【推荐1】Want to get your package delivered via robots? Now there’s an app for that. If you live in Washington D. C. , or Redwood, you may have glimpsed a small, boxy robot rolling along a local sidewalk, minding its own business, but attracting the attention of many curious onlookers.

The autonomous machines were part of a pilot program last year by Starship Technologies focusing on delivering meals from local restaurants in dozens of cities around the world. This week, the company unveiled plans to broaden its delivery service beyond food to include package, a move that led it to declare itself “the world’s first robot package delivery service”. The next time you order food, this cute robot might roll up to deliver it. The package delivery service is not available to everyone yet.

The wheeled robots have a top speed of 4mph and can detect obstacles from 30 feet away. “The robot can operate through anything,” Nick Handrick, head of operations for Starship’s D.C. office, said. “ If you had something in the way — a stick — it’s able to climb sticks.”

To sign up for the service, which costs a little more than $ 10 per month, customers need to download the company’s app. Customers then create a “Starship Delivery Address”, a unique address inside a Starship facility, where they can have package sent from places such as Amazon.com. Once a package is delivered to the Starship address, customers receive a text notification that allows them to schedule a home delivery via robot. The robots are opened by customers via a mobile phone code.

Barriers exist for robotic ground delivery, with many states requiring that humans be in control of delivery robots. Those regulations haven’t stopped Starship Technologies from accumulating experience on streets around the globe ahead of the company’s latest launch. The company says its robots have covered more than 125,000 miles in more than 100 cities in 20 countries.

【推荐2】Computer scientists have hoped to give robots technical skills to help them recognize, process and react to humor. But these attempts have mostly failed. AI experts say that in many cases, attempts to make robots understand humor end up producing funny results, but not in the way they were supposed to.

Tristan Miller studied more than 10,000 puns in one research project. The pun is a kind of joke that uses a word with two meanings. For example, you could say, “Balloons do not like pop music.” The word “pop” can be a way of saying popular music; or can mean the sound a balloon makes when it explodes. But a robot might not get the joke. Tristan Miller says that is because humor is a kind of creative language that is extremely difficult for computer intelligence to understand.

Allison Bishop is a computer scientist and she also performs stand-up comedy. She explained that machines are trained to look for patterns. Comedy, on the other hand, relies on things that stay close to a pattern, but not completely within it. To be funny, humor should also not be predictable, Bishop said. This is a great challenge for a machine to recognize and understand what is funny.

Bishop says since robots have great difficulty understanding humor, she feels like it gives her better job safety as a comedy performer. It even made her parents happy when her brother decided to become a full-time comedy writer because it meant he wouldn’t be replaced by a machine, she added.

Despite the difficulties, Darmstadt University’s Miller says there are good reasons to keep trying to teach humor to robots. It could make machines more relatable (叙述的), especially if they can learn to understand sarcasm (讽刺), he noted. Humans use sarcasm to say one thing but mean another. But Kiki Hempelmann thinks differently. “Teaching AI systems humor may make them find it where it isn’t, and they may use it where it’s not suitable,” he said. “Maybe bad AI will start killing people because it thinks something is funny,” he added.

【推荐3】Cool Butterfly Effect: Insect Equipment Could Inspire Heat-Radiating Tech

Devising better cooling materials has become a pressing issue as the climate warms, and some scientists are turning to nature for ideas. Small creatures with low body mass, such as insects, have to deal with the fact that they warm up much faster than large mammals. When butterflies land on tree branches in the sun, for example, their relatively large wings can overheat within seconds.

    1     Researchers have now uncovered these colorful insects' built-in cooling mechanisms.

Heat is generated by the vibration of molecules. The more molecules a material can expose on its surface, the more heat it can release in a process called radiative cooling. Those made of folded layers shaped like waves, for example, cool off much faster than solid objects because they have more exposed surface area.     2     The wings themselves are complex systems that contain both living and nonliving structures, covered by various types of scales made of chitin—a rigid substance that is also found in some fungi(真菌). The researchers found that the scales covering these structures have different shapes that radiate heat in different ways.     3    

The scientists' work is ''remarkable'', says Aaswath Raman, a professor at the University of California, Los Angeles. ''    4     Butterfly wings are extremely light, and the microstructures involved are extremely small and thin. So this discovery can inspire ways of getting rid of heat in very lightweight systems. ''

    5     It might work in a variety of colors. Many conventional buildings tend to be white because that it does not absorb heat. But painting too many things white does not look pleasing, says Qiaoqiang Gan, a photonics scientist. ''We still need a colorful world, '' Gan says, noting how vivid butterflies are in nature. ''Butterfly wings give us an example that colorful structures can also result in cooling. ''