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I've always wondered about bird vs. helicopter efficiency ... here's one guy's opinion.

http://mb-soft.com/public3/birdeff.html

If true, nature's "painfully inefficient reciprocating motion" leaves our "nice, efficient rotary motion" in the dust.

This seems ludicrous. I can't imagine a fleet of ships being able to harness enough energy with current power sources to affect a temperature change to billions of tons of ocean water whether by circulation or thermal exchange of some sort.

Disrupting the atmospheric currents of a tropical depression BEFORE it forms a cyclone seems much more manageable.

I believe there have been a few proposals for doing just this with supersonic aircraft orbiting the eye of potential or existing hurricanes. The coordinated positions of the shock waves on the eye wall would theoretically disrupt the rotation of the storm. Far less energy would be required to form an interference pattern in the rotation that to super heat or pump water from ocean depths.

A patent application filed by Prof. Arkadii Leonov and his colleagues: http://www.wipo.int/pctdb/en/wo.jsp?WO=2008094226 Another: http://mb-soft.com/public/hurrican.html

Of course, we've all seen this work with alien probes visiting trying to talk to whales.

Turn in your geek card if you haven't performed the proper energy in / energy out comparisons.

A 65g chocolate bar contains about 250 calories or about 1000kJ. To do 1000kJ of work you could lift a 10kg weight from waist height to head height about 12,000 times. If you did one rep every 2 seconds, that would take you five and a half hours.

Of course this is meaningless since your body isn't a 100% efficient machine and energy is lost both through the digestive process and the mechanical process of using muscles.

You can't neglect differences in the conversion efficiency of different people when performing these comparisons. One person could produce the same energy output but be able to eat many more calories as a result of different conversion efficiencies.

This has a bit more on the subject. http://www.mb-soft.com/public2/humaneff.html

why not harness the power of the gyroscope?!?!

/end sarcasm

really? you're thermodynamics teacher should be bludgeoned if someone sold you that out and out lie. Sure there are technologies like fuel cells that, in theory, can do that but most power plants run off of some internal combustion process, weather it be a steam plant or diesel generator, and that means that you're limited by the efficiency limiting that thermal cycle. For most forms that's the Carnot Cycle, which peaks out at 60% for most real world situations. This is why it was a big fricking deal when GE came out with a 60% efficient power plant which still kicks the crap out of the 37% theoretical limit for most steel IC engines.

I can see what you are trying to say, but, It seemed to a perfectly obvious method for Isaac Newton I feel much more at ease with AHA moments than a physicists maniacal blackboard ramblings. Like the old adage "if you can't explain something in three sentences, you haven't thought about it enough" Consider rutherford's slit experiment, Galileo's cannonball, Newton's prism or maybe Foucault's pendulum. Ducky isn't there yet, - Each of these seem a lot less abstract than a formula like this:? {g}=-{MG \r^2}\{r}}.

I was referring to the Protestant work ethic, which as the link notes, is sometimes just referred to as "the work ethic". Your mention of "discipline and accepting your fate" means you already have it. You've been thoroughly indoctrinated by your upbringing in a Western capitalist nation. ;) It apparently works well for a lot of people, which is why it's spread so widely - it has great survival value - but not everybody adapts to it so well.

You're also a republican, in a 19th century sense: "each man must somehow be persuaded to submerge his personal wants into the greater good of the whole" (attributed to Gordon Wood). If your personal wants are not to wake up early, but you've somehow been persuaded to do it anyway (money? belief in public virtue?), you're a good republican. That's a pretty noble thing, but I can't help feeling that it might be possible to arrange things to better take our biological differences into account. We're still living 19th century lives in many ways.

I think the idea is that this kind of system works in reverse during the winter, pulling that stored heat out of the ground and using it to heat the house. This way, you're taking advantage of the insulating properties of the ground more than its normally contstant temperature.

Here's a detailed description of the technique: http://mb-soft.com/solar/saving.html Once you have the basic concept down, it's basically just a matter of doing the math and figuring out the system dimensions, and then figuring out if you can build it for a reasonable cost vs a traditional system. I think it helps a lot if you're building a home from scratch rather than retro-fitting an existing home.

There are some explanations around that explain the "Deja Vu" phenomenon physiologically. (Those are only the first two I've got on Google, many others are avaliable, but mostly centered on the "separated routes" theory).

It was the cops radar gun, you'd have to question him, he said 70...

It was obviously a tree he clocked :-)

Umm, airplanes ARE able to fly because of the Bernoulli effect.

If the Bernoulli effect is what makes flight possible, then how can an airplane fly upside down? Wouldn't the Bernoulli effect push it into the ground? Or how can a wing with a symmetric airfoil, for example a simple balsa glider with a flat slab wing fly at all?

The answer is that reactive lift, caused by angle of attack, also makes flight possible. In practical airplanes, both forces play a part, but reactive lift is pretty much always the bigger contributor, up to 80% for heavy-lifting planes. Planes that rely exclusively on the Bernoulli effect are not economically practical.

There is a pretty good article here.

I have read the article and I found no explaination at all about how the clock can calculate the local time including the leap second. Ok, the clock have a synchronization of the earth rotation using the sunlight, but this in no way synchronized to the local time. First current local time is an offset of UTC and UTC is an offet to TAI and TAI is a averge of many atomic clocks, so the basic of our local time is not astronomic, but atomic (http://cr.yp.to/proto/utctai.html). This clock can be a impressive model of the astronomic motion, but this is the wrong way to tel the local time. Second, even for the astronomic motion I have doubts, since I never see a paper telling that the earth axis motion can be know for 10'000 year. But you can find papers that tel exactly the opposite: this motion is largely unpredictable as now for a such long time. See this URL about how complexe is the earth rotation axis http://mb-soft.com/public/precess.html and this URL about why this is impossible to predict at full precision this movement http://www.cv.nrao.edu/~rfisher/Ephemerides/earth_ rot.html. Did you know that such bulltins exists ftp://maia.usno.navy.mil/ser7/iersexp.sup ? Last, did you realiste that the local time is an human concept that have radicaly changed in less than one century ? How can someone assert that this will not change in 10'000 year ? Juste an exemple: the Asian earthquake end last year did have an observable impact on the earth roation, see http://www.nasa.gov/home/hqnews/2005/jan/HQ_05011_ earthquake.html. So keep in mind this basic facts: 1) astronomic motion is unpredictable in full precision for long time; 2) local time in based on atomic observation plus offset to keep it compatible with astronomic observation, not the opposit!

> "A newly discovered fragment of the oldest surviving copy of the New Testament indicates that,
> as far as the Antichrist goes, theologians, scholars, heavy metal groups, and television
> evangelists have got the wrong number. Instead of 666, it's actually the far less ominous 616."

Why not take a look at the source itself?, which states:
One feature of particular interest is the number that this papyrus assigns to the Beast: 616, rather than the usual 666. (665 is also found.) We knew that this variant existed: Irenaeus cites (and refutes) it.

Irenaeus was born in AD 130 - 2 centuries before this papyrus. The 616 was dismissed as error even back then. Irenaeus writes:

1. Such, then, being the state of the case, and this number being found in all the most approved and ancient copies [of the Apocalypse], and those men who saw John face to face bearing their testimony [to it]; while reason also leads us to conclude that the number of the name of the beast, [if reckoned] according to the Greek mode of calculation by the [value of] the letters contained in it, will amount to six hundred and sixty and six; that is, the number of tens shall be equal to that of the hundreds, and the number of hundreds equal to that of the units (for that number which [expresses] the digit six being adhered to throughout, indicates the recapitulations of that apostasy, taken in its full extent, which occurred at the beginning, during the intermediate periods, and which shall take place at the end), I do not know how it is that some have erred following the ordinary mode of speech, and have vitiated the middle number in the name, deducting the amount of fifty from it, so that instead of six decads they will have it that there is but one.

The number is 666 as Irenaeus testimony (itself based on those that knew John - the author of the Book of Revelation personally) and the vast majority of manuscripts attest. Perhaps the fact that this papyrus was found in an "ancient rubbish heap" means something.

Try this. Direct refrigeration from the sun - and it doesn't even use salt water and ammonia.

If you just want cooling (er, you can also get heating with this) and you have the property, it's even easier. Dig a buncha ditches and lay some pipe. You combine these inlets with a decent solar chimney and you have a completely "passive" (ie no machine moving parts, no electricity needed) means of circulating 60 degree air throughout the house.

Oh, and here's a DIY solar ice maker - just for the heck of it.

Feel free to message me about this. Solar energy is something of an avocation of mine.

Homes in snow areas accumulate snow on the roof. This actually helps insulate them in winter. And, even if it didn't, this means those expensive roofing panels are useless in winter until someone climbs on the roof to sweep away the snow.

You cannot "aim" shingles. If your house is "conventional" (as the building codes require in many areas) you are going to have a pitched roof with a peak. At any given time, half the area of the roof is going to be utterly wasted. And even with the sun directly overhead, one is not likely to experience "peak" generation.

That 10% efficiency is peak not average. So you might be able to get a third that - or ~3.5% efficiency - for a roof. A roof that costs ten times as much to install and five times as much to maintain when you get the semi-annual hail or wind damage.

I do think solar energy is where it's at, but I'm dismayed that solar cells seem to be the only solution the mainstream is willing to consider. The sun provides lots of energy and you DON'T have to convert it to electricity to make use of it. The earth itself also can provide huge sums of heating and cooling energy and yet, even in homes with basements, this utility source is rarely exploited in an efficient manner. Design a house properly and you need hardly pay for heating, hot water, or even for cooling in the summer. Much of this is possible without making use of a single solar cell, and without substantially adding to the maintenance costs of the building.

This article addresses a few more interesting things as well.