A national engineering laboratory in Tianjin is the base of the world’s largest and most advanced sound source identification system for commercial use. At first sight, the equipment, known as a sound camera and consisting of a big wheel with a supporting frame, resembles a mini Ferris wheel that lacks seats and cannot turn around. A closer look at the 5-meter-diameter wheel reveals high-tech features like an array of 144 sensors used to capture, identify and analyze the source of noise on railways.“It is like a sound radar (雷达) for discovering noise,” said Hu Wenlin, vice head of the National Engineering Laboratory for Noise Control and Reduction at China Railway Design Corporation.

Hu said that the data produced by the machine allows engineers to better understand the sounds generated when a train passes by, e.g. which part produces the most noise. After analyzing the data, engineers can draw up precise plans to reduce noise and make construction plans accordingly. For example, if a railway passes a residential area with stricter noise abatement requirements, engineers can come up with a plan to minimize noise, usually at greater expense. But if a railway passes a place with more relaxed noise control requirements, designers can make a cheaper plan.

Noise control technologies have been applied to dozens of major railway projects across the country. The sound camera, fully developed in China, is advanced by world standards, said Wang Changjin, the director of the National Engineering Laboratory. Before the sound camera was available, engineers usually used a pole fitted with sensors to collect sound data along railway lines.“It cannot be compared to the technique we are using now, which is far more precise,” Wang said.

The machine is just one of many innovations developed by the laboratory. It has conducted many research projects on railways, leading to the development of key noise control equipment for high-speed railways and bringing quieter lives to people living near the lines.

Researchers say a new electrical device placed in three paralyzed patients has helped them walk again. The lower bodies of the three patients were left paralyzed after they suffered spinal(脊柱的)cord injuries. But a device implanted in the spinal cord was able to send electrical signals to the muscles to permit them to stand, walk and exercise.

Scientists have discovered that neurons—which receive and send signals for muscle movements—often still work in injured patients with serious spinal cord injuries. However, past research into spinal cord injuries has centered on the stimulation of neurons. Now in the latest experiment led by Gregoire Court in e and Jocelyne Bloch of the Swiss Federal Institute of Technology in Lausanne, three paralyzed men were implanted a new electrical device designed to copy an action of the brain, in which it sends signals to the spinal cord that result in muscle movement. When the spinal cord receives the brain signals, it stimulates a collection of nerve cells that can activate different muscles.

The researchers reported that all three patients who got the spinal cord implant were able to take their first steps within an hour after receiving them. Over the next six months, the patients regained the ability to take-part in more advanced walking activities, the study found. They were also able to ride bicycles and swim in community settings.

Unlike other attempts to help paralyzed patients walk by stimulating nerves through the back of the spine, Court in e said that his team redesigned the devices so signals would enter the spine from the sides. This method permits more direct targeting and activation of spinal cord areas, he said.

The team then developed artificial intelligence (AI) systems linked to the device. The AI controls electrodes on the device to send signals to stimulate individual nerves that control muscles needed for walking and other activities. However, because the patients’ muscles were weak from not being used, they needed help with supporting their weight the researchers said. It also took some time for them to learn to work with the technology. Still, Bloch said, “The more they train, the more they start lifting their muscles, the more fluid it becomes.”

People who have trouble walking or moving around often have a hard time enjoying the beach.Most beaches don't have ramps (坡道) or special walkways to allow disabled visitors to move around easily, or to get in and out of the sea safely. But hundreds of beaches in Greece now offer a new way for people in wheelchairs to get into the water by themselves. It's called Seatrac.

Seatrac is a system that was designed to solve this problem. Seatrac is basically a chair on a moving ramp that can smoothly carry a disabled person into the sea. Once in the sea, the person can either remain in the chair, enjoying the water, or go for a swim. The Seatrac system can help anyone who has a hard time walking,including older people and pregnant women.

The chair is operated by remote control. When the person is ready to get out of the water, the Seatrac system brings the chair back to the top of the ramp. It's even possible to take a shower in the Seatrac chair after going for a swim.

Seatrac was invented and developed by Mr. Fotiou, a professor and his partners at Greek university. They designed the system and in time, they formed a company called TOBEA to build and sell the systems. The company worked hard to make the system simple to put in place and easy to run.A wooden walkway allows wheelchair users to reach the Seatrac. The system is solar powered. It doesn't require outside power, and can continue to run even if the electricity goes out. The Seatrac system can easily be packed up and stored when swimming season ends.

This summer, the Seatrac system is being used at over 220 beaches in Greece, Cyprus, Italy,and Latvia. The Seatrac service in Greece is gratis to tourists. The Greek government has helped pay for it and hopes that Seatrac will help attract more tourists to the country.