Archive for January, 2007

Houses that float

January 31st, 2007 by Gene
 

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Imagine if your house could float instead of being ruined by hurricane floodwaters. Engineers in Holland are doing more than dream about it. We’ll take a look, today on Engineering Works!

During 2005, hurricanes Katrina and Rita hammered coastal Louisiana, Mississippi and Texas with wind and floodwaters. The water ruined thousands of homes. It’ll take years to rebuild.

People in Holland live with the threat of this kind of flooding all the time. Not from hurricanes, but from big storms in the North Sea. More than a quarter of the country is below sea level. And it’s sinking a little every year. They depend on a huge system of dikes, pumps and canals to keep everything dry.

Dutch engineers and architects have come up with an idea they say should avoid a lot of the flood damage from hurricanes Katrina and Rita. Houses that float. Instead of being anchored in the ground, these houses have foundations that are waterproof, like boats. To keep the houses from floating away, they slide up and down on big steel columns, as much as 15 feet.

Right now, the houses are pretty expensive. About $350,000 for a 1,300 square-foot house. A lot of the extra cost goes to making connections for household utilities flexible. Only a few dozen houses have been built so far. The designers say that price should come down as more are built.

There’s no high water forecast around here, and that’s it for this time.

Photo from Ecoboot, a site about Dutch floating houses.

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Traffic Engineering

January 24th, 2007 by dstmartin
 

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Everybody complains about getting tied up in traffic. We’ll take a look at some unusual ways traffic engineers are helping traffic move faster, and safer — today, on Engineering Works!

We’ve had traffic engineers almost as long as we’ve had cars and traffic. Traffic engineers are civil engineers who specialize in keeping traffic on streets and highways flowing smoothly and safely — things like how wide you make the roadway, traffic lights, the speed limit, where you install signs, sidewalks and crosswalks to keep vehicles and pedestrians moving along.

We complain about traffic tie-ups, but traffic engineers’ plans usually work pretty well.

In one small town in Holland, traffic engineers cleaned up traffic at a dangerous intersection by doing the opposite of what you’d expect. They ripped out the traffic lights, road markings and some pedestrian crosswalks; then they put in a traffic circle. But they didn’t replace any of the signs – speed limit, who has the right of way; none of them.

Goofy, huh? But it worked. Traffic slides through that intersection more smoothly than when the lights and warning signs were there, and with fewer accidents. The idea may sound crazy, but it’s catching on, from Holland and Denmark to England and Palm Beach, Fla.

Fewer signs and traffic lights, less distance between cars and people on the sidewalk; people have to pay attention to what they’re doing. So they drive safer.

It’s time for us to drive on out of here. We’ll see you later.

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Water Tower

January 19th, 2007 by Gene
water
 

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When you turn on the faucet at your kitchen sink, water comes out. What makes it do that? We’ll find out. Today, on Engineering Works!

Running water is one of those things that are just – there. Nobody thinks too much about where the water comes from or how it gets to your sink. It’s more complicated than you think.

Running water has been around at least since the ancient Assyrians. They built a 900-foot-long aqueduct to carry water across a valley to the city of Nineveh. Getting it there was a real engineering challenge. Getting water to our houses these days involves a nice bit of engineering, too.

It usually starts with a water tower. If you grew up in a small town like we did, you could see the water tower from just about everywhere. The tank on top of the tower usually is designed to be at least 100 feet above the highest building that uses water. That 100 feet is what gives you the pressure that pushes the water out of your faucets.

Water towers usually hold enough to supply the town for a day, plus a little. Pumps replace the water we use to shower or wash dishes, and they refill the tank during the night when we don’t use much water. It’s the water tower that keeps your faucet running steadily when you fill the sink.

Someone has turned off our faucet, so we’ll quit before we dry up. See you next time.

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Fly Eye

January 10th, 2007 by Gene
Fly Eye
 

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Engineers are working out a new way to help digital cameras see better. They’re getting some unlikely help. We’ll look — today, on Engineering Works!
It happens to everybody – we draw our trusty digital camera to take a picture of Aunt Sal during the family reunion. But she’s standing in front of a sunlit window. No matter what you do, it doesn’t work. Either Sal is so dark you can’t see her face, or the light from outside washes out everything else.
Engineers are using advanced computer techniques to get perfect pictures in conditions like this — with help from a fly.
Here’s how it works. When we look at a scene, our brain balances the brightness so we see detail pretty well. But the light meter in your digital still or video camera can only read how bright it is in specific places in the scene or average the light it sees.
Enter the fly. Flies’ eyes aren’t like ours. Instead of just one big eye, their eyes have hundreds of tiny ones. Each one sees different things, and the fly’s brain combines it all into one detailed image.
Engineers are borrowing this idea and applying it to the way digital cameras process still or video images. It gives detail over the whole image, regardless of contrasting light levels.
There’s a catch, naturally. The equipment is so expensive most people won’t be able to afford it.
Oh, well. Our scene is beginning to fade. See you next time.

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Windmills

January 3rd, 2007 by dstmartin
 

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Hold onto your hat. It’s time to get into the wind. We’re going to find out about wind power, today on Engineering Works!

Most of the time, when someone says wind power we think of windmills – the pretty ones in Holland, maybe; or on your grandfather’s ranch.

The first windmills were built about 500 A.D. in Persia, where they powered water pumps and ground grain into flour. By the 1300s, wind technology had found its way to Europe, still used for pumping and grinding.

At its most basic, wind technology is pretty simple. Stick something flat out where the wind blows on it and it moves. Engineers call the idea drag. If that something is a sail, it can move a boat. If it’s attached to a lever, it can turn an axle to run a pump or grinding mill.

Modern windmills use aerodynamic principles like lift to get more out of the wind, but the idea’s the same. Now, engineers are looking at ways to use high-tech wind generators to make electricity. Even that’s not new. The first windmills that generated electric power showed up in the United States more than 100 years ago.

Wind generators aren’t as efficient as coal- or oil-fired generators and it’ll take a whole lot of them to produce a useful amount of electricity. But we don’t have to worry about running out of wind.

It’s time for us to blow on out of here.

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