Engineering
A research team led by Lim Sang-kyoo, senior researcher of the Division of Energy Technology at DGIST (President Kuk Yang) developed a piezoelectric polymer/ceramic composite fiber with a cross-sectional form that is uniformly ...
Aug 12, 2022
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13
Electronics & Semiconductors
Imagine this: A smooth touchscreen display placed on top of a thin silicone polymer film suddenly generates the feeling of a tiny raised button under the user's finger. Or how about the idea of wearing that same polymer film ...
May 24, 2022
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162
Engineering
The aviation industry faces multiple pressures from higher fuel costs and increased scrutiny over the environmental and quality-of-life impacts from its aircraft. Researchers are looking for new methods of keeping expenses ...
May 10, 2022
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225
Engineering
A new type of lightweight, 3D-printed heat exchanger with a maze-like design is more compact and efficient than its conventional counterparts, its developers say.
Apr 5, 2022
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309
Energy & Green Tech
From cell to module without loss of efficiency: This is one of the main challenges of perovskite photovoltaics. Researchers at Karlsruhe Institute of Technology (KIT) have now managed to produce perovskite solar modules with ...
May 7, 2021
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7
Engineering
Two researchers at the Chinese University of Hong Kong have developed a new membrane design that prevents crossover in polysulfide redox flow batteries. In their paper published in the journal Nature Energy, Zhejun Li and ...
Energy & Green Tech
Solar power is now the cheapest source of electricity in history, according to a 2020 report by the International Energy Agency. But there's something holding this clean energy powerhouse back: space. Unlike fossil fuel power ...
Apr 13, 2021
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12
Engineering
With the ever-increasing worldwide mass production of plastic, the inefficiency of current plastic recycling strategies has raised several environmental, societal, and economic concerns. Magnetic density separation (MDS) ...
Feb 26, 2021
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322
Telecom
German ministers agreed Monday to spend more than one billion euros plugging gaps in its mobile phone networks, whose patchy coverage has been blasted as "embarrassing" for the advanced industrial nation.
Nov 18, 2019
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3
Machine learning & AI
Thunderstorms are common all over the world in summer. As well as spoiling afternoons in the park, lightning, rain and strong winds can damage power grids and cause electricity blackouts. It's easy to tell when a storm is ...
Jul 30, 2019
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Surface area is the measure of how much exposed area a solid object has, expressed in square units. Mathematical description of the surface area is considerably more involved then the definition of arc length of a curve. For polyhedra (objects with flat polygonal faces) the surface area is the sum of the areas of its faces. Smooth surfaces, such as a sphere, are assigned surface area using their representation as parametric surfaces. This definition of the surface area is based on methods of infinitesimal calculus and involves partial derivatives and double integration.
General definition of surface area was sought by Henri Lebesgue and Hermann Minkowski at the turn of the twentieth century. Their work led to the development of geometric measure theory which studies various notions of surface area for irregular objects of any dimension. An important example is the Minkowski content of a surface.
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