In this edition of Talk Nerdy we look at earth-friendly ways to produce power and fuel; new hope for the voiceless; protecting society from deepfakes; and getting ahead of deadly heatwaves.
You have the power
Once upon a time in TV Land, the Professor on Gilligan’s Island generated electricity via a stationary bike made of bamboo. Now scientists have developed a new technology that harvests energy from the human knee using a similar concept, but it’s for real.
A group of researchers at the Chinese University of Hong Kong (CUHK) have developed a device that attaches to the knee and generates power as the wearer walks. The smart microfiber material produces energy with any bending motion.
The device prototype weighs only .68 pounds. When tested on people, they found no extra energy was expended when walking with the attachment, so there’s no cost to the wearer. CUHK engineering professor Wei-Hsin Liao believes that a knee-powered GPS device will be a boon to outdoors enthusiasts like climbers and mountaineers.
Voice tattoo
Temporary tattoos can be a fun way to dress up for special occasions or add effects to a great costume, but what if they could help people who have lost the ability to speak? Researchers at Tsinghua University in China are working on a way to help people whose vocal cords are damaged by developing a wearable artificial throat that can transform movement into sound.
The researchers made the skin-like device by laser-scribing graphene onto a thin sheet of polyvinyl alcohol film. Water is used to attach the film to the skin over a person’s throat. They then connected it with electrodes to a circuit board, microcomputer, power amplifier, and decoder located on a small armband.
The device produced sounds when the volunteer noiselessly imitated throat motions of speech. The researchers think that mute people can someday be trained to generate signals with their throats that the device can convert to speech.
Detecting deepfakes
We used to say that “seeing is believing.” But now deepfake videos should make us question everything we see. By mapping the facial expressions of an actor onto footage of someone else, deepfake producers can make a public figure say anything they want. In politics, this could easily undermine opponents and deceive the public. So how can we avoid being duped by deepfakes?
Amit Roy-Chowdhury and his Video Computing Group at the University of California, Riverside have developed a deep neural network that can spot manipulated images with high precision. The network has been trained to recognize images that have been altered at the pixel level, by examining the boundaries of objects. When an object’s boundaries are changed, its qualities no longer match those of the original image. The human eye might not notice these differences, but the neural network can examine the boundary pixel-by-pixel and spot the changes.
For now, the researchers are working on still images, but they say the findings will help them detect deep fake videos. But in the meantime, we will have to rely on human vigilance to prevent being fooled.
Predicting killer heat waves
Just this week, a heatwave in Japan killed eleven people and temperatures in Paris have reached the highest ever recorded. If governments had advance warnings that their cities were about to be turned into ovens, it would give authorities time to gather resources and prepare facilities to help communities withstand the heat.
To get better at predicting heat waves, meteorologists have been looking at the Madden-Julian Oscillation (MJO). This atmospheric phenomenon is a disturbance of clouds, rainfall, winds, and pressure that forms over the Indian Ocean and then traverses the planet. Scientists at the National Center for Atmospheric Research (NCAR) are developing a short-term model to forecast extreme heat based on historical MJO patterns.
But one problem they face is how exactly to define a heatwave. Conditions vary in different regions, and average temperatures continue to climb due to global warming. Still, NCAR scientists hope that by the end of the year, they will be able to predict periods of extreme heat three to four weeks in advance.
Powering your car with microorganisms
Researchers at Uppsala University in Sweden have successfully created microorganisms that can produce the alcohol butanol (a potential biofuel). Microscopic cyanobacteria are the most efficient photosynthetic organisms on earth. Newly modified versions of them produce butanol using carbon dioxide and solar energy without the use of solar cells.
This lab-produced butanol could be used as both vehicle fuel and as a component in environmentally-friendly rubber for tires. The scientists hope that in the future we will be able to replace fossil fuels with a carbon-neutral product created from just solar energy, carbon dioxide, and water.