Kolmogorov complexity In algorithmic information theory (a subfield of computer science and mathematics), the Kolmogorov complexity (also known as descriptive complexity, Kolmogorov–Chaitin complexity, algorithmic entropy, or program-size complexity) of an object, such as a piece of text, is a measure of the computability resources needed to specify the object. It is named after Andrey Kolmogorov, who first published on the subject in 1963. abababababababababababababababab 4c1j5b2p0cv4w1x8rx2y39umgw5q85s7 The first string has a short English-language description, namely "ab 16 times", which consists of 11 characters. More formally, the complexity of a string is the length of the shortest possible description of the string in some fixed universal description language (the sensitivity of complexity relative to the choice of description language is discussed below). Definition Any string s has at least one description, namely the program: function GenerateFixedString() return s K(s) = |d(s)|. ∀s. ∀s.
The Rabbit-Hole | DIY UAVs for Cyber Warfare – Wireless Aerial Surveillance Platform List of emerging technologies Agriculture Biomedical Displays Electronics Energy IT and communications Manufacturing Materials science Military Neuroscience Robotics Transport Other See also General Disruptive innovation, Industrial Ecology, List of inventors, List of inventions, Sustainable development, Technology readiness level Nano- Molecular manufacturing, Neurotechnology Bioscience Human Connectome Project Ethics Casuistry, Computer ethics, Engineering ethics, Nanoethics, Bioethics, Neuroethics, Roboethics Other Anthropogenics, Machine guidance, Radio frequency identification, National Science Foundation, Virtual reality Transport List of proposed future transport Further reading IEEE International Conference on Emerging Technologies and Factory Automation, & Fuertes, J. References External links
How I Accidentally Kickstarted the Domestic Drone Boom | Danger Room At last year’s Paris Air Show , some of the hottest aircraft were the autonomous unmanned helicopters—a few of them small enough to carry in one hand—that would allow military buyers to put a camera in the sky anywhere, anytime. Manufactured by major defense contractors, and ranging in design from a single-bladed camcopter to four-bladed multicopters, these drones were being sold as the future of warfare at prices in the tens to hundreds of thousands of dollars. In May, at a different trade show, similar aircraft were once again the most buzzed-about items on display. But this wasn’t another exhibition of military hardware; instead, it was the Hobby Expo China in Beijing, where Chinese manufacturers demo their newest and coolest toys. Companies like Shenzhen-based DJI Innovations are selling drones with the same capability as the military ones, sometimes for less than $1,000. What are all these amateurs doing with their drones? Why? What exactly do we mean by drone? Go Back to Top.
Holography Two photographs of a single hologram taken from different viewpoints The holographic recording itself is not an image; it consists of an apparently random structure of either varying intensity, density or profile. Overview and history The Hungarian-British physicist Dennis Gabor (in Hungarian: Gábor Dénes), was awarded the Nobel Prize in Physics in 1971 "for his invention and development of the holographic method". His work, done in the late 1940s, built on pioneering work in the field of X-ray microscopy by other scientists including Mieczysław Wolfke in 1920 and WL Bragg in 1939. The discovery was an unexpected result of research into improving electron microscopes at the British Thomson-Houston (BTH) Company in Rugby, England, and the company filed a patent in December 1947 (patent GB685286). Several types of holograms can be made. Holograms can also be used to store, retrieve, and process information optically. How holography works Recording a hologram
2013 - February 15-17 - Speakers Keynote Address Privacy Online: What Now? Ian Goldberg Recent revelations about data and metadata collection of Internet users' communications have been extremely worrying. Not only are governments collecting this information, but online service providers, including cloud providers, are part of the picture as well. What can we, as individuals, do to limit the collection of our online messages, friends lists, and usage patterns? Ian Goldberg is an Associate Professor of Computer Science and a University Research Chair at the University of Waterloo, where he is a founding member of the Cryptography, Security, and Privacy (CrySP) research group. Closing Plenary Large Scale Network and Application Scanning Bruce Potter (moderator), Robert David Graham, Paul McMillan, Dan Tentler, and Alejandro Caceres Back in 1998, Robert Graham created one of the first popular desktop firewalls (BlackICE Defender) and the first IPS (BlackICE Guard). Paul McMillan is a security engineer at Nebula. Assambly
John Conway's Game of Life The Game The Game of Life is not your typical computer game. It is a 'cellular automaton', and was invented by Cambridge mathematician John Conway. This game became widely known when it was mentioned in an article published by Scientific American in 1970. It consists of a collection of cells which, based on a few mathematical rules, can live, die or multiply. playgameoflife.com New developments of this page will continue on playgameoflife.com. playgameoflife.com The Simulation Figure from the XKCD RIP John Conway comic. The Rules For a space that is 'populated': Each cell with one or no neighbors dies, as if by solitude. Each cell with four or more neighbors dies, as if by overpopulation. Each cell with two or three neighbors survives. For a space that is 'empty' or 'unpopulated' Each cell with three neighbors becomes populated. The Controls Choose a figure from the pull-down menu or make one yourself by clicking on the cells with a mouse. Development Edwin Martin <firstname.lastname@example.org>
A newbie's guide to UAVs What is an amateur UAV? An Unmanned Aerial Vehicle (UAV) is an aircraft that has the capability of autonomous flight, without a pilot in control. Amateur UAVs are non-military and non-commercial. They typically fly under “recreational” exceptions to FAA regulations on UAVs, so long as the pilots/programmers keep them within tight limits on altitude and distance. What do I need to make one? ---1) An RC plane, muticopter (quadcopter/hexacopter/tricopter, etc) or helicopter. What does DIY Drones have to offer? The DIY Drones community has created the world's first "universal autopilots", ArduPilot Mega (APM) and its next-generation big brother, Pixhawk. A full setup consists of: Pixhawk autopilot: The electronics, including twin processors, gyros, accelerometers, pressure sensors, GPS and more (shown at right). You can buy Ready-to-Fly UAVs (both planes and multicopters) from 3D Robotics: Last but not least is flight safety. Also, here's the FAA's official word on what's legal and what's not.