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For some reason, Ethanol made from Corn, Barley, or Wheat is ridiculously and terribly expensive.
A pint can cost $20 easily.

Perhaps the energy efficiency isn't all that matters.... if this can reduce the cost of drinkable ethanol to say $0.10 a gallon, and make it widely available --- cheaper than milk at the grocery store.

Grain alcohol in bulk is in the $1-2 per gallon range already - better than milk prices in my region at least. Most people don't drink it pure. The $20/pint price buys you something reportedly much different than pure ethanol. Also there are the taxes for beverages of course.

http://hypertextbook.com/facts...

it would be neither

I am using the golden standard of American science: 100 yards from goal line to goal line, without the end zones.

an American football pitch is 120 yards long.

In America, we have the liberty to throw balls as short or long of a distance as we like. It makes our games (like baseball) much more interesting.

If I'm reading it right, https://www.hydrogen.energy.go... indicates (about page 18) that a system to hold 5.6kg of hydrogen would be about 3k each with mass production. According to http://hypertextbook.com/facts... the energy density of hydrogen is 33.3 kWh/kg, so that 3k tank would hold about 186 kWh worth, but I don't think that takes fuel cell efficiency into account. According to https://www.hydrogen.energy.go... a PEM cell (the only one listed as "portable" is 50-60% efficient, so it would be more like 112 kWh, which (okay, at this point the "if"s are really stretching) ought to push a Tesla Model S 300ish miles. Not bad.

But yeah, as you note, transportation and transfer is extra. I don't know enough to give figures for that, between having to have a large pressurized tank, a bunch of pumps with (probably) individual compressors, and periodic replacement of parts from embrittlement...

The real problem with the study is the inherent lie in the presentation of the study ie the claim of a 29 year analysis. This because year one is no where near the same as year 29 of the study. Think of it as age over time of the people. So year 1 had a huge percentage of he population with zero exposure at the start and only limited exposure there on in. Towards year 29 those most a risk have only limited exposure over time with maximum exposure to that form of radiation ie they are still to young to get a real measure of impact ie consider starting from the year 2000 on, for more realistic exposure, in terms of degree of exposure and number of years being exposed from a young age (using US data http://hypertextbook.com/facts...).

Reality is the most likely period of measure would be when children highly exposed hit their twenties and thirties, so large changes in occurrence would not logically occur until somewhere between the 2020s and 2040s. So the study is really disingenuous. Reality is the countdown for impact is only really starting now and would still be considered early for a population based study. So come back in the year 2030 and see how people feel about his study whether they are acknowledge for the efforts in a positive fashion of whether the population wants them hung, drawn and quartered for spreading false information.

Understanding the equations and implementing them, and even understanding that integration is what you need are the parts that math helps you with

The point is that you don't have to understand them to implement them. You actually need to know very little. Yes, it's helpful, but it's far from essential. That's the point. No one is arguing that you're better-off knowing nothing about math or physics, only that it's not that important for developers even when it superficially appears that that understanding is necessary.

Now we're having a completely different discussion...

How do you make characters move intuitively? By making them inhabit a world that follows physical laws similar to our own.

If I remember correctly, in Super Mario you could move left and right while in the air. That is pretty obviously outside the physical laws of our universe. They did this to give the player more control over their jumps. It feels intuitive, even though it's completely different from the laws of the universe we inhabit.

How do you make sure that a character follows a realistic, predictable, intuitive parabola through the air when they jump?

By abandoning Newton and developing a system that works well for the game. Give it a try. Write a simple side-scroller that accurately reflects the physics of the natural world. You'll be amazed at how terrible it plays. I did a quick search, and found a number of discussions that seem to support this. I also found a few breakdowns that may interest you: Sonic Physics, Super Mario Galaxy Demystified, Mario Gravity, SMB Physics.

That second link has a nice quote: "Obviously, real world physics have a place in today's games. However, they take a backseat to psychology when it comes to making real world gameplay"

Perhaps we can put this issue to rest.

We are a ways away from not being able to shrink dies further using known technologies. One atom, in this context, is much smaller than 10 nm. The range is 0.1 to 0.5 nm using various methods of calculating the atom's diameter (see link following). . Source on atom size: http://hypertextbook.com/facts...

It means they haven't done the math. Heck, even if you covered every square metre of a plane with solar cells you couldn't collect enough power. There's not enough there.

Let's do the math, then. The specifications of Solar Impulse-2 are available as a starting point.

At 269.5 square meters of solar cell coverage, and an average power density of 1.35 kW per square meter, the maximum amount of energy the plane can harvest is about 364 kW. Now, we can use two facts to avoid the ugly world of aeronautical engineering (which I don't know): The aircraft has flown under its own power, supplied by four 17.5-horsepower motors. Those motors therefore supply about 13 kW each, for a total of 52 kW of energy required to fly.

Since 52 kW is far less than the 364 kW the solar cells produce, yes, there is in fact enough power available for collection.

Even if you charged up batteries from ground sources you couldn't carry enough storage and have the plane get off the ground because of the weight. Even with an order of magnitude improvement of power density you couldn't.

As noted, the plane has already flown, carrying its lithium batteries with it.

Weight, energy storage density, and efficiency matters too much for that application for it to be any other way.

Ah, finally some thermodynamics! Currently, the whole plane needs an efficiency of about 15% to simply fly. After some quick research, it seems most solar cell technologies today run at about 20% efficiency, with new technologies pushing 46%. Going from the 20% point, that means the motors need to be only 75% efficient. A bit more research shows that they're actually reasonably assumed to be around 85% efficient. The plane will fly in bright sunlight just fine under solar power alone.

Lithium polymer batteries have efficiencies of around 80% to 90%, so going up to a solar cell with 25% efficiency would allow the plane to either charge or fly, but not both. Double the efficiency and you double the capability, so having solar cells that are 50% efficient would allow both charging and flying under ideal conditions. We're getting pretty close to that.

Throw in some assumptions about duty cycles, allowing the plane to be on the ground for a bit (doubling its charging rate, because it doesn't need to spend energy to fly), and making long trips is feasible in several short hops. Account for an intelligent pilot, using tailwinds and other air currents to reduce the energy needs, and those hops can be made longer.

A Boeing 777 is designed for speed. If you're not in a hurry, solar power might just be a reasonable option very soon.

1. The effective range of a shotgun (ie the range at which the pellets would cause damage) is about 45 m. I can't find a freely accessible authoritative source for the maximum fallout range for shot, but all of the references to those that I can find say that the maximum travel distance of commonly used shot is about 300 m.

Discharging any firearms in city limits is dangerous and likely illegal, but shooting a shotgun on any sizable plot of land is not likely to cause damage to anyone else. Shotguns are regularly used in rural areas worldwide.

2. I totally agree here. A low powered directional EMP could do the trick. I hear the really high end drones even autogyro down.

From the letter signed by Einstein to Roosevelt:

One possible way of achieving this might be for you to entrust with this task a person who has your confidence and who could perhaps serve in an inofficial capacity.His task might comprise the following:
[...]
b) to speed up the experimental work,which is at present being carried on within the limits of the budgets of University laboratories, by providing funds, if such funds be required, through his contacts with y private persons who are willing to make contributions for this cause, and perhaps also by obtaining the co-operation of industrial laboratories which have the necessary equipment.

Which sounds kind of Manhattany to me.

The solar wind might not be all that dense, but I still wouldn't chance the antimatter finding a random ion too close to the launcher.

Depending on the altitude, there's more up there than just the solar wind. The escaped particles from the ionosphere, for one.

Much of the space environment around the earth (in fact in the whole universe) contains plasma at varying densities. Whether an antimatter beam could travel very far in earth orbit would depend on its flux and the ambient mean-free path for the antimatter particles in question. I'm not sure what the numbers would be for antimatter, but some quick Googling reveals that non-exotic matter typically has a mean-free path on the order of 1 m in low earth orbit, 1 AU in interplanetary space, and potentially thousands of light-years in interstellar space.

The solar wind might not be all that dense, but I still wouldn't chance the antimatter finding a random ion too close to the launcher.

EU nations have managed to put up a full service light rail system connecting all your major cities, in an area about as large as the five boroughs of NYC.

The area of NYC is somewhere between 650 sq.km and 950 sq.km, depending on how you measure. There are 44 European countries larger than 1000 sq.km - NYC is only larger than Andorra, Malta, Liechtenstein, San Marino, Monaco and Vatican City. Even the 44th largest on the list, Luxembourg, is more than two and a half times bigger than NYC.

okay, a .22 averages around 1,120 f/s. 3% of that is 33.6 feet per second. That translates to around 23 MPH. Yes, I can see how this highly dangerous weapon might add to the controversy of 3D printed guns. It is only slightly slower than an olympic sprinter running at full tilt.

Space is full of dust on an astronomic scale. On a scale relative to humans, it's a void. When projecting a narrow beam of light through space, the odds of it hitting enough dust to give a visible reflection to an observer is pretty small. The average density of space* is around one atom per cubic centimer. That means you would have to project a laser with a 1cm diameter about three million kilometers before it interacted with enough atoms to constitute a single single spec of dust. That's nearly eight times the distance of the Earth to the moon.

Of course, it might hit high density dust pockets, but those are fairly far about and would just be seen as a few glimmers of light between the projector and the target, certainly not enough to make any sort of line as projected in Science Fiction.

* http://hypertextbook.com/facts/2000/DaWeiCai.shtml

Untrue.

Cell phones have a peak emission power of up to 3W and usually transmit a few 100s of mW.

Source: http://hypertextbook.com/facts/2006/EbruBek.shtml

but I would think 500C is a bit unusual for an engine to operate at. That's roughly 900F, well above the melting point of, say, lead, and getting close to that of aluminum or magnesium.

If you pop open the hood and look along the sides of the engines, you'll notice that even though your block is aluminum, your exhaust manifold is not. The operating temperature of that will vary from 500 to 1000F for a V6 or V8. It will be higher if it is a rotary engine, or turbo-charged. A turbo-charger works by taking the pressure of the exhaust and using that to drive a turbine that compresses air and feeds it into the intake -- as a result, the exhaust will be at a much higher pressure, typically 9-12 PSI, and that results in the excess heat not dissipating as quickly. 1000F is easily attainable in a turbo-charged engine, like those typically found on the higher-end vehicles this refrigerant was/is installed in.

So by the time your engine block has reached 500C, you should already have run a good ways away.

As indicated earlier, the engine block is not the only source of heat under the hood, nor is it the hottest location. Also, the ignition temperature of gasoline can be much lower than 280C -- it can be as low as 232C (495F).

tetraflouropropene sounds like a hard chemical to aerosolize, which is also a condition needed for it to release HF.

It is in a closed loop refrigeration system. The typical pressures for the "high" side of a typical system is 200-350 PSI. Needless to say, a leak in the system would result in already-heated liquid that is designed to vaporize at 15-25 PSI being released into the atmosphere (at zero PSI)... which makes converting it to a gaseous state a simple matter of poking a hole somewhere in either loop; Though it would be somewhat more disasterous on the "high" side of the compressor.

So to recap:
Your understanding of physics is based on incorrect assumptions, and is incomplete as well.

Can't be much more dangerous than gasoline, which can kill you under far less unusual circumstances.

Yes, if you drink it I suppose. But many people have been doused in gasoline and unless they are lit on fire, find that it simply stinks and itches. And in many cases, people have survived being burned by gasoline spills that have caught fire. The same can not be said of anyone exposed to hydrofluoric acid. The CDC has a few things to say about it... namely that it can be used as a chemical weapon and is exceptionally toxic and fatal even in small amounts. Gasoline on the other hand...

http://www.windustry.org/resources/how-much-do-wind-turbines-cost
Most of the commercial-scale turbines installed today are 2 MW in size and cost roughly $3-$4 million installed.

so 9-12 million per 2MW (when you figure out a 33% usage) or 4.5 million - 6 million per MW

----

http://www.powerengineeringint.com/articles/2012/07/chile-suspends-endesas-planned-14-bn-thermal-power-project.html
1.8 million per MW

http://hypertextbook.com/facts/2006/LunChen.shtml
Each ton of coal consumed at an electric power plant produces about 2000 kilowatt hours of electricity (or 2 megawatt hours)

10*24*365/2=43800tons of coal in 10 years

http://www.indexmundi.com/commodities/?commodity=coal-australian&months=60
Seems to be $100 per ton of coal

43800*$100 = 4.38 million

Cost for a new coal power station(including the coal over 10 years) = 6.18 million per MW
----

For solar

http://www.lowenergydevelopments.com.au/index.php?route=product/product&path=69_75&product_id=138
$10,000 for a 5KW system (assuming $1,000 to install)

http://aussiervproducts.com.au/webcontent4.htm
Using 4.5 hours

5kw,10years,4.5 average,365 days
5*10*4.5*365=82,125KWh generated
12.17c/kwh($122/MWh)

Yes it is more then the $50/MWh the generators are getting here but a lot less then >$250/MWh we pay retail.

Using just 2KW locally with no money for the excess would cost you $307/MWh for the system.
The other 3KW that you export (at the $50/MWh) would get you to $229/MWh which is less then the price we pay for grid power.

Car: 2000kg, four tyres, contact patch 86,000mm^2, 2000kg*g/86,000mm^2 ~= 250kPa.

Racing bike with rider: 100kg, two wheels, contact patch 500mm^2, 100kg*g/1000mm^2 ~= 1000kPa.

Woman in high heels: ~2000 to >10,000kPa!

http://auto.howstuffworks.com/question506.htm
http://flocycling.blogspot.co.uk/2011/11/flo-cyling-contact-patch-why-wider-is.html
http://hypertextbook.com/facts/2003/JackGreen.shtml

Did you REALLY think the filament of an ordinary incandescent tungsten bulb operates at 4940.33 degrees Fahrenheit (2727 degrees C)? Seriously?

Um, yeah, I do. Or at least I imagine that it's definitely within the realm of possibility for some light bulbs.

It would take 3 minutes to get to that speed with a constant 1G acceleration and require a 17MW output engine, and would travel 160km while getting up to speed.

You say that like it's a bad thing.

After a hundred miles it's probably used under $200 worth of energy, and 3 minutes!! really - why not chill out and take 10-15 minutes instead.

How many MW output does a normal train have?
http://hypertextbook.com/facts/2001/RadmilaIlyayeva.shtml
6-7.5MW looks like the norm.

Water has no thermal expansion? Really? Basic physics huh?

http://en.wikipedia.org/wiki/Properties_of_water#Density_of_water_and_ice
http://hypertextbook.com/facts/2007/AllenMa.shtml
http://www.youtube.com/watch?v=_Ww6BIy3nc0

And water is actually slightly compressible:
http://ga.water.usgs.gov/edu/compressibility.html

>Doppler radar can actually spot individual raindrops in a cloudburst,

A raindrop, you say? Like what, a big one? Ok, that's 5mm across for the largest type. From here: http://hypertextbook.com/facts/2001/IgorVolynets.shtml

It's only a matter of time that other countries develop "weather radar" as pinpoint as this.

The F22 and F35 radar cross sections have been compared to a metal marble and a metal golf ball, respectively. Their "stealth technology" has just been rendered obsolete.

--
BMO

Why do we need this? The power savings is a plus, but the human brain can only "see" and distinquish an estimated 10 million colors ( http://hypertextbook.com/facts/2006/JenniferLeong.shtml ) and current display technologiy produces 16.7M colors (24-bit True Color). Having a display show 24M colors (50% increase) won't look any different since current technology already exceeds our ability to percieve the differences.

You answered your own question. It's worth it for the Power Savings, IMO, the fact that it shows colors possibly better then we can see them is just the bonus.

Why do we need this? The power savings is a plus, but the human brain can only "see" and distinquish an estimated 10 million colors ( http://hypertextbook.com/facts/2006/JenniferLeong.shtml ) and current display technologiy produces 16.7M colors (24-bit True Color). Having a display show 24M colors (50% increase) won't look any different since current technology already exceeds our ability to percieve the differences.

Teak is pretty dense. In fact if you take a as-cut piece of teak it'll sink in water.

To sink in fresh, pure water at 4c, wood has to have a specific gravity of 1 or higher. True ironwoods meet that requirement. Teak is not an ironwood.

As salt water is ~3.5% denser than fresh water at the same temperature, something that doesn't sink in fresh water isn't going to sink in salt water under the same conditions.

That doesn't mean that it isn't possible to find a particular piece of teak that is heavier than 1 (though this is highly unlikely, teak typically tops out around .75) due to specific growing conditions, and of course water gets less dense as it gets warmer, but I will leave the math to you to figure out just how warm the water has to be for a freshly cut piece of teak to sink. Adding in unknown impurities to the water starts make it challenging (other than salt).

For more homework, examine what kinds of trees grow along coastlines subject to tsunamis (including trunks of trees that could find their way to the sea shore via rivers) and what their specific gravities are. Add in that a trunk of meaningful size can take years to fully saturate, and realize that flotsam comparable to that dock has been crossing oceans far longer than bipedal locomotion has existed.

The person who keeps spamming that trees will quickly absorb water and sink needs to be trolled out of existence (not for doing it once, for doing it repeatedly). Balsa, for example, has a specific gravity of under 200, and it takes longer for water to saturate it enough than it takes to cross the Pacific Ocean. Remember Kon-Tiki?
In fact, had Heyerdahl followed the advice of other sailors, both he and his crew would likely have perished. The sap in the balsa wood prevented the sea water from penetrating the logs and kept them buoyant. Also, as the waves lifted the boat, the ropes used to lash the logs together dug into the soft wood, forming grooves that protected the ropes. Steel cables or wire would have sawed through the logs and left the crew clutching small stumps to survive. Balsa is not the only wood (far from it) capable of such a feat.

Which has nothing to do with whether or not that floating dock should be sold to the highest bidder as scrap, and if the highest bidder wants to put it back into service it must be cleaned/scraped before doing so.

Roll back to 1992. How fast were data connnections for mobile devices at the time? How many people had cell phones? 7M according to: http://hypertextbook.com/facts/2002/BogusiaGrzywac.shtml versus 327M now. The market wasn't that big, the data would suck, lets be realistic touch screens would not be very good back then as would the resolution (heck computers were probably running 1024X768 so what would a cell phone sized screen be?).

I love how whenever someone comes out with something that pushes the edge of what is economically feasible someone pipes up and says "but I had a screen in my lab 10 years ago that was this good" or whatever. Yeah you had a single screen, with a team of grad students to operate it at a cost of 10's of thousands likely.

Another one that happens is people say "yeah but we'd get a large amount of volume and the costs will go down fast". How fast? How many of the 7M people with phones already would be willing to drop their old phone and drop another 1k or so on a phone? In the mean time you bleed red ink in hopes that something good will happen ... later ... somehow. Heck MS revenue was only 2.7B for 1992, they now do ~70B. It would have cost them a large portion of their revenue (not even counting whatever their actual profit is on the revenue) to develop the phone and a large number of people. Instead they locked down a virtual monopoly of desktop OS space which at the time was a much, much larger market. Good choice IMHO.

And while the *de*celeration alone is completely implausible, an *a*cceleration after the stop to regain the same speed again is even more implausible.

Unless it was a custom build drag racer.

A big grain of sand is maybe 0.5 mm in diameter, so 1000 grains of sand is maybe 1/2 a milligram, which isn't much of a beach

Oh, you fail. A miniscule amount of research leads to the conclusion that a grain of sand is 0.67–23 mg, and that a thousand of them could weigh on the order of an ounce (it depends of course on the grade of sand in use, but the order of magnitude is correct).

The seafloor at 10,900m "endures" the water pressure? If the mean density of Earth is 5.52 times that of water, it seems to me that any given portion of the Earth's crust at a depth of 2000m "endures" the same amount of pressure just fine.

Also, the 100A cables are big and chunky (which you need because they reduce the "R" part of IIR losses).

Thickness of wires has nothing to do with R. You use big cables to reduce heating of wires. R is a function of T, where R goes up if you increase temperature. So you don't want your wires to heat up, hence big wires to allow heat to dissipate.

R is constant and depends on length and temperature and material type, not on thickness.

http://hypertextbook.com/facts/2004/BridgetRitter.shtml

PS. Some can argue about high frequency AC and skin conductivity, but that has nothing to do with DC or resistance of material.

This may be of interest: http://hypertextbook.com/facts/2003/BoiLu.shtml

If it is possible to design a house that only consumes http://www.hollowtop.com/cls_html/solar_power.htm - gives them 2500 kWh/year. Uses a bit of real estate but we can get more efficient cells and then the price goes up but you can certainly get more power than this. And it is more than enough if you designed your house the right way. Even without a lot of measures, the average energy use for a Dutch household (2.1 persons) is around 3500 kWh/year. The more modern houses do better. And that is with just the general measures that every house has to follow.

So hopelessly optimistic, I think not. Optimistic yes, but certainly doable with current tech. Maybe not at a pricepoint you'd like, but doable? I think so.

So actually the universe is a big vaccum production facility, and all we see is just a bit of dirt contaminating the otherwise perfect vacuum.
Well, be prepared for the coming of the large vacuum cleaner ... :-)

I wonder what the average density of the universe is. Probably about the same as the best vacuum we can create.

From Wikipedia, I get that the average density of the observable universe is slightly below 10^-26 kg/m^3. On the other hand, the best laboratoy vacuum is a bit above 10^-17 kg/m^3.

In other words, our best vacuum is 9 orders of magnitude worse than the universe as a whole.

4 to 6 Gs for these effects.

Come to think of it, paramecium can move pretty fast, too.

http://hypertextbook.com/facts/2000/RossKrupnik.shtml

2 mm/sec?

I believe it. Those things are a PITA to observe under a scope without adding this slime stuff that slows them down.

Because thought isn't instantaneous, and there is bound to be a delay from when your mind starts the "move a muscle" signal and when that signal actually travels down your spine and to the muscles.

Muscle position signals travel around 100m/sec, so should take only around 20 msec to travel from the brain to the feet. These scientists are claiming to save 130msec from the reaction time, so they aren't just detecting muscle motion nerve impulses.

Hitting the ground or sharp things between the roof and the ground after falling from the roof does kind of scare me.

Yeah, that didn't work very well for Saruman either.

Also since I am not an electronics person how does one make connections to it since I would think that solder would burn paper?

I am an "electronics person" and have accidentally managed to rest my soldering iron against a piece of paper every now and then.
Surprisingly it takes quite a lot of heat to make paper burn when you don't have an open flame to begin with.

It takes right around 451 deg Fahrenheit, sustained.

-AI

http://en.wikipedia.org/wiki/Fahrenheit_451
http://hypertextbook.com/facts/2003/LewisChung.shtml

Paper catches fire around 230 C...

http://hypertextbook.com/facts/2003/LewisChung.shtml

Your silicone should have melted well before the thing goes into combustion...

This is exactly the problem. I don't think most people understand exactly how accurate one part is a billion is. If we're talking that the kilogram artefact has some uncertainty on the order of 10^-6, it should be understood that we can measure (small) distances and time on the order of 10^-9. The IPK was a huge improvement over the "volume of water" concept (which was revolutionary, don't get me wrong). Sure, there's nothing wrong with using a volume of water for a standard if your science is from the 18th century.

This page has some graphs at the bottom that show the temperature-dependence of water's density.

> most technically knowledgeable film editors and sound designers
Clearly optics isn't one of his strengths.

Anything beyond around 20 feet in a dark theater is infinity focus for the human eye and more like 6 feet in daylight.

What this means is your eye focuses the same for any objects 20 feet away or further, Such as when sitting in a theater.

So as long as the 3D isn't projecting images out of the screen at you, your eyes aren't going to notice anything unusual in focusing.

So it's all up to how the 3D content was shot.

Technical details:

What we want to know is the hyper focal distance of the eye,.
http://en.wikipedia.org/wiki/Hyperfocal_distance The closest point of focus at a given aperture, at which infinity falls within the Depth of Field

Optics of the human eye By David A. Atchison, George Smith PG 214 has a nice graph on this.
http://books.google.com/books?id=MHgx-jBA0TAC&lpg=PP11&ots=DGJxkLC644&dq=depth%20of%20field%20human%20eye&lr&pg=PA214#v=onepage&q=depth%20of%20field&f=false

Astronomers the maximum iris opening is 7mm this gives a max aperture is f/3.5.
Wikipedia says f/2.1 to f/8.3 http://en.wikipedia.org/wiki/Apertures

The focal length of the eye is 17 mm http://hypertextbook.com/facts/2002/JuliaKhutoretskaya.shtml

http://en.wikipedia.org/wiki/Hyperfocal_distance
http://www.flickr.com/photos/robertseber/2372620675/ Optimal Aperture For Foreground Sharpness With Infinity Focus
http://www.dofmaster.com/charts.html
http://www.bobatkins.com/photography/technical/dofcalc.html

I have some article on my blog about 3D content issues.
http://videotechnology.blogspot.com/2010/08/thx-and-blufocus-join-forces-to-certify.html
http://videotechnology.blogspot.com/2010/08/why-bad-3d-not-3d-glasses-gives-you.html

Every time corn went in the tank, the miles per gallon plummeted.

Of course, gas has a high energy density, 45 megajoules per kilogram (MJ/kg). Ethanol's energy density is about 25 MJ/kg.

Doing the math on the way home, we discovered that even dollars per mile were way, way up on ethanol gas.

Again of course. Petroleum is cheap, that is unless the lives lost and pollution is added. Heck oil is subsidized beyond deaths and pollution.

I used to love ethanol and went out of my way to find a station with a blend.

Does knowing oil is subsidized too make you feel better?

Falcon

Every time corn went in the tank, the miles per gallon plummeted.

Of course, gas has a high energy density, 45 megajoules per kilogram (MJ/kg). Ethanol's energy density is about 25 MJ/kg.

Doing the math on the way home, we discovered that even dollars per mile were way, way up on ethanol gas.

Again of course. Petroleum is cheap, that is unless the lives lost and pollution is added. Heck oil is subsidized beyond deaths and pollution.

I used to love ethanol and went out of my way to find a station with a blend.

Does knowing oil is subsidized too make you feel better?

Falcon

I looked on their website too. None of it got into details. I wish they would post an energy balance. They say they get 1 litre of oil from 1 kg of plastic. One liter of oil has a mass of .8 kg. An 80% mass conversion rate seems a bit high to me. Though the paper linked below talks about a 3:2 conversion ratio plastic to oil. Or a 1/3 loss in mass, 66% conversion. f it is a revolutionary new pprocess it may work out. However, the paper I am citing speaks of by products such as coke and tar.

On standard barrel oil has a mass of about 138.8 kg. so 1 kg works out to have a value of $0.64, base on *spot* prices. All this makes me a bit dubious. Cold fusion anyone?

reference:
http://hypertextbook.com/facts/2007/ArtemGindin.shtml

Mohammad Nahid Siddiqui, Halim Hamid Redhwi, Catalytic coprocessing of waste plastics and petroleum residue into liquid fuel oils, Journal of Analytical and Applied Pyrolysis, Volume 86, Issue 1, September 2009, Pages 141-147, ISSN 0165-2370, DOI: 10.1016/j.jaap.2009.05.002.
(http://www.sciencedirect.com/science/article/B6TG7-4WBK76Y-3/2/7e1ad7372e75ec73f303bf7419e119fa)

Abstract:
Waste plastics of different types were catalytically coprocessed with petroleum residue of light Arabian crude oil in the presence of a number of catalysts. The purpose of the study was to explore effects of various conditions such as catalyst type, amount of catalyst, reaction time, pressure and temperature on the product distribution. The waste plastic studied included low-density polyethylene (LDPE), high-density polyethylene (HDPE), polystyrene (PS) and polypropylene (PP). A series of single (waster plastic with catalyst) and binary (waste plastic and residue with catalyst) reactions were carried out in an autoclave reactor under variable reaction conditions. The reaction conditions used were 1, 3 and 5 wt.% catalysts, 30-120 min reaction time, 400-430 [degree sign]C reaction temperature and 500-1200 psi hydrogen pressure. The product distribution achieved for residue/plastic/catalyst system showed higher yields of liquid fuels as compared to residue/plastic system. Hydrocarbon gases were formed as well along with heavy oils, insoluble gums and coke. At the reaction conditions of 3 wt.% NiMo catalyst, 90 min reaction time, 1200 psi hydrogen gas pressure, 430 [degree sign]C temperature and residue to plastic feed ratio of 3:2 (wt.) afforded maximum conversion of the plastics into liquid fuel oils.

Keywords: Waste plastic recycling; Coprocessing; Catalysis; Zeolites; Hydrocracking; Residue upgrading; Fuel oils

http://hypertextbook.com/eworld/geocentric.shtml

http://hypertextbook.com/eworld/geocentric.shtml

A compendium of bible quotes loosly supporting this:

http://hypertextbook.com/eworld/geocentric.shtml

... consider the human brain -- a massively parallel 3D processing structure. The brain has an estimated processing power of 38*10^15 operations per second (according to this reference), while consuming about 20 W of power (reference)...

Good point. I believe I have solved Moore's Law in computing for some years. I need shovels, accomplices, and every Roger Corman movie.

First is heat. Volume (a cubic function) grows faster than surface area (a square function). It's hard enough as it is to manage the hotspots on a 2D chip with a heatsink and fan on its largest side. With a small number of z layers, you would at the very least need to make sure the hotspots don't stack.

I'm not saying your point is entirely invalid, however, heat isn't necessarily a problem if you can parallelize the computation. Rather the opposite, in fact. If you decrease clock frequency and voltage, you get a non-linear decrease of power for a linear decrease of processing power. This means two slower cores can produce the same total number of FLOPS as one fast core, while using less power (meaning less heat to dissipate). As an extreme example of where this can get you, consider the human brain -- a massively parallel 3D processing structure. The brain has an estimated processing power of 38*10^15 operations per second (according to this reference), while consuming about 20 W of power (reference). That is several orders of magnitude more operations per watt than current CPU:s have.

I remember solar radation at the earth surface being around 1000 watts/meter.

physics info Oh, 1.353 kW/m2

Must be global cooling..... :-)

For anyone curious, as I was, what the surface temperature of our star is: 5500 degrees C

Which you can derive from noting the Sun's yellow color (approximately 570–590 nm) and applying Planck's Law or Wein's Displacement Law in reverse. Note that this pic shows the 5500 degree C peak aligns well with 500-600 nm.

From the Wein's Displacement article:

" * The surface temperature (or more correctly, the effective temperature) of the Sun is 5778 K. Using Wien's law, this temperature corresponds to a peak emission at a wavelength of 2.89777 million nm K/ 5778 K = 502 nm = about 5000 Å. This wavelength is fairly in the middle of the most sensitive part of land animal visual spectrum acuity. Even nocturnal and twilight-hunting animals must sense light from the waning day and from the moon, which is reflected sunlight with this same wavelength distribution. Also, the average wavelength of starlight maximal power is in this region, due to the sun being in the middle of a common temperature range of stars.

[See for example the article color, because of the spread resulting in white light. Due to the Rayleigh scattering of blue light by the atmosphere this white light is separated somewhat, resulting in a blue sky and a yellow sun]."

[Emphasis mine]

See also:

http://hypertextbook.com/facts/2002/TahirAhmed.shtml