Some of the world's most gifted teenagers are gathering in Atlanta to participate in Intel's International Science and Engineering Fair. Their projects range from transmitting invisible data to extracting fuel from waste. Mike Cooper reports for VOA from the southeastern U.S. city of Atlanta.

Teenagers from around the world are presenting projects at the Intel International Science and Engineering Fair. The 50-year-old is the world's largest pre-college international science fair.

Students compete for more than $4 million in scholarships, trips, science equipment and cash awards.

Many of the students have competed in local or regional science fairs, and their work is being reviewed by more than 1,000 judges who have a doctorate degree or years of professional experience in nearly every scientific discipline.

Joel Knighton, from Coon Rapids, in the northern state of Minnesota, studied ways of embedding data in pictures to find which would be the least visible to the human eye.

He says his work could help provide secure data transmission through computers without anyone being aware the data are transmitted.

"As far as what they are looking for, they really look a lot more at the content of the project at this level. Once you have reached the point where your judges are really educated in the field, they will ask a lot of the harder questions."

While you would expect presentations to involve computer science, because the event is sponsored by Intel, the California-based manufacturer of computer chips, there are also presentations involving biology, earth science, energy, medicine, physics and astronomy. Forty-eight percent of the students competing are female.

Jennifer Vanderweele, from Portland, Oregon, studied ways to extract oil from algae grown in waste water to make biodiesel fuel for transportation. She had already experimented making fuel from waste vegetable oil from her school cafeteria.

"You need more than just the waste vegetable oil and currently a lot of the crops used are corn and soybean, oil from those, but those take a lot of space to grow and energy to grow and harvest. So algae seems like a better solution because it can grow in less space and take less energy," she said.

Michael Glawe of New Ulm, Minnesota, used an aquarium and handmade tools to simulate the effects of a tsunami generated by an earthquake. "I designed an earthquake model and I used it in a 7x3-foot (2x1-meter) tank and I was actually able to watch propagations and how waves actually move in wave physics. And I came up with a couple of theories as to how waves move," she said.

The executive director of the sponsoring Intel Foundation, Wendy Hawkins, says students from 51 countries are participating this year. She says India, China and western Europe are well-represented, but not all of the students have access to resources, money or equipment.

"It is often kids who are scrounging for parts and putting together things that truly are amazing - robotics and solving problems in terms of water quality, solving very real issues, health issues that affect the people that they live with in ways that are real and measurable with remarkably little resource," she said.

Many of the presentations have concrete applications. Yuan Ning, from Malaysia, was inspired to develop a computer-based system to help the deaf and mute people to communicate with others.

"I came across a scene when I saw a deaf-mute in the post office. He was trying to communicate with the officer there, using sign language. But the officer just could not get what he want[ed]," Yuan Ning said.

There are more than 1,200 projects being presented at this year's International Science and Engineering Fair. The researchers may only be teenagers, but almost 20 percent of them have applied for or received patents for their work.