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Comment TRAFFIC "EXPERIMENTS" AND A CURE FOR WAVES & J (Score 2) 178

TRAFFIC "EXPERIMENTS" AND A CURE FOR WAVES & JAMS
1998 William Beaty Electrical Engineer

My first 'experiment': accidentally erasing waves!
Once upon a time, years ago, I was driving through a number of stop/go traffic waves on I-520 at rush hour in Seattle. I decided to try something. On a day when I immediately started hitting the usual "waves" of stopped cars, I decided to drive smoothly. Rather than repeatedly rushing ahead with everyone else, only to come to a halt, I decided to try to move at the average speed of the traffic. I let a huge gap open up ahead of me, and timed things so I was arriving at the next "stop-wave" just as the last red brakelights were turning off ahead of me. It certainly felt weird to have that huge empty space ahead of me, but I knew I was driving no slower than anyone else. Sometimes I hit it just right and never had to touch the brakes at all. Other times I was too fast or slow. There were many "waves" that evening, and this gave me many opportunities to improve my skill as I drove along.

    I kept this up for maybe half an hour while approaching the city. Finally I happened to glance at my rearview mirror. There was an interesting sight.
It was dusk, the headlights were on, and I was going down a long hill to the bridges. I had a view of miles of highway behind me. In the neighboring lane I could see maybe five of the traffic stop-waves. But in the lane behind me, for miles, TOTALLY UNIFORM DISTRIBUTION. I hadn't realized it, but by driving at the average speed of the traffic around me, my car had been "eating" the traffic waves. Everyone ahead of me was caught in the stop/go cycle, while everyone behind me was forced to go at a nice smooth 35MPH or so. My single tiny car had erased miles and miles of stop-and-go traffic. Just one single "lubricant atom" had a profound effect on the turbulent particle flow within the entire miles of "tube."

http://amasci.com/amateur/traffic/trafexp.html

http://www.google.com/search?q=traffic+site:amasci.com

Comment Some sort of coprocessor (Score 1) 211

128 processors on a dimm............... Not every program is suitable for parellel execution.
http://en.wikipedia.org/wiki/Amdahl_law

So this might only be useful for task that can be parallelized. Then it will be a parallel coprocessor.

This might be exactly suitable to speed up things like the integer fractal program fractint, but what else can benefit?

Comment No life? (Score 1) 286

an "astrobiology finding that will impact the search for evidence of extraterrestrial life."...............

Maybe they found there is NO life at planets where possible signs of life where seen.

Comment Autism (Score 1) 129

This brain mapping would be great if they mapped an autistic brain and compared it to a 'normal' brain.

I want to know if there is a difference in 'architecture' between autistic and normal brains.
Software

Submission + - Five reasons why Linux hasn't made it big

Flames_o_War writes: An article on ZDNet examines the reasons behind why, after more than a decade, the Linux is still not making any serious inroads into the Windows/Mac market share:

The PC market is extremely cut-throat. It has to be because consumers will go to great lengths to save a few bucks when buying their latest system. But it seems that this thriftiness hasn't resulted in hordes of users choosing to buy PCs without Windows installed and instead choosing to install Linux instead. In fact, there are plenty of users who would rather break the law and install pirated copies of Windows than go the legal route and install a Linux distro. On the whole, most people would rather spend the money on Windows (or Mac) than take the time to experiment with Linux.

Why?


The article goes on to list five reasons:

1 — On the whole, users aren't all that dissatisfied with Windows
2 — Too many distros
3 — People want certainty that hardware and software will work
4 — As far as most people are concerned, the command line has gone the way of the dinosaur
5 — Linux is still too geeky


I'm a big Linux fan but after years of listening to the Linux fanboy community promise that the Linux big break is just around the corner, I'm starting to feel that the article is right, the demand for a non-Microsoft OS is not that big outside of geek circles.

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