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There is a cool thermal acoustic refrigeration technique that employs hemholtz principals described in American Scientist a few moons ago. There is also a means of using a Hemholtz filter to create a kind of check valve (I have to look for that reference... if you need it ask) hence providing a "one-way" flow.

Next time, try reading the fucking thing.

Idiots. Asshats. The lot of you.

More about Brazil:

Psychologist Robert Levine of the University of California studied numerous large cities, and found Rio de Janeiro, Brazil, is the kindest large city in the world. The outcome of the research mentioned in the articles below is not surprising to anyone who has been there:

Below is my translation of this article on the BBC Brazil web site:
Rio de Janeiro tem o povo mais solcito do mundo, diz pesquisa
http://www.bbc.co.uk/portuguese/noticias/030618_ri odejaneiroro.shtml

Mr. Robert Levine is certainly correct that Rio is very friendly, but his study ignores other facts. People in Rio are often happy, often flirting and kissing on the streets, and they joke a lot.

The BBC article discusses research reported in New Scientist magazine:
The Kindness of Strangers
http://www.americanscientist.org/template/AssetDet ail/assetid/18814?fulltext=true

_______________________________

Translation of the BBC article:
_______________________________


Rio de Janeiro has the most helpful people in the world, research says.

June 18, 2003 - Published 21:46 GMT

Atmosphere influences behavior, study affirms.

In spite of the violence, Rio de Janeiro is the metropolis with the kindest people found by researchers who studied 23 of the largest cities on the planet.

[My note: The phrase "In spite of the violence" is due to drug violence. Rio's reputation for violence is also due to media hype and apparently rivalry between the citizens of Sao Paulo and Rio. In actuality, the violence in Rio is not worse than other large cities. As in apparently all cities, most of the violence is in the areas where poor people live.]

The ranking was the result of research by psychologist Robert Levine of the University of California. According to him, blind people always receive aid to cross the Carioca [culture of Rio] streets, and invariably there is somebody willing to return a pen that another person dropped on the ground.

The Cariocas were ahead of the residents of Copenhagen (7th place), Stockholm (12th), Rome (16th) and New York (22nd), that were found to be less helpful.

In New York, for instance, the researchers led by Levine found that in only 28% of the cases somebody offers to help a person who limps whose belongings fell to the ground.

Good Latins

In Bangkok, in Thailand, a blind man will only be helped to cross the street in 42% of the cases.

The city that had the worst behavior in the Good Samaritan's index was Kuala Lampur, in Malaysia, that received 23rd placement in the ranking.

The best cities in the study were the cities of Iberian origin.

The capital of Costa Rica, San Jos, was second. Madrid was sixth, Mexico City, ninth, and San Salvador, the tenth.

"In general, we found that the people in cities in which Portuguese and Spanish is spoken tend to be more helpful", Levine said in his study.

A quick google search gave this.

Here is an article about why base-e is the most "efficient" continuous base, and thus base-3 becomes the most "efficient" integer base. It also explains a bit (har har) about ternary logic.

Here's a link to what you're talking about:

Third Base

It's a good read, stuff I didn't know until I read your post and looked it up =)

~Berj

Actually, we use binary because we can't really build anything else (there are no positions between "on" and "off", thus we are essentially limited, at this point in time, to base-2 computers). Base-3 computers exist, but they are really binary at heart so it's pretty pointless.

As this article explains, the real difficulty was in fabricating trinary components. By the time the techniques were good enough, everyone had already bet the farm on binary. Knuth was also a fan of ternary, with values -1, 0 and 1.

Brian Hayes recently published an article tackling this issue. He include a graph showing the cost of disk space over time and discusses the impact of increasing storage space on media companies. I strongly recommend taking a look.

Dark Matter isn't the only explanation for Fritz Zwicky's 1993 observation.

MOND or Modified Newtonian Dynamics proposed by Moti Milgrom is I think better. If I were to bet on someone winning a future Nobel, Milgrom would be the person.

I'm driving the VLT as I type this...sentence was interrupted for a preset...I'm back now.

Anyway, I know a number of scientists that seriously consider the Newton's may not work at large scales. Nature recently rejected a paper from some rather prominent that seemed to confirm that gravity behaves differently at large scales. But, science is very reluctant to change its equations and publication will have to await more data.

Just remember - Dark matter may not exist. Be skeptical of those who treat it as fact.

MOND FAQ

Dark-Matter Heretic [This is a wonderful article]

Tha American Scientist article claims that the event that first popularized the term "spam" was the simultaneous posting by the Phoenix law firm of Canter & Siegel to 6,000 Usenet news groups of a message with the subject heading "Green Card Lottery - Final One?" (in April 1994). But Brad Templeton has a VERY different story if he is saying here that spam will be 25 years old next Saturday - not nine. ("The earliest documented junk e-mailing I've uncovered was sent May 3, 1978 -- 25 years ago this Saturday.") This thread confirms, mind you, that the first time a USENET posting got *named* a "spam" happened on March 31, 1993 - so ten years ago last month is maybe right aFTER AL;L

Ah, very good. I did actually realize that there are scientists who think there is more to evolution than the modern synthesis includes. There are plenty. There are few if any who believe in a young earth.

James Valentine is apparently one of the discoverers of HOX genes. He seems to have an idea called the "Cell-Type Hypothesis" which I can't find any information about. Not a creationist.

Google could find nothing about Stanley Awamril. But Stanley Awamrik is a researcher on the early history of life on earth. Not a creationist.

Philip Signor I found less about, but judging by this book he's not a creationist.

Peter Sadler published a paper with this incomprehensible abstract. References here and here (PDF) indicate that he is (drum roll) not a creationist.

I didn't research further. Really, is this the best you can come up with?

Actually Werner Heisenberg got the calculation of the critical mass of Uranium 235 needed for a bomb wrong, which was the main reason that the Germans never commited any serious resources to a nuclear weapons project. Heisenberg calculated the critical mass to be of the order of several tons and it was therefore concluded that a bomb was not feasible. See this description of Heisenberg's reaction to news of the dropping Hiroshima bomb to see that he really believe that many tons of Uranium 235 was needed.

The first reasonably accurate calculation of the critical mass of Uranium 235 was made by Otto Frisch and Rudolf Peierls at the University of Birmingham, England in 1940. They found that only about a kilogram or so would be needed for a bomb and a memorandum submitted by them to British science advisor Henry Tizard on March 19th can be seen as the main trigger for the Manhatten project. Frisch and Peierls calculation turned out to be slightly low and in fact a few kilograms rather than one was needed but it was still three orders of magnitude less that the few tons the Germans thought was necessary.

Has anyone else noticed that Scientific American has suffered some serious Omni-fication in the past couple of years?

Yeah....it's gotten worse, but not quite bad enough to be called sensationalist crap like Omni. But it's certainly awful enough to have made me switch to American Scientist. The Sigma Xi publication delivers some kick-ass articles on all facets of scientific research, focusing mainly (in my view) on physics, math, and meta-research on scientific methods with some astronomy and life sciences thrown in. Lots of CS, too. Comes highly recommended despite its US-centric name.

1(-1)101

Here, basically the German's had abandoned the idea of a "nuclear bomb" because they belived that the amount of uranium required for a critical mass would require something on the order of a giant barge to deliver, making it impractical as a weapon. Here is information on Hiesenberg's reaction to hearing of the Allied nuke.

Here, basically the German's had abandoned the idea of a "nuclear bomb" because they belived that the amount of uranium required for a critical mass would require something on the order of a giant barge to deliver, making it impractical as a weapon. Here is information on Hiesenberg's reaction to hearing of the Allied nuke.

Not strictly true. The Nazis had a significant nuclear-weapons research program, using the intellectual powers of such notable physicists as Werner Heisenberg (of "Uncertainty Principle" fame). However, they were convinced that an exploding nuclear bomb was impractical, because Dr. Heisenberg had grossly mis-estimated the critical mass of uranium. Because of this, the most likely form of Nazi nuclear weapon was a subcritcal reactor-bomb which would "detonate" through a mechanism more like the Chornobyl meltdown than a runaway complete fission reaction.

That said, the commando raids on the various plants supporting this reasearch definitely helped guarantee that Nazi Germany never attained nuclear weapons. We can be fairly grateful for that, I think.

actually, no. The most compact/efficient representation is to do it in ternary, since 3 is the closest to e, which is the most efficient base.
Here's the article. I read this in a slashdot article, but since slashdot's search sucks, I can't find it, but here's the article that was linked to.

...to mass produce antimatter, but my solution will not fit in this space.

Milliken guessed or decided beforehand what he wanted the electrostatic constant to be and kept fudging his results until he got the one he wanted.

This is an unduly harsh analysis of Millikan's result and publication. There is no evidence to indicate that Millikan had guessed what he wanted, and then chose to the data to fit that. I suggest that you check out an article in The American Scientist (available freely in a posting by David Goodstein (Caltech)).

To briefly summarize that American Scientist article, Millikan had very exacting standards for the data that he would publish. If the oil drops were too small, too much effected by Brownian motion, or affected by innaccuracy in Stoke's Law (which he documented completely), the results were not published. If the drops fell to quickly for accurate measurement, the results were not published. So a marking like "error high, will not use" probably meant that he could not be certain of the numbers that he recorded. Likewise, even drops that were labeled "the best one I ever had" were not published. Even if the results of all his observations were taken into account, and not just the observations he published, his end result would have not changed significantly.

In short, to say that Millikan "guessed the answer" is at the very least unfair. He chose data that he was confidant had been recorded in a reliable fashion. You might fault him for other things, but not for choosing an answer before hand and then picking experimental results to support that.

The case has been rather overstated. David Goodstein, a current professor of physics at Caltech, wrote an article on this subject (warning: PDF). The relevant portion starts on page 3 - in summary, the data points that were discarded were being used to verify a separate formula for Stokes' law. A more recent analysis of all the points, published and not, doesn't show a bias regarding the charge value.

Unrelated but perhaps relevant, Goodstein also has an article titled Conduct and Misconduct in Science online.

It's a problem in base-2 also. Base-5 wouldn't have the problem, though.

Base-3 for computers would solve the problem. Apparently, in the very early days of computing there was some interest in base-3, although it never took off.

You could represent base-3 with -1, 0, 1. This is called balanced ternary notation. Quantum computers may end up using that variant of base-3. (I wish I could find a better quantum computing link. One of my former coworkers was doing his PhD on this stuff, and it was really quite fascinating.)

The best currency denominations are ones based on powers of 3. See theres a trinary number system, that instead of having the values 0,1,2, it has the values -1,0,1. This is called balanced ternary. I know it sounds weird, but it works out. This number system accurately represents the way we pay for money: if we want to pay 3 dollars we can pay 5 and get 2 back.

So the best system is based on the denominations 1,3,9,27,81 etc. This is the most efficient system for doling out change to pay an exact amount.

Think of it this way. There is a riddle which goes like this: if you have a two pan balance and you want to weigh an object (integral weight) with the fewest number of counter weights, which counterweights would you need? There answer is 1,3,9,27, etc. If you want to measure 14, you put down a 27 on one side, and put down a 9, 3 and a 1 on the side with the object you're weighing.

So you only need one of each bill to pay *any* amount exactly. So let's say you want to pay 14 dollars. You give 27, and you get back a 9, 3, and a 1. This works for ALL values.

see American Scientist: Third Base

That's fair enough, you're right. I'm not actually stating that he's a crackpot, or that his book's junk. But I'm still naturally wary of something that seems not to have been subject to much of the usual process of scientific research.

What I'm getting at is that some people seem to think that writing for a decade in seclusion and apparently avoiding peer-review is in some sense a good thing. It makes for a good story, but maybe not good science.

I've read the concerns at the end of one review:

The main text of A New Kind of Science (850 pages) names no names at all; the only work attributed to a specific individual is Wolfram's. The notes at the end of the book (another 350 pages in smaller type) do mention names of people, but briefly, grudgingly and often dismissively. [...] The book has no bibliography; the only references listed are Wolfram's own publications.

I'm certainly not saying his book is junk: it could be a work of genius that happens to share some of the hallmarks of crackpot theories. I'd just be personally much happier if he'd written a work of genius that didn't ring those alarm bells.

Still, anything that gets people thinking and talking about science can't be all bad :-)

American Scientist had a really good article on this back in 1996.

Heisenberg had estimated that a ton of U-235 was needed to reach critical mass, which was, of course, a huge overestimate. This is the reasoning he gave in a conversation with Otto Hahn immediately after being surprised by the news of Hiroshima (the conversation was secretly taped by the Allies):

"If I have pure 235 each neutron will immediately beget two children and then there must be a chain reaction which goes very quickly. Then you can reckon as follows. One neutron always makes two others in pure 235. That is to say that in order to make 10^24 neutrons I need 80 reactions one after the other. Therefore I need 80 collisions and the mean free path is about 6 centimetres. In order to make 80 collisions, I must have a lump of a radius of about 54 centimetres and that would be about a ton."

Can you see the mistake in his logic?

And it's more efficient than base 10. For even greater efficiency though, we should use base 3.

It is possible to build labyrinths of internal directories that eventually become too deep to navigate via the mouse. The feeling of such spiral filing systems is of endless depth, requiring great effort to retrieve a piece of information.

Here we go again, the "too many clicks" theory of useability. Which might have some validity, if it's proponents would support the notion with scenarios that actually made sense.

Shallow directory trees are a terrible way for humans to navigate large amounts of information. This theory ignores the effort involved in scanning the correspondingly huge numbers of entries in each directory to find what you want. The American Scientist has a relevant article which relates to this very subject, which was previously discussed on Slashdot. Look for the bit about telephone menu systems, right after figure 2.

This is not to say that filesystem hiearchies should be strictly ternary, just that the reasoning these so called "useability experts" use to come to their conclusions is suspect, at best.

...it's a damn shame that he's largely unknown by the public, not unlike Tesla.

He'd invented numerous devices, 165 of them in fact, many revolving around television. RCA screwed him out of their value- Sarnoff, the CEO of RCA at that time, did everything he could to destroy Farnsworth in the courts.

Because of this, devices like the Fusor, perhaps the smallest working hot fusion device ever devised, went by the wayside until recently.

Fusor Links:

Fusor Patent at the USPTO
A 1999 article in American Scientist about the Fusor
Richard Hull's webpages

A 43 to 50 percent error rate seems to me to be an astonishly poor showing.