Imagine a world where you move around in front of a personal computer in your own sound space. You listen to your favorite songs, play loud computer games or watch a movie--all without other people hearing the sound. That is the possibility presented by “sound beaming”, a new technology from Noveto Systems, an Israeli company.

On Friday, the company debuted(首次推出)a desktop device that sends sound directly to a listener without the need for headphones or a special receiver.

Noveto Systems gave The Associated Prees(AP)a chance to test its Soundbeamer 1.0 before its debut. The AP’s Louise Dixon writes that is listening to the device is like something from a science fiction movie. The sound seems so close that it feels like it is inside your ears while also in front of, above and behind them.

Noveto Systems expects the device will have many uses. Office workers could listen to music or conference calls without others hearing. People could play a game a movie or music without waking up others in the same room. Because the device does not use headphones, it is possible to hear other sounds in the room clearly.

The device uses a 3-D technology that finds and follows the ear position of the listener. It sends ultrasonic waves to create sound pockets by the user’s ears. Sound can be heard in stereo(立体声音响)or3-D. The3-D method creates sound on all sides of the listener, the company said. The demo(演示)version of the device includes nature videos of birds on a lake, bees flying and a quiet waterway.

While the idea of sound beaming is not new, Noveto Systems is the first to launch the technology. Its chief executive officer Christophe Ramstein said a “smaller” version of the device would be ready for release to consumers next year.

Mya Le Thai is a scientist studying at the University of California. She recently discovered a process that may result in batteries that last forever. Thai said she had been frustrated that the batteries for her wireless devices degrade(退化). Over time, they fail to charge fully. She decided to do something about that problem.

At first, she and her team thought about inventing a new battery. But as they experimented, Thai discovered something that might permit lithium-ion batteries(锂电池) to last forever. Lithium-ion batteries power most wireless devices. Over time, the batteries lose the ability to hold a charge. One of the reasons lithium-ion batteries degrade is their use of nanowires(纳米线) to carry electricity. Nanowires are extremely thin. Nanowires are extremely efficient carriers of electricity, which makes them useful in batteries. But Thai said their thinness also makes them weak. “Nanowires break over time,” she said. “That’s why they lose capacity.”

But, Thai had a theory: The nanowires might last longer if covered with a gel(凝胶). She and the team tested her theory. The team tried many coverings for the wires. PMMA was one of them. The PMMA coated nanowires showed no evidence of damage. The results suggest that batteries could last forever, without losing charging ability. Thai hopes to continue her research to understand why this gel works so well and to see if any other gel could create better results.

Mya Le Thai told VOA she is enjoying the publicity about her discovery. She said she never expected her research to get media coverage. “It’s kind of cool,” she said. “I’m really glad people are showing interest in my work and not just in the work itself, but also in technology and energy.”

Driverless cars used to be the sort of thing you’d see in sci-fi films, but in 2020 they’re becoming a reality. Autonomous car technology is already being developed by the likes of Lexus, BMW and Mercedes, and we’ve even tested Tesla’s driverless Autopilot system on UK roads. Across the Atlantic, Google is developing its automated technology in the wild, and Apple is rumoured to be working with BMW on its own-probably automated-car.

Fully-driverless tech is still at an advanced testing stage, but partially automated technology has been around for the last few years. Executive saloons like the BMW 7 Series feature automated parking, and can even be controlled remotely.

With so much investment and interest in driverless technology, it’s easy to assume that self-operating cars are likely to happen soon, but they’re much further away than we might think. Before driverless vehicles go to market widely, manufacturers must deal with a range of technical and ethical challenges, and prevent the biggest threat to autonomous technology: humans.

The human problem

Humans present problems for autonomous cars as both drivers and pedestrians, and dealing with our unpredictable behaviour represents a significant challenge for the technology.

The Google Car is one of the most experienced autonomous vehicles. Even so, its interaction with human drivers has given rise to the exposure of one of driverless cars’ main weaknesses. The first injury involving the Google Car wasn’t due to a fault in its system, but human-error. While correctly waiting at traffic lights, Google’s self-driving car was hit by an inattentive driver and, in spite of its sophisticated array (复杂精密的数组) of sensors, there was little it could do to avoid the incident. Luckily, the accident only resulted in minor injury for a few of the passengers, but it’s a reminder that autonomous cars are at risk when surrounded by human road users.

Despite their sophisticated systems, self-driving cars currently have no plan B for human road users. Human drivers are able to interact with each other and make allowances, but also make countless, small mistakes when driving-mistakes to which current self-driving cars simply can’t adapt.

Dealing with pedestrians

The way human drivers interact with pedestrians raises difficult moral and ethical questions for car manufacturers-with implications.

Autonomous cars need to understand the way pedestrians behave, while also imitating the behaviour they’d expect from a human driver. “Everyone has a knowledge of how a human being is going to react, because we are all human beings,” says computer ethics commentator Ben Byford. “So if you walk out in front of a car, and presumably the car driver knows you’re there, they’re going to react in a certain way.”

“ If I walked out in front of a Google car travelling at 60mph, I have no real knowledge of how the vehicle will behave, so I’m effectively putting myself in danger.”