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🔗 Technology

KarTrak, sometimes KarTrak ACI (for Automatic Car Identification) is a colored bar code system designed to automatically identify rail cars and other rolling stock. KarTrak was made a requirement in North America, but technical problems led to abandonment of the system in the late 1970s.

🔗 India 🔗 India/Kerala

ka·ṭa·pa·yā·di (Devanagari: कटपयादि) system (also known as Paralppēru, Malayalam: പരല്‍പ്പേര്) of numerical notation is an ancient Indian alphasyllabic numeral system to depict letters to numerals for easy remembrance of numbers as words or verses. Assigning more than one letter to one numeral and nullifying certain other letters as valueless, this system provides the flexibility in forming meaningful words out of numbers which can be easily remembered.

🔗 Computing 🔗 Electronics 🔗 Electrical engineering

An asynchronous circuit, or self-timed circuit, is a sequential digital logic circuit which is not governed by a clock circuit or global clock signal. Instead it often uses signals that indicate completion of instructions and operations, specified by simple data transfer protocols. This type of circuit is contrasted with synchronous circuits, in which changes to the signal values in the circuit are triggered by repetitive pulses called a clock signal. Most digital devices today use synchronous circuits. However asynchronous circuits have the potential to be faster, and may also have advantages in lower power consumption, lower electromagnetic interference, and better modularity in large systems. Asynchronous circuits are an active area of research in digital logic design.

🔗 Game theory

Sprouts is a paper-and-pencil game that can be enjoyed simply by both adults and children. Yet it also can be analyzed for its significant mathematical properties. It was invented by mathematicians John Horton Conway and Michael S. Paterson at Cambridge University in the early 1960s. Setup is even simpler than the popular Dots and Boxes game, but game-play develops much more artistically and organically.

🔗 United States 🔗 Numismatics 🔗 Numismatics/American currency

The half cent was the smallest denomination of United States coin ever minted. It was first minted in 1793 and last minted in 1857. It was minted with five different designs.

🔗 Biography 🔗 United Kingdom 🔗 Ships

The rescue of Roger Mallinson and Roger Chapman occurred between 29 August and 1 September 1973 after their Vickers Oceanics small submersible Pisces III was trapped on the seabed at a depth of 1,575 ft (480 m), 150 mi (240 km) off Ireland in the Celtic Sea. The 76-hour multinational rescue effort resulted in the deepest sub rescue in history.

🔗 United States 🔗 Brands 🔗 Record Labels 🔗 United States/American music

The Edison Diamond Disc Record is a type of phonograph record marketed by Thomas A. Edison, Inc. on their Edison Record label from 1912 to 1929. They were named Diamond Discs because the matching Edison Disc Phonograph was fitted with a permanent conical diamond stylus for playing them. Diamond Discs were incompatible with lateral-groove disc record players, e.g. the Victor Victrola, the disposable steel needles of which would damage them while extracting hardly any sound. Uniquely, they are just under 1⁄4 in (6.0 mm; 0.235 in) thick.

Edison had previously made only phonograph cylinders but decided to add a disc format to the product line because of the increasingly dominant market share of the shellac disc records (later called 78s because of their typical rotational speed in revolutions per minute) made by competitors such as the Victor Talking Machine Company. Victor and most other makers recorded and played sound by a lateral or side-to-side motion of the stylus in the record groove, while in the Edison system the motion was vertical or up-and-down, known as vertical recording, as used for cylinder records. An Edison Disc Phonograph is distinguished by the diaphragm of the reproducer being parallel to the surface of the record. The diaphragm of a reproducer used for playing lateral records is at a right angle to the surface.

In the late summer and early fall of 1929 Edison also briefly produced a high-quality series of thin electrically recorded lateral-cut "Needle Type" disc records for use on standard record players.

🔗 Soviet Union 🔗 Spaceflight 🔗 Dogs 🔗 Animal rights

During the 1950s and 1960s the Soviet space program used dogs for sub-orbital and orbital space flights to determine whether human spaceflight was feasible. In this period, the Soviet Union launched missions with passenger slots for at least 57 dogs. The number of dogs in space is smaller, as some dogs flew more than once. Most survived; the few that died were lost mostly through technical failures, according to the parameters of the test.

A notable exception is Laika, the first dog to be sent into orbit, whose death during the 3 November, 1957 Sputnik 2 mission was expected from its outset.

🔗 Espionage 🔗 Companies 🔗 Military history 🔗 Military history/Military aviation 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry 🔗 Business 🔗 Military history/Maritime warfare 🔗 Military history/European military history 🔗 Military history/British military history 🔗 Military history/Military historiography

Jane's Information Group, now styled Janes, is a global open-source intelligence company specialising in military, national security, aerospace and transport topics, whose name derives from British author Fred T. Jane.

🔗 Computing 🔗 Computer Security 🔗 Computer Security/Computing 🔗 Computing/Computer Security 🔗 Computing/Networking

Warchalking is the drawing of symbols in public places to advertise an open Wi-Fi network. Inspired by hobo symbols, the warchalking marks were conceived by a group of friends in June 2002 and publicised by Matt Jones who designed the set of icons and produced a downloadable document containing them. Within days of Jones publishing a blog entry about warchalking, articles appeared in dozens of publications and stories appeared on several major television news programs around the world.

The word is formed by analogy to wardriving, the practice of driving around an area in a car to detect open Wi-Fi nodes. That term in turn is based on wardialing, the practice of dialing many phone numbers hoping to find a modem.

Having found a Wi-Fi node, the warchalker draws a special symbol on a nearby object, such as a wall, the pavement, or a lamp post. Those offering Wi-Fi service might also draw such a symbol to advertise the availability of their Wi-Fi location, whether commercial or personal.