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- To become autonomous, robots need to perceive the world around them and move at the same time.
- Researchers create a theory of hyperdimensional computing to help store robot movement in high-dimensional vectors.
- This improvement in perception will allow artificial intelligences to create memories.
Do androids dream of electric sheep? Philip K. Dick famously wondered that in his stories that explored what it meant to be human and robot in the age of advanced and widespread artificial intelligence. We aren't quite in "Blade Runner" reality just yet, but now a team of researchers came up with a new way for robots to remember that may close the gap between robots and us for good.
For robots to be as proficient as humans in various tasks, they need to coordinate sensory data with motor capabilities. Scientists from the University of Maryland published a paper in the journal Science Robotics describing a potentially revolutionary approach to improve how AI handles sensorimotor representation using hyperdimensional computing theory.
What the researchers set out to create was a way to improve a robot's "active perception" - its ability to integrate how it perceives the world around it with how it moves in that world. As they wrote in their paper, "we find that action and perception are often kept in separated spaces," which they attribute to traditional thinking.
They proposed instead "a method of encoding actions and perceptions together into a single space that is meaningful, semantically informed, and consistent by using hyperdimensional binary vectors (HBVs). "
As their press release explains, HBVs work in very high-dimensional spaces, containing a plethora of information about different discrete items like an image or a sound or a command. These can be further grouped into sequences of discrete items and groupings of items and sequences.
By utilizing these vectors, the researchers look to keep all sensory information the robot receives in one place, essentially creating its memories. As more information gets stored, "history" vectors would be created, increasing the robot's memory content.
The scientists think that active perception and memories would make the robots better at autonomous decisions, expecting future situations and completing tasks.
The Hyperdimensional "pipeline"
Credit: Perception and Robotics Group, University of Maryland.
This "pipeline" describes how data from a drone flight is recorded and translated into binary vectors that are integrated into memory through vector operations. This memory can then be recalled.
"An active perceiver knows why it wishes to sense, then chooses what to perceive, and determines how, when and where to achieve the perception," said Aloimonos. "It selects and fixates on scenes, moments in time, and episodes. Then it aligns its mechanisms, sensors, and other components to act on what it wants to see, and selects viewpoints from which to best capture what it intends. Our hyperdimensional framework can address each of these goals."
Outside of robots, the scientists also see an application of their theories in deep learning AI methods employed in data mining and visual recognition.
To test the theory, the team employed a dynamic vision sensor (DVS) which continually captures the edges of objects in event clouds as they move by. By quickly focusing on the contours of the scene and the movement, this sensor is well-suited for autonomous navigation of robots. The data from the event clouds is stored in binary vectors, allowing the scientists to apply hyperdimensional computing.
Here’s a video of how DVS works:
The research was carried out by the computer science Ph.D. students Anton Mitrokhin and Peter Sutor, Jr., along with Cornelia Fermüller, an associate research scientist with the University of Maryland Institute for Advanced Computer Studies, as well as the computer science professor Yiannis Aloimonos. He advised Mitrokhin and Sutor.
Check out their paper "Learning sensorimotor control with neuromorphic sensors: Toward hyperdimensional active perception" in Science Robotics.
- How bad is wealth inequality in the United States? About 1 percent of Americans hold 80 percent of the money.
- In the United States, the correlation between the income of parents and the income of their children when they grow up is higher than in any other country in the world.
- One of the big underlying reasons for poverty is receiving a crummy education, which in turn leads to crummy jobs. When people recognize their miserable long-term prospects, they are more likely to partake in riots.
- The American society is close to split on the legality of abortions.
- 45,789,558 abortions were carried out in the U.S. between 1970 and 2015.
- The abortion numbers are at an all-time low now, trending almost half of what they were.
WHAT AMERICANS THINK ABOUT ABORTION
Abortion is an extremely divisive issue that splits the country close to down the middle. About 48% of Americans consider themselves "pro-choice," but the same number – 48% are "pro-life," found a May 2018 Gallup poll. The numbers of pro-choicers is higher, however, in a Pew Research Poll from October 2018 which counted 58% of Americans saying abortion should be almost always legal in contrast to 37% who thought abortion should in illegal in most cases.
The views continue to go in separate ways when you drill down further. With regards to first trimester abortions, 90% of pro-choice Americans support their legality in most cases, while 60% of pro-life voters think it should be illegal [Gallup].
In the political arena, the divide couldn't be more clear. 59% of Republicans think abortion should be mostly illegal, while 76% of Democrats say abortion should be legal in most cases, discovered the Pew Center poll. Notably, these positions have become hardened over time as in 1995, just 49% of Republicans supported keeping abortion legal and 64% of Democrats.
Where Americans do seem to agree is in cases where a woman's life is in danger, with 83% saying abortion should be legally allowed (including 71% of pro-lifers). In cases of rape and incest, 77% support abortion rights (96% of pro-choicers and 57% of pro-life Americans). [Gallup].
While Americans take complex positions on abortion, it should be pointed out that only 18% of all U.S. adults think it should be illegal in all circumstances. Most support some form of abortion being allowed.
WHAT ALABAMIANS THINK ABOUT ABORTION
In Alabama, the ground zero of the abortion debate due to a recently passed abortion ban, repeated polling has shown that most of the voters oppose abortion rights, women included. A 2014 Pew Research Center poll found 58% of residents saying abortion should be illegal in mostly all cases. 51% of the pro-life respondents were women. Other polling indicates similar patterns.
The New York Times reports that in 2017, the citizens of Alabama approved modifying the State Constitution to include the language that the state must "to recognize and support the sanctity of unborn life and the rights of unborn children, including the right to life."
Most Alabamians, however, do think the extreme abortion ban recently passed by their legislature goes too far. Only 31% supported having no rape/incest exception in a 2018 poll.
Americans generally agree on the legality of abortions in cases of a woman's life being endangered or those involving rape and incest.
HOW MANY ABORTIONS ARE PERFORMED
According to CDC stats, 638,169 abortions were performed in 2015. Compare that to the period from the late 70s till the late 90s when the number of abortions was regularly fluctuating between 1 - 1.4 million per year.
Taken as a whole, there were 45,789,558 abortions performed in the U.S. between 1970 and 2015.
While lower, it is still a fairly widespread procedure, with about 23.7% of American women having an abortion before reaching 45, concluded Guttmacher Institute's 2017 research. Before 30, the percentage is 19%. Before 20 it's 4.6%.
In Alabama, the numbers went from 11,267 abortions in 2007 to 6,768 abortions in 2017.
Think of the last time you had something to celebrate. If you toasted the happy occasion, your drink was probably alcoholic – and bubbly.
Have you ever wondered why it's so enjoyable to imbibe a glass of something that sets off a series of microexplosions in your mouth?
A glass of a bubbly drink is full of physics, history and culture. We probably first encountered fizz alongside the discovery of alcohol, since both ethanol and carbon dioxide (CO2) gas are byproducts of fermentation. Drinking carbonated substances for pleasure – rather than simply staying hydrated – appears to be something only humans do.
In 17th-century France, the Benedictine monk Dom Pérignon greatly refined what we now know as Champagne. It took him many years to perfect a bottle and cork design that could withstand the high pressures that the process required. In sparkling wine, part of the fermentation takes place after the liquid has been bottled. Since the CO2 can't escape the closed container, the pressure builds inside. In turn, this results in large gas quantities being actually dissolved into the liquid, in accordance with Henry's law – a rule stating that the amount of gas that can be dissolved in a liquid is proportional to the pressure.
Among other things, Henry's law explains why divers can get decompression sickness if they rush their ascent to the surface: at great depths, the body is exposed to a high pressure and, consequently, gases are dissolved in blood and tissues in high concentrations. Then, when surfacing, the pressure returns to the ambient level, such that the gas 'exsolves' and is released to form painful, harmful bubbles in the body. The same happens when we uncork a bottle of Champagne: the pressure suddenly drops back to its atmospheric value, the liquid becomes supersaturated with carbon dioxide – et voilà, bubbles emerge!
Over time, as liquid continues releasing gas, the size of the bubbles grows, and their buoyancy increases. Once the bubbles get sufficiently big, they can't stay stuck to the microscopic crevices in the glass where they originally formed, and so they rise to the surface. Soon after, a new bubble forms and the process repeats itself. That's why you've probably observed bubble chains forming in Champagne glasses – as well as the sad tendency of fizzy drinks to go flat after a while.
Intriguingly, Gérard Liger-Belair, professor of chemical physics at the University of Reims Champagne-Ardenne in France, discovered that most of the gas lost to the atmosphere in sparkling wine doesn't escape in the form of bubbles, but from the surface of the liquid. However, this process is highly enhanced by the way that bubbles encourage the Champagne to flow in the glass. In fact, if there were no bubbles, it would take weeks for a drink to lose its carbon dioxide.
The attractive bubbly character of Champagne can be found in other drinks, too. When it comes to beer and carbonated water, the bubbles don't come from fermentation but are introduced artificially by bottling the liquid at high pressure with an excess amount of carbon dioxide. Again, when opened, the gas can't stay dissolved, so bubbles emerge. Artificial carbonation was actually discovered by the 18th-century English chemist Joseph Priestley – better known for discovering oxygen – while investigating a method to preserve drinking water on ships. Carbonated water also occurs naturally: in the southern French town of Vergèze – where Perrier, the commercial brand of mineral water, is bottled – an underground water source is exposed to carbon dioxide at high pressure, and comes up naturally fizzy.
When a carbonated beverage is rich in contaminants that stick to the surface, known as surfactants, bubbles might not burst when they reach the top but accumulate there as foam. That's what gives beer its head. In turn, this foam affects the texture, mouthfeel and flavour of the drink. From a more physical perspective, foam also insulates the drink, keeping it colder for a longer time and acting as a barrier to the escape of carbon dioxide. This effect is so important that in the Dodger Stadium in Los Angeles beer is sometimes served with a head of artificial foam. Recently, researchers have discovered another interesting effect: a foam head prevents the beer from spilling when one walks with an open glass in hand.
Despite our solid understanding of bubble formation in drinks, a question remains: just why do we like drinks with bubbles? The answer remains elusive, but some recent studies can help us understand. The interaction of carbon dioxide with certain enzymes found in saliva causes a chemical reaction that produces carbonic acid. This substance is believed to stimulate some pain receptors, similar to those activated when tasting spicy food. So it seems that the so-called 'carbonation bite' is a kind of spicy reaction – and humans (strangely) seem to like it.
The presence and size of bubbles can even affect our perception of flavour. In a recent study, researchers found that people could experience the bite of carbonic acid without bubbles, but bubbles did change how things tasted. We still don't have a clear picture of the mechanism by which bubbles influence flavour, though soft-drink manufacturers have ways of adjusting the amount of carbonation according to the sweetness and nature of the drink. Bubbles also affect the rate at which alcohol is assimilated into the body – so it's true that a bubbly drink will make you feel inebriated more quickly.
As far as we're concerned, all this offers a great excuse to talk about physics. We enjoy bubbly drinks too, of course – but personally, we celebrate adding a touch of science to a subject so that most people can relate to it. What's more, bubbly liquids have many practical applications. They're essential to some techniques for extracting oil; for explaining deadly underwater explosions known as limnic eruptions; and for understanding many other geological phenomena, such as volcanoes and geysers, whose activity is strongly influenced by the formation and growth of gas bubbles in the erupting liquid. So, the next time you celebrate and knock back a glass of bubbly, be sure to know that physics contributes to the sum of human happiness. Salud!
This article was originally published at Aeon and has been republished under Creative Commons.
- Machines can help doctors by spotting abnormalities in X-rays or MRA scans that the physicians themselves may have missed.
- A.I. can also help physicians by analyzing data and, through the use of algorithms, produce possible diagnoses.
- The freed up time, as doctors make their rounds, can help physicians establish better connections with their patients, which in turn can lead to better treatment plans.