Random Articles (Page 4)
Have a deep view into what people are curious about.
π Nika Riots (532 C.E.)
The Nika riots (Greek: Ξ£ΟΞ¬ΟΞΉΟ ΟΞΏαΏ¦ ΞΞ―ΞΊΞ±, romanized:Β StΓ‘sis toΓ» NΓka), Nika revolt or Nika sedition took place against Byzantine emperor Justinian I in Constantinople over the course of a week in 532 C.E. They are often regarded as the most violent riots in the city's history, with nearly half of Constantinople being burned or destroyed and tens of thousands of people killed.
Discussed on
- "Nika Riots (532 C.E.)" | 2023-12-22 | 11 Upvotes 2 Comments
π Electro Gyrocator
The Electro Gyro-Cator was claimed to be the world's first automated commercially available automotive navigation system. It was co-developed by Honda, Alpine, and Stanley Electric Co..
Unlike most navigation systems of today, it did not use GPS Satellites to maintain its position and discern movement of the vehicle. Rather, it was an Inertial navigation system, because it contained a helium gas gyroscope that could detect both rotation and movement. A special servo gear was also attached to the transmission housing to feed information to the Gyro-Cator to help maintain position, map speed and distance traveled.
Transparent maps were placed inside the unit and it would scroll them past a 6 inch monochrome CRT illuminated screen as the car traveled along. The monitor would indicate by a series of circles (or cross hairs) on the screen to show the vehicle's current location or display lines for path of travel. A marking pen was also included to help make personal indicators on the map if needed. Adjustments could be made to change the display scale, position, rotation, brightness, and contrast. In its only year of production in 1981, it was announced as an option on that year's Honda Accord and Honda Vigor, but at Β₯300,000 ($2,746 USD), it was almost a quarter of the value of the car. It is not clear how many units were actually sold to customers as a "dealer option". A patent for gyroscope design was introduced to the US in design patent D274332.
Documented weight for the unit was roughly 20Β lb (9Β kg). A display unit, with a cutaway of the Gyroscope, is currently shown at the Honda Collection Hall at Twin Ring Motegi, Japan.
Discussed on
- "Electro Gyrocator" | 2023-01-28 | 101 Upvotes 57 Comments
π Giffard Dirigible
The Giffard dirigible or Giffard airship was an airship built in France in 1852 by Henri Giffard, the first powered and steerable (French: dirigeable β "directable") airship to fly. The craft featured an elongated hydrogen-filled envelope that tapered to a point at each end. From this was suspended a long beam with a triangular, sail-like rudder at its aft end, and beneath the beam a platform for the pilot and steam engine. Due to the highly flammable nature of the lift gas, special precautions were taken to minimise the potential for the envelope to be ignited by the engine beneath it. The engine's exhaust was diverted downwards to a long pipe projecting below the platform, and the area surrounding the boiler's stoke hole was surrounded by wire gauze. On 24 September 1852, Giffard flew the airship from the hippodrome at Place de l'Etoile to Γlancourt, covering the 27Β km (17Β mi) in around 3 hours, demonstrating maneuvering along the way. The engine, however, was not sufficiently powerful to allow Giffard to fly against the wind to make a return journey.
π Kettle Logic
Kettle logic (la logique du chaudron in the original French) is a rhetorical device wherein one uses multiple arguments to defend a point, but the arguments are inconsistent with each other.
Jacques Derrida uses this expression in reference to the humorous "kettle-story", that Sigmund Freud relates in The Interpretation of Dreams (1900) and Jokes and Their Relation to the Unconscious (1905).
Discussed on
- "Kettle Logic" | 2022-03-10 | 139 Upvotes 80 Comments
π Thomas Harriot
Thomas Harriot (Oxford, c. 1560 β London, 2 July 1621), also spelled Harriott, Hariot or Heriot, was an English astronomer, mathematician, ethnographer and translator who made advances within the scientific field. Thomas Harriot was recognized for his contributions in astronomy, mathematics, and navigational techniques. Harriot worked closely with John White to create advanced maps for navigation. While Harriot worked extensively on numerous papers on the subjects of astronomy, mathematics, and navigation the amount of work that was actually published was sparse. So sparse that the only publication that has been produced by Harriot was The Briefe and True Report of the New Found Land of Virginia. The premise of the book includes descriptions of English settlements and financial issues in Virginia at the time. He is sometimes credited with the introduction of the potato to the British Isles. Harriot was the first person to make a drawing of the Moon through a telescope, on 26 July 1609, over four months before Galileo Galilei.
After graduating from St Mary Hall, Oxford, Harriot travelled to the Americas, accompanying the 1585 expedition to Roanoke island funded by Sir Walter Raleigh and led by Sir Ralph Lane. Harriot was a vital member of the venture, having learned and translating the Carolina Algonquian language from two Native Americans: Wanchese and Manteo. On his return to England, he worked for the 9th Earl of Northumberland. At the Earl's house, he became a prolific mathematician and astronomer to whom the theory of refraction is attributed.
Discussed on
- "Thomas Harriot" | 2014-05-25 | 12 Upvotes 2 Comments
π Toyota Century
The Toyota Century (Japanese: γγ¨γΏγ»γ»γ³γγ₯γͺγΌ, Hepburn: Toyota SenchurΔ«) is a limousine produced mainly for the Japanese market, serving as Toyota's flagship car within Japan; globally the unrelated Lexus LS series is Toyota's flagship luxury model. Production of the Century began in 1967, and the model received only minor changes until redesigns in 1997 and 2018.
The Century derived its name from the 100th birthday of Sakichi Toyoda (born 14 February 1867), the founder of Toyota Industries. It is often used by the Imperial House of Japan, the Prime Minister of Japan, senior Japanese government leaders, and high-level executive businessmen. The Century is comparable in purpose to the Austin Princess/Daimler DS420, Cadillac Series 70, Mercedes-Benz 600 series, Chinese Red Flag, Rolls-Royce, and Russian ZIS/ZIL limousines.
The first-generation Century was available with only a V8 engine (the third post-war Japanese-built sedan so-equipped) at its introduction in 1967 until a full platform redesign in 1997. The second generation was only installed with a Toyota-designed and -built V12, an engine bespoke to the Century, until 2018, when the power-train reverted to a V8 with the addition of Toyota's hybrid technology.
While the Century is a premium, full-size luxury sedan, it is not available at Japanese Lexus dealerships; it can only be purchased at specifically identified Toyota Store locations. The gold phoenix logo used throughout is called the HΕ'Ε (ι³³ε°) or FushichΕ (δΈζ»ι³₯) from Sinospheric mythology, representing the Imperial House of Japan, and the image can be found throughout Asia, such as the Kinkaku-ji in Kyoto.
The exterior styling of the Century has, with some modifications, remained unchanged since its introduction, primarily due to its perception as denoting conservative success. Its appearance is iconic in Asian countries and is usually painted black. The closest Japanese competitor was the Nissan President, with a similar status reputation although, during the 1960s and '70s, the high market positioning was also shared with the Mitsubishi Debonair. In the 1970s, two other Japanese competitors introduced large sedans β the Isuzu Statesman de Ville and the Mazda Roadpacer (both derived from General Motors-Australia products) β which were short-lived.
Discussed on
- "Toyota Century" | 2022-09-12 | 12 Upvotes 2 Comments
π Oberon Operating System
The Oberon System is a modular, single-user, single-process, multitasking operating system written in the programming language of the same name. It was originally developed in the late 1980s at ETH ZΓΌrich. The Oberon System has an unconventional visual text user interface instead of a conventional CLI or GUI. This "TUI" was very innovative in its time and influenced the design of the Acme text editor for the Plan 9 from Bell Labs operating system.
The latest version of the Oberon System, Project Oberon 2013, is still maintained by Niklaus Wirth and a number of collaborators but older ETH versions of the Oberon Systems have been orphaned. The Oberon System also evolved into the multi-process, SMP-capable Bluebottle operating system, with a zooming user interface.
Discussed on
- "Oberon Operating System" | 2019-10-28 | 196 Upvotes 93 Comments
- "Oberon System, an OS Written in Oberon" | 2015-12-25 | 104 Upvotes 40 Comments
π Simulations and games in economics education
A simulation game is "a game that contains a mixture of skill, chance, and strategy to simulate an aspect of reality, such as a stock exchange". Similarly, Finnish author Virpi RuohomΓ€ki states that "a simulation game combines the features of a game (competition, cooperation, rules, participants, roles) with those of a simulation (incorporation of critical features of reality). A game is a simulation game if its rules refer to an empirical model of reality". A properly built simulation game used to teach or learn economics would closely follow the assumptions and rules of the theoretical models within this discipline.
Discussed on
- "Simulations and games in economics education" | 2023-03-18 | 79 Upvotes 25 Comments
π Zero Knowledge Proofs
In cryptography, a zero-knowledge proof or zero-knowledge protocol is a method by which one party (the prover) can prove to another party (the verifier) that they know a value x, without conveying any information apart from the fact that they know the value x. The essence of zero-knowledge proofs is that it is trivial to prove that one possesses knowledge of certain information by simply revealing it; the challenge is to prove such possession without revealing the information itself or any additional information.
If proving a statement requires that the prover possesses some secret information, then the verifier will not be able to prove the statement to anyone else without possessing the secret information. The statement being proved must include the assertion that the prover has such knowledge, but not the knowledge itself. Otherwise, the statement would not be proved in zero-knowledge because it provides the verifier with additional information about the statement by the end of the protocol. A zero-knowledge proof of knowledge is a special case when the statement consists only of the fact that the prover possesses the secret information.
Interactive zero-knowledge proofs require interaction between the individual (or computer system) proving their knowledge and the individual validating the proof.
A protocol implementing zero-knowledge proofs of knowledge must necessarily require interactive input from the verifier. This interactive input is usually in the form of one or more challenges such that the responses from the prover will convince the verifier if and only if the statement is true, i.e., if the prover does possess the claimed knowledge. If this were not the case, the verifier could record the execution of the protocol and replay it to convince someone else that they possess the secret information. The new party's acceptance is either justified since the replayer does possess the information (which implies that the protocol leaked information, and thus, is not proved in zero-knowledge), or the acceptance is spurious, i.e., was accepted from someone who does not actually possess the information.
Some forms of non-interactive zero-knowledge proofs exist, but the validity of the proof relies on computational assumptions (typically the assumptions of an ideal cryptographic hash function).
Discussed on
- "Zero Knowledge Proofs" | 2013-04-14 | 60 Upvotes 19 Comments
π Granular convection
Granular convection, or granular segregation, is a phenomenon where granular material subjected to shaking or vibration will exhibit circulation patterns similar to types of fluid convection. It is sometimes described as the Brazil nut effect when the largest particles end up on the surface of a granular material containing a mixture of variously sized objects; this derives from the example of a typical container of mixed nuts, where the largest will be Brazil nuts. The phenomenon is also known as the muesli effect since it is seen in packets of breakfast cereal containing particles of different sizes but similar density, such as muesli mix.
Under experimental conditions, granular convection of variously sized particles has been observed forming convection cells similar to fluid motion. The convection of granular flows is becoming a well-understood phenomenon.
Discussed on
- "Granular convection" | 2019-12-10 | 46 Upvotes 22 Comments