A new algorithm(演算法)raises parking rates in busy neighborhoods and lowers them elsewhere，guaranteeing free parking spots regardless of location，Christopher Intagliata reports.

If you drive in a city，you’ve no doubt experienced the headache of circling block after block，cruising for parking.But scientists who study that phenomenon have a solution to free up more spots:“You make them more expensive，so people have to decide whether to park farther away and Pay less，or closer and pay more.”Itzhak Benenson，a system scientist at Tel Aviv University.

San Francisco has piloted a program that raises parking rates based on demand—and it's been shown to reduce cruising.But the sensors required for those systems can cost millions of dollars to install and operate，Benenson says.So instead，writing in IEEE Intelligent Transportation Systems Magazine，he and his colleague Nir Fulman describe an algorithm that can determine smart pricing，without the use of sensors.

They tested it on the Israeli city of Bat Yam，near Tel Aviv.First，they divide the city into zones.They estimate the parking demand in each zone，by calculating the number of apartments and offices there.Then they take account of parking supply in the area，along with how wealthy potential parkers might be.Using that data，the algorithm suggested pricing for each zone that would guarantee a 90-percent occupancy rate of parking spots city-wide.Meaning 10 percent of spots were always available to drivers willing to pay the price，regardless of neighborhood.

Of course，not everyone will agree that raising parking prices will reduce the press of parking.Last time Benenson proposed hiking rates for city residents?“I got about 100 reactions on the web and 99 of them that said they have never heard such a stupid statement from the professors，and I should be punished and fired.”

Eventually，he says，it'll be up to cities themselves to estimate their residents’political appetites for an easier parking spot.

Getting stuck in a traffic jam is one of the most boring problems for people living in big cities.The fact that you’re moving so slowly leads too stress,anger and the wish that your car could just fly over the traffic like an airplane.

Soon,however, that wish could come true .On May 8, US car-renting company Uber showed off what it described as “the transportation mode of the future: on-demand air   transport,”reported ABC News .

According to Nikhill Goel, head of products for Uber Air, the company's air taxi service may launch test flights in the US cities of Dallas and Los Angeles , as well as Dubai in the United Arab Emirates, as early as 2020. If everything goes according to plan, passengers will be able to fly to work by 2023 .

When the Olympics comes to Los Angeles in 2028 . Uber “expects to have hundreds , if not thousands , of its aircraft in the skies.” Goel told Newsweek .

So what would Uber's flying vehicles be like ?

They are small , electric aircraft that take off and land vertically (垂直地) , and they give off zero emissions (排放) and are quiet enough to operate in cities .

Just like an airplane , the vehicles will have fixed wings to help them glide . But while a helicopter has just one big fixed rotor (定量) . Uber's vehicles will have multiple rotors , which will help increase fuel efficiency (效率) while reducing emissions and noise.

Because of these fixed wines and multiple rotors . Uber’s flying taxis“should be quieter and safer than a helicopter.” reported ABC News .

However , the service still has a long way to go before it's ready to accept passengers.For example , to avoid any potential accidents . Uber is working with NASA to study air traffic control problems associated with low-flying aircraft. But just as Dubai's Mayor Betty Price said in a news release . “This program is revolutionary and future -oriented (面向未来的). ”