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HTMLized, Coralized Piquepaille Content by Anonymous Coward · 2005-12-06 01:52 · Score: 0 · on Robots With Square Wheels?

Will the money you paid to get posted be worth it if no one visits your site?

Before starting our long working week, let's relax with this story of a bicycle with square wheels. No, it's not a joke. And it even rides smoothly. But there is a trick: the road must have a specific shape. The Math Trek section of Science News Online tells us more about this strange bicycle -- actually a tricycle with one front wheel and two back wheels.

Stan Wagon (Piquepaille's link was bad), a mathematician at Macalester College in St. Paul, Minn., has a bicycle with square wheels. It's a weird contraption, but he can ride it perfectly smoothly. His secret is the shape of the road over which the wheels roll.

Here is Stan Wagon riding his tricycle (Credit: Stan Wagon).

http://radio.weblogs.com.nyud.net:8090/0105910/ima ges/square_wheels.jpg

A square wheel can roll smoothly, keeping the axle moving in a straight line and at a constant velocity, if it travels over evenly spaced bumps of just the right shape. This special shape is called an inverted catenary.

A catenary is the curve describing a rope or chain hanging loosely between two supports. At first glance, it looks like a parabola. In fact, it corresponds to the graph of a function called the hyperbolic cosine. Turning the curve upside down gives you an inverted catenary -- just like each bump of Wagon's road.

In fact, the idea is not new, and Wagon picked it after seeing an exhibit about square wheels at the Exploratorium in San Francisco. But Wagon went further by exploring the relationship between all kinds of wheels and road shapes.

Just as a square rides smoothly across a roadbed of linked inverted catenaries, other regular polygons, including pentagons and hexagons, also ride smoothly over curves made up of appropriately selected pieces of inverted catenaries. As the number of a polygon's sides increases, these catenary segments get shorter and flatter. Ultimately, for an infinite number of sides (in effect, a circle), the curve becomes a straight, horizontal line.

Here is the conclusion of the article.

So far, no one has found a road-and wheel combination in which the road has the same shape as the wheel. That's an intriguing challenge for mathematicians.

So why don't you try to solve this math puzzle?

HTMLized, Coralized Piquepaille Content by Anonymous Coward · 2005-12-06 01:52 · Score: 0 · on Robots With Square Wheels?

Will the money you paid to get posted be worth it if no one visits your site?

Before starting our long working week, let's relax with this story of a bicycle with square wheels. No, it's not a joke. And it even rides smoothly. But there is a trick: the road must have a specific shape. The Math Trek section of Science News Online tells us more about this strange bicycle -- actually a tricycle with one front wheel and two back wheels.

Stan Wagon (Piquepaille's link was bad), a mathematician at Macalester College in St. Paul, Minn., has a bicycle with square wheels. It's a weird contraption, but he can ride it perfectly smoothly. His secret is the shape of the road over which the wheels roll.

Here is Stan Wagon riding his tricycle (Credit: Stan Wagon).

http://radio.weblogs.com.nyud.net:8090/0105910/ima ges/square_wheels.jpg

A square wheel can roll smoothly, keeping the axle moving in a straight line and at a constant velocity, if it travels over evenly spaced bumps of just the right shape. This special shape is called an inverted catenary.

A catenary is the curve describing a rope or chain hanging loosely between two supports. At first glance, it looks like a parabola. In fact, it corresponds to the graph of a function called the hyperbolic cosine. Turning the curve upside down gives you an inverted catenary -- just like each bump of Wagon's road.

In fact, the idea is not new, and Wagon picked it after seeing an exhibit about square wheels at the Exploratorium in San Francisco. But Wagon went further by exploring the relationship between all kinds of wheels and road shapes.

Just as a square rides smoothly across a roadbed of linked inverted catenaries, other regular polygons, including pentagons and hexagons, also ride smoothly over curves made up of appropriately selected pieces of inverted catenaries. As the number of a polygon's sides increases, these catenary segments get shorter and flatter. Ultimately, for an infinite number of sides (in effect, a circle), the curve becomes a straight, horizontal line.

Here is the conclusion of the article.

So far, no one has found a road-and wheel combination in which the road has the same shape as the wheel. That's an intriguing challenge for mathematicians.

So why don't you try to solve this math puzzle?

HTMLized, Coralized Piquepaille Content by Anonymous Coward · 2005-12-06 01:52 · Score: 0 · on Robots With Square Wheels?

Will the money you paid to get posted be worth it if no one visits your site?

Before starting our long working week, let's relax with this story of a bicycle with square wheels. No, it's not a joke. And it even rides smoothly. But there is a trick: the road must have a specific shape. The Math Trek section of Science News Online tells us more about this strange bicycle -- actually a tricycle with one front wheel and two back wheels.

Stan Wagon (Piquepaille's link was bad), a mathematician at Macalester College in St. Paul, Minn., has a bicycle with square wheels. It's a weird contraption, but he can ride it perfectly smoothly. His secret is the shape of the road over which the wheels roll.

Here is Stan Wagon riding his tricycle (Credit: Stan Wagon).

http://radio.weblogs.com.nyud.net:8090/0105910/ima ges/square_wheels.jpg

A square wheel can roll smoothly, keeping the axle moving in a straight line and at a constant velocity, if it travels over evenly spaced bumps of just the right shape. This special shape is called an inverted catenary.

A catenary is the curve describing a rope or chain hanging loosely between two supports. At first glance, it looks like a parabola. In fact, it corresponds to the graph of a function called the hyperbolic cosine. Turning the curve upside down gives you an inverted catenary -- just like each bump of Wagon's road.

In fact, the idea is not new, and Wagon picked it after seeing an exhibit about square wheels at the Exploratorium in San Francisco. But Wagon went further by exploring the relationship between all kinds of wheels and road shapes.

Just as a square rides smoothly across a roadbed of linked inverted catenaries, other regular polygons, including pentagons and hexagons, also ride smoothly over curves made up of appropriately selected pieces of inverted catenaries. As the number of a polygon's sides increases, these catenary segments get shorter and flatter. Ultimately, for an infinite number of sides (in effect, a circle), the curve becomes a straight, horizontal line.

Here is the conclusion of the article.

So far, no one has found a road-and wheel combination in which the road has the same shape as the wheel. That's an intriguing challenge for mathematicians.

So why don't you try to solve this math puzzle?

HTMLized, Coralized Piquepaille Content by Anonymous Coward · 2005-12-06 01:52 · Score: 0 · on Robots With Square Wheels?

Will the money you paid to get posted be worth it if no one visits your site?

Before starting our long working week, let's relax with this story of a bicycle with square wheels. No, it's not a joke. And it even rides smoothly. But there is a trick: the road must have a specific shape. The Math Trek section of Science News Online tells us more about this strange bicycle -- actually a tricycle with one front wheel and two back wheels.

Stan Wagon (Piquepaille's link was bad), a mathematician at Macalester College in St. Paul, Minn., has a bicycle with square wheels. It's a weird contraption, but he can ride it perfectly smoothly. His secret is the shape of the road over which the wheels roll.

Here is Stan Wagon riding his tricycle (Credit: Stan Wagon).

http://radio.weblogs.com.nyud.net:8090/0105910/ima ges/square_wheels.jpg

A square wheel can roll smoothly, keeping the axle moving in a straight line and at a constant velocity, if it travels over evenly spaced bumps of just the right shape. This special shape is called an inverted catenary.

A catenary is the curve describing a rope or chain hanging loosely between two supports. At first glance, it looks like a parabola. In fact, it corresponds to the graph of a function called the hyperbolic cosine. Turning the curve upside down gives you an inverted catenary -- just like each bump of Wagon's road.

In fact, the idea is not new, and Wagon picked it after seeing an exhibit about square wheels at the Exploratorium in San Francisco. But Wagon went further by exploring the relationship between all kinds of wheels and road shapes.

Just as a square rides smoothly across a roadbed of linked inverted catenaries, other regular polygons, including pentagons and hexagons, also ride smoothly over curves made up of appropriately selected pieces of inverted catenaries. As the number of a polygon's sides increases, these catenary segments get shorter and flatter. Ultimately, for an infinite number of sides (in effect, a circle), the curve becomes a straight, horizontal line.

Here is the conclusion of the article.

So far, no one has found a road-and wheel combination in which the road has the same shape as the wheel. That's an intriguing challenge for mathematicians.

So why don't you try to solve this math puzzle?

Coral cache link to video by ThomasKregaard · 2005-12-05 23:13 · Score: 2, Interesting · on Robots With Square Wheels?

http://www.globalcomposites.net.nyud.net:8090/Rein venting%20the%20Wheel%201.mpg

Here's additional linkage by TubeSteak · 2005-12-05 09:56 · Score: 2, Informative · on Looking Directly at Extrasolar Planets

http://www.u.arizona.edu/~grovers/ovc.html

Optical Vortex Coronagraph Figures

Optics Letters Preprint (4.8 Mb)[pdf] --- To Appear 15 December (ol.osa.org)
This work first appeared in the Master Degree Thesis of Greg Foo:
OSC QC350.O77 Vol. 353, 2005.

Just Like The Linux Kernel Problem by jack_csk · 2005-12-05 05:38 · Score: 0, Redundant · on Searchable C/C++ DB surpasses 275 million lines

Find out how many profane words are there in the source code comments.

Coral Cache... by cbiltcliffe · 2005-12-05 04:39 · Score: 3, Interesting · on Antispyware Shootout

http://www.zdnet.com.au.nyud.net:8090/reviews/soft ware/security/soa/To_catch_a_spy_Eight_anti_spywar e_tools_reviewed/0,39023452,39225147,00.htm

Karma whore, I know.....

I don't know why the changeover to CSS didn't include a little modification to the story submission script that automatically updates all story links to use Coral Cache. It really wouldn't be that hard, especially considering all of /. seems to be written in Perl.

Re:Summary by ploss · 2005-12-05 04:19 · Score: 1 · on Antispyware Shootout

The Coral Cache still works:

http://www.zdnet.com.au.nyud.net:8090/reviews/soft ware/security/soa/To_catch_a_spy_Eight_anti_spywar e_tools_reviewed/0,39023452,39225147,00.htm

The article is 15 pages long, and seems to be comprehensive and informative, geared toward massive rollouts at an Enterprise level. That said, here's some more of a quick summary of each product since their servers are melting:

Applications they tested:

Computer Associates -- eTrust Pest Patrol Anti-Spyware Corporate Edition: 4 1/2 stars
Lavasoft -- Ad-Aware SE Enterprise 2005: 2 1/2 stars
McAfee VirusScan Enterprise + Anti-Spyware Module 8.0: 4 stars
Microsoft -- Windows Defender (AntiSpyware): 3 stars
PC Tools -- Spyware Doctor 3.2: 4 1/2 stars
Symantec -- Client Security 3.0: 4 1/2 stars
Trend Micro -- Anti-Spyware for SMB 3.0: 3 1/2 stars
Webroot -- Enterprise Server: 3 stars

As always, remember that choosing Linux may be the best antispyware decision you can make! :)

Not good enough by roman_mir · 2005-12-03 15:35 · Score: 4, Funny · on Eleksen Introduces Electro Fabric

Eleksen company executives said the washable fabric can also withstand extreme pressure; they've rolled a car over it without any ill effects - this is unacceptable! I am not going to buy any of these products until they can withstand being rolled over by a tank. And what is it with the primitive 8 bit processor? I imagine it doesn't even need a decent fan to cool down. I demand a dual core CPU so that it will keep me warm during those long and cold Canadian winter nights. Since the batteries for such a system would have to be carried in 2 suitcases, while using the CPU at full power, I imagine it might be a good idea to add a propeller-hat with a generator to the entire ensemble. But make the propeller blades bigger, so that noone will think that it is a stupid outfit and won't try to beat us up. :)

Santa Claus by ndogg · 2005-12-03 04:17 · Score: 2, Funny · on Forbes Fictional 15

His elves are on strike. Mr. Claus responded by saying, "I assure you that this year's quota will be reached." He would not respond to questions as to how this will be done.

(Since I'm fairly certain that my friend will kill me if he found out I /.ed his server, some mirrors: Coral Cache.)

Deja vu... the n00b by Spy+der+Mann · 2005-12-02 15:30 · Score: 1 · on RPGs In The 'Real World'

http://www.thenoobcomic.com.nyud.net:8090/daily/st rip002.html

Re:North East photo dealers are a scam... by Anonymous Coward · 2005-12-01 02:28 · Score: 0 · on Consumer Strikes Back at Crooked Online Retailer

I tried to get it cached but I am not complete sure if it caches images or if it was cached in time before dying.

http://donwiss.com.nyud.net:8090/pictures/Brooklyn Stores/

Linux, not open source by Spy+der+Mann · 2005-11-30 17:30 · Score: 1 · on Open Source Worse than Flying

His problem is with Linux fundies, then. But we can't compare the Mandriva color schemes with Bittorrent, PHP, or Apache.
And yes, Linux has been famous for its poor hardware support.

URLs for the REAL papers say lots more. by billstewart · 2005-11-30 15:39 · Score: 4, Informative · on Security Flaws Allow Wiretaps to be Evaded

The shorter HTML version mainly talks about attacks on the voice eavesdropping parts, while the Longer PDF paper for IEEE has even more technical detail and talks about attacks on dialed-number-recording Pen Registers and CallerID, which the Feds and Local Police are able to wiretap without the same level of court order that a voice wiretap requires. (I've done the NYUD-automatic-caching versions of the URLs, rather than the raw URL, to protect against Slashdotting.)

Basically, there's a fairly high proportion of the wiretapping gear that's actually deployed is vulnerable, in spite of what the police PR folks say, and it's much easier to hack the pen-register technology (though probably impossible to prevent the phone company from giving a direct billing database feed to the Feds, which you probably can't hack.)

URLs for the REAL papers say lots more. by billstewart · 2005-11-30 15:39 · Score: 4, Informative · on Security Flaws Allow Wiretaps to be Evaded

The shorter HTML version mainly talks about attacks on the voice eavesdropping parts, while the Longer PDF paper for IEEE has even more technical detail and talks about attacks on dialed-number-recording Pen Registers and CallerID, which the Feds and Local Police are able to wiretap without the same level of court order that a voice wiretap requires. (I've done the NYUD-automatic-caching versions of the URLs, rather than the raw URL, to protect against Slashdotting.)

Basically, there's a fairly high proportion of the wiretapping gear that's actually deployed is vulnerable, in spite of what the police PR folks say, and it's much easier to hack the pen-register technology (though probably impossible to prevent the phone company from giving a direct billing database feed to the Feds, which you probably can't hack.)

multi-client applications by Anonymous Coward · 2005-11-30 11:27 · Score: 1, Interesting · on What Makes a Good IM Client?

I think that in a day and age where many people use different protocols or applications, if you must talk to them all, get something that doesn't just do one.

I mostly switched programs when other people said "Oh man, try this, this rocks!" Or when everyone I knew and talked to were using it. One year everyone had ICQ. Then they stopped, mostly. Then they all had AIM. Then some had MSN, some had Yahoo. Now its a crapshoot, you never know what they'll have! So I gotta stay prepared.

True, you may lose some of the special features of each individual application. Maybe you lose voice chat, maybe you lose certain icons. But the convenience outweighs all that, imo. Why load up 3, 4, or more applications when you can just load up one.

If you go with a client like GAIM or Miranda, you also don't have to deal with ads, tickers, news, or any bloated feature that you could just care less about.

Miranda is my application of choice. Its windows based, and is very stable. And, like firefox, its greatly enhanced by a slew of extensions and plugins. I believe that's one of its greatest features.

You can add in extra smiley sets, extra protocols. Pretty much anything.
Its open source so you can muck around with it, if something's broke, and add to it yourself. And as its only based in windows and windows alone, its quite steady and stable (unlike gaim, which has had a tendency to crash, or atleast crash more often than miranda).

And Miranda works out of the box with everything out there, even Google/Jabber. No grabbing anything else. Its fairly often updated. And its got a small footprint. Its sleek, straightforward and has a nice interface.

http://miranda-im.org.nyud.net:8090/ [Miranda-IM.ORG]

w00t! by un1xl0ser · 2005-11-30 06:35 · Score: 1 · on Next Generation of MP3 Glasses

How long before we start seeing these on woot.com?

Blog
Podcast

w00t! by un1xl0ser · 2005-11-30 06:35 · Score: 1 · on Next Generation of MP3 Glasses

How long before we start seeing these on woot.com?

Blog
Podcast

w00t! by un1xl0ser · 2005-11-30 06:35 · Score: 1 · on Next Generation of MP3 Glasses

How long before we start seeing these on woot.com?

Blog
Podcast

Full results in PDF by millette · 2005-11-29 21:00 · Score: 2, Informative · on Desktop Linux Survey Results Published

Full results are here in PDF format (333 KiB), coral linked : http://www.osdl.org.nyud.net:8090/dtl/DTL_Survey_R eport_Nov2005.pdf