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Categories: Mathematics: General, Physics: Acoustics and Ultrasound
Published Evaluating cybersecurity methods



Researchers created a generic framework that enables an engineer or scientist to evaluate the effectiveness of defense schemes that seek to limit a hacker's ability to learn secret information by observing the behavior of a victim computer program.
Published How secure are voice authentication systems really?



Computer scientists have discovered a method of attack that can successfully bypass voice authentication security systems with up to a 99% success rate after only six tries.
Published Researchers use ultrasound to control orientation of small particles



Acoustic waves may be able to control how particles sort themselves. While researchers have been able to separate particles based on their shape -- for example, bacteria from other cells -- for years, the ability to control their movement has remained a largely unsolved problem, until now. Using ultrasound technology and a nozzle, researchers have separated, controlled and ejected different particles based on their shape and various properties.
Published What math can teach us about standing up to bullies



New research from Dartmouth takes a fresh look at game theory to show that being uncooperative can help people on the weaker side of a power dynamic achieve a more equal outcome -- and even inflict some loss on their abusive counterpart. The findings can be applied to help equalize the balance of power in labor negotiations, international relations and everyday interactions, as well as integrate cooperation into interconnected AI systems such as driverless cars.
Published Wind farm noise exposure doesn't wake people up from their slumber more than road traffic noise



Short exposure to wind farm and road traffic noise triggers a small increase in people waking from their slumber that can fragment their sleep patterns, according to new research. But importantly, the new study also shows that wind farm noise isn't more disruptive to sleep than road traffic, which was a little more disruptive at the loudest audio level but not at more common levels. Sleep researchers have studied the impact of exposure to wind farm noise during sleep in three new scientific publications to better understand its impact.
Published When soft spheres make porous media stiffer



Porous media such as concrete physically represent a spherical packing of different components -- in this case cement, rock and water. The mechanical properties of such mixtures are still difficult to calculate due to their discretized nature. A team has now been able to investigate an unexpected property of mixtures of granular media consisting of soft and stiff spherical particles. For this purpose, a combination of ultrasound investigations and X-ray computed tomographic imaging was employed, allowing a three-dimensional (3D) characterization and evaluation. The discovery could contribute to safer future building in earthquake zones.
Published A 'spy' in the belly



To ensure that wounds remain tightly sealed in the abdomen after surgery, researchers have developed a patch with a sensor function. The polymer patch warns before the occurrence of dangerous leaks on sutures in the gastrointestinal tract take hold, while closes the areas on its own. A new material now enables a fast, easy and non-invasive leak diagnosis.
Published High-quality child care contributes to later success in science, math



Children who receive high-quality child care as babies, toddlers and preschoolers do better in science, technology, engineering and math through high school, and that link is stronger among children from low-income backgrounds, according to new research.
Published A step toward safe and reliable autopilots for flying



Researchers developed a machine-learning technique that can autonomously drive a car or fly a plane through a very difficult 'stabilize-avoid' scenario, in which the vehicle must stabilize its trajectory to arrive at and stay within some goal region, while avoiding obstacles.
Published Sponge makes robotic device a soft touch



A simple sponge has improved how robots grasp, scientists have found.
Published Reading between the cracks: Artificial intelligence can identify patterns in surface cracking to assess damage in reinforced concrete structures



Researchers are trying to make the process more efficient and definitive by using artificial intelligence, combined with a classic mathematical method for quantifying web-like networks, to determine how damaged a concrete structure is, based solely on its pattern of cracking.
Published Actively reducing noise by ionizing air



Scientists show that a thin layer of plasma, created by ionizing air, could be promising as an active sound absorber, with applications in noise control and room acoustics.
Published Source-shifting metastructures composed of only one resin for location camouflaging



Acoustic source-shifters make observers mis-perceive the location of sound by reproducing a sound emanating from a location different from the actual location of a sound source. Researchers have now developed a design approach to produce high-performance source-shifters using a common polymer for location camouflage. Utilizing inverse design based on topology optimization, this development could pave the way for advanced augmented reality and holography technology.
Published Propellers are louder over ground



The effects of the ground on propeller noise have now been measured experimentally.
Published A giant leap forward in wireless ultrasound monitoring for subjects in motion



Engineers have developed the first fully integrated wearable ultrasound system for deep-tissue monitoring, including for subjects on the go.
Published Extracting the best flavor from coffee



Researchers explore the role of uneven coffee extraction using a simple mathematical model. They split the coffee into two regions to examine whether uneven flow does in fact make weaker espresso. One of the regions in the model system hosted more tightly packed coffee than the other, which caused an initial disparity in flow resistance. The extraction of coffee decreased the flow resistance further. Understanding the origin of uneven extraction and avoiding or preventing it could enable better brews and substantial financial savings by using coffee more efficiently.
Published A cocktail party of 3D-printed robot heads



Imagine a cocktail party full of 3D-printed, humanoid robots listening and talking to each other. That seemingly sci-fi scene is the goal of an augmented listening laboratory. With precise control over the simulated subjects, the researchers can adjust the parameters of the experiment and even set the machines in motion to simulate neck movements.
Published Wearable ultrasound patch provide non-invasive deep tissue monitoring



Engineers have developed a stretchable ultrasonic array capable of serial, non-invasive, three-dimensional imaging of tissues as deep as four centimeters below the surface of human skin, at a spatial resolution of 0.5 millimeters. This new method provides a non-invasive, longer-term alternative to current methods, with improved penetration depth.
Published Sensor enables high-fidelity input from everyday objects, human body



Couches, tables, sleeves and more can turn into a high-fidelity input device for computers using a new sensing system.
Published Unraveling the mathematics behind wiggly worm knots



Researchers wanted to understand precisely how blackworms execute tangling and ultrafast untangling movements for a myriad of biological functions. They researched the topology of the tangles. Their research could inform the design of fiber-like, shapeshifting robotics that self-assemble and move in ways that are fast and reversible.