Tournament selection, roulette selection, mutation, crossover — all processes used in genetic algorithms. Dr Alex Turner explains using the Knapsack Problem.
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Papilio antimachusPhoto by Luis Miguel Bugallo Sánchez (Lmbuga Commons)(Lmbuga Galipedia); CC-BY-SA-3.0 The Giant African Swallowtail (Papilio antimachus) is a species of giant butterfly in the family of swallowtail butterflies. As a giant butterfly, Papilio antimachus belongs to the family Papilionidae and has a wingspan of between 7.1 and 9.1 inches. It is not unusual to see wings that can measure 10 inches or more from tip to tip.
Robert McNair Price (born 7 July 1954) is an American New Testament scholar who argues against the existence of a historical Jesus (the Christ myth theory). He taught theology and religious studies at the Johnnie Colemon Theological Seminary. Price is a professor of biblical criticism at the Center for Inquiry Institute, and the author of a number of books on biblical studies and the historicity of Jesus.
A former Baptist minister, Price was the editor of the Journal of Higher Criticism from 1994 until it ceased publication in 2003. He has also written extensively about the Cthulhu Mythos, a “shared universe” created by the writer H. P. Lovecraft. He also co-wrote a book with his wife, Carol Selby Price, Mystic Rhythms: The Philosophical Vision of Rush (1999), on the rock band Rush.
A team of researchers in China have developed a high-conductivity material that could greatly reduce contact resistance and Schottky barrier height within critical parts of electronic and optoelectronic microchips, paving the way for computer and digital imaging components that consume less power relative to their performance than existing chipsets.
The material, molybdenum disulfide (MoS2) is so thin that it falls into a classification of two-dimensional. That is, it is grown in sheets extending in two directions, X and Y, but virtually immeasurable on a Z axis because the material is often only a single molecule or atom in height.
The team, led by Professor Dong Li and Professor Anlian Pan, College of Materials Science and Engineering at Hunan University, published their findings in Nano Research.
A research team from Skoltech, Aalto University, and Kurnakov Institute has recently developed a new, versatile and simple approach to using carbon nanotubes for manufacturing carbon nanotube-polymer nanocomposites. The method is reported in Carbon and involves making briquettes—dense packages of carbon nanotube powders. Nanocomposites made with briquettes perform equally well as those made from the more expensive masterbatches, which are also polymer-specific—that is, less versatile.
“We believe the use of dense briquettes of carbon nanotubes can significantly facilitate the development of the carbon nanotube composite industry. This technique is cheap and applicable to a broad variety of polymer matrices, without sacrificing any of the electrical and thermal properties of the final material,” the lead author of the study, Skoltech Ph.D. student Hassaan Butt, stated.
Carbon nanotubes have been intensively investigated for decades by researchers from academia and industry because of their unique combination of electrical, thermal, and mechanical properties. Meanwhile, polymer-based nanocomposites have come to be the largest carbon nanotube application and the one closest to widespread integration into everyday life. It is easy to understand why: The smallest amounts of nanotubes added to a polymer endow the material with fundamentally new properties, such as electrical conductivity and piezoresistivity, as well as crucially enhancing its thermal and mechanical properties.
Lawrence Livermore National Laboratory (LLNL) scientists are scaling up the production of vertically aligned single-walled carbon nanotubes (SWCNT) that could revolutionize diverse commercial products ranging from rechargeable batteries, automotive parts and sporting goods to boat hulls and water filters. The research appears in the journal Carbon.
Most CNT production today is used in bulk composite materials and thin films, which rely on unorganized CNT architectures. For many uses, organized CNT architectures such as vertically aligned forests provide important advantages for exploiting the properties of individual CNTs in macroscopic systems.
“Robust synthesis of vertically-aligned carbon nanotubes at large scale is required to accelerate deployment of numerous cutting-edge devices to emerging commercial applications,” said LLNL scientist and lead author Francesco Fornasiero. “To address this need, we demonstrated that the structural characteristics of single-walled CNTs produced at wafer scale in a growth regime dominated by bulk diffusion of the gaseous carbon precursor are remarkably invariant over a broad range of process conditions.”
Thin films made of carbon nanotubes hold a lot of promise for advanced optoelectronics, energy and medicine, however with their manufacturing process subject to close supervision and stringent standardization requirements, they are unlikely to become ubiquitous anytime soon.
“A major hindrance to unlocking the vast potential of nanotubes is their multiphase manufacturing process which is extremely difficult to manage. We have suggested using artificial neural networks (ANN) to analyze experimental data and predict the efficiency of single-walled carbon nanotubes synthesis,” explains one of the authors of the study and Skoltech researcher, Dmitry Krasnikov.
In their work published in the prestigious Carbon journal, the authors show that machine learning methods, and, in particular, ANN trained on experimental parameters, such as temperature, gas pressure and flow rate, can help monitor the properties of the carbon nanotube films produced.
This is number 22 on IE’s list of 22 best innovations, a look back at recycling for all plastics.
Two companies, Plastonix and Elemental Recycling have done what others could not: they have found technologies that recycle all types of plastic.
The monumental task of recycling the 380 million tons of plastic disposed of each year, that clog the ocean and beaches throughout the world, has eluded us. Around 80 percent of all plastic ends up in the oceans and landfills.
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Americium-241 emits power for more than 400 years.
The world’s first space battery fueled by Americium-241, a nuclear-based fuel, will be developed in cooperation between the National Nuclear Laboratory (NNL) and the U.K. Space Agency.
This project will be carried out in a brand-new laboratory in Cumbria costing £19 million ($23 million) and outfitted with cutting-edge machinery and technology, according to a joint press release by NNL and the Space Agency on Friday.
Ever skip stones across a pond? Imagine doing it with a spacecraft.
When NASA’s Orion returns to Earth on Dec. 11 at the end of the Artemis I mission, it will attempt a guidance and control maneuver called a skip-entry – the first time a skip entry maneuver will be attempted for a human spacecraft.
