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πŸ”— SCOOP: Simple Concurrent Object Oriented Programming

πŸ”— Computing πŸ”— Computer science

SCOOP (Simple Concurrent Object Oriented Programming) is a concurrency model designed for the Eiffel programming language, conceived by Eiffel's creator and designer, Bertrand Meyer.

SCOOP defines a way for an object oriented program to be written without the concept of threads, locks, or other typical multiprogramming methods. This allows the compiler or runtime environment to optimize the amount of concurrency as well as eliminate typical design flaws such as deadlock.

The model was first designed in the early 1990s and published in 1993 in the Communications of the ACM An updated version was described in chapter 30 of the book Object-Oriented Software Construction. A prototype implementation was developed in 1995 by Eiffel Software. An article by Compton and Walker provides an overview of SCOOP and describes another early implementation. Nienaltowski, Arslan and Meyer have published a description of the model as of 2003. Work on SCOOP proceeded at the Chair of Software Engineering at ETH Zurich. SCOOP became available as a standard part of EiffelStudio early in 2011.

πŸ”— Martello Tower

πŸ”— Military history πŸ”— Military history/Military science, technology, and theory πŸ”— Architecture πŸ”— England πŸ”— Military history/Fortifications πŸ”— Military history/Napoleonic era πŸ”— Ireland πŸ”— Kent πŸ”— Military history/European military history πŸ”— Military history/British military history πŸ”— Irish Maritime

Martello towers, sometimes known simply as Martellos, are small defensive forts that were built across the British Empire during the 19th century, from the time of the French Revolutionary Wars onwards. Most were coastal forts.

They stand up to 40 feet (12Β m) high (with two floors) and typically had a garrison of one officer and 15–25 men. Their round structure and thick walls of solid masonry made them resistant to cannon fire, while their height made them an ideal platform for a single heavy artillery piece, mounted on the flat roof and able to traverse, and hence fire, over a complete 360Β° circle. A few towers had moats or other batteries and works attached for extra defence.

The Martello towers were used during the first half of the 19th century, but became obsolete with the introduction of powerful rifled artillery. Many have survived to the present day, often preserved as historic monuments.

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πŸ”— List of video games considered the best

πŸ”— Video games πŸ”— Lists

This is a list of video games that multiple video game journalists and critics have considered to be among the best of all time. The games listed here are included on at least six separate "best/greatest of all time" lists from different publications, as chosen by their editorial staffs.

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πŸ”— Asus Eee PC

πŸ”— Computing πŸ”— Linux

The ASUS Eee PC is a netbook computer line from Asus, and a part of the ASUS Eee product family. At the time of its introduction in late 2007, it was noted for its combination of a lightweight, Linux-based operating system, solid-state drive (SSD), and relatively low cost. Newer models added the options of Microsoft Windows operating system and rotating media hard disk drives (HDD), and initially retailed for up to 500 euros.

The first Eee PC was a milestone in the personal computer business, launching the netbook category of small, low-cost laptops in the West (in Japan, subnotebooks had long been a staple in computing). According to Asus, the name Eee derives from "the three Es", an abbreviation of its advertising slogan for the device: "Easy to learn, Easy to work, Easy to play".

In January 2013, ASUS officially ended production of their Eee PC series, citing declining sales due to consumers favoring tablets and Ultrabooks over netbooks. However, they subsequently restarted the line with the release of the EeeBook series in 2015.

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πŸ”— Gilbert U-238 Atomic Energy Laboratory

πŸ”— Education πŸ”— Toys

The Gilbert U-238 Atomic Energy Lab is a toy lab set that was produced by Alfred Carlton Gilbert, who was an American athlete, magician, toy-maker, business man, and inventor of the well-known Erector Set. The Atomic Energy Lab was released by the A. C. Gilbert Company in 1950. The kit's intention was to allow children to create and watch nuclear and chemical reactions using radioactive material.

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πŸ”— Mumps (Programming Language)

πŸ”— Computing πŸ”— Computing/Software πŸ”— Computing/Early computers πŸ”— Project-independent assessment

MUMPS ("Massachusetts General Hospital Utility Multi-Programming System"), or M, is an imperative, high-level programming language with an integrated transaction processing key–value database. It was originally developed at Massachusetts General Hospital for managing patient medical records and hospital laboratory information systems.

MUMPS technology has since expanded as the predominant database for health information systems and electronic health records in the United States. MUMPS-based information systems, such as Epic Systems', provide health information services for over 78% of patients across the U.S.

A unique feature of the MUMPS technology is its integrated database language, allowing direct, high-speed read-write access to permanent disk storage.

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πŸ”— Barbados 4–2 Grenada

πŸ”— Caribbean πŸ”— Football πŸ”— Caribbean/Barbados πŸ”— Grenada

On January 27, 1994, the national football teams of Barbados and Grenada played against each other as part of the qualification round for the 1994 Caribbean Cup. Barbados won 4-2 in extra time. In the last minutes of regular time, both teams attempted to score own goals. The result has been described as "one of the strangest matches ever".

In the 1994 Caribbean Cup, the tournament organisers implemented a variant of the golden goal rule: the first goal scored in extra-time not only won the match, but was also worth two goals. Barbados needed to win the match by a margin of at least two goals to qualify for the final tournament over Grenada. Barbados led the game 2-0 until Grenada scored at the 83rd minute, bringing the score to 2-1. Barbados then deliberately scored an own goal, tying the game at 2-2, to force extra-time so that they could take advantage of the golden goal rule to achieve their needed two-goal margin. This resulted in an unusual situation: for the last three minutes of the match, Grenada tried to score in both goals. Either outcome (3–2 on points, or 2–3 via goal difference) would have advanced them to the finals, while Barbados had to defend both goals. Ultimately, Barbados was able to prevent Grenada from scoring, forcing extra-time. Barbados then scored the golden goal to win the match.

The outcome of the match was criticised by Grenadian coach James Clarkson, who felt that his team had been unfairly prevented from advancing to the finals. However, given the fact that the unusual tournament rules had not been broken, FIFA cleared Barbados of any wrongdoing.

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πŸ”— Bicameral Mentality

πŸ”— Philosophy πŸ”— Skepticism πŸ”— Psychology πŸ”— Philosophy/Contemporary philosophy πŸ”— Philosophy/Philosophy of mind πŸ”— Alternative Views πŸ”— Neuroscience

Bicameral mentality is a hypothesis introduced by Julian Jaynes who argued human ancestors as late as the ancient Greeks did not consider emotions and desires as stemming from their own minds but as the consequences of actions of gods external to themselves. The theory posits that the human mind once operated in a state in which cognitive functions were divided between one part of the brain which appears to be "speaking", and a second part which listens and obeysβ€”a bicameral mind, and that the breakdown of this division gave rise to consciousness in humans. The term was coined by Jaynes who presented the idea in his 1976 book The Origin of Consciousness in the Breakdown of the Bicameral Mind, wherein he made the case that a bicameral mentality was the normal and ubiquitous state of the human mind as recently as 3,000 years ago, near the end of the Mediterranean bronze age.

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πŸ”— Ryan Model 147

πŸ”— Aviation πŸ”— Military history πŸ”— Military history/Military aviation πŸ”— Military history/North American military history πŸ”— Military history/United States military history πŸ”— Military history/Military science, technology, and theory πŸ”— Aviation/aircraft πŸ”— Military history/Cold War

The Ryan Model 147 Lightning Bug is a jet-powered drone, or unmanned aerial vehicle, produced and developed by Ryan Aeronautical from the earlier Ryan Firebee target drone series.

Beginning in 1962, the Model 147 was introduced as a reconnaissance RPV (Remotely Piloted Vehicle, nomenclature of that era) for a United States Air Force project named Fire Fly. Over the next decade β€” assisted with secret funding from the recently formed National Reconnaissance Office along with support of the Strategic Air Command and Ryan Aeronautical's own resources β€” the basic Model 147 design would be developed into a diverse series of variants configured for a wide array of mission-specific roles, with multiple new systems, sensors and payloads used, modified and improved upon during the operational deployment of these drones in Southeast Asia. Missions performed by the Model 147 series RPVs included high- and low-altitude photographic and electronic aerial reconnaissance, surveillance, decoy, electronic warfare, signals intelligence, and psychological warfare.

The Ryan drones were designed without landing gear for simplicity and to save weight. Like its Firebee predecessor, the Model 147 could either be air-launched from a larger carrier aircraft or launched from the ground using a solid rocket booster; at completion of its mission the drone deployed its own recovery parachute which could be snatched in mid-air by a recovery helicopter (in a combat environment it was naturally not desired to recover the drone on, from or near enemy territory and ground or water impact could also cause damage to or loss of the drone or its payload).

At the end of the Vietnam War in 1975 the U.S. military's available funding and need for combat drones severely declined, even as Teledyne Ryan introduced further advanced developments of the Model 147 series such as the BGM-34 strike and defense suppression RPVs. Costs of maintaining the Lightning Bugs at full readiness could no longer be justified. Only by the 1990s did substantial interest, organization and funding again emerge from the U.S. Air Force and intelligence agencies to develop, acquire and widely deploy combat UAVs.

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πŸ”— Quasicrystals

πŸ”— Physics πŸ”— Chemistry πŸ”— Geology πŸ”— Rocks and minerals

A quasiperiodic crystal, or quasicrystal, is a structure that is ordered but not periodic. A quasicrystalline pattern can continuously fill all available space, but it lacks translational symmetry. While crystals, according to the classical crystallographic restriction theorem, can possess only two-, three-, four-, and six-fold rotational symmetries, the Bragg diffraction pattern of quasicrystals shows sharp peaks with other symmetry ordersβ€”for instance, five-fold.

Aperiodic tilings were discovered by mathematicians in the early 1960s, and, some twenty years later, they were found to apply to the study of natural quasicrystals. The discovery of these aperiodic forms in nature has produced a paradigm shift in the fields of crystallography. Quasicrystals had been investigated and observed earlier, but, until the 1980s, they were disregarded in favor of the prevailing views about the atomic structure of matter. In 2009, after a dedicated search, a mineralogical finding, icosahedrite, offered evidence for the existence of natural quasicrystals.

Roughly, an ordering is non-periodic if it lacks translational symmetry, which means that a shifted copy will never match exactly with its original. The more precise mathematical definition is that there is never translational symmetry in more than n – 1 linearly independent directions, where n is the dimension of the space filled, e.g., the three-dimensional tiling displayed in a quasicrystal may have translational symmetry in two directions. Symmetrical diffraction patterns result from the existence of an indefinitely large number of elements with a regular spacing, a property loosely described as long-range order. Experimentally, the aperiodicity is revealed in the unusual symmetry of the diffraction pattern, that is, symmetry of orders other than two, three, four, or six. In 1982 materials scientist Dan Shechtman observed that certain aluminium-manganese alloys produced the unusual diffractograms which today are seen as revelatory of quasicrystal structures. Due to fear of the scientific community's reaction, it took him two years to publish the results for which he was awarded the Nobel Prize in Chemistry in 2011. On 25 October 2018, Luca Bindi and Paul Steinhardt were awarded the Aspen Institute 2018 Prize for collaboration and scientific research between Italy and the United States.

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