Computers Learning to Tell if You're Happy or Sad; Audio Spotlight Sends Sounds Where They Need to Go
ANN KELLAN, HOST: Computers are learning to tell if you're happy or sad, an audio spotlight sends sounds exactly where they need to go, and pictures from space spotlight urban sprawl. Those stories and more are just ahead on SCIENCE & TECHNOLOGY WEEK. Hello and welcome. I'm Ann Kellan. It's a noisy world out there, and many of the sounds that hit your ears are things you really don't need to hear. A new invention may offer some peace and quiet.</s>UNIDENTIFIED FEMALE: Please refrain from smoking.</s>UNIDENTIFIED MALE: They are waiting to try and get across the runway.</s>KELLAN (voice-over): All that noise, loudspeakers blaring messages. What if you could target those announcements to only those who need to hear it? Joseph Pompei, a Phd candidate at MIT, says he has a solution for sound run amok.</s>JOSEPH POMPEI, RESEARCHER, MIT: When it's aimed right at the camera, you'll hear the sound very clearly, but when it's not, you won't hear much at all. We call this the audio spotlight, and what it does, is it makes a narrow beam of sound that behaves much like a beam of light. So if I shine it at an individual in a crowd, they'll hear it, but the people nearby won't.</s>KELLAN: And the beam can travel the length of about two football fields. We did our own test. From three flights away, Pompei aims the speaker at me. When I can hear sound coming from it and when I can't is a difference of a couple of steps. (on camera): OK, right here, I can hear the violin playing. But let's take more steps over here. I can't hear a thing. (voice-over): How it works: Music from a CD player is sent via cable to a special box, where the music's soundwaves are converted into a high-frequency, narrow ultrasound beam that humans can't hear. Pompei uses that long beam as a speaker, shooting the sound back into the air. Mixing with the airwaves, the signal naturally converts back to sound waves we can hear. But because it's now coming from such a narrow beam, the sound is more focused as well. (on camera): So the air is making the sound.</s>POMPEI: The air makes the sound.</s>KELLAN (voice-over): It's high-quality sound, with obvious applications.</s>UNIDENTIFIED MALE: Touch a color you want to paint.</s>KELLAN: Imagine listening to a tutorial about a painting at a museum with sound from the kiosk directed specifically at you. No more wearing headsets or disturbing others, or listening to a concert with the sound of each instrument spotlighted to different areas of the arena. He hopes in the next two years, companies will use his sound beam technologies to cut down noise, especially in public places.</s>KELLAN: If you're shaking your head over the high price of gasoline lately, you may be interested in a new experimental car unveiled this past week. It's called the Dodge ESX-3, and its maker, DaimlerChrysler, estimates it could get 72 miles per gallon. Its a hybrid that combines an electric motor and a three-cylinder diesel engine. The electric motor recaptures braking energy and runs the accessories. The ESX-3 seats five people, and the company estimates its sticker price would be around $30,000. Here's another approach to fuel economy: pond scum. Scientists have found a way to make green algae produce hydrogen fuel cheaply and easily. Normally, the algae act like most other plants, living on water, sunlight, and carbon dioxide, and giving off oxygen as a waste product. But when they're grown without air, green algae produced hydrogen. And when hydrogen is burned as a fuel, it leaves only water, no pollution. The researchers say, over millions of years, the algae somehow developed this alternative way to survive in conditions that would kill other plants. Later in the show, take a stroll through distant galaxies in the middle of New York. And when we come back, do you want a computer that looks over your shoulder and feels your pain? New dimensions in user friendly, when we come back.