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In fact, I just did some rough calculations. Consider a really big dinosaur at 23m length. From looking at the picture, we can conclude scientifically that it was about 18m from brain to ass. Now, assuming dinosaurs had nerves similar to ours, they ranged in transmission speed from 20-100 m/s. Even for the fastest nerves, we're talking about a 200ms latency to the rear legs and tail. For humans, that would be a 20ms latency to the toes. For the slowest nerves, it's 1000ms for the dinosaur and 100ms for the human. That's a pretty significant difference and I imagine their bodies would have to function differently in some fundamental ways to compensate for that. I wonder what blue whales do about the problem, or those enormous squid that some people claim to have seen.

Get the freakin' thing upset, and BOOOM.... bits of insect/fish dripping down your walls....

However, that's not how most people are killed by electricity. What kills people is having a small current flow across their heart, causing it to fibrillate and then you die. Your skin is a reasonably good insulator, so this requires a high voltage (NOT CURRENT!) ... 50v isn't enough, and even 100 volts is rarely enough. Given enough voltage, this only requires a small fraction of an amp.

Remember the old saw: "it's the volts that jolts, but the mills that kills".

42 volts will make you jump - I work in the telecomms industry and know what 48 feels like - but you would have to take some care to get enough current from a 42 volt supply through your heart to kill you. It would be a terribly inefficient way to commit suicide. Electric chairs typically use about 2000 volts Amazing (and kinda sad) what you can find with Google!

...laura

...at least if you use a non-ethernet addressing scheme for those bottom 64 bits and get a full 128-bit space.
I once wondered about whether nanotech would present problems for 128-bit addressing and did some back-of-the-envelope calculations to examine the issue. A little math to satisfy one's "what-if geek" tendencies:

earth's surface area = 5.1*10^11 m2
earth's land area = 1.483*10^11 m2

That's surface area, but we live in a volumetric space; let's define that space as 1 km high above/below earth's land-mass(part of that 1km being underground, part being in the air.) Thus the volume of human space above/below land is 1.48*10^14 m3. With 10^6 cubic centimeters per cubic meter, and approximately 10^23 atoms per cubic centimeter, we get 1.48*10^43 atoms in our human-habitable slab of space on earth.

Now, how many IP addresses for that space? Well, 2^128 = 3.4*10^38th.

Ergo we have enough IP addresses for nanotech devices of 43,600 atoms each, in a human-habitable volume completely covering the land-mass of Earth and extending to fill a volume of space above and below the earth's surface for a full 1 km. Sure, you might get nanodevices smaller than that, but would they be independent enough and sensing/generating enough information to communicate via IP?

Well, if that isn't a problem for 128-bits, what is? Let's check a few other test cases that your friendly sci-fi reader might imagine...

Well, that was just land-mass. What if we filled the sea with nanodevices, would that exhaust it?
The sea is 11km deep at worst, 3.8km on average. Water surface area is little over double land. Thus water basically requires a factor of 10x more devices. Given that you probably won't have more than 10% of the volume of any space being nanodevices (and this would seem to remain an extreme upper bound), this probably isn't an issue.

So what about interplanetary colonization? Still not too much of an issue for this solar system (ignoring the latency issues.) At least the first few planets (Mars/Venus/Mercury) which only add a factor of 3-4x expansion once 100% colonized form due to the roughly similar size of available nanodevice space on those planets as earth. True, a colonized Jupiter might pose problems down the line...

And if you used nanoprobes to fill/convert entire atmospheric systems, you end up covering a lot more volume (99% of earths' atmosphere fills approx 8.6*10^19 m3 by my calculations, five orders of magnitude more space than our 1 km slab.) Of course, any nanodevice design on that scale would probably use its own non-IP protocol.

Ah, but what other assumptions could be misleading us? For example, what is the efficiency of the 128-bit name space? Can we really use all those addresses? Well, I admit, I'm less an expert on this. The issue that Ethernet MACs will typically be your bottom 64-bits definitely chews up a lot of space, but if Ethernet doesn't make sense for nanodevices, we'll probably be using something else, or our self-assembling nanoprobes will build and configure themselves so that they share 1 higher-level IP but under the covers each have an colony-wide (not globally) unique ethernet address. How efficiently allocated is the rest of that (non-Ethernet) space? Well, I think CIDR-like tweaks can squeeze a fair amount out.

Still, even in the case where 128-bits isn't quite enough(!), I suspect reverting to NAT-type approaches in IPv6 will be workable. Certainly inter-stellar communications which will be limited to a relatively small number of transmitters will scale up with NATs for quite a while, assuming photon-based communications. ;-)

So I suspect the 128-bit addressing scheme of IPv6 will last us at least another 200 years, not just "decades" as

Just though I should fire up the old google and check it out for myself, here's what I found:

"While the largest Homo erectus brains were about 1250 ml (2 imperial pints) and modern brains average about 1200 - 1500 ml in volume, female Neanderthal brains were about 1300 ml and those of males about 1600 ml, extending to 1740 ml in the Amud man." --Stringer, Christopher & Gamble, Clive. In Search of the Neanderthals. New York: Thames & Hudson, 1993. link

"The Neanderthals were fully bipedal and had a slightly larger average brain capacity than that of a typical modern human (though the brain structure was organised somewhat differently)." --link

A good discussion and some comparisons here: link

Of course by the time I've read it all and wrote this, someone might have posted some relevant information already. Just though I'd share anyway.

Secondly, one point I think needs to be raised whenever the concept of hydrogen fusion as an energy source comes up is (and I do not take credit for this, although I cannot cite the source, I did read it somewhere) if we as a species found a cheap and viable source of energy, there could be long-term enviromental consecquences, even if the production was emissionless in the traditional sense.

What I mean is, although the "global warming" which concerns many people now is due to greenhouse gasses from the combustion of fossil fuels, a cheap and limitless source of electrical energy could begin a new type of global warming; one caused simply by the amount of energy we are adding to our planet as a basically closed system.

For comparison, the energy density of the sun's rays is 1.4 kW/m^2. Multiplying that by half of the surface area of the earth, 2.55E14 m^2 gives us approximately 3.57E14 kW. That's 357000 Terawatts coming in from the sun. Compared to that, all the energy we extract from fossil fuels is insignificant. But if fusion were available as a practically limitless source of power, it's not hard to imagine producing a sizable percentage of that amount within a short (geologically speaking) amount of time.

Whenever you "produce" (release from storage, either in hydrocarbon chains, or in inter-atomic forces) energy and transform it into electricity, it will eventually end up as heat. Even if you go fusion-electricity-hydrogen gas-mechanical energy ... the eventual result is heat.

Just something to think about...

Welcome to my web page on how to make a simple ECG (electrocardiograph - also known as an EKG). Here you will find information how how to build one with less than $10 in parts. But before we get started, let's take a moment to talk about shop safety. Be sure to read, understand, and follow all of the safety rules that come with your power tools. Knowing how ....ummmmm, sorry. I guess I got into a little New Yankee Workshop moment there. :) Anyways, I do want to talk about safety. This device requires you to strap electrodes across your chest. This is inherently dangerous. Both because of the pain caused by sticky tape pulling hairs out of a person's body and also because even small currents can kill. Do not attempt this experiment if you are not comfortable around electrical devices. I am not responsible for any harm you may cause yourself. I have done everything I can think of to make this safe, but don't come crying to me if you find yourself dead.

Now that I've started with this positive note, I can begin. I've split my web page into two sections. One for the impatient - who would like to make their own NOW. And the other for people who would like a little commentary from me. Oh, and those of you who just want to see the final product and don't care about the details, just skip to the Results. Happy reading!

Quick Details on building your own ECG

In Depth Information about my ECG

Introduction - What is an ECG? History behind it. What was I thinking?!

Some Stuff Sought Out - Miscellaneous things that I needed but didn't have

Adventures in Analog Land - The primary amplification circuit - all good ol' analog

Plenty of Programming - The visual basic source

Results - Maybe it's not perfect, but I think it's COOL!

Future thoughts - I still think I'm perfect, but I'm ready to argue these specifics

Notes - I didn't make this all up. Here's proof!

Not bad for about two weeks of work, eh? If any of you have any comments, questions, insults, etc; please email me. Thanks for coming.

Welcome to my web page on how to make a simple ECG (electrocardiograph - also known as an EKG). Here you will find information how how to build one with less than $10 in parts. But before we get started, let's take a moment to talk about shop safety. Be sure to read, understand, and follow all of the safety rules that come with your power tools. Knowing how ....ummmmm, sorry. I guess I got into a little New Yankee Workshop moment there. :) Anyways, I do want to talk about safety. This device requires you to strap electrodes across your chest. This is inherently dangerous. Both because of the pain caused by sticky tape pulling hairs out of a person's body and also because even small currents can kill. Do not attempt this experiment if you are not comfortable around electrical devices. I am not responsible for any harm you may cause yourself. I have done everything I can think of to make this safe, but don't come crying to me if you find yourself dead.

Now that I've started with this positive note, I can begin. I've split my web page into two sections. One for the impatient - who would like to make their own NOW. And the other for people who would like a little commentary from me. Oh, and those of you who just want to see the final product and don't care about the details, just skip to the Results. Happy reading!

Quick Details on building your own ECG

In Depth Information about my ECG

Introduction - What is an ECG? History behind it. What was I thinking?!

Some Stuff Sought Out - Miscellaneous things that I needed but didn't have

Adventures in Analog Land - The primary amplification circuit - all good ol' analog

Plenty of Programming - The visual basic source

Results - Maybe it's not perfect, but I think it's COOL!

Future thoughts - I still think I'm perfect, but I'm ready to argue these specifics

Notes - I didn't make this all up. Here's proof!

Not bad for about two weeks of work, eh? If any of you have any comments, questions, insults, etc; please email me. Thanks for coming.

Do you really think that a turbine could extract more kinetic energy from wind than 2344 times its land area of forest extracts with friction? Remember, modern turbines have three rather thin blades, whereas forests are by definition filled with foiliage. In terms of surface area against the wind, a single tree within the same area that a turbine takes would have thousands if not millions of times the area. Also, trees aren't very rigid against moderate windspeeds, converting wind into waste heat much more than solid objects do.

Plus, the amount of heat that atmospheric carbon dioxide causes to be forced into the atmosphere will more than make up for 16,000 TWh of turbine extraction. (0.3 watts per square meter yeilds more than 150,000 TWh over the earth's illuminated surface area.)

The size of a dollar bill is 6.6294 cm wide, by 15.5956 cm long, and 0.010922 cm in thickness.

A stack of one dollar bills worth $97.8 trillion would be 10 billion meters high or slightly more than 25 stacks of bills that each would reach to the moon.

Laid end-to-end the bills would stretch 15.25 trillion meters. That's long enough to stretch from the sun to pluto almost three times over.

That many dollar bills would cover the entire 68 square miles of the District of Columbia in a pile of bills two feet deep.

Oh, wait. Now I get it.

Michael.

Do you have any idea how big & massive the moon is? Do you really? Do you have any idea how much mass even one-billionth of the moon's mass represents? I don't think so.

The moon has a mass of approximately 7.4*10^22 kg.

That's 74 QUINTILLION tons.

If we mine the bloody thing, the amount of mass that we could ever remove is negligible compared to the mass of the moon. It simply doesn't matter.

Even though it doesn't matter, let's assume that the matter removed from the moon is then transported to earth...

In this scenario, the earth's mass has increased incrementally, meaning that the earth's gravitational attraction to the moon has increased as well. Therefore, the total mass of the earth-moon system is constant. The earth's attraction to the moon goes up as much as the moon's attaction to the earth goes down. Net effect on the earth-moon system is zero.

My brain performs more than 330 trillion ops/sec (stuff like image analysis, speech recognition, "AI",...)

The human brain has between 10 billion and 100 billion neurons. They can fire up to 100 times per second. 100 billion * 100/second is only 10 trillion per second.

So we must assume that either:

1. you have an enormous brain (3.3 trillion neurons would weigh about 50kg), or

2. that they fire very quickly, (you overclocked your brain and run around with a heatsinking hat and have to eat 20x a day) or

3. that you do some 'thinking' without using neurons.

Hmm, that last option seems to be the most reasonable. How's that working out for you, anyway?

Did you miss out this post and all the replies?

I saw the lame post.


Here's another picture and rather dry article. See, it's a radiation burn. How would you feel if that happened in your neighborhood? Sometimes, it's them or us and I'll choose us.

War is not something to be entered frivolously, but when a confirmed enemy demonstrates a willingness to develop the technology of mass destruction, and an eagerness to use it against us, it is wise to consider our own defense.

Last time i checked, police departments should not be broadcasting in the military spectrum.. second, houses don't tend to speed, so there's no reason why the police should beam their radar guns at your house. Third, even if they did, it wouldn't do anything.

Information on police radar guns: "The granddaddy of systems is X band radar... X band operates on the narrow channel from 10.500 to 10.550 gigahertz (GHz)... K band appeared in the seventies and quickly became popular in its deadliest form: a hand held gun featuring an instant on switch. K band operates on a higher-frequency channel from 24.050 to 24.250 GHz... In 1989, photo radar appeared on the scene, and it was bad news for motorists--it operated on a frequency that was undetectable by existing radar detectors. The FCC set up a channel for photo-radar from 34.200 to 34.400 GHz, which lies within the wide Ka band... Which brings us to the Stalker, the latest wrinkle in hand-held radar guns. It operates on the Ka band anywhere from 34.200 to 35.200 GHz."

Here is another informative article on how the Wi-Fi is colliding with the millitary radar, down at 5 GHz side of the spectrum, specifically 5.150-5.350 GHz.

Thus, police radar should never affect Wi-Fi, and vice versa.

I don't raise this issue to suggest any such event occurred with the Columbia disaster, but to provide some additional insight into the performance envelope of current technology.

As an additional note, he also said that the first generation of air-to-air radar systems on jet fighters could detect objects in orbit around the planet. He went on to say that subsequent revisions implemented system to block detection of objects above a certain, unspecified, altitude. If you think about it, this makes sense, as there is no magical barrier at the edge of the atmosphere blocking radar-wavelength electromagnetic signals. The ionosphere aproximately 250 miles above the Earth; the space shuttle flies between 200 to 240 miles above the Earth.

It isn't an 18 meter telescope. It is actually an array of four 8-meter telescopes. With three 1.8-meter telescopes for interferometry, and a 2.5-meter auxillary telescope. All of this should provide for relatively wide-field optical imaging.

Here is a great diagram and description of the VLT

As for being able to see the lander, it should be able to see objects of about 1.3 meters in diameter.
The supporting math:
(5e-5 m) / (1.6e4 m) * (3.85e8 m) = (1.2m)

Human hair: ~5 x 10^-5 meters
Maximim Distance human hair can be seen by telescope: 1.6 x 10^4m (according to story)
Distance to moon: 3.85 x 10^7m

Since the earth a land surface of roughly 148,300,000 sq kilometers and the current human population ow the world in about 6,228,394,430equals about .02381 square kilometers or 0.009193041 Square Miles = 256287 Square Feet per person.

70kg of empty calories and 1400cc of atmosphere.

Uhh, I call foul to your claims.

I call foul on your figures first. Emission levels are here. The carbon emissions for a modern coal-fired plant are 263gC/kWh. You are claiming 920gC/kWh. To compare, an oil-fired plant is 213gC/kWh and a gas-fired plant is 113gC/kWh! This is one THIRD of the Mazda 626's 350gC/kWh. I expect there's a mistake in your calculations.

But the problems in your argument aren't over. You're comparing coal-fired power plants against an oil-fueled 626! Coal is a poor alternative to oil. Energy densities here. Coal is at best 31MJ/kg. Oil is at worst 41MJ/kg. Gasoline in your 626 is 45MJ/kg. These energy densities influence CO2 emissions. To use a tired cliche, you're comparing apples and oranges.

Also I call foul with your conclusion. You only compared CO2 emissions per kWh and then concluded that the EV1 has better mileage!? If you want to compare mileage then you need to use the same fuels in the two cars and the plant and concentrate on the miles travelled!

But let's do some napkin calculations to get a feeling for "mileage". The electrical transport cost of overhead powerlines is less than 10%. Motors are 95% efficient. The best gas-fired plants are now exceeding 50% efficiency. So the fuel->wheel efficiency is 43%. Even the most efficient diesel generators as used on hybrids are less than 40% efficient. Cars range between 25% and 35% with petrol. So the plants use fuel more efficiently and therefore have the better "mileage".

We can also do some napkin calculations for cost. Cost calculator here. A car will typically cost 3x more per kWh than the plant. This is because plants get huge economies of scale and use much cheaper fuels. Cost alone proves nothing but combined with my previous arguments it proves that purely electric vehicles - not hybrids - are the best choice.

Do you know how much energy it takes to make a solar panel?

I'm afraid I don't know, though I'd be surprised if a single 100W solar panel exceeded the 3.65 Megawatt-Hours it can generate over the course of its service life.

They are energy carriers, because it takes more energy to produce them than you get from burning them.

I'd also like to note that, with the same calculation, a theoretical 100% efficiency solar panel of 8m^2 (or about 9'x9') could power a large house with air conditioning and have room to spare. (alternative energy advocates frequently point to how great their house is because it uses so little energy, but they also fail to mention that air conditioning is the first thing to go since it is such an energy hog. I prefer to compare to the current average homeowner's situation, for a more realistic picture) That's calculated as 1.0kW*5H*30days*8m^2=1200kWH/month assuming only 5 hours/day since a fixed solar panel isn't always exposing a 100% cross section to the sun.

If you pull up a Lucent/Avaya/ORiNOCO wavelan card control panel under windows, you will find there's a "Microwave Oven Robustness" setting which is designed to help make these work in the presence of a microwave oven.

From hypertextbook.com

potassium-argon dating
Potassium-argon dating is used to determine the age of igneous rocks based on the ratio of an unstable isotope of potassium to that of argon. Potassium is a comon element found in many minerals. The isotopic distribution of potassium on the earth is approximately 93% 39K and 7% 41K. Since these values are only approximate, the total percent abundance of these two isotopes is not 100%, but 99.9883%. The remaining 0.0117% is 40K -- an unstable isotope with a half life of 1.26 x 10^9 years. 40K has three decay modes: beta decay, positron emission, and electron capture.

1.26*10^9 = 1.26 BILLION. On a logarithmic basis, the article is much closer than you.

Yes I did read your original post, and your sources ;)

For what it's worth, somebody has bothered to do the calculations for us here, and they seem to set the record straight.

"According to Captain Kittinger's 1960 report in National Geographic, he was in free fall from 102,800 to 96,000 feet and then experienced no noticeable change in acceleration for an additional 6,000 feet despite having deployed his stabilization chute. This gave him an unprecedented 3900 m (12,800 feet) over which to accelerate. At such extreme altitudes the acceleration due to gravity is not the standard 9.81 m/s2, but the slightly lower value of 9.72 m/s2. Using these numbers, it is possible to calculate the maximum theoretical velocity experienced during this record-setting jump. The result is amazingly close to the value recorded in National Geographic.
...
"Given this, why then do so many sources report that Kittinger exceeded the speed of sound? One possible answer comes from the relatively obvious similarity between Kittinger's self-reported value of 614 mph and the most frequently misreported value of 714 mph (319 m/s). Somebody must have heard 614 but entered 714 accidentally into some officious document (like an encyclopedia). Some other people read the error and then reported it as fact. Many more people read these "facts" and suddenly nearly everyone was remembering the day Captain Kittinger broke the sound barrier. Another factoid is born.
....
"Captain Kittinger most likely did not exceed the speed of sound on 16 August 1960. To do so would have required an additional 1,300 m (4,200 feet) of free fall. That's a pretty large distance. I think he would have noticed it. This in no way detracts from his truly amazing accomplishment."

IANARS, but this makes sense to me.

-Kraft
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