html?res=940CE3DB133EF937A15754C0A96F958260&sec=&spon=&pagewanted=all

http://www.sfgate.com/cgi-bin/article.cgi?file=/c/a/2002/07/13/MN242131.DTL

One of the first Cyclotrons is on display, outside in the weather, at the Lawrence Hall of Science in Berkeley, California. The 37 inch Cyclotron is big -- you can climb on it, although you'll get pretty rusty. (In fact, only the magnet's core is on display; the Cyclotron's Dees are missing). For a photo with seven Nobel Laureats standing in front of the ol' beast, see http://dsd.lbl.gov/Seaborg.talks/65th-anniv/27.html

I have heard this claim before and I have yet to see any kind of credible argument for this. The ionization energy loss of a charged particle penetrating matter is proportional to the distance travelled -- so a smaller memory cell may need less energy to "flip" it, but it will also receive less energy by a passing particle. Thus if the aspect ratio (thickness to length) doesn't change, I see no particular reason why smaller transistors should be "more sensitive" to cosmics. To the contrary: a smaller area means they're harder to hit by a passing particle.

As far as I can tell, cosmic rays deposit so-much energy, with such-much probability, per time, per area, for a given slab of silicon -- and making the slab thinner only reduces the energy deposit.

If we keep the thickness constant, we just hit smaller targets. So instead of one bit-flip per week on our 1MB chip, we now get one bit-flip per week on our 1GB chip (which has the same area as the 1MB chip but smaller transistors).

Is there some kind of credible source for the claim that smaller transistors somehow lead to greates sensitivity to cosmics? (And no, I do not consider any kind of claim by anybody in any kind of journal to be "a credible source" if it is merely regurgitating the same claim without somehow backing it up).

We will have the hardware. In 2009 we will already have achieved 1 Petaflops. Experts think that we need 1 Exaflop to be able to simulate completely the activities of the human brain. Looking at when 1 Teraflop was achieved by a supercomputer (10 years ago, http://www.lbl.gov/Science-Articles/Archive/one-teraflop.html), it's perfectly possible that we reach 1 Exaflop in 2029.

But what about the software? Do they really think they have to wire the hardware like a human brain and that's it?

Agreed. My current T42p has survived 3 cups of liquid, several drops, countless accidental power cord yankings, and a car accident that damaged its carrying case pretty thoroughly. Still works wonderfully.

And before that, my family has owned a long line of Thinkpads, all of which still worked up until the butterfly was accidentally stored in the attic one summer with the battery in several years ago. I used it for mobile note-taking and light word processing up through 2003 or 2004.

With the new magnesium roll-cages, they should be nearly invincible when the HD is locked (and the motion-sensing auto-lock seems to work quite well).

I'm not the GP but can answer your question.

You measure the dopler shift of the stars on each side of the galaxy. Waves from stars travelling towards you compress, waves travelling away from you so it helps if galaxy is seen more edge on than top or bottom towards us.

(Of course it won't be perfectly edge on so you have to calculate the component that is edge on to work out actual speeds around the galactic center. The less edge on the more accurate you can be because the component that's edge on is larger). ...which leads to how do you measure doppler shifts.

One way is to look at the spectral lines of light in a star (ie split the light through a prism or diffraction grating). Chemicals that make up the star's surface absorb at precisely known wavelengths. It's actually really easy to do some calculation once you know what wavelength these lines have shifted to. (I did it when I did my astronomy masters. It's basic algebra andsimple equations). The difficult part is building equipment that can measure spectra so accurately. In the early days they'd be literally measuring the difference between wavelengths on glass plates.

http://aether.lbl.gov/www/science/galrotcurve.html
"To make a rotation curve one calculates the rotational velocity of stars along the length of a galaxy by measuring their Doppler shifts, and then plots this quantity versus their respective distance away from the galactic center."

Found it HERE. Says the US loses an estimated 5% to standby power and some countries are upwards of 20% standby power.

If you get killed because you get run over by a truck, they're unsafe.

Good start for this guy. His paper shows spontaneous rather than SASE free electron laser (FEL) radiation (look it up). Gain is needed next. It's not desktop, it takes a full lab or two, but this is much cheaper than billion dollar synchrotrons like the Advnced Light Source. You guys should read more about this stuff. http://loasis.lbl.gov/

The only upside from a manned mission is that we feel all warm and fuzzy when our heroes return from the voyage. Big deal.

I don't know of any fuel on this planet that will take a large enough payload of fuel to Mars for the return trip. Who said they would ever return? At current tech, it's a one way ticket.

You haven't seen any probes sent with enough fuel to return. You won't see it anytime soon. Fuel that is light enough to take, but has enough mass to provide thrust to escape Mars orbital velocity doesn't exist. Nuke has a limitation, as you use the fuel, it drops below critical mass. Shielding the travelers is a problem. Getting enough initial thrust to launch off Mars, then reaching escape velocity without overheating is a problem.

Got any working ideas. Before you post, check the physics involved. A quick crash course in the basics is here.
http://webcast.berkeley.edu/course_details.php?seriesid=1906978373 Watch or listen to Gravity and Satellites 1 & 2. When you understand the amount of energy required to take enough energy and mass to Mars for the return trip with passengers, then feel free to post. Don't forget you need more than just enough fuel to escape Mars, but also enough to slow down to reach Earth. Earth is in a lower orbit. To reach this orbit, you need to slow down.

Deceleration to orbital speeds is required for survivable re-entry. Leaving Mars to return to Earth does include going from an higher solar orbit to a lower orbit and the requirement to reduce kinetic energy to reach the lower orbit. In other words, you will expend fuel just to slow down.

The Moon mission had the advantage of the Moon and Earth are in the same Solar Orbit and return from the moon required only a little energy because of the low lunar gravity. To get to the Moon, there was not the requirement to leave Earths orbit. Going to Mars has none of these advantages. Mars does have lower gravity than Earth, but the requirement to leave Earth Orbit, increase kinetic energy to reach the outer orbit of Mars, land, and relaunch (with atmospheric resistance), reduce kinetic energy, to reach Earth orbit, and reduce kinetic energy for re-entry is simply a physics problem for energy of magnitudes greater proportion than visiting the Moon and returning. The Mars mission can not be done like the Moon mission. They carry way too little fuel.

http://www.muller.lbl.gov/teaching/Physics10/PffP.html

You might make it to Mars, but I doubt you will be returning in my lifetime.

Also Roland doesn't play nice when it comes to photographs. Please compare http://www.scientificblogging.com/news_releases/helium_isotopes_may_uncover_new_geothermal_energy_sources with Roland's blog: http://www.primidi.com/2007/12/02.html#a2025. Btw van Soest has apparently been working on this subject for some time. Check out his publications list on his personal info page http://www-esd.lbl.gov/ESD_staff/van_soest/index.html

• IANANP (I Am Not A Nuclear Physicist)
• YMMV (Your Mileage May Vary)
• TANSTAAFL (There Aint No Such Thing As A Free Lunch)
• GIYF (Google Is Your Friend)

I use the Physics Diet.

It has to work, because it's physics.

This page says the critical point is at 374 celsius.

Oh, that's right. one of the worst factories ever with regard to the environment; an Integrated Circuit Fab. I like it when hippies talk about how perfect solar is. Let's not forget that we need nasty chemicals like Arsenic to make solar cells.

*ahem ahem*

Berkeley Scientists Synthesize Cheap, Easy-to-Make Ultra-thin Photovoltaic Films
40% efficient solar cells to be used for solar electricity
Titania nanotubes could boost solar cell efficiency
Pink solar cells provide green power on the cheap
Carbon nanotubes could help make nanoparticle-based solar cells more efficient and practical.
Quantum Dots Enables New Advances in Solar Cell Industry

Green and cheap enough for ya?

Although to be fair, most of the work I've seen already done in this vein (years ago) did have Lawrence Berkeley National Labs involved, so I guess that includes the feds. Being personally biased towards stuff I've had a hand in, I think the self benchmarking guide at http://hightech.lbl.gov/documents/DATA_CENTERS/Sel f_benchmarking_guide-2.pdf and the design source book for datacenters at http://hightech.lbl.gov/documents/DATA_CENTERS/06_ DataCenters-PGE.pdf are far more interesting than a watered down Congress-critter report. I'm happy to see they mentioned free cooling, an amazing "duh" approach that is inexplicably ignored far too often (get an engineer to design it and the filtration and humidity control in the winter issues are trivial to handle, plus you end up with a net improvement in redundancy). But I'm annoyed at their ASHRAE boiler plate mention of hot aisle/cold aisle - a design approach that can be a Big Deal as far as saving energy goes as long as the fan control is done properly. As a closing note, benchmarking has shown that typically about half the power going into a datacenter goes to keeping it cool. So listen to us mere mechanical engineers if you want to save a buck or million on the power bill...

Although to be fair, most of the work I've seen already done in this vein (years ago) did have Lawrence Berkeley National Labs involved, so I guess that includes the feds. Being personally biased towards stuff I've had a hand in, I think the self benchmarking guide at http://hightech.lbl.gov/documents/DATA_CENTERS/Sel f_benchmarking_guide-2.pdf and the design source book for datacenters at http://hightech.lbl.gov/documents/DATA_CENTERS/06_ DataCenters-PGE.pdf are far more interesting than a watered down Congress-critter report. I'm happy to see they mentioned free cooling, an amazing "duh" approach that is inexplicably ignored far too often (get an engineer to design it and the filtration and humidity control in the winter issues are trivial to handle, plus you end up with a net improvement in redundancy). But I'm annoyed at their ASHRAE boiler plate mention of hot aisle/cold aisle - a design approach that can be a Big Deal as far as saving energy goes as long as the fan control is done properly. As a closing note, benchmarking has shown that typically about half the power going into a datacenter goes to keeping it cool. So listen to us mere mechanical engineers if you want to save a buck or million on the power bill...

On a roof, such cells would require less than half the surface area to produce the same amount of power as today's standard solar panels, which have an efficiency of about 17%.

Actually theres a study out that equates driving while on the cell phone being 400% more likely to get into an accident.

Forbes Article
400% more likely claim supported by Berkely Lab Of course there is the psudeo-science of the Mythbusters as well where they placed a sober driver on the cell phone and a 'drunk' but under the legal limit of 0.8% blood alcohol level and put them both on a closed course and had them navigate it. They did it both sober with no distractions as a control as well I believe. Turns out they both did equally bad. I am not saying it is a perfect experiment (such would require more than 2 test cases) but it does illustrate that distraction or inebriation = bad for driving ability regardless of the exact percentages involved. and another article from The Straight Dope

The first discovery of this cyclicity in the appearence/ disappearence of fossil species or genera was published in approximately 1982 by David Raup and Jack Sepkoski (a project that pre-dates the Alvarezs' KT impact hypothesis). They see a 26 million year cyclicity. (Note - that link is to a proponent of the "Nemesis" hypothesis ; don't take this as endorsement of that theory. But the man provides an accessible summary of Raup & Sepkoski).
A few years later people looked at essentially the same data set through different statistical goggles. They came up with a 24 Ma cycle. Others have come up with figures around 30 million years, from the same data. Now someone is extracting figures of around 64 million years. Whoopy-dee!
As a geologist, I'm perfectly open to this sort of hypothesis. Space effects on life-on-Earth? Hey, I've been to Nordlingen - tick the box that says "space can affect life on Earth". But being open to this sort of idea does not mean accepting any presentation that's made. It's entirely possible that the observed variations in historical biodiversity levels are as much a product of variable preservation as of variable historical biodiversity.
My guess - there's a lot of statistical effort applied to "damp down" the effects of the big spike in extinctions at 63~65 million years ago courtesy of (amongst others) the Chixulub impactor ; but the studies all show a spike in extinction frequencies at half, one, or twice the period of the biggest spike in the data set. That sounds to me like over-correction or under correction of the data, not helped by the data set being one-sided (we don't know biodiversity rates for the next 100 million years).

I think that's one of the biggest problems with people on the warming side. They tend to believe what the "scientists" in the papers tell them.

I've got just enough room on my roof to cover my electric use with 15% efficient silicon PV. I'm excluding about 25% of the south side which is shaded. Many of my customers use twice as much electricity as I do, but also have bigger houses. Some of them will be running up against 10 kW limits imposed by some utilities on net metering systems but others may not have enough roof and will need to put a portion of of their systems in the yard if they want full coverage of their electric use. Our systems or OK to split up because they go to AC at the panels.

If this new material is only 7% efficient, then people may only cover half of their electric use with roof mounted system. The lower cost will only help with a portion of their electric bill.

Because of this possible lack of fit for the new material, I suspect that silicon will hold its own for a while in the residential market. The place to look for an alternative may be in 40% efficient materials combined with moderate concentration of sunlight.

On the other hand, material that is less efficient but also less expensive could get a lot of use on commercial buildings where the interest is to get some extra use out of a roof or parking lot. In this case the purpose of the property is to make money rather than to provide comfort so the aesthetic issues are different and the financial issues may work out well.

You can sign up for silicon now at http://mdsolar.blogspot.com/2007/01/slashdot-users -selling-solar.html

Sure, straight from the PDG, tests of CPT invariance.

http://pdg.lbl.gov/2006/tables/conlaw.pdf

As you say, very impressive indeed.

Cheers

Martin

Incandescents and the sun give off yellowish light.

No, the sun gives off pure white light by definition. (That's why we have evolved to see that spectrum as the neutral colour. If you look at the spectrum, arguably it's actually a shade of green.) The reason the sun looks yellow in the sky is because the blue light has been scattered away by the atmosphere, making the sky look blue; the remaining (less scattered) light looks yellow as a result. However, if you look at a piece of white paper in the sunlight, it looks white because the yellow light directly from the sun combines with the blue light from the sky and adds back up to pure white again.

The reason people prefer "warm" yellow light is purely emotional as far as I know. It reminds them of campfires and candles.

The LEDs also produced more lumens per watt power consumption as well as used the lest amount of energy to turn on, whereas the traditional florescents had a 7x power spike for turn on, and the traditionals had a 1.5x spike, even the CFL's had a power spike. Everything says to use LED lights now.


Unfortunately we live in a market economy. The cost is a real factor. My average lamp is 900 Lumens. My 1 watt flashlight is only 32 lumens.

If I live another 30 years in my present home, what is the cost to outfit a 6 bedroom 3 bedroom home with LED lamps and will I have any savings over CF bulbs I now have installed?

LED lamps are about 20 cents / Lumen.
Refrence PDF alert. http://www.aceee.org/pubs/a042_l11.pdf

At 5 lamps in the kitchen overhead, 2 under the microwave, 5 in the dining room, 4 in the living room, 15 in bathrooms, 12 in bedrooms, 6 in porch and drive, 4 in the laundry, 2 in the hallway, and 5 in the rec room. Average size 60 watt equivelant. Total numbers of lamps is 60 for a total of 54,000 lumens needed.

To make matters of finding a proper replacement, many LED's are not rated in Lumens but intensity. I don't need a spot of light on the celing above the light. I want the room lit up. Remember there are aproximately 1,000 Mcd to a Lumen. Using that compare this bulb to a typical 14 watt CF lamp.

http://item.express.ebay.com/Home-Garden_Lighting- Ceiling-Fans__16000-MCD-P60-48-White-LED-110-V-Edi son-Type-Light-Bulb_W0QQitemZ220015435889QQihZ012Q QddnZHomeQ20Q26Q20GardenQQadnZLightingQ20Q26Q20Cei lingQ20FansQQcmdZExpressItem

I don't think a 16 lumen lamp is a direct replacement for a 14 watt CF lamp of nearly 900 lumens.

The LEDs also produced more lumens per watt power consumption

http://members.misty.com/don/lede.html
"The better usual modern white LEDs (as of September 2006) produce about 29-45 lumens of light per watt of electricity

http://hes.lbl.gov/hes/makingithappen/no_regrets/l ighting.html

"while the fluorescent produces over 50 lumens per watt"

The high effeciency LED's just are not on the market yet for most white LED's.

I'll stick with CF's as the additional cost of LED's don't yet produce a measurable savings. I have been watching the lumens/watt and cost race for some time. It's getting close, but the average modern white LED is still not as effecient as a typical CF lamp.

A laboratory prototype of a white LED achieving 150 lumens/watt has been announced on 12/20/2006.

Wake me when these are on the shelf at a competitive price.

Oh come on. We're comparing it to the Prius not some abstract "new car". And yes, you paid extra for AC in the VX and it only had a driver's side airbag. But you lose those amenities for a reason. They consume power and the VX was optimized for gas mieage. Glancing through the interior dimensions of the two vehicles, the Prius was slightly roomier in the front seats and cargo, and far roomier in the rear seat (see Honda Civic VX versus Toyota Prius). The engine of the VX was less powerful at 92 HP versus 76HP for the Prius plus a 67 HP electric engine. But curb weight of the VX is more than 800 pounds less. It weighed 2094 pounds curb weight (minus AC) to the Prius's 2932 pounds including AC. That yields slightly weaker power per weight (about 10% less), but performance degrades faster as cargo weight increases. This wasn't the vehicle to efficiently move five big people plus cargo in hilly country.

The premise is flawed. It would seem that calculating the last digit of pi would involve calculating pi out to the last digit:

3
3.1
3.14
3.142
3.1416
3.14159 and so on, until the last digit is reached. Pi is infinite, so the calculation grows and grows until the physical limits of the PS3 are reached.

But it's possible to calculate the nth binary digit of pi without first calculating the preveious (n-1> digits. Since there is no final digit, n is undefined, and thus the calculation cannot even begin. The load on the processor remains zero, and the PS3's power remains in reserve. The PS3 is also capable of determining whether a problem is NP or P, before wasting its time calculating things for puny humans.

The 500 pound gorilla in the corner is that in a typical Silicon Valley datacenter only 50-60% of the power goes to the computers while the other half goes to the support equipment. It does not have to be this way, and things are changing. I have not yet walked into a datacenter that could not cut its total power usage by at least 25% (albeit, in some cases the design damage is done and the simple payback required to make it work would stretch to 4-5 years)(I'm looking at you, datacenters with dozens of 20-30 ton air-cooled compressors on the roof).

On the gross kWh/yr side, the vast majority of datacenters are unable to use outside air directly for cooling. A 24 hour a day load and they can't 'open the windows' to cool it at night (with appropriate filtration and redundant humidity control lockouts of course)? Come on people! It would even improve reliability (even 70F outdoor air could hold a well configured hot aisle/cold aisle datacenter). But that doesn't help trimming peak load, to do that you have to get the airflow right.

Efficiency in datacenters starts with just a basic understanding of airflow. You want it very hot behind the racks; you want that hot air to go directly back to your cooling unit not get recirc'd to a rack intake. And you have to have airflow controlled based on the cold aisle temperature to harvest energy savings (fan energy wastage is ridiculous in these things)(oh, and watch out for those server fans that ramp up if you push the cold aisle temp too high - not efficient to provoke a rack of those guys to start screaming).

You have to know hot aisle / cold aisle to properly design and operate an efficient datacenter, even if that exact configuration is not applicable. Period.

Of course, its not "that simple," but to the design engineers it certainly should be pretty straightforward work. The information is out there and more is in the pipeline. A good start on the basics of efficient datacenters is available here (full disclosure, I was associated with producing that report, so I am not impartial)(but don't blame me for the blurry graphics - I did not create the pdf!).

And for god's sake people, quit keeping these places at 55-60F - I'm freezing my butt off and you're making a mockery of your own 'tight humidity control' (70-90% RH at the server intakes, but a good 45% +/- 2% at the air handler return).

A student at The Univ. of California, Santa Barbara just presented research showing the use of multi-junction devices using Gallium Nitride. This is awesome because Nitride materials are very well suited for a HUGE amount of the sun's radiation, and since he managed to perfect a way of sticking several layers of differently absorbing Nitride Materials together in ONE device, we could theoretically see solar cells that absorb the Entire spectrum of the sun's rays in the near future!

Here's some links:

Indium-Gallium-Nitride can be made to absorb the entire spectrum of solar rays:
http://www.lbl.gov/Science-Articles/Archive/MSD-fu ll-spectrum-solar-cell.html

Tunnel Junctions - this is how you stick together many different layers of material, each layer with their own optimal absorption range (in terms of wavelength, aka. color):
http://www.hitachi-cable.co.jp/ICSFiles/afieldfile /2005/11/28/review07.pdf
(sorry, this is the best I could do, there was no simple paper explaining a tunnel junction. "tunnel" is for electron tunneling...)

In essence, you have different layers that absorb only one range of wavelengths (colors of light), and whatever isn't absorbed goes straight through, and the next layer absorbs another range, etc. etc.

As an aside, did you ever wonder how blue LEDs & lasers finally managed to get working? Nitrides paved the way for emission (and absorption) in a range of visible wavelengths, including blue. This is also why they're great for this application.

Your model (a heat engine) doesn't really work for solar cells, although you are certainly correct that 100% efficiencies are unobtainable.
In solar cells, the point is that photons excite valence electrons across a barrier, giving them enough energy to create a current. There isn't really a classical analogy for this effect.
There's a limited discussion of solar cell efficiencies here, although it doesn't talk much about the underlying physics:
http://www.lbl.gov/Science-Articles/Archive/MSD-fu ll-spectrum-solar-cell.html
The upshot is, cells of a single type of material can only get up to about 30% efficiency, but we can stick several materials together to get past that barrier.

Aren't you being hard on that poor stereo? I mean, it has to power an infrared receiver so that the remote control will work. According to this government study, the IR receiver alone uses 0.05 watts all by itself! Once you factor in the overhead, all the wires and circuits and ohms and such, 22 watts makes complete sense.





Yep. Complete sense...

Using dcraw and the Radiance (HDR) file format, it should be trivial to convert any digicam or SLR's raw image to an HDR.

For manually-captured bracketed images, there's AHDRIC (disclaimer: I wrote this). As long as the EXIF info is intact and the only thing that changes between shots is the shutterspeed, this should do the trick. A related tool (AHDRIA) lets you capture HDRs automatically by controlling a digicam via USB (Canon digicams only, sorry). This process can take 20-120 seconds, depending on the quality required.

"We believe we can [get to 10 GB]...

Also, TFA links to an illustrated version of the story.

I counter-quote, from http://aether.lbl.gov/www/personnel/Smoot-bio.html :
"Much of the excitement outside of the scientific world stemmed from Smoot's comment at the press conference that "if you're religious, it's like seeing God." Smoot did not intend to imply that the discovery offered proof of God's existence, but other scientists, nevertheless, added to the religious metaphors."

One of the most fundamental limitations on solar cell efficiency is the band gap of the semiconductor from which the cell is made. In a photovoltaic cell, negatively doped (n-type) material, with extra electrons in its otherwise empty conduction band, makes a junction with positively doped (p-type) material, with extra holes in the band otherwise filled with valence electrons. Incoming photons of the right energy -- that is, the right color of light -- knock electrons loose and leave holes; both migrate in the junction's electric field to form a current. Photons with less energy than the band gap slip right through. For example, red light photons are not absorbed by high-band-gap semiconductors. While photons with energy higher than the band gap are absorbed -- for example, blue light photons in a low-band gap semiconductor -- their excess energy is wasted as heat.

The maximum efficiency a solar cell made from a single material can achieve in converting light to electrical power is about 30 percent; the best efficiency actually achieved is about 25 percent. To do better, researchers and manufacturers stack different band gap materials in multijunction cells.

Dozens of different layers could be stacked to catch photons at all energies, reaching efficiencies better than 70 percent, but too many problems intervene. When crystal lattices differ too much, for example, strain damages the crystals. The most efficient multijunction solar cell yet made -- 30 percent, out of a possible 50 percent efficiency -- has just two layers.